--- /dev/null
+Introduction
+=============
+
+UBIFS file-system stands for UBI File System. UBI stands for "Unsorted
+Block Images". UBIFS is a flash file system, which means it is designed
+to work with flash devices. It is important to understand, that UBIFS
+is completely different to any traditional file-system in Linux, like
+Ext2, XFS, JFS, etc. UBIFS represents a separate class of file-systems
+which work with MTD devices, not block devices. The other Linux
+file-system of this class is JFFS2.
+
+To make it more clear, here is a small comparison of MTD devices and
+block devices.
+
+1 MTD devices represent flash devices and they consist of eraseblocks of
+ rather large size, typically about 128KiB. Block devices consist of
+ small blocks, typically 512 bytes.
+2 MTD devices support 3 main operations - read from some offset within an
+ eraseblock, write to some offset within an eraseblock, and erase a whole
+ eraseblock. Block devices support 2 main operations - read a whole
+ block and write a whole block.
+3 The whole eraseblock has to be erased before it becomes possible to
+ re-write its contents. Blocks may be just re-written.
+4 Eraseblocks become worn out after some number of erase cycles -
+ typically 100K-1G for SLC NAND and NOR flashes, and 1K-10K for MLC
+ NAND flashes. Blocks do not have the wear-out property.
+5 Eraseblocks may become bad (only on NAND flashes) and software should
+ deal with this. Blocks on hard drives typically do not become bad,
+ because hardware has mechanisms to substitute bad blocks, at least in
+ modern LBA disks.
+
+It should be quite obvious why UBIFS is very different to traditional
+file-systems.
+
+UBIFS works on top of UBI. UBI is a separate software layer which may be
+found in drivers/mtd/ubi. UBI is basically a volume management and
+wear-leveling layer. It provides so called UBI volumes which is a higher
+level abstraction than a MTD device. The programming model of UBI devices
+is very similar to MTD devices - they still consist of large eraseblocks,
+they have read/write/erase operations, but UBI devices are devoid of
+limitations like wear and bad blocks (items 4 and 5 in the above list).
+
+In a sense, UBIFS is a next generation of JFFS2 file-system, but it is
+very different and incompatible to JFFS2. The following are the main
+differences.
+
+* JFFS2 works on top of MTD devices, UBIFS depends on UBI and works on
+ top of UBI volumes.
+* JFFS2 does not have on-media index and has to build it while mounting,
+ which requires full media scan. UBIFS maintains the FS indexing
+ information on the flash media and does not require full media scan,
+ so it mounts many times faster than JFFS2.
+* JFFS2 is a write-through file-system, while UBIFS supports write-back,
+ which makes UBIFS much faster on writes.
+
+Similarly to JFFS2, UBIFS supports on-the-flight compression which makes
+it possible to fit quite a lot of data to the flash.
+
+Similarly to JFFS2, UBIFS is tolerant of unclean reboots and power-cuts.
+It does not need stuff like ckfs.ext2. UBIFS automatically replays its
+journal and recovers from crashes, ensuring that the on-flash data
+structures are consistent.
+
+UBIFS scales logarithmically (most of the data structures it uses are
+trees), so the mount time and memory consumption do not linearly depend
+on the flash size, like in case of JFFS2. This is because UBIFS
+maintains the FS index on the flash media. However, UBIFS depends on
+UBI, which scales linearly. So overall UBI/UBIFS stack scales linearly.
+Nevertheless, UBI/UBIFS scales considerably better than JFFS2.
+
+The authors of UBIFS believe, that it is possible to develop UBI2 which
+would scale logarithmically as well. UBI2 would support the same API as UBI,
+but it would be binary incompatible to UBI. So UBIFS would not need to be
+changed to use UBI2
+
+
+Mount options
+=============
+
+(*) == default.
+
+norm_unmount (*) commit on unmount; the journal is committed
+ when the file-system is unmounted so that the
+ next mount does not have to replay the journal
+ and it becomes very fast;
+fast_unmount do not commit on unmount; this option makes
+ unmount faster, but the next mount slower
+ because of the need to replay the journal.
+
+
+Quick usage instructions
+========================
+
+The UBI volume to mount is specified using "ubiX_Y" or "ubiX:NAME" syntax,
+where "X" is UBI device number, "Y" is UBI volume number, and "NAME" is
+UBI volume name.
+
+Mount volume 0 on UBI device 0 to /mnt/ubifs:
+$ mount -t ubifs ubi0_0 /mnt/ubifs
+
+Mount "rootfs" volume of UBI device 0 to /mnt/ubifs ("rootfs" is volume
+name):
+$ mount -t ubifs ubi0:rootfs /mnt/ubifs
+
+The following is an example of the kernel boot arguments to attach mtd0
+to UBI and mount volume "rootfs":
+ubi.mtd=0 root=ubi0:rootfs rootfstype=ubifs
+
+
+Module Parameters for Debugging
+===============================
+
+When UBIFS has been compiled with debugging enabled, there are 3 module
+parameters that are available to control aspects of testing and debugging.
+The parameters are unsigned integers where each bit controls an option.
+The parameters are:
+
+debug_msgs Selects which debug messages to display, as follows:
+
+ Message Type Flag value
+
+ General messages 1
+ Journal messages 2
+ Mount messages 4
+ Commit messages 8
+ LEB search messages 16
+ Budgeting messages 32
+ Garbage collection messages 64
+ Tree Node Cache (TNC) messages 128
+ LEB properties (lprops) messages 256
+ Input/output messages 512
+ Log messages 1024
+ Scan messages 2048
+ Recovery messages 4096
+
+debug_chks Selects extra checks that UBIFS can do while running:
+
+ Check Flag value
+
+ General checks 1
+ Check Tree Node Cache (TNC) 2
+ Check indexing tree size 4
+ Check orphan area 8
+ Check old indexing tree 16
+ Check LEB properties (lprops) 32
+ Check leaf nodes and inodes 64
+
+debug_tsts Selects a mode of testing, as follows:
+
+ Test mode Flag value
+
+ Force in-the-gaps method 2
+ Failure mode for recovery testing 4
+
+For example, set debug_msgs to 5 to display General messages and Mount
+messages.
+
+
+References
+==========
+
+UBIFS documentation and FAQ/HOWTO at the MTD web site:
+http://www.linux-mtd.infradead.org/doc/ubifs.html
+http://www.linux-mtd.infradead.org/faq/ubifs.html
W: http://www.linux-mtd.infradead.org/doc/jffs2.html
S: Maintained
+UBI FILE SYSTEM (UBIFS)
+P: Artem Bityutskiy
+M: dedekind@infradead.org
+P: Adrian Hunter
+M: ext-adrian.hunter@nokia.com
+L: linux-mtd@lists.infradead.org
+T: git git://git.infradead.org/~dedekind/ubifs-2.6.git
+W: http://www.linux-mtd.infradead.org/doc/ubifs.html
+S: Maintained
+
JFS FILESYSTEM
P: Dave Kleikamp
M: shaggy@austin.ibm.com
endchoice
+# UBIFS File system configuration
+source "fs/ubifs/Kconfig"
+
config CRAMFS
tristate "Compressed ROM file system support (cramfs)"
depends on BLOCK
obj-$(CONFIG_UFS_FS) += ufs/
obj-$(CONFIG_EFS_FS) += efs/
obj-$(CONFIG_JFFS2_FS) += jffs2/
+obj-$(CONFIG_UBIFS_FS) += ubifs/
obj-$(CONFIG_AFFS_FS) += affs/
obj-$(CONFIG_ROMFS_FS) += romfs/
obj-$(CONFIG_QNX4FS_FS) += qnx4/
* WB_SYNC_HOLD is a hack for sys_sync(): reattach the inode to sb->s_dirty so
* that it can be located for waiting on in __writeback_single_inode().
*
- * Called under inode_lock.
- *
* If `bdi' is non-zero then we're being asked to writeback a specific queue.
* This function assumes that the blockdev superblock's inodes are backed by
* a variety of queues, so all inodes are searched. For other superblocks,
* on the writer throttling path, and we get decent balancing between many
* throttled threads: we don't want them all piling up on inode_sync_wait.
*/
-static void
-sync_sb_inodes(struct super_block *sb, struct writeback_control *wbc)
+void generic_sync_sb_inodes(struct super_block *sb,
+ struct writeback_control *wbc)
{
const unsigned long start = jiffies; /* livelock avoidance */
+ spin_lock(&inode_lock);
if (!wbc->for_kupdate || list_empty(&sb->s_io))
queue_io(sb, wbc->older_than_this);
if (!list_empty(&sb->s_more_io))
wbc->more_io = 1;
}
+ spin_unlock(&inode_lock);
return; /* Leave any unwritten inodes on s_io */
}
+EXPORT_SYMBOL_GPL(generic_sync_sb_inodes);
+
+static void sync_sb_inodes(struct super_block *sb,
+ struct writeback_control *wbc)
+{
+ generic_sync_sb_inodes(sb, wbc);
+}
/*
* Start writeback of dirty pagecache data against all unlocked inodes.
* be unmounted by the time it is released.
*/
if (down_read_trylock(&sb->s_umount)) {
- if (sb->s_root) {
- spin_lock(&inode_lock);
+ if (sb->s_root)
sync_sb_inodes(sb, wbc);
- spin_unlock(&inode_lock);
- }
up_read(&sb->s_umount);
}
spin_lock(&sb_lock);
(inodes_stat.nr_inodes - inodes_stat.nr_unused) +
nr_dirty + nr_unstable;
wbc.nr_to_write += wbc.nr_to_write / 2; /* Bit more for luck */
- spin_lock(&inode_lock);
sync_sb_inodes(sb, &wbc);
- spin_unlock(&inode_lock);
}
/*
--- /dev/null
+config UBIFS_FS
+ tristate "UBIFS file system support"
+ select CRC16
+ select CRC32
+ select CRYPTO if UBIFS_FS_ADVANCED_COMPR
+ select CRYPTO if UBIFS_FS_LZO
+ select CRYPTO if UBIFS_FS_ZLIB
+ select CRYPTO_LZO if UBIFS_FS_LZO
+ select CRYPTO_DEFLATE if UBIFS_FS_ZLIB
+ depends on MTD_UBI
+ help
+ UBIFS is a file system for flash devices which works on top of UBI.
+
+config UBIFS_FS_XATTR
+ bool "Extended attributes support"
+ depends on UBIFS_FS
+ help
+ This option enables support of extended attributes.
+
+config UBIFS_FS_ADVANCED_COMPR
+ bool "Advanced compression options"
+ depends on UBIFS_FS
+ help
+ This option allows to explicitly choose which compressions, if any,
+ are enabled in UBIFS. Removing compressors means inbility to read
+ existing file systems.
+
+ If unsure, say 'N'.
+
+config UBIFS_FS_LZO
+ bool "LZO compression support" if UBIFS_FS_ADVANCED_COMPR
+ depends on UBIFS_FS
+ default y
+ help
+ LZO compressor is generally faster then zlib but compresses worse.
+ Say 'Y' if unsure.
+
+config UBIFS_FS_ZLIB
+ bool "ZLIB compression support" if UBIFS_FS_ADVANCED_COMPR
+ depends on UBIFS_FS
+ default y
+ help
+ Zlib copresses better then LZO but it is slower. Say 'Y' if unsure.
+
+# Debugging-related stuff
+config UBIFS_FS_DEBUG
+ bool "Enable debugging"
+ depends on UBIFS_FS
+ select DEBUG_FS
+ select KALLSYMS_ALL
+ help
+ This option enables UBIFS debugging.
+
+config UBIFS_FS_DEBUG_MSG_LVL
+ int "Default message level (0 = no extra messages, 3 = lots)"
+ depends on UBIFS_FS_DEBUG
+ default "0"
+ help
+ This controls the amount of debugging messages produced by UBIFS.
+ If reporting bugs, please try to have available a full dump of the
+ messages at level 1 while the misbehaviour was occurring. Level 2
+ may become necessary if level 1 messages were not enough to find the
+ bug. Generally Level 3 should be avoided.
+
+config UBIFS_FS_DEBUG_CHKS
+ bool "Enable extra checks"
+ depends on UBIFS_FS_DEBUG
+ help
+ If extra checks are enabled UBIFS will check the consistency of its
+ internal data structures during operation. However, UBIFS performance
+ is dramatically slower when this option is selected especially if the
+ file system is large.
--- /dev/null
+obj-$(CONFIG_UBIFS_FS) += ubifs.o
+
+ubifs-y += shrinker.o journal.o file.o dir.o super.o sb.o io.o
+ubifs-y += tnc.o master.o scan.o replay.o log.o commit.o gc.o orphan.o
+ubifs-y += budget.o find.o tnc_commit.o compress.o lpt.o lprops.o
+ubifs-y += recovery.o ioctl.o lpt_commit.o tnc_misc.o
+
+ubifs-$(CONFIG_UBIFS_FS_DEBUG) += debug.o
+ubifs-$(CONFIG_UBIFS_FS_XATTR) += xattr.o
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ * Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file implements the budgeting sub-system which is responsible for UBIFS
+ * space management.
+ *
+ * Factors such as compression, wasted space at the ends of LEBs, space in other
+ * journal heads, the effect of updates on the index, and so on, make it
+ * impossible to accurately predict the amount of space needed. Consequently
+ * approximations are used.
+ */
+
+#include "ubifs.h"
+#include <linux/writeback.h>
+#include <asm/div64.h>
+
+/*
+ * When pessimistic budget calculations say that there is no enough space,
+ * UBIFS starts writing back dirty inodes and pages, doing garbage collection,
+ * or committing. The below constants define maximum number of times UBIFS
+ * repeats the operations.
+ */
+#define MAX_SHRINK_RETRIES 8
+#define MAX_GC_RETRIES 4
+#define MAX_CMT_RETRIES 2
+#define MAX_NOSPC_RETRIES 1
+
+/*
+ * The below constant defines amount of dirty pages which should be written
+ * back at when trying to shrink the liability.
+ */
+#define NR_TO_WRITE 16
+
+/**
+ * struct retries_info - information about re-tries while making free space.
+ * @prev_liability: previous liability
+ * @shrink_cnt: how many times the liability was shrinked
+ * @shrink_retries: count of liability shrink re-tries (increased when
+ * liability does not shrink)
+ * @try_gc: GC should be tried first
+ * @gc_retries: how many times GC was run
+ * @cmt_retries: how many times commit has been done
+ * @nospc_retries: how many times GC returned %-ENOSPC
+ *
+ * Since we consider budgeting to be the fast-path, and this structure has to
+ * be allocated on stack and zeroed out, we make it smaller using bit-fields.
+ */
+struct retries_info {
+ long long prev_liability;
+ unsigned int shrink_cnt;
+ unsigned int shrink_retries:5;
+ unsigned int try_gc:1;
+ unsigned int gc_retries:4;
+ unsigned int cmt_retries:3;
+ unsigned int nospc_retries:1;
+};
+
+/**
+ * shrink_liability - write-back some dirty pages/inodes.
+ * @c: UBIFS file-system description object
+ * @nr_to_write: how many dirty pages to write-back
+ *
+ * This function shrinks UBIFS liability by means of writing back some amount
+ * of dirty inodes and their pages. Returns the amount of pages which were
+ * written back. The returned value does not include dirty inodes which were
+ * synchronized.
+ *
+ * Note, this function synchronizes even VFS inodes which are locked
+ * (@i_mutex) by the caller of the budgeting function, because write-back does
+ * not touch @i_mutex.
+ */
+static int shrink_liability(struct ubifs_info *c, int nr_to_write)
+{
+ int nr_written;
+ struct writeback_control wbc = {
+ .sync_mode = WB_SYNC_NONE,
+ .range_end = LLONG_MAX,
+ .nr_to_write = nr_to_write,
+ };
+
+ generic_sync_sb_inodes(c->vfs_sb, &wbc);
+ nr_written = nr_to_write - wbc.nr_to_write;
+
+ if (!nr_written) {
+ /*
+ * Re-try again but wait on pages/inodes which are being
+ * written-back concurrently (e.g., by pdflush).
+ */
+ memset(&wbc, 0, sizeof(struct writeback_control));
+ wbc.sync_mode = WB_SYNC_ALL;
+ wbc.range_end = LLONG_MAX;
+ wbc.nr_to_write = nr_to_write;
+ generic_sync_sb_inodes(c->vfs_sb, &wbc);
+ nr_written = nr_to_write - wbc.nr_to_write;
+ }
+
+ dbg_budg("%d pages were written back", nr_written);
+ return nr_written;
+}
+
+
+/**
+ * run_gc - run garbage collector.
+ * @c: UBIFS file-system description object
+ *
+ * This function runs garbage collector to make some more free space. Returns
+ * zero if a free LEB has been produced, %-EAGAIN if commit is required, and a
+ * negative error code in case of failure.
+ */
+static int run_gc(struct ubifs_info *c)
+{
+ int err, lnum;
+
+ /* Make some free space by garbage-collecting dirty space */
+ down_read(&c->commit_sem);
+ lnum = ubifs_garbage_collect(c, 1);
+ up_read(&c->commit_sem);
+ if (lnum < 0)
+ return lnum;
+
+ /* GC freed one LEB, return it to lprops */
+ dbg_budg("GC freed LEB %d", lnum);
+ err = ubifs_return_leb(c, lnum);
+ if (err)
+ return err;
+ return 0;
+}
+
+/**
+ * make_free_space - make more free space on the file-system.
+ * @c: UBIFS file-system description object
+ * @ri: information about previous invocations of this function
+ *
+ * This function is called when an operation cannot be budgeted because there
+ * is supposedly no free space. But in most cases there is some free space:
+ * o budgeting is pessimistic, so it always budgets more then it is actually
+ * needed, so shrinking the liability is one way to make free space - the
+ * cached data will take less space then it was budgeted for;
+ * o GC may turn some dark space into free space (budgeting treats dark space
+ * as not available);
+ * o commit may free some LEB, i.e., turn freeable LEBs into free LEBs.
+ *
+ * So this function tries to do the above. Returns %-EAGAIN if some free space
+ * was presumably made and the caller has to re-try budgeting the operation.
+ * Returns %-ENOSPC if it couldn't do more free space, and other negative error
+ * codes on failures.
+ */
+static int make_free_space(struct ubifs_info *c, struct retries_info *ri)
+{
+ int err;
+
+ /*
+ * If we have some dirty pages and inodes (liability), try to write
+ * them back unless this was tried too many times without effect
+ * already.
+ */
+ if (ri->shrink_retries < MAX_SHRINK_RETRIES && !ri->try_gc) {
+ long long liability;
+
+ spin_lock(&c->space_lock);
+ liability = c->budg_idx_growth + c->budg_data_growth +
+ c->budg_dd_growth;
+ spin_unlock(&c->space_lock);
+
+ if (ri->prev_liability >= liability) {
+ /* Liability does not shrink, next time try GC then */
+ ri->shrink_retries += 1;
+ if (ri->gc_retries < MAX_GC_RETRIES)
+ ri->try_gc = 1;
+ dbg_budg("liability did not shrink: retries %d of %d",
+ ri->shrink_retries, MAX_SHRINK_RETRIES);
+ }
+
+ dbg_budg("force write-back (count %d)", ri->shrink_cnt);
+ shrink_liability(c, NR_TO_WRITE + ri->shrink_cnt);
+
+ ri->prev_liability = liability;
+ ri->shrink_cnt += 1;
+ return -EAGAIN;
+ }
+
+ /*
+ * Try to run garbage collector unless it was already tried too many
+ * times.
+ */
+ if (ri->gc_retries < MAX_GC_RETRIES) {
+ ri->gc_retries += 1;
+ dbg_budg("run GC, retries %d of %d",
+ ri->gc_retries, MAX_GC_RETRIES);
+
+ ri->try_gc = 0;
+ err = run_gc(c);
+ if (!err)
+ return -EAGAIN;
+
+ if (err == -EAGAIN) {
+ dbg_budg("GC asked to commit");
+ err = ubifs_run_commit(c);
+ if (err)
+ return err;
+ return -EAGAIN;
+ }
+
+ if (err != -ENOSPC)
+ return err;
+
+ /*
+ * GC could not make any progress. If this is the first time,
+ * then it makes sense to try to commit, because it might make
+ * some dirty space.
+ */
+ dbg_budg("GC returned -ENOSPC, retries %d",
+ ri->nospc_retries);
+ if (ri->nospc_retries >= MAX_NOSPC_RETRIES)
+ return err;
+ ri->nospc_retries += 1;
+ }
+
+ /* Neither GC nor write-back helped, try to commit */
+ if (ri->cmt_retries < MAX_CMT_RETRIES) {
+ ri->cmt_retries += 1;
+ dbg_budg("run commit, retries %d of %d",
+ ri->cmt_retries, MAX_CMT_RETRIES);
+ err = ubifs_run_commit(c);
+ if (err)
+ return err;
+ return -EAGAIN;
+ }
+ return -ENOSPC;
+}
+
+/**
+ * ubifs_calc_min_idx_lebs - calculate amount of eraseblocks for the index.
+ * @c: UBIFS file-system description object
+ *
+ * This function calculates and returns the number of eraseblocks which should
+ * be kept for index usage.
+ */
+int ubifs_calc_min_idx_lebs(struct ubifs_info *c)
+{
+ int ret;
+ uint64_t idx_size;
+
+ idx_size = c->old_idx_sz + c->budg_idx_growth + c->budg_uncommitted_idx;
+
+ /* And make sure we have twice the index size of space reserved */
+ idx_size <<= 1;
+
+ /*
+ * We do not maintain 'old_idx_size' as 'old_idx_lebs'/'old_idx_bytes'
+ * pair, nor similarly the two variables for the new index size, so we
+ * have to do this costly 64-bit division on fast-path.
+ */
+ if (do_div(idx_size, c->leb_size - c->max_idx_node_sz))
+ ret = idx_size + 1;
+ else
+ ret = idx_size;
+ /*
+ * The index head is not available for the in-the-gaps method, so add an
+ * extra LEB to compensate.
+ */
+ ret += 1;
+ /*
+ * At present the index needs at least 2 LEBs: one for the index head
+ * and one for in-the-gaps method (which currently does not cater for
+ * the index head and so excludes it from consideration).
+ */
+ if (ret < 2)
+ ret = 2;
+ return ret;
+}
+
+/**
+ * ubifs_calc_available - calculate available FS space.
+ * @c: UBIFS file-system description object
+ * @min_idx_lebs: minimum number of LEBs reserved for the index
+ *
+ * This function calculates and returns amount of FS space available for use.
+ */
+long long ubifs_calc_available(const struct ubifs_info *c, int min_idx_lebs)
+{
+ int subtract_lebs;
+ long long available;
+
+ /*
+ * Force the amount available to the total size reported if the used
+ * space is zero.
+ */
+ if (c->lst.total_used <= UBIFS_INO_NODE_SZ &&
+ c->budg_data_growth + c->budg_dd_growth == 0) {
+ /* Do the same calculation as for c->block_cnt */
+ available = c->main_lebs - 2;
+ available *= c->leb_size - c->dark_wm;
+ return available;
+ }
+
+ available = c->main_bytes - c->lst.total_used;
+
+ /*
+ * Now 'available' contains theoretically available flash space
+ * assuming there is no index, so we have to subtract the space which
+ * is reserved for the index.
+ */
+ subtract_lebs = min_idx_lebs;
+
+ /* Take into account that GC reserves one LEB for its own needs */
+ subtract_lebs += 1;
+
+ /*
+ * The GC journal head LEB is not really accessible. And since
+ * different write types go to different heads, we may count only on
+ * one head's space.
+ */
+ subtract_lebs += c->jhead_cnt - 1;
+
+ /* We also reserve one LEB for deletions, which bypass budgeting */
+ subtract_lebs += 1;
+
+ available -= (long long)subtract_lebs * c->leb_size;
+
+ /* Subtract the dead space which is not available for use */
+ available -= c->lst.total_dead;
+
+ /*
+ * Subtract dark space, which might or might not be usable - it depends
+ * on the data which we have on the media and which will be written. If
+ * this is a lot of uncompressed or not-compressible data, the dark
+ * space cannot be used.
+ */
+ available -= c->lst.total_dark;
+
+ /*
+ * However, there is more dark space. The index may be bigger than
+ * @min_idx_lebs. Those extra LEBs are assumed to be available, but
+ * their dark space is not included in total_dark, so it is subtracted
+ * here.
+ */
+ if (c->lst.idx_lebs > min_idx_lebs) {
+ subtract_lebs = c->lst.idx_lebs - min_idx_lebs;
+ available -= subtract_lebs * c->dark_wm;
+ }
+
+ /* The calculations are rough and may end up with a negative number */
+ return available > 0 ? available : 0;
+}
+
+/**
+ * can_use_rp - check whether the user is allowed to use reserved pool.
+ * @c: UBIFS file-system description object
+ *
+ * UBIFS has so-called "reserved pool" which is flash space reserved
+ * for the superuser and for uses whose UID/GID is recorded in UBIFS superblock.
+ * This function checks whether current user is allowed to use reserved pool.
+ * Returns %1 current user is allowed to use reserved pool and %0 otherwise.
+ */
+static int can_use_rp(struct ubifs_info *c)
+{
+ if (current->fsuid == c->rp_uid || capable(CAP_SYS_RESOURCE) ||
+ (c->rp_gid != 0 && in_group_p(c->rp_gid)))
+ return 1;
+ return 0;
+}
+
+/**
+ * do_budget_space - reserve flash space for index and data growth.
+ * @c: UBIFS file-system description object
+ *
+ * This function makes sure UBIFS has enough free eraseblocks for index growth
+ * and data.
+ *
+ * When budgeting index space, UBIFS reserves twice as more LEBs as the index
+ * would take if it was consolidated and written to the flash. This guarantees
+ * that the "in-the-gaps" commit method always succeeds and UBIFS will always
+ * be able to commit dirty index. So this function basically adds amount of
+ * budgeted index space to the size of the current index, multiplies this by 2,
+ * and makes sure this does not exceed the amount of free eraseblocks.
+ *
+ * Notes about @c->min_idx_lebs and @c->lst.idx_lebs variables:
+ * o @c->lst.idx_lebs is the number of LEBs the index currently uses. It might
+ * be large, because UBIFS does not do any index consolidation as long as
+ * there is free space. IOW, the index may take a lot of LEBs, but the LEBs
+ * will contain a lot of dirt.
+ * o @c->min_idx_lebs is the the index presumably takes. IOW, the index may be
+ * consolidated to take up to @c->min_idx_lebs LEBs.
+ *
+ * This function returns zero in case of success, and %-ENOSPC in case of
+ * failure.
+ */
+static int do_budget_space(struct ubifs_info *c)
+{
+ long long outstanding, available;
+ int lebs, rsvd_idx_lebs, min_idx_lebs;
+
+ /* First budget index space */
+ min_idx_lebs = ubifs_calc_min_idx_lebs(c);
+
+ /* Now 'min_idx_lebs' contains number of LEBs to reserve */
+ if (min_idx_lebs > c->lst.idx_lebs)
+ rsvd_idx_lebs = min_idx_lebs - c->lst.idx_lebs;
+ else
+ rsvd_idx_lebs = 0;
+
+ /*
+ * The number of LEBs that are available to be used by the index is:
+ *
+ * @c->lst.empty_lebs + @c->freeable_cnt + @c->idx_gc_cnt -
+ * @c->lst.taken_empty_lebs
+ *
+ * @empty_lebs are available because they are empty. @freeable_cnt are
+ * available because they contain only free and dirty space and the
+ * index allocation always occurs after wbufs are synch'ed.
+ * @idx_gc_cnt are available because they are index LEBs that have been
+ * garbage collected (including trivial GC) and are awaiting the commit
+ * before they can be unmapped - note that the in-the-gaps method will
+ * grab these if it needs them. @taken_empty_lebs are empty_lebs that
+ * have already been allocated for some purpose (also includes those
+ * LEBs on the @idx_gc list).
+ *
+ * Note, @taken_empty_lebs may temporarily be higher by one because of
+ * the way we serialize LEB allocations and budgeting. See a comment in
+ * 'ubifs_find_free_space()'.
+ */
+ lebs = c->lst.empty_lebs + c->freeable_cnt + c->idx_gc_cnt -
+ c->lst.taken_empty_lebs;
+ if (unlikely(rsvd_idx_lebs > lebs)) {
+ dbg_budg("out of indexing space: min_idx_lebs %d (old %d), "
+ "rsvd_idx_lebs %d", min_idx_lebs, c->min_idx_lebs,
+ rsvd_idx_lebs);
+ return -ENOSPC;
+ }
+
+ available = ubifs_calc_available(c, min_idx_lebs);
+ outstanding = c->budg_data_growth + c->budg_dd_growth;
+
+ if (unlikely(available < outstanding)) {
+ dbg_budg("out of data space: available %lld, outstanding %lld",
+ available, outstanding);
+ return -ENOSPC;
+ }
+
+ if (available - outstanding <= c->rp_size && !can_use_rp(c))
+ return -ENOSPC;
+
+ c->min_idx_lebs = min_idx_lebs;
+ return 0;
+}
+
+/**
+ * calc_idx_growth - calculate approximate index growth from budgeting request.
+ * @c: UBIFS file-system description object
+ * @req: budgeting request
+ *
+ * For now we assume each new node adds one znode. But this is rather poor
+ * approximation, though.
+ */
+static int calc_idx_growth(const struct ubifs_info *c,
+ const struct ubifs_budget_req *req)
+{
+ int znodes;
+
+ znodes = req->new_ino + (req->new_page << UBIFS_BLOCKS_PER_PAGE_SHIFT) +
+ req->new_dent;
+ return znodes * c->max_idx_node_sz;
+}
+
+/**
+ * calc_data_growth - calculate approximate amount of new data from budgeting
+ * request.
+ * @c: UBIFS file-system description object
+ * @req: budgeting request
+ */
+static int calc_data_growth(const struct ubifs_info *c,
+ const struct ubifs_budget_req *req)
+{
+ int data_growth;
+
+ data_growth = req->new_ino ? c->inode_budget : 0;
+ if (req->new_page)
+ data_growth += c->page_budget;
+ if (req->new_dent)
+ data_growth += c->dent_budget;
+ data_growth += req->new_ino_d;
+ return data_growth;
+}
+
+/**
+ * calc_dd_growth - calculate approximate amount of data which makes other data
+ * dirty from budgeting request.
+ * @c: UBIFS file-system description object
+ * @req: budgeting request
+ */
+static int calc_dd_growth(const struct ubifs_info *c,
+ const struct ubifs_budget_req *req)
+{
+ int dd_growth;
+
+ dd_growth = req->dirtied_page ? c->page_budget : 0;
+
+ if (req->dirtied_ino)
+ dd_growth += c->inode_budget << (req->dirtied_ino - 1);
+ if (req->mod_dent)
+ dd_growth += c->dent_budget;
+ dd_growth += req->dirtied_ino_d;
+ return dd_growth;
+}
+
+/**
+ * ubifs_budget_space - ensure there is enough space to complete an operation.
+ * @c: UBIFS file-system description object
+ * @req: budget request
+ *
+ * This function allocates budget for an operation. It uses pessimistic
+ * approximation of how much flash space the operation needs. The goal of this
+ * function is to make sure UBIFS always has flash space to flush all dirty
+ * pages, dirty inodes, and dirty znodes (liability). This function may force
+ * commit, garbage-collection or write-back. Returns zero in case of success,
+ * %-ENOSPC if there is no free space and other negative error codes in case of
+ * failures.
+ */
+int ubifs_budget_space(struct ubifs_info *c, struct ubifs_budget_req *req)
+{
+ int uninitialized_var(cmt_retries), uninitialized_var(wb_retries);
+ int err, idx_growth, data_growth, dd_growth;
+ struct retries_info ri;
+
+ ubifs_assert(req->dirtied_ino <= 4);
+ ubifs_assert(req->dirtied_ino_d <= UBIFS_MAX_INO_DATA * 4);
+
+ data_growth = calc_data_growth(c, req);
+ dd_growth = calc_dd_growth(c, req);
+ if (!data_growth && !dd_growth)
+ return 0;
+ idx_growth = calc_idx_growth(c, req);
+ memset(&ri, 0, sizeof(struct retries_info));
+
+again:
+ spin_lock(&c->space_lock);
+ ubifs_assert(c->budg_idx_growth >= 0);
+ ubifs_assert(c->budg_data_growth >= 0);
+ ubifs_assert(c->budg_dd_growth >= 0);
+
+ if (unlikely(c->nospace) && (c->nospace_rp || !can_use_rp(c))) {
+ dbg_budg("no space");
+ spin_unlock(&c->space_lock);
+ return -ENOSPC;
+ }
+
+ c->budg_idx_growth += idx_growth;
+ c->budg_data_growth += data_growth;
+ c->budg_dd_growth += dd_growth;
+
+ err = do_budget_space(c);
+ if (likely(!err)) {
+ req->idx_growth = idx_growth;
+ req->data_growth = data_growth;
+ req->dd_growth = dd_growth;
+ spin_unlock(&c->space_lock);
+ return 0;
+ }
+
+ /* Restore the old values */
+ c->budg_idx_growth -= idx_growth;
+ c->budg_data_growth -= data_growth;
+ c->budg_dd_growth -= dd_growth;
+ spin_unlock(&c->space_lock);
+
+ if (req->fast) {
+ dbg_budg("no space for fast budgeting");
+ return err;
+ }
+
+ err = make_free_space(c, &ri);
+ if (err == -EAGAIN) {
+ dbg_budg("try again");
+ cond_resched();
+ goto again;
+ } else if (err == -ENOSPC) {
+ dbg_budg("FS is full, -ENOSPC");
+ c->nospace = 1;
+ if (can_use_rp(c) || c->rp_size == 0)
+ c->nospace_rp = 1;
+ smp_wmb();
+ } else
+ ubifs_err("cannot budget space, error %d", err);
+ return err;
+}
+
+/**
+ * ubifs_release_budget - release budgeted free space.
+ * @c: UBIFS file-system description object
+ * @req: budget request
+ *
+ * This function releases the space budgeted by 'ubifs_budget_space()'. Note,
+ * since the index changes (which were budgeted for in @req->idx_growth) will
+ * only be written to the media on commit, this function moves the index budget
+ * from @c->budg_idx_growth to @c->budg_uncommitted_idx. The latter will be
+ * zeroed by the commit operation.
+ */
+void ubifs_release_budget(struct ubifs_info *c, struct ubifs_budget_req *req)
+{
+ ubifs_assert(req->dirtied_ino <= 4);
+ ubifs_assert(req->dirtied_ino_d <= UBIFS_MAX_INO_DATA * 4);
+ if (!req->recalculate) {
+ ubifs_assert(req->idx_growth >= 0);
+ ubifs_assert(req->data_growth >= 0);
+ ubifs_assert(req->dd_growth >= 0);
+ }
+
+ if (req->recalculate) {
+ req->data_growth = calc_data_growth(c, req);
+ req->dd_growth = calc_dd_growth(c, req);
+ req->idx_growth = calc_idx_growth(c, req);
+ }
+
+ if (!req->data_growth && !req->dd_growth)
+ return;
+
+ c->nospace = c->nospace_rp = 0;
+ smp_wmb();
+
+ spin_lock(&c->space_lock);
+ c->budg_idx_growth -= req->idx_growth;
+ c->budg_uncommitted_idx += req->idx_growth;
+ c->budg_data_growth -= req->data_growth;
+ c->budg_dd_growth -= req->dd_growth;
+ c->min_idx_lebs = ubifs_calc_min_idx_lebs(c);
+
+ ubifs_assert(c->budg_idx_growth >= 0);
+ ubifs_assert(c->budg_data_growth >= 0);
+ ubifs_assert(c->min_idx_lebs < c->main_lebs);
+ spin_unlock(&c->space_lock);
+}
+
+/**
+ * ubifs_convert_page_budget - convert budget of a new page.
+ * @c: UBIFS file-system description object
+ *
+ * This function converts budget which was allocated for a new page of data to
+ * the budget of changing an existing page of data. The latter is smaller then
+ * the former, so this function only does simple re-calculation and does not
+ * involve any write-back.
+ */
+void ubifs_convert_page_budget(struct ubifs_info *c)
+{
+ spin_lock(&c->space_lock);
+ /* Release the index growth reservation */
+ c->budg_idx_growth -= c->max_idx_node_sz << UBIFS_BLOCKS_PER_PAGE_SHIFT;
+ /* Release the data growth reservation */
+ c->budg_data_growth -= c->page_budget;
+ /* Increase the dirty data growth reservation instead */
+ c->budg_dd_growth += c->page_budget;
+ /* And re-calculate the indexing space reservation */
+ c->min_idx_lebs = ubifs_calc_min_idx_lebs(c);
+ spin_unlock(&c->space_lock);
+}
+
+/**
+ * ubifs_release_dirty_inode_budget - release dirty inode budget.
+ * @c: UBIFS file-system description object
+ * @ui: UBIFS inode to release the budget for
+ *
+ * This function releases budget corresponding to a dirty inode. It is usually
+ * called when after the inode has been written to the media and marked as
+ * clean.
+ */
+void ubifs_release_dirty_inode_budget(struct ubifs_info *c,
+ struct ubifs_inode *ui)
+{
+ struct ubifs_budget_req req = {.dd_growth = c->inode_budget,
+ .dirtied_ino_d = ui->data_len};
+
+ ubifs_release_budget(c, &req);
+}
+
+/**
+ * ubifs_budg_get_free_space - return amount of free space.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns amount of free space on the file-system.
+ */
+long long ubifs_budg_get_free_space(struct ubifs_info *c)
+{
+ int min_idx_lebs, rsvd_idx_lebs;
+ long long available, outstanding, free;
+
+ /* Do exactly the same calculations as in 'do_budget_space()' */
+ spin_lock(&c->space_lock);
+ min_idx_lebs = ubifs_calc_min_idx_lebs(c);
+
+ if (min_idx_lebs > c->lst.idx_lebs)
+ rsvd_idx_lebs = min_idx_lebs - c->lst.idx_lebs;
+ else
+ rsvd_idx_lebs = 0;
+
+ if (rsvd_idx_lebs > c->lst.empty_lebs + c->freeable_cnt + c->idx_gc_cnt
+ - c->lst.taken_empty_lebs) {
+ spin_unlock(&c->space_lock);
+ return 0;
+ }
+
+ available = ubifs_calc_available(c, min_idx_lebs);
+ outstanding = c->budg_data_growth + c->budg_dd_growth;
+ c->min_idx_lebs = min_idx_lebs;
+ spin_unlock(&c->space_lock);
+
+ if (available > outstanding)
+ free = ubifs_reported_space(c, available - outstanding);
+ else
+ free = 0;
+ return free;
+}
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ * Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file implements functions that manage the running of the commit process.
+ * Each affected module has its own functions to accomplish their part in the
+ * commit and those functions are called here.
+ *
+ * The commit is the process whereby all updates to the index and LEB properties
+ * are written out together and the journal becomes empty. This keeps the
+ * file system consistent - at all times the state can be recreated by reading
+ * the index and LEB properties and then replaying the journal.
+ *
+ * The commit is split into two parts named "commit start" and "commit end".
+ * During commit start, the commit process has exclusive access to the journal
+ * by holding the commit semaphore down for writing. As few I/O operations as
+ * possible are performed during commit start, instead the nodes that are to be
+ * written are merely identified. During commit end, the commit semaphore is no
+ * longer held and the journal is again in operation, allowing users to continue
+ * to use the file system while the bulk of the commit I/O is performed. The
+ * purpose of this two-step approach is to prevent the commit from causing any
+ * latency blips. Note that in any case, the commit does not prevent lookups
+ * (as permitted by the TNC mutex), or access to VFS data structures e.g. page
+ * cache.
+ */
+
+#include <linux/freezer.h>
+#include <linux/kthread.h>
+#include "ubifs.h"
+
+/**
+ * do_commit - commit the journal.
+ * @c: UBIFS file-system description object
+ *
+ * This function implements UBIFS commit. It has to be called with commit lock
+ * locked. Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+static int do_commit(struct ubifs_info *c)
+{
+ int err, new_ltail_lnum, old_ltail_lnum, i;
+ struct ubifs_zbranch zroot;
+ struct ubifs_lp_stats lst;
+
+ dbg_cmt("start");
+ if (c->ro_media) {
+ err = -EROFS;
+ goto out_up;
+ }
+
+ /* Sync all write buffers (necessary for recovery) */
+ for (i = 0; i < c->jhead_cnt; i++) {
+ err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
+ if (err)
+ goto out_up;
+ }
+
+ err = ubifs_gc_start_commit(c);
+ if (err)
+ goto out_up;
+ err = dbg_check_lprops(c);
+ if (err)
+ goto out_up;
+ err = ubifs_log_start_commit(c, &new_ltail_lnum);
+ if (err)
+ goto out_up;
+ err = ubifs_tnc_start_commit(c, &zroot);
+ if (err)
+ goto out_up;
+ err = ubifs_lpt_start_commit(c);
+ if (err)
+ goto out_up;
+ err = ubifs_orphan_start_commit(c);
+ if (err)
+ goto out_up;
+
+ ubifs_get_lp_stats(c, &lst);
+
+ up_write(&c->commit_sem);
+
+ err = ubifs_tnc_end_commit(c);
+ if (err)
+ goto out;
+ err = ubifs_lpt_end_commit(c);
+ if (err)
+ goto out;
+ err = ubifs_orphan_end_commit(c);
+ if (err)
+ goto out;
+ old_ltail_lnum = c->ltail_lnum;
+ err = ubifs_log_end_commit(c, new_ltail_lnum);
+ if (err)
+ goto out;
+ err = dbg_check_old_index(c, &zroot);
+ if (err)
+ goto out;
+
+ mutex_lock(&c->mst_mutex);
+ c->mst_node->cmt_no = cpu_to_le64(++c->cmt_no);
+ c->mst_node->log_lnum = cpu_to_le32(new_ltail_lnum);
+ c->mst_node->root_lnum = cpu_to_le32(zroot.lnum);
+ c->mst_node->root_offs = cpu_to_le32(zroot.offs);
+ c->mst_node->root_len = cpu_to_le32(zroot.len);
+ c->mst_node->ihead_lnum = cpu_to_le32(c->ihead_lnum);
+ c->mst_node->ihead_offs = cpu_to_le32(c->ihead_offs);
+ c->mst_node->index_size = cpu_to_le64(c->old_idx_sz);
+ c->mst_node->lpt_lnum = cpu_to_le32(c->lpt_lnum);
+ c->mst_node->lpt_offs = cpu_to_le32(c->lpt_offs);
+ c->mst_node->nhead_lnum = cpu_to_le32(c->nhead_lnum);
+ c->mst_node->nhead_offs = cpu_to_le32(c->nhead_offs);
+ c->mst_node->ltab_lnum = cpu_to_le32(c->ltab_lnum);
+ c->mst_node->ltab_offs = cpu_to_le32(c->ltab_offs);
+ c->mst_node->lsave_lnum = cpu_to_le32(c->lsave_lnum);
+ c->mst_node->lsave_offs = cpu_to_le32(c->lsave_offs);
+ c->mst_node->lscan_lnum = cpu_to_le32(c->lscan_lnum);
+ c->mst_node->empty_lebs = cpu_to_le32(lst.empty_lebs);
+ c->mst_node->idx_lebs = cpu_to_le32(lst.idx_lebs);
+ c->mst_node->total_free = cpu_to_le64(lst.total_free);
+ c->mst_node->total_dirty = cpu_to_le64(lst.total_dirty);
+ c->mst_node->total_used = cpu_to_le64(lst.total_used);
+ c->mst_node->total_dead = cpu_to_le64(lst.total_dead);
+ c->mst_node->total_dark = cpu_to_le64(lst.total_dark);
+ if (c->no_orphs)
+ c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS);
+ else
+ c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_NO_ORPHS);
+ err = ubifs_write_master(c);
+ mutex_unlock(&c->mst_mutex);
+ if (err)
+ goto out;
+
+ err = ubifs_log_post_commit(c, old_ltail_lnum);
+ if (err)
+ goto out;
+ err = ubifs_gc_end_commit(c);
+ if (err)
+ goto out;
+ err = ubifs_lpt_post_commit(c);
+ if (err)
+ goto out;
+
+ spin_lock(&c->cs_lock);
+ c->cmt_state = COMMIT_RESTING;
+ wake_up(&c->cmt_wq);
+ dbg_cmt("commit end");
+ spin_unlock(&c->cs_lock);
+
+ return 0;
+
+out_up:
+ up_write(&c->commit_sem);
+out:
+ ubifs_err("commit failed, error %d", err);
+ spin_lock(&c->cs_lock);
+ c->cmt_state = COMMIT_BROKEN;
+ wake_up(&c->cmt_wq);
+ spin_unlock(&c->cs_lock);
+ ubifs_ro_mode(c, err);
+ return err;
+}
+
+/**
+ * run_bg_commit - run background commit if it is needed.
+ * @c: UBIFS file-system description object
+ *
+ * This function runs background commit if it is needed. Returns zero in case
+ * of success and a negative error code in case of failure.
+ */
+static int run_bg_commit(struct ubifs_info *c)
+{
+ spin_lock(&c->cs_lock);
+ /*
+ * Run background commit only if background commit was requested or if
+ * commit is required.
+ */
+ if (c->cmt_state != COMMIT_BACKGROUND &&
+ c->cmt_state != COMMIT_REQUIRED)
+ goto out;
+ spin_unlock(&c->cs_lock);
+
+ down_write(&c->commit_sem);
+ spin_lock(&c->cs_lock);
+ if (c->cmt_state == COMMIT_REQUIRED)
+ c->cmt_state = COMMIT_RUNNING_REQUIRED;
+ else if (c->cmt_state == COMMIT_BACKGROUND)
+ c->cmt_state = COMMIT_RUNNING_BACKGROUND;
+ else
+ goto out_cmt_unlock;
+ spin_unlock(&c->cs_lock);
+
+ return do_commit(c);
+
+out_cmt_unlock:
+ up_write(&c->commit_sem);
+out:
+ spin_unlock(&c->cs_lock);
+ return 0;
+}
+
+/**
+ * ubifs_bg_thread - UBIFS background thread function.
+ * @info: points to the file-system description object
+ *
+ * This function implements various file-system background activities:
+ * o when a write-buffer timer expires it synchronizes the appropriate
+ * write-buffer;
+ * o when the journal is about to be full, it starts in-advance commit.
+ *
+ * Note, other stuff like background garbage collection may be added here in
+ * future.
+ */
+int ubifs_bg_thread(void *info)
+{
+ int err;
+ struct ubifs_info *c = info;
+
+ ubifs_msg("background thread \"%s\" started, PID %d",
+ c->bgt_name, current->pid);
+ set_freezable();
+
+ while (1) {
+ if (kthread_should_stop())
+ break;
+
+ if (try_to_freeze())
+ continue;
+
+ set_current_state(TASK_INTERRUPTIBLE);
+ /* Check if there is something to do */
+ if (!c->need_bgt) {
+ /*
+ * Nothing prevents us from going sleep now and
+ * be never woken up and block the task which
+ * could wait in 'kthread_stop()' forever.
+ */
+ if (kthread_should_stop())
+ break;
+ schedule();
+ continue;
+ } else
+ __set_current_state(TASK_RUNNING);
+
+ c->need_bgt = 0;
+ err = ubifs_bg_wbufs_sync(c);
+ if (err)
+ ubifs_ro_mode(c, err);
+
+ run_bg_commit(c);
+ cond_resched();
+ }
+
+ dbg_msg("background thread \"%s\" stops", c->bgt_name);
+ return 0;
+}
+
+/**
+ * ubifs_commit_required - set commit state to "required".
+ * @c: UBIFS file-system description object
+ *
+ * This function is called if a commit is required but cannot be done from the
+ * calling function, so it is just flagged instead.
+ */
+void ubifs_commit_required(struct ubifs_info *c)
+{
+ spin_lock(&c->cs_lock);
+ switch (c->cmt_state) {
+ case COMMIT_RESTING:
+ case COMMIT_BACKGROUND:
+ dbg_cmt("old: %s, new: %s", dbg_cstate(c->cmt_state),
+ dbg_cstate(COMMIT_REQUIRED));
+ c->cmt_state = COMMIT_REQUIRED;
+ break;
+ case COMMIT_RUNNING_BACKGROUND:
+ dbg_cmt("old: %s, new: %s", dbg_cstate(c->cmt_state),
+ dbg_cstate(COMMIT_RUNNING_REQUIRED));
+ c->cmt_state = COMMIT_RUNNING_REQUIRED;
+ break;
+ case COMMIT_REQUIRED:
+ case COMMIT_RUNNING_REQUIRED:
+ case COMMIT_BROKEN:
+ break;
+ }
+ spin_unlock(&c->cs_lock);
+}
+
+/**
+ * ubifs_request_bg_commit - notify the background thread to do a commit.
+ * @c: UBIFS file-system description object
+ *
+ * This function is called if the journal is full enough to make a commit
+ * worthwhile, so background thread is kicked to start it.
+ */
+void ubifs_request_bg_commit(struct ubifs_info *c)
+{
+ spin_lock(&c->cs_lock);
+ if (c->cmt_state == COMMIT_RESTING) {
+ dbg_cmt("old: %s, new: %s", dbg_cstate(c->cmt_state),
+ dbg_cstate(COMMIT_BACKGROUND));
+ c->cmt_state = COMMIT_BACKGROUND;
+ spin_unlock(&c->cs_lock);
+ ubifs_wake_up_bgt(c);
+ } else
+ spin_unlock(&c->cs_lock);
+}
+
+/**
+ * wait_for_commit - wait for commit.
+ * @c: UBIFS file-system description object
+ *
+ * This function sleeps until the commit operation is no longer running.
+ */
+static int wait_for_commit(struct ubifs_info *c)
+{
+ dbg_cmt("pid %d goes sleep", current->pid);
+
+ /*
+ * The following sleeps if the condition is false, and will be woken
+ * when the commit ends. It is possible, although very unlikely, that we
+ * will wake up and see the subsequent commit running, rather than the
+ * one we were waiting for, and go back to sleep. However, we will be
+ * woken again, so there is no danger of sleeping forever.
+ */
+ wait_event(c->cmt_wq, c->cmt_state != COMMIT_RUNNING_BACKGROUND &&
+ c->cmt_state != COMMIT_RUNNING_REQUIRED);
+ dbg_cmt("commit finished, pid %d woke up", current->pid);
+ return 0;
+}
+
+/**
+ * ubifs_run_commit - run or wait for commit.
+ * @c: UBIFS file-system description object
+ *
+ * This function runs commit and returns zero in case of success and a negative
+ * error code in case of failure.
+ */
+int ubifs_run_commit(struct ubifs_info *c)
+{
+ int err = 0;
+
+ spin_lock(&c->cs_lock);
+ if (c->cmt_state == COMMIT_BROKEN) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ if (c->cmt_state == COMMIT_RUNNING_BACKGROUND)
+ /*
+ * We set the commit state to 'running required' to indicate
+ * that we want it to complete as quickly as possible.
+ */
+ c->cmt_state = COMMIT_RUNNING_REQUIRED;
+
+ if (c->cmt_state == COMMIT_RUNNING_REQUIRED) {
+ spin_unlock(&c->cs_lock);
+ return wait_for_commit(c);
+ }
+ spin_unlock(&c->cs_lock);
+
+ /* Ok, the commit is indeed needed */
+
+ down_write(&c->commit_sem);
+ spin_lock(&c->cs_lock);
+ /*
+ * Since we unlocked 'c->cs_lock', the state may have changed, so
+ * re-check it.
+ */
+ if (c->cmt_state == COMMIT_BROKEN) {
+ err = -EINVAL;
+ goto out_cmt_unlock;
+ }
+
+ if (c->cmt_state == COMMIT_RUNNING_BACKGROUND)
+ c->cmt_state = COMMIT_RUNNING_REQUIRED;
+
+ if (c->cmt_state == COMMIT_RUNNING_REQUIRED) {
+ up_write(&c->commit_sem);
+ spin_unlock(&c->cs_lock);
+ return wait_for_commit(c);
+ }
+ c->cmt_state = COMMIT_RUNNING_REQUIRED;
+ spin_unlock(&c->cs_lock);
+
+ err = do_commit(c);
+ return err;
+
+out_cmt_unlock:
+ up_write(&c->commit_sem);
+out:
+ spin_unlock(&c->cs_lock);
+ return err;
+}
+
+/**
+ * ubifs_gc_should_commit - determine if it is time for GC to run commit.
+ * @c: UBIFS file-system description object
+ *
+ * This function is called by garbage collection to determine if commit should
+ * be run. If commit state is @COMMIT_BACKGROUND, which means that the journal
+ * is full enough to start commit, this function returns true. It is not
+ * absolutely necessary to commit yet, but it feels like this should be better
+ * then to keep doing GC. This function returns %1 if GC has to initiate commit
+ * and %0 if not.
+ */
+int ubifs_gc_should_commit(struct ubifs_info *c)
+{
+ int ret = 0;
+
+ spin_lock(&c->cs_lock);
+ if (c->cmt_state == COMMIT_BACKGROUND) {
+ dbg_cmt("commit required now");
+ c->cmt_state = COMMIT_REQUIRED;
+ } else
+ dbg_cmt("commit not requested");
+ if (c->cmt_state == COMMIT_REQUIRED)
+ ret = 1;
+ spin_unlock(&c->cs_lock);
+ return ret;
+}
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+
+/**
+ * struct idx_node - hold index nodes during index tree traversal.
+ * @list: list
+ * @iip: index in parent (slot number of this indexing node in the parent
+ * indexing node)
+ * @upper_key: all keys in this indexing node have to be less or equivalent to
+ * this key
+ * @idx: index node (8-byte aligned because all node structures must be 8-byte
+ * aligned)
+ */
+struct idx_node {
+ struct list_head list;
+ int iip;
+ union ubifs_key upper_key;
+ struct ubifs_idx_node idx __attribute__((aligned(8)));
+};
+
+/**
+ * dbg_old_index_check_init - get information for the next old index check.
+ * @c: UBIFS file-system description object
+ * @zroot: root of the index
+ *
+ * This function records information about the index that will be needed for the
+ * next old index check i.e. 'dbg_check_old_index()'.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int dbg_old_index_check_init(struct ubifs_info *c, struct ubifs_zbranch *zroot)
+{
+ struct ubifs_idx_node *idx;
+ int lnum, offs, len, err = 0;
+
+ c->old_zroot = *zroot;
+
+ lnum = c->old_zroot.lnum;
+ offs = c->old_zroot.offs;
+ len = c->old_zroot.len;
+
+ idx = kmalloc(c->max_idx_node_sz, GFP_NOFS);
+ if (!idx)
+ return -ENOMEM;
+
+ err = ubifs_read_node(c, idx, UBIFS_IDX_NODE, len, lnum, offs);
+ if (err)
+ goto out;
+
+ c->old_zroot_level = le16_to_cpu(idx->level);
+ c->old_zroot_sqnum = le64_to_cpu(idx->ch.sqnum);
+out:
+ kfree(idx);
+ return err;
+}
+
+/**
+ * dbg_check_old_index - check the old copy of the index.
+ * @c: UBIFS file-system description object
+ * @zroot: root of the new index
+ *
+ * In order to be able to recover from an unclean unmount, a complete copy of
+ * the index must exist on flash. This is the "old" index. The commit process
+ * must write the "new" index to flash without overwriting or destroying any
+ * part of the old index. This function is run at commit end in order to check
+ * that the old index does indeed exist completely intact.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int dbg_check_old_index(struct ubifs_info *c, struct ubifs_zbranch *zroot)
+{
+ int lnum, offs, len, err = 0, uninitialized_var(last_level), child_cnt;
+ int first = 1, iip;
+ union ubifs_key lower_key, upper_key, l_key, u_key;
+ unsigned long long uninitialized_var(last_sqnum);
+ struct ubifs_idx_node *idx;
+ struct list_head list;
+ struct idx_node *i;
+ size_t sz;
+
+ if (!(ubifs_chk_flags & UBIFS_CHK_OLD_IDX))
+ goto out;
+
+ INIT_LIST_HEAD(&list);
+
+ sz = sizeof(struct idx_node) + ubifs_idx_node_sz(c, c->fanout) -
+ UBIFS_IDX_NODE_SZ;
+
+ /* Start at the old zroot */
+ lnum = c->old_zroot.lnum;
+ offs = c->old_zroot.offs;
+ len = c->old_zroot.len;
+ iip = 0;
+
+ /*
+ * Traverse the index tree preorder depth-first i.e. do a node and then
+ * its subtrees from left to right.
+ */
+ while (1) {
+ struct ubifs_branch *br;
+
+ /* Get the next index node */
+ i = kmalloc(sz, GFP_NOFS);
+ if (!i) {
+ err = -ENOMEM;
+ goto out_free;
+ }
+ i->iip = iip;
+ /* Keep the index nodes on our path in a linked list */
+ list_add_tail(&i->list, &list);
+ /* Read the index node */
+ idx = &i->idx;
+ err = ubifs_read_node(c, idx, UBIFS_IDX_NODE, len, lnum, offs);
+ if (err)
+ goto out_free;
+ /* Validate index node */
+ child_cnt = le16_to_cpu(idx->child_cnt);
+ if (child_cnt < 1 || child_cnt > c->fanout) {
+ err = 1;
+ goto out_dump;
+ }
+ if (first) {
+ first = 0;
+ /* Check root level and sqnum */
+ if (le16_to_cpu(idx->level) != c->old_zroot_level) {
+ err = 2;
+ goto out_dump;
+ }
+ if (le64_to_cpu(idx->ch.sqnum) != c->old_zroot_sqnum) {
+ err = 3;
+ goto out_dump;
+ }
+ /* Set last values as though root had a parent */
+ last_level = le16_to_cpu(idx->level) + 1;
+ last_sqnum = le64_to_cpu(idx->ch.sqnum) + 1;
+ key_read(c, ubifs_idx_key(c, idx), &lower_key);
+ highest_ino_key(c, &upper_key, INUM_WATERMARK);
+ }
+ key_copy(c, &upper_key, &i->upper_key);
+ if (le16_to_cpu(idx->level) != last_level - 1) {
+ err = 3;
+ goto out_dump;
+ }
+ /*
+ * The index is always written bottom up hence a child's sqnum
+ * is always less than the parents.
+ */
+ if (le64_to_cpu(idx->ch.sqnum) >= last_sqnum) {
+ err = 4;
+ goto out_dump;
+ }
+ /* Check key range */
+ key_read(c, ubifs_idx_key(c, idx), &l_key);
+ br = ubifs_idx_branch(c, idx, child_cnt - 1);
+ key_read(c, &br->key, &u_key);
+ if (keys_cmp(c, &lower_key, &l_key) > 0) {
+ err = 5;
+ goto out_dump;
+ }
+ if (keys_cmp(c, &upper_key, &u_key) < 0) {
+ err = 6;
+ goto out_dump;
+ }
+ if (keys_cmp(c, &upper_key, &u_key) == 0)
+ if (!is_hash_key(c, &u_key)) {
+ err = 7;
+ goto out_dump;
+ }
+ /* Go to next index node */
+ if (le16_to_cpu(idx->level) == 0) {
+ /* At the bottom, so go up until can go right */
+ while (1) {
+ /* Drop the bottom of the list */
+ list_del(&i->list);
+ kfree(i);
+ /* No more list means we are done */
+ if (list_empty(&list))
+ goto out;
+ /* Look at the new bottom */
+ i = list_entry(list.prev, struct idx_node,
+ list);
+ idx = &i->idx;
+ /* Can we go right */
+ if (iip + 1 < le16_to_cpu(idx->child_cnt)) {
+ iip = iip + 1;
+ break;
+ } else
+ /* Nope, so go up again */
+ iip = i->iip;
+ }
+ } else
+ /* Go down left */
+ iip = 0;
+ /*
+ * We have the parent in 'idx' and now we set up for reading the
+ * child pointed to by slot 'iip'.
+ */
+ last_level = le16_to_cpu(idx->level);
+ last_sqnum = le64_to_cpu(idx->ch.sqnum);
+ br = ubifs_idx_branch(c, idx, iip);
+ lnum = le32_to_cpu(br->lnum);
+ offs = le32_to_cpu(br->offs);
+ len = le32_to_cpu(br->len);
+ key_read(c, &br->key, &lower_key);
+ if (iip + 1 < le16_to_cpu(idx->child_cnt)) {
+ br = ubifs_idx_branch(c, idx, iip + 1);
+ key_read(c, &br->key, &upper_key);
+ } else
+ key_copy(c, &i->upper_key, &upper_key);
+ }
+out:
+ err = dbg_old_index_check_init(c, zroot);
+ if (err)
+ goto out_free;
+
+ return 0;
+
+out_dump:
+ dbg_err("dumping index node (iip=%d)", i->iip);
+ dbg_dump_node(c, idx);
+ list_del(&i->list);
+ kfree(i);
+ if (!list_empty(&list)) {
+ i = list_entry(list.prev, struct idx_node, list);
+ dbg_err("dumping parent index node");
+ dbg_dump_node(c, &i->idx);
+ }
+out_free:
+ while (!list_empty(&list)) {
+ i = list_entry(list.next, struct idx_node, list);
+ list_del(&i->list);
+ kfree(i);
+ }
+ ubifs_err("failed, error %d", err);
+ if (err > 0)
+ err = -EINVAL;
+ return err;
+}
+
+#endif /* CONFIG_UBIFS_FS_DEBUG */
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ * Copyright (C) 2006, 2007 University of Szeged, Hungary
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ * Artem Bityutskiy (Битюцкий Артём)
+ * Zoltan Sogor
+ */
+
+/*
+ * This file provides a single place to access to compression and
+ * decompression.
+ */
+
+#include <linux/crypto.h>
+#include "ubifs.h"
+
+/* Fake description object for the "none" compressor */
+static struct ubifs_compressor none_compr = {
+ .compr_type = UBIFS_COMPR_NONE,
+ .name = "no compression",
+ .capi_name = "",
+};
+
+#ifdef CONFIG_UBIFS_FS_LZO
+static DEFINE_MUTEX(lzo_mutex);
+
+static struct ubifs_compressor lzo_compr = {
+ .compr_type = UBIFS_COMPR_LZO,
+ .comp_mutex = &lzo_mutex,
+ .name = "LZO",
+ .capi_name = "lzo",
+};
+#else
+static struct ubifs_compressor lzo_compr = {
+ .compr_type = UBIFS_COMPR_LZO,
+ .name = "LZO",
+};
+#endif
+
+#ifdef CONFIG_UBIFS_FS_ZLIB
+static DEFINE_MUTEX(deflate_mutex);
+static DEFINE_MUTEX(inflate_mutex);
+
+static struct ubifs_compressor zlib_compr = {
+ .compr_type = UBIFS_COMPR_ZLIB,
+ .comp_mutex = &deflate_mutex,
+ .decomp_mutex = &inflate_mutex,
+ .name = "zlib",
+ .capi_name = "deflate",
+};
+#else
+static struct ubifs_compressor zlib_compr = {
+ .compr_type = UBIFS_COMPR_ZLIB,
+ .name = "zlib",
+};
+#endif
+
+/* All UBIFS compressors */
+struct ubifs_compressor *ubifs_compressors[UBIFS_COMPR_TYPES_CNT];
+
+/**
+ * ubifs_compress - compress data.
+ * @in_buf: data to compress
+ * @in_len: length of the data to compress
+ * @out_buf: output buffer where compressed data should be stored
+ * @out_len: output buffer length is returned here
+ * @compr_type: type of compression to use on enter, actually used compression
+ * type on exit
+ *
+ * This function compresses input buffer @in_buf of length @in_len and stores
+ * the result in the output buffer @out_buf and the resulting length in
+ * @out_len. If the input buffer does not compress, it is just copied to the
+ * @out_buf. The same happens if @compr_type is %UBIFS_COMPR_NONE or if
+ * compression error occurred.
+ *
+ * Note, if the input buffer was not compressed, it is copied to the output
+ * buffer and %UBIFS_COMPR_NONE is returned in @compr_type.
+ *
+ * This functions returns %0 on success or a negative error code on failure.
+ */
+void ubifs_compress(const void *in_buf, int in_len, void *out_buf, int *out_len,
+ int *compr_type)
+{
+ int err;
+ struct ubifs_compressor *compr = ubifs_compressors[*compr_type];
+
+ if (*compr_type == UBIFS_COMPR_NONE)
+ goto no_compr;
+
+ /* If the input data is small, do not even try to compress it */
+ if (in_len < UBIFS_MIN_COMPR_LEN)
+ goto no_compr;
+
+ if (compr->comp_mutex)
+ mutex_lock(compr->comp_mutex);
+ err = crypto_comp_compress(compr->cc, in_buf, in_len, out_buf,
+ out_len);
+ if (compr->comp_mutex)
+ mutex_unlock(compr->comp_mutex);
+ if (unlikely(err)) {
+ ubifs_warn("cannot compress %d bytes, compressor %s, "
+ "error %d, leave data uncompressed",
+ in_len, compr->name, err);
+ goto no_compr;
+ }
+
+ /*
+ * Presently, we just require that compression results in less data,
+ * rather than any defined minimum compression ratio or amount.
+ */
+ if (ALIGN(*out_len, 8) >= ALIGN(in_len, 8))
+ goto no_compr;
+
+ return;
+
+no_compr:
+ memcpy(out_buf, in_buf, in_len);
+ *out_len = in_len;
+ *compr_type = UBIFS_COMPR_NONE;
+}
+
+/**
+ * ubifs_decompress - decompress data.
+ * @in_buf: data to decompress
+ * @in_len: length of the data to decompress
+ * @out_buf: output buffer where decompressed data should
+ * @out_len: output length is returned here
+ * @compr_type: type of compression
+ *
+ * This function decompresses data from buffer @in_buf into buffer @out_buf.
+ * The length of the uncompressed data is returned in @out_len. This functions
+ * returns %0 on success or a negative error code on failure.
+ */
+int ubifs_decompress(const void *in_buf, int in_len, void *out_buf,
+ int *out_len, int compr_type)
+{
+ int err;
+ struct ubifs_compressor *compr;
+
+ if (unlikely(compr_type < 0 || compr_type >= UBIFS_COMPR_TYPES_CNT)) {
+ ubifs_err("invalid compression type %d", compr_type);
+ return -EINVAL;
+ }
+
+ compr = ubifs_compressors[compr_type];
+
+ if (unlikely(!compr->capi_name)) {
+ ubifs_err("%s compression is not compiled in", compr->name);
+ return -EINVAL;
+ }
+
+ if (compr_type == UBIFS_COMPR_NONE) {
+ memcpy(out_buf, in_buf, in_len);
+ *out_len = in_len;
+ return 0;
+ }
+
+ if (compr->decomp_mutex)
+ mutex_lock(compr->decomp_mutex);
+ err = crypto_comp_decompress(compr->cc, in_buf, in_len, out_buf,
+ out_len);
+ if (compr->decomp_mutex)
+ mutex_unlock(compr->decomp_mutex);
+ if (err)
+ ubifs_err("cannot decompress %d bytes, compressor %s, "
+ "error %d", in_len, compr->name, err);
+
+ return err;
+}
+
+/**
+ * compr_init - initialize a compressor.
+ * @compr: compressor description object
+ *
+ * This function initializes the requested compressor and returns zero in case
+ * of success or a negative error code in case of failure.
+ */
+static int __init compr_init(struct ubifs_compressor *compr)
+{
+ if (compr->capi_name) {
+ compr->cc = crypto_alloc_comp(compr->capi_name, 0, 0);
+ if (IS_ERR(compr->cc)) {
+ ubifs_err("cannot initialize compressor %s, error %ld",
+ compr->name, PTR_ERR(compr->cc));
+ return PTR_ERR(compr->cc);
+ }
+ }
+
+ ubifs_compressors[compr->compr_type] = compr;
+ return 0;
+}
+
+/**
+ * compr_exit - de-initialize a compressor.
+ * @compr: compressor description object
+ */
+static void compr_exit(struct ubifs_compressor *compr)
+{
+ if (compr->capi_name)
+ crypto_free_comp(compr->cc);
+ return;
+}
+
+/**
+ * ubifs_compressors_init - initialize UBIFS compressors.
+ *
+ * This function initializes the compressor which were compiled in. Returns
+ * zero in case of success and a negative error code in case of failure.
+ */
+int __init ubifs_compressors_init(void)
+{
+ int err;
+
+ err = compr_init(&lzo_compr);
+ if (err)
+ return err;
+
+ err = compr_init(&zlib_compr);
+ if (err)
+ goto out_lzo;
+
+ ubifs_compressors[UBIFS_COMPR_NONE] = &none_compr;
+ return 0;
+
+out_lzo:
+ compr_exit(&lzo_compr);
+ return err;
+}
+
+/**
+ * ubifs_compressors_exit - de-initialize UBIFS compressors.
+ */
+void __exit ubifs_compressors_exit(void)
+{
+ compr_exit(&lzo_compr);
+ compr_exit(&zlib_compr);
+}
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ * Adrian Hunter
+ */
+
+/*
+ * This file implements most of the debugging stuff which is compiled in only
+ * when it is enabled. But some debugging check functions are implemented in
+ * corresponding subsystem, just because they are closely related and utilize
+ * various local functions of those subsystems.
+ */
+
+#define UBIFS_DBG_PRESERVE_UBI
+
+#include "ubifs.h"
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+
+DEFINE_SPINLOCK(dbg_lock);
+
+static char dbg_key_buf0[128];
+static char dbg_key_buf1[128];
+
+unsigned int ubifs_msg_flags = UBIFS_MSG_FLAGS_DEFAULT;
+unsigned int ubifs_chk_flags = UBIFS_CHK_FLAGS_DEFAULT;
+unsigned int ubifs_tst_flags;
+
+module_param_named(debug_msgs, ubifs_msg_flags, uint, S_IRUGO | S_IWUSR);
+module_param_named(debug_chks, ubifs_chk_flags, uint, S_IRUGO | S_IWUSR);
+module_param_named(debug_tsts, ubifs_tst_flags, uint, S_IRUGO | S_IWUSR);
+
+MODULE_PARM_DESC(debug_msgs, "Debug message type flags");
+MODULE_PARM_DESC(debug_chks, "Debug check flags");
+MODULE_PARM_DESC(debug_tsts, "Debug special test flags");
+
+static const char *get_key_fmt(int fmt)
+{
+ switch (fmt) {
+ case UBIFS_SIMPLE_KEY_FMT:
+ return "simple";
+ default:
+ return "unknown/invalid format";
+ }
+}
+
+static const char *get_key_hash(int hash)
+{
+ switch (hash) {
+ case UBIFS_KEY_HASH_R5:
+ return "R5";
+ case UBIFS_KEY_HASH_TEST:
+ return "test";
+ default:
+ return "unknown/invalid name hash";
+ }
+}
+
+static const char *get_key_type(int type)
+{
+ switch (type) {
+ case UBIFS_INO_KEY:
+ return "inode";
+ case UBIFS_DENT_KEY:
+ return "direntry";
+ case UBIFS_XENT_KEY:
+ return "xentry";
+ case UBIFS_DATA_KEY:
+ return "data";
+ case UBIFS_TRUN_KEY:
+ return "truncate";
+ default:
+ return "unknown/invalid key";
+ }
+}
+
+static void sprintf_key(const struct ubifs_info *c, const union ubifs_key *key,
+ char *buffer)
+{
+ char *p = buffer;
+ int type = key_type(c, key);
+
+ if (c->key_fmt == UBIFS_SIMPLE_KEY_FMT) {
+ switch (type) {
+ case UBIFS_INO_KEY:
+ sprintf(p, "(%lu, %s)", key_inum(c, key),
+ get_key_type(type));
+ break;
+ case UBIFS_DENT_KEY:
+ case UBIFS_XENT_KEY:
+ sprintf(p, "(%lu, %s, %#08x)", key_inum(c, key),
+ get_key_type(type), key_hash(c, key));
+ break;
+ case UBIFS_DATA_KEY:
+ sprintf(p, "(%lu, %s, %u)", key_inum(c, key),
+ get_key_type(type), key_block(c, key));
+ break;
+ case UBIFS_TRUN_KEY:
+ sprintf(p, "(%lu, %s)",
+ key_inum(c, key), get_key_type(type));
+ break;
+ default:
+ sprintf(p, "(bad key type: %#08x, %#08x)",
+ key->u32[0], key->u32[1]);
+ }
+ } else
+ sprintf(p, "bad key format %d", c->key_fmt);
+}
+
+const char *dbg_key_str0(const struct ubifs_info *c, const union ubifs_key *key)
+{
+ /* dbg_lock must be held */
+ sprintf_key(c, key, dbg_key_buf0);
+ return dbg_key_buf0;
+}
+
+const char *dbg_key_str1(const struct ubifs_info *c, const union ubifs_key *key)
+{
+ /* dbg_lock must be held */
+ sprintf_key(c, key, dbg_key_buf1);
+ return dbg_key_buf1;
+}
+
+const char *dbg_ntype(int type)
+{
+ switch (type) {
+ case UBIFS_PAD_NODE:
+ return "padding node";
+ case UBIFS_SB_NODE:
+ return "superblock node";
+ case UBIFS_MST_NODE:
+ return "master node";
+ case UBIFS_REF_NODE:
+ return "reference node";
+ case UBIFS_INO_NODE:
+ return "inode node";
+ case UBIFS_DENT_NODE:
+ return "direntry node";
+ case UBIFS_XENT_NODE:
+ return "xentry node";
+ case UBIFS_DATA_NODE:
+ return "data node";
+ case UBIFS_TRUN_NODE:
+ return "truncate node";
+ case UBIFS_IDX_NODE:
+ return "indexing node";
+ case UBIFS_CS_NODE:
+ return "commit start node";
+ case UBIFS_ORPH_NODE:
+ return "orphan node";
+ default:
+ return "unknown node";
+ }
+}
+
+static const char *dbg_gtype(int type)
+{
+ switch (type) {
+ case UBIFS_NO_NODE_GROUP:
+ return "no node group";
+ case UBIFS_IN_NODE_GROUP:
+ return "in node group";
+ case UBIFS_LAST_OF_NODE_GROUP:
+ return "last of node group";
+ default:
+ return "unknown";
+ }
+}
+
+const char *dbg_cstate(int cmt_state)
+{
+ switch (cmt_state) {
+ case COMMIT_RESTING:
+ return "commit resting";
+ case COMMIT_BACKGROUND:
+ return "background commit requested";
+ case COMMIT_REQUIRED:
+ return "commit required";
+ case COMMIT_RUNNING_BACKGROUND:
+ return "BACKGROUND commit running";
+ case COMMIT_RUNNING_REQUIRED:
+ return "commit running and required";
+ case COMMIT_BROKEN:
+ return "broken commit";
+ default:
+ return "unknown commit state";
+ }
+}
+
+static void dump_ch(const struct ubifs_ch *ch)
+{
+ printk(KERN_DEBUG "\tmagic %#x\n", le32_to_cpu(ch->magic));
+ printk(KERN_DEBUG "\tcrc %#x\n", le32_to_cpu(ch->crc));
+ printk(KERN_DEBUG "\tnode_type %d (%s)\n", ch->node_type,
+ dbg_ntype(ch->node_type));
+ printk(KERN_DEBUG "\tgroup_type %d (%s)\n", ch->group_type,
+ dbg_gtype(ch->group_type));
+ printk(KERN_DEBUG "\tsqnum %llu\n",
+ (unsigned long long)le64_to_cpu(ch->sqnum));
+ printk(KERN_DEBUG "\tlen %u\n", le32_to_cpu(ch->len));
+}
+
+void dbg_dump_inode(const struct ubifs_info *c, const struct inode *inode)
+{
+ const struct ubifs_inode *ui = ubifs_inode(inode);
+
+ printk(KERN_DEBUG "inode %lu\n", inode->i_ino);
+ printk(KERN_DEBUG "size %llu\n",
+ (unsigned long long)i_size_read(inode));
+ printk(KERN_DEBUG "nlink %u\n", inode->i_nlink);
+ printk(KERN_DEBUG "uid %u\n", (unsigned int)inode->i_uid);
+ printk(KERN_DEBUG "gid %u\n", (unsigned int)inode->i_gid);
+ printk(KERN_DEBUG "atime %u.%u\n",
+ (unsigned int)inode->i_atime.tv_sec,
+ (unsigned int)inode->i_atime.tv_nsec);
+ printk(KERN_DEBUG "mtime %u.%u\n",
+ (unsigned int)inode->i_mtime.tv_sec,
+ (unsigned int)inode->i_mtime.tv_nsec);
+ printk(KERN_DEBUG "ctime %u.%u\n",
+ (unsigned int)inode->i_ctime.tv_sec,
+ (unsigned int)inode->i_ctime.tv_nsec);
+ printk(KERN_DEBUG "creat_sqnum %llu\n", ui->creat_sqnum);
+ printk(KERN_DEBUG "xattr_size %u\n", ui->xattr_size);
+ printk(KERN_DEBUG "xattr_cnt %u\n", ui->xattr_cnt);
+ printk(KERN_DEBUG "xattr_names %u\n", ui->xattr_names);
+ printk(KERN_DEBUG "dirty %u\n", ui->dirty);
+ printk(KERN_DEBUG "xattr %u\n", ui->xattr);
+ printk(KERN_DEBUG "flags %d\n", ui->flags);
+ printk(KERN_DEBUG "compr_type %d\n", ui->compr_type);
+ printk(KERN_DEBUG "data_len %d\n", ui->data_len);
+}
+
+void dbg_dump_node(const struct ubifs_info *c, const void *node)
+{
+ int i, n;
+ union ubifs_key key;
+ const struct ubifs_ch *ch = node;
+
+ if (dbg_failure_mode)
+ return;
+
+ /* If the magic is incorrect, just hexdump the first bytes */
+ if (le32_to_cpu(ch->magic) != UBIFS_NODE_MAGIC) {
+ printk(KERN_DEBUG "Not a node, first %zu bytes:", UBIFS_CH_SZ);
+ print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1,
+ (void *)node, UBIFS_CH_SZ, 1);
+ return;
+ }
+
+ spin_lock(&dbg_lock);
+ dump_ch(node);
+
+ switch (ch->node_type) {
+ case UBIFS_PAD_NODE:
+ {
+ const struct ubifs_pad_node *pad = node;
+
+ printk(KERN_DEBUG "\tpad_len %u\n",
+ le32_to_cpu(pad->pad_len));
+ break;
+ }
+ case UBIFS_SB_NODE:
+ {
+ const struct ubifs_sb_node *sup = node;
+ unsigned int sup_flags = le32_to_cpu(sup->flags);
+
+ printk(KERN_DEBUG "\tkey_hash %d (%s)\n",
+ (int)sup->key_hash, get_key_hash(sup->key_hash));
+ printk(KERN_DEBUG "\tkey_fmt %d (%s)\n",
+ (int)sup->key_fmt, get_key_fmt(sup->key_fmt));
+ printk(KERN_DEBUG "\tflags %#x\n", sup_flags);
+ printk(KERN_DEBUG "\t big_lpt %u\n",
+ !!(sup_flags & UBIFS_FLG_BIGLPT));
+ printk(KERN_DEBUG "\tmin_io_size %u\n",
+ le32_to_cpu(sup->min_io_size));
+ printk(KERN_DEBUG "\tleb_size %u\n",
+ le32_to_cpu(sup->leb_size));
+ printk(KERN_DEBUG "\tleb_cnt %u\n",
+ le32_to_cpu(sup->leb_cnt));
+ printk(KERN_DEBUG "\tmax_leb_cnt %u\n",
+ le32_to_cpu(sup->max_leb_cnt));
+ printk(KERN_DEBUG "\tmax_bud_bytes %llu\n",
+ (unsigned long long)le64_to_cpu(sup->max_bud_bytes));
+ printk(KERN_DEBUG "\tlog_lebs %u\n",
+ le32_to_cpu(sup->log_lebs));
+ printk(KERN_DEBUG "\tlpt_lebs %u\n",
+ le32_to_cpu(sup->lpt_lebs));
+ printk(KERN_DEBUG "\torph_lebs %u\n",
+ le32_to_cpu(sup->orph_lebs));
+ printk(KERN_DEBUG "\tjhead_cnt %u\n",
+ le32_to_cpu(sup->jhead_cnt));
+ printk(KERN_DEBUG "\tfanout %u\n",
+ le32_to_cpu(sup->fanout));
+ printk(KERN_DEBUG "\tlsave_cnt %u\n",
+ le32_to_cpu(sup->lsave_cnt));
+ printk(KERN_DEBUG "\tdefault_compr %u\n",
+ (int)le16_to_cpu(sup->default_compr));
+ printk(KERN_DEBUG "\trp_size %llu\n",
+ (unsigned long long)le64_to_cpu(sup->rp_size));
+ printk(KERN_DEBUG "\trp_uid %u\n",
+ le32_to_cpu(sup->rp_uid));
+ printk(KERN_DEBUG "\trp_gid %u\n",
+ le32_to_cpu(sup->rp_gid));
+ printk(KERN_DEBUG "\tfmt_version %u\n",
+ le32_to_cpu(sup->fmt_version));
+ printk(KERN_DEBUG "\ttime_gran %u\n",
+ le32_to_cpu(sup->time_gran));
+ printk(KERN_DEBUG "\tUUID %02X%02X%02X%02X-%02X%02X"
+ "-%02X%02X-%02X%02X-%02X%02X%02X%02X%02X%02X\n",
+ sup->uuid[0], sup->uuid[1], sup->uuid[2], sup->uuid[3],
+ sup->uuid[4], sup->uuid[5], sup->uuid[6], sup->uuid[7],
+ sup->uuid[8], sup->uuid[9], sup->uuid[10], sup->uuid[11],
+ sup->uuid[12], sup->uuid[13], sup->uuid[14],
+ sup->uuid[15]);
+ break;
+ }
+ case UBIFS_MST_NODE:
+ {
+ const struct ubifs_mst_node *mst = node;
+
+ printk(KERN_DEBUG "\thighest_inum %llu\n",
+ (unsigned long long)le64_to_cpu(mst->highest_inum));
+ printk(KERN_DEBUG "\tcommit number %llu\n",
+ (unsigned long long)le64_to_cpu(mst->cmt_no));
+ printk(KERN_DEBUG "\tflags %#x\n",
+ le32_to_cpu(mst->flags));
+ printk(KERN_DEBUG "\tlog_lnum %u\n",
+ le32_to_cpu(mst->log_lnum));
+ printk(KERN_DEBUG "\troot_lnum %u\n",
+ le32_to_cpu(mst->root_lnum));
+ printk(KERN_DEBUG "\troot_offs %u\n",
+ le32_to_cpu(mst->root_offs));
+ printk(KERN_DEBUG "\troot_len %u\n",
+ le32_to_cpu(mst->root_len));
+ printk(KERN_DEBUG "\tgc_lnum %u\n",
+ le32_to_cpu(mst->gc_lnum));
+ printk(KERN_DEBUG "\tihead_lnum %u\n",
+ le32_to_cpu(mst->ihead_lnum));
+ printk(KERN_DEBUG "\tihead_offs %u\n",
+ le32_to_cpu(mst->ihead_offs));
+ printk(KERN_DEBUG "\tindex_size %u\n",
+ le32_to_cpu(mst->index_size));
+ printk(KERN_DEBUG "\tlpt_lnum %u\n",
+ le32_to_cpu(mst->lpt_lnum));
+ printk(KERN_DEBUG "\tlpt_offs %u\n",
+ le32_to_cpu(mst->lpt_offs));
+ printk(KERN_DEBUG "\tnhead_lnum %u\n",
+ le32_to_cpu(mst->nhead_lnum));
+ printk(KERN_DEBUG "\tnhead_offs %u\n",
+ le32_to_cpu(mst->nhead_offs));
+ printk(KERN_DEBUG "\tltab_lnum %u\n",
+ le32_to_cpu(mst->ltab_lnum));
+ printk(KERN_DEBUG "\tltab_offs %u\n",
+ le32_to_cpu(mst->ltab_offs));
+ printk(KERN_DEBUG "\tlsave_lnum %u\n",
+ le32_to_cpu(mst->lsave_lnum));
+ printk(KERN_DEBUG "\tlsave_offs %u\n",
+ le32_to_cpu(mst->lsave_offs));
+ printk(KERN_DEBUG "\tlscan_lnum %u\n",
+ le32_to_cpu(mst->lscan_lnum));
+ printk(KERN_DEBUG "\tleb_cnt %u\n",
+ le32_to_cpu(mst->leb_cnt));
+ printk(KERN_DEBUG "\tempty_lebs %u\n",
+ le32_to_cpu(mst->empty_lebs));
+ printk(KERN_DEBUG "\tidx_lebs %u\n",
+ le32_to_cpu(mst->idx_lebs));
+ printk(KERN_DEBUG "\ttotal_free %llu\n",
+ (unsigned long long)le64_to_cpu(mst->total_free));
+ printk(KERN_DEBUG "\ttotal_dirty %llu\n",
+ (unsigned long long)le64_to_cpu(mst->total_dirty));
+ printk(KERN_DEBUG "\ttotal_used %llu\n",
+ (unsigned long long)le64_to_cpu(mst->total_used));
+ printk(KERN_DEBUG "\ttotal_dead %llu\n",
+ (unsigned long long)le64_to_cpu(mst->total_dead));
+ printk(KERN_DEBUG "\ttotal_dark %llu\n",
+ (unsigned long long)le64_to_cpu(mst->total_dark));
+ break;
+ }
+ case UBIFS_REF_NODE:
+ {
+ const struct ubifs_ref_node *ref = node;
+
+ printk(KERN_DEBUG "\tlnum %u\n",
+ le32_to_cpu(ref->lnum));
+ printk(KERN_DEBUG "\toffs %u\n",
+ le32_to_cpu(ref->offs));
+ printk(KERN_DEBUG "\tjhead %u\n",
+ le32_to_cpu(ref->jhead));
+ break;
+ }
+ case UBIFS_INO_NODE:
+ {
+ const struct ubifs_ino_node *ino = node;
+
+ key_read(c, &ino->key, &key);
+ printk(KERN_DEBUG "\tkey %s\n", DBGKEY(&key));
+ printk(KERN_DEBUG "\tcreat_sqnum %llu\n",
+ (unsigned long long)le64_to_cpu(ino->creat_sqnum));
+ printk(KERN_DEBUG "\tsize %llu\n",
+ (unsigned long long)le64_to_cpu(ino->size));
+ printk(KERN_DEBUG "\tnlink %u\n",
+ le32_to_cpu(ino->nlink));
+ printk(KERN_DEBUG "\tatime %lld.%u\n",
+ (long long)le64_to_cpu(ino->atime_sec),
+ le32_to_cpu(ino->atime_nsec));
+ printk(KERN_DEBUG "\tmtime %lld.%u\n",
+ (long long)le64_to_cpu(ino->mtime_sec),
+ le32_to_cpu(ino->mtime_nsec));
+ printk(KERN_DEBUG "\tctime %lld.%u\n",
+ (long long)le64_to_cpu(ino->ctime_sec),
+ le32_to_cpu(ino->ctime_nsec));
+ printk(KERN_DEBUG "\tuid %u\n",
+ le32_to_cpu(ino->uid));
+ printk(KERN_DEBUG "\tgid %u\n",
+ le32_to_cpu(ino->gid));
+ printk(KERN_DEBUG "\tmode %u\n",
+ le32_to_cpu(ino->mode));
+ printk(KERN_DEBUG "\tflags %#x\n",
+ le32_to_cpu(ino->flags));
+ printk(KERN_DEBUG "\txattr_cnt %u\n",
+ le32_to_cpu(ino->xattr_cnt));
+ printk(KERN_DEBUG "\txattr_size %u\n",
+ le32_to_cpu(ino->xattr_size));
+ printk(KERN_DEBUG "\txattr_names %u\n",
+ le32_to_cpu(ino->xattr_names));
+ printk(KERN_DEBUG "\tcompr_type %#x\n",
+ (int)le16_to_cpu(ino->compr_type));
+ printk(KERN_DEBUG "\tdata len %u\n",
+ le32_to_cpu(ino->data_len));
+ break;
+ }
+ case UBIFS_DENT_NODE:
+ case UBIFS_XENT_NODE:
+ {
+ const struct ubifs_dent_node *dent = node;
+ int nlen = le16_to_cpu(dent->nlen);
+
+ key_read(c, &dent->key, &key);
+ printk(KERN_DEBUG "\tkey %s\n", DBGKEY(&key));
+ printk(KERN_DEBUG "\tinum %llu\n",
+ (unsigned long long)le64_to_cpu(dent->inum));
+ printk(KERN_DEBUG "\ttype %d\n", (int)dent->type);
+ printk(KERN_DEBUG "\tnlen %d\n", nlen);
+ printk(KERN_DEBUG "\tname ");
+
+ if (nlen > UBIFS_MAX_NLEN)
+ printk(KERN_DEBUG "(bad name length, not printing, "
+ "bad or corrupted node)");
+ else {
+ for (i = 0; i < nlen && dent->name[i]; i++)
+ printk("%c", dent->name[i]);
+ }
+ printk("\n");
+
+ break;
+ }
+ case UBIFS_DATA_NODE:
+ {
+ const struct ubifs_data_node *dn = node;
+ int dlen = le32_to_cpu(ch->len) - UBIFS_DATA_NODE_SZ;
+
+ key_read(c, &dn->key, &key);
+ printk(KERN_DEBUG "\tkey %s\n", DBGKEY(&key));
+ printk(KERN_DEBUG "\tsize %u\n",
+ le32_to_cpu(dn->size));
+ printk(KERN_DEBUG "\tcompr_typ %d\n",
+ (int)le16_to_cpu(dn->compr_type));
+ printk(KERN_DEBUG "\tdata size %d\n",
+ dlen);
+ printk(KERN_DEBUG "\tdata:\n");
+ print_hex_dump(KERN_DEBUG, "\t", DUMP_PREFIX_OFFSET, 32, 1,
+ (void *)&dn->data, dlen, 0);
+ break;
+ }
+ case UBIFS_TRUN_NODE:
+ {
+ const struct ubifs_trun_node *trun = node;
+
+ printk(KERN_DEBUG "\tinum %u\n",
+ le32_to_cpu(trun->inum));
+ printk(KERN_DEBUG "\told_size %llu\n",
+ (unsigned long long)le64_to_cpu(trun->old_size));
+ printk(KERN_DEBUG "\tnew_size %llu\n",
+ (unsigned long long)le64_to_cpu(trun->new_size));
+ break;
+ }
+ case UBIFS_IDX_NODE:
+ {
+ const struct ubifs_idx_node *idx = node;
+
+ n = le16_to_cpu(idx->child_cnt);
+ printk(KERN_DEBUG "\tchild_cnt %d\n", n);
+ printk(KERN_DEBUG "\tlevel %d\n",
+ (int)le16_to_cpu(idx->level));
+ printk(KERN_DEBUG "\tBranches:\n");
+
+ for (i = 0; i < n && i < c->fanout - 1; i++) {
+ const struct ubifs_branch *br;
+
+ br = ubifs_idx_branch(c, idx, i);
+ key_read(c, &br->key, &key);
+ printk(KERN_DEBUG "\t%d: LEB %d:%d len %d key %s\n",
+ i, le32_to_cpu(br->lnum), le32_to_cpu(br->offs),
+ le32_to_cpu(br->len), DBGKEY(&key));
+ }
+ break;
+ }
+ case UBIFS_CS_NODE:
+ break;
+ case UBIFS_ORPH_NODE:
+ {
+ const struct ubifs_orph_node *orph = node;
+
+ printk(KERN_DEBUG "\tcommit number %llu\n",
+ (unsigned long long)
+ le64_to_cpu(orph->cmt_no) & LLONG_MAX);
+ printk(KERN_DEBUG "\tlast node flag %llu\n",
+ (unsigned long long)(le64_to_cpu(orph->cmt_no)) >> 63);
+ n = (le32_to_cpu(ch->len) - UBIFS_ORPH_NODE_SZ) >> 3;
+ printk(KERN_DEBUG "\t%d orphan inode numbers:\n", n);
+ for (i = 0; i < n; i++)
+ printk(KERN_DEBUG "\t ino %llu\n",
+ le64_to_cpu(orph->inos[i]));
+ break;
+ }
+ default:
+ printk(KERN_DEBUG "node type %d was not recognized\n",
+ (int)ch->node_type);
+ }
+ spin_unlock(&dbg_lock);
+}
+
+void dbg_dump_budget_req(const struct ubifs_budget_req *req)
+{
+ spin_lock(&dbg_lock);
+ printk(KERN_DEBUG "Budgeting request: new_ino %d, dirtied_ino %d\n",
+ req->new_ino, req->dirtied_ino);
+ printk(KERN_DEBUG "\tnew_ino_d %d, dirtied_ino_d %d\n",
+ req->new_ino_d, req->dirtied_ino_d);
+ printk(KERN_DEBUG "\tnew_page %d, dirtied_page %d\n",
+ req->new_page, req->dirtied_page);
+ printk(KERN_DEBUG "\tnew_dent %d, mod_dent %d\n",
+ req->new_dent, req->mod_dent);
+ printk(KERN_DEBUG "\tidx_growth %d\n", req->idx_growth);
+ printk(KERN_DEBUG "\tdata_growth %d dd_growth %d\n",
+ req->data_growth, req->dd_growth);
+ spin_unlock(&dbg_lock);
+}
+
+void dbg_dump_lstats(const struct ubifs_lp_stats *lst)
+{
+ spin_lock(&dbg_lock);
+ printk(KERN_DEBUG "Lprops statistics: empty_lebs %d, idx_lebs %d\n",
+ lst->empty_lebs, lst->idx_lebs);
+ printk(KERN_DEBUG "\ttaken_empty_lebs %d, total_free %lld, "
+ "total_dirty %lld\n", lst->taken_empty_lebs, lst->total_free,
+ lst->total_dirty);
+ printk(KERN_DEBUG "\ttotal_used %lld, total_dark %lld, "
+ "total_dead %lld\n", lst->total_used, lst->total_dark,
+ lst->total_dead);
+ spin_unlock(&dbg_lock);
+}
+
+void dbg_dump_budg(struct ubifs_info *c)
+{
+ int i;
+ struct rb_node *rb;
+ struct ubifs_bud *bud;
+ struct ubifs_gced_idx_leb *idx_gc;
+
+ spin_lock(&dbg_lock);
+ printk(KERN_DEBUG "Budgeting info: budg_data_growth %lld, "
+ "budg_dd_growth %lld, budg_idx_growth %lld\n",
+ c->budg_data_growth, c->budg_dd_growth, c->budg_idx_growth);
+ printk(KERN_DEBUG "\tdata budget sum %lld, total budget sum %lld, "
+ "freeable_cnt %d\n", c->budg_data_growth + c->budg_dd_growth,
+ c->budg_data_growth + c->budg_dd_growth + c->budg_idx_growth,
+ c->freeable_cnt);
+ printk(KERN_DEBUG "\tmin_idx_lebs %d, old_idx_sz %lld, "
+ "calc_idx_sz %lld, idx_gc_cnt %d\n", c->min_idx_lebs,
+ c->old_idx_sz, c->calc_idx_sz, c->idx_gc_cnt);
+ printk(KERN_DEBUG "\tdirty_pg_cnt %ld, dirty_zn_cnt %ld, "
+ "clean_zn_cnt %ld\n", atomic_long_read(&c->dirty_pg_cnt),
+ atomic_long_read(&c->dirty_zn_cnt),
+ atomic_long_read(&c->clean_zn_cnt));
+ printk(KERN_DEBUG "\tdark_wm %d, dead_wm %d, max_idx_node_sz %d\n",
+ c->dark_wm, c->dead_wm, c->max_idx_node_sz);
+ printk(KERN_DEBUG "\tgc_lnum %d, ihead_lnum %d\n",
+ c->gc_lnum, c->ihead_lnum);
+ for (i = 0; i < c->jhead_cnt; i++)
+ printk(KERN_DEBUG "\tjhead %d\t LEB %d\n",
+ c->jheads[i].wbuf.jhead, c->jheads[i].wbuf.lnum);
+ for (rb = rb_first(&c->buds); rb; rb = rb_next(rb)) {
+ bud = rb_entry(rb, struct ubifs_bud, rb);
+ printk(KERN_DEBUG "\tbud LEB %d\n", bud->lnum);
+ }
+ list_for_each_entry(bud, &c->old_buds, list)
+ printk(KERN_DEBUG "\told bud LEB %d\n", bud->lnum);
+ list_for_each_entry(idx_gc, &c->idx_gc, list)
+ printk(KERN_DEBUG "\tGC'ed idx LEB %d unmap %d\n",
+ idx_gc->lnum, idx_gc->unmap);
+ printk(KERN_DEBUG "\tcommit state %d\n", c->cmt_state);
+ spin_unlock(&dbg_lock);
+}
+
+void dbg_dump_lprop(const struct ubifs_info *c, const struct ubifs_lprops *lp)
+{
+ printk(KERN_DEBUG "LEB %d lprops: free %d, dirty %d (used %d), "
+ "flags %#x\n", lp->lnum, lp->free, lp->dirty,
+ c->leb_size - lp->free - lp->dirty, lp->flags);
+}
+
+void dbg_dump_lprops(struct ubifs_info *c)
+{
+ int lnum, err;
+ struct ubifs_lprops lp;
+ struct ubifs_lp_stats lst;
+
+ printk(KERN_DEBUG "Dumping LEB properties\n");
+ ubifs_get_lp_stats(c, &lst);
+ dbg_dump_lstats(&lst);
+
+ for (lnum = c->main_first; lnum < c->leb_cnt; lnum++) {
+ err = ubifs_read_one_lp(c, lnum, &lp);
+ if (err)
+ ubifs_err("cannot read lprops for LEB %d", lnum);
+
+ dbg_dump_lprop(c, &lp);
+ }
+}
+
+void dbg_dump_leb(const struct ubifs_info *c, int lnum)
+{
+ struct ubifs_scan_leb *sleb;
+ struct ubifs_scan_node *snod;
+
+ if (dbg_failure_mode)
+ return;
+
+ printk(KERN_DEBUG "Dumping LEB %d\n", lnum);
+
+ sleb = ubifs_scan(c, lnum, 0, c->dbg_buf);
+ if (IS_ERR(sleb)) {
+ ubifs_err("scan error %d", (int)PTR_ERR(sleb));
+ return;
+ }
+
+ printk(KERN_DEBUG "LEB %d has %d nodes ending at %d\n", lnum,
+ sleb->nodes_cnt, sleb->endpt);
+
+ list_for_each_entry(snod, &sleb->nodes, list) {
+ cond_resched();
+ printk(KERN_DEBUG "Dumping node at LEB %d:%d len %d\n", lnum,
+ snod->offs, snod->len);
+ dbg_dump_node(c, snod->node);
+ }
+
+ ubifs_scan_destroy(sleb);
+ return;
+}
+
+void dbg_dump_znode(const struct ubifs_info *c,
+ const struct ubifs_znode *znode)
+{
+ int n;
+ const struct ubifs_zbranch *zbr;
+
+ spin_lock(&dbg_lock);
+ if (znode->parent)
+ zbr = &znode->parent->zbranch[znode->iip];
+ else
+ zbr = &c->zroot;
+
+ printk(KERN_DEBUG "znode %p, LEB %d:%d len %d parent %p iip %d level %d"
+ " child_cnt %d flags %lx\n", znode, zbr->lnum, zbr->offs,
+ zbr->len, znode->parent, znode->iip, znode->level,
+ znode->child_cnt, znode->flags);
+
+ if (znode->child_cnt <= 0 || znode->child_cnt > c->fanout) {
+ spin_unlock(&dbg_lock);
+ return;
+ }
+
+ printk(KERN_DEBUG "zbranches:\n");
+ for (n = 0; n < znode->child_cnt; n++) {
+ zbr = &znode->zbranch[n];
+ if (znode->level > 0)
+ printk(KERN_DEBUG "\t%d: znode %p LEB %d:%d len %d key "
+ "%s\n", n, zbr->znode, zbr->lnum,
+ zbr->offs, zbr->len,
+ DBGKEY(&zbr->key));
+ else
+ printk(KERN_DEBUG "\t%d: LNC %p LEB %d:%d len %d key "
+ "%s\n", n, zbr->znode, zbr->lnum,
+ zbr->offs, zbr->len,
+ DBGKEY(&zbr->key));
+ }
+ spin_unlock(&dbg_lock);
+}
+
+void dbg_dump_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat)
+{
+ int i;
+
+ printk(KERN_DEBUG "Dumping heap cat %d (%d elements)\n",
+ cat, heap->cnt);
+ for (i = 0; i < heap->cnt; i++) {
+ struct ubifs_lprops *lprops = heap->arr[i];
+
+ printk(KERN_DEBUG "\t%d. LEB %d hpos %d free %d dirty %d "
+ "flags %d\n", i, lprops->lnum, lprops->hpos,
+ lprops->free, lprops->dirty, lprops->flags);
+ }
+}
+
+void dbg_dump_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
+ struct ubifs_nnode *parent, int iip)
+{
+ int i;
+
+ printk(KERN_DEBUG "Dumping pnode:\n");
+ printk(KERN_DEBUG "\taddress %zx parent %zx cnext %zx\n",
+ (size_t)pnode, (size_t)parent, (size_t)pnode->cnext);
+ printk(KERN_DEBUG "\tflags %lu iip %d level %d num %d\n",
+ pnode->flags, iip, pnode->level, pnode->num);
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ struct ubifs_lprops *lp = &pnode->lprops[i];
+
+ printk(KERN_DEBUG "\t%d: free %d dirty %d flags %d lnum %d\n",
+ i, lp->free, lp->dirty, lp->flags, lp->lnum);
+ }
+}
+
+void dbg_dump_tnc(struct ubifs_info *c)
+{
+ struct ubifs_znode *znode;
+ int level;
+
+ printk(KERN_DEBUG "\n");
+ printk(KERN_DEBUG "Dumping the TNC tree\n");
+ znode = ubifs_tnc_levelorder_next(c->zroot.znode, NULL);
+ level = znode->level;
+ printk(KERN_DEBUG "== Level %d ==\n", level);
+ while (znode) {
+ if (level != znode->level) {
+ level = znode->level;
+ printk(KERN_DEBUG "== Level %d ==\n", level);
+ }
+ dbg_dump_znode(c, znode);
+ znode = ubifs_tnc_levelorder_next(c->zroot.znode, znode);
+ }
+
+ printk(KERN_DEBUG "\n");
+}
+
+static int dump_znode(struct ubifs_info *c, struct ubifs_znode *znode,
+ void *priv)
+{
+ dbg_dump_znode(c, znode);
+ return 0;
+}
+
+/**
+ * dbg_dump_index - dump the on-flash index.
+ * @c: UBIFS file-system description object
+ *
+ * This function dumps whole UBIFS indexing B-tree, unlike 'dbg_dump_tnc()'
+ * which dumps only in-memory znodes and does not read znodes which from flash.
+ */
+void dbg_dump_index(struct ubifs_info *c)
+{
+ dbg_walk_index(c, NULL, dump_znode, NULL);
+}
+
+/**
+ * dbg_check_synced_i_size - check synchronized inode size.
+ * @inode: inode to check
+ *
+ * If inode is clean, synchronized inode size has to be equivalent to current
+ * inode size. This function has to be called only for locked inodes (@i_mutex
+ * has to be locked). Returns %0 if synchronized inode size if correct, and
+ * %-EINVAL if not.
+ */
+int dbg_check_synced_i_size(struct inode *inode)
+{
+ int err = 0;
+ struct ubifs_inode *ui = ubifs_inode(inode);
+
+ if (!(ubifs_chk_flags & UBIFS_CHK_GEN))
+ return 0;
+ if (!S_ISREG(inode->i_mode))
+ return 0;
+
+ mutex_lock(&ui->ui_mutex);
+ spin_lock(&ui->ui_lock);
+ if (ui->ui_size != ui->synced_i_size && !ui->dirty) {
+ ubifs_err("ui_size is %lld, synced_i_size is %lld, but inode "
+ "is clean", ui->ui_size, ui->synced_i_size);
+ ubifs_err("i_ino %lu, i_mode %#x, i_size %lld", inode->i_ino,
+ inode->i_mode, i_size_read(inode));
+ dbg_dump_stack();
+ err = -EINVAL;
+ }
+ spin_unlock(&ui->ui_lock);
+ mutex_unlock(&ui->ui_mutex);
+ return err;
+}
+
+/*
+ * dbg_check_dir - check directory inode size and link count.
+ * @c: UBIFS file-system description object
+ * @dir: the directory to calculate size for
+ * @size: the result is returned here
+ *
+ * This function makes sure that directory size and link count are correct.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ *
+ * Note, it is good idea to make sure the @dir->i_mutex is locked before
+ * calling this function.
+ */
+int dbg_check_dir_size(struct ubifs_info *c, const struct inode *dir)
+{
+ unsigned int nlink = 2;
+ union ubifs_key key;
+ struct ubifs_dent_node *dent, *pdent = NULL;
+ struct qstr nm = { .name = NULL };
+ loff_t size = UBIFS_INO_NODE_SZ;
+
+ if (!(ubifs_chk_flags & UBIFS_CHK_GEN))
+ return 0;
+
+ if (!S_ISDIR(dir->i_mode))
+ return 0;
+
+ lowest_dent_key(c, &key, dir->i_ino);
+ while (1) {
+ int err;
+
+ dent = ubifs_tnc_next_ent(c, &key, &nm);
+ if (IS_ERR(dent)) {
+ err = PTR_ERR(dent);
+ if (err == -ENOENT)
+ break;
+ return err;
+ }
+
+ nm.name = dent->name;
+ nm.len = le16_to_cpu(dent->nlen);
+ size += CALC_DENT_SIZE(nm.len);
+ if (dent->type == UBIFS_ITYPE_DIR)
+ nlink += 1;
+ kfree(pdent);
+ pdent = dent;
+ key_read(c, &dent->key, &key);
+ }
+ kfree(pdent);
+
+ if (i_size_read(dir) != size) {
+ ubifs_err("directory inode %lu has size %llu, "
+ "but calculated size is %llu", dir->i_ino,
+ (unsigned long long)i_size_read(dir),
+ (unsigned long long)size);
+ dump_stack();
+ return -EINVAL;
+ }
+ if (dir->i_nlink != nlink) {
+ ubifs_err("directory inode %lu has nlink %u, but calculated "
+ "nlink is %u", dir->i_ino, dir->i_nlink, nlink);
+ dump_stack();
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/**
+ * dbg_check_key_order - make sure that colliding keys are properly ordered.
+ * @c: UBIFS file-system description object
+ * @zbr1: first zbranch
+ * @zbr2: following zbranch
+ *
+ * In UBIFS indexing B-tree colliding keys has to be sorted in binary order of
+ * names of the direntries/xentries which are referred by the keys. This
+ * function reads direntries/xentries referred by @zbr1 and @zbr2 and makes
+ * sure the name of direntry/xentry referred by @zbr1 is less than
+ * direntry/xentry referred by @zbr2. Returns zero if this is true, %1 if not,
+ * and a negative error code in case of failure.
+ */
+static int dbg_check_key_order(struct ubifs_info *c, struct ubifs_zbranch *zbr1,
+ struct ubifs_zbranch *zbr2)
+{
+ int err, nlen1, nlen2, cmp;
+ struct ubifs_dent_node *dent1, *dent2;
+ union ubifs_key key;
+
+ ubifs_assert(!keys_cmp(c, &zbr1->key, &zbr2->key));
+ dent1 = kmalloc(UBIFS_MAX_DENT_NODE_SZ, GFP_NOFS);
+ if (!dent1)
+ return -ENOMEM;
+ dent2 = kmalloc(UBIFS_MAX_DENT_NODE_SZ, GFP_NOFS);
+ if (!dent2) {
+ err = -ENOMEM;
+ goto out_free;
+ }
+
+ err = ubifs_tnc_read_node(c, zbr1, dent1);
+ if (err)
+ goto out_free;
+ err = ubifs_validate_entry(c, dent1);
+ if (err)
+ goto out_free;
+
+ err = ubifs_tnc_read_node(c, zbr2, dent2);
+ if (err)
+ goto out_free;
+ err = ubifs_validate_entry(c, dent2);
+ if (err)
+ goto out_free;
+
+ /* Make sure node keys are the same as in zbranch */
+ err = 1;
+ key_read(c, &dent1->key, &key);
+ if (keys_cmp(c, &zbr1->key, &key)) {
+ dbg_err("1st entry at %d:%d has key %s", zbr1->lnum,
+ zbr1->offs, DBGKEY(&key));
+ dbg_err("but it should have key %s according to tnc",
+ DBGKEY(&zbr1->key));
+ dbg_dump_node(c, dent1);
+ goto out_free;
+ }
+
+ key_read(c, &dent2->key, &key);
+ if (keys_cmp(c, &zbr2->key, &key)) {
+ dbg_err("2nd entry at %d:%d has key %s", zbr1->lnum,
+ zbr1->offs, DBGKEY(&key));
+ dbg_err("but it should have key %s according to tnc",
+ DBGKEY(&zbr2->key));
+ dbg_dump_node(c, dent2);
+ goto out_free;
+ }
+
+ nlen1 = le16_to_cpu(dent1->nlen);
+ nlen2 = le16_to_cpu(dent2->nlen);
+
+ cmp = memcmp(dent1->name, dent2->name, min_t(int, nlen1, nlen2));
+ if (cmp < 0 || (cmp == 0 && nlen1 < nlen2)) {
+ err = 0;
+ goto out_free;
+ }
+ if (cmp == 0 && nlen1 == nlen2)
+ dbg_err("2 xent/dent nodes with the same name");
+ else
+ dbg_err("bad order of colliding key %s",
+ DBGKEY(&key));
+
+ dbg_msg("first node at %d:%d\n", zbr1->lnum, zbr1->offs);
+ dbg_dump_node(c, dent1);
+ dbg_msg("second node at %d:%d\n", zbr2->lnum, zbr2->offs);
+ dbg_dump_node(c, dent2);
+
+out_free:
+ kfree(dent2);
+ kfree(dent1);
+ return err;
+}
+
+/**
+ * dbg_check_znode - check if znode is all right.
+ * @c: UBIFS file-system description object
+ * @zbr: zbranch which points to this znode
+ *
+ * This function makes sure that znode referred to by @zbr is all right.
+ * Returns zero if it is, and %-EINVAL if it is not.
+ */
+static int dbg_check_znode(struct ubifs_info *c, struct ubifs_zbranch *zbr)
+{
+ struct ubifs_znode *znode = zbr->znode;
+ struct ubifs_znode *zp = znode->parent;
+ int n, err, cmp;
+
+ if (znode->child_cnt <= 0 || znode->child_cnt > c->fanout) {
+ err = 1;
+ goto out;
+ }
+ if (znode->level < 0) {
+ err = 2;
+ goto out;
+ }
+ if (znode->iip < 0 || znode->iip >= c->fanout) {
+ err = 3;
+ goto out;
+ }
+
+ if (zbr->len == 0)
+ /* Only dirty zbranch may have no on-flash nodes */
+ if (!ubifs_zn_dirty(znode)) {
+ err = 4;
+ goto out;
+ }
+
+ if (ubifs_zn_dirty(znode)) {
+ /*
+ * If znode is dirty, its parent has to be dirty as well. The
+ * order of the operation is important, so we have to have
+ * memory barriers.
+ */
+ smp_mb();
+ if (zp && !ubifs_zn_dirty(zp)) {
+ /*
+ * The dirty flag is atomic and is cleared outside the
+ * TNC mutex, so znode's dirty flag may now have
+ * been cleared. The child is always cleared before the
+ * parent, so we just need to check again.
+ */
+ smp_mb();
+ if (ubifs_zn_dirty(znode)) {
+ err = 5;
+ goto out;
+ }
+ }
+ }
+
+ if (zp) {
+ const union ubifs_key *min, *max;
+
+ if (znode->level != zp->level - 1) {
+ err = 6;
+ goto out;
+ }
+
+ /* Make sure the 'parent' pointer in our znode is correct */
+ err = ubifs_search_zbranch(c, zp, &zbr->key, &n);
+ if (!err) {
+ /* This zbranch does not exist in the parent */
+ err = 7;
+ goto out;
+ }
+
+ if (znode->iip >= zp->child_cnt) {
+ err = 8;
+ goto out;
+ }
+
+ if (znode->iip != n) {
+ /* This may happen only in case of collisions */
+ if (keys_cmp(c, &zp->zbranch[n].key,
+ &zp->zbranch[znode->iip].key)) {
+ err = 9;
+ goto out;
+ }
+ n = znode->iip;
+ }
+
+ /*
+ * Make sure that the first key in our znode is greater than or
+ * equal to the key in the pointing zbranch.
+ */
+ min = &zbr->key;
+ cmp = keys_cmp(c, min, &znode->zbranch[0].key);
+ if (cmp == 1) {
+ err = 10;
+ goto out;
+ }
+
+ if (n + 1 < zp->child_cnt) {
+ max = &zp->zbranch[n + 1].key;
+
+ /*
+ * Make sure the last key in our znode is less or
+ * equivalent than the the key in zbranch which goes
+ * after our pointing zbranch.
+ */
+ cmp = keys_cmp(c, max,
+ &znode->zbranch[znode->child_cnt - 1].key);
+ if (cmp == -1) {
+ err = 11;
+ goto out;
+ }
+ }
+ } else {
+ /* This may only be root znode */
+ if (zbr != &c->zroot) {
+ err = 12;
+ goto out;
+ }
+ }
+
+ /*
+ * Make sure that next key is greater or equivalent then the previous
+ * one.
+ */
+ for (n = 1; n < znode->child_cnt; n++) {
+ cmp = keys_cmp(c, &znode->zbranch[n - 1].key,
+ &znode->zbranch[n].key);
+ if (cmp > 0) {
+ err = 13;
+ goto out;
+ }
+ if (cmp == 0) {
+ /* This can only be keys with colliding hash */
+ if (!is_hash_key(c, &znode->zbranch[n].key)) {
+ err = 14;
+ goto out;
+ }
+
+ if (znode->level != 0 || c->replaying)
+ continue;
+
+ /*
+ * Colliding keys should follow binary order of
+ * corresponding xentry/dentry names.
+ */
+ err = dbg_check_key_order(c, &znode->zbranch[n - 1],
+ &znode->zbranch[n]);
+ if (err < 0)
+ return err;
+ if (err) {
+ err = 15;
+ goto out;
+ }
+ }
+ }
+
+ for (n = 0; n < znode->child_cnt; n++) {
+ if (!znode->zbranch[n].znode &&
+ (znode->zbranch[n].lnum == 0 ||
+ znode->zbranch[n].len == 0)) {
+ err = 16;
+ goto out;
+ }
+
+ if (znode->zbranch[n].lnum != 0 &&
+ znode->zbranch[n].len == 0) {
+ err = 17;
+ goto out;
+ }
+
+ if (znode->zbranch[n].lnum == 0 &&
+ znode->zbranch[n].len != 0) {
+ err = 18;
+ goto out;
+ }
+
+ if (znode->zbranch[n].lnum == 0 &&
+ znode->zbranch[n].offs != 0) {
+ err = 19;
+ goto out;
+ }
+
+ if (znode->level != 0 && znode->zbranch[n].znode)
+ if (znode->zbranch[n].znode->parent != znode) {
+ err = 20;
+ goto out;
+ }
+ }
+
+ return 0;
+
+out:
+ ubifs_err("failed, error %d", err);
+ ubifs_msg("dump of the znode");
+ dbg_dump_znode(c, znode);
+ if (zp) {
+ ubifs_msg("dump of the parent znode");
+ dbg_dump_znode(c, zp);
+ }
+ dump_stack();
+ return -EINVAL;
+}
+
+/**
+ * dbg_check_tnc - check TNC tree.
+ * @c: UBIFS file-system description object
+ * @extra: do extra checks that are possible at start commit
+ *
+ * This function traverses whole TNC tree and checks every znode. Returns zero
+ * if everything is all right and %-EINVAL if something is wrong with TNC.
+ */
+int dbg_check_tnc(struct ubifs_info *c, int extra)
+{
+ struct ubifs_znode *znode;
+ long clean_cnt = 0, dirty_cnt = 0;
+ int err, last;
+
+ if (!(ubifs_chk_flags & UBIFS_CHK_TNC))
+ return 0;
+
+ ubifs_assert(mutex_is_locked(&c->tnc_mutex));
+ if (!c->zroot.znode)
+ return 0;
+
+ znode = ubifs_tnc_postorder_first(c->zroot.znode);
+ while (1) {
+ struct ubifs_znode *prev;
+ struct ubifs_zbranch *zbr;
+
+ if (!znode->parent)
+ zbr = &c->zroot;
+ else
+ zbr = &znode->parent->zbranch[znode->iip];
+
+ err = dbg_check_znode(c, zbr);
+ if (err)
+ return err;
+
+ if (extra) {
+ if (ubifs_zn_dirty(znode))
+ dirty_cnt += 1;
+ else
+ clean_cnt += 1;
+ }
+
+ prev = znode;
+ znode = ubifs_tnc_postorder_next(znode);
+ if (!znode)
+ break;
+
+ /*
+ * If the last key of this znode is equivalent to the first key
+ * of the next znode (collision), then check order of the keys.
+ */
+ last = prev->child_cnt - 1;
+ if (prev->level == 0 && znode->level == 0 && !c->replaying &&
+ !keys_cmp(c, &prev->zbranch[last].key,
+ &znode->zbranch[0].key)) {
+ err = dbg_check_key_order(c, &prev->zbranch[last],
+ &znode->zbranch[0]);
+ if (err < 0)
+ return err;
+ if (err) {
+ ubifs_msg("first znode");
+ dbg_dump_znode(c, prev);
+ ubifs_msg("second znode");
+ dbg_dump_znode(c, znode);
+ return -EINVAL;
+ }
+ }
+ }
+
+ if (extra) {
+ if (clean_cnt != atomic_long_read(&c->clean_zn_cnt)) {
+ ubifs_err("incorrect clean_zn_cnt %ld, calculated %ld",
+ atomic_long_read(&c->clean_zn_cnt),
+ clean_cnt);
+ return -EINVAL;
+ }
+ if (dirty_cnt != atomic_long_read(&c->dirty_zn_cnt)) {
+ ubifs_err("incorrect dirty_zn_cnt %ld, calculated %ld",
+ atomic_long_read(&c->dirty_zn_cnt),
+ dirty_cnt);
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * dbg_walk_index - walk the on-flash index.
+ * @c: UBIFS file-system description object
+ * @leaf_cb: called for each leaf node
+ * @znode_cb: called for each indexing node
+ * @priv: private date which is passed to callbacks
+ *
+ * This function walks the UBIFS index and calls the @leaf_cb for each leaf
+ * node and @znode_cb for each indexing node. Returns zero in case of success
+ * and a negative error code in case of failure.
+ *
+ * It would be better if this function removed every znode it pulled to into
+ * the TNC, so that the behavior more closely matched the non-debugging
+ * behavior.
+ */
+int dbg_walk_index(struct ubifs_info *c, dbg_leaf_callback leaf_cb,
+ dbg_znode_callback znode_cb, void *priv)
+{
+ int err;
+ struct ubifs_zbranch *zbr;
+ struct ubifs_znode *znode, *child;
+
+ mutex_lock(&c->tnc_mutex);
+ /* If the root indexing node is not in TNC - pull it */
+ if (!c->zroot.znode) {
+ c->zroot.znode = ubifs_load_znode(c, &c->zroot, NULL, 0);
+ if (IS_ERR(c->zroot.znode)) {
+ err = PTR_ERR(c->zroot.znode);
+ c->zroot.znode = NULL;
+ goto out_unlock;
+ }
+ }
+
+ /*
+ * We are going to traverse the indexing tree in the postorder manner.
+ * Go down and find the leftmost indexing node where we are going to
+ * start from.
+ */
+ znode = c->zroot.znode;
+ while (znode->level > 0) {
+ zbr = &znode->zbranch[0];
+ child = zbr->znode;
+ if (!child) {
+ child = ubifs_load_znode(c, zbr, znode, 0);
+ if (IS_ERR(child)) {
+ err = PTR_ERR(child);
+ goto out_unlock;
+ }
+ zbr->znode = child;
+ }
+
+ znode = child;
+ }
+
+ /* Iterate over all indexing nodes */
+ while (1) {
+ int idx;
+
+ cond_resched();
+
+ if (znode_cb) {
+ err = znode_cb(c, znode, priv);
+ if (err) {
+ ubifs_err("znode checking function returned "
+ "error %d", err);
+ dbg_dump_znode(c, znode);
+ goto out_dump;
+ }
+ }
+ if (leaf_cb && znode->level == 0) {
+ for (idx = 0; idx < znode->child_cnt; idx++) {
+ zbr = &znode->zbranch[idx];
+ err = leaf_cb(c, zbr, priv);
+ if (err) {
+ ubifs_err("leaf checking function "
+ "returned error %d, for leaf "
+ "at LEB %d:%d",
+ err, zbr->lnum, zbr->offs);
+ goto out_dump;
+ }
+ }
+ }
+
+ if (!znode->parent)
+ break;
+
+ idx = znode->iip + 1;
+ znode = znode->parent;
+ if (idx < znode->child_cnt) {
+ /* Switch to the next index in the parent */
+ zbr = &znode->zbranch[idx];
+ child = zbr->znode;
+ if (!child) {
+ child = ubifs_load_znode(c, zbr, znode, idx);
+ if (IS_ERR(child)) {
+ err = PTR_ERR(child);
+ goto out_unlock;
+ }
+ zbr->znode = child;
+ }
+ znode = child;
+ } else
+ /*
+ * This is the last child, switch to the parent and
+ * continue.
+ */
+ continue;
+
+ /* Go to the lowest leftmost znode in the new sub-tree */
+ while (znode->level > 0) {
+ zbr = &znode->zbranch[0];
+ child = zbr->znode;
+ if (!child) {
+ child = ubifs_load_znode(c, zbr, znode, 0);
+ if (IS_ERR(child)) {
+ err = PTR_ERR(child);
+ goto out_unlock;
+ }
+ zbr->znode = child;
+ }
+ znode = child;
+ }
+ }
+
+ mutex_unlock(&c->tnc_mutex);
+ return 0;
+
+out_dump:
+ if (znode->parent)
+ zbr = &znode->parent->zbranch[znode->iip];
+ else
+ zbr = &c->zroot;
+ ubifs_msg("dump of znode at LEB %d:%d", zbr->lnum, zbr->offs);
+ dbg_dump_znode(c, znode);
+out_unlock:
+ mutex_unlock(&c->tnc_mutex);
+ return err;
+}
+
+/**
+ * add_size - add znode size to partially calculated index size.
+ * @c: UBIFS file-system description object
+ * @znode: znode to add size for
+ * @priv: partially calculated index size
+ *
+ * This is a helper function for 'dbg_check_idx_size()' which is called for
+ * every indexing node and adds its size to the 'long long' variable pointed to
+ * by @priv.
+ */
+static int add_size(struct ubifs_info *c, struct ubifs_znode *znode, void *priv)
+{
+ long long *idx_size = priv;
+ int add;
+
+ add = ubifs_idx_node_sz(c, znode->child_cnt);
+ add = ALIGN(add, 8);
+ *idx_size += add;
+ return 0;
+}
+
+/**
+ * dbg_check_idx_size - check index size.
+ * @c: UBIFS file-system description object
+ * @idx_size: size to check
+ *
+ * This function walks the UBIFS index, calculates its size and checks that the
+ * size is equivalent to @idx_size. Returns zero in case of success and a
+ * negative error code in case of failure.
+ */
+int dbg_check_idx_size(struct ubifs_info *c, long long idx_size)
+{
+ int err;
+ long long calc = 0;
+
+ if (!(ubifs_chk_flags & UBIFS_CHK_IDX_SZ))
+ return 0;
+
+ err = dbg_walk_index(c, NULL, add_size, &calc);
+ if (err) {
+ ubifs_err("error %d while walking the index", err);
+ return err;
+ }
+
+ if (calc != idx_size) {
+ ubifs_err("index size check failed: calculated size is %lld, "
+ "should be %lld", calc, idx_size);
+ dump_stack();
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/**
+ * struct fsck_inode - information about an inode used when checking the file-system.
+ * @rb: link in the RB-tree of inodes
+ * @inum: inode number
+ * @mode: inode type, permissions, etc
+ * @nlink: inode link count
+ * @xattr_cnt: count of extended attributes
+ * @references: how many directory/xattr entries refer this inode (calculated
+ * while walking the index)
+ * @calc_cnt: for directory inode count of child directories
+ * @size: inode size (read from on-flash inode)
+ * @xattr_sz: summary size of all extended attributes (read from on-flash
+ * inode)
+ * @calc_sz: for directories calculated directory size
+ * @calc_xcnt: count of extended attributes
+ * @calc_xsz: calculated summary size of all extended attributes
+ * @xattr_nms: sum of lengths of all extended attribute names belonging to this
+ * inode (read from on-flash inode)
+ * @calc_xnms: calculated sum of lengths of all extended attribute names
+ */
+struct fsck_inode {
+ struct rb_node rb;
+ ino_t inum;
+ umode_t mode;
+ unsigned int nlink;
+ unsigned int xattr_cnt;
+ int references;
+ int calc_cnt;
+ long long size;
+ unsigned int xattr_sz;
+ long long calc_sz;
+ long long calc_xcnt;
+ long long calc_xsz;
+ unsigned int xattr_nms;
+ long long calc_xnms;
+};
+
+/**
+ * struct fsck_data - private FS checking information.
+ * @inodes: RB-tree of all inodes (contains @struct fsck_inode objects)
+ */
+struct fsck_data {
+ struct rb_root inodes;
+};
+
+/**
+ * add_inode - add inode information to RB-tree of inodes.
+ * @c: UBIFS file-system description object
+ * @fsckd: FS checking information
+ * @ino: raw UBIFS inode to add
+ *
+ * This is a helper function for 'check_leaf()' which adds information about
+ * inode @ino to the RB-tree of inodes. Returns inode information pointer in
+ * case of success and a negative error code in case of failure.
+ */
+static struct fsck_inode *add_inode(struct ubifs_info *c,
+ struct fsck_data *fsckd,
+ struct ubifs_ino_node *ino)
+{
+ struct rb_node **p, *parent = NULL;
+ struct fsck_inode *fscki;
+ ino_t inum = key_inum_flash(c, &ino->key);
+
+ p = &fsckd->inodes.rb_node;
+ while (*p) {
+ parent = *p;
+ fscki = rb_entry(parent, struct fsck_inode, rb);
+ if (inum < fscki->inum)
+ p = &(*p)->rb_left;
+ else if (inum > fscki->inum)
+ p = &(*p)->rb_right;
+ else
+ return fscki;
+ }
+
+ if (inum > c->highest_inum) {
+ ubifs_err("too high inode number, max. is %lu",
+ c->highest_inum);
+ return ERR_PTR(-EINVAL);
+ }
+
+ fscki = kzalloc(sizeof(struct fsck_inode), GFP_NOFS);
+ if (!fscki)
+ return ERR_PTR(-ENOMEM);
+
+ fscki->inum = inum;
+ fscki->nlink = le32_to_cpu(ino->nlink);
+ fscki->size = le64_to_cpu(ino->size);
+ fscki->xattr_cnt = le32_to_cpu(ino->xattr_cnt);
+ fscki->xattr_sz = le32_to_cpu(ino->xattr_size);
+ fscki->xattr_nms = le32_to_cpu(ino->xattr_names);
+ fscki->mode = le32_to_cpu(ino->mode);
+ if (S_ISDIR(fscki->mode)) {
+ fscki->calc_sz = UBIFS_INO_NODE_SZ;
+ fscki->calc_cnt = 2;
+ }
+ rb_link_node(&fscki->rb, parent, p);
+ rb_insert_color(&fscki->rb, &fsckd->inodes);
+ return fscki;
+}
+
+/**
+ * search_inode - search inode in the RB-tree of inodes.
+ * @fsckd: FS checking information
+ * @inum: inode number to search
+ *
+ * This is a helper function for 'check_leaf()' which searches inode @inum in
+ * the RB-tree of inodes and returns an inode information pointer or %NULL if
+ * the inode was not found.
+ */
+static struct fsck_inode *search_inode(struct fsck_data *fsckd, ino_t inum)
+{
+ struct rb_node *p;
+ struct fsck_inode *fscki;
+
+ p = fsckd->inodes.rb_node;
+ while (p) {
+ fscki = rb_entry(p, struct fsck_inode, rb);
+ if (inum < fscki->inum)
+ p = p->rb_left;
+ else if (inum > fscki->inum)
+ p = p->rb_right;
+ else
+ return fscki;
+ }
+ return NULL;
+}
+
+/**
+ * read_add_inode - read inode node and add it to RB-tree of inodes.
+ * @c: UBIFS file-system description object
+ * @fsckd: FS checking information
+ * @inum: inode number to read
+ *
+ * This is a helper function for 'check_leaf()' which finds inode node @inum in
+ * the index, reads it, and adds it to the RB-tree of inodes. Returns inode
+ * information pointer in case of success and a negative error code in case of
+ * failure.
+ */
+static struct fsck_inode *read_add_inode(struct ubifs_info *c,
+ struct fsck_data *fsckd, ino_t inum)
+{
+ int n, err;
+ union ubifs_key key;
+ struct ubifs_znode *znode;
+ struct ubifs_zbranch *zbr;
+ struct ubifs_ino_node *ino;
+ struct fsck_inode *fscki;
+
+ fscki = search_inode(fsckd, inum);
+ if (fscki)
+ return fscki;
+
+ ino_key_init(c, &key, inum);
+ err = ubifs_lookup_level0(c, &key, &znode, &n);
+ if (!err) {
+ ubifs_err("inode %lu not found in index", inum);
+ return ERR_PTR(-ENOENT);
+ } else if (err < 0) {
+ ubifs_err("error %d while looking up inode %lu", err, inum);
+ return ERR_PTR(err);
+ }
+
+ zbr = &znode->zbranch[n];
+ if (zbr->len < UBIFS_INO_NODE_SZ) {
+ ubifs_err("bad node %lu node length %d", inum, zbr->len);
+ return ERR_PTR(-EINVAL);
+ }
+
+ ino = kmalloc(zbr->len, GFP_NOFS);
+ if (!ino)
+ return ERR_PTR(-ENOMEM);
+
+ err = ubifs_tnc_read_node(c, zbr, ino);
+ if (err) {
+ ubifs_err("cannot read inode node at LEB %d:%d, error %d",
+ zbr->lnum, zbr->offs, err);
+ kfree(ino);
+ return ERR_PTR(err);
+ }
+
+ fscki = add_inode(c, fsckd, ino);
+ kfree(ino);
+ if (IS_ERR(fscki)) {
+ ubifs_err("error %ld while adding inode %lu node",
+ PTR_ERR(fscki), inum);
+ return fscki;
+ }
+
+ return fscki;
+}
+
+/**
+ * check_leaf - check leaf node.
+ * @c: UBIFS file-system description object
+ * @zbr: zbranch of the leaf node to check
+ * @priv: FS checking information
+ *
+ * This is a helper function for 'dbg_check_filesystem()' which is called for
+ * every single leaf node while walking the indexing tree. It checks that the
+ * leaf node referred from the indexing tree exists, has correct CRC, and does
+ * some other basic validation. This function is also responsible for building
+ * an RB-tree of inodes - it adds all inodes into the RB-tree. It also
+ * calculates reference count, size, etc for each inode in order to later
+ * compare them to the information stored inside the inodes and detect possible
+ * inconsistencies. Returns zero in case of success and a negative error code
+ * in case of failure.
+ */
+static int check_leaf(struct ubifs_info *c, struct ubifs_zbranch *zbr,
+ void *priv)
+{
+ ino_t inum;
+ void *node;
+ struct ubifs_ch *ch;
+ int err, type = key_type(c, &zbr->key);
+ struct fsck_inode *fscki;
+
+ if (zbr->len < UBIFS_CH_SZ) {
+ ubifs_err("bad leaf length %d (LEB %d:%d)",
+ zbr->len, zbr->lnum, zbr->offs);
+ return -EINVAL;
+ }
+
+ node = kmalloc(zbr->len, GFP_NOFS);
+ if (!node)
+ return -ENOMEM;
+
+ err = ubifs_tnc_read_node(c, zbr, node);
+ if (err) {
+ ubifs_err("cannot read leaf node at LEB %d:%d, error %d",
+ zbr->lnum, zbr->offs, err);
+ goto out_free;
+ }
+
+ /* If this is an inode node, add it to RB-tree of inodes */
+ if (type == UBIFS_INO_KEY) {
+ fscki = add_inode(c, priv, node);
+ if (IS_ERR(fscki)) {
+ err = PTR_ERR(fscki);
+ ubifs_err("error %d while adding inode node", err);
+ goto out_dump;
+ }
+ goto out;
+ }
+
+ if (type != UBIFS_DENT_KEY && type != UBIFS_XENT_KEY &&
+ type != UBIFS_DATA_KEY) {
+ ubifs_err("unexpected node type %d at LEB %d:%d",
+ type, zbr->lnum, zbr->offs);
+ err = -EINVAL;
+ goto out_free;
+ }
+
+ ch = node;
+ if (le64_to_cpu(ch->sqnum) > c->max_sqnum) {
+ ubifs_err("too high sequence number, max. is %llu",
+ c->max_sqnum);
+ err = -EINVAL;
+ goto out_dump;
+ }
+
+ if (type == UBIFS_DATA_KEY) {
+ long long blk_offs;
+ struct ubifs_data_node *dn = node;
+
+ /*
+ * Search the inode node this data node belongs to and insert
+ * it to the RB-tree of inodes.
+ */
+ inum = key_inum_flash(c, &dn->key);
+ fscki = read_add_inode(c, priv, inum);
+ if (IS_ERR(fscki)) {
+ err = PTR_ERR(fscki);
+ ubifs_err("error %d while processing data node and "
+ "trying to find inode node %lu", err, inum);
+ goto out_dump;
+ }
+
+ /* Make sure the data node is within inode size */
+ blk_offs = key_block_flash(c, &dn->key);
+ blk_offs <<= UBIFS_BLOCK_SHIFT;
+ blk_offs += le32_to_cpu(dn->size);
+ if (blk_offs > fscki->size) {
+ ubifs_err("data node at LEB %d:%d is not within inode "
+ "size %lld", zbr->lnum, zbr->offs,
+ fscki->size);
+ err = -EINVAL;
+ goto out_dump;
+ }
+ } else {
+ int nlen;
+ struct ubifs_dent_node *dent = node;
+ struct fsck_inode *fscki1;
+
+ err = ubifs_validate_entry(c, dent);
+ if (err)
+ goto out_dump;
+
+ /*
+ * Search the inode node this entry refers to and the parent
+ * inode node and insert them to the RB-tree of inodes.
+ */
+ inum = le64_to_cpu(dent->inum);
+ fscki = read_add_inode(c, priv, inum);
+ if (IS_ERR(fscki)) {
+ err = PTR_ERR(fscki);
+ ubifs_err("error %d while processing entry node and "
+ "trying to find inode node %lu", err, inum);
+ goto out_dump;
+ }
+
+ /* Count how many direntries or xentries refers this inode */
+ fscki->references += 1;
+
+ inum = key_inum_flash(c, &dent->key);
+ fscki1 = read_add_inode(c, priv, inum);
+ if (IS_ERR(fscki1)) {
+ err = PTR_ERR(fscki);
+ ubifs_err("error %d while processing entry node and "
+ "trying to find parent inode node %lu",
+ err, inum);
+ goto out_dump;
+ }
+
+ nlen = le16_to_cpu(dent->nlen);
+ if (type == UBIFS_XENT_KEY) {
+ fscki1->calc_xcnt += 1;
+ fscki1->calc_xsz += CALC_DENT_SIZE(nlen);
+ fscki1->calc_xsz += CALC_XATTR_BYTES(fscki->size);
+ fscki1->calc_xnms += nlen;
+ } else {
+ fscki1->calc_sz += CALC_DENT_SIZE(nlen);
+ if (dent->type == UBIFS_ITYPE_DIR)
+ fscki1->calc_cnt += 1;
+ }
+ }
+
+out:
+ kfree(node);
+ return 0;
+
+out_dump:
+ ubifs_msg("dump of node at LEB %d:%d", zbr->lnum, zbr->offs);
+ dbg_dump_node(c, node);
+out_free:
+ kfree(node);
+ return err;
+}
+
+/**
+ * free_inodes - free RB-tree of inodes.
+ * @fsckd: FS checking information
+ */
+static void free_inodes(struct fsck_data *fsckd)
+{
+ struct rb_node *this = fsckd->inodes.rb_node;
+ struct fsck_inode *fscki;
+
+ while (this) {
+ if (this->rb_left)
+ this = this->rb_left;
+ else if (this->rb_right)
+ this = this->rb_right;
+ else {
+ fscki = rb_entry(this, struct fsck_inode, rb);
+ this = rb_parent(this);
+ if (this) {
+ if (this->rb_left == &fscki->rb)
+ this->rb_left = NULL;
+ else
+ this->rb_right = NULL;
+ }
+ kfree(fscki);
+ }
+ }
+}
+
+/**
+ * check_inodes - checks all inodes.
+ * @c: UBIFS file-system description object
+ * @fsckd: FS checking information
+ *
+ * This is a helper function for 'dbg_check_filesystem()' which walks the
+ * RB-tree of inodes after the index scan has been finished, and checks that
+ * inode nlink, size, etc are correct. Returns zero if inodes are fine,
+ * %-EINVAL if not, and a negative error code in case of failure.
+ */
+static int check_inodes(struct ubifs_info *c, struct fsck_data *fsckd)
+{
+ int n, err;
+ union ubifs_key key;
+ struct ubifs_znode *znode;
+ struct ubifs_zbranch *zbr;
+ struct ubifs_ino_node *ino;
+ struct fsck_inode *fscki;
+ struct rb_node *this = rb_first(&fsckd->inodes);
+
+ while (this) {
+ fscki = rb_entry(this, struct fsck_inode, rb);
+ this = rb_next(this);
+
+ if (S_ISDIR(fscki->mode)) {
+ /*
+ * Directories have to have exactly one reference (they
+ * cannot have hardlinks), although root inode is an
+ * exception.
+ */
+ if (fscki->inum != UBIFS_ROOT_INO &&
+ fscki->references != 1) {
+ ubifs_err("directory inode %lu has %d "
+ "direntries which refer it, but "
+ "should be 1", fscki->inum,
+ fscki->references);
+ goto out_dump;
+ }
+ if (fscki->inum == UBIFS_ROOT_INO &&
+ fscki->references != 0) {
+ ubifs_err("root inode %lu has non-zero (%d) "
+ "direntries which refer it",
+ fscki->inum, fscki->references);
+ goto out_dump;
+ }
+ if (fscki->calc_sz != fscki->size) {
+ ubifs_err("directory inode %lu size is %lld, "
+ "but calculated size is %lld",
+ fscki->inum, fscki->size,
+ fscki->calc_sz);
+ goto out_dump;
+ }
+ if (fscki->calc_cnt != fscki->nlink) {
+ ubifs_err("directory inode %lu nlink is %d, "
+ "but calculated nlink is %d",
+ fscki->inum, fscki->nlink,
+ fscki->calc_cnt);
+ goto out_dump;
+ }
+ } else {
+ if (fscki->references != fscki->nlink) {
+ ubifs_err("inode %lu nlink is %d, but "
+ "calculated nlink is %d", fscki->inum,
+ fscki->nlink, fscki->references);
+ goto out_dump;
+ }
+ }
+ if (fscki->xattr_sz != fscki->calc_xsz) {
+ ubifs_err("inode %lu has xattr size %u, but "
+ "calculated size is %lld",
+ fscki->inum, fscki->xattr_sz,
+ fscki->calc_xsz);
+ goto out_dump;
+ }
+ if (fscki->xattr_cnt != fscki->calc_xcnt) {
+ ubifs_err("inode %lu has %u xattrs, but "
+ "calculated count is %lld", fscki->inum,
+ fscki->xattr_cnt, fscki->calc_xcnt);
+ goto out_dump;
+ }
+ if (fscki->xattr_nms != fscki->calc_xnms) {
+ ubifs_err("inode %lu has xattr names' size %u, but "
+ "calculated names' size is %lld",
+ fscki->inum, fscki->xattr_nms,
+ fscki->calc_xnms);
+ goto out_dump;
+ }
+ }
+
+ return 0;
+
+out_dump:
+ /* Read the bad inode and dump it */
+ ino_key_init(c, &key, fscki->inum);
+ err = ubifs_lookup_level0(c, &key, &znode, &n);
+ if (!err) {
+ ubifs_err("inode %lu not found in index", fscki->inum);
+ return -ENOENT;
+ } else if (err < 0) {
+ ubifs_err("error %d while looking up inode %lu",
+ err, fscki->inum);
+ return err;
+ }
+
+ zbr = &znode->zbranch[n];
+ ino = kmalloc(zbr->len, GFP_NOFS);
+ if (!ino)
+ return -ENOMEM;
+
+ err = ubifs_tnc_read_node(c, zbr, ino);
+ if (err) {
+ ubifs_err("cannot read inode node at LEB %d:%d, error %d",
+ zbr->lnum, zbr->offs, err);
+ kfree(ino);
+ return err;
+ }
+
+ ubifs_msg("dump of the inode %lu sitting in LEB %d:%d",
+ fscki->inum, zbr->lnum, zbr->offs);
+ dbg_dump_node(c, ino);
+ kfree(ino);
+ return -EINVAL;
+}
+
+/**
+ * dbg_check_filesystem - check the file-system.
+ * @c: UBIFS file-system description object
+ *
+ * This function checks the file system, namely:
+ * o makes sure that all leaf nodes exist and their CRCs are correct;
+ * o makes sure inode nlink, size, xattr size/count are correct (for all
+ * inodes).
+ *
+ * The function reads whole indexing tree and all nodes, so it is pretty
+ * heavy-weight. Returns zero if the file-system is consistent, %-EINVAL if
+ * not, and a negative error code in case of failure.
+ */
+int dbg_check_filesystem(struct ubifs_info *c)
+{
+ int err;
+ struct fsck_data fsckd;
+
+ if (!(ubifs_chk_flags & UBIFS_CHK_FS))
+ return 0;
+
+ fsckd.inodes = RB_ROOT;
+ err = dbg_walk_index(c, check_leaf, NULL, &fsckd);
+ if (err)
+ goto out_free;
+
+ err = check_inodes(c, &fsckd);
+ if (err)
+ goto out_free;
+
+ free_inodes(&fsckd);
+ return 0;
+
+out_free:
+ ubifs_err("file-system check failed with error %d", err);
+ dump_stack();
+ free_inodes(&fsckd);
+ return err;
+}
+
+static int invocation_cnt;
+
+int dbg_force_in_the_gaps(void)
+{
+ if (!dbg_force_in_the_gaps_enabled)
+ return 0;
+ /* Force in-the-gaps every 8th commit */
+ return !((invocation_cnt++) & 0x7);
+}
+
+/* Failure mode for recovery testing */
+
+#define chance(n, d) (simple_rand() <= (n) * 32768LL / (d))
+
+struct failure_mode_info {
+ struct list_head list;
+ struct ubifs_info *c;
+};
+
+static LIST_HEAD(fmi_list);
+static DEFINE_SPINLOCK(fmi_lock);
+
+static unsigned int next;
+
+static int simple_rand(void)
+{
+ if (next == 0)
+ next = current->pid;
+ next = next * 1103515245 + 12345;
+ return (next >> 16) & 32767;
+}
+
+void dbg_failure_mode_registration(struct ubifs_info *c)
+{
+ struct failure_mode_info *fmi;
+
+ fmi = kmalloc(sizeof(struct failure_mode_info), GFP_NOFS);
+ if (!fmi) {
+ dbg_err("Failed to register failure mode - no memory");
+ return;
+ }
+ fmi->c = c;
+ spin_lock(&fmi_lock);
+ list_add_tail(&fmi->list, &fmi_list);
+ spin_unlock(&fmi_lock);
+}
+
+void dbg_failure_mode_deregistration(struct ubifs_info *c)
+{
+ struct failure_mode_info *fmi, *tmp;
+
+ spin_lock(&fmi_lock);
+ list_for_each_entry_safe(fmi, tmp, &fmi_list, list)
+ if (fmi->c == c) {
+ list_del(&fmi->list);
+ kfree(fmi);
+ }
+ spin_unlock(&fmi_lock);
+}
+
+static struct ubifs_info *dbg_find_info(struct ubi_volume_desc *desc)
+{
+ struct failure_mode_info *fmi;
+
+ spin_lock(&fmi_lock);
+ list_for_each_entry(fmi, &fmi_list, list)
+ if (fmi->c->ubi == desc) {
+ struct ubifs_info *c = fmi->c;
+
+ spin_unlock(&fmi_lock);
+ return c;
+ }
+ spin_unlock(&fmi_lock);
+ return NULL;
+}
+
+static int in_failure_mode(struct ubi_volume_desc *desc)
+{
+ struct ubifs_info *c = dbg_find_info(desc);
+
+ if (c && dbg_failure_mode)
+ return c->failure_mode;
+ return 0;
+}
+
+static int do_fail(struct ubi_volume_desc *desc, int lnum, int write)
+{
+ struct ubifs_info *c = dbg_find_info(desc);
+
+ if (!c || !dbg_failure_mode)
+ return 0;
+ if (c->failure_mode)
+ return 1;
+ if (!c->fail_cnt) {
+ /* First call - decide delay to failure */
+ if (chance(1, 2)) {
+ unsigned int delay = 1 << (simple_rand() >> 11);
+
+ if (chance(1, 2)) {
+ c->fail_delay = 1;
+ c->fail_timeout = jiffies +
+ msecs_to_jiffies(delay);
+ dbg_rcvry("failing after %ums", delay);
+ } else {
+ c->fail_delay = 2;
+ c->fail_cnt_max = delay;
+ dbg_rcvry("failing after %u calls", delay);
+ }
+ }
+ c->fail_cnt += 1;
+ }
+ /* Determine if failure delay has expired */
+ if (c->fail_delay == 1) {
+ if (time_before(jiffies, c->fail_timeout))
+ return 0;
+ } else if (c->fail_delay == 2)
+ if (c->fail_cnt++ < c->fail_cnt_max)
+ return 0;
+ if (lnum == UBIFS_SB_LNUM) {
+ if (write) {
+ if (chance(1, 2))
+ return 0;
+ } else if (chance(19, 20))
+ return 0;
+ dbg_rcvry("failing in super block LEB %d", lnum);
+ } else if (lnum == UBIFS_MST_LNUM || lnum == UBIFS_MST_LNUM + 1) {
+ if (chance(19, 20))
+ return 0;
+ dbg_rcvry("failing in master LEB %d", lnum);
+ } else if (lnum >= UBIFS_LOG_LNUM && lnum <= c->log_last) {
+ if (write) {
+ if (chance(99, 100))
+ return 0;
+ } else if (chance(399, 400))
+ return 0;
+ dbg_rcvry("failing in log LEB %d", lnum);
+ } else if (lnum >= c->lpt_first && lnum <= c->lpt_last) {
+ if (write) {
+ if (chance(7, 8))
+ return 0;
+ } else if (chance(19, 20))
+ return 0;
+ dbg_rcvry("failing in LPT LEB %d", lnum);
+ } else if (lnum >= c->orph_first && lnum <= c->orph_last) {
+ if (write) {
+ if (chance(1, 2))
+ return 0;
+ } else if (chance(9, 10))
+ return 0;
+ dbg_rcvry("failing in orphan LEB %d", lnum);
+ } else if (lnum == c->ihead_lnum) {
+ if (chance(99, 100))
+ return 0;
+ dbg_rcvry("failing in index head LEB %d", lnum);
+ } else if (c->jheads && lnum == c->jheads[GCHD].wbuf.lnum) {
+ if (chance(9, 10))
+ return 0;
+ dbg_rcvry("failing in GC head LEB %d", lnum);
+ } else if (write && !RB_EMPTY_ROOT(&c->buds) &&
+ !ubifs_search_bud(c, lnum)) {
+ if (chance(19, 20))
+ return 0;
+ dbg_rcvry("failing in non-bud LEB %d", lnum);
+ } else if (c->cmt_state == COMMIT_RUNNING_BACKGROUND ||
+ c->cmt_state == COMMIT_RUNNING_REQUIRED) {
+ if (chance(999, 1000))
+ return 0;
+ dbg_rcvry("failing in bud LEB %d commit running", lnum);
+ } else {
+ if (chance(9999, 10000))
+ return 0;
+ dbg_rcvry("failing in bud LEB %d commit not running", lnum);
+ }
+ ubifs_err("*** SETTING FAILURE MODE ON (LEB %d) ***", lnum);
+ c->failure_mode = 1;
+ dump_stack();
+ return 1;
+}
+
+static void cut_data(const void *buf, int len)
+{
+ int flen, i;
+ unsigned char *p = (void *)buf;
+
+ flen = (len * (long long)simple_rand()) >> 15;
+ for (i = flen; i < len; i++)
+ p[i] = 0xff;
+}
+
+int dbg_leb_read(struct ubi_volume_desc *desc, int lnum, char *buf, int offset,
+ int len, int check)
+{
+ if (in_failure_mode(desc))
+ return -EIO;
+ return ubi_leb_read(desc, lnum, buf, offset, len, check);
+}
+
+int dbg_leb_write(struct ubi_volume_desc *desc, int lnum, const void *buf,
+ int offset, int len, int dtype)
+{
+ int err;
+
+ if (in_failure_mode(desc))
+ return -EIO;
+ if (do_fail(desc, lnum, 1))
+ cut_data(buf, len);
+ err = ubi_leb_write(desc, lnum, buf, offset, len, dtype);
+ if (err)
+ return err;
+ if (in_failure_mode(desc))
+ return -EIO;
+ return 0;
+}
+
+int dbg_leb_change(struct ubi_volume_desc *desc, int lnum, const void *buf,
+ int len, int dtype)
+{
+ int err;
+
+ if (do_fail(desc, lnum, 1))
+ return -EIO;
+ err = ubi_leb_change(desc, lnum, buf, len, dtype);
+ if (err)
+ return err;
+ if (do_fail(desc, lnum, 1))
+ return -EIO;
+ return 0;
+}
+
+int dbg_leb_erase(struct ubi_volume_desc *desc, int lnum)
+{
+ int err;
+
+ if (do_fail(desc, lnum, 0))
+ return -EIO;
+ err = ubi_leb_erase(desc, lnum);
+ if (err)
+ return err;
+ if (do_fail(desc, lnum, 0))
+ return -EIO;
+ return 0;
+}
+
+int dbg_leb_unmap(struct ubi_volume_desc *desc, int lnum)
+{
+ int err;
+
+ if (do_fail(desc, lnum, 0))
+ return -EIO;
+ err = ubi_leb_unmap(desc, lnum);
+ if (err)
+ return err;
+ if (do_fail(desc, lnum, 0))
+ return -EIO;
+ return 0;
+}
+
+int dbg_is_mapped(struct ubi_volume_desc *desc, int lnum)
+{
+ if (in_failure_mode(desc))
+ return -EIO;
+ return ubi_is_mapped(desc, lnum);
+}
+
+int dbg_leb_map(struct ubi_volume_desc *desc, int lnum, int dtype)
+{
+ int err;
+
+ if (do_fail(desc, lnum, 0))
+ return -EIO;
+ err = ubi_leb_map(desc, lnum, dtype);
+ if (err)
+ return err;
+ if (do_fail(desc, lnum, 0))
+ return -EIO;
+ return 0;
+}
+
+#endif /* CONFIG_UBIFS_FS_DEBUG */
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ * Adrian Hunter
+ */
+
+#ifndef __UBIFS_DEBUG_H__
+#define __UBIFS_DEBUG_H__
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+
+#define UBIFS_DBG(op) op
+
+#define ubifs_assert(expr) do { \
+ if (unlikely(!(expr))) { \
+ printk(KERN_CRIT "UBIFS assert failed in %s at %u (pid %d)\n", \
+ __func__, __LINE__, current->pid); \
+ dbg_dump_stack(); \
+ } \
+} while (0)
+
+#define ubifs_assert_cmt_locked(c) do { \
+ if (unlikely(down_write_trylock(&(c)->commit_sem))) { \
+ up_write(&(c)->commit_sem); \
+ printk(KERN_CRIT "commit lock is not locked!\n"); \
+ ubifs_assert(0); \
+ } \
+} while (0)
+
+#define dbg_dump_stack() do { \
+ if (!dbg_failure_mode) \
+ dump_stack(); \
+} while (0)
+
+/* Generic debugging messages */
+#define dbg_msg(fmt, ...) do { \
+ spin_lock(&dbg_lock); \
+ printk(KERN_DEBUG "UBIFS DBG (pid %d): %s: " fmt "\n", current->pid, \
+ __func__, ##__VA_ARGS__); \
+ spin_unlock(&dbg_lock); \
+} while (0)
+
+#define dbg_do_msg(typ, fmt, ...) do { \
+ if (ubifs_msg_flags & typ) \
+ dbg_msg(fmt, ##__VA_ARGS__); \
+} while (0)
+
+#define dbg_err(fmt, ...) do { \
+ spin_lock(&dbg_lock); \
+ ubifs_err(fmt, ##__VA_ARGS__); \
+ spin_unlock(&dbg_lock); \
+} while (0)
+
+const char *dbg_key_str0(const struct ubifs_info *c,
+ const union ubifs_key *key);
+const char *dbg_key_str1(const struct ubifs_info *c,
+ const union ubifs_key *key);
+
+/*
+ * DBGKEY macros require dbg_lock to be held, which it is in the dbg message
+ * macros.
+ */
+#define DBGKEY(key) dbg_key_str0(c, (key))
+#define DBGKEY1(key) dbg_key_str1(c, (key))
+
+/* General messages */
+#define dbg_gen(fmt, ...) dbg_do_msg(UBIFS_MSG_GEN, fmt, ##__VA_ARGS__)
+
+/* Additional journal messages */
+#define dbg_jnl(fmt, ...) dbg_do_msg(UBIFS_MSG_JNL, fmt, ##__VA_ARGS__)
+
+/* Additional TNC messages */
+#define dbg_tnc(fmt, ...) dbg_do_msg(UBIFS_MSG_TNC, fmt, ##__VA_ARGS__)
+
+/* Additional lprops messages */
+#define dbg_lp(fmt, ...) dbg_do_msg(UBIFS_MSG_LP, fmt, ##__VA_ARGS__)
+
+/* Additional LEB find messages */
+#define dbg_find(fmt, ...) dbg_do_msg(UBIFS_MSG_FIND, fmt, ##__VA_ARGS__)
+
+/* Additional mount messages */
+#define dbg_mnt(fmt, ...) dbg_do_msg(UBIFS_MSG_MNT, fmt, ##__VA_ARGS__)
+
+/* Additional I/O messages */
+#define dbg_io(fmt, ...) dbg_do_msg(UBIFS_MSG_IO, fmt, ##__VA_ARGS__)
+
+/* Additional commit messages */
+#define dbg_cmt(fmt, ...) dbg_do_msg(UBIFS_MSG_CMT, fmt, ##__VA_ARGS__)
+
+/* Additional budgeting messages */
+#define dbg_budg(fmt, ...) dbg_do_msg(UBIFS_MSG_BUDG, fmt, ##__VA_ARGS__)
+
+/* Additional log messages */
+#define dbg_log(fmt, ...) dbg_do_msg(UBIFS_MSG_LOG, fmt, ##__VA_ARGS__)
+
+/* Additional gc messages */
+#define dbg_gc(fmt, ...) dbg_do_msg(UBIFS_MSG_GC, fmt, ##__VA_ARGS__)
+
+/* Additional scan messages */
+#define dbg_scan(fmt, ...) dbg_do_msg(UBIFS_MSG_SCAN, fmt, ##__VA_ARGS__)
+
+/* Additional recovery messages */
+#define dbg_rcvry(fmt, ...) dbg_do_msg(UBIFS_MSG_RCVRY, fmt, ##__VA_ARGS__)
+
+/*
+ * Debugging message type flags (must match msg_type_names in debug.c).
+ *
+ * UBIFS_MSG_GEN: general messages
+ * UBIFS_MSG_JNL: journal messages
+ * UBIFS_MSG_MNT: mount messages
+ * UBIFS_MSG_CMT: commit messages
+ * UBIFS_MSG_FIND: LEB find messages
+ * UBIFS_MSG_BUDG: budgeting messages
+ * UBIFS_MSG_GC: garbage collection messages
+ * UBIFS_MSG_TNC: TNC messages
+ * UBIFS_MSG_LP: lprops messages
+ * UBIFS_MSG_IO: I/O messages
+ * UBIFS_MSG_LOG: log messages
+ * UBIFS_MSG_SCAN: scan messages
+ * UBIFS_MSG_RCVRY: recovery messages
+ */
+enum {
+ UBIFS_MSG_GEN = 0x1,
+ UBIFS_MSG_JNL = 0x2,
+ UBIFS_MSG_MNT = 0x4,
+ UBIFS_MSG_CMT = 0x8,
+ UBIFS_MSG_FIND = 0x10,
+ UBIFS_MSG_BUDG = 0x20,
+ UBIFS_MSG_GC = 0x40,
+ UBIFS_MSG_TNC = 0x80,
+ UBIFS_MSG_LP = 0x100,
+ UBIFS_MSG_IO = 0x200,
+ UBIFS_MSG_LOG = 0x400,
+ UBIFS_MSG_SCAN = 0x800,
+ UBIFS_MSG_RCVRY = 0x1000,
+};
+
+/* Debugging message type flags for each default debug message level */
+#define UBIFS_MSG_LVL_0 0
+#define UBIFS_MSG_LVL_1 0x1
+#define UBIFS_MSG_LVL_2 0x7f
+#define UBIFS_MSG_LVL_3 0xffff
+
+/*
+ * Debugging check flags (must match chk_names in debug.c).
+ *
+ * UBIFS_CHK_GEN: general checks
+ * UBIFS_CHK_TNC: check TNC
+ * UBIFS_CHK_IDX_SZ: check index size
+ * UBIFS_CHK_ORPH: check orphans
+ * UBIFS_CHK_OLD_IDX: check the old index
+ * UBIFS_CHK_LPROPS: check lprops
+ * UBIFS_CHK_FS: check the file-system
+ */
+enum {
+ UBIFS_CHK_GEN = 0x1,
+ UBIFS_CHK_TNC = 0x2,
+ UBIFS_CHK_IDX_SZ = 0x4,
+ UBIFS_CHK_ORPH = 0x8,
+ UBIFS_CHK_OLD_IDX = 0x10,
+ UBIFS_CHK_LPROPS = 0x20,
+ UBIFS_CHK_FS = 0x40,
+};
+
+/*
+ * Special testing flags (must match tst_names in debug.c).
+ *
+ * UBIFS_TST_FORCE_IN_THE_GAPS: force the use of in-the-gaps method
+ * UBIFS_TST_RCVRY: failure mode for recovery testing
+ */
+enum {
+ UBIFS_TST_FORCE_IN_THE_GAPS = 0x2,
+ UBIFS_TST_RCVRY = 0x4,
+};
+
+#if CONFIG_UBIFS_FS_DEBUG_MSG_LVL == 1
+#define UBIFS_MSG_FLAGS_DEFAULT UBIFS_MSG_LVL_1
+#elif CONFIG_UBIFS_FS_DEBUG_MSG_LVL == 2
+#define UBIFS_MSG_FLAGS_DEFAULT UBIFS_MSG_LVL_2
+#elif CONFIG_UBIFS_FS_DEBUG_MSG_LVL == 3
+#define UBIFS_MSG_FLAGS_DEFAULT UBIFS_MSG_LVL_3
+#else
+#define UBIFS_MSG_FLAGS_DEFAULT UBIFS_MSG_LVL_0
+#endif
+
+#ifdef CONFIG_UBIFS_FS_DEBUG_CHKS
+#define UBIFS_CHK_FLAGS_DEFAULT 0xffffffff
+#else
+#define UBIFS_CHK_FLAGS_DEFAULT 0
+#endif
+
+extern spinlock_t dbg_lock;
+
+extern unsigned int ubifs_msg_flags;
+extern unsigned int ubifs_chk_flags;
+extern unsigned int ubifs_tst_flags;
+
+/* Dump functions */
+
+const char *dbg_ntype(int type);
+const char *dbg_cstate(int cmt_state);
+const char *dbg_get_key_dump(const struct ubifs_info *c,
+ const union ubifs_key *key);
+void dbg_dump_inode(const struct ubifs_info *c, const struct inode *inode);
+void dbg_dump_node(const struct ubifs_info *c, const void *node);
+void dbg_dump_budget_req(const struct ubifs_budget_req *req);
+void dbg_dump_lstats(const struct ubifs_lp_stats *lst);
+void dbg_dump_budg(struct ubifs_info *c);
+void dbg_dump_lprop(const struct ubifs_info *c, const struct ubifs_lprops *lp);
+void dbg_dump_lprops(struct ubifs_info *c);
+void dbg_dump_leb(const struct ubifs_info *c, int lnum);
+void dbg_dump_znode(const struct ubifs_info *c,
+ const struct ubifs_znode *znode);
+void dbg_dump_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat);
+void dbg_dump_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
+ struct ubifs_nnode *parent, int iip);
+void dbg_dump_tnc(struct ubifs_info *c);
+void dbg_dump_index(struct ubifs_info *c);
+
+/* Checking helper functions */
+
+typedef int (*dbg_leaf_callback)(struct ubifs_info *c,
+ struct ubifs_zbranch *zbr, void *priv);
+typedef int (*dbg_znode_callback)(struct ubifs_info *c,
+ struct ubifs_znode *znode, void *priv);
+
+int dbg_walk_index(struct ubifs_info *c, dbg_leaf_callback leaf_cb,
+ dbg_znode_callback znode_cb, void *priv);
+
+/* Checking functions */
+
+int dbg_check_lprops(struct ubifs_info *c);
+
+int dbg_old_index_check_init(struct ubifs_info *c, struct ubifs_zbranch *zroot);
+int dbg_check_old_index(struct ubifs_info *c, struct ubifs_zbranch *zroot);
+
+int dbg_check_cats(struct ubifs_info *c);
+
+int dbg_check_ltab(struct ubifs_info *c);
+
+int dbg_check_synced_i_size(struct inode *inode);
+
+int dbg_check_dir_size(struct ubifs_info *c, const struct inode *dir);
+
+int dbg_check_tnc(struct ubifs_info *c, int extra);
+
+int dbg_check_idx_size(struct ubifs_info *c, long long idx_size);
+
+int dbg_check_filesystem(struct ubifs_info *c);
+
+void dbg_check_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat,
+ int add_pos);
+
+int dbg_check_lprops(struct ubifs_info *c);
+int dbg_check_lpt_nodes(struct ubifs_info *c, struct ubifs_cnode *cnode,
+ int row, int col);
+
+/* Force the use of in-the-gaps method for testing */
+
+#define dbg_force_in_the_gaps_enabled \
+ (ubifs_tst_flags & UBIFS_TST_FORCE_IN_THE_GAPS)
+
+int dbg_force_in_the_gaps(void);
+
+/* Failure mode for recovery testing */
+
+#define dbg_failure_mode (ubifs_tst_flags & UBIFS_TST_RCVRY)
+
+void dbg_failure_mode_registration(struct ubifs_info *c);
+void dbg_failure_mode_deregistration(struct ubifs_info *c);
+
+#ifndef UBIFS_DBG_PRESERVE_UBI
+
+#define ubi_leb_read dbg_leb_read
+#define ubi_leb_write dbg_leb_write
+#define ubi_leb_change dbg_leb_change
+#define ubi_leb_erase dbg_leb_erase
+#define ubi_leb_unmap dbg_leb_unmap
+#define ubi_is_mapped dbg_is_mapped
+#define ubi_leb_map dbg_leb_map
+
+#endif
+
+int dbg_leb_read(struct ubi_volume_desc *desc, int lnum, char *buf, int offset,
+ int len, int check);
+int dbg_leb_write(struct ubi_volume_desc *desc, int lnum, const void *buf,
+ int offset, int len, int dtype);
+int dbg_leb_change(struct ubi_volume_desc *desc, int lnum, const void *buf,
+ int len, int dtype);
+int dbg_leb_erase(struct ubi_volume_desc *desc, int lnum);
+int dbg_leb_unmap(struct ubi_volume_desc *desc, int lnum);
+int dbg_is_mapped(struct ubi_volume_desc *desc, int lnum);
+int dbg_leb_map(struct ubi_volume_desc *desc, int lnum, int dtype);
+
+static inline int dbg_read(struct ubi_volume_desc *desc, int lnum, char *buf,
+ int offset, int len)
+{
+ return dbg_leb_read(desc, lnum, buf, offset, len, 0);
+}
+
+static inline int dbg_write(struct ubi_volume_desc *desc, int lnum,
+ const void *buf, int offset, int len)
+{
+ return dbg_leb_write(desc, lnum, buf, offset, len, UBI_UNKNOWN);
+}
+
+static inline int dbg_change(struct ubi_volume_desc *desc, int lnum,
+ const void *buf, int len)
+{
+ return dbg_leb_change(desc, lnum, buf, len, UBI_UNKNOWN);
+}
+
+#else /* !CONFIG_UBIFS_FS_DEBUG */
+
+#define UBIFS_DBG(op)
+#define ubifs_assert(expr) ({})
+#define ubifs_assert_cmt_locked(c)
+#define dbg_dump_stack()
+#define dbg_err(fmt, ...) ({})
+#define dbg_msg(fmt, ...) ({})
+#define dbg_key(c, key, fmt, ...) ({})
+
+#define dbg_gen(fmt, ...) ({})
+#define dbg_jnl(fmt, ...) ({})
+#define dbg_tnc(fmt, ...) ({})
+#define dbg_lp(fmt, ...) ({})
+#define dbg_find(fmt, ...) ({})
+#define dbg_mnt(fmt, ...) ({})
+#define dbg_io(fmt, ...) ({})
+#define dbg_cmt(fmt, ...) ({})
+#define dbg_budg(fmt, ...) ({})
+#define dbg_log(fmt, ...) ({})
+#define dbg_gc(fmt, ...) ({})
+#define dbg_scan(fmt, ...) ({})
+#define dbg_rcvry(fmt, ...) ({})
+
+#define dbg_ntype(type) ""
+#define dbg_cstate(cmt_state) ""
+#define dbg_get_key_dump(c, key) ({})
+#define dbg_dump_inode(c, inode) ({})
+#define dbg_dump_node(c, node) ({})
+#define dbg_dump_budget_req(req) ({})
+#define dbg_dump_lstats(lst) ({})
+#define dbg_dump_budg(c) ({})
+#define dbg_dump_lprop(c, lp) ({})
+#define dbg_dump_lprops(c) ({})
+#define dbg_dump_leb(c, lnum) ({})
+#define dbg_dump_znode(c, znode) ({})
+#define dbg_dump_heap(c, heap, cat) ({})
+#define dbg_dump_pnode(c, pnode, parent, iip) ({})
+#define dbg_dump_tnc(c) ({})
+#define dbg_dump_index(c) ({})
+
+#define dbg_walk_index(c, leaf_cb, znode_cb, priv) 0
+
+#define dbg_old_index_check_init(c, zroot) 0
+#define dbg_check_old_index(c, zroot) 0
+
+#define dbg_check_cats(c) 0
+
+#define dbg_check_ltab(c) 0
+
+#define dbg_check_synced_i_size(inode) 0
+
+#define dbg_check_dir_size(c, dir) 0
+
+#define dbg_check_tnc(c, x) 0
+
+#define dbg_check_idx_size(c, idx_size) 0
+
+#define dbg_check_filesystem(c) 0
+
+#define dbg_check_heap(c, heap, cat, add_pos) ({})
+
+#define dbg_check_lprops(c) 0
+#define dbg_check_lpt_nodes(c, cnode, row, col) 0
+
+#define dbg_force_in_the_gaps_enabled 0
+#define dbg_force_in_the_gaps() 0
+
+#define dbg_failure_mode 0
+#define dbg_failure_mode_registration(c) ({})
+#define dbg_failure_mode_deregistration(c) ({})
+
+#endif /* !CONFIG_UBIFS_FS_DEBUG */
+
+#endif /* !__UBIFS_DEBUG_H__ */
--- /dev/null
+/* * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ * Copyright (C) 2006, 2007 University of Szeged, Hungary
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ * Adrian Hunter
+ * Zoltan Sogor
+ */
+
+/*
+ * This file implements directory operations.
+ *
+ * All FS operations in this file allocate budget before writing anything to the
+ * media. If they fail to allocate it, the error is returned. The only
+ * exceptions are 'ubifs_unlink()' and 'ubifs_rmdir()' which keep working even
+ * if they unable to allocate the budget, because deletion %-ENOSPC failure is
+ * not what users are usually ready to get. UBIFS budgeting subsystem has some
+ * space reserved for these purposes.
+ *
+ * All operations in this file write all inodes which they change straight
+ * away, instead of marking them dirty. For example, 'ubifs_link()' changes
+ * @i_size of the parent inode and writes the parent inode together with the
+ * target inode. This was done to simplify file-system recovery which would
+ * otherwise be very difficult to do. The only exception is rename which marks
+ * the re-named inode dirty (because its @i_ctime is updated) but does not
+ * write it, but just marks it as dirty.
+ */
+
+#include "ubifs.h"
+
+/**
+ * inherit_flags - inherit flags of the parent inode.
+ * @dir: parent inode
+ * @mode: new inode mode flags
+ *
+ * This is a helper function for 'ubifs_new_inode()' which inherits flag of the
+ * parent directory inode @dir. UBIFS inodes inherit the following flags:
+ * o %UBIFS_COMPR_FL, which is useful to switch compression on/of on
+ * sub-directory basis;
+ * o %UBIFS_SYNC_FL - useful for the same reasons;
+ * o %UBIFS_DIRSYNC_FL - similar, but relevant only to directories.
+ *
+ * This function returns the inherited flags.
+ */
+static int inherit_flags(const struct inode *dir, int mode)
+{
+ int flags;
+ const struct ubifs_inode *ui = ubifs_inode(dir);
+
+ if (!S_ISDIR(dir->i_mode))
+ /*
+ * The parent is not a directory, which means that an extended
+ * attribute inode is being created. No flags.
+ */
+ return 0;
+
+ flags = ui->flags & (UBIFS_COMPR_FL | UBIFS_SYNC_FL | UBIFS_DIRSYNC_FL);
+ if (!S_ISDIR(mode))
+ /* The "DIRSYNC" flag only applies to directories */
+ flags &= ~UBIFS_DIRSYNC_FL;
+ return flags;
+}
+
+/**
+ * ubifs_new_inode - allocate new UBIFS inode object.
+ * @c: UBIFS file-system description object
+ * @dir: parent directory inode
+ * @mode: inode mode flags
+ *
+ * This function finds an unused inode number, allocates new inode and
+ * initializes it. Returns new inode in case of success and an error code in
+ * case of failure.
+ */
+struct inode *ubifs_new_inode(struct ubifs_info *c, const struct inode *dir,
+ int mode)
+{
+ struct inode *inode;
+ struct ubifs_inode *ui;
+
+ inode = new_inode(c->vfs_sb);
+ ui = ubifs_inode(inode);
+ if (!inode)
+ return ERR_PTR(-ENOMEM);
+
+ /*
+ * Set 'S_NOCMTIME' to prevent VFS form updating [mc]time of inodes and
+ * marking them dirty in file write path (see 'file_update_time()').
+ * UBIFS has to fully control "clean <-> dirty" transitions of inodes
+ * to make budgeting work.
+ */
+ inode->i_flags |= (S_NOCMTIME);
+
+ inode->i_uid = current->fsuid;
+ if (dir->i_mode & S_ISGID) {
+ inode->i_gid = dir->i_gid;
+ if (S_ISDIR(mode))
+ mode |= S_ISGID;
+ } else
+ inode->i_gid = current->fsgid;
+ inode->i_mode = mode;
+ inode->i_mtime = inode->i_atime = inode->i_ctime =
+ ubifs_current_time(inode);
+ inode->i_mapping->nrpages = 0;
+ /* Disable readahead */
+ inode->i_mapping->backing_dev_info = &c->bdi;
+
+ switch (mode & S_IFMT) {
+ case S_IFREG:
+ inode->i_mapping->a_ops = &ubifs_file_address_operations;
+ inode->i_op = &ubifs_file_inode_operations;
+ inode->i_fop = &ubifs_file_operations;
+ break;
+ case S_IFDIR:
+ inode->i_op = &ubifs_dir_inode_operations;
+ inode->i_fop = &ubifs_dir_operations;
+ inode->i_size = ui->ui_size = UBIFS_INO_NODE_SZ;
+ break;
+ case S_IFLNK:
+ inode->i_op = &ubifs_symlink_inode_operations;
+ break;
+ case S_IFSOCK:
+ case S_IFIFO:
+ case S_IFBLK:
+ case S_IFCHR:
+ inode->i_op = &ubifs_file_inode_operations;
+ break;
+ default:
+ BUG();
+ }
+
+ ui->flags = inherit_flags(dir, mode);
+ ubifs_set_inode_flags(inode);
+ if (S_ISREG(mode))
+ ui->compr_type = c->default_compr;
+ else
+ ui->compr_type = UBIFS_COMPR_NONE;
+ ui->synced_i_size = 0;
+
+ spin_lock(&c->cnt_lock);
+ /* Inode number overflow is currently not supported */
+ if (c->highest_inum >= INUM_WARN_WATERMARK) {
+ if (c->highest_inum >= INUM_WATERMARK) {
+ spin_unlock(&c->cnt_lock);
+ ubifs_err("out of inode numbers");
+ make_bad_inode(inode);
+ iput(inode);
+ return ERR_PTR(-EINVAL);
+ }
+ ubifs_warn("running out of inode numbers (current %lu, max %d)",
+ c->highest_inum, INUM_WATERMARK);
+ }
+
+ inode->i_ino = ++c->highest_inum;
+ inode->i_generation = ++c->vfs_gen;
+ /*
+ * The creation sequence number remains with this inode for its
+ * lifetime. All nodes for this inode have a greater sequence number,
+ * and so it is possible to distinguish obsolete nodes belonging to a
+ * previous incarnation of the same inode number - for example, for the
+ * purpose of rebuilding the index.
+ */
+ ui->creat_sqnum = ++c->max_sqnum;
+ spin_unlock(&c->cnt_lock);
+ return inode;
+}
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+
+static int dbg_check_name(struct ubifs_dent_node *dent, struct qstr *nm)
+{
+ if (!(ubifs_chk_flags & UBIFS_CHK_GEN))
+ return 0;
+ if (le16_to_cpu(dent->nlen) != nm->len)
+ return -EINVAL;
+ if (memcmp(dent->name, nm->name, nm->len))
+ return -EINVAL;
+ return 0;
+}
+
+#else
+
+#define dbg_check_name(dent, nm) 0
+
+#endif
+
+static struct dentry *ubifs_lookup(struct inode *dir, struct dentry *dentry,
+ struct nameidata *nd)
+{
+ int err;
+ union ubifs_key key;
+ struct inode *inode = NULL;
+ struct ubifs_dent_node *dent;
+ struct ubifs_info *c = dir->i_sb->s_fs_info;
+
+ dbg_gen("'%.*s' in dir ino %lu",
+ dentry->d_name.len, dentry->d_name.name, dir->i_ino);
+
+ if (dentry->d_name.len > UBIFS_MAX_NLEN)
+ return ERR_PTR(-ENAMETOOLONG);
+
+ dent = kmalloc(UBIFS_MAX_DENT_NODE_SZ, GFP_NOFS);
+ if (!dent)
+ return ERR_PTR(-ENOMEM);
+
+ dent_key_init(c, &key, dir->i_ino, &dentry->d_name);
+
+ err = ubifs_tnc_lookup_nm(c, &key, dent, &dentry->d_name);
+ if (err) {
+ /*
+ * Do not hash the direntry if parent 'i_nlink' is zero, because
+ * this has side-effects - '->delete_inode()' call will not be
+ * called for the parent orphan inode, because 'd_count' of its
+ * direntry will stay 1 (it'll be negative direntry I guess)
+ * and prevent 'iput_final()' until the dentry is destroyed due
+ * to unmount or memory pressure.
+ */
+ if (err == -ENOENT && dir->i_nlink != 0) {
+ dbg_gen("not found");
+ goto done;
+ }
+ goto out;
+ }
+
+ if (dbg_check_name(dent, &dentry->d_name)) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ inode = ubifs_iget(dir->i_sb, le64_to_cpu(dent->inum));
+ if (IS_ERR(inode)) {
+ /*
+ * This should not happen. Probably the file-system needs
+ * checking.
+ */
+ err = PTR_ERR(inode);
+ ubifs_err("dead directory entry '%.*s', error %d",
+ dentry->d_name.len, dentry->d_name.name, err);
+ ubifs_ro_mode(c, err);
+ goto out;
+ }
+
+done:
+ kfree(dent);
+ /*
+ * Note, d_splice_alias() would be required instead if we supported
+ * NFS.
+ */
+ d_add(dentry, inode);
+ return NULL;
+
+out:
+ kfree(dent);
+ return ERR_PTR(err);
+}
+
+static int ubifs_create(struct inode *dir, struct dentry *dentry, int mode,
+ struct nameidata *nd)
+{
+ struct inode *inode;
+ struct ubifs_info *c = dir->i_sb->s_fs_info;
+ int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
+ struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
+ .dirtied_ino = 1 };
+ struct ubifs_inode *dir_ui = ubifs_inode(dir);
+
+ /*
+ * Budget request settings: new inode, new direntry, changing the
+ * parent directory inode.
+ */
+
+ dbg_gen("dent '%.*s', mode %#x in dir ino %lu",
+ dentry->d_name.len, dentry->d_name.name, mode, dir->i_ino);
+
+ err = ubifs_budget_space(c, &req);
+ if (err)
+ return err;
+
+ inode = ubifs_new_inode(c, dir, mode);
+ if (IS_ERR(inode)) {
+ err = PTR_ERR(inode);
+ goto out_budg;
+ }
+
+ mutex_lock(&dir_ui->ui_mutex);
+ dir->i_size += sz_change;
+ dir_ui->ui_size = dir->i_size;
+ dir->i_mtime = dir->i_ctime = inode->i_ctime;
+ err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
+ if (err)
+ goto out_cancel;
+ mutex_unlock(&dir_ui->ui_mutex);
+
+ ubifs_release_budget(c, &req);
+ insert_inode_hash(inode);
+ d_instantiate(dentry, inode);
+ return 0;
+
+out_cancel:
+ dir->i_size -= sz_change;
+ dir_ui->ui_size = dir->i_size;
+ mutex_unlock(&dir_ui->ui_mutex);
+ make_bad_inode(inode);
+ iput(inode);
+out_budg:
+ ubifs_release_budget(c, &req);
+ ubifs_err("cannot create regular file, error %d", err);
+ return err;
+}
+
+/**
+ * vfs_dent_type - get VFS directory entry type.
+ * @type: UBIFS directory entry type
+ *
+ * This function converts UBIFS directory entry type into VFS directory entry
+ * type.
+ */
+static unsigned int vfs_dent_type(uint8_t type)
+{
+ switch (type) {
+ case UBIFS_ITYPE_REG:
+ return DT_REG;
+ case UBIFS_ITYPE_DIR:
+ return DT_DIR;
+ case UBIFS_ITYPE_LNK:
+ return DT_LNK;
+ case UBIFS_ITYPE_BLK:
+ return DT_BLK;
+ case UBIFS_ITYPE_CHR:
+ return DT_CHR;
+ case UBIFS_ITYPE_FIFO:
+ return DT_FIFO;
+ case UBIFS_ITYPE_SOCK:
+ return DT_SOCK;
+ default:
+ BUG();
+ }
+ return 0;
+}
+
+/*
+ * The classical Unix view for directory is that it is a linear array of
+ * (name, inode number) entries. Linux/VFS assumes this model as well.
+ * Particularly, 'readdir()' call wants us to return a directory entry offset
+ * which later may be used to continue 'readdir()'ing the directory or to
+ * 'seek()' to that specific direntry. Obviously UBIFS does not really fit this
+ * model because directory entries are identified by keys, which may collide.
+ *
+ * UBIFS uses directory entry hash value for directory offsets, so
+ * 'seekdir()'/'telldir()' may not always work because of possible key
+ * collisions. But UBIFS guarantees that consecutive 'readdir()' calls work
+ * properly by means of saving full directory entry name in the private field
+ * of the file description object.
+ *
+ * This means that UBIFS cannot support NFS which requires full
+ * 'seekdir()'/'telldir()' support.
+ */
+static int ubifs_readdir(struct file *file, void *dirent, filldir_t filldir)
+{
+ int err, over = 0;
+ struct qstr nm;
+ union ubifs_key key;
+ struct ubifs_dent_node *dent;
+ struct inode *dir = file->f_path.dentry->d_inode;
+ struct ubifs_info *c = dir->i_sb->s_fs_info;
+
+ dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, file->f_pos);
+
+ if (file->f_pos > UBIFS_S_KEY_HASH_MASK || file->f_pos == 2)
+ /*
+ * The directory was seek'ed to a senseless position or there
+ * are no more entries.
+ */
+ return 0;
+
+ /* File positions 0 and 1 correspond to "." and ".." */
+ if (file->f_pos == 0) {
+ ubifs_assert(!file->private_data);
+ over = filldir(dirent, ".", 1, 0, dir->i_ino, DT_DIR);
+ if (over)
+ return 0;
+ file->f_pos = 1;
+ }
+
+ if (file->f_pos == 1) {
+ ubifs_assert(!file->private_data);
+ over = filldir(dirent, "..", 2, 1,
+ parent_ino(file->f_path.dentry), DT_DIR);
+ if (over)
+ return 0;
+
+ /* Find the first entry in TNC and save it */
+ lowest_dent_key(c, &key, dir->i_ino);
+ nm.name = NULL;
+ dent = ubifs_tnc_next_ent(c, &key, &nm);
+ if (IS_ERR(dent)) {
+ err = PTR_ERR(dent);
+ goto out;
+ }
+
+ file->f_pos = key_hash_flash(c, &dent->key);
+ file->private_data = dent;
+ }
+
+ dent = file->private_data;
+ if (!dent) {
+ /*
+ * The directory was seek'ed to and is now readdir'ed.
+ * Find the entry corresponding to @file->f_pos or the
+ * closest one.
+ */
+ dent_key_init_hash(c, &key, dir->i_ino, file->f_pos);
+ nm.name = NULL;
+ dent = ubifs_tnc_next_ent(c, &key, &nm);
+ if (IS_ERR(dent)) {
+ err = PTR_ERR(dent);
+ goto out;
+ }
+ file->f_pos = key_hash_flash(c, &dent->key);
+ file->private_data = dent;
+ }
+
+ while (1) {
+ dbg_gen("feed '%s', ino %llu, new f_pos %#x",
+ dent->name, le64_to_cpu(dent->inum),
+ key_hash_flash(c, &dent->key));
+ ubifs_assert(dent->ch.sqnum > ubifs_inode(dir)->creat_sqnum);
+
+ nm.len = le16_to_cpu(dent->nlen);
+ over = filldir(dirent, dent->name, nm.len, file->f_pos,
+ le64_to_cpu(dent->inum),
+ vfs_dent_type(dent->type));
+ if (over)
+ return 0;
+
+ /* Switch to the next entry */
+ key_read(c, &dent->key, &key);
+ nm.name = dent->name;
+ dent = ubifs_tnc_next_ent(c, &key, &nm);
+ if (IS_ERR(dent)) {
+ err = PTR_ERR(dent);
+ goto out;
+ }
+
+ kfree(file->private_data);
+ file->f_pos = key_hash_flash(c, &dent->key);
+ file->private_data = dent;
+ cond_resched();
+ }
+
+out:
+ if (err != -ENOENT) {
+ ubifs_err("cannot find next direntry, error %d", err);
+ return err;
+ }
+
+ kfree(file->private_data);
+ file->private_data = NULL;
+ file->f_pos = 2;
+ return 0;
+}
+
+/* If a directory is seeked, we have to free saved readdir() state */
+static loff_t ubifs_dir_llseek(struct file *file, loff_t offset, int origin)
+{
+ kfree(file->private_data);
+ file->private_data = NULL;
+ return generic_file_llseek(file, offset, origin);
+}
+
+/* Free saved readdir() state when the directory is closed */
+static int ubifs_dir_release(struct inode *dir, struct file *file)
+{
+ kfree(file->private_data);
+ file->private_data = NULL;
+ return 0;
+}
+
+/**
+ * lock_2_inodes - lock two UBIFS inodes.
+ * @inode1: first inode
+ * @inode2: second inode
+ */
+static void lock_2_inodes(struct inode *inode1, struct inode *inode2)
+{
+ if (inode1->i_ino < inode2->i_ino) {
+ mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_2);
+ mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_3);
+ } else {
+ mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
+ mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_3);
+ }
+}
+
+/**
+ * unlock_2_inodes - unlock two UBIFS inodes inodes.
+ * @inode1: first inode
+ * @inode2: second inode
+ */
+static void unlock_2_inodes(struct inode *inode1, struct inode *inode2)
+{
+ mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
+ mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
+}
+
+static int ubifs_link(struct dentry *old_dentry, struct inode *dir,
+ struct dentry *dentry)
+{
+ struct ubifs_info *c = dir->i_sb->s_fs_info;
+ struct inode *inode = old_dentry->d_inode;
+ struct ubifs_inode *ui = ubifs_inode(inode);
+ struct ubifs_inode *dir_ui = ubifs_inode(dir);
+ int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
+ struct ubifs_budget_req req = { .new_dent = 1, .dirtied_ino = 2,
+ .dirtied_ino_d = ui->data_len };
+
+ /*
+ * Budget request settings: new direntry, changing the target inode,
+ * changing the parent inode.
+ */
+
+ dbg_gen("dent '%.*s' to ino %lu (nlink %d) in dir ino %lu",
+ dentry->d_name.len, dentry->d_name.name, inode->i_ino,
+ inode->i_nlink, dir->i_ino);
+ err = dbg_check_synced_i_size(inode);
+ if (err)
+ return err;
+
+ err = ubifs_budget_space(c, &req);
+ if (err)
+ return err;
+
+ lock_2_inodes(dir, inode);
+ inc_nlink(inode);
+ atomic_inc(&inode->i_count);
+ inode->i_ctime = ubifs_current_time(inode);
+ dir->i_size += sz_change;
+ dir_ui->ui_size = dir->i_size;
+ dir->i_mtime = dir->i_ctime = inode->i_ctime;
+ err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
+ if (err)
+ goto out_cancel;
+ unlock_2_inodes(dir, inode);
+
+ ubifs_release_budget(c, &req);
+ d_instantiate(dentry, inode);
+ return 0;
+
+out_cancel:
+ dir->i_size -= sz_change;
+ dir_ui->ui_size = dir->i_size;
+ drop_nlink(inode);
+ unlock_2_inodes(dir, inode);
+ ubifs_release_budget(c, &req);
+ iput(inode);
+ return err;
+}
+
+static int ubifs_unlink(struct inode *dir, struct dentry *dentry)
+{
+ struct ubifs_info *c = dir->i_sb->s_fs_info;
+ struct inode *inode = dentry->d_inode;
+ struct ubifs_inode *dir_ui = ubifs_inode(dir);
+ int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
+ int err, budgeted = 1;
+ struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
+
+ /*
+ * Budget request settings: deletion direntry, deletion inode (+1 for
+ * @dirtied_ino), changing the parent directory inode. If budgeting
+ * fails, go ahead anyway because we have extra space reserved for
+ * deletions.
+ */
+
+ dbg_gen("dent '%.*s' from ino %lu (nlink %d) in dir ino %lu",
+ dentry->d_name.len, dentry->d_name.name, inode->i_ino,
+ inode->i_nlink, dir->i_ino);
+ err = dbg_check_synced_i_size(inode);
+ if (err)
+ return err;
+
+ err = ubifs_budget_space(c, &req);
+ if (err) {
+ if (err != -ENOSPC)
+ return err;
+ err = 0;
+ budgeted = 0;
+ }
+
+ lock_2_inodes(dir, inode);
+ inode->i_ctime = ubifs_current_time(dir);
+ drop_nlink(inode);
+ dir->i_size -= sz_change;
+ dir_ui->ui_size = dir->i_size;
+ dir->i_mtime = dir->i_ctime = inode->i_ctime;
+ err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
+ if (err)
+ goto out_cancel;
+ unlock_2_inodes(dir, inode);
+
+ if (budgeted)
+ ubifs_release_budget(c, &req);
+ else {
+ /* We've deleted something - clean the "no space" flags */
+ c->nospace = c->nospace_rp = 0;
+ smp_wmb();
+ }
+ return 0;
+
+out_cancel:
+ dir->i_size += sz_change;
+ dir_ui->ui_size = dir->i_size;
+ inc_nlink(inode);
+ unlock_2_inodes(dir, inode);
+ if (budgeted)
+ ubifs_release_budget(c, &req);
+ return err;
+}
+
+/**
+ * check_dir_empty - check if a directory is empty or not.
+ * @c: UBIFS file-system description object
+ * @dir: VFS inode object of the directory to check
+ *
+ * This function checks if directory @dir is empty. Returns zero if the
+ * directory is empty, %-ENOTEMPTY if it is not, and other negative error codes
+ * in case of of errors.
+ */
+static int check_dir_empty(struct ubifs_info *c, struct inode *dir)
+{
+ struct qstr nm = { .name = NULL };
+ struct ubifs_dent_node *dent;
+ union ubifs_key key;
+ int err;
+
+ lowest_dent_key(c, &key, dir->i_ino);
+ dent = ubifs_tnc_next_ent(c, &key, &nm);
+ if (IS_ERR(dent)) {
+ err = PTR_ERR(dent);
+ if (err == -ENOENT)
+ err = 0;
+ } else {
+ kfree(dent);
+ err = -ENOTEMPTY;
+ }
+ return err;
+}
+
+static int ubifs_rmdir(struct inode *dir, struct dentry *dentry)
+{
+ struct ubifs_info *c = dir->i_sb->s_fs_info;
+ struct inode *inode = dentry->d_inode;
+ int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
+ int err, budgeted = 1;
+ struct ubifs_inode *dir_ui = ubifs_inode(dir);
+ struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
+
+ /*
+ * Budget request settings: deletion direntry, deletion inode and
+ * changing the parent inode. If budgeting fails, go ahead anyway
+ * because we have extra space reserved for deletions.
+ */
+
+ dbg_gen("directory '%.*s', ino %lu in dir ino %lu", dentry->d_name.len,
+ dentry->d_name.name, inode->i_ino, dir->i_ino);
+
+ err = check_dir_empty(c, dentry->d_inode);
+ if (err)
+ return err;
+
+ err = ubifs_budget_space(c, &req);
+ if (err) {
+ if (err != -ENOSPC)
+ return err;
+ budgeted = 0;
+ }
+
+ lock_2_inodes(dir, inode);
+ inode->i_ctime = ubifs_current_time(dir);
+ clear_nlink(inode);
+ drop_nlink(dir);
+ dir->i_size -= sz_change;
+ dir_ui->ui_size = dir->i_size;
+ dir->i_mtime = dir->i_ctime = inode->i_ctime;
+ err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
+ if (err)
+ goto out_cancel;
+ unlock_2_inodes(dir, inode);
+
+ if (budgeted)
+ ubifs_release_budget(c, &req);
+ else {
+ /* We've deleted something - clean the "no space" flags */
+ c->nospace = c->nospace_rp = 0;
+ smp_wmb();
+ }
+ return 0;
+
+out_cancel:
+ dir->i_size += sz_change;
+ dir_ui->ui_size = dir->i_size;
+ inc_nlink(dir);
+ inc_nlink(inode);
+ inc_nlink(inode);
+ unlock_2_inodes(dir, inode);
+ if (budgeted)
+ ubifs_release_budget(c, &req);
+ return err;
+}
+
+static int ubifs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
+{
+ struct inode *inode;
+ struct ubifs_inode *dir_ui = ubifs_inode(dir);
+ struct ubifs_info *c = dir->i_sb->s_fs_info;
+ int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
+ struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
+ .dirtied_ino_d = 1 };
+
+ /*
+ * Budget request settings: new inode, new direntry and changing parent
+ * directory inode.
+ */
+
+ dbg_gen("dent '%.*s', mode %#x in dir ino %lu",
+ dentry->d_name.len, dentry->d_name.name, mode, dir->i_ino);
+
+ err = ubifs_budget_space(c, &req);
+ if (err)
+ return err;
+
+ inode = ubifs_new_inode(c, dir, S_IFDIR | mode);
+ if (IS_ERR(inode)) {
+ err = PTR_ERR(inode);
+ goto out_budg;
+ }
+
+ mutex_lock(&dir_ui->ui_mutex);
+ insert_inode_hash(inode);
+ inc_nlink(inode);
+ inc_nlink(dir);
+ dir->i_size += sz_change;
+ dir_ui->ui_size = dir->i_size;
+ dir->i_mtime = dir->i_ctime = inode->i_ctime;
+ err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
+ if (err) {
+ ubifs_err("cannot create directory, error %d", err);
+ goto out_cancel;
+ }
+ mutex_unlock(&dir_ui->ui_mutex);
+
+ ubifs_release_budget(c, &req);
+ d_instantiate(dentry, inode);
+ return 0;
+
+out_cancel:
+ dir->i_size -= sz_change;
+ dir_ui->ui_size = dir->i_size;
+ drop_nlink(dir);
+ mutex_unlock(&dir_ui->ui_mutex);
+ make_bad_inode(inode);
+ iput(inode);
+out_budg:
+ ubifs_release_budget(c, &req);
+ return err;
+}
+
+static int ubifs_mknod(struct inode *dir, struct dentry *dentry,
+ int mode, dev_t rdev)
+{
+ struct inode *inode;
+ struct ubifs_inode *ui;
+ struct ubifs_inode *dir_ui = ubifs_inode(dir);
+ struct ubifs_info *c = dir->i_sb->s_fs_info;
+ union ubifs_dev_desc *dev = NULL;
+ int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
+ int err, devlen = 0;
+ struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
+ .new_ino_d = devlen, .dirtied_ino = 1 };
+
+ /*
+ * Budget request settings: new inode, new direntry and changing parent
+ * directory inode.
+ */
+
+ dbg_gen("dent '%.*s' in dir ino %lu",
+ dentry->d_name.len, dentry->d_name.name, dir->i_ino);
+
+ if (!new_valid_dev(rdev))
+ return -EINVAL;
+
+ if (S_ISBLK(mode) || S_ISCHR(mode)) {
+ dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
+ if (!dev)
+ return -ENOMEM;
+ devlen = ubifs_encode_dev(dev, rdev);
+ }
+
+ err = ubifs_budget_space(c, &req);
+ if (err) {
+ kfree(dev);
+ return err;
+ }
+
+ inode = ubifs_new_inode(c, dir, mode);
+ if (IS_ERR(inode)) {
+ kfree(dev);
+ err = PTR_ERR(inode);
+ goto out_budg;
+ }
+
+ init_special_inode(inode, inode->i_mode, rdev);
+ inode->i_size = ubifs_inode(inode)->ui_size = devlen;
+ ui = ubifs_inode(inode);
+ ui->data = dev;
+ ui->data_len = devlen;
+
+ mutex_lock(&dir_ui->ui_mutex);
+ dir->i_size += sz_change;
+ dir_ui->ui_size = dir->i_size;
+ dir->i_mtime = dir->i_ctime = inode->i_ctime;
+ err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
+ if (err)
+ goto out_cancel;
+ mutex_unlock(&dir_ui->ui_mutex);
+
+ ubifs_release_budget(c, &req);
+ insert_inode_hash(inode);
+ d_instantiate(dentry, inode);
+ return 0;
+
+out_cancel:
+ dir->i_size -= sz_change;
+ dir_ui->ui_size = dir->i_size;
+ mutex_unlock(&dir_ui->ui_mutex);
+ make_bad_inode(inode);
+ iput(inode);
+out_budg:
+ ubifs_release_budget(c, &req);
+ return err;
+}
+
+static int ubifs_symlink(struct inode *dir, struct dentry *dentry,
+ const char *symname)
+{
+ struct inode *inode;
+ struct ubifs_inode *ui;
+ struct ubifs_inode *dir_ui = ubifs_inode(dir);
+ struct ubifs_info *c = dir->i_sb->s_fs_info;
+ int err, len = strlen(symname);
+ int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
+ struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
+ .new_ino_d = len, .dirtied_ino = 1 };
+
+ /*
+ * Budget request settings: new inode, new direntry and changing parent
+ * directory inode.
+ */
+
+ dbg_gen("dent '%.*s', target '%s' in dir ino %lu", dentry->d_name.len,
+ dentry->d_name.name, symname, dir->i_ino);
+
+ if (len > UBIFS_MAX_INO_DATA)
+ return -ENAMETOOLONG;
+
+ err = ubifs_budget_space(c, &req);
+ if (err)
+ return err;
+
+ inode = ubifs_new_inode(c, dir, S_IFLNK | S_IRWXUGO);
+ if (IS_ERR(inode)) {
+ err = PTR_ERR(inode);
+ goto out_budg;
+ }
+
+ ui = ubifs_inode(inode);
+ ui->data = kmalloc(len + 1, GFP_NOFS);
+ if (!ui->data) {
+ err = -ENOMEM;
+ goto out_inode;
+ }
+
+ memcpy(ui->data, symname, len);
+ ((char *)ui->data)[len] = '\0';
+ /*
+ * The terminating zero byte is not written to the flash media and it
+ * is put just to make later in-memory string processing simpler. Thus,
+ * data length is @len, not @len + %1.
+ */
+ ui->data_len = len;
+ inode->i_size = ubifs_inode(inode)->ui_size = len;
+
+ mutex_lock(&dir_ui->ui_mutex);
+ dir->i_size += sz_change;
+ dir_ui->ui_size = dir->i_size;
+ dir->i_mtime = dir->i_ctime = inode->i_ctime;
+ err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
+ if (err)
+ goto out_cancel;
+ mutex_unlock(&dir_ui->ui_mutex);
+
+ ubifs_release_budget(c, &req);
+ insert_inode_hash(inode);
+ d_instantiate(dentry, inode);
+ return 0;
+
+out_cancel:
+ dir->i_size -= sz_change;
+ dir_ui->ui_size = dir->i_size;
+ mutex_unlock(&dir_ui->ui_mutex);
+out_inode:
+ make_bad_inode(inode);
+ iput(inode);
+out_budg:
+ ubifs_release_budget(c, &req);
+ return err;
+}
+
+/**
+ * lock_3_inodes - lock three UBIFS inodes for rename.
+ * @inode1: first inode
+ * @inode2: second inode
+ * @inode3: third inode
+ *
+ * For 'ubifs_rename()', @inode1 may be the same as @inode2 whereas @inode3 may
+ * be null.
+ */
+static void lock_3_inodes(struct inode *inode1, struct inode *inode2,
+ struct inode *inode3)
+{
+ struct inode *i1, *i2, *i3;
+
+ if (!inode3) {
+ if (inode1 != inode2) {
+ lock_2_inodes(inode1, inode2);
+ return;
+ }
+ mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
+ return;
+ }
+
+ if (inode1 == inode2) {
+ lock_2_inodes(inode1, inode3);
+ return;
+ }
+
+ /* 3 different inodes */
+ if (inode1 < inode2) {
+ i3 = inode2;
+ if (inode1 < inode3) {
+ i1 = inode1;
+ i2 = inode3;
+ } else {
+ i1 = inode3;
+ i2 = inode1;
+ }
+ } else {
+ i3 = inode1;
+ if (inode2 < inode3) {
+ i1 = inode2;
+ i2 = inode3;
+ } else {
+ i1 = inode3;
+ i2 = inode2;
+ }
+ }
+ mutex_lock_nested(&ubifs_inode(i1)->ui_mutex, WB_MUTEX_1);
+ lock_2_inodes(i2, i3);
+}
+
+/**
+ * unlock_3_inodes - unlock three UBIFS inodes for rename.
+ * @inode1: first inode
+ * @inode2: second inode
+ * @inode3: third inode
+ */
+static void unlock_3_inodes(struct inode *inode1, struct inode *inode2,
+ struct inode *inode3)
+{
+ mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
+ if (inode1 != inode2)
+ mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
+ if (inode3)
+ mutex_unlock(&ubifs_inode(inode3)->ui_mutex);
+}
+
+static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry)
+{
+ struct ubifs_info *c = old_dir->i_sb->s_fs_info;
+ struct inode *old_inode = old_dentry->d_inode;
+ struct inode *new_inode = new_dentry->d_inode;
+ struct ubifs_inode *old_inode_ui = ubifs_inode(old_inode);
+ int err, release, sync = 0, move = (new_dir != old_dir);
+ int is_dir = S_ISDIR(old_inode->i_mode);
+ int unlink = !!new_inode;
+ int new_sz = CALC_DENT_SIZE(new_dentry->d_name.len);
+ int old_sz = CALC_DENT_SIZE(old_dentry->d_name.len);
+ struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
+ .dirtied_ino = 3 };
+ struct ubifs_budget_req ino_req = { .dirtied_ino = 1,
+ .dirtied_ino_d = old_inode_ui->data_len };
+ struct timespec time;
+
+ /*
+ * Budget request settings: deletion direntry, new direntry, removing
+ * the old inode, and changing old and new parent directory inodes.
+ *
+ * However, this operation also marks the target inode as dirty and
+ * does not write it, so we allocate budget for the target inode
+ * separately.
+ */
+
+ dbg_gen("dent '%.*s' ino %lu in dir ino %lu to dent '%.*s' in "
+ "dir ino %lu", old_dentry->d_name.len, old_dentry->d_name.name,
+ old_inode->i_ino, old_dir->i_ino, new_dentry->d_name.len,
+ new_dentry->d_name.name, new_dir->i_ino);
+
+ if (unlink && is_dir) {
+ err = check_dir_empty(c, new_inode);
+ if (err)
+ return err;
+ }
+
+ err = ubifs_budget_space(c, &req);
+ if (err)
+ return err;
+ err = ubifs_budget_space(c, &ino_req);
+ if (err) {
+ ubifs_release_budget(c, &req);
+ return err;
+ }
+
+ lock_3_inodes(old_dir, new_dir, new_inode);
+
+ /*
+ * Like most other Unix systems, set the @i_ctime for inodes on a
+ * rename.
+ */
+ time = ubifs_current_time(old_dir);
+ old_inode->i_ctime = time;
+
+ /* We must adjust parent link count when renaming directories */
+ if (is_dir) {
+ if (move) {
+ /*
+ * @old_dir loses a link because we are moving
+ * @old_inode to a different directory.
+ */
+ drop_nlink(old_dir);
+ /*
+ * @new_dir only gains a link if we are not also
+ * overwriting an existing directory.
+ */
+ if (!unlink)
+ inc_nlink(new_dir);
+ } else {
+ /*
+ * @old_inode is not moving to a different directory,
+ * but @old_dir still loses a link if we are
+ * overwriting an existing directory.
+ */
+ if (unlink)
+ drop_nlink(old_dir);
+ }
+ }
+
+ old_dir->i_size -= old_sz;
+ ubifs_inode(old_dir)->ui_size = old_dir->i_size;
+ old_dir->i_mtime = old_dir->i_ctime = time;
+ new_dir->i_mtime = new_dir->i_ctime = time;
+
+ /*
+ * And finally, if we unlinked a direntry which happened to have the
+ * same name as the moved direntry, we have to decrement @i_nlink of
+ * the unlinked inode and change its ctime.
+ */
+ if (unlink) {
+ /*
+ * Directories cannot have hard-links, so if this is a
+ * directory, decrement its @i_nlink twice because an empty
+ * directory has @i_nlink 2.
+ */
+ if (is_dir)
+ drop_nlink(new_inode);
+ new_inode->i_ctime = time;
+ drop_nlink(new_inode);
+ } else {
+ new_dir->i_size += new_sz;
+ ubifs_inode(new_dir)->ui_size = new_dir->i_size;
+ }
+
+ /*
+ * Do not ask 'ubifs_jnl_rename()' to flush write-buffer if @old_inode
+ * is dirty, because this will be done later on at the end of
+ * 'ubifs_rename()'.
+ */
+ if (IS_SYNC(old_inode)) {
+ sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
+ if (unlink && IS_SYNC(new_inode))
+ sync = 1;
+ }
+ err = ubifs_jnl_rename(c, old_dir, old_dentry, new_dir, new_dentry,
+ sync);
+ if (err)
+ goto out_cancel;
+
+ unlock_3_inodes(old_dir, new_dir, new_inode);
+ ubifs_release_budget(c, &req);
+
+ mutex_lock(&old_inode_ui->ui_mutex);
+ release = old_inode_ui->dirty;
+ mark_inode_dirty_sync(old_inode);
+ mutex_unlock(&old_inode_ui->ui_mutex);
+
+ if (release)
+ ubifs_release_budget(c, &ino_req);
+ if (IS_SYNC(old_inode))
+ err = old_inode->i_sb->s_op->write_inode(old_inode, 1);
+ return err;
+
+out_cancel:
+ if (unlink) {
+ if (is_dir)
+ inc_nlink(new_inode);
+ inc_nlink(new_inode);
+ } else {
+ new_dir->i_size -= new_sz;
+ ubifs_inode(new_dir)->ui_size = new_dir->i_size;
+ }
+ old_dir->i_size += old_sz;
+ ubifs_inode(old_dir)->ui_size = old_dir->i_size;
+ if (is_dir) {
+ if (move) {
+ inc_nlink(old_dir);
+ if (!unlink)
+ drop_nlink(new_dir);
+ } else {
+ if (unlink)
+ inc_nlink(old_dir);
+ }
+ }
+ unlock_3_inodes(old_dir, new_dir, new_inode);
+ ubifs_release_budget(c, &ino_req);
+ ubifs_release_budget(c, &req);
+ return err;
+}
+
+int ubifs_getattr(struct vfsmount *mnt, struct dentry *dentry,
+ struct kstat *stat)
+{
+ loff_t size;
+ struct inode *inode = dentry->d_inode;
+ struct ubifs_inode *ui = ubifs_inode(inode);
+
+ mutex_lock(&ui->ui_mutex);
+ stat->dev = inode->i_sb->s_dev;
+ stat->ino = inode->i_ino;
+ stat->mode = inode->i_mode;
+ stat->nlink = inode->i_nlink;
+ stat->uid = inode->i_uid;
+ stat->gid = inode->i_gid;
+ stat->rdev = inode->i_rdev;
+ stat->atime = inode->i_atime;
+ stat->mtime = inode->i_mtime;
+ stat->ctime = inode->i_ctime;
+ stat->blksize = UBIFS_BLOCK_SIZE;
+ stat->size = ui->ui_size;
+
+ /*
+ * Unfortunately, the 'stat()' system call was designed for block
+ * device based file systems, and it is not appropriate for UBIFS,
+ * because UBIFS does not have notion of "block". For example, it is
+ * difficult to tell how many block a directory takes - it actually
+ * takes less than 300 bytes, but we have to round it to block size,
+ * which introduces large mistake. This makes utilities like 'du' to
+ * report completely senseless numbers. This is the reason why UBIFS
+ * goes the same way as JFFS2 - it reports zero blocks for everything
+ * but regular files, which makes more sense than reporting completely
+ * wrong sizes.
+ */
+ if (S_ISREG(inode->i_mode)) {
+ size = ui->xattr_size;
+ size += stat->size;
+ size = ALIGN(size, UBIFS_BLOCK_SIZE);
+ /*
+ * Note, user-space expects 512-byte blocks count irrespectively
+ * of what was reported in @stat->size.
+ */
+ stat->blocks = size >> 9;
+ } else
+ stat->blocks = 0;
+ mutex_unlock(&ui->ui_mutex);
+ return 0;
+}
+
+struct inode_operations ubifs_dir_inode_operations = {
+ .lookup = ubifs_lookup,
+ .create = ubifs_create,
+ .link = ubifs_link,
+ .symlink = ubifs_symlink,
+ .unlink = ubifs_unlink,
+ .mkdir = ubifs_mkdir,
+ .rmdir = ubifs_rmdir,
+ .mknod = ubifs_mknod,
+ .rename = ubifs_rename,
+ .setattr = ubifs_setattr,
+ .getattr = ubifs_getattr,
+#ifdef CONFIG_UBIFS_FS_XATTR
+ .setxattr = ubifs_setxattr,
+ .getxattr = ubifs_getxattr,
+ .listxattr = ubifs_listxattr,
+ .removexattr = ubifs_removexattr,
+#endif
+};
+
+struct file_operations ubifs_dir_operations = {
+ .llseek = ubifs_dir_llseek,
+ .release = ubifs_dir_release,
+ .read = generic_read_dir,
+ .readdir = ubifs_readdir,
+ .fsync = ubifs_fsync,
+ .unlocked_ioctl = ubifs_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = ubifs_compat_ioctl,
+#endif
+};
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ * Adrian Hunter
+ */
+
+/*
+ * This file implements VFS file and inode operations of regular files, device
+ * nodes and symlinks as well as address space operations.
+ *
+ * UBIFS uses 2 page flags: PG_private and PG_checked. PG_private is set if the
+ * page is dirty and is used for budgeting purposes - dirty pages should not be
+ * budgeted. The PG_checked flag is set if full budgeting is required for the
+ * page e.g., when it corresponds to a file hole or it is just beyond the file
+ * size. The budgeting is done in 'ubifs_write_begin()', because it is OK to
+ * fail in this function, and the budget is released in 'ubifs_write_end()'. So
+ * the PG_private and PG_checked flags carry the information about how the page
+ * was budgeted, to make it possible to release the budget properly.
+ *
+ * A thing to keep in mind: inode's 'i_mutex' is locked in most VFS operations
+ * we implement. However, this is not true for '->writepage()', which might be
+ * called with 'i_mutex' unlocked. For example, when pdflush is performing
+ * write-back, it calls 'writepage()' with unlocked 'i_mutex', although the
+ * inode has 'I_LOCK' flag in this case. At "normal" work-paths 'i_mutex' is
+ * locked in '->writepage', e.g. in "sys_write -> alloc_pages -> direct reclaim
+ * path'. So, in '->writepage()' we are only guaranteed that the page is
+ * locked.
+ *
+ * Similarly, 'i_mutex' does not have to be locked in readpage(), e.g.,
+ * readahead path does not have it locked ("sys_read -> generic_file_aio_read
+ * -> ondemand_readahead -> readpage"). In case of readahead, 'I_LOCK' flag is
+ * not set as well. However, UBIFS disables readahead.
+ *
+ * This, for example means that there might be 2 concurrent '->writepage()'
+ * calls for the same inode, but different inode dirty pages.
+ */
+
+#include "ubifs.h"
+#include <linux/mount.h>
+
+static int read_block(struct inode *inode, void *addr, unsigned int block,
+ struct ubifs_data_node *dn)
+{
+ struct ubifs_info *c = inode->i_sb->s_fs_info;
+ int err, len, out_len;
+ union ubifs_key key;
+ unsigned int dlen;
+
+ data_key_init(c, &key, inode->i_ino, block);
+ err = ubifs_tnc_lookup(c, &key, dn);
+ if (err) {
+ if (err == -ENOENT)
+ /* Not found, so it must be a hole */
+ memset(addr, 0, UBIFS_BLOCK_SIZE);
+ return err;
+ }
+
+ ubifs_assert(dn->ch.sqnum > ubifs_inode(inode)->creat_sqnum);
+
+ len = le32_to_cpu(dn->size);
+ if (len <= 0 || len > UBIFS_BLOCK_SIZE)
+ goto dump;
+
+ dlen = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ;
+ out_len = UBIFS_BLOCK_SIZE;
+ err = ubifs_decompress(&dn->data, dlen, addr, &out_len,
+ le16_to_cpu(dn->compr_type));
+ if (err || len != out_len)
+ goto dump;
+
+ /*
+ * Data length can be less than a full block, even for blocks that are
+ * not the last in the file (e.g., as a result of making a hole and
+ * appending data). Ensure that the remainder is zeroed out.
+ */
+ if (len < UBIFS_BLOCK_SIZE)
+ memset(addr + len, 0, UBIFS_BLOCK_SIZE - len);
+
+ return 0;
+
+dump:
+ ubifs_err("bad data node (block %u, inode %lu)",
+ block, inode->i_ino);
+ dbg_dump_node(c, dn);
+ return -EINVAL;
+}
+
+static int do_readpage(struct page *page)
+{
+ void *addr;
+ int err = 0, i;
+ unsigned int block, beyond;
+ struct ubifs_data_node *dn;
+ struct inode *inode = page->mapping->host;
+ loff_t i_size = i_size_read(inode);
+
+ dbg_gen("ino %lu, pg %lu, i_size %lld, flags %#lx",
+ inode->i_ino, page->index, i_size, page->flags);
+ ubifs_assert(!PageChecked(page));
+ ubifs_assert(!PagePrivate(page));
+
+ addr = kmap(page);
+
+ block = page->index << UBIFS_BLOCKS_PER_PAGE_SHIFT;
+ beyond = (i_size + UBIFS_BLOCK_SIZE - 1) >> UBIFS_BLOCK_SHIFT;
+ if (block >= beyond) {
+ /* Reading beyond inode */
+ SetPageChecked(page);
+ memset(addr, 0, PAGE_CACHE_SIZE);
+ goto out;
+ }
+
+ dn = kmalloc(UBIFS_MAX_DATA_NODE_SZ, GFP_NOFS);
+ if (!dn) {
+ err = -ENOMEM;
+ goto error;
+ }
+
+ i = 0;
+ while (1) {
+ int ret;
+
+ if (block >= beyond) {
+ /* Reading beyond inode */
+ err = -ENOENT;
+ memset(addr, 0, UBIFS_BLOCK_SIZE);
+ } else {
+ ret = read_block(inode, addr, block, dn);
+ if (ret) {
+ err = ret;
+ if (err != -ENOENT)
+ break;
+ }
+ }
+ if (++i >= UBIFS_BLOCKS_PER_PAGE)
+ break;
+ block += 1;
+ addr += UBIFS_BLOCK_SIZE;
+ }
+ if (err) {
+ if (err == -ENOENT) {
+ /* Not found, so it must be a hole */
+ SetPageChecked(page);
+ dbg_gen("hole");
+ goto out_free;
+ }
+ ubifs_err("cannot read page %lu of inode %lu, error %d",
+ page->index, inode->i_ino, err);
+ goto error;
+ }
+
+out_free:
+ kfree(dn);
+out:
+ SetPageUptodate(page);
+ ClearPageError(page);
+ flush_dcache_page(page);
+ kunmap(page);
+ return 0;
+
+error:
+ kfree(dn);
+ ClearPageUptodate(page);
+ SetPageError(page);
+ flush_dcache_page(page);
+ kunmap(page);
+ return err;
+}
+
+/**
+ * release_new_page_budget - release budget of a new page.
+ * @c: UBIFS file-system description object
+ *
+ * This is a helper function which releases budget corresponding to the budget
+ * of one new page of data.
+ */
+static void release_new_page_budget(struct ubifs_info *c)
+{
+ struct ubifs_budget_req req = { .recalculate = 1, .new_page = 1 };
+
+ ubifs_release_budget(c, &req);
+}
+
+/**
+ * release_existing_page_budget - release budget of an existing page.
+ * @c: UBIFS file-system description object
+ *
+ * This is a helper function which releases budget corresponding to the budget
+ * of changing one one page of data which already exists on the flash media.
+ */
+static void release_existing_page_budget(struct ubifs_info *c)
+{
+ struct ubifs_budget_req req = { .dd_growth = c->page_budget};
+
+ ubifs_release_budget(c, &req);
+}
+
+static int write_begin_slow(struct address_space *mapping,
+ loff_t pos, unsigned len, struct page **pagep)
+{
+ struct inode *inode = mapping->host;
+ struct ubifs_info *c = inode->i_sb->s_fs_info;
+ pgoff_t index = pos >> PAGE_CACHE_SHIFT;
+ struct ubifs_budget_req req = { .new_page = 1 };
+ int uninitialized_var(err), appending = !!(pos + len > inode->i_size);
+ struct page *page;
+
+ dbg_gen("ino %lu, pos %llu, len %u, i_size %lld",
+ inode->i_ino, pos, len, inode->i_size);
+
+ /*
+ * At the slow path we have to budget before locking the page, because
+ * budgeting may force write-back, which would wait on locked pages and
+ * deadlock if we had the page locked. At this point we do not know
+ * anything about the page, so assume that this is a new page which is
+ * written to a hole. This corresponds to largest budget. Later the
+ * budget will be amended if this is not true.
+ */
+ if (appending)
+ /* We are appending data, budget for inode change */
+ req.dirtied_ino = 1;
+
+ err = ubifs_budget_space(c, &req);
+ if (unlikely(err))
+ return err;
+
+ page = __grab_cache_page(mapping, index);
+ if (unlikely(!page)) {
+ ubifs_release_budget(c, &req);
+ return -ENOMEM;
+ }
+
+ if (!PageUptodate(page)) {
+ if (!(pos & PAGE_CACHE_MASK) && len == PAGE_CACHE_SIZE)
+ SetPageChecked(page);
+ else {
+ err = do_readpage(page);
+ if (err) {
+ unlock_page(page);
+ page_cache_release(page);
+ return err;
+ }
+ }
+
+ SetPageUptodate(page);
+ ClearPageError(page);
+ }
+
+ if (PagePrivate(page))
+ /*
+ * The page is dirty, which means it was budgeted twice:
+ * o first time the budget was allocated by the task which
+ * made the page dirty and set the PG_private flag;
+ * o and then we budgeted for it for the second time at the
+ * very beginning of this function.
+ *
+ * So what we have to do is to release the page budget we
+ * allocated.
+ */
+ release_new_page_budget(c);
+ else if (!PageChecked(page))
+ /*
+ * We are changing a page which already exists on the media.
+ * This means that changing the page does not make the amount
+ * of indexing information larger, and this part of the budget
+ * which we have already acquired may be released.
+ */
+ ubifs_convert_page_budget(c);
+
+ if (appending) {
+ struct ubifs_inode *ui = ubifs_inode(inode);
+
+ /*
+ * 'ubifs_write_end()' is optimized from the fast-path part of
+ * 'ubifs_write_begin()' and expects the @ui_mutex to be locked
+ * if data is appended.
+ */
+ mutex_lock(&ui->ui_mutex);
+ if (ui->dirty)
+ /*
+ * The inode is dirty already, so we may free the
+ * budget we allocated.
+ */
+ ubifs_release_dirty_inode_budget(c, ui);
+ }
+
+ *pagep = page;
+ return 0;
+}
+
+/**
+ * allocate_budget - allocate budget for 'ubifs_write_begin()'.
+ * @c: UBIFS file-system description object
+ * @page: page to allocate budget for
+ * @ui: UBIFS inode object the page belongs to
+ * @appending: non-zero if the page is appended
+ *
+ * This is a helper function for 'ubifs_write_begin()' which allocates budget
+ * for the operation. The budget is allocated differently depending on whether
+ * this is appending, whether the page is dirty or not, and so on. This
+ * function leaves the @ui->ui_mutex locked in case of appending. Returns zero
+ * in case of success and %-ENOSPC in case of failure.
+ */
+static int allocate_budget(struct ubifs_info *c, struct page *page,
+ struct ubifs_inode *ui, int appending)
+{
+ struct ubifs_budget_req req = { .fast = 1 };
+
+ if (PagePrivate(page)) {
+ if (!appending)
+ /*
+ * The page is dirty and we are not appending, which
+ * means no budget is needed at all.
+ */
+ return 0;
+
+ mutex_lock(&ui->ui_mutex);
+ if (ui->dirty)
+ /*
+ * The page is dirty and we are appending, so the inode
+ * has to be marked as dirty. However, it is already
+ * dirty, so we do not need any budget. We may return,
+ * but @ui->ui_mutex hast to be left locked because we
+ * should prevent write-back from flushing the inode
+ * and freeing the budget. The lock will be released in
+ * 'ubifs_write_end()'.
+ */
+ return 0;
+
+ /*
+ * The page is dirty, we are appending, the inode is clean, so
+ * we need to budget the inode change.
+ */
+ req.dirtied_ino = 1;
+ } else {
+ if (PageChecked(page))
+ /*
+ * The page corresponds to a hole and does not
+ * exist on the media. So changing it makes
+ * make the amount of indexing information
+ * larger, and we have to budget for a new
+ * page.
+ */
+ req.new_page = 1;
+ else
+ /*
+ * Not a hole, the change will not add any new
+ * indexing information, budget for page
+ * change.
+ */
+ req.dirtied_page = 1;
+
+ if (appending) {
+ mutex_lock(&ui->ui_mutex);
+ if (!ui->dirty)
+ /*
+ * The inode is clean but we will have to mark
+ * it as dirty because we are appending. This
+ * needs a budget.
+ */
+ req.dirtied_ino = 1;
+ }
+ }
+
+ return ubifs_budget_space(c, &req);
+}
+
+/*
+ * This function is called when a page of data is going to be written. Since
+ * the page of data will not necessarily go to the flash straight away, UBIFS
+ * has to reserve space on the media for it, which is done by means of
+ * budgeting.
+ *
+ * This is the hot-path of the file-system and we are trying to optimize it as
+ * much as possible. For this reasons it is split on 2 parts - slow and fast.
+ *
+ * There many budgeting cases:
+ * o a new page is appended - we have to budget for a new page and for
+ * changing the inode; however, if the inode is already dirty, there is
+ * no need to budget for it;
+ * o an existing clean page is changed - we have budget for it; if the page
+ * does not exist on the media (a hole), we have to budget for a new
+ * page; otherwise, we may budget for changing an existing page; the
+ * difference between these cases is that changing an existing page does
+ * not introduce anything new to the FS indexing information, so it does
+ * not grow, and smaller budget is acquired in this case;
+ * o an existing dirty page is changed - no need to budget at all, because
+ * the page budget has been acquired by earlier, when the page has been
+ * marked dirty.
+ *
+ * UBIFS budgeting sub-system may force write-back if it thinks there is no
+ * space to reserve. This imposes some locking restrictions and makes it
+ * impossible to take into account the above cases, and makes it impossible to
+ * optimize budgeting.
+ *
+ * The solution for this is that the fast path of 'ubifs_write_begin()' assumes
+ * there is a plenty of flash space and the budget will be acquired quickly,
+ * without forcing write-back. The slow path does not make this assumption.
+ */
+static int ubifs_write_begin(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned flags,
+ struct page **pagep, void **fsdata)
+{
+ struct inode *inode = mapping->host;
+ struct ubifs_info *c = inode->i_sb->s_fs_info;
+ struct ubifs_inode *ui = ubifs_inode(inode);
+ pgoff_t index = pos >> PAGE_CACHE_SHIFT;
+ int uninitialized_var(err), appending = !!(pos + len > inode->i_size);
+ struct page *page;
+
+
+ ubifs_assert(ubifs_inode(inode)->ui_size == inode->i_size);
+
+ if (unlikely(c->ro_media))
+ return -EROFS;
+
+ /* Try out the fast-path part first */
+ page = __grab_cache_page(mapping, index);
+ if (unlikely(!page))
+ return -ENOMEM;
+
+ if (!PageUptodate(page)) {
+ /* The page is not loaded from the flash */
+ if (!(pos & PAGE_CACHE_MASK) && len == PAGE_CACHE_SIZE)
+ /*
+ * We change whole page so no need to load it. But we
+ * have to set the @PG_checked flag to make the further
+ * code the page is new. This might be not true, but it
+ * is better to budget more that to read the page from
+ * the media.
+ */
+ SetPageChecked(page);
+ else {
+ err = do_readpage(page);
+ if (err) {
+ unlock_page(page);
+ page_cache_release(page);
+ return err;
+ }
+ }
+
+ SetPageUptodate(page);
+ ClearPageError(page);
+ }
+
+ err = allocate_budget(c, page, ui, appending);
+ if (unlikely(err)) {
+ ubifs_assert(err == -ENOSPC);
+ /*
+ * Budgeting failed which means it would have to force
+ * write-back but didn't, because we set the @fast flag in the
+ * request. Write-back cannot be done now, while we have the
+ * page locked, because it would deadlock. Unlock and free
+ * everything and fall-back to slow-path.
+ */
+ if (appending) {
+ ubifs_assert(mutex_is_locked(&ui->ui_mutex));
+ mutex_unlock(&ui->ui_mutex);
+ }
+ unlock_page(page);
+ page_cache_release(page);
+
+ return write_begin_slow(mapping, pos, len, pagep);
+ }
+
+ /*
+ * Whee, we aquired budgeting quickly - without involving
+ * garbage-collection, committing or forceing write-back. We return
+ * with @ui->ui_mutex locked if we are appending pages, and unlocked
+ * otherwise. This is an optimization (slightly hacky though).
+ */
+ *pagep = page;
+ return 0;
+
+}
+
+/**
+ * cancel_budget - cancel budget.
+ * @c: UBIFS file-system description object
+ * @page: page to cancel budget for
+ * @ui: UBIFS inode object the page belongs to
+ * @appending: non-zero if the page is appended
+ *
+ * This is a helper function for a page write operation. It unlocks the
+ * @ui->ui_mutex in case of appending.
+ */
+static void cancel_budget(struct ubifs_info *c, struct page *page,
+ struct ubifs_inode *ui, int appending)
+{
+ if (appending) {
+ if (!ui->dirty)
+ ubifs_release_dirty_inode_budget(c, ui);
+ mutex_unlock(&ui->ui_mutex);
+ }
+ if (!PagePrivate(page)) {
+ if (PageChecked(page))
+ release_new_page_budget(c);
+ else
+ release_existing_page_budget(c);
+ }
+}
+
+static int ubifs_write_end(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned copied,
+ struct page *page, void *fsdata)
+{
+ struct inode *inode = mapping->host;
+ struct ubifs_inode *ui = ubifs_inode(inode);
+ struct ubifs_info *c = inode->i_sb->s_fs_info;
+ loff_t end_pos = pos + len;
+ int appending = !!(end_pos > inode->i_size);
+
+ dbg_gen("ino %lu, pos %llu, pg %lu, len %u, copied %d, i_size %lld",
+ inode->i_ino, pos, page->index, len, copied, inode->i_size);
+
+ if (unlikely(copied < len && len == PAGE_CACHE_SIZE)) {
+ /*
+ * VFS copied less data to the page that it intended and
+ * declared in its '->write_begin()' call via the @len
+ * argument. If the page was not up-to-date, and @len was
+ * @PAGE_CACHE_SIZE, the 'ubifs_write_begin()' function did
+ * not load it from the media (for optimization reasons). This
+ * means that part of the page contains garbage. So read the
+ * page now.
+ */
+ dbg_gen("copied %d instead of %d, read page and repeat",
+ copied, len);
+ cancel_budget(c, page, ui, appending);
+
+ /*
+ * Return 0 to force VFS to repeat the whole operation, or the
+ * error code if 'do_readpage()' failes.
+ */
+ copied = do_readpage(page);
+ goto out;
+ }
+
+ if (!PagePrivate(page)) {
+ SetPagePrivate(page);
+ atomic_long_inc(&c->dirty_pg_cnt);
+ __set_page_dirty_nobuffers(page);
+ }
+
+ if (appending) {
+ i_size_write(inode, end_pos);
+ ui->ui_size = end_pos;
+ /*
+ * Note, we do not set @I_DIRTY_PAGES (which means that the
+ * inode has dirty pages), this has been done in
+ * '__set_page_dirty_nobuffers()'.
+ */
+ __mark_inode_dirty(inode, I_DIRTY_DATASYNC);
+ ubifs_assert(mutex_is_locked(&ui->ui_mutex));
+ mutex_unlock(&ui->ui_mutex);
+ }
+
+out:
+ unlock_page(page);
+ page_cache_release(page);
+ return copied;
+}
+
+static int ubifs_readpage(struct file *file, struct page *page)
+{
+ do_readpage(page);
+ unlock_page(page);
+ return 0;
+}
+
+static int do_writepage(struct page *page, int len)
+{
+ int err = 0, i, blen;
+ unsigned int block;
+ void *addr;
+ union ubifs_key key;
+ struct inode *inode = page->mapping->host;
+ struct ubifs_info *c = inode->i_sb->s_fs_info;
+
+#ifdef UBIFS_DEBUG
+ spin_lock(&ui->ui_lock);
+ ubifs_assert(page->index <= ui->synced_i_size << PAGE_CACHE_SIZE);
+ spin_unlock(&ui->ui_lock);
+#endif
+
+ /* Update radix tree tags */
+ set_page_writeback(page);
+
+ addr = kmap(page);
+ block = page->index << UBIFS_BLOCKS_PER_PAGE_SHIFT;
+ i = 0;
+ while (len) {
+ blen = min_t(int, len, UBIFS_BLOCK_SIZE);
+ data_key_init(c, &key, inode->i_ino, block);
+ err = ubifs_jnl_write_data(c, inode, &key, addr, blen);
+ if (err)
+ break;
+ if (++i >= UBIFS_BLOCKS_PER_PAGE)
+ break;
+ block += 1;
+ addr += blen;
+ len -= blen;
+ }
+ if (err) {
+ SetPageError(page);
+ ubifs_err("cannot write page %lu of inode %lu, error %d",
+ page->index, inode->i_ino, err);
+ ubifs_ro_mode(c, err);
+ }
+
+ ubifs_assert(PagePrivate(page));
+ if (PageChecked(page))
+ release_new_page_budget(c);
+ else
+ release_existing_page_budget(c);
+
+ atomic_long_dec(&c->dirty_pg_cnt);
+ ClearPagePrivate(page);
+ ClearPageChecked(page);
+
+ kunmap(page);
+ unlock_page(page);
+ end_page_writeback(page);
+ return err;
+}
+
+/*
+ * When writing-back dirty inodes, VFS first writes-back pages belonging to the
+ * inode, then the inode itself. For UBIFS this may cause a problem. Consider a
+ * situation when a we have an inode with size 0, then a megabyte of data is
+ * appended to the inode, then write-back starts and flushes some amount of the
+ * dirty pages, the journal becomes full, commit happens and finishes, and then
+ * an unclean reboot happens. When the file system is mounted next time, the
+ * inode size would still be 0, but there would be many pages which are beyond
+ * the inode size, they would be indexed and consume flash space. Because the
+ * journal has been committed, the replay would not be able to detect this
+ * situation and correct the inode size. This means UBIFS would have to scan
+ * whole index and correct all inode sizes, which is long an unacceptable.
+ *
+ * To prevent situations like this, UBIFS writes pages back only if they are
+ * within last synchronized inode size, i.e. the the size which has been
+ * written to the flash media last time. Otherwise, UBIFS forces inode
+ * write-back, thus making sure the on-flash inode contains current inode size,
+ * and then keeps writing pages back.
+ *
+ * Some locking issues explanation. 'ubifs_writepage()' first is called with
+ * the page locked, and it locks @ui_mutex. However, write-back does take inode
+ * @i_mutex, which means other VFS operations may be run on this inode at the
+ * same time. And the problematic one is truncation to smaller size, from where
+ * we have to call 'vmtruncate()', which first changes @inode->i_size, then
+ * drops the truncated pages. And while dropping the pages, it takes the page
+ * lock. This means that 'do_truncation()' cannot call 'vmtruncate()' with
+ * @ui_mutex locked, because it would deadlock with 'ubifs_writepage()'. This
+ * means that @inode->i_size is changed while @ui_mutex is unlocked.
+ *
+ * But in 'ubifs_writepage()' we have to guarantee that we do not write beyond
+ * inode size. How do we do this if @inode->i_size may became smaller while we
+ * are in the middle of 'ubifs_writepage()'? The UBIFS solution is the
+ * @ui->ui_isize "shadow" field which UBIFS uses instead of @inode->i_size
+ * internally and updates it under @ui_mutex.
+ *
+ * Q: why we do not worry that if we race with truncation, we may end up with a
+ * situation when the inode is truncated while we are in the middle of
+ * 'do_writepage()', so we do write beyond inode size?
+ * A: If we are in the middle of 'do_writepage()', truncation would be locked
+ * on the page lock and it would not write the truncated inode node to the
+ * journal before we have finished.
+ */
+static int ubifs_writepage(struct page *page, struct writeback_control *wbc)
+{
+ struct inode *inode = page->mapping->host;
+ struct ubifs_inode *ui = ubifs_inode(inode);
+ loff_t i_size = i_size_read(inode), synced_i_size;
+ pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
+ int err, len = i_size & (PAGE_CACHE_SIZE - 1);
+ void *kaddr;
+
+ dbg_gen("ino %lu, pg %lu, pg flags %#lx",
+ inode->i_ino, page->index, page->flags);
+ ubifs_assert(PagePrivate(page));
+
+ /* Is the page fully outside @i_size? (truncate in progress) */
+ if (page->index > end_index || (page->index == end_index && !len)) {
+ err = 0;
+ goto out_unlock;
+ }
+
+ spin_lock(&ui->ui_lock);
+ synced_i_size = ui->synced_i_size;
+ spin_unlock(&ui->ui_lock);
+
+ /* Is the page fully inside @i_size? */
+ if (page->index < end_index) {
+ if (page->index >= synced_i_size >> PAGE_CACHE_SHIFT) {
+ err = inode->i_sb->s_op->write_inode(inode, 1);
+ if (err)
+ goto out_unlock;
+ /*
+ * The inode has been written, but the write-buffer has
+ * not been synchronized, so in case of an unclean
+ * reboot we may end up with some pages beyond inode
+ * size, but they would be in the journal (because
+ * commit flushes write buffers) and recovery would deal
+ * with this.
+ */
+ }
+ return do_writepage(page, PAGE_CACHE_SIZE);
+ }
+
+ /*
+ * The page straddles @i_size. It must be zeroed out on each and every
+ * writepage invocation because it may be mmapped. "A file is mapped
+ * in multiples of the page size. For a file that is not a multiple of
+ * the page size, the remaining memory is zeroed when mapped, and
+ * writes to that region are not written out to the file."
+ */
+ kaddr = kmap_atomic(page, KM_USER0);
+ memset(kaddr + len, 0, PAGE_CACHE_SIZE - len);
+ flush_dcache_page(page);
+ kunmap_atomic(kaddr, KM_USER0);
+
+ if (i_size > synced_i_size) {
+ err = inode->i_sb->s_op->write_inode(inode, 1);
+ if (err)
+ goto out_unlock;
+ }
+
+ return do_writepage(page, len);
+
+out_unlock:
+ unlock_page(page);
+ return err;
+}
+
+/**
+ * do_attr_changes - change inode attributes.
+ * @inode: inode to change attributes for
+ * @attr: describes attributes to change
+ */
+static void do_attr_changes(struct inode *inode, const struct iattr *attr)
+{
+ if (attr->ia_valid & ATTR_UID)
+ inode->i_uid = attr->ia_uid;
+ if (attr->ia_valid & ATTR_GID)
+ inode->i_gid = attr->ia_gid;
+ if (attr->ia_valid & ATTR_ATIME)
+ inode->i_atime = timespec_trunc(attr->ia_atime,
+ inode->i_sb->s_time_gran);
+ if (attr->ia_valid & ATTR_MTIME)
+ inode->i_mtime = timespec_trunc(attr->ia_mtime,
+ inode->i_sb->s_time_gran);
+ if (attr->ia_valid & ATTR_CTIME)
+ inode->i_ctime = timespec_trunc(attr->ia_ctime,
+ inode->i_sb->s_time_gran);
+ if (attr->ia_valid & ATTR_MODE) {
+ umode_t mode = attr->ia_mode;
+
+ if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID))
+ mode &= ~S_ISGID;
+ inode->i_mode = mode;
+ }
+}
+
+/**
+ * do_truncation - truncate an inode.
+ * @c: UBIFS file-system description object
+ * @inode: inode to truncate
+ * @attr: inode attribute changes description
+ *
+ * This function implements VFS '->setattr()' call when the inode is truncated
+ * to a smaller size. Returns zero in case of success and a negative error code
+ * in case of failure.
+ */
+static int do_truncation(struct ubifs_info *c, struct inode *inode,
+ const struct iattr *attr)
+{
+ int err;
+ struct ubifs_budget_req req;
+ loff_t old_size = inode->i_size, new_size = attr->ia_size;
+ int offset = new_size & (UBIFS_BLOCK_SIZE - 1);
+ struct ubifs_inode *ui = ubifs_inode(inode);
+
+ dbg_gen("ino %lu, size %lld -> %lld", inode->i_ino, old_size, new_size);
+ memset(&req, 0, sizeof(struct ubifs_budget_req));
+
+ /*
+ * If this is truncation to a smaller size, and we do not truncate on a
+ * block boundary, budget for changing one data block, because the last
+ * block will be re-written.
+ */
+ if (new_size & (UBIFS_BLOCK_SIZE - 1))
+ req.dirtied_page = 1;
+
+ req.dirtied_ino = 1;
+ /* A funny way to budget for truncation node */
+ req.dirtied_ino_d = UBIFS_TRUN_NODE_SZ;
+ err = ubifs_budget_space(c, &req);
+ if (err)
+ return err;
+
+ err = vmtruncate(inode, new_size);
+ if (err)
+ goto out_budg;
+
+ if (offset) {
+ pgoff_t index = new_size >> PAGE_CACHE_SHIFT;
+ struct page *page;
+
+ page = find_lock_page(inode->i_mapping, index);
+ if (page) {
+ if (PageDirty(page)) {
+ /*
+ * 'ubifs_jnl_truncate()' will try to truncate
+ * the last data node, but it contains
+ * out-of-date data because the page is dirty.
+ * Write the page now, so that
+ * 'ubifs_jnl_truncate()' will see an already
+ * truncated (and up to date) data node.
+ */
+ ubifs_assert(PagePrivate(page));
+
+ clear_page_dirty_for_io(page);
+ if (UBIFS_BLOCKS_PER_PAGE_SHIFT)
+ offset = new_size &
+ (PAGE_CACHE_SIZE - 1);
+ err = do_writepage(page, offset);
+ page_cache_release(page);
+ if (err)
+ goto out_budg;
+ /*
+ * We could now tell 'ubifs_jnl_truncate()' not
+ * to read the last block.
+ */
+ } else {
+ /*
+ * We could 'kmap()' the page and pass the data
+ * to 'ubifs_jnl_truncate()' to save it from
+ * having to read it.
+ */
+ unlock_page(page);
+ page_cache_release(page);
+ }
+ }
+ }
+
+ mutex_lock(&ui->ui_mutex);
+ ui->ui_size = inode->i_size;
+ /* Truncation changes inode [mc]time */
+ inode->i_mtime = inode->i_ctime = ubifs_current_time(inode);
+ /* The other attributes may be changed at the same time as well */
+ do_attr_changes(inode, attr);
+
+ err = ubifs_jnl_truncate(c, inode, old_size, new_size);
+ mutex_unlock(&ui->ui_mutex);
+out_budg:
+ ubifs_release_budget(c, &req);
+ return err;
+}
+
+/**
+ * do_setattr - change inode attributes.
+ * @c: UBIFS file-system description object
+ * @inode: inode to change attributes for
+ * @attr: inode attribute changes description
+ *
+ * This function implements VFS '->setattr()' call for all cases except
+ * truncations to smaller size. Returns zero in case of success and a negative
+ * error code in case of failure.
+ */
+static int do_setattr(struct ubifs_info *c, struct inode *inode,
+ const struct iattr *attr)
+{
+ int err, release;
+ loff_t new_size = attr->ia_size;
+ struct ubifs_inode *ui = ubifs_inode(inode);
+ struct ubifs_budget_req req = { .dirtied_ino = 1,
+ .dirtied_ino_d = ui->data_len };
+
+ err = ubifs_budget_space(c, &req);
+ if (err)
+ return err;
+
+ if (attr->ia_valid & ATTR_SIZE) {
+ dbg_gen("size %lld -> %lld", inode->i_size, new_size);
+ err = vmtruncate(inode, new_size);
+ if (err)
+ goto out;
+ }
+
+ mutex_lock(&ui->ui_mutex);
+ if (attr->ia_valid & ATTR_SIZE) {
+ /* Truncation changes inode [mc]time */
+ inode->i_mtime = inode->i_ctime = ubifs_current_time(inode);
+ /* 'vmtruncate()' changed @i_size, update @ui_size */
+ ui->ui_size = inode->i_size;
+ }
+
+ do_attr_changes(inode, attr);
+
+ release = ui->dirty;
+ if (attr->ia_valid & ATTR_SIZE)
+ /*
+ * Inode length changed, so we have to make sure
+ * @I_DIRTY_DATASYNC is set.
+ */
+ __mark_inode_dirty(inode, I_DIRTY_SYNC | I_DIRTY_DATASYNC);
+ else
+ mark_inode_dirty_sync(inode);
+ mutex_unlock(&ui->ui_mutex);
+
+ if (release)
+ ubifs_release_budget(c, &req);
+ if (IS_SYNC(inode))
+ err = inode->i_sb->s_op->write_inode(inode, 1);
+ return err;
+
+out:
+ ubifs_release_budget(c, &req);
+ return err;
+}
+
+int ubifs_setattr(struct dentry *dentry, struct iattr *attr)
+{
+ int err;
+ struct inode *inode = dentry->d_inode;
+ struct ubifs_info *c = inode->i_sb->s_fs_info;
+
+ dbg_gen("ino %lu, ia_valid %#x", inode->i_ino, attr->ia_valid);
+ err = inode_change_ok(inode, attr);
+ if (err)
+ return err;
+
+ err = dbg_check_synced_i_size(inode);
+ if (err)
+ return err;
+
+ if ((attr->ia_valid & ATTR_SIZE) && attr->ia_size < inode->i_size)
+ /* Truncation to a smaller size */
+ err = do_truncation(c, inode, attr);
+ else
+ err = do_setattr(c, inode, attr);
+
+ return err;
+}
+
+static void ubifs_invalidatepage(struct page *page, unsigned long offset)
+{
+ struct inode *inode = page->mapping->host;
+ struct ubifs_info *c = inode->i_sb->s_fs_info;
+
+ ubifs_assert(PagePrivate(page));
+ if (offset)
+ /* Partial page remains dirty */
+ return;
+
+ if (PageChecked(page))
+ release_new_page_budget(c);
+ else
+ release_existing_page_budget(c);
+
+ atomic_long_dec(&c->dirty_pg_cnt);
+ ClearPagePrivate(page);
+ ClearPageChecked(page);
+}
+
+static void *ubifs_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+ struct ubifs_inode *ui = ubifs_inode(dentry->d_inode);
+
+ nd_set_link(nd, ui->data);
+ return NULL;
+}
+
+int ubifs_fsync(struct file *file, struct dentry *dentry, int datasync)
+{
+ struct inode *inode = dentry->d_inode;
+ struct ubifs_info *c = inode->i_sb->s_fs_info;
+ int err;
+
+ dbg_gen("syncing inode %lu", inode->i_ino);
+
+ /*
+ * VFS has already synchronized dirty pages for this inode. Synchronize
+ * the inode unless this is a 'datasync()' call.
+ */
+ if (!datasync || (inode->i_state & I_DIRTY_DATASYNC)) {
+ err = inode->i_sb->s_op->write_inode(inode, 1);
+ if (err)
+ return err;
+ }
+
+ /*
+ * Nodes related to this inode may still sit in a write-buffer. Flush
+ * them.
+ */
+ err = ubifs_sync_wbufs_by_inode(c, inode);
+ if (err)
+ return err;
+
+ return 0;
+}
+
+/**
+ * mctime_update_needed - check if mtime or ctime update is needed.
+ * @inode: the inode to do the check for
+ * @now: current time
+ *
+ * This helper function checks if the inode mtime/ctime should be updated or
+ * not. If current values of the time-stamps are within the UBIFS inode time
+ * granularity, they are not updated. This is an optimization.
+ */
+static inline int mctime_update_needed(const struct inode *inode,
+ const struct timespec *now)
+{
+ if (!timespec_equal(&inode->i_mtime, now) ||
+ !timespec_equal(&inode->i_ctime, now))
+ return 1;
+ return 0;
+}
+
+/**
+ * update_ctime - update mtime and ctime of an inode.
+ * @c: UBIFS file-system description object
+ * @inode: inode to update
+ *
+ * This function updates mtime and ctime of the inode if it is not equivalent to
+ * current time. Returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int update_mctime(struct ubifs_info *c, struct inode *inode)
+{
+ struct timespec now = ubifs_current_time(inode);
+ struct ubifs_inode *ui = ubifs_inode(inode);
+
+ if (mctime_update_needed(inode, &now)) {
+ int err, release;
+ struct ubifs_budget_req req = { .dirtied_ino = 1,
+ .dirtied_ino_d = ui->data_len };
+
+ err = ubifs_budget_space(c, &req);
+ if (err)
+ return err;
+
+ mutex_lock(&ui->ui_mutex);
+ inode->i_mtime = inode->i_ctime = ubifs_current_time(inode);
+ release = ui->dirty;
+ mark_inode_dirty_sync(inode);
+ mutex_unlock(&ui->ui_mutex);
+ if (release)
+ ubifs_release_budget(c, &req);
+ }
+
+ return 0;
+}
+
+static ssize_t ubifs_aio_write(struct kiocb *iocb, const struct iovec *iov,
+ unsigned long nr_segs, loff_t pos)
+{
+ int err;
+ ssize_t ret;
+ struct inode *inode = iocb->ki_filp->f_mapping->host;
+ struct ubifs_info *c = inode->i_sb->s_fs_info;
+
+ err = update_mctime(c, inode);
+ if (err)
+ return err;
+
+ ret = generic_file_aio_write(iocb, iov, nr_segs, pos);
+ if (ret < 0)
+ return ret;
+
+ if (ret > 0 && (IS_SYNC(inode) || iocb->ki_filp->f_flags & O_SYNC)) {
+ err = ubifs_sync_wbufs_by_inode(c, inode);
+ if (err)
+ return err;
+ }
+
+ return ret;
+}
+
+static int ubifs_set_page_dirty(struct page *page)
+{
+ int ret;
+
+ ret = __set_page_dirty_nobuffers(page);
+ /*
+ * An attempt to dirty a page without budgeting for it - should not
+ * happen.
+ */
+ ubifs_assert(ret == 0);
+ return ret;
+}
+
+static int ubifs_releasepage(struct page *page, gfp_t unused_gfp_flags)
+{
+ /*
+ * An attempt to release a dirty page without budgeting for it - should
+ * not happen.
+ */
+ if (PageWriteback(page))
+ return 0;
+ ubifs_assert(PagePrivate(page));
+ ubifs_assert(0);
+ ClearPagePrivate(page);
+ ClearPageChecked(page);
+ return 1;
+}
+
+/*
+ * mmap()d file has taken write protection fault and is being made
+ * writable. UBIFS must ensure page is budgeted for.
+ */
+static int ubifs_vm_page_mkwrite(struct vm_area_struct *vma, struct page *page)
+{
+ struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
+ struct ubifs_info *c = inode->i_sb->s_fs_info;
+ struct timespec now = ubifs_current_time(inode);
+ struct ubifs_budget_req req = { .new_page = 1 };
+ int err, update_time;
+
+ dbg_gen("ino %lu, pg %lu, i_size %lld", inode->i_ino, page->index,
+ i_size_read(inode));
+ ubifs_assert(!(inode->i_sb->s_flags & MS_RDONLY));
+
+ if (unlikely(c->ro_media))
+ return -EROFS;
+
+ /*
+ * We have not locked @page so far so we may budget for changing the
+ * page. Note, we cannot do this after we locked the page, because
+ * budgeting may cause write-back which would cause deadlock.
+ *
+ * At the moment we do not know whether the page is dirty or not, so we
+ * assume that it is not and budget for a new page. We could look at
+ * the @PG_private flag and figure this out, but we may race with write
+ * back and the page state may change by the time we lock it, so this
+ * would need additional care. We do not bother with this at the
+ * moment, although it might be good idea to do. Instead, we allocate
+ * budget for a new page and amend it later on if the page was in fact
+ * dirty.
+ *
+ * The budgeting-related logic of this function is similar to what we
+ * do in 'ubifs_write_begin()' and 'ubifs_write_end()'. Glance there
+ * for more comments.
+ */
+ update_time = mctime_update_needed(inode, &now);
+ if (update_time)
+ /*
+ * We have to change inode time stamp which requires extra
+ * budgeting.
+ */
+ req.dirtied_ino = 1;
+
+ err = ubifs_budget_space(c, &req);
+ if (unlikely(err)) {
+ if (err == -ENOSPC)
+ ubifs_warn("out of space for mmapped file "
+ "(inode number %lu)", inode->i_ino);
+ return err;
+ }
+
+ lock_page(page);
+ if (unlikely(page->mapping != inode->i_mapping ||
+ page_offset(page) > i_size_read(inode))) {
+ /* Page got truncated out from underneath us */
+ err = -EINVAL;
+ goto out_unlock;
+ }
+
+ if (PagePrivate(page))
+ release_new_page_budget(c);
+ else {
+ if (!PageChecked(page))
+ ubifs_convert_page_budget(c);
+ SetPagePrivate(page);
+ atomic_long_inc(&c->dirty_pg_cnt);
+ __set_page_dirty_nobuffers(page);
+ }
+
+ if (update_time) {
+ int release;
+ struct ubifs_inode *ui = ubifs_inode(inode);
+
+ mutex_lock(&ui->ui_mutex);
+ inode->i_mtime = inode->i_ctime = ubifs_current_time(inode);
+ release = ui->dirty;
+ mark_inode_dirty_sync(inode);
+ mutex_unlock(&ui->ui_mutex);
+ if (release)
+ ubifs_release_dirty_inode_budget(c, ui);
+ }
+
+ unlock_page(page);
+ return 0;
+
+out_unlock:
+ unlock_page(page);
+ ubifs_release_budget(c, &req);
+ return err;
+}
+
+static struct vm_operations_struct ubifs_file_vm_ops = {
+ .fault = filemap_fault,
+ .page_mkwrite = ubifs_vm_page_mkwrite,
+};
+
+static int ubifs_file_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ int err;
+
+ /* 'generic_file_mmap()' takes care of NOMMU case */
+ err = generic_file_mmap(file, vma);
+ if (err)
+ return err;
+ vma->vm_ops = &ubifs_file_vm_ops;
+ return 0;
+}
+
+struct address_space_operations ubifs_file_address_operations = {
+ .readpage = ubifs_readpage,
+ .writepage = ubifs_writepage,
+ .write_begin = ubifs_write_begin,
+ .write_end = ubifs_write_end,
+ .invalidatepage = ubifs_invalidatepage,
+ .set_page_dirty = ubifs_set_page_dirty,
+ .releasepage = ubifs_releasepage,
+};
+
+struct inode_operations ubifs_file_inode_operations = {
+ .setattr = ubifs_setattr,
+ .getattr = ubifs_getattr,
+#ifdef CONFIG_UBIFS_FS_XATTR
+ .setxattr = ubifs_setxattr,
+ .getxattr = ubifs_getxattr,
+ .listxattr = ubifs_listxattr,
+ .removexattr = ubifs_removexattr,
+#endif
+};
+
+struct inode_operations ubifs_symlink_inode_operations = {
+ .readlink = generic_readlink,
+ .follow_link = ubifs_follow_link,
+ .setattr = ubifs_setattr,
+ .getattr = ubifs_getattr,
+};
+
+struct file_operations ubifs_file_operations = {
+ .llseek = generic_file_llseek,
+ .read = do_sync_read,
+ .write = do_sync_write,
+ .aio_read = generic_file_aio_read,
+ .aio_write = ubifs_aio_write,
+ .mmap = ubifs_file_mmap,
+ .fsync = ubifs_fsync,
+ .unlocked_ioctl = ubifs_ioctl,
+ .splice_read = generic_file_splice_read,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = ubifs_compat_ioctl,
+#endif
+};
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ * Adrian Hunter
+ */
+
+/*
+ * This file contains functions for finding LEBs for various purposes e.g.
+ * garbage collection. In general, lprops category heaps and lists are used
+ * for fast access, falling back on scanning the LPT as a last resort.
+ */
+
+#include <linux/sort.h>
+#include "ubifs.h"
+
+/**
+ * struct scan_data - data provided to scan callback functions
+ * @min_space: minimum number of bytes for which to scan
+ * @pick_free: whether it is OK to scan for empty LEBs
+ * @lnum: LEB number found is returned here
+ * @exclude_index: whether to exclude index LEBs
+ */
+struct scan_data {
+ int min_space;
+ int pick_free;
+ int lnum;
+ int exclude_index;
+};
+
+/**
+ * valuable - determine whether LEB properties are valuable.
+ * @c: the UBIFS file-system description object
+ * @lprops: LEB properties
+ *
+ * This function return %1 if the LEB properties should be added to the LEB
+ * properties tree in memory. Otherwise %0 is returned.
+ */
+static int valuable(struct ubifs_info *c, const struct ubifs_lprops *lprops)
+{
+ int n, cat = lprops->flags & LPROPS_CAT_MASK;
+ struct ubifs_lpt_heap *heap;
+
+ switch (cat) {
+ case LPROPS_DIRTY:
+ case LPROPS_DIRTY_IDX:
+ case LPROPS_FREE:
+ heap = &c->lpt_heap[cat - 1];
+ if (heap->cnt < heap->max_cnt)
+ return 1;
+ if (lprops->free + lprops->dirty >= c->dark_wm)
+ return 1;
+ return 0;
+ case LPROPS_EMPTY:
+ n = c->lst.empty_lebs + c->freeable_cnt -
+ c->lst.taken_empty_lebs;
+ if (n < c->lsave_cnt)
+ return 1;
+ return 0;
+ case LPROPS_FREEABLE:
+ return 1;
+ case LPROPS_FRDI_IDX:
+ return 1;
+ }
+ return 0;
+}
+
+/**
+ * scan_for_dirty_cb - dirty space scan callback.
+ * @c: the UBIFS file-system description object
+ * @lprops: LEB properties to scan
+ * @in_tree: whether the LEB properties are in main memory
+ * @data: information passed to and from the caller of the scan
+ *
+ * This function returns a code that indicates whether the scan should continue
+ * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree
+ * in main memory (%LPT_SCAN_ADD), or whether the scan should stop
+ * (%LPT_SCAN_STOP).
+ */
+static int scan_for_dirty_cb(struct ubifs_info *c,
+ const struct ubifs_lprops *lprops, int in_tree,
+ struct scan_data *data)
+{
+ int ret = LPT_SCAN_CONTINUE;
+
+ /* Exclude LEBs that are currently in use */
+ if (lprops->flags & LPROPS_TAKEN)
+ return LPT_SCAN_CONTINUE;
+ /* Determine whether to add these LEB properties to the tree */
+ if (!in_tree && valuable(c, lprops))
+ ret |= LPT_SCAN_ADD;
+ /* Exclude LEBs with too little space */
+ if (lprops->free + lprops->dirty < data->min_space)
+ return ret;
+ /* If specified, exclude index LEBs */
+ if (data->exclude_index && lprops->flags & LPROPS_INDEX)
+ return ret;
+ /* If specified, exclude empty or freeable LEBs */
+ if (lprops->free + lprops->dirty == c->leb_size) {
+ if (!data->pick_free)
+ return ret;
+ /* Exclude LEBs with too little dirty space (unless it is empty) */
+ } else if (lprops->dirty < c->dead_wm)
+ return ret;
+ /* Finally we found space */
+ data->lnum = lprops->lnum;
+ return LPT_SCAN_ADD | LPT_SCAN_STOP;
+}
+
+/**
+ * scan_for_dirty - find a data LEB with free space.
+ * @c: the UBIFS file-system description object
+ * @min_space: minimum amount free plus dirty space the returned LEB has to
+ * have
+ * @pick_free: if it is OK to return a free or freeable LEB
+ * @exclude_index: whether to exclude index LEBs
+ *
+ * This function returns a pointer to the LEB properties found or a negative
+ * error code.
+ */
+static const struct ubifs_lprops *scan_for_dirty(struct ubifs_info *c,
+ int min_space, int pick_free,
+ int exclude_index)
+{
+ const struct ubifs_lprops *lprops;
+ struct ubifs_lpt_heap *heap;
+ struct scan_data data;
+ int err, i;
+
+ /* There may be an LEB with enough dirty space on the free heap */
+ heap = &c->lpt_heap[LPROPS_FREE - 1];
+ for (i = 0; i < heap->cnt; i++) {
+ lprops = heap->arr[i];
+ if (lprops->free + lprops->dirty < min_space)
+ continue;
+ if (lprops->dirty < c->dead_wm)
+ continue;
+ return lprops;
+ }
+ /*
+ * A LEB may have fallen off of the bottom of the dirty heap, and ended
+ * up as uncategorized even though it has enough dirty space for us now,
+ * so check the uncategorized list. N.B. neither empty nor freeable LEBs
+ * can end up as uncategorized because they are kept on lists not
+ * finite-sized heaps.
+ */
+ list_for_each_entry(lprops, &c->uncat_list, list) {
+ if (lprops->flags & LPROPS_TAKEN)
+ continue;
+ if (lprops->free + lprops->dirty < min_space)
+ continue;
+ if (exclude_index && (lprops->flags & LPROPS_INDEX))
+ continue;
+ if (lprops->dirty < c->dead_wm)
+ continue;
+ return lprops;
+ }
+ /* We have looked everywhere in main memory, now scan the flash */
+ if (c->pnodes_have >= c->pnode_cnt)
+ /* All pnodes are in memory, so skip scan */
+ return ERR_PTR(-ENOSPC);
+ data.min_space = min_space;
+ data.pick_free = pick_free;
+ data.lnum = -1;
+ data.exclude_index = exclude_index;
+ err = ubifs_lpt_scan_nolock(c, -1, c->lscan_lnum,
+ (ubifs_lpt_scan_callback)scan_for_dirty_cb,
+ &data);
+ if (err)
+ return ERR_PTR(err);
+ ubifs_assert(data.lnum >= c->main_first && data.lnum < c->leb_cnt);
+ c->lscan_lnum = data.lnum;
+ lprops = ubifs_lpt_lookup_dirty(c, data.lnum);
+ if (IS_ERR(lprops))
+ return lprops;
+ ubifs_assert(lprops->lnum == data.lnum);
+ ubifs_assert(lprops->free + lprops->dirty >= min_space);
+ ubifs_assert(lprops->dirty >= c->dead_wm ||
+ (pick_free &&
+ lprops->free + lprops->dirty == c->leb_size));
+ ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
+ ubifs_assert(!exclude_index || !(lprops->flags & LPROPS_INDEX));
+ return lprops;
+}
+
+/**
+ * ubifs_find_dirty_leb - find a dirty LEB for the Garbage Collector.
+ * @c: the UBIFS file-system description object
+ * @ret_lp: LEB properties are returned here on exit
+ * @min_space: minimum amount free plus dirty space the returned LEB has to
+ * have
+ * @pick_free: controls whether it is OK to pick empty or index LEBs
+ *
+ * This function tries to find a dirty logical eraseblock which has at least
+ * @min_space free and dirty space. It prefers to take an LEB from the dirty or
+ * dirty index heap, and it falls-back to LPT scanning if the heaps are empty
+ * or do not have an LEB which satisfies the @min_space criteria.
+ *
+ * Note:
+ * o LEBs which have less than dead watermark of dirty space are never picked
+ * by this function;
+ *
+ * Returns zero and the LEB properties of
+ * found dirty LEB in case of success, %-ENOSPC if no dirty LEB was found and a
+ * negative error code in case of other failures. The returned LEB is marked as
+ * "taken".
+ *
+ * The additional @pick_free argument controls if this function has to return a
+ * free or freeable LEB if one is present. For example, GC must to set it to %1,
+ * when called from the journal space reservation function, because the
+ * appearance of free space may coincide with the loss of enough dirty space
+ * for GC to succeed anyway.
+ *
+ * In contrast, if the Garbage Collector is called from budgeting, it should
+ * just make free space, not return LEBs which are already free or freeable.
+ *
+ * In addition @pick_free is set to %2 by the recovery process in order to
+ * recover gc_lnum in which case an index LEB must not be returned.
+ */
+int ubifs_find_dirty_leb(struct ubifs_info *c, struct ubifs_lprops *ret_lp,
+ int min_space, int pick_free)
+{
+ int err = 0, sum, exclude_index = pick_free == 2 ? 1 : 0;
+ const struct ubifs_lprops *lp = NULL, *idx_lp = NULL;
+ struct ubifs_lpt_heap *heap, *idx_heap;
+
+ ubifs_get_lprops(c);
+
+ if (pick_free) {
+ int lebs, rsvd_idx_lebs = 0;
+
+ spin_lock(&c->space_lock);
+ lebs = c->lst.empty_lebs;
+ lebs += c->freeable_cnt - c->lst.taken_empty_lebs;
+
+ /*
+ * Note, the index may consume more LEBs than have been reserved
+ * for it. It is OK because it might be consolidated by GC.
+ * But if the index takes fewer LEBs than it is reserved for it,
+ * this function must avoid picking those reserved LEBs.
+ */
+ if (c->min_idx_lebs >= c->lst.idx_lebs) {
+ rsvd_idx_lebs = c->min_idx_lebs - c->lst.idx_lebs;
+ exclude_index = 1;
+ }
+ spin_unlock(&c->space_lock);
+
+ /* Check if there are enough free LEBs for the index */
+ if (rsvd_idx_lebs < lebs) {
+ /* OK, try to find an empty LEB */
+ lp = ubifs_fast_find_empty(c);
+ if (lp)
+ goto found;
+
+ /* Or a freeable LEB */
+ lp = ubifs_fast_find_freeable(c);
+ if (lp)
+ goto found;
+ } else
+ /*
+ * We cannot pick free/freeable LEBs in the below code.
+ */
+ pick_free = 0;
+ } else {
+ spin_lock(&c->space_lock);
+ exclude_index = (c->min_idx_lebs >= c->lst.idx_lebs);
+ spin_unlock(&c->space_lock);
+ }
+
+ /* Look on the dirty and dirty index heaps */
+ heap = &c->lpt_heap[LPROPS_DIRTY - 1];
+ idx_heap = &c->lpt_heap[LPROPS_DIRTY_IDX - 1];
+
+ if (idx_heap->cnt && !exclude_index) {
+ idx_lp = idx_heap->arr[0];
+ sum = idx_lp->free + idx_lp->dirty;
+ /*
+ * Since we reserve twice as more space for the index than it
+ * actually takes, it does not make sense to pick indexing LEBs
+ * with less than half LEB of dirty space.
+ */
+ if (sum < min_space || sum < c->half_leb_size)
+ idx_lp = NULL;
+ }
+
+ if (heap->cnt) {
+ lp = heap->arr[0];
+ if (lp->dirty + lp->free < min_space)
+ lp = NULL;
+ }
+
+ /* Pick the LEB with most space */
+ if (idx_lp && lp) {
+ if (idx_lp->free + idx_lp->dirty >= lp->free + lp->dirty)
+ lp = idx_lp;
+ } else if (idx_lp && !lp)
+ lp = idx_lp;
+
+ if (lp) {
+ ubifs_assert(lp->dirty >= c->dead_wm);
+ goto found;
+ }
+
+ /* Did not find a dirty LEB on the dirty heaps, have to scan */
+ dbg_find("scanning LPT for a dirty LEB");
+ lp = scan_for_dirty(c, min_space, pick_free, exclude_index);
+ if (IS_ERR(lp)) {
+ err = PTR_ERR(lp);
+ goto out;
+ }
+ ubifs_assert(lp->dirty >= c->dead_wm ||
+ (pick_free && lp->free + lp->dirty == c->leb_size));
+
+found:
+ dbg_find("found LEB %d, free %d, dirty %d, flags %#x",
+ lp->lnum, lp->free, lp->dirty, lp->flags);
+
+ lp = ubifs_change_lp(c, lp, LPROPS_NC, LPROPS_NC,
+ lp->flags | LPROPS_TAKEN, 0);
+ if (IS_ERR(lp)) {
+ err = PTR_ERR(lp);
+ goto out;
+ }
+
+ memcpy(ret_lp, lp, sizeof(struct ubifs_lprops));
+
+out:
+ ubifs_release_lprops(c);
+ return err;
+}
+
+/**
+ * scan_for_free_cb - free space scan callback.
+ * @c: the UBIFS file-system description object
+ * @lprops: LEB properties to scan
+ * @in_tree: whether the LEB properties are in main memory
+ * @data: information passed to and from the caller of the scan
+ *
+ * This function returns a code that indicates whether the scan should continue
+ * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree
+ * in main memory (%LPT_SCAN_ADD), or whether the scan should stop
+ * (%LPT_SCAN_STOP).
+ */
+static int scan_for_free_cb(struct ubifs_info *c,
+ const struct ubifs_lprops *lprops, int in_tree,
+ struct scan_data *data)
+{
+ int ret = LPT_SCAN_CONTINUE;
+
+ /* Exclude LEBs that are currently in use */
+ if (lprops->flags & LPROPS_TAKEN)
+ return LPT_SCAN_CONTINUE;
+ /* Determine whether to add these LEB properties to the tree */
+ if (!in_tree && valuable(c, lprops))
+ ret |= LPT_SCAN_ADD;
+ /* Exclude index LEBs */
+ if (lprops->flags & LPROPS_INDEX)
+ return ret;
+ /* Exclude LEBs with too little space */
+ if (lprops->free < data->min_space)
+ return ret;
+ /* If specified, exclude empty LEBs */
+ if (!data->pick_free && lprops->free == c->leb_size)
+ return ret;
+ /*
+ * LEBs that have only free and dirty space must not be allocated
+ * because they may have been unmapped already or they may have data
+ * that is obsolete only because of nodes that are still sitting in a
+ * wbuf.
+ */
+ if (lprops->free + lprops->dirty == c->leb_size && lprops->dirty > 0)
+ return ret;
+ /* Finally we found space */
+ data->lnum = lprops->lnum;
+ return LPT_SCAN_ADD | LPT_SCAN_STOP;
+}
+
+/**
+ * do_find_free_space - find a data LEB with free space.
+ * @c: the UBIFS file-system description object
+ * @min_space: minimum amount of free space required
+ * @pick_free: whether it is OK to scan for empty LEBs
+ * @squeeze: whether to try to find space in a non-empty LEB first
+ *
+ * This function returns a pointer to the LEB properties found or a negative
+ * error code.
+ */
+static
+const struct ubifs_lprops *do_find_free_space(struct ubifs_info *c,
+ int min_space, int pick_free,
+ int squeeze)
+{
+ const struct ubifs_lprops *lprops;
+ struct ubifs_lpt_heap *heap;
+ struct scan_data data;
+ int err, i;
+
+ if (squeeze) {
+ lprops = ubifs_fast_find_free(c);
+ if (lprops && lprops->free >= min_space)
+ return lprops;
+ }
+ if (pick_free) {
+ lprops = ubifs_fast_find_empty(c);
+ if (lprops)
+ return lprops;
+ }
+ if (!squeeze) {
+ lprops = ubifs_fast_find_free(c);
+ if (lprops && lprops->free >= min_space)
+ return lprops;
+ }
+ /* There may be an LEB with enough free space on the dirty heap */
+ heap = &c->lpt_heap[LPROPS_DIRTY - 1];
+ for (i = 0; i < heap->cnt; i++) {
+ lprops = heap->arr[i];
+ if (lprops->free >= min_space)
+ return lprops;
+ }
+ /*
+ * A LEB may have fallen off of the bottom of the free heap, and ended
+ * up as uncategorized even though it has enough free space for us now,
+ * so check the uncategorized list. N.B. neither empty nor freeable LEBs
+ * can end up as uncategorized because they are kept on lists not
+ * finite-sized heaps.
+ */
+ list_for_each_entry(lprops, &c->uncat_list, list) {
+ if (lprops->flags & LPROPS_TAKEN)
+ continue;
+ if (lprops->flags & LPROPS_INDEX)
+ continue;
+ if (lprops->free >= min_space)
+ return lprops;
+ }
+ /* We have looked everywhere in main memory, now scan the flash */
+ if (c->pnodes_have >= c->pnode_cnt)
+ /* All pnodes are in memory, so skip scan */
+ return ERR_PTR(-ENOSPC);
+ data.min_space = min_space;
+ data.pick_free = pick_free;
+ data.lnum = -1;
+ err = ubifs_lpt_scan_nolock(c, -1, c->lscan_lnum,
+ (ubifs_lpt_scan_callback)scan_for_free_cb,
+ &data);
+ if (err)
+ return ERR_PTR(err);
+ ubifs_assert(data.lnum >= c->main_first && data.lnum < c->leb_cnt);
+ c->lscan_lnum = data.lnum;
+ lprops = ubifs_lpt_lookup_dirty(c, data.lnum);
+ if (IS_ERR(lprops))
+ return lprops;
+ ubifs_assert(lprops->lnum == data.lnum);
+ ubifs_assert(lprops->free >= min_space);
+ ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
+ ubifs_assert(!(lprops->flags & LPROPS_INDEX));
+ return lprops;
+}
+
+/**
+ * ubifs_find_free_space - find a data LEB with free space.
+ * @c: the UBIFS file-system description object
+ * @min_space: minimum amount of required free space
+ * @free: contains amount of free space in the LEB on exit
+ * @squeeze: whether to try to find space in a non-empty LEB first
+ *
+ * This function looks for an LEB with at least @min_space bytes of free space.
+ * It tries to find an empty LEB if possible. If no empty LEBs are available,
+ * this function searches for a non-empty data LEB. The returned LEB is marked
+ * as "taken".
+ *
+ * This function returns found LEB number in case of success, %-ENOSPC if it
+ * failed to find a LEB with @min_space bytes of free space and other a negative
+ * error codes in case of failure.
+ */
+int ubifs_find_free_space(struct ubifs_info *c, int min_space, int *free,
+ int squeeze)
+{
+ const struct ubifs_lprops *lprops;
+ int lebs, rsvd_idx_lebs, pick_free = 0, err, lnum, flags;
+
+ dbg_find("min_space %d", min_space);
+ ubifs_get_lprops(c);
+
+ /* Check if there are enough empty LEBs for commit */
+ spin_lock(&c->space_lock);
+ if (c->min_idx_lebs > c->lst.idx_lebs)
+ rsvd_idx_lebs = c->min_idx_lebs - c->lst.idx_lebs;
+ else
+ rsvd_idx_lebs = 0;
+ lebs = c->lst.empty_lebs + c->freeable_cnt + c->idx_gc_cnt -
+ c->lst.taken_empty_lebs;
+ ubifs_assert(lebs + c->lst.idx_lebs >= c->min_idx_lebs);
+ if (rsvd_idx_lebs < lebs)
+ /*
+ * OK to allocate an empty LEB, but we still don't want to go
+ * looking for one if there aren't any.
+ */
+ if (c->lst.empty_lebs - c->lst.taken_empty_lebs > 0) {
+ pick_free = 1;
+ /*
+ * Because we release the space lock, we must account
+ * for this allocation here. After the LEB properties
+ * flags have been updated, we subtract one. Note, the
+ * result of this is that lprops also decreases
+ * @taken_empty_lebs in 'ubifs_change_lp()', so it is
+ * off by one for a short period of time which may
+ * introduce a small disturbance to budgeting
+ * calculations, but this is harmless because at the
+ * worst case this would make the budgeting subsystem
+ * be more pessimistic than needed.
+ *
+ * Fundamentally, this is about serialization of the
+ * budgeting and lprops subsystems. We could make the
+ * @space_lock a mutex and avoid dropping it before
+ * calling 'ubifs_change_lp()', but mutex is more
+ * heavy-weight, and we want budgeting to be as fast as
+ * possible.
+ */
+ c->lst.taken_empty_lebs += 1;
+ }
+ spin_unlock(&c->space_lock);
+
+ lprops = do_find_free_space(c, min_space, pick_free, squeeze);
+ if (IS_ERR(lprops)) {
+ err = PTR_ERR(lprops);
+ goto out;
+ }
+
+ lnum = lprops->lnum;
+ flags = lprops->flags | LPROPS_TAKEN;
+
+ lprops = ubifs_change_lp(c, lprops, LPROPS_NC, LPROPS_NC, flags, 0);
+ if (IS_ERR(lprops)) {
+ err = PTR_ERR(lprops);
+ goto out;
+ }
+
+ if (pick_free) {
+ spin_lock(&c->space_lock);
+ c->lst.taken_empty_lebs -= 1;
+ spin_unlock(&c->space_lock);
+ }
+
+ *free = lprops->free;
+ ubifs_release_lprops(c);
+
+ if (*free == c->leb_size) {
+ /*
+ * Ensure that empty LEBs have been unmapped. They may not have
+ * been, for example, because of an unclean unmount. Also
+ * LEBs that were freeable LEBs (free + dirty == leb_size) will
+ * not have been unmapped.
+ */
+ err = ubifs_leb_unmap(c, lnum);
+ if (err)
+ return err;
+ }
+
+ dbg_find("found LEB %d, free %d", lnum, *free);
+ ubifs_assert(*free >= min_space);
+ return lnum;
+
+out:
+ if (pick_free) {
+ spin_lock(&c->space_lock);
+ c->lst.taken_empty_lebs -= 1;
+ spin_unlock(&c->space_lock);
+ }
+ ubifs_release_lprops(c);
+ return err;
+}
+
+/**
+ * scan_for_idx_cb - callback used by the scan for a free LEB for the index.
+ * @c: the UBIFS file-system description object
+ * @lprops: LEB properties to scan
+ * @in_tree: whether the LEB properties are in main memory
+ * @data: information passed to and from the caller of the scan
+ *
+ * This function returns a code that indicates whether the scan should continue
+ * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree
+ * in main memory (%LPT_SCAN_ADD), or whether the scan should stop
+ * (%LPT_SCAN_STOP).
+ */
+static int scan_for_idx_cb(struct ubifs_info *c,
+ const struct ubifs_lprops *lprops, int in_tree,
+ struct scan_data *data)
+{
+ int ret = LPT_SCAN_CONTINUE;
+
+ /* Exclude LEBs that are currently in use */
+ if (lprops->flags & LPROPS_TAKEN)
+ return LPT_SCAN_CONTINUE;
+ /* Determine whether to add these LEB properties to the tree */
+ if (!in_tree && valuable(c, lprops))
+ ret |= LPT_SCAN_ADD;
+ /* Exclude index LEBS */
+ if (lprops->flags & LPROPS_INDEX)
+ return ret;
+ /* Exclude LEBs that cannot be made empty */
+ if (lprops->free + lprops->dirty != c->leb_size)
+ return ret;
+ /*
+ * We are allocating for the index so it is safe to allocate LEBs with
+ * only free and dirty space, because write buffers are sync'd at commit
+ * start.
+ */
+ data->lnum = lprops->lnum;
+ return LPT_SCAN_ADD | LPT_SCAN_STOP;
+}
+
+/**
+ * scan_for_leb_for_idx - scan for a free LEB for the index.
+ * @c: the UBIFS file-system description object
+ */
+static const struct ubifs_lprops *scan_for_leb_for_idx(struct ubifs_info *c)
+{
+ struct ubifs_lprops *lprops;
+ struct scan_data data;
+ int err;
+
+ data.lnum = -1;
+ err = ubifs_lpt_scan_nolock(c, -1, c->lscan_lnum,
+ (ubifs_lpt_scan_callback)scan_for_idx_cb,
+ &data);
+ if (err)
+ return ERR_PTR(err);
+ ubifs_assert(data.lnum >= c->main_first && data.lnum < c->leb_cnt);
+ c->lscan_lnum = data.lnum;
+ lprops = ubifs_lpt_lookup_dirty(c, data.lnum);
+ if (IS_ERR(lprops))
+ return lprops;
+ ubifs_assert(lprops->lnum == data.lnum);
+ ubifs_assert(lprops->free + lprops->dirty == c->leb_size);
+ ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
+ ubifs_assert(!(lprops->flags & LPROPS_INDEX));
+ return lprops;
+}
+
+/**
+ * ubifs_find_free_leb_for_idx - find a free LEB for the index.
+ * @c: the UBIFS file-system description object
+ *
+ * This function looks for a free LEB and returns that LEB number. The returned
+ * LEB is marked as "taken", "index".
+ *
+ * Only empty LEBs are allocated. This is for two reasons. First, the commit
+ * calculates the number of LEBs to allocate based on the assumption that they
+ * will be empty. Secondly, free space at the end of an index LEB is not
+ * guaranteed to be empty because it may have been used by the in-the-gaps
+ * method prior to an unclean unmount.
+ *
+ * If no LEB is found %-ENOSPC is returned. For other failures another negative
+ * error code is returned.
+ */
+int ubifs_find_free_leb_for_idx(struct ubifs_info *c)
+{
+ const struct ubifs_lprops *lprops;
+ int lnum = -1, err, flags;
+
+ ubifs_get_lprops(c);
+
+ lprops = ubifs_fast_find_empty(c);
+ if (!lprops) {
+ lprops = ubifs_fast_find_freeable(c);
+ if (!lprops) {
+ ubifs_assert(c->freeable_cnt == 0);
+ if (c->lst.empty_lebs - c->lst.taken_empty_lebs > 0) {
+ lprops = scan_for_leb_for_idx(c);
+ if (IS_ERR(lprops)) {
+ err = PTR_ERR(lprops);
+ goto out;
+ }
+ }
+ }
+ }
+
+ if (!lprops) {
+ err = -ENOSPC;
+ goto out;
+ }
+
+ lnum = lprops->lnum;
+
+ dbg_find("found LEB %d, free %d, dirty %d, flags %#x",
+ lnum, lprops->free, lprops->dirty, lprops->flags);
+
+ flags = lprops->flags | LPROPS_TAKEN | LPROPS_INDEX;
+ lprops = ubifs_change_lp(c, lprops, c->leb_size, 0, flags, 0);
+ if (IS_ERR(lprops)) {
+ err = PTR_ERR(lprops);
+ goto out;
+ }
+
+ ubifs_release_lprops(c);
+
+ /*
+ * Ensure that empty LEBs have been unmapped. They may not have been,
+ * for example, because of an unclean unmount. Also LEBs that were
+ * freeable LEBs (free + dirty == leb_size) will not have been unmapped.
+ */
+ err = ubifs_leb_unmap(c, lnum);
+ if (err) {
+ ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0,
+ LPROPS_TAKEN | LPROPS_INDEX, 0);
+ return err;
+ }
+
+ return lnum;
+
+out:
+ ubifs_release_lprops(c);
+ return err;
+}
+
+static int cmp_dirty_idx(const struct ubifs_lprops **a,
+ const struct ubifs_lprops **b)
+{
+ const struct ubifs_lprops *lpa = *a;
+ const struct ubifs_lprops *lpb = *b;
+
+ return lpa->dirty + lpa->free - lpb->dirty - lpb->free;
+}
+
+static void swap_dirty_idx(struct ubifs_lprops **a, struct ubifs_lprops **b,
+ int size)
+{
+ struct ubifs_lprops *t = *a;
+
+ *a = *b;
+ *b = t;
+}
+
+/**
+ * ubifs_save_dirty_idx_lnums - save an array of the most dirty index LEB nos.
+ * @c: the UBIFS file-system description object
+ *
+ * This function is called each commit to create an array of LEB numbers of
+ * dirty index LEBs sorted in order of dirty and free space. This is used by
+ * the in-the-gaps method of TNC commit.
+ */
+int ubifs_save_dirty_idx_lnums(struct ubifs_info *c)
+{
+ int i;
+
+ ubifs_get_lprops(c);
+ /* Copy the LPROPS_DIRTY_IDX heap */
+ c->dirty_idx.cnt = c->lpt_heap[LPROPS_DIRTY_IDX - 1].cnt;
+ memcpy(c->dirty_idx.arr, c->lpt_heap[LPROPS_DIRTY_IDX - 1].arr,
+ sizeof(void *) * c->dirty_idx.cnt);
+ /* Sort it so that the dirtiest is now at the end */
+ sort(c->dirty_idx.arr, c->dirty_idx.cnt, sizeof(void *),
+ (int (*)(const void *, const void *))cmp_dirty_idx,
+ (void (*)(void *, void *, int))swap_dirty_idx);
+ dbg_find("found %d dirty index LEBs", c->dirty_idx.cnt);
+ if (c->dirty_idx.cnt)
+ dbg_find("dirtiest index LEB is %d with dirty %d and free %d",
+ c->dirty_idx.arr[c->dirty_idx.cnt - 1]->lnum,
+ c->dirty_idx.arr[c->dirty_idx.cnt - 1]->dirty,
+ c->dirty_idx.arr[c->dirty_idx.cnt - 1]->free);
+ /* Replace the lprops pointers with LEB numbers */
+ for (i = 0; i < c->dirty_idx.cnt; i++)
+ c->dirty_idx.arr[i] = (void *)(size_t)c->dirty_idx.arr[i]->lnum;
+ ubifs_release_lprops(c);
+ return 0;
+}
+
+/**
+ * scan_dirty_idx_cb - callback used by the scan for a dirty index LEB.
+ * @c: the UBIFS file-system description object
+ * @lprops: LEB properties to scan
+ * @in_tree: whether the LEB properties are in main memory
+ * @data: information passed to and from the caller of the scan
+ *
+ * This function returns a code that indicates whether the scan should continue
+ * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree
+ * in main memory (%LPT_SCAN_ADD), or whether the scan should stop
+ * (%LPT_SCAN_STOP).
+ */
+static int scan_dirty_idx_cb(struct ubifs_info *c,
+ const struct ubifs_lprops *lprops, int in_tree,
+ struct scan_data *data)
+{
+ int ret = LPT_SCAN_CONTINUE;
+
+ /* Exclude LEBs that are currently in use */
+ if (lprops->flags & LPROPS_TAKEN)
+ return LPT_SCAN_CONTINUE;
+ /* Determine whether to add these LEB properties to the tree */
+ if (!in_tree && valuable(c, lprops))
+ ret |= LPT_SCAN_ADD;
+ /* Exclude non-index LEBs */
+ if (!(lprops->flags & LPROPS_INDEX))
+ return ret;
+ /* Exclude LEBs with too little space */
+ if (lprops->free + lprops->dirty < c->min_idx_node_sz)
+ return ret;
+ /* Finally we found space */
+ data->lnum = lprops->lnum;
+ return LPT_SCAN_ADD | LPT_SCAN_STOP;
+}
+
+/**
+ * find_dirty_idx_leb - find a dirty index LEB.
+ * @c: the UBIFS file-system description object
+ *
+ * This function returns LEB number upon success and a negative error code upon
+ * failure. In particular, -ENOSPC is returned if a dirty index LEB is not
+ * found.
+ *
+ * Note that this function scans the entire LPT but it is called very rarely.
+ */
+static int find_dirty_idx_leb(struct ubifs_info *c)
+{
+ const struct ubifs_lprops *lprops;
+ struct ubifs_lpt_heap *heap;
+ struct scan_data data;
+ int err, i, ret;
+
+ /* Check all structures in memory first */
+ data.lnum = -1;
+ heap = &c->lpt_heap[LPROPS_DIRTY_IDX - 1];
+ for (i = 0; i < heap->cnt; i++) {
+ lprops = heap->arr[i];
+ ret = scan_dirty_idx_cb(c, lprops, 1, &data);
+ if (ret & LPT_SCAN_STOP)
+ goto found;
+ }
+ list_for_each_entry(lprops, &c->frdi_idx_list, list) {
+ ret = scan_dirty_idx_cb(c, lprops, 1, &data);
+ if (ret & LPT_SCAN_STOP)
+ goto found;
+ }
+ list_for_each_entry(lprops, &c->uncat_list, list) {
+ ret = scan_dirty_idx_cb(c, lprops, 1, &data);
+ if (ret & LPT_SCAN_STOP)
+ goto found;
+ }
+ if (c->pnodes_have >= c->pnode_cnt)
+ /* All pnodes are in memory, so skip scan */
+ return -ENOSPC;
+ err = ubifs_lpt_scan_nolock(c, -1, c->lscan_lnum,
+ (ubifs_lpt_scan_callback)scan_dirty_idx_cb,
+ &data);
+ if (err)
+ return err;
+found:
+ ubifs_assert(data.lnum >= c->main_first && data.lnum < c->leb_cnt);
+ c->lscan_lnum = data.lnum;
+ lprops = ubifs_lpt_lookup_dirty(c, data.lnum);
+ if (IS_ERR(lprops))
+ return PTR_ERR(lprops);
+ ubifs_assert(lprops->lnum == data.lnum);
+ ubifs_assert(lprops->free + lprops->dirty >= c->min_idx_node_sz);
+ ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
+ ubifs_assert((lprops->flags & LPROPS_INDEX));
+
+ dbg_find("found dirty LEB %d, free %d, dirty %d, flags %#x",
+ lprops->lnum, lprops->free, lprops->dirty, lprops->flags);
+
+ lprops = ubifs_change_lp(c, lprops, LPROPS_NC, LPROPS_NC,
+ lprops->flags | LPROPS_TAKEN, 0);
+ if (IS_ERR(lprops))
+ return PTR_ERR(lprops);
+
+ return lprops->lnum;
+}
+
+/**
+ * get_idx_gc_leb - try to get a LEB number from trivial GC.
+ * @c: the UBIFS file-system description object
+ */
+static int get_idx_gc_leb(struct ubifs_info *c)
+{
+ const struct ubifs_lprops *lp;
+ int err, lnum;
+
+ err = ubifs_get_idx_gc_leb(c);
+ if (err < 0)
+ return err;
+ lnum = err;
+ /*
+ * The LEB was due to be unmapped after the commit but
+ * it is needed now for this commit.
+ */
+ lp = ubifs_lpt_lookup_dirty(c, lnum);
+ if (unlikely(IS_ERR(lp)))
+ return PTR_ERR(lp);
+ lp = ubifs_change_lp(c, lp, LPROPS_NC, LPROPS_NC,
+ lp->flags | LPROPS_INDEX, -1);
+ if (unlikely(IS_ERR(lp)))
+ return PTR_ERR(lp);
+ dbg_find("LEB %d, dirty %d and free %d flags %#x",
+ lp->lnum, lp->dirty, lp->free, lp->flags);
+ return lnum;
+}
+
+/**
+ * find_dirtiest_idx_leb - find dirtiest index LEB from dirtiest array.
+ * @c: the UBIFS file-system description object
+ */
+static int find_dirtiest_idx_leb(struct ubifs_info *c)
+{
+ const struct ubifs_lprops *lp;
+ int lnum;
+
+ while (1) {
+ if (!c->dirty_idx.cnt)
+ return -ENOSPC;
+ /* The lprops pointers were replaced by LEB numbers */
+ lnum = (size_t)c->dirty_idx.arr[--c->dirty_idx.cnt];
+ lp = ubifs_lpt_lookup(c, lnum);
+ if (IS_ERR(lp))
+ return PTR_ERR(lp);
+ if ((lp->flags & LPROPS_TAKEN) || !(lp->flags & LPROPS_INDEX))
+ continue;
+ lp = ubifs_change_lp(c, lp, LPROPS_NC, LPROPS_NC,
+ lp->flags | LPROPS_TAKEN, 0);
+ if (IS_ERR(lp))
+ return PTR_ERR(lp);
+ break;
+ }
+ dbg_find("LEB %d, dirty %d and free %d flags %#x", lp->lnum, lp->dirty,
+ lp->free, lp->flags);
+ ubifs_assert(lp->flags | LPROPS_TAKEN);
+ ubifs_assert(lp->flags | LPROPS_INDEX);
+ return lnum;
+}
+
+/**
+ * ubifs_find_dirty_idx_leb - try to find dirtiest index LEB as at last commit.
+ * @c: the UBIFS file-system description object
+ *
+ * This function attempts to find an untaken index LEB with the most free and
+ * dirty space that can be used without overwriting index nodes that were in the
+ * last index committed.
+ */
+int ubifs_find_dirty_idx_leb(struct ubifs_info *c)
+{
+ int err;
+
+ ubifs_get_lprops(c);
+
+ /*
+ * We made an array of the dirtiest index LEB numbers as at the start of
+ * last commit. Try that array first.
+ */
+ err = find_dirtiest_idx_leb(c);
+
+ /* Next try scanning the entire LPT */
+ if (err == -ENOSPC)
+ err = find_dirty_idx_leb(c);
+
+ /* Finally take any index LEBs awaiting trivial GC */
+ if (err == -ENOSPC)
+ err = get_idx_gc_leb(c);
+
+ ubifs_release_lprops(c);
+ return err;
+}
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ * Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file implements garbage collection. The procedure for garbage collection
+ * is different depending on whether a LEB as an index LEB (contains index
+ * nodes) or not. For non-index LEBs, garbage collection finds a LEB which
+ * contains a lot of dirty space (obsolete nodes), and copies the non-obsolete
+ * nodes to the journal, at which point the garbage-collected LEB is free to be
+ * reused. For index LEBs, garbage collection marks the non-obsolete index nodes
+ * dirty in the TNC, and after the next commit, the garbage-collected LEB is
+ * to be reused. Garbage collection will cause the number of dirty index nodes
+ * to grow, however sufficient space is reserved for the index to ensure the
+ * commit will never run out of space.
+ */
+
+#include <linux/pagemap.h>
+#include "ubifs.h"
+
+/*
+ * GC tries to optimize the way it fit nodes to available space, and it sorts
+ * nodes a little. The below constants are watermarks which define "large",
+ * "medium", and "small" nodes.
+ */
+#define MEDIUM_NODE_WM (UBIFS_BLOCK_SIZE / 4)
+#define SMALL_NODE_WM UBIFS_MAX_DENT_NODE_SZ
+
+/*
+ * GC may need to move more then one LEB to make progress. The below constants
+ * define "soft" and "hard" limits on the number of LEBs the garbage collector
+ * may move.
+ */
+#define SOFT_LEBS_LIMIT 4
+#define HARD_LEBS_LIMIT 32
+
+/**
+ * switch_gc_head - switch the garbage collection journal head.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to write
+ * @len: length of the buffer to write
+ * @lnum: LEB number written is returned here
+ * @offs: offset written is returned here
+ *
+ * This function switch the GC head to the next LEB which is reserved in
+ * @c->gc_lnum. Returns %0 in case of success, %-EAGAIN if commit is required,
+ * and other negative error code in case of failures.
+ */
+static int switch_gc_head(struct ubifs_info *c)
+{
+ int err, gc_lnum = c->gc_lnum;
+ struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf;
+
+ ubifs_assert(gc_lnum != -1);
+ dbg_gc("switch GC head from LEB %d:%d to LEB %d (waste %d bytes)",
+ wbuf->lnum, wbuf->offs + wbuf->used, gc_lnum,
+ c->leb_size - wbuf->offs - wbuf->used);
+
+ err = ubifs_wbuf_sync_nolock(wbuf);
+ if (err)
+ return err;
+
+ /*
+ * The GC write-buffer was synchronized, we may safely unmap
+ * 'c->gc_lnum'.
+ */
+ err = ubifs_leb_unmap(c, gc_lnum);
+ if (err)
+ return err;
+
+ err = ubifs_add_bud_to_log(c, GCHD, gc_lnum, 0);
+ if (err)
+ return err;
+
+ c->gc_lnum = -1;
+ err = ubifs_wbuf_seek_nolock(wbuf, gc_lnum, 0, UBI_LONGTERM);
+ return err;
+}
+
+/**
+ * move_nodes - move nodes.
+ * @c: UBIFS file-system description object
+ * @sleb: describes nodes to move
+ *
+ * This function moves valid nodes from data LEB described by @sleb to the GC
+ * journal head. The obsolete nodes are dropped.
+ *
+ * When moving nodes we have to deal with classical bin-packing problem: the
+ * space in the current GC journal head LEB and in @c->gc_lnum are the "bins",
+ * where the nodes in the @sleb->nodes list are the elements which should be
+ * fit optimally to the bins. This function uses the "first fit decreasing"
+ * strategy, although it does not really sort the nodes but just split them on
+ * 3 classes - large, medium, and small, so they are roughly sorted.
+ *
+ * This function returns zero in case of success, %-EAGAIN if commit is
+ * required, and other negative error codes in case of other failures.
+ */
+static int move_nodes(struct ubifs_info *c, struct ubifs_scan_leb *sleb)
+{
+ struct ubifs_scan_node *snod, *tmp;
+ struct list_head large, medium, small;
+ struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf;
+ int avail, err, min = INT_MAX;
+
+ INIT_LIST_HEAD(&large);
+ INIT_LIST_HEAD(&medium);
+ INIT_LIST_HEAD(&small);
+
+ list_for_each_entry_safe(snod, tmp, &sleb->nodes, list) {
+ struct list_head *lst;
+
+ ubifs_assert(snod->type != UBIFS_IDX_NODE);
+ ubifs_assert(snod->type != UBIFS_REF_NODE);
+ ubifs_assert(snod->type != UBIFS_CS_NODE);
+
+ err = ubifs_tnc_has_node(c, &snod->key, 0, sleb->lnum,
+ snod->offs, 0);
+ if (err < 0)
+ goto out;
+
+ lst = &snod->list;
+ list_del(lst);
+ if (!err) {
+ /* The node is obsolete, remove it from the list */
+ kfree(snod);
+ continue;
+ }
+
+ /*
+ * Sort the list of nodes so that large nodes go first, and
+ * small nodes go last.
+ */
+ if (snod->len > MEDIUM_NODE_WM)
+ list_add(lst, &large);
+ else if (snod->len > SMALL_NODE_WM)
+ list_add(lst, &medium);
+ else
+ list_add(lst, &small);
+
+ /* And find the smallest node */
+ if (snod->len < min)
+ min = snod->len;
+ }
+
+ /*
+ * Join the tree lists so that we'd have one roughly sorted list
+ * ('large' will be the head of the joined list).
+ */
+ list_splice(&medium, large.prev);
+ list_splice(&small, large.prev);
+
+ if (wbuf->lnum == -1) {
+ /*
+ * The GC journal head is not set, because it is the first GC
+ * invocation since mount.
+ */
+ err = switch_gc_head(c);
+ if (err)
+ goto out;
+ }
+
+ /* Write nodes to their new location. Use the first-fit strategy */
+ while (1) {
+ avail = c->leb_size - wbuf->offs - wbuf->used;
+ list_for_each_entry_safe(snod, tmp, &large, list) {
+ int new_lnum, new_offs;
+
+ if (avail < min)
+ break;
+
+ if (snod->len > avail)
+ /* This node does not fit */
+ continue;
+
+ cond_resched();
+
+ new_lnum = wbuf->lnum;
+ new_offs = wbuf->offs + wbuf->used;
+ err = ubifs_wbuf_write_nolock(wbuf, snod->node,
+ snod->len);
+ if (err)
+ goto out;
+ err = ubifs_tnc_replace(c, &snod->key, sleb->lnum,
+ snod->offs, new_lnum, new_offs,
+ snod->len);
+ if (err)
+ goto out;
+
+ avail = c->leb_size - wbuf->offs - wbuf->used;
+ list_del(&snod->list);
+ kfree(snod);
+ }
+
+ if (list_empty(&large))
+ break;
+
+ /*
+ * Waste the rest of the space in the LEB and switch to the
+ * next LEB.
+ */
+ err = switch_gc_head(c);
+ if (err)
+ goto out;
+ }
+
+ return 0;
+
+out:
+ list_for_each_entry_safe(snod, tmp, &large, list) {
+ list_del(&snod->list);
+ kfree(snod);
+ }
+ return err;
+}
+
+/**
+ * gc_sync_wbufs - sync write-buffers for GC.
+ * @c: UBIFS file-system description object
+ *
+ * We must guarantee that obsoleting nodes are on flash. Unfortunately they may
+ * be in a write-buffer instead. That is, a node could be written to a
+ * write-buffer, obsoleting another node in a LEB that is GC'd. If that LEB is
+ * erased before the write-buffer is sync'd and then there is an unclean
+ * unmount, then an existing node is lost. To avoid this, we sync all
+ * write-buffers.
+ *
+ * This function returns %0 on success or a negative error code on failure.
+ */
+static int gc_sync_wbufs(struct ubifs_info *c)
+{
+ int err, i;
+
+ for (i = 0; i < c->jhead_cnt; i++) {
+ if (i == GCHD)
+ continue;
+ err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
+ if (err)
+ return err;
+ }
+ return 0;
+}
+
+/**
+ * ubifs_garbage_collect_leb - garbage-collect a logical eraseblock.
+ * @c: UBIFS file-system description object
+ * @lp: describes the LEB to garbage collect
+ *
+ * This function garbage-collects an LEB and returns one of the @LEB_FREED,
+ * @LEB_RETAINED, etc positive codes in case of success, %-EAGAIN if commit is
+ * required, and other negative error codes in case of failures.
+ */
+int ubifs_garbage_collect_leb(struct ubifs_info *c, struct ubifs_lprops *lp)
+{
+ struct ubifs_scan_leb *sleb;
+ struct ubifs_scan_node *snod;
+ struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf;
+ int err = 0, lnum = lp->lnum;
+
+ ubifs_assert(c->gc_lnum != -1 || wbuf->offs + wbuf->used == 0 ||
+ c->need_recovery);
+ ubifs_assert(c->gc_lnum != lnum);
+ ubifs_assert(wbuf->lnum != lnum);
+
+ /*
+ * We scan the entire LEB even though we only really need to scan up to
+ * (c->leb_size - lp->free).
+ */
+ sleb = ubifs_scan(c, lnum, 0, c->sbuf);
+ if (IS_ERR(sleb))
+ return PTR_ERR(sleb);
+
+ ubifs_assert(!list_empty(&sleb->nodes));
+ snod = list_entry(sleb->nodes.next, struct ubifs_scan_node, list);
+
+ if (snod->type == UBIFS_IDX_NODE) {
+ struct ubifs_gced_idx_leb *idx_gc;
+
+ dbg_gc("indexing LEB %d (free %d, dirty %d)",
+ lnum, lp->free, lp->dirty);
+ list_for_each_entry(snod, &sleb->nodes, list) {
+ struct ubifs_idx_node *idx = snod->node;
+ int level = le16_to_cpu(idx->level);
+
+ ubifs_assert(snod->type == UBIFS_IDX_NODE);
+ key_read(c, ubifs_idx_key(c, idx), &snod->key);
+ err = ubifs_dirty_idx_node(c, &snod->key, level, lnum,
+ snod->offs);
+ if (err)
+ goto out;
+ }
+
+ idx_gc = kmalloc(sizeof(struct ubifs_gced_idx_leb), GFP_NOFS);
+ if (!idx_gc) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ idx_gc->lnum = lnum;
+ idx_gc->unmap = 0;
+ list_add(&idx_gc->list, &c->idx_gc);
+
+ /*
+ * Don't release the LEB until after the next commit, because
+ * it may contain date which is needed for recovery. So
+ * although we freed this LEB, it will become usable only after
+ * the commit.
+ */
+ err = ubifs_change_one_lp(c, lnum, c->leb_size, 0, 0,
+ LPROPS_INDEX, 1);
+ if (err)
+ goto out;
+ err = LEB_FREED_IDX;
+ } else {
+ dbg_gc("data LEB %d (free %d, dirty %d)",
+ lnum, lp->free, lp->dirty);
+
+ err = move_nodes(c, sleb);
+ if (err)
+ goto out;
+
+ err = gc_sync_wbufs(c);
+ if (err)
+ goto out;
+
+ err = ubifs_change_one_lp(c, lnum, c->leb_size, 0, 0, 0, 0);
+ if (err)
+ goto out;
+
+ if (c->gc_lnum == -1) {
+ c->gc_lnum = lnum;
+ err = LEB_RETAINED;
+ } else {
+ err = ubifs_wbuf_sync_nolock(wbuf);
+ if (err)
+ goto out;
+
+ err = ubifs_leb_unmap(c, lnum);
+ if (err)
+ goto out;
+
+ err = LEB_FREED;
+ }
+ }
+
+out:
+ ubifs_scan_destroy(sleb);
+ return err;
+}
+
+/**
+ * ubifs_garbage_collect - UBIFS garbage collector.
+ * @c: UBIFS file-system description object
+ * @anyway: do GC even if there are free LEBs
+ *
+ * This function does out-of-place garbage collection. The return codes are:
+ * o positive LEB number if the LEB has been freed and may be used;
+ * o %-EAGAIN if the caller has to run commit;
+ * o %-ENOSPC if GC failed to make any progress;
+ * o other negative error codes in case of other errors.
+ *
+ * Garbage collector writes data to the journal when GC'ing data LEBs, and just
+ * marking indexing nodes dirty when GC'ing indexing LEBs. Thus, at some point
+ * commit may be required. But commit cannot be run from inside GC, because the
+ * caller might be holding the commit lock, so %-EAGAIN is returned instead;
+ * And this error code means that the caller has to run commit, and re-run GC
+ * if there is still no free space.
+ *
+ * There are many reasons why this function may return %-EAGAIN:
+ * o the log is full and there is no space to write an LEB reference for
+ * @c->gc_lnum;
+ * o the journal is too large and exceeds size limitations;
+ * o GC moved indexing LEBs, but they can be used only after the commit;
+ * o the shrinker fails to find clean znodes to free and requests the commit;
+ * o etc.
+ *
+ * Note, if the file-system is close to be full, this function may return
+ * %-EAGAIN infinitely, so the caller has to limit amount of re-invocations of
+ * the function. E.g., this happens if the limits on the journal size are too
+ * tough and GC writes too much to the journal before an LEB is freed. This
+ * might also mean that the journal is too large, and the TNC becomes to big,
+ * so that the shrinker is constantly called, finds not clean znodes to free,
+ * and requests commit. Well, this may also happen if the journal is all right,
+ * but another kernel process consumes too much memory. Anyway, infinite
+ * %-EAGAIN may happen, but in some extreme/misconfiguration cases.
+ */
+int ubifs_garbage_collect(struct ubifs_info *c, int anyway)
+{
+ int i, err, ret, min_space = c->dead_wm;
+ struct ubifs_lprops lp;
+ struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf;
+
+ ubifs_assert_cmt_locked(c);
+
+ if (ubifs_gc_should_commit(c))
+ return -EAGAIN;
+
+ mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
+
+ if (c->ro_media) {
+ ret = -EROFS;
+ goto out_unlock;
+ }
+
+ /* We expect the write-buffer to be empty on entry */
+ ubifs_assert(!wbuf->used);
+
+ for (i = 0; ; i++) {
+ int space_before = c->leb_size - wbuf->offs - wbuf->used;
+ int space_after;
+
+ cond_resched();
+
+ /* Give the commit an opportunity to run */
+ if (ubifs_gc_should_commit(c)) {
+ ret = -EAGAIN;
+ break;
+ }
+
+ if (i > SOFT_LEBS_LIMIT && !list_empty(&c->idx_gc)) {
+ /*
+ * We've done enough iterations. Indexing LEBs were
+ * moved and will be available after the commit.
+ */
+ dbg_gc("soft limit, some index LEBs GC'ed, -EAGAIN");
+ ubifs_commit_required(c);
+ ret = -EAGAIN;
+ break;
+ }
+
+ if (i > HARD_LEBS_LIMIT) {
+ /*
+ * We've moved too many LEBs and have not made
+ * progress, give up.
+ */
+ dbg_gc("hard limit, -ENOSPC");
+ ret = -ENOSPC;
+ break;
+ }
+
+ /*
+ * Empty and freeable LEBs can turn up while we waited for
+ * the wbuf lock, or while we have been running GC. In that
+ * case, we should just return one of those instead of
+ * continuing to GC dirty LEBs. Hence we request
+ * 'ubifs_find_dirty_leb()' to return an empty LEB if it can.
+ */
+ ret = ubifs_find_dirty_leb(c, &lp, min_space, anyway ? 0 : 1);
+ if (ret) {
+ if (ret == -ENOSPC)
+ dbg_gc("no more dirty LEBs");
+ break;
+ }
+
+ dbg_gc("found LEB %d: free %d, dirty %d, sum %d "
+ "(min. space %d)", lp.lnum, lp.free, lp.dirty,
+ lp.free + lp.dirty, min_space);
+
+ if (lp.free + lp.dirty == c->leb_size) {
+ /* An empty LEB was returned */
+ dbg_gc("LEB %d is free, return it", lp.lnum);
+ /*
+ * ubifs_find_dirty_leb() doesn't return freeable index
+ * LEBs.
+ */
+ ubifs_assert(!(lp.flags & LPROPS_INDEX));
+ if (lp.free != c->leb_size) {
+ /*
+ * Write buffers must be sync'd before
+ * unmapping freeable LEBs, because one of them
+ * may contain data which obsoletes something
+ * in 'lp.pnum'.
+ */
+ ret = gc_sync_wbufs(c);
+ if (ret)
+ goto out;
+ ret = ubifs_change_one_lp(c, lp.lnum,
+ c->leb_size, 0, 0, 0,
+ 0);
+ if (ret)
+ goto out;
+ }
+ ret = ubifs_leb_unmap(c, lp.lnum);
+ if (ret)
+ goto out;
+ ret = lp.lnum;
+ break;
+ }
+
+ space_before = c->leb_size - wbuf->offs - wbuf->used;
+ if (wbuf->lnum == -1)
+ space_before = 0;
+
+ ret = ubifs_garbage_collect_leb(c, &lp);
+ if (ret < 0) {
+ if (ret == -EAGAIN || ret == -ENOSPC) {
+ /*
+ * These codes are not errors, so we have to
+ * return the LEB to lprops. But if the
+ * 'ubifs_return_leb()' function fails, its
+ * failure code is propagated to the caller
+ * instead of the original '-EAGAIN' or
+ * '-ENOSPC'.
+ */
+ err = ubifs_return_leb(c, lp.lnum);
+ if (err)
+ ret = err;
+ break;
+ }
+ goto out;
+ }
+
+ if (ret == LEB_FREED) {
+ /* An LEB has been freed and is ready for use */
+ dbg_gc("LEB %d freed, return", lp.lnum);
+ ret = lp.lnum;
+ break;
+ }
+
+ if (ret == LEB_FREED_IDX) {
+ /*
+ * This was an indexing LEB and it cannot be
+ * immediately used. And instead of requesting the
+ * commit straight away, we try to garbage collect some
+ * more.
+ */
+ dbg_gc("indexing LEB %d freed, continue", lp.lnum);
+ continue;
+ }
+
+ ubifs_assert(ret == LEB_RETAINED);
+ space_after = c->leb_size - wbuf->offs - wbuf->used;
+ dbg_gc("LEB %d retained, freed %d bytes", lp.lnum,
+ space_after - space_before);
+
+ if (space_after > space_before) {
+ /* GC makes progress, keep working */
+ min_space >>= 1;
+ if (min_space < c->dead_wm)
+ min_space = c->dead_wm;
+ continue;
+ }
+
+ dbg_gc("did not make progress");
+
+ /*
+ * GC moved an LEB bud have not done any progress. This means
+ * that the previous GC head LEB contained too few free space
+ * and the LEB which was GC'ed contained only large nodes which
+ * did not fit that space.
+ *
+ * We can do 2 things:
+ * 1. pick another LEB in a hope it'll contain a small node
+ * which will fit the space we have at the end of current GC
+ * head LEB, but there is no guarantee, so we try this out
+ * unless we have already been working for too long;
+ * 2. request an LEB with more dirty space, which will force
+ * 'ubifs_find_dirty_leb()' to start scanning the lprops
+ * table, instead of just picking one from the heap
+ * (previously it already picked the dirtiest LEB).
+ */
+ if (i < SOFT_LEBS_LIMIT) {
+ dbg_gc("try again");
+ continue;
+ }
+
+ min_space <<= 1;
+ if (min_space > c->dark_wm)
+ min_space = c->dark_wm;
+ dbg_gc("set min. space to %d", min_space);
+ }
+
+ if (ret == -ENOSPC && !list_empty(&c->idx_gc)) {
+ dbg_gc("no space, some index LEBs GC'ed, -EAGAIN");
+ ubifs_commit_required(c);
+ ret = -EAGAIN;
+ }
+
+ err = ubifs_wbuf_sync_nolock(wbuf);
+ if (!err)
+ err = ubifs_leb_unmap(c, c->gc_lnum);
+ if (err) {
+ ret = err;
+ goto out;
+ }
+out_unlock:
+ mutex_unlock(&wbuf->io_mutex);
+ return ret;
+
+out:
+ ubifs_assert(ret < 0);
+ ubifs_assert(ret != -ENOSPC && ret != -EAGAIN);
+ ubifs_ro_mode(c, ret);
+ ubifs_wbuf_sync_nolock(wbuf);
+ mutex_unlock(&wbuf->io_mutex);
+ ubifs_return_leb(c, lp.lnum);
+ return ret;
+}
+
+/**
+ * ubifs_gc_start_commit - garbage collection at start of commit.
+ * @c: UBIFS file-system description object
+ *
+ * If a LEB has only dirty and free space, then we may safely unmap it and make
+ * it free. Note, we cannot do this with indexing LEBs because dirty space may
+ * correspond index nodes that are required for recovery. In that case, the
+ * LEB cannot be unmapped until after the next commit.
+ *
+ * This function returns %0 upon success and a negative error code upon failure.
+ */
+int ubifs_gc_start_commit(struct ubifs_info *c)
+{
+ struct ubifs_gced_idx_leb *idx_gc;
+ const struct ubifs_lprops *lp;
+ int err = 0, flags;
+
+ ubifs_get_lprops(c);
+
+ /*
+ * Unmap (non-index) freeable LEBs. Note that recovery requires that all
+ * wbufs are sync'd before this, which is done in 'do_commit()'.
+ */
+ while (1) {
+ lp = ubifs_fast_find_freeable(c);
+ if (unlikely(IS_ERR(lp))) {
+ err = PTR_ERR(lp);
+ goto out;
+ }
+ if (!lp)
+ break;
+ ubifs_assert(!(lp->flags & LPROPS_TAKEN));
+ ubifs_assert(!(lp->flags & LPROPS_INDEX));
+ err = ubifs_leb_unmap(c, lp->lnum);
+ if (err)
+ goto out;
+ lp = ubifs_change_lp(c, lp, c->leb_size, 0, lp->flags, 0);
+ if (unlikely(IS_ERR(lp))) {
+ err = PTR_ERR(lp);
+ goto out;
+ }
+ ubifs_assert(!(lp->flags & LPROPS_TAKEN));
+ ubifs_assert(!(lp->flags & LPROPS_INDEX));
+ }
+
+ /* Mark GC'd index LEBs OK to unmap after this commit finishes */
+ list_for_each_entry(idx_gc, &c->idx_gc, list)
+ idx_gc->unmap = 1;
+
+ /* Record index freeable LEBs for unmapping after commit */
+ while (1) {
+ lp = ubifs_fast_find_frdi_idx(c);
+ if (unlikely(IS_ERR(lp))) {
+ err = PTR_ERR(lp);
+ goto out;
+ }
+ if (!lp)
+ break;
+ idx_gc = kmalloc(sizeof(struct ubifs_gced_idx_leb), GFP_NOFS);
+ if (!idx_gc) {
+ err = -ENOMEM;
+ goto out;
+ }
+ ubifs_assert(!(lp->flags & LPROPS_TAKEN));
+ ubifs_assert(lp->flags & LPROPS_INDEX);
+ /* Don't release the LEB until after the next commit */
+ flags = (lp->flags | LPROPS_TAKEN) ^ LPROPS_INDEX;
+ lp = ubifs_change_lp(c, lp, c->leb_size, 0, flags, 1);
+ if (unlikely(IS_ERR(lp))) {
+ err = PTR_ERR(lp);
+ kfree(idx_gc);
+ goto out;
+ }
+ ubifs_assert(lp->flags & LPROPS_TAKEN);
+ ubifs_assert(!(lp->flags & LPROPS_INDEX));
+ idx_gc->lnum = lp->lnum;
+ idx_gc->unmap = 1;
+ list_add(&idx_gc->list, &c->idx_gc);
+ }
+out:
+ ubifs_release_lprops(c);
+ return err;
+}
+
+/**
+ * ubifs_gc_end_commit - garbage collection at end of commit.
+ * @c: UBIFS file-system description object
+ *
+ * This function completes out-of-place garbage collection of index LEBs.
+ */
+int ubifs_gc_end_commit(struct ubifs_info *c)
+{
+ struct ubifs_gced_idx_leb *idx_gc, *tmp;
+ struct ubifs_wbuf *wbuf;
+ int err = 0;
+
+ wbuf = &c->jheads[GCHD].wbuf;
+ mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
+ list_for_each_entry_safe(idx_gc, tmp, &c->idx_gc, list)
+ if (idx_gc->unmap) {
+ dbg_gc("LEB %d", idx_gc->lnum);
+ err = ubifs_leb_unmap(c, idx_gc->lnum);
+ if (err)
+ goto out;
+ err = ubifs_change_one_lp(c, idx_gc->lnum, LPROPS_NC,
+ LPROPS_NC, 0, LPROPS_TAKEN, -1);
+ if (err)
+ goto out;
+ list_del(&idx_gc->list);
+ kfree(idx_gc);
+ }
+out:
+ mutex_unlock(&wbuf->io_mutex);
+ return err;
+}
+
+/**
+ * ubifs_destroy_idx_gc - destroy idx_gc list.
+ * @c: UBIFS file-system description object
+ *
+ * This function destroys the idx_gc list. It is called when unmounting or
+ * remounting read-only so locks are not needed.
+ */
+void ubifs_destroy_idx_gc(struct ubifs_info *c)
+{
+ while (!list_empty(&c->idx_gc)) {
+ struct ubifs_gced_idx_leb *idx_gc;
+
+ idx_gc = list_entry(c->idx_gc.next, struct ubifs_gced_idx_leb,
+ list);
+ c->idx_gc_cnt -= 1;
+ list_del(&idx_gc->list);
+ kfree(idx_gc);
+ }
+
+}
+
+/**
+ * ubifs_get_idx_gc_leb - get a LEB from GC'd index LEB list.
+ * @c: UBIFS file-system description object
+ *
+ * Called during start commit so locks are not needed.
+ */
+int ubifs_get_idx_gc_leb(struct ubifs_info *c)
+{
+ struct ubifs_gced_idx_leb *idx_gc;
+ int lnum;
+
+ if (list_empty(&c->idx_gc))
+ return -ENOSPC;
+ idx_gc = list_entry(c->idx_gc.next, struct ubifs_gced_idx_leb, list);
+ lnum = idx_gc->lnum;
+ /* c->idx_gc_cnt is updated by the caller when lprops are updated */
+ list_del(&idx_gc->list);
+ kfree(idx_gc);
+ return lnum;
+}
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ * Copyright (C) 2006, 2007 University of Szeged, Hungary
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ * Adrian Hunter
+ * Zoltan Sogor
+ */
+
+/*
+ * This file implements UBIFS I/O subsystem which provides various I/O-related
+ * helper functions (reading/writing/checking/validating nodes) and implements
+ * write-buffering support. Write buffers help to save space which otherwise
+ * would have been wasted for padding to the nearest minimal I/O unit boundary.
+ * Instead, data first goes to the write-buffer and is flushed when the
+ * buffer is full or when it is not used for some time (by timer). This is
+ * similarto the mechanism is used by JFFS2.
+ *
+ * Write-buffers are defined by 'struct ubifs_wbuf' objects and protected by
+ * mutexes defined inside these objects. Since sometimes upper-level code
+ * has to lock the write-buffer (e.g. journal space reservation code), many
+ * functions related to write-buffers have "nolock" suffix which means that the
+ * caller has to lock the write-buffer before calling this function.
+ *
+ * UBIFS stores nodes at 64 bit-aligned addresses. If the node length is not
+ * aligned, UBIFS starts the next node from the aligned address, and the padded
+ * bytes may contain any rubbish. In other words, UBIFS does not put padding
+ * bytes in those small gaps. Common headers of nodes store real node lengths,
+ * not aligned lengths. Indexing nodes also store real lengths in branches.
+ *
+ * UBIFS uses padding when it pads to the next min. I/O unit. In this case it
+ * uses padding nodes or padding bytes, if the padding node does not fit.
+ *
+ * All UBIFS nodes are protected by CRC checksums and UBIFS checks all nodes
+ * every time they are read from the flash media.
+ */
+
+#include <linux/crc32.h>
+#include "ubifs.h"
+
+/**
+ * ubifs_check_node - check node.
+ * @c: UBIFS file-system description object
+ * @buf: node to check
+ * @lnum: logical eraseblock number
+ * @offs: offset within the logical eraseblock
+ * @quiet: print no messages
+ *
+ * This function checks node magic number and CRC checksum. This function also
+ * validates node length to prevent UBIFS from becoming crazy when an attacker
+ * feeds it a file-system image with incorrect nodes. For example, too large
+ * node length in the common header could cause UBIFS to read memory outside of
+ * allocated buffer when checking the CRC checksum.
+ *
+ * This function returns zero in case of success %-EUCLEAN in case of bad CRC
+ * or magic.
+ */
+int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum,
+ int offs, int quiet)
+{
+ int err = -EINVAL, type, node_len;
+ uint32_t crc, node_crc, magic;
+ const struct ubifs_ch *ch = buf;
+
+ ubifs_assert(lnum >= 0 && lnum < c->leb_cnt && offs >= 0);
+ ubifs_assert(!(offs & 7) && offs < c->leb_size);
+
+ magic = le32_to_cpu(ch->magic);
+ if (magic != UBIFS_NODE_MAGIC) {
+ if (!quiet)
+ ubifs_err("bad magic %#08x, expected %#08x",
+ magic, UBIFS_NODE_MAGIC);
+ err = -EUCLEAN;
+ goto out;
+ }
+
+ type = ch->node_type;
+ if (type < 0 || type >= UBIFS_NODE_TYPES_CNT) {
+ if (!quiet)
+ ubifs_err("bad node type %d", type);
+ goto out;
+ }
+
+ node_len = le32_to_cpu(ch->len);
+ if (node_len + offs > c->leb_size)
+ goto out_len;
+
+ if (c->ranges[type].max_len == 0) {
+ if (node_len != c->ranges[type].len)
+ goto out_len;
+ } else if (node_len < c->ranges[type].min_len ||
+ node_len > c->ranges[type].max_len)
+ goto out_len;
+
+ crc = crc32(UBIFS_CRC32_INIT, buf + 8, node_len - 8);
+ node_crc = le32_to_cpu(ch->crc);
+ if (crc != node_crc) {
+ if (!quiet)
+ ubifs_err("bad CRC: calculated %#08x, read %#08x",
+ crc, node_crc);
+ err = -EUCLEAN;
+ goto out;
+ }
+
+ return 0;
+
+out_len:
+ if (!quiet)
+ ubifs_err("bad node length %d", node_len);
+out:
+ if (!quiet) {
+ ubifs_err("bad node at LEB %d:%d", lnum, offs);
+ dbg_dump_node(c, buf);
+ dbg_dump_stack();
+ }
+ return err;
+}
+
+/**
+ * ubifs_pad - pad flash space.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to put padding to
+ * @pad: how many bytes to pad
+ *
+ * The flash media obliges us to write only in chunks of %c->min_io_size and
+ * when we have to write less data we add padding node to the write-buffer and
+ * pad it to the next minimal I/O unit's boundary. Padding nodes help when the
+ * media is being scanned. If the amount of wasted space is not enough to fit a
+ * padding node which takes %UBIFS_PAD_NODE_SZ bytes, we write padding bytes
+ * pattern (%UBIFS_PADDING_BYTE).
+ *
+ * Padding nodes are also used to fill gaps when the "commit-in-gaps" method is
+ * used.
+ */
+void ubifs_pad(const struct ubifs_info *c, void *buf, int pad)
+{
+ uint32_t crc;
+
+ ubifs_assert(pad >= 0 && !(pad & 7));
+
+ if (pad >= UBIFS_PAD_NODE_SZ) {
+ struct ubifs_ch *ch = buf;
+ struct ubifs_pad_node *pad_node = buf;
+
+ ch->magic = cpu_to_le32(UBIFS_NODE_MAGIC);
+ ch->node_type = UBIFS_PAD_NODE;
+ ch->group_type = UBIFS_NO_NODE_GROUP;
+ ch->padding[0] = ch->padding[1] = 0;
+ ch->sqnum = 0;
+ ch->len = cpu_to_le32(UBIFS_PAD_NODE_SZ);
+ pad -= UBIFS_PAD_NODE_SZ;
+ pad_node->pad_len = cpu_to_le32(pad);
+ crc = crc32(UBIFS_CRC32_INIT, buf + 8, UBIFS_PAD_NODE_SZ - 8);
+ ch->crc = cpu_to_le32(crc);
+ memset(buf + UBIFS_PAD_NODE_SZ, 0, pad);
+ } else if (pad > 0)
+ /* Too little space, padding node won't fit */
+ memset(buf, UBIFS_PADDING_BYTE, pad);
+}
+
+/**
+ * next_sqnum - get next sequence number.
+ * @c: UBIFS file-system description object
+ */
+static unsigned long long next_sqnum(struct ubifs_info *c)
+{
+ unsigned long long sqnum;
+
+ spin_lock(&c->cnt_lock);
+ sqnum = ++c->max_sqnum;
+ spin_unlock(&c->cnt_lock);
+
+ if (unlikely(sqnum >= SQNUM_WARN_WATERMARK)) {
+ if (sqnum >= SQNUM_WATERMARK) {
+ ubifs_err("sequence number overflow %llu, end of life",
+ sqnum);
+ ubifs_ro_mode(c, -EINVAL);
+ }
+ ubifs_warn("running out of sequence numbers, end of life soon");
+ }
+
+ return sqnum;
+}
+
+/**
+ * ubifs_prepare_node - prepare node to be written to flash.
+ * @c: UBIFS file-system description object
+ * @node: the node to pad
+ * @len: node length
+ * @pad: if the buffer has to be padded
+ *
+ * This function prepares node at @node to be written to the media - it
+ * calculates node CRC, fills the common header, and adds proper padding up to
+ * the next minimum I/O unit if @pad is not zero.
+ */
+void ubifs_prepare_node(struct ubifs_info *c, void *node, int len, int pad)
+{
+ uint32_t crc;
+ struct ubifs_ch *ch = node;
+ unsigned long long sqnum = next_sqnum(c);
+
+ ubifs_assert(len >= UBIFS_CH_SZ);
+
+ ch->magic = cpu_to_le32(UBIFS_NODE_MAGIC);
+ ch->len = cpu_to_le32(len);
+ ch->group_type = UBIFS_NO_NODE_GROUP;
+ ch->sqnum = cpu_to_le64(sqnum);
+ ch->padding[0] = ch->padding[1] = 0;
+ crc = crc32(UBIFS_CRC32_INIT, node + 8, len - 8);
+ ch->crc = cpu_to_le32(crc);
+
+ if (pad) {
+ len = ALIGN(len, 8);
+ pad = ALIGN(len, c->min_io_size) - len;
+ ubifs_pad(c, node + len, pad);
+ }
+}
+
+/**
+ * ubifs_prep_grp_node - prepare node of a group to be written to flash.
+ * @c: UBIFS file-system description object
+ * @node: the node to pad
+ * @len: node length
+ * @last: indicates the last node of the group
+ *
+ * This function prepares node at @node to be written to the media - it
+ * calculates node CRC and fills the common header.
+ */
+void ubifs_prep_grp_node(struct ubifs_info *c, void *node, int len, int last)
+{
+ uint32_t crc;
+ struct ubifs_ch *ch = node;
+ unsigned long long sqnum = next_sqnum(c);
+
+ ubifs_assert(len >= UBIFS_CH_SZ);
+
+ ch->magic = cpu_to_le32(UBIFS_NODE_MAGIC);
+ ch->len = cpu_to_le32(len);
+ if (last)
+ ch->group_type = UBIFS_LAST_OF_NODE_GROUP;
+ else
+ ch->group_type = UBIFS_IN_NODE_GROUP;
+ ch->sqnum = cpu_to_le64(sqnum);
+ ch->padding[0] = ch->padding[1] = 0;
+ crc = crc32(UBIFS_CRC32_INIT, node + 8, len - 8);
+ ch->crc = cpu_to_le32(crc);
+}
+
+/**
+ * wbuf_timer_callback - write-buffer timer callback function.
+ * @data: timer data (write-buffer descriptor)
+ *
+ * This function is called when the write-buffer timer expires.
+ */
+static void wbuf_timer_callback_nolock(unsigned long data)
+{
+ struct ubifs_wbuf *wbuf = (struct ubifs_wbuf *)data;
+
+ wbuf->need_sync = 1;
+ wbuf->c->need_wbuf_sync = 1;
+ ubifs_wake_up_bgt(wbuf->c);
+}
+
+/**
+ * new_wbuf_timer - start new write-buffer timer.
+ * @wbuf: write-buffer descriptor
+ */
+static void new_wbuf_timer_nolock(struct ubifs_wbuf *wbuf)
+{
+ ubifs_assert(!timer_pending(&wbuf->timer));
+
+ if (!wbuf->timeout)
+ return;
+
+ wbuf->timer.expires = jiffies + wbuf->timeout;
+ add_timer(&wbuf->timer);
+}
+
+/**
+ * cancel_wbuf_timer - cancel write-buffer timer.
+ * @wbuf: write-buffer descriptor
+ */
+static void cancel_wbuf_timer_nolock(struct ubifs_wbuf *wbuf)
+{
+ /*
+ * If the syncer is waiting for the lock (from the background thread's
+ * context) and another task is changing write-buffer then the syncing
+ * should be canceled.
+ */
+ wbuf->need_sync = 0;
+ del_timer(&wbuf->timer);
+}
+
+/**
+ * ubifs_wbuf_sync_nolock - synchronize write-buffer.
+ * @wbuf: write-buffer to synchronize
+ *
+ * This function synchronizes write-buffer @buf and returns zero in case of
+ * success or a negative error code in case of failure.
+ */
+int ubifs_wbuf_sync_nolock(struct ubifs_wbuf *wbuf)
+{
+ struct ubifs_info *c = wbuf->c;
+ int err, dirt;
+
+ cancel_wbuf_timer_nolock(wbuf);
+ if (!wbuf->used || wbuf->lnum == -1)
+ /* Write-buffer is empty or not seeked */
+ return 0;
+
+ dbg_io("LEB %d:%d, %d bytes",
+ wbuf->lnum, wbuf->offs, wbuf->used);
+ ubifs_assert(!(c->vfs_sb->s_flags & MS_RDONLY));
+ ubifs_assert(!(wbuf->avail & 7));
+ ubifs_assert(wbuf->offs + c->min_io_size <= c->leb_size);
+
+ if (c->ro_media)
+ return -EROFS;
+
+ ubifs_pad(c, wbuf->buf + wbuf->used, wbuf->avail);
+ err = ubi_leb_write(c->ubi, wbuf->lnum, wbuf->buf, wbuf->offs,
+ c->min_io_size, wbuf->dtype);
+ if (err) {
+ ubifs_err("cannot write %d bytes to LEB %d:%d",
+ c->min_io_size, wbuf->lnum, wbuf->offs);
+ dbg_dump_stack();
+ return err;
+ }
+
+ dirt = wbuf->avail;
+
+ spin_lock(&wbuf->lock);
+ wbuf->offs += c->min_io_size;
+ wbuf->avail = c->min_io_size;
+ wbuf->used = 0;
+ wbuf->next_ino = 0;
+ spin_unlock(&wbuf->lock);
+
+ if (wbuf->sync_callback)
+ err = wbuf->sync_callback(c, wbuf->lnum,
+ c->leb_size - wbuf->offs, dirt);
+ return err;
+}
+
+/**
+ * ubifs_wbuf_seek_nolock - seek write-buffer.
+ * @wbuf: write-buffer
+ * @lnum: logical eraseblock number to seek to
+ * @offs: logical eraseblock offset to seek to
+ * @dtype: data type
+ *
+ * This function targets the write buffer to logical eraseblock @lnum:@offs.
+ * The write-buffer is synchronized if it is not empty. Returns zero in case of
+ * success and a negative error code in case of failure.
+ */
+int ubifs_wbuf_seek_nolock(struct ubifs_wbuf *wbuf, int lnum, int offs,
+ int dtype)
+{
+ const struct ubifs_info *c = wbuf->c;
+
+ dbg_io("LEB %d:%d", lnum, offs);
+ ubifs_assert(lnum >= 0 && lnum < c->leb_cnt);
+ ubifs_assert(offs >= 0 && offs <= c->leb_size);
+ ubifs_assert(offs % c->min_io_size == 0 && !(offs & 7));
+ ubifs_assert(lnum != wbuf->lnum);
+
+ if (wbuf->used > 0) {
+ int err = ubifs_wbuf_sync_nolock(wbuf);
+
+ if (err)
+ return err;
+ }
+
+ spin_lock(&wbuf->lock);
+ wbuf->lnum = lnum;
+ wbuf->offs = offs;
+ wbuf->avail = c->min_io_size;
+ wbuf->used = 0;
+ spin_unlock(&wbuf->lock);
+ wbuf->dtype = dtype;
+
+ return 0;
+}
+
+/**
+ * ubifs_bg_wbufs_sync - synchronize write-buffers.
+ * @c: UBIFS file-system description object
+ *
+ * This function is called by background thread to synchronize write-buffers.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+int ubifs_bg_wbufs_sync(struct ubifs_info *c)
+{
+ int err, i;
+
+ if (!c->need_wbuf_sync)
+ return 0;
+ c->need_wbuf_sync = 0;
+
+ if (c->ro_media) {
+ err = -EROFS;
+ goto out_timers;
+ }
+
+ dbg_io("synchronize");
+ for (i = 0; i < c->jhead_cnt; i++) {
+ struct ubifs_wbuf *wbuf = &c->jheads[i].wbuf;
+
+ cond_resched();
+
+ /*
+ * If the mutex is locked then wbuf is being changed, so
+ * synchronization is not necessary.
+ */
+ if (mutex_is_locked(&wbuf->io_mutex))
+ continue;
+
+ mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
+ if (!wbuf->need_sync) {
+ mutex_unlock(&wbuf->io_mutex);
+ continue;
+ }
+
+ err = ubifs_wbuf_sync_nolock(wbuf);
+ mutex_unlock(&wbuf->io_mutex);
+ if (err) {
+ ubifs_err("cannot sync write-buffer, error %d", err);
+ ubifs_ro_mode(c, err);
+ goto out_timers;
+ }
+ }
+
+ return 0;
+
+out_timers:
+ /* Cancel all timers to prevent repeated errors */
+ for (i = 0; i < c->jhead_cnt; i++) {
+ struct ubifs_wbuf *wbuf = &c->jheads[i].wbuf;
+
+ mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
+ cancel_wbuf_timer_nolock(wbuf);
+ mutex_unlock(&wbuf->io_mutex);
+ }
+ return err;
+}
+
+/**
+ * ubifs_wbuf_write_nolock - write data to flash via write-buffer.
+ * @wbuf: write-buffer
+ * @buf: node to write
+ * @len: node length
+ *
+ * This function writes data to flash via write-buffer @wbuf. This means that
+ * the last piece of the node won't reach the flash media immediately if it
+ * does not take whole minimal I/O unit. Instead, the node will sit in RAM
+ * until the write-buffer is synchronized (e.g., by timer).
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure. If the node cannot be written because there is no more
+ * space in this logical eraseblock, %-ENOSPC is returned.
+ */
+int ubifs_wbuf_write_nolock(struct ubifs_wbuf *wbuf, void *buf, int len)
+{
+ struct ubifs_info *c = wbuf->c;
+ int err, written, n, aligned_len = ALIGN(len, 8), offs;
+
+ dbg_io("%d bytes (%s) to wbuf at LEB %d:%d", len,
+ dbg_ntype(((struct ubifs_ch *)buf)->node_type), wbuf->lnum,
+ wbuf->offs + wbuf->used);
+ ubifs_assert(len > 0 && wbuf->lnum >= 0 && wbuf->lnum < c->leb_cnt);
+ ubifs_assert(wbuf->offs >= 0 && wbuf->offs % c->min_io_size == 0);
+ ubifs_assert(!(wbuf->offs & 7) && wbuf->offs <= c->leb_size);
+ ubifs_assert(wbuf->avail > 0 && wbuf->avail <= c->min_io_size);
+ ubifs_assert(mutex_is_locked(&wbuf->io_mutex));
+
+ if (c->leb_size - wbuf->offs - wbuf->used < aligned_len) {
+ err = -ENOSPC;
+ goto out;
+ }
+
+ cancel_wbuf_timer_nolock(wbuf);
+
+ if (c->ro_media)
+ return -EROFS;
+
+ if (aligned_len <= wbuf->avail) {
+ /*
+ * The node is not very large and fits entirely within
+ * write-buffer.
+ */
+ memcpy(wbuf->buf + wbuf->used, buf, len);
+
+ if (aligned_len == wbuf->avail) {
+ dbg_io("flush wbuf to LEB %d:%d", wbuf->lnum,
+ wbuf->offs);
+ err = ubi_leb_write(c->ubi, wbuf->lnum, wbuf->buf,
+ wbuf->offs, c->min_io_size,
+ wbuf->dtype);
+ if (err)
+ goto out;
+
+ spin_lock(&wbuf->lock);
+ wbuf->offs += c->min_io_size;
+ wbuf->avail = c->min_io_size;
+ wbuf->used = 0;
+ wbuf->next_ino = 0;
+ spin_unlock(&wbuf->lock);
+ } else {
+ spin_lock(&wbuf->lock);
+ wbuf->avail -= aligned_len;
+ wbuf->used += aligned_len;
+ spin_unlock(&wbuf->lock);
+ }
+
+ goto exit;
+ }
+
+ /*
+ * The node is large enough and does not fit entirely within current
+ * minimal I/O unit. We have to fill and flush write-buffer and switch
+ * to the next min. I/O unit.
+ */
+ dbg_io("flush wbuf to LEB %d:%d", wbuf->lnum, wbuf->offs);
+ memcpy(wbuf->buf + wbuf->used, buf, wbuf->avail);
+ err = ubi_leb_write(c->ubi, wbuf->lnum, wbuf->buf, wbuf->offs,
+ c->min_io_size, wbuf->dtype);
+ if (err)
+ goto out;
+
+ offs = wbuf->offs + c->min_io_size;
+ len -= wbuf->avail;
+ aligned_len -= wbuf->avail;
+ written = wbuf->avail;
+
+ /*
+ * The remaining data may take more whole min. I/O units, so write the
+ * remains multiple to min. I/O unit size directly to the flash media.
+ * We align node length to 8-byte boundary because we anyway flash wbuf
+ * if the remaining space is less than 8 bytes.
+ */
+ n = aligned_len >> c->min_io_shift;
+ if (n) {
+ n <<= c->min_io_shift;
+ dbg_io("write %d bytes to LEB %d:%d", n, wbuf->lnum, offs);
+ err = ubi_leb_write(c->ubi, wbuf->lnum, buf + written, offs, n,
+ wbuf->dtype);
+ if (err)
+ goto out;
+ offs += n;
+ aligned_len -= n;
+ len -= n;
+ written += n;
+ }
+
+ spin_lock(&wbuf->lock);
+ if (aligned_len)
+ /*
+ * And now we have what's left and what does not take whole
+ * min. I/O unit, so write it to the write-buffer and we are
+ * done.
+ */
+ memcpy(wbuf->buf, buf + written, len);
+
+ wbuf->offs = offs;
+ wbuf->used = aligned_len;
+ wbuf->avail = c->min_io_size - aligned_len;
+ wbuf->next_ino = 0;
+ spin_unlock(&wbuf->lock);
+
+exit:
+ if (wbuf->sync_callback) {
+ int free = c->leb_size - wbuf->offs - wbuf->used;
+
+ err = wbuf->sync_callback(c, wbuf->lnum, free, 0);
+ if (err)
+ goto out;
+ }
+
+ if (wbuf->used)
+ new_wbuf_timer_nolock(wbuf);
+
+ return 0;
+
+out:
+ ubifs_err("cannot write %d bytes to LEB %d:%d, error %d",
+ len, wbuf->lnum, wbuf->offs, err);
+ dbg_dump_node(c, buf);
+ dbg_dump_stack();
+ dbg_dump_leb(c, wbuf->lnum);
+ return err;
+}
+
+/**
+ * ubifs_write_node - write node to the media.
+ * @c: UBIFS file-system description object
+ * @buf: the node to write
+ * @len: node length
+ * @lnum: logical eraseblock number
+ * @offs: offset within the logical eraseblock
+ * @dtype: node life-time hint (%UBI_LONGTERM, %UBI_SHORTTERM, %UBI_UNKNOWN)
+ *
+ * This function automatically fills node magic number, assigns sequence
+ * number, and calculates node CRC checksum. The length of the @buf buffer has
+ * to be aligned to the minimal I/O unit size. This function automatically
+ * appends padding node and padding bytes if needed. Returns zero in case of
+ * success and a negative error code in case of failure.
+ */
+int ubifs_write_node(struct ubifs_info *c, void *buf, int len, int lnum,
+ int offs, int dtype)
+{
+ int err, buf_len = ALIGN(len, c->min_io_size);
+
+ dbg_io("LEB %d:%d, %s, length %d (aligned %d)",
+ lnum, offs, dbg_ntype(((struct ubifs_ch *)buf)->node_type), len,
+ buf_len);
+ ubifs_assert(lnum >= 0 && lnum < c->leb_cnt && offs >= 0);
+ ubifs_assert(offs % c->min_io_size == 0 && offs < c->leb_size);
+
+ if (c->ro_media)
+ return -EROFS;
+
+ ubifs_prepare_node(c, buf, len, 1);
+ err = ubi_leb_write(c->ubi, lnum, buf, offs, buf_len, dtype);
+ if (err) {
+ ubifs_err("cannot write %d bytes to LEB %d:%d, error %d",
+ buf_len, lnum, offs, err);
+ dbg_dump_node(c, buf);
+ dbg_dump_stack();
+ }
+
+ return err;
+}
+
+/**
+ * ubifs_read_node_wbuf - read node from the media or write-buffer.
+ * @wbuf: wbuf to check for un-written data
+ * @buf: buffer to read to
+ * @type: node type
+ * @len: node length
+ * @lnum: logical eraseblock number
+ * @offs: offset within the logical eraseblock
+ *
+ * This function reads a node of known type and length, checks it and stores
+ * in @buf. If the node partially or fully sits in the write-buffer, this
+ * function takes data from the buffer, otherwise it reads the flash media.
+ * Returns zero in case of success, %-EUCLEAN if CRC mismatched and a negative
+ * error code in case of failure.
+ */
+int ubifs_read_node_wbuf(struct ubifs_wbuf *wbuf, void *buf, int type, int len,
+ int lnum, int offs)
+{
+ const struct ubifs_info *c = wbuf->c;
+ int err, rlen, overlap;
+ struct ubifs_ch *ch = buf;
+
+ dbg_io("LEB %d:%d, %s, length %d", lnum, offs, dbg_ntype(type), len);
+ ubifs_assert(wbuf && lnum >= 0 && lnum < c->leb_cnt && offs >= 0);
+ ubifs_assert(!(offs & 7) && offs < c->leb_size);
+ ubifs_assert(type >= 0 && type < UBIFS_NODE_TYPES_CNT);
+
+ spin_lock(&wbuf->lock);
+ overlap = (lnum == wbuf->lnum && offs + len > wbuf->offs);
+ if (!overlap) {
+ /* We may safely unlock the write-buffer and read the data */
+ spin_unlock(&wbuf->lock);
+ return ubifs_read_node(c, buf, type, len, lnum, offs);
+ }
+
+ /* Don't read under wbuf */
+ rlen = wbuf->offs - offs;
+ if (rlen < 0)
+ rlen = 0;
+
+ /* Copy the rest from the write-buffer */
+ memcpy(buf + rlen, wbuf->buf + offs + rlen - wbuf->offs, len - rlen);
+ spin_unlock(&wbuf->lock);
+
+ if (rlen > 0) {
+ /* Read everything that goes before write-buffer */
+ err = ubi_read(c->ubi, lnum, buf, offs, rlen);
+ if (err && err != -EBADMSG) {
+ ubifs_err("failed to read node %d from LEB %d:%d, "
+ "error %d", type, lnum, offs, err);
+ dbg_dump_stack();
+ return err;
+ }
+ }
+
+ if (type != ch->node_type) {
+ ubifs_err("bad node type (%d but expected %d)",
+ ch->node_type, type);
+ goto out;
+ }
+
+ err = ubifs_check_node(c, buf, lnum, offs, 0);
+ if (err) {
+ ubifs_err("expected node type %d", type);
+ return err;
+ }
+
+ rlen = le32_to_cpu(ch->len);
+ if (rlen != len) {
+ ubifs_err("bad node length %d, expected %d", rlen, len);
+ goto out;
+ }
+
+ return 0;
+
+out:
+ ubifs_err("bad node at LEB %d:%d", lnum, offs);
+ dbg_dump_node(c, buf);
+ dbg_dump_stack();
+ return -EINVAL;
+}
+
+/**
+ * ubifs_read_node - read node.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to read to
+ * @type: node type
+ * @len: node length (not aligned)
+ * @lnum: logical eraseblock number
+ * @offs: offset within the logical eraseblock
+ *
+ * This function reads a node of known type and and length, checks it and
+ * stores in @buf. Returns zero in case of success, %-EUCLEAN if CRC mismatched
+ * and a negative error code in case of failure.
+ */
+int ubifs_read_node(const struct ubifs_info *c, void *buf, int type, int len,
+ int lnum, int offs)
+{
+ int err, l;
+ struct ubifs_ch *ch = buf;
+
+ dbg_io("LEB %d:%d, %s, length %d", lnum, offs, dbg_ntype(type), len);
+ ubifs_assert(lnum >= 0 && lnum < c->leb_cnt && offs >= 0);
+ ubifs_assert(len >= UBIFS_CH_SZ && offs + len <= c->leb_size);
+ ubifs_assert(!(offs & 7) && offs < c->leb_size);
+ ubifs_assert(type >= 0 && type < UBIFS_NODE_TYPES_CNT);
+
+ err = ubi_read(c->ubi, lnum, buf, offs, len);
+ if (err && err != -EBADMSG) {
+ ubifs_err("cannot read node %d from LEB %d:%d, error %d",
+ type, lnum, offs, err);
+ return err;
+ }
+
+ if (type != ch->node_type) {
+ ubifs_err("bad node type (%d but expected %d)",
+ ch->node_type, type);
+ goto out;
+ }
+
+ err = ubifs_check_node(c, buf, lnum, offs, 0);
+ if (err) {
+ ubifs_err("expected node type %d", type);
+ return err;
+ }
+
+ l = le32_to_cpu(ch->len);
+ if (l != len) {
+ ubifs_err("bad node length %d, expected %d", l, len);
+ goto out;
+ }
+
+ return 0;
+
+out:
+ ubifs_err("bad node at LEB %d:%d", lnum, offs);
+ dbg_dump_node(c, buf);
+ dbg_dump_stack();
+ return -EINVAL;
+}
+
+/**
+ * ubifs_wbuf_init - initialize write-buffer.
+ * @c: UBIFS file-system description object
+ * @wbuf: write-buffer to initialize
+ *
+ * This function initializes write buffer. Returns zero in case of success
+ * %-ENOMEM in case of failure.
+ */
+int ubifs_wbuf_init(struct ubifs_info *c, struct ubifs_wbuf *wbuf)
+{
+ size_t size;
+
+ wbuf->buf = kmalloc(c->min_io_size, GFP_KERNEL);
+ if (!wbuf->buf)
+ return -ENOMEM;
+
+ size = (c->min_io_size / UBIFS_CH_SZ + 1) * sizeof(ino_t);
+ wbuf->inodes = kmalloc(size, GFP_KERNEL);
+ if (!wbuf->inodes) {
+ kfree(wbuf->buf);
+ wbuf->buf = NULL;
+ return -ENOMEM;
+ }
+
+ wbuf->used = 0;
+ wbuf->lnum = wbuf->offs = -1;
+ wbuf->avail = c->min_io_size;
+ wbuf->dtype = UBI_UNKNOWN;
+ wbuf->sync_callback = NULL;
+ mutex_init(&wbuf->io_mutex);
+ spin_lock_init(&wbuf->lock);
+
+ wbuf->c = c;
+ init_timer(&wbuf->timer);
+ wbuf->timer.function = wbuf_timer_callback_nolock;
+ wbuf->timer.data = (unsigned long)wbuf;
+ wbuf->timeout = DEFAULT_WBUF_TIMEOUT;
+ wbuf->next_ino = 0;
+
+ return 0;
+}
+
+/**
+ * ubifs_wbuf_add_ino_nolock - add an inode number into the wbuf inode array.
+ * @wbuf: the write-buffer whereto add
+ * @inum: the inode number
+ *
+ * This function adds an inode number to the inode array of the write-buffer.
+ */
+void ubifs_wbuf_add_ino_nolock(struct ubifs_wbuf *wbuf, ino_t inum)
+{
+ if (!wbuf->buf)
+ /* NOR flash or something similar */
+ return;
+
+ spin_lock(&wbuf->lock);
+ if (wbuf->used)
+ wbuf->inodes[wbuf->next_ino++] = inum;
+ spin_unlock(&wbuf->lock);
+}
+
+/**
+ * wbuf_has_ino - returns if the wbuf contains data from the inode.
+ * @wbuf: the write-buffer
+ * @inum: the inode number
+ *
+ * This function returns with %1 if the write-buffer contains some data from the
+ * given inode otherwise it returns with %0.
+ */
+static int wbuf_has_ino(struct ubifs_wbuf *wbuf, ino_t inum)
+{
+ int i, ret = 0;
+
+ spin_lock(&wbuf->lock);
+ for (i = 0; i < wbuf->next_ino; i++)
+ if (inum == wbuf->inodes[i]) {
+ ret = 1;
+ break;
+ }
+ spin_unlock(&wbuf->lock);
+
+ return ret;
+}
+
+/**
+ * ubifs_sync_wbufs_by_inode - synchronize write-buffers for an inode.
+ * @c: UBIFS file-system description object
+ * @inode: inode to synchronize
+ *
+ * This function synchronizes write-buffers which contain nodes belonging to
+ * @inode. Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+int ubifs_sync_wbufs_by_inode(struct ubifs_info *c, struct inode *inode)
+{
+ int i, err = 0;
+
+ for (i = 0; i < c->jhead_cnt; i++) {
+ struct ubifs_wbuf *wbuf = &c->jheads[i].wbuf;
+
+ if (i == GCHD)
+ /*
+ * GC head is special, do not look at it. Even if the
+ * head contains something related to this inode, it is
+ * a _copy_ of corresponding on-flash node which sits
+ * somewhere else.
+ */
+ continue;
+
+ if (!wbuf_has_ino(wbuf, inode->i_ino))
+ continue;
+
+ mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
+ if (wbuf_has_ino(wbuf, inode->i_ino))
+ err = ubifs_wbuf_sync_nolock(wbuf);
+ mutex_unlock(&wbuf->io_mutex);
+
+ if (err) {
+ ubifs_ro_mode(c, err);
+ return err;
+ }
+ }
+ return 0;
+}
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ * Copyright (C) 2006, 2007 University of Szeged, Hungary
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Zoltan Sogor
+ * Artem Bityutskiy (Битюцкий Артём)
+ * Adrian Hunter
+ */
+
+/* This file implements EXT2-compatible extended attribute ioctl() calls */
+
+#include <linux/compat.h>
+#include <linux/smp_lock.h>
+#include <linux/mount.h>
+#include "ubifs.h"
+
+/**
+ * ubifs_set_inode_flags - set VFS inode flags.
+ * @inode: VFS inode to set flags for
+ *
+ * This function propagates flags from UBIFS inode object to VFS inode object.
+ */
+void ubifs_set_inode_flags(struct inode *inode)
+{
+ unsigned int flags = ubifs_inode(inode)->flags;
+
+ inode->i_flags &= ~(S_SYNC | S_APPEND | S_IMMUTABLE | S_DIRSYNC);
+ if (flags & UBIFS_SYNC_FL)
+ inode->i_flags |= S_SYNC;
+ if (flags & UBIFS_APPEND_FL)
+ inode->i_flags |= S_APPEND;
+ if (flags & UBIFS_IMMUTABLE_FL)
+ inode->i_flags |= S_IMMUTABLE;
+ if (flags & UBIFS_DIRSYNC_FL)
+ inode->i_flags |= S_DIRSYNC;
+}
+
+/*
+ * ioctl2ubifs - convert ioctl inode flags to UBIFS inode flags.
+ * @ioctl_flags: flags to convert
+ *
+ * This function convert ioctl flags (@FS_COMPR_FL, etc) to UBIFS inode flags
+ * (@UBIFS_COMPR_FL, etc).
+ */
+static int ioctl2ubifs(int ioctl_flags)
+{
+ int ubifs_flags = 0;
+
+ if (ioctl_flags & FS_COMPR_FL)
+ ubifs_flags |= UBIFS_COMPR_FL;
+ if (ioctl_flags & FS_SYNC_FL)
+ ubifs_flags |= UBIFS_SYNC_FL;
+ if (ioctl_flags & FS_APPEND_FL)
+ ubifs_flags |= UBIFS_APPEND_FL;
+ if (ioctl_flags & FS_IMMUTABLE_FL)
+ ubifs_flags |= UBIFS_IMMUTABLE_FL;
+ if (ioctl_flags & FS_DIRSYNC_FL)
+ ubifs_flags |= UBIFS_DIRSYNC_FL;
+
+ return ubifs_flags;
+}
+
+/*
+ * ubifs2ioctl - convert UBIFS inode flags to ioctl inode flags.
+ * @ubifs_flags: flags to convert
+ *
+ * This function convert UBIFS (@UBIFS_COMPR_FL, etc) to ioctl flags
+ * (@FS_COMPR_FL, etc).
+ */
+static int ubifs2ioctl(int ubifs_flags)
+{
+ int ioctl_flags = 0;
+
+ if (ubifs_flags & UBIFS_COMPR_FL)
+ ioctl_flags |= FS_COMPR_FL;
+ if (ubifs_flags & UBIFS_SYNC_FL)
+ ioctl_flags |= FS_SYNC_FL;
+ if (ubifs_flags & UBIFS_APPEND_FL)
+ ioctl_flags |= FS_APPEND_FL;
+ if (ubifs_flags & UBIFS_IMMUTABLE_FL)
+ ioctl_flags |= FS_IMMUTABLE_FL;
+ if (ubifs_flags & UBIFS_DIRSYNC_FL)
+ ioctl_flags |= FS_DIRSYNC_FL;
+
+ return ioctl_flags;
+}
+
+static int setflags(struct inode *inode, int flags)
+{
+ int oldflags, err, release;
+ struct ubifs_inode *ui = ubifs_inode(inode);
+ struct ubifs_info *c = inode->i_sb->s_fs_info;
+ struct ubifs_budget_req req = { .dirtied_ino = 1,
+ .dirtied_ino_d = ui->data_len };
+
+ err = ubifs_budget_space(c, &req);
+ if (err)
+ return err;
+
+ /*
+ * The IMMUTABLE and APPEND_ONLY flags can only be changed by
+ * the relevant capability.
+ */
+ mutex_lock(&ui->ui_mutex);
+ oldflags = ubifs2ioctl(ui->flags);
+ if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
+ if (!capable(CAP_LINUX_IMMUTABLE)) {
+ err = -EPERM;
+ goto out_unlock;
+ }
+ }
+
+ ui->flags = ioctl2ubifs(flags);
+ ubifs_set_inode_flags(inode);
+ inode->i_ctime = ubifs_current_time(inode);
+ release = ui->dirty;
+ mark_inode_dirty_sync(inode);
+ mutex_unlock(&ui->ui_mutex);
+
+ if (release)
+ ubifs_release_budget(c, &req);
+ if (IS_SYNC(inode))
+ err = write_inode_now(inode, 1);
+ return err;
+
+out_unlock:
+ ubifs_err("can't modify inode %lu attributes", inode->i_ino);
+ mutex_unlock(&ui->ui_mutex);
+ ubifs_release_budget(c, &req);
+ return err;
+}
+
+long ubifs_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ int flags, err;
+ struct inode *inode = file->f_path.dentry->d_inode;
+
+ switch (cmd) {
+ case FS_IOC_GETFLAGS:
+ flags = ubifs2ioctl(ubifs_inode(inode)->flags);
+
+ return put_user(flags, (int __user *) arg);
+
+ case FS_IOC_SETFLAGS: {
+ if (IS_RDONLY(inode))
+ return -EROFS;
+
+ if (!is_owner_or_cap(inode))
+ return -EACCES;
+
+ if (get_user(flags, (int __user *) arg))
+ return -EFAULT;
+
+ if (!S_ISDIR(inode->i_mode))
+ flags &= ~FS_DIRSYNC_FL;
+
+ /*
+ * Make sure the file-system is read-write and make sure it
+ * will not become read-only while we are changing the flags.
+ */
+ err = mnt_want_write(file->f_path.mnt);
+ if (err)
+ return err;
+ err = setflags(inode, flags);
+ mnt_drop_write(file->f_path.mnt);
+ return err;
+ }
+
+ default:
+ return -ENOTTY;
+ }
+}
+
+#ifdef CONFIG_COMPAT
+long ubifs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ switch (cmd) {
+ case FS_IOC32_GETFLAGS:
+ cmd = FS_IOC_GETFLAGS;
+ break;
+ case FS_IOC32_SETFLAGS:
+ cmd = FS_IOC_SETFLAGS;
+ break;
+ default:
+ return -ENOIOCTLCMD;
+ }
+ return ubifs_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
+}
+#endif
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ * Adrian Hunter
+ */
+
+/*
+ * This file implements UBIFS journal.
+ *
+ * The journal consists of 2 parts - the log and bud LEBs. The log has fixed
+ * length and position, while a bud logical eraseblock is any LEB in the main
+ * area. Buds contain file system data - data nodes, inode nodes, etc. The log
+ * contains only references to buds and some other stuff like commit
+ * start node. The idea is that when we commit the journal, we do
+ * not copy the data, the buds just become indexed. Since after the commit the
+ * nodes in bud eraseblocks become leaf nodes of the file system index tree, we
+ * use term "bud". Analogy is obvious, bud eraseblocks contain nodes which will
+ * become leafs in the future.
+ *
+ * The journal is multi-headed because we want to write data to the journal as
+ * optimally as possible. It is nice to have nodes belonging to the same inode
+ * in one LEB, so we may write data owned by different inodes to different
+ * journal heads, although at present only one data head is used.
+ *
+ * For recovery reasons, the base head contains all inode nodes, all directory
+ * entry nodes and all truncate nodes. This means that the other heads contain
+ * only data nodes.
+ *
+ * Bud LEBs may be half-indexed. For example, if the bud was not full at the
+ * time of commit, the bud is retained to continue to be used in the journal,
+ * even though the "front" of the LEB is now indexed. In that case, the log
+ * reference contains the offset where the bud starts for the purposes of the
+ * journal.
+ *
+ * The journal size has to be limited, because the larger is the journal, the
+ * longer it takes to mount UBIFS (scanning the journal) and the more memory it
+ * takes (indexing in the TNC).
+ *
+ * All the journal write operations like 'ubifs_jnl_update()' here, which write
+ * multiple UBIFS nodes to the journal at one go, are atomic with respect to
+ * unclean reboots. Should the unclean reboot happen, the recovery code drops
+ * all the nodes.
+ */
+
+#include "ubifs.h"
+
+/**
+ * zero_ino_node_unused - zero out unused fields of an on-flash inode node.
+ * @ino: the inode to zero out
+ */
+static inline void zero_ino_node_unused(struct ubifs_ino_node *ino)
+{
+ memset(ino->padding1, 0, 4);
+ memset(ino->padding2, 0, 26);
+}
+
+/**
+ * zero_dent_node_unused - zero out unused fields of an on-flash directory
+ * entry node.
+ * @dent: the directory entry to zero out
+ */
+static inline void zero_dent_node_unused(struct ubifs_dent_node *dent)
+{
+ dent->padding1 = 0;
+ memset(dent->padding2, 0, 4);
+}
+
+/**
+ * zero_data_node_unused - zero out unused fields of an on-flash data node.
+ * @data: the data node to zero out
+ */
+static inline void zero_data_node_unused(struct ubifs_data_node *data)
+{
+ memset(data->padding, 0, 2);
+}
+
+/**
+ * zero_trun_node_unused - zero out unused fields of an on-flash truncation
+ * node.
+ * @trun: the truncation node to zero out
+ */
+static inline void zero_trun_node_unused(struct ubifs_trun_node *trun)
+{
+ memset(trun->padding, 0, 12);
+}
+
+/**
+ * reserve_space - reserve space in the journal.
+ * @c: UBIFS file-system description object
+ * @jhead: journal head number
+ * @len: node length
+ *
+ * This function reserves space in journal head @head. If the reservation
+ * succeeded, the journal head stays locked and later has to be unlocked using
+ * 'release_head()'. 'write_node()' and 'write_head()' functions also unlock
+ * it. Returns zero in case of success, %-EAGAIN if commit has to be done, and
+ * other negative error codes in case of other failures.
+ */
+static int reserve_space(struct ubifs_info *c, int jhead, int len)
+{
+ int err = 0, err1, retries = 0, avail, lnum, offs, free, squeeze;
+ struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf;
+
+ /*
+ * Typically, the base head has smaller nodes written to it, so it is
+ * better to try to allocate space at the ends of eraseblocks. This is
+ * what the squeeze parameter does.
+ */
+ squeeze = (jhead == BASEHD);
+again:
+ mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
+
+ if (c->ro_media) {
+ err = -EROFS;
+ goto out_unlock;
+ }
+
+ avail = c->leb_size - wbuf->offs - wbuf->used;
+ if (wbuf->lnum != -1 && avail >= len)
+ return 0;
+
+ /*
+ * Write buffer wasn't seek'ed or there is no enough space - look for an
+ * LEB with some empty space.
+ */
+ lnum = ubifs_find_free_space(c, len, &free, squeeze);
+ if (lnum >= 0) {
+ /* Found an LEB, add it to the journal head */
+ offs = c->leb_size - free;
+ err = ubifs_add_bud_to_log(c, jhead, lnum, offs);
+ if (err)
+ goto out_return;
+ /* A new bud was successfully allocated and added to the log */
+ goto out;
+ }
+
+ err = lnum;
+ if (err != -ENOSPC)
+ goto out_unlock;
+
+ /*
+ * No free space, we have to run garbage collector to make
+ * some. But the write-buffer mutex has to be unlocked because
+ * GC also takes it.
+ */
+ dbg_jnl("no free space jhead %d, run GC", jhead);
+ mutex_unlock(&wbuf->io_mutex);
+
+ lnum = ubifs_garbage_collect(c, 0);
+ if (lnum < 0) {
+ err = lnum;
+ if (err != -ENOSPC)
+ return err;
+
+ /*
+ * GC could not make a free LEB. But someone else may
+ * have allocated new bud for this journal head,
+ * because we dropped @wbuf->io_mutex, so try once
+ * again.
+ */
+ dbg_jnl("GC couldn't make a free LEB for jhead %d", jhead);
+ if (retries++ < 2) {
+ dbg_jnl("retry (%d)", retries);
+ goto again;
+ }
+
+ dbg_jnl("return -ENOSPC");
+ return err;
+ }
+
+ mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
+ dbg_jnl("got LEB %d for jhead %d", lnum, jhead);
+ avail = c->leb_size - wbuf->offs - wbuf->used;
+
+ if (wbuf->lnum != -1 && avail >= len) {
+ /*
+ * Someone else has switched the journal head and we have
+ * enough space now. This happens when more then one process is
+ * trying to write to the same journal head at the same time.
+ */
+ dbg_jnl("return LEB %d back, already have LEB %d:%d",
+ lnum, wbuf->lnum, wbuf->offs + wbuf->used);
+ err = ubifs_return_leb(c, lnum);
+ if (err)
+ goto out_unlock;
+ return 0;
+ }
+
+ err = ubifs_add_bud_to_log(c, jhead, lnum, 0);
+ if (err)
+ goto out_return;
+ offs = 0;
+
+out:
+ err = ubifs_wbuf_seek_nolock(wbuf, lnum, offs, UBI_SHORTTERM);
+ if (err)
+ goto out_unlock;
+
+ return 0;
+
+out_unlock:
+ mutex_unlock(&wbuf->io_mutex);
+ return err;
+
+out_return:
+ /* An error occurred and the LEB has to be returned to lprops */
+ ubifs_assert(err < 0);
+ err1 = ubifs_return_leb(c, lnum);
+ if (err1 && err == -EAGAIN)
+ /*
+ * Return original error code only if it is not %-EAGAIN,
+ * which is not really an error. Otherwise, return the error
+ * code of 'ubifs_return_leb()'.
+ */
+ err = err1;
+ mutex_unlock(&wbuf->io_mutex);
+ return err;
+}
+
+/**
+ * write_node - write node to a journal head.
+ * @c: UBIFS file-system description object
+ * @jhead: journal head
+ * @node: node to write
+ * @len: node length
+ * @lnum: LEB number written is returned here
+ * @offs: offset written is returned here
+ *
+ * This function writes a node to reserved space of journal head @jhead.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+static int write_node(struct ubifs_info *c, int jhead, void *node, int len,
+ int *lnum, int *offs)
+{
+ struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf;
+
+ ubifs_assert(jhead != GCHD);
+
+ *lnum = c->jheads[jhead].wbuf.lnum;
+ *offs = c->jheads[jhead].wbuf.offs + c->jheads[jhead].wbuf.used;
+
+ dbg_jnl("jhead %d, LEB %d:%d, len %d", jhead, *lnum, *offs, len);
+ ubifs_prepare_node(c, node, len, 0);
+
+ return ubifs_wbuf_write_nolock(wbuf, node, len);
+}
+
+/**
+ * write_head - write data to a journal head.
+ * @c: UBIFS file-system description object
+ * @jhead: journal head
+ * @buf: buffer to write
+ * @len: length to write
+ * @lnum: LEB number written is returned here
+ * @offs: offset written is returned here
+ * @sync: non-zero if the write-buffer has to by synchronized
+ *
+ * This function is the same as 'write_node()' but it does not assume the
+ * buffer it is writing is a node, so it does not prepare it (which means
+ * initializing common header and calculating CRC).
+ */
+static int write_head(struct ubifs_info *c, int jhead, void *buf, int len,
+ int *lnum, int *offs, int sync)
+{
+ int err;
+ struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf;
+
+ ubifs_assert(jhead != GCHD);
+
+ *lnum = c->jheads[jhead].wbuf.lnum;
+ *offs = c->jheads[jhead].wbuf.offs + c->jheads[jhead].wbuf.used;
+ dbg_jnl("jhead %d, LEB %d:%d, len %d", jhead, *lnum, *offs, len);
+
+ err = ubifs_wbuf_write_nolock(wbuf, buf, len);
+ if (err)
+ return err;
+ if (sync)
+ err = ubifs_wbuf_sync_nolock(wbuf);
+ return err;
+}
+
+/**
+ * make_reservation - reserve journal space.
+ * @c: UBIFS file-system description object
+ * @jhead: journal head
+ * @len: how many bytes to reserve
+ *
+ * This function makes space reservation in journal head @jhead. The function
+ * takes the commit lock and locks the journal head, and the caller has to
+ * unlock the head and finish the reservation with 'finish_reservation()'.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ *
+ * Note, the journal head may be unlocked as soon as the data is written, while
+ * the commit lock has to be released after the data has been added to the
+ * TNC.
+ */
+static int make_reservation(struct ubifs_info *c, int jhead, int len)
+{
+ int err, cmt_retries = 0, nospc_retries = 0;
+
+again:
+ down_read(&c->commit_sem);
+ err = reserve_space(c, jhead, len);
+ if (!err)
+ return 0;
+ up_read(&c->commit_sem);
+
+ if (err == -ENOSPC) {
+ /*
+ * GC could not make any progress. We should try to commit
+ * once because it could make some dirty space and GC would
+ * make progress, so make the error -EAGAIN so that the below
+ * will commit and re-try.
+ */
+ if (nospc_retries++ < 2) {
+ dbg_jnl("no space, retry");
+ err = -EAGAIN;
+ }
+
+ /*
+ * This means that the budgeting is incorrect. We always have
+ * to be able to write to the media, because all operations are
+ * budgeted. Deletions are not budgeted, though, but we reserve
+ * an extra LEB for them.
+ */
+ }
+
+ if (err != -EAGAIN)
+ goto out;
+
+ /*
+ * -EAGAIN means that the journal is full or too large, or the above
+ * code wants to do one commit. Do this and re-try.
+ */
+ if (cmt_retries > 128) {
+ /*
+ * This should not happen unless the journal size limitations
+ * are too tough.
+ */
+ ubifs_err("stuck in space allocation");
+ err = -ENOSPC;
+ goto out;
+ } else if (cmt_retries > 32)
+ ubifs_warn("too many space allocation re-tries (%d)",
+ cmt_retries);
+
+ dbg_jnl("-EAGAIN, commit and retry (retried %d times)",
+ cmt_retries);
+ cmt_retries += 1;
+
+ err = ubifs_run_commit(c);
+ if (err)
+ return err;
+ goto again;
+
+out:
+ ubifs_err("cannot reserve %d bytes in jhead %d, error %d",
+ len, jhead, err);
+ if (err == -ENOSPC) {
+ /* This are some budgeting problems, print useful information */
+ down_write(&c->commit_sem);
+ spin_lock(&c->space_lock);
+ dbg_dump_stack();
+ dbg_dump_budg(c);
+ spin_unlock(&c->space_lock);
+ dbg_dump_lprops(c);
+ cmt_retries = dbg_check_lprops(c);
+ up_write(&c->commit_sem);
+ }
+ return err;
+}
+
+/**
+ * release_head - release a journal head.
+ * @c: UBIFS file-system description object
+ * @jhead: journal head
+ *
+ * This function releases journal head @jhead which was locked by
+ * the 'make_reservation()' function. It has to be called after each successful
+ * 'make_reservation()' invocation.
+ */
+static inline void release_head(struct ubifs_info *c, int jhead)
+{
+ mutex_unlock(&c->jheads[jhead].wbuf.io_mutex);
+}
+
+/**
+ * finish_reservation - finish a reservation.
+ * @c: UBIFS file-system description object
+ *
+ * This function finishes journal space reservation. It must be called after
+ * 'make_reservation()'.
+ */
+static void finish_reservation(struct ubifs_info *c)
+{
+ up_read(&c->commit_sem);
+}
+
+/**
+ * get_dent_type - translate VFS inode mode to UBIFS directory entry type.
+ * @mode: inode mode
+ */
+static int get_dent_type(int mode)
+{
+ switch (mode & S_IFMT) {
+ case S_IFREG:
+ return UBIFS_ITYPE_REG;
+ case S_IFDIR:
+ return UBIFS_ITYPE_DIR;
+ case S_IFLNK:
+ return UBIFS_ITYPE_LNK;
+ case S_IFBLK:
+ return UBIFS_ITYPE_BLK;
+ case S_IFCHR:
+ return UBIFS_ITYPE_CHR;
+ case S_IFIFO:
+ return UBIFS_ITYPE_FIFO;
+ case S_IFSOCK:
+ return UBIFS_ITYPE_SOCK;
+ default:
+ BUG();
+ }
+ return 0;
+}
+
+/**
+ * pack_inode - pack an inode node.
+ * @c: UBIFS file-system description object
+ * @ino: buffer in which to pack inode node
+ * @inode: inode to pack
+ * @last: indicates the last node of the group
+ * @last_reference: non-zero if this is a deletion inode
+ */
+static void pack_inode(struct ubifs_info *c, struct ubifs_ino_node *ino,
+ const struct inode *inode, int last,
+ int last_reference)
+{
+ int data_len = 0;
+ struct ubifs_inode *ui = ubifs_inode(inode);
+
+ ino->ch.node_type = UBIFS_INO_NODE;
+ ino_key_init_flash(c, &ino->key, inode->i_ino);
+ ino->creat_sqnum = cpu_to_le64(ui->creat_sqnum);
+ ino->atime_sec = cpu_to_le64(inode->i_atime.tv_sec);
+ ino->atime_nsec = cpu_to_le32(inode->i_atime.tv_nsec);
+ ino->ctime_sec = cpu_to_le64(inode->i_ctime.tv_sec);
+ ino->ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
+ ino->mtime_sec = cpu_to_le64(inode->i_mtime.tv_sec);
+ ino->mtime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
+ ino->uid = cpu_to_le32(inode->i_uid);
+ ino->gid = cpu_to_le32(inode->i_gid);
+ ino->mode = cpu_to_le32(inode->i_mode);
+ ino->flags = cpu_to_le32(ui->flags);
+ ino->size = cpu_to_le64(ui->ui_size);
+ ino->nlink = cpu_to_le32(inode->i_nlink);
+ ino->compr_type = cpu_to_le16(ui->compr_type);
+ ino->data_len = cpu_to_le32(ui->data_len);
+ ino->xattr_cnt = cpu_to_le32(ui->xattr_cnt);
+ ino->xattr_size = cpu_to_le32(ui->xattr_size);
+ ino->xattr_names = cpu_to_le32(ui->xattr_names);
+ zero_ino_node_unused(ino);
+
+ /*
+ * Drop the attached data if this is a deletion inode, the data is not
+ * needed anymore.
+ */
+ if (!last_reference) {
+ memcpy(ino->data, ui->data, ui->data_len);
+ data_len = ui->data_len;
+ }
+
+ ubifs_prep_grp_node(c, ino, UBIFS_INO_NODE_SZ + data_len, last);
+}
+
+/**
+ * mark_inode_clean - mark UBIFS inode as clean.
+ * @c: UBIFS file-system description object
+ * @ui: UBIFS inode to mark as clean
+ *
+ * This helper function marks UBIFS inode @ui as clean by cleaning the
+ * @ui->dirty flag and releasing its budget. Note, VFS may still treat the
+ * inode as dirty and try to write it back, but 'ubifs_write_inode()' would
+ * just do nothing.
+ */
+static void mark_inode_clean(struct ubifs_info *c, struct ubifs_inode *ui)
+{
+ if (ui->dirty)
+ ubifs_release_dirty_inode_budget(c, ui);
+ ui->dirty = 0;
+}
+
+/**
+ * ubifs_jnl_update - update inode.
+ * @c: UBIFS file-system description object
+ * @dir: parent inode or host inode in case of extended attributes
+ * @nm: directory entry name
+ * @inode: inode to update
+ * @deletion: indicates a directory entry deletion i.e unlink or rmdir
+ * @xent: non-zero if the directory entry is an extended attribute entry
+ *
+ * This function updates an inode by writing a directory entry (or extended
+ * attribute entry), the inode itself, and the parent directory inode (or the
+ * host inode) to the journal.
+ *
+ * The function writes the host inode @dir last, which is important in case of
+ * extended attributes. Indeed, then we guarantee that if the host inode gets
+ * synchronized (with 'fsync()'), and the write-buffer it sits in gets flushed,
+ * the extended attribute inode gets flushed too. And this is exactly what the
+ * user expects - synchronizing the host inode synchronizes its extended
+ * attributes. Similarly, this guarantees that if @dir is synchronized, its
+ * directory entry corresponding to @nm gets synchronized too.
+ *
+ * If the inode (@inode) or the parent directory (@dir) are synchronous, this
+ * function synchronizes the write-buffer.
+ *
+ * This function marks the @dir and @inode inodes as clean and returns zero on
+ * success. In case of failure, a negative error code is returned.
+ */
+int ubifs_jnl_update(struct ubifs_info *c, const struct inode *dir,
+ const struct qstr *nm, const struct inode *inode,
+ int deletion, int xent)
+{
+ int err, dlen, ilen, len, lnum, ino_offs, dent_offs;
+ int aligned_dlen, aligned_ilen, sync = IS_DIRSYNC(dir);
+ int last_reference = !!(deletion && inode->i_nlink == 0);
+ struct ubifs_inode *ui = ubifs_inode(inode);
+ struct ubifs_inode *dir_ui = ubifs_inode(dir);
+ struct ubifs_dent_node *dent;
+ struct ubifs_ino_node *ino;
+ union ubifs_key dent_key, ino_key;
+
+ dbg_jnl("ino %lu, dent '%.*s', data len %d in dir ino %lu",
+ inode->i_ino, nm->len, nm->name, ui->data_len, dir->i_ino);
+ ubifs_assert(dir_ui->data_len == 0);
+ ubifs_assert(mutex_is_locked(&dir_ui->ui_mutex));
+
+ dlen = UBIFS_DENT_NODE_SZ + nm->len + 1;
+ ilen = UBIFS_INO_NODE_SZ;
+
+ /*
+ * If the last reference to the inode is being deleted, then there is
+ * no need to attach and write inode data, it is being deleted anyway.
+ * And if the inode is being deleted, no need to synchronize
+ * write-buffer even if the inode is synchronous.
+ */
+ if (!last_reference) {
+ ilen += ui->data_len;
+ sync |= IS_SYNC(inode);
+ }
+
+ aligned_dlen = ALIGN(dlen, 8);
+ aligned_ilen = ALIGN(ilen, 8);
+ len = aligned_dlen + aligned_ilen + UBIFS_INO_NODE_SZ;
+ dent = kmalloc(len, GFP_NOFS);
+ if (!dent)
+ return -ENOMEM;
+
+ /* Make reservation before allocating sequence numbers */
+ err = make_reservation(c, BASEHD, len);
+ if (err)
+ goto out_free;
+
+ if (!xent) {
+ dent->ch.node_type = UBIFS_DENT_NODE;
+ dent_key_init(c, &dent_key, dir->i_ino, nm);
+ } else {
+ dent->ch.node_type = UBIFS_XENT_NODE;
+ xent_key_init(c, &dent_key, dir->i_ino, nm);
+ }
+
+ key_write(c, &dent_key, dent->key);
+ dent->inum = deletion ? 0 : cpu_to_le64(inode->i_ino);
+ dent->type = get_dent_type(inode->i_mode);
+ dent->nlen = cpu_to_le16(nm->len);
+ memcpy(dent->name, nm->name, nm->len);
+ dent->name[nm->len] = '\0';
+ zero_dent_node_unused(dent);
+ ubifs_prep_grp_node(c, dent, dlen, 0);
+
+ ino = (void *)dent + aligned_dlen;
+ pack_inode(c, ino, inode, 0, last_reference);
+ ino = (void *)ino + aligned_ilen;
+ pack_inode(c, ino, dir, 1, 0);
+
+ if (last_reference) {
+ err = ubifs_add_orphan(c, inode->i_ino);
+ if (err) {
+ release_head(c, BASEHD);
+ goto out_finish;
+ }
+ }
+
+ err = write_head(c, BASEHD, dent, len, &lnum, &dent_offs, sync);
+ if (err)
+ goto out_release;
+ if (!sync) {
+ struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
+
+ ubifs_wbuf_add_ino_nolock(wbuf, inode->i_ino);
+ ubifs_wbuf_add_ino_nolock(wbuf, dir->i_ino);
+ }
+ release_head(c, BASEHD);
+ kfree(dent);
+
+ if (deletion) {
+ err = ubifs_tnc_remove_nm(c, &dent_key, nm);
+ if (err)
+ goto out_ro;
+ err = ubifs_add_dirt(c, lnum, dlen);
+ } else
+ err = ubifs_tnc_add_nm(c, &dent_key, lnum, dent_offs, dlen, nm);
+ if (err)
+ goto out_ro;
+
+ /*
+ * Note, we do not remove the inode from TNC even if the last reference
+ * to it has just been deleted, because the inode may still be opened.
+ * Instead, the inode has been added to orphan lists and the orphan
+ * subsystem will take further care about it.
+ */
+ ino_key_init(c, &ino_key, inode->i_ino);
+ ino_offs = dent_offs + aligned_dlen;
+ err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, ilen);
+ if (err)
+ goto out_ro;
+
+ ino_key_init(c, &ino_key, dir->i_ino);
+ ino_offs += aligned_ilen;
+ err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, UBIFS_INO_NODE_SZ);
+ if (err)
+ goto out_ro;
+
+ finish_reservation(c);
+ spin_lock(&ui->ui_lock);
+ ui->synced_i_size = ui->ui_size;
+ spin_unlock(&ui->ui_lock);
+ mark_inode_clean(c, ui);
+ mark_inode_clean(c, dir_ui);
+ return 0;
+
+out_finish:
+ finish_reservation(c);
+out_free:
+ kfree(dent);
+ return err;
+
+out_release:
+ release_head(c, BASEHD);
+out_ro:
+ ubifs_ro_mode(c, err);
+ if (last_reference)
+ ubifs_delete_orphan(c, inode->i_ino);
+ finish_reservation(c);
+ return err;
+}
+
+/**
+ * ubifs_jnl_write_data - write a data node to the journal.
+ * @c: UBIFS file-system description object
+ * @inode: inode the data node belongs to
+ * @key: node key
+ * @buf: buffer to write
+ * @len: data length (must not exceed %UBIFS_BLOCK_SIZE)
+ *
+ * This function writes a data node to the journal. Returns %0 if the data node
+ * was successfully written, and a negative error code in case of failure.
+ */
+int ubifs_jnl_write_data(struct ubifs_info *c, const struct inode *inode,
+ const union ubifs_key *key, const void *buf, int len)
+{
+ struct ubifs_data_node *data;
+ int err, lnum, offs, compr_type, out_len;
+ int dlen = UBIFS_DATA_NODE_SZ + UBIFS_BLOCK_SIZE * WORST_COMPR_FACTOR;
+ struct ubifs_inode *ui = ubifs_inode(inode);
+
+ dbg_jnl("ino %lu, blk %u, len %d, key %s", key_inum(c, key),
+ key_block(c, key), len, DBGKEY(key));
+ ubifs_assert(len <= UBIFS_BLOCK_SIZE);
+
+ data = kmalloc(dlen, GFP_NOFS);
+ if (!data)
+ return -ENOMEM;
+
+ data->ch.node_type = UBIFS_DATA_NODE;
+ key_write(c, key, &data->key);
+ data->size = cpu_to_le32(len);
+ zero_data_node_unused(data);
+
+ if (!(ui->flags && UBIFS_COMPR_FL))
+ /* Compression is disabled for this inode */
+ compr_type = UBIFS_COMPR_NONE;
+ else
+ compr_type = ui->compr_type;
+
+ out_len = dlen - UBIFS_DATA_NODE_SZ;
+ ubifs_compress(buf, len, &data->data, &out_len, &compr_type);
+ ubifs_assert(out_len <= UBIFS_BLOCK_SIZE);
+
+ dlen = UBIFS_DATA_NODE_SZ + out_len;
+ data->compr_type = cpu_to_le16(compr_type);
+
+ /* Make reservation before allocating sequence numbers */
+ err = make_reservation(c, DATAHD, dlen);
+ if (err)
+ goto out_free;
+
+ err = write_node(c, DATAHD, data, dlen, &lnum, &offs);
+ if (err)
+ goto out_release;
+ ubifs_wbuf_add_ino_nolock(&c->jheads[DATAHD].wbuf, key_inum(c, key));
+ release_head(c, DATAHD);
+
+ err = ubifs_tnc_add(c, key, lnum, offs, dlen);
+ if (err)
+ goto out_ro;
+
+ finish_reservation(c);
+ kfree(data);
+ return 0;
+
+out_release:
+ release_head(c, DATAHD);
+out_ro:
+ ubifs_ro_mode(c, err);
+ finish_reservation(c);
+out_free:
+ kfree(data);
+ return err;
+}
+
+/**
+ * ubifs_jnl_write_inode - flush inode to the journal.
+ * @c: UBIFS file-system description object
+ * @inode: inode to flush
+ * @deletion: inode has been deleted
+ *
+ * This function writes inode @inode to the journal. If the inode is
+ * synchronous, it also synchronizes the write-buffer. Returns zero in case of
+ * success and a negative error code in case of failure.
+ */
+int ubifs_jnl_write_inode(struct ubifs_info *c, const struct inode *inode,
+ int deletion)
+{
+ int err, len, lnum, offs, sync = 0;
+ struct ubifs_ino_node *ino;
+ struct ubifs_inode *ui = ubifs_inode(inode);
+
+ dbg_jnl("ino %lu%s", inode->i_ino,
+ deletion ? " (last reference)" : "");
+ if (deletion)
+ ubifs_assert(inode->i_nlink == 0);
+
+ len = UBIFS_INO_NODE_SZ;
+ /*
+ * If the inode is being deleted, do not write the attached data. No
+ * need to synchronize the write-buffer either.
+ */
+ if (!deletion) {
+ len += ui->data_len;
+ sync = IS_SYNC(inode);
+ }
+ ino = kmalloc(len, GFP_NOFS);
+ if (!ino)
+ return -ENOMEM;
+
+ /* Make reservation before allocating sequence numbers */
+ err = make_reservation(c, BASEHD, len);
+ if (err)
+ goto out_free;
+
+ pack_inode(c, ino, inode, 1, deletion);
+ err = write_head(c, BASEHD, ino, len, &lnum, &offs, sync);
+ if (err)
+ goto out_release;
+ if (!sync)
+ ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf,
+ inode->i_ino);
+ release_head(c, BASEHD);
+
+ if (deletion) {
+ err = ubifs_tnc_remove_ino(c, inode->i_ino);
+ if (err)
+ goto out_ro;
+ ubifs_delete_orphan(c, inode->i_ino);
+ err = ubifs_add_dirt(c, lnum, len);
+ } else {
+ union ubifs_key key;
+
+ ino_key_init(c, &key, inode->i_ino);
+ err = ubifs_tnc_add(c, &key, lnum, offs, len);
+ }
+ if (err)
+ goto out_ro;
+
+ finish_reservation(c);
+ spin_lock(&ui->ui_lock);
+ ui->synced_i_size = ui->ui_size;
+ spin_unlock(&ui->ui_lock);
+ kfree(ino);
+ return 0;
+
+out_release:
+ release_head(c, BASEHD);
+out_ro:
+ ubifs_ro_mode(c, err);
+ finish_reservation(c);
+out_free:
+ kfree(ino);
+ return err;
+}
+
+/**
+ * ubifs_jnl_rename - rename a directory entry.
+ * @c: UBIFS file-system description object
+ * @old_dir: parent inode of directory entry to rename
+ * @old_dentry: directory entry to rename
+ * @new_dir: parent inode of directory entry to rename
+ * @new_dentry: new directory entry (or directory entry to replace)
+ * @sync: non-zero if the write-buffer has to be synchronized
+ *
+ * This function implements the re-name operation which may involve writing up
+ * to 3 inodes and 2 directory entries. It marks the written inodes as clean
+ * and returns zero on success. In case of failure, a negative error code is
+ * returned.
+ */
+int ubifs_jnl_rename(struct ubifs_info *c, const struct inode *old_dir,
+ const struct dentry *old_dentry,
+ const struct inode *new_dir,
+ const struct dentry *new_dentry, int sync)
+{
+ void *p;
+ union ubifs_key key;
+ struct ubifs_dent_node *dent, *dent2;
+ int err, dlen1, dlen2, ilen, lnum, offs, len;
+ const struct inode *old_inode = old_dentry->d_inode;
+ const struct inode *new_inode = new_dentry->d_inode;
+ int aligned_dlen1, aligned_dlen2, plen = UBIFS_INO_NODE_SZ;
+ int last_reference = !!(new_inode && new_inode->i_nlink == 0);
+ int move = (old_dir != new_dir);
+ struct ubifs_inode *uninitialized_var(new_ui);
+
+ dbg_jnl("dent '%.*s' in dir ino %lu to dent '%.*s' in dir ino %lu",
+ old_dentry->d_name.len, old_dentry->d_name.name,
+ old_dir->i_ino, new_dentry->d_name.len,
+ new_dentry->d_name.name, new_dir->i_ino);
+ ubifs_assert(ubifs_inode(old_dir)->data_len == 0);
+ ubifs_assert(ubifs_inode(new_dir)->data_len == 0);
+ ubifs_assert(mutex_is_locked(&ubifs_inode(old_dir)->ui_mutex));
+ ubifs_assert(mutex_is_locked(&ubifs_inode(new_dir)->ui_mutex));
+
+ dlen1 = UBIFS_DENT_NODE_SZ + new_dentry->d_name.len + 1;
+ dlen2 = UBIFS_DENT_NODE_SZ + old_dentry->d_name.len + 1;
+ if (new_inode) {
+ new_ui = ubifs_inode(new_inode);
+ ubifs_assert(mutex_is_locked(&new_ui->ui_mutex));
+ ilen = UBIFS_INO_NODE_SZ;
+ if (!last_reference)
+ ilen += new_ui->data_len;
+ } else
+ ilen = 0;
+
+ aligned_dlen1 = ALIGN(dlen1, 8);
+ aligned_dlen2 = ALIGN(dlen2, 8);
+ len = aligned_dlen1 + aligned_dlen2 + ALIGN(ilen, 8) + ALIGN(plen, 8);
+ if (old_dir != new_dir)
+ len += plen;
+ dent = kmalloc(len, GFP_NOFS);
+ if (!dent)
+ return -ENOMEM;
+
+ /* Make reservation before allocating sequence numbers */
+ err = make_reservation(c, BASEHD, len);
+ if (err)
+ goto out_free;
+
+ /* Make new dent */
+ dent->ch.node_type = UBIFS_DENT_NODE;
+ dent_key_init_flash(c, &dent->key, new_dir->i_ino, &new_dentry->d_name);
+ dent->inum = cpu_to_le64(old_inode->i_ino);
+ dent->type = get_dent_type(old_inode->i_mode);
+ dent->nlen = cpu_to_le16(new_dentry->d_name.len);
+ memcpy(dent->name, new_dentry->d_name.name, new_dentry->d_name.len);
+ dent->name[new_dentry->d_name.len] = '\0';
+ zero_dent_node_unused(dent);
+ ubifs_prep_grp_node(c, dent, dlen1, 0);
+
+ /* Make deletion dent */
+ dent2 = (void *)dent + aligned_dlen1;
+ dent2->ch.node_type = UBIFS_DENT_NODE;
+ dent_key_init_flash(c, &dent2->key, old_dir->i_ino,
+ &old_dentry->d_name);
+ dent2->inum = 0;
+ dent2->type = DT_UNKNOWN;
+ dent2->nlen = cpu_to_le16(old_dentry->d_name.len);
+ memcpy(dent2->name, old_dentry->d_name.name, old_dentry->d_name.len);
+ dent2->name[old_dentry->d_name.len] = '\0';
+ zero_dent_node_unused(dent2);
+ ubifs_prep_grp_node(c, dent2, dlen2, 0);
+
+ p = (void *)dent2 + aligned_dlen2;
+ if (new_inode) {
+ pack_inode(c, p, new_inode, 0, last_reference);
+ p += ALIGN(ilen, 8);
+ }
+
+ if (!move)
+ pack_inode(c, p, old_dir, 1, 0);
+ else {
+ pack_inode(c, p, old_dir, 0, 0);
+ p += ALIGN(plen, 8);
+ pack_inode(c, p, new_dir, 1, 0);
+ }
+
+ if (last_reference) {
+ err = ubifs_add_orphan(c, new_inode->i_ino);
+ if (err) {
+ release_head(c, BASEHD);
+ goto out_finish;
+ }
+ }
+
+ err = write_head(c, BASEHD, dent, len, &lnum, &offs, sync);
+ if (err)
+ goto out_release;
+ if (!sync) {
+ struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
+
+ ubifs_wbuf_add_ino_nolock(wbuf, new_dir->i_ino);
+ ubifs_wbuf_add_ino_nolock(wbuf, old_dir->i_ino);
+ if (new_inode)
+ ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf,
+ new_inode->i_ino);
+ }
+ release_head(c, BASEHD);
+
+ dent_key_init(c, &key, new_dir->i_ino, &new_dentry->d_name);
+ err = ubifs_tnc_add_nm(c, &key, lnum, offs, dlen1, &new_dentry->d_name);
+ if (err)
+ goto out_ro;
+
+ err = ubifs_add_dirt(c, lnum, dlen2);
+ if (err)
+ goto out_ro;
+
+ dent_key_init(c, &key, old_dir->i_ino, &old_dentry->d_name);
+ err = ubifs_tnc_remove_nm(c, &key, &old_dentry->d_name);
+ if (err)
+ goto out_ro;
+
+ offs += aligned_dlen1 + aligned_dlen2;
+ if (new_inode) {
+ ino_key_init(c, &key, new_inode->i_ino);
+ err = ubifs_tnc_add(c, &key, lnum, offs, ilen);
+ if (err)
+ goto out_ro;
+ offs += ALIGN(ilen, 8);
+ }
+
+ ino_key_init(c, &key, old_dir->i_ino);
+ err = ubifs_tnc_add(c, &key, lnum, offs, plen);
+ if (err)
+ goto out_ro;
+
+ if (old_dir != new_dir) {
+ offs += ALIGN(plen, 8);
+ ino_key_init(c, &key, new_dir->i_ino);
+ err = ubifs_tnc_add(c, &key, lnum, offs, plen);
+ if (err)
+ goto out_ro;
+ }
+
+ finish_reservation(c);
+ if (new_inode) {
+ mark_inode_clean(c, new_ui);
+ spin_lock(&new_ui->ui_lock);
+ new_ui->synced_i_size = new_ui->ui_size;
+ spin_unlock(&new_ui->ui_lock);
+ }
+ mark_inode_clean(c, ubifs_inode(old_dir));
+ if (move)
+ mark_inode_clean(c, ubifs_inode(new_dir));
+ kfree(dent);
+ return 0;
+
+out_release:
+ release_head(c, BASEHD);
+out_ro:
+ ubifs_ro_mode(c, err);
+ if (last_reference)
+ ubifs_delete_orphan(c, new_inode->i_ino);
+out_finish:
+ finish_reservation(c);
+out_free:
+ kfree(dent);
+ return err;
+}
+
+/**
+ * recomp_data_node - re-compress a truncated data node.
+ * @dn: data node to re-compress
+ * @new_len: new length
+ *
+ * This function is used when an inode is truncated and the last data node of
+ * the inode has to be re-compressed and re-written.
+ */
+static int recomp_data_node(struct ubifs_data_node *dn, int *new_len)
+{
+ void *buf;
+ int err, len, compr_type, out_len;
+
+ out_len = le32_to_cpu(dn->size);
+ buf = kmalloc(out_len * WORST_COMPR_FACTOR, GFP_NOFS);
+ if (!buf)
+ return -ENOMEM;
+
+ len = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ;
+ compr_type = le16_to_cpu(dn->compr_type);
+ err = ubifs_decompress(&dn->data, len, buf, &out_len, compr_type);
+ if (err)
+ goto out;
+
+ ubifs_compress(buf, *new_len, &dn->data, &out_len, &compr_type);
+ ubifs_assert(out_len <= UBIFS_BLOCK_SIZE);
+ dn->compr_type = cpu_to_le16(compr_type);
+ dn->size = cpu_to_le32(*new_len);
+ *new_len = UBIFS_DATA_NODE_SZ + out_len;
+out:
+ kfree(buf);
+ return err;
+}
+
+/**
+ * ubifs_jnl_truncate - update the journal for a truncation.
+ * @c: UBIFS file-system description object
+ * @inode: inode to truncate
+ * @old_size: old size
+ * @new_size: new size
+ *
+ * When the size of a file decreases due to truncation, a truncation node is
+ * written, the journal tree is updated, and the last data block is re-written
+ * if it has been affected. The inode is also updated in order to synchronize
+ * the new inode size.
+ *
+ * This function marks the inode as clean and returns zero on success. In case
+ * of failure, a negative error code is returned.
+ */
+int ubifs_jnl_truncate(struct ubifs_info *c, const struct inode *inode,
+ loff_t old_size, loff_t new_size)
+{
+ union ubifs_key key, to_key;
+ struct ubifs_ino_node *ino;
+ struct ubifs_trun_node *trun;
+ struct ubifs_data_node *uninitialized_var(dn);
+ int err, dlen, len, lnum, offs, bit, sz, sync = IS_SYNC(inode);
+ struct ubifs_inode *ui = ubifs_inode(inode);
+ ino_t inum = inode->i_ino;
+ unsigned int blk;
+
+ dbg_jnl("ino %lu, size %lld -> %lld", inum, old_size, new_size);
+ ubifs_assert(!ui->data_len);
+ ubifs_assert(S_ISREG(inode->i_mode));
+ ubifs_assert(mutex_is_locked(&ui->ui_mutex));
+
+ sz = UBIFS_TRUN_NODE_SZ + UBIFS_INO_NODE_SZ +
+ UBIFS_MAX_DATA_NODE_SZ * WORST_COMPR_FACTOR;
+ ino = kmalloc(sz, GFP_NOFS);
+ if (!ino)
+ return -ENOMEM;
+
+ trun = (void *)ino + UBIFS_INO_NODE_SZ;
+ trun->ch.node_type = UBIFS_TRUN_NODE;
+ trun->inum = cpu_to_le32(inum);
+ trun->old_size = cpu_to_le64(old_size);
+ trun->new_size = cpu_to_le64(new_size);
+ zero_trun_node_unused(trun);
+
+ dlen = new_size & (UBIFS_BLOCK_SIZE - 1);
+ if (dlen) {
+ /* Get last data block so it can be truncated */
+ dn = (void *)trun + UBIFS_TRUN_NODE_SZ;
+ blk = new_size >> UBIFS_BLOCK_SHIFT;
+ data_key_init(c, &key, inum, blk);
+ dbg_jnl("last block key %s", DBGKEY(&key));
+ err = ubifs_tnc_lookup(c, &key, dn);
+ if (err == -ENOENT)
+ dlen = 0; /* Not found (so it is a hole) */
+ else if (err)
+ goto out_free;
+ else {
+ if (le32_to_cpu(dn->size) <= dlen)
+ dlen = 0; /* Nothing to do */
+ else {
+ int compr_type = le16_to_cpu(dn->compr_type);
+
+ if (compr_type != UBIFS_COMPR_NONE) {
+ err = recomp_data_node(dn, &dlen);
+ if (err)
+ goto out_free;
+ } else {
+ dn->size = cpu_to_le32(dlen);
+ dlen += UBIFS_DATA_NODE_SZ;
+ }
+ zero_data_node_unused(dn);
+ }
+ }
+ }
+
+ /* Must make reservation before allocating sequence numbers */
+ len = UBIFS_TRUN_NODE_SZ + UBIFS_INO_NODE_SZ;
+ if (dlen)
+ len += dlen;
+ err = make_reservation(c, BASEHD, len);
+ if (err)
+ goto out_free;
+
+ pack_inode(c, ino, inode, 0, 0);
+ ubifs_prep_grp_node(c, trun, UBIFS_TRUN_NODE_SZ, dlen ? 0 : 1);
+ if (dlen)
+ ubifs_prep_grp_node(c, dn, dlen, 1);
+
+ err = write_head(c, BASEHD, ino, len, &lnum, &offs, sync);
+ if (err)
+ goto out_release;
+ if (!sync)
+ ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, inum);
+ release_head(c, BASEHD);
+
+ if (dlen) {
+ sz = offs + UBIFS_INO_NODE_SZ + UBIFS_TRUN_NODE_SZ;
+ err = ubifs_tnc_add(c, &key, lnum, sz, dlen);
+ if (err)
+ goto out_ro;
+ }
+
+ ino_key_init(c, &key, inum);
+ err = ubifs_tnc_add(c, &key, lnum, offs, UBIFS_INO_NODE_SZ);
+ if (err)
+ goto out_ro;
+
+ err = ubifs_add_dirt(c, lnum, UBIFS_TRUN_NODE_SZ);
+ if (err)
+ goto out_ro;
+
+ bit = new_size & (UBIFS_BLOCK_SIZE - 1);
+ blk = (new_size >> UBIFS_BLOCK_SHIFT) + (bit ? 1 : 0);
+ data_key_init(c, &key, inum, blk);
+
+ bit = old_size & (UBIFS_BLOCK_SIZE - 1);
+ blk = (old_size >> UBIFS_BLOCK_SHIFT) - (bit ? 0: 1);
+ data_key_init(c, &to_key, inum, blk);
+
+ err = ubifs_tnc_remove_range(c, &key, &to_key);
+ if (err)
+ goto out_ro;
+
+ finish_reservation(c);
+ spin_lock(&ui->ui_lock);
+ ui->synced_i_size = ui->ui_size;
+ spin_unlock(&ui->ui_lock);
+ mark_inode_clean(c, ui);
+ kfree(ino);
+ return 0;
+
+out_release:
+ release_head(c, BASEHD);
+out_ro:
+ ubifs_ro_mode(c, err);
+ finish_reservation(c);
+out_free:
+ kfree(ino);
+ return err;
+}
+
+#ifdef CONFIG_UBIFS_FS_XATTR
+
+/**
+ * ubifs_jnl_delete_xattr - delete an extended attribute.
+ * @c: UBIFS file-system description object
+ * @host: host inode
+ * @inode: extended attribute inode
+ * @nm: extended attribute entry name
+ *
+ * This function delete an extended attribute which is very similar to
+ * un-linking regular files - it writes a deletion xentry, a deletion inode and
+ * updates the target inode. Returns zero in case of success and a negative
+ * error code in case of failure.
+ */
+int ubifs_jnl_delete_xattr(struct ubifs_info *c, const struct inode *host,
+ const struct inode *inode, const struct qstr *nm)
+{
+ int err, xlen, hlen, len, lnum, xent_offs, aligned_xlen;
+ struct ubifs_dent_node *xent;
+ struct ubifs_ino_node *ino;
+ union ubifs_key xent_key, key1, key2;
+ int sync = IS_DIRSYNC(host);
+ struct ubifs_inode *host_ui = ubifs_inode(host);
+
+ dbg_jnl("host %lu, xattr ino %lu, name '%s', data len %d",
+ host->i_ino, inode->i_ino, nm->name,
+ ubifs_inode(inode)->data_len);
+ ubifs_assert(inode->i_nlink == 0);
+ ubifs_assert(mutex_is_locked(&host_ui->ui_mutex));
+
+ /*
+ * Since we are deleting the inode, we do not bother to attach any data
+ * to it and assume its length is %UBIFS_INO_NODE_SZ.
+ */
+ xlen = UBIFS_DENT_NODE_SZ + nm->len + 1;
+ aligned_xlen = ALIGN(xlen, 8);
+ hlen = host_ui->data_len + UBIFS_INO_NODE_SZ;
+ len = aligned_xlen + UBIFS_INO_NODE_SZ + ALIGN(hlen, 8);
+
+ xent = kmalloc(len, GFP_NOFS);
+ if (!xent)
+ return -ENOMEM;
+
+ /* Make reservation before allocating sequence numbers */
+ err = make_reservation(c, BASEHD, len);
+ if (err) {
+ kfree(xent);
+ return err;
+ }
+
+ xent->ch.node_type = UBIFS_XENT_NODE;
+ xent_key_init(c, &xent_key, host->i_ino, nm);
+ key_write(c, &xent_key, xent->key);
+ xent->inum = 0;
+ xent->type = get_dent_type(inode->i_mode);
+ xent->nlen = cpu_to_le16(nm->len);
+ memcpy(xent->name, nm->name, nm->len);
+ xent->name[nm->len] = '\0';
+ zero_dent_node_unused(xent);
+ ubifs_prep_grp_node(c, xent, xlen, 0);
+
+ ino = (void *)xent + aligned_xlen;
+ pack_inode(c, ino, inode, 0, 1);
+ ino = (void *)ino + UBIFS_INO_NODE_SZ;
+ pack_inode(c, ino, host, 1, 0);
+
+ err = write_head(c, BASEHD, xent, len, &lnum, &xent_offs, sync);
+ if (!sync && !err)
+ ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, host->i_ino);
+ release_head(c, BASEHD);
+ kfree(xent);
+ if (err)
+ goto out_ro;
+
+ /* Remove the extended attribute entry from TNC */
+ err = ubifs_tnc_remove_nm(c, &xent_key, nm);
+ if (err)
+ goto out_ro;
+ err = ubifs_add_dirt(c, lnum, xlen);
+ if (err)
+ goto out_ro;
+
+ /*
+ * Remove all nodes belonging to the extended attribute inode from TNC.
+ * Well, there actually must be only one node - the inode itself.
+ */
+ lowest_ino_key(c, &key1, inode->i_ino);
+ highest_ino_key(c, &key2, inode->i_ino);
+ err = ubifs_tnc_remove_range(c, &key1, &key2);
+ if (err)
+ goto out_ro;
+ err = ubifs_add_dirt(c, lnum, UBIFS_INO_NODE_SZ);
+ if (err)
+ goto out_ro;
+
+ /* And update TNC with the new host inode position */
+ ino_key_init(c, &key1, host->i_ino);
+ err = ubifs_tnc_add(c, &key1, lnum, xent_offs + len - hlen, hlen);
+ if (err)
+ goto out_ro;
+
+ finish_reservation(c);
+ spin_lock(&host_ui->ui_lock);
+ host_ui->synced_i_size = host_ui->ui_size;
+ spin_unlock(&host_ui->ui_lock);
+ mark_inode_clean(c, host_ui);
+ return 0;
+
+out_ro:
+ ubifs_ro_mode(c, err);
+ finish_reservation(c);
+ return err;
+}
+
+/**
+ * ubifs_jnl_change_xattr - change an extended attribute.
+ * @c: UBIFS file-system description object
+ * @inode: extended attribute inode
+ * @host: host inode
+ *
+ * This function writes the updated version of an extended attribute inode and
+ * the host inode tho the journal (to the base head). The host inode is written
+ * after the extended attribute inode in order to guarantee that the extended
+ * attribute will be flushed when the inode is synchronized by 'fsync()' and
+ * consequently, the write-buffer is synchronized. This function returns zero
+ * in case of success and a negative error code in case of failure.
+ */
+int ubifs_jnl_change_xattr(struct ubifs_info *c, const struct inode *inode,
+ const struct inode *host)
+{
+ int err, len1, len2, aligned_len, aligned_len1, lnum, offs;
+ struct ubifs_inode *host_ui = ubifs_inode(inode);
+ struct ubifs_ino_node *ino;
+ union ubifs_key key;
+ int sync = IS_DIRSYNC(host);
+
+ dbg_jnl("ino %lu, ino %lu", host->i_ino, inode->i_ino);
+ ubifs_assert(host->i_nlink > 0);
+ ubifs_assert(inode->i_nlink > 0);
+ ubifs_assert(mutex_is_locked(&host_ui->ui_mutex));
+
+ len1 = UBIFS_INO_NODE_SZ + host_ui->data_len;
+ len2 = UBIFS_INO_NODE_SZ + ubifs_inode(inode)->data_len;
+ aligned_len1 = ALIGN(len1, 8);
+ aligned_len = aligned_len1 + ALIGN(len2, 8);
+
+ ino = kmalloc(aligned_len, GFP_NOFS);
+ if (!ino)
+ return -ENOMEM;
+
+ /* Make reservation before allocating sequence numbers */
+ err = make_reservation(c, BASEHD, aligned_len);
+ if (err)
+ goto out_free;
+
+ pack_inode(c, ino, host, 0, 0);
+ pack_inode(c, (void *)ino + aligned_len1, inode, 1, 0);
+
+ err = write_head(c, BASEHD, ino, aligned_len, &lnum, &offs, 0);
+ if (!sync && !err) {
+ struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
+
+ ubifs_wbuf_add_ino_nolock(wbuf, host->i_ino);
+ ubifs_wbuf_add_ino_nolock(wbuf, inode->i_ino);
+ }
+ release_head(c, BASEHD);
+ if (err)
+ goto out_ro;
+
+ ino_key_init(c, &key, host->i_ino);
+ err = ubifs_tnc_add(c, &key, lnum, offs, len1);
+ if (err)
+ goto out_ro;
+
+ ino_key_init(c, &key, inode->i_ino);
+ err = ubifs_tnc_add(c, &key, lnum, offs + aligned_len1, len2);
+ if (err)
+ goto out_ro;
+
+ finish_reservation(c);
+ spin_lock(&host_ui->ui_lock);
+ host_ui->synced_i_size = host_ui->ui_size;
+ spin_unlock(&host_ui->ui_lock);
+ mark_inode_clean(c, host_ui);
+ kfree(ino);
+ return 0;
+
+out_ro:
+ ubifs_ro_mode(c, err);
+ finish_reservation(c);
+out_free:
+ kfree(ino);
+ return err;
+}
+
+#endif /* CONFIG_UBIFS_FS_XATTR */
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ * Adrian Hunter
+ */
+
+/*
+ * This header contains various key-related definitions and helper function.
+ * UBIFS allows several key schemes, so we access key fields only via these
+ * helpers. At the moment only one key scheme is supported.
+ *
+ * Simple key scheme
+ * ~~~~~~~~~~~~~~~~~
+ *
+ * Keys are 64-bits long. First 32-bits are inode number (parent inode number
+ * in case of direntry key). Next 3 bits are node type. The last 29 bits are
+ * 4KiB offset in case of inode node, and direntry hash in case of a direntry
+ * node. We use "r5" hash borrowed from reiserfs.
+ */
+
+#ifndef __UBIFS_KEY_H__
+#define __UBIFS_KEY_H__
+
+/**
+ * key_r5_hash - R5 hash function (borrowed from reiserfs).
+ * @s: direntry name
+ * @len: name length
+ */
+static inline uint32_t key_r5_hash(const char *s, int len)
+{
+ uint32_t a = 0;
+ const signed char *str = (const signed char *)s;
+
+ while (*str) {
+ a += *str << 4;
+ a += *str >> 4;
+ a *= 11;
+ str++;
+ }
+
+ a &= UBIFS_S_KEY_HASH_MASK;
+
+ /*
+ * We use hash values as offset in directories, so values %0 and %1 are
+ * reserved for "." and "..". %2 is reserved for "end of readdir"
+ * marker.
+ */
+ if (unlikely(a >= 0 && a <= 2))
+ a += 3;
+ return a;
+}
+
+/**
+ * key_test_hash - testing hash function.
+ * @str: direntry name
+ * @len: name length
+ */
+static inline uint32_t key_test_hash(const char *str, int len)
+{
+ uint32_t a = 0;
+
+ len = min_t(uint32_t, len, 4);
+ memcpy(&a, str, len);
+ a &= UBIFS_S_KEY_HASH_MASK;
+ if (unlikely(a >= 0 && a <= 2))
+ a += 3;
+ return a;
+}
+
+/**
+ * ino_key_init - initialize inode key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: inode number
+ */
+static inline void ino_key_init(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum)
+{
+ key->u32[0] = inum;
+ key->u32[1] = UBIFS_INO_KEY << UBIFS_S_KEY_BLOCK_BITS;
+}
+
+/**
+ * ino_key_init_flash - initialize on-flash inode key.
+ * @c: UBIFS file-system description object
+ * @k: key to initialize
+ * @inum: inode number
+ */
+static inline void ino_key_init_flash(const struct ubifs_info *c, void *k,
+ ino_t inum)
+{
+ union ubifs_key *key = k;
+
+ key->j32[0] = cpu_to_le32(inum);
+ key->j32[1] = cpu_to_le32(UBIFS_INO_KEY << UBIFS_S_KEY_BLOCK_BITS);
+ memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
+}
+
+/**
+ * lowest_ino_key - get the lowest possible inode key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: inode number
+ */
+static inline void lowest_ino_key(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum)
+{
+ key->u32[0] = inum;
+ key->u32[1] = 0;
+}
+
+/**
+ * highest_ino_key - get the highest possible inode key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: inode number
+ */
+static inline void highest_ino_key(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum)
+{
+ key->u32[0] = inum;
+ key->u32[1] = 0xffffffff;
+}
+
+/**
+ * dent_key_init - initialize directory entry key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: parent inode number
+ * @nm: direntry name and length
+ */
+static inline void dent_key_init(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum,
+ const struct qstr *nm)
+{
+ uint32_t hash = c->key_hash(nm->name, nm->len);
+
+ ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+ key->u32[0] = inum;
+ key->u32[1] = hash | (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS);
+}
+
+/**
+ * dent_key_init_hash - initialize directory entry key without re-calculating
+ * hash function.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: parent inode number
+ * @hash: direntry name hash
+ */
+static inline void dent_key_init_hash(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum,
+ uint32_t hash)
+{
+ ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+ key->u32[0] = inum;
+ key->u32[1] = hash | (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS);
+}
+
+/**
+ * dent_key_init_flash - initialize on-flash directory entry key.
+ * @c: UBIFS file-system description object
+ * @k: key to initialize
+ * @inum: parent inode number
+ * @nm: direntry name and length
+ */
+static inline void dent_key_init_flash(const struct ubifs_info *c, void *k,
+ ino_t inum, const struct qstr *nm)
+{
+ union ubifs_key *key = k;
+ uint32_t hash = c->key_hash(nm->name, nm->len);
+
+ ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+ key->j32[0] = cpu_to_le32(inum);
+ key->j32[1] = cpu_to_le32(hash |
+ (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS));
+ memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
+}
+
+/**
+ * lowest_dent_key - get the lowest possible directory entry key.
+ * @c: UBIFS file-system description object
+ * @key: where to store the lowest key
+ * @inum: parent inode number
+ */
+static inline void lowest_dent_key(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum)
+{
+ key->u32[0] = inum;
+ key->u32[1] = UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS;
+}
+
+/**
+ * xent_key_init - initialize extended attribute entry key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: host inode number
+ * @nm: extended attribute entry name and length
+ */
+static inline void xent_key_init(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum,
+ const struct qstr *nm)
+{
+ uint32_t hash = c->key_hash(nm->name, nm->len);
+
+ ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+ key->u32[0] = inum;
+ key->u32[1] = hash | (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS);
+}
+
+/**
+ * xent_key_init_hash - initialize extended attribute entry key without
+ * re-calculating hash function.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: host inode number
+ * @hash: extended attribute entry name hash
+ */
+static inline void xent_key_init_hash(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum,
+ uint32_t hash)
+{
+ ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+ key->u32[0] = inum;
+ key->u32[1] = hash | (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS);
+}
+
+/**
+ * xent_key_init_flash - initialize on-flash extended attribute entry key.
+ * @c: UBIFS file-system description object
+ * @k: key to initialize
+ * @inum: host inode number
+ * @nm: extended attribute entry name and length
+ */
+static inline void xent_key_init_flash(const struct ubifs_info *c, void *k,
+ ino_t inum, const struct qstr *nm)
+{
+ union ubifs_key *key = k;
+ uint32_t hash = c->key_hash(nm->name, nm->len);
+
+ ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+ key->j32[0] = cpu_to_le32(inum);
+ key->j32[1] = cpu_to_le32(hash |
+ (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS));
+ memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
+}
+
+/**
+ * lowest_xent_key - get the lowest possible extended attribute entry key.
+ * @c: UBIFS file-system description object
+ * @key: where to store the lowest key
+ * @inum: host inode number
+ */
+static inline void lowest_xent_key(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum)
+{
+ key->u32[0] = inum;
+ key->u32[1] = UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS;
+}
+
+/**
+ * data_key_init - initialize data key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: inode number
+ * @block: block number
+ */
+static inline void data_key_init(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum,
+ unsigned int block)
+{
+ ubifs_assert(!(block & ~UBIFS_S_KEY_BLOCK_MASK));
+ key->u32[0] = inum;
+ key->u32[1] = block | (UBIFS_DATA_KEY << UBIFS_S_KEY_BLOCK_BITS);
+}
+
+/**
+ * data_key_init_flash - initialize on-flash data key.
+ * @c: UBIFS file-system description object
+ * @k: key to initialize
+ * @inum: inode number
+ * @block: block number
+ */
+static inline void data_key_init_flash(const struct ubifs_info *c, void *k,
+ ino_t inum, unsigned int block)
+{
+ union ubifs_key *key = k;
+
+ ubifs_assert(!(block & ~UBIFS_S_KEY_BLOCK_MASK));
+ key->j32[0] = cpu_to_le32(inum);
+ key->j32[1] = cpu_to_le32(block |
+ (UBIFS_DATA_KEY << UBIFS_S_KEY_BLOCK_BITS));
+ memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
+}
+
+/**
+ * trun_key_init - initialize truncation node key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: inode number
+ *
+ * Note, UBIFS does not have truncation keys on the media and this function is
+ * only used for purposes of replay.
+ */
+static inline void trun_key_init(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum)
+{
+ key->u32[0] = inum;
+ key->u32[1] = UBIFS_TRUN_KEY << UBIFS_S_KEY_BLOCK_BITS;
+}
+
+/**
+ * key_type - get key type.
+ * @c: UBIFS file-system description object
+ * @key: key to get type of
+ */
+static inline int key_type(const struct ubifs_info *c,
+ const union ubifs_key *key)
+{
+ return key->u32[1] >> UBIFS_S_KEY_BLOCK_BITS;
+}
+
+/**
+ * key_type_flash - get type of a on-flash formatted key.
+ * @c: UBIFS file-system description object
+ * @k: key to get type of
+ */
+static inline int key_type_flash(const struct ubifs_info *c, const void *k)
+{
+ const union ubifs_key *key = k;
+
+ return le32_to_cpu(key->u32[1]) >> UBIFS_S_KEY_BLOCK_BITS;
+}
+
+/**
+ * key_inum - fetch inode number from key.
+ * @c: UBIFS file-system description object
+ * @k: key to fetch inode number from
+ */
+static inline ino_t key_inum(const struct ubifs_info *c, const void *k)
+{
+ const union ubifs_key *key = k;
+
+ return key->u32[0];
+}
+
+/**
+ * key_inum_flash - fetch inode number from an on-flash formatted key.
+ * @c: UBIFS file-system description object
+ * @k: key to fetch inode number from
+ */
+static inline ino_t key_inum_flash(const struct ubifs_info *c, const void *k)
+{
+ const union ubifs_key *key = k;
+
+ return le32_to_cpu(key->j32[0]);
+}
+
+/**
+ * key_hash - get directory entry hash.
+ * @c: UBIFS file-system description object
+ * @key: the key to get hash from
+ */
+static inline int key_hash(const struct ubifs_info *c,
+ const union ubifs_key *key)
+{
+ return key->u32[1] & UBIFS_S_KEY_HASH_MASK;
+}
+
+/**
+ * key_hash_flash - get directory entry hash from an on-flash formatted key.
+ * @c: UBIFS file-system description object
+ * @k: the key to get hash from
+ */
+static inline int key_hash_flash(const struct ubifs_info *c, const void *k)
+{
+ const union ubifs_key *key = k;
+
+ return le32_to_cpu(key->j32[1]) & UBIFS_S_KEY_HASH_MASK;
+}
+
+/**
+ * key_block - get data block number.
+ * @c: UBIFS file-system description object
+ * @key: the key to get the block number from
+ */
+static inline unsigned int key_block(const struct ubifs_info *c,
+ const union ubifs_key *key)
+{
+ return key->u32[1] & UBIFS_S_KEY_BLOCK_MASK;
+}
+
+/**
+ * key_block_flash - get data block number from an on-flash formatted key.
+ * @c: UBIFS file-system description object
+ * @k: the key to get the block number from
+ */
+static inline unsigned int key_block_flash(const struct ubifs_info *c,
+ const void *k)
+{
+ const union ubifs_key *key = k;
+
+ return le32_to_cpu(key->u32[1]) & UBIFS_S_KEY_BLOCK_MASK;
+}
+
+/**
+ * key_read - transform a key to in-memory format.
+ * @c: UBIFS file-system description object
+ * @from: the key to transform
+ * @to: the key to store the result
+ */
+static inline void key_read(const struct ubifs_info *c, const void *from,
+ union ubifs_key *to)
+{
+ const union ubifs_key *f = from;
+
+ to->u32[0] = le32_to_cpu(f->j32[0]);
+ to->u32[1] = le32_to_cpu(f->j32[1]);
+}
+
+/**
+ * key_write - transform a key from in-memory format.
+ * @c: UBIFS file-system description object
+ * @from: the key to transform
+ * @to: the key to store the result
+ */
+static inline void key_write(const struct ubifs_info *c,
+ const union ubifs_key *from, void *to)
+{
+ union ubifs_key *t = to;
+
+ t->j32[0] = cpu_to_le32(from->u32[0]);
+ t->j32[1] = cpu_to_le32(from->u32[1]);
+ memset(to + 8, 0, UBIFS_MAX_KEY_LEN - 8);
+}
+
+/**
+ * key_write_idx - transform a key from in-memory format for the index.
+ * @c: UBIFS file-system description object
+ * @from: the key to transform
+ * @to: the key to store the result
+ */
+static inline void key_write_idx(const struct ubifs_info *c,
+ const union ubifs_key *from, void *to)
+{
+ union ubifs_key *t = to;
+
+ t->j32[0] = cpu_to_le32(from->u32[0]);
+ t->j32[1] = cpu_to_le32(from->u32[1]);
+}
+
+/**
+ * key_copy - copy a key.
+ * @c: UBIFS file-system description object
+ * @from: the key to copy from
+ * @to: the key to copy to
+ */
+static inline void key_copy(const struct ubifs_info *c,
+ const union ubifs_key *from, union ubifs_key *to)
+{
+ to->u64[0] = from->u64[0];
+}
+
+/**
+ * keys_cmp - compare keys.
+ * @c: UBIFS file-system description object
+ * @key1: the first key to compare
+ * @key2: the second key to compare
+ *
+ * This function compares 2 keys and returns %-1 if @key1 is less than
+ * @key2, 0 if the keys are equivalent and %1 if @key1 is greater than @key2.
+ */
+static inline int keys_cmp(const struct ubifs_info *c,
+ const union ubifs_key *key1,
+ const union ubifs_key *key2)
+{
+ if (key1->u32[0] < key2->u32[0])
+ return -1;
+ if (key1->u32[0] > key2->u32[0])
+ return 1;
+ if (key1->u32[1] < key2->u32[1])
+ return -1;
+ if (key1->u32[1] > key2->u32[1])
+ return 1;
+
+ return 0;
+}
+
+/**
+ * is_hash_key - is a key vulnerable to hash collisions.
+ * @c: UBIFS file-system description object
+ * @key: key
+ *
+ * This function returns %1 if @key is a hashed key or %0 otherwise.
+ */
+static inline int is_hash_key(const struct ubifs_info *c,
+ const union ubifs_key *key)
+{
+ int type = key_type(c, key);
+
+ return type == UBIFS_DENT_KEY || type == UBIFS_XENT_KEY;
+}
+
+/**
+ * key_max_inode_size - get maximum file size allowed by current key format.
+ * @c: UBIFS file-system description object
+ */
+static inline unsigned long long key_max_inode_size(const struct ubifs_info *c)
+{
+ switch (c->key_fmt) {
+ case UBIFS_SIMPLE_KEY_FMT:
+ return (1ULL << UBIFS_S_KEY_BLOCK_BITS) * UBIFS_BLOCK_SIZE;
+ default:
+ return 0;
+ }
+}
+#endif /* !__UBIFS_KEY_H__ */
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ * Adrian Hunter
+ */
+
+/*
+ * This file is a part of UBIFS journal implementation and contains various
+ * functions which manipulate the log. The log is a fixed area on the flash
+ * which does not contain any data but refers to buds. The log is a part of the
+ * journal.
+ */
+
+#include "ubifs.h"
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+static int dbg_check_bud_bytes(struct ubifs_info *c);
+#else
+#define dbg_check_bud_bytes(c) 0
+#endif
+
+/**
+ * ubifs_search_bud - search bud LEB.
+ * @c: UBIFS file-system description object
+ * @lnum: logical eraseblock number to search
+ *
+ * This function searches bud LEB @lnum. Returns bud description object in case
+ * of success and %NULL if there is no bud with this LEB number.
+ */
+struct ubifs_bud *ubifs_search_bud(struct ubifs_info *c, int lnum)
+{
+ struct rb_node *p;
+ struct ubifs_bud *bud;
+
+ spin_lock(&c->buds_lock);
+ p = c->buds.rb_node;
+ while (p) {
+ bud = rb_entry(p, struct ubifs_bud, rb);
+ if (lnum < bud->lnum)
+ p = p->rb_left;
+ else if (lnum > bud->lnum)
+ p = p->rb_right;
+ else {
+ spin_unlock(&c->buds_lock);
+ return bud;
+ }
+ }
+ spin_unlock(&c->buds_lock);
+ return NULL;
+}
+
+/**
+ * ubifs_get_wbuf - get the wbuf associated with a LEB, if there is one.
+ * @c: UBIFS file-system description object
+ * @lnum: logical eraseblock number to search
+ *
+ * This functions returns the wbuf for @lnum or %NULL if there is not one.
+ */
+struct ubifs_wbuf *ubifs_get_wbuf(struct ubifs_info *c, int lnum)
+{
+ struct rb_node *p;
+ struct ubifs_bud *bud;
+ int jhead;
+
+ if (!c->jheads)
+ return NULL;
+
+ spin_lock(&c->buds_lock);
+ p = c->buds.rb_node;
+ while (p) {
+ bud = rb_entry(p, struct ubifs_bud, rb);
+ if (lnum < bud->lnum)
+ p = p->rb_left;
+ else if (lnum > bud->lnum)
+ p = p->rb_right;
+ else {
+ jhead = bud->jhead;
+ spin_unlock(&c->buds_lock);
+ return &c->jheads[jhead].wbuf;
+ }
+ }
+ spin_unlock(&c->buds_lock);
+ return NULL;
+}
+
+/**
+ * next_log_lnum - switch to the next log LEB.
+ * @c: UBIFS file-system description object
+ * @lnum: current log LEB
+ */
+static inline int next_log_lnum(const struct ubifs_info *c, int lnum)
+{
+ lnum += 1;
+ if (lnum > c->log_last)
+ lnum = UBIFS_LOG_LNUM;
+
+ return lnum;
+}
+
+/**
+ * empty_log_bytes - calculate amount of empty space in the log.
+ * @c: UBIFS file-system description object
+ */
+static inline long long empty_log_bytes(const struct ubifs_info *c)
+{
+ long long h, t;
+
+ h = (long long)c->lhead_lnum * c->leb_size + c->lhead_offs;
+ t = (long long)c->ltail_lnum * c->leb_size;
+
+ if (h >= t)
+ return c->log_bytes - h + t;
+ else
+ return t - h;
+}
+
+/**
+ * ubifs_add_bud - add bud LEB to the tree of buds and its journal head list.
+ * @c: UBIFS file-system description object
+ * @bud: the bud to add
+ */
+void ubifs_add_bud(struct ubifs_info *c, struct ubifs_bud *bud)
+{
+ struct rb_node **p, *parent = NULL;
+ struct ubifs_bud *b;
+ struct ubifs_jhead *jhead;
+
+ spin_lock(&c->buds_lock);
+ p = &c->buds.rb_node;
+ while (*p) {
+ parent = *p;
+ b = rb_entry(parent, struct ubifs_bud, rb);
+ ubifs_assert(bud->lnum != b->lnum);
+ if (bud->lnum < b->lnum)
+ p = &(*p)->rb_left;
+ else
+ p = &(*p)->rb_right;
+ }
+
+ rb_link_node(&bud->rb, parent, p);
+ rb_insert_color(&bud->rb, &c->buds);
+ if (c->jheads) {
+ jhead = &c->jheads[bud->jhead];
+ list_add_tail(&bud->list, &jhead->buds_list);
+ } else
+ ubifs_assert(c->replaying && (c->vfs_sb->s_flags & MS_RDONLY));
+
+ /*
+ * Note, although this is a new bud, we anyway account this space now,
+ * before any data has been written to it, because this is about to
+ * guarantee fixed mount time, and this bud will anyway be read and
+ * scanned.
+ */
+ c->bud_bytes += c->leb_size - bud->start;
+
+ dbg_log("LEB %d:%d, jhead %d, bud_bytes %lld", bud->lnum,
+ bud->start, bud->jhead, c->bud_bytes);
+ spin_unlock(&c->buds_lock);
+}
+
+/**
+ * ubifs_create_buds_lists - create journal head buds lists for remount rw.
+ * @c: UBIFS file-system description object
+ */
+void ubifs_create_buds_lists(struct ubifs_info *c)
+{
+ struct rb_node *p;
+
+ spin_lock(&c->buds_lock);
+ p = rb_first(&c->buds);
+ while (p) {
+ struct ubifs_bud *bud = rb_entry(p, struct ubifs_bud, rb);
+ struct ubifs_jhead *jhead = &c->jheads[bud->jhead];
+
+ list_add_tail(&bud->list, &jhead->buds_list);
+ p = rb_next(p);
+ }
+ spin_unlock(&c->buds_lock);
+}
+
+/**
+ * ubifs_add_bud_to_log - add a new bud to the log.
+ * @c: UBIFS file-system description object
+ * @jhead: journal head the bud belongs to
+ * @lnum: LEB number of the bud
+ * @offs: starting offset of the bud
+ *
+ * This function writes reference node for the new bud LEB @lnum it to the log,
+ * and adds it to the buds tress. It also makes sure that log size does not
+ * exceed the 'c->max_bud_bytes' limit. Returns zero in case of success,
+ * %-EAGAIN if commit is required, and a negative error codes in case of
+ * failure.
+ */
+int ubifs_add_bud_to_log(struct ubifs_info *c, int jhead, int lnum, int offs)
+{
+ int err;
+ struct ubifs_bud *bud;
+ struct ubifs_ref_node *ref;
+
+ bud = kmalloc(sizeof(struct ubifs_bud), GFP_NOFS);
+ if (!bud)
+ return -ENOMEM;
+ ref = kzalloc(c->ref_node_alsz, GFP_NOFS);
+ if (!ref) {
+ kfree(bud);
+ return -ENOMEM;
+ }
+
+ mutex_lock(&c->log_mutex);
+
+ if (c->ro_media) {
+ err = -EROFS;
+ goto out_unlock;
+ }
+
+ /* Make sure we have enough space in the log */
+ if (empty_log_bytes(c) - c->ref_node_alsz < c->min_log_bytes) {
+ dbg_log("not enough log space - %lld, required %d",
+ empty_log_bytes(c), c->min_log_bytes);
+ ubifs_commit_required(c);
+ err = -EAGAIN;
+ goto out_unlock;
+ }
+
+ /*
+ * Make sure the the amount of space in buds will not exceed
+ * 'c->max_bud_bytes' limit, because we want to guarantee mount time
+ * limits.
+ *
+ * It is not necessary to hold @c->buds_lock when reading @c->bud_bytes
+ * because we are holding @c->log_mutex. All @c->bud_bytes take place
+ * when both @c->log_mutex and @c->bud_bytes are locked.
+ */
+ if (c->bud_bytes + c->leb_size - offs > c->max_bud_bytes) {
+ dbg_log("bud bytes %lld (%lld max), require commit",
+ c->bud_bytes, c->max_bud_bytes);
+ ubifs_commit_required(c);
+ err = -EAGAIN;
+ goto out_unlock;
+ }
+
+ /*
+ * If the journal is full enough - start background commit. Note, it is
+ * OK to read 'c->cmt_state' without spinlock because integer reads
+ * are atomic in the kernel.
+ */
+ if (c->bud_bytes >= c->bg_bud_bytes &&
+ c->cmt_state == COMMIT_RESTING) {
+ dbg_log("bud bytes %lld (%lld max), initiate BG commit",
+ c->bud_bytes, c->max_bud_bytes);
+ ubifs_request_bg_commit(c);
+ }
+
+ bud->lnum = lnum;
+ bud->start = offs;
+ bud->jhead = jhead;
+
+ ref->ch.node_type = UBIFS_REF_NODE;
+ ref->lnum = cpu_to_le32(bud->lnum);
+ ref->offs = cpu_to_le32(bud->start);
+ ref->jhead = cpu_to_le32(jhead);
+
+ if (c->lhead_offs > c->leb_size - c->ref_node_alsz) {
+ c->lhead_lnum = next_log_lnum(c, c->lhead_lnum);
+ c->lhead_offs = 0;
+ }
+
+ if (c->lhead_offs == 0) {
+ /* Must ensure next log LEB has been unmapped */
+ err = ubifs_leb_unmap(c, c->lhead_lnum);
+ if (err)
+ goto out_unlock;
+ }
+
+ if (bud->start == 0) {
+ /*
+ * Before writing the LEB reference which refers an empty LEB
+ * to the log, we have to make sure it is mapped, because
+ * otherwise we'd risk to refer an LEB with garbage in case of
+ * an unclean reboot, because the target LEB might have been
+ * unmapped, but not yet physically erased.
+ */
+ err = ubi_leb_map(c->ubi, bud->lnum, UBI_SHORTTERM);
+ if (err)
+ goto out_unlock;
+ }
+
+ dbg_log("write ref LEB %d:%d",
+ c->lhead_lnum, c->lhead_offs);
+ err = ubifs_write_node(c, ref, UBIFS_REF_NODE_SZ, c->lhead_lnum,
+ c->lhead_offs, UBI_SHORTTERM);
+ if (err)
+ goto out_unlock;
+
+ c->lhead_offs += c->ref_node_alsz;
+
+ ubifs_add_bud(c, bud);
+
+ mutex_unlock(&c->log_mutex);
+ kfree(ref);
+ return 0;
+
+out_unlock:
+ mutex_unlock(&c->log_mutex);
+ kfree(ref);
+ kfree(bud);
+ return err;
+}
+
+/**
+ * remove_buds - remove used buds.
+ * @c: UBIFS file-system description object
+ *
+ * This function removes use buds from the buds tree. It does not remove the
+ * buds which are pointed to by journal heads.
+ */
+static void remove_buds(struct ubifs_info *c)
+{
+ struct rb_node *p;
+
+ ubifs_assert(list_empty(&c->old_buds));
+ c->cmt_bud_bytes = 0;
+ spin_lock(&c->buds_lock);
+ p = rb_first(&c->buds);
+ while (p) {
+ struct rb_node *p1 = p;
+ struct ubifs_bud *bud;
+ struct ubifs_wbuf *wbuf;
+
+ p = rb_next(p);
+ bud = rb_entry(p1, struct ubifs_bud, rb);
+ wbuf = &c->jheads[bud->jhead].wbuf;
+
+ if (wbuf->lnum == bud->lnum) {
+ /*
+ * Do not remove buds which are pointed to by journal
+ * heads (non-closed buds).
+ */
+ c->cmt_bud_bytes += wbuf->offs - bud->start;
+ dbg_log("preserve %d:%d, jhead %d, bud bytes %d, "
+ "cmt_bud_bytes %lld", bud->lnum, bud->start,
+ bud->jhead, wbuf->offs - bud->start,
+ c->cmt_bud_bytes);
+ bud->start = wbuf->offs;
+ } else {
+ c->cmt_bud_bytes += c->leb_size - bud->start;
+ dbg_log("remove %d:%d, jhead %d, bud bytes %d, "
+ "cmt_bud_bytes %lld", bud->lnum, bud->start,
+ bud->jhead, c->leb_size - bud->start,
+ c->cmt_bud_bytes);
+ rb_erase(p1, &c->buds);
+ list_del(&bud->list);
+ /*
+ * If the commit does not finish, the recovery will need
+ * to replay the journal, in which case the old buds
+ * must be unchanged. Do not release them until post
+ * commit i.e. do not allow them to be garbage
+ * collected.
+ */
+ list_add(&bud->list, &c->old_buds);
+ }
+ }
+ spin_unlock(&c->buds_lock);
+}
+
+/**
+ * ubifs_log_start_commit - start commit.
+ * @c: UBIFS file-system description object
+ * @ltail_lnum: return new log tail LEB number
+ *
+ * The commit operation starts with writing "commit start" node to the log and
+ * reference nodes for all journal heads which will define new journal after
+ * the commit has been finished. The commit start and reference nodes are
+ * written in one go to the nearest empty log LEB (hence, when commit is
+ * finished UBIFS may safely unmap all the previous log LEBs). This function
+ * returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+int ubifs_log_start_commit(struct ubifs_info *c, int *ltail_lnum)
+{
+ void *buf;
+ struct ubifs_cs_node *cs;
+ struct ubifs_ref_node *ref;
+ int err, i, max_len, len;
+
+ err = dbg_check_bud_bytes(c);
+ if (err)
+ return err;
+
+ max_len = UBIFS_CS_NODE_SZ + c->jhead_cnt * UBIFS_REF_NODE_SZ;
+ max_len = ALIGN(max_len, c->min_io_size);
+ buf = cs = kmalloc(max_len, GFP_NOFS);
+ if (!buf)
+ return -ENOMEM;
+
+ cs->ch.node_type = UBIFS_CS_NODE;
+ cs->cmt_no = cpu_to_le64(c->cmt_no + 1);
+ ubifs_prepare_node(c, cs, UBIFS_CS_NODE_SZ, 0);
+
+ /*
+ * Note, we do not lock 'c->log_mutex' because this is the commit start
+ * phase and we are exclusively using the log. And we do not lock
+ * write-buffer because nobody can write to the file-system at this
+ * phase.
+ */
+
+ len = UBIFS_CS_NODE_SZ;
+ for (i = 0; i < c->jhead_cnt; i++) {
+ int lnum = c->jheads[i].wbuf.lnum;
+ int offs = c->jheads[i].wbuf.offs;
+
+ if (lnum == -1 || offs == c->leb_size)
+ continue;
+
+ dbg_log("add ref to LEB %d:%d for jhead %d", lnum, offs, i);
+ ref = buf + len;
+ ref->ch.node_type = UBIFS_REF_NODE;
+ ref->lnum = cpu_to_le32(lnum);
+ ref->offs = cpu_to_le32(offs);
+ ref->jhead = cpu_to_le32(i);
+
+ ubifs_prepare_node(c, ref, UBIFS_REF_NODE_SZ, 0);
+ len += UBIFS_REF_NODE_SZ;
+ }
+
+ ubifs_pad(c, buf + len, ALIGN(len, c->min_io_size) - len);
+
+ /* Switch to the next log LEB */
+ if (c->lhead_offs) {
+ c->lhead_lnum = next_log_lnum(c, c->lhead_lnum);
+ c->lhead_offs = 0;
+ }
+
+ if (c->lhead_offs == 0) {
+ /* Must ensure next LEB has been unmapped */
+ err = ubifs_leb_unmap(c, c->lhead_lnum);
+ if (err)
+ goto out;
+ }
+
+ len = ALIGN(len, c->min_io_size);
+ dbg_log("writing commit start at LEB %d:0, len %d", c->lhead_lnum, len);
+ err = ubifs_leb_write(c, c->lhead_lnum, cs, 0, len, UBI_SHORTTERM);
+ if (err)
+ goto out;
+
+ *ltail_lnum = c->lhead_lnum;
+
+ c->lhead_offs += len;
+ if (c->lhead_offs == c->leb_size) {
+ c->lhead_lnum = next_log_lnum(c, c->lhead_lnum);
+ c->lhead_offs = 0;
+ }
+
+ remove_buds(c);
+
+ /*
+ * We have started the commit and now users may use the rest of the log
+ * for new writes.
+ */
+ c->min_log_bytes = 0;
+
+out:
+ kfree(buf);
+ return err;
+}
+
+/**
+ * ubifs_log_end_commit - end commit.
+ * @c: UBIFS file-system description object
+ * @ltail_lnum: new log tail LEB number
+ *
+ * This function is called on when the commit operation was finished. It
+ * moves log tail to new position and unmaps LEBs which contain obsolete data.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+int ubifs_log_end_commit(struct ubifs_info *c, int ltail_lnum)
+{
+ int err;
+
+ /*
+ * At this phase we have to lock 'c->log_mutex' because UBIFS allows FS
+ * writes during commit. Its only short "commit" start phase when
+ * writers are blocked.
+ */
+ mutex_lock(&c->log_mutex);
+
+ dbg_log("old tail was LEB %d:0, new tail is LEB %d:0",
+ c->ltail_lnum, ltail_lnum);
+
+ c->ltail_lnum = ltail_lnum;
+ /*
+ * The commit is finished and from now on it must be guaranteed that
+ * there is always enough space for the next commit.
+ */
+ c->min_log_bytes = c->leb_size;
+
+ spin_lock(&c->buds_lock);
+ c->bud_bytes -= c->cmt_bud_bytes;
+ spin_unlock(&c->buds_lock);
+
+ err = dbg_check_bud_bytes(c);
+
+ mutex_unlock(&c->log_mutex);
+ return err;
+}
+
+/**
+ * ubifs_log_post_commit - things to do after commit is completed.
+ * @c: UBIFS file-system description object
+ * @old_ltail_lnum: old log tail LEB number
+ *
+ * Release buds only after commit is completed, because they must be unchanged
+ * if recovery is needed.
+ *
+ * Unmap log LEBs only after commit is completed, because they may be needed for
+ * recovery.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_log_post_commit(struct ubifs_info *c, int old_ltail_lnum)
+{
+ int lnum, err = 0;
+
+ while (!list_empty(&c->old_buds)) {
+ struct ubifs_bud *bud;
+
+ bud = list_entry(c->old_buds.next, struct ubifs_bud, list);
+ err = ubifs_return_leb(c, bud->lnum);
+ if (err)
+ return err;
+ list_del(&bud->list);
+ kfree(bud);
+ }
+ mutex_lock(&c->log_mutex);
+ for (lnum = old_ltail_lnum; lnum != c->ltail_lnum;
+ lnum = next_log_lnum(c, lnum)) {
+ dbg_log("unmap log LEB %d", lnum);
+ err = ubifs_leb_unmap(c, lnum);
+ if (err)
+ goto out;
+ }
+out:
+ mutex_unlock(&c->log_mutex);
+ return err;
+}
+
+/**
+ * struct done_ref - references that have been done.
+ * @rb: rb-tree node
+ * @lnum: LEB number
+ */
+struct done_ref {
+ struct rb_node rb;
+ int lnum;
+};
+
+/**
+ * done_already - determine if a reference has been done already.
+ * @done_tree: rb-tree to store references that have been done
+ * @lnum: LEB number of reference
+ *
+ * This function returns %1 if the reference has been done, %0 if not, otherwise
+ * a negative error code is returned.
+ */
+static int done_already(struct rb_root *done_tree, int lnum)
+{
+ struct rb_node **p = &done_tree->rb_node, *parent = NULL;
+ struct done_ref *dr;
+
+ while (*p) {
+ parent = *p;
+ dr = rb_entry(parent, struct done_ref, rb);
+ if (lnum < dr->lnum)
+ p = &(*p)->rb_left;
+ else if (lnum > dr->lnum)
+ p = &(*p)->rb_right;
+ else
+ return 1;
+ }
+
+ dr = kzalloc(sizeof(struct done_ref), GFP_NOFS);
+ if (!dr)
+ return -ENOMEM;
+
+ dr->lnum = lnum;
+
+ rb_link_node(&dr->rb, parent, p);
+ rb_insert_color(&dr->rb, done_tree);
+
+ return 0;
+}
+
+/**
+ * destroy_done_tree - destroy the done tree.
+ * @done_tree: done tree to destroy
+ */
+static void destroy_done_tree(struct rb_root *done_tree)
+{
+ struct rb_node *this = done_tree->rb_node;
+ struct done_ref *dr;
+
+ while (this) {
+ if (this->rb_left) {
+ this = this->rb_left;
+ continue;
+ } else if (this->rb_right) {
+ this = this->rb_right;
+ continue;
+ }
+ dr = rb_entry(this, struct done_ref, rb);
+ this = rb_parent(this);
+ if (this) {
+ if (this->rb_left == &dr->rb)
+ this->rb_left = NULL;
+ else
+ this->rb_right = NULL;
+ }
+ kfree(dr);
+ }
+}
+
+/**
+ * add_node - add a node to the consolidated log.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to which to add
+ * @lnum: LEB number to which to write is passed and returned here
+ * @offs: offset to where to write is passed and returned here
+ * @node: node to add
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int add_node(struct ubifs_info *c, void *buf, int *lnum, int *offs,
+ void *node)
+{
+ struct ubifs_ch *ch = node;
+ int len = le32_to_cpu(ch->len), remains = c->leb_size - *offs;
+
+ if (len > remains) {
+ int sz = ALIGN(*offs, c->min_io_size), err;
+
+ ubifs_pad(c, buf + *offs, sz - *offs);
+ err = ubifs_leb_change(c, *lnum, buf, sz, UBI_SHORTTERM);
+ if (err)
+ return err;
+ *lnum = next_log_lnum(c, *lnum);
+ *offs = 0;
+ }
+ memcpy(buf + *offs, node, len);
+ *offs += ALIGN(len, 8);
+ return 0;
+}
+
+/**
+ * ubifs_consolidate_log - consolidate the log.
+ * @c: UBIFS file-system description object
+ *
+ * Repeated failed commits could cause the log to be full, but at least 1 LEB is
+ * needed for commit. This function rewrites the reference nodes in the log
+ * omitting duplicates, and failed CS nodes, and leaving no gaps.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_consolidate_log(struct ubifs_info *c)
+{
+ struct ubifs_scan_leb *sleb;
+ struct ubifs_scan_node *snod;
+ struct rb_root done_tree = RB_ROOT;
+ int lnum, err, first = 1, write_lnum, offs = 0;
+ void *buf;
+
+ dbg_rcvry("log tail LEB %d, log head LEB %d", c->ltail_lnum,
+ c->lhead_lnum);
+ buf = vmalloc(c->leb_size);
+ if (!buf)
+ return -ENOMEM;
+ lnum = c->ltail_lnum;
+ write_lnum = lnum;
+ while (1) {
+ sleb = ubifs_scan(c, lnum, 0, c->sbuf);
+ if (IS_ERR(sleb)) {
+ err = PTR_ERR(sleb);
+ goto out_free;
+ }
+ list_for_each_entry(snod, &sleb->nodes, list) {
+ switch (snod->type) {
+ case UBIFS_REF_NODE: {
+ struct ubifs_ref_node *ref = snod->node;
+ int ref_lnum = le32_to_cpu(ref->lnum);
+
+ err = done_already(&done_tree, ref_lnum);
+ if (err < 0)
+ goto out_scan;
+ if (err != 1) {
+ err = add_node(c, buf, &write_lnum,
+ &offs, snod->node);
+ if (err)
+ goto out_scan;
+ }
+ break;
+ }
+ case UBIFS_CS_NODE:
+ if (!first)
+ break;
+ err = add_node(c, buf, &write_lnum, &offs,
+ snod->node);
+ if (err)
+ goto out_scan;
+ first = 0;
+ break;
+ }
+ }
+ ubifs_scan_destroy(sleb);
+ if (lnum == c->lhead_lnum)
+ break;
+ lnum = next_log_lnum(c, lnum);
+ }
+ if (offs) {
+ int sz = ALIGN(offs, c->min_io_size);
+
+ ubifs_pad(c, buf + offs, sz - offs);
+ err = ubifs_leb_change(c, write_lnum, buf, sz, UBI_SHORTTERM);
+ if (err)
+ goto out_free;
+ offs = ALIGN(offs, c->min_io_size);
+ }
+ destroy_done_tree(&done_tree);
+ vfree(buf);
+ if (write_lnum == c->lhead_lnum) {
+ ubifs_err("log is too full");
+ return -EINVAL;
+ }
+ /* Unmap remaining LEBs */
+ lnum = write_lnum;
+ do {
+ lnum = next_log_lnum(c, lnum);
+ err = ubifs_leb_unmap(c, lnum);
+ if (err)
+ return err;
+ } while (lnum != c->lhead_lnum);
+ c->lhead_lnum = write_lnum;
+ c->lhead_offs = offs;
+ dbg_rcvry("new log head at %d:%d", c->lhead_lnum, c->lhead_offs);
+ return 0;
+
+out_scan:
+ ubifs_scan_destroy(sleb);
+out_free:
+ destroy_done_tree(&done_tree);
+ vfree(buf);
+ return err;
+}
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+
+/**
+ * dbg_check_bud_bytes - make sure bud bytes calculation are all right.
+ * @c: UBIFS file-system description object
+ *
+ * This function makes sure the amount of flash space used by closed buds
+ * ('c->bud_bytes' is correct). Returns zero in case of success and %-EINVAL in
+ * case of failure.
+ */
+static int dbg_check_bud_bytes(struct ubifs_info *c)
+{
+ int i, err = 0;
+ struct ubifs_bud *bud;
+ long long bud_bytes = 0;
+
+ if (!(ubifs_chk_flags & UBIFS_CHK_GEN))
+ return 0;
+
+ spin_lock(&c->buds_lock);
+ for (i = 0; i < c->jhead_cnt; i++)
+ list_for_each_entry(bud, &c->jheads[i].buds_list, list)
+ bud_bytes += c->leb_size - bud->start;
+
+ if (c->bud_bytes != bud_bytes) {
+ ubifs_err("bad bud_bytes %lld, calculated %lld",
+ c->bud_bytes, bud_bytes);
+ err = -EINVAL;
+ }
+ spin_unlock(&c->buds_lock);
+
+ return err;
+}
+
+#endif /* CONFIG_UBIFS_FS_DEBUG */
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ * Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file implements the functions that access LEB properties and their
+ * categories. LEBs are categorized based on the needs of UBIFS, and the
+ * categories are stored as either heaps or lists to provide a fast way of
+ * finding a LEB in a particular category. For example, UBIFS may need to find
+ * an empty LEB for the journal, or a very dirty LEB for garbage collection.
+ */
+
+#include "ubifs.h"
+
+/**
+ * get_heap_comp_val - get the LEB properties value for heap comparisons.
+ * @lprops: LEB properties
+ * @cat: LEB category
+ */
+static int get_heap_comp_val(struct ubifs_lprops *lprops, int cat)
+{
+ switch (cat) {
+ case LPROPS_FREE:
+ return lprops->free;
+ case LPROPS_DIRTY_IDX:
+ return lprops->free + lprops->dirty;
+ default:
+ return lprops->dirty;
+ }
+}
+
+/**
+ * move_up_lpt_heap - move a new heap entry up as far as possible.
+ * @c: UBIFS file-system description object
+ * @heap: LEB category heap
+ * @lprops: LEB properties to move
+ * @cat: LEB category
+ *
+ * New entries to a heap are added at the bottom and then moved up until the
+ * parent's value is greater. In the case of LPT's category heaps, the value
+ * is either the amount of free space or the amount of dirty space, depending
+ * on the category.
+ */
+static void move_up_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
+ struct ubifs_lprops *lprops, int cat)
+{
+ int val1, val2, hpos;
+
+ hpos = lprops->hpos;
+ if (!hpos)
+ return; /* Already top of the heap */
+ val1 = get_heap_comp_val(lprops, cat);
+ /* Compare to parent and, if greater, move up the heap */
+ do {
+ int ppos = (hpos - 1) / 2;
+
+ val2 = get_heap_comp_val(heap->arr[ppos], cat);
+ if (val2 >= val1)
+ return;
+ /* Greater than parent so move up */
+ heap->arr[ppos]->hpos = hpos;
+ heap->arr[hpos] = heap->arr[ppos];
+ heap->arr[ppos] = lprops;
+ lprops->hpos = ppos;
+ hpos = ppos;
+ } while (hpos);
+}
+
+/**
+ * adjust_lpt_heap - move a changed heap entry up or down the heap.
+ * @c: UBIFS file-system description object
+ * @heap: LEB category heap
+ * @lprops: LEB properties to move
+ * @hpos: heap position of @lprops
+ * @cat: LEB category
+ *
+ * Changed entries in a heap are moved up or down until the parent's value is
+ * greater. In the case of LPT's category heaps, the value is either the amount
+ * of free space or the amount of dirty space, depending on the category.
+ */
+static void adjust_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
+ struct ubifs_lprops *lprops, int hpos, int cat)
+{
+ int val1, val2, val3, cpos;
+
+ val1 = get_heap_comp_val(lprops, cat);
+ /* Compare to parent and, if greater than parent, move up the heap */
+ if (hpos) {
+ int ppos = (hpos - 1) / 2;
+
+ val2 = get_heap_comp_val(heap->arr[ppos], cat);
+ if (val1 > val2) {
+ /* Greater than parent so move up */
+ while (1) {
+ heap->arr[ppos]->hpos = hpos;
+ heap->arr[hpos] = heap->arr[ppos];
+ heap->arr[ppos] = lprops;
+ lprops->hpos = ppos;
+ hpos = ppos;
+ if (!hpos)
+ return;
+ ppos = (hpos - 1) / 2;
+ val2 = get_heap_comp_val(heap->arr[ppos], cat);
+ if (val1 <= val2)
+ return;
+ /* Still greater than parent so keep going */
+ }
+ }
+ }
+ /* Not greater than parent, so compare to children */
+ while (1) {
+ /* Compare to left child */
+ cpos = hpos * 2 + 1;
+ if (cpos >= heap->cnt)
+ return;
+ val2 = get_heap_comp_val(heap->arr[cpos], cat);
+ if (val1 < val2) {
+ /* Less than left child, so promote biggest child */
+ if (cpos + 1 < heap->cnt) {
+ val3 = get_heap_comp_val(heap->arr[cpos + 1],
+ cat);
+ if (val3 > val2)
+ cpos += 1; /* Right child is bigger */
+ }
+ heap->arr[cpos]->hpos = hpos;
+ heap->arr[hpos] = heap->arr[cpos];
+ heap->arr[cpos] = lprops;
+ lprops->hpos = cpos;
+ hpos = cpos;
+ continue;
+ }
+ /* Compare to right child */
+ cpos += 1;
+ if (cpos >= heap->cnt)
+ return;
+ val3 = get_heap_comp_val(heap->arr[cpos], cat);
+ if (val1 < val3) {
+ /* Less than right child, so promote right child */
+ heap->arr[cpos]->hpos = hpos;
+ heap->arr[hpos] = heap->arr[cpos];
+ heap->arr[cpos] = lprops;
+ lprops->hpos = cpos;
+ hpos = cpos;
+ continue;
+ }
+ return;
+ }
+}
+
+/**
+ * add_to_lpt_heap - add LEB properties to a LEB category heap.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties to add
+ * @cat: LEB category
+ *
+ * This function returns %1 if @lprops is added to the heap for LEB category
+ * @cat, otherwise %0 is returned because the heap is full.
+ */
+static int add_to_lpt_heap(struct ubifs_info *c, struct ubifs_lprops *lprops,
+ int cat)
+{
+ struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
+
+ if (heap->cnt >= heap->max_cnt) {
+ const int b = LPT_HEAP_SZ / 2 - 1;
+ int cpos, val1, val2;
+
+ /* Compare to some other LEB on the bottom of heap */
+ /* Pick a position kind of randomly */
+ cpos = (((size_t)lprops >> 4) & b) + b;
+ ubifs_assert(cpos >= b);
+ ubifs_assert(cpos < LPT_HEAP_SZ);
+ ubifs_assert(cpos < heap->cnt);
+
+ val1 = get_heap_comp_val(lprops, cat);
+ val2 = get_heap_comp_val(heap->arr[cpos], cat);
+ if (val1 > val2) {
+ struct ubifs_lprops *lp;
+
+ lp = heap->arr[cpos];
+ lp->flags &= ~LPROPS_CAT_MASK;
+ lp->flags |= LPROPS_UNCAT;
+ list_add(&lp->list, &c->uncat_list);
+ lprops->hpos = cpos;
+ heap->arr[cpos] = lprops;
+ move_up_lpt_heap(c, heap, lprops, cat);
+ dbg_check_heap(c, heap, cat, lprops->hpos);
+ return 1; /* Added to heap */
+ }
+ dbg_check_heap(c, heap, cat, -1);
+ return 0; /* Not added to heap */
+ } else {
+ lprops->hpos = heap->cnt++;
+ heap->arr[lprops->hpos] = lprops;
+ move_up_lpt_heap(c, heap, lprops, cat);
+ dbg_check_heap(c, heap, cat, lprops->hpos);
+ return 1; /* Added to heap */
+ }
+}
+
+/**
+ * remove_from_lpt_heap - remove LEB properties from a LEB category heap.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties to remove
+ * @cat: LEB category
+ */
+static void remove_from_lpt_heap(struct ubifs_info *c,
+ struct ubifs_lprops *lprops, int cat)
+{
+ struct ubifs_lpt_heap *heap;
+ int hpos = lprops->hpos;
+
+ heap = &c->lpt_heap[cat - 1];
+ ubifs_assert(hpos >= 0 && hpos < heap->cnt);
+ ubifs_assert(heap->arr[hpos] == lprops);
+ heap->cnt -= 1;
+ if (hpos < heap->cnt) {
+ heap->arr[hpos] = heap->arr[heap->cnt];
+ heap->arr[hpos]->hpos = hpos;
+ adjust_lpt_heap(c, heap, heap->arr[hpos], hpos, cat);
+ }
+ dbg_check_heap(c, heap, cat, -1);
+}
+
+/**
+ * lpt_heap_replace - replace lprops in a category heap.
+ * @c: UBIFS file-system description object
+ * @old_lprops: LEB properties to replace
+ * @new_lprops: LEB properties with which to replace
+ * @cat: LEB category
+ *
+ * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode)
+ * and the lprops that the pnode contains. When that happens, references in
+ * the category heaps to those lprops must be updated to point to the new
+ * lprops. This function does that.
+ */
+static void lpt_heap_replace(struct ubifs_info *c,
+ struct ubifs_lprops *old_lprops,
+ struct ubifs_lprops *new_lprops, int cat)
+{
+ struct ubifs_lpt_heap *heap;
+ int hpos = new_lprops->hpos;
+
+ heap = &c->lpt_heap[cat - 1];
+ heap->arr[hpos] = new_lprops;
+}
+
+/**
+ * ubifs_add_to_cat - add LEB properties to a category list or heap.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties to add
+ * @cat: LEB category to which to add
+ *
+ * LEB properties are categorized to enable fast find operations.
+ */
+void ubifs_add_to_cat(struct ubifs_info *c, struct ubifs_lprops *lprops,
+ int cat)
+{
+ switch (cat) {
+ case LPROPS_DIRTY:
+ case LPROPS_DIRTY_IDX:
+ case LPROPS_FREE:
+ if (add_to_lpt_heap(c, lprops, cat))
+ break;
+ /* No more room on heap so make it uncategorized */
+ cat = LPROPS_UNCAT;
+ /* Fall through */
+ case LPROPS_UNCAT:
+ list_add(&lprops->list, &c->uncat_list);
+ break;
+ case LPROPS_EMPTY:
+ list_add(&lprops->list, &c->empty_list);
+ break;
+ case LPROPS_FREEABLE:
+ list_add(&lprops->list, &c->freeable_list);
+ c->freeable_cnt += 1;
+ break;
+ case LPROPS_FRDI_IDX:
+ list_add(&lprops->list, &c->frdi_idx_list);
+ break;
+ default:
+ ubifs_assert(0);
+ }
+ lprops->flags &= ~LPROPS_CAT_MASK;
+ lprops->flags |= cat;
+}
+
+/**
+ * ubifs_remove_from_cat - remove LEB properties from a category list or heap.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties to remove
+ * @cat: LEB category from which to remove
+ *
+ * LEB properties are categorized to enable fast find operations.
+ */
+static void ubifs_remove_from_cat(struct ubifs_info *c,
+ struct ubifs_lprops *lprops, int cat)
+{
+ switch (cat) {
+ case LPROPS_DIRTY:
+ case LPROPS_DIRTY_IDX:
+ case LPROPS_FREE:
+ remove_from_lpt_heap(c, lprops, cat);
+ break;
+ case LPROPS_FREEABLE:
+ c->freeable_cnt -= 1;
+ ubifs_assert(c->freeable_cnt >= 0);
+ /* Fall through */
+ case LPROPS_UNCAT:
+ case LPROPS_EMPTY:
+ case LPROPS_FRDI_IDX:
+ ubifs_assert(!list_empty(&lprops->list));
+ list_del(&lprops->list);
+ break;
+ default:
+ ubifs_assert(0);
+ }
+}
+
+/**
+ * ubifs_replace_cat - replace lprops in a category list or heap.
+ * @c: UBIFS file-system description object
+ * @old_lprops: LEB properties to replace
+ * @new_lprops: LEB properties with which to replace
+ *
+ * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode)
+ * and the lprops that the pnode contains. When that happens, references in
+ * category lists and heaps must be replaced. This function does that.
+ */
+void ubifs_replace_cat(struct ubifs_info *c, struct ubifs_lprops *old_lprops,
+ struct ubifs_lprops *new_lprops)
+{
+ int cat;
+
+ cat = new_lprops->flags & LPROPS_CAT_MASK;
+ switch (cat) {
+ case LPROPS_DIRTY:
+ case LPROPS_DIRTY_IDX:
+ case LPROPS_FREE:
+ lpt_heap_replace(c, old_lprops, new_lprops, cat);
+ break;
+ case LPROPS_UNCAT:
+ case LPROPS_EMPTY:
+ case LPROPS_FREEABLE:
+ case LPROPS_FRDI_IDX:
+ list_replace(&old_lprops->list, &new_lprops->list);
+ break;
+ default:
+ ubifs_assert(0);
+ }
+}
+
+/**
+ * ubifs_ensure_cat - ensure LEB properties are categorized.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties
+ *
+ * A LEB may have fallen off of the bottom of a heap, and ended up as
+ * uncategorized even though it has enough space for us now. If that is the case
+ * this function will put the LEB back onto a heap.
+ */
+void ubifs_ensure_cat(struct ubifs_info *c, struct ubifs_lprops *lprops)
+{
+ int cat = lprops->flags & LPROPS_CAT_MASK;
+
+ if (cat != LPROPS_UNCAT)
+ return;
+ cat = ubifs_categorize_lprops(c, lprops);
+ if (cat == LPROPS_UNCAT)
+ return;
+ ubifs_remove_from_cat(c, lprops, LPROPS_UNCAT);
+ ubifs_add_to_cat(c, lprops, cat);
+}
+
+/**
+ * ubifs_categorize_lprops - categorize LEB properties.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties to categorize
+ *
+ * LEB properties are categorized to enable fast find operations. This function
+ * returns the LEB category to which the LEB properties belong. Note however
+ * that if the LEB category is stored as a heap and the heap is full, the
+ * LEB properties may have their category changed to %LPROPS_UNCAT.
+ */
+int ubifs_categorize_lprops(const struct ubifs_info *c,
+ const struct ubifs_lprops *lprops)
+{
+ if (lprops->flags & LPROPS_TAKEN)
+ return LPROPS_UNCAT;
+
+ if (lprops->free == c->leb_size) {
+ ubifs_assert(!(lprops->flags & LPROPS_INDEX));
+ return LPROPS_EMPTY;
+ }
+
+ if (lprops->free + lprops->dirty == c->leb_size) {
+ if (lprops->flags & LPROPS_INDEX)
+ return LPROPS_FRDI_IDX;
+ else
+ return LPROPS_FREEABLE;
+ }
+
+ if (lprops->flags & LPROPS_INDEX) {
+ if (lprops->dirty + lprops->free >= c->min_idx_node_sz)
+ return LPROPS_DIRTY_IDX;
+ } else {
+ if (lprops->dirty >= c->dead_wm &&
+ lprops->dirty > lprops->free)
+ return LPROPS_DIRTY;
+ if (lprops->free > 0)
+ return LPROPS_FREE;
+ }
+
+ return LPROPS_UNCAT;
+}
+
+/**
+ * change_category - change LEB properties category.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties to recategorize
+ *
+ * LEB properties are categorized to enable fast find operations. When the LEB
+ * properties change they must be recategorized.
+ */
+static void change_category(struct ubifs_info *c, struct ubifs_lprops *lprops)
+{
+ int old_cat = lprops->flags & LPROPS_CAT_MASK;
+ int new_cat = ubifs_categorize_lprops(c, lprops);
+
+ if (old_cat == new_cat) {
+ struct ubifs_lpt_heap *heap = &c->lpt_heap[new_cat - 1];
+
+ /* lprops on a heap now must be moved up or down */
+ if (new_cat < 1 || new_cat > LPROPS_HEAP_CNT)
+ return; /* Not on a heap */
+ heap = &c->lpt_heap[new_cat - 1];
+ adjust_lpt_heap(c, heap, lprops, lprops->hpos, new_cat);
+ } else {
+ ubifs_remove_from_cat(c, lprops, old_cat);
+ ubifs_add_to_cat(c, lprops, new_cat);
+ }
+}
+
+/**
+ * ubifs_get_lprops - get reference to LEB properties.
+ * @c: the UBIFS file-system description object
+ *
+ * This function locks lprops. Lprops have to be unlocked by
+ * 'ubifs_release_lprops()'.
+ */
+void ubifs_get_lprops(struct ubifs_info *c)
+{
+ mutex_lock(&c->lp_mutex);
+}
+
+/**
+ * calc_dark - calculate LEB dark space size.
+ * @c: the UBIFS file-system description object
+ * @spc: amount of free and dirty space in the LEB
+ *
+ * This function calculates amount of dark space in an LEB which has @spc bytes
+ * of free and dirty space. Returns the calculations result.
+ *
+ * Dark space is the space which is not always usable - it depends on which
+ * nodes are written in which order. E.g., if an LEB has only 512 free bytes,
+ * it is dark space, because it cannot fit a large data node. So UBIFS cannot
+ * count on this LEB and treat these 512 bytes as usable because it is not true
+ * if, for example, only big chunks of uncompressible data will be written to
+ * the FS.
+ */
+static int calc_dark(struct ubifs_info *c, int spc)
+{
+ ubifs_assert(!(spc & 7));
+
+ if (spc < c->dark_wm)
+ return spc;
+
+ /*
+ * If we have slightly more space then the dark space watermark, we can
+ * anyway safely assume it we'll be able to write a node of the
+ * smallest size there.
+ */
+ if (spc - c->dark_wm < MIN_WRITE_SZ)
+ return spc - MIN_WRITE_SZ;
+
+ return c->dark_wm;
+}
+
+/**
+ * is_lprops_dirty - determine if LEB properties are dirty.
+ * @c: the UBIFS file-system description object
+ * @lprops: LEB properties to test
+ */
+static int is_lprops_dirty(struct ubifs_info *c, struct ubifs_lprops *lprops)
+{
+ struct ubifs_pnode *pnode;
+ int pos;
+
+ pos = (lprops->lnum - c->main_first) & (UBIFS_LPT_FANOUT - 1);
+ pnode = (struct ubifs_pnode *)container_of(lprops - pos,
+ struct ubifs_pnode,
+ lprops[0]);
+ return !test_bit(COW_ZNODE, &pnode->flags) &&
+ test_bit(DIRTY_CNODE, &pnode->flags);
+}
+
+/**
+ * ubifs_change_lp - change LEB properties.
+ * @c: the UBIFS file-system description object
+ * @lp: LEB properties to change
+ * @free: new free space amount
+ * @dirty: new dirty space amount
+ * @flags: new flags
+ * @idx_gc_cnt: change to the count of idx_gc list
+ *
+ * This function changes LEB properties. This function does not change a LEB
+ * property (@free, @dirty or @flag) if the value passed is %LPROPS_NC.
+ *
+ * This function returns a pointer to the updated LEB properties on success
+ * and a negative error code on failure. N.B. the LEB properties may have had to
+ * be copied (due to COW) and consequently the pointer returned may not be the
+ * same as the pointer passed.
+ */
+const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c,
+ const struct ubifs_lprops *lp,
+ int free, int dirty, int flags,
+ int idx_gc_cnt)
+{
+ /*
+ * This is the only function that is allowed to change lprops, so we
+ * discard the const qualifier.
+ */
+ struct ubifs_lprops *lprops = (struct ubifs_lprops *)lp;
+
+ dbg_lp("LEB %d, free %d, dirty %d, flags %d",
+ lprops->lnum, free, dirty, flags);
+
+ ubifs_assert(mutex_is_locked(&c->lp_mutex));
+ ubifs_assert(c->lst.empty_lebs >= 0 &&
+ c->lst.empty_lebs <= c->main_lebs);
+ ubifs_assert(c->freeable_cnt >= 0);
+ ubifs_assert(c->freeable_cnt <= c->main_lebs);
+ ubifs_assert(c->lst.taken_empty_lebs >= 0);
+ ubifs_assert(c->lst.taken_empty_lebs <= c->lst.empty_lebs);
+ ubifs_assert(!(c->lst.total_free & 7) && !(c->lst.total_dirty & 7));
+ ubifs_assert(!(c->lst.total_dead & 7) && !(c->lst.total_dark & 7));
+ ubifs_assert(!(c->lst.total_used & 7));
+ ubifs_assert(free == LPROPS_NC || free >= 0);
+ ubifs_assert(dirty == LPROPS_NC || dirty >= 0);
+
+ if (!is_lprops_dirty(c, lprops)) {
+ lprops = ubifs_lpt_lookup_dirty(c, lprops->lnum);
+ if (IS_ERR(lprops))
+ return lprops;
+ } else
+ ubifs_assert(lprops == ubifs_lpt_lookup_dirty(c, lprops->lnum));
+
+ ubifs_assert(!(lprops->free & 7) && !(lprops->dirty & 7));
+
+ spin_lock(&c->space_lock);
+
+ if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
+ c->lst.taken_empty_lebs -= 1;
+
+ if (!(lprops->flags & LPROPS_INDEX)) {
+ int old_spc;
+
+ old_spc = lprops->free + lprops->dirty;
+ if (old_spc < c->dead_wm)
+ c->lst.total_dead -= old_spc;
+ else
+ c->lst.total_dark -= calc_dark(c, old_spc);
+
+ c->lst.total_used -= c->leb_size - old_spc;
+ }
+
+ if (free != LPROPS_NC) {
+ free = ALIGN(free, 8);
+ c->lst.total_free += free - lprops->free;
+
+ /* Increase or decrease empty LEBs counter if needed */
+ if (free == c->leb_size) {
+ if (lprops->free != c->leb_size)
+ c->lst.empty_lebs += 1;
+ } else if (lprops->free == c->leb_size)
+ c->lst.empty_lebs -= 1;
+ lprops->free = free;
+ }
+
+ if (dirty != LPROPS_NC) {
+ dirty = ALIGN(dirty, 8);
+ c->lst.total_dirty += dirty - lprops->dirty;
+ lprops->dirty = dirty;
+ }
+
+ if (flags != LPROPS_NC) {
+ /* Take care about indexing LEBs counter if needed */
+ if ((lprops->flags & LPROPS_INDEX)) {
+ if (!(flags & LPROPS_INDEX))
+ c->lst.idx_lebs -= 1;
+ } else if (flags & LPROPS_INDEX)
+ c->lst.idx_lebs += 1;
+ lprops->flags = flags;
+ }
+
+ if (!(lprops->flags & LPROPS_INDEX)) {
+ int new_spc;
+
+ new_spc = lprops->free + lprops->dirty;
+ if (new_spc < c->dead_wm)
+ c->lst.total_dead += new_spc;
+ else
+ c->lst.total_dark += calc_dark(c, new_spc);
+
+ c->lst.total_used += c->leb_size - new_spc;
+ }
+
+ if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
+ c->lst.taken_empty_lebs += 1;
+
+ change_category(c, lprops);
+
+ c->idx_gc_cnt += idx_gc_cnt;
+
+ spin_unlock(&c->space_lock);
+
+ return lprops;
+}
+
+/**
+ * ubifs_release_lprops - release lprops lock.
+ * @c: the UBIFS file-system description object
+ *
+ * This function has to be called after each 'ubifs_get_lprops()' call to
+ * unlock lprops.
+ */
+void ubifs_release_lprops(struct ubifs_info *c)
+{
+ ubifs_assert(mutex_is_locked(&c->lp_mutex));
+ ubifs_assert(c->lst.empty_lebs >= 0 &&
+ c->lst.empty_lebs <= c->main_lebs);
+
+ mutex_unlock(&c->lp_mutex);
+}
+
+/**
+ * ubifs_get_lp_stats - get lprops statistics.
+ * @c: UBIFS file-system description object
+ * @st: return statistics
+ */
+void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *st)
+{
+ spin_lock(&c->space_lock);
+ memcpy(st, &c->lst, sizeof(struct ubifs_lp_stats));
+ spin_unlock(&c->space_lock);
+}
+
+/**
+ * ubifs_change_one_lp - change LEB properties.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB to change properties for
+ * @free: amount of free space
+ * @dirty: amount of dirty space
+ * @flags_set: flags to set
+ * @flags_clean: flags to clean
+ * @idx_gc_cnt: change to the count of idx_gc list
+ *
+ * This function changes properties of LEB @lnum. It is a helper wrapper over
+ * 'ubifs_change_lp()' which hides lprops get/release. The arguments are the
+ * same as in case of 'ubifs_change_lp()'. Returns zero in case of success and
+ * a negative error code in case of failure.
+ */
+int ubifs_change_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
+ int flags_set, int flags_clean, int idx_gc_cnt)
+{
+ int err = 0, flags;
+ const struct ubifs_lprops *lp;
+
+ ubifs_get_lprops(c);
+
+ lp = ubifs_lpt_lookup_dirty(c, lnum);
+ if (IS_ERR(lp)) {
+ err = PTR_ERR(lp);
+ goto out;
+ }
+
+ flags = (lp->flags | flags_set) & ~flags_clean;
+ lp = ubifs_change_lp(c, lp, free, dirty, flags, idx_gc_cnt);
+ if (IS_ERR(lp))
+ err = PTR_ERR(lp);
+
+out:
+ ubifs_release_lprops(c);
+ return err;
+}
+
+/**
+ * ubifs_update_one_lp - update LEB properties.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB to change properties for
+ * @free: amount of free space
+ * @dirty: amount of dirty space to add
+ * @flags_set: flags to set
+ * @flags_clean: flags to clean
+ *
+ * This function is the same as 'ubifs_change_one_lp()' but @dirty is added to
+ * current dirty space, not substitutes it.
+ */
+int ubifs_update_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
+ int flags_set, int flags_clean)
+{
+ int err = 0, flags;
+ const struct ubifs_lprops *lp;
+
+ ubifs_get_lprops(c);
+
+ lp = ubifs_lpt_lookup_dirty(c, lnum);
+ if (IS_ERR(lp)) {
+ err = PTR_ERR(lp);
+ goto out;
+ }
+
+ flags = (lp->flags | flags_set) & ~flags_clean;
+ lp = ubifs_change_lp(c, lp, free, lp->dirty + dirty, flags, 0);
+ if (IS_ERR(lp))
+ err = PTR_ERR(lp);
+
+out:
+ ubifs_release_lprops(c);
+ return err;
+}
+
+/**
+ * ubifs_read_one_lp - read LEB properties.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB to read properties for
+ * @lp: where to store read properties
+ *
+ * This helper function reads properties of a LEB @lnum and stores them in @lp.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+int ubifs_read_one_lp(struct ubifs_info *c, int lnum, struct ubifs_lprops *lp)
+{
+ int err = 0;
+ const struct ubifs_lprops *lpp;
+
+ ubifs_get_lprops(c);
+
+ lpp = ubifs_lpt_lookup(c, lnum);
+ if (IS_ERR(lpp)) {
+ err = PTR_ERR(lpp);
+ goto out;
+ }
+
+ memcpy(lp, lpp, sizeof(struct ubifs_lprops));
+
+out:
+ ubifs_release_lprops(c);
+ return err;
+}
+
+/**
+ * ubifs_fast_find_free - try to find a LEB with free space quickly.
+ * @c: the UBIFS file-system description object
+ *
+ * This function returns LEB properties for a LEB with free space or %NULL if
+ * the function is unable to find a LEB quickly.
+ */
+const struct ubifs_lprops *ubifs_fast_find_free(struct ubifs_info *c)
+{
+ struct ubifs_lprops *lprops;
+ struct ubifs_lpt_heap *heap;
+
+ ubifs_assert(mutex_is_locked(&c->lp_mutex));
+
+ heap = &c->lpt_heap[LPROPS_FREE - 1];
+ if (heap->cnt == 0)
+ return NULL;
+
+ lprops = heap->arr[0];
+ ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
+ ubifs_assert(!(lprops->flags & LPROPS_INDEX));
+ return lprops;
+}
+
+/**
+ * ubifs_fast_find_empty - try to find an empty LEB quickly.
+ * @c: the UBIFS file-system description object
+ *
+ * This function returns LEB properties for an empty LEB or %NULL if the
+ * function is unable to find an empty LEB quickly.
+ */
+const struct ubifs_lprops *ubifs_fast_find_empty(struct ubifs_info *c)
+{
+ struct ubifs_lprops *lprops;
+
+ ubifs_assert(mutex_is_locked(&c->lp_mutex));
+
+ if (list_empty(&c->empty_list))
+ return NULL;
+
+ lprops = list_entry(c->empty_list.next, struct ubifs_lprops, list);
+ ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
+ ubifs_assert(!(lprops->flags & LPROPS_INDEX));
+ ubifs_assert(lprops->free == c->leb_size);
+ return lprops;
+}
+
+/**
+ * ubifs_fast_find_freeable - try to find a freeable LEB quickly.
+ * @c: the UBIFS file-system description object
+ *
+ * This function returns LEB properties for a freeable LEB or %NULL if the
+ * function is unable to find a freeable LEB quickly.
+ */
+const struct ubifs_lprops *ubifs_fast_find_freeable(struct ubifs_info *c)
+{
+ struct ubifs_lprops *lprops;
+
+ ubifs_assert(mutex_is_locked(&c->lp_mutex));
+
+ if (list_empty(&c->freeable_list))
+ return NULL;
+
+ lprops = list_entry(c->freeable_list.next, struct ubifs_lprops, list);
+ ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
+ ubifs_assert(!(lprops->flags & LPROPS_INDEX));
+ ubifs_assert(lprops->free + lprops->dirty == c->leb_size);
+ ubifs_assert(c->freeable_cnt > 0);
+ return lprops;
+}
+
+/**
+ * ubifs_fast_find_frdi_idx - try to find a freeable index LEB quickly.
+ * @c: the UBIFS file-system description object
+ *
+ * This function returns LEB properties for a freeable index LEB or %NULL if the
+ * function is unable to find a freeable index LEB quickly.
+ */
+const struct ubifs_lprops *ubifs_fast_find_frdi_idx(struct ubifs_info *c)
+{
+ struct ubifs_lprops *lprops;
+
+ ubifs_assert(mutex_is_locked(&c->lp_mutex));
+
+ if (list_empty(&c->frdi_idx_list))
+ return NULL;
+
+ lprops = list_entry(c->frdi_idx_list.next, struct ubifs_lprops, list);
+ ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
+ ubifs_assert((lprops->flags & LPROPS_INDEX));
+ ubifs_assert(lprops->free + lprops->dirty == c->leb_size);
+ return lprops;
+}
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+
+/**
+ * dbg_check_cats - check category heaps and lists.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int dbg_check_cats(struct ubifs_info *c)
+{
+ struct ubifs_lprops *lprops;
+ struct list_head *pos;
+ int i, cat;
+
+ if (!(ubifs_chk_flags & (UBIFS_CHK_GEN | UBIFS_CHK_LPROPS)))
+ return 0;
+
+ list_for_each_entry(lprops, &c->empty_list, list) {
+ if (lprops->free != c->leb_size) {
+ ubifs_err("non-empty LEB %d on empty list "
+ "(free %d dirty %d flags %d)", lprops->lnum,
+ lprops->free, lprops->dirty, lprops->flags);
+ return -EINVAL;
+ }
+ if (lprops->flags & LPROPS_TAKEN) {
+ ubifs_err("taken LEB %d on empty list "
+ "(free %d dirty %d flags %d)", lprops->lnum,
+ lprops->free, lprops->dirty, lprops->flags);
+ return -EINVAL;
+ }
+ }
+
+ i = 0;
+ list_for_each_entry(lprops, &c->freeable_list, list) {
+ if (lprops->free + lprops->dirty != c->leb_size) {
+ ubifs_err("non-freeable LEB %d on freeable list "
+ "(free %d dirty %d flags %d)", lprops->lnum,
+ lprops->free, lprops->dirty, lprops->flags);
+ return -EINVAL;
+ }
+ if (lprops->flags & LPROPS_TAKEN) {
+ ubifs_err("taken LEB %d on freeable list "
+ "(free %d dirty %d flags %d)", lprops->lnum,
+ lprops->free, lprops->dirty, lprops->flags);
+ return -EINVAL;
+ }
+ i += 1;
+ }
+ if (i != c->freeable_cnt) {
+ ubifs_err("freeable list count %d expected %d", i,
+ c->freeable_cnt);
+ return -EINVAL;
+ }
+
+ i = 0;
+ list_for_each(pos, &c->idx_gc)
+ i += 1;
+ if (i != c->idx_gc_cnt) {
+ ubifs_err("idx_gc list count %d expected %d", i,
+ c->idx_gc_cnt);
+ return -EINVAL;
+ }
+
+ list_for_each_entry(lprops, &c->frdi_idx_list, list) {
+ if (lprops->free + lprops->dirty != c->leb_size) {
+ ubifs_err("non-freeable LEB %d on frdi_idx list "
+ "(free %d dirty %d flags %d)", lprops->lnum,
+ lprops->free, lprops->dirty, lprops->flags);
+ return -EINVAL;
+ }
+ if (lprops->flags & LPROPS_TAKEN) {
+ ubifs_err("taken LEB %d on frdi_idx list "
+ "(free %d dirty %d flags %d)", lprops->lnum,
+ lprops->free, lprops->dirty, lprops->flags);
+ return -EINVAL;
+ }
+ if (!(lprops->flags & LPROPS_INDEX)) {
+ ubifs_err("non-index LEB %d on frdi_idx list "
+ "(free %d dirty %d flags %d)", lprops->lnum,
+ lprops->free, lprops->dirty, lprops->flags);
+ return -EINVAL;
+ }
+ }
+
+ for (cat = 1; cat <= LPROPS_HEAP_CNT; cat++) {
+ struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
+
+ for (i = 0; i < heap->cnt; i++) {
+ lprops = heap->arr[i];
+ if (!lprops) {
+ ubifs_err("null ptr in LPT heap cat %d", cat);
+ return -EINVAL;
+ }
+ if (lprops->hpos != i) {
+ ubifs_err("bad ptr in LPT heap cat %d", cat);
+ return -EINVAL;
+ }
+ if (lprops->flags & LPROPS_TAKEN) {
+ ubifs_err("taken LEB in LPT heap cat %d", cat);
+ return -EINVAL;
+ }
+ }
+ }
+
+ return 0;
+}
+
+void dbg_check_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat,
+ int add_pos)
+{
+ int i = 0, j, err = 0;
+
+ if (!(ubifs_chk_flags & (UBIFS_CHK_GEN | UBIFS_CHK_LPROPS)))
+ return;
+
+ for (i = 0; i < heap->cnt; i++) {
+ struct ubifs_lprops *lprops = heap->arr[i];
+ struct ubifs_lprops *lp;
+
+ if (i != add_pos)
+ if ((lprops->flags & LPROPS_CAT_MASK) != cat) {
+ err = 1;
+ goto out;
+ }
+ if (lprops->hpos != i) {
+ err = 2;
+ goto out;
+ }
+ lp = ubifs_lpt_lookup(c, lprops->lnum);
+ if (IS_ERR(lp)) {
+ err = 3;
+ goto out;
+ }
+ if (lprops != lp) {
+ dbg_msg("lprops %zx lp %zx lprops->lnum %d lp->lnum %d",
+ (size_t)lprops, (size_t)lp, lprops->lnum,
+ lp->lnum);
+ err = 4;
+ goto out;
+ }
+ for (j = 0; j < i; j++) {
+ lp = heap->arr[j];
+ if (lp == lprops) {
+ err = 5;
+ goto out;
+ }
+ if (lp->lnum == lprops->lnum) {
+ err = 6;
+ goto out;
+ }
+ }
+ }
+out:
+ if (err) {
+ dbg_msg("failed cat %d hpos %d err %d", cat, i, err);
+ dbg_dump_stack();
+ dbg_dump_heap(c, heap, cat);
+ }
+}
+
+/**
+ * struct scan_check_data - data provided to scan callback function.
+ * @lst: LEB properties statistics
+ * @err: error code
+ */
+struct scan_check_data {
+ struct ubifs_lp_stats lst;
+ int err;
+};
+
+/**
+ * scan_check_cb - scan callback.
+ * @c: the UBIFS file-system description object
+ * @lp: LEB properties to scan
+ * @in_tree: whether the LEB properties are in main memory
+ * @data: information passed to and from the caller of the scan
+ *
+ * This function returns a code that indicates whether the scan should continue
+ * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree
+ * in main memory (%LPT_SCAN_ADD), or whether the scan should stop
+ * (%LPT_SCAN_STOP).
+ */
+static int scan_check_cb(struct ubifs_info *c,
+ const struct ubifs_lprops *lp, int in_tree,
+ struct scan_check_data *data)
+{
+ struct ubifs_scan_leb *sleb;
+ struct ubifs_scan_node *snod;
+ struct ubifs_lp_stats *lst = &data->lst;
+ int cat, lnum = lp->lnum, is_idx = 0, used = 0, free, dirty;
+
+ cat = lp->flags & LPROPS_CAT_MASK;
+ if (cat != LPROPS_UNCAT) {
+ cat = ubifs_categorize_lprops(c, lp);
+ if (cat != (lp->flags & LPROPS_CAT_MASK)) {
+ ubifs_err("bad LEB category %d expected %d",
+ (lp->flags & LPROPS_CAT_MASK), cat);
+ goto out;
+ }
+ }
+
+ /* Check lp is on its category list (if it has one) */
+ if (in_tree) {
+ struct list_head *list = NULL;
+
+ switch (cat) {
+ case LPROPS_EMPTY:
+ list = &c->empty_list;
+ break;
+ case LPROPS_FREEABLE:
+ list = &c->freeable_list;
+ break;
+ case LPROPS_FRDI_IDX:
+ list = &c->frdi_idx_list;
+ break;
+ case LPROPS_UNCAT:
+ list = &c->uncat_list;
+ break;
+ }
+ if (list) {
+ struct ubifs_lprops *lprops;
+ int found = 0;
+
+ list_for_each_entry(lprops, list, list) {
+ if (lprops == lp) {
+ found = 1;
+ break;
+ }
+ }
+ if (!found) {
+ ubifs_err("bad LPT list (category %d)", cat);
+ goto out;
+ }
+ }
+ }
+
+ /* Check lp is on its category heap (if it has one) */
+ if (in_tree && cat > 0 && cat <= LPROPS_HEAP_CNT) {
+ struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
+
+ if ((lp->hpos != -1 && heap->arr[lp->hpos]->lnum != lnum) ||
+ lp != heap->arr[lp->hpos]) {
+ ubifs_err("bad LPT heap (category %d)", cat);
+ goto out;
+ }
+ }
+
+ sleb = ubifs_scan(c, lnum, 0, c->dbg_buf);
+ if (IS_ERR(sleb)) {
+ /*
+ * After an unclean unmount, empty and freeable LEBs
+ * may contain garbage.
+ */
+ if (lp->free == c->leb_size) {
+ ubifs_err("scan errors were in empty LEB "
+ "- continuing checking");
+ lst->empty_lebs += 1;
+ lst->total_free += c->leb_size;
+ lst->total_dark += calc_dark(c, c->leb_size);
+ return LPT_SCAN_CONTINUE;
+ }
+
+ if (lp->free + lp->dirty == c->leb_size &&
+ !(lp->flags & LPROPS_INDEX)) {
+ ubifs_err("scan errors were in freeable LEB "
+ "- continuing checking");
+ lst->total_free += lp->free;
+ lst->total_dirty += lp->dirty;
+ lst->total_dark += calc_dark(c, c->leb_size);
+ return LPT_SCAN_CONTINUE;
+ }
+ data->err = PTR_ERR(sleb);
+ return LPT_SCAN_STOP;
+ }
+
+ is_idx = -1;
+ list_for_each_entry(snod, &sleb->nodes, list) {
+ int found, level = 0;
+
+ cond_resched();
+
+ if (is_idx == -1)
+ is_idx = (snod->type == UBIFS_IDX_NODE) ? 1 : 0;
+
+ if (is_idx && snod->type != UBIFS_IDX_NODE) {
+ ubifs_err("indexing node in data LEB %d:%d",
+ lnum, snod->offs);
+ goto out_destroy;
+ }
+
+ if (snod->type == UBIFS_IDX_NODE) {
+ struct ubifs_idx_node *idx = snod->node;
+
+ key_read(c, ubifs_idx_key(c, idx), &snod->key);
+ level = le16_to_cpu(idx->level);
+ }
+
+ found = ubifs_tnc_has_node(c, &snod->key, level, lnum,
+ snod->offs, is_idx);
+ if (found) {
+ if (found < 0)
+ goto out_destroy;
+ used += ALIGN(snod->len, 8);
+ }
+ }
+
+ free = c->leb_size - sleb->endpt;
+ dirty = sleb->endpt - used;
+
+ if (free > c->leb_size || free < 0 || dirty > c->leb_size ||
+ dirty < 0) {
+ ubifs_err("bad calculated accounting for LEB %d: "
+ "free %d, dirty %d", lnum, free, dirty);
+ goto out_destroy;
+ }
+
+ if (lp->free + lp->dirty == c->leb_size &&
+ free + dirty == c->leb_size)
+ if ((is_idx && !(lp->flags & LPROPS_INDEX)) ||
+ (!is_idx && free == c->leb_size) ||
+ lp->free == c->leb_size) {
+ /*
+ * Empty or freeable LEBs could contain index
+ * nodes from an uncompleted commit due to an
+ * unclean unmount. Or they could be empty for
+ * the same reason. Or it may simply not have been
+ * unmapped.
+ */
+ free = lp->free;
+ dirty = lp->dirty;
+ is_idx = 0;
+ }
+
+ if (is_idx && lp->free + lp->dirty == free + dirty &&
+ lnum != c->ihead_lnum) {
+ /*
+ * After an unclean unmount, an index LEB could have a different
+ * amount of free space than the value recorded by lprops. That
+ * is because the in-the-gaps method may use free space or
+ * create free space (as a side-effect of using ubi_leb_change
+ * and not writing the whole LEB). The incorrect free space
+ * value is not a problem because the index is only ever
+ * allocated empty LEBs, so there will never be an attempt to
+ * write to the free space at the end of an index LEB - except
+ * by the in-the-gaps method for which it is not a problem.
+ */
+ free = lp->free;
+ dirty = lp->dirty;
+ }
+
+ if (lp->free != free || lp->dirty != dirty)
+ goto out_print;
+
+ if (is_idx && !(lp->flags & LPROPS_INDEX)) {
+ if (free == c->leb_size)
+ /* Free but not unmapped LEB, it's fine */
+ is_idx = 0;
+ else {
+ ubifs_err("indexing node without indexing "
+ "flag");
+ goto out_print;
+ }
+ }
+
+ if (!is_idx && (lp->flags & LPROPS_INDEX)) {
+ ubifs_err("data node with indexing flag");
+ goto out_print;
+ }
+
+ if (free == c->leb_size)
+ lst->empty_lebs += 1;
+
+ if (is_idx)
+ lst->idx_lebs += 1;
+
+ if (!(lp->flags & LPROPS_INDEX))
+ lst->total_used += c->leb_size - free - dirty;
+ lst->total_free += free;
+ lst->total_dirty += dirty;
+
+ if (!(lp->flags & LPROPS_INDEX)) {
+ int spc = free + dirty;
+
+ if (spc < c->dead_wm)
+ lst->total_dead += spc;
+ else
+ lst->total_dark += calc_dark(c, spc);
+ }
+
+ ubifs_scan_destroy(sleb);
+
+ return LPT_SCAN_CONTINUE;
+
+out_print:
+ ubifs_err("bad accounting of LEB %d: free %d, dirty %d flags %#x, "
+ "should be free %d, dirty %d",
+ lnum, lp->free, lp->dirty, lp->flags, free, dirty);
+ dbg_dump_leb(c, lnum);
+out_destroy:
+ ubifs_scan_destroy(sleb);
+out:
+ data->err = -EINVAL;
+ return LPT_SCAN_STOP;
+}
+
+/**
+ * dbg_check_lprops - check all LEB properties.
+ * @c: UBIFS file-system description object
+ *
+ * This function checks all LEB properties and makes sure they are all correct.
+ * It returns zero if everything is fine, %-EINVAL if there is an inconsistency
+ * and other negative error codes in case of other errors. This function is
+ * called while the file system is locked (because of commit start), so no
+ * additional locking is required. Note that locking the LPT mutex would cause
+ * a circular lock dependency with the TNC mutex.
+ */
+int dbg_check_lprops(struct ubifs_info *c)
+{
+ int i, err;
+ struct scan_check_data data;
+ struct ubifs_lp_stats *lst = &data.lst;
+
+ if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS))
+ return 0;
+
+ /*
+ * As we are going to scan the media, the write buffers have to be
+ * synchronized.
+ */
+ for (i = 0; i < c->jhead_cnt; i++) {
+ err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
+ if (err)
+ return err;
+ }
+
+ memset(lst, 0, sizeof(struct ubifs_lp_stats));
+
+ data.err = 0;
+ err = ubifs_lpt_scan_nolock(c, c->main_first, c->leb_cnt - 1,
+ (ubifs_lpt_scan_callback)scan_check_cb,
+ &data);
+ if (err && err != -ENOSPC)
+ goto out;
+ if (data.err) {
+ err = data.err;
+ goto out;
+ }
+
+ if (lst->empty_lebs != c->lst.empty_lebs ||
+ lst->idx_lebs != c->lst.idx_lebs ||
+ lst->total_free != c->lst.total_free ||
+ lst->total_dirty != c->lst.total_dirty ||
+ lst->total_used != c->lst.total_used) {
+ ubifs_err("bad overall accounting");
+ ubifs_err("calculated: empty_lebs %d, idx_lebs %d, "
+ "total_free %lld, total_dirty %lld, total_used %lld",
+ lst->empty_lebs, lst->idx_lebs, lst->total_free,
+ lst->total_dirty, lst->total_used);
+ ubifs_err("read from lprops: empty_lebs %d, idx_lebs %d, "
+ "total_free %lld, total_dirty %lld, total_used %lld",
+ c->lst.empty_lebs, c->lst.idx_lebs, c->lst.total_free,
+ c->lst.total_dirty, c->lst.total_used);
+ err = -EINVAL;
+ goto out;
+ }
+
+ if (lst->total_dead != c->lst.total_dead ||
+ lst->total_dark != c->lst.total_dark) {
+ ubifs_err("bad dead/dark space accounting");
+ ubifs_err("calculated: total_dead %lld, total_dark %lld",
+ lst->total_dead, lst->total_dark);
+ ubifs_err("read from lprops: total_dead %lld, total_dark %lld",
+ c->lst.total_dead, c->lst.total_dark);
+ err = -EINVAL;
+ goto out;
+ }
+
+ err = dbg_check_cats(c);
+out:
+ return err;
+}
+
+#endif /* CONFIG_UBIFS_FS_DEBUG */
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ * Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file implements the LEB properties tree (LPT) area. The LPT area
+ * contains the LEB properties tree, a table of LPT area eraseblocks (ltab), and
+ * (for the "big" model) a table of saved LEB numbers (lsave). The LPT area sits
+ * between the log and the orphan area.
+ *
+ * The LPT area is like a miniature self-contained file system. It is required
+ * that it never runs out of space, is fast to access and update, and scales
+ * logarithmically. The LEB properties tree is implemented as a wandering tree
+ * much like the TNC, and the LPT area has its own garbage collection.
+ *
+ * The LPT has two slightly different forms called the "small model" and the
+ * "big model". The small model is used when the entire LEB properties table
+ * can be written into a single eraseblock. In that case, garbage collection
+ * consists of just writing the whole table, which therefore makes all other
+ * eraseblocks reusable. In the case of the big model, dirty eraseblocks are
+ * selected for garbage collection, which consists are marking the nodes in
+ * that LEB as dirty, and then only the dirty nodes are written out. Also, in
+ * the case of the big model, a table of LEB numbers is saved so that the entire
+ * LPT does not to be scanned looking for empty eraseblocks when UBIFS is first
+ * mounted.
+ */
+
+#include <linux/crc16.h>
+#include "ubifs.h"
+
+/**
+ * do_calc_lpt_geom - calculate sizes for the LPT area.
+ * @c: the UBIFS file-system description object
+ *
+ * Calculate the sizes of LPT bit fields, nodes, and tree, based on the
+ * properties of the flash and whether LPT is "big" (c->big_lpt).
+ */
+static void do_calc_lpt_geom(struct ubifs_info *c)
+{
+ int i, n, bits, per_leb_wastage, max_pnode_cnt;
+ long long sz, tot_wastage;
+
+ n = c->main_lebs + c->max_leb_cnt - c->leb_cnt;
+ max_pnode_cnt = DIV_ROUND_UP(n, UBIFS_LPT_FANOUT);
+
+ c->lpt_hght = 1;
+ n = UBIFS_LPT_FANOUT;
+ while (n < max_pnode_cnt) {
+ c->lpt_hght += 1;
+ n <<= UBIFS_LPT_FANOUT_SHIFT;
+ }
+
+ c->pnode_cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT);
+
+ n = DIV_ROUND_UP(c->pnode_cnt, UBIFS_LPT_FANOUT);
+ c->nnode_cnt = n;
+ for (i = 1; i < c->lpt_hght; i++) {
+ n = DIV_ROUND_UP(n, UBIFS_LPT_FANOUT);
+ c->nnode_cnt += n;
+ }
+
+ c->space_bits = fls(c->leb_size) - 3;
+ c->lpt_lnum_bits = fls(c->lpt_lebs);
+ c->lpt_offs_bits = fls(c->leb_size - 1);
+ c->lpt_spc_bits = fls(c->leb_size);
+
+ n = DIV_ROUND_UP(c->max_leb_cnt, UBIFS_LPT_FANOUT);
+ c->pcnt_bits = fls(n - 1);
+
+ c->lnum_bits = fls(c->max_leb_cnt - 1);
+
+ bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
+ (c->big_lpt ? c->pcnt_bits : 0) +
+ (c->space_bits * 2 + 1) * UBIFS_LPT_FANOUT;
+ c->pnode_sz = (bits + 7) / 8;
+
+ bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
+ (c->big_lpt ? c->pcnt_bits : 0) +
+ (c->lpt_lnum_bits + c->lpt_offs_bits) * UBIFS_LPT_FANOUT;
+ c->nnode_sz = (bits + 7) / 8;
+
+ bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
+ c->lpt_lebs * c->lpt_spc_bits * 2;
+ c->ltab_sz = (bits + 7) / 8;
+
+ bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
+ c->lnum_bits * c->lsave_cnt;
+ c->lsave_sz = (bits + 7) / 8;
+
+ /* Calculate the minimum LPT size */
+ c->lpt_sz = (long long)c->pnode_cnt * c->pnode_sz;
+ c->lpt_sz += (long long)c->nnode_cnt * c->nnode_sz;
+ c->lpt_sz += c->ltab_sz;
+ c->lpt_sz += c->lsave_sz;
+
+ /* Add wastage */
+ sz = c->lpt_sz;
+ per_leb_wastage = max_t(int, c->pnode_sz, c->nnode_sz);
+ sz += per_leb_wastage;
+ tot_wastage = per_leb_wastage;
+ while (sz > c->leb_size) {
+ sz += per_leb_wastage;
+ sz -= c->leb_size;
+ tot_wastage += per_leb_wastage;
+ }
+ tot_wastage += ALIGN(sz, c->min_io_size) - sz;
+ c->lpt_sz += tot_wastage;
+}
+
+/**
+ * ubifs_calc_lpt_geom - calculate and check sizes for the LPT area.
+ * @c: the UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_calc_lpt_geom(struct ubifs_info *c)
+{
+ int lebs_needed;
+ uint64_t sz;
+
+ do_calc_lpt_geom(c);
+
+ /* Verify that lpt_lebs is big enough */
+ sz = c->lpt_sz * 2; /* Must have at least 2 times the size */
+ sz += c->leb_size - 1;
+ do_div(sz, c->leb_size);
+ lebs_needed = sz;
+ if (lebs_needed > c->lpt_lebs) {
+ ubifs_err("too few LPT LEBs");
+ return -EINVAL;
+ }
+
+ /* Verify that ltab fits in a single LEB (since ltab is a single node */
+ if (c->ltab_sz > c->leb_size) {
+ ubifs_err("LPT ltab too big");
+ return -EINVAL;
+ }
+
+ c->check_lpt_free = c->big_lpt;
+
+ return 0;
+}
+
+/**
+ * calc_dflt_lpt_geom - calculate default LPT geometry.
+ * @c: the UBIFS file-system description object
+ * @main_lebs: number of main area LEBs is passed and returned here
+ * @big_lpt: whether the LPT area is "big" is returned here
+ *
+ * The size of the LPT area depends on parameters that themselves are dependent
+ * on the size of the LPT area. This function, successively recalculates the LPT
+ * area geometry until the parameters and resultant geometry are consistent.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int calc_dflt_lpt_geom(struct ubifs_info *c, int *main_lebs,
+ int *big_lpt)
+{
+ int i, lebs_needed;
+ uint64_t sz;
+
+ /* Start by assuming the minimum number of LPT LEBs */
+ c->lpt_lebs = UBIFS_MIN_LPT_LEBS;
+ c->main_lebs = *main_lebs - c->lpt_lebs;
+ if (c->main_lebs <= 0)
+ return -EINVAL;
+
+ /* And assume we will use the small LPT model */
+ c->big_lpt = 0;
+
+ /*
+ * Calculate the geometry based on assumptions above and then see if it
+ * makes sense
+ */
+ do_calc_lpt_geom(c);
+
+ /* Small LPT model must have lpt_sz < leb_size */
+ if (c->lpt_sz > c->leb_size) {
+ /* Nope, so try again using big LPT model */
+ c->big_lpt = 1;
+ do_calc_lpt_geom(c);
+ }
+
+ /* Now check there are enough LPT LEBs */
+ for (i = 0; i < 64 ; i++) {
+ sz = c->lpt_sz * 4; /* Allow 4 times the size */
+ sz += c->leb_size - 1;
+ do_div(sz, c->leb_size);
+ lebs_needed = sz;
+ if (lebs_needed > c->lpt_lebs) {
+ /* Not enough LPT LEBs so try again with more */
+ c->lpt_lebs = lebs_needed;
+ c->main_lebs = *main_lebs - c->lpt_lebs;
+ if (c->main_lebs <= 0)
+ return -EINVAL;
+ do_calc_lpt_geom(c);
+ continue;
+ }
+ if (c->ltab_sz > c->leb_size) {
+ ubifs_err("LPT ltab too big");
+ return -EINVAL;
+ }
+ *main_lebs = c->main_lebs;
+ *big_lpt = c->big_lpt;
+ return 0;
+ }
+ return -EINVAL;
+}
+
+/**
+ * pack_bits - pack bit fields end-to-end.
+ * @addr: address at which to pack (passed and next address returned)
+ * @pos: bit position at which to pack (passed and next position returned)
+ * @val: value to pack
+ * @nrbits: number of bits of value to pack (1-32)
+ */
+static void pack_bits(uint8_t **addr, int *pos, uint32_t val, int nrbits)
+{
+ uint8_t *p = *addr;
+ int b = *pos;
+
+ ubifs_assert(nrbits > 0);
+ ubifs_assert(nrbits <= 32);
+ ubifs_assert(*pos >= 0);
+ ubifs_assert(*pos < 8);
+ ubifs_assert((val >> nrbits) == 0 || nrbits == 32);
+ if (b) {
+ *p |= ((uint8_t)val) << b;
+ nrbits += b;
+ if (nrbits > 8) {
+ *++p = (uint8_t)(val >>= (8 - b));
+ if (nrbits > 16) {
+ *++p = (uint8_t)(val >>= 8);
+ if (nrbits > 24) {
+ *++p = (uint8_t)(val >>= 8);
+ if (nrbits > 32)
+ *++p = (uint8_t)(val >>= 8);
+ }
+ }
+ }
+ } else {
+ *p = (uint8_t)val;
+ if (nrbits > 8) {
+ *++p = (uint8_t)(val >>= 8);
+ if (nrbits > 16) {
+ *++p = (uint8_t)(val >>= 8);
+ if (nrbits > 24)
+ *++p = (uint8_t)(val >>= 8);
+ }
+ }
+ }
+ b = nrbits & 7;
+ if (b == 0)
+ p++;
+ *addr = p;
+ *pos = b;
+}
+
+/**
+ * ubifs_unpack_bits - unpack bit fields.
+ * @addr: address at which to unpack (passed and next address returned)
+ * @pos: bit position at which to unpack (passed and next position returned)
+ * @nrbits: number of bits of value to unpack (1-32)
+ *
+ * This functions returns the value unpacked.
+ */
+uint32_t ubifs_unpack_bits(uint8_t **addr, int *pos, int nrbits)
+{
+ const int k = 32 - nrbits;
+ uint8_t *p = *addr;
+ int b = *pos;
+ uint32_t val;
+
+ ubifs_assert(nrbits > 0);
+ ubifs_assert(nrbits <= 32);
+ ubifs_assert(*pos >= 0);
+ ubifs_assert(*pos < 8);
+ if (b) {
+ val = p[1] | ((uint32_t)p[2] << 8) | ((uint32_t)p[3] << 16) |
+ ((uint32_t)p[4] << 24);
+ val <<= (8 - b);
+ val |= *p >> b;
+ nrbits += b;
+ } else
+ val = p[0] | ((uint32_t)p[1] << 8) | ((uint32_t)p[2] << 16) |
+ ((uint32_t)p[3] << 24);
+ val <<= k;
+ val >>= k;
+ b = nrbits & 7;
+ p += nrbits / 8;
+ *addr = p;
+ *pos = b;
+ ubifs_assert((val >> nrbits) == 0 || nrbits - b == 32);
+ return val;
+}
+
+/**
+ * ubifs_pack_pnode - pack all the bit fields of a pnode.
+ * @c: UBIFS file-system description object
+ * @buf: buffer into which to pack
+ * @pnode: pnode to pack
+ */
+void ubifs_pack_pnode(struct ubifs_info *c, void *buf,
+ struct ubifs_pnode *pnode)
+{
+ uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+ int i, pos = 0;
+ uint16_t crc;
+
+ pack_bits(&addr, &pos, UBIFS_LPT_PNODE, UBIFS_LPT_TYPE_BITS);
+ if (c->big_lpt)
+ pack_bits(&addr, &pos, pnode->num, c->pcnt_bits);
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ pack_bits(&addr, &pos, pnode->lprops[i].free >> 3,
+ c->space_bits);
+ pack_bits(&addr, &pos, pnode->lprops[i].dirty >> 3,
+ c->space_bits);
+ if (pnode->lprops[i].flags & LPROPS_INDEX)
+ pack_bits(&addr, &pos, 1, 1);
+ else
+ pack_bits(&addr, &pos, 0, 1);
+ }
+ crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
+ c->pnode_sz - UBIFS_LPT_CRC_BYTES);
+ addr = buf;
+ pos = 0;
+ pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
+}
+
+/**
+ * ubifs_pack_nnode - pack all the bit fields of a nnode.
+ * @c: UBIFS file-system description object
+ * @buf: buffer into which to pack
+ * @nnode: nnode to pack
+ */
+void ubifs_pack_nnode(struct ubifs_info *c, void *buf,
+ struct ubifs_nnode *nnode)
+{
+ uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+ int i, pos = 0;
+ uint16_t crc;
+
+ pack_bits(&addr, &pos, UBIFS_LPT_NNODE, UBIFS_LPT_TYPE_BITS);
+ if (c->big_lpt)
+ pack_bits(&addr, &pos, nnode->num, c->pcnt_bits);
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ int lnum = nnode->nbranch[i].lnum;
+
+ if (lnum == 0)
+ lnum = c->lpt_last + 1;
+ pack_bits(&addr, &pos, lnum - c->lpt_first, c->lpt_lnum_bits);
+ pack_bits(&addr, &pos, nnode->nbranch[i].offs,
+ c->lpt_offs_bits);
+ }
+ crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
+ c->nnode_sz - UBIFS_LPT_CRC_BYTES);
+ addr = buf;
+ pos = 0;
+ pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
+}
+
+/**
+ * ubifs_pack_ltab - pack the LPT's own lprops table.
+ * @c: UBIFS file-system description object
+ * @buf: buffer into which to pack
+ * @ltab: LPT's own lprops table to pack
+ */
+void ubifs_pack_ltab(struct ubifs_info *c, void *buf,
+ struct ubifs_lpt_lprops *ltab)
+{
+ uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+ int i, pos = 0;
+ uint16_t crc;
+
+ pack_bits(&addr, &pos, UBIFS_LPT_LTAB, UBIFS_LPT_TYPE_BITS);
+ for (i = 0; i < c->lpt_lebs; i++) {
+ pack_bits(&addr, &pos, ltab[i].free, c->lpt_spc_bits);
+ pack_bits(&addr, &pos, ltab[i].dirty, c->lpt_spc_bits);
+ }
+ crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
+ c->ltab_sz - UBIFS_LPT_CRC_BYTES);
+ addr = buf;
+ pos = 0;
+ pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
+}
+
+/**
+ * ubifs_pack_lsave - pack the LPT's save table.
+ * @c: UBIFS file-system description object
+ * @buf: buffer into which to pack
+ * @lsave: LPT's save table to pack
+ */
+void ubifs_pack_lsave(struct ubifs_info *c, void *buf, int *lsave)
+{
+ uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+ int i, pos = 0;
+ uint16_t crc;
+
+ pack_bits(&addr, &pos, UBIFS_LPT_LSAVE, UBIFS_LPT_TYPE_BITS);
+ for (i = 0; i < c->lsave_cnt; i++)
+ pack_bits(&addr, &pos, lsave[i], c->lnum_bits);
+ crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
+ c->lsave_sz - UBIFS_LPT_CRC_BYTES);
+ addr = buf;
+ pos = 0;
+ pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
+}
+
+/**
+ * ubifs_add_lpt_dirt - add dirty space to LPT LEB properties.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to which to add dirty space
+ * @dirty: amount of dirty space to add
+ */
+void ubifs_add_lpt_dirt(struct ubifs_info *c, int lnum, int dirty)
+{
+ if (!dirty || !lnum)
+ return;
+ dbg_lp("LEB %d add %d to %d",
+ lnum, dirty, c->ltab[lnum - c->lpt_first].dirty);
+ ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last);
+ c->ltab[lnum - c->lpt_first].dirty += dirty;
+}
+
+/**
+ * set_ltab - set LPT LEB properties.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number
+ * @free: amount of free space
+ * @dirty: amount of dirty space
+ */
+static void set_ltab(struct ubifs_info *c, int lnum, int free, int dirty)
+{
+ dbg_lp("LEB %d free %d dirty %d to %d %d",
+ lnum, c->ltab[lnum - c->lpt_first].free,
+ c->ltab[lnum - c->lpt_first].dirty, free, dirty);
+ ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last);
+ c->ltab[lnum - c->lpt_first].free = free;
+ c->ltab[lnum - c->lpt_first].dirty = dirty;
+}
+
+/**
+ * ubifs_add_nnode_dirt - add dirty space to LPT LEB properties.
+ * @c: UBIFS file-system description object
+ * @nnode: nnode for which to add dirt
+ */
+void ubifs_add_nnode_dirt(struct ubifs_info *c, struct ubifs_nnode *nnode)
+{
+ struct ubifs_nnode *np = nnode->parent;
+
+ if (np)
+ ubifs_add_lpt_dirt(c, np->nbranch[nnode->iip].lnum,
+ c->nnode_sz);
+ else {
+ ubifs_add_lpt_dirt(c, c->lpt_lnum, c->nnode_sz);
+ if (!(c->lpt_drty_flgs & LTAB_DIRTY)) {
+ c->lpt_drty_flgs |= LTAB_DIRTY;
+ ubifs_add_lpt_dirt(c, c->ltab_lnum, c->ltab_sz);
+ }
+ }
+}
+
+/**
+ * add_pnode_dirt - add dirty space to LPT LEB properties.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode for which to add dirt
+ */
+static void add_pnode_dirt(struct ubifs_info *c, struct ubifs_pnode *pnode)
+{
+ ubifs_add_lpt_dirt(c, pnode->parent->nbranch[pnode->iip].lnum,
+ c->pnode_sz);
+}
+
+/**
+ * calc_nnode_num - calculate nnode number.
+ * @row: the row in the tree (root is zero)
+ * @col: the column in the row (leftmost is zero)
+ *
+ * The nnode number is a number that uniquely identifies a nnode and can be used
+ * easily to traverse the tree from the root to that nnode.
+ *
+ * This function calculates and returns the nnode number for the nnode at @row
+ * and @col.
+ */
+static int calc_nnode_num(int row, int col)
+{
+ int num, bits;
+
+ num = 1;
+ while (row--) {
+ bits = (col & (UBIFS_LPT_FANOUT - 1));
+ col >>= UBIFS_LPT_FANOUT_SHIFT;
+ num <<= UBIFS_LPT_FANOUT_SHIFT;
+ num |= bits;
+ }
+ return num;
+}
+
+/**
+ * calc_nnode_num_from_parent - calculate nnode number.
+ * @c: UBIFS file-system description object
+ * @parent: parent nnode
+ * @iip: index in parent
+ *
+ * The nnode number is a number that uniquely identifies a nnode and can be used
+ * easily to traverse the tree from the root to that nnode.
+ *
+ * This function calculates and returns the nnode number based on the parent's
+ * nnode number and the index in parent.
+ */
+static int calc_nnode_num_from_parent(struct ubifs_info *c,
+ struct ubifs_nnode *parent, int iip)
+{
+ int num, shft;
+
+ if (!parent)
+ return 1;
+ shft = (c->lpt_hght - parent->level) * UBIFS_LPT_FANOUT_SHIFT;
+ num = parent->num ^ (1 << shft);
+ num |= (UBIFS_LPT_FANOUT + iip) << shft;
+ return num;
+}
+
+/**
+ * calc_pnode_num_from_parent - calculate pnode number.
+ * @c: UBIFS file-system description object
+ * @parent: parent nnode
+ * @iip: index in parent
+ *
+ * The pnode number is a number that uniquely identifies a pnode and can be used
+ * easily to traverse the tree from the root to that pnode.
+ *
+ * This function calculates and returns the pnode number based on the parent's
+ * nnode number and the index in parent.
+ */
+static int calc_pnode_num_from_parent(struct ubifs_info *c,
+ struct ubifs_nnode *parent, int iip)
+{
+ int i, n = c->lpt_hght - 1, pnum = parent->num, num = 0;
+
+ for (i = 0; i < n; i++) {
+ num <<= UBIFS_LPT_FANOUT_SHIFT;
+ num |= pnum & (UBIFS_LPT_FANOUT - 1);
+ pnum >>= UBIFS_LPT_FANOUT_SHIFT;
+ }
+ num <<= UBIFS_LPT_FANOUT_SHIFT;
+ num |= iip;
+ return num;
+}
+
+/**
+ * ubifs_create_dflt_lpt - create default LPT.
+ * @c: UBIFS file-system description object
+ * @main_lebs: number of main area LEBs is passed and returned here
+ * @lpt_first: LEB number of first LPT LEB
+ * @lpt_lebs: number of LEBs for LPT is passed and returned here
+ * @big_lpt: use big LPT model is passed and returned here
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_create_dflt_lpt(struct ubifs_info *c, int *main_lebs, int lpt_first,
+ int *lpt_lebs, int *big_lpt)
+{
+ int lnum, err = 0, node_sz, iopos, i, j, cnt, len, alen, row;
+ int blnum, boffs, bsz, bcnt;
+ struct ubifs_pnode *pnode = NULL;
+ struct ubifs_nnode *nnode = NULL;
+ void *buf = NULL, *p;
+ struct ubifs_lpt_lprops *ltab = NULL;
+ int *lsave = NULL;
+
+ err = calc_dflt_lpt_geom(c, main_lebs, big_lpt);
+ if (err)
+ return err;
+ *lpt_lebs = c->lpt_lebs;
+
+ /* Needed by 'ubifs_pack_nnode()' and 'set_ltab()' */
+ c->lpt_first = lpt_first;
+ /* Needed by 'set_ltab()' */
+ c->lpt_last = lpt_first + c->lpt_lebs - 1;
+ /* Needed by 'ubifs_pack_lsave()' */
+ c->main_first = c->leb_cnt - *main_lebs;
+
+ lsave = kmalloc(sizeof(int) * c->lsave_cnt, GFP_KERNEL);
+ pnode = kzalloc(sizeof(struct ubifs_pnode), GFP_KERNEL);
+ nnode = kzalloc(sizeof(struct ubifs_nnode), GFP_KERNEL);
+ buf = vmalloc(c->leb_size);
+ ltab = vmalloc(sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
+ if (!pnode || !nnode || !buf || !ltab || !lsave) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ ubifs_assert(!c->ltab);
+ c->ltab = ltab; /* Needed by set_ltab */
+
+ /* Initialize LPT's own lprops */
+ for (i = 0; i < c->lpt_lebs; i++) {
+ ltab[i].free = c->leb_size;
+ ltab[i].dirty = 0;
+ ltab[i].tgc = 0;
+ ltab[i].cmt = 0;
+ }
+
+ lnum = lpt_first;
+ p = buf;
+ /* Number of leaf nodes (pnodes) */
+ cnt = c->pnode_cnt;
+
+ /*
+ * The first pnode contains the LEB properties for the LEBs that contain
+ * the root inode node and the root index node of the index tree.
+ */
+ node_sz = ALIGN(ubifs_idx_node_sz(c, 1), 8);
+ iopos = ALIGN(node_sz, c->min_io_size);
+ pnode->lprops[0].free = c->leb_size - iopos;
+ pnode->lprops[0].dirty = iopos - node_sz;
+ pnode->lprops[0].flags = LPROPS_INDEX;
+
+ node_sz = UBIFS_INO_NODE_SZ;
+ iopos = ALIGN(node_sz, c->min_io_size);
+ pnode->lprops[1].free = c->leb_size - iopos;
+ pnode->lprops[1].dirty = iopos - node_sz;
+
+ for (i = 2; i < UBIFS_LPT_FANOUT; i++)
+ pnode->lprops[i].free = c->leb_size;
+
+ /* Add first pnode */
+ ubifs_pack_pnode(c, p, pnode);
+ p += c->pnode_sz;
+ len = c->pnode_sz;
+ pnode->num += 1;
+
+ /* Reset pnode values for remaining pnodes */
+ pnode->lprops[0].free = c->leb_size;
+ pnode->lprops[0].dirty = 0;
+ pnode->lprops[0].flags = 0;
+
+ pnode->lprops[1].free = c->leb_size;
+ pnode->lprops[1].dirty = 0;
+
+ /*
+ * To calculate the internal node branches, we keep information about
+ * the level below.
+ */
+ blnum = lnum; /* LEB number of level below */
+ boffs = 0; /* Offset of level below */
+ bcnt = cnt; /* Number of nodes in level below */
+ bsz = c->pnode_sz; /* Size of nodes in level below */
+
+ /* Add all remaining pnodes */
+ for (i = 1; i < cnt; i++) {
+ if (len + c->pnode_sz > c->leb_size) {
+ alen = ALIGN(len, c->min_io_size);
+ set_ltab(c, lnum, c->leb_size - alen, alen - len);
+ memset(p, 0xff, alen - len);
+ err = ubi_leb_change(c->ubi, lnum++, buf, alen,
+ UBI_SHORTTERM);
+ if (err)
+ goto out;
+ p = buf;
+ len = 0;
+ }
+ ubifs_pack_pnode(c, p, pnode);
+ p += c->pnode_sz;
+ len += c->pnode_sz;
+ /*
+ * pnodes are simply numbered left to right starting at zero,
+ * which means the pnode number can be used easily to traverse
+ * down the tree to the corresponding pnode.
+ */
+ pnode->num += 1;
+ }
+
+ row = 0;
+ for (i = UBIFS_LPT_FANOUT; cnt > i; i <<= UBIFS_LPT_FANOUT_SHIFT)
+ row += 1;
+ /* Add all nnodes, one level at a time */
+ while (1) {
+ /* Number of internal nodes (nnodes) at next level */
+ cnt = DIV_ROUND_UP(cnt, UBIFS_LPT_FANOUT);
+ for (i = 0; i < cnt; i++) {
+ if (len + c->nnode_sz > c->leb_size) {
+ alen = ALIGN(len, c->min_io_size);
+ set_ltab(c, lnum, c->leb_size - alen,
+ alen - len);
+ memset(p, 0xff, alen - len);
+ err = ubi_leb_change(c->ubi, lnum++, buf, alen,
+ UBI_SHORTTERM);
+ if (err)
+ goto out;
+ p = buf;
+ len = 0;
+ }
+ /* Only 1 nnode at this level, so it is the root */
+ if (cnt == 1) {
+ c->lpt_lnum = lnum;
+ c->lpt_offs = len;
+ }
+ /* Set branches to the level below */
+ for (j = 0; j < UBIFS_LPT_FANOUT; j++) {
+ if (bcnt) {
+ if (boffs + bsz > c->leb_size) {
+ blnum += 1;
+ boffs = 0;
+ }
+ nnode->nbranch[j].lnum = blnum;
+ nnode->nbranch[j].offs = boffs;
+ boffs += bsz;
+ bcnt--;
+ } else {
+ nnode->nbranch[j].lnum = 0;
+ nnode->nbranch[j].offs = 0;
+ }
+ }
+ nnode->num = calc_nnode_num(row, i);
+ ubifs_pack_nnode(c, p, nnode);
+ p += c->nnode_sz;
+ len += c->nnode_sz;
+ }
+ /* Only 1 nnode at this level, so it is the root */
+ if (cnt == 1)
+ break;
+ /* Update the information about the level below */
+ bcnt = cnt;
+ bsz = c->nnode_sz;
+ row -= 1;
+ }
+
+ if (*big_lpt) {
+ /* Need to add LPT's save table */
+ if (len + c->lsave_sz > c->leb_size) {
+ alen = ALIGN(len, c->min_io_size);
+ set_ltab(c, lnum, c->leb_size - alen, alen - len);
+ memset(p, 0xff, alen - len);
+ err = ubi_leb_change(c->ubi, lnum++, buf, alen,
+ UBI_SHORTTERM);
+ if (err)
+ goto out;
+ p = buf;
+ len = 0;
+ }
+
+ c->lsave_lnum = lnum;
+ c->lsave_offs = len;
+
+ for (i = 0; i < c->lsave_cnt && i < *main_lebs; i++)
+ lsave[i] = c->main_first + i;
+ for (; i < c->lsave_cnt; i++)
+ lsave[i] = c->main_first;
+
+ ubifs_pack_lsave(c, p, lsave);
+ p += c->lsave_sz;
+ len += c->lsave_sz;
+ }
+
+ /* Need to add LPT's own LEB properties table */
+ if (len + c->ltab_sz > c->leb_size) {
+ alen = ALIGN(len, c->min_io_size);
+ set_ltab(c, lnum, c->leb_size - alen, alen - len);
+ memset(p, 0xff, alen - len);
+ err = ubi_leb_change(c->ubi, lnum++, buf, alen, UBI_SHORTTERM);
+ if (err)
+ goto out;
+ p = buf;
+ len = 0;
+ }
+
+ c->ltab_lnum = lnum;
+ c->ltab_offs = len;
+
+ /* Update ltab before packing it */
+ len += c->ltab_sz;
+ alen = ALIGN(len, c->min_io_size);
+ set_ltab(c, lnum, c->leb_size - alen, alen - len);
+
+ ubifs_pack_ltab(c, p, ltab);
+ p += c->ltab_sz;
+
+ /* Write remaining buffer */
+ memset(p, 0xff, alen - len);
+ err = ubi_leb_change(c->ubi, lnum, buf, alen, UBI_SHORTTERM);
+ if (err)
+ goto out;
+
+ c->nhead_lnum = lnum;
+ c->nhead_offs = ALIGN(len, c->min_io_size);
+
+ dbg_lp("space_bits %d", c->space_bits);
+ dbg_lp("lpt_lnum_bits %d", c->lpt_lnum_bits);
+ dbg_lp("lpt_offs_bits %d", c->lpt_offs_bits);
+ dbg_lp("lpt_spc_bits %d", c->lpt_spc_bits);
+ dbg_lp("pcnt_bits %d", c->pcnt_bits);
+ dbg_lp("lnum_bits %d", c->lnum_bits);
+ dbg_lp("pnode_sz %d", c->pnode_sz);
+ dbg_lp("nnode_sz %d", c->nnode_sz);
+ dbg_lp("ltab_sz %d", c->ltab_sz);
+ dbg_lp("lsave_sz %d", c->lsave_sz);
+ dbg_lp("lsave_cnt %d", c->lsave_cnt);
+ dbg_lp("lpt_hght %d", c->lpt_hght);
+ dbg_lp("big_lpt %d", c->big_lpt);
+ dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs);
+ dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs);
+ dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs);
+ if (c->big_lpt)
+ dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs);
+out:
+ c->ltab = NULL;
+ kfree(lsave);
+ vfree(ltab);
+ vfree(buf);
+ kfree(nnode);
+ kfree(pnode);
+ return err;
+}
+
+/**
+ * update_cats - add LEB properties of a pnode to LEB category lists and heaps.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode
+ *
+ * When a pnode is loaded into memory, the LEB properties it contains are added,
+ * by this function, to the LEB category lists and heaps.
+ */
+static void update_cats(struct ubifs_info *c, struct ubifs_pnode *pnode)
+{
+ int i;
+
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ int cat = pnode->lprops[i].flags & LPROPS_CAT_MASK;
+ int lnum = pnode->lprops[i].lnum;
+
+ if (!lnum)
+ return;
+ ubifs_add_to_cat(c, &pnode->lprops[i], cat);
+ }
+}
+
+/**
+ * replace_cats - add LEB properties of a pnode to LEB category lists and heaps.
+ * @c: UBIFS file-system description object
+ * @old_pnode: pnode copied
+ * @new_pnode: pnode copy
+ *
+ * During commit it is sometimes necessary to copy a pnode
+ * (see dirty_cow_pnode). When that happens, references in
+ * category lists and heaps must be replaced. This function does that.
+ */
+static void replace_cats(struct ubifs_info *c, struct ubifs_pnode *old_pnode,
+ struct ubifs_pnode *new_pnode)
+{
+ int i;
+
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ if (!new_pnode->lprops[i].lnum)
+ return;
+ ubifs_replace_cat(c, &old_pnode->lprops[i],
+ &new_pnode->lprops[i]);
+ }
+}
+
+/**
+ * check_lpt_crc - check LPT node crc is correct.
+ * @c: UBIFS file-system description object
+ * @buf: buffer containing node
+ * @len: length of node
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int check_lpt_crc(void *buf, int len)
+{
+ int pos = 0;
+ uint8_t *addr = buf;
+ uint16_t crc, calc_crc;
+
+ crc = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_CRC_BITS);
+ calc_crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
+ len - UBIFS_LPT_CRC_BYTES);
+ if (crc != calc_crc) {
+ ubifs_err("invalid crc in LPT node: crc %hx calc %hx", crc,
+ calc_crc);
+ dbg_dump_stack();
+ return -EINVAL;
+ }
+ return 0;
+}
+
+/**
+ * check_lpt_type - check LPT node type is correct.
+ * @c: UBIFS file-system description object
+ * @addr: address of type bit field is passed and returned updated here
+ * @pos: position of type bit field is passed and returned updated here
+ * @type: expected type
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int check_lpt_type(uint8_t **addr, int *pos, int type)
+{
+ int node_type;
+
+ node_type = ubifs_unpack_bits(addr, pos, UBIFS_LPT_TYPE_BITS);
+ if (node_type != type) {
+ ubifs_err("invalid type (%d) in LPT node type %d", node_type,
+ type);
+ dbg_dump_stack();
+ return -EINVAL;
+ }
+ return 0;
+}
+
+/**
+ * unpack_pnode - unpack a pnode.
+ * @c: UBIFS file-system description object
+ * @buf: buffer containing packed pnode to unpack
+ * @pnode: pnode structure to fill
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int unpack_pnode(struct ubifs_info *c, void *buf,
+ struct ubifs_pnode *pnode)
+{
+ uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+ int i, pos = 0, err;
+
+ err = check_lpt_type(&addr, &pos, UBIFS_LPT_PNODE);
+ if (err)
+ return err;
+ if (c->big_lpt)
+ pnode->num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits);
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ struct ubifs_lprops * const lprops = &pnode->lprops[i];
+
+ lprops->free = ubifs_unpack_bits(&addr, &pos, c->space_bits);
+ lprops->free <<= 3;
+ lprops->dirty = ubifs_unpack_bits(&addr, &pos, c->space_bits);
+ lprops->dirty <<= 3;
+
+ if (ubifs_unpack_bits(&addr, &pos, 1))
+ lprops->flags = LPROPS_INDEX;
+ else
+ lprops->flags = 0;
+ lprops->flags |= ubifs_categorize_lprops(c, lprops);
+ }
+ err = check_lpt_crc(buf, c->pnode_sz);
+ return err;
+}
+
+/**
+ * unpack_nnode - unpack a nnode.
+ * @c: UBIFS file-system description object
+ * @buf: buffer containing packed nnode to unpack
+ * @nnode: nnode structure to fill
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int unpack_nnode(struct ubifs_info *c, void *buf,
+ struct ubifs_nnode *nnode)
+{
+ uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+ int i, pos = 0, err;
+
+ err = check_lpt_type(&addr, &pos, UBIFS_LPT_NNODE);
+ if (err)
+ return err;
+ if (c->big_lpt)
+ nnode->num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits);
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ int lnum;
+
+ lnum = ubifs_unpack_bits(&addr, &pos, c->lpt_lnum_bits) +
+ c->lpt_first;
+ if (lnum == c->lpt_last + 1)
+ lnum = 0;
+ nnode->nbranch[i].lnum = lnum;
+ nnode->nbranch[i].offs = ubifs_unpack_bits(&addr, &pos,
+ c->lpt_offs_bits);
+ }
+ err = check_lpt_crc(buf, c->nnode_sz);
+ return err;
+}
+
+/**
+ * unpack_ltab - unpack the LPT's own lprops table.
+ * @c: UBIFS file-system description object
+ * @buf: buffer from which to unpack
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int unpack_ltab(struct ubifs_info *c, void *buf)
+{
+ uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+ int i, pos = 0, err;
+
+ err = check_lpt_type(&addr, &pos, UBIFS_LPT_LTAB);
+ if (err)
+ return err;
+ for (i = 0; i < c->lpt_lebs; i++) {
+ int free = ubifs_unpack_bits(&addr, &pos, c->lpt_spc_bits);
+ int dirty = ubifs_unpack_bits(&addr, &pos, c->lpt_spc_bits);
+
+ if (free < 0 || free > c->leb_size || dirty < 0 ||
+ dirty > c->leb_size || free + dirty > c->leb_size)
+ return -EINVAL;
+
+ c->ltab[i].free = free;
+ c->ltab[i].dirty = dirty;
+ c->ltab[i].tgc = 0;
+ c->ltab[i].cmt = 0;
+ }
+ err = check_lpt_crc(buf, c->ltab_sz);
+ return err;
+}
+
+/**
+ * unpack_lsave - unpack the LPT's save table.
+ * @c: UBIFS file-system description object
+ * @buf: buffer from which to unpack
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int unpack_lsave(struct ubifs_info *c, void *buf)
+{
+ uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+ int i, pos = 0, err;
+
+ err = check_lpt_type(&addr, &pos, UBIFS_LPT_LSAVE);
+ if (err)
+ return err;
+ for (i = 0; i < c->lsave_cnt; i++) {
+ int lnum = ubifs_unpack_bits(&addr, &pos, c->lnum_bits);
+
+ if (lnum < c->main_first || lnum >= c->leb_cnt)
+ return -EINVAL;
+ c->lsave[i] = lnum;
+ }
+ err = check_lpt_crc(buf, c->lsave_sz);
+ return err;
+}
+
+/**
+ * validate_nnode - validate a nnode.
+ * @c: UBIFS file-system description object
+ * @nnode: nnode to validate
+ * @parent: parent nnode (or NULL for the root nnode)
+ * @iip: index in parent
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int validate_nnode(struct ubifs_info *c, struct ubifs_nnode *nnode,
+ struct ubifs_nnode *parent, int iip)
+{
+ int i, lvl, max_offs;
+
+ if (c->big_lpt) {
+ int num = calc_nnode_num_from_parent(c, parent, iip);
+
+ if (nnode->num != num)
+ return -EINVAL;
+ }
+ lvl = parent ? parent->level - 1 : c->lpt_hght;
+ if (lvl < 1)
+ return -EINVAL;
+ if (lvl == 1)
+ max_offs = c->leb_size - c->pnode_sz;
+ else
+ max_offs = c->leb_size - c->nnode_sz;
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ int lnum = nnode->nbranch[i].lnum;
+ int offs = nnode->nbranch[i].offs;
+
+ if (lnum == 0) {
+ if (offs != 0)
+ return -EINVAL;
+ continue;
+ }
+ if (lnum < c->lpt_first || lnum > c->lpt_last)
+ return -EINVAL;
+ if (offs < 0 || offs > max_offs)
+ return -EINVAL;
+ }
+ return 0;
+}
+
+/**
+ * validate_pnode - validate a pnode.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode to validate
+ * @parent: parent nnode
+ * @iip: index in parent
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int validate_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
+ struct ubifs_nnode *parent, int iip)
+{
+ int i;
+
+ if (c->big_lpt) {
+ int num = calc_pnode_num_from_parent(c, parent, iip);
+
+ if (pnode->num != num)
+ return -EINVAL;
+ }
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ int free = pnode->lprops[i].free;
+ int dirty = pnode->lprops[i].dirty;
+
+ if (free < 0 || free > c->leb_size || free % c->min_io_size ||
+ (free & 7))
+ return -EINVAL;
+ if (dirty < 0 || dirty > c->leb_size || (dirty & 7))
+ return -EINVAL;
+ if (dirty + free > c->leb_size)
+ return -EINVAL;
+ }
+ return 0;
+}
+
+/**
+ * set_pnode_lnum - set LEB numbers on a pnode.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode to update
+ *
+ * This function calculates the LEB numbers for the LEB properties it contains
+ * based on the pnode number.
+ */
+static void set_pnode_lnum(struct ubifs_info *c, struct ubifs_pnode *pnode)
+{
+ int i, lnum;
+
+ lnum = (pnode->num << UBIFS_LPT_FANOUT_SHIFT) + c->main_first;
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ if (lnum >= c->leb_cnt)
+ return;
+ pnode->lprops[i].lnum = lnum++;
+ }
+}
+
+/**
+ * ubifs_read_nnode - read a nnode from flash and link it to the tree in memory.
+ * @c: UBIFS file-system description object
+ * @parent: parent nnode (or NULL for the root)
+ * @iip: index in parent
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_read_nnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip)
+{
+ struct ubifs_nbranch *branch = NULL;
+ struct ubifs_nnode *nnode = NULL;
+ void *buf = c->lpt_nod_buf;
+ int err, lnum, offs;
+
+ if (parent) {
+ branch = &parent->nbranch[iip];
+ lnum = branch->lnum;
+ offs = branch->offs;
+ } else {
+ lnum = c->lpt_lnum;
+ offs = c->lpt_offs;
+ }
+ nnode = kzalloc(sizeof(struct ubifs_nnode), GFP_NOFS);
+ if (!nnode) {
+ err = -ENOMEM;
+ goto out;
+ }
+ if (lnum == 0) {
+ /*
+ * This nnode was not written which just means that the LEB
+ * properties in the subtree below it describe empty LEBs. We
+ * make the nnode as though we had read it, which in fact means
+ * doing almost nothing.
+ */
+ if (c->big_lpt)
+ nnode->num = calc_nnode_num_from_parent(c, parent, iip);
+ } else {
+ err = ubi_read(c->ubi, lnum, buf, offs, c->nnode_sz);
+ if (err)
+ goto out;
+ err = unpack_nnode(c, buf, nnode);
+ if (err)
+ goto out;
+ }
+ err = validate_nnode(c, nnode, parent, iip);
+ if (err)
+ goto out;
+ if (!c->big_lpt)
+ nnode->num = calc_nnode_num_from_parent(c, parent, iip);
+ if (parent) {
+ branch->nnode = nnode;
+ nnode->level = parent->level - 1;
+ } else {
+ c->nroot = nnode;
+ nnode->level = c->lpt_hght;
+ }
+ nnode->parent = parent;
+ nnode->iip = iip;
+ return 0;
+
+out:
+ ubifs_err("error %d reading nnode at %d:%d", err, lnum, offs);
+ kfree(nnode);
+ return err;
+}
+
+/**
+ * read_pnode - read a pnode from flash and link it to the tree in memory.
+ * @c: UBIFS file-system description object
+ * @parent: parent nnode
+ * @iip: index in parent
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int read_pnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip)
+{
+ struct ubifs_nbranch *branch;
+ struct ubifs_pnode *pnode = NULL;
+ void *buf = c->lpt_nod_buf;
+ int err, lnum, offs;
+
+ branch = &parent->nbranch[iip];
+ lnum = branch->lnum;
+ offs = branch->offs;
+ pnode = kzalloc(sizeof(struct ubifs_pnode), GFP_NOFS);
+ if (!pnode) {
+ err = -ENOMEM;
+ goto out;
+ }
+ if (lnum == 0) {
+ /*
+ * This pnode was not written which just means that the LEB
+ * properties in it describe empty LEBs. We make the pnode as
+ * though we had read it.
+ */
+ int i;
+
+ if (c->big_lpt)
+ pnode->num = calc_pnode_num_from_parent(c, parent, iip);
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ struct ubifs_lprops * const lprops = &pnode->lprops[i];
+
+ lprops->free = c->leb_size;
+ lprops->flags = ubifs_categorize_lprops(c, lprops);
+ }
+ } else {
+ err = ubi_read(c->ubi, lnum, buf, offs, c->pnode_sz);
+ if (err)
+ goto out;
+ err = unpack_pnode(c, buf, pnode);
+ if (err)
+ goto out;
+ }
+ err = validate_pnode(c, pnode, parent, iip);
+ if (err)
+ goto out;
+ if (!c->big_lpt)
+ pnode->num = calc_pnode_num_from_parent(c, parent, iip);
+ branch->pnode = pnode;
+ pnode->parent = parent;
+ pnode->iip = iip;
+ set_pnode_lnum(c, pnode);
+ c->pnodes_have += 1;
+ return 0;
+
+out:
+ ubifs_err("error %d reading pnode at %d:%d", err, lnum, offs);
+ dbg_dump_pnode(c, pnode, parent, iip);
+ dbg_msg("calc num: %d", calc_pnode_num_from_parent(c, parent, iip));
+ kfree(pnode);
+ return err;
+}
+
+/**
+ * read_ltab - read LPT's own lprops table.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int read_ltab(struct ubifs_info *c)
+{
+ int err;
+ void *buf;
+
+ buf = vmalloc(c->ltab_sz);
+ if (!buf)
+ return -ENOMEM;
+ err = ubi_read(c->ubi, c->ltab_lnum, buf, c->ltab_offs, c->ltab_sz);
+ if (err)
+ goto out;
+ err = unpack_ltab(c, buf);
+out:
+ vfree(buf);
+ return err;
+}
+
+/**
+ * read_lsave - read LPT's save table.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int read_lsave(struct ubifs_info *c)
+{
+ int err, i;
+ void *buf;
+
+ buf = vmalloc(c->lsave_sz);
+ if (!buf)
+ return -ENOMEM;
+ err = ubi_read(c->ubi, c->lsave_lnum, buf, c->lsave_offs, c->lsave_sz);
+ if (err)
+ goto out;
+ err = unpack_lsave(c, buf);
+ if (err)
+ goto out;
+ for (i = 0; i < c->lsave_cnt; i++) {
+ int lnum = c->lsave[i];
+
+ /*
+ * Due to automatic resizing, the values in the lsave table
+ * could be beyond the volume size - just ignore them.
+ */
+ if (lnum >= c->leb_cnt)
+ continue;
+ ubifs_lpt_lookup(c, lnum);
+ }
+out:
+ vfree(buf);
+ return err;
+}
+
+/**
+ * ubifs_get_nnode - get a nnode.
+ * @c: UBIFS file-system description object
+ * @parent: parent nnode (or NULL for the root)
+ * @iip: index in parent
+ *
+ * This function returns a pointer to the nnode on success or a negative error
+ * code on failure.
+ */
+struct ubifs_nnode *ubifs_get_nnode(struct ubifs_info *c,
+ struct ubifs_nnode *parent, int iip)
+{
+ struct ubifs_nbranch *branch;
+ struct ubifs_nnode *nnode;
+ int err;
+
+ branch = &parent->nbranch[iip];
+ nnode = branch->nnode;
+ if (nnode)
+ return nnode;
+ err = ubifs_read_nnode(c, parent, iip);
+ if (err)
+ return ERR_PTR(err);
+ return branch->nnode;
+}
+
+/**
+ * ubifs_get_pnode - get a pnode.
+ * @c: UBIFS file-system description object
+ * @parent: parent nnode
+ * @iip: index in parent
+ *
+ * This function returns a pointer to the pnode on success or a negative error
+ * code on failure.
+ */
+struct ubifs_pnode *ubifs_get_pnode(struct ubifs_info *c,
+ struct ubifs_nnode *parent, int iip)
+{
+ struct ubifs_nbranch *branch;
+ struct ubifs_pnode *pnode;
+ int err;
+
+ branch = &parent->nbranch[iip];
+ pnode = branch->pnode;
+ if (pnode)
+ return pnode;
+ err = read_pnode(c, parent, iip);
+ if (err)
+ return ERR_PTR(err);
+ update_cats(c, branch->pnode);
+ return branch->pnode;
+}
+
+/**
+ * ubifs_lpt_lookup - lookup LEB properties in the LPT.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to lookup
+ *
+ * This function returns a pointer to the LEB properties on success or a
+ * negative error code on failure.
+ */
+struct ubifs_lprops *ubifs_lpt_lookup(struct ubifs_info *c, int lnum)
+{
+ int err, i, h, iip, shft;
+ struct ubifs_nnode *nnode;
+ struct ubifs_pnode *pnode;
+
+ if (!c->nroot) {
+ err = ubifs_read_nnode(c, NULL, 0);
+ if (err)
+ return ERR_PTR(err);
+ }
+ nnode = c->nroot;
+ i = lnum - c->main_first;
+ shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
+ for (h = 1; h < c->lpt_hght; h++) {
+ iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
+ shft -= UBIFS_LPT_FANOUT_SHIFT;
+ nnode = ubifs_get_nnode(c, nnode, iip);
+ if (IS_ERR(nnode))
+ return ERR_PTR(PTR_ERR(nnode));
+ }
+ iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
+ shft -= UBIFS_LPT_FANOUT_SHIFT;
+ pnode = ubifs_get_pnode(c, nnode, iip);
+ if (IS_ERR(pnode))
+ return ERR_PTR(PTR_ERR(pnode));
+ iip = (i & (UBIFS_LPT_FANOUT - 1));
+ dbg_lp("LEB %d, free %d, dirty %d, flags %d", lnum,
+ pnode->lprops[iip].free, pnode->lprops[iip].dirty,
+ pnode->lprops[iip].flags);
+ return &pnode->lprops[iip];
+}
+
+/**
+ * dirty_cow_nnode - ensure a nnode is not being committed.
+ * @c: UBIFS file-system description object
+ * @nnode: nnode to check
+ *
+ * Returns dirtied nnode on success or negative error code on failure.
+ */
+static struct ubifs_nnode *dirty_cow_nnode(struct ubifs_info *c,
+ struct ubifs_nnode *nnode)
+{
+ struct ubifs_nnode *n;
+ int i;
+
+ if (!test_bit(COW_CNODE, &nnode->flags)) {
+ /* nnode is not being committed */
+ if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
+ c->dirty_nn_cnt += 1;
+ ubifs_add_nnode_dirt(c, nnode);
+ }
+ return nnode;
+ }
+
+ /* nnode is being committed, so copy it */
+ n = kmalloc(sizeof(struct ubifs_nnode), GFP_NOFS);
+ if (unlikely(!n))
+ return ERR_PTR(-ENOMEM);
+
+ memcpy(n, nnode, sizeof(struct ubifs_nnode));
+ n->cnext = NULL;
+ __set_bit(DIRTY_CNODE, &n->flags);
+ __clear_bit(COW_CNODE, &n->flags);
+
+ /* The children now have new parent */
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ struct ubifs_nbranch *branch = &n->nbranch[i];
+
+ if (branch->cnode)
+ branch->cnode->parent = n;
+ }
+
+ ubifs_assert(!test_bit(OBSOLETE_CNODE, &nnode->flags));
+ __set_bit(OBSOLETE_CNODE, &nnode->flags);
+
+ c->dirty_nn_cnt += 1;
+ ubifs_add_nnode_dirt(c, nnode);
+ if (nnode->parent)
+ nnode->parent->nbranch[n->iip].nnode = n;
+ else
+ c->nroot = n;
+ return n;
+}
+
+/**
+ * dirty_cow_pnode - ensure a pnode is not being committed.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode to check
+ *
+ * Returns dirtied pnode on success or negative error code on failure.
+ */
+static struct ubifs_pnode *dirty_cow_pnode(struct ubifs_info *c,
+ struct ubifs_pnode *pnode)
+{
+ struct ubifs_pnode *p;
+
+ if (!test_bit(COW_CNODE, &pnode->flags)) {
+ /* pnode is not being committed */
+ if (!test_and_set_bit(DIRTY_CNODE, &pnode->flags)) {
+ c->dirty_pn_cnt += 1;
+ add_pnode_dirt(c, pnode);
+ }
+ return pnode;
+ }
+
+ /* pnode is being committed, so copy it */
+ p = kmalloc(sizeof(struct ubifs_pnode), GFP_NOFS);
+ if (unlikely(!p))
+ return ERR_PTR(-ENOMEM);
+
+ memcpy(p, pnode, sizeof(struct ubifs_pnode));
+ p->cnext = NULL;
+ __set_bit(DIRTY_CNODE, &p->flags);
+ __clear_bit(COW_CNODE, &p->flags);
+ replace_cats(c, pnode, p);
+
+ ubifs_assert(!test_bit(OBSOLETE_CNODE, &pnode->flags));
+ __set_bit(OBSOLETE_CNODE, &pnode->flags);
+
+ c->dirty_pn_cnt += 1;
+ add_pnode_dirt(c, pnode);
+ pnode->parent->nbranch[p->iip].pnode = p;
+ return p;
+}
+
+/**
+ * ubifs_lpt_lookup_dirty - lookup LEB properties in the LPT.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to lookup
+ *
+ * This function returns a pointer to the LEB properties on success or a
+ * negative error code on failure.
+ */
+struct ubifs_lprops *ubifs_lpt_lookup_dirty(struct ubifs_info *c, int lnum)
+{
+ int err, i, h, iip, shft;
+ struct ubifs_nnode *nnode;
+ struct ubifs_pnode *pnode;
+
+ if (!c->nroot) {
+ err = ubifs_read_nnode(c, NULL, 0);
+ if (err)
+ return ERR_PTR(err);
+ }
+ nnode = c->nroot;
+ nnode = dirty_cow_nnode(c, nnode);
+ if (IS_ERR(nnode))
+ return ERR_PTR(PTR_ERR(nnode));
+ i = lnum - c->main_first;
+ shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
+ for (h = 1; h < c->lpt_hght; h++) {
+ iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
+ shft -= UBIFS_LPT_FANOUT_SHIFT;
+ nnode = ubifs_get_nnode(c, nnode, iip);
+ if (IS_ERR(nnode))
+ return ERR_PTR(PTR_ERR(nnode));
+ nnode = dirty_cow_nnode(c, nnode);
+ if (IS_ERR(nnode))
+ return ERR_PTR(PTR_ERR(nnode));
+ }
+ iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
+ shft -= UBIFS_LPT_FANOUT_SHIFT;
+ pnode = ubifs_get_pnode(c, nnode, iip);
+ if (IS_ERR(pnode))
+ return ERR_PTR(PTR_ERR(pnode));
+ pnode = dirty_cow_pnode(c, pnode);
+ if (IS_ERR(pnode))
+ return ERR_PTR(PTR_ERR(pnode));
+ iip = (i & (UBIFS_LPT_FANOUT - 1));
+ dbg_lp("LEB %d, free %d, dirty %d, flags %d", lnum,
+ pnode->lprops[iip].free, pnode->lprops[iip].dirty,
+ pnode->lprops[iip].flags);
+ ubifs_assert(test_bit(DIRTY_CNODE, &pnode->flags));
+ return &pnode->lprops[iip];
+}
+
+/**
+ * lpt_init_rd - initialize the LPT for reading.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int lpt_init_rd(struct ubifs_info *c)
+{
+ int err, i;
+
+ c->ltab = vmalloc(sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
+ if (!c->ltab)
+ return -ENOMEM;
+
+ i = max_t(int, c->nnode_sz, c->pnode_sz);
+ c->lpt_nod_buf = kmalloc(i, GFP_KERNEL);
+ if (!c->lpt_nod_buf)
+ return -ENOMEM;
+
+ for (i = 0; i < LPROPS_HEAP_CNT; i++) {
+ c->lpt_heap[i].arr = kmalloc(sizeof(void *) * LPT_HEAP_SZ,
+ GFP_KERNEL);
+ if (!c->lpt_heap[i].arr)
+ return -ENOMEM;
+ c->lpt_heap[i].cnt = 0;
+ c->lpt_heap[i].max_cnt = LPT_HEAP_SZ;
+ }
+
+ c->dirty_idx.arr = kmalloc(sizeof(void *) * LPT_HEAP_SZ, GFP_KERNEL);
+ if (!c->dirty_idx.arr)
+ return -ENOMEM;
+ c->dirty_idx.cnt = 0;
+ c->dirty_idx.max_cnt = LPT_HEAP_SZ;
+
+ err = read_ltab(c);
+ if (err)
+ return err;
+
+ dbg_lp("space_bits %d", c->space_bits);
+ dbg_lp("lpt_lnum_bits %d", c->lpt_lnum_bits);
+ dbg_lp("lpt_offs_bits %d", c->lpt_offs_bits);
+ dbg_lp("lpt_spc_bits %d", c->lpt_spc_bits);
+ dbg_lp("pcnt_bits %d", c->pcnt_bits);
+ dbg_lp("lnum_bits %d", c->lnum_bits);
+ dbg_lp("pnode_sz %d", c->pnode_sz);
+ dbg_lp("nnode_sz %d", c->nnode_sz);
+ dbg_lp("ltab_sz %d", c->ltab_sz);
+ dbg_lp("lsave_sz %d", c->lsave_sz);
+ dbg_lp("lsave_cnt %d", c->lsave_cnt);
+ dbg_lp("lpt_hght %d", c->lpt_hght);
+ dbg_lp("big_lpt %d", c->big_lpt);
+ dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs);
+ dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs);
+ dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs);
+ if (c->big_lpt)
+ dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs);
+
+ return 0;
+}
+
+/**
+ * lpt_init_wr - initialize the LPT for writing.
+ * @c: UBIFS file-system description object
+ *
+ * 'lpt_init_rd()' must have been called already.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int lpt_init_wr(struct ubifs_info *c)
+{
+ int err, i;
+
+ c->ltab_cmt = vmalloc(sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
+ if (!c->ltab_cmt)
+ return -ENOMEM;
+
+ c->lpt_buf = vmalloc(c->leb_size);
+ if (!c->lpt_buf)
+ return -ENOMEM;
+
+ if (c->big_lpt) {
+ c->lsave = kmalloc(sizeof(int) * c->lsave_cnt, GFP_NOFS);
+ if (!c->lsave)
+ return -ENOMEM;
+ err = read_lsave(c);
+ if (err)
+ return err;
+ }
+
+ for (i = 0; i < c->lpt_lebs; i++)
+ if (c->ltab[i].free == c->leb_size) {
+ err = ubifs_leb_unmap(c, i + c->lpt_first);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
+/**
+ * ubifs_lpt_init - initialize the LPT.
+ * @c: UBIFS file-system description object
+ * @rd: whether to initialize lpt for reading
+ * @wr: whether to initialize lpt for writing
+ *
+ * For mounting 'rw', @rd and @wr are both true. For mounting 'ro', @rd is true
+ * and @wr is false. For mounting from 'ro' to 'rw', @rd is false and @wr is
+ * true.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_lpt_init(struct ubifs_info *c, int rd, int wr)
+{
+ int err;
+
+ if (rd) {
+ err = lpt_init_rd(c);
+ if (err)
+ return err;
+ }
+
+ if (wr) {
+ err = lpt_init_wr(c);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
+/**
+ * struct lpt_scan_node - somewhere to put nodes while we scan LPT.
+ * @nnode: where to keep a nnode
+ * @pnode: where to keep a pnode
+ * @cnode: where to keep a cnode
+ * @in_tree: is the node in the tree in memory
+ * @ptr.nnode: pointer to the nnode (if it is an nnode) which may be here or in
+ * the tree
+ * @ptr.pnode: ditto for pnode
+ * @ptr.cnode: ditto for cnode
+ */
+struct lpt_scan_node {
+ union {
+ struct ubifs_nnode nnode;
+ struct ubifs_pnode pnode;
+ struct ubifs_cnode cnode;
+ };
+ int in_tree;
+ union {
+ struct ubifs_nnode *nnode;
+ struct ubifs_pnode *pnode;
+ struct ubifs_cnode *cnode;
+ } ptr;
+};
+
+/**
+ * scan_get_nnode - for the scan, get a nnode from either the tree or flash.
+ * @c: the UBIFS file-system description object
+ * @path: where to put the nnode
+ * @parent: parent of the nnode
+ * @iip: index in parent of the nnode
+ *
+ * This function returns a pointer to the nnode on success or a negative error
+ * code on failure.
+ */
+static struct ubifs_nnode *scan_get_nnode(struct ubifs_info *c,
+ struct lpt_scan_node *path,
+ struct ubifs_nnode *parent, int iip)
+{
+ struct ubifs_nbranch *branch;
+ struct ubifs_nnode *nnode;
+ void *buf = c->lpt_nod_buf;
+ int err;
+
+ branch = &parent->nbranch[iip];
+ nnode = branch->nnode;
+ if (nnode) {
+ path->in_tree = 1;
+ path->ptr.nnode = nnode;
+ return nnode;
+ }
+ nnode = &path->nnode;
+ path->in_tree = 0;
+ path->ptr.nnode = nnode;
+ memset(nnode, 0, sizeof(struct ubifs_nnode));
+ if (branch->lnum == 0) {
+ /*
+ * This nnode was not written which just means that the LEB
+ * properties in the subtree below it describe empty LEBs. We
+ * make the nnode as though we had read it, which in fact means
+ * doing almost nothing.
+ */
+ if (c->big_lpt)
+ nnode->num = calc_nnode_num_from_parent(c, parent, iip);
+ } else {
+ err = ubi_read(c->ubi, branch->lnum, buf, branch->offs,
+ c->nnode_sz);
+ if (err)
+ return ERR_PTR(err);
+ err = unpack_nnode(c, buf, nnode);
+ if (err)
+ return ERR_PTR(err);
+ }
+ err = validate_nnode(c, nnode, parent, iip);
+ if (err)
+ return ERR_PTR(err);
+ if (!c->big_lpt)
+ nnode->num = calc_nnode_num_from_parent(c, parent, iip);
+ nnode->level = parent->level - 1;
+ nnode->parent = parent;
+ nnode->iip = iip;
+ return nnode;
+}
+
+/**
+ * scan_get_pnode - for the scan, get a pnode from either the tree or flash.
+ * @c: the UBIFS file-system description object
+ * @path: where to put the pnode
+ * @parent: parent of the pnode
+ * @iip: index in parent of the pnode
+ *
+ * This function returns a pointer to the pnode on success or a negative error
+ * code on failure.
+ */
+static struct ubifs_pnode *scan_get_pnode(struct ubifs_info *c,
+ struct lpt_scan_node *path,
+ struct ubifs_nnode *parent, int iip)
+{
+ struct ubifs_nbranch *branch;
+ struct ubifs_pnode *pnode;
+ void *buf = c->lpt_nod_buf;
+ int err;
+
+ branch = &parent->nbranch[iip];
+ pnode = branch->pnode;
+ if (pnode) {
+ path->in_tree = 1;
+ path->ptr.pnode = pnode;
+ return pnode;
+ }
+ pnode = &path->pnode;
+ path->in_tree = 0;
+ path->ptr.pnode = pnode;
+ memset(pnode, 0, sizeof(struct ubifs_pnode));
+ if (branch->lnum == 0) {
+ /*
+ * This pnode was not written which just means that the LEB
+ * properties in it describe empty LEBs. We make the pnode as
+ * though we had read it.
+ */
+ int i;
+
+ if (c->big_lpt)
+ pnode->num = calc_pnode_num_from_parent(c, parent, iip);
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ struct ubifs_lprops * const lprops = &pnode->lprops[i];
+
+ lprops->free = c->leb_size;
+ lprops->flags = ubifs_categorize_lprops(c, lprops);
+ }
+ } else {
+ ubifs_assert(branch->lnum >= c->lpt_first &&
+ branch->lnum <= c->lpt_last);
+ ubifs_assert(branch->offs >= 0 && branch->offs < c->leb_size);
+ err = ubi_read(c->ubi, branch->lnum, buf, branch->offs,
+ c->pnode_sz);
+ if (err)
+ return ERR_PTR(err);
+ err = unpack_pnode(c, buf, pnode);
+ if (err)
+ return ERR_PTR(err);
+ }
+ err = validate_pnode(c, pnode, parent, iip);
+ if (err)
+ return ERR_PTR(err);
+ if (!c->big_lpt)
+ pnode->num = calc_pnode_num_from_parent(c, parent, iip);
+ pnode->parent = parent;
+ pnode->iip = iip;
+ set_pnode_lnum(c, pnode);
+ return pnode;
+}
+
+/**
+ * ubifs_lpt_scan_nolock - scan the LPT.
+ * @c: the UBIFS file-system description object
+ * @start_lnum: LEB number from which to start scanning
+ * @end_lnum: LEB number at which to stop scanning
+ * @scan_cb: callback function called for each lprops
+ * @data: data to be passed to the callback function
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_lpt_scan_nolock(struct ubifs_info *c, int start_lnum, int end_lnum,
+ ubifs_lpt_scan_callback scan_cb, void *data)
+{
+ int err = 0, i, h, iip, shft;
+ struct ubifs_nnode *nnode;
+ struct ubifs_pnode *pnode;
+ struct lpt_scan_node *path;
+
+ if (start_lnum == -1) {
+ start_lnum = end_lnum + 1;
+ if (start_lnum >= c->leb_cnt)
+ start_lnum = c->main_first;
+ }
+
+ ubifs_assert(start_lnum >= c->main_first && start_lnum < c->leb_cnt);
+ ubifs_assert(end_lnum >= c->main_first && end_lnum < c->leb_cnt);
+
+ if (!c->nroot) {
+ err = ubifs_read_nnode(c, NULL, 0);
+ if (err)
+ return err;
+ }
+
+ path = kmalloc(sizeof(struct lpt_scan_node) * (c->lpt_hght + 1),
+ GFP_NOFS);
+ if (!path)
+ return -ENOMEM;
+
+ path[0].ptr.nnode = c->nroot;
+ path[0].in_tree = 1;
+again:
+ /* Descend to the pnode containing start_lnum */
+ nnode = c->nroot;
+ i = start_lnum - c->main_first;
+ shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
+ for (h = 1; h < c->lpt_hght; h++) {
+ iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
+ shft -= UBIFS_LPT_FANOUT_SHIFT;
+ nnode = scan_get_nnode(c, path + h, nnode, iip);
+ if (IS_ERR(nnode)) {
+ err = PTR_ERR(nnode);
+ goto out;
+ }
+ }
+ iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
+ shft -= UBIFS_LPT_FANOUT_SHIFT;
+ pnode = scan_get_pnode(c, path + h, nnode, iip);
+ if (IS_ERR(pnode)) {
+ err = PTR_ERR(pnode);
+ goto out;
+ }
+ iip = (i & (UBIFS_LPT_FANOUT - 1));
+
+ /* Loop for each lprops */
+ while (1) {
+ struct ubifs_lprops *lprops = &pnode->lprops[iip];
+ int ret, lnum = lprops->lnum;
+
+ ret = scan_cb(c, lprops, path[h].in_tree, data);
+ if (ret < 0) {
+ err = ret;
+ goto out;
+ }
+ if (ret & LPT_SCAN_ADD) {
+ /* Add all the nodes in path to the tree in memory */
+ for (h = 1; h < c->lpt_hght; h++) {
+ const size_t sz = sizeof(struct ubifs_nnode);
+ struct ubifs_nnode *parent;
+
+ if (path[h].in_tree)
+ continue;
+ nnode = kmalloc(sz, GFP_NOFS);
+ if (!nnode) {
+ err = -ENOMEM;
+ goto out;
+ }
+ memcpy(nnode, &path[h].nnode, sz);
+ parent = nnode->parent;
+ parent->nbranch[nnode->iip].nnode = nnode;
+ path[h].ptr.nnode = nnode;
+ path[h].in_tree = 1;
+ path[h + 1].cnode.parent = nnode;
+ }
+ if (path[h].in_tree)
+ ubifs_ensure_cat(c, lprops);
+ else {
+ const size_t sz = sizeof(struct ubifs_pnode);
+ struct ubifs_nnode *parent;
+
+ pnode = kmalloc(sz, GFP_NOFS);
+ if (!pnode) {
+ err = -ENOMEM;
+ goto out;
+ }
+ memcpy(pnode, &path[h].pnode, sz);
+ parent = pnode->parent;
+ parent->nbranch[pnode->iip].pnode = pnode;
+ path[h].ptr.pnode = pnode;
+ path[h].in_tree = 1;
+ update_cats(c, pnode);
+ c->pnodes_have += 1;
+ }
+ err = dbg_check_lpt_nodes(c, (struct ubifs_cnode *)
+ c->nroot, 0, 0);
+ if (err)
+ goto out;
+ err = dbg_check_cats(c);
+ if (err)
+ goto out;
+ }
+ if (ret & LPT_SCAN_STOP) {
+ err = 0;
+ break;
+ }
+ /* Get the next lprops */
+ if (lnum == end_lnum) {
+ /*
+ * We got to the end without finding what we were
+ * looking for
+ */
+ err = -ENOSPC;
+ goto out;
+ }
+ if (lnum + 1 >= c->leb_cnt) {
+ /* Wrap-around to the beginning */
+ start_lnum = c->main_first;
+ goto again;
+ }
+ if (iip + 1 < UBIFS_LPT_FANOUT) {
+ /* Next lprops is in the same pnode */
+ iip += 1;
+ continue;
+ }
+ /* We need to get the next pnode. Go up until we can go right */
+ iip = pnode->iip;
+ while (1) {
+ h -= 1;
+ ubifs_assert(h >= 0);
+ nnode = path[h].ptr.nnode;
+ if (iip + 1 < UBIFS_LPT_FANOUT)
+ break;
+ iip = nnode->iip;
+ }
+ /* Go right */
+ iip += 1;
+ /* Descend to the pnode */
+ h += 1;
+ for (; h < c->lpt_hght; h++) {
+ nnode = scan_get_nnode(c, path + h, nnode, iip);
+ if (IS_ERR(nnode)) {
+ err = PTR_ERR(nnode);
+ goto out;
+ }
+ iip = 0;
+ }
+ pnode = scan_get_pnode(c, path + h, nnode, iip);
+ if (IS_ERR(pnode)) {
+ err = PTR_ERR(pnode);
+ goto out;
+ }
+ iip = 0;
+ }
+out:
+ kfree(path);
+ return err;
+}
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+
+/**
+ * dbg_chk_pnode - check a pnode.
+ * @c: the UBIFS file-system description object
+ * @pnode: pnode to check
+ * @col: pnode column
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int dbg_chk_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
+ int col)
+{
+ int i;
+
+ if (pnode->num != col) {
+ dbg_err("pnode num %d expected %d parent num %d iip %d",
+ pnode->num, col, pnode->parent->num, pnode->iip);
+ return -EINVAL;
+ }
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ struct ubifs_lprops *lp, *lprops = &pnode->lprops[i];
+ int lnum = (pnode->num << UBIFS_LPT_FANOUT_SHIFT) + i +
+ c->main_first;
+ int found, cat = lprops->flags & LPROPS_CAT_MASK;
+ struct ubifs_lpt_heap *heap;
+ struct list_head *list = NULL;
+
+ if (lnum >= c->leb_cnt)
+ continue;
+ if (lprops->lnum != lnum) {
+ dbg_err("bad LEB number %d expected %d",
+ lprops->lnum, lnum);
+ return -EINVAL;
+ }
+ if (lprops->flags & LPROPS_TAKEN) {
+ if (cat != LPROPS_UNCAT) {
+ dbg_err("LEB %d taken but not uncat %d",
+ lprops->lnum, cat);
+ return -EINVAL;
+ }
+ continue;
+ }
+ if (lprops->flags & LPROPS_INDEX) {
+ switch (cat) {
+ case LPROPS_UNCAT:
+ case LPROPS_DIRTY_IDX:
+ case LPROPS_FRDI_IDX:
+ break;
+ default:
+ dbg_err("LEB %d index but cat %d",
+ lprops->lnum, cat);
+ return -EINVAL;
+ }
+ } else {
+ switch (cat) {
+ case LPROPS_UNCAT:
+ case LPROPS_DIRTY:
+ case LPROPS_FREE:
+ case LPROPS_EMPTY:
+ case LPROPS_FREEABLE:
+ break;
+ default:
+ dbg_err("LEB %d not index but cat %d",
+ lprops->lnum, cat);
+ return -EINVAL;
+ }
+ }
+ switch (cat) {
+ case LPROPS_UNCAT:
+ list = &c->uncat_list;
+ break;
+ case LPROPS_EMPTY:
+ list = &c->empty_list;
+ break;
+ case LPROPS_FREEABLE:
+ list = &c->freeable_list;
+ break;
+ case LPROPS_FRDI_IDX:
+ list = &c->frdi_idx_list;
+ break;
+ }
+ found = 0;
+ switch (cat) {
+ case LPROPS_DIRTY:
+ case LPROPS_DIRTY_IDX:
+ case LPROPS_FREE:
+ heap = &c->lpt_heap[cat - 1];
+ if (lprops->hpos < heap->cnt &&
+ heap->arr[lprops->hpos] == lprops)
+ found = 1;
+ break;
+ case LPROPS_UNCAT:
+ case LPROPS_EMPTY:
+ case LPROPS_FREEABLE:
+ case LPROPS_FRDI_IDX:
+ list_for_each_entry(lp, list, list)
+ if (lprops == lp) {
+ found = 1;
+ break;
+ }
+ break;
+ }
+ if (!found) {
+ dbg_err("LEB %d cat %d not found in cat heap/list",
+ lprops->lnum, cat);
+ return -EINVAL;
+ }
+ switch (cat) {
+ case LPROPS_EMPTY:
+ if (lprops->free != c->leb_size) {
+ dbg_err("LEB %d cat %d free %d dirty %d",
+ lprops->lnum, cat, lprops->free,
+ lprops->dirty);
+ return -EINVAL;
+ }
+ case LPROPS_FREEABLE:
+ case LPROPS_FRDI_IDX:
+ if (lprops->free + lprops->dirty != c->leb_size) {
+ dbg_err("LEB %d cat %d free %d dirty %d",
+ lprops->lnum, cat, lprops->free,
+ lprops->dirty);
+ return -EINVAL;
+ }
+ }
+ }
+ return 0;
+}
+
+/**
+ * dbg_check_lpt_nodes - check nnodes and pnodes.
+ * @c: the UBIFS file-system description object
+ * @cnode: next cnode (nnode or pnode) to check
+ * @row: row of cnode (root is zero)
+ * @col: column of cnode (leftmost is zero)
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int dbg_check_lpt_nodes(struct ubifs_info *c, struct ubifs_cnode *cnode,
+ int row, int col)
+{
+ struct ubifs_nnode *nnode, *nn;
+ struct ubifs_cnode *cn;
+ int num, iip = 0, err;
+
+ if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS))
+ return 0;
+
+ while (cnode) {
+ ubifs_assert(row >= 0);
+ nnode = cnode->parent;
+ if (cnode->level) {
+ /* cnode is a nnode */
+ num = calc_nnode_num(row, col);
+ if (cnode->num != num) {
+ dbg_err("nnode num %d expected %d "
+ "parent num %d iip %d", cnode->num, num,
+ (nnode ? nnode->num : 0), cnode->iip);
+ return -EINVAL;
+ }
+ nn = (struct ubifs_nnode *)cnode;
+ while (iip < UBIFS_LPT_FANOUT) {
+ cn = nn->nbranch[iip].cnode;
+ if (cn) {
+ /* Go down */
+ row += 1;
+ col <<= UBIFS_LPT_FANOUT_SHIFT;
+ col += iip;
+ iip = 0;
+ cnode = cn;
+ break;
+ }
+ /* Go right */
+ iip += 1;
+ }
+ if (iip < UBIFS_LPT_FANOUT)
+ continue;
+ } else {
+ struct ubifs_pnode *pnode;
+
+ /* cnode is a pnode */
+ pnode = (struct ubifs_pnode *)cnode;
+ err = dbg_chk_pnode(c, pnode, col);
+ if (err)
+ return err;
+ }
+ /* Go up and to the right */
+ row -= 1;
+ col >>= UBIFS_LPT_FANOUT_SHIFT;
+ iip = cnode->iip + 1;
+ cnode = (struct ubifs_cnode *)nnode;
+ }
+ return 0;
+}
+
+#endif /* CONFIG_UBIFS_FS_DEBUG */
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ * Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file implements commit-related functionality of the LEB properties
+ * subsystem.
+ */
+
+#include <linux/crc16.h>
+#include "ubifs.h"
+
+/**
+ * first_dirty_cnode - find first dirty cnode.
+ * @c: UBIFS file-system description object
+ * @nnode: nnode at which to start
+ *
+ * This function returns the first dirty cnode or %NULL if there is not one.
+ */
+static struct ubifs_cnode *first_dirty_cnode(struct ubifs_nnode *nnode)
+{
+ ubifs_assert(nnode);
+ while (1) {
+ int i, cont = 0;
+
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ struct ubifs_cnode *cnode;
+
+ cnode = nnode->nbranch[i].cnode;
+ if (cnode &&
+ test_bit(DIRTY_CNODE, &cnode->flags)) {
+ if (cnode->level == 0)
+ return cnode;
+ nnode = (struct ubifs_nnode *)cnode;
+ cont = 1;
+ break;
+ }
+ }
+ if (!cont)
+ return (struct ubifs_cnode *)nnode;
+ }
+}
+
+/**
+ * next_dirty_cnode - find next dirty cnode.
+ * @cnode: cnode from which to begin searching
+ *
+ * This function returns the next dirty cnode or %NULL if there is not one.
+ */
+static struct ubifs_cnode *next_dirty_cnode(struct ubifs_cnode *cnode)
+{
+ struct ubifs_nnode *nnode;
+ int i;
+
+ ubifs_assert(cnode);
+ nnode = cnode->parent;
+ if (!nnode)
+ return NULL;
+ for (i = cnode->iip + 1; i < UBIFS_LPT_FANOUT; i++) {
+ cnode = nnode->nbranch[i].cnode;
+ if (cnode && test_bit(DIRTY_CNODE, &cnode->flags)) {
+ if (cnode->level == 0)
+ return cnode; /* cnode is a pnode */
+ /* cnode is a nnode */
+ return first_dirty_cnode((struct ubifs_nnode *)cnode);
+ }
+ }
+ return (struct ubifs_cnode *)nnode;
+}
+
+/**
+ * get_cnodes_to_commit - create list of dirty cnodes to commit.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns the number of cnodes to commit.
+ */
+static int get_cnodes_to_commit(struct ubifs_info *c)
+{
+ struct ubifs_cnode *cnode, *cnext;
+ int cnt = 0;
+
+ if (!c->nroot)
+ return 0;
+
+ if (!test_bit(DIRTY_CNODE, &c->nroot->flags))
+ return 0;
+
+ c->lpt_cnext = first_dirty_cnode(c->nroot);
+ cnode = c->lpt_cnext;
+ if (!cnode)
+ return 0;
+ cnt += 1;
+ while (1) {
+ ubifs_assert(!test_bit(COW_ZNODE, &cnode->flags));
+ __set_bit(COW_ZNODE, &cnode->flags);
+ cnext = next_dirty_cnode(cnode);
+ if (!cnext) {
+ cnode->cnext = c->lpt_cnext;
+ break;
+ }
+ cnode->cnext = cnext;
+ cnode = cnext;
+ cnt += 1;
+ }
+ dbg_cmt("committing %d cnodes", cnt);
+ dbg_lp("committing %d cnodes", cnt);
+ ubifs_assert(cnt == c->dirty_nn_cnt + c->dirty_pn_cnt);
+ return cnt;
+}
+
+/**
+ * upd_ltab - update LPT LEB properties.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number
+ * @free: amount of free space
+ * @dirty: amount of dirty space to add
+ */
+static void upd_ltab(struct ubifs_info *c, int lnum, int free, int dirty)
+{
+ dbg_lp("LEB %d free %d dirty %d to %d +%d",
+ lnum, c->ltab[lnum - c->lpt_first].free,
+ c->ltab[lnum - c->lpt_first].dirty, free, dirty);
+ ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last);
+ c->ltab[lnum - c->lpt_first].free = free;
+ c->ltab[lnum - c->lpt_first].dirty += dirty;
+}
+
+/**
+ * alloc_lpt_leb - allocate an LPT LEB that is empty.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number is passed and returned here
+ *
+ * This function finds the next empty LEB in the ltab starting from @lnum. If a
+ * an empty LEB is found it is returned in @lnum and the function returns %0.
+ * Otherwise the function returns -ENOSPC. Note however, that LPT is designed
+ * never to run out of space.
+ */
+static int alloc_lpt_leb(struct ubifs_info *c, int *lnum)
+{
+ int i, n;
+
+ n = *lnum - c->lpt_first + 1;
+ for (i = n; i < c->lpt_lebs; i++) {
+ if (c->ltab[i].tgc || c->ltab[i].cmt)
+ continue;
+ if (c->ltab[i].free == c->leb_size) {
+ c->ltab[i].cmt = 1;
+ *lnum = i + c->lpt_first;
+ return 0;
+ }
+ }
+
+ for (i = 0; i < n; i++) {
+ if (c->ltab[i].tgc || c->ltab[i].cmt)
+ continue;
+ if (c->ltab[i].free == c->leb_size) {
+ c->ltab[i].cmt = 1;
+ *lnum = i + c->lpt_first;
+ return 0;
+ }
+ }
+ dbg_err("last LEB %d", *lnum);
+ dump_stack();
+ return -ENOSPC;
+}
+
+/**
+ * layout_cnodes - layout cnodes for commit.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int layout_cnodes(struct ubifs_info *c)
+{
+ int lnum, offs, len, alen, done_lsave, done_ltab, err;
+ struct ubifs_cnode *cnode;
+
+ cnode = c->lpt_cnext;
+ if (!cnode)
+ return 0;
+ lnum = c->nhead_lnum;
+ offs = c->nhead_offs;
+ /* Try to place lsave and ltab nicely */
+ done_lsave = !c->big_lpt;
+ done_ltab = 0;
+ if (!done_lsave && offs + c->lsave_sz <= c->leb_size) {
+ done_lsave = 1;
+ c->lsave_lnum = lnum;
+ c->lsave_offs = offs;
+ offs += c->lsave_sz;
+ }
+
+ if (offs + c->ltab_sz <= c->leb_size) {
+ done_ltab = 1;
+ c->ltab_lnum = lnum;
+ c->ltab_offs = offs;
+ offs += c->ltab_sz;
+ }
+
+ do {
+ if (cnode->level) {
+ len = c->nnode_sz;
+ c->dirty_nn_cnt -= 1;
+ } else {
+ len = c->pnode_sz;
+ c->dirty_pn_cnt -= 1;
+ }
+ while (offs + len > c->leb_size) {
+ alen = ALIGN(offs, c->min_io_size);
+ upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
+ err = alloc_lpt_leb(c, &lnum);
+ if (err)
+ return err;
+ offs = 0;
+ ubifs_assert(lnum >= c->lpt_first &&
+ lnum <= c->lpt_last);
+ /* Try to place lsave and ltab nicely */
+ if (!done_lsave) {
+ done_lsave = 1;
+ c->lsave_lnum = lnum;
+ c->lsave_offs = offs;
+ offs += c->lsave_sz;
+ continue;
+ }
+ if (!done_ltab) {
+ done_ltab = 1;
+ c->ltab_lnum = lnum;
+ c->ltab_offs = offs;
+ offs += c->ltab_sz;
+ continue;
+ }
+ break;
+ }
+ if (cnode->parent) {
+ cnode->parent->nbranch[cnode->iip].lnum = lnum;
+ cnode->parent->nbranch[cnode->iip].offs = offs;
+ } else {
+ c->lpt_lnum = lnum;
+ c->lpt_offs = offs;
+ }
+ offs += len;
+ cnode = cnode->cnext;
+ } while (cnode && cnode != c->lpt_cnext);
+
+ /* Make sure to place LPT's save table */
+ if (!done_lsave) {
+ if (offs + c->lsave_sz > c->leb_size) {
+ alen = ALIGN(offs, c->min_io_size);
+ upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
+ err = alloc_lpt_leb(c, &lnum);
+ if (err)
+ return err;
+ offs = 0;
+ ubifs_assert(lnum >= c->lpt_first &&
+ lnum <= c->lpt_last);
+ }
+ done_lsave = 1;
+ c->lsave_lnum = lnum;
+ c->lsave_offs = offs;
+ offs += c->lsave_sz;
+ }
+
+ /* Make sure to place LPT's own lprops table */
+ if (!done_ltab) {
+ if (offs + c->ltab_sz > c->leb_size) {
+ alen = ALIGN(offs, c->min_io_size);
+ upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
+ err = alloc_lpt_leb(c, &lnum);
+ if (err)
+ return err;
+ offs = 0;
+ ubifs_assert(lnum >= c->lpt_first &&
+ lnum <= c->lpt_last);
+ }
+ done_ltab = 1;
+ c->ltab_lnum = lnum;
+ c->ltab_offs = offs;
+ offs += c->ltab_sz;
+ }
+
+ alen = ALIGN(offs, c->min_io_size);
+ upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
+ return 0;
+}
+
+/**
+ * realloc_lpt_leb - allocate an LPT LEB that is empty.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number is passed and returned here
+ *
+ * This function duplicates exactly the results of the function alloc_lpt_leb.
+ * It is used during end commit to reallocate the same LEB numbers that were
+ * allocated by alloc_lpt_leb during start commit.
+ *
+ * This function finds the next LEB that was allocated by the alloc_lpt_leb
+ * function starting from @lnum. If a LEB is found it is returned in @lnum and
+ * the function returns %0. Otherwise the function returns -ENOSPC.
+ * Note however, that LPT is designed never to run out of space.
+ */
+static int realloc_lpt_leb(struct ubifs_info *c, int *lnum)
+{
+ int i, n;
+
+ n = *lnum - c->lpt_first + 1;
+ for (i = n; i < c->lpt_lebs; i++)
+ if (c->ltab[i].cmt) {
+ c->ltab[i].cmt = 0;
+ *lnum = i + c->lpt_first;
+ return 0;
+ }
+
+ for (i = 0; i < n; i++)
+ if (c->ltab[i].cmt) {
+ c->ltab[i].cmt = 0;
+ *lnum = i + c->lpt_first;
+ return 0;
+ }
+ dbg_err("last LEB %d", *lnum);
+ dump_stack();
+ return -ENOSPC;
+}
+
+/**
+ * write_cnodes - write cnodes for commit.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int write_cnodes(struct ubifs_info *c)
+{
+ int lnum, offs, len, from, err, wlen, alen, done_ltab, done_lsave;
+ struct ubifs_cnode *cnode;
+ void *buf = c->lpt_buf;
+
+ cnode = c->lpt_cnext;
+ if (!cnode)
+ return 0;
+ lnum = c->nhead_lnum;
+ offs = c->nhead_offs;
+ from = offs;
+ /* Ensure empty LEB is unmapped */
+ if (offs == 0) {
+ err = ubifs_leb_unmap(c, lnum);
+ if (err)
+ return err;
+ }
+ /* Try to place lsave and ltab nicely */
+ done_lsave = !c->big_lpt;
+ done_ltab = 0;
+ if (!done_lsave && offs + c->lsave_sz <= c->leb_size) {
+ done_lsave = 1;
+ ubifs_pack_lsave(c, buf + offs, c->lsave);
+ offs += c->lsave_sz;
+ }
+
+ if (offs + c->ltab_sz <= c->leb_size) {
+ done_ltab = 1;
+ ubifs_pack_ltab(c, buf + offs, c->ltab_cmt);
+ offs += c->ltab_sz;
+ }
+
+ /* Loop for each cnode */
+ do {
+ if (cnode->level)
+ len = c->nnode_sz;
+ else
+ len = c->pnode_sz;
+ while (offs + len > c->leb_size) {
+ wlen = offs - from;
+ if (wlen) {
+ alen = ALIGN(wlen, c->min_io_size);
+ memset(buf + offs, 0xff, alen - wlen);
+ err = ubifs_leb_write(c, lnum, buf + from, from,
+ alen, UBI_SHORTTERM);
+ if (err)
+ return err;
+ }
+ err = realloc_lpt_leb(c, &lnum);
+ if (err)
+ return err;
+ offs = 0;
+ from = 0;
+ ubifs_assert(lnum >= c->lpt_first &&
+ lnum <= c->lpt_last);
+ err = ubifs_leb_unmap(c, lnum);
+ if (err)
+ return err;
+ /* Try to place lsave and ltab nicely */
+ if (!done_lsave) {
+ done_lsave = 1;
+ ubifs_pack_lsave(c, buf + offs, c->lsave);
+ offs += c->lsave_sz;
+ continue;
+ }
+ if (!done_ltab) {
+ done_ltab = 1;
+ ubifs_pack_ltab(c, buf + offs, c->ltab_cmt);
+ offs += c->ltab_sz;
+ continue;
+ }
+ break;
+ }
+ if (cnode->level)
+ ubifs_pack_nnode(c, buf + offs,
+ (struct ubifs_nnode *)cnode);
+ else
+ ubifs_pack_pnode(c, buf + offs,
+ (struct ubifs_pnode *)cnode);
+ /*
+ * The reason for the barriers is the same as in case of TNC.
+ * See comment in 'write_index()'. 'dirty_cow_nnode()' and
+ * 'dirty_cow_pnode()' are the functions for which this is
+ * important.
+ */
+ clear_bit(DIRTY_CNODE, &cnode->flags);
+ smp_mb__before_clear_bit();
+ clear_bit(COW_ZNODE, &cnode->flags);
+ smp_mb__after_clear_bit();
+ offs += len;
+ cnode = cnode->cnext;
+ } while (cnode && cnode != c->lpt_cnext);
+
+ /* Make sure to place LPT's save table */
+ if (!done_lsave) {
+ if (offs + c->lsave_sz > c->leb_size) {
+ wlen = offs - from;
+ alen = ALIGN(wlen, c->min_io_size);
+ memset(buf + offs, 0xff, alen - wlen);
+ err = ubifs_leb_write(c, lnum, buf + from, from, alen,
+ UBI_SHORTTERM);
+ if (err)
+ return err;
+ err = realloc_lpt_leb(c, &lnum);
+ if (err)
+ return err;
+ offs = 0;
+ ubifs_assert(lnum >= c->lpt_first &&
+ lnum <= c->lpt_last);
+ err = ubifs_leb_unmap(c, lnum);
+ if (err)
+ return err;
+ }
+ done_lsave = 1;
+ ubifs_pack_lsave(c, buf + offs, c->lsave);
+ offs += c->lsave_sz;
+ }
+
+ /* Make sure to place LPT's own lprops table */
+ if (!done_ltab) {
+ if (offs + c->ltab_sz > c->leb_size) {
+ wlen = offs - from;
+ alen = ALIGN(wlen, c->min_io_size);
+ memset(buf + offs, 0xff, alen - wlen);
+ err = ubifs_leb_write(c, lnum, buf + from, from, alen,
+ UBI_SHORTTERM);
+ if (err)
+ return err;
+ err = realloc_lpt_leb(c, &lnum);
+ if (err)
+ return err;
+ offs = 0;
+ ubifs_assert(lnum >= c->lpt_first &&
+ lnum <= c->lpt_last);
+ err = ubifs_leb_unmap(c, lnum);
+ if (err)
+ return err;
+ }
+ done_ltab = 1;
+ ubifs_pack_ltab(c, buf + offs, c->ltab_cmt);
+ offs += c->ltab_sz;
+ }
+
+ /* Write remaining data in buffer */
+ wlen = offs - from;
+ alen = ALIGN(wlen, c->min_io_size);
+ memset(buf + offs, 0xff, alen - wlen);
+ err = ubifs_leb_write(c, lnum, buf + from, from, alen, UBI_SHORTTERM);
+ if (err)
+ return err;
+ c->nhead_lnum = lnum;
+ c->nhead_offs = ALIGN(offs, c->min_io_size);
+
+ dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs);
+ dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs);
+ dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs);
+ if (c->big_lpt)
+ dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs);
+ return 0;
+}
+
+/**
+ * next_pnode - find next pnode.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode
+ *
+ * This function returns the next pnode or %NULL if there are no more pnodes.
+ */
+static struct ubifs_pnode *next_pnode(struct ubifs_info *c,
+ struct ubifs_pnode *pnode)
+{
+ struct ubifs_nnode *nnode;
+ int iip;
+
+ /* Try to go right */
+ nnode = pnode->parent;
+ iip = pnode->iip + 1;
+ if (iip < UBIFS_LPT_FANOUT) {
+ /* We assume here that LEB zero is never an LPT LEB */
+ if (nnode->nbranch[iip].lnum)
+ return ubifs_get_pnode(c, nnode, iip);
+ else
+ return NULL;
+ }
+
+ /* Go up while can't go right */
+ do {
+ iip = nnode->iip + 1;
+ nnode = nnode->parent;
+ if (!nnode)
+ return NULL;
+ /* We assume here that LEB zero is never an LPT LEB */
+ } while (iip >= UBIFS_LPT_FANOUT || !nnode->nbranch[iip].lnum);
+
+ /* Go right */
+ nnode = ubifs_get_nnode(c, nnode, iip);
+ if (IS_ERR(nnode))
+ return (void *)nnode;
+
+ /* Go down to level 1 */
+ while (nnode->level > 1) {
+ nnode = ubifs_get_nnode(c, nnode, 0);
+ if (IS_ERR(nnode))
+ return (void *)nnode;
+ }
+
+ return ubifs_get_pnode(c, nnode, 0);
+}
+
+/**
+ * pnode_lookup - lookup a pnode in the LPT.
+ * @c: UBIFS file-system description object
+ * @i: pnode number (0 to main_lebs - 1)
+ *
+ * This function returns a pointer to the pnode on success or a negative
+ * error code on failure.
+ */
+static struct ubifs_pnode *pnode_lookup(struct ubifs_info *c, int i)
+{
+ int err, h, iip, shft;
+ struct ubifs_nnode *nnode;
+
+ if (!c->nroot) {
+ err = ubifs_read_nnode(c, NULL, 0);
+ if (err)
+ return ERR_PTR(err);
+ }
+ i <<= UBIFS_LPT_FANOUT_SHIFT;
+ nnode = c->nroot;
+ shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
+ for (h = 1; h < c->lpt_hght; h++) {
+ iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
+ shft -= UBIFS_LPT_FANOUT_SHIFT;
+ nnode = ubifs_get_nnode(c, nnode, iip);
+ if (IS_ERR(nnode))
+ return ERR_PTR(PTR_ERR(nnode));
+ }
+ iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
+ return ubifs_get_pnode(c, nnode, iip);
+}
+
+/**
+ * add_pnode_dirt - add dirty space to LPT LEB properties.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode for which to add dirt
+ */
+static void add_pnode_dirt(struct ubifs_info *c, struct ubifs_pnode *pnode)
+{
+ ubifs_add_lpt_dirt(c, pnode->parent->nbranch[pnode->iip].lnum,
+ c->pnode_sz);
+}
+
+/**
+ * do_make_pnode_dirty - mark a pnode dirty.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode to mark dirty
+ */
+static void do_make_pnode_dirty(struct ubifs_info *c, struct ubifs_pnode *pnode)
+{
+ /* Assumes cnext list is empty i.e. not called during commit */
+ if (!test_and_set_bit(DIRTY_CNODE, &pnode->flags)) {
+ struct ubifs_nnode *nnode;
+
+ c->dirty_pn_cnt += 1;
+ add_pnode_dirt(c, pnode);
+ /* Mark parent and ancestors dirty too */
+ nnode = pnode->parent;
+ while (nnode) {
+ if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
+ c->dirty_nn_cnt += 1;
+ ubifs_add_nnode_dirt(c, nnode);
+ nnode = nnode->parent;
+ } else
+ break;
+ }
+ }
+}
+
+/**
+ * make_tree_dirty - mark the entire LEB properties tree dirty.
+ * @c: UBIFS file-system description object
+ *
+ * This function is used by the "small" LPT model to cause the entire LEB
+ * properties tree to be written. The "small" LPT model does not use LPT
+ * garbage collection because it is more efficient to write the entire tree
+ * (because it is small).
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int make_tree_dirty(struct ubifs_info *c)
+{
+ struct ubifs_pnode *pnode;
+
+ pnode = pnode_lookup(c, 0);
+ while (pnode) {
+ do_make_pnode_dirty(c, pnode);
+ pnode = next_pnode(c, pnode);
+ if (IS_ERR(pnode))
+ return PTR_ERR(pnode);
+ }
+ return 0;
+}
+
+/**
+ * need_write_all - determine if the LPT area is running out of free space.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns %1 if the LPT area is running out of free space and %0
+ * if it is not.
+ */
+static int need_write_all(struct ubifs_info *c)
+{
+ long long free = 0;
+ int i;
+
+ for (i = 0; i < c->lpt_lebs; i++) {
+ if (i + c->lpt_first == c->nhead_lnum)
+ free += c->leb_size - c->nhead_offs;
+ else if (c->ltab[i].free == c->leb_size)
+ free += c->leb_size;
+ else if (c->ltab[i].free + c->ltab[i].dirty == c->leb_size)
+ free += c->leb_size;
+ }
+ /* Less than twice the size left */
+ if (free <= c->lpt_sz * 2)
+ return 1;
+ return 0;
+}
+
+/**
+ * lpt_tgc_start - start trivial garbage collection of LPT LEBs.
+ * @c: UBIFS file-system description object
+ *
+ * LPT trivial garbage collection is where a LPT LEB contains only dirty and
+ * free space and so may be reused as soon as the next commit is completed.
+ * This function is called during start commit to mark LPT LEBs for trivial GC.
+ */
+static void lpt_tgc_start(struct ubifs_info *c)
+{
+ int i;
+
+ for (i = 0; i < c->lpt_lebs; i++) {
+ if (i + c->lpt_first == c->nhead_lnum)
+ continue;
+ if (c->ltab[i].dirty > 0 &&
+ c->ltab[i].free + c->ltab[i].dirty == c->leb_size) {
+ c->ltab[i].tgc = 1;
+ c->ltab[i].free = c->leb_size;
+ c->ltab[i].dirty = 0;
+ dbg_lp("LEB %d", i + c->lpt_first);
+ }
+ }
+}
+
+/**
+ * lpt_tgc_end - end trivial garbage collection of LPT LEBs.
+ * @c: UBIFS file-system description object
+ *
+ * LPT trivial garbage collection is where a LPT LEB contains only dirty and
+ * free space and so may be reused as soon as the next commit is completed.
+ * This function is called after the commit is completed (master node has been
+ * written) and unmaps LPT LEBs that were marked for trivial GC.
+ */
+static int lpt_tgc_end(struct ubifs_info *c)
+{
+ int i, err;
+
+ for (i = 0; i < c->lpt_lebs; i++)
+ if (c->ltab[i].tgc) {
+ err = ubifs_leb_unmap(c, i + c->lpt_first);
+ if (err)
+ return err;
+ c->ltab[i].tgc = 0;
+ dbg_lp("LEB %d", i + c->lpt_first);
+ }
+ return 0;
+}
+
+/**
+ * populate_lsave - fill the lsave array with important LEB numbers.
+ * @c: the UBIFS file-system description object
+ *
+ * This function is only called for the "big" model. It records a small number
+ * of LEB numbers of important LEBs. Important LEBs are ones that are (from
+ * most important to least important): empty, freeable, freeable index, dirty
+ * index, dirty or free. Upon mount, we read this list of LEB numbers and bring
+ * their pnodes into memory. That will stop us from having to scan the LPT
+ * straight away. For the "small" model we assume that scanning the LPT is no
+ * big deal.
+ */
+static void populate_lsave(struct ubifs_info *c)
+{
+ struct ubifs_lprops *lprops;
+ struct ubifs_lpt_heap *heap;
+ int i, cnt = 0;
+
+ ubifs_assert(c->big_lpt);
+ if (!(c->lpt_drty_flgs & LSAVE_DIRTY)) {
+ c->lpt_drty_flgs |= LSAVE_DIRTY;
+ ubifs_add_lpt_dirt(c, c->lsave_lnum, c->lsave_sz);
+ }
+ list_for_each_entry(lprops, &c->empty_list, list) {
+ c->lsave[cnt++] = lprops->lnum;
+ if (cnt >= c->lsave_cnt)
+ return;
+ }
+ list_for_each_entry(lprops, &c->freeable_list, list) {
+ c->lsave[cnt++] = lprops->lnum;
+ if (cnt >= c->lsave_cnt)
+ return;
+ }
+ list_for_each_entry(lprops, &c->frdi_idx_list, list) {
+ c->lsave[cnt++] = lprops->lnum;
+ if (cnt >= c->lsave_cnt)
+ return;
+ }
+ heap = &c->lpt_heap[LPROPS_DIRTY_IDX - 1];
+ for (i = 0; i < heap->cnt; i++) {
+ c->lsave[cnt++] = heap->arr[i]->lnum;
+ if (cnt >= c->lsave_cnt)
+ return;
+ }
+ heap = &c->lpt_heap[LPROPS_DIRTY - 1];
+ for (i = 0; i < heap->cnt; i++) {
+ c->lsave[cnt++] = heap->arr[i]->lnum;
+ if (cnt >= c->lsave_cnt)
+ return;
+ }
+ heap = &c->lpt_heap[LPROPS_FREE - 1];
+ for (i = 0; i < heap->cnt; i++) {
+ c->lsave[cnt++] = heap->arr[i]->lnum;
+ if (cnt >= c->lsave_cnt)
+ return;
+ }
+ /* Fill it up completely */
+ while (cnt < c->lsave_cnt)
+ c->lsave[cnt++] = c->main_first;
+}
+
+/**
+ * nnode_lookup - lookup a nnode in the LPT.
+ * @c: UBIFS file-system description object
+ * @i: nnode number
+ *
+ * This function returns a pointer to the nnode on success or a negative
+ * error code on failure.
+ */
+static struct ubifs_nnode *nnode_lookup(struct ubifs_info *c, int i)
+{
+ int err, iip;
+ struct ubifs_nnode *nnode;
+
+ if (!c->nroot) {
+ err = ubifs_read_nnode(c, NULL, 0);
+ if (err)
+ return ERR_PTR(err);
+ }
+ nnode = c->nroot;
+ while (1) {
+ iip = i & (UBIFS_LPT_FANOUT - 1);
+ i >>= UBIFS_LPT_FANOUT_SHIFT;
+ if (!i)
+ break;
+ nnode = ubifs_get_nnode(c, nnode, iip);
+ if (IS_ERR(nnode))
+ return nnode;
+ }
+ return nnode;
+}
+
+/**
+ * make_nnode_dirty - find a nnode and, if found, make it dirty.
+ * @c: UBIFS file-system description object
+ * @node_num: nnode number of nnode to make dirty
+ * @lnum: LEB number where nnode was written
+ * @offs: offset where nnode was written
+ *
+ * This function is used by LPT garbage collection. LPT garbage collection is
+ * used only for the "big" LPT model (c->big_lpt == 1). Garbage collection
+ * simply involves marking all the nodes in the LEB being garbage-collected as
+ * dirty. The dirty nodes are written next commit, after which the LEB is free
+ * to be reused.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int make_nnode_dirty(struct ubifs_info *c, int node_num, int lnum,
+ int offs)
+{
+ struct ubifs_nnode *nnode;
+
+ nnode = nnode_lookup(c, node_num);
+ if (IS_ERR(nnode))
+ return PTR_ERR(nnode);
+ if (nnode->parent) {
+ struct ubifs_nbranch *branch;
+
+ branch = &nnode->parent->nbranch[nnode->iip];
+ if (branch->lnum != lnum || branch->offs != offs)
+ return 0; /* nnode is obsolete */
+ } else if (c->lpt_lnum != lnum || c->lpt_offs != offs)
+ return 0; /* nnode is obsolete */
+ /* Assumes cnext list is empty i.e. not called during commit */
+ if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
+ c->dirty_nn_cnt += 1;
+ ubifs_add_nnode_dirt(c, nnode);
+ /* Mark parent and ancestors dirty too */
+ nnode = nnode->parent;
+ while (nnode) {
+ if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
+ c->dirty_nn_cnt += 1;
+ ubifs_add_nnode_dirt(c, nnode);
+ nnode = nnode->parent;
+ } else
+ break;
+ }
+ }
+ return 0;
+}
+
+/**
+ * make_pnode_dirty - find a pnode and, if found, make it dirty.
+ * @c: UBIFS file-system description object
+ * @node_num: pnode number of pnode to make dirty
+ * @lnum: LEB number where pnode was written
+ * @offs: offset where pnode was written
+ *
+ * This function is used by LPT garbage collection. LPT garbage collection is
+ * used only for the "big" LPT model (c->big_lpt == 1). Garbage collection
+ * simply involves marking all the nodes in the LEB being garbage-collected as
+ * dirty. The dirty nodes are written next commit, after which the LEB is free
+ * to be reused.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int make_pnode_dirty(struct ubifs_info *c, int node_num, int lnum,
+ int offs)
+{
+ struct ubifs_pnode *pnode;
+ struct ubifs_nbranch *branch;
+
+ pnode = pnode_lookup(c, node_num);
+ if (IS_ERR(pnode))
+ return PTR_ERR(pnode);
+ branch = &pnode->parent->nbranch[pnode->iip];
+ if (branch->lnum != lnum || branch->offs != offs)
+ return 0;
+ do_make_pnode_dirty(c, pnode);
+ return 0;
+}
+
+/**
+ * make_ltab_dirty - make ltab node dirty.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number where ltab was written
+ * @offs: offset where ltab was written
+ *
+ * This function is used by LPT garbage collection. LPT garbage collection is
+ * used only for the "big" LPT model (c->big_lpt == 1). Garbage collection
+ * simply involves marking all the nodes in the LEB being garbage-collected as
+ * dirty. The dirty nodes are written next commit, after which the LEB is free
+ * to be reused.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int make_ltab_dirty(struct ubifs_info *c, int lnum, int offs)
+{
+ if (lnum != c->ltab_lnum || offs != c->ltab_offs)
+ return 0; /* This ltab node is obsolete */
+ if (!(c->lpt_drty_flgs & LTAB_DIRTY)) {
+ c->lpt_drty_flgs |= LTAB_DIRTY;
+ ubifs_add_lpt_dirt(c, c->ltab_lnum, c->ltab_sz);
+ }
+ return 0;
+}
+
+/**
+ * make_lsave_dirty - make lsave node dirty.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number where lsave was written
+ * @offs: offset where lsave was written
+ *
+ * This function is used by LPT garbage collection. LPT garbage collection is
+ * used only for the "big" LPT model (c->big_lpt == 1). Garbage collection
+ * simply involves marking all the nodes in the LEB being garbage-collected as
+ * dirty. The dirty nodes are written next commit, after which the LEB is free
+ * to be reused.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int make_lsave_dirty(struct ubifs_info *c, int lnum, int offs)
+{
+ if (lnum != c->lsave_lnum || offs != c->lsave_offs)
+ return 0; /* This lsave node is obsolete */
+ if (!(c->lpt_drty_flgs & LSAVE_DIRTY)) {
+ c->lpt_drty_flgs |= LSAVE_DIRTY;
+ ubifs_add_lpt_dirt(c, c->lsave_lnum, c->lsave_sz);
+ }
+ return 0;
+}
+
+/**
+ * make_node_dirty - make node dirty.
+ * @c: UBIFS file-system description object
+ * @node_type: LPT node type
+ * @node_num: node number
+ * @lnum: LEB number where node was written
+ * @offs: offset where node was written
+ *
+ * This function is used by LPT garbage collection. LPT garbage collection is
+ * used only for the "big" LPT model (c->big_lpt == 1). Garbage collection
+ * simply involves marking all the nodes in the LEB being garbage-collected as
+ * dirty. The dirty nodes are written next commit, after which the LEB is free
+ * to be reused.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int make_node_dirty(struct ubifs_info *c, int node_type, int node_num,
+ int lnum, int offs)
+{
+ switch (node_type) {
+ case UBIFS_LPT_NNODE:
+ return make_nnode_dirty(c, node_num, lnum, offs);
+ case UBIFS_LPT_PNODE:
+ return make_pnode_dirty(c, node_num, lnum, offs);
+ case UBIFS_LPT_LTAB:
+ return make_ltab_dirty(c, lnum, offs);
+ case UBIFS_LPT_LSAVE:
+ return make_lsave_dirty(c, lnum, offs);
+ }
+ return -EINVAL;
+}
+
+/**
+ * get_lpt_node_len - return the length of a node based on its type.
+ * @c: UBIFS file-system description object
+ * @node_type: LPT node type
+ */
+static int get_lpt_node_len(struct ubifs_info *c, int node_type)
+{
+ switch (node_type) {
+ case UBIFS_LPT_NNODE:
+ return c->nnode_sz;
+ case UBIFS_LPT_PNODE:
+ return c->pnode_sz;
+ case UBIFS_LPT_LTAB:
+ return c->ltab_sz;
+ case UBIFS_LPT_LSAVE:
+ return c->lsave_sz;
+ }
+ return 0;
+}
+
+/**
+ * get_pad_len - return the length of padding in a buffer.
+ * @c: UBIFS file-system description object
+ * @buf: buffer
+ * @len: length of buffer
+ */
+static int get_pad_len(struct ubifs_info *c, uint8_t *buf, int len)
+{
+ int offs, pad_len;
+
+ if (c->min_io_size == 1)
+ return 0;
+ offs = c->leb_size - len;
+ pad_len = ALIGN(offs, c->min_io_size) - offs;
+ return pad_len;
+}
+
+/**
+ * get_lpt_node_type - return type (and node number) of a node in a buffer.
+ * @c: UBIFS file-system description object
+ * @buf: buffer
+ * @node_num: node number is returned here
+ */
+static int get_lpt_node_type(struct ubifs_info *c, uint8_t *buf, int *node_num)
+{
+ uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+ int pos = 0, node_type;
+
+ node_type = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_TYPE_BITS);
+ *node_num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits);
+ return node_type;
+}
+
+/**
+ * is_a_node - determine if a buffer contains a node.
+ * @c: UBIFS file-system description object
+ * @buf: buffer
+ * @len: length of buffer
+ *
+ * This function returns %1 if the buffer contains a node or %0 if it does not.
+ */
+static int is_a_node(struct ubifs_info *c, uint8_t *buf, int len)
+{
+ uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+ int pos = 0, node_type, node_len;
+ uint16_t crc, calc_crc;
+
+ node_type = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_TYPE_BITS);
+ if (node_type == UBIFS_LPT_NOT_A_NODE)
+ return 0;
+ node_len = get_lpt_node_len(c, node_type);
+ if (!node_len || node_len > len)
+ return 0;
+ pos = 0;
+ addr = buf;
+ crc = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_CRC_BITS);
+ calc_crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
+ node_len - UBIFS_LPT_CRC_BYTES);
+ if (crc != calc_crc)
+ return 0;
+ return 1;
+}
+
+
+/**
+ * lpt_gc_lnum - garbage collect a LPT LEB.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to garbage collect
+ *
+ * LPT garbage collection is used only for the "big" LPT model
+ * (c->big_lpt == 1). Garbage collection simply involves marking all the nodes
+ * in the LEB being garbage-collected as dirty. The dirty nodes are written
+ * next commit, after which the LEB is free to be reused.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int lpt_gc_lnum(struct ubifs_info *c, int lnum)
+{
+ int err, len = c->leb_size, node_type, node_num, node_len, offs;
+ void *buf = c->lpt_buf;
+
+ dbg_lp("LEB %d", lnum);
+ err = ubi_read(c->ubi, lnum, buf, 0, c->leb_size);
+ if (err) {
+ ubifs_err("cannot read LEB %d, error %d", lnum, err);
+ return err;
+ }
+ while (1) {
+ if (!is_a_node(c, buf, len)) {
+ int pad_len;
+
+ pad_len = get_pad_len(c, buf, len);
+ if (pad_len) {
+ buf += pad_len;
+ len -= pad_len;
+ continue;
+ }
+ return 0;
+ }
+ node_type = get_lpt_node_type(c, buf, &node_num);
+ node_len = get_lpt_node_len(c, node_type);
+ offs = c->leb_size - len;
+ ubifs_assert(node_len != 0);
+ mutex_lock(&c->lp_mutex);
+ err = make_node_dirty(c, node_type, node_num, lnum, offs);
+ mutex_unlock(&c->lp_mutex);
+ if (err)
+ return err;
+ buf += node_len;
+ len -= node_len;
+ }
+ return 0;
+}
+
+/**
+ * lpt_gc - LPT garbage collection.
+ * @c: UBIFS file-system description object
+ *
+ * Select a LPT LEB for LPT garbage collection and call 'lpt_gc_lnum()'.
+ * Returns %0 on success and a negative error code on failure.
+ */
+static int lpt_gc(struct ubifs_info *c)
+{
+ int i, lnum = -1, dirty = 0;
+
+ mutex_lock(&c->lp_mutex);
+ for (i = 0; i < c->lpt_lebs; i++) {
+ ubifs_assert(!c->ltab[i].tgc);
+ if (i + c->lpt_first == c->nhead_lnum ||
+ c->ltab[i].free + c->ltab[i].dirty == c->leb_size)
+ continue;
+ if (c->ltab[i].dirty > dirty) {
+ dirty = c->ltab[i].dirty;
+ lnum = i + c->lpt_first;
+ }
+ }
+ mutex_unlock(&c->lp_mutex);
+ if (lnum == -1)
+ return -ENOSPC;
+ return lpt_gc_lnum(c, lnum);
+}
+
+/**
+ * ubifs_lpt_start_commit - UBIFS commit starts.
+ * @c: the UBIFS file-system description object
+ *
+ * This function has to be called when UBIFS starts the commit operation.
+ * This function "freezes" all currently dirty LEB properties and does not
+ * change them anymore. Further changes are saved and tracked separately
+ * because they are not part of this commit. This function returns zero in case
+ * of success and a negative error code in case of failure.
+ */
+int ubifs_lpt_start_commit(struct ubifs_info *c)
+{
+ int err, cnt;
+
+ dbg_lp("");
+
+ mutex_lock(&c->lp_mutex);
+ err = dbg_check_ltab(c);
+ if (err)
+ goto out;
+
+ if (c->check_lpt_free) {
+ /*
+ * We ensure there is enough free space in
+ * ubifs_lpt_post_commit() by marking nodes dirty. That
+ * information is lost when we unmount, so we also need
+ * to check free space once after mounting also.
+ */
+ c->check_lpt_free = 0;
+ while (need_write_all(c)) {
+ mutex_unlock(&c->lp_mutex);
+ err = lpt_gc(c);
+ if (err)
+ return err;
+ mutex_lock(&c->lp_mutex);
+ }
+ }
+
+ lpt_tgc_start(c);
+
+ if (!c->dirty_pn_cnt) {
+ dbg_cmt("no cnodes to commit");
+ err = 0;
+ goto out;
+ }
+
+ if (!c->big_lpt && need_write_all(c)) {
+ /* If needed, write everything */
+ err = make_tree_dirty(c);
+ if (err)
+ goto out;
+ lpt_tgc_start(c);
+ }
+
+ if (c->big_lpt)
+ populate_lsave(c);
+
+ cnt = get_cnodes_to_commit(c);
+ ubifs_assert(cnt != 0);
+
+ err = layout_cnodes(c);
+ if (err)
+ goto out;
+
+ /* Copy the LPT's own lprops for end commit to write */
+ memcpy(c->ltab_cmt, c->ltab,
+ sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
+ c->lpt_drty_flgs &= ~(LTAB_DIRTY | LSAVE_DIRTY);
+
+out:
+ mutex_unlock(&c->lp_mutex);
+ return err;
+}
+
+/**
+ * free_obsolete_cnodes - free obsolete cnodes for commit end.
+ * @c: UBIFS file-system description object
+ */
+static void free_obsolete_cnodes(struct ubifs_info *c)
+{
+ struct ubifs_cnode *cnode, *cnext;
+
+ cnext = c->lpt_cnext;
+ if (!cnext)
+ return;
+ do {
+ cnode = cnext;
+ cnext = cnode->cnext;
+ if (test_bit(OBSOLETE_CNODE, &cnode->flags))
+ kfree(cnode);
+ else
+ cnode->cnext = NULL;
+ } while (cnext != c->lpt_cnext);
+ c->lpt_cnext = NULL;
+}
+
+/**
+ * ubifs_lpt_end_commit - finish the commit operation.
+ * @c: the UBIFS file-system description object
+ *
+ * This function has to be called when the commit operation finishes. It
+ * flushes the changes which were "frozen" by 'ubifs_lprops_start_commit()' to
+ * the media. Returns zero in case of success and a negative error code in case
+ * of failure.
+ */
+int ubifs_lpt_end_commit(struct ubifs_info *c)
+{
+ int err;
+
+ dbg_lp("");
+
+ if (!c->lpt_cnext)
+ return 0;
+
+ err = write_cnodes(c);
+ if (err)
+ return err;
+
+ mutex_lock(&c->lp_mutex);
+ free_obsolete_cnodes(c);
+ mutex_unlock(&c->lp_mutex);
+
+ return 0;
+}
+
+/**
+ * ubifs_lpt_post_commit - post commit LPT trivial GC and LPT GC.
+ * @c: UBIFS file-system description object
+ *
+ * LPT trivial GC is completed after a commit. Also LPT GC is done after a
+ * commit for the "big" LPT model.
+ */
+int ubifs_lpt_post_commit(struct ubifs_info *c)
+{
+ int err;
+
+ mutex_lock(&c->lp_mutex);
+ err = lpt_tgc_end(c);
+ if (err)
+ goto out;
+ if (c->big_lpt)
+ while (need_write_all(c)) {
+ mutex_unlock(&c->lp_mutex);
+ err = lpt_gc(c);
+ if (err)
+ return err;
+ mutex_lock(&c->lp_mutex);
+ }
+out:
+ mutex_unlock(&c->lp_mutex);
+ return err;
+}
+
+/**
+ * first_nnode - find the first nnode in memory.
+ * @c: UBIFS file-system description object
+ * @hght: height of tree where nnode found is returned here
+ *
+ * This function returns a pointer to the nnode found or %NULL if no nnode is
+ * found. This function is a helper to 'ubifs_lpt_free()'.
+ */
+static struct ubifs_nnode *first_nnode(struct ubifs_info *c, int *hght)
+{
+ struct ubifs_nnode *nnode;
+ int h, i, found;
+
+ nnode = c->nroot;
+ *hght = 0;
+ if (!nnode)
+ return NULL;
+ for (h = 1; h < c->lpt_hght; h++) {
+ found = 0;
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ if (nnode->nbranch[i].nnode) {
+ found = 1;
+ nnode = nnode->nbranch[i].nnode;
+ *hght = h;
+ break;
+ }
+ }
+ if (!found)
+ break;
+ }
+ return nnode;
+}
+
+/**
+ * next_nnode - find the next nnode in memory.
+ * @c: UBIFS file-system description object
+ * @nnode: nnode from which to start.
+ * @hght: height of tree where nnode is, is passed and returned here
+ *
+ * This function returns a pointer to the nnode found or %NULL if no nnode is
+ * found. This function is a helper to 'ubifs_lpt_free()'.
+ */
+static struct ubifs_nnode *next_nnode(struct ubifs_info *c,
+ struct ubifs_nnode *nnode, int *hght)
+{
+ struct ubifs_nnode *parent;
+ int iip, h, i, found;
+
+ parent = nnode->parent;
+ if (!parent)
+ return NULL;
+ if (nnode->iip == UBIFS_LPT_FANOUT - 1) {
+ *hght -= 1;
+ return parent;
+ }
+ for (iip = nnode->iip + 1; iip < UBIFS_LPT_FANOUT; iip++) {
+ nnode = parent->nbranch[iip].nnode;
+ if (nnode)
+ break;
+ }
+ if (!nnode) {
+ *hght -= 1;
+ return parent;
+ }
+ for (h = *hght + 1; h < c->lpt_hght; h++) {
+ found = 0;
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ if (nnode->nbranch[i].nnode) {
+ found = 1;
+ nnode = nnode->nbranch[i].nnode;
+ *hght = h;
+ break;
+ }
+ }
+ if (!found)
+ break;
+ }
+ return nnode;
+}
+
+/**
+ * ubifs_lpt_free - free resources owned by the LPT.
+ * @c: UBIFS file-system description object
+ * @wr_only: free only resources used for writing
+ */
+void ubifs_lpt_free(struct ubifs_info *c, int wr_only)
+{
+ struct ubifs_nnode *nnode;
+ int i, hght;
+
+ /* Free write-only things first */
+
+ free_obsolete_cnodes(c); /* Leftover from a failed commit */
+
+ vfree(c->ltab_cmt);
+ c->ltab_cmt = NULL;
+ vfree(c->lpt_buf);
+ c->lpt_buf = NULL;
+ kfree(c->lsave);
+ c->lsave = NULL;
+
+ if (wr_only)
+ return;
+
+ /* Now free the rest */
+
+ nnode = first_nnode(c, &hght);
+ while (nnode) {
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++)
+ kfree(nnode->nbranch[i].nnode);
+ nnode = next_nnode(c, nnode, &hght);
+ }
+ for (i = 0; i < LPROPS_HEAP_CNT; i++)
+ kfree(c->lpt_heap[i].arr);
+ kfree(c->dirty_idx.arr);
+ kfree(c->nroot);
+ vfree(c->ltab);
+ kfree(c->lpt_nod_buf);
+}
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+
+/**
+ * dbg_is_all_ff - determine if a buffer contains only 0xff bytes.
+ * @buf: buffer
+ * @len: buffer length
+ */
+static int dbg_is_all_ff(uint8_t *buf, int len)
+{
+ int i;
+
+ for (i = 0; i < len; i++)
+ if (buf[i] != 0xff)
+ return 0;
+ return 1;
+}
+
+/**
+ * dbg_is_nnode_dirty - determine if a nnode is dirty.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB number where nnode was written
+ * @offs: offset where nnode was written
+ */
+static int dbg_is_nnode_dirty(struct ubifs_info *c, int lnum, int offs)
+{
+ struct ubifs_nnode *nnode;
+ int hght;
+
+ /* Entire tree is in memory so first_nnode / next_nnode are ok */
+ nnode = first_nnode(c, &hght);
+ for (; nnode; nnode = next_nnode(c, nnode, &hght)) {
+ struct ubifs_nbranch *branch;
+
+ cond_resched();
+ if (nnode->parent) {
+ branch = &nnode->parent->nbranch[nnode->iip];
+ if (branch->lnum != lnum || branch->offs != offs)
+ continue;
+ if (test_bit(DIRTY_CNODE, &nnode->flags))
+ return 1;
+ return 0;
+ } else {
+ if (c->lpt_lnum != lnum || c->lpt_offs != offs)
+ continue;
+ if (test_bit(DIRTY_CNODE, &nnode->flags))
+ return 1;
+ return 0;
+ }
+ }
+ return 1;
+}
+
+/**
+ * dbg_is_pnode_dirty - determine if a pnode is dirty.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB number where pnode was written
+ * @offs: offset where pnode was written
+ */
+static int dbg_is_pnode_dirty(struct ubifs_info *c, int lnum, int offs)
+{
+ int i, cnt;
+
+ cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT);
+ for (i = 0; i < cnt; i++) {
+ struct ubifs_pnode *pnode;
+ struct ubifs_nbranch *branch;
+
+ cond_resched();
+ pnode = pnode_lookup(c, i);
+ if (IS_ERR(pnode))
+ return PTR_ERR(pnode);
+ branch = &pnode->parent->nbranch[pnode->iip];
+ if (branch->lnum != lnum || branch->offs != offs)
+ continue;
+ if (test_bit(DIRTY_CNODE, &pnode->flags))
+ return 1;
+ return 0;
+ }
+ return 1;
+}
+
+/**
+ * dbg_is_ltab_dirty - determine if a ltab node is dirty.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB number where ltab node was written
+ * @offs: offset where ltab node was written
+ */
+static int dbg_is_ltab_dirty(struct ubifs_info *c, int lnum, int offs)
+{
+ if (lnum != c->ltab_lnum || offs != c->ltab_offs)
+ return 1;
+ return (c->lpt_drty_flgs & LTAB_DIRTY) != 0;
+}
+
+/**
+ * dbg_is_lsave_dirty - determine if a lsave node is dirty.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB number where lsave node was written
+ * @offs: offset where lsave node was written
+ */
+static int dbg_is_lsave_dirty(struct ubifs_info *c, int lnum, int offs)
+{
+ if (lnum != c->lsave_lnum || offs != c->lsave_offs)
+ return 1;
+ return (c->lpt_drty_flgs & LSAVE_DIRTY) != 0;
+}
+
+/**
+ * dbg_is_node_dirty - determine if a node is dirty.
+ * @c: the UBIFS file-system description object
+ * @node_type: node type
+ * @lnum: LEB number where node was written
+ * @offs: offset where node was written
+ */
+static int dbg_is_node_dirty(struct ubifs_info *c, int node_type, int lnum,
+ int offs)
+{
+ switch (node_type) {
+ case UBIFS_LPT_NNODE:
+ return dbg_is_nnode_dirty(c, lnum, offs);
+ case UBIFS_LPT_PNODE:
+ return dbg_is_pnode_dirty(c, lnum, offs);
+ case UBIFS_LPT_LTAB:
+ return dbg_is_ltab_dirty(c, lnum, offs);
+ case UBIFS_LPT_LSAVE:
+ return dbg_is_lsave_dirty(c, lnum, offs);
+ }
+ return 1;
+}
+
+/**
+ * dbg_check_ltab_lnum - check the ltab for a LPT LEB number.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB number where node was written
+ * @offs: offset where node was written
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int dbg_check_ltab_lnum(struct ubifs_info *c, int lnum)
+{
+ int err, len = c->leb_size, dirty = 0, node_type, node_num, node_len;
+ int ret;
+ void *buf = c->dbg_buf;
+
+ dbg_lp("LEB %d", lnum);
+ err = ubi_read(c->ubi, lnum, buf, 0, c->leb_size);
+ if (err) {
+ dbg_msg("ubi_read failed, LEB %d, error %d", lnum, err);
+ return err;
+ }
+ while (1) {
+ if (!is_a_node(c, buf, len)) {
+ int i, pad_len;
+
+ pad_len = get_pad_len(c, buf, len);
+ if (pad_len) {
+ buf += pad_len;
+ len -= pad_len;
+ dirty += pad_len;
+ continue;
+ }
+ if (!dbg_is_all_ff(buf, len)) {
+ dbg_msg("invalid empty space in LEB %d at %d",
+ lnum, c->leb_size - len);
+ err = -EINVAL;
+ }
+ i = lnum - c->lpt_first;
+ if (len != c->ltab[i].free) {
+ dbg_msg("invalid free space in LEB %d "
+ "(free %d, expected %d)",
+ lnum, len, c->ltab[i].free);
+ err = -EINVAL;
+ }
+ if (dirty != c->ltab[i].dirty) {
+ dbg_msg("invalid dirty space in LEB %d "
+ "(dirty %d, expected %d)",
+ lnum, dirty, c->ltab[i].dirty);
+ err = -EINVAL;
+ }
+ return err;
+ }
+ node_type = get_lpt_node_type(c, buf, &node_num);
+ node_len = get_lpt_node_len(c, node_type);
+ ret = dbg_is_node_dirty(c, node_type, lnum, c->leb_size - len);
+ if (ret == 1)
+ dirty += node_len;
+ buf += node_len;
+ len -= node_len;
+ }
+}
+
+/**
+ * dbg_check_ltab - check the free and dirty space in the ltab.
+ * @c: the UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int dbg_check_ltab(struct ubifs_info *c)
+{
+ int lnum, err, i, cnt;
+
+ if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS))
+ return 0;
+
+ /* Bring the entire tree into memory */
+ cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT);
+ for (i = 0; i < cnt; i++) {
+ struct ubifs_pnode *pnode;
+
+ pnode = pnode_lookup(c, i);
+ if (IS_ERR(pnode))
+ return PTR_ERR(pnode);
+ cond_resched();
+ }
+
+ /* Check nodes */
+ err = dbg_check_lpt_nodes(c, (struct ubifs_cnode *)c->nroot, 0, 0);
+ if (err)
+ return err;
+
+ /* Check each LEB */
+ for (lnum = c->lpt_first; lnum <= c->lpt_last; lnum++) {
+ err = dbg_check_ltab_lnum(c, lnum);
+ if (err) {
+ dbg_err("failed at LEB %d", lnum);
+ return err;
+ }
+ }
+
+ dbg_lp("succeeded");
+ return 0;
+}
+
+#endif /* CONFIG_UBIFS_FS_DEBUG */
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ * Adrian Hunter
+ */
+
+/* This file implements reading and writing the master node */
+
+#include "ubifs.h"
+
+/**
+ * scan_for_master - search the valid master node.
+ * @c: UBIFS file-system description object
+ *
+ * This function scans the master node LEBs and search for the latest master
+ * node. Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+static int scan_for_master(struct ubifs_info *c)
+{
+ struct ubifs_scan_leb *sleb;
+ struct ubifs_scan_node *snod;
+ int lnum, offs = 0, nodes_cnt;
+
+ lnum = UBIFS_MST_LNUM;
+
+ sleb = ubifs_scan(c, lnum, 0, c->sbuf);
+ if (IS_ERR(sleb))
+ return PTR_ERR(sleb);
+ nodes_cnt = sleb->nodes_cnt;
+ if (nodes_cnt > 0) {
+ snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node,
+ list);
+ if (snod->type != UBIFS_MST_NODE)
+ goto out;
+ memcpy(c->mst_node, snod->node, snod->len);
+ offs = snod->offs;
+ }
+ ubifs_scan_destroy(sleb);
+
+ lnum += 1;
+
+ sleb = ubifs_scan(c, lnum, 0, c->sbuf);
+ if (IS_ERR(sleb))
+ return PTR_ERR(sleb);
+ if (sleb->nodes_cnt != nodes_cnt)
+ goto out;
+ if (!sleb->nodes_cnt)
+ goto out;
+ snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node, list);
+ if (snod->type != UBIFS_MST_NODE)
+ goto out;
+ if (snod->offs != offs)
+ goto out;
+ if (memcmp((void *)c->mst_node + UBIFS_CH_SZ,
+ (void *)snod->node + UBIFS_CH_SZ,
+ UBIFS_MST_NODE_SZ - UBIFS_CH_SZ))
+ goto out;
+ c->mst_offs = offs;
+ ubifs_scan_destroy(sleb);
+ return 0;
+
+out:
+ ubifs_scan_destroy(sleb);
+ return -EINVAL;
+}
+
+/**
+ * validate_master - validate master node.
+ * @c: UBIFS file-system description object
+ *
+ * This function validates data which was read from master node. Returns zero
+ * if the data is all right and %-EINVAL if not.
+ */
+static int validate_master(const struct ubifs_info *c)
+{
+ long long main_sz;
+ int err;
+
+ if (c->max_sqnum >= SQNUM_WATERMARK) {
+ err = 1;
+ goto out;
+ }
+
+ if (c->cmt_no >= c->max_sqnum) {
+ err = 2;
+ goto out;
+ }
+
+ if (c->highest_inum >= INUM_WATERMARK) {
+ err = 3;
+ goto out;
+ }
+
+ if (c->lhead_lnum < UBIFS_LOG_LNUM ||
+ c->lhead_lnum >= UBIFS_LOG_LNUM + c->log_lebs ||
+ c->lhead_offs < 0 || c->lhead_offs >= c->leb_size ||
+ c->lhead_offs & (c->min_io_size - 1)) {
+ err = 4;
+ goto out;
+ }
+
+ if (c->zroot.lnum >= c->leb_cnt || c->zroot.lnum < c->main_first ||
+ c->zroot.offs >= c->leb_size || c->zroot.offs & 7) {
+ err = 5;
+ goto out;
+ }
+
+ if (c->zroot.len < c->ranges[UBIFS_IDX_NODE].min_len ||
+ c->zroot.len > c->ranges[UBIFS_IDX_NODE].max_len) {
+ err = 6;
+ goto out;
+ }
+
+ if (c->gc_lnum >= c->leb_cnt || c->gc_lnum < c->main_first) {
+ err = 7;
+ goto out;
+ }
+
+ if (c->ihead_lnum >= c->leb_cnt || c->ihead_lnum < c->main_first ||
+ c->ihead_offs % c->min_io_size || c->ihead_offs < 0 ||
+ c->ihead_offs > c->leb_size || c->ihead_offs & 7) {
+ err = 8;
+ goto out;
+ }
+
+ main_sz = (long long)c->main_lebs * c->leb_size;
+ if (c->old_idx_sz & 7 || c->old_idx_sz >= main_sz) {
+ err = 9;
+ goto out;
+ }
+
+ if (c->lpt_lnum < c->lpt_first || c->lpt_lnum > c->lpt_last ||
+ c->lpt_offs < 0 || c->lpt_offs + c->nnode_sz > c->leb_size) {
+ err = 10;
+ goto out;
+ }
+
+ if (c->nhead_lnum < c->lpt_first || c->nhead_lnum > c->lpt_last ||
+ c->nhead_offs < 0 || c->nhead_offs % c->min_io_size ||
+ c->nhead_offs > c->leb_size) {
+ err = 11;
+ goto out;
+ }
+
+ if (c->ltab_lnum < c->lpt_first || c->ltab_lnum > c->lpt_last ||
+ c->ltab_offs < 0 ||
+ c->ltab_offs + c->ltab_sz > c->leb_size) {
+ err = 12;
+ goto out;
+ }
+
+ if (c->big_lpt && (c->lsave_lnum < c->lpt_first ||
+ c->lsave_lnum > c->lpt_last || c->lsave_offs < 0 ||
+ c->lsave_offs + c->lsave_sz > c->leb_size)) {
+ err = 13;
+ goto out;
+ }
+
+ if (c->lscan_lnum < c->main_first || c->lscan_lnum >= c->leb_cnt) {
+ err = 14;
+ goto out;
+ }
+
+ if (c->lst.empty_lebs < 0 || c->lst.empty_lebs > c->main_lebs - 2) {
+ err = 15;
+ goto out;
+ }
+
+ if (c->lst.idx_lebs < 0 || c->lst.idx_lebs > c->main_lebs - 1) {
+ err = 16;
+ goto out;
+ }
+
+ if (c->lst.total_free < 0 || c->lst.total_free > main_sz ||
+ c->lst.total_free & 7) {
+ err = 17;
+ goto out;
+ }
+
+ if (c->lst.total_dirty < 0 || (c->lst.total_dirty & 7)) {
+ err = 18;
+ goto out;
+ }
+
+ if (c->lst.total_used < 0 || (c->lst.total_used & 7)) {
+ err = 19;
+ goto out;
+ }
+
+ if (c->lst.total_free + c->lst.total_dirty +
+ c->lst.total_used > main_sz) {
+ err = 20;
+ goto out;
+ }
+
+ if (c->lst.total_dead + c->lst.total_dark +
+ c->lst.total_used + c->old_idx_sz > main_sz) {
+ err = 21;
+ goto out;
+ }
+
+ if (c->lst.total_dead < 0 ||
+ c->lst.total_dead > c->lst.total_free + c->lst.total_dirty ||
+ c->lst.total_dead & 7) {
+ err = 22;
+ goto out;
+ }
+
+ if (c->lst.total_dark < 0 ||
+ c->lst.total_dark > c->lst.total_free + c->lst.total_dirty ||
+ c->lst.total_dark & 7) {
+ err = 23;
+ goto out;
+ }
+
+ return 0;
+
+out:
+ ubifs_err("bad master node at offset %d error %d", c->mst_offs, err);
+ dbg_dump_node(c, c->mst_node);
+ return -EINVAL;
+}
+
+/**
+ * ubifs_read_master - read master node.
+ * @c: UBIFS file-system description object
+ *
+ * This function finds and reads the master node during file-system mount. If
+ * the flash is empty, it creates default master node as well. Returns zero in
+ * case of success and a negative error code in case of failure.
+ */
+int ubifs_read_master(struct ubifs_info *c)
+{
+ int err, old_leb_cnt;
+
+ c->mst_node = kzalloc(c->mst_node_alsz, GFP_KERNEL);
+ if (!c->mst_node)
+ return -ENOMEM;
+
+ err = scan_for_master(c);
+ if (err) {
+ err = ubifs_recover_master_node(c);
+ if (err)
+ /*
+ * Note, we do not free 'c->mst_node' here because the
+ * unmount routine will take care of this.
+ */
+ return err;
+ }
+
+ /* Make sure that the recovery flag is clear */
+ c->mst_node->flags &= cpu_to_le32(~UBIFS_MST_RCVRY);
+
+ c->max_sqnum = le64_to_cpu(c->mst_node->ch.sqnum);
+ c->highest_inum = le64_to_cpu(c->mst_node->highest_inum);
+ c->cmt_no = le64_to_cpu(c->mst_node->cmt_no);
+ c->zroot.lnum = le32_to_cpu(c->mst_node->root_lnum);
+ c->zroot.offs = le32_to_cpu(c->mst_node->root_offs);
+ c->zroot.len = le32_to_cpu(c->mst_node->root_len);
+ c->lhead_lnum = le32_to_cpu(c->mst_node->log_lnum);
+ c->gc_lnum = le32_to_cpu(c->mst_node->gc_lnum);
+ c->ihead_lnum = le32_to_cpu(c->mst_node->ihead_lnum);
+ c->ihead_offs = le32_to_cpu(c->mst_node->ihead_offs);
+ c->old_idx_sz = le64_to_cpu(c->mst_node->index_size);
+ c->lpt_lnum = le32_to_cpu(c->mst_node->lpt_lnum);
+ c->lpt_offs = le32_to_cpu(c->mst_node->lpt_offs);
+ c->nhead_lnum = le32_to_cpu(c->mst_node->nhead_lnum);
+ c->nhead_offs = le32_to_cpu(c->mst_node->nhead_offs);
+ c->ltab_lnum = le32_to_cpu(c->mst_node->ltab_lnum);
+ c->ltab_offs = le32_to_cpu(c->mst_node->ltab_offs);
+ c->lsave_lnum = le32_to_cpu(c->mst_node->lsave_lnum);
+ c->lsave_offs = le32_to_cpu(c->mst_node->lsave_offs);
+ c->lscan_lnum = le32_to_cpu(c->mst_node->lscan_lnum);
+ c->lst.empty_lebs = le32_to_cpu(c->mst_node->empty_lebs);
+ c->lst.idx_lebs = le32_to_cpu(c->mst_node->idx_lebs);
+ old_leb_cnt = le32_to_cpu(c->mst_node->leb_cnt);
+ c->lst.total_free = le64_to_cpu(c->mst_node->total_free);
+ c->lst.total_dirty = le64_to_cpu(c->mst_node->total_dirty);
+ c->lst.total_used = le64_to_cpu(c->mst_node->total_used);
+ c->lst.total_dead = le64_to_cpu(c->mst_node->total_dead);
+ c->lst.total_dark = le64_to_cpu(c->mst_node->total_dark);
+
+ c->calc_idx_sz = c->old_idx_sz;
+
+ if (c->mst_node->flags & cpu_to_le32(UBIFS_MST_NO_ORPHS))
+ c->no_orphs = 1;
+
+ if (old_leb_cnt != c->leb_cnt) {
+ /* The file system has been resized */
+ int growth = c->leb_cnt - old_leb_cnt;
+
+ if (c->leb_cnt < old_leb_cnt ||
+ c->leb_cnt < UBIFS_MIN_LEB_CNT) {
+ ubifs_err("bad leb_cnt on master node");
+ dbg_dump_node(c, c->mst_node);
+ return -EINVAL;
+ }
+
+ dbg_mnt("Auto resizing (master) from %d LEBs to %d LEBs",
+ old_leb_cnt, c->leb_cnt);
+ c->lst.empty_lebs += growth;
+ c->lst.total_free += growth * (long long)c->leb_size;
+ c->lst.total_dark += growth * (long long)c->dark_wm;
+
+ /*
+ * Reflect changes back onto the master node. N.B. the master
+ * node gets written immediately whenever mounting (or
+ * remounting) in read-write mode, so we do not need to write it
+ * here.
+ */
+ c->mst_node->leb_cnt = cpu_to_le32(c->leb_cnt);
+ c->mst_node->empty_lebs = cpu_to_le32(c->lst.empty_lebs);
+ c->mst_node->total_free = cpu_to_le64(c->lst.total_free);
+ c->mst_node->total_dark = cpu_to_le64(c->lst.total_dark);
+ }
+
+ err = validate_master(c);
+ if (err)
+ return err;
+
+ err = dbg_old_index_check_init(c, &c->zroot);
+
+ return err;
+}
+
+/**
+ * ubifs_write_master - write master node.
+ * @c: UBIFS file-system description object
+ *
+ * This function writes the master node. The caller has to take the
+ * @c->mst_mutex lock before calling this function. Returns zero in case of
+ * success and a negative error code in case of failure. The master node is
+ * written twice to enable recovery.
+ */
+int ubifs_write_master(struct ubifs_info *c)
+{
+ int err, lnum, offs, len;
+
+ if (c->ro_media)
+ return -EINVAL;
+
+ lnum = UBIFS_MST_LNUM;
+ offs = c->mst_offs + c->mst_node_alsz;
+ len = UBIFS_MST_NODE_SZ;
+
+ if (offs + UBIFS_MST_NODE_SZ > c->leb_size) {
+ err = ubifs_leb_unmap(c, lnum);
+ if (err)
+ return err;
+ offs = 0;
+ }
+
+ c->mst_offs = offs;
+ c->mst_node->highest_inum = cpu_to_le64(c->highest_inum);
+
+ err = ubifs_write_node(c, c->mst_node, len, lnum, offs, UBI_SHORTTERM);
+ if (err)
+ return err;
+
+ lnum += 1;
+
+ if (offs == 0) {
+ err = ubifs_leb_unmap(c, lnum);
+ if (err)
+ return err;
+ }
+ err = ubifs_write_node(c, c->mst_node, len, lnum, offs, UBI_SHORTTERM);
+
+ return err;
+}
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ * Adrian Hunter
+ */
+
+/*
+ * This file contains miscellaneous helper functions.
+ */
+
+#ifndef __UBIFS_MISC_H__
+#define __UBIFS_MISC_H__
+
+/**
+ * ubifs_zn_dirty - check if znode is dirty.
+ * @znode: znode to check
+ *
+ * This helper function returns %1 if @znode is dirty and %0 otherwise.
+ */
+static inline int ubifs_zn_dirty(const struct ubifs_znode *znode)
+{
+ return !!test_bit(DIRTY_ZNODE, &znode->flags);
+}
+
+/**
+ * ubifs_wake_up_bgt - wake up background thread.
+ * @c: UBIFS file-system description object
+ */
+static inline void ubifs_wake_up_bgt(struct ubifs_info *c)
+{
+ if (c->bgt && !c->need_bgt) {
+ c->need_bgt = 1;
+ wake_up_process(c->bgt);
+ }
+}
+
+/**
+ * ubifs_tnc_find_child - find next child in znode.
+ * @znode: znode to search at
+ * @start: the zbranch index to start at
+ *
+ * This helper function looks for znode child starting at index @start. Returns
+ * the child or %NULL if no children were found.
+ */
+static inline struct ubifs_znode *
+ubifs_tnc_find_child(struct ubifs_znode *znode, int start)
+{
+ while (start < znode->child_cnt) {
+ if (znode->zbranch[start].znode)
+ return znode->zbranch[start].znode;
+ start += 1;
+ }
+
+ return NULL;
+}
+
+/**
+ * ubifs_inode - get UBIFS inode information by VFS 'struct inode' object.
+ * @inode: the VFS 'struct inode' pointer
+ */
+static inline struct ubifs_inode *ubifs_inode(const struct inode *inode)
+{
+ return container_of(inode, struct ubifs_inode, vfs_inode);
+}
+
+/**
+ * ubifs_ro_mode - switch UBIFS to read read-only mode.
+ * @c: UBIFS file-system description object
+ * @err: error code which is the reason of switching to R/O mode
+ */
+static inline void ubifs_ro_mode(struct ubifs_info *c, int err)
+{
+ if (!c->ro_media) {
+ c->ro_media = 1;
+ ubifs_warn("switched to read-only mode, error %d", err);
+ dbg_dump_stack();
+ }
+}
+
+/**
+ * ubifs_compr_present - check if compressor was compiled in.
+ * @compr_type: compressor type to check
+ *
+ * This function returns %1 of compressor of type @compr_type is present, and
+ * %0 if not.
+ */
+static inline int ubifs_compr_present(int compr_type)
+{
+ ubifs_assert(compr_type >= 0 && compr_type < UBIFS_COMPR_TYPES_CNT);
+ return !!ubifs_compressors[compr_type]->capi_name;
+}
+
+/**
+ * ubifs_compr_name - get compressor name string by its type.
+ * @compr_type: compressor type
+ *
+ * This function returns compressor type string.
+ */
+static inline const char *ubifs_compr_name(int compr_type)
+{
+ ubifs_assert(compr_type >= 0 && compr_type < UBIFS_COMPR_TYPES_CNT);
+ return ubifs_compressors[compr_type]->name;
+}
+
+/**
+ * ubifs_wbuf_sync - synchronize write-buffer.
+ * @wbuf: write-buffer to synchronize
+ *
+ * This is the same as as 'ubifs_wbuf_sync_nolock()' but it does not assume
+ * that the write-buffer is already locked.
+ */
+static inline int ubifs_wbuf_sync(struct ubifs_wbuf *wbuf)
+{
+ int err;
+
+ mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
+ err = ubifs_wbuf_sync_nolock(wbuf);
+ mutex_unlock(&wbuf->io_mutex);
+ return err;
+}
+
+/**
+ * ubifs_leb_unmap - unmap an LEB.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to unmap
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static inline int ubifs_leb_unmap(const struct ubifs_info *c, int lnum)
+{
+ int err;
+
+ if (c->ro_media)
+ return -EROFS;
+ err = ubi_leb_unmap(c->ubi, lnum);
+ if (err) {
+ ubifs_err("unmap LEB %d failed, error %d", lnum, err);
+ return err;
+ }
+
+ return 0;
+}
+
+/**
+ * ubifs_leb_write - write to a LEB.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to write
+ * @buf: buffer to write from
+ * @offs: offset within LEB to write to
+ * @len: length to write
+ * @dtype: data type
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static inline int ubifs_leb_write(const struct ubifs_info *c, int lnum,
+ const void *buf, int offs, int len, int dtype)
+{
+ int err;
+
+ if (c->ro_media)
+ return -EROFS;
+ err = ubi_leb_write(c->ubi, lnum, buf, offs, len, dtype);
+ if (err) {
+ ubifs_err("writing %d bytes at %d:%d, error %d",
+ len, lnum, offs, err);
+ return err;
+ }
+
+ return 0;
+}
+
+/**
+ * ubifs_leb_change - atomic LEB change.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to write
+ * @buf: buffer to write from
+ * @len: length to write
+ * @dtype: data type
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static inline int ubifs_leb_change(const struct ubifs_info *c, int lnum,
+ const void *buf, int len, int dtype)
+{
+ int err;
+
+ if (c->ro_media)
+ return -EROFS;
+ err = ubi_leb_change(c->ubi, lnum, buf, len, dtype);
+ if (err) {
+ ubifs_err("changing %d bytes in LEB %d, error %d",
+ len, lnum, err);
+ return err;
+ }
+
+ return 0;
+}
+
+/**
+ * ubifs_encode_dev - encode device node IDs.
+ * @dev: UBIFS device node information
+ * @rdev: device IDs to encode
+ *
+ * This is a helper function which encodes major/minor numbers of a device node
+ * into UBIFS device node description. We use standard Linux "new" and "huge"
+ * encodings.
+ */
+static inline int ubifs_encode_dev(union ubifs_dev_desc *dev, dev_t rdev)
+{
+ if (new_valid_dev(rdev)) {
+ dev->new = cpu_to_le32(new_encode_dev(rdev));
+ return sizeof(dev->new);
+ } else {
+ dev->huge = cpu_to_le64(huge_encode_dev(rdev));
+ return sizeof(dev->huge);
+ }
+}
+
+/**
+ * ubifs_add_dirt - add dirty space to LEB properties.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB to add dirty space for
+ * @dirty: dirty space to add
+ *
+ * This is a helper function which increased amount of dirty LEB space. Returns
+ * zero in case of success and a negative error code in case of failure.
+ */
+static inline int ubifs_add_dirt(struct ubifs_info *c, int lnum, int dirty)
+{
+ return ubifs_update_one_lp(c, lnum, LPROPS_NC, dirty, 0, 0);
+}
+
+/**
+ * ubifs_return_leb - return LEB to lprops.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB to return
+ *
+ * This helper function cleans the "taken" flag of a logical eraseblock in the
+ * lprops. Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+static inline int ubifs_return_leb(struct ubifs_info *c, int lnum)
+{
+ return ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0,
+ LPROPS_TAKEN, 0);
+}
+
+/**
+ * ubifs_idx_node_sz - return index node size.
+ * @c: the UBIFS file-system description object
+ * @child_cnt: number of children of this index node
+ */
+static inline int ubifs_idx_node_sz(const struct ubifs_info *c, int child_cnt)
+{
+ return UBIFS_IDX_NODE_SZ + (UBIFS_BRANCH_SZ + c->key_len) * child_cnt;
+}
+
+/**
+ * ubifs_idx_branch - return pointer to an index branch.
+ * @c: the UBIFS file-system description object
+ * @idx: index node
+ * @bnum: branch number
+ */
+static inline
+struct ubifs_branch *ubifs_idx_branch(const struct ubifs_info *c,
+ const struct ubifs_idx_node *idx,
+ int bnum)
+{
+ return (struct ubifs_branch *)((void *)idx->branches +
+ (UBIFS_BRANCH_SZ + c->key_len) * bnum);
+}
+
+/**
+ * ubifs_idx_key - return pointer to an index key.
+ * @c: the UBIFS file-system description object
+ * @idx: index node
+ */
+static inline void *ubifs_idx_key(const struct ubifs_info *c,
+ const struct ubifs_idx_node *idx)
+{
+ return (void *)((struct ubifs_branch *)idx->branches)->key;
+}
+
+/**
+ * ubifs_reported_space - calculate reported free space.
+ * @c: the UBIFS file-system description object
+ * @free: amount of free space
+ *
+ * This function calculates amount of free space which will be reported to
+ * user-space. User-space application tend to expect that if the file-system
+ * (e.g., via the 'statfs()' call) reports that it has N bytes available, they
+ * are able to write a file of size N. UBIFS attaches node headers to each data
+ * node and it has to write indexind nodes as well. This introduces additional
+ * overhead, and UBIFS it has to report sligtly less free space to meet the
+ * above expectetion.
+ *
+ * This function assumes free space is made up of uncompressed data nodes and
+ * full index nodes (one per data node, doubled because we always allow enough
+ * space to write the index twice).
+ *
+ * Note, the calculation is pessimistic, which means that most of the time
+ * UBIFS reports less space than it actually has.
+ */
+static inline long long ubifs_reported_space(const struct ubifs_info *c,
+ uint64_t free)
+{
+ int divisor, factor;
+
+ divisor = UBIFS_MAX_DATA_NODE_SZ + (c->max_idx_node_sz << 1);
+ factor = UBIFS_MAX_DATA_NODE_SZ - UBIFS_DATA_NODE_SZ;
+ do_div(free, divisor);
+
+ return free * factor;
+}
+
+/**
+ * ubifs_current_time - round current time to time granularity.
+ * @inode: inode
+ */
+static inline struct timespec ubifs_current_time(struct inode *inode)
+{
+ return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
+ current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
+}
+
+#endif /* __UBIFS_MISC_H__ */
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Author: Adrian Hunter
+ */
+
+#include "ubifs.h"
+
+/*
+ * An orphan is an inode number whose inode node has been committed to the index
+ * with a link count of zero. That happens when an open file is deleted
+ * (unlinked) and then a commit is run. In the normal course of events the inode
+ * would be deleted when the file is closed. However in the case of an unclean
+ * unmount, orphans need to be accounted for. After an unclean unmount, the
+ * orphans' inodes must be deleted which means either scanning the entire index
+ * looking for them, or keeping a list on flash somewhere. This unit implements
+ * the latter approach.
+ *
+ * The orphan area is a fixed number of LEBs situated between the LPT area and
+ * the main area. The number of orphan area LEBs is specified when the file
+ * system is created. The minimum number is 1. The size of the orphan area
+ * should be so that it can hold the maximum number of orphans that are expected
+ * to ever exist at one time.
+ *
+ * The number of orphans that can fit in a LEB is:
+ *
+ * (c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64)
+ *
+ * For example: a 15872 byte LEB can fit 1980 orphans so 1 LEB may be enough.
+ *
+ * Orphans are accumulated in a rb-tree. When an inode's link count drops to
+ * zero, the inode number is added to the rb-tree. It is removed from the tree
+ * when the inode is deleted. Any new orphans that are in the orphan tree when
+ * the commit is run, are written to the orphan area in 1 or more orph nodes.
+ * If the orphan area is full, it is consolidated to make space. There is
+ * always enough space because validation prevents the user from creating more
+ * than the maximum number of orphans allowed.
+ */
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+static int dbg_check_orphans(struct ubifs_info *c);
+#else
+#define dbg_check_orphans(c) 0
+#endif
+
+/**
+ * ubifs_add_orphan - add an orphan.
+ * @c: UBIFS file-system description object
+ * @inum: orphan inode number
+ *
+ * Add an orphan. This function is called when an inodes link count drops to
+ * zero.
+ */
+int ubifs_add_orphan(struct ubifs_info *c, ino_t inum)
+{
+ struct ubifs_orphan *orphan, *o;
+ struct rb_node **p, *parent = NULL;
+
+ orphan = kzalloc(sizeof(struct ubifs_orphan), GFP_NOFS);
+ if (!orphan)
+ return -ENOMEM;
+ orphan->inum = inum;
+ orphan->new = 1;
+
+ spin_lock(&c->orphan_lock);
+ if (c->tot_orphans >= c->max_orphans) {
+ spin_unlock(&c->orphan_lock);
+ kfree(orphan);
+ return -ENFILE;
+ }
+ p = &c->orph_tree.rb_node;
+ while (*p) {
+ parent = *p;
+ o = rb_entry(parent, struct ubifs_orphan, rb);
+ if (inum < o->inum)
+ p = &(*p)->rb_left;
+ else if (inum > o->inum)
+ p = &(*p)->rb_right;
+ else {
+ dbg_err("orphaned twice");
+ spin_unlock(&c->orphan_lock);
+ kfree(orphan);
+ return 0;
+ }
+ }
+ c->tot_orphans += 1;
+ c->new_orphans += 1;
+ rb_link_node(&orphan->rb, parent, p);
+ rb_insert_color(&orphan->rb, &c->orph_tree);
+ list_add_tail(&orphan->list, &c->orph_list);
+ list_add_tail(&orphan->new_list, &c->orph_new);
+ spin_unlock(&c->orphan_lock);
+ dbg_gen("ino %lu", inum);
+ return 0;
+}
+
+/**
+ * ubifs_delete_orphan - delete an orphan.
+ * @c: UBIFS file-system description object
+ * @inum: orphan inode number
+ *
+ * Delete an orphan. This function is called when an inode is deleted.
+ */
+void ubifs_delete_orphan(struct ubifs_info *c, ino_t inum)
+{
+ struct ubifs_orphan *o;
+ struct rb_node *p;
+
+ spin_lock(&c->orphan_lock);
+ p = c->orph_tree.rb_node;
+ while (p) {
+ o = rb_entry(p, struct ubifs_orphan, rb);
+ if (inum < o->inum)
+ p = p->rb_left;
+ else if (inum > o->inum)
+ p = p->rb_right;
+ else {
+ if (o->dnext) {
+ spin_unlock(&c->orphan_lock);
+ dbg_gen("deleted twice ino %lu", inum);
+ return;
+ }
+ if (o->cnext) {
+ o->dnext = c->orph_dnext;
+ c->orph_dnext = o;
+ spin_unlock(&c->orphan_lock);
+ dbg_gen("delete later ino %lu", inum);
+ return;
+ }
+ rb_erase(p, &c->orph_tree);
+ list_del(&o->list);
+ c->tot_orphans -= 1;
+ if (o->new) {
+ list_del(&o->new_list);
+ c->new_orphans -= 1;
+ }
+ spin_unlock(&c->orphan_lock);
+ kfree(o);
+ dbg_gen("inum %lu", inum);
+ return;
+ }
+ }
+ spin_unlock(&c->orphan_lock);
+ dbg_err("missing orphan ino %lu", inum);
+ dbg_dump_stack();
+}
+
+/**
+ * ubifs_orphan_start_commit - start commit of orphans.
+ * @c: UBIFS file-system description object
+ *
+ * Start commit of orphans.
+ */
+int ubifs_orphan_start_commit(struct ubifs_info *c)
+{
+ struct ubifs_orphan *orphan, **last;
+
+ spin_lock(&c->orphan_lock);
+ last = &c->orph_cnext;
+ list_for_each_entry(orphan, &c->orph_new, new_list) {
+ ubifs_assert(orphan->new);
+ orphan->new = 0;
+ *last = orphan;
+ last = &orphan->cnext;
+ }
+ *last = orphan->cnext;
+ c->cmt_orphans = c->new_orphans;
+ c->new_orphans = 0;
+ dbg_cmt("%d orphans to commit", c->cmt_orphans);
+ INIT_LIST_HEAD(&c->orph_new);
+ if (c->tot_orphans == 0)
+ c->no_orphs = 1;
+ else
+ c->no_orphs = 0;
+ spin_unlock(&c->orphan_lock);
+ return 0;
+}
+
+/**
+ * avail_orphs - calculate available space.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns the number of orphans that can be written in the
+ * available space.
+ */
+static int avail_orphs(struct ubifs_info *c)
+{
+ int avail_lebs, avail, gap;
+
+ avail_lebs = c->orph_lebs - (c->ohead_lnum - c->orph_first) - 1;
+ avail = avail_lebs *
+ ((c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64));
+ gap = c->leb_size - c->ohead_offs;
+ if (gap >= UBIFS_ORPH_NODE_SZ + sizeof(__le64))
+ avail += (gap - UBIFS_ORPH_NODE_SZ) / sizeof(__le64);
+ return avail;
+}
+
+/**
+ * tot_avail_orphs - calculate total space.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns the number of orphans that can be written in half
+ * the total space. That leaves half the space for adding new orphans.
+ */
+static int tot_avail_orphs(struct ubifs_info *c)
+{
+ int avail_lebs, avail;
+
+ avail_lebs = c->orph_lebs;
+ avail = avail_lebs *
+ ((c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64));
+ return avail / 2;
+}
+
+/**
+ * do_write_orph_node - write a node
+ * @c: UBIFS file-system description object
+ * @len: length of node
+ * @atomic: write atomically
+ *
+ * This function writes a node to the orphan head from the orphan buffer. If
+ * %atomic is not zero, then the write is done atomically. On success, %0 is
+ * returned, otherwise a negative error code is returned.
+ */
+static int do_write_orph_node(struct ubifs_info *c, int len, int atomic)
+{
+ int err = 0;
+
+ if (atomic) {
+ ubifs_assert(c->ohead_offs == 0);
+ ubifs_prepare_node(c, c->orph_buf, len, 1);
+ len = ALIGN(len, c->min_io_size);
+ err = ubifs_leb_change(c, c->ohead_lnum, c->orph_buf, len,
+ UBI_SHORTTERM);
+ } else {
+ if (c->ohead_offs == 0) {
+ /* Ensure LEB has been unmapped */
+ err = ubifs_leb_unmap(c, c->ohead_lnum);
+ if (err)
+ return err;
+ }
+ err = ubifs_write_node(c, c->orph_buf, len, c->ohead_lnum,
+ c->ohead_offs, UBI_SHORTTERM);
+ }
+ return err;
+}
+
+/**
+ * write_orph_node - write an orph node
+ * @c: UBIFS file-system description object
+ * @atomic: write atomically
+ *
+ * This function builds an orph node from the cnext list and writes it to the
+ * orphan head. On success, %0 is returned, otherwise a negative error code
+ * is returned.
+ */
+static int write_orph_node(struct ubifs_info *c, int atomic)
+{
+ struct ubifs_orphan *orphan, *cnext;
+ struct ubifs_orph_node *orph;
+ int gap, err, len, cnt, i;
+
+ ubifs_assert(c->cmt_orphans > 0);
+ gap = c->leb_size - c->ohead_offs;
+ if (gap < UBIFS_ORPH_NODE_SZ + sizeof(__le64)) {
+ c->ohead_lnum += 1;
+ c->ohead_offs = 0;
+ gap = c->leb_size;
+ if (c->ohead_lnum > c->orph_last) {
+ /*
+ * We limit the number of orphans so that this should
+ * never happen.
+ */
+ ubifs_err("out of space in orphan area");
+ return -EINVAL;
+ }
+ }
+ cnt = (gap - UBIFS_ORPH_NODE_SZ) / sizeof(__le64);
+ if (cnt > c->cmt_orphans)
+ cnt = c->cmt_orphans;
+ len = UBIFS_ORPH_NODE_SZ + cnt * sizeof(__le64);
+ ubifs_assert(c->orph_buf);
+ orph = c->orph_buf;
+ orph->ch.node_type = UBIFS_ORPH_NODE;
+ spin_lock(&c->orphan_lock);
+ cnext = c->orph_cnext;
+ for (i = 0; i < cnt; i++) {
+ orphan = cnext;
+ orph->inos[i] = cpu_to_le64(orphan->inum);
+ cnext = orphan->cnext;
+ orphan->cnext = NULL;
+ }
+ c->orph_cnext = cnext;
+ c->cmt_orphans -= cnt;
+ spin_unlock(&c->orphan_lock);
+ if (c->cmt_orphans)
+ orph->cmt_no = cpu_to_le64(c->cmt_no + 1);
+ else
+ /* Mark the last node of the commit */
+ orph->cmt_no = cpu_to_le64((c->cmt_no + 1) | (1ULL << 63));
+ ubifs_assert(c->ohead_offs + len <= c->leb_size);
+ ubifs_assert(c->ohead_lnum >= c->orph_first);
+ ubifs_assert(c->ohead_lnum <= c->orph_last);
+ err = do_write_orph_node(c, len, atomic);
+ c->ohead_offs += ALIGN(len, c->min_io_size);
+ c->ohead_offs = ALIGN(c->ohead_offs, 8);
+ return err;
+}
+
+/**
+ * write_orph_nodes - write orph nodes until there are no more to commit
+ * @c: UBIFS file-system description object
+ * @atomic: write atomically
+ *
+ * This function writes orph nodes for all the orphans to commit. On success,
+ * %0 is returned, otherwise a negative error code is returned.
+ */
+static int write_orph_nodes(struct ubifs_info *c, int atomic)
+{
+ int err;
+
+ while (c->cmt_orphans > 0) {
+ err = write_orph_node(c, atomic);
+ if (err)
+ return err;
+ }
+ if (atomic) {
+ int lnum;
+
+ /* Unmap any unused LEBs after consolidation */
+ lnum = c->ohead_lnum + 1;
+ for (lnum = c->ohead_lnum + 1; lnum <= c->orph_last; lnum++) {
+ err = ubifs_leb_unmap(c, lnum);
+ if (err)
+ return err;
+ }
+ }
+ return 0;
+}
+
+/**
+ * consolidate - consolidate the orphan area.
+ * @c: UBIFS file-system description object
+ *
+ * This function enables consolidation by putting all the orphans into the list
+ * to commit. The list is in the order that the orphans were added, and the
+ * LEBs are written atomically in order, so at no time can orphans be lost by
+ * an unclean unmount.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int consolidate(struct ubifs_info *c)
+{
+ int tot_avail = tot_avail_orphs(c), err = 0;
+
+ spin_lock(&c->orphan_lock);
+ dbg_cmt("there is space for %d orphans and there are %d",
+ tot_avail, c->tot_orphans);
+ if (c->tot_orphans - c->new_orphans <= tot_avail) {
+ struct ubifs_orphan *orphan, **last;
+ int cnt = 0;
+
+ /* Change the cnext list to include all non-new orphans */
+ last = &c->orph_cnext;
+ list_for_each_entry(orphan, &c->orph_list, list) {
+ if (orphan->new)
+ continue;
+ *last = orphan;
+ last = &orphan->cnext;
+ cnt += 1;
+ }
+ *last = orphan->cnext;
+ ubifs_assert(cnt == c->tot_orphans - c->new_orphans);
+ c->cmt_orphans = cnt;
+ c->ohead_lnum = c->orph_first;
+ c->ohead_offs = 0;
+ } else {
+ /*
+ * We limit the number of orphans so that this should
+ * never happen.
+ */
+ ubifs_err("out of space in orphan area");
+ err = -EINVAL;
+ }
+ spin_unlock(&c->orphan_lock);
+ return err;
+}
+
+/**
+ * commit_orphans - commit orphans.
+ * @c: UBIFS file-system description object
+ *
+ * This function commits orphans to flash. On success, %0 is returned,
+ * otherwise a negative error code is returned.
+ */
+static int commit_orphans(struct ubifs_info *c)
+{
+ int avail, atomic = 0, err;
+
+ ubifs_assert(c->cmt_orphans > 0);
+ avail = avail_orphs(c);
+ if (avail < c->cmt_orphans) {
+ /* Not enough space to write new orphans, so consolidate */
+ err = consolidate(c);
+ if (err)
+ return err;
+ atomic = 1;
+ }
+ err = write_orph_nodes(c, atomic);
+ return err;
+}
+
+/**
+ * erase_deleted - erase the orphans marked for deletion.
+ * @c: UBIFS file-system description object
+ *
+ * During commit, the orphans being committed cannot be deleted, so they are
+ * marked for deletion and deleted by this function. Also, the recovery
+ * adds killed orphans to the deletion list, and therefore they are deleted
+ * here too.
+ */
+static void erase_deleted(struct ubifs_info *c)
+{
+ struct ubifs_orphan *orphan, *dnext;
+
+ spin_lock(&c->orphan_lock);
+ dnext = c->orph_dnext;
+ while (dnext) {
+ orphan = dnext;
+ dnext = orphan->dnext;
+ ubifs_assert(!orphan->new);
+ rb_erase(&orphan->rb, &c->orph_tree);
+ list_del(&orphan->list);
+ c->tot_orphans -= 1;
+ dbg_gen("deleting orphan ino %lu", orphan->inum);
+ kfree(orphan);
+ }
+ c->orph_dnext = NULL;
+ spin_unlock(&c->orphan_lock);
+}
+
+/**
+ * ubifs_orphan_end_commit - end commit of orphans.
+ * @c: UBIFS file-system description object
+ *
+ * End commit of orphans.
+ */
+int ubifs_orphan_end_commit(struct ubifs_info *c)
+{
+ int err;
+
+ if (c->cmt_orphans != 0) {
+ err = commit_orphans(c);
+ if (err)
+ return err;
+ }
+ erase_deleted(c);
+ err = dbg_check_orphans(c);
+ return err;
+}
+
+/**
+ * clear_orphans - erase all LEBs used for orphans.
+ * @c: UBIFS file-system description object
+ *
+ * If recovery is not required, then the orphans from the previous session
+ * are not needed. This function locates the LEBs used to record
+ * orphans, and un-maps them.
+ */
+static int clear_orphans(struct ubifs_info *c)
+{
+ int lnum, err;
+
+ for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {
+ err = ubifs_leb_unmap(c, lnum);
+ if (err)
+ return err;
+ }
+ c->ohead_lnum = c->orph_first;
+ c->ohead_offs = 0;
+ return 0;
+}
+
+/**
+ * insert_dead_orphan - insert an orphan.
+ * @c: UBIFS file-system description object
+ * @inum: orphan inode number
+ *
+ * This function is a helper to the 'do_kill_orphans()' function. The orphan
+ * must be kept until the next commit, so it is added to the rb-tree and the
+ * deletion list.
+ */
+static int insert_dead_orphan(struct ubifs_info *c, ino_t inum)
+{
+ struct ubifs_orphan *orphan, *o;
+ struct rb_node **p, *parent = NULL;
+
+ orphan = kzalloc(sizeof(struct ubifs_orphan), GFP_KERNEL);
+ if (!orphan)
+ return -ENOMEM;
+ orphan->inum = inum;
+
+ p = &c->orph_tree.rb_node;
+ while (*p) {
+ parent = *p;
+ o = rb_entry(parent, struct ubifs_orphan, rb);
+ if (inum < o->inum)
+ p = &(*p)->rb_left;
+ else if (inum > o->inum)
+ p = &(*p)->rb_right;
+ else {
+ /* Already added - no problem */
+ kfree(orphan);
+ return 0;
+ }
+ }
+ c->tot_orphans += 1;
+ rb_link_node(&orphan->rb, parent, p);
+ rb_insert_color(&orphan->rb, &c->orph_tree);
+ list_add_tail(&orphan->list, &c->orph_list);
+ orphan->dnext = c->orph_dnext;
+ c->orph_dnext = orphan;
+ dbg_mnt("ino %lu, new %d, tot %d",
+ inum, c->new_orphans, c->tot_orphans);
+ return 0;
+}
+
+/**
+ * do_kill_orphans - remove orphan inodes from the index.
+ * @c: UBIFS file-system description object
+ * @sleb: scanned LEB
+ * @last_cmt_no: cmt_no of last orph node read is passed and returned here
+ * @outofdate: whether the LEB is out of date is returned here
+ * @last_flagged: whether the end orph node is encountered
+ *
+ * This function is a helper to the 'kill_orphans()' function. It goes through
+ * every orphan node in a LEB and for every inode number recorded, removes
+ * all keys for that inode from the TNC.
+ */
+static int do_kill_orphans(struct ubifs_info *c, struct ubifs_scan_leb *sleb,
+ unsigned long long *last_cmt_no, int *outofdate,
+ int *last_flagged)
+{
+ struct ubifs_scan_node *snod;
+ struct ubifs_orph_node *orph;
+ unsigned long long cmt_no;
+ ino_t inum;
+ int i, n, err, first = 1;
+
+ list_for_each_entry(snod, &sleb->nodes, list) {
+ if (snod->type != UBIFS_ORPH_NODE) {
+ ubifs_err("invalid node type %d in orphan area at "
+ "%d:%d", snod->type, sleb->lnum, snod->offs);
+ dbg_dump_node(c, snod->node);
+ return -EINVAL;
+ }
+
+ orph = snod->node;
+
+ /* Check commit number */
+ cmt_no = le64_to_cpu(orph->cmt_no) & LLONG_MAX;
+ /*
+ * The commit number on the master node may be less, because
+ * of a failed commit. If there are several failed commits in a
+ * row, the commit number written on orph nodes will continue to
+ * increase (because the commit number is adjusted here) even
+ * though the commit number on the master node stays the same
+ * because the master node has not been re-written.
+ */
+ if (cmt_no > c->cmt_no)
+ c->cmt_no = cmt_no;
+ if (cmt_no < *last_cmt_no && *last_flagged) {
+ /*
+ * The last orph node had a higher commit number and was
+ * flagged as the last written for that commit number.
+ * That makes this orph node, out of date.
+ */
+ if (!first) {
+ ubifs_err("out of order commit number %llu in "
+ "orphan node at %d:%d",
+ cmt_no, sleb->lnum, snod->offs);
+ dbg_dump_node(c, snod->node);
+ return -EINVAL;
+ }
+ dbg_rcvry("out of date LEB %d", sleb->lnum);
+ *outofdate = 1;
+ return 0;
+ }
+
+ if (first)
+ first = 0;
+
+ n = (le32_to_cpu(orph->ch.len) - UBIFS_ORPH_NODE_SZ) >> 3;
+ for (i = 0; i < n; i++) {
+ inum = le64_to_cpu(orph->inos[i]);
+ dbg_rcvry("deleting orphaned inode %lu", inum);
+ err = ubifs_tnc_remove_ino(c, inum);
+ if (err)
+ return err;
+ err = insert_dead_orphan(c, inum);
+ if (err)
+ return err;
+ }
+
+ *last_cmt_no = cmt_no;
+ if (le64_to_cpu(orph->cmt_no) & (1ULL << 63)) {
+ dbg_rcvry("last orph node for commit %llu at %d:%d",
+ cmt_no, sleb->lnum, snod->offs);
+ *last_flagged = 1;
+ } else
+ *last_flagged = 0;
+ }
+
+ return 0;
+}
+
+/**
+ * kill_orphans - remove all orphan inodes from the index.
+ * @c: UBIFS file-system description object
+ *
+ * If recovery is required, then orphan inodes recorded during the previous
+ * session (which ended with an unclean unmount) must be deleted from the index.
+ * This is done by updating the TNC, but since the index is not updated until
+ * the next commit, the LEBs where the orphan information is recorded are not
+ * erased until the next commit.
+ */
+static int kill_orphans(struct ubifs_info *c)
+{
+ unsigned long long last_cmt_no = 0;
+ int lnum, err = 0, outofdate = 0, last_flagged = 0;
+
+ c->ohead_lnum = c->orph_first;
+ c->ohead_offs = 0;
+ /* Check no-orphans flag and skip this if no orphans */
+ if (c->no_orphs) {
+ dbg_rcvry("no orphans");
+ return 0;
+ }
+ /*
+ * Orph nodes always start at c->orph_first and are written to each
+ * successive LEB in turn. Generally unused LEBs will have been unmapped
+ * but may contain out of date orph nodes if the unmap didn't go
+ * through. In addition, the last orph node written for each commit is
+ * marked (top bit of orph->cmt_no is set to 1). It is possible that
+ * there are orph nodes from the next commit (i.e. the commit did not
+ * complete successfully). In that case, no orphans will have been lost
+ * due to the way that orphans are written, and any orphans added will
+ * be valid orphans anyway and so can be deleted.
+ */
+ for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {
+ struct ubifs_scan_leb *sleb;
+
+ dbg_rcvry("LEB %d", lnum);
+ sleb = ubifs_scan(c, lnum, 0, c->sbuf);
+ if (IS_ERR(sleb)) {
+ sleb = ubifs_recover_leb(c, lnum, 0, c->sbuf, 0);
+ if (IS_ERR(sleb)) {
+ err = PTR_ERR(sleb);
+ break;
+ }
+ }
+ err = do_kill_orphans(c, sleb, &last_cmt_no, &outofdate,
+ &last_flagged);
+ if (err || outofdate) {
+ ubifs_scan_destroy(sleb);
+ break;
+ }
+ if (sleb->endpt) {
+ c->ohead_lnum = lnum;
+ c->ohead_offs = sleb->endpt;
+ }
+ ubifs_scan_destroy(sleb);
+ }
+ return err;
+}
+
+/**
+ * ubifs_mount_orphans - delete orphan inodes and erase LEBs that recorded them.
+ * @c: UBIFS file-system description object
+ * @unclean: indicates recovery from unclean unmount
+ * @read_only: indicates read only mount
+ *
+ * This function is called when mounting to erase orphans from the previous
+ * session. If UBIFS was not unmounted cleanly, then the inodes recorded as
+ * orphans are deleted.
+ */
+int ubifs_mount_orphans(struct ubifs_info *c, int unclean, int read_only)
+{
+ int err = 0;
+
+ c->max_orphans = tot_avail_orphs(c);
+
+ if (!read_only) {
+ c->orph_buf = vmalloc(c->leb_size);
+ if (!c->orph_buf)
+ return -ENOMEM;
+ }
+
+ if (unclean)
+ err = kill_orphans(c);
+ else if (!read_only)
+ err = clear_orphans(c);
+
+ return err;
+}
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+
+struct check_orphan {
+ struct rb_node rb;
+ ino_t inum;
+};
+
+struct check_info {
+ unsigned long last_ino;
+ unsigned long tot_inos;
+ unsigned long missing;
+ unsigned long long leaf_cnt;
+ struct ubifs_ino_node *node;
+ struct rb_root root;
+};
+
+static int dbg_find_orphan(struct ubifs_info *c, ino_t inum)
+{
+ struct ubifs_orphan *o;
+ struct rb_node *p;
+
+ spin_lock(&c->orphan_lock);
+ p = c->orph_tree.rb_node;
+ while (p) {
+ o = rb_entry(p, struct ubifs_orphan, rb);
+ if (inum < o->inum)
+ p = p->rb_left;
+ else if (inum > o->inum)
+ p = p->rb_right;
+ else {
+ spin_unlock(&c->orphan_lock);
+ return 1;
+ }
+ }
+ spin_unlock(&c->orphan_lock);
+ return 0;
+}
+
+static int dbg_ins_check_orphan(struct rb_root *root, ino_t inum)
+{
+ struct check_orphan *orphan, *o;
+ struct rb_node **p, *parent = NULL;
+
+ orphan = kzalloc(sizeof(struct check_orphan), GFP_NOFS);
+ if (!orphan)
+ return -ENOMEM;
+ orphan->inum = inum;
+
+ p = &root->rb_node;
+ while (*p) {
+ parent = *p;
+ o = rb_entry(parent, struct check_orphan, rb);
+ if (inum < o->inum)
+ p = &(*p)->rb_left;
+ else if (inum > o->inum)
+ p = &(*p)->rb_right;
+ else {
+ kfree(orphan);
+ return 0;
+ }
+ }
+ rb_link_node(&orphan->rb, parent, p);
+ rb_insert_color(&orphan->rb, root);
+ return 0;
+}
+
+static int dbg_find_check_orphan(struct rb_root *root, ino_t inum)
+{
+ struct check_orphan *o;
+ struct rb_node *p;
+
+ p = root->rb_node;
+ while (p) {
+ o = rb_entry(p, struct check_orphan, rb);
+ if (inum < o->inum)
+ p = p->rb_left;
+ else if (inum > o->inum)
+ p = p->rb_right;
+ else
+ return 1;
+ }
+ return 0;
+}
+
+static void dbg_free_check_tree(struct rb_root *root)
+{
+ struct rb_node *this = root->rb_node;
+ struct check_orphan *o;
+
+ while (this) {
+ if (this->rb_left) {
+ this = this->rb_left;
+ continue;
+ } else if (this->rb_right) {
+ this = this->rb_right;
+ continue;
+ }
+ o = rb_entry(this, struct check_orphan, rb);
+ this = rb_parent(this);
+ if (this) {
+ if (this->rb_left == &o->rb)
+ this->rb_left = NULL;
+ else
+ this->rb_right = NULL;
+ }
+ kfree(o);
+ }
+}
+
+static int dbg_orphan_check(struct ubifs_info *c, struct ubifs_zbranch *zbr,
+ void *priv)
+{
+ struct check_info *ci = priv;
+ ino_t inum;
+ int err;
+
+ inum = key_inum(c, &zbr->key);
+ if (inum != ci->last_ino) {
+ /* Lowest node type is the inode node, so it comes first */
+ if (key_type(c, &zbr->key) != UBIFS_INO_KEY)
+ ubifs_err("found orphan node ino %lu, type %d", inum,
+ key_type(c, &zbr->key));
+ ci->last_ino = inum;
+ ci->tot_inos += 1;
+ err = ubifs_tnc_read_node(c, zbr, ci->node);
+ if (err) {
+ ubifs_err("node read failed, error %d", err);
+ return err;
+ }
+ if (ci->node->nlink == 0)
+ /* Must be recorded as an orphan */
+ if (!dbg_find_check_orphan(&ci->root, inum) &&
+ !dbg_find_orphan(c, inum)) {
+ ubifs_err("missing orphan, ino %lu", inum);
+ ci->missing += 1;
+ }
+ }
+ ci->leaf_cnt += 1;
+ return 0;
+}
+
+static int dbg_read_orphans(struct check_info *ci, struct ubifs_scan_leb *sleb)
+{
+ struct ubifs_scan_node *snod;
+ struct ubifs_orph_node *orph;
+ ino_t inum;
+ int i, n, err;
+
+ list_for_each_entry(snod, &sleb->nodes, list) {
+ cond_resched();
+ if (snod->type != UBIFS_ORPH_NODE)
+ continue;
+ orph = snod->node;
+ n = (le32_to_cpu(orph->ch.len) - UBIFS_ORPH_NODE_SZ) >> 3;
+ for (i = 0; i < n; i++) {
+ inum = le64_to_cpu(orph->inos[i]);
+ err = dbg_ins_check_orphan(&ci->root, inum);
+ if (err)
+ return err;
+ }
+ }
+ return 0;
+}
+
+static int dbg_scan_orphans(struct ubifs_info *c, struct check_info *ci)
+{
+ int lnum, err = 0;
+
+ /* Check no-orphans flag and skip this if no orphans */
+ if (c->no_orphs)
+ return 0;
+
+ for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {
+ struct ubifs_scan_leb *sleb;
+
+ sleb = ubifs_scan(c, lnum, 0, c->dbg_buf);
+ if (IS_ERR(sleb)) {
+ err = PTR_ERR(sleb);
+ break;
+ }
+
+ err = dbg_read_orphans(ci, sleb);
+ ubifs_scan_destroy(sleb);
+ if (err)
+ break;
+ }
+
+ return err;
+}
+
+static int dbg_check_orphans(struct ubifs_info *c)
+{
+ struct check_info ci;
+ int err;
+
+ if (!(ubifs_chk_flags & UBIFS_CHK_ORPH))
+ return 0;
+
+ ci.last_ino = 0;
+ ci.tot_inos = 0;
+ ci.missing = 0;
+ ci.leaf_cnt = 0;
+ ci.root = RB_ROOT;
+ ci.node = kmalloc(UBIFS_MAX_INO_NODE_SZ, GFP_NOFS);
+ if (!ci.node) {
+ ubifs_err("out of memory");
+ return -ENOMEM;
+ }
+
+ err = dbg_scan_orphans(c, &ci);
+ if (err)
+ goto out;
+
+ err = dbg_walk_index(c, &dbg_orphan_check, NULL, &ci);
+ if (err) {
+ ubifs_err("cannot scan TNC, error %d", err);
+ goto out;
+ }
+
+ if (ci.missing) {
+ ubifs_err("%lu missing orphan(s)", ci.missing);
+ err = -EINVAL;
+ goto out;
+ }
+
+ dbg_cmt("last inode number is %lu", ci.last_ino);
+ dbg_cmt("total number of inodes is %lu", ci.tot_inos);
+ dbg_cmt("total number of leaf nodes is %llu", ci.leaf_cnt);
+
+out:
+ dbg_free_check_tree(&ci.root);
+ kfree(ci.node);
+ return err;
+}
+
+#endif /* CONFIG_UBIFS_FS_DEBUG */
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ * Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file implements functions needed to recover from unclean un-mounts.
+ * When UBIFS is mounted, it checks a flag on the master node to determine if
+ * an un-mount was completed sucessfully. If not, the process of mounting
+ * incorparates additional checking and fixing of on-flash data structures.
+ * UBIFS always cleans away all remnants of an unclean un-mount, so that
+ * errors do not accumulate. However UBIFS defers recovery if it is mounted
+ * read-only, and the flash is not modified in that case.
+ */
+
+#include <linux/crc32.h>
+#include "ubifs.h"
+
+/**
+ * is_empty - determine whether a buffer is empty (contains all 0xff).
+ * @buf: buffer to clean
+ * @len: length of buffer
+ *
+ * This function returns %1 if the buffer is empty (contains all 0xff) otherwise
+ * %0 is returned.
+ */
+static int is_empty(void *buf, int len)
+{
+ uint8_t *p = buf;
+ int i;
+
+ for (i = 0; i < len; i++)
+ if (*p++ != 0xff)
+ return 0;
+ return 1;
+}
+
+/**
+ * get_master_node - get the last valid master node allowing for corruption.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number
+ * @pbuf: buffer containing the LEB read, is returned here
+ * @mst: master node, if found, is returned here
+ * @cor: corruption, if found, is returned here
+ *
+ * This function allocates a buffer, reads the LEB into it, and finds and
+ * returns the last valid master node allowing for one area of corruption.
+ * The corrupt area, if there is one, must be consistent with the assumption
+ * that it is the result of an unclean unmount while the master node was being
+ * written. Under those circumstances, it is valid to use the previously written
+ * master node.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int get_master_node(const struct ubifs_info *c, int lnum, void **pbuf,
+ struct ubifs_mst_node **mst, void **cor)
+{
+ const int sz = c->mst_node_alsz;
+ int err, offs, len;
+ void *sbuf, *buf;
+
+ sbuf = vmalloc(c->leb_size);
+ if (!sbuf)
+ return -ENOMEM;
+
+ err = ubi_read(c->ubi, lnum, sbuf, 0, c->leb_size);
+ if (err && err != -EBADMSG)
+ goto out_free;
+
+ /* Find the first position that is definitely not a node */
+ offs = 0;
+ buf = sbuf;
+ len = c->leb_size;
+ while (offs + UBIFS_MST_NODE_SZ <= c->leb_size) {
+ struct ubifs_ch *ch = buf;
+
+ if (le32_to_cpu(ch->magic) != UBIFS_NODE_MAGIC)
+ break;
+ offs += sz;
+ buf += sz;
+ len -= sz;
+ }
+ /* See if there was a valid master node before that */
+ if (offs) {
+ int ret;
+
+ offs -= sz;
+ buf -= sz;
+ len += sz;
+ ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1);
+ if (ret != SCANNED_A_NODE && offs) {
+ /* Could have been corruption so check one place back */
+ offs -= sz;
+ buf -= sz;
+ len += sz;
+ ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1);
+ if (ret != SCANNED_A_NODE)
+ /*
+ * We accept only one area of corruption because
+ * we are assuming that it was caused while
+ * trying to write a master node.
+ */
+ goto out_err;
+ }
+ if (ret == SCANNED_A_NODE) {
+ struct ubifs_ch *ch = buf;
+
+ if (ch->node_type != UBIFS_MST_NODE)
+ goto out_err;
+ dbg_rcvry("found a master node at %d:%d", lnum, offs);
+ *mst = buf;
+ offs += sz;
+ buf += sz;
+ len -= sz;
+ }
+ }
+ /* Check for corruption */
+ if (offs < c->leb_size) {
+ if (!is_empty(buf, min_t(int, len, sz))) {
+ *cor = buf;
+ dbg_rcvry("found corruption at %d:%d", lnum, offs);
+ }
+ offs += sz;
+ buf += sz;
+ len -= sz;
+ }
+ /* Check remaining empty space */
+ if (offs < c->leb_size)
+ if (!is_empty(buf, len))
+ goto out_err;
+ *pbuf = sbuf;
+ return 0;
+
+out_err:
+ err = -EINVAL;
+out_free:
+ vfree(sbuf);
+ *mst = NULL;
+ *cor = NULL;
+ return err;
+}
+
+/**
+ * write_rcvrd_mst_node - write recovered master node.
+ * @c: UBIFS file-system description object
+ * @mst: master node
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int write_rcvrd_mst_node(struct ubifs_info *c,
+ struct ubifs_mst_node *mst)
+{
+ int err = 0, lnum = UBIFS_MST_LNUM, sz = c->mst_node_alsz;
+ uint32_t save_flags;
+
+ dbg_rcvry("recovery");
+
+ save_flags = mst->flags;
+ mst->flags = cpu_to_le32(le32_to_cpu(mst->flags) | UBIFS_MST_RCVRY);
+
+ ubifs_prepare_node(c, mst, UBIFS_MST_NODE_SZ, 1);
+ err = ubi_leb_change(c->ubi, lnum, mst, sz, UBI_SHORTTERM);
+ if (err)
+ goto out;
+ err = ubi_leb_change(c->ubi, lnum + 1, mst, sz, UBI_SHORTTERM);
+ if (err)
+ goto out;
+out:
+ mst->flags = save_flags;
+ return err;
+}
+
+/**
+ * ubifs_recover_master_node - recover the master node.
+ * @c: UBIFS file-system description object
+ *
+ * This function recovers the master node from corruption that may occur due to
+ * an unclean unmount.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_recover_master_node(struct ubifs_info *c)
+{
+ void *buf1 = NULL, *buf2 = NULL, *cor1 = NULL, *cor2 = NULL;
+ struct ubifs_mst_node *mst1 = NULL, *mst2 = NULL, *mst;
+ const int sz = c->mst_node_alsz;
+ int err, offs1, offs2;
+
+ dbg_rcvry("recovery");
+
+ err = get_master_node(c, UBIFS_MST_LNUM, &buf1, &mst1, &cor1);
+ if (err)
+ goto out_free;
+
+ err = get_master_node(c, UBIFS_MST_LNUM + 1, &buf2, &mst2, &cor2);
+ if (err)
+ goto out_free;
+
+ if (mst1) {
+ offs1 = (void *)mst1 - buf1;
+ if ((le32_to_cpu(mst1->flags) & UBIFS_MST_RCVRY) &&
+ (offs1 == 0 && !cor1)) {
+ /*
+ * mst1 was written by recovery at offset 0 with no
+ * corruption.
+ */
+ dbg_rcvry("recovery recovery");
+ mst = mst1;
+ } else if (mst2) {
+ offs2 = (void *)mst2 - buf2;
+ if (offs1 == offs2) {
+ /* Same offset, so must be the same */
+ if (memcmp((void *)mst1 + UBIFS_CH_SZ,
+ (void *)mst2 + UBIFS_CH_SZ,
+ UBIFS_MST_NODE_SZ - UBIFS_CH_SZ))
+ goto out_err;
+ mst = mst1;
+ } else if (offs2 + sz == offs1) {
+ /* 1st LEB was written, 2nd was not */
+ if (cor1)
+ goto out_err;
+ mst = mst1;
+ } else if (offs1 == 0 && offs2 + sz >= c->leb_size) {
+ /* 1st LEB was unmapped and written, 2nd not */
+ if (cor1)
+ goto out_err;
+ mst = mst1;
+ } else
+ goto out_err;
+ } else {
+ /*
+ * 2nd LEB was unmapped and about to be written, so
+ * there must be only one master node in the first LEB
+ * and no corruption.
+ */
+ if (offs1 != 0 || cor1)
+ goto out_err;
+ mst = mst1;
+ }
+ } else {
+ if (!mst2)
+ goto out_err;
+ /*
+ * 1st LEB was unmapped and about to be written, so there must
+ * be no room left in 2nd LEB.
+ */
+ offs2 = (void *)mst2 - buf2;
+ if (offs2 + sz + sz <= c->leb_size)
+ goto out_err;
+ mst = mst2;
+ }
+
+ dbg_rcvry("recovered master node from LEB %d",
+ (mst == mst1 ? UBIFS_MST_LNUM : UBIFS_MST_LNUM + 1));
+
+ memcpy(c->mst_node, mst, UBIFS_MST_NODE_SZ);
+
+ if ((c->vfs_sb->s_flags & MS_RDONLY)) {
+ /* Read-only mode. Keep a copy for switching to rw mode */
+ c->rcvrd_mst_node = kmalloc(sz, GFP_KERNEL);
+ if (!c->rcvrd_mst_node) {
+ err = -ENOMEM;
+ goto out_free;
+ }
+ memcpy(c->rcvrd_mst_node, c->mst_node, UBIFS_MST_NODE_SZ);
+ } else {
+ /* Write the recovered master node */
+ c->max_sqnum = le64_to_cpu(mst->ch.sqnum) - 1;
+ err = write_rcvrd_mst_node(c, c->mst_node);
+ if (err)
+ goto out_free;
+ }
+
+ vfree(buf2);
+ vfree(buf1);
+
+ return 0;
+
+out_err:
+ err = -EINVAL;
+out_free:
+ ubifs_err("failed to recover master node");
+ if (mst1) {
+ dbg_err("dumping first master node");
+ dbg_dump_node(c, mst1);
+ }
+ if (mst2) {
+ dbg_err("dumping second master node");
+ dbg_dump_node(c, mst2);
+ }
+ vfree(buf2);
+ vfree(buf1);
+ return err;
+}
+
+/**
+ * ubifs_write_rcvrd_mst_node - write the recovered master node.
+ * @c: UBIFS file-system description object
+ *
+ * This function writes the master node that was recovered during mounting in
+ * read-only mode and must now be written because we are remounting rw.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_write_rcvrd_mst_node(struct ubifs_info *c)
+{
+ int err;
+
+ if (!c->rcvrd_mst_node)
+ return 0;
+ c->rcvrd_mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
+ c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
+ err = write_rcvrd_mst_node(c, c->rcvrd_mst_node);
+ if (err)
+ return err;
+ kfree(c->rcvrd_mst_node);
+ c->rcvrd_mst_node = NULL;
+ return 0;
+}
+
+/**
+ * is_last_write - determine if an offset was in the last write to a LEB.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to check
+ * @offs: offset to check
+ *
+ * This function returns %1 if @offs was in the last write to the LEB whose data
+ * is in @buf, otherwise %0 is returned. The determination is made by checking
+ * for subsequent empty space starting from the next min_io_size boundary (or a
+ * bit less than the common header size if min_io_size is one).
+ */
+static int is_last_write(const struct ubifs_info *c, void *buf, int offs)
+{
+ int empty_offs;
+ int check_len;
+ uint8_t *p;
+
+ if (c->min_io_size == 1) {
+ check_len = c->leb_size - offs;
+ p = buf + check_len;
+ for (; check_len > 0; check_len--)
+ if (*--p != 0xff)
+ break;
+ /*
+ * 'check_len' is the size of the corruption which cannot be
+ * more than the size of 1 node if it was caused by an unclean
+ * unmount.
+ */
+ if (check_len > UBIFS_MAX_NODE_SZ)
+ return 0;
+ return 1;
+ }
+
+ /*
+ * Round up to the next c->min_io_size boundary i.e. 'offs' is in the
+ * last wbuf written. After that should be empty space.
+ */
+ empty_offs = ALIGN(offs + 1, c->min_io_size);
+ check_len = c->leb_size - empty_offs;
+ p = buf + empty_offs - offs;
+
+ for (; check_len > 0; check_len--)
+ if (*p++ != 0xff)
+ return 0;
+ return 1;
+}
+
+/**
+ * clean_buf - clean the data from an LEB sitting in a buffer.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to clean
+ * @lnum: LEB number to clean
+ * @offs: offset from which to clean
+ * @len: length of buffer
+ *
+ * This function pads up to the next min_io_size boundary (if there is one) and
+ * sets empty space to all 0xff. @buf, @offs and @len are updated to the next
+ * min_io_size boundary (if there is one).
+ */
+static void clean_buf(const struct ubifs_info *c, void **buf, int lnum,
+ int *offs, int *len)
+{
+ int empty_offs, pad_len;
+
+ lnum = lnum;
+ dbg_rcvry("cleaning corruption at %d:%d", lnum, *offs);
+
+ if (c->min_io_size == 1) {
+ memset(*buf, 0xff, c->leb_size - *offs);
+ return;
+ }
+
+ ubifs_assert(!(*offs & 7));
+ empty_offs = ALIGN(*offs, c->min_io_size);
+ pad_len = empty_offs - *offs;
+ ubifs_pad(c, *buf, pad_len);
+ *offs += pad_len;
+ *buf += pad_len;
+ *len -= pad_len;
+ memset(*buf, 0xff, c->leb_size - empty_offs);
+}
+
+/**
+ * no_more_nodes - determine if there are no more nodes in a buffer.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to check
+ * @len: length of buffer
+ * @lnum: LEB number of the LEB from which @buf was read
+ * @offs: offset from which @buf was read
+ *
+ * This function scans @buf for more nodes and returns %0 is a node is found and
+ * %1 if no more nodes are found.
+ */
+static int no_more_nodes(const struct ubifs_info *c, void *buf, int len,
+ int lnum, int offs)
+{
+ int skip, next_offs = 0;
+
+ if (len > UBIFS_DATA_NODE_SZ) {
+ struct ubifs_ch *ch = buf;
+ int dlen = le32_to_cpu(ch->len);
+
+ if (ch->node_type == UBIFS_DATA_NODE && dlen >= UBIFS_CH_SZ &&
+ dlen <= UBIFS_MAX_DATA_NODE_SZ)
+ /* The corrupt node looks like a data node */
+ next_offs = ALIGN(offs + dlen, 8);
+ }
+
+ if (c->min_io_size == 1)
+ skip = 8;
+ else
+ skip = ALIGN(offs + 1, c->min_io_size) - offs;
+
+ offs += skip;
+ buf += skip;
+ len -= skip;
+ while (len > 8) {
+ struct ubifs_ch *ch = buf;
+ uint32_t magic = le32_to_cpu(ch->magic);
+ int ret;
+
+ if (magic == UBIFS_NODE_MAGIC) {
+ ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1);
+ if (ret == SCANNED_A_NODE || ret > 0) {
+ /*
+ * There is a small chance this is just data in
+ * a data node, so check that possibility. e.g.
+ * this is part of a file that itself contains
+ * a UBIFS image.
+ */
+ if (next_offs && offs + le32_to_cpu(ch->len) <=
+ next_offs)
+ continue;
+ dbg_rcvry("unexpected node at %d:%d", lnum,
+ offs);
+ return 0;
+ }
+ }
+ offs += 8;
+ buf += 8;
+ len -= 8;
+ }
+ return 1;
+}
+
+/**
+ * fix_unclean_leb - fix an unclean LEB.
+ * @c: UBIFS file-system description object
+ * @sleb: scanned LEB information
+ * @start: offset where scan started
+ */
+static int fix_unclean_leb(struct ubifs_info *c, struct ubifs_scan_leb *sleb,
+ int start)
+{
+ int lnum = sleb->lnum, endpt = start;
+
+ /* Get the end offset of the last node we are keeping */
+ if (!list_empty(&sleb->nodes)) {
+ struct ubifs_scan_node *snod;
+
+ snod = list_entry(sleb->nodes.prev,
+ struct ubifs_scan_node, list);
+ endpt = snod->offs + snod->len;
+ }
+
+ if ((c->vfs_sb->s_flags & MS_RDONLY) && !c->remounting_rw) {
+ /* Add to recovery list */
+ struct ubifs_unclean_leb *ucleb;
+
+ dbg_rcvry("need to fix LEB %d start %d endpt %d",
+ lnum, start, sleb->endpt);
+ ucleb = kzalloc(sizeof(struct ubifs_unclean_leb), GFP_NOFS);
+ if (!ucleb)
+ return -ENOMEM;
+ ucleb->lnum = lnum;
+ ucleb->endpt = endpt;
+ list_add_tail(&ucleb->list, &c->unclean_leb_list);
+ } else {
+ /* Write the fixed LEB back to flash */
+ int err;
+
+ dbg_rcvry("fixing LEB %d start %d endpt %d",
+ lnum, start, sleb->endpt);
+ if (endpt == 0) {
+ err = ubifs_leb_unmap(c, lnum);
+ if (err)
+ return err;
+ } else {
+ int len = ALIGN(endpt, c->min_io_size);
+
+ if (start) {
+ err = ubi_read(c->ubi, lnum, sleb->buf, 0,
+ start);
+ if (err)
+ return err;
+ }
+ /* Pad to min_io_size */
+ if (len > endpt) {
+ int pad_len = len - ALIGN(endpt, 8);
+
+ if (pad_len > 0) {
+ void *buf = sleb->buf + len - pad_len;
+
+ ubifs_pad(c, buf, pad_len);
+ }
+ }
+ err = ubi_leb_change(c->ubi, lnum, sleb->buf, len,
+ UBI_UNKNOWN);
+ if (err)
+ return err;
+ }
+ }
+ return 0;
+}
+
+/**
+ * drop_incomplete_group - drop nodes from an incomplete group.
+ * @sleb: scanned LEB information
+ * @offs: offset of dropped nodes is returned here
+ *
+ * This function returns %1 if nodes are dropped and %0 otherwise.
+ */
+static int drop_incomplete_group(struct ubifs_scan_leb *sleb, int *offs)
+{
+ int dropped = 0;
+
+ while (!list_empty(&sleb->nodes)) {
+ struct ubifs_scan_node *snod;
+ struct ubifs_ch *ch;
+
+ snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node,
+ list);
+ ch = snod->node;
+ if (ch->group_type != UBIFS_IN_NODE_GROUP)
+ return dropped;
+ dbg_rcvry("dropping node at %d:%d", sleb->lnum, snod->offs);
+ *offs = snod->offs;
+ list_del(&snod->list);
+ kfree(snod);
+ sleb->nodes_cnt -= 1;
+ dropped = 1;
+ }
+ return dropped;
+}
+
+/**
+ * ubifs_recover_leb - scan and recover a LEB.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number
+ * @offs: offset
+ * @sbuf: LEB-sized buffer to use
+ * @grouped: nodes may be grouped for recovery
+ *
+ * This function does a scan of a LEB, but caters for errors that might have
+ * been caused by the unclean unmount from which we are attempting to recover.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum,
+ int offs, void *sbuf, int grouped)
+{
+ int err, len = c->leb_size - offs, need_clean = 0, quiet = 1;
+ int empty_chkd = 0, start = offs;
+ struct ubifs_scan_leb *sleb;
+ void *buf = sbuf + offs;
+
+ dbg_rcvry("%d:%d", lnum, offs);
+
+ sleb = ubifs_start_scan(c, lnum, offs, sbuf);
+ if (IS_ERR(sleb))
+ return sleb;
+
+ if (sleb->ecc)
+ need_clean = 1;
+
+ while (len >= 8) {
+ int ret;
+
+ dbg_scan("look at LEB %d:%d (%d bytes left)",
+ lnum, offs, len);
+
+ cond_resched();
+
+ /*
+ * Scan quietly until there is an error from which we cannot
+ * recover
+ */
+ ret = ubifs_scan_a_node(c, buf, len, lnum, offs, quiet);
+
+ if (ret == SCANNED_A_NODE) {
+ /* A valid node, and not a padding node */
+ struct ubifs_ch *ch = buf;
+ int node_len;
+
+ err = ubifs_add_snod(c, sleb, buf, offs);
+ if (err)
+ goto error;
+ node_len = ALIGN(le32_to_cpu(ch->len), 8);
+ offs += node_len;
+ buf += node_len;
+ len -= node_len;
+ continue;
+ }
+
+ if (ret > 0) {
+ /* Padding bytes or a valid padding node */
+ offs += ret;
+ buf += ret;
+ len -= ret;
+ continue;
+ }
+
+ if (ret == SCANNED_EMPTY_SPACE) {
+ if (!is_empty(buf, len)) {
+ if (!is_last_write(c, buf, offs))
+ break;
+ clean_buf(c, &buf, lnum, &offs, &len);
+ need_clean = 1;
+ }
+ empty_chkd = 1;
+ break;
+ }
+
+ if (ret == SCANNED_GARBAGE || ret == SCANNED_A_BAD_PAD_NODE)
+ if (is_last_write(c, buf, offs)) {
+ clean_buf(c, &buf, lnum, &offs, &len);
+ need_clean = 1;
+ empty_chkd = 1;
+ break;
+ }
+
+ if (ret == SCANNED_A_CORRUPT_NODE)
+ if (no_more_nodes(c, buf, len, lnum, offs)) {
+ clean_buf(c, &buf, lnum, &offs, &len);
+ need_clean = 1;
+ empty_chkd = 1;
+ break;
+ }
+
+ if (quiet) {
+ /* Redo the last scan but noisily */
+ quiet = 0;
+ continue;
+ }
+
+ switch (ret) {
+ case SCANNED_GARBAGE:
+ dbg_err("garbage");
+ goto corrupted;
+ case SCANNED_A_CORRUPT_NODE:
+ case SCANNED_A_BAD_PAD_NODE:
+ dbg_err("bad node");
+ goto corrupted;
+ default:
+ dbg_err("unknown");
+ goto corrupted;
+ }
+ }
+
+ if (!empty_chkd && !is_empty(buf, len)) {
+ if (is_last_write(c, buf, offs)) {
+ clean_buf(c, &buf, lnum, &offs, &len);
+ need_clean = 1;
+ } else {
+ ubifs_err("corrupt empty space at LEB %d:%d",
+ lnum, offs);
+ goto corrupted;
+ }
+ }
+
+ /* Drop nodes from incomplete group */
+ if (grouped && drop_incomplete_group(sleb, &offs)) {
+ buf = sbuf + offs;
+ len = c->leb_size - offs;
+ clean_buf(c, &buf, lnum, &offs, &len);
+ need_clean = 1;
+ }
+
+ if (offs % c->min_io_size) {
+ clean_buf(c, &buf, lnum, &offs, &len);
+ need_clean = 1;
+ }
+
+ ubifs_end_scan(c, sleb, lnum, offs);
+
+ if (need_clean) {
+ err = fix_unclean_leb(c, sleb, start);
+ if (err)
+ goto error;
+ }
+
+ return sleb;
+
+corrupted:
+ ubifs_scanned_corruption(c, lnum, offs, buf);
+ err = -EUCLEAN;
+error:
+ ubifs_err("LEB %d scanning failed", lnum);
+ ubifs_scan_destroy(sleb);
+ return ERR_PTR(err);
+}
+
+/**
+ * get_cs_sqnum - get commit start sequence number.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number of commit start node
+ * @offs: offset of commit start node
+ * @cs_sqnum: commit start sequence number is returned here
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int get_cs_sqnum(struct ubifs_info *c, int lnum, int offs,
+ unsigned long long *cs_sqnum)
+{
+ struct ubifs_cs_node *cs_node = NULL;
+ int err, ret;
+
+ dbg_rcvry("at %d:%d", lnum, offs);
+ cs_node = kmalloc(UBIFS_CS_NODE_SZ, GFP_KERNEL);
+ if (!cs_node)
+ return -ENOMEM;
+ if (c->leb_size - offs < UBIFS_CS_NODE_SZ)
+ goto out_err;
+ err = ubi_read(c->ubi, lnum, (void *)cs_node, offs, UBIFS_CS_NODE_SZ);
+ if (err && err != -EBADMSG)
+ goto out_free;
+ ret = ubifs_scan_a_node(c, cs_node, UBIFS_CS_NODE_SZ, lnum, offs, 0);
+ if (ret != SCANNED_A_NODE) {
+ dbg_err("Not a valid node");
+ goto out_err;
+ }
+ if (cs_node->ch.node_type != UBIFS_CS_NODE) {
+ dbg_err("Node a CS node, type is %d", cs_node->ch.node_type);
+ goto out_err;
+ }
+ if (le64_to_cpu(cs_node->cmt_no) != c->cmt_no) {
+ dbg_err("CS node cmt_no %llu != current cmt_no %llu",
+ (unsigned long long)le64_to_cpu(cs_node->cmt_no),
+ c->cmt_no);
+ goto out_err;
+ }
+ *cs_sqnum = le64_to_cpu(cs_node->ch.sqnum);
+ dbg_rcvry("commit start sqnum %llu", *cs_sqnum);
+ kfree(cs_node);
+ return 0;
+
+out_err:
+ err = -EINVAL;
+out_free:
+ ubifs_err("failed to get CS sqnum");
+ kfree(cs_node);
+ return err;
+}
+
+/**
+ * ubifs_recover_log_leb - scan and recover a log LEB.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number
+ * @offs: offset
+ * @sbuf: LEB-sized buffer to use
+ *
+ * This function does a scan of a LEB, but caters for errors that might have
+ * been caused by the unclean unmount from which we are attempting to recover.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+struct ubifs_scan_leb *ubifs_recover_log_leb(struct ubifs_info *c, int lnum,
+ int offs, void *sbuf)
+{
+ struct ubifs_scan_leb *sleb;
+ int next_lnum;
+
+ dbg_rcvry("LEB %d", lnum);
+ next_lnum = lnum + 1;
+ if (next_lnum >= UBIFS_LOG_LNUM + c->log_lebs)
+ next_lnum = UBIFS_LOG_LNUM;
+ if (next_lnum != c->ltail_lnum) {
+ /*
+ * We can only recover at the end of the log, so check that the
+ * next log LEB is empty or out of date.
+ */
+ sleb = ubifs_scan(c, next_lnum, 0, sbuf);
+ if (IS_ERR(sleb))
+ return sleb;
+ if (sleb->nodes_cnt) {
+ struct ubifs_scan_node *snod;
+ unsigned long long cs_sqnum = c->cs_sqnum;
+
+ snod = list_entry(sleb->nodes.next,
+ struct ubifs_scan_node, list);
+ if (cs_sqnum == 0) {
+ int err;
+
+ err = get_cs_sqnum(c, lnum, offs, &cs_sqnum);
+ if (err) {
+ ubifs_scan_destroy(sleb);
+ return ERR_PTR(err);
+ }
+ }
+ if (snod->sqnum > cs_sqnum) {
+ ubifs_err("unrecoverable log corruption "
+ "in LEB %d", lnum);
+ ubifs_scan_destroy(sleb);
+ return ERR_PTR(-EUCLEAN);
+ }
+ }
+ ubifs_scan_destroy(sleb);
+ }
+ return ubifs_recover_leb(c, lnum, offs, sbuf, 0);
+}
+
+/**
+ * recover_head - recover a head.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number of head to recover
+ * @offs: offset of head to recover
+ * @sbuf: LEB-sized buffer to use
+ *
+ * This function ensures that there is no data on the flash at a head location.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int recover_head(const struct ubifs_info *c, int lnum, int offs,
+ void *sbuf)
+{
+ int len, err, need_clean = 0;
+
+ if (c->min_io_size > 1)
+ len = c->min_io_size;
+ else
+ len = 512;
+ if (offs + len > c->leb_size)
+ len = c->leb_size - offs;
+
+ if (!len)
+ return 0;
+
+ /* Read at the head location and check it is empty flash */
+ err = ubi_read(c->ubi, lnum, sbuf, offs, len);
+ if (err)
+ need_clean = 1;
+ else {
+ uint8_t *p = sbuf;
+
+ while (len--)
+ if (*p++ != 0xff) {
+ need_clean = 1;
+ break;
+ }
+ }
+
+ if (need_clean) {
+ dbg_rcvry("cleaning head at %d:%d", lnum, offs);
+ if (offs == 0)
+ return ubifs_leb_unmap(c, lnum);
+ err = ubi_read(c->ubi, lnum, sbuf, 0, offs);
+ if (err)
+ return err;
+ return ubi_leb_change(c->ubi, lnum, sbuf, offs, UBI_UNKNOWN);
+ }
+
+ return 0;
+}
+
+/**
+ * ubifs_recover_inl_heads - recover index and LPT heads.
+ * @c: UBIFS file-system description object
+ * @sbuf: LEB-sized buffer to use
+ *
+ * This function ensures that there is no data on the flash at the index and
+ * LPT head locations.
+ *
+ * This deals with the recovery of a half-completed journal commit. UBIFS is
+ * careful never to overwrite the last version of the index or the LPT. Because
+ * the index and LPT are wandering trees, data from a half-completed commit will
+ * not be referenced anywhere in UBIFS. The data will be either in LEBs that are
+ * assumed to be empty and will be unmapped anyway before use, or in the index
+ * and LPT heads.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_recover_inl_heads(const struct ubifs_info *c, void *sbuf)
+{
+ int err;
+
+ ubifs_assert(!(c->vfs_sb->s_flags & MS_RDONLY) || c->remounting_rw);
+
+ dbg_rcvry("checking index head at %d:%d", c->ihead_lnum, c->ihead_offs);
+ err = recover_head(c, c->ihead_lnum, c->ihead_offs, sbuf);
+ if (err)
+ return err;
+
+ dbg_rcvry("checking LPT head at %d:%d", c->nhead_lnum, c->nhead_offs);
+ err = recover_head(c, c->nhead_lnum, c->nhead_offs, sbuf);
+ if (err)
+ return err;
+
+ return 0;
+}
+
+/**
+ * clean_an_unclean_leb - read and write a LEB to remove corruption.
+ * @c: UBIFS file-system description object
+ * @ucleb: unclean LEB information
+ * @sbuf: LEB-sized buffer to use
+ *
+ * This function reads a LEB up to a point pre-determined by the mount recovery,
+ * checks the nodes, and writes the result back to the flash, thereby cleaning
+ * off any following corruption, or non-fatal ECC errors.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int clean_an_unclean_leb(const struct ubifs_info *c,
+ struct ubifs_unclean_leb *ucleb, void *sbuf)
+{
+ int err, lnum = ucleb->lnum, offs = 0, len = ucleb->endpt, quiet = 1;
+ void *buf = sbuf;
+
+ dbg_rcvry("LEB %d len %d", lnum, len);
+
+ if (len == 0) {
+ /* Nothing to read, just unmap it */
+ err = ubifs_leb_unmap(c, lnum);
+ if (err)
+ return err;
+ return 0;
+ }
+
+ err = ubi_read(c->ubi, lnum, buf, offs, len);
+ if (err && err != -EBADMSG)
+ return err;
+
+ while (len >= 8) {
+ int ret;
+
+ cond_resched();
+
+ /* Scan quietly until there is an error */
+ ret = ubifs_scan_a_node(c, buf, len, lnum, offs, quiet);
+
+ if (ret == SCANNED_A_NODE) {
+ /* A valid node, and not a padding node */
+ struct ubifs_ch *ch = buf;
+ int node_len;
+
+ node_len = ALIGN(le32_to_cpu(ch->len), 8);
+ offs += node_len;
+ buf += node_len;
+ len -= node_len;
+ continue;
+ }
+
+ if (ret > 0) {
+ /* Padding bytes or a valid padding node */
+ offs += ret;
+ buf += ret;
+ len -= ret;
+ continue;
+ }
+
+ if (ret == SCANNED_EMPTY_SPACE) {
+ ubifs_err("unexpected empty space at %d:%d",
+ lnum, offs);
+ return -EUCLEAN;
+ }
+
+ if (quiet) {
+ /* Redo the last scan but noisily */
+ quiet = 0;
+ continue;
+ }
+
+ ubifs_scanned_corruption(c, lnum, offs, buf);
+ return -EUCLEAN;
+ }
+
+ /* Pad to min_io_size */
+ len = ALIGN(ucleb->endpt, c->min_io_size);
+ if (len > ucleb->endpt) {
+ int pad_len = len - ALIGN(ucleb->endpt, 8);
+
+ if (pad_len > 0) {
+ buf = c->sbuf + len - pad_len;
+ ubifs_pad(c, buf, pad_len);
+ }
+ }
+
+ /* Write back the LEB atomically */
+ err = ubi_leb_change(c->ubi, lnum, sbuf, len, UBI_UNKNOWN);
+ if (err)
+ return err;
+
+ dbg_rcvry("cleaned LEB %d", lnum);
+
+ return 0;
+}
+
+/**
+ * ubifs_clean_lebs - clean LEBs recovered during read-only mount.
+ * @c: UBIFS file-system description object
+ * @sbuf: LEB-sized buffer to use
+ *
+ * This function cleans a LEB identified during recovery that needs to be
+ * written but was not because UBIFS was mounted read-only. This happens when
+ * remounting to read-write mode.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_clean_lebs(const struct ubifs_info *c, void *sbuf)
+{
+ dbg_rcvry("recovery");
+ while (!list_empty(&c->unclean_leb_list)) {
+ struct ubifs_unclean_leb *ucleb;
+ int err;
+
+ ucleb = list_entry(c->unclean_leb_list.next,
+ struct ubifs_unclean_leb, list);
+ err = clean_an_unclean_leb(c, ucleb, sbuf);
+ if (err)
+ return err;
+ list_del(&ucleb->list);
+ kfree(ucleb);
+ }
+ return 0;
+}
+
+/**
+ * ubifs_rcvry_gc_commit - recover the GC LEB number and run the commit.
+ * @c: UBIFS file-system description object
+ *
+ * Out-of-place garbage collection requires always one empty LEB with which to
+ * start garbage collection. The LEB number is recorded in c->gc_lnum and is
+ * written to the master node on unmounting. In the case of an unclean unmount
+ * the value of gc_lnum recorded in the master node is out of date and cannot
+ * be used. Instead, recovery must allocate an empty LEB for this purpose.
+ * However, there may not be enough empty space, in which case it must be
+ * possible to GC the dirtiest LEB into the GC head LEB.
+ *
+ * This function also runs the commit which causes the TNC updates from
+ * size-recovery and orphans to be written to the flash. That is important to
+ * ensure correct replay order for subsequent mounts.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_rcvry_gc_commit(struct ubifs_info *c)
+{
+ struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf;
+ struct ubifs_lprops lp;
+ int lnum, err;
+
+ c->gc_lnum = -1;
+ if (wbuf->lnum == -1) {
+ dbg_rcvry("no GC head LEB");
+ goto find_free;
+ }
+ /*
+ * See whether the used space in the dirtiest LEB fits in the GC head
+ * LEB.
+ */
+ if (wbuf->offs == c->leb_size) {
+ dbg_rcvry("no room in GC head LEB");
+ goto find_free;
+ }
+ err = ubifs_find_dirty_leb(c, &lp, wbuf->offs, 2);
+ if (err) {
+ if (err == -ENOSPC)
+ dbg_err("could not find a dirty LEB");
+ return err;
+ }
+ ubifs_assert(!(lp.flags & LPROPS_INDEX));
+ lnum = lp.lnum;
+ if (lp.free + lp.dirty == c->leb_size) {
+ /* An empty LEB was returned */
+ if (lp.free != c->leb_size) {
+ err = ubifs_change_one_lp(c, lnum, c->leb_size,
+ 0, 0, 0, 0);
+ if (err)
+ return err;
+ }
+ err = ubifs_leb_unmap(c, lnum);
+ if (err)
+ return err;
+ c->gc_lnum = lnum;
+ dbg_rcvry("allocated LEB %d for GC", lnum);
+ /* Run the commit */
+ dbg_rcvry("committing");
+ return ubifs_run_commit(c);
+ }
+ /*
+ * There was no empty LEB so the used space in the dirtiest LEB must fit
+ * in the GC head LEB.
+ */
+ if (lp.free + lp.dirty < wbuf->offs) {
+ dbg_rcvry("LEB %d doesn't fit in GC head LEB %d:%d",
+ lnum, wbuf->lnum, wbuf->offs);
+ err = ubifs_return_leb(c, lnum);
+ if (err)
+ return err;
+ goto find_free;
+ }
+ /*
+ * We run the commit before garbage collection otherwise subsequent
+ * mounts will see the GC and orphan deletion in a different order.
+ */
+ dbg_rcvry("committing");
+ err = ubifs_run_commit(c);
+ if (err)
+ return err;
+ /*
+ * The data in the dirtiest LEB fits in the GC head LEB, so do the GC
+ * - use locking to keep 'ubifs_assert()' happy.
+ */
+ dbg_rcvry("GC'ing LEB %d", lnum);
+ mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
+ err = ubifs_garbage_collect_leb(c, &lp);
+ if (err >= 0) {
+ int err2 = ubifs_wbuf_sync_nolock(wbuf);
+
+ if (err2)
+ err = err2;
+ }
+ mutex_unlock(&wbuf->io_mutex);
+ if (err < 0) {
+ dbg_err("GC failed, error %d", err);
+ if (err == -EAGAIN)
+ err = -EINVAL;
+ return err;
+ }
+ if (err != LEB_RETAINED) {
+ dbg_err("GC returned %d", err);
+ return -EINVAL;
+ }
+ err = ubifs_leb_unmap(c, c->gc_lnum);
+ if (err)
+ return err;
+ dbg_rcvry("allocated LEB %d for GC", lnum);
+ return 0;
+
+find_free:
+ /*
+ * There is no GC head LEB or the free space in the GC head LEB is too
+ * small. Allocate gc_lnum by calling 'ubifs_find_free_leb_for_idx()' so
+ * GC is not run.
+ */
+ lnum = ubifs_find_free_leb_for_idx(c);
+ if (lnum < 0) {
+ dbg_err("could not find an empty LEB");
+ return lnum;
+ }
+ /* And reset the index flag */
+ err = ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0,
+ LPROPS_INDEX, 0);
+ if (err)
+ return err;
+ c->gc_lnum = lnum;
+ dbg_rcvry("allocated LEB %d for GC", lnum);
+ /* Run the commit */
+ dbg_rcvry("committing");
+ return ubifs_run_commit(c);
+}
+
+/**
+ * struct size_entry - inode size information for recovery.
+ * @rb: link in the RB-tree of sizes
+ * @inum: inode number
+ * @i_size: size on inode
+ * @d_size: maximum size based on data nodes
+ * @exists: indicates whether the inode exists
+ * @inode: inode if pinned in memory awaiting rw mode to fix it
+ */
+struct size_entry {
+ struct rb_node rb;
+ ino_t inum;
+ loff_t i_size;
+ loff_t d_size;
+ int exists;
+ struct inode *inode;
+};
+
+/**
+ * add_ino - add an entry to the size tree.
+ * @c: UBIFS file-system description object
+ * @inum: inode number
+ * @i_size: size on inode
+ * @d_size: maximum size based on data nodes
+ * @exists: indicates whether the inode exists
+ */
+static int add_ino(struct ubifs_info *c, ino_t inum, loff_t i_size,
+ loff_t d_size, int exists)
+{
+ struct rb_node **p = &c->size_tree.rb_node, *parent = NULL;
+ struct size_entry *e;
+
+ while (*p) {
+ parent = *p;
+ e = rb_entry(parent, struct size_entry, rb);
+ if (inum < e->inum)
+ p = &(*p)->rb_left;
+ else
+ p = &(*p)->rb_right;
+ }
+
+ e = kzalloc(sizeof(struct size_entry), GFP_KERNEL);
+ if (!e)
+ return -ENOMEM;
+
+ e->inum = inum;
+ e->i_size = i_size;
+ e->d_size = d_size;
+ e->exists = exists;
+
+ rb_link_node(&e->rb, parent, p);
+ rb_insert_color(&e->rb, &c->size_tree);
+
+ return 0;
+}
+
+/**
+ * find_ino - find an entry on the size tree.
+ * @c: UBIFS file-system description object
+ * @inum: inode number
+ */
+static struct size_entry *find_ino(struct ubifs_info *c, ino_t inum)
+{
+ struct rb_node *p = c->size_tree.rb_node;
+ struct size_entry *e;
+
+ while (p) {
+ e = rb_entry(p, struct size_entry, rb);
+ if (inum < e->inum)
+ p = p->rb_left;
+ else if (inum > e->inum)
+ p = p->rb_right;
+ else
+ return e;
+ }
+ return NULL;
+}
+
+/**
+ * remove_ino - remove an entry from the size tree.
+ * @c: UBIFS file-system description object
+ * @inum: inode number
+ */
+static void remove_ino(struct ubifs_info *c, ino_t inum)
+{
+ struct size_entry *e = find_ino(c, inum);
+
+ if (!e)
+ return;
+ rb_erase(&e->rb, &c->size_tree);
+ kfree(e);
+}
+
+/**
+ * ubifs_destroy_size_tree - free resources related to the size tree.
+ * @c: UBIFS file-system description object
+ */
+void ubifs_destroy_size_tree(struct ubifs_info *c)
+{
+ struct rb_node *this = c->size_tree.rb_node;
+ struct size_entry *e;
+
+ while (this) {
+ if (this->rb_left) {
+ this = this->rb_left;
+ continue;
+ } else if (this->rb_right) {
+ this = this->rb_right;
+ continue;
+ }
+ e = rb_entry(this, struct size_entry, rb);
+ if (e->inode)
+ iput(e->inode);
+ this = rb_parent(this);
+ if (this) {
+ if (this->rb_left == &e->rb)
+ this->rb_left = NULL;
+ else
+ this->rb_right = NULL;
+ }
+ kfree(e);
+ }
+ c->size_tree = RB_ROOT;
+}
+
+/**
+ * ubifs_recover_size_accum - accumulate inode sizes for recovery.
+ * @c: UBIFS file-system description object
+ * @key: node key
+ * @deletion: node is for a deletion
+ * @new_size: inode size
+ *
+ * This function has two purposes:
+ * 1) to ensure there are no data nodes that fall outside the inode size
+ * 2) to ensure there are no data nodes for inodes that do not exist
+ * To accomplish those purposes, a rb-tree is constructed containing an entry
+ * for each inode number in the journal that has not been deleted, and recording
+ * the size from the inode node, the maximum size of any data node (also altered
+ * by truncations) and a flag indicating a inode number for which no inode node
+ * was present in the journal.
+ *
+ * Note that there is still the possibility that there are data nodes that have
+ * been committed that are beyond the inode size, however the only way to find
+ * them would be to scan the entire index. Alternatively, some provision could
+ * be made to record the size of inodes at the start of commit, which would seem
+ * very cumbersome for a scenario that is quite unlikely and the only negative
+ * consequence of which is wasted space.
+ *
+ * This functions returns %0 on success and a negative error code on failure.
+ */
+int ubifs_recover_size_accum(struct ubifs_info *c, union ubifs_key *key,
+ int deletion, loff_t new_size)
+{
+ ino_t inum = key_inum(c, key);
+ struct size_entry *e;
+ int err;
+
+ switch (key_type(c, key)) {
+ case UBIFS_INO_KEY:
+ if (deletion)
+ remove_ino(c, inum);
+ else {
+ e = find_ino(c, inum);
+ if (e) {
+ e->i_size = new_size;
+ e->exists = 1;
+ } else {
+ err = add_ino(c, inum, new_size, 0, 1);
+ if (err)
+ return err;
+ }
+ }
+ break;
+ case UBIFS_DATA_KEY:
+ e = find_ino(c, inum);
+ if (e) {
+ if (new_size > e->d_size)
+ e->d_size = new_size;
+ } else {
+ err = add_ino(c, inum, 0, new_size, 0);
+ if (err)
+ return err;
+ }
+ break;
+ case UBIFS_TRUN_KEY:
+ e = find_ino(c, inum);
+ if (e)
+ e->d_size = new_size;
+ break;
+ }
+ return 0;
+}
+
+/**
+ * fix_size_in_place - fix inode size in place on flash.
+ * @c: UBIFS file-system description object
+ * @e: inode size information for recovery
+ */
+static int fix_size_in_place(struct ubifs_info *c, struct size_entry *e)
+{
+ struct ubifs_ino_node *ino = c->sbuf;
+ unsigned char *p;
+ union ubifs_key key;
+ int err, lnum, offs, len;
+ loff_t i_size;
+ uint32_t crc;
+
+ /* Locate the inode node LEB number and offset */
+ ino_key_init(c, &key, e->inum);
+ err = ubifs_tnc_locate(c, &key, ino, &lnum, &offs);
+ if (err)
+ goto out;
+ /*
+ * If the size recorded on the inode node is greater than the size that
+ * was calculated from nodes in the journal then don't change the inode.
+ */
+ i_size = le64_to_cpu(ino->size);
+ if (i_size >= e->d_size)
+ return 0;
+ /* Read the LEB */
+ err = ubi_read(c->ubi, lnum, c->sbuf, 0, c->leb_size);
+ if (err)
+ goto out;
+ /* Change the size field and recalculate the CRC */
+ ino = c->sbuf + offs;
+ ino->size = cpu_to_le64(e->d_size);
+ len = le32_to_cpu(ino->ch.len);
+ crc = crc32(UBIFS_CRC32_INIT, (void *)ino + 8, len - 8);
+ ino->ch.crc = cpu_to_le32(crc);
+ /* Work out where data in the LEB ends and free space begins */
+ p = c->sbuf;
+ len = c->leb_size - 1;
+ while (p[len] == 0xff)
+ len -= 1;
+ len = ALIGN(len + 1, c->min_io_size);
+ /* Atomically write the fixed LEB back again */
+ err = ubi_leb_change(c->ubi, lnum, c->sbuf, len, UBI_UNKNOWN);
+ if (err)
+ goto out;
+ dbg_rcvry("inode %lu at %d:%d size %lld -> %lld ", e->inum, lnum, offs,
+ i_size, e->d_size);
+ return 0;
+
+out:
+ ubifs_warn("inode %lu failed to fix size %lld -> %lld error %d",
+ e->inum, e->i_size, e->d_size, err);
+ return err;
+}
+
+/**
+ * ubifs_recover_size - recover inode size.
+ * @c: UBIFS file-system description object
+ *
+ * This function attempts to fix inode size discrepancies identified by the
+ * 'ubifs_recover_size_accum()' function.
+ *
+ * This functions returns %0 on success and a negative error code on failure.
+ */
+int ubifs_recover_size(struct ubifs_info *c)
+{
+ struct rb_node *this = rb_first(&c->size_tree);
+
+ while (this) {
+ struct size_entry *e;
+ int err;
+
+ e = rb_entry(this, struct size_entry, rb);
+ if (!e->exists) {
+ union ubifs_key key;
+
+ ino_key_init(c, &key, e->inum);
+ err = ubifs_tnc_lookup(c, &key, c->sbuf);
+ if (err && err != -ENOENT)
+ return err;
+ if (err == -ENOENT) {
+ /* Remove data nodes that have no inode */
+ dbg_rcvry("removing ino %lu", e->inum);
+ err = ubifs_tnc_remove_ino(c, e->inum);
+ if (err)
+ return err;
+ } else {
+ struct ubifs_ino_node *ino = c->sbuf;
+
+ e->exists = 1;
+ e->i_size = le64_to_cpu(ino->size);
+ }
+ }
+ if (e->exists && e->i_size < e->d_size) {
+ if (!e->inode && (c->vfs_sb->s_flags & MS_RDONLY)) {
+ /* Fix the inode size and pin it in memory */
+ struct inode *inode;
+
+ inode = ubifs_iget(c->vfs_sb, e->inum);
+ if (IS_ERR(inode))
+ return PTR_ERR(inode);
+ if (inode->i_size < e->d_size) {
+ dbg_rcvry("ino %lu size %lld -> %lld",
+ e->inum, e->d_size,
+ inode->i_size);
+ inode->i_size = e->d_size;
+ ubifs_inode(inode)->ui_size = e->d_size;
+ e->inode = inode;
+ this = rb_next(this);
+ continue;
+ }
+ iput(inode);
+ } else {
+ /* Fix the size in place */
+ err = fix_size_in_place(c, e);
+ if (err)
+ return err;
+ if (e->inode)
+ iput(e->inode);
+ }
+ }
+ this = rb_next(this);
+ rb_erase(&e->rb, &c->size_tree);
+ kfree(e);
+ }
+ return 0;
+}
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ * Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file contains journal replay code. It runs when the file-system is being
+ * mounted and requires no locking.
+ *
+ * The larger is the journal, the longer it takes to scan it, so the longer it
+ * takes to mount UBIFS. This is why the journal has limited size which may be
+ * changed depending on the system requirements. But a larger journal gives
+ * faster I/O speed because it writes the index less frequently. So this is a
+ * trade-off. Also, the journal is indexed by the in-memory index (TNC), so the
+ * larger is the journal, the more memory its index may consume.
+ */
+
+#include "ubifs.h"
+
+/*
+ * Replay flags.
+ *
+ * REPLAY_DELETION: node was deleted
+ * REPLAY_REF: node is a reference node
+ */
+enum {
+ REPLAY_DELETION = 1,
+ REPLAY_REF = 2,
+};
+
+/**
+ * struct replay_entry - replay tree entry.
+ * @lnum: logical eraseblock number of the node
+ * @offs: node offset
+ * @len: node length
+ * @sqnum: node sequence number
+ * @flags: replay flags
+ * @rb: links the replay tree
+ * @key: node key
+ * @nm: directory entry name
+ * @old_size: truncation old size
+ * @new_size: truncation new size
+ * @free: amount of free space in a bud
+ * @dirty: amount of dirty space in a bud from padding and deletion nodes
+ *
+ * UBIFS journal replay must compare node sequence numbers, which means it must
+ * build a tree of node information to insert into the TNC.
+ */
+struct replay_entry {
+ int lnum;
+ int offs;
+ int len;
+ unsigned long long sqnum;
+ int flags;
+ struct rb_node rb;
+ union ubifs_key key;
+ union {
+ struct qstr nm;
+ struct {
+ loff_t old_size;
+ loff_t new_size;
+ };
+ struct {
+ int free;
+ int dirty;
+ };
+ };
+};
+
+/**
+ * struct bud_entry - entry in the list of buds to replay.
+ * @list: next bud in the list
+ * @bud: bud description object
+ * @free: free bytes in the bud
+ * @sqnum: reference node sequence number
+ */
+struct bud_entry {
+ struct list_head list;
+ struct ubifs_bud *bud;
+ int free;
+ unsigned long long sqnum;
+};
+
+/**
+ * set_bud_lprops - set free and dirty space used by a bud.
+ * @c: UBIFS file-system description object
+ * @r: replay entry of bud
+ */
+static int set_bud_lprops(struct ubifs_info *c, struct replay_entry *r)
+{
+ const struct ubifs_lprops *lp;
+ int err = 0, dirty;
+
+ ubifs_get_lprops(c);
+
+ lp = ubifs_lpt_lookup_dirty(c, r->lnum);
+ if (IS_ERR(lp)) {
+ err = PTR_ERR(lp);
+ goto out;
+ }
+
+ dirty = lp->dirty;
+ if (r->offs == 0 && (lp->free != c->leb_size || lp->dirty != 0)) {
+ /*
+ * The LEB was added to the journal with a starting offset of
+ * zero which means the LEB must have been empty. The LEB
+ * property values should be lp->free == c->leb_size and
+ * lp->dirty == 0, but that is not the case. The reason is that
+ * the LEB was garbage collected. The garbage collector resets
+ * the free and dirty space without recording it anywhere except
+ * lprops, so if there is not a commit then lprops does not have
+ * that information next time the file system is mounted.
+ *
+ * We do not need to adjust free space because the scan has told
+ * us the exact value which is recorded in the replay entry as
+ * r->free.
+ *
+ * However we do need to subtract from the dirty space the
+ * amount of space that the garbage collector reclaimed, which
+ * is the whole LEB minus the amount of space that was free.
+ */
+ dbg_mnt("bud LEB %d was GC'd (%d free, %d dirty)", r->lnum,
+ lp->free, lp->dirty);
+ dbg_gc("bud LEB %d was GC'd (%d free, %d dirty)", r->lnum,
+ lp->free, lp->dirty);
+ dirty -= c->leb_size - lp->free;
+ /*
+ * If the replay order was perfect the dirty space would now be
+ * zero. The order is not perfect because the the journal heads
+ * race with eachother. This is not a problem but is does mean
+ * that the dirty space may temporarily exceed c->leb_size
+ * during the replay.
+ */
+ if (dirty != 0)
+ dbg_msg("LEB %d lp: %d free %d dirty "
+ "replay: %d free %d dirty", r->lnum, lp->free,
+ lp->dirty, r->free, r->dirty);
+ }
+ lp = ubifs_change_lp(c, lp, r->free, dirty + r->dirty,
+ lp->flags | LPROPS_TAKEN, 0);
+ if (IS_ERR(lp)) {
+ err = PTR_ERR(lp);
+ goto out;
+ }
+out:
+ ubifs_release_lprops(c);
+ return err;
+}
+
+/**
+ * trun_remove_range - apply a replay entry for a truncation to the TNC.
+ * @c: UBIFS file-system description object
+ * @r: replay entry of truncation
+ */
+static int trun_remove_range(struct ubifs_info *c, struct replay_entry *r)
+{
+ unsigned min_blk, max_blk;
+ union ubifs_key min_key, max_key;
+ ino_t ino;
+
+ min_blk = r->new_size / UBIFS_BLOCK_SIZE;
+ if (r->new_size & (UBIFS_BLOCK_SIZE - 1))
+ min_blk += 1;
+
+ max_blk = r->old_size / UBIFS_BLOCK_SIZE;
+ if ((r->old_size & (UBIFS_BLOCK_SIZE - 1)) == 0)
+ max_blk -= 1;
+
+ ino = key_inum(c, &r->key);
+
+ data_key_init(c, &min_key, ino, min_blk);
+ data_key_init(c, &max_key, ino, max_blk);
+
+ return ubifs_tnc_remove_range(c, &min_key, &max_key);
+}
+
+/**
+ * apply_replay_entry - apply a replay entry to the TNC.
+ * @c: UBIFS file-system description object
+ * @r: replay entry to apply
+ *
+ * Apply a replay entry to the TNC.
+ */
+static int apply_replay_entry(struct ubifs_info *c, struct replay_entry *r)
+{
+ int err, deletion = ((r->flags & REPLAY_DELETION) != 0);
+
+ dbg_mnt("LEB %d:%d len %d flgs %d sqnum %llu %s", r->lnum,
+ r->offs, r->len, r->flags, r->sqnum, DBGKEY(&r->key));
+
+ /* Set c->replay_sqnum to help deal with dangling branches. */
+ c->replay_sqnum = r->sqnum;
+
+ if (r->flags & REPLAY_REF)
+ err = set_bud_lprops(c, r);
+ else if (is_hash_key(c, &r->key)) {
+ if (deletion)
+ err = ubifs_tnc_remove_nm(c, &r->key, &r->nm);
+ else
+ err = ubifs_tnc_add_nm(c, &r->key, r->lnum, r->offs,
+ r->len, &r->nm);
+ } else {
+ if (deletion)
+ switch (key_type(c, &r->key)) {
+ case UBIFS_INO_KEY:
+ {
+ ino_t inum = key_inum(c, &r->key);
+
+ err = ubifs_tnc_remove_ino(c, inum);
+ break;
+ }
+ case UBIFS_TRUN_KEY:
+ err = trun_remove_range(c, r);
+ break;
+ default:
+ err = ubifs_tnc_remove(c, &r->key);
+ break;
+ }
+ else
+ err = ubifs_tnc_add(c, &r->key, r->lnum, r->offs,
+ r->len);
+ if (err)
+ return err;
+
+ if (c->need_recovery)
+ err = ubifs_recover_size_accum(c, &r->key, deletion,
+ r->new_size);
+ }
+
+ return err;
+}
+
+/**
+ * destroy_replay_tree - destroy the replay.
+ * @c: UBIFS file-system description object
+ *
+ * Destroy the replay tree.
+ */
+static void destroy_replay_tree(struct ubifs_info *c)
+{
+ struct rb_node *this = c->replay_tree.rb_node;
+ struct replay_entry *r;
+
+ while (this) {
+ if (this->rb_left) {
+ this = this->rb_left;
+ continue;
+ } else if (this->rb_right) {
+ this = this->rb_right;
+ continue;
+ }
+ r = rb_entry(this, struct replay_entry, rb);
+ this = rb_parent(this);
+ if (this) {
+ if (this->rb_left == &r->rb)
+ this->rb_left = NULL;
+ else
+ this->rb_right = NULL;
+ }
+ if (is_hash_key(c, &r->key))
+ kfree(r->nm.name);
+ kfree(r);
+ }
+ c->replay_tree = RB_ROOT;
+}
+
+/**
+ * apply_replay_tree - apply the replay tree to the TNC.
+ * @c: UBIFS file-system description object
+ *
+ * Apply the replay tree.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+static int apply_replay_tree(struct ubifs_info *c)
+{
+ struct rb_node *this = rb_first(&c->replay_tree);
+
+ while (this) {
+ struct replay_entry *r;
+ int err;
+
+ cond_resched();
+
+ r = rb_entry(this, struct replay_entry, rb);
+ err = apply_replay_entry(c, r);
+ if (err)
+ return err;
+ this = rb_next(this);
+ }
+ return 0;
+}
+
+/**
+ * insert_node - insert a node to the replay tree.
+ * @c: UBIFS file-system description object
+ * @lnum: node logical eraseblock number
+ * @offs: node offset
+ * @len: node length
+ * @key: node key
+ * @sqnum: sequence number
+ * @deletion: non-zero if this is a deletion
+ * @used: number of bytes in use in a LEB
+ * @old_size: truncation old size
+ * @new_size: truncation new size
+ *
+ * This function inserts a scanned non-direntry node to the replay tree. The
+ * replay tree is an RB-tree containing @struct replay_entry elements which are
+ * indexed by the sequence number. The replay tree is applied at the very end
+ * of the replay process. Since the tree is sorted in sequence number order,
+ * the older modifications are applied first. This function returns zero in
+ * case of success and a negative error code in case of failure.
+ */
+static int insert_node(struct ubifs_info *c, int lnum, int offs, int len,
+ union ubifs_key *key, unsigned long long sqnum,
+ int deletion, int *used, loff_t old_size,
+ loff_t new_size)
+{
+ struct rb_node **p = &c->replay_tree.rb_node, *parent = NULL;
+ struct replay_entry *r;
+
+ if (key_inum(c, key) >= c->highest_inum)
+ c->highest_inum = key_inum(c, key);
+
+ dbg_mnt("add LEB %d:%d, key %s", lnum, offs, DBGKEY(key));
+ while (*p) {
+ parent = *p;
+ r = rb_entry(parent, struct replay_entry, rb);
+ if (sqnum < r->sqnum) {
+ p = &(*p)->rb_left;
+ continue;
+ } else if (sqnum > r->sqnum) {
+ p = &(*p)->rb_right;
+ continue;
+ }
+ ubifs_err("duplicate sqnum in replay");
+ return -EINVAL;
+ }
+
+ r = kzalloc(sizeof(struct replay_entry), GFP_KERNEL);
+ if (!r)
+ return -ENOMEM;
+
+ if (!deletion)
+ *used += ALIGN(len, 8);
+ r->lnum = lnum;
+ r->offs = offs;
+ r->len = len;
+ r->sqnum = sqnum;
+ r->flags = (deletion ? REPLAY_DELETION : 0);
+ r->old_size = old_size;
+ r->new_size = new_size;
+ key_copy(c, key, &r->key);
+
+ rb_link_node(&r->rb, parent, p);
+ rb_insert_color(&r->rb, &c->replay_tree);
+ return 0;
+}
+
+/**
+ * insert_dent - insert a directory entry node into the replay tree.
+ * @c: UBIFS file-system description object
+ * @lnum: node logical eraseblock number
+ * @offs: node offset
+ * @len: node length
+ * @key: node key
+ * @name: directory entry name
+ * @nlen: directory entry name length
+ * @sqnum: sequence number
+ * @deletion: non-zero if this is a deletion
+ * @used: number of bytes in use in a LEB
+ *
+ * This function inserts a scanned directory entry node to the replay tree.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ *
+ * This function is also used for extended attribute entries because they are
+ * implemented as directory entry nodes.
+ */
+static int insert_dent(struct ubifs_info *c, int lnum, int offs, int len,
+ union ubifs_key *key, const char *name, int nlen,
+ unsigned long long sqnum, int deletion, int *used)
+{
+ struct rb_node **p = &c->replay_tree.rb_node, *parent = NULL;
+ struct replay_entry *r;
+ char *nbuf;
+
+ if (key_inum(c, key) >= c->highest_inum)
+ c->highest_inum = key_inum(c, key);
+
+ dbg_mnt("add LEB %d:%d, key %s", lnum, offs, DBGKEY(key));
+ while (*p) {
+ parent = *p;
+ r = rb_entry(parent, struct replay_entry, rb);
+ if (sqnum < r->sqnum) {
+ p = &(*p)->rb_left;
+ continue;
+ }
+ if (sqnum > r->sqnum) {
+ p = &(*p)->rb_right;
+ continue;
+ }
+ ubifs_err("duplicate sqnum in replay");
+ return -EINVAL;
+ }
+
+ r = kzalloc(sizeof(struct replay_entry), GFP_KERNEL);
+ if (!r)
+ return -ENOMEM;
+ nbuf = kmalloc(nlen + 1, GFP_KERNEL);
+ if (!nbuf) {
+ kfree(r);
+ return -ENOMEM;
+ }
+
+ if (!deletion)
+ *used += ALIGN(len, 8);
+ r->lnum = lnum;
+ r->offs = offs;
+ r->len = len;
+ r->sqnum = sqnum;
+ r->nm.len = nlen;
+ memcpy(nbuf, name, nlen);
+ nbuf[nlen] = '\0';
+ r->nm.name = nbuf;
+ r->flags = (deletion ? REPLAY_DELETION : 0);
+ key_copy(c, key, &r->key);
+
+ ubifs_assert(!*p);
+ rb_link_node(&r->rb, parent, p);
+ rb_insert_color(&r->rb, &c->replay_tree);
+ return 0;
+}
+
+/**
+ * ubifs_validate_entry - validate directory or extended attribute entry node.
+ * @c: UBIFS file-system description object
+ * @dent: the node to validate
+ *
+ * This function validates directory or extended attribute entry node @dent.
+ * Returns zero if the node is all right and a %-EINVAL if not.
+ */
+int ubifs_validate_entry(struct ubifs_info *c,
+ const struct ubifs_dent_node *dent)
+{
+ int key_type = key_type_flash(c, dent->key);
+ int nlen = le16_to_cpu(dent->nlen);
+
+ if (le32_to_cpu(dent->ch.len) != nlen + UBIFS_DENT_NODE_SZ + 1 ||
+ dent->type >= UBIFS_ITYPES_CNT ||
+ nlen > UBIFS_MAX_NLEN || dent->name[nlen] != 0 ||
+ strnlen(dent->name, nlen) != nlen ||
+ le64_to_cpu(dent->inum) > MAX_INUM) {
+ ubifs_err("bad %s node", key_type == UBIFS_DENT_KEY ?
+ "directory entry" : "extended attribute entry");
+ return -EINVAL;
+ }
+
+ if (key_type != UBIFS_DENT_KEY && key_type != UBIFS_XENT_KEY) {
+ ubifs_err("bad key type %d", key_type);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/**
+ * replay_bud - replay a bud logical eraseblock.
+ * @c: UBIFS file-system description object
+ * @lnum: bud logical eraseblock number to replay
+ * @offs: bud start offset
+ * @jhead: journal head to which this bud belongs
+ * @free: amount of free space in the bud is returned here
+ * @dirty: amount of dirty space from padding and deletion nodes is returned
+ * here
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int replay_bud(struct ubifs_info *c, int lnum, int offs, int jhead,
+ int *free, int *dirty)
+{
+ int err = 0, used = 0;
+ struct ubifs_scan_leb *sleb;
+ struct ubifs_scan_node *snod;
+ struct ubifs_bud *bud;
+
+ dbg_mnt("replay bud LEB %d, head %d", lnum, jhead);
+ if (c->need_recovery)
+ sleb = ubifs_recover_leb(c, lnum, offs, c->sbuf, jhead != GCHD);
+ else
+ sleb = ubifs_scan(c, lnum, offs, c->sbuf);
+ if (IS_ERR(sleb))
+ return PTR_ERR(sleb);
+
+ /*
+ * The bud does not have to start from offset zero - the beginning of
+ * the 'lnum' LEB may contain previously committed data. One of the
+ * things we have to do in replay is to correctly update lprops with
+ * newer information about this LEB.
+ *
+ * At this point lprops thinks that this LEB has 'c->leb_size - offs'
+ * bytes of free space because it only contain information about
+ * committed data.
+ *
+ * But we know that real amount of free space is 'c->leb_size -
+ * sleb->endpt', and the space in the 'lnum' LEB between 'offs' and
+ * 'sleb->endpt' is used by bud data. We have to correctly calculate
+ * how much of these data are dirty and update lprops with this
+ * information.
+ *
+ * The dirt in that LEB region is comprised of padding nodes, deletion
+ * nodes, truncation nodes and nodes which are obsoleted by subsequent
+ * nodes in this LEB. So instead of calculating clean space, we
+ * calculate used space ('used' variable).
+ */
+
+ list_for_each_entry(snod, &sleb->nodes, list) {
+ int deletion = 0;
+
+ cond_resched();
+
+ if (snod->sqnum >= SQNUM_WATERMARK) {
+ ubifs_err("file system's life ended");
+ goto out_dump;
+ }
+
+ if (snod->sqnum > c->max_sqnum)
+ c->max_sqnum = snod->sqnum;
+
+ switch (snod->type) {
+ case UBIFS_INO_NODE:
+ {
+ struct ubifs_ino_node *ino = snod->node;
+ loff_t new_size = le64_to_cpu(ino->size);
+
+ if (le32_to_cpu(ino->nlink) == 0)
+ deletion = 1;
+ err = insert_node(c, lnum, snod->offs, snod->len,
+ &snod->key, snod->sqnum, deletion,
+ &used, 0, new_size);
+ break;
+ }
+ case UBIFS_DATA_NODE:
+ {
+ struct ubifs_data_node *dn = snod->node;
+ loff_t new_size = le32_to_cpu(dn->size) +
+ key_block(c, &snod->key) *
+ UBIFS_BLOCK_SIZE;
+
+ err = insert_node(c, lnum, snod->offs, snod->len,
+ &snod->key, snod->sqnum, deletion,
+ &used, 0, new_size);
+ break;
+ }
+ case UBIFS_DENT_NODE:
+ case UBIFS_XENT_NODE:
+ {
+ struct ubifs_dent_node *dent = snod->node;
+
+ err = ubifs_validate_entry(c, dent);
+ if (err)
+ goto out_dump;
+
+ err = insert_dent(c, lnum, snod->offs, snod->len,
+ &snod->key, dent->name,
+ le16_to_cpu(dent->nlen), snod->sqnum,
+ !le64_to_cpu(dent->inum), &used);
+ break;
+ }
+ case UBIFS_TRUN_NODE:
+ {
+ struct ubifs_trun_node *trun = snod->node;
+ loff_t old_size = le64_to_cpu(trun->old_size);
+ loff_t new_size = le64_to_cpu(trun->new_size);
+ union ubifs_key key;
+
+ /* Validate truncation node */
+ if (old_size < 0 || old_size > c->max_inode_sz ||
+ new_size < 0 || new_size > c->max_inode_sz ||
+ old_size <= new_size) {
+ ubifs_err("bad truncation node");
+ goto out_dump;
+ }
+
+ /*
+ * Create a fake truncation key just to use the same
+ * functions which expect nodes to have keys.
+ */
+ trun_key_init(c, &key, le32_to_cpu(trun->inum));
+ err = insert_node(c, lnum, snod->offs, snod->len,
+ &key, snod->sqnum, 1, &used,
+ old_size, new_size);
+ break;
+ }
+ default:
+ ubifs_err("unexpected node type %d in bud LEB %d:%d",
+ snod->type, lnum, snod->offs);
+ err = -EINVAL;
+ goto out_dump;
+ }
+ if (err)
+ goto out;
+ }
+
+ bud = ubifs_search_bud(c, lnum);
+ if (!bud)
+ BUG();
+
+ ubifs_assert(sleb->endpt - offs >= used);
+ ubifs_assert(sleb->endpt % c->min_io_size == 0);
+
+ if (sleb->endpt + c->min_io_size <= c->leb_size &&
+ !(c->vfs_sb->s_flags & MS_RDONLY))
+ err = ubifs_wbuf_seek_nolock(&c->jheads[jhead].wbuf, lnum,
+ sleb->endpt, UBI_SHORTTERM);
+
+ *dirty = sleb->endpt - offs - used;
+ *free = c->leb_size - sleb->endpt;
+
+out:
+ ubifs_scan_destroy(sleb);
+ return err;
+
+out_dump:
+ ubifs_err("bad node is at LEB %d:%d", lnum, snod->offs);
+ dbg_dump_node(c, snod->node);
+ ubifs_scan_destroy(sleb);
+ return -EINVAL;
+}
+
+/**
+ * insert_ref_node - insert a reference node to the replay tree.
+ * @c: UBIFS file-system description object
+ * @lnum: node logical eraseblock number
+ * @offs: node offset
+ * @sqnum: sequence number
+ * @free: amount of free space in bud
+ * @dirty: amount of dirty space from padding and deletion nodes
+ *
+ * This function inserts a reference node to the replay tree and returns zero
+ * in case of success ort a negative error code in case of failure.
+ */
+static int insert_ref_node(struct ubifs_info *c, int lnum, int offs,
+ unsigned long long sqnum, int free, int dirty)
+{
+ struct rb_node **p = &c->replay_tree.rb_node, *parent = NULL;
+ struct replay_entry *r;
+
+ dbg_mnt("add ref LEB %d:%d", lnum, offs);
+ while (*p) {
+ parent = *p;
+ r = rb_entry(parent, struct replay_entry, rb);
+ if (sqnum < r->sqnum) {
+ p = &(*p)->rb_left;
+ continue;
+ } else if (sqnum > r->sqnum) {
+ p = &(*p)->rb_right;
+ continue;
+ }
+ ubifs_err("duplicate sqnum in replay tree");
+ return -EINVAL;
+ }
+
+ r = kzalloc(sizeof(struct replay_entry), GFP_KERNEL);
+ if (!r)
+ return -ENOMEM;
+
+ r->lnum = lnum;
+ r->offs = offs;
+ r->sqnum = sqnum;
+ r->flags = REPLAY_REF;
+ r->free = free;
+ r->dirty = dirty;
+
+ rb_link_node(&r->rb, parent, p);
+ rb_insert_color(&r->rb, &c->replay_tree);
+ return 0;
+}
+
+/**
+ * replay_buds - replay all buds.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int replay_buds(struct ubifs_info *c)
+{
+ struct bud_entry *b;
+ int err, uninitialized_var(free), uninitialized_var(dirty);
+
+ list_for_each_entry(b, &c->replay_buds, list) {
+ err = replay_bud(c, b->bud->lnum, b->bud->start, b->bud->jhead,
+ &free, &dirty);
+ if (err)
+ return err;
+ err = insert_ref_node(c, b->bud->lnum, b->bud->start, b->sqnum,
+ free, dirty);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
+/**
+ * destroy_bud_list - destroy the list of buds to replay.
+ * @c: UBIFS file-system description object
+ */
+static void destroy_bud_list(struct ubifs_info *c)
+{
+ struct bud_entry *b;
+
+ while (!list_empty(&c->replay_buds)) {
+ b = list_entry(c->replay_buds.next, struct bud_entry, list);
+ list_del(&b->list);
+ kfree(b);
+ }
+}
+
+/**
+ * add_replay_bud - add a bud to the list of buds to replay.
+ * @c: UBIFS file-system description object
+ * @lnum: bud logical eraseblock number to replay
+ * @offs: bud start offset
+ * @jhead: journal head to which this bud belongs
+ * @sqnum: reference node sequence number
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int add_replay_bud(struct ubifs_info *c, int lnum, int offs, int jhead,
+ unsigned long long sqnum)
+{
+ struct ubifs_bud *bud;
+ struct bud_entry *b;
+
+ dbg_mnt("add replay bud LEB %d:%d, head %d", lnum, offs, jhead);
+
+ bud = kmalloc(sizeof(struct ubifs_bud), GFP_KERNEL);
+ if (!bud)
+ return -ENOMEM;
+
+ b = kmalloc(sizeof(struct bud_entry), GFP_KERNEL);
+ if (!b) {
+ kfree(bud);
+ return -ENOMEM;
+ }
+
+ bud->lnum = lnum;
+ bud->start = offs;
+ bud->jhead = jhead;
+ ubifs_add_bud(c, bud);
+
+ b->bud = bud;
+ b->sqnum = sqnum;
+ list_add_tail(&b->list, &c->replay_buds);
+
+ return 0;
+}
+
+/**
+ * validate_ref - validate a reference node.
+ * @c: UBIFS file-system description object
+ * @ref: the reference node to validate
+ * @ref_lnum: LEB number of the reference node
+ * @ref_offs: reference node offset
+ *
+ * This function returns %1 if a bud reference already exists for the LEB. %0 is
+ * returned if the reference node is new, otherwise %-EINVAL is returned if
+ * validation failed.
+ */
+static int validate_ref(struct ubifs_info *c, const struct ubifs_ref_node *ref)
+{
+ struct ubifs_bud *bud;
+ int lnum = le32_to_cpu(ref->lnum);
+ unsigned int offs = le32_to_cpu(ref->offs);
+ unsigned int jhead = le32_to_cpu(ref->jhead);
+
+ /*
+ * ref->offs may point to the end of LEB when the journal head points
+ * to the end of LEB and we write reference node for it during commit.
+ * So this is why we require 'offs > c->leb_size'.
+ */
+ if (jhead >= c->jhead_cnt || lnum >= c->leb_cnt ||
+ lnum < c->main_first || offs > c->leb_size ||
+ offs & (c->min_io_size - 1))
+ return -EINVAL;
+
+ /* Make sure we have not already looked at this bud */
+ bud = ubifs_search_bud(c, lnum);
+ if (bud) {
+ if (bud->jhead == jhead && bud->start <= offs)
+ return 1;
+ ubifs_err("bud at LEB %d:%d was already referred", lnum, offs);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/**
+ * replay_log_leb - replay a log logical eraseblock.
+ * @c: UBIFS file-system description object
+ * @lnum: log logical eraseblock to replay
+ * @offs: offset to start replaying from
+ * @sbuf: scan buffer
+ *
+ * This function replays a log LEB and returns zero in case of success, %1 if
+ * this is the last LEB in the log, and a negative error code in case of
+ * failure.
+ */
+static int replay_log_leb(struct ubifs_info *c, int lnum, int offs, void *sbuf)
+{
+ int err;
+ struct ubifs_scan_leb *sleb;
+ struct ubifs_scan_node *snod;
+ const struct ubifs_cs_node *node;
+
+ dbg_mnt("replay log LEB %d:%d", lnum, offs);
+ sleb = ubifs_scan(c, lnum, offs, sbuf);
+ if (IS_ERR(sleb)) {
+ if (c->need_recovery)
+ sleb = ubifs_recover_log_leb(c, lnum, offs, sbuf);
+ if (IS_ERR(sleb))
+ return PTR_ERR(sleb);
+ }
+
+ if (sleb->nodes_cnt == 0) {
+ err = 1;
+ goto out;
+ }
+
+ node = sleb->buf;
+
+ snod = list_entry(sleb->nodes.next, struct ubifs_scan_node, list);
+ if (c->cs_sqnum == 0) {
+ /*
+ * This is the first log LEB we are looking at, make sure that
+ * the first node is a commit start node. Also record its
+ * sequence number so that UBIFS can determine where the log
+ * ends, because all nodes which were have higher sequence
+ * numbers.
+ */
+ if (snod->type != UBIFS_CS_NODE) {
+ dbg_err("first log node at LEB %d:%d is not CS node",
+ lnum, offs);
+ goto out_dump;
+ }
+ if (le64_to_cpu(node->cmt_no) != c->cmt_no) {
+ dbg_err("first CS node at LEB %d:%d has wrong "
+ "commit number %llu expected %llu",
+ lnum, offs,
+ (unsigned long long)le64_to_cpu(node->cmt_no),
+ c->cmt_no);
+ goto out_dump;
+ }
+
+ c->cs_sqnum = le64_to_cpu(node->ch.sqnum);
+ dbg_mnt("commit start sqnum %llu", c->cs_sqnum);
+ }
+
+ if (snod->sqnum < c->cs_sqnum) {
+ /*
+ * This means that we reached end of log and now
+ * look to the older log data, which was already
+ * committed but the eraseblock was not erased (UBIFS
+ * only unmaps it). So this basically means we have to
+ * exit with "end of log" code.
+ */
+ err = 1;
+ goto out;
+ }
+
+ /* Make sure the first node sits at offset zero of the LEB */
+ if (snod->offs != 0) {
+ dbg_err("first node is not at zero offset");
+ goto out_dump;
+ }
+
+ list_for_each_entry(snod, &sleb->nodes, list) {
+
+ cond_resched();
+
+ if (snod->sqnum >= SQNUM_WATERMARK) {
+ ubifs_err("file system's life ended");
+ goto out_dump;
+ }
+
+ if (snod->sqnum < c->cs_sqnum) {
+ dbg_err("bad sqnum %llu, commit sqnum %llu",
+ snod->sqnum, c->cs_sqnum);
+ goto out_dump;
+ }
+
+ if (snod->sqnum > c->max_sqnum)
+ c->max_sqnum = snod->sqnum;
+
+ switch (snod->type) {
+ case UBIFS_REF_NODE: {
+ const struct ubifs_ref_node *ref = snod->node;
+
+ err = validate_ref(c, ref);
+ if (err == 1)
+ break; /* Already have this bud */
+ if (err)
+ goto out_dump;
+
+ err = add_replay_bud(c, le32_to_cpu(ref->lnum),
+ le32_to_cpu(ref->offs),
+ le32_to_cpu(ref->jhead),
+ snod->sqnum);
+ if (err)
+ goto out;
+
+ break;
+ }
+ case UBIFS_CS_NODE:
+ /* Make sure it sits at the beginning of LEB */
+ if (snod->offs != 0) {
+ ubifs_err("unexpected node in log");
+ goto out_dump;
+ }
+ break;
+ default:
+ ubifs_err("unexpected node in log");
+ goto out_dump;
+ }
+ }
+
+ if (sleb->endpt || c->lhead_offs >= c->leb_size) {
+ c->lhead_lnum = lnum;
+ c->lhead_offs = sleb->endpt;
+ }
+
+ err = !sleb->endpt;
+out:
+ ubifs_scan_destroy(sleb);
+ return err;
+
+out_dump:
+ ubifs_err("log error detected while replying the log at LEB %d:%d",
+ lnum, offs + snod->offs);
+ dbg_dump_node(c, snod->node);
+ ubifs_scan_destroy(sleb);
+ return -EINVAL;
+}
+
+/**
+ * take_ihead - update the status of the index head in lprops to 'taken'.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns the amount of free space in the index head LEB or a
+ * negative error code.
+ */
+static int take_ihead(struct ubifs_info *c)
+{
+ const struct ubifs_lprops *lp;
+ int err, free;
+
+ ubifs_get_lprops(c);
+
+ lp = ubifs_lpt_lookup_dirty(c, c->ihead_lnum);
+ if (IS_ERR(lp)) {
+ err = PTR_ERR(lp);
+ goto out;
+ }
+
+ free = lp->free;
+
+ lp = ubifs_change_lp(c, lp, LPROPS_NC, LPROPS_NC,
+ lp->flags | LPROPS_TAKEN, 0);
+ if (IS_ERR(lp)) {
+ err = PTR_ERR(lp);
+ goto out;
+ }
+
+ err = free;
+out:
+ ubifs_release_lprops(c);
+ return err;
+}
+
+/**
+ * ubifs_replay_journal - replay journal.
+ * @c: UBIFS file-system description object
+ *
+ * This function scans the journal, replays and cleans it up. It makes sure all
+ * memory data structures related to uncommitted journal are built (dirty TNC
+ * tree, tree of buds, modified lprops, etc).
+ */
+int ubifs_replay_journal(struct ubifs_info *c)
+{
+ int err, i, lnum, offs, free;
+ void *sbuf = NULL;
+
+ BUILD_BUG_ON(UBIFS_TRUN_KEY > 5);
+
+ /* Update the status of the index head in lprops to 'taken' */
+ free = take_ihead(c);
+ if (free < 0)
+ return free; /* Error code */
+
+ if (c->ihead_offs != c->leb_size - free) {
+ ubifs_err("bad index head LEB %d:%d", c->ihead_lnum,
+ c->ihead_offs);
+ return -EINVAL;
+ }
+
+ sbuf = vmalloc(c->leb_size);
+ if (!sbuf)
+ return -ENOMEM;
+
+ dbg_mnt("start replaying the journal");
+
+ c->replaying = 1;
+
+ lnum = c->ltail_lnum = c->lhead_lnum;
+ offs = c->lhead_offs;
+
+ for (i = 0; i < c->log_lebs; i++, lnum++) {
+ if (lnum >= UBIFS_LOG_LNUM + c->log_lebs) {
+ /*
+ * The log is logically circular, we reached the last
+ * LEB, switch to the first one.
+ */
+ lnum = UBIFS_LOG_LNUM;
+ offs = 0;
+ }
+ err = replay_log_leb(c, lnum, offs, sbuf);
+ if (err == 1)
+ /* We hit the end of the log */
+ break;
+ if (err)
+ goto out;
+ offs = 0;
+ }
+
+ err = replay_buds(c);
+ if (err)
+ goto out;
+
+ err = apply_replay_tree(c);
+ if (err)
+ goto out;
+
+ ubifs_assert(c->bud_bytes <= c->max_bud_bytes || c->need_recovery);
+ dbg_mnt("finished, log head LEB %d:%d, max_sqnum %llu, "
+ "highest_inum %lu", c->lhead_lnum, c->lhead_offs, c->max_sqnum,
+ c->highest_inum);
+out:
+ destroy_replay_tree(c);
+ destroy_bud_list(c);
+ vfree(sbuf);
+ c->replaying = 0;
+ return err;
+}
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ * Adrian Hunter
+ */
+
+/*
+ * This file implements UBIFS superblock. The superblock is stored at the first
+ * LEB of the volume and is never changed by UBIFS. Only user-space tools may
+ * change it. The superblock node mostly contains geometry information.
+ */
+
+#include "ubifs.h"
+#include <linux/random.h>
+
+/*
+ * Default journal size in logical eraseblocks as a percent of total
+ * flash size.
+ */
+#define DEFAULT_JNL_PERCENT 5
+
+/* Default maximum journal size in bytes */
+#define DEFAULT_MAX_JNL (32*1024*1024)
+
+/* Default indexing tree fanout */
+#define DEFAULT_FANOUT 8
+
+/* Default number of data journal heads */
+#define DEFAULT_JHEADS_CNT 1
+
+/* Default positions of different LEBs in the main area */
+#define DEFAULT_IDX_LEB 0
+#define DEFAULT_DATA_LEB 1
+#define DEFAULT_GC_LEB 2
+
+/* Default number of LEB numbers in LPT's save table */
+#define DEFAULT_LSAVE_CNT 256
+
+/* Default reserved pool size as a percent of maximum free space */
+#define DEFAULT_RP_PERCENT 5
+
+/* The default maximum size of reserved pool in bytes */
+#define DEFAULT_MAX_RP_SIZE (5*1024*1024)
+
+/* Default time granularity in nanoseconds */
+#define DEFAULT_TIME_GRAN 1000000000
+
+/**
+ * create_default_filesystem - format empty UBI volume.
+ * @c: UBIFS file-system description object
+ *
+ * This function creates default empty file-system. Returns zero in case of
+ * success and a negative error code in case of failure.
+ */
+static int create_default_filesystem(struct ubifs_info *c)
+{
+ struct ubifs_sb_node *sup;
+ struct ubifs_mst_node *mst;
+ struct ubifs_idx_node *idx;
+ struct ubifs_branch *br;
+ struct ubifs_ino_node *ino;
+ struct ubifs_cs_node *cs;
+ union ubifs_key key;
+ int err, tmp, jnl_lebs, log_lebs, max_buds, main_lebs, main_first;
+ int lpt_lebs, lpt_first, orph_lebs, big_lpt, ino_waste, sup_flags = 0;
+ int min_leb_cnt = UBIFS_MIN_LEB_CNT;
+ uint64_t tmp64, main_bytes;
+
+ /* Some functions called from here depend on the @c->key_len filed */
+ c->key_len = UBIFS_SK_LEN;
+
+ /*
+ * First of all, we have to calculate default file-system geometry -
+ * log size, journal size, etc.
+ */
+ if (c->leb_cnt < 0x7FFFFFFF / DEFAULT_JNL_PERCENT)
+ /* We can first multiply then divide and have no overflow */
+ jnl_lebs = c->leb_cnt * DEFAULT_JNL_PERCENT / 100;
+ else
+ jnl_lebs = (c->leb_cnt / 100) * DEFAULT_JNL_PERCENT;
+
+ if (jnl_lebs < UBIFS_MIN_JNL_LEBS)
+ jnl_lebs = UBIFS_MIN_JNL_LEBS;
+ if (jnl_lebs * c->leb_size > DEFAULT_MAX_JNL)
+ jnl_lebs = DEFAULT_MAX_JNL / c->leb_size;
+
+ /*
+ * The log should be large enough to fit reference nodes for all bud
+ * LEBs. Because buds do not have to start from the beginning of LEBs
+ * (half of the LEB may contain committed data), the log should
+ * generally be larger, make it twice as large.
+ */
+ tmp = 2 * (c->ref_node_alsz * jnl_lebs) + c->leb_size - 1;
+ log_lebs = tmp / c->leb_size;
+ /* Plus one LEB reserved for commit */
+ log_lebs += 1;
+ if (c->leb_cnt - min_leb_cnt > 8) {
+ /* And some extra space to allow writes while committing */
+ log_lebs += 1;
+ min_leb_cnt += 1;
+ }
+
+ max_buds = jnl_lebs - log_lebs;
+ if (max_buds < UBIFS_MIN_BUD_LEBS)
+ max_buds = UBIFS_MIN_BUD_LEBS;
+
+ /*
+ * Orphan nodes are stored in a separate area. One node can store a lot
+ * of orphan inode numbers, but when new orphan comes we just add a new
+ * orphan node. At some point the nodes are consolidated into one
+ * orphan node.
+ */
+ orph_lebs = UBIFS_MIN_ORPH_LEBS;
+#ifdef CONFIG_UBIFS_FS_DEBUG
+ if (c->leb_cnt - min_leb_cnt > 1)
+ /*
+ * For debugging purposes it is better to have at least 2
+ * orphan LEBs, because the orphan subsystem would need to do
+ * consolidations and would be stressed more.
+ */
+ orph_lebs += 1;
+#endif
+
+ main_lebs = c->leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS - log_lebs;
+ main_lebs -= orph_lebs;
+
+ lpt_first = UBIFS_LOG_LNUM + log_lebs;
+ c->lsave_cnt = DEFAULT_LSAVE_CNT;
+ c->max_leb_cnt = c->leb_cnt;
+ err = ubifs_create_dflt_lpt(c, &main_lebs, lpt_first, &lpt_lebs,
+ &big_lpt);
+ if (err)
+ return err;
+
+ dbg_gen("LEB Properties Tree created (LEBs %d-%d)", lpt_first,
+ lpt_first + lpt_lebs - 1);
+
+ main_first = c->leb_cnt - main_lebs;
+
+ /* Create default superblock */
+ tmp = ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size);
+ sup = kzalloc(tmp, GFP_KERNEL);
+ if (!sup)
+ return -ENOMEM;
+
+ tmp64 = (uint64_t)max_buds * c->leb_size;
+ if (big_lpt)
+ sup_flags |= UBIFS_FLG_BIGLPT;
+
+ sup->ch.node_type = UBIFS_SB_NODE;
+ sup->key_hash = UBIFS_KEY_HASH_R5;
+ sup->flags = cpu_to_le32(sup_flags);
+ sup->min_io_size = cpu_to_le32(c->min_io_size);
+ sup->leb_size = cpu_to_le32(c->leb_size);
+ sup->leb_cnt = cpu_to_le32(c->leb_cnt);
+ sup->max_leb_cnt = cpu_to_le32(c->max_leb_cnt);
+ sup->max_bud_bytes = cpu_to_le64(tmp64);
+ sup->log_lebs = cpu_to_le32(log_lebs);
+ sup->lpt_lebs = cpu_to_le32(lpt_lebs);
+ sup->orph_lebs = cpu_to_le32(orph_lebs);
+ sup->jhead_cnt = cpu_to_le32(DEFAULT_JHEADS_CNT);
+ sup->fanout = cpu_to_le32(DEFAULT_FANOUT);
+ sup->lsave_cnt = cpu_to_le32(c->lsave_cnt);
+ sup->fmt_version = cpu_to_le32(UBIFS_FORMAT_VERSION);
+ sup->default_compr = cpu_to_le16(UBIFS_COMPR_LZO);
+ sup->time_gran = cpu_to_le32(DEFAULT_TIME_GRAN);
+
+ generate_random_uuid(sup->uuid);
+
+ main_bytes = (uint64_t)main_lebs * c->leb_size;
+ tmp64 = main_bytes * DEFAULT_RP_PERCENT;
+ do_div(tmp64, 100);
+ if (tmp64 > DEFAULT_MAX_RP_SIZE)
+ tmp64 = DEFAULT_MAX_RP_SIZE;
+ sup->rp_size = cpu_to_le64(tmp64);
+
+ err = ubifs_write_node(c, sup, UBIFS_SB_NODE_SZ, 0, 0, UBI_LONGTERM);
+ kfree(sup);
+ if (err)
+ return err;
+
+ dbg_gen("default superblock created at LEB 0:0");
+
+ /* Create default master node */
+ mst = kzalloc(c->mst_node_alsz, GFP_KERNEL);
+ if (!mst)
+ return -ENOMEM;
+
+ mst->ch.node_type = UBIFS_MST_NODE;
+ mst->log_lnum = cpu_to_le32(UBIFS_LOG_LNUM);
+ mst->highest_inum = cpu_to_le64(UBIFS_FIRST_INO);
+ mst->cmt_no = 0;
+ mst->root_lnum = cpu_to_le32(main_first + DEFAULT_IDX_LEB);
+ mst->root_offs = 0;
+ tmp = ubifs_idx_node_sz(c, 1);
+ mst->root_len = cpu_to_le32(tmp);
+ mst->gc_lnum = cpu_to_le32(main_first + DEFAULT_GC_LEB);
+ mst->ihead_lnum = cpu_to_le32(main_first + DEFAULT_IDX_LEB);
+ mst->ihead_offs = cpu_to_le32(ALIGN(tmp, c->min_io_size));
+ mst->index_size = cpu_to_le64(ALIGN(tmp, 8));
+ mst->lpt_lnum = cpu_to_le32(c->lpt_lnum);
+ mst->lpt_offs = cpu_to_le32(c->lpt_offs);
+ mst->nhead_lnum = cpu_to_le32(c->nhead_lnum);
+ mst->nhead_offs = cpu_to_le32(c->nhead_offs);
+ mst->ltab_lnum = cpu_to_le32(c->ltab_lnum);
+ mst->ltab_offs = cpu_to_le32(c->ltab_offs);
+ mst->lsave_lnum = cpu_to_le32(c->lsave_lnum);
+ mst->lsave_offs = cpu_to_le32(c->lsave_offs);
+ mst->lscan_lnum = cpu_to_le32(main_first);
+ mst->empty_lebs = cpu_to_le32(main_lebs - 2);
+ mst->idx_lebs = cpu_to_le32(1);
+ mst->leb_cnt = cpu_to_le32(c->leb_cnt);
+
+ /* Calculate lprops statistics */
+ tmp64 = main_bytes;
+ tmp64 -= ALIGN(ubifs_idx_node_sz(c, 1), c->min_io_size);
+ tmp64 -= ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size);
+ mst->total_free = cpu_to_le64(tmp64);
+
+ tmp64 = ALIGN(ubifs_idx_node_sz(c, 1), c->min_io_size);
+ ino_waste = ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size) -
+ UBIFS_INO_NODE_SZ;
+ tmp64 += ino_waste;
+ tmp64 -= ALIGN(ubifs_idx_node_sz(c, 1), 8);
+ mst->total_dirty = cpu_to_le64(tmp64);
+
+ /* The indexing LEB does not contribute to dark space */
+ tmp64 = (c->main_lebs - 1) * c->dark_wm;
+ mst->total_dark = cpu_to_le64(tmp64);
+
+ mst->total_used = cpu_to_le64(UBIFS_INO_NODE_SZ);
+
+ err = ubifs_write_node(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM, 0,
+ UBI_UNKNOWN);
+ if (err) {
+ kfree(mst);
+ return err;
+ }
+ err = ubifs_write_node(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM + 1, 0,
+ UBI_UNKNOWN);
+ kfree(mst);
+ if (err)
+ return err;
+
+ dbg_gen("default master node created at LEB %d:0", UBIFS_MST_LNUM);
+
+ /* Create the root indexing node */
+ tmp = ubifs_idx_node_sz(c, 1);
+ idx = kzalloc(ALIGN(tmp, c->min_io_size), GFP_KERNEL);
+ if (!idx)
+ return -ENOMEM;
+
+ c->key_fmt = UBIFS_SIMPLE_KEY_FMT;
+ c->key_hash = key_r5_hash;
+
+ idx->ch.node_type = UBIFS_IDX_NODE;
+ idx->child_cnt = cpu_to_le16(1);
+ ino_key_init(c, &key, UBIFS_ROOT_INO);
+ br = ubifs_idx_branch(c, idx, 0);
+ key_write_idx(c, &key, &br->key);
+ br->lnum = cpu_to_le32(main_first + DEFAULT_DATA_LEB);
+ br->len = cpu_to_le32(UBIFS_INO_NODE_SZ);
+ err = ubifs_write_node(c, idx, tmp, main_first + DEFAULT_IDX_LEB, 0,
+ UBI_UNKNOWN);
+ kfree(idx);
+ if (err)
+ return err;
+
+ dbg_gen("default root indexing node created LEB %d:0",
+ main_first + DEFAULT_IDX_LEB);
+
+ /* Create default root inode */
+ tmp = ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size);
+ ino = kzalloc(tmp, GFP_KERNEL);
+ if (!ino)
+ return -ENOMEM;
+
+ ino_key_init_flash(c, &ino->key, UBIFS_ROOT_INO);
+ ino->ch.node_type = UBIFS_INO_NODE;
+ ino->creat_sqnum = cpu_to_le64(++c->max_sqnum);
+ ino->nlink = cpu_to_le32(2);
+ tmp = cpu_to_le64(CURRENT_TIME_SEC.tv_sec);
+ ino->atime_sec = tmp;
+ ino->ctime_sec = tmp;
+ ino->mtime_sec = tmp;
+ ino->atime_nsec = 0;
+ ino->ctime_nsec = 0;
+ ino->mtime_nsec = 0;
+ ino->mode = cpu_to_le32(S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO);
+ ino->size = cpu_to_le64(UBIFS_INO_NODE_SZ);
+
+ /* Set compression enabled by default */
+ ino->flags = cpu_to_le32(UBIFS_COMPR_FL);
+
+ err = ubifs_write_node(c, ino, UBIFS_INO_NODE_SZ,
+ main_first + DEFAULT_DATA_LEB, 0,
+ UBI_UNKNOWN);
+ kfree(ino);
+ if (err)
+ return err;
+
+ dbg_gen("root inode created at LEB %d:0",
+ main_first + DEFAULT_DATA_LEB);
+
+ /*
+ * The first node in the log has to be the commit start node. This is
+ * always the case during normal file-system operation. Write a fake
+ * commit start node to the log.
+ */
+ tmp = ALIGN(UBIFS_CS_NODE_SZ, c->min_io_size);
+ cs = kzalloc(tmp, GFP_KERNEL);
+ if (!cs)
+ return -ENOMEM;
+
+ cs->ch.node_type = UBIFS_CS_NODE;
+ err = ubifs_write_node(c, cs, UBIFS_CS_NODE_SZ, UBIFS_LOG_LNUM,
+ 0, UBI_UNKNOWN);
+ kfree(cs);
+
+ ubifs_msg("default file-system created");
+ return 0;
+}
+
+/**
+ * validate_sb - validate superblock node.
+ * @c: UBIFS file-system description object
+ * @sup: superblock node
+ *
+ * This function validates superblock node @sup. Since most of data was read
+ * from the superblock and stored in @c, the function validates fields in @c
+ * instead. Returns zero in case of success and %-EINVAL in case of validation
+ * failure.
+ */
+static int validate_sb(struct ubifs_info *c, struct ubifs_sb_node *sup)
+{
+ long long max_bytes;
+ int err = 1, min_leb_cnt;
+
+ if (!c->key_hash) {
+ err = 2;
+ goto failed;
+ }
+
+ if (sup->key_fmt != UBIFS_SIMPLE_KEY_FMT) {
+ err = 3;
+ goto failed;
+ }
+
+ if (le32_to_cpu(sup->min_io_size) != c->min_io_size) {
+ ubifs_err("min. I/O unit mismatch: %d in superblock, %d real",
+ le32_to_cpu(sup->min_io_size), c->min_io_size);
+ goto failed;
+ }
+
+ if (le32_to_cpu(sup->leb_size) != c->leb_size) {
+ ubifs_err("LEB size mismatch: %d in superblock, %d real",
+ le32_to_cpu(sup->leb_size), c->leb_size);
+ goto failed;
+ }
+
+ if (c->log_lebs < UBIFS_MIN_LOG_LEBS ||
+ c->lpt_lebs < UBIFS_MIN_LPT_LEBS ||
+ c->orph_lebs < UBIFS_MIN_ORPH_LEBS ||
+ c->main_lebs < UBIFS_MIN_MAIN_LEBS) {
+ err = 4;
+ goto failed;
+ }
+
+ /*
+ * Calculate minimum allowed amount of main area LEBs. This is very
+ * similar to %UBIFS_MIN_LEB_CNT, but we take into account real what we
+ * have just read from the superblock.
+ */
+ min_leb_cnt = UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs;
+ min_leb_cnt += c->lpt_lebs + c->orph_lebs + c->jhead_cnt + 6;
+
+ if (c->leb_cnt < min_leb_cnt || c->leb_cnt > c->vi.size) {
+ ubifs_err("bad LEB count: %d in superblock, %d on UBI volume, "
+ "%d minimum required", c->leb_cnt, c->vi.size,
+ min_leb_cnt);
+ goto failed;
+ }
+
+ if (c->max_leb_cnt < c->leb_cnt) {
+ ubifs_err("max. LEB count %d less than LEB count %d",
+ c->max_leb_cnt, c->leb_cnt);
+ goto failed;
+ }
+
+ if (c->main_lebs < UBIFS_MIN_MAIN_LEBS) {
+ err = 7;
+ goto failed;
+ }
+
+ if (c->max_bud_bytes < (long long)c->leb_size * UBIFS_MIN_BUD_LEBS ||
+ c->max_bud_bytes > (long long)c->leb_size * c->main_lebs) {
+ err = 8;
+ goto failed;
+ }
+
+ if (c->jhead_cnt < NONDATA_JHEADS_CNT + 1 ||
+ c->jhead_cnt > NONDATA_JHEADS_CNT + UBIFS_MAX_JHEADS) {
+ err = 9;
+ goto failed;
+ }
+
+ if (c->fanout < UBIFS_MIN_FANOUT ||
+ ubifs_idx_node_sz(c, c->fanout) > c->leb_size) {
+ err = 10;
+ goto failed;
+ }
+
+ if (c->lsave_cnt < 0 || (c->lsave_cnt > DEFAULT_LSAVE_CNT &&
+ c->lsave_cnt > c->max_leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS -
+ c->log_lebs - c->lpt_lebs - c->orph_lebs)) {
+ err = 11;
+ goto failed;
+ }
+
+ if (UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs + c->lpt_lebs +
+ c->orph_lebs + c->main_lebs != c->leb_cnt) {
+ err = 12;
+ goto failed;
+ }
+
+ if (c->default_compr < 0 || c->default_compr >= UBIFS_COMPR_TYPES_CNT) {
+ err = 13;
+ goto failed;
+ }
+
+ max_bytes = c->main_lebs * (long long)c->leb_size;
+ if (c->rp_size < 0 || max_bytes < c->rp_size) {
+ err = 14;
+ goto failed;
+ }
+
+ if (le32_to_cpu(sup->time_gran) > 1000000000 ||
+ le32_to_cpu(sup->time_gran) < 1) {
+ err = 15;
+ goto failed;
+ }
+
+ return 0;
+
+failed:
+ ubifs_err("bad superblock, error %d", err);
+ dbg_dump_node(c, sup);
+ return -EINVAL;
+}
+
+/**
+ * ubifs_read_sb_node - read superblock node.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns a pointer to the superblock node or a negative error
+ * code.
+ */
+struct ubifs_sb_node *ubifs_read_sb_node(struct ubifs_info *c)
+{
+ struct ubifs_sb_node *sup;
+ int err;
+
+ sup = kmalloc(ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size), GFP_NOFS);
+ if (!sup)
+ return ERR_PTR(-ENOMEM);
+
+ err = ubifs_read_node(c, sup, UBIFS_SB_NODE, UBIFS_SB_NODE_SZ,
+ UBIFS_SB_LNUM, 0);
+ if (err) {
+ kfree(sup);
+ return ERR_PTR(err);
+ }
+
+ return sup;
+}
+
+/**
+ * ubifs_write_sb_node - write superblock node.
+ * @c: UBIFS file-system description object
+ * @sup: superblock node read with 'ubifs_read_sb_node()'
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_write_sb_node(struct ubifs_info *c, struct ubifs_sb_node *sup)
+{
+ int len = ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size);
+
+ ubifs_prepare_node(c, sup, UBIFS_SB_NODE_SZ, 1);
+ return ubifs_leb_change(c, UBIFS_SB_LNUM, sup, len, UBI_LONGTERM);
+}
+
+/**
+ * ubifs_read_superblock - read superblock.
+ * @c: UBIFS file-system description object
+ *
+ * This function finds, reads and checks the superblock. If an empty UBI volume
+ * is being mounted, this function creates default superblock. Returns zero in
+ * case of success, and a negative error code in case of failure.
+ */
+int ubifs_read_superblock(struct ubifs_info *c)
+{
+ int err, sup_flags;
+ struct ubifs_sb_node *sup;
+
+ if (c->empty) {
+ err = create_default_filesystem(c);
+ if (err)
+ return err;
+ }
+
+ sup = ubifs_read_sb_node(c);
+ if (IS_ERR(sup))
+ return PTR_ERR(sup);
+
+ /*
+ * The software supports all previous versions but not future versions,
+ * due to the unavailability of time-travelling equipment.
+ */
+ c->fmt_version = le32_to_cpu(sup->fmt_version);
+ if (c->fmt_version > UBIFS_FORMAT_VERSION) {
+ ubifs_err("on-flash format version is %d, but software only "
+ "supports up to version %d", c->fmt_version,
+ UBIFS_FORMAT_VERSION);
+ err = -EINVAL;
+ goto out;
+ }
+
+ if (c->fmt_version < 3) {
+ ubifs_err("on-flash format version %d is not supported",
+ c->fmt_version);
+ err = -EINVAL;
+ goto out;
+ }
+
+ switch (sup->key_hash) {
+ case UBIFS_KEY_HASH_R5:
+ c->key_hash = key_r5_hash;
+ c->key_hash_type = UBIFS_KEY_HASH_R5;
+ break;
+
+ case UBIFS_KEY_HASH_TEST:
+ c->key_hash = key_test_hash;
+ c->key_hash_type = UBIFS_KEY_HASH_TEST;
+ break;
+ };
+
+ c->key_fmt = sup->key_fmt;
+
+ switch (c->key_fmt) {
+ case UBIFS_SIMPLE_KEY_FMT:
+ c->key_len = UBIFS_SK_LEN;
+ break;
+ default:
+ ubifs_err("unsupported key format");
+ err = -EINVAL;
+ goto out;
+ }
+
+ c->leb_cnt = le32_to_cpu(sup->leb_cnt);
+ c->max_leb_cnt = le32_to_cpu(sup->max_leb_cnt);
+ c->max_bud_bytes = le64_to_cpu(sup->max_bud_bytes);
+ c->log_lebs = le32_to_cpu(sup->log_lebs);
+ c->lpt_lebs = le32_to_cpu(sup->lpt_lebs);
+ c->orph_lebs = le32_to_cpu(sup->orph_lebs);
+ c->jhead_cnt = le32_to_cpu(sup->jhead_cnt) + NONDATA_JHEADS_CNT;
+ c->fanout = le32_to_cpu(sup->fanout);
+ c->lsave_cnt = le32_to_cpu(sup->lsave_cnt);
+ c->default_compr = le16_to_cpu(sup->default_compr);
+ c->rp_size = le64_to_cpu(sup->rp_size);
+ c->rp_uid = le32_to_cpu(sup->rp_uid);
+ c->rp_gid = le32_to_cpu(sup->rp_gid);
+ sup_flags = le32_to_cpu(sup->flags);
+
+ c->vfs_sb->s_time_gran = le32_to_cpu(sup->time_gran);
+
+ memcpy(&c->uuid, &sup->uuid, 16);
+
+ c->big_lpt = !!(sup_flags & UBIFS_FLG_BIGLPT);
+
+ /* Automatically increase file system size to the maximum size */
+ c->old_leb_cnt = c->leb_cnt;
+ if (c->leb_cnt < c->vi.size && c->leb_cnt < c->max_leb_cnt) {
+ c->leb_cnt = min_t(int, c->max_leb_cnt, c->vi.size);
+ if (c->vfs_sb->s_flags & MS_RDONLY)
+ dbg_mnt("Auto resizing (ro) from %d LEBs to %d LEBs",
+ c->old_leb_cnt, c->leb_cnt);
+ else {
+ dbg_mnt("Auto resizing (sb) from %d LEBs to %d LEBs",
+ c->old_leb_cnt, c->leb_cnt);
+ sup->leb_cnt = cpu_to_le32(c->leb_cnt);
+ err = ubifs_write_sb_node(c, sup);
+ if (err)
+ goto out;
+ c->old_leb_cnt = c->leb_cnt;
+ }
+ }
+
+ c->log_bytes = (long long)c->log_lebs * c->leb_size;
+ c->log_last = UBIFS_LOG_LNUM + c->log_lebs - 1;
+ c->lpt_first = UBIFS_LOG_LNUM + c->log_lebs;
+ c->lpt_last = c->lpt_first + c->lpt_lebs - 1;
+ c->orph_first = c->lpt_last + 1;
+ c->orph_last = c->orph_first + c->orph_lebs - 1;
+ c->main_lebs = c->leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS;
+ c->main_lebs -= c->log_lebs + c->lpt_lebs + c->orph_lebs;
+ c->main_first = c->leb_cnt - c->main_lebs;
+ c->report_rp_size = ubifs_reported_space(c, c->rp_size);
+
+ err = validate_sb(c, sup);
+out:
+ kfree(sup);
+ return err;
+}
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ * Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file implements the scan which is a general-purpose function for
+ * determining what nodes are in an eraseblock. The scan is used to replay the
+ * journal, to do garbage collection. for the TNC in-the-gaps method, and by
+ * debugging functions.
+ */
+
+#include "ubifs.h"
+
+/**
+ * scan_padding_bytes - scan for padding bytes.
+ * @buf: buffer to scan
+ * @len: length of buffer
+ *
+ * This function returns the number of padding bytes on success and
+ * %SCANNED_GARBAGE on failure.
+ */
+static int scan_padding_bytes(void *buf, int len)
+{
+ int pad_len = 0, max_pad_len = min_t(int, UBIFS_PAD_NODE_SZ, len);
+ uint8_t *p = buf;
+
+ dbg_scan("not a node");
+
+ while (pad_len < max_pad_len && *p++ == UBIFS_PADDING_BYTE)
+ pad_len += 1;
+
+ if (!pad_len || (pad_len & 7))
+ return SCANNED_GARBAGE;
+
+ dbg_scan("%d padding bytes", pad_len);
+
+ return pad_len;
+}
+
+/**
+ * ubifs_scan_a_node - scan for a node or padding.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to scan
+ * @len: length of buffer
+ * @lnum: logical eraseblock number
+ * @offs: offset within the logical eraseblock
+ * @quiet: print no messages
+ *
+ * This function returns a scanning code to indicate what was scanned.
+ */
+int ubifs_scan_a_node(const struct ubifs_info *c, void *buf, int len, int lnum,
+ int offs, int quiet)
+{
+ struct ubifs_ch *ch = buf;
+ uint32_t magic;
+
+ magic = le32_to_cpu(ch->magic);
+
+ if (magic == 0xFFFFFFFF) {
+ dbg_scan("hit empty space");
+ return SCANNED_EMPTY_SPACE;
+ }
+
+ if (magic != UBIFS_NODE_MAGIC)
+ return scan_padding_bytes(buf, len);
+
+ if (len < UBIFS_CH_SZ)
+ return SCANNED_GARBAGE;
+
+ dbg_scan("scanning %s", dbg_ntype(ch->node_type));
+
+ if (ubifs_check_node(c, buf, lnum, offs, quiet))
+ return SCANNED_A_CORRUPT_NODE;
+
+ if (ch->node_type == UBIFS_PAD_NODE) {
+ struct ubifs_pad_node *pad = buf;
+ int pad_len = le32_to_cpu(pad->pad_len);
+ int node_len = le32_to_cpu(ch->len);
+
+ /* Validate the padding node */
+ if (pad_len < 0 ||
+ offs + node_len + pad_len > c->leb_size) {
+ if (!quiet) {
+ ubifs_err("bad pad node at LEB %d:%d",
+ lnum, offs);
+ dbg_dump_node(c, pad);
+ }
+ return SCANNED_A_BAD_PAD_NODE;
+ }
+
+ /* Make the node pads to 8-byte boundary */
+ if ((node_len + pad_len) & 7) {
+ if (!quiet) {
+ dbg_err("bad padding length %d - %d",
+ offs, offs + node_len + pad_len);
+ }
+ return SCANNED_A_BAD_PAD_NODE;
+ }
+
+ dbg_scan("%d bytes padded, offset now %d",
+ pad_len, ALIGN(offs + node_len + pad_len, 8));
+
+ return node_len + pad_len;
+ }
+
+ return SCANNED_A_NODE;
+}
+
+/**
+ * ubifs_start_scan - create LEB scanning information at start of scan.
+ * @c: UBIFS file-system description object
+ * @lnum: logical eraseblock number
+ * @offs: offset to start at (usually zero)
+ * @sbuf: scan buffer (must be c->leb_size)
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+struct ubifs_scan_leb *ubifs_start_scan(const struct ubifs_info *c, int lnum,
+ int offs, void *sbuf)
+{
+ struct ubifs_scan_leb *sleb;
+ int err;
+
+ dbg_scan("scan LEB %d:%d", lnum, offs);
+
+ sleb = kzalloc(sizeof(struct ubifs_scan_leb), GFP_NOFS);
+ if (!sleb)
+ return ERR_PTR(-ENOMEM);
+
+ sleb->lnum = lnum;
+ INIT_LIST_HEAD(&sleb->nodes);
+ sleb->buf = sbuf;
+
+ err = ubi_read(c->ubi, lnum, sbuf + offs, offs, c->leb_size - offs);
+ if (err && err != -EBADMSG) {
+ ubifs_err("cannot read %d bytes from LEB %d:%d,"
+ " error %d", c->leb_size - offs, lnum, offs, err);
+ kfree(sleb);
+ return ERR_PTR(err);
+ }
+
+ if (err == -EBADMSG)
+ sleb->ecc = 1;
+
+ return sleb;
+}
+
+/**
+ * ubifs_end_scan - update LEB scanning information at end of scan.
+ * @c: UBIFS file-system description object
+ * @sleb: scanning information
+ * @lnum: logical eraseblock number
+ * @offs: offset to start at (usually zero)
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+void ubifs_end_scan(const struct ubifs_info *c, struct ubifs_scan_leb *sleb,
+ int lnum, int offs)
+{
+ lnum = lnum;
+ dbg_scan("stop scanning LEB %d at offset %d", lnum, offs);
+ ubifs_assert(offs % c->min_io_size == 0);
+
+ sleb->endpt = ALIGN(offs, c->min_io_size);
+}
+
+/**
+ * ubifs_add_snod - add a scanned node to LEB scanning information.
+ * @c: UBIFS file-system description object
+ * @sleb: scanning information
+ * @buf: buffer containing node
+ * @offs: offset of node on flash
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_add_snod(const struct ubifs_info *c, struct ubifs_scan_leb *sleb,
+ void *buf, int offs)
+{
+ struct ubifs_ch *ch = buf;
+ struct ubifs_ino_node *ino = buf;
+ struct ubifs_scan_node *snod;
+
+ snod = kzalloc(sizeof(struct ubifs_scan_node), GFP_NOFS);
+ if (!snod)
+ return -ENOMEM;
+
+ snod->sqnum = le64_to_cpu(ch->sqnum);
+ snod->type = ch->node_type;
+ snod->offs = offs;
+ snod->len = le32_to_cpu(ch->len);
+ snod->node = buf;
+
+ switch (ch->node_type) {
+ case UBIFS_INO_NODE:
+ case UBIFS_DENT_NODE:
+ case UBIFS_XENT_NODE:
+ case UBIFS_DATA_NODE:
+ case UBIFS_TRUN_NODE:
+ /*
+ * The key is in the same place in all keyed
+ * nodes.
+ */
+ key_read(c, &ino->key, &snod->key);
+ break;
+ }
+ list_add_tail(&snod->list, &sleb->nodes);
+ sleb->nodes_cnt += 1;
+ return 0;
+}
+
+/**
+ * ubifs_scanned_corruption - print information after UBIFS scanned corruption.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number of corruption
+ * @offs: offset of corruption
+ * @buf: buffer containing corruption
+ */
+void ubifs_scanned_corruption(const struct ubifs_info *c, int lnum, int offs,
+ void *buf)
+{
+ int len;
+
+ ubifs_err("corrupted data at LEB %d:%d", lnum, offs);
+ if (dbg_failure_mode)
+ return;
+ len = c->leb_size - offs;
+ if (len > 4096)
+ len = 4096;
+ dbg_err("first %d bytes from LEB %d:%d", len, lnum, offs);
+ print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 4, buf, len, 1);
+}
+
+/**
+ * ubifs_scan - scan a logical eraseblock.
+ * @c: UBIFS file-system description object
+ * @lnum: logical eraseblock number
+ * @offs: offset to start at (usually zero)
+ * @sbuf: scan buffer (must be c->leb_size)
+ *
+ * This function scans LEB number @lnum and returns complete information about
+ * its contents. Returns an error code in case of failure.
+ */
+struct ubifs_scan_leb *ubifs_scan(const struct ubifs_info *c, int lnum,
+ int offs, void *sbuf)
+{
+ void *buf = sbuf + offs;
+ int err, len = c->leb_size - offs;
+ struct ubifs_scan_leb *sleb;
+
+ sleb = ubifs_start_scan(c, lnum, offs, sbuf);
+ if (IS_ERR(sleb))
+ return sleb;
+
+ while (len >= 8) {
+ struct ubifs_ch *ch = buf;
+ int node_len, ret;
+
+ dbg_scan("look at LEB %d:%d (%d bytes left)",
+ lnum, offs, len);
+
+ cond_resched();
+
+ ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 0);
+
+ if (ret > 0) {
+ /* Padding bytes or a valid padding node */
+ offs += ret;
+ buf += ret;
+ len -= ret;
+ continue;
+ }
+
+ if (ret == SCANNED_EMPTY_SPACE)
+ /* Empty space is checked later */
+ break;
+
+ switch (ret) {
+ case SCANNED_GARBAGE:
+ dbg_err("garbage");
+ goto corrupted;
+ case SCANNED_A_NODE:
+ break;
+ case SCANNED_A_CORRUPT_NODE:
+ case SCANNED_A_BAD_PAD_NODE:
+ dbg_err("bad node");
+ goto corrupted;
+ default:
+ dbg_err("unknown");
+ goto corrupted;
+ }
+
+ err = ubifs_add_snod(c, sleb, buf, offs);
+ if (err)
+ goto error;
+
+ node_len = ALIGN(le32_to_cpu(ch->len), 8);
+ offs += node_len;
+ buf += node_len;
+ len -= node_len;
+ }
+
+ if (offs % c->min_io_size)
+ goto corrupted;
+
+ ubifs_end_scan(c, sleb, lnum, offs);
+
+ for (; len > 4; offs += 4, buf = buf + 4, len -= 4)
+ if (*(uint32_t *)buf != 0xffffffff)
+ break;
+ for (; len; offs++, buf++, len--)
+ if (*(uint8_t *)buf != 0xff) {
+ ubifs_err("corrupt empty space at LEB %d:%d",
+ lnum, offs);
+ goto corrupted;
+ }
+
+ return sleb;
+
+corrupted:
+ ubifs_scanned_corruption(c, lnum, offs, buf);
+ err = -EUCLEAN;
+error:
+ ubifs_err("LEB %d scanning failed", lnum);
+ ubifs_scan_destroy(sleb);
+ return ERR_PTR(err);
+}
+
+/**
+ * ubifs_scan_destroy - destroy LEB scanning information.
+ * @sleb: scanning information to free
+ */
+void ubifs_scan_destroy(struct ubifs_scan_leb *sleb)
+{
+ struct ubifs_scan_node *node;
+ struct list_head *head;
+
+ head = &sleb->nodes;
+ while (!list_empty(head)) {
+ node = list_entry(head->next, struct ubifs_scan_node, list);
+ list_del(&node->list);
+ kfree(node);
+ }
+ kfree(sleb);
+}
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ * Adrian Hunter
+ */
+
+/*
+ * This file implements UBIFS shrinker which evicts clean znodes from the TNC
+ * tree when Linux VM needs more RAM.
+ *
+ * We do not implement any LRU lists to find oldest znodes to free because it
+ * would add additional overhead to the file system fast paths. So the shrinker
+ * just walks the TNC tree when searching for znodes to free.
+ *
+ * If the root of a TNC sub-tree is clean and old enough, then the children are
+ * also clean and old enough. So the shrinker walks the TNC in level order and
+ * dumps entire sub-trees.
+ *
+ * The age of znodes is just the time-stamp when they were last looked at.
+ * The current shrinker first tries to evict old znodes, then young ones.
+ *
+ * Since the shrinker is global, it has to protect against races with FS
+ * un-mounts, which is done by the 'ubifs_infos_lock' and 'c->umount_mutex'.
+ */
+
+#include "ubifs.h"
+
+/* List of all UBIFS file-system instances */
+LIST_HEAD(ubifs_infos);
+
+/*
+ * We number each shrinker run and record the number on the ubifs_info structure
+ * so that we can easily work out which ubifs_info structures have already been
+ * done by the current run.
+ */
+static unsigned int shrinker_run_no;
+
+/* Protects 'ubifs_infos' list */
+DEFINE_SPINLOCK(ubifs_infos_lock);
+
+/* Global clean znode counter (for all mounted UBIFS instances) */
+atomic_long_t ubifs_clean_zn_cnt;
+
+/**
+ * shrink_tnc - shrink TNC tree.
+ * @c: UBIFS file-system description object
+ * @nr: number of znodes to free
+ * @age: the age of znodes to free
+ * @contention: if any contention, this is set to %1
+ *
+ * This function traverses TNC tree and frees clean znodes. It does not free
+ * clean znodes which younger then @age. Returns number of freed znodes.
+ */
+static int shrink_tnc(struct ubifs_info *c, int nr, int age, int *contention)
+{
+ int total_freed = 0;
+ struct ubifs_znode *znode, *zprev;
+ int time = get_seconds();
+
+ ubifs_assert(mutex_is_locked(&c->umount_mutex));
+ ubifs_assert(mutex_is_locked(&c->tnc_mutex));
+
+ if (!c->zroot.znode || atomic_long_read(&c->clean_zn_cnt) == 0)
+ return 0;
+
+ /*
+ * Traverse the TNC tree in levelorder manner, so that it is possible
+ * to destroy large sub-trees. Indeed, if a znode is old, then all its
+ * children are older or of the same age.
+ *
+ * Note, we are holding 'c->tnc_mutex', so we do not have to lock the
+ * 'c->space_lock' when _reading_ 'c->clean_zn_cnt', because it is
+ * changed only when the 'c->tnc_mutex' is held.
+ */
+ zprev = NULL;
+ znode = ubifs_tnc_levelorder_next(c->zroot.znode, NULL);
+ while (znode && total_freed < nr &&
+ atomic_long_read(&c->clean_zn_cnt) > 0) {
+ int freed;
+
+ /*
+ * If the znode is clean, but it is in the 'c->cnext' list, this
+ * means that this znode has just been written to flash as a
+ * part of commit and was marked clean. They will be removed
+ * from the list at end commit. We cannot change the list,
+ * because it is not protected by any mutex (design decision to
+ * make commit really independent and parallel to main I/O). So
+ * we just skip these znodes.
+ *
+ * Note, the 'clean_zn_cnt' counters are not updated until
+ * after the commit, so the UBIFS shrinker does not report
+ * the znodes which are in the 'c->cnext' list as freeable.
+ *
+ * Also note, if the root of a sub-tree is not in 'c->cnext',
+ * then the whole sub-tree is not in 'c->cnext' as well, so it
+ * is safe to dump whole sub-tree.
+ */
+
+ if (znode->cnext) {
+ /*
+ * Very soon these znodes will be removed from the list
+ * and become freeable.
+ */
+ *contention = 1;
+ } else if (!ubifs_zn_dirty(znode) &&
+ abs(time - znode->time) >= age) {
+ if (znode->parent)
+ znode->parent->zbranch[znode->iip].znode = NULL;
+ else
+ c->zroot.znode = NULL;
+
+ freed = ubifs_destroy_tnc_subtree(znode);
+ atomic_long_sub(freed, &ubifs_clean_zn_cnt);
+ atomic_long_sub(freed, &c->clean_zn_cnt);
+ ubifs_assert(atomic_long_read(&c->clean_zn_cnt) >= 0);
+ total_freed += freed;
+ znode = zprev;
+ }
+
+ if (unlikely(!c->zroot.znode))
+ break;
+
+ zprev = znode;
+ znode = ubifs_tnc_levelorder_next(c->zroot.znode, znode);
+ cond_resched();
+ }
+
+ return total_freed;
+}
+
+/**
+ * shrink_tnc_trees - shrink UBIFS TNC trees.
+ * @nr: number of znodes to free
+ * @age: the age of znodes to free
+ * @contention: if any contention, this is set to %1
+ *
+ * This function walks the list of mounted UBIFS file-systems and frees clean
+ * znodes which are older then @age, until at least @nr znodes are freed.
+ * Returns the number of freed znodes.
+ */
+static int shrink_tnc_trees(int nr, int age, int *contention)
+{
+ struct ubifs_info *c;
+ struct list_head *p;
+ unsigned int run_no;
+ int freed = 0;
+
+ spin_lock(&ubifs_infos_lock);
+ do {
+ run_no = ++shrinker_run_no;
+ } while (run_no == 0);
+ /* Iterate over all mounted UBIFS file-systems and try to shrink them */
+ p = ubifs_infos.next;
+ while (p != &ubifs_infos) {
+ c = list_entry(p, struct ubifs_info, infos_list);
+ /*
+ * We move the ones we do to the end of the list, so we stop
+ * when we see one we have already done.
+ */
+ if (c->shrinker_run_no == run_no)
+ break;
+ if (!mutex_trylock(&c->umount_mutex)) {
+ /* Some un-mount is in progress, try next FS */
+ *contention = 1;
+ p = p->next;
+ continue;
+ }
+ /*
+ * We're holding 'c->umount_mutex', so the file-system won't go
+ * away.
+ */
+ if (!mutex_trylock(&c->tnc_mutex)) {
+ mutex_unlock(&c->umount_mutex);
+ *contention = 1;
+ p = p->next;
+ continue;
+ }
+ spin_unlock(&ubifs_infos_lock);
+ /*
+ * OK, now we have TNC locked, the file-system cannot go away -
+ * it is safe to reap the cache.
+ */
+ c->shrinker_run_no = run_no;
+ freed += shrink_tnc(c, nr, age, contention);
+ mutex_unlock(&c->tnc_mutex);
+ spin_lock(&ubifs_infos_lock);
+ /* Get the next list element before we move this one */
+ p = p->next;
+ /*
+ * Move this one to the end of the list to provide some
+ * fairness.
+ */
+ list_del(&c->infos_list);
+ list_add_tail(&c->infos_list, &ubifs_infos);
+ mutex_unlock(&c->umount_mutex);
+ if (freed >= nr)
+ break;
+ }
+ spin_unlock(&ubifs_infos_lock);
+ return freed;
+}
+
+/**
+ * kick_a_thread - kick a background thread to start commit.
+ *
+ * This function kicks a background thread to start background commit. Returns
+ * %-1 if a thread was kicked or there is another reason to assume the memory
+ * will soon be freed or become freeable. If there are no dirty znodes, returns
+ * %0.
+ */
+static int kick_a_thread(void)
+{
+ int i;
+ struct ubifs_info *c;
+
+ /*
+ * Iterate over all mounted UBIFS file-systems and find out if there is
+ * already an ongoing commit operation there. If no, then iterate for
+ * the second time and initiate background commit.
+ */
+ spin_lock(&ubifs_infos_lock);
+ for (i = 0; i < 2; i++) {
+ list_for_each_entry(c, &ubifs_infos, infos_list) {
+ long dirty_zn_cnt;
+
+ if (!mutex_trylock(&c->umount_mutex)) {
+ /*
+ * Some un-mount is in progress, it will
+ * certainly free memory, so just return.
+ */
+ spin_unlock(&ubifs_infos_lock);
+ return -1;
+ }
+
+ dirty_zn_cnt = atomic_long_read(&c->dirty_zn_cnt);
+
+ if (!dirty_zn_cnt || c->cmt_state == COMMIT_BROKEN ||
+ c->ro_media) {
+ mutex_unlock(&c->umount_mutex);
+ continue;
+ }
+
+ if (c->cmt_state != COMMIT_RESTING) {
+ spin_unlock(&ubifs_infos_lock);
+ mutex_unlock(&c->umount_mutex);
+ return -1;
+ }
+
+ if (i == 1) {
+ list_del(&c->infos_list);
+ list_add_tail(&c->infos_list, &ubifs_infos);
+ spin_unlock(&ubifs_infos_lock);
+
+ ubifs_request_bg_commit(c);
+ mutex_unlock(&c->umount_mutex);
+ return -1;
+ }
+ mutex_unlock(&c->umount_mutex);
+ }
+ }
+ spin_unlock(&ubifs_infos_lock);
+
+ return 0;
+}
+
+int ubifs_shrinker(int nr, gfp_t gfp_mask)
+{
+ int freed, contention = 0;
+ long clean_zn_cnt = atomic_long_read(&ubifs_clean_zn_cnt);
+
+ if (nr == 0)
+ return clean_zn_cnt;
+
+ if (!clean_zn_cnt) {
+ /*
+ * No clean znodes, nothing to reap. All we can do in this case
+ * is to kick background threads to start commit, which will
+ * probably make clean znodes which, in turn, will be freeable.
+ * And we return -1 which means will make VM call us again
+ * later.
+ */
+ dbg_tnc("no clean znodes, kick a thread");
+ return kick_a_thread();
+ }
+
+ freed = shrink_tnc_trees(nr, OLD_ZNODE_AGE, &contention);
+ if (freed >= nr)
+ goto out;
+
+ dbg_tnc("not enough old znodes, try to free young ones");
+ freed += shrink_tnc_trees(nr - freed, YOUNG_ZNODE_AGE, &contention);
+ if (freed >= nr)
+ goto out;
+
+ dbg_tnc("not enough young znodes, free all");
+ freed += shrink_tnc_trees(nr - freed, 0, &contention);
+
+ if (!freed && contention) {
+ dbg_tnc("freed nothing, but contention");
+ return -1;
+ }
+
+out:
+ dbg_tnc("%d znodes were freed, requested %d", freed, nr);
+ return freed;
+}
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ * Adrian Hunter
+ */
+
+/*
+ * This file implements UBIFS initialization and VFS superblock operations. Some
+ * initialization stuff which is rather large and complex is placed at
+ * corresponding subsystems, but most of it is here.
+ */
+
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/ctype.h>
+#include <linux/random.h>
+#include <linux/kthread.h>
+#include <linux/parser.h>
+#include <linux/seq_file.h>
+#include <linux/mount.h>
+#include "ubifs.h"
+
+/* Slab cache for UBIFS inodes */
+struct kmem_cache *ubifs_inode_slab;
+
+/* UBIFS TNC shrinker description */
+static struct shrinker ubifs_shrinker_info = {
+ .shrink = ubifs_shrinker,
+ .seeks = DEFAULT_SEEKS,
+};
+
+/**
+ * validate_inode - validate inode.
+ * @c: UBIFS file-system description object
+ * @inode: the inode to validate
+ *
+ * This is a helper function for 'ubifs_iget()' which validates various fields
+ * of a newly built inode to make sure they contain sane values and prevent
+ * possible vulnerabilities. Returns zero if the inode is all right and
+ * a non-zero error code if not.
+ */
+static int validate_inode(struct ubifs_info *c, const struct inode *inode)
+{
+ int err;
+ const struct ubifs_inode *ui = ubifs_inode(inode);
+
+ if (inode->i_size > c->max_inode_sz) {
+ ubifs_err("inode is too large (%lld)",
+ (long long)inode->i_size);
+ return 1;
+ }
+
+ if (ui->compr_type < 0 || ui->compr_type >= UBIFS_COMPR_TYPES_CNT) {
+ ubifs_err("unknown compression type %d", ui->compr_type);
+ return 2;
+ }
+
+ if (ui->xattr_names + ui->xattr_cnt > XATTR_LIST_MAX)
+ return 3;
+
+ if (ui->data_len < 0 || ui->data_len > UBIFS_MAX_INO_DATA)
+ return 4;
+
+ if (ui->xattr && (inode->i_mode & S_IFMT) != S_IFREG)
+ return 5;
+
+ if (!ubifs_compr_present(ui->compr_type)) {
+ ubifs_warn("inode %lu uses '%s' compression, but it was not "
+ "compiled in", inode->i_ino,
+ ubifs_compr_name(ui->compr_type));
+ }
+
+ err = dbg_check_dir_size(c, inode);
+ return err;
+}
+
+struct inode *ubifs_iget(struct super_block *sb, unsigned long inum)
+{
+ int err;
+ union ubifs_key key;
+ struct ubifs_ino_node *ino;
+ struct ubifs_info *c = sb->s_fs_info;
+ struct inode *inode;
+ struct ubifs_inode *ui;
+
+ dbg_gen("inode %lu", inum);
+
+ inode = iget_locked(sb, inum);
+ if (!inode)
+ return ERR_PTR(-ENOMEM);
+ if (!(inode->i_state & I_NEW))
+ return inode;
+ ui = ubifs_inode(inode);
+
+ ino = kmalloc(UBIFS_MAX_INO_NODE_SZ, GFP_NOFS);
+ if (!ino) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ ino_key_init(c, &key, inode->i_ino);
+
+ err = ubifs_tnc_lookup(c, &key, ino);
+ if (err)
+ goto out_ino;
+
+ inode->i_flags |= (S_NOCMTIME | S_NOATIME);
+ inode->i_nlink = le32_to_cpu(ino->nlink);
+ inode->i_uid = le32_to_cpu(ino->uid);
+ inode->i_gid = le32_to_cpu(ino->gid);
+ inode->i_atime.tv_sec = (int64_t)le64_to_cpu(ino->atime_sec);
+ inode->i_atime.tv_nsec = le32_to_cpu(ino->atime_nsec);
+ inode->i_mtime.tv_sec = (int64_t)le64_to_cpu(ino->mtime_sec);
+ inode->i_mtime.tv_nsec = le32_to_cpu(ino->mtime_nsec);
+ inode->i_ctime.tv_sec = (int64_t)le64_to_cpu(ino->ctime_sec);
+ inode->i_ctime.tv_nsec = le32_to_cpu(ino->ctime_nsec);
+ inode->i_mode = le32_to_cpu(ino->mode);
+ inode->i_size = le64_to_cpu(ino->size);
+
+ ui->data_len = le32_to_cpu(ino->data_len);
+ ui->flags = le32_to_cpu(ino->flags);
+ ui->compr_type = le16_to_cpu(ino->compr_type);
+ ui->creat_sqnum = le64_to_cpu(ino->creat_sqnum);
+ ui->xattr_cnt = le32_to_cpu(ino->xattr_cnt);
+ ui->xattr_size = le32_to_cpu(ino->xattr_size);
+ ui->xattr_names = le32_to_cpu(ino->xattr_names);
+ ui->synced_i_size = ui->ui_size = inode->i_size;
+
+ ui->xattr = (ui->flags & UBIFS_XATTR_FL) ? 1 : 0;
+
+ err = validate_inode(c, inode);
+ if (err)
+ goto out_invalid;
+
+ /* Disable readahead */
+ inode->i_mapping->backing_dev_info = &c->bdi;
+
+ switch (inode->i_mode & S_IFMT) {
+ case S_IFREG:
+ inode->i_mapping->a_ops = &ubifs_file_address_operations;
+ inode->i_op = &ubifs_file_inode_operations;
+ inode->i_fop = &ubifs_file_operations;
+ if (ui->xattr) {
+ ui->data = kmalloc(ui->data_len + 1, GFP_NOFS);
+ if (!ui->data) {
+ err = -ENOMEM;
+ goto out_ino;
+ }
+ memcpy(ui->data, ino->data, ui->data_len);
+ ((char *)ui->data)[ui->data_len] = '\0';
+ } else if (ui->data_len != 0) {
+ err = 10;
+ goto out_invalid;
+ }
+ break;
+ case S_IFDIR:
+ inode->i_op = &ubifs_dir_inode_operations;
+ inode->i_fop = &ubifs_dir_operations;
+ if (ui->data_len != 0) {
+ err = 11;
+ goto out_invalid;
+ }
+ break;
+ case S_IFLNK:
+ inode->i_op = &ubifs_symlink_inode_operations;
+ if (ui->data_len <= 0 || ui->data_len > UBIFS_MAX_INO_DATA) {
+ err = 12;
+ goto out_invalid;
+ }
+ ui->data = kmalloc(ui->data_len + 1, GFP_NOFS);
+ if (!ui->data) {
+ err = -ENOMEM;
+ goto out_ino;
+ }
+ memcpy(ui->data, ino->data, ui->data_len);
+ ((char *)ui->data)[ui->data_len] = '\0';
+ break;
+ case S_IFBLK:
+ case S_IFCHR:
+ {
+ dev_t rdev;
+ union ubifs_dev_desc *dev;
+
+ ui->data = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
+ if (!ui->data) {
+ err = -ENOMEM;
+ goto out_ino;
+ }
+
+ dev = (union ubifs_dev_desc *)ino->data;
+ if (ui->data_len == sizeof(dev->new))
+ rdev = new_decode_dev(le32_to_cpu(dev->new));
+ else if (ui->data_len == sizeof(dev->huge))
+ rdev = huge_decode_dev(le64_to_cpu(dev->huge));
+ else {
+ err = 13;
+ goto out_invalid;
+ }
+ memcpy(ui->data, ino->data, ui->data_len);
+ inode->i_op = &ubifs_file_inode_operations;
+ init_special_inode(inode, inode->i_mode, rdev);
+ break;
+ }
+ case S_IFSOCK:
+ case S_IFIFO:
+ inode->i_op = &ubifs_file_inode_operations;
+ init_special_inode(inode, inode->i_mode, 0);
+ if (ui->data_len != 0) {
+ err = 14;
+ goto out_invalid;
+ }
+ break;
+ default:
+ err = 15;
+ goto out_invalid;
+ }
+
+ kfree(ino);
+ ubifs_set_inode_flags(inode);
+ unlock_new_inode(inode);
+ return inode;
+
+out_invalid:
+ ubifs_err("inode %lu validation failed, error %d", inode->i_ino, err);
+ dbg_dump_node(c, ino);
+ dbg_dump_inode(c, inode);
+ err = -EINVAL;
+out_ino:
+ kfree(ino);
+out:
+ ubifs_err("failed to read inode %lu, error %d", inode->i_ino, err);
+ iget_failed(inode);
+ return ERR_PTR(err);
+}
+
+static struct inode *ubifs_alloc_inode(struct super_block *sb)
+{
+ struct ubifs_inode *ui;
+
+ ui = kmem_cache_alloc(ubifs_inode_slab, GFP_NOFS);
+ if (!ui)
+ return NULL;
+
+ memset((void *)ui + sizeof(struct inode), 0,
+ sizeof(struct ubifs_inode) - sizeof(struct inode));
+ mutex_init(&ui->ui_mutex);
+ spin_lock_init(&ui->ui_lock);
+ return &ui->vfs_inode;
+};
+
+static void ubifs_destroy_inode(struct inode *inode)
+{
+ struct ubifs_inode *ui = ubifs_inode(inode);
+
+ kfree(ui->data);
+ kmem_cache_free(ubifs_inode_slab, inode);
+}
+
+/*
+ * Note, Linux write-back code calls this without 'i_mutex'.
+ */
+static int ubifs_write_inode(struct inode *inode, int wait)
+{
+ int err;
+ struct ubifs_info *c = inode->i_sb->s_fs_info;
+ struct ubifs_inode *ui = ubifs_inode(inode);
+
+ ubifs_assert(!ui->xattr);
+ if (is_bad_inode(inode))
+ return 0;
+
+ mutex_lock(&ui->ui_mutex);
+ /*
+ * Due to races between write-back forced by budgeting
+ * (see 'sync_some_inodes()') and pdflush write-back, the inode may
+ * have already been synchronized, do not do this again. This might
+ * also happen if it was synchronized in an VFS operation, e.g.
+ * 'ubifs_link()'.
+ */
+ if (!ui->dirty) {
+ mutex_unlock(&ui->ui_mutex);
+ return 0;
+ }
+
+ dbg_gen("inode %lu", inode->i_ino);
+ err = ubifs_jnl_write_inode(c, inode, 0);
+ if (err)
+ ubifs_err("can't write inode %lu, error %d", inode->i_ino, err);
+
+ ui->dirty = 0;
+ mutex_unlock(&ui->ui_mutex);
+ ubifs_release_dirty_inode_budget(c, ui);
+ return err;
+}
+
+static void ubifs_delete_inode(struct inode *inode)
+{
+ int err;
+ struct ubifs_info *c = inode->i_sb->s_fs_info;
+
+ if (ubifs_inode(inode)->xattr)
+ /*
+ * Extended attribute inode deletions are fully handled in
+ * 'ubifs_removexattr()'. These inodes are special and have
+ * limited usage, so there is nothing to do here.
+ */
+ goto out;
+
+ dbg_gen("inode %lu", inode->i_ino);
+ ubifs_assert(!atomic_read(&inode->i_count));
+ ubifs_assert(inode->i_nlink == 0);
+
+ truncate_inode_pages(&inode->i_data, 0);
+ if (is_bad_inode(inode))
+ goto out;
+
+ ubifs_inode(inode)->ui_size = inode->i_size = 0;
+ err = ubifs_jnl_write_inode(c, inode, 1);
+ if (err)
+ /*
+ * Worst case we have a lost orphan inode wasting space, so a
+ * simple error message is ok here.
+ */
+ ubifs_err("can't write inode %lu, error %d", inode->i_ino, err);
+out:
+ clear_inode(inode);
+}
+
+static void ubifs_dirty_inode(struct inode *inode)
+{
+ struct ubifs_inode *ui = ubifs_inode(inode);
+
+ ubifs_assert(mutex_is_locked(&ui->ui_mutex));
+ if (!ui->dirty) {
+ ui->dirty = 1;
+ dbg_gen("inode %lu", inode->i_ino);
+ }
+}
+
+static int ubifs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+ struct ubifs_info *c = dentry->d_sb->s_fs_info;
+ unsigned long long free;
+
+ free = ubifs_budg_get_free_space(c);
+ dbg_gen("free space %lld bytes (%lld blocks)",
+ free, free >> UBIFS_BLOCK_SHIFT);
+
+ buf->f_type = UBIFS_SUPER_MAGIC;
+ buf->f_bsize = UBIFS_BLOCK_SIZE;
+ buf->f_blocks = c->block_cnt;
+ buf->f_bfree = free >> UBIFS_BLOCK_SHIFT;
+ if (free > c->report_rp_size)
+ buf->f_bavail = (free - c->report_rp_size) >> UBIFS_BLOCK_SHIFT;
+ else
+ buf->f_bavail = 0;
+ buf->f_files = 0;
+ buf->f_ffree = 0;
+ buf->f_namelen = UBIFS_MAX_NLEN;
+
+ return 0;
+}
+
+static int ubifs_show_options(struct seq_file *s, struct vfsmount *mnt)
+{
+ struct ubifs_info *c = mnt->mnt_sb->s_fs_info;
+
+ if (c->mount_opts.unmount_mode == 2)
+ seq_printf(s, ",fast_unmount");
+ else if (c->mount_opts.unmount_mode == 1)
+ seq_printf(s, ",norm_unmount");
+
+ return 0;
+}
+
+static int ubifs_sync_fs(struct super_block *sb, int wait)
+{
+ struct ubifs_info *c = sb->s_fs_info;
+ int i, ret = 0, err;
+
+ if (c->jheads)
+ for (i = 0; i < c->jhead_cnt; i++) {
+ err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
+ if (err && !ret)
+ ret = err;
+ }
+ /*
+ * We ought to call sync for c->ubi but it does not have one. If it had
+ * it would in turn call mtd->sync, however mtd operations are
+ * synchronous anyway, so we don't lose any sleep here.
+ */
+ return ret;
+}
+
+/**
+ * init_constants_early - initialize UBIFS constants.
+ * @c: UBIFS file-system description object
+ *
+ * This function initialize UBIFS constants which do not need the superblock to
+ * be read. It also checks that the UBI volume satisfies basic UBIFS
+ * requirements. Returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int init_constants_early(struct ubifs_info *c)
+{
+ if (c->vi.corrupted) {
+ ubifs_warn("UBI volume is corrupted - read-only mode");
+ c->ro_media = 1;
+ }
+
+ if (c->di.ro_mode) {
+ ubifs_msg("read-only UBI device");
+ c->ro_media = 1;
+ }
+
+ if (c->vi.vol_type == UBI_STATIC_VOLUME) {
+ ubifs_msg("static UBI volume - read-only mode");
+ c->ro_media = 1;
+ }
+
+ c->leb_cnt = c->vi.size;
+ c->leb_size = c->vi.usable_leb_size;
+ c->half_leb_size = c->leb_size / 2;
+ c->min_io_size = c->di.min_io_size;
+ c->min_io_shift = fls(c->min_io_size) - 1;
+
+ if (c->leb_size < UBIFS_MIN_LEB_SZ) {
+ ubifs_err("too small LEBs (%d bytes), min. is %d bytes",
+ c->leb_size, UBIFS_MIN_LEB_SZ);
+ return -EINVAL;
+ }
+
+ if (c->leb_cnt < UBIFS_MIN_LEB_CNT) {
+ ubifs_err("too few LEBs (%d), min. is %d",
+ c->leb_cnt, UBIFS_MIN_LEB_CNT);
+ return -EINVAL;
+ }
+
+ if (!is_power_of_2(c->min_io_size)) {
+ ubifs_err("bad min. I/O size %d", c->min_io_size);
+ return -EINVAL;
+ }
+
+ /*
+ * UBIFS aligns all node to 8-byte boundary, so to make function in
+ * io.c simpler, assume minimum I/O unit size to be 8 bytes if it is
+ * less than 8.
+ */
+ if (c->min_io_size < 8) {
+ c->min_io_size = 8;
+ c->min_io_shift = 3;
+ }
+
+ c->ref_node_alsz = ALIGN(UBIFS_REF_NODE_SZ, c->min_io_size);
+ c->mst_node_alsz = ALIGN(UBIFS_MST_NODE_SZ, c->min_io_size);
+
+ /*
+ * Initialize node length ranges which are mostly needed for node
+ * length validation.
+ */
+ c->ranges[UBIFS_PAD_NODE].len = UBIFS_PAD_NODE_SZ;
+ c->ranges[UBIFS_SB_NODE].len = UBIFS_SB_NODE_SZ;
+ c->ranges[UBIFS_MST_NODE].len = UBIFS_MST_NODE_SZ;
+ c->ranges[UBIFS_REF_NODE].len = UBIFS_REF_NODE_SZ;
+ c->ranges[UBIFS_TRUN_NODE].len = UBIFS_TRUN_NODE_SZ;
+ c->ranges[UBIFS_CS_NODE].len = UBIFS_CS_NODE_SZ;
+
+ c->ranges[UBIFS_INO_NODE].min_len = UBIFS_INO_NODE_SZ;
+ c->ranges[UBIFS_INO_NODE].max_len = UBIFS_MAX_INO_NODE_SZ;
+ c->ranges[UBIFS_ORPH_NODE].min_len =
+ UBIFS_ORPH_NODE_SZ + sizeof(__le64);
+ c->ranges[UBIFS_ORPH_NODE].max_len = c->leb_size;
+ c->ranges[UBIFS_DENT_NODE].min_len = UBIFS_DENT_NODE_SZ;
+ c->ranges[UBIFS_DENT_NODE].max_len = UBIFS_MAX_DENT_NODE_SZ;
+ c->ranges[UBIFS_XENT_NODE].min_len = UBIFS_XENT_NODE_SZ;
+ c->ranges[UBIFS_XENT_NODE].max_len = UBIFS_MAX_XENT_NODE_SZ;
+ c->ranges[UBIFS_DATA_NODE].min_len = UBIFS_DATA_NODE_SZ;
+ c->ranges[UBIFS_DATA_NODE].max_len = UBIFS_MAX_DATA_NODE_SZ;
+ /*
+ * Minimum indexing node size is amended later when superblock is
+ * read and the key length is known.
+ */
+ c->ranges[UBIFS_IDX_NODE].min_len = UBIFS_IDX_NODE_SZ + UBIFS_BRANCH_SZ;
+ /*
+ * Maximum indexing node size is amended later when superblock is
+ * read and the fanout is known.
+ */
+ c->ranges[UBIFS_IDX_NODE].max_len = INT_MAX;
+
+ /*
+ * Initialize dead and dark LEB space watermarks.
+ *
+ * Dead space is the space which cannot be used. Its watermark is
+ * equivalent to min. I/O unit or minimum node size if it is greater
+ * then min. I/O unit.
+ *
+ * Dark space is the space which might be used, or might not, depending
+ * on which node should be written to the LEB. Its watermark is
+ * equivalent to maximum UBIFS node size.
+ */
+ c->dead_wm = ALIGN(MIN_WRITE_SZ, c->min_io_size);
+ c->dark_wm = ALIGN(UBIFS_MAX_NODE_SZ, c->min_io_size);
+
+ return 0;
+}
+
+/**
+ * bud_wbuf_callback - bud LEB write-buffer synchronization call-back.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB the write-buffer was synchronized to
+ * @free: how many free bytes left in this LEB
+ * @pad: how many bytes were padded
+ *
+ * This is a callback function which is called by the I/O unit when the
+ * write-buffer is synchronized. We need this to correctly maintain space
+ * accounting in bud logical eraseblocks. This function returns zero in case of
+ * success and a negative error code in case of failure.
+ *
+ * This function actually belongs to the journal, but we keep it here because
+ * we want to keep it static.
+ */
+static int bud_wbuf_callback(struct ubifs_info *c, int lnum, int free, int pad)
+{
+ return ubifs_update_one_lp(c, lnum, free, pad, 0, 0);
+}
+
+/*
+ * init_constants_late - initialize UBIFS constants.
+ * @c: UBIFS file-system description object
+ *
+ * This is a helper function which initializes various UBIFS constants after
+ * the superblock has been read. It also checks various UBIFS parameters and
+ * makes sure they are all right. Returns zero in case of success and a
+ * negative error code in case of failure.
+ */
+static int init_constants_late(struct ubifs_info *c)
+{
+ int tmp, err;
+ uint64_t tmp64;
+
+ c->main_bytes = (long long)c->main_lebs * c->leb_size;
+ c->max_znode_sz = sizeof(struct ubifs_znode) +
+ c->fanout * sizeof(struct ubifs_zbranch);
+
+ tmp = ubifs_idx_node_sz(c, 1);
+ c->ranges[UBIFS_IDX_NODE].min_len = tmp;
+ c->min_idx_node_sz = ALIGN(tmp, 8);
+
+ tmp = ubifs_idx_node_sz(c, c->fanout);
+ c->ranges[UBIFS_IDX_NODE].max_len = tmp;
+ c->max_idx_node_sz = ALIGN(tmp, 8);
+
+ /* Make sure LEB size is large enough to fit full commit */
+ tmp = UBIFS_CS_NODE_SZ + UBIFS_REF_NODE_SZ * c->jhead_cnt;
+ tmp = ALIGN(tmp, c->min_io_size);
+ if (tmp > c->leb_size) {
+ dbg_err("too small LEB size %d, at least %d needed",
+ c->leb_size, tmp);
+ return -EINVAL;
+ }
+
+ /*
+ * Make sure that the log is large enough to fit reference nodes for
+ * all buds plus one reserved LEB.
+ */
+ tmp64 = c->max_bud_bytes;
+ tmp = do_div(tmp64, c->leb_size);
+ c->max_bud_cnt = tmp64 + !!tmp;
+ tmp = (c->ref_node_alsz * c->max_bud_cnt + c->leb_size - 1);
+ tmp /= c->leb_size;
+ tmp += 1;
+ if (c->log_lebs < tmp) {
+ dbg_err("too small log %d LEBs, required min. %d LEBs",
+ c->log_lebs, tmp);
+ return -EINVAL;
+ }
+
+ /*
+ * When budgeting we assume worst-case scenarios when the pages are not
+ * be compressed and direntries are of the maximum size.
+ *
+ * Note, data, which may be stored in inodes is budgeted separately, so
+ * it is not included into 'c->inode_budget'.
+ */
+ c->page_budget = UBIFS_MAX_DATA_NODE_SZ * UBIFS_BLOCKS_PER_PAGE;
+ c->inode_budget = UBIFS_INO_NODE_SZ;
+ c->dent_budget = UBIFS_MAX_DENT_NODE_SZ;
+
+ /*
+ * When the amount of flash space used by buds becomes
+ * 'c->max_bud_bytes', UBIFS just blocks all writers and starts commit.
+ * The writers are unblocked when the commit is finished. To avoid
+ * writers to be blocked UBIFS initiates background commit in advance,
+ * when number of bud bytes becomes above the limit defined below.
+ */
+ c->bg_bud_bytes = (c->max_bud_bytes * 13) >> 4;
+
+ /*
+ * Ensure minimum journal size. All the bytes in the journal heads are
+ * considered to be used, when calculating the current journal usage.
+ * Consequently, if the journal is too small, UBIFS will treat it as
+ * always full.
+ */
+ tmp64 = (uint64_t)(c->jhead_cnt + 1) * c->leb_size + 1;
+ if (c->bg_bud_bytes < tmp64)
+ c->bg_bud_bytes = tmp64;
+ if (c->max_bud_bytes < tmp64 + c->leb_size)
+ c->max_bud_bytes = tmp64 + c->leb_size;
+
+ err = ubifs_calc_lpt_geom(c);
+ if (err)
+ return err;
+
+ c->min_idx_lebs = ubifs_calc_min_idx_lebs(c);
+
+ /*
+ * Calculate total amount of FS blocks. This number is not used
+ * internally because it does not make much sense for UBIFS, but it is
+ * necessary to report something for the 'statfs()' call.
+ *
+ * Subtract the LEB reserved for GC and the LEB which is reserved for
+ * deletions.
+ *
+ * Review 'ubifs_calc_available()' if changing this calculation.
+ */
+ tmp64 = c->main_lebs - 2;
+ tmp64 *= (uint64_t)c->leb_size - c->dark_wm;
+ tmp64 = ubifs_reported_space(c, tmp64);
+ c->block_cnt = tmp64 >> UBIFS_BLOCK_SHIFT;
+
+ return 0;
+}
+
+/**
+ * take_gc_lnum - reserve GC LEB.
+ * @c: UBIFS file-system description object
+ *
+ * This function ensures that the LEB reserved for garbage collection is
+ * unmapped and is marked as "taken" in lprops. We also have to set free space
+ * to LEB size and dirty space to zero, because lprops may contain out-of-date
+ * information if the file-system was un-mounted before it has been committed.
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int take_gc_lnum(struct ubifs_info *c)
+{
+ int err;
+
+ if (c->gc_lnum == -1) {
+ ubifs_err("no LEB for GC");
+ return -EINVAL;
+ }
+
+ err = ubifs_leb_unmap(c, c->gc_lnum);
+ if (err)
+ return err;
+
+ /* And we have to tell lprops that this LEB is taken */
+ err = ubifs_change_one_lp(c, c->gc_lnum, c->leb_size, 0,
+ LPROPS_TAKEN, 0, 0);
+ return err;
+}
+
+/**
+ * alloc_wbufs - allocate write-buffers.
+ * @c: UBIFS file-system description object
+ *
+ * This helper function allocates and initializes UBIFS write-buffers. Returns
+ * zero in case of success and %-ENOMEM in case of failure.
+ */
+static int alloc_wbufs(struct ubifs_info *c)
+{
+ int i, err;
+
+ c->jheads = kzalloc(c->jhead_cnt * sizeof(struct ubifs_jhead),
+ GFP_KERNEL);
+ if (!c->jheads)
+ return -ENOMEM;
+
+ /* Initialize journal heads */
+ for (i = 0; i < c->jhead_cnt; i++) {
+ INIT_LIST_HEAD(&c->jheads[i].buds_list);
+ err = ubifs_wbuf_init(c, &c->jheads[i].wbuf);
+ if (err)
+ return err;
+
+ c->jheads[i].wbuf.sync_callback = &bud_wbuf_callback;
+ c->jheads[i].wbuf.jhead = i;
+ }
+
+ c->jheads[BASEHD].wbuf.dtype = UBI_SHORTTERM;
+ /*
+ * Garbage Collector head likely contains long-term data and
+ * does not need to be synchronized by timer.
+ */
+ c->jheads[GCHD].wbuf.dtype = UBI_LONGTERM;
+ c->jheads[GCHD].wbuf.timeout = 0;
+
+ return 0;
+}
+
+/**
+ * free_wbufs - free write-buffers.
+ * @c: UBIFS file-system description object
+ */
+static void free_wbufs(struct ubifs_info *c)
+{
+ int i;
+
+ if (c->jheads) {
+ for (i = 0; i < c->jhead_cnt; i++) {
+ kfree(c->jheads[i].wbuf.buf);
+ kfree(c->jheads[i].wbuf.inodes);
+ }
+ kfree(c->jheads);
+ c->jheads = NULL;
+ }
+}
+
+/**
+ * free_orphans - free orphans.
+ * @c: UBIFS file-system description object
+ */
+static void free_orphans(struct ubifs_info *c)
+{
+ struct ubifs_orphan *orph;
+
+ while (c->orph_dnext) {
+ orph = c->orph_dnext;
+ c->orph_dnext = orph->dnext;
+ list_del(&orph->list);
+ kfree(orph);
+ }
+
+ while (!list_empty(&c->orph_list)) {
+ orph = list_entry(c->orph_list.next, struct ubifs_orphan, list);
+ list_del(&orph->list);
+ kfree(orph);
+ dbg_err("orphan list not empty at unmount");
+ }
+
+ vfree(c->orph_buf);
+ c->orph_buf = NULL;
+}
+
+/**
+ * free_buds - free per-bud objects.
+ * @c: UBIFS file-system description object
+ */
+static void free_buds(struct ubifs_info *c)
+{
+ struct rb_node *this = c->buds.rb_node;
+ struct ubifs_bud *bud;
+
+ while (this) {
+ if (this->rb_left)
+ this = this->rb_left;
+ else if (this->rb_right)
+ this = this->rb_right;
+ else {
+ bud = rb_entry(this, struct ubifs_bud, rb);
+ this = rb_parent(this);
+ if (this) {
+ if (this->rb_left == &bud->rb)
+ this->rb_left = NULL;
+ else
+ this->rb_right = NULL;
+ }
+ kfree(bud);
+ }
+ }
+}
+
+/**
+ * check_volume_empty - check if the UBI volume is empty.
+ * @c: UBIFS file-system description object
+ *
+ * This function checks if the UBIFS volume is empty by looking if its LEBs are
+ * mapped or not. The result of checking is stored in the @c->empty variable.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+static int check_volume_empty(struct ubifs_info *c)
+{
+ int lnum, err;
+
+ c->empty = 1;
+ for (lnum = 0; lnum < c->leb_cnt; lnum++) {
+ err = ubi_is_mapped(c->ubi, lnum);
+ if (unlikely(err < 0))
+ return err;
+ if (err == 1) {
+ c->empty = 0;
+ break;
+ }
+
+ cond_resched();
+ }
+
+ return 0;
+}
+
+/*
+ * UBIFS mount options.
+ *
+ * Opt_fast_unmount: do not run a journal commit before un-mounting
+ * Opt_norm_unmount: run a journal commit before un-mounting
+ * Opt_err: just end of array marker
+ */
+enum {
+ Opt_fast_unmount,
+ Opt_norm_unmount,
+ Opt_err,
+};
+
+static match_table_t tokens = {
+ {Opt_fast_unmount, "fast_unmount"},
+ {Opt_norm_unmount, "norm_unmount"},
+ {Opt_err, NULL},
+};
+
+/**
+ * ubifs_parse_options - parse mount parameters.
+ * @c: UBIFS file-system description object
+ * @options: parameters to parse
+ * @is_remount: non-zero if this is FS re-mount
+ *
+ * This function parses UBIFS mount options and returns zero in case success
+ * and a negative error code in case of failure.
+ */
+static int ubifs_parse_options(struct ubifs_info *c, char *options,
+ int is_remount)
+{
+ char *p;
+ substring_t args[MAX_OPT_ARGS];
+
+ if (!options)
+ return 0;
+
+ while ((p = strsep(&options, ","))) {
+ int token;
+
+ if (!*p)
+ continue;
+
+ token = match_token(p, tokens, args);
+ switch (token) {
+ case Opt_fast_unmount:
+ c->mount_opts.unmount_mode = 2;
+ c->fast_unmount = 1;
+ break;
+ case Opt_norm_unmount:
+ c->mount_opts.unmount_mode = 1;
+ c->fast_unmount = 0;
+ break;
+ default:
+ ubifs_err("unrecognized mount option \"%s\" "
+ "or missing value", p);
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * destroy_journal - destroy journal data structures.
+ * @c: UBIFS file-system description object
+ *
+ * This function destroys journal data structures including those that may have
+ * been created by recovery functions.
+ */
+static void destroy_journal(struct ubifs_info *c)
+{
+ while (!list_empty(&c->unclean_leb_list)) {
+ struct ubifs_unclean_leb *ucleb;
+
+ ucleb = list_entry(c->unclean_leb_list.next,
+ struct ubifs_unclean_leb, list);
+ list_del(&ucleb->list);
+ kfree(ucleb);
+ }
+ while (!list_empty(&c->old_buds)) {
+ struct ubifs_bud *bud;
+
+ bud = list_entry(c->old_buds.next, struct ubifs_bud, list);
+ list_del(&bud->list);
+ kfree(bud);
+ }
+ ubifs_destroy_idx_gc(c);
+ ubifs_destroy_size_tree(c);
+ ubifs_tnc_close(c);
+ free_buds(c);
+}
+
+/**
+ * mount_ubifs - mount UBIFS file-system.
+ * @c: UBIFS file-system description object
+ *
+ * This function mounts UBIFS file system. Returns zero in case of success and
+ * a negative error code in case of failure.
+ *
+ * Note, the function does not de-allocate resources it it fails half way
+ * through, and the caller has to do this instead.
+ */
+static int mount_ubifs(struct ubifs_info *c)
+{
+ struct super_block *sb = c->vfs_sb;
+ int err, mounted_read_only = (sb->s_flags & MS_RDONLY);
+ long long x;
+ size_t sz;
+
+ err = init_constants_early(c);
+ if (err)
+ return err;
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+ c->dbg_buf = vmalloc(c->leb_size);
+ if (!c->dbg_buf)
+ return -ENOMEM;
+#endif
+
+ err = check_volume_empty(c);
+ if (err)
+ goto out_free;
+
+ if (c->empty && (mounted_read_only || c->ro_media)) {
+ /*
+ * This UBI volume is empty, and read-only, or the file system
+ * is mounted read-only - we cannot format it.
+ */
+ ubifs_err("can't format empty UBI volume: read-only %s",
+ c->ro_media ? "UBI volume" : "mount");
+ err = -EROFS;
+ goto out_free;
+ }
+
+ if (c->ro_media && !mounted_read_only) {
+ ubifs_err("cannot mount read-write - read-only media");
+ err = -EROFS;
+ goto out_free;
+ }
+
+ /*
+ * The requirement for the buffer is that it should fit indexing B-tree
+ * height amount of integers. We assume the height if the TNC tree will
+ * never exceed 64.
+ */
+ err = -ENOMEM;
+ c->bottom_up_buf = kmalloc(BOTTOM_UP_HEIGHT * sizeof(int), GFP_KERNEL);
+ if (!c->bottom_up_buf)
+ goto out_free;
+
+ c->sbuf = vmalloc(c->leb_size);
+ if (!c->sbuf)
+ goto out_free;
+
+ if (!mounted_read_only) {
+ c->ileb_buf = vmalloc(c->leb_size);
+ if (!c->ileb_buf)
+ goto out_free;
+ }
+
+ err = ubifs_read_superblock(c);
+ if (err)
+ goto out_free;
+
+ /*
+ * Make sure the compressor which is set as the default on in the
+ * superblock was actually compiled in.
+ */
+ if (!ubifs_compr_present(c->default_compr)) {
+ ubifs_warn("'%s' compressor is set by superblock, but not "
+ "compiled in", ubifs_compr_name(c->default_compr));
+ c->default_compr = UBIFS_COMPR_NONE;
+ }
+
+ dbg_failure_mode_registration(c);
+
+ err = init_constants_late(c);
+ if (err)
+ goto out_dereg;
+
+ sz = ALIGN(c->max_idx_node_sz, c->min_io_size);
+ sz = ALIGN(sz + c->max_idx_node_sz, c->min_io_size);
+ c->cbuf = kmalloc(sz, GFP_NOFS);
+ if (!c->cbuf) {
+ err = -ENOMEM;
+ goto out_dereg;
+ }
+
+ if (!mounted_read_only) {
+ err = alloc_wbufs(c);
+ if (err)
+ goto out_cbuf;
+
+ /* Create background thread */
+ sprintf(c->bgt_name, BGT_NAME_PATTERN, c->vi.ubi_num,
+ c->vi.vol_id);
+ c->bgt = kthread_create(ubifs_bg_thread, c, c->bgt_name);
+ if (!c->bgt)
+ c->bgt = ERR_PTR(-EINVAL);
+ if (IS_ERR(c->bgt)) {
+ err = PTR_ERR(c->bgt);
+ c->bgt = NULL;
+ ubifs_err("cannot spawn \"%s\", error %d",
+ c->bgt_name, err);
+ goto out_wbufs;
+ }
+ wake_up_process(c->bgt);
+ }
+
+ err = ubifs_read_master(c);
+ if (err)
+ goto out_master;
+
+ if ((c->mst_node->flags & cpu_to_le32(UBIFS_MST_DIRTY)) != 0) {
+ ubifs_msg("recovery needed");
+ c->need_recovery = 1;
+ if (!mounted_read_only) {
+ err = ubifs_recover_inl_heads(c, c->sbuf);
+ if (err)
+ goto out_master;
+ }
+ } else if (!mounted_read_only) {
+ /*
+ * Set the "dirty" flag so that if we reboot uncleanly we
+ * will notice this immediately on the next mount.
+ */
+ c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
+ err = ubifs_write_master(c);
+ if (err)
+ goto out_master;
+ }
+
+ err = ubifs_lpt_init(c, 1, !mounted_read_only);
+ if (err)
+ goto out_lpt;
+
+ err = dbg_check_idx_size(c, c->old_idx_sz);
+ if (err)
+ goto out_lpt;
+
+ err = ubifs_replay_journal(c);
+ if (err)
+ goto out_journal;
+
+ err = ubifs_mount_orphans(c, c->need_recovery, mounted_read_only);
+ if (err)
+ goto out_orphans;
+
+ if (!mounted_read_only) {
+ int lnum;
+
+ /* Check for enough free space */
+ if (ubifs_calc_available(c, c->min_idx_lebs) <= 0) {
+ ubifs_err("insufficient available space");
+ err = -EINVAL;
+ goto out_orphans;
+ }
+
+ /* Check for enough log space */
+ lnum = c->lhead_lnum + 1;
+ if (lnum >= UBIFS_LOG_LNUM + c->log_lebs)
+ lnum = UBIFS_LOG_LNUM;
+ if (lnum == c->ltail_lnum) {
+ err = ubifs_consolidate_log(c);
+ if (err)
+ goto out_orphans;
+ }
+
+ if (c->need_recovery) {
+ err = ubifs_recover_size(c);
+ if (err)
+ goto out_orphans;
+ err = ubifs_rcvry_gc_commit(c);
+ } else
+ err = take_gc_lnum(c);
+ if (err)
+ goto out_orphans;
+
+ err = dbg_check_lprops(c);
+ if (err)
+ goto out_orphans;
+ } else if (c->need_recovery) {
+ err = ubifs_recover_size(c);
+ if (err)
+ goto out_orphans;
+ }
+
+ spin_lock(&ubifs_infos_lock);
+ list_add_tail(&c->infos_list, &ubifs_infos);
+ spin_unlock(&ubifs_infos_lock);
+
+ if (c->need_recovery) {
+ if (mounted_read_only)
+ ubifs_msg("recovery deferred");
+ else {
+ c->need_recovery = 0;
+ ubifs_msg("recovery completed");
+ }
+ }
+
+ err = dbg_check_filesystem(c);
+ if (err)
+ goto out_infos;
+
+ ubifs_msg("mounted UBI device %d, volume %d", c->vi.ubi_num,
+ c->vi.vol_id);
+ if (mounted_read_only)
+ ubifs_msg("mounted read-only");
+ x = (long long)c->main_lebs * c->leb_size;
+ ubifs_msg("file system size: %lld bytes (%lld KiB, %lld MiB, %d LEBs)",
+ x, x >> 10, x >> 20, c->main_lebs);
+ x = (long long)c->log_lebs * c->leb_size + c->max_bud_bytes;
+ ubifs_msg("journal size: %lld bytes (%lld KiB, %lld MiB, %d LEBs)",
+ x, x >> 10, x >> 20, c->log_lebs + c->max_bud_cnt);
+ ubifs_msg("default compressor: %s", ubifs_compr_name(c->default_compr));
+ ubifs_msg("media format %d, latest format %d",
+ c->fmt_version, UBIFS_FORMAT_VERSION);
+
+ dbg_msg("compiled on: " __DATE__ " at " __TIME__);
+ dbg_msg("min. I/O unit size: %d bytes", c->min_io_size);
+ dbg_msg("LEB size: %d bytes (%d KiB)",
+ c->leb_size, c->leb_size / 1024);
+ dbg_msg("data journal heads: %d",
+ c->jhead_cnt - NONDATA_JHEADS_CNT);
+ dbg_msg("UUID: %02X%02X%02X%02X-%02X%02X"
+ "-%02X%02X-%02X%02X-%02X%02X%02X%02X%02X%02X",
+ c->uuid[0], c->uuid[1], c->uuid[2], c->uuid[3],
+ c->uuid[4], c->uuid[5], c->uuid[6], c->uuid[7],
+ c->uuid[8], c->uuid[9], c->uuid[10], c->uuid[11],
+ c->uuid[12], c->uuid[13], c->uuid[14], c->uuid[15]);
+ dbg_msg("fast unmount: %d", c->fast_unmount);
+ dbg_msg("big_lpt %d", c->big_lpt);
+ dbg_msg("log LEBs: %d (%d - %d)",
+ c->log_lebs, UBIFS_LOG_LNUM, c->log_last);
+ dbg_msg("LPT area LEBs: %d (%d - %d)",
+ c->lpt_lebs, c->lpt_first, c->lpt_last);
+ dbg_msg("orphan area LEBs: %d (%d - %d)",
+ c->orph_lebs, c->orph_first, c->orph_last);
+ dbg_msg("main area LEBs: %d (%d - %d)",
+ c->main_lebs, c->main_first, c->leb_cnt - 1);
+ dbg_msg("index LEBs: %d", c->lst.idx_lebs);
+ dbg_msg("total index bytes: %lld (%lld KiB, %lld MiB)",
+ c->old_idx_sz, c->old_idx_sz >> 10, c->old_idx_sz >> 20);
+ dbg_msg("key hash type: %d", c->key_hash_type);
+ dbg_msg("tree fanout: %d", c->fanout);
+ dbg_msg("reserved GC LEB: %d", c->gc_lnum);
+ dbg_msg("first main LEB: %d", c->main_first);
+ dbg_msg("dead watermark: %d", c->dead_wm);
+ dbg_msg("dark watermark: %d", c->dark_wm);
+ x = (long long)c->main_lebs * c->dark_wm;
+ dbg_msg("max. dark space: %lld (%lld KiB, %lld MiB)",
+ x, x >> 10, x >> 20);
+ dbg_msg("maximum bud bytes: %lld (%lld KiB, %lld MiB)",
+ c->max_bud_bytes, c->max_bud_bytes >> 10,
+ c->max_bud_bytes >> 20);
+ dbg_msg("BG commit bud bytes: %lld (%lld KiB, %lld MiB)",
+ c->bg_bud_bytes, c->bg_bud_bytes >> 10,
+ c->bg_bud_bytes >> 20);
+ dbg_msg("current bud bytes %lld (%lld KiB, %lld MiB)",
+ c->bud_bytes, c->bud_bytes >> 10, c->bud_bytes >> 20);
+ dbg_msg("max. seq. number: %llu", c->max_sqnum);
+ dbg_msg("commit number: %llu", c->cmt_no);
+
+ return 0;
+
+out_infos:
+ spin_lock(&ubifs_infos_lock);
+ list_del(&c->infos_list);
+ spin_unlock(&ubifs_infos_lock);
+out_orphans:
+ free_orphans(c);
+out_journal:
+ destroy_journal(c);
+out_lpt:
+ ubifs_lpt_free(c, 0);
+out_master:
+ kfree(c->mst_node);
+ kfree(c->rcvrd_mst_node);
+ if (c->bgt)
+ kthread_stop(c->bgt);
+out_wbufs:
+ free_wbufs(c);
+out_cbuf:
+ kfree(c->cbuf);
+out_dereg:
+ dbg_failure_mode_deregistration(c);
+out_free:
+ vfree(c->ileb_buf);
+ vfree(c->sbuf);
+ kfree(c->bottom_up_buf);
+ UBIFS_DBG(vfree(c->dbg_buf));
+ return err;
+}
+
+/**
+ * ubifs_umount - un-mount UBIFS file-system.
+ * @c: UBIFS file-system description object
+ *
+ * Note, this function is called to free allocated resourced when un-mounting,
+ * as well as free resources when an error occurred while we were half way
+ * through mounting (error path cleanup function). So it has to make sure the
+ * resource was actually allocated before freeing it.
+ */
+static void ubifs_umount(struct ubifs_info *c)
+{
+ dbg_gen("un-mounting UBI device %d, volume %d", c->vi.ubi_num,
+ c->vi.vol_id);
+
+ spin_lock(&ubifs_infos_lock);
+ list_del(&c->infos_list);
+ spin_unlock(&ubifs_infos_lock);
+
+ if (c->bgt)
+ kthread_stop(c->bgt);
+
+ destroy_journal(c);
+ free_wbufs(c);
+ free_orphans(c);
+ ubifs_lpt_free(c, 0);
+
+ kfree(c->cbuf);
+ kfree(c->rcvrd_mst_node);
+ kfree(c->mst_node);
+ vfree(c->sbuf);
+ kfree(c->bottom_up_buf);
+ UBIFS_DBG(vfree(c->dbg_buf));
+ vfree(c->ileb_buf);
+ dbg_failure_mode_deregistration(c);
+}
+
+/**
+ * ubifs_remount_rw - re-mount in read-write mode.
+ * @c: UBIFS file-system description object
+ *
+ * UBIFS avoids allocating many unnecessary resources when mounted in read-only
+ * mode. This function allocates the needed resources and re-mounts UBIFS in
+ * read-write mode.
+ */
+static int ubifs_remount_rw(struct ubifs_info *c)
+{
+ int err, lnum;
+
+ if (c->ro_media)
+ return -EINVAL;
+
+ mutex_lock(&c->umount_mutex);
+ c->remounting_rw = 1;
+
+ /* Check for enough free space */
+ if (ubifs_calc_available(c, c->min_idx_lebs) <= 0) {
+ ubifs_err("insufficient available space");
+ err = -EINVAL;
+ goto out;
+ }
+
+ if (c->old_leb_cnt != c->leb_cnt) {
+ struct ubifs_sb_node *sup;
+
+ sup = ubifs_read_sb_node(c);
+ if (IS_ERR(sup)) {
+ err = PTR_ERR(sup);
+ goto out;
+ }
+ sup->leb_cnt = cpu_to_le32(c->leb_cnt);
+ err = ubifs_write_sb_node(c, sup);
+ if (err)
+ goto out;
+ }
+
+ if (c->need_recovery) {
+ ubifs_msg("completing deferred recovery");
+ err = ubifs_write_rcvrd_mst_node(c);
+ if (err)
+ goto out;
+ err = ubifs_recover_size(c);
+ if (err)
+ goto out;
+ err = ubifs_clean_lebs(c, c->sbuf);
+ if (err)
+ goto out;
+ err = ubifs_recover_inl_heads(c, c->sbuf);
+ if (err)
+ goto out;
+ }
+
+ if (!(c->mst_node->flags & cpu_to_le32(UBIFS_MST_DIRTY))) {
+ c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
+ err = ubifs_write_master(c);
+ if (err)
+ goto out;
+ }
+
+ c->ileb_buf = vmalloc(c->leb_size);
+ if (!c->ileb_buf) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ err = ubifs_lpt_init(c, 0, 1);
+ if (err)
+ goto out;
+
+ err = alloc_wbufs(c);
+ if (err)
+ goto out;
+
+ ubifs_create_buds_lists(c);
+
+ /* Create background thread */
+ c->bgt = kthread_create(ubifs_bg_thread, c, c->bgt_name);
+ if (!c->bgt)
+ c->bgt = ERR_PTR(-EINVAL);
+ if (IS_ERR(c->bgt)) {
+ err = PTR_ERR(c->bgt);
+ c->bgt = NULL;
+ ubifs_err("cannot spawn \"%s\", error %d",
+ c->bgt_name, err);
+ return err;
+ }
+ wake_up_process(c->bgt);
+
+ c->orph_buf = vmalloc(c->leb_size);
+ if (!c->orph_buf)
+ return -ENOMEM;
+
+ /* Check for enough log space */
+ lnum = c->lhead_lnum + 1;
+ if (lnum >= UBIFS_LOG_LNUM + c->log_lebs)
+ lnum = UBIFS_LOG_LNUM;
+ if (lnum == c->ltail_lnum) {
+ err = ubifs_consolidate_log(c);
+ if (err)
+ goto out;
+ }
+
+ if (c->need_recovery)
+ err = ubifs_rcvry_gc_commit(c);
+ else
+ err = take_gc_lnum(c);
+ if (err)
+ goto out;
+
+ if (c->need_recovery) {
+ c->need_recovery = 0;
+ ubifs_msg("deferred recovery completed");
+ }
+
+ dbg_gen("re-mounted read-write");
+ c->vfs_sb->s_flags &= ~MS_RDONLY;
+ c->remounting_rw = 0;
+ mutex_unlock(&c->umount_mutex);
+ return 0;
+
+out:
+ vfree(c->orph_buf);
+ c->orph_buf = NULL;
+ if (c->bgt) {
+ kthread_stop(c->bgt);
+ c->bgt = NULL;
+ }
+ free_wbufs(c);
+ vfree(c->ileb_buf);
+ c->ileb_buf = NULL;
+ ubifs_lpt_free(c, 1);
+ c->remounting_rw = 0;
+ mutex_unlock(&c->umount_mutex);
+ return err;
+}
+
+/**
+ * commit_on_unmount - commit the journal when un-mounting.
+ * @c: UBIFS file-system description object
+ *
+ * This function is called during un-mounting and it commits the journal unless
+ * the "fast unmount" mode is enabled. It also avoids committing the journal if
+ * it contains too few data.
+ *
+ * Sometimes recovery requires the journal to be committed at least once, and
+ * this function takes care about this.
+ */
+static void commit_on_unmount(struct ubifs_info *c)
+{
+ if (!c->fast_unmount) {
+ long long bud_bytes;
+
+ spin_lock(&c->buds_lock);
+ bud_bytes = c->bud_bytes;
+ spin_unlock(&c->buds_lock);
+ if (bud_bytes > c->leb_size)
+ ubifs_run_commit(c);
+ }
+}
+
+/**
+ * ubifs_remount_ro - re-mount in read-only mode.
+ * @c: UBIFS file-system description object
+ *
+ * We rely on VFS to have stopped writing. Possibly the background thread could
+ * be running a commit, however kthread_stop will wait in that case.
+ */
+static void ubifs_remount_ro(struct ubifs_info *c)
+{
+ int i, err;
+
+ ubifs_assert(!c->need_recovery);
+ commit_on_unmount(c);
+
+ mutex_lock(&c->umount_mutex);
+ if (c->bgt) {
+ kthread_stop(c->bgt);
+ c->bgt = NULL;
+ }
+
+ for (i = 0; i < c->jhead_cnt; i++) {
+ ubifs_wbuf_sync(&c->jheads[i].wbuf);
+ del_timer_sync(&c->jheads[i].wbuf.timer);
+ }
+
+ if (!c->ro_media) {
+ c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_DIRTY);
+ c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS);
+ c->mst_node->gc_lnum = cpu_to_le32(c->gc_lnum);
+ err = ubifs_write_master(c);
+ if (err)
+ ubifs_ro_mode(c, err);
+ }
+
+ ubifs_destroy_idx_gc(c);
+ free_wbufs(c);
+ vfree(c->orph_buf);
+ c->orph_buf = NULL;
+ vfree(c->ileb_buf);
+ c->ileb_buf = NULL;
+ ubifs_lpt_free(c, 1);
+ mutex_unlock(&c->umount_mutex);
+}
+
+static void ubifs_put_super(struct super_block *sb)
+{
+ int i;
+ struct ubifs_info *c = sb->s_fs_info;
+
+ ubifs_msg("un-mount UBI device %d, volume %d", c->vi.ubi_num,
+ c->vi.vol_id);
+ /*
+ * The following asserts are only valid if there has not been a failure
+ * of the media. For example, there will be dirty inodes if we failed
+ * to write them back because of I/O errors.
+ */
+ ubifs_assert(atomic_long_read(&c->dirty_pg_cnt) == 0);
+ ubifs_assert(c->budg_idx_growth == 0);
+ ubifs_assert(c->budg_data_growth == 0);
+
+ /*
+ * The 'c->umount_lock' prevents races between UBIFS memory shrinker
+ * and file system un-mount. Namely, it prevents the shrinker from
+ * picking this superblock for shrinking - it will be just skipped if
+ * the mutex is locked.
+ */
+ mutex_lock(&c->umount_mutex);
+ if (!(c->vfs_sb->s_flags & MS_RDONLY)) {
+ /*
+ * First of all kill the background thread to make sure it does
+ * not interfere with un-mounting and freeing resources.
+ */
+ if (c->bgt) {
+ kthread_stop(c->bgt);
+ c->bgt = NULL;
+ }
+
+ /* Synchronize write-buffers */
+ if (c->jheads)
+ for (i = 0; i < c->jhead_cnt; i++) {
+ ubifs_wbuf_sync(&c->jheads[i].wbuf);
+ del_timer_sync(&c->jheads[i].wbuf.timer);
+ }
+
+ /*
+ * On fatal errors c->ro_media is set to 1, in which case we do
+ * not write the master node.
+ */
+ if (!c->ro_media) {
+ /*
+ * We are being cleanly unmounted which means the
+ * orphans were killed - indicate this in the master
+ * node. Also save the reserved GC LEB number.
+ */
+ int err;
+
+ c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_DIRTY);
+ c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS);
+ c->mst_node->gc_lnum = cpu_to_le32(c->gc_lnum);
+ err = ubifs_write_master(c);
+ if (err)
+ /*
+ * Recovery will attempt to fix the master area
+ * next mount, so we just print a message and
+ * continue to unmount normally.
+ */
+ ubifs_err("failed to write master node, "
+ "error %d", err);
+ }
+ }
+
+ ubifs_umount(c);
+ bdi_destroy(&c->bdi);
+ ubi_close_volume(c->ubi);
+ mutex_unlock(&c->umount_mutex);
+ kfree(c);
+}
+
+static int ubifs_remount_fs(struct super_block *sb, int *flags, char *data)
+{
+ int err;
+ struct ubifs_info *c = sb->s_fs_info;
+
+ dbg_gen("old flags %#lx, new flags %#x", sb->s_flags, *flags);
+
+ err = ubifs_parse_options(c, data, 1);
+ if (err) {
+ ubifs_err("invalid or unknown remount parameter");
+ return err;
+ }
+ if ((sb->s_flags & MS_RDONLY) && !(*flags & MS_RDONLY)) {
+ err = ubifs_remount_rw(c);
+ if (err)
+ return err;
+ } else if (!(sb->s_flags & MS_RDONLY) && (*flags & MS_RDONLY))
+ ubifs_remount_ro(c);
+
+ return 0;
+}
+
+struct super_operations ubifs_super_operations = {
+ .alloc_inode = ubifs_alloc_inode,
+ .destroy_inode = ubifs_destroy_inode,
+ .put_super = ubifs_put_super,
+ .write_inode = ubifs_write_inode,
+ .delete_inode = ubifs_delete_inode,
+ .statfs = ubifs_statfs,
+ .dirty_inode = ubifs_dirty_inode,
+ .remount_fs = ubifs_remount_fs,
+ .show_options = ubifs_show_options,
+ .sync_fs = ubifs_sync_fs,
+};
+
+/**
+ * open_ubi - parse UBI device name string and open the UBI device.
+ * @name: UBI volume name
+ * @mode: UBI volume open mode
+ *
+ * There are several ways to specify UBI volumes when mounting UBIFS:
+ * o ubiX_Y - UBI device number X, volume Y;
+ * o ubiY - UBI device number 0, volume Y;
+ * o ubiX:NAME - mount UBI device X, volume with name NAME;
+ * o ubi:NAME - mount UBI device 0, volume with name NAME.
+ *
+ * Alternative '!' separator may be used instead of ':' (because some shells
+ * like busybox may interpret ':' as an NFS host name separator). This function
+ * returns ubi volume object in case of success and a negative error code in
+ * case of failure.
+ */
+static struct ubi_volume_desc *open_ubi(const char *name, int mode)
+{
+ int dev, vol;
+ char *endptr;
+
+ if (name[0] != 'u' || name[1] != 'b' || name[2] != 'i')
+ return ERR_PTR(-EINVAL);
+
+ /* ubi:NAME method */
+ if ((name[3] == ':' || name[3] == '!') && name[4] != '\0')
+ return ubi_open_volume_nm(0, name + 4, mode);
+
+ if (!isdigit(name[3]))
+ return ERR_PTR(-EINVAL);
+
+ dev = simple_strtoul(name + 3, &endptr, 0);
+
+ /* ubiY method */
+ if (*endptr == '\0')
+ return ubi_open_volume(0, dev, mode);
+
+ /* ubiX_Y method */
+ if (*endptr == '_' && isdigit(endptr[1])) {
+ vol = simple_strtoul(endptr + 1, &endptr, 0);
+ if (*endptr != '\0')
+ return ERR_PTR(-EINVAL);
+ return ubi_open_volume(dev, vol, mode);
+ }
+
+ /* ubiX:NAME method */
+ if ((*endptr == ':' || *endptr == '!') && endptr[1] != '\0')
+ return ubi_open_volume_nm(dev, ++endptr, mode);
+
+ return ERR_PTR(-EINVAL);
+}
+
+static int ubifs_fill_super(struct super_block *sb, void *data, int silent)
+{
+ struct ubi_volume_desc *ubi = sb->s_fs_info;
+ struct ubifs_info *c;
+ struct inode *root;
+ int err;
+
+ c = kzalloc(sizeof(struct ubifs_info), GFP_KERNEL);
+ if (!c)
+ return -ENOMEM;
+
+ spin_lock_init(&c->cnt_lock);
+ spin_lock_init(&c->cs_lock);
+ spin_lock_init(&c->buds_lock);
+ spin_lock_init(&c->space_lock);
+ spin_lock_init(&c->orphan_lock);
+ init_rwsem(&c->commit_sem);
+ mutex_init(&c->lp_mutex);
+ mutex_init(&c->tnc_mutex);
+ mutex_init(&c->log_mutex);
+ mutex_init(&c->mst_mutex);
+ mutex_init(&c->umount_mutex);
+ init_waitqueue_head(&c->cmt_wq);
+ c->buds = RB_ROOT;
+ c->old_idx = RB_ROOT;
+ c->size_tree = RB_ROOT;
+ c->orph_tree = RB_ROOT;
+ INIT_LIST_HEAD(&c->infos_list);
+ INIT_LIST_HEAD(&c->idx_gc);
+ INIT_LIST_HEAD(&c->replay_list);
+ INIT_LIST_HEAD(&c->replay_buds);
+ INIT_LIST_HEAD(&c->uncat_list);
+ INIT_LIST_HEAD(&c->empty_list);
+ INIT_LIST_HEAD(&c->freeable_list);
+ INIT_LIST_HEAD(&c->frdi_idx_list);
+ INIT_LIST_HEAD(&c->unclean_leb_list);
+ INIT_LIST_HEAD(&c->old_buds);
+ INIT_LIST_HEAD(&c->orph_list);
+ INIT_LIST_HEAD(&c->orph_new);
+
+ c->highest_inum = UBIFS_FIRST_INO;
+ get_random_bytes(&c->vfs_gen, sizeof(int));
+ c->lhead_lnum = c->ltail_lnum = UBIFS_LOG_LNUM;
+
+ ubi_get_volume_info(ubi, &c->vi);
+ ubi_get_device_info(c->vi.ubi_num, &c->di);
+
+ /* Re-open the UBI device in read-write mode */
+ c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READWRITE);
+ if (IS_ERR(c->ubi)) {
+ err = PTR_ERR(c->ubi);
+ goto out_free;
+ }
+
+ /*
+ * UBIFS provids 'backing_dev_info' in order to disable readahead. For
+ * UBIFS, I/O is not deferred, it is done immediately in readpage,
+ * which means the user would have to wait not just for their own I/O
+ * but the readahead I/O as well i.e. completely pointless.
+ *
+ * Read-ahead will be disabled because @c->bdi.ra_pages is 0.
+ */
+ c->bdi.capabilities = BDI_CAP_MAP_COPY;
+ c->bdi.unplug_io_fn = default_unplug_io_fn;
+ err = bdi_init(&c->bdi);
+ if (err)
+ goto out_close;
+
+ err = ubifs_parse_options(c, data, 0);
+ if (err)
+ goto out_bdi;
+
+ c->vfs_sb = sb;
+
+ sb->s_fs_info = c;
+ sb->s_magic = UBIFS_SUPER_MAGIC;
+ sb->s_blocksize = UBIFS_BLOCK_SIZE;
+ sb->s_blocksize_bits = UBIFS_BLOCK_SHIFT;
+ sb->s_dev = c->vi.cdev;
+ sb->s_maxbytes = c->max_inode_sz = key_max_inode_size(c);
+ if (c->max_inode_sz > MAX_LFS_FILESIZE)
+ sb->s_maxbytes = c->max_inode_sz = MAX_LFS_FILESIZE;
+ sb->s_op = &ubifs_super_operations;
+
+ mutex_lock(&c->umount_mutex);
+ err = mount_ubifs(c);
+ if (err) {
+ ubifs_assert(err < 0);
+ goto out_unlock;
+ }
+
+ /* Read the root inode */
+ root = ubifs_iget(sb, UBIFS_ROOT_INO);
+ if (IS_ERR(root)) {
+ err = PTR_ERR(root);
+ goto out_umount;
+ }
+
+ sb->s_root = d_alloc_root(root);
+ if (!sb->s_root)
+ goto out_iput;
+
+ mutex_unlock(&c->umount_mutex);
+
+ return 0;
+
+out_iput:
+ iput(root);
+out_umount:
+ ubifs_umount(c);
+out_unlock:
+ mutex_unlock(&c->umount_mutex);
+out_bdi:
+ bdi_destroy(&c->bdi);
+out_close:
+ ubi_close_volume(c->ubi);
+out_free:
+ kfree(c);
+ return err;
+}
+
+static int sb_test(struct super_block *sb, void *data)
+{
+ dev_t *dev = data;
+
+ return sb->s_dev == *dev;
+}
+
+static int sb_set(struct super_block *sb, void *data)
+{
+ dev_t *dev = data;
+
+ sb->s_dev = *dev;
+ return 0;
+}
+
+static int ubifs_get_sb(struct file_system_type *fs_type, int flags,
+ const char *name, void *data, struct vfsmount *mnt)
+{
+ struct ubi_volume_desc *ubi;
+ struct ubi_volume_info vi;
+ struct super_block *sb;
+ int err;
+
+ dbg_gen("name %s, flags %#x", name, flags);
+
+ /*
+ * Get UBI device number and volume ID. Mount it read-only so far
+ * because this might be a new mount point, and UBI allows only one
+ * read-write user at a time.
+ */
+ ubi = open_ubi(name, UBI_READONLY);
+ if (IS_ERR(ubi)) {
+ ubifs_err("cannot open \"%s\", error %d",
+ name, (int)PTR_ERR(ubi));
+ return PTR_ERR(ubi);
+ }
+ ubi_get_volume_info(ubi, &vi);
+
+ dbg_gen("opened ubi%d_%d", vi.ubi_num, vi.vol_id);
+
+ sb = sget(fs_type, &sb_test, &sb_set, &vi.cdev);
+ if (IS_ERR(sb)) {
+ err = PTR_ERR(sb);
+ goto out_close;
+ }
+
+ if (sb->s_root) {
+ /* A new mount point for already mounted UBIFS */
+ dbg_gen("this ubi volume is already mounted");
+ if ((flags ^ sb->s_flags) & MS_RDONLY) {
+ err = -EBUSY;
+ goto out_deact;
+ }
+ } else {
+ sb->s_flags = flags;
+ /*
+ * Pass 'ubi' to 'fill_super()' in sb->s_fs_info where it is
+ * replaced by 'c'.
+ */
+ sb->s_fs_info = ubi;
+ err = ubifs_fill_super(sb, data, flags & MS_SILENT ? 1 : 0);
+ if (err)
+ goto out_deact;
+ /* We do not support atime */
+ sb->s_flags |= MS_ACTIVE | MS_NOATIME;
+ }
+
+ /* 'fill_super()' opens ubi again so we must close it here */
+ ubi_close_volume(ubi);
+
+ return simple_set_mnt(mnt, sb);
+
+out_deact:
+ up_write(&sb->s_umount);
+ deactivate_super(sb);
+out_close:
+ ubi_close_volume(ubi);
+ return err;
+}
+
+static void ubifs_kill_sb(struct super_block *sb)
+{
+ struct ubifs_info *c = sb->s_fs_info;
+
+ /*
+ * We do 'commit_on_unmount()' here instead of 'ubifs_put_super()'
+ * in order to be outside BKL.
+ */
+ if (sb->s_root && !(sb->s_flags & MS_RDONLY))
+ commit_on_unmount(c);
+ /* The un-mount routine is actually done in put_super() */
+ generic_shutdown_super(sb);
+}
+
+static struct file_system_type ubifs_fs_type = {
+ .name = "ubifs",
+ .owner = THIS_MODULE,
+ .get_sb = ubifs_get_sb,
+ .kill_sb = ubifs_kill_sb
+};
+
+/*
+ * Inode slab cache constructor.
+ */
+static void inode_slab_ctor(struct kmem_cache *cachep, void *obj)
+{
+ struct ubifs_inode *ui = obj;
+ inode_init_once(&ui->vfs_inode);
+}
+
+static int __init ubifs_init(void)
+{
+ int err;
+
+ BUILD_BUG_ON(sizeof(struct ubifs_ch) != 24);
+
+ /* Make sure node sizes are 8-byte aligned */
+ BUILD_BUG_ON(UBIFS_CH_SZ & 7);
+ BUILD_BUG_ON(UBIFS_INO_NODE_SZ & 7);
+ BUILD_BUG_ON(UBIFS_DENT_NODE_SZ & 7);
+ BUILD_BUG_ON(UBIFS_XENT_NODE_SZ & 7);
+ BUILD_BUG_ON(UBIFS_DATA_NODE_SZ & 7);
+ BUILD_BUG_ON(UBIFS_TRUN_NODE_SZ & 7);
+ BUILD_BUG_ON(UBIFS_SB_NODE_SZ & 7);
+ BUILD_BUG_ON(UBIFS_MST_NODE_SZ & 7);
+ BUILD_BUG_ON(UBIFS_REF_NODE_SZ & 7);
+ BUILD_BUG_ON(UBIFS_CS_NODE_SZ & 7);
+ BUILD_BUG_ON(UBIFS_ORPH_NODE_SZ & 7);
+
+ BUILD_BUG_ON(UBIFS_MAX_DENT_NODE_SZ & 7);
+ BUILD_BUG_ON(UBIFS_MAX_XENT_NODE_SZ & 7);
+ BUILD_BUG_ON(UBIFS_MAX_DATA_NODE_SZ & 7);
+ BUILD_BUG_ON(UBIFS_MAX_INO_NODE_SZ & 7);
+ BUILD_BUG_ON(UBIFS_MAX_NODE_SZ & 7);
+ BUILD_BUG_ON(MIN_WRITE_SZ & 7);
+
+ /* Check min. node size */
+ BUILD_BUG_ON(UBIFS_INO_NODE_SZ < MIN_WRITE_SZ);
+ BUILD_BUG_ON(UBIFS_DENT_NODE_SZ < MIN_WRITE_SZ);
+ BUILD_BUG_ON(UBIFS_XENT_NODE_SZ < MIN_WRITE_SZ);
+ BUILD_BUG_ON(UBIFS_TRUN_NODE_SZ < MIN_WRITE_SZ);
+
+ BUILD_BUG_ON(UBIFS_MAX_DENT_NODE_SZ > UBIFS_MAX_NODE_SZ);
+ BUILD_BUG_ON(UBIFS_MAX_XENT_NODE_SZ > UBIFS_MAX_NODE_SZ);
+ BUILD_BUG_ON(UBIFS_MAX_DATA_NODE_SZ > UBIFS_MAX_NODE_SZ);
+ BUILD_BUG_ON(UBIFS_MAX_INO_NODE_SZ > UBIFS_MAX_NODE_SZ);
+
+ /* Defined node sizes */
+ BUILD_BUG_ON(UBIFS_SB_NODE_SZ != 4096);
+ BUILD_BUG_ON(UBIFS_MST_NODE_SZ != 512);
+ BUILD_BUG_ON(UBIFS_INO_NODE_SZ != 160);
+ BUILD_BUG_ON(UBIFS_REF_NODE_SZ != 64);
+
+ /*
+ * We require that PAGE_CACHE_SIZE is greater-than-or-equal-to
+ * UBIFS_BLOCK_SIZE. It is assumed that both are powers of 2.
+ */
+ if (PAGE_CACHE_SIZE < UBIFS_BLOCK_SIZE) {
+ ubifs_err("VFS page cache size is %u bytes, but UBIFS requires"
+ " at least 4096 bytes",
+ (unsigned int)PAGE_CACHE_SIZE);
+ return -EINVAL;
+ }
+
+ err = register_filesystem(&ubifs_fs_type);
+ if (err) {
+ ubifs_err("cannot register file system, error %d", err);
+ return err;
+ }
+
+ err = -ENOMEM;
+ ubifs_inode_slab = kmem_cache_create("ubifs_inode_slab",
+ sizeof(struct ubifs_inode), 0,
+ SLAB_MEM_SPREAD | SLAB_RECLAIM_ACCOUNT,
+ &inode_slab_ctor);
+ if (!ubifs_inode_slab)
+ goto out_reg;
+
+ register_shrinker(&ubifs_shrinker_info);
+
+ err = ubifs_compressors_init();
+ if (err)
+ goto out_compr;
+
+ return 0;
+
+out_compr:
+ unregister_shrinker(&ubifs_shrinker_info);
+ kmem_cache_destroy(ubifs_inode_slab);
+out_reg:
+ unregister_filesystem(&ubifs_fs_type);
+ return err;
+}
+/* late_initcall to let compressors initialize first */
+late_initcall(ubifs_init);
+
+static void __exit ubifs_exit(void)
+{
+ ubifs_assert(list_empty(&ubifs_infos));
+ ubifs_assert(atomic_long_read(&ubifs_clean_zn_cnt) == 0);
+
+ ubifs_compressors_exit();
+ unregister_shrinker(&ubifs_shrinker_info);
+ kmem_cache_destroy(ubifs_inode_slab);
+ unregister_filesystem(&ubifs_fs_type);
+}
+module_exit(ubifs_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_VERSION(__stringify(UBIFS_VERSION));
+MODULE_AUTHOR("Artem Bityutskiy, Adrian Hunter");
+MODULE_DESCRIPTION("UBIFS - UBI File System");
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ * Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file implements TNC (Tree Node Cache) which caches indexing nodes of
+ * the UBIFS B-tree.
+ *
+ * At the moment the locking rules of the TNC tree are quite simple and
+ * straightforward. We just have a mutex and lock it when we traverse the
+ * tree. If a znode is not in memory, we read it from flash while still having
+ * the mutex locked.
+ */
+
+#include <linux/crc32.h>
+#include "ubifs.h"
+
+/*
+ * Returned codes of 'matches_name()' and 'fallible_matches_name()' functions.
+ * @NAME_LESS: name corresponding to the first argument is less than second
+ * @NAME_MATCHES: names match
+ * @NAME_GREATER: name corresponding to the second argument is greater than
+ * first
+ * @NOT_ON_MEDIA: node referred by zbranch does not exist on the media
+ *
+ * These constants were introduce to improve readability.
+ */
+enum {
+ NAME_LESS = 0,
+ NAME_MATCHES = 1,
+ NAME_GREATER = 2,
+ NOT_ON_MEDIA = 3,
+};
+
+/**
+ * insert_old_idx - record an index node obsoleted since the last commit start.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number of obsoleted index node
+ * @offs: offset of obsoleted index node
+ *
+ * Returns %0 on success, and a negative error code on failure.
+ *
+ * For recovery, there must always be a complete intact version of the index on
+ * flash at all times. That is called the "old index". It is the index as at the
+ * time of the last successful commit. Many of the index nodes in the old index
+ * may be dirty, but they must not be erased until the next successful commit
+ * (at which point that index becomes the old index).
+ *
+ * That means that the garbage collection and the in-the-gaps method of
+ * committing must be able to determine if an index node is in the old index.
+ * Most of the old index nodes can be found by looking up the TNC using the
+ * 'lookup_znode()' function. However, some of the old index nodes may have
+ * been deleted from the current index or may have been changed so much that
+ * they cannot be easily found. In those cases, an entry is added to an RB-tree.
+ * That is what this function does. The RB-tree is ordered by LEB number and
+ * offset because they uniquely identify the old index node.
+ */
+static int insert_old_idx(struct ubifs_info *c, int lnum, int offs)
+{
+ struct ubifs_old_idx *old_idx, *o;
+ struct rb_node **p, *parent = NULL;
+
+ old_idx = kmalloc(sizeof(struct ubifs_old_idx), GFP_NOFS);
+ if (unlikely(!old_idx))
+ return -ENOMEM;
+ old_idx->lnum = lnum;
+ old_idx->offs = offs;
+
+ p = &c->old_idx.rb_node;
+ while (*p) {
+ parent = *p;
+ o = rb_entry(parent, struct ubifs_old_idx, rb);
+ if (lnum < o->lnum)
+ p = &(*p)->rb_left;
+ else if (lnum > o->lnum)
+ p = &(*p)->rb_right;
+ else if (offs < o->offs)
+ p = &(*p)->rb_left;
+ else if (offs > o->offs)
+ p = &(*p)->rb_right;
+ else {
+ ubifs_err("old idx added twice!");
+ kfree(old_idx);
+ return 0;
+ }
+ }
+ rb_link_node(&old_idx->rb, parent, p);
+ rb_insert_color(&old_idx->rb, &c->old_idx);
+ return 0;
+}
+
+/**
+ * insert_old_idx_znode - record a znode obsoleted since last commit start.
+ * @c: UBIFS file-system description object
+ * @znode: znode of obsoleted index node
+ *
+ * Returns %0 on success, and a negative error code on failure.
+ */
+int insert_old_idx_znode(struct ubifs_info *c, struct ubifs_znode *znode)
+{
+ if (znode->parent) {
+ struct ubifs_zbranch *zbr;
+
+ zbr = &znode->parent->zbranch[znode->iip];
+ if (zbr->len)
+ return insert_old_idx(c, zbr->lnum, zbr->offs);
+ } else
+ if (c->zroot.len)
+ return insert_old_idx(c, c->zroot.lnum,
+ c->zroot.offs);
+ return 0;
+}
+
+/**
+ * ins_clr_old_idx_znode - record a znode obsoleted since last commit start.
+ * @c: UBIFS file-system description object
+ * @znode: znode of obsoleted index node
+ *
+ * Returns %0 on success, and a negative error code on failure.
+ */
+static int ins_clr_old_idx_znode(struct ubifs_info *c,
+ struct ubifs_znode *znode)
+{
+ int err;
+
+ if (znode->parent) {
+ struct ubifs_zbranch *zbr;
+
+ zbr = &znode->parent->zbranch[znode->iip];
+ if (zbr->len) {
+ err = insert_old_idx(c, zbr->lnum, zbr->offs);
+ if (err)
+ return err;
+ zbr->lnum = 0;
+ zbr->offs = 0;
+ zbr->len = 0;
+ }
+ } else
+ if (c->zroot.len) {
+ err = insert_old_idx(c, c->zroot.lnum, c->zroot.offs);
+ if (err)
+ return err;
+ c->zroot.lnum = 0;
+ c->zroot.offs = 0;
+ c->zroot.len = 0;
+ }
+ return 0;
+}
+
+/**
+ * destroy_old_idx - destroy the old_idx RB-tree.
+ * @c: UBIFS file-system description object
+ *
+ * During start commit, the old_idx RB-tree is used to avoid overwriting index
+ * nodes that were in the index last commit but have since been deleted. This
+ * is necessary for recovery i.e. the old index must be kept intact until the
+ * new index is successfully written. The old-idx RB-tree is used for the
+ * in-the-gaps method of writing index nodes and is destroyed every commit.
+ */
+void destroy_old_idx(struct ubifs_info *c)
+{
+ struct rb_node *this = c->old_idx.rb_node;
+ struct ubifs_old_idx *old_idx;
+
+ while (this) {
+ if (this->rb_left) {
+ this = this->rb_left;
+ continue;
+ } else if (this->rb_right) {
+ this = this->rb_right;
+ continue;
+ }
+ old_idx = rb_entry(this, struct ubifs_old_idx, rb);
+ this = rb_parent(this);
+ if (this) {
+ if (this->rb_left == &old_idx->rb)
+ this->rb_left = NULL;
+ else
+ this->rb_right = NULL;
+ }
+ kfree(old_idx);
+ }
+ c->old_idx = RB_ROOT;
+}
+
+/**
+ * copy_znode - copy a dirty znode.
+ * @c: UBIFS file-system description object
+ * @znode: znode to copy
+ *
+ * A dirty znode being committed may not be changed, so it is copied.
+ */
+static struct ubifs_znode *copy_znode(struct ubifs_info *c,
+ struct ubifs_znode *znode)
+{
+ struct ubifs_znode *zn;
+
+ zn = kmalloc(c->max_znode_sz, GFP_NOFS);
+ if (unlikely(!zn))
+ return ERR_PTR(-ENOMEM);
+
+ memcpy(zn, znode, c->max_znode_sz);
+ zn->cnext = NULL;
+ __set_bit(DIRTY_ZNODE, &zn->flags);
+ __clear_bit(COW_ZNODE, &zn->flags);
+
+ ubifs_assert(!test_bit(OBSOLETE_ZNODE, &znode->flags));
+ __set_bit(OBSOLETE_ZNODE, &znode->flags);
+
+ if (znode->level != 0) {
+ int i;
+ const int n = zn->child_cnt;
+
+ /* The children now have new parent */
+ for (i = 0; i < n; i++) {
+ struct ubifs_zbranch *zbr = &zn->zbranch[i];
+
+ if (zbr->znode)
+ zbr->znode->parent = zn;
+ }
+ }
+
+ atomic_long_inc(&c->dirty_zn_cnt);
+ return zn;
+}
+
+/**
+ * add_idx_dirt - add dirt due to a dirty znode.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number of index node
+ * @dirt: size of index node
+ *
+ * This function updates lprops dirty space and the new size of the index.
+ */
+static int add_idx_dirt(struct ubifs_info *c, int lnum, int dirt)
+{
+ c->calc_idx_sz -= ALIGN(dirt, 8);
+ return ubifs_add_dirt(c, lnum, dirt);
+}
+
+/**
+ * dirty_cow_znode - ensure a znode is not being committed.
+ * @c: UBIFS file-system description object
+ * @zbr: branch of znode to check
+ *
+ * Returns dirtied znode on success or negative error code on failure.
+ */
+static struct ubifs_znode *dirty_cow_znode(struct ubifs_info *c,
+ struct ubifs_zbranch *zbr)
+{
+ struct ubifs_znode *znode = zbr->znode;
+ struct ubifs_znode *zn;
+ int err;
+
+ if (!test_bit(COW_ZNODE, &znode->flags)) {
+ /* znode is not being committed */
+ if (!test_and_set_bit(DIRTY_ZNODE, &znode->flags)) {
+ atomic_long_inc(&c->dirty_zn_cnt);
+ atomic_long_dec(&c->clean_zn_cnt);
+ atomic_long_dec(&ubifs_clean_zn_cnt);
+ err = add_idx_dirt(c, zbr->lnum, zbr->len);
+ if (unlikely(err))
+ return ERR_PTR(err);
+ }
+ return znode;
+ }
+
+ zn = copy_znode(c, znode);
+ if (unlikely(IS_ERR(zn)))
+ return zn;
+
+ if (zbr->len) {
+ err = insert_old_idx(c, zbr->lnum, zbr->offs);
+ if (unlikely(err))
+ return ERR_PTR(err);
+ err = add_idx_dirt(c, zbr->lnum, zbr->len);
+ } else
+ err = 0;
+
+ zbr->znode = zn;
+ zbr->lnum = 0;
+ zbr->offs = 0;
+ zbr->len = 0;
+
+ if (unlikely(err))
+ return ERR_PTR(err);
+ return zn;
+}
+
+/**
+ * lnc_add - add a leaf node to the leaf node cache.
+ * @c: UBIFS file-system description object
+ * @zbr: zbranch of leaf node
+ * @node: leaf node
+ *
+ * Leaf nodes are non-index nodes directory entry nodes or data nodes. The
+ * purpose of the leaf node cache is to save re-reading the same leaf node over
+ * and over again. Most things are cached by VFS, however the file system must
+ * cache directory entries for readdir and for resolving hash collisions. The
+ * present implementation of the leaf node cache is extremely simple, and
+ * allows for error returns that are not used but that may be needed if a more
+ * complex implementation is created.
+ *
+ * Note, this function does not add the @node object to LNC directly, but
+ * allocates a copy of the object and adds the copy to LNC. The reason for this
+ * is that @node has been allocated outside of the TNC subsystem and will be
+ * used with @c->tnc_mutex unlock upon return from the TNC subsystem. But LNC
+ * may be changed at any time, e.g. freed by the shrinker.
+ */
+static int lnc_add(struct ubifs_info *c, struct ubifs_zbranch *zbr,
+ const void *node)
+{
+ int err;
+ void *lnc_node;
+ const struct ubifs_dent_node *dent = node;
+
+ ubifs_assert(!zbr->leaf);
+ ubifs_assert(zbr->len != 0);
+ ubifs_assert(is_hash_key(c, &zbr->key));
+
+ err = ubifs_validate_entry(c, dent);
+ if (err) {
+ dbg_dump_stack();
+ dbg_dump_node(c, dent);
+ return err;
+ }
+
+ lnc_node = kmalloc(zbr->len, GFP_NOFS);
+ if (!lnc_node)
+ /* We don't have to have the cache, so no error */
+ return 0;
+
+ memcpy(lnc_node, node, zbr->len);
+ zbr->leaf = lnc_node;
+ return 0;
+}
+
+ /**
+ * lnc_add_directly - add a leaf node to the leaf-node-cache.
+ * @c: UBIFS file-system description object
+ * @zbr: zbranch of leaf node
+ * @node: leaf node
+ *
+ * This function is similar to 'lnc_add()', but it does not create a copy of
+ * @node but inserts @node to TNC directly.
+ */
+static int lnc_add_directly(struct ubifs_info *c, struct ubifs_zbranch *zbr,
+ void *node)
+{
+ int err;
+
+ ubifs_assert(!zbr->leaf);
+ ubifs_assert(zbr->len != 0);
+
+ err = ubifs_validate_entry(c, node);
+ if (err) {
+ dbg_dump_stack();
+ dbg_dump_node(c, node);
+ return err;
+ }
+
+ zbr->leaf = node;
+ return 0;
+}
+
+/**
+ * lnc_free - remove a leaf node from the leaf node cache.
+ * @zbr: zbranch of leaf node
+ * @node: leaf node
+ */
+static void lnc_free(struct ubifs_zbranch *zbr)
+{
+ if (!zbr->leaf)
+ return;
+ kfree(zbr->leaf);
+ zbr->leaf = NULL;
+}
+
+/**
+ * tnc_read_node_nm - read a "hashed" leaf node.
+ * @c: UBIFS file-system description object
+ * @zbr: key and position of the node
+ * @node: node is returned here
+ *
+ * This function reads a "hashed" node defined by @zbr from the leaf node cache
+ * (in it is there) or from the hash media, in which case the node is also
+ * added to LNC. Returns zero in case of success or a negative negative error
+ * code in case of failure.
+ */
+static int tnc_read_node_nm(struct ubifs_info *c, struct ubifs_zbranch *zbr,
+ void *node)
+{
+ int err;
+
+ ubifs_assert(is_hash_key(c, &zbr->key));
+
+ if (zbr->leaf) {
+ /* Read from the leaf node cache */
+ ubifs_assert(zbr->len != 0);
+ memcpy(node, zbr->leaf, zbr->len);
+ return 0;
+ }
+
+ err = ubifs_tnc_read_node(c, zbr, node);
+ if (err)
+ return err;
+
+ /* Add the node to the leaf node cache */
+ err = lnc_add(c, zbr, node);
+ return err;
+}
+
+/**
+ * try_read_node - read a node if it is a node.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to read to
+ * @type: node type
+ * @len: node length (not aligned)
+ * @lnum: LEB number of node to read
+ * @offs: offset of node to read
+ *
+ * This function tries to read a node of known type and length, checks it and
+ * stores it in @buf. This function returns %1 if a node is present and %0 if
+ * a node is not present. A negative error code is returned for I/O errors.
+ * This function performs that same function as ubifs_read_node except that
+ * it does not require that there is actually a node present and instead
+ * the return code indicates if a node was read.
+ */
+static int try_read_node(const struct ubifs_info *c, void *buf, int type,
+ int len, int lnum, int offs)
+{
+ int err, node_len;
+ struct ubifs_ch *ch = buf;
+ uint32_t crc, node_crc;
+
+ dbg_io("LEB %d:%d, %s, length %d", lnum, offs, dbg_ntype(type), len);
+
+ err = ubi_read(c->ubi, lnum, buf, offs, len);
+ if (err) {
+ ubifs_err("cannot read node type %d from LEB %d:%d, error %d",
+ type, lnum, offs, err);
+ return err;
+ }
+
+ if (le32_to_cpu(ch->magic) != UBIFS_NODE_MAGIC)
+ return 0;
+
+ if (ch->node_type != type)
+ return 0;
+
+ node_len = le32_to_cpu(ch->len);
+ if (node_len != len)
+ return 0;
+
+ crc = crc32(UBIFS_CRC32_INIT, buf + 8, node_len - 8);
+ node_crc = le32_to_cpu(ch->crc);
+ if (crc != node_crc)
+ return 0;
+
+ return 1;
+}
+
+/**
+ * fallible_read_node - try to read a leaf node.
+ * @c: UBIFS file-system description object
+ * @key: key of node to read
+ * @zbr: position of node
+ * @node: node returned
+ *
+ * This function tries to read a node and returns %1 if the node is read, %0
+ * if the node is not present, and a negative error code in the case of error.
+ */
+static int fallible_read_node(struct ubifs_info *c, const union ubifs_key *key,
+ struct ubifs_zbranch *zbr, void *node)
+{
+ int ret;
+
+ dbg_tnc("LEB %d:%d, key %s", zbr->lnum, zbr->offs, DBGKEY(key));
+
+ ret = try_read_node(c, node, key_type(c, key), zbr->len, zbr->lnum,
+ zbr->offs);
+ if (ret == 1) {
+ union ubifs_key node_key;
+ struct ubifs_dent_node *dent = node;
+
+ /* All nodes have key in the same place */
+ key_read(c, &dent->key, &node_key);
+ if (keys_cmp(c, key, &node_key) != 0)
+ ret = 0;
+ }
+ if (ret == 0)
+ dbg_mnt("dangling branch LEB %d:%d len %d, key %s",
+ zbr->lnum, zbr->offs, zbr->len, DBGKEY(key));
+ return ret;
+}
+
+/**
+ * matches_name - determine if a direntry or xattr entry matches a given name.
+ * @c: UBIFS file-system description object
+ * @zbr: zbranch of dent
+ * @nm: name to match
+ *
+ * This function checks if xentry/direntry referred by zbranch @zbr matches name
+ * @nm. Returns %NAME_MATCHES if it does, %NAME_LESS if the name referred by
+ * @zbr is less than @nm, and %NAME_GREATER if it is greater than @nm. In case
+ * of failure, a negative error code is returned.
+ */
+static int matches_name(struct ubifs_info *c, struct ubifs_zbranch *zbr,
+ const struct qstr *nm)
+{
+ struct ubifs_dent_node *dent;
+ int nlen, err;
+
+ /* If possible, match against the dent in the leaf node cache */
+ if (!zbr->leaf) {
+ dent = kmalloc(zbr->len, GFP_NOFS);
+ if (!dent)
+ return -ENOMEM;
+
+ err = ubifs_tnc_read_node(c, zbr, dent);
+ if (err)
+ goto out_free;
+
+ /* Add the node to the leaf node cache */
+ err = lnc_add_directly(c, zbr, dent);
+ if (err)
+ goto out_free;
+ } else
+ dent = zbr->leaf;
+
+ nlen = le16_to_cpu(dent->nlen);
+ err = memcmp(dent->name, nm->name, min_t(int, nlen, nm->len));
+ if (err == 0) {
+ if (nlen == nm->len)
+ return NAME_MATCHES;
+ else if (nlen < nm->len)
+ return NAME_LESS;
+ else
+ return NAME_GREATER;
+ } else if (err < 0)
+ return NAME_LESS;
+ else
+ return NAME_GREATER;
+
+out_free:
+ kfree(dent);
+ return err;
+}
+
+/**
+ * get_znode - get a TNC znode that may not be loaded yet.
+ * @c: UBIFS file-system description object
+ * @znode: parent znode
+ * @n: znode branch slot number
+ *
+ * This function returns the znode or a negative error code.
+ */
+static struct ubifs_znode *get_znode(struct ubifs_info *c,
+ struct ubifs_znode *znode, int n)
+{
+ struct ubifs_zbranch *zbr;
+
+ zbr = &znode->zbranch[n];
+ if (zbr->znode)
+ znode = zbr->znode;
+ else
+ znode = ubifs_load_znode(c, zbr, znode, n);
+ return znode;
+}
+
+/**
+ * tnc_next - find next TNC entry.
+ * @c: UBIFS file-system description object
+ * @zn: znode is passed and returned here
+ * @n: znode branch slot number is passed and returned here
+ *
+ * This function returns %0 if the next TNC entry is found, %-ENOENT if there is
+ * no next entry, or a negative error code otherwise.
+ */
+static int tnc_next(struct ubifs_info *c, struct ubifs_znode **zn, int *n)
+{
+ struct ubifs_znode *znode = *zn;
+ int nn = *n;
+
+ nn += 1;
+ if (nn < znode->child_cnt) {
+ *n = nn;
+ return 0;
+ }
+ while (1) {
+ struct ubifs_znode *zp;
+
+ zp = znode->parent;
+ if (!zp)
+ return -ENOENT;
+ nn = znode->iip + 1;
+ znode = zp;
+ if (nn < znode->child_cnt) {
+ znode = get_znode(c, znode, nn);
+ if (IS_ERR(znode))
+ return PTR_ERR(znode);
+ while (znode->level != 0) {
+ znode = get_znode(c, znode, 0);
+ if (IS_ERR(znode))
+ return PTR_ERR(znode);
+ }
+ nn = 0;
+ break;
+ }
+ }
+ *zn = znode;
+ *n = nn;
+ return 0;
+}
+
+/**
+ * tnc_prev - find previous TNC entry.
+ * @c: UBIFS file-system description object
+ * @zn: znode is returned here
+ * @n: znode branch slot number is passed and returned here
+ *
+ * This function returns %0 if the previous TNC entry is found, %-ENOENT if
+ * there is no next entry, or a negative error code otherwise.
+ */
+static int tnc_prev(struct ubifs_info *c, struct ubifs_znode **zn, int *n)
+{
+ struct ubifs_znode *znode = *zn;
+ int nn = *n;
+
+ if (nn > 0) {
+ *n = nn - 1;
+ return 0;
+ }
+ while (1) {
+ struct ubifs_znode *zp;
+
+ zp = znode->parent;
+ if (!zp)
+ return -ENOENT;
+ nn = znode->iip - 1;
+ znode = zp;
+ if (nn >= 0) {
+ znode = get_znode(c, znode, nn);
+ if (IS_ERR(znode))
+ return PTR_ERR(znode);
+ while (znode->level != 0) {
+ nn = znode->child_cnt - 1;
+ znode = get_znode(c, znode, nn);
+ if (IS_ERR(znode))
+ return PTR_ERR(znode);
+ }
+ nn = znode->child_cnt - 1;
+ break;
+ }
+ }
+ *zn = znode;
+ *n = nn;
+ return 0;
+}
+
+/**
+ * resolve_collision - resolve a collision.
+ * @c: UBIFS file-system description object
+ * @key: key of a directory or extended attribute entry
+ * @zn: znode is returned here
+ * @n: zbranch number is passed and returned here
+ * @nm: name of the entry
+ *
+ * This function is called for "hashed" keys to make sure that the found key
+ * really corresponds to the looked up node (directory or extended attribute
+ * entry). It returns %1 and sets @zn and @n if the collision is resolved.
+ * %0 is returned if @nm is not found and @zn and @n are set to the previous
+ * entry, i.e. to the entry after which @nm could follow if it were in TNC.
+ * This means that @n may be set to %-1 if the leftmost key in @zn is the
+ * previous one. A negative error code is returned on failures.
+ */
+static int resolve_collision(struct ubifs_info *c, const union ubifs_key *key,
+ struct ubifs_znode **zn, int *n,
+ const struct qstr *nm)
+{
+ int err;
+
+ err = matches_name(c, &(*zn)->zbranch[*n], nm);
+ if (unlikely(err < 0))
+ return err;
+ if (err == NAME_MATCHES)
+ return 1;
+
+ if (err == NAME_GREATER) {
+ /* Look left */
+ while (1) {
+ err = tnc_prev(c, zn, n);
+ if (err == -ENOENT) {
+ ubifs_assert(*n == 0);
+ *n = -1;
+ return 0;
+ }
+ if (err < 0)
+ return err;
+ if (keys_cmp(c, &(*zn)->zbranch[*n].key, key)) {
+ /*
+ * We have found the branch after which we would
+ * like to insert, but inserting in this znode
+ * may still be wrong. Consider the following 3
+ * znodes, in the case where we are resolving a
+ * collision with Key2.
+ *
+ * znode zp
+ * ----------------------
+ * level 1 | Key0 | Key1 |
+ * -----------------------
+ * | |
+ * znode za | | znode zb
+ * ------------ ------------
+ * level 0 | Key0 | | Key2 |
+ * ------------ ------------
+ *
+ * The lookup finds Key2 in znode zb. Lets say
+ * there is no match and the name is greater so
+ * we look left. When we find Key0, we end up
+ * here. If we return now, we will insert into
+ * znode za at slot n = 1. But that is invalid
+ * according to the parent's keys. Key2 must
+ * be inserted into znode zb.
+ *
+ * Note, this problem is not relevant for the
+ * case when we go right, because
+ * 'tnc_insert()' would correct the parent key.
+ */
+ if (*n == (*zn)->child_cnt - 1) {
+ err = tnc_next(c, zn, n);
+ if (err) {
+ /* Should be impossible */
+ ubifs_assert(0);
+ if (err == -ENOENT)
+ err = -EINVAL;
+ return err;
+ }
+ ubifs_assert(*n == 0);
+ *n = -1;
+ }
+ return 0;
+ }
+ err = matches_name(c, &(*zn)->zbranch[*n], nm);
+ if (err < 0)
+ return err;
+ if (err == NAME_LESS)
+ return 0;
+ if (err == NAME_MATCHES)
+ return 1;
+ ubifs_assert(err == NAME_GREATER);
+ }
+ } else {
+ int nn = *n;
+ struct ubifs_znode *znode = *zn;
+
+ /* Look right */
+ while (1) {
+ err = tnc_next(c, &znode, &nn);
+ if (err == -ENOENT)
+ return 0;
+ if (err < 0)
+ return err;
+ if (keys_cmp(c, &znode->zbranch[nn].key, key))
+ return 0;
+ err = matches_name(c, &znode->zbranch[nn], nm);
+ if (err < 0)
+ return err;
+ if (err == NAME_GREATER)
+ return 0;
+ *zn = znode;
+ *n = nn;
+ if (err == NAME_MATCHES)
+ return 1;
+ ubifs_assert(err == NAME_LESS);
+ }
+ }
+}
+
+/**
+ * fallible_matches_name - determine if a dent matches a given name.
+ * @c: UBIFS file-system description object
+ * @zbr: zbranch of dent
+ * @nm: name to match
+ *
+ * This is a "fallible" version of 'matches_name()' function which does not
+ * panic if the direntry/xentry referred by @zbr does not exist on the media.
+ *
+ * This function checks if xentry/direntry referred by zbranch @zbr matches name
+ * @nm. Returns %NAME_MATCHES it does, %NAME_LESS if the name referred by @zbr
+ * is less than @nm, %NAME_GREATER if it is greater than @nm, and @NOT_ON_MEDIA
+ * if xentry/direntry referred by @zbr does not exist on the media. A negative
+ * error code is returned in case of failure.
+ */
+static int fallible_matches_name(struct ubifs_info *c,
+ struct ubifs_zbranch *zbr,
+ const struct qstr *nm)
+{
+ struct ubifs_dent_node *dent;
+ int nlen, err;
+
+ /* If possible, match against the dent in the leaf node cache */
+ if (!zbr->leaf) {
+ dent = kmalloc(zbr->len, GFP_NOFS);
+ if (!dent)
+ return -ENOMEM;
+
+ err = fallible_read_node(c, &zbr->key, zbr, dent);
+ if (err < 0)
+ goto out_free;
+ if (err == 0) {
+ /* The node was not present */
+ err = NOT_ON_MEDIA;
+ goto out_free;
+ }
+ ubifs_assert(err == 1);
+
+ err = lnc_add_directly(c, zbr, dent);
+ if (err)
+ goto out_free;
+ } else
+ dent = zbr->leaf;
+
+ nlen = le16_to_cpu(dent->nlen);
+ err = memcmp(dent->name, nm->name, min_t(int, nlen, nm->len));
+ if (err == 0) {
+ if (nlen == nm->len)
+ return NAME_MATCHES;
+ else if (nlen < nm->len)
+ return NAME_LESS;
+ else
+ return NAME_GREATER;
+ } else if (err < 0)
+ return NAME_LESS;
+ else
+ return NAME_GREATER;
+
+out_free:
+ kfree(dent);
+ return err;
+}
+
+/**
+ * fallible_resolve_collision - resolve a collision even if nodes are missing.
+ * @c: UBIFS file-system description object
+ * @key: key
+ * @zn: znode is returned here
+ * @n: branch number is passed and returned here
+ * @nm: name of directory entry
+ * @adding: indicates caller is adding a key to the TNC
+ *
+ * This is a "fallible" version of the 'resolve_collision()' function which
+ * does not panic if one of the nodes referred to by TNC does not exist on the
+ * media. This may happen when replaying the journal if a deleted node was
+ * Garbage-collected and the commit was not done. A branch that refers to a node
+ * that is not present is called a dangling branch. The following are the return
+ * codes for this function:
+ * o if @nm was found, %1 is returned and @zn and @n are set to the found
+ * branch;
+ * o if we are @adding and @nm was not found, %0 is returned;
+ * o if we are not @adding and @nm was not found, but a dangling branch was
+ * found, then %1 is returned and @zn and @n are set to the dangling branch;
+ * o a negative error code is returned in case of failure.
+ */
+static int fallible_resolve_collision(struct ubifs_info *c,
+ const union ubifs_key *key,
+ struct ubifs_znode **zn, int *n,
+ const struct qstr *nm, int adding)
+{
+ struct ubifs_znode *o_znode = NULL, *znode = *zn;
+ int uninitialized_var(o_n), err, cmp, unsure = 0, nn = *n;
+
+ cmp = fallible_matches_name(c, &znode->zbranch[nn], nm);
+ if (unlikely(cmp < 0))
+ return cmp;
+ if (cmp == NAME_MATCHES)
+ return 1;
+ if (cmp == NOT_ON_MEDIA) {
+ o_znode = znode;
+ o_n = nn;
+ /*
+ * We are unlucky and hit a dangling branch straight away.
+ * Now we do not really know where to go to find the needed
+ * branch - to the left or to the right. Well, let's try left.
+ */
+ unsure = 1;
+ } else if (!adding)
+ unsure = 1; /* Remove a dangling branch wherever it is */
+
+ if (cmp == NAME_GREATER || unsure) {
+ /* Look left */
+ while (1) {
+ err = tnc_prev(c, zn, n);
+ if (err == -ENOENT) {
+ ubifs_assert(*n == 0);
+ *n = -1;
+ break;
+ }
+ if (err < 0)
+ return err;
+ if (keys_cmp(c, &(*zn)->zbranch[*n].key, key)) {
+ /* See comments in 'resolve_collision()' */
+ if (*n == (*zn)->child_cnt - 1) {
+ err = tnc_next(c, zn, n);
+ if (err) {
+ /* Should be impossible */
+ ubifs_assert(0);
+ if (err == -ENOENT)
+ err = -EINVAL;
+ return err;
+ }
+ ubifs_assert(*n == 0);
+ *n = -1;
+ }
+ break;
+ }
+ err = fallible_matches_name(c, &(*zn)->zbranch[*n], nm);
+ if (err < 0)
+ return err;
+ if (err == NAME_MATCHES)
+ return 1;
+ if (err == NOT_ON_MEDIA) {
+ o_znode = *zn;
+ o_n = *n;
+ continue;
+ }
+ if (!adding)
+ continue;
+ if (err == NAME_LESS)
+ break;
+ else
+ unsure = 0;
+ }
+ }
+
+ if (cmp == NAME_LESS || unsure) {
+ /* Look right */
+ *zn = znode;
+ *n = nn;
+ while (1) {
+ err = tnc_next(c, &znode, &nn);
+ if (err == -ENOENT)
+ break;
+ if (err < 0)
+ return err;
+ if (keys_cmp(c, &znode->zbranch[nn].key, key))
+ break;
+ err = fallible_matches_name(c, &znode->zbranch[nn], nm);
+ if (err < 0)
+ return err;
+ if (err == NAME_GREATER)
+ break;
+ *zn = znode;
+ *n = nn;
+ if (err == NAME_MATCHES)
+ return 1;
+ if (err == NOT_ON_MEDIA) {
+ o_znode = znode;
+ o_n = nn;
+ }
+ }
+ }
+
+ /* Never match a dangling branch when adding */
+ if (adding || !o_znode)
+ return 0;
+
+ dbg_mnt("dangling match LEB %d:%d len %d %s",
+ o_znode->zbranch[o_n].lnum, o_znode->zbranch[o_n].offs,
+ o_znode->zbranch[o_n].len, DBGKEY(key));
+ *zn = o_znode;
+ *n = o_n;
+ return 1;
+}
+
+/**
+ * matches_position - determine if a zbranch matches a given position.
+ * @zbr: zbranch of dent
+ * @lnum: LEB number of dent to match
+ * @offs: offset of dent to match
+ *
+ * This function returns %1 if @lnum:@offs matches, and %0 otherwise.
+ */
+static int matches_position(struct ubifs_zbranch *zbr, int lnum, int offs)
+{
+ if (zbr->lnum == lnum && zbr->offs == offs)
+ return 1;
+ else
+ return 0;
+}
+
+/**
+ * resolve_collision_directly - resolve a collision directly.
+ * @c: UBIFS file-system description object
+ * @key: key of directory entry
+ * @zn: znode is passed and returned here
+ * @n: zbranch number is passed and returned here
+ * @lnum: LEB number of dent node to match
+ * @offs: offset of dent node to match
+ *
+ * This function is used for "hashed" keys to make sure the found directory or
+ * extended attribute entry node is what was looked for. It is used when the
+ * flash address of the right node is known (@lnum:@offs) which makes it much
+ * easier to resolve collisions (no need to read entries and match full
+ * names). This function returns %1 and sets @zn and @n if the collision is
+ * resolved, %0 if @lnum:@offs is not found and @zn and @n are set to the
+ * previous directory entry. Otherwise a negative error code is returned.
+ */
+static int resolve_collision_directly(struct ubifs_info *c,
+ const union ubifs_key *key,
+ struct ubifs_znode **zn, int *n,
+ int lnum, int offs)
+{
+ struct ubifs_znode *znode;
+ int nn, err;
+
+ znode = *zn;
+ nn = *n;
+ if (matches_position(&znode->zbranch[nn], lnum, offs))
+ return 1;
+
+ /* Look left */
+ while (1) {
+ err = tnc_prev(c, &znode, &nn);
+ if (err == -ENOENT)
+ break;
+ if (err < 0)
+ return err;
+ if (keys_cmp(c, &znode->zbranch[nn].key, key))
+ break;
+ if (matches_position(&znode->zbranch[nn], lnum, offs)) {
+ *zn = znode;
+ *n = nn;
+ return 1;
+ }
+ }
+
+ /* Look right */
+ znode = *zn;
+ nn = *n;
+ while (1) {
+ err = tnc_next(c, &znode, &nn);
+ if (err == -ENOENT)
+ return 0;
+ if (err < 0)
+ return err;
+ if (keys_cmp(c, &znode->zbranch[nn].key, key))
+ return 0;
+ *zn = znode;
+ *n = nn;
+ if (matches_position(&znode->zbranch[nn], lnum, offs))
+ return 1;
+ }
+}
+
+/**
+ * dirty_cow_bottom_up - dirty a znode and its ancestors.
+ * @c: UBIFS file-system description object
+ * @znode: znode to dirty
+ *
+ * If we do not have a unique key that resides in a znode, then we cannot
+ * dirty that znode from the top down (i.e. by using lookup_level0_dirty)
+ * This function records the path back to the last dirty ancestor, and then
+ * dirties the znodes on that path.
+ */
+static struct ubifs_znode *dirty_cow_bottom_up(struct ubifs_info *c,
+ struct ubifs_znode *znode)
+{
+ struct ubifs_znode *zp;
+ int *path = c->bottom_up_buf, p = 0;
+
+ ubifs_assert(c->zroot.znode);
+ ubifs_assert(znode);
+ if (c->zroot.znode->level > BOTTOM_UP_HEIGHT) {
+ kfree(c->bottom_up_buf);
+ c->bottom_up_buf = kmalloc(c->zroot.znode->level * sizeof(int),
+ GFP_NOFS);
+ if (!c->bottom_up_buf)
+ return ERR_PTR(-ENOMEM);
+ path = c->bottom_up_buf;
+ }
+ if (c->zroot.znode->level) {
+ /* Go up until parent is dirty */
+ while (1) {
+ int n;
+
+ zp = znode->parent;
+ if (!zp)
+ break;
+ n = znode->iip;
+ ubifs_assert(p < c->zroot.znode->level);
+ path[p++] = n;
+ if (!zp->cnext && ubifs_zn_dirty(znode))
+ break;
+ znode = zp;
+ }
+ }
+
+ /* Come back down, dirtying as we go */
+ while (1) {
+ struct ubifs_zbranch *zbr;
+
+ zp = znode->parent;
+ if (zp) {
+ ubifs_assert(path[p - 1] >= 0);
+ ubifs_assert(path[p - 1] < zp->child_cnt);
+ zbr = &zp->zbranch[path[--p]];
+ znode = dirty_cow_znode(c, zbr);
+ } else {
+ ubifs_assert(znode == c->zroot.znode);
+ znode = dirty_cow_znode(c, &c->zroot);
+ }
+ if (unlikely(IS_ERR(znode)) || !p)
+ break;
+ ubifs_assert(path[p - 1] >= 0);
+ ubifs_assert(path[p - 1] < znode->child_cnt);
+ znode = znode->zbranch[path[p - 1]].znode;
+ }
+
+ return znode;
+}
+
+/**
+ * ubifs_lookup_level0 - search for zero-level znode.
+ * @c: UBIFS file-system description object
+ * @key: key to lookup
+ * @zn: znode is returned here
+ * @n: znode branch slot number is returned here
+ *
+ * This function looks up the TNC tree and search for zero-level znode which
+ * refers key @key. The found zero-level znode is returned in @zn. There are 3
+ * cases:
+ * o exact match, i.e. the found zero-level znode contains key @key, then %1
+ * is returned and slot number of the matched branch is stored in @n;
+ * o not exact match, which means that zero-level znode does not contain
+ * @key, then %0 is returned and slot number of the closed branch is stored
+ * in @n;
+ * o @key is so small that it is even less than the lowest key of the
+ * leftmost zero-level node, then %0 is returned and %0 is stored in @n.
+ *
+ * Note, when the TNC tree is traversed, some znodes may be absent, then this
+ * function reads corresponding indexing nodes and inserts them to TNC. In
+ * case of failure, a negative error code is returned.
+ */
+int ubifs_lookup_level0(struct ubifs_info *c, const union ubifs_key *key,
+ struct ubifs_znode **zn, int *n)
+{
+ int err, exact;
+ struct ubifs_znode *znode;
+ unsigned long time = get_seconds();
+
+ dbg_tnc("search key %s", DBGKEY(key));
+
+ znode = c->zroot.znode;
+ if (unlikely(!znode)) {
+ znode = ubifs_load_znode(c, &c->zroot, NULL, 0);
+ if (IS_ERR(znode))
+ return PTR_ERR(znode);
+ }
+
+ znode->time = time;
+
+ while (1) {
+ struct ubifs_zbranch *zbr;
+
+ exact = ubifs_search_zbranch(c, znode, key, n);
+
+ if (znode->level == 0)
+ break;
+
+ if (*n < 0)
+ *n = 0;
+ zbr = &znode->zbranch[*n];
+
+ if (zbr->znode) {
+ znode->time = time;
+ znode = zbr->znode;
+ continue;
+ }
+
+ /* znode is not in TNC cache, load it from the media */
+ znode = ubifs_load_znode(c, zbr, znode, *n);
+ if (IS_ERR(znode))
+ return PTR_ERR(znode);
+ }
+
+ *zn = znode;
+ if (exact || !is_hash_key(c, key) || *n != -1) {
+ dbg_tnc("found %d, lvl %d, n %d", exact, znode->level, *n);
+ return exact;
+ }
+
+ /*
+ * Here is a tricky place. We have not found the key and this is a
+ * "hashed" key, which may collide. The rest of the code deals with
+ * situations like this:
+ *
+ * | 3 | 5 |
+ * / \
+ * | 3 | 5 | | 6 | 7 | (x)
+ *
+ * Or more a complex example:
+ *
+ * | 1 | 5 |
+ * / \
+ * | 1 | 3 | | 5 | 8 |
+ * \ /
+ * | 5 | 5 | | 6 | 7 | (x)
+ *
+ * In the examples, if we are looking for key "5", we may reach nodes
+ * marked with "(x)". In this case what we have do is to look at the
+ * left and see if there is "5" key there. If there is, we have to
+ * return it.
+ *
+ * Note, this whole situation is possible because we allow to have
+ * elements which are equivalent to the next key in the parent in the
+ * children of current znode. For example, this happens if we split a
+ * znode like this: | 3 | 5 | 5 | 6 | 7 |, which results in something
+ * like this:
+ * | 3 | 5 |
+ * / \
+ * | 3 | 5 | | 5 | 6 | 7 |
+ * ^
+ * And this becomes what is at the first "picture" after key "5" marked
+ * with "^" is removed. What could be done is we could prohibit
+ * splitting in the middle of the colliding sequence. Also, when
+ * removing the leftmost key, we would have to correct the key of the
+ * parent node, which would introduce additional complications. Namely,
+ * if we changed the the leftmost key of the parent znode, the garbage
+ * collector would be unable to find it (GC is doing this when GC'ing
+ * indexing LEBs). Although we already have an additional RB-tree where
+ * we save such changed znodes (see 'ins_clr_old_idx_znode()') until
+ * after the commit. But anyway, this does not look easy to implement
+ * so we did not try this.
+ */
+ err = tnc_prev(c, &znode, n);
+ if (err == -ENOENT) {
+ dbg_tnc("found 0, lvl %d, n -1", znode->level);
+ *n = -1;
+ return 0;
+ }
+ if (unlikely(err < 0))
+ return err;
+ if (keys_cmp(c, key, &znode->zbranch[*n].key)) {
+ dbg_tnc("found 0, lvl %d, n -1", znode->level);
+ *n = -1;
+ return 0;
+ }
+
+ dbg_tnc("found 1, lvl %d, n %d", znode->level, *n);
+ *zn = znode;
+ return 1;
+}
+
+/**
+ * lookup_level0_dirty - search for zero-level znode dirtying.
+ * @c: UBIFS file-system description object
+ * @key: key to lookup
+ * @zn: znode is returned here
+ * @n: znode branch slot number is returned here
+ *
+ * This function looks up the TNC tree and search for zero-level znode which
+ * refers key @key. The found zero-level znode is returned in @zn. There are 3
+ * cases:
+ * o exact match, i.e. the found zero-level znode contains key @key, then %1
+ * is returned and slot number of the matched branch is stored in @n;
+ * o not exact match, which means that zero-level znode does not contain @key
+ * then %0 is returned and slot number of the closed branch is stored in
+ * @n;
+ * o @key is so small that it is even less than the lowest key of the
+ * leftmost zero-level node, then %0 is returned and %-1 is stored in @n.
+ *
+ * Additionally all znodes in the path from the root to the located zero-level
+ * znode are marked as dirty.
+ *
+ * Note, when the TNC tree is traversed, some znodes may be absent, then this
+ * function reads corresponding indexing nodes and inserts them to TNC. In
+ * case of failure, a negative error code is returned.
+ */
+static int lookup_level0_dirty(struct ubifs_info *c, const union ubifs_key *key,
+ struct ubifs_znode **zn, int *n)
+{
+ int err, exact;
+ struct ubifs_znode *znode;
+ unsigned long time = get_seconds();
+
+ dbg_tnc("search and dirty key %s", DBGKEY(key));
+
+ znode = c->zroot.znode;
+ if (unlikely(!znode)) {
+ znode = ubifs_load_znode(c, &c->zroot, NULL, 0);
+ if (IS_ERR(znode))
+ return PTR_ERR(znode);
+ }
+
+ znode = dirty_cow_znode(c, &c->zroot);
+ if (IS_ERR(znode))
+ return PTR_ERR(znode);
+
+ znode->time = time;
+
+ while (1) {
+ struct ubifs_zbranch *zbr;
+
+ exact = ubifs_search_zbranch(c, znode, key, n);
+
+ if (znode->level == 0)
+ break;
+
+ if (*n < 0)
+ *n = 0;
+ zbr = &znode->zbranch[*n];
+
+ if (zbr->znode) {
+ znode->time = time;
+ znode = dirty_cow_znode(c, zbr);
+ if (IS_ERR(znode))
+ return PTR_ERR(znode);
+ continue;
+ }
+
+ /* znode is not in TNC cache, load it from the media */
+ znode = ubifs_load_znode(c, zbr, znode, *n);
+ if (IS_ERR(znode))
+ return PTR_ERR(znode);
+ znode = dirty_cow_znode(c, zbr);
+ if (IS_ERR(znode))
+ return PTR_ERR(znode);
+ }
+
+ *zn = znode;
+ if (exact || !is_hash_key(c, key) || *n != -1) {
+ dbg_tnc("found %d, lvl %d, n %d", exact, znode->level, *n);
+ return exact;
+ }
+
+ /*
+ * See huge comment at 'lookup_level0_dirty()' what is the rest of the
+ * code.
+ */
+ err = tnc_prev(c, &znode, n);
+ if (err == -ENOENT) {
+ *n = -1;
+ dbg_tnc("found 0, lvl %d, n -1", znode->level);
+ return 0;
+ }
+ if (unlikely(err < 0))
+ return err;
+ if (keys_cmp(c, key, &znode->zbranch[*n].key)) {
+ *n = -1;
+ dbg_tnc("found 0, lvl %d, n -1", znode->level);
+ return 0;
+ }
+
+ if (znode->cnext || !ubifs_zn_dirty(znode)) {
+ znode = dirty_cow_bottom_up(c, znode);
+ if (IS_ERR(znode))
+ return PTR_ERR(znode);
+ }
+
+ dbg_tnc("found 1, lvl %d, n %d", znode->level, *n);
+ *zn = znode;
+ return 1;
+}
+
+/**
+ * ubifs_tnc_lookup - look up a file-system node.
+ * @c: UBIFS file-system description object
+ * @key: node key to lookup
+ * @node: the node is returned here
+ *
+ * This function look up and reads node with key @key. The caller has to make
+ * sure the @node buffer is large enough to fit the node. Returns zero in case
+ * of success, %-ENOENT if the node was not found, and a negative error code in
+ * case of failure.
+ */
+int ubifs_tnc_lookup(struct ubifs_info *c, const union ubifs_key *key,
+ void *node)
+{
+ int found, n, err;
+ struct ubifs_znode *znode;
+ struct ubifs_zbranch zbr, *zt;
+
+ mutex_lock(&c->tnc_mutex);
+ found = ubifs_lookup_level0(c, key, &znode, &n);
+ if (!found) {
+ err = -ENOENT;
+ goto out;
+ } else if (found < 0) {
+ err = found;
+ goto out;
+ }
+ zt = &znode->zbranch[n];
+ if (is_hash_key(c, key)) {
+ /*
+ * In this case the leaf node cache gets used, so we pass the
+ * address of the zbranch and keep the mutex locked
+ */
+ err = tnc_read_node_nm(c, zt, node);
+ goto out;
+ }
+ zbr = znode->zbranch[n];
+ mutex_unlock(&c->tnc_mutex);
+
+ err = ubifs_tnc_read_node(c, &zbr, node);
+ return err;
+
+out:
+ mutex_unlock(&c->tnc_mutex);
+ return err;
+}
+
+/**
+ * ubifs_tnc_locate - look up a file-system node and return it and its location.
+ * @c: UBIFS file-system description object
+ * @key: node key to lookup
+ * @node: the node is returned here
+ * @lnum: LEB number is returned here
+ * @offs: offset is returned here
+ *
+ * This function is the same as 'ubifs_tnc_lookup()' but it returns the node
+ * location also. See 'ubifs_tnc_lookup()'.
+ */
+int ubifs_tnc_locate(struct ubifs_info *c, const union ubifs_key *key,
+ void *node, int *lnum, int *offs)
+{
+ int found, n, err;
+ struct ubifs_znode *znode;
+ struct ubifs_zbranch zbr, *zt;
+
+ mutex_lock(&c->tnc_mutex);
+ found = ubifs_lookup_level0(c, key, &znode, &n);
+ if (!found) {
+ err = -ENOENT;
+ goto out;
+ } else if (found < 0) {
+ err = found;
+ goto out;
+ }
+ zt = &znode->zbranch[n];
+ if (is_hash_key(c, key)) {
+ /*
+ * In this case the leaf node cache gets used, so we pass the
+ * address of the zbranch and keep the mutex locked
+ */
+ *lnum = zt->lnum;
+ *offs = zt->offs;
+ err = tnc_read_node_nm(c, zt, node);
+ goto out;
+ }
+ zbr = znode->zbranch[n];
+ mutex_unlock(&c->tnc_mutex);
+
+ *lnum = zbr.lnum;
+ *offs = zbr.offs;
+
+ err = ubifs_tnc_read_node(c, &zbr, node);
+ return err;
+
+out:
+ mutex_unlock(&c->tnc_mutex);
+ return err;
+}
+
+/**
+ * do_lookup_nm- look up a "hashed" node.
+ * @c: UBIFS file-system description object
+ * @key: node key to lookup
+ * @node: the node is returned here
+ * @nm: node name
+ *
+ * This function look up and reads a node which contains name hash in the key.
+ * Since the hash may have collisions, there may be many nodes with the same
+ * key, so we have to sequentially look to all of them until the needed one is
+ * found. This function returns zero in case of success, %-ENOENT if the node
+ * was not found, and a negative error code in case of failure.
+ */
+static int do_lookup_nm(struct ubifs_info *c, const union ubifs_key *key,
+ void *node, const struct qstr *nm)
+{
+ int found, n, err;
+ struct ubifs_znode *znode;
+ struct ubifs_zbranch zbr;
+
+ dbg_tnc("name '%.*s' key %s", nm->len, nm->name, DBGKEY(key));
+ mutex_lock(&c->tnc_mutex);
+ found = ubifs_lookup_level0(c, key, &znode, &n);
+ if (!found) {
+ err = -ENOENT;
+ goto out_unlock;
+ } else if (found < 0) {
+ err = found;
+ goto out_unlock;
+ }
+
+ ubifs_assert(n >= 0);
+
+ err = resolve_collision(c, key, &znode, &n, nm);
+ dbg_tnc("rc returned %d, znode %p, n %d", err, znode, n);
+ if (unlikely(err < 0))
+ goto out_unlock;
+ if (err == 0) {
+ err = -ENOENT;
+ goto out_unlock;
+ }
+
+ zbr = znode->zbranch[n];
+ mutex_unlock(&c->tnc_mutex);
+
+ err = tnc_read_node_nm(c, &zbr, node);
+ return err;
+
+out_unlock:
+ mutex_unlock(&c->tnc_mutex);
+ return err;
+}
+
+/**
+ * ubifs_tnc_lookup_nm - look up a "hashed" node.
+ * @c: UBIFS file-system description object
+ * @key: node key to lookup
+ * @node: the node is returned here
+ * @nm: node name
+ *
+ * This function look up and reads a node which contains name hash in the key.
+ * Since the hash may have collisions, there may be many nodes with the same
+ * key, so we have to sequentially look to all of them until the needed one is
+ * found. This function returns zero in case of success, %-ENOENT if the node
+ * was not found, and a negative error code in case of failure.
+ */
+int ubifs_tnc_lookup_nm(struct ubifs_info *c, const union ubifs_key *key,
+ void *node, const struct qstr *nm)
+{
+ int err, len;
+ const struct ubifs_dent_node *dent = node;
+
+ /*
+ * We assume that in most of the cases there are no name collisions and
+ * 'ubifs_tnc_lookup()' returns us the right direntry.
+ */
+ err = ubifs_tnc_lookup(c, key, node);
+ if (err)
+ return err;
+
+ len = le16_to_cpu(dent->nlen);
+ if (nm->len == len && !memcmp(dent->name, nm->name, len))
+ return 0;
+
+ /*
+ * Unluckily, there are hash collisions and we have to iterate over
+ * them look at each direntry with colliding name hash sequentially.
+ */
+ return do_lookup_nm(c, key, node, nm);
+}
+
+/**
+ * correct_parent_keys - correct parent znodes' keys.
+ * @c: UBIFS file-system description object
+ * @znode: znode to correct parent znodes for
+ *
+ * This is a helper function for 'tnc_insert()'. When the key of the leftmost
+ * zbranch changes, keys of parent znodes have to be corrected. This helper
+ * function is called in such situations and corrects the keys if needed.
+ */
+static void correct_parent_keys(const struct ubifs_info *c,
+ struct ubifs_znode *znode)
+{
+ union ubifs_key *key, *key1;
+
+ ubifs_assert(znode->parent);
+ ubifs_assert(znode->iip == 0);
+
+ key = &znode->zbranch[0].key;
+ key1 = &znode->parent->zbranch[0].key;
+
+ while (keys_cmp(c, key, key1) < 0) {
+ key_copy(c, key, key1);
+ znode = znode->parent;
+ znode->alt = 1;
+ if (!znode->parent || znode->iip)
+ break;
+ key1 = &znode->parent->zbranch[0].key;
+ }
+}
+
+/**
+ * insert_zbranch - insert a zbranch into a znode.
+ * @znode: znode into which to insert
+ * @zbr: zbranch to insert
+ * @n: slot number to insert to
+ *
+ * This is a helper function for 'tnc_insert()'. UBIFS does not allow "gaps" in
+ * znode's array of zbranches and keeps zbranches consolidated, so when a new
+ * zbranch has to be inserted to the @znode->zbranches[]' array at the @n-th
+ * slot, zbranches starting from @n have to be moved right.
+ */
+static void insert_zbranch(struct ubifs_znode *znode,
+ const struct ubifs_zbranch *zbr, int n)
+{
+ int i;
+
+ ubifs_assert(ubifs_zn_dirty(znode));
+
+ if (znode->level) {
+ for (i = znode->child_cnt; i > n; i--) {
+ znode->zbranch[i] = znode->zbranch[i - 1];
+ if (znode->zbranch[i].znode)
+ znode->zbranch[i].znode->iip = i;
+ }
+ if (zbr->znode)
+ zbr->znode->iip = n;
+ } else
+ for (i = znode->child_cnt; i > n; i--)
+ znode->zbranch[i] = znode->zbranch[i - 1];
+
+ znode->zbranch[n] = *zbr;
+ znode->child_cnt += 1;
+
+ /*
+ * After inserting at slot zero, the lower bound of the key range of
+ * this znode may have changed. If this znode is subsequently split
+ * then the upper bound of the key range may change, and furthermore
+ * it could change to be lower than the original lower bound. If that
+ * happens, then it will no longer be possible to find this znode in the
+ * TNC using the key from the index node on flash. That is bad because
+ * if it is not found, we will assume it is obsolete and may overwrite
+ * it. Then if there is an unclean unmount, we will start using the
+ * old index which will be broken.
+ *
+ * So we first mark znodes that have insertions at slot zero, and then
+ * if they are split we add their lnum/offs to the old_idx tree.
+ */
+ if (n == 0)
+ znode->alt = 1;
+}
+
+/**
+ * tnc_insert - insert a node into TNC.
+ * @c: UBIFS file-system description object
+ * @znode: znode to insert into
+ * @zbr: branch to insert
+ * @n: slot number to insert new zbranch to
+ *
+ * This function inserts a new node described by @zbr into znode @znode. If
+ * znode does not have a free slot for new zbranch, it is split. Parent znodes
+ * are splat as well if needed. Returns zero in case of success or a negative
+ * error code in case of failure.
+ */
+static int tnc_insert(struct ubifs_info *c, struct ubifs_znode *znode,
+ struct ubifs_zbranch *zbr, int n)
+{
+ struct ubifs_znode *zn, *zi, *zp;
+ int i, keep, move, appending = 0;
+ union ubifs_key *key = &zbr->key;
+
+ ubifs_assert(n >= 0 && n <= c->fanout);
+
+ /* Implement naive insert for now */
+again:
+ zp = znode->parent;
+ if (znode->child_cnt < c->fanout) {
+ ubifs_assert(n != c->fanout);
+ dbg_tnc("inserted at %d level %d, key %s", n, znode->level,
+ DBGKEY(key));
+
+ insert_zbranch(znode, zbr, n);
+
+ /* Ensure parent's key is correct */
+ if (n == 0 && zp && znode->iip == 0)
+ correct_parent_keys(c, znode);
+
+ return 0;
+ }
+
+ /*
+ * Unfortunately, @znode does not have more empty slots and we have to
+ * split it.
+ */
+ dbg_tnc("splitting level %d, key %s", znode->level, DBGKEY(key));
+
+ if (znode->alt)
+ /*
+ * We can no longer be sure of finding this znode by key, so we
+ * record it in the old_idx tree.
+ */
+ ins_clr_old_idx_znode(c, znode);
+
+ zn = kzalloc(c->max_znode_sz, GFP_NOFS);
+ if (!zn)
+ return -ENOMEM;
+ zn->parent = zp;
+ zn->level = znode->level;
+
+ /* Decide where to split */
+ if (znode->level == 0 && n == c->fanout &&
+ key_type(c, key) == UBIFS_DATA_KEY) {
+ union ubifs_key *key1;
+
+ /*
+ * If this is an inode which is being appended - do not split
+ * it because no other zbranches can be inserted between
+ * zbranches of consecutive data nodes anyway.
+ */
+ key1 = &znode->zbranch[n - 1].key;
+ if (key_inum(c, key1) == key_inum(c, key) &&
+ key_type(c, key1) == UBIFS_DATA_KEY &&
+ key_block(c, key1) == key_block(c, key) - 1)
+ appending = 1;
+ }
+
+ if (appending) {
+ keep = c->fanout;
+ move = 0;
+ } else {
+ keep = (c->fanout + 1) / 2;
+ move = c->fanout - keep;
+ }
+
+ /*
+ * Although we don't at present, we could look at the neighbors and see
+ * if we can move some zbranches there.
+ */
+
+ if (n < keep) {
+ /* Insert into existing znode */
+ zi = znode;
+ move += 1;
+ keep -= 1;
+ } else {
+ /* Insert into new znode */
+ zi = zn;
+ n -= keep;
+ /* Re-parent */
+ if (zn->level != 0)
+ zbr->znode->parent = zn;
+ }
+
+ __set_bit(DIRTY_ZNODE, &zn->flags);
+ atomic_long_inc(&c->dirty_zn_cnt);
+
+ zn->child_cnt = move;
+ znode->child_cnt = keep;
+
+ dbg_tnc("moving %d, keeping %d", move, keep);
+
+ /* Move zbranch */
+ for (i = 0; i < move; i++) {
+ zn->zbranch[i] = znode->zbranch[keep + i];
+ /* Re-parent */
+ if (zn->level != 0)
+ if (zn->zbranch[i].znode) {
+ zn->zbranch[i].znode->parent = zn;
+ zn->zbranch[i].znode->iip = i;
+ }
+ }
+
+ /* Insert new key and branch */
+ dbg_tnc("inserting at %d level %d, key %s", n, zn->level, DBGKEY(key));
+
+ insert_zbranch(zi, zbr, n);
+
+ /* Insert new znode (produced by spitting) into the parent */
+ if (zp) {
+ i = n;
+ /* Locate insertion point */
+ n = znode->iip + 1;
+ if (appending && n != c->fanout)
+ appending = 0;
+
+ if (i == 0 && zi == znode && znode->iip == 0)
+ correct_parent_keys(c, znode);
+
+ /* Tail recursion */
+ zbr->key = zn->zbranch[0].key;
+ zbr->znode = zn;
+ zbr->lnum = 0;
+ zbr->offs = 0;
+ zbr->len = 0;
+ znode = zp;
+
+ goto again;
+ }
+
+ /* We have to split root znode */
+ dbg_tnc("creating new zroot at level %d", znode->level + 1);
+
+ zi = kzalloc(c->max_znode_sz, GFP_NOFS);
+ if (!zi)
+ return -ENOMEM;
+
+ zi->child_cnt = 2;
+ zi->level = znode->level + 1;
+
+ __set_bit(DIRTY_ZNODE, &zi->flags);
+ atomic_long_inc(&c->dirty_zn_cnt);
+
+ zi->zbranch[0].key = znode->zbranch[0].key;
+ zi->zbranch[0].znode = znode;
+ zi->zbranch[0].lnum = c->zroot.lnum;
+ zi->zbranch[0].offs = c->zroot.offs;
+ zi->zbranch[0].len = c->zroot.len;
+ zi->zbranch[1].key = zn->zbranch[0].key;
+ zi->zbranch[1].znode = zn;
+
+ c->zroot.lnum = 0;
+ c->zroot.offs = 0;
+ c->zroot.len = 0;
+ c->zroot.znode = zi;
+
+ zn->parent = zi;
+ zn->iip = 1;
+ znode->parent = zi;
+ znode->iip = 0;
+
+ return 0;
+}
+
+/**
+ * ubifs_tnc_add - add a node to TNC.
+ * @c: UBIFS file-system description object
+ * @key: key to add
+ * @lnum: LEB number of node
+ * @offs: node offset
+ * @len: node length
+ *
+ * This function adds a node with key @key to TNC. The node may be new or it may
+ * obsolete some existing one. Returns %0 on success or negative error code on
+ * failure.
+ */
+int ubifs_tnc_add(struct ubifs_info *c, const union ubifs_key *key, int lnum,
+ int offs, int len)
+{
+ int found, n, err = 0;
+ struct ubifs_znode *znode;
+
+ mutex_lock(&c->tnc_mutex);
+ dbg_tnc("%d:%d, len %d, key %s", lnum, offs, len, DBGKEY(key));
+ found = lookup_level0_dirty(c, key, &znode, &n);
+ if (!found) {
+ struct ubifs_zbranch zbr;
+
+ zbr.znode = NULL;
+ zbr.lnum = lnum;
+ zbr.offs = offs;
+ zbr.len = len;
+ key_copy(c, key, &zbr.key);
+ err = tnc_insert(c, znode, &zbr, n + 1);
+ } else if (found == 1) {
+ struct ubifs_zbranch *zbr = &znode->zbranch[n];
+
+ lnc_free(zbr);
+ err = ubifs_add_dirt(c, zbr->lnum, zbr->len);
+ zbr->lnum = lnum;
+ zbr->offs = offs;
+ zbr->len = len;
+ } else
+ err = found;
+ if (!err)
+ err = dbg_check_tnc(c, 0);
+ mutex_unlock(&c->tnc_mutex);
+
+ return err;
+}
+
+/**
+ * ubifs_tnc_replace - replace a node in the TNC only if the old node is found.
+ * @c: UBIFS file-system description object
+ * @key: key to add
+ * @old_lnum: LEB number of old node
+ * @old_offs: old node offset
+ * @lnum: LEB number of node
+ * @offs: node offset
+ * @len: node length
+ *
+ * This function replaces a node with key @key in the TNC only if the old node
+ * is found. This function is called by garbage collection when node are moved.
+ * Returns %0 on success or negative error code on failure.
+ */
+int ubifs_tnc_replace(struct ubifs_info *c, const union ubifs_key *key,
+ int old_lnum, int old_offs, int lnum, int offs, int len)
+{
+ int found, n, err = 0;
+ struct ubifs_znode *znode;
+
+ mutex_lock(&c->tnc_mutex);
+ dbg_tnc("old LEB %d:%d, new LEB %d:%d, len %d, key %s", old_lnum,
+ old_offs, lnum, offs, len, DBGKEY(key));
+ found = lookup_level0_dirty(c, key, &znode, &n);
+ if (found < 0) {
+ err = found;
+ goto out_unlock;
+ }
+
+ if (found == 1) {
+ struct ubifs_zbranch *zbr = &znode->zbranch[n];
+
+ found = 0;
+ if (zbr->lnum == old_lnum && zbr->offs == old_offs) {
+ lnc_free(zbr);
+ err = ubifs_add_dirt(c, zbr->lnum, zbr->len);
+ if (err)
+ goto out_unlock;
+ zbr->lnum = lnum;
+ zbr->offs = offs;
+ zbr->len = len;
+ found = 1;
+ } else if (is_hash_key(c, key)) {
+ found = resolve_collision_directly(c, key, &znode, &n,
+ old_lnum, old_offs);
+ dbg_tnc("rc returned %d, znode %p, n %d, LEB %d:%d",
+ found, znode, n, old_lnum, old_offs);
+ if (found < 0) {
+ err = found;
+ goto out_unlock;
+ }
+
+ if (found) {
+ /* Ensure the znode is dirtied */
+ if (znode->cnext || !ubifs_zn_dirty(znode)) {
+ znode = dirty_cow_bottom_up(c,
+ znode);
+ if (IS_ERR(znode)) {
+ err = PTR_ERR(znode);
+ goto out_unlock;
+ }
+ }
+ zbr = &znode->zbranch[n];
+ lnc_free(zbr);
+ err = ubifs_add_dirt(c, zbr->lnum,
+ zbr->len);
+ if (err)
+ goto out_unlock;
+ zbr->lnum = lnum;
+ zbr->offs = offs;
+ zbr->len = len;
+ }
+ }
+ }
+
+ if (!found)
+ err = ubifs_add_dirt(c, lnum, len);
+
+ if (!err)
+ err = dbg_check_tnc(c, 0);
+
+out_unlock:
+ mutex_unlock(&c->tnc_mutex);
+ return err;
+}
+
+/**
+ * ubifs_tnc_add_nm - add a "hashed" node to TNC.
+ * @c: UBIFS file-system description object
+ * @key: key to add
+ * @lnum: LEB number of node
+ * @offs: node offset
+ * @len: node length
+ * @nm: node name
+ *
+ * This is the same as 'ubifs_tnc_add()' but it should be used with keys which
+ * may have collisions, like directory entry keys.
+ */
+int ubifs_tnc_add_nm(struct ubifs_info *c, const union ubifs_key *key,
+ int lnum, int offs, int len, const struct qstr *nm)
+{
+ int found, n, err = 0;
+ struct ubifs_znode *znode;
+
+ mutex_lock(&c->tnc_mutex);
+ dbg_tnc("LEB %d:%d, name '%.*s', key %s", lnum, offs, nm->len, nm->name,
+ DBGKEY(key));
+ found = lookup_level0_dirty(c, key, &znode, &n);
+ if (found < 0) {
+ err = found;
+ goto out_unlock;
+ }
+
+ if (found == 1) {
+ if (c->replaying)
+ found = fallible_resolve_collision(c, key, &znode, &n,
+ nm, 1);
+ else
+ found = resolve_collision(c, key, &znode, &n, nm);
+ dbg_tnc("rc returned %d, znode %p, n %d", found, znode, n);
+ if (found < 0) {
+ err = found;
+ goto out_unlock;
+ }
+
+ /* Ensure the znode is dirtied */
+ if (znode->cnext || !ubifs_zn_dirty(znode)) {
+ znode = dirty_cow_bottom_up(c, znode);
+ if (IS_ERR(znode)) {
+ err = PTR_ERR(znode);
+ goto out_unlock;
+ }
+ }
+
+ if (found == 1) {
+ struct ubifs_zbranch *zbr = &znode->zbranch[n];
+
+ lnc_free(zbr);
+ err = ubifs_add_dirt(c, zbr->lnum, zbr->len);
+ zbr->lnum = lnum;
+ zbr->offs = offs;
+ zbr->len = len;
+ goto out_unlock;
+ }
+ }
+
+ if (!found) {
+ struct ubifs_zbranch zbr;
+
+ zbr.znode = NULL;
+ zbr.lnum = lnum;
+ zbr.offs = offs;
+ zbr.len = len;
+ key_copy(c, key, &zbr.key);
+ err = tnc_insert(c, znode, &zbr, n + 1);
+ if (err)
+ goto out_unlock;
+ if (c->replaying) {
+ /*
+ * We did not find it in the index so there may be a
+ * dangling branch still in the index. So we remove it
+ * by passing 'ubifs_tnc_remove_nm()' the same key but
+ * an unmatchable name.
+ */
+ struct qstr noname = { .len = 0, .name = "" };
+
+ err = dbg_check_tnc(c, 0);
+ mutex_unlock(&c->tnc_mutex);
+ if (err)
+ return err;
+ return ubifs_tnc_remove_nm(c, key, &noname);
+ }
+ }
+
+out_unlock:
+ if (!err)
+ err = dbg_check_tnc(c, 0);
+ mutex_unlock(&c->tnc_mutex);
+ return err;
+}
+
+/**
+ * tnc_delete - delete a znode form TNC.
+ * @c: UBIFS file-system description object
+ * @znode: znode to delete from
+ * @n: zbranch slot number to delete
+ *
+ * This function deletes a leaf node from @n-th slot of @znode. Returns zero in
+ * case of success and a negative error code in case of failure.
+ */
+static int tnc_delete(struct ubifs_info *c, struct ubifs_znode *znode, int n)
+{
+ struct ubifs_zbranch *zbr;
+ struct ubifs_znode *zp;
+ int i, err;
+
+ /* Delete without merge for now */
+ ubifs_assert(znode->level == 0);
+ ubifs_assert(n >= 0 && n < c->fanout);
+ dbg_tnc("deleting %s", DBGKEY(&znode->zbranch[n].key));
+
+ zbr = &znode->zbranch[n];
+ lnc_free(zbr);
+
+ err = ubifs_add_dirt(c, zbr->lnum, zbr->len);
+ if (err) {
+ dbg_dump_znode(c, znode);
+ return err;
+ }
+
+ /* We do not "gap" zbranch slots */
+ for (i = n; i < znode->child_cnt - 1; i++)
+ znode->zbranch[i] = znode->zbranch[i + 1];
+ znode->child_cnt -= 1;
+
+ if (znode->child_cnt > 0)
+ return 0;
+
+ /*
+ * This was the last zbranch, we have to delete this znode from the
+ * parent.
+ */
+
+ do {
+ ubifs_assert(!test_bit(OBSOLETE_ZNODE, &znode->flags));
+ ubifs_assert(ubifs_zn_dirty(znode));
+
+ zp = znode->parent;
+ n = znode->iip;
+
+ atomic_long_dec(&c->dirty_zn_cnt);
+
+ err = insert_old_idx_znode(c, znode);
+ if (err)
+ return err;
+
+ if (znode->cnext) {
+ __set_bit(OBSOLETE_ZNODE, &znode->flags);
+ atomic_long_inc(&c->clean_zn_cnt);
+ atomic_long_inc(&ubifs_clean_zn_cnt);
+ } else
+ kfree(znode);
+ znode = zp;
+ } while (znode->child_cnt == 1); /* while removing last child */
+
+ /* Remove from znode, entry n - 1 */
+ znode->child_cnt -= 1;
+ ubifs_assert(znode->level != 0);
+ for (i = n; i < znode->child_cnt; i++) {
+ znode->zbranch[i] = znode->zbranch[i + 1];
+ if (znode->zbranch[i].znode)
+ znode->zbranch[i].znode->iip = i;
+ }
+
+ /*
+ * If this is the root and it has only 1 child then
+ * collapse the tree.
+ */
+ if (!znode->parent) {
+ while (znode->child_cnt == 1 && znode->level != 0) {
+ zp = znode;
+ zbr = &znode->zbranch[0];
+ znode = get_znode(c, znode, 0);
+ if (IS_ERR(znode))
+ return PTR_ERR(znode);
+ znode = dirty_cow_znode(c, zbr);
+ if (IS_ERR(znode))
+ return PTR_ERR(znode);
+ znode->parent = NULL;
+ znode->iip = 0;
+ if (c->zroot.len) {
+ err = insert_old_idx(c, c->zroot.lnum,
+ c->zroot.offs);
+ if (err)
+ return err;
+ }
+ c->zroot.lnum = zbr->lnum;
+ c->zroot.offs = zbr->offs;
+ c->zroot.len = zbr->len;
+ c->zroot.znode = znode;
+ ubifs_assert(!test_bit(OBSOLETE_ZNODE,
+ &zp->flags));
+ ubifs_assert(test_bit(DIRTY_ZNODE, &zp->flags));
+ atomic_long_dec(&c->dirty_zn_cnt);
+
+ if (zp->cnext) {
+ __set_bit(OBSOLETE_ZNODE, &zp->flags);
+ atomic_long_inc(&c->clean_zn_cnt);
+ atomic_long_inc(&ubifs_clean_zn_cnt);
+ } else
+ kfree(zp);
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * ubifs_tnc_remove - remove an index entry of a node.
+ * @c: UBIFS file-system description object
+ * @key: key of node
+ *
+ * Returns %0 on success or negative error code on failure.
+ */
+int ubifs_tnc_remove(struct ubifs_info *c, const union ubifs_key *key)
+{
+ int found, n, err = 0;
+ struct ubifs_znode *znode;
+
+ mutex_lock(&c->tnc_mutex);
+ dbg_tnc("key %s", DBGKEY(key));
+ found = lookup_level0_dirty(c, key, &znode, &n);
+ if (found < 0) {
+ err = found;
+ goto out_unlock;
+ }
+ if (found == 1)
+ err = tnc_delete(c, znode, n);
+ if (!err)
+ err = dbg_check_tnc(c, 0);
+
+out_unlock:
+ mutex_unlock(&c->tnc_mutex);
+ return err;
+}
+
+/**
+ * ubifs_tnc_remove_nm - remove an index entry for a "hashed" node.
+ * @c: UBIFS file-system description object
+ * @key: key of node
+ * @nm: directory entry name
+ *
+ * Returns %0 on success or negative error code on failure.
+ */
+int ubifs_tnc_remove_nm(struct ubifs_info *c, const union ubifs_key *key,
+ const struct qstr *nm)
+{
+ int n, err;
+ struct ubifs_znode *znode;
+
+ mutex_lock(&c->tnc_mutex);
+ dbg_tnc("%.*s, key %s", nm->len, nm->name, DBGKEY(key));
+ err = lookup_level0_dirty(c, key, &znode, &n);
+ if (err < 0)
+ goto out_unlock;
+
+ if (err) {
+ if (c->replaying)
+ err = fallible_resolve_collision(c, key, &znode, &n,
+ nm, 0);
+ else
+ err = resolve_collision(c, key, &znode, &n, nm);
+ dbg_tnc("rc returned %d, znode %p, n %d", err, znode, n);
+ if (err < 0)
+ goto out_unlock;
+ if (err) {
+ /* Ensure the znode is dirtied */
+ if (znode->cnext || !ubifs_zn_dirty(znode)) {
+ znode = dirty_cow_bottom_up(c, znode);
+ if (IS_ERR(znode)) {
+ err = PTR_ERR(znode);
+ goto out_unlock;
+ }
+ }
+ err = tnc_delete(c, znode, n);
+ }
+ }
+
+out_unlock:
+ if (!err)
+ err = dbg_check_tnc(c, 0);
+ mutex_unlock(&c->tnc_mutex);
+ return err;
+}
+
+/**
+ * key_in_range - determine if a key falls within a range of keys.
+ * @c: UBIFS file-system description object
+ * @key: key to check
+ * @from_key: lowest key in range
+ * @to_key: highest key in range
+ *
+ * This function returns %1 if the key is in range and %0 otherwise.
+ */
+static int key_in_range(struct ubifs_info *c, union ubifs_key *key,
+ union ubifs_key *from_key, union ubifs_key *to_key)
+{
+ if (keys_cmp(c, key, from_key) < 0)
+ return 0;
+ if (keys_cmp(c, key, to_key) > 0)
+ return 0;
+ return 1;
+}
+
+/**
+ * ubifs_tnc_remove_range - remove index entries in range.
+ * @c: UBIFS file-system description object
+ * @from_key: lowest key to remove
+ * @to_key: highest key to remove
+ *
+ * This function removes index entries starting at @from_key and ending at
+ * @to_key. This function returns zero in case of success and a negative error
+ * code in case of failure.
+ */
+int ubifs_tnc_remove_range(struct ubifs_info *c, union ubifs_key *from_key,
+ union ubifs_key *to_key)
+{
+ int i, n, k, err = 0;
+ struct ubifs_znode *znode;
+ union ubifs_key *key;
+
+ mutex_lock(&c->tnc_mutex);
+ while (1) {
+ /* Find first level 0 znode that contains keys to remove */
+ err = ubifs_lookup_level0(c, from_key, &znode, &n);
+ if (err < 0)
+ goto out_unlock;
+
+ if (err)
+ key = from_key;
+ else {
+ err = tnc_next(c, &znode, &n);
+ if (err == -ENOENT) {
+ err = 0;
+ goto out_unlock;
+ }
+ if (err < 0)
+ goto out_unlock;
+ key = &znode->zbranch[n].key;
+ if (!key_in_range(c, key, from_key, to_key)) {
+ err = 0;
+ goto out_unlock;
+ }
+ }
+
+ /* Ensure the znode is dirtied */
+ if (znode->cnext || !ubifs_zn_dirty(znode)) {
+ znode = dirty_cow_bottom_up(c, znode);
+ if (IS_ERR(znode)) {
+ err = PTR_ERR(znode);
+ goto out_unlock;
+ }
+ }
+
+ /* Remove all keys in range except the first */
+ for (i = n + 1, k = 0; i < znode->child_cnt; i++, k++) {
+ key = &znode->zbranch[i].key;
+ if (!key_in_range(c, key, from_key, to_key))
+ break;
+ lnc_free(&znode->zbranch[i]);
+ err = ubifs_add_dirt(c, znode->zbranch[i].lnum,
+ znode->zbranch[i].len);
+ if (err) {
+ dbg_dump_znode(c, znode);
+ goto out_unlock;
+ }
+ dbg_tnc("removing %s", DBGKEY(key));
+ }
+ if (k) {
+ for (i = n + 1 + k; i < znode->child_cnt; i++)
+ znode->zbranch[i - k] = znode->zbranch[i];
+ znode->child_cnt -= k;
+ }
+
+ /* Now delete the first */
+ err = tnc_delete(c, znode, n);
+ if (err)
+ goto out_unlock;
+ }
+
+out_unlock:
+ if (!err)
+ err = dbg_check_tnc(c, 0);
+ mutex_unlock(&c->tnc_mutex);
+ return err;
+}
+
+/**
+ * ubifs_tnc_remove_ino - remove an inode from TNC.
+ * @c: UBIFS file-system description object
+ * @inum: inode number to remove
+ *
+ * This function remove inode @inum and all the extended attributes associated
+ * with the anode from TNC and returns zero in case of success or a negative
+ * error code in case of failure.
+ */
+int ubifs_tnc_remove_ino(struct ubifs_info *c, ino_t inum)
+{
+ union ubifs_key key1, key2;
+ struct ubifs_dent_node *xent, *pxent = NULL;
+ struct qstr nm = { .name = NULL };
+
+ dbg_tnc("ino %lu", inum);
+
+ /*
+ * Walk all extended attribute entries and remove them together with
+ * corresponding extended attribute inodes.
+ */
+ lowest_xent_key(c, &key1, inum);
+ while (1) {
+ ino_t xattr_inum;
+ int err;
+
+ xent = ubifs_tnc_next_ent(c, &key1, &nm);
+ if (IS_ERR(xent)) {
+ err = PTR_ERR(xent);
+ if (err == -ENOENT)
+ break;
+ return err;
+ }
+
+ xattr_inum = le64_to_cpu(xent->inum);
+ dbg_tnc("xent '%s', ino %lu", xent->name, xattr_inum);
+
+ nm.name = xent->name;
+ nm.len = le16_to_cpu(xent->nlen);
+ err = ubifs_tnc_remove_nm(c, &key1, &nm);
+ if (err) {
+ kfree(xent);
+ return err;
+ }
+
+ lowest_ino_key(c, &key1, xattr_inum);
+ highest_ino_key(c, &key2, xattr_inum);
+ err = ubifs_tnc_remove_range(c, &key1, &key2);
+ if (err) {
+ kfree(xent);
+ return err;
+ }
+
+ kfree(pxent);
+ pxent = xent;
+ key_read(c, &xent->key, &key1);
+ }
+
+ kfree(pxent);
+ lowest_ino_key(c, &key1, inum);
+ highest_ino_key(c, &key2, inum);
+
+ return ubifs_tnc_remove_range(c, &key1, &key2);
+}
+
+/**
+ * ubifs_tnc_next_ent - walk directory or extended attribute entries.
+ * @c: UBIFS file-system description object
+ * @key: key of last entry
+ * @nm: name of last entry found or %NULL
+ *
+ * This function finds and reads the next directory or extended attribute entry
+ * after the given key (@key) if there is one. @nm is used to resolve
+ * collisions.
+ *
+ * If the name of the current entry is not known and only the key is known,
+ * @nm->name has to be %NULL. In this case the semantics of this function is a
+ * little bit different and it returns the entry corresponding to this key, not
+ * the next one. If the key was not found, the closest "right" entry is
+ * returned.
+ *
+ * If the fist entry has to be found, @key has to contain the lowest possible
+ * key value for this inode and @name has to be %NULL.
+ *
+ * This function returns the found directory or extended attribute entry node
+ * in case of success, %-ENOENT is returned if no entry was found, and a
+ * negative error code is returned in case of failure.
+ */
+struct ubifs_dent_node *ubifs_tnc_next_ent(struct ubifs_info *c,
+ union ubifs_key *key,
+ const struct qstr *nm)
+{
+ int n, err, type = key_type(c, key);
+ struct ubifs_znode *znode;
+ struct ubifs_dent_node *dent;
+ struct ubifs_zbranch *zbr;
+ union ubifs_key *dkey;
+
+ dbg_tnc("%s %s", nm->name ? (char *)nm->name : "(lowest)", DBGKEY(key));
+ ubifs_assert(is_hash_key(c, key));
+
+ mutex_lock(&c->tnc_mutex);
+ err = ubifs_lookup_level0(c, key, &znode, &n);
+ if (unlikely(err < 0))
+ goto out_unlock;
+
+ if (nm->name) {
+ if (err) {
+ /* Handle collisions */
+ err = resolve_collision(c, key, &znode, &n, nm);
+ dbg_tnc("rc returned %d, znode %p, n %d",
+ err, znode, n);
+ if (unlikely(err < 0))
+ goto out_unlock;
+ }
+
+ /* Now find next entry */
+ err = tnc_next(c, &znode, &n);
+ if (unlikely(err))
+ goto out_unlock;
+ } else {
+ /*
+ * The full name of the entry was not given, in which case the
+ * behavior of this function is a little different and it
+ * returns current entry, not the next one.
+ */
+ if (!err) {
+ /*
+ * However, the given key does not exist in the TNC
+ * tree and @znode/@n variables contain the closest
+ * "preceding" element. Switch to the next one.
+ */
+ err = tnc_next(c, &znode, &n);
+ if (err)
+ goto out_unlock;
+ }
+ }
+
+ zbr = &znode->zbranch[n];
+ dent = kmalloc(zbr->len, GFP_NOFS);
+ if (unlikely(!dent)) {
+ err = -ENOMEM;
+ goto out_unlock;
+ }
+
+ /*
+ * The above 'tnc_next()' call could lead us to the next inode, check
+ * this.
+ */
+ dkey = &zbr->key;
+ if (key_inum(c, dkey) != key_inum(c, key) ||
+ key_type(c, dkey) != type) {
+ err = -ENOENT;
+ goto out_free;
+ }
+
+ err = tnc_read_node_nm(c, zbr, dent);
+ if (unlikely(err))
+ goto out_free;
+
+ mutex_unlock(&c->tnc_mutex);
+ return dent;
+
+out_free:
+ kfree(dent);
+out_unlock:
+ mutex_unlock(&c->tnc_mutex);
+ return ERR_PTR(err);
+}
+
+/**
+ * tnc_destroy_cnext - destroy left-over obsolete znodes from a failed commit.
+ * @c: UBIFS file-system description object
+ *
+ * Destroy left-over obsolete znodes from a failed commit.
+ */
+static void tnc_destroy_cnext(struct ubifs_info *c)
+{
+ struct ubifs_znode *cnext;
+
+ if (!c->cnext)
+ return;
+ ubifs_assert(c->cmt_state == COMMIT_BROKEN);
+ cnext = c->cnext;
+ do {
+ struct ubifs_znode *znode = cnext;
+
+ cnext = cnext->cnext;
+ if (test_bit(OBSOLETE_ZNODE, &znode->flags))
+ kfree(znode);
+ } while (cnext && cnext != c->cnext);
+}
+
+/**
+ * ubifs_tnc_close - close TNC subsystem and free all related resources.
+ * @c: UBIFS file-system description object
+ */
+void ubifs_tnc_close(struct ubifs_info *c)
+{
+ long clean_freed;
+
+ tnc_destroy_cnext(c);
+ if (c->zroot.znode) {
+ clean_freed = ubifs_destroy_tnc_subtree(c->zroot.znode);
+ atomic_long_sub(clean_freed, &ubifs_clean_zn_cnt);
+ }
+ kfree(c->gap_lebs);
+ kfree(c->ilebs);
+ destroy_old_idx(c);
+}
+
+/**
+ * left_znode - get the znode to the left.
+ * @c: UBIFS file-system description object
+ * @znode: znode
+ *
+ * This function returns a pointer to the znode to the left of @znode or NULL if
+ * there is not one. A negative error code is returned on failure.
+ */
+static struct ubifs_znode *left_znode(struct ubifs_info *c,
+ struct ubifs_znode *znode)
+{
+ int level = znode->level;
+
+ while (1) {
+ int n = znode->iip - 1;
+
+ /* Go up until we can go left */
+ znode = znode->parent;
+ if (!znode)
+ return NULL;
+ if (n >= 0) {
+ /* Now go down the rightmost branch to 'level' */
+ znode = get_znode(c, znode, n);
+ if (IS_ERR(znode))
+ return znode;
+ while (znode->level != level) {
+ n = znode->child_cnt - 1;
+ znode = get_znode(c, znode, n);
+ if (IS_ERR(znode))
+ return znode;
+ }
+ break;
+ }
+ }
+ return znode;
+}
+
+/**
+ * right_znode - get the znode to the right.
+ * @c: UBIFS file-system description object
+ * @znode: znode
+ *
+ * This function returns a pointer to the znode to the right of @znode or NULL
+ * if there is not one. A negative error code is returned on failure.
+ */
+static struct ubifs_znode *right_znode(struct ubifs_info *c,
+ struct ubifs_znode *znode)
+{
+ int level = znode->level;
+
+ while (1) {
+ int n = znode->iip + 1;
+
+ /* Go up until we can go right */
+ znode = znode->parent;
+ if (!znode)
+ return NULL;
+ if (n < znode->child_cnt) {
+ /* Now go down the leftmost branch to 'level' */
+ znode = get_znode(c, znode, n);
+ if (IS_ERR(znode))
+ return znode;
+ while (znode->level != level) {
+ znode = get_znode(c, znode, 0);
+ if (IS_ERR(znode))
+ return znode;
+ }
+ break;
+ }
+ }
+ return znode;
+}
+
+/**
+ * lookup_znode - find a particular indexing node from TNC.
+ * @c: UBIFS file-system description object
+ * @key: index node key to lookup
+ * @level: index node level
+ * @lnum: index node LEB number
+ * @offs: index node offset
+ *
+ * This function searches an indexing node by its first key @key and its
+ * address @lnum:@offs. It looks up the indexing tree by pulling all indexing
+ * nodes it traverses to TNC. This function is called fro indexing nodes which
+ * were found on the media by scanning, for example when garbage-collecting or
+ * when doing in-the-gaps commit. This means that the indexing node which is
+ * looked for does not have to have exactly the same leftmost key @key, because
+ * the leftmost key may have been changed, in which case TNC will contain a
+ * dirty znode which still refers the same @lnum:@offs. This function is clever
+ * enough to recognize such indexing nodes.
+ *
+ * Note, if a znode was deleted or changed too much, then this function will
+ * not find it. For situations like this UBIFS has the old index RB-tree
+ * (indexed by @lnum:@offs).
+ *
+ * This function returns a pointer to the znode found or %NULL if it is not
+ * found. A negative error code is returned on failure.
+ */
+static struct ubifs_znode *lookup_znode(struct ubifs_info *c,
+ union ubifs_key *key, int level,
+ int lnum, int offs)
+{
+ struct ubifs_znode *znode, *zn;
+ int n, nn;
+
+ /*
+ * The arguments have probably been read off flash, so don't assume
+ * they are valid.
+ */
+ if (level < 0)
+ return ERR_PTR(-EINVAL);
+
+ /* Get the root znode */
+ znode = c->zroot.znode;
+ if (!znode) {
+ znode = ubifs_load_znode(c, &c->zroot, NULL, 0);
+ if (IS_ERR(znode))
+ return znode;
+ }
+ /* Check if it is the one we are looking for */
+ if (c->zroot.lnum == lnum && c->zroot.offs == offs)
+ return znode;
+ /* Descend to the parent level i.e. (level + 1) */
+ if (level >= znode->level)
+ return NULL;
+ while (1) {
+ ubifs_search_zbranch(c, znode, key, &n);
+ if (n < 0) {
+ /*
+ * We reached a znode where the leftmost key is greater
+ * than the key we are searching for. This is the same
+ * situation as the one described in a huge comment at
+ * the end of the 'ubifs_lookup_level0()' function. And
+ * for exactly the same reasons we have to try to look
+ * left before giving up.
+ */
+ znode = left_znode(c, znode);
+ if (!znode)
+ return NULL;
+ if (IS_ERR(znode))
+ return znode;
+ ubifs_search_zbranch(c, znode, key, &n);
+ ubifs_assert(n >= 0);
+ }
+ if (znode->level == level + 1)
+ break;
+ znode = get_znode(c, znode, n);
+ if (IS_ERR(znode))
+ return znode;
+ }
+ /* Check if the child is the one we are looking for */
+ if (znode->zbranch[n].lnum == lnum && znode->zbranch[n].offs == offs)
+ return get_znode(c, znode, n);
+ /* If the key is unique, there is nowhere else to look */
+ if (!is_hash_key(c, key))
+ return NULL;
+ /*
+ * The key is not unique and so may be also in the znodes to either
+ * side.
+ */
+ zn = znode;
+ nn = n;
+ /* Look left */
+ while (1) {
+ /* Move one branch to the left */
+ if (n)
+ n -= 1;
+ else {
+ znode = left_znode(c, znode);
+ if (!znode)
+ break;
+ if (IS_ERR(znode))
+ return znode;
+ n = znode->child_cnt - 1;
+ }
+ /* Check it */
+ if (znode->zbranch[n].lnum == lnum &&
+ znode->zbranch[n].offs == offs)
+ return get_znode(c, znode, n);
+ /* Stop if the key is less than the one we are looking for */
+ if (keys_cmp(c, &znode->zbranch[n].key, key) < 0)
+ break;
+ }
+ /* Back to the middle */
+ znode = zn;
+ n = nn;
+ /* Look right */
+ while (1) {
+ /* Move one branch to the right */
+ if (++n >= znode->child_cnt) {
+ znode = right_znode(c, znode);
+ if (!znode)
+ break;
+ if (IS_ERR(znode))
+ return znode;
+ n = 0;
+ }
+ /* Check it */
+ if (znode->zbranch[n].lnum == lnum &&
+ znode->zbranch[n].offs == offs)
+ return get_znode(c, znode, n);
+ /* Stop if the key is greater than the one we are looking for */
+ if (keys_cmp(c, &znode->zbranch[n].key, key) > 0)
+ break;
+ }
+ return NULL;
+}
+
+/**
+ * is_idx_node_in_tnc - determine if an index node is in the TNC.
+ * @c: UBIFS file-system description object
+ * @key: key of index node
+ * @level: index node level
+ * @lnum: LEB number of index node
+ * @offs: offset of index node
+ *
+ * This function returns %0 if the index node is not referred to in the TNC, %1
+ * if the index node is referred to in the TNC and the corresponding znode is
+ * dirty, %2 if an index node is referred to in the TNC and the corresponding
+ * znode is clean, and a negative error code in case of failure.
+ *
+ * Note, the @key argument has to be the key of the first child. Also note,
+ * this function relies on the fact that 0:0 is never a valid LEB number and
+ * offset for a main-area node.
+ */
+int is_idx_node_in_tnc(struct ubifs_info *c, union ubifs_key *key, int level,
+ int lnum, int offs)
+{
+ struct ubifs_znode *znode;
+
+ znode = lookup_znode(c, key, level, lnum, offs);
+ if (!znode)
+ return 0;
+ if (IS_ERR(znode))
+ return PTR_ERR(znode);
+
+ return ubifs_zn_dirty(znode) ? 1 : 2;
+}
+
+/**
+ * is_leaf_node_in_tnc - determine if a non-indexing not is in the TNC.
+ * @c: UBIFS file-system description object
+ * @key: node key
+ * @lnum: node LEB number
+ * @offs: node offset
+ *
+ * This function returns %1 if the node is referred to in the TNC, %0 if it is
+ * not, and a negative error code in case of failure.
+ *
+ * Note, this function relies on the fact that 0:0 is never a valid LEB number
+ * and offset for a main-area node.
+ */
+static int is_leaf_node_in_tnc(struct ubifs_info *c, union ubifs_key *key,
+ int lnum, int offs)
+{
+ struct ubifs_zbranch *zbr;
+ struct ubifs_znode *znode, *zn;
+ int n, found, err, nn;
+ const int unique = !is_hash_key(c, key);
+
+ found = ubifs_lookup_level0(c, key, &znode, &n);
+ if (found < 0)
+ return found; /* Error code */
+ if (!found)
+ return 0;
+ zbr = &znode->zbranch[n];
+ if (lnum == zbr->lnum && offs == zbr->offs)
+ return 1; /* Found it */
+ if (unique)
+ return 0;
+ /*
+ * Because the key is not unique, we have to look left
+ * and right as well
+ */
+ zn = znode;
+ nn = n;
+ /* Look left */
+ while (1) {
+ err = tnc_prev(c, &znode, &n);
+ if (err == -ENOENT)
+ break;
+ if (err)
+ return err;
+ if (keys_cmp(c, key, &znode->zbranch[n].key))
+ break;
+ zbr = &znode->zbranch[n];
+ if (lnum == zbr->lnum && offs == zbr->offs)
+ return 1; /* Found it */
+ }
+ /* Look right */
+ znode = zn;
+ n = nn;
+ while (1) {
+ err = tnc_next(c, &znode, &n);
+ if (err) {
+ if (err == -ENOENT)
+ return 0;
+ return err;
+ }
+ if (keys_cmp(c, key, &znode->zbranch[n].key))
+ break;
+ zbr = &znode->zbranch[n];
+ if (lnum == zbr->lnum && offs == zbr->offs)
+ return 1; /* Found it */
+ }
+ return 0;
+}
+
+/**
+ * ubifs_tnc_has_node - determine whether a node is in the TNC.
+ * @c: UBIFS file-system description object
+ * @key: node key
+ * @level: index node level (if it is an index node)
+ * @lnum: node LEB number
+ * @offs: node offset
+ * @is_idx: non-zero if the node is an index node
+ *
+ * This function returns %1 if the node is in the TNC, %0 if it is not, and a
+ * negative error code in case of failure. For index nodes, @key has to be the
+ * key of the first child. An index node is considered to be in the TNC only if
+ * the corresponding znode is clean or has not been loaded.
+ */
+int ubifs_tnc_has_node(struct ubifs_info *c, union ubifs_key *key, int level,
+ int lnum, int offs, int is_idx)
+{
+ int err;
+
+ mutex_lock(&c->tnc_mutex);
+ if (is_idx) {
+ err = is_idx_node_in_tnc(c, key, level, lnum, offs);
+ if (err < 0)
+ goto out_unlock;
+ if (err == 1)
+ /* The index node was found but it was dirty */
+ err = 0;
+ else if (err == 2)
+ /* The index node was found and it was clean */
+ err = 1;
+ else
+ BUG_ON(err != 0);
+ } else
+ err = is_leaf_node_in_tnc(c, key, lnum, offs);
+
+out_unlock:
+ mutex_unlock(&c->tnc_mutex);
+ return err;
+}
+
+/**
+ * ubifs_dirty_idx_node - dirty an index node.
+ * @c: UBIFS file-system description object
+ * @key: index node key
+ * @level: index node level
+ * @lnum: index node LEB number
+ * @offs: index node offset
+ *
+ * This function loads and dirties an index node so that it can be garbage
+ * collected. The @key argument has to be the key of the first child. This
+ * function relies on the fact that 0:0 is never a valid LEB number and offset
+ * for a main-area node. Returns %0 on success and a negative error code on
+ * failure.
+ */
+int ubifs_dirty_idx_node(struct ubifs_info *c, union ubifs_key *key, int level,
+ int lnum, int offs)
+{
+ struct ubifs_znode *znode;
+ int err = 0;
+
+ mutex_lock(&c->tnc_mutex);
+ znode = lookup_znode(c, key, level, lnum, offs);
+ if (!znode)
+ goto out_unlock;
+ if (IS_ERR(znode)) {
+ err = PTR_ERR(znode);
+ goto out_unlock;
+ }
+ znode = dirty_cow_bottom_up(c, znode);
+ if (IS_ERR(znode)) {
+ err = PTR_ERR(znode);
+ goto out_unlock;
+ }
+
+out_unlock:
+ mutex_unlock(&c->tnc_mutex);
+ return err;
+}
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ * Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/* This file implements TNC functions for committing */
+
+#include "ubifs.h"
+
+/**
+ * make_idx_node - make an index node for fill-the-gaps method of TNC commit.
+ * @c: UBIFS file-system description object
+ * @idx: buffer in which to place new index node
+ * @znode: znode from which to make new index node
+ * @lnum: LEB number where new index node will be written
+ * @offs: offset where new index node will be written
+ * @len: length of new index node
+ */
+static int make_idx_node(struct ubifs_info *c, struct ubifs_idx_node *idx,
+ struct ubifs_znode *znode, int lnum, int offs, int len)
+{
+ struct ubifs_znode *zp;
+ int i, err;
+
+ /* Make index node */
+ idx->ch.node_type = UBIFS_IDX_NODE;
+ idx->child_cnt = cpu_to_le16(znode->child_cnt);
+ idx->level = cpu_to_le16(znode->level);
+ for (i = 0; i < znode->child_cnt; i++) {
+ struct ubifs_branch *br = ubifs_idx_branch(c, idx, i);
+ struct ubifs_zbranch *zbr = &znode->zbranch[i];
+
+ key_write_idx(c, &zbr->key, &br->key);
+ br->lnum = cpu_to_le32(zbr->lnum);
+ br->offs = cpu_to_le32(zbr->offs);
+ br->len = cpu_to_le32(zbr->len);
+ if (!zbr->lnum || !zbr->len) {
+ ubifs_err("bad ref in znode");
+ dbg_dump_znode(c, znode);
+ if (zbr->znode)
+ dbg_dump_znode(c, zbr->znode);
+ }
+ }
+ ubifs_prepare_node(c, idx, len, 0);
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+ znode->lnum = lnum;
+ znode->offs = offs;
+ znode->len = len;
+#endif
+
+ err = insert_old_idx_znode(c, znode);
+
+ /* Update the parent */
+ zp = znode->parent;
+ if (zp) {
+ struct ubifs_zbranch *zbr;
+
+ zbr = &zp->zbranch[znode->iip];
+ zbr->lnum = lnum;
+ zbr->offs = offs;
+ zbr->len = len;
+ } else {
+ c->zroot.lnum = lnum;
+ c->zroot.offs = offs;
+ c->zroot.len = len;
+ }
+ c->calc_idx_sz += ALIGN(len, 8);
+
+ atomic_long_dec(&c->dirty_zn_cnt);
+
+ ubifs_assert(ubifs_zn_dirty(znode));
+ ubifs_assert(test_bit(COW_ZNODE, &znode->flags));
+
+ __clear_bit(DIRTY_ZNODE, &znode->flags);
+ __clear_bit(COW_ZNODE, &znode->flags);
+
+ return err;
+}
+
+/**
+ * fill_gap - make index nodes in gaps in dirty index LEBs.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number that gap appears in
+ * @gap_start: offset of start of gap
+ * @gap_end: offset of end of gap
+ * @dirt: adds dirty space to this
+ *
+ * This function returns the number of index nodes written into the gap.
+ */
+static int fill_gap(struct ubifs_info *c, int lnum, int gap_start, int gap_end,
+ int *dirt)
+{
+ int len, gap_remains, gap_pos, written, pad_len;
+
+ ubifs_assert((gap_start & 7) == 0);
+ ubifs_assert((gap_end & 7) == 0);
+ ubifs_assert(gap_end >= gap_start);
+
+ gap_remains = gap_end - gap_start;
+ if (!gap_remains)
+ return 0;
+ gap_pos = gap_start;
+ written = 0;
+ while (c->enext) {
+ len = ubifs_idx_node_sz(c, c->enext->child_cnt);
+ if (len < gap_remains) {
+ struct ubifs_znode *znode = c->enext;
+ const int alen = ALIGN(len, 8);
+ int err;
+
+ ubifs_assert(alen <= gap_remains);
+ err = make_idx_node(c, c->ileb_buf + gap_pos, znode,
+ lnum, gap_pos, len);
+ if (err)
+ return err;
+ gap_remains -= alen;
+ gap_pos += alen;
+ c->enext = znode->cnext;
+ if (c->enext == c->cnext)
+ c->enext = NULL;
+ written += 1;
+ } else
+ break;
+ }
+ if (gap_end == c->leb_size) {
+ c->ileb_len = ALIGN(gap_pos, c->min_io_size);
+ /* Pad to end of min_io_size */
+ pad_len = c->ileb_len - gap_pos;
+ } else
+ /* Pad to end of gap */
+ pad_len = gap_remains;
+ dbg_gc("LEB %d:%d to %d len %d nodes written %d wasted bytes %d",
+ lnum, gap_start, gap_end, gap_end - gap_start, written, pad_len);
+ ubifs_pad(c, c->ileb_buf + gap_pos, pad_len);
+ *dirt += pad_len;
+ return written;
+}
+
+/**
+ * find_old_idx - find an index node obsoleted since the last commit start.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number of obsoleted index node
+ * @offs: offset of obsoleted index node
+ *
+ * Returns %1 if found and %0 otherwise.
+ */
+static int find_old_idx(struct ubifs_info *c, int lnum, int offs)
+{
+ struct ubifs_old_idx *o;
+ struct rb_node *p;
+
+ p = c->old_idx.rb_node;
+ while (p) {
+ o = rb_entry(p, struct ubifs_old_idx, rb);
+ if (lnum < o->lnum)
+ p = p->rb_left;
+ else if (lnum > o->lnum)
+ p = p->rb_right;
+ else if (offs < o->offs)
+ p = p->rb_left;
+ else if (offs > o->offs)
+ p = p->rb_right;
+ else
+ return 1;
+ }
+ return 0;
+}
+
+/**
+ * is_idx_node_in_use - determine if an index node can be overwritten.
+ * @c: UBIFS file-system description object
+ * @key: key of index node
+ * @level: index node level
+ * @lnum: LEB number of index node
+ * @offs: offset of index node
+ *
+ * If @key / @lnum / @offs identify an index node that was not part of the old
+ * index, then this function returns %0 (obsolete). Else if the index node was
+ * part of the old index but is now dirty %1 is returned, else if it is clean %2
+ * is returned. A negative error code is returned on failure.
+ */
+static int is_idx_node_in_use(struct ubifs_info *c, union ubifs_key *key,
+ int level, int lnum, int offs)
+{
+ int ret;
+
+ ret = is_idx_node_in_tnc(c, key, level, lnum, offs);
+ if (ret < 0)
+ return ret; /* Error code */
+ if (ret == 0)
+ if (find_old_idx(c, lnum, offs))
+ return 1;
+ return ret;
+}
+
+/**
+ * layout_leb_in_gaps - layout index nodes using in-the-gaps method.
+ * @c: UBIFS file-system description object
+ * @p: return LEB number here
+ *
+ * This function lays out new index nodes for dirty znodes using in-the-gaps
+ * method of TNC commit.
+ * This function merely puts the next znode into the next gap, making no attempt
+ * to try to maximise the number of znodes that fit.
+ * This function returns the number of index nodes written into the gaps, or a
+ * negative error code on failure.
+ */
+static int layout_leb_in_gaps(struct ubifs_info *c, int *p)
+{
+ struct ubifs_scan_leb *sleb;
+ struct ubifs_scan_node *snod;
+ int lnum, dirt = 0, gap_start, gap_end, err, written, tot_written;
+
+ tot_written = 0;
+ /* Get an index LEB with lots of obsolete index nodes */
+ lnum = ubifs_find_dirty_idx_leb(c);
+ if (lnum < 0)
+ /*
+ * There also may be dirt in the index head that could be
+ * filled, however we do not check there at present.
+ */
+ return lnum; /* Error code */
+ *p = lnum;
+ dbg_gc("LEB %d", lnum);
+ /*
+ * Scan the index LEB. We use the generic scan for this even though
+ * it is more comprehensive and less efficient than is needed for this
+ * purpose.
+ */
+ sleb = ubifs_scan(c, lnum, 0, c->ileb_buf);
+ c->ileb_len = 0;
+ if (IS_ERR(sleb))
+ return PTR_ERR(sleb);
+ gap_start = 0;
+ list_for_each_entry(snod, &sleb->nodes, list) {
+ struct ubifs_idx_node *idx;
+ int in_use, level;
+
+ ubifs_assert(snod->type == UBIFS_IDX_NODE);
+ idx = snod->node;
+ key_read(c, ubifs_idx_key(c, idx), &snod->key);
+ level = le16_to_cpu(idx->level);
+ /* Determine if the index node is in use (not obsolete) */
+ in_use = is_idx_node_in_use(c, &snod->key, level, lnum,
+ snod->offs);
+ if (in_use < 0) {
+ ubifs_scan_destroy(sleb);
+ return in_use; /* Error code */
+ }
+ if (in_use) {
+ if (in_use == 1)
+ dirt += ALIGN(snod->len, 8);
+ /*
+ * The obsolete index nodes form gaps that can be
+ * overwritten. This gap has ended because we have
+ * found an index node that is still in use
+ * i.e. not obsolete
+ */
+ gap_end = snod->offs;
+ /* Try to fill gap */
+ written = fill_gap(c, lnum, gap_start, gap_end, &dirt);
+ if (written < 0) {
+ ubifs_scan_destroy(sleb);
+ return written; /* Error code */
+ }
+ tot_written += written;
+ gap_start = ALIGN(snod->offs + snod->len, 8);
+ }
+ }
+ ubifs_scan_destroy(sleb);
+ c->ileb_len = c->leb_size;
+ gap_end = c->leb_size;
+ /* Try to fill gap */
+ written = fill_gap(c, lnum, gap_start, gap_end, &dirt);
+ if (written < 0)
+ return written; /* Error code */
+ tot_written += written;
+ if (tot_written == 0) {
+ struct ubifs_lprops lp;
+
+ dbg_gc("LEB %d wrote %d index nodes", lnum, tot_written);
+ err = ubifs_read_one_lp(c, lnum, &lp);
+ if (err)
+ return err;
+ if (lp.free == c->leb_size) {
+ /*
+ * We must have snatched this LEB from the idx_gc list
+ * so we need to correct the free and dirty space.
+ */
+ err = ubifs_change_one_lp(c, lnum,
+ c->leb_size - c->ileb_len,
+ dirt, 0, 0, 0);
+ if (err)
+ return err;
+ }
+ return 0;
+ }
+ err = ubifs_change_one_lp(c, lnum, c->leb_size - c->ileb_len, dirt,
+ 0, 0, 0);
+ if (err)
+ return err;
+ err = ubifs_leb_change(c, lnum, c->ileb_buf, c->ileb_len,
+ UBI_SHORTTERM);
+ if (err)
+ return err;
+ dbg_gc("LEB %d wrote %d index nodes", lnum, tot_written);
+ return tot_written;
+}
+
+/**
+ * get_leb_cnt - calculate the number of empty LEBs needed to commit.
+ * @c: UBIFS file-system description object
+ * @cnt: number of znodes to commit
+ *
+ * This function returns the number of empty LEBs needed to commit @cnt znodes
+ * to the current index head. The number is not exact and may be more than
+ * needed.
+ */
+static int get_leb_cnt(struct ubifs_info *c, int cnt)
+{
+ int d;
+
+ /* Assume maximum index node size (i.e. overestimate space needed) */
+ cnt -= (c->leb_size - c->ihead_offs) / c->max_idx_node_sz;
+ if (cnt < 0)
+ cnt = 0;
+ d = c->leb_size / c->max_idx_node_sz;
+ return DIV_ROUND_UP(cnt, d);
+}
+
+/**
+ * layout_in_gaps - in-the-gaps method of committing TNC.
+ * @c: UBIFS file-system description object
+ * @cnt: number of dirty znodes to commit.
+ *
+ * This function lays out new index nodes for dirty znodes using in-the-gaps
+ * method of TNC commit.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int layout_in_gaps(struct ubifs_info *c, int cnt)
+{
+ int err, leb_needed_cnt, written, *p;
+
+ dbg_gc("%d znodes to write", cnt);
+
+ c->gap_lebs = kmalloc(sizeof(int) * (c->lst.idx_lebs + 1), GFP_NOFS);
+ if (!c->gap_lebs)
+ return -ENOMEM;
+
+ p = c->gap_lebs;
+ do {
+ ubifs_assert(p < c->gap_lebs + sizeof(int) * c->lst.idx_lebs);
+ written = layout_leb_in_gaps(c, p);
+ if (written < 0) {
+ err = written;
+ if (err == -ENOSPC) {
+ if (!dbg_force_in_the_gaps_enabled) {
+ /*
+ * Do not print scary warnings if the
+ * debugging option which forces
+ * in-the-gaps is enabled.
+ */
+ ubifs_err("out of space");
+ spin_lock(&c->space_lock);
+ dbg_dump_budg(c);
+ spin_unlock(&c->space_lock);
+ dbg_dump_lprops(c);
+ }
+ /* Try to commit anyway */
+ err = 0;
+ break;
+ }
+ kfree(c->gap_lebs);
+ c->gap_lebs = NULL;
+ return err;
+ }
+ p++;
+ cnt -= written;
+ leb_needed_cnt = get_leb_cnt(c, cnt);
+ dbg_gc("%d znodes remaining, need %d LEBs, have %d", cnt,
+ leb_needed_cnt, c->ileb_cnt);
+ } while (leb_needed_cnt > c->ileb_cnt);
+
+ *p = -1;
+ return 0;
+}
+
+/**
+ * layout_in_empty_space - layout index nodes in empty space.
+ * @c: UBIFS file-system description object
+ *
+ * This function lays out new index nodes for dirty znodes using empty LEBs.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int layout_in_empty_space(struct ubifs_info *c)
+{
+ struct ubifs_znode *znode, *cnext, *zp;
+ int lnum, offs, len, next_len, buf_len, buf_offs, used, avail;
+ int wlen, blen, err;
+
+ cnext = c->enext;
+ if (!cnext)
+ return 0;
+
+ lnum = c->ihead_lnum;
+ buf_offs = c->ihead_offs;
+
+ buf_len = ubifs_idx_node_sz(c, c->fanout);
+ buf_len = ALIGN(buf_len, c->min_io_size);
+ used = 0;
+ avail = buf_len;
+
+ /* Ensure there is enough room for first write */
+ next_len = ubifs_idx_node_sz(c, cnext->child_cnt);
+ if (buf_offs + next_len > c->leb_size)
+ lnum = -1;
+
+ while (1) {
+ znode = cnext;
+
+ len = ubifs_idx_node_sz(c, znode->child_cnt);
+
+ /* Determine the index node position */
+ if (lnum == -1) {
+ if (c->ileb_nxt >= c->ileb_cnt) {
+ ubifs_err("out of space");
+ return -ENOSPC;
+ }
+ lnum = c->ilebs[c->ileb_nxt++];
+ buf_offs = 0;
+ used = 0;
+ avail = buf_len;
+ }
+
+ offs = buf_offs + used;
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+ znode->lnum = lnum;
+ znode->offs = offs;
+ znode->len = len;
+#endif
+
+ /* Update the parent */
+ zp = znode->parent;
+ if (zp) {
+ struct ubifs_zbranch *zbr;
+ int i;
+
+ i = znode->iip;
+ zbr = &zp->zbranch[i];
+ zbr->lnum = lnum;
+ zbr->offs = offs;
+ zbr->len = len;
+ } else {
+ c->zroot.lnum = lnum;
+ c->zroot.offs = offs;
+ c->zroot.len = len;
+ }
+ c->calc_idx_sz += ALIGN(len, 8);
+
+ /*
+ * Once lprops is updated, we can decrease the dirty znode count
+ * but it is easier to just do it here.
+ */
+ atomic_long_dec(&c->dirty_zn_cnt);
+
+ /*
+ * Calculate the next index node length to see if there is
+ * enough room for it
+ */
+ cnext = znode->cnext;
+ if (cnext == c->cnext)
+ next_len = 0;
+ else
+ next_len = ubifs_idx_node_sz(c, cnext->child_cnt);
+
+ if (c->min_io_size == 1) {
+ buf_offs += ALIGN(len, 8);
+ if (next_len) {
+ if (buf_offs + next_len <= c->leb_size)
+ continue;
+ err = ubifs_update_one_lp(c, lnum, 0,
+ c->leb_size - buf_offs, 0, 0);
+ if (err)
+ return err;
+ lnum = -1;
+ continue;
+ }
+ err = ubifs_update_one_lp(c, lnum,
+ c->leb_size - buf_offs, 0, 0, 0);
+ if (err)
+ return err;
+ break;
+ }
+
+ /* Update buffer positions */
+ wlen = used + len;
+ used += ALIGN(len, 8);
+ avail -= ALIGN(len, 8);
+
+ if (next_len != 0 &&
+ buf_offs + used + next_len <= c->leb_size &&
+ avail > 0)
+ continue;
+
+ if (avail <= 0 && next_len &&
+ buf_offs + used + next_len <= c->leb_size)
+ blen = buf_len;
+ else
+ blen = ALIGN(wlen, c->min_io_size);
+
+ /* The buffer is full or there are no more znodes to do */
+ buf_offs += blen;
+ if (next_len) {
+ if (buf_offs + next_len > c->leb_size) {
+ err = ubifs_update_one_lp(c, lnum,
+ c->leb_size - buf_offs, blen - used,
+ 0, 0);
+ if (err)
+ return err;
+ lnum = -1;
+ }
+ used -= blen;
+ if (used < 0)
+ used = 0;
+ avail = buf_len - used;
+ continue;
+ }
+ err = ubifs_update_one_lp(c, lnum, c->leb_size - buf_offs,
+ blen - used, 0, 0);
+ if (err)
+ return err;
+ break;
+ }
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+ c->new_ihead_lnum = lnum;
+ c->new_ihead_offs = buf_offs;
+#endif
+
+ return 0;
+}
+
+/**
+ * layout_commit - determine positions of index nodes to commit.
+ * @c: UBIFS file-system description object
+ * @no_space: indicates that insufficient empty LEBs were allocated
+ * @cnt: number of znodes to commit
+ *
+ * Calculate and update the positions of index nodes to commit. If there were
+ * an insufficient number of empty LEBs allocated, then index nodes are placed
+ * into the gaps created by obsolete index nodes in non-empty index LEBs. For
+ * this purpose, an obsolete index node is one that was not in the index as at
+ * the end of the last commit. To write "in-the-gaps" requires that those index
+ * LEBs are updated atomically in-place.
+ */
+static int layout_commit(struct ubifs_info *c, int no_space, int cnt)
+{
+ int err;
+
+ if (no_space) {
+ err = layout_in_gaps(c, cnt);
+ if (err)
+ return err;
+ }
+ err = layout_in_empty_space(c);
+ return err;
+}
+
+/**
+ * find_first_dirty - find first dirty znode.
+ * @znode: znode to begin searching from
+ */
+static struct ubifs_znode *find_first_dirty(struct ubifs_znode *znode)
+{
+ int i, cont;
+
+ if (!znode)
+ return NULL;
+
+ while (1) {
+ if (znode->level == 0) {
+ if (ubifs_zn_dirty(znode))
+ return znode;
+ return NULL;
+ }
+ cont = 0;
+ for (i = 0; i < znode->child_cnt; i++) {
+ struct ubifs_zbranch *zbr = &znode->zbranch[i];
+
+ if (zbr->znode && ubifs_zn_dirty(zbr->znode)) {
+ znode = zbr->znode;
+ cont = 1;
+ break;
+ }
+ }
+ if (!cont) {
+ if (ubifs_zn_dirty(znode))
+ return znode;
+ return NULL;
+ }
+ }
+}
+
+/**
+ * find_next_dirty - find next dirty znode.
+ * @znode: znode to begin searching from
+ */
+static struct ubifs_znode *find_next_dirty(struct ubifs_znode *znode)
+{
+ int n = znode->iip + 1;
+
+ znode = znode->parent;
+ if (!znode)
+ return NULL;
+ for (; n < znode->child_cnt; n++) {
+ struct ubifs_zbranch *zbr = &znode->zbranch[n];
+
+ if (zbr->znode && ubifs_zn_dirty(zbr->znode))
+ return find_first_dirty(zbr->znode);
+ }
+ return znode;
+}
+
+/**
+ * get_znodes_to_commit - create list of dirty znodes to commit.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns the number of znodes to commit.
+ */
+static int get_znodes_to_commit(struct ubifs_info *c)
+{
+ struct ubifs_znode *znode, *cnext;
+ int cnt = 0;
+
+ c->cnext = find_first_dirty(c->zroot.znode);
+ znode = c->enext = c->cnext;
+ if (!znode) {
+ dbg_cmt("no znodes to commit");
+ return 0;
+ }
+ cnt += 1;
+ while (1) {
+ ubifs_assert(!test_bit(COW_ZNODE, &znode->flags));
+ __set_bit(COW_ZNODE, &znode->flags);
+ znode->alt = 0;
+ cnext = find_next_dirty(znode);
+ if (!cnext) {
+ znode->cnext = c->cnext;
+ break;
+ }
+ znode->cnext = cnext;
+ znode = cnext;
+ cnt += 1;
+ }
+ dbg_cmt("committing %d znodes", cnt);
+ ubifs_assert(cnt == atomic_long_read(&c->dirty_zn_cnt));
+ return cnt;
+}
+
+/**
+ * alloc_idx_lebs - allocate empty LEBs to be used to commit.
+ * @c: UBIFS file-system description object
+ * @cnt: number of znodes to commit
+ *
+ * This function returns %-ENOSPC if it cannot allocate a sufficient number of
+ * empty LEBs. %0 is returned on success, otherwise a negative error code
+ * is returned.
+ */
+static int alloc_idx_lebs(struct ubifs_info *c, int cnt)
+{
+ int i, leb_cnt, lnum;
+
+ c->ileb_cnt = 0;
+ c->ileb_nxt = 0;
+ leb_cnt = get_leb_cnt(c, cnt);
+ dbg_cmt("need about %d empty LEBS for TNC commit", leb_cnt);
+ if (!leb_cnt)
+ return 0;
+ c->ilebs = kmalloc(leb_cnt * sizeof(int), GFP_NOFS);
+ if (!c->ilebs)
+ return -ENOMEM;
+ for (i = 0; i < leb_cnt; i++) {
+ lnum = ubifs_find_free_leb_for_idx(c);
+ if (lnum < 0)
+ return lnum;
+ c->ilebs[c->ileb_cnt++] = lnum;
+ dbg_cmt("LEB %d", lnum);
+ }
+ if (dbg_force_in_the_gaps())
+ return -ENOSPC;
+ return 0;
+}
+
+/**
+ * free_unused_idx_lebs - free unused LEBs that were allocated for the commit.
+ * @c: UBIFS file-system description object
+ *
+ * It is possible that we allocate more empty LEBs for the commit than we need.
+ * This functions frees the surplus.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int free_unused_idx_lebs(struct ubifs_info *c)
+{
+ int i, err = 0, lnum, er;
+
+ for (i = c->ileb_nxt; i < c->ileb_cnt; i++) {
+ lnum = c->ilebs[i];
+ dbg_cmt("LEB %d", lnum);
+ er = ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0,
+ LPROPS_INDEX | LPROPS_TAKEN, 0);
+ if (!err)
+ err = er;
+ }
+ return err;
+}
+
+/**
+ * free_idx_lebs - free unused LEBs after commit end.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int free_idx_lebs(struct ubifs_info *c)
+{
+ int err;
+
+ err = free_unused_idx_lebs(c);
+ kfree(c->ilebs);
+ c->ilebs = NULL;
+ return err;
+}
+
+/**
+ * ubifs_tnc_start_commit - start TNC commit.
+ * @c: UBIFS file-system description object
+ * @zroot: new index root position is returned here
+ *
+ * This function prepares the list of indexing nodes to commit and lays out
+ * their positions on flash. If there is not enough free space it uses the
+ * in-gap commit method. Returns zero in case of success and a negative error
+ * code in case of failure.
+ */
+int ubifs_tnc_start_commit(struct ubifs_info *c, struct ubifs_zbranch *zroot)
+{
+ int err = 0, cnt;
+
+ mutex_lock(&c->tnc_mutex);
+ err = dbg_check_tnc(c, 1);
+ if (err)
+ goto out;
+ cnt = get_znodes_to_commit(c);
+ if (cnt != 0) {
+ int no_space = 0;
+
+ err = alloc_idx_lebs(c, cnt);
+ if (err == -ENOSPC)
+ no_space = 1;
+ else if (err)
+ goto out_free;
+ err = layout_commit(c, no_space, cnt);
+ if (err)
+ goto out_free;
+ ubifs_assert(atomic_long_read(&c->dirty_zn_cnt) == 0);
+ err = free_unused_idx_lebs(c);
+ if (err)
+ goto out;
+ }
+ destroy_old_idx(c);
+ memcpy(zroot, &c->zroot, sizeof(struct ubifs_zbranch));
+
+ err = ubifs_save_dirty_idx_lnums(c);
+ if (err)
+ goto out;
+
+ spin_lock(&c->space_lock);
+ /*
+ * Although we have not finished committing yet, update size of the
+ * committed index ('c->old_idx_sz') and zero out the index growth
+ * budget. It is OK to do this now, because we've reserved all the
+ * space which is needed to commit the index, and it is save for the
+ * budgeting subsystem to assume the index is already committed,
+ * even though it is not.
+ */
+ c->old_idx_sz = c->calc_idx_sz;
+ c->budg_uncommitted_idx = 0;
+ spin_unlock(&c->space_lock);
+ mutex_unlock(&c->tnc_mutex);
+
+ dbg_cmt("number of index LEBs %d", c->lst.idx_lebs);
+ dbg_cmt("size of index %llu", c->calc_idx_sz);
+ return err;
+
+out_free:
+ free_idx_lebs(c);
+out:
+ mutex_unlock(&c->tnc_mutex);
+ return err;
+}
+
+/**
+ * write_index - write index nodes.
+ * @c: UBIFS file-system description object
+ *
+ * This function writes the index nodes whose positions were laid out in the
+ * layout_in_empty_space function.
+ */
+static int write_index(struct ubifs_info *c)
+{
+ struct ubifs_idx_node *idx;
+ struct ubifs_znode *znode, *cnext;
+ int i, lnum, offs, len, next_len, buf_len, buf_offs, used;
+ int avail, wlen, err, lnum_pos = 0;
+
+ cnext = c->enext;
+ if (!cnext)
+ return 0;
+
+ /*
+ * Always write index nodes to the index head so that index nodes and
+ * other types of nodes are never mixed in the same erase block.
+ */
+ lnum = c->ihead_lnum;
+ buf_offs = c->ihead_offs;
+
+ /* Allocate commit buffer */
+ buf_len = ALIGN(c->max_idx_node_sz, c->min_io_size);
+ used = 0;
+ avail = buf_len;
+
+ /* Ensure there is enough room for first write */
+ next_len = ubifs_idx_node_sz(c, cnext->child_cnt);
+ if (buf_offs + next_len > c->leb_size) {
+ err = ubifs_update_one_lp(c, lnum, LPROPS_NC, 0, 0,
+ LPROPS_TAKEN);
+ if (err)
+ return err;
+ lnum = -1;
+ }
+
+ while (1) {
+ cond_resched();
+
+ znode = cnext;
+ idx = c->cbuf + used;
+
+ /* Make index node */
+ idx->ch.node_type = UBIFS_IDX_NODE;
+ idx->child_cnt = cpu_to_le16(znode->child_cnt);
+ idx->level = cpu_to_le16(znode->level);
+ for (i = 0; i < znode->child_cnt; i++) {
+ struct ubifs_branch *br = ubifs_idx_branch(c, idx, i);
+ struct ubifs_zbranch *zbr = &znode->zbranch[i];
+
+ key_write_idx(c, &zbr->key, &br->key);
+ br->lnum = cpu_to_le32(zbr->lnum);
+ br->offs = cpu_to_le32(zbr->offs);
+ br->len = cpu_to_le32(zbr->len);
+ if (!zbr->lnum || !zbr->len) {
+ ubifs_err("bad ref in znode");
+ dbg_dump_znode(c, znode);
+ if (zbr->znode)
+ dbg_dump_znode(c, zbr->znode);
+ }
+ }
+ len = ubifs_idx_node_sz(c, znode->child_cnt);
+ ubifs_prepare_node(c, idx, len, 0);
+
+ /* Determine the index node position */
+ if (lnum == -1) {
+ lnum = c->ilebs[lnum_pos++];
+ buf_offs = 0;
+ used = 0;
+ avail = buf_len;
+ }
+ offs = buf_offs + used;
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+ if (lnum != znode->lnum || offs != znode->offs ||
+ len != znode->len) {
+ ubifs_err("inconsistent znode posn");
+ return -EINVAL;
+ }
+#endif
+
+ /* Grab some stuff from znode while we still can */
+ cnext = znode->cnext;
+
+ ubifs_assert(ubifs_zn_dirty(znode));
+ ubifs_assert(test_bit(COW_ZNODE, &znode->flags));
+
+ /*
+ * It is important that other threads should see %DIRTY_ZNODE
+ * flag cleared before %COW_ZNODE. Specifically, it matters in
+ * the 'dirty_cow_znode()' function. This is the reason for the
+ * first barrier. Also, we want the bit changes to be seen to
+ * other threads ASAP, to avoid unnecesarry copying, which is
+ * the reason for the second barrier.
+ */
+ clear_bit(DIRTY_ZNODE, &znode->flags);
+ smp_mb__before_clear_bit();
+ clear_bit(COW_ZNODE, &znode->flags);
+ smp_mb__after_clear_bit();
+
+ /* Do not access znode from this point on */
+
+ /* Update buffer positions */
+ wlen = used + len;
+ used += ALIGN(len, 8);
+ avail -= ALIGN(len, 8);
+
+ /*
+ * Calculate the next index node length to see if there is
+ * enough room for it
+ */
+ if (cnext == c->cnext)
+ next_len = 0;
+ else
+ next_len = ubifs_idx_node_sz(c, cnext->child_cnt);
+
+ if (c->min_io_size == 1) {
+ /*
+ * Write the prepared index node immediately if there is
+ * no minimum IO size
+ */
+ err = ubifs_leb_write(c, lnum, c->cbuf, buf_offs,
+ wlen, UBI_SHORTTERM);
+ if (err)
+ return err;
+ buf_offs += ALIGN(wlen, 8);
+ if (next_len) {
+ used = 0;
+ avail = buf_len;
+ if (buf_offs + next_len > c->leb_size) {
+ err = ubifs_update_one_lp(c, lnum,
+ LPROPS_NC, 0, 0, LPROPS_TAKEN);
+ if (err)
+ return err;
+ lnum = -1;
+ }
+ continue;
+ }
+ } else {
+ int blen, nxt_offs = buf_offs + used + next_len;
+
+ if (next_len && nxt_offs <= c->leb_size) {
+ if (avail > 0)
+ continue;
+ else
+ blen = buf_len;
+ } else {
+ wlen = ALIGN(wlen, 8);
+ blen = ALIGN(wlen, c->min_io_size);
+ ubifs_pad(c, c->cbuf + wlen, blen - wlen);
+ }
+ /*
+ * The buffer is full or there are no more znodes
+ * to do
+ */
+ err = ubifs_leb_write(c, lnum, c->cbuf, buf_offs,
+ blen, UBI_SHORTTERM);
+ if (err)
+ return err;
+ buf_offs += blen;
+ if (next_len) {
+ if (nxt_offs > c->leb_size) {
+ err = ubifs_update_one_lp(c, lnum,
+ LPROPS_NC, 0, 0, LPROPS_TAKEN);
+ if (err)
+ return err;
+ lnum = -1;
+ }
+ used -= blen;
+ if (used < 0)
+ used = 0;
+ avail = buf_len - used;
+ memmove(c->cbuf, c->cbuf + blen, used);
+ continue;
+ }
+ }
+ break;
+ }
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+ if (lnum != c->new_ihead_lnum || buf_offs != c->new_ihead_offs) {
+ ubifs_err("inconsistent ihead");
+ return -EINVAL;
+ }
+#endif
+
+ c->ihead_lnum = lnum;
+ c->ihead_offs = buf_offs;
+
+ return 0;
+}
+
+/**
+ * free_obsolete_znodes - free obsolete znodes.
+ * @c: UBIFS file-system description object
+ *
+ * At the end of commit end, obsolete znodes are freed.
+ */
+static void free_obsolete_znodes(struct ubifs_info *c)
+{
+ struct ubifs_znode *znode, *cnext;
+
+ cnext = c->cnext;
+ do {
+ znode = cnext;
+ cnext = znode->cnext;
+ if (test_bit(OBSOLETE_ZNODE, &znode->flags))
+ kfree(znode);
+ else {
+ znode->cnext = NULL;
+ atomic_long_inc(&c->clean_zn_cnt);
+ atomic_long_inc(&ubifs_clean_zn_cnt);
+ }
+ } while (cnext != c->cnext);
+}
+
+/**
+ * return_gap_lebs - return LEBs used by the in-gap commit method.
+ * @c: UBIFS file-system description object
+ *
+ * This function clears the "taken" flag for the LEBs which were used by the
+ * "commit in-the-gaps" method.
+ */
+static int return_gap_lebs(struct ubifs_info *c)
+{
+ int *p, err;
+
+ if (!c->gap_lebs)
+ return 0;
+
+ dbg_cmt("");
+ for (p = c->gap_lebs; *p != -1; p++) {
+ err = ubifs_change_one_lp(c, *p, LPROPS_NC, LPROPS_NC, 0,
+ LPROPS_TAKEN, 0);
+ if (err)
+ return err;
+ }
+
+ kfree(c->gap_lebs);
+ c->gap_lebs = NULL;
+ return 0;
+}
+
+/**
+ * ubifs_tnc_end_commit - update the TNC for commit end.
+ * @c: UBIFS file-system description object
+ *
+ * Write the dirty znodes.
+ */
+int ubifs_tnc_end_commit(struct ubifs_info *c)
+{
+ int err;
+
+ if (!c->cnext)
+ return 0;
+
+ err = return_gap_lebs(c);
+ if (err)
+ return err;
+
+ err = write_index(c);
+ if (err)
+ return err;
+
+ mutex_lock(&c->tnc_mutex);
+
+ dbg_cmt("TNC height is %d", c->zroot.znode->level + 1);
+
+ free_obsolete_znodes(c);
+
+ c->cnext = NULL;
+ kfree(c->ilebs);
+ c->ilebs = NULL;
+
+ mutex_unlock(&c->tnc_mutex);
+
+ return 0;
+}
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Adrian Hunter
+ * Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file contains miscelanious TNC-related functions shared betweend
+ * different files. This file does not form any logically separate TNC
+ * sub-system. The file was created because there is a lot of TNC code and
+ * putting it all in one file would make that file too big and unreadable.
+ */
+
+#include "ubifs.h"
+
+/**
+ * ubifs_tnc_levelorder_next - next TNC tree element in levelorder traversal.
+ * @zr: root of the subtree to traverse
+ * @znode: previous znode
+ *
+ * This function implements levelorder TNC traversal. The LNC is ignored.
+ * Returns the next element or %NULL if @znode is already the last one.
+ */
+struct ubifs_znode *ubifs_tnc_levelorder_next(struct ubifs_znode *zr,
+ struct ubifs_znode *znode)
+{
+ int level, iip, level_search = 0;
+ struct ubifs_znode *zn;
+
+ ubifs_assert(zr);
+
+ if (unlikely(!znode))
+ return zr;
+
+ if (unlikely(znode == zr)) {
+ if (znode->level == 0)
+ return NULL;
+ return ubifs_tnc_find_child(zr, 0);
+ }
+
+ level = znode->level;
+
+ iip = znode->iip;
+ while (1) {
+ ubifs_assert(znode->level <= zr->level);
+
+ /*
+ * First walk up until there is a znode with next branch to
+ * look at.
+ */
+ while (znode->parent != zr && iip >= znode->parent->child_cnt) {
+ znode = znode->parent;
+ iip = znode->iip;
+ }
+
+ if (unlikely(znode->parent == zr &&
+ iip >= znode->parent->child_cnt)) {
+ /* This level is done, switch to the lower one */
+ level -= 1;
+ if (level_search || level < 0)
+ /*
+ * We were already looking for znode at lower
+ * level ('level_search'). As we are here
+ * again, it just does not exist. Or all levels
+ * were finished ('level < 0').
+ */
+ return NULL;
+
+ level_search = 1;
+ iip = -1;
+ znode = ubifs_tnc_find_child(zr, 0);
+ ubifs_assert(znode);
+ }
+
+ /* Switch to the next index */
+ zn = ubifs_tnc_find_child(znode->parent, iip + 1);
+ if (!zn) {
+ /* No more children to look at, we have walk up */
+ iip = znode->parent->child_cnt;
+ continue;
+ }
+
+ /* Walk back down to the level we came from ('level') */
+ while (zn->level != level) {
+ znode = zn;
+ zn = ubifs_tnc_find_child(zn, 0);
+ if (!zn) {
+ /*
+ * This path is not too deep so it does not
+ * reach 'level'. Try next path.
+ */
+ iip = znode->iip;
+ break;
+ }
+ }
+
+ if (zn) {
+ ubifs_assert(zn->level >= 0);
+ return zn;
+ }
+ }
+}
+
+/**
+ * ubifs_search_zbranch - search znode branch.
+ * @c: UBIFS file-system description object
+ * @znode: znode to search in
+ * @key: key to search for
+ * @n: znode branch slot number is returned here
+ *
+ * This is a helper function which search branch with key @key in @znode using
+ * binary search. The result of the search may be:
+ * o exact match, then %1 is returned, and the slot number of the branch is
+ * stored in @n;
+ * o no exact match, then %0 is returned and the slot number of the left
+ * closest branch is returned in @n; the slot if all keys in this znode are
+ * greater than @key, then %-1 is returned in @n.
+ */
+int ubifs_search_zbranch(const struct ubifs_info *c,
+ const struct ubifs_znode *znode,
+ const union ubifs_key *key, int *n)
+{
+ int beg = 0, end = znode->child_cnt, uninitialized_var(mid);
+ int uninitialized_var(cmp);
+ const struct ubifs_zbranch *zbr = &znode->zbranch[0];
+
+ ubifs_assert(end > beg);
+
+ while (end > beg) {
+ mid = (beg + end) >> 1;
+ cmp = keys_cmp(c, key, &zbr[mid].key);
+ if (cmp > 0)
+ beg = mid + 1;
+ else if (cmp < 0)
+ end = mid;
+ else {
+ *n = mid;
+ return 1;
+ }
+ }
+
+ *n = end - 1;
+
+ /* The insert point is after *n */
+ ubifs_assert(*n >= -1 && *n < znode->child_cnt);
+ if (*n == -1)
+ ubifs_assert(keys_cmp(c, key, &zbr[0].key) < 0);
+ else
+ ubifs_assert(keys_cmp(c, key, &zbr[*n].key) > 0);
+ if (*n + 1 < znode->child_cnt)
+ ubifs_assert(keys_cmp(c, key, &zbr[*n + 1].key) < 0);
+
+ return 0;
+}
+
+/**
+ * ubifs_tnc_postorder_first - find first znode to do postorder tree traversal.
+ * @znode: znode to start at (root of the sub-tree to traverse)
+ *
+ * Find the lowest leftmost znode in a subtree of the TNC tree. The LNC is
+ * ignored.
+ */
+struct ubifs_znode *ubifs_tnc_postorder_first(struct ubifs_znode *znode)
+{
+ if (unlikely(!znode))
+ return NULL;
+
+ while (znode->level > 0) {
+ struct ubifs_znode *child;
+
+ child = ubifs_tnc_find_child(znode, 0);
+ if (!child)
+ return znode;
+ znode = child;
+ }
+
+ return znode;
+}
+
+/**
+ * ubifs_tnc_postorder_next - next TNC tree element in postorder traversal.
+ * @znode: previous znode
+ *
+ * This function implements postorder TNC traversal. The LNC is ignored.
+ * Returns the next element or %NULL if @znode is already the last one.
+ */
+struct ubifs_znode *ubifs_tnc_postorder_next(struct ubifs_znode *znode)
+{
+ struct ubifs_znode *zn;
+
+ ubifs_assert(znode);
+ if (unlikely(!znode->parent))
+ return NULL;
+
+ /* Switch to the next index in the parent */
+ zn = ubifs_tnc_find_child(znode->parent, znode->iip + 1);
+ if (!zn)
+ /* This is in fact the last child, return parent */
+ return znode->parent;
+
+ /* Go to the first znode in this new subtree */
+ return ubifs_tnc_postorder_first(zn);
+}
+
+/**
+ * ubifs_destroy_tnc_subtree - destroy all znodes connected to a subtree.
+ * @znode: znode defining subtree to destroy
+ *
+ * This function destroys subtree of the TNC tree. Returns number of clean
+ * znodes in the subtree.
+ */
+long ubifs_destroy_tnc_subtree(struct ubifs_znode *znode)
+{
+ struct ubifs_znode *zn = ubifs_tnc_postorder_first(znode);
+ long clean_freed = 0;
+ int n;
+
+ ubifs_assert(zn);
+ while (1) {
+ for (n = 0; n < zn->child_cnt; n++) {
+ if (!zn->zbranch[n].znode)
+ continue;
+
+ if (zn->level > 0 &&
+ !ubifs_zn_dirty(zn->zbranch[n].znode))
+ clean_freed += 1;
+
+ cond_resched();
+ kfree(zn->zbranch[n].znode);
+ }
+
+ if (zn == znode) {
+ if (!ubifs_zn_dirty(zn))
+ clean_freed += 1;
+ kfree(zn);
+ return clean_freed;
+ }
+
+ zn = ubifs_tnc_postorder_next(zn);
+ }
+}
+
+/**
+ * read_znode - read an indexing node from flash and fill znode.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB of the indexing node to read
+ * @offs: node offset
+ * @len: node length
+ * @znode: znode to read to
+ *
+ * This function reads an indexing node from the flash media and fills znode
+ * with the read data. Returns zero in case of success and a negative error
+ * code in case of failure. The read indexing node is validated and if anything
+ * is wrong with it, this function prints complaint messages and returns
+ * %-EINVAL.
+ */
+static int read_znode(struct ubifs_info *c, int lnum, int offs, int len,
+ struct ubifs_znode *znode)
+{
+ int i, err, type, cmp;
+ struct ubifs_idx_node *idx;
+
+ idx = kmalloc(c->max_idx_node_sz, GFP_NOFS);
+ if (!idx)
+ return -ENOMEM;
+
+ err = ubifs_read_node(c, idx, UBIFS_IDX_NODE, len, lnum, offs);
+ if (err < 0) {
+ kfree(idx);
+ return err;
+ }
+
+ znode->child_cnt = le16_to_cpu(idx->child_cnt);
+ znode->level = le16_to_cpu(idx->level);
+
+ dbg_tnc("LEB %d:%d, level %d, %d branch",
+ lnum, offs, znode->level, znode->child_cnt);
+
+ if (znode->child_cnt > c->fanout || znode->level > UBIFS_MAX_LEVELS) {
+ dbg_err("current fanout %d, branch count %d",
+ c->fanout, znode->child_cnt);
+ dbg_err("max levels %d, znode level %d",
+ UBIFS_MAX_LEVELS, znode->level);
+ err = 1;
+ goto out_dump;
+ }
+
+ for (i = 0; i < znode->child_cnt; i++) {
+ const struct ubifs_branch *br = ubifs_idx_branch(c, idx, i);
+ struct ubifs_zbranch *zbr = &znode->zbranch[i];
+
+ key_read(c, &br->key, &zbr->key);
+ zbr->lnum = le32_to_cpu(br->lnum);
+ zbr->offs = le32_to_cpu(br->offs);
+ zbr->len = le32_to_cpu(br->len);
+ zbr->znode = NULL;
+
+ /* Validate branch */
+
+ if (zbr->lnum < c->main_first ||
+ zbr->lnum >= c->leb_cnt || zbr->offs < 0 ||
+ zbr->offs + zbr->len > c->leb_size || zbr->offs & 7) {
+ dbg_err("bad branch %d", i);
+ err = 2;
+ goto out_dump;
+ }
+
+ switch (key_type(c, &zbr->key)) {
+ case UBIFS_INO_KEY:
+ case UBIFS_DATA_KEY:
+ case UBIFS_DENT_KEY:
+ case UBIFS_XENT_KEY:
+ break;
+ default:
+ dbg_msg("bad key type at slot %d: %s", i,
+ DBGKEY(&zbr->key));
+ err = 3;
+ goto out_dump;
+ }
+
+ if (znode->level)
+ continue;
+
+ type = key_type(c, &zbr->key);
+ if (c->ranges[type].max_len == 0) {
+ if (zbr->len != c->ranges[type].len) {
+ dbg_err("bad target node (type %d) length (%d)",
+ type, zbr->len);
+ dbg_err("have to be %d", c->ranges[type].len);
+ err = 4;
+ goto out_dump;
+ }
+ } else if (zbr->len < c->ranges[type].min_len ||
+ zbr->len > c->ranges[type].max_len) {
+ dbg_err("bad target node (type %d) length (%d)",
+ type, zbr->len);
+ dbg_err("have to be in range of %d-%d",
+ c->ranges[type].min_len,
+ c->ranges[type].max_len);
+ err = 5;
+ goto out_dump;
+ }
+ }
+
+ /*
+ * Ensure that the next key is greater or equivalent to the
+ * previous one.
+ */
+ for (i = 0; i < znode->child_cnt - 1; i++) {
+ const union ubifs_key *key1, *key2;
+
+ key1 = &znode->zbranch[i].key;
+ key2 = &znode->zbranch[i + 1].key;
+
+ cmp = keys_cmp(c, key1, key2);
+ if (cmp > 0) {
+ dbg_err("bad key order (keys %d and %d)", i, i + 1);
+ err = 6;
+ goto out_dump;
+ } else if (cmp == 0 && !is_hash_key(c, key1)) {
+ /* These can only be keys with colliding hash */
+ dbg_err("keys %d and %d are not hashed but equivalent",
+ i, i + 1);
+ err = 7;
+ goto out_dump;
+ }
+ }
+
+ kfree(idx);
+ return 0;
+
+out_dump:
+ ubifs_err("bad indexing node at LEB %d:%d, error %d", lnum, offs, err);
+ dbg_dump_node(c, idx);
+ kfree(idx);
+ return -EINVAL;
+}
+
+/**
+ * ubifs_load_znode - load znode to TNC cache.
+ * @c: UBIFS file-system description object
+ * @zbr: znode branch
+ * @parent: znode's parent
+ * @iip: index in parent
+ *
+ * This function loads znode pointed to by @zbr into the TNC cache and
+ * returns pointer to it in case of success and a negative error code in case
+ * of failure.
+ */
+struct ubifs_znode *ubifs_load_znode(struct ubifs_info *c,
+ struct ubifs_zbranch *zbr,
+ struct ubifs_znode *parent, int iip)
+{
+ int err;
+ struct ubifs_znode *znode;
+
+ ubifs_assert(!zbr->znode);
+ /*
+ * A slab cache is not presently used for znodes because the znode size
+ * depends on the fanout which is stored in the superblock.
+ */
+ znode = kzalloc(c->max_znode_sz, GFP_NOFS);
+ if (!znode)
+ return ERR_PTR(-ENOMEM);
+
+ err = read_znode(c, zbr->lnum, zbr->offs, zbr->len, znode);
+ if (err)
+ goto out;
+
+ atomic_long_inc(&c->clean_zn_cnt);
+
+ /*
+ * Increment the global clean znode counter as well. It is OK that
+ * global and per-FS clean znode counters may be inconsistent for some
+ * short time (because we might be preempted at this point), the global
+ * one is only used in shrinker.
+ */
+ atomic_long_inc(&ubifs_clean_zn_cnt);
+
+ zbr->znode = znode;
+ znode->parent = parent;
+ znode->time = get_seconds();
+ znode->iip = iip;
+
+ return znode;
+
+out:
+ kfree(znode);
+ return ERR_PTR(err);
+}
+
+/**
+ * ubifs_tnc_read_node - read a leaf node from the flash media.
+ * @c: UBIFS file-system description object
+ * @zbr: key and position of the node
+ * @node: node is returned here
+ *
+ * This function reads a node defined by @zbr from the flash media. Returns
+ * zero in case of success or a negative negative error code in case of
+ * failure.
+ */
+int ubifs_tnc_read_node(struct ubifs_info *c, struct ubifs_zbranch *zbr,
+ void *node)
+{
+ union ubifs_key key1, *key = &zbr->key;
+ int err, type = key_type(c, key);
+ struct ubifs_wbuf *wbuf;
+
+ /*
+ * 'zbr' has to point to on-flash node. The node may sit in a bud and
+ * may even be in a write buffer, so we have to take care about this.
+ */
+ wbuf = ubifs_get_wbuf(c, zbr->lnum);
+ if (wbuf)
+ err = ubifs_read_node_wbuf(wbuf, node, type, zbr->len,
+ zbr->lnum, zbr->offs);
+ else
+ err = ubifs_read_node(c, node, type, zbr->len, zbr->lnum,
+ zbr->offs);
+
+ if (err) {
+ dbg_tnc("key %s", DBGKEY(key));
+ return err;
+ }
+
+ /* Make sure the key of the read node is correct */
+ key_read(c, key, &key1);
+ if (memcmp(node + UBIFS_KEY_OFFSET, &key1, c->key_len)) {
+ ubifs_err("bad key in node at LEB %d:%d",
+ zbr->lnum, zbr->offs);
+ dbg_tnc("looked for key %s found node's key %s",
+ DBGKEY(key), DBGKEY1(&key1));
+ dbg_dump_node(c, node);
+ return -EINVAL;
+ }
+
+ return 0;
+}
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ * Adrian Hunter
+ */
+
+/*
+ * This file describes UBIFS on-flash format and contains definitions of all the
+ * relevant data structures and constants.
+ *
+ * All UBIFS on-flash objects are stored in the form of nodes. All nodes start
+ * with the UBIFS node magic number and have the same common header. Nodes
+ * always sit at 8-byte aligned positions on the media and node header sizes are
+ * also 8-byte aligned (except for the indexing node and the padding node).
+ */
+
+#ifndef __UBIFS_MEDIA_H__
+#define __UBIFS_MEDIA_H__
+
+/* UBIFS node magic number (must not have the padding byte first or last) */
+#define UBIFS_NODE_MAGIC 0x06101831
+
+/* UBIFS on-flash format version */
+#define UBIFS_FORMAT_VERSION 4
+
+/* Minimum logical eraseblock size in bytes */
+#define UBIFS_MIN_LEB_SZ (15*1024)
+
+/* Initial CRC32 value used when calculating CRC checksums */
+#define UBIFS_CRC32_INIT 0xFFFFFFFFU
+
+/*
+ * UBIFS does not try to compress data if its length is less than the below
+ * constant.
+ */
+#define UBIFS_MIN_COMPR_LEN 128
+
+/* Root inode number */
+#define UBIFS_ROOT_INO 1
+
+/* Lowest inode number used for regular inodes (not UBIFS-only internal ones) */
+#define UBIFS_FIRST_INO 64
+
+/*
+ * Maximum file name and extended attribute length (must be a multiple of 8,
+ * minus 1).
+ */
+#define UBIFS_MAX_NLEN 255
+
+/* Maximum number of data journal heads */
+#define UBIFS_MAX_JHEADS 1
+
+/*
+ * Size of UBIFS data block. Note, UBIFS is not a block oriented file-system,
+ * which means that it does not treat the underlying media as consisting of
+ * blocks like in case of hard drives. Do not be confused. UBIFS block is just
+ * the maximum amount of data which one data node can have or which can be
+ * attached to an inode node.
+ */
+#define UBIFS_BLOCK_SIZE 4096
+#define UBIFS_BLOCK_SHIFT 12
+#define UBIFS_BLOCK_MASK 0x00000FFF
+
+/* UBIFS padding byte pattern (must not be first or last byte of node magic) */
+#define UBIFS_PADDING_BYTE 0xCE
+
+/* Maximum possible key length */
+#define UBIFS_MAX_KEY_LEN 16
+
+/* Key length ("simple" format) */
+#define UBIFS_SK_LEN 8
+
+/* Minimum index tree fanout */
+#define UBIFS_MIN_FANOUT 2
+
+/* Maximum number of levels in UBIFS indexing B-tree */
+#define UBIFS_MAX_LEVELS 512
+
+/* Maximum amount of data attached to an inode in bytes */
+#define UBIFS_MAX_INO_DATA UBIFS_BLOCK_SIZE
+
+/* LEB Properties Tree fanout (must be power of 2) and fanout shift */
+#define UBIFS_LPT_FANOUT 4
+#define UBIFS_LPT_FANOUT_SHIFT 2
+
+/* LEB Properties Tree bit field sizes */
+#define UBIFS_LPT_CRC_BITS 16
+#define UBIFS_LPT_CRC_BYTES 2
+#define UBIFS_LPT_TYPE_BITS 4
+
+/* The key is always at the same position in all keyed nodes */
+#define UBIFS_KEY_OFFSET offsetof(struct ubifs_ino_node, key)
+
+/*
+ * LEB Properties Tree node types.
+ *
+ * UBIFS_LPT_PNODE: LPT leaf node (contains LEB properties)
+ * UBIFS_LPT_NNODE: LPT internal node
+ * UBIFS_LPT_LTAB: LPT's own lprops table
+ * UBIFS_LPT_LSAVE: LPT's save table (big model only)
+ * UBIFS_LPT_NODE_CNT: count of LPT node types
+ * UBIFS_LPT_NOT_A_NODE: all ones (15 for 4 bits) is never a valid node type
+ */
+enum {
+ UBIFS_LPT_PNODE,
+ UBIFS_LPT_NNODE,
+ UBIFS_LPT_LTAB,
+ UBIFS_LPT_LSAVE,
+ UBIFS_LPT_NODE_CNT,
+ UBIFS_LPT_NOT_A_NODE = (1 << UBIFS_LPT_TYPE_BITS) - 1,
+};
+
+/*
+ * UBIFS inode types.
+ *
+ * UBIFS_ITYPE_REG: regular file
+ * UBIFS_ITYPE_DIR: directory
+ * UBIFS_ITYPE_LNK: soft link
+ * UBIFS_ITYPE_BLK: block device node
+ * UBIFS_ITYPE_CHR: character device node
+ * UBIFS_ITYPE_FIFO: fifo
+ * UBIFS_ITYPE_SOCK: socket
+ * UBIFS_ITYPES_CNT: count of supported file types
+ */
+enum {
+ UBIFS_ITYPE_REG,
+ UBIFS_ITYPE_DIR,
+ UBIFS_ITYPE_LNK,
+ UBIFS_ITYPE_BLK,
+ UBIFS_ITYPE_CHR,
+ UBIFS_ITYPE_FIFO,
+ UBIFS_ITYPE_SOCK,
+ UBIFS_ITYPES_CNT,
+};
+
+/*
+ * Supported key hash functions.
+ *
+ * UBIFS_KEY_HASH_R5: R5 hash
+ * UBIFS_KEY_HASH_TEST: test hash which just returns first 4 bytes of the name
+ */
+enum {
+ UBIFS_KEY_HASH_R5,
+ UBIFS_KEY_HASH_TEST,
+};
+
+/*
+ * Supported key formats.
+ *
+ * UBIFS_SIMPLE_KEY_FMT: simple key format
+ */
+enum {
+ UBIFS_SIMPLE_KEY_FMT,
+};
+
+/*
+ * The simple key format uses 29 bits for storing UBIFS block number and hash
+ * value.
+ */
+#define UBIFS_S_KEY_BLOCK_BITS 29
+#define UBIFS_S_KEY_BLOCK_MASK 0x1FFFFFFF
+#define UBIFS_S_KEY_HASH_BITS UBIFS_S_KEY_BLOCK_BITS
+#define UBIFS_S_KEY_HASH_MASK UBIFS_S_KEY_BLOCK_MASK
+
+/*
+ * Key types.
+ *
+ * UBIFS_INO_KEY: inode node key
+ * UBIFS_DATA_KEY: data node key
+ * UBIFS_DENT_KEY: directory entry node key
+ * UBIFS_XENT_KEY: extended attribute entry key
+ * UBIFS_KEY_TYPES_CNT: number of supported key types
+ */
+enum {
+ UBIFS_INO_KEY,
+ UBIFS_DATA_KEY,
+ UBIFS_DENT_KEY,
+ UBIFS_XENT_KEY,
+ UBIFS_KEY_TYPES_CNT,
+};
+
+/* Count of LEBs reserved for the superblock area */
+#define UBIFS_SB_LEBS 1
+/* Count of LEBs reserved for the master area */
+#define UBIFS_MST_LEBS 2
+
+/* First LEB of the superblock area */
+#define UBIFS_SB_LNUM 0
+/* First LEB of the master area */
+#define UBIFS_MST_LNUM (UBIFS_SB_LNUM + UBIFS_SB_LEBS)
+/* First LEB of the log area */
+#define UBIFS_LOG_LNUM (UBIFS_MST_LNUM + UBIFS_MST_LEBS)
+
+/*
+ * The below constants define the absolute minimum values for various UBIFS
+ * media areas. Many of them actually depend of flash geometry and the FS
+ * configuration (number of journal heads, orphan LEBs, etc). This means that
+ * the smallest volume size which can be used for UBIFS cannot be pre-defined
+ * by these constants. The file-system that meets the below limitation will not
+ * necessarily mount. UBIFS does run-time calculations and validates the FS
+ * size.
+ */
+
+/* Minimum number of logical eraseblocks in the log */
+#define UBIFS_MIN_LOG_LEBS 2
+/* Minimum number of bud logical eraseblocks (one for each head) */
+#define UBIFS_MIN_BUD_LEBS 3
+/* Minimum number of journal logical eraseblocks */
+#define UBIFS_MIN_JNL_LEBS (UBIFS_MIN_LOG_LEBS + UBIFS_MIN_BUD_LEBS)
+/* Minimum number of LPT area logical eraseblocks */
+#define UBIFS_MIN_LPT_LEBS 2
+/* Minimum number of orphan area logical eraseblocks */
+#define UBIFS_MIN_ORPH_LEBS 1
+/*
+ * Minimum number of main area logical eraseblocks (buds, 2 for the index, 1
+ * for GC, 1 for deletions, and at least 1 for committed data).
+ */
+#define UBIFS_MIN_MAIN_LEBS (UBIFS_MIN_BUD_LEBS + 5)
+
+/* Minimum number of logical eraseblocks */
+#define UBIFS_MIN_LEB_CNT (UBIFS_SB_LEBS + UBIFS_MST_LEBS + \
+ UBIFS_MIN_LOG_LEBS + UBIFS_MIN_LPT_LEBS + \
+ UBIFS_MIN_ORPH_LEBS + UBIFS_MIN_MAIN_LEBS)
+
+/* Node sizes (N.B. these are guaranteed to be multiples of 8) */
+#define UBIFS_CH_SZ sizeof(struct ubifs_ch)
+#define UBIFS_INO_NODE_SZ sizeof(struct ubifs_ino_node)
+#define UBIFS_DATA_NODE_SZ sizeof(struct ubifs_data_node)
+#define UBIFS_DENT_NODE_SZ sizeof(struct ubifs_dent_node)
+#define UBIFS_TRUN_NODE_SZ sizeof(struct ubifs_trun_node)
+#define UBIFS_PAD_NODE_SZ sizeof(struct ubifs_pad_node)
+#define UBIFS_SB_NODE_SZ sizeof(struct ubifs_sb_node)
+#define UBIFS_MST_NODE_SZ sizeof(struct ubifs_mst_node)
+#define UBIFS_REF_NODE_SZ sizeof(struct ubifs_ref_node)
+#define UBIFS_IDX_NODE_SZ sizeof(struct ubifs_idx_node)
+#define UBIFS_CS_NODE_SZ sizeof(struct ubifs_cs_node)
+#define UBIFS_ORPH_NODE_SZ sizeof(struct ubifs_orph_node)
+/* Extended attribute entry nodes are identical to directory entry nodes */
+#define UBIFS_XENT_NODE_SZ UBIFS_DENT_NODE_SZ
+/* Only this does not have to be multiple of 8 bytes */
+#define UBIFS_BRANCH_SZ sizeof(struct ubifs_branch)
+
+/* Maximum node sizes (N.B. these are guaranteed to be multiples of 8) */
+#define UBIFS_MAX_DATA_NODE_SZ (UBIFS_DATA_NODE_SZ + UBIFS_BLOCK_SIZE)
+#define UBIFS_MAX_INO_NODE_SZ (UBIFS_INO_NODE_SZ + UBIFS_MAX_INO_DATA)
+#define UBIFS_MAX_DENT_NODE_SZ (UBIFS_DENT_NODE_SZ + UBIFS_MAX_NLEN + 1)
+#define UBIFS_MAX_XENT_NODE_SZ UBIFS_MAX_DENT_NODE_SZ
+
+/* The largest UBIFS node */
+#define UBIFS_MAX_NODE_SZ UBIFS_MAX_INO_NODE_SZ
+
+/*
+ * On-flash inode flags.
+ *
+ * UBIFS_COMPR_FL: use compression for this inode
+ * UBIFS_SYNC_FL: I/O on this inode has to be synchronous
+ * UBIFS_IMMUTABLE_FL: inode is immutable
+ * UBIFS_APPEND_FL: writes to the inode may only append data
+ * UBIFS_DIRSYNC_FL: I/O on this directory inode has to be synchronous
+ * UBIFS_XATTR_FL: this inode is the inode for an extended attribute value
+ *
+ * Note, these are on-flash flags which correspond to ioctl flags
+ * (@FS_COMPR_FL, etc). They have the same values now, but generally, do not
+ * have to be the same.
+ */
+enum {
+ UBIFS_COMPR_FL = 0x01,
+ UBIFS_SYNC_FL = 0x02,
+ UBIFS_IMMUTABLE_FL = 0x04,
+ UBIFS_APPEND_FL = 0x08,
+ UBIFS_DIRSYNC_FL = 0x10,
+ UBIFS_XATTR_FL = 0x20,
+};
+
+/* Inode flag bits used by UBIFS */
+#define UBIFS_FL_MASK 0x0000001F
+
+/*
+ * UBIFS compression algorithms.
+ *
+ * UBIFS_COMPR_NONE: no compression
+ * UBIFS_COMPR_LZO: LZO compression
+ * UBIFS_COMPR_ZLIB: ZLIB compression
+ * UBIFS_COMPR_TYPES_CNT: count of supported compression types
+ */
+enum {
+ UBIFS_COMPR_NONE,
+ UBIFS_COMPR_LZO,
+ UBIFS_COMPR_ZLIB,
+ UBIFS_COMPR_TYPES_CNT,
+};
+
+/*
+ * UBIFS node types.
+ *
+ * UBIFS_INO_NODE: inode node
+ * UBIFS_DATA_NODE: data node
+ * UBIFS_DENT_NODE: directory entry node
+ * UBIFS_XENT_NODE: extended attribute node
+ * UBIFS_TRUN_NODE: truncation node
+ * UBIFS_PAD_NODE: padding node
+ * UBIFS_SB_NODE: superblock node
+ * UBIFS_MST_NODE: master node
+ * UBIFS_REF_NODE: LEB reference node
+ * UBIFS_IDX_NODE: index node
+ * UBIFS_CS_NODE: commit start node
+ * UBIFS_ORPH_NODE: orphan node
+ * UBIFS_NODE_TYPES_CNT: count of supported node types
+ *
+ * Note, we index arrays by these numbers, so keep them low and contiguous.
+ * Node type constants for inodes, direntries and so on have to be the same as
+ * corresponding key type constants.
+ */
+enum {
+ UBIFS_INO_NODE,
+ UBIFS_DATA_NODE,
+ UBIFS_DENT_NODE,
+ UBIFS_XENT_NODE,
+ UBIFS_TRUN_NODE,
+ UBIFS_PAD_NODE,
+ UBIFS_SB_NODE,
+ UBIFS_MST_NODE,
+ UBIFS_REF_NODE,
+ UBIFS_IDX_NODE,
+ UBIFS_CS_NODE,
+ UBIFS_ORPH_NODE,
+ UBIFS_NODE_TYPES_CNT,
+};
+
+/*
+ * Master node flags.
+ *
+ * UBIFS_MST_DIRTY: rebooted uncleanly - master node is dirty
+ * UBIFS_MST_NO_ORPHS: no orphan inodes present
+ * UBIFS_MST_RCVRY: written by recovery
+ */
+enum {
+ UBIFS_MST_DIRTY = 1,
+ UBIFS_MST_NO_ORPHS = 2,
+ UBIFS_MST_RCVRY = 4,
+};
+
+/*
+ * Node group type (used by recovery to recover whole group or none).
+ *
+ * UBIFS_NO_NODE_GROUP: this node is not part of a group
+ * UBIFS_IN_NODE_GROUP: this node is a part of a group
+ * UBIFS_LAST_OF_NODE_GROUP: this node is the last in a group
+ */
+enum {
+ UBIFS_NO_NODE_GROUP = 0,
+ UBIFS_IN_NODE_GROUP,
+ UBIFS_LAST_OF_NODE_GROUP,
+};
+
+/*
+ * Superblock flags.
+ *
+ * UBIFS_FLG_BIGLPT: if "big" LPT model is used if set
+ */
+enum {
+ UBIFS_FLG_BIGLPT = 0x02,
+};
+
+/**
+ * struct ubifs_ch - common header node.
+ * @magic: UBIFS node magic number (%UBIFS_NODE_MAGIC)
+ * @crc: CRC-32 checksum of the node header
+ * @sqnum: sequence number
+ * @len: full node length
+ * @node_type: node type
+ * @group_type: node group type
+ * @padding: reserved for future, zeroes
+ *
+ * Every UBIFS node starts with this common part. If the node has a key, the
+ * key always goes next.
+ */
+struct ubifs_ch {
+ __le32 magic;
+ __le32 crc;
+ __le64 sqnum;
+ __le32 len;
+ __u8 node_type;
+ __u8 group_type;
+ __u8 padding[2];
+} __attribute__ ((packed));
+
+/**
+ * union ubifs_dev_desc - device node descriptor.
+ * @new: new type device descriptor
+ * @huge: huge type device descriptor
+ *
+ * This data structure describes major/minor numbers of a device node. In an
+ * inode is a device node then its data contains an object of this type. UBIFS
+ * uses standard Linux "new" and "huge" device node encodings.
+ */
+union ubifs_dev_desc {
+ __le32 new;
+ __le64 huge;
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_ino_node - inode node.
+ * @ch: common header
+ * @key: node key
+ * @creat_sqnum: sequence number at time of creation
+ * @size: inode size in bytes (amount of uncompressed data)
+ * @atime_sec: access time seconds
+ * @ctime_sec: creation time seconds
+ * @mtime_sec: modification time seconds
+ * @atime_nsec: access time nanoseconds
+ * @ctime_nsec: creation time nanoseconds
+ * @mtime_nsec: modification time nanoseconds
+ * @nlink: number of hard links
+ * @uid: owner ID
+ * @gid: group ID
+ * @mode: access flags
+ * @flags: per-inode flags (%UBIFS_COMPR_FL, %UBIFS_SYNC_FL, etc)
+ * @data_len: inode data length
+ * @xattr_cnt: count of extended attributes this inode has
+ * @xattr_size: summarized size of all extended attributes in bytes
+ * @padding1: reserved for future, zeroes
+ * @xattr_names: sum of lengths of all extended attribute names belonging to
+ * this inode
+ * @compr_type: compression type used for this inode
+ * @padding2: reserved for future, zeroes
+ * @data: data attached to the inode
+ *
+ * Note, even though inode compression type is defined by @compr_type, some
+ * nodes of this inode may be compressed with different compressor - this
+ * happens if compression type is changed while the inode already has data
+ * nodes. But @compr_type will be use for further writes to the inode.
+ *
+ * Note, do not forget to amend 'zero_ino_node_unused()' function when changing
+ * the padding fields.
+ */
+struct ubifs_ino_node {
+ struct ubifs_ch ch;
+ __u8 key[UBIFS_MAX_KEY_LEN];
+ __le64 creat_sqnum;
+ __le64 size;
+ __le64 atime_sec;
+ __le64 ctime_sec;
+ __le64 mtime_sec;
+ __le32 atime_nsec;
+ __le32 ctime_nsec;
+ __le32 mtime_nsec;
+ __le32 nlink;
+ __le32 uid;
+ __le32 gid;
+ __le32 mode;
+ __le32 flags;
+ __le32 data_len;
+ __le32 xattr_cnt;
+ __le32 xattr_size;
+ __u8 padding1[4]; /* Watch 'zero_ino_node_unused()' if changing! */
+ __le32 xattr_names;
+ __le16 compr_type;
+ __u8 padding2[26]; /* Watch 'zero_ino_node_unused()' if changing! */
+ __u8 data[];
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_dent_node - directory entry node.
+ * @ch: common header
+ * @key: node key
+ * @inum: target inode number
+ * @padding1: reserved for future, zeroes
+ * @type: type of the target inode (%UBIFS_ITYPE_REG, %UBIFS_ITYPE_DIR, etc)
+ * @nlen: name length
+ * @padding2: reserved for future, zeroes
+ * @name: zero-terminated name
+ *
+ * Note, do not forget to amend 'zero_dent_node_unused()' function when
+ * changing the padding fields.
+ */
+struct ubifs_dent_node {
+ struct ubifs_ch ch;
+ __u8 key[UBIFS_MAX_KEY_LEN];
+ __le64 inum;
+ __u8 padding1;
+ __u8 type;
+ __le16 nlen;
+ __u8 padding2[4]; /* Watch 'zero_dent_node_unused()' if changing! */
+ __u8 name[];
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_data_node - data node.
+ * @ch: common header
+ * @key: node key
+ * @size: uncompressed data size in bytes
+ * @compr_type: compression type (%UBIFS_COMPR_NONE, %UBIFS_COMPR_LZO, etc)
+ * @padding: reserved for future, zeroes
+ * @data: data
+ *
+ * Note, do not forget to amend 'zero_data_node_unused()' function when
+ * changing the padding fields.
+ */
+struct ubifs_data_node {
+ struct ubifs_ch ch;
+ __u8 key[UBIFS_MAX_KEY_LEN];
+ __le32 size;
+ __le16 compr_type;
+ __u8 padding[2]; /* Watch 'zero_data_node_unused()' if changing! */
+ __u8 data[];
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_trun_node - truncation node.
+ * @ch: common header
+ * @inum: truncated inode number
+ * @padding: reserved for future, zeroes
+ * @old_size: size before truncation
+ * @new_size: size after truncation
+ *
+ * This node exists only in the journal and never goes to the main area. Note,
+ * do not forget to amend 'zero_trun_node_unused()' function when changing the
+ * padding fields.
+ */
+struct ubifs_trun_node {
+ struct ubifs_ch ch;
+ __le32 inum;
+ __u8 padding[12]; /* Watch 'zero_trun_node_unused()' if changing! */
+ __le64 old_size;
+ __le64 new_size;
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_pad_node - padding node.
+ * @ch: common header
+ * @pad_len: how many bytes after this node are unused (because padded)
+ * @padding: reserved for future, zeroes
+ */
+struct ubifs_pad_node {
+ struct ubifs_ch ch;
+ __le32 pad_len;
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_sb_node - superblock node.
+ * @ch: common header
+ * @padding: reserved for future, zeroes
+ * @key_hash: type of hash function used in keys
+ * @key_fmt: format of the key
+ * @flags: file-system flags (%UBIFS_FLG_BIGLPT, etc)
+ * @min_io_size: minimal input/output unit size
+ * @leb_size: logical eraseblock size in bytes
+ * @leb_cnt: count of LEBs used by file-system
+ * @max_leb_cnt: maximum count of LEBs used by file-system
+ * @max_bud_bytes: maximum amount of data stored in buds
+ * @log_lebs: log size in logical eraseblocks
+ * @lpt_lebs: number of LEBs used for lprops table
+ * @orph_lebs: number of LEBs used for recording orphans
+ * @jhead_cnt: count of journal heads
+ * @fanout: tree fanout (max. number of links per indexing node)
+ * @lsave_cnt: number of LEB numbers in LPT's save table
+ * @fmt_version: UBIFS on-flash format version
+ * @default_compr: default compression algorithm (%UBIFS_COMPR_LZO, etc)
+ * @padding1: reserved for future, zeroes
+ * @rp_uid: reserve pool UID
+ * @rp_gid: reserve pool GID
+ * @rp_size: size of the reserved pool in bytes
+ * @padding2: reserved for future, zeroes
+ * @time_gran: time granularity in nanoseconds
+ * @uuid: UUID generated when the file system image was created
+ */
+struct ubifs_sb_node {
+ struct ubifs_ch ch;
+ __u8 padding[2];
+ __u8 key_hash;
+ __u8 key_fmt;
+ __le32 flags;
+ __le32 min_io_size;
+ __le32 leb_size;
+ __le32 leb_cnt;
+ __le32 max_leb_cnt;
+ __le64 max_bud_bytes;
+ __le32 log_lebs;
+ __le32 lpt_lebs;
+ __le32 orph_lebs;
+ __le32 jhead_cnt;
+ __le32 fanout;
+ __le32 lsave_cnt;
+ __le32 fmt_version;
+ __le16 default_compr;
+ __u8 padding1[2];
+ __le32 rp_uid;
+ __le32 rp_gid;
+ __le64 rp_size;
+ __le32 time_gran;
+ __u8 uuid[16];
+ __u8 padding2[3972];
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_mst_node - master node.
+ * @ch: common header
+ * @highest_inum: highest inode number in the committed index
+ * @cmt_no: commit number
+ * @flags: various flags (%UBIFS_MST_DIRTY, etc)
+ * @log_lnum: start of the log
+ * @root_lnum: LEB number of the root indexing node
+ * @root_offs: offset within @root_lnum
+ * @root_len: root indexing node length
+ * @gc_lnum: LEB reserved for garbage collection (%-1 value means the LEB was
+ * not reserved and should be reserved on mount)
+ * @ihead_lnum: LEB number of index head
+ * @ihead_offs: offset of index head
+ * @index_size: size of index on flash
+ * @total_free: total free space in bytes
+ * @total_dirty: total dirty space in bytes
+ * @total_used: total used space in bytes (includes only data LEBs)
+ * @total_dead: total dead space in bytes (includes only data LEBs)
+ * @total_dark: total dark space in bytes (includes only data LEBs)
+ * @lpt_lnum: LEB number of LPT root nnode
+ * @lpt_offs: offset of LPT root nnode
+ * @nhead_lnum: LEB number of LPT head
+ * @nhead_offs: offset of LPT head
+ * @ltab_lnum: LEB number of LPT's own lprops table
+ * @ltab_offs: offset of LPT's own lprops table
+ * @lsave_lnum: LEB number of LPT's save table (big model only)
+ * @lsave_offs: offset of LPT's save table (big model only)
+ * @lscan_lnum: LEB number of last LPT scan
+ * @empty_lebs: number of empty logical eraseblocks
+ * @idx_lebs: number of indexing logical eraseblocks
+ * @leb_cnt: count of LEBs used by file-system
+ * @padding: reserved for future, zeroes
+ */
+struct ubifs_mst_node {
+ struct ubifs_ch ch;
+ __le64 highest_inum;
+ __le64 cmt_no;
+ __le32 flags;
+ __le32 log_lnum;
+ __le32 root_lnum;
+ __le32 root_offs;
+ __le32 root_len;
+ __le32 gc_lnum;
+ __le32 ihead_lnum;
+ __le32 ihead_offs;
+ __le64 index_size;
+ __le64 total_free;
+ __le64 total_dirty;
+ __le64 total_used;
+ __le64 total_dead;
+ __le64 total_dark;
+ __le32 lpt_lnum;
+ __le32 lpt_offs;
+ __le32 nhead_lnum;
+ __le32 nhead_offs;
+ __le32 ltab_lnum;
+ __le32 ltab_offs;
+ __le32 lsave_lnum;
+ __le32 lsave_offs;
+ __le32 lscan_lnum;
+ __le32 empty_lebs;
+ __le32 idx_lebs;
+ __le32 leb_cnt;
+ __u8 padding[344];
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_ref_node - logical eraseblock reference node.
+ * @ch: common header
+ * @lnum: the referred logical eraseblock number
+ * @offs: start offset in the referred LEB
+ * @jhead: journal head number
+ * @padding: reserved for future, zeroes
+ */
+struct ubifs_ref_node {
+ struct ubifs_ch ch;
+ __le32 lnum;
+ __le32 offs;
+ __le32 jhead;
+ __u8 padding[28];
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_branch - key/reference/length branch
+ * @lnum: LEB number of the target node
+ * @offs: offset within @lnum
+ * @len: target node length
+ * @key: key
+ */
+struct ubifs_branch {
+ __le32 lnum;
+ __le32 offs;
+ __le32 len;
+ __u8 key[];
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_idx_node - indexing node.
+ * @ch: common header
+ * @child_cnt: number of child index nodes
+ * @level: tree level
+ * @branches: LEB number / offset / length / key branches
+ */
+struct ubifs_idx_node {
+ struct ubifs_ch ch;
+ __le16 child_cnt;
+ __le16 level;
+ __u8 branches[];
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_cs_node - commit start node.
+ * @ch: common header
+ * @cmt_no: commit number
+ */
+struct ubifs_cs_node {
+ struct ubifs_ch ch;
+ __le64 cmt_no;
+} __attribute__ ((packed));
+
+/**
+ * struct ubifs_orph_node - orphan node.
+ * @ch: common header
+ * @cmt_no: commit number (also top bit is set on the last node of the commit)
+ * @inos: inode numbers of orphans
+ */
+struct ubifs_orph_node {
+ struct ubifs_ch ch;
+ __le64 cmt_no;
+ __le64 inos[];
+} __attribute__ ((packed));
+
+#endif /* __UBIFS_MEDIA_H__ */
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ * Adrian Hunter
+ */
+
+/* Implementation version 0.7 */
+
+#ifndef __UBIFS_H__
+#define __UBIFS_H__
+
+#include <asm/div64.h>
+#include <linux/statfs.h>
+#include <linux/fs.h>
+#include <linux/err.h>
+#include <linux/sched.h>
+#include <linux/vmalloc.h>
+#include <linux/spinlock.h>
+#include <linux/mutex.h>
+#include <linux/rwsem.h>
+#include <linux/mtd/ubi.h>
+#include <linux/pagemap.h>
+#include <linux/backing-dev.h>
+#include "ubifs-media.h"
+
+/* Version of this UBIFS implementation */
+#define UBIFS_VERSION 1
+
+/* Normal UBIFS messages */
+#define ubifs_msg(fmt, ...) \
+ printk(KERN_NOTICE "UBIFS: " fmt "\n", ##__VA_ARGS__)
+/* UBIFS error messages */
+#define ubifs_err(fmt, ...) \
+ printk(KERN_ERR "UBIFS error (pid %d): %s: " fmt "\n", current->pid, \
+ __func__, ##__VA_ARGS__)
+/* UBIFS warning messages */
+#define ubifs_warn(fmt, ...) \
+ printk(KERN_WARNING "UBIFS warning (pid %d): %s: " fmt "\n", \
+ current->pid, __func__, ##__VA_ARGS__)
+
+/* UBIFS file system VFS magic number */
+#define UBIFS_SUPER_MAGIC 0x24051905
+
+/* Number of UBIFS blocks per VFS page */
+#define UBIFS_BLOCKS_PER_PAGE (PAGE_CACHE_SIZE / UBIFS_BLOCK_SIZE)
+#define UBIFS_BLOCKS_PER_PAGE_SHIFT (PAGE_CACHE_SHIFT - UBIFS_BLOCK_SHIFT)
+
+/* "File system end of life" sequence number watermark */
+#define SQNUM_WARN_WATERMARK 0xFFFFFFFF00000000ULL
+#define SQNUM_WATERMARK 0xFFFFFFFFFF000000ULL
+
+/* Minimum amount of data UBIFS writes to the flash */
+#define MIN_WRITE_SZ (UBIFS_DATA_NODE_SZ + 8)
+
+/*
+ * Currently we do not support inode number overlapping and re-using, so this
+ * watermark defines dangerous inode number level. This should be fixed later,
+ * although it is difficult to exceed current limit. Another option is to use
+ * 64-bit inode numbers, but this means more overhead.
+ */
+#define INUM_WARN_WATERMARK 0xFFF00000
+#define INUM_WATERMARK 0xFFFFFF00
+
+/* Largest key size supported in this implementation */
+#define CUR_MAX_KEY_LEN UBIFS_SK_LEN
+
+/* Maximum number of entries in each LPT (LEB category) heap */
+#define LPT_HEAP_SZ 256
+
+/*
+ * Background thread name pattern. The numbers are UBI device and volume
+ * numbers.
+ */
+#define BGT_NAME_PATTERN "ubifs_bgt%d_%d"
+
+/* Default write-buffer synchronization timeout (5 secs) */
+#define DEFAULT_WBUF_TIMEOUT (5 * HZ)
+
+/* Maximum possible inode number (only 32-bit inodes are supported now) */
+#define MAX_INUM 0xFFFFFFFF
+
+/* Number of non-data journal heads */
+#define NONDATA_JHEADS_CNT 2
+
+/* Garbage collector head */
+#define GCHD 0
+/* Base journal head number */
+#define BASEHD 1
+/* First "general purpose" journal head */
+#define DATAHD 2
+
+/* 'No change' value for 'ubifs_change_lp()' */
+#define LPROPS_NC 0x80000001
+
+/*
+ * There is no notion of truncation key because truncation nodes do not exist
+ * in TNC. However, when replaying, it is handy to introduce fake "truncation"
+ * keys for truncation nodes because the code becomes simpler. So we define
+ * %UBIFS_TRUN_KEY type.
+ */
+#define UBIFS_TRUN_KEY UBIFS_KEY_TYPES_CNT
+
+/*
+ * How much a directory entry/extended attribute entry adds to the parent/host
+ * inode.
+ */
+#define CALC_DENT_SIZE(name_len) ALIGN(UBIFS_DENT_NODE_SZ + (name_len) + 1, 8)
+
+/* How much an extended attribute adds to the host inode */
+#define CALC_XATTR_BYTES(data_len) ALIGN(UBIFS_INO_NODE_SZ + (data_len) + 1, 8)
+
+/*
+ * Znodes which were not touched for 'OLD_ZNODE_AGE' seconds are considered
+ * "old", and znode which were touched last 'YOUNG_ZNODE_AGE' seconds ago are
+ * considered "young". This is used by shrinker when selecting znode to trim
+ * off.
+ */
+#define OLD_ZNODE_AGE 20
+#define YOUNG_ZNODE_AGE 5
+
+/*
+ * Some compressors, like LZO, may end up with more data then the input buffer.
+ * So UBIFS always allocates larger output buffer, to be sure the compressor
+ * will not corrupt memory in case of worst case compression.
+ */
+#define WORST_COMPR_FACTOR 2
+
+/* Maximum expected tree height for use by bottom_up_buf */
+#define BOTTOM_UP_HEIGHT 64
+
+/*
+ * Lockdep classes for UBIFS inode @ui_mutex.
+ */
+enum {
+ WB_MUTEX_1 = 0,
+ WB_MUTEX_2 = 1,
+ WB_MUTEX_3 = 2,
+};
+
+/*
+ * Znode flags (actually, bit numbers which store the flags).
+ *
+ * DIRTY_ZNODE: znode is dirty
+ * COW_ZNODE: znode is being committed and a new instance of this znode has to
+ * be created before changing this znode
+ * OBSOLETE_ZNODE: znode is obsolete, which means it was deleted, but it is
+ * still in the commit list and the ongoing commit operation
+ * will commit it, and delete this znode after it is done
+ */
+enum {
+ DIRTY_ZNODE = 0,
+ COW_ZNODE = 1,
+ OBSOLETE_ZNODE = 2,
+};
+
+/*
+ * Commit states.
+ *
+ * COMMIT_RESTING: commit is not wanted
+ * COMMIT_BACKGROUND: background commit has been requested
+ * COMMIT_REQUIRED: commit is required
+ * COMMIT_RUNNING_BACKGROUND: background commit is running
+ * COMMIT_RUNNING_REQUIRED: commit is running and it is required
+ * COMMIT_BROKEN: commit failed
+ */
+enum {
+ COMMIT_RESTING = 0,
+ COMMIT_BACKGROUND,
+ COMMIT_REQUIRED,
+ COMMIT_RUNNING_BACKGROUND,
+ COMMIT_RUNNING_REQUIRED,
+ COMMIT_BROKEN,
+};
+
+/*
+ * 'ubifs_scan_a_node()' return values.
+ *
+ * SCANNED_GARBAGE: scanned garbage
+ * SCANNED_EMPTY_SPACE: scanned empty space
+ * SCANNED_A_NODE: scanned a valid node
+ * SCANNED_A_CORRUPT_NODE: scanned a corrupted node
+ * SCANNED_A_BAD_PAD_NODE: scanned a padding node with invalid pad length
+ *
+ * Greater than zero means: 'scanned that number of padding bytes'
+ */
+enum {
+ SCANNED_GARBAGE = 0,
+ SCANNED_EMPTY_SPACE = -1,
+ SCANNED_A_NODE = -2,
+ SCANNED_A_CORRUPT_NODE = -3,
+ SCANNED_A_BAD_PAD_NODE = -4,
+};
+
+/*
+ * LPT cnode flag bits.
+ *
+ * DIRTY_CNODE: cnode is dirty
+ * COW_CNODE: cnode is being committed and must be copied before writing
+ * OBSOLETE_CNODE: cnode is being committed and has been copied (or deleted),
+ * so it can (and must) be freed when the commit is finished
+ */
+enum {
+ DIRTY_CNODE = 0,
+ COW_CNODE = 1,
+ OBSOLETE_CNODE = 2,
+};
+
+/*
+ * Dirty flag bits (lpt_drty_flgs) for LPT special nodes.
+ *
+ * LTAB_DIRTY: ltab node is dirty
+ * LSAVE_DIRTY: lsave node is dirty
+ */
+enum {
+ LTAB_DIRTY = 1,
+ LSAVE_DIRTY = 2,
+};
+
+/*
+ * Return codes used by the garbage collector.
+ * @LEB_FREED: the logical eraseblock was freed and is ready to use
+ * @LEB_FREED_IDX: indexing LEB was freed and can be used only after the commit
+ * @LEB_RETAINED: the logical eraseblock was freed and retained for GC purposes
+ */
+enum {
+ LEB_FREED,
+ LEB_FREED_IDX,
+ LEB_RETAINED,
+};
+
+/**
+ * struct ubifs_old_idx - index node obsoleted since last commit start.
+ * @rb: rb-tree node
+ * @lnum: LEB number of obsoleted index node
+ * @offs: offset of obsoleted index node
+ */
+struct ubifs_old_idx {
+ struct rb_node rb;
+ int lnum;
+ int offs;
+};
+
+/* The below union makes it easier to deal with keys */
+union ubifs_key {
+ uint8_t u8[CUR_MAX_KEY_LEN];
+ uint32_t u32[CUR_MAX_KEY_LEN/4];
+ uint64_t u64[CUR_MAX_KEY_LEN/8];
+ __le32 j32[CUR_MAX_KEY_LEN/4];
+};
+
+/**
+ * struct ubifs_scan_node - UBIFS scanned node information.
+ * @list: list of scanned nodes
+ * @key: key of node scanned (if it has one)
+ * @sqnum: sequence number
+ * @type: type of node scanned
+ * @offs: offset with LEB of node scanned
+ * @len: length of node scanned
+ * @node: raw node
+ */
+struct ubifs_scan_node {
+ struct list_head list;
+ union ubifs_key key;
+ unsigned long long sqnum;
+ int type;
+ int offs;
+ int len;
+ void *node;
+};
+
+/**
+ * struct ubifs_scan_leb - UBIFS scanned LEB information.
+ * @lnum: logical eraseblock number
+ * @nodes_cnt: number of nodes scanned
+ * @nodes: list of struct ubifs_scan_node
+ * @endpt: end point (and therefore the start of empty space)
+ * @ecc: read returned -EBADMSG
+ * @buf: buffer containing entire LEB scanned
+ */
+struct ubifs_scan_leb {
+ int lnum;
+ int nodes_cnt;
+ struct list_head nodes;
+ int endpt;
+ int ecc;
+ void *buf;
+};
+
+/**
+ * struct ubifs_gced_idx_leb - garbage-collected indexing LEB.
+ * @list: list
+ * @lnum: LEB number
+ * @unmap: OK to unmap this LEB
+ *
+ * This data structure is used to temporary store garbage-collected indexing
+ * LEBs - they are not released immediately, but only after the next commit.
+ * This is needed to guarantee recoverability.
+ */
+struct ubifs_gced_idx_leb {
+ struct list_head list;
+ int lnum;
+ int unmap;
+};
+
+/**
+ * struct ubifs_inode - UBIFS in-memory inode description.
+ * @vfs_inode: VFS inode description object
+ * @creat_sqnum: sequence number at time of creation
+ * @xattr_size: summarized size of all extended attributes in bytes
+ * @xattr_cnt: count of extended attributes this inode has
+ * @xattr_names: sum of lengths of all extended attribute names belonging to
+ * this inode
+ * @dirty: non-zero if the inode is dirty
+ * @xattr: non-zero if this is an extended attribute inode
+ * @ui_mutex: serializes inode write-back with the rest of VFS operations,
+ * serializes "clean <-> dirty" state changes, protects @dirty,
+ * @ui_size, and @xattr_size
+ * @ui_lock: protects @synced_i_size
+ * @synced_i_size: synchronized size of inode, i.e. the value of inode size
+ * currently stored on the flash; used only for regular file
+ * inodes
+ * @ui_size: inode size used by UBIFS when writing to flash
+ * @flags: inode flags (@UBIFS_COMPR_FL, etc)
+ * @compr_type: default compression type used for this inode
+ * @data_len: length of the data attached to the inode
+ * @data: inode's data
+ *
+ * @ui_mutex exists for two main reasons. At first it prevents inodes from
+ * being written back while UBIFS changing them, being in the middle of an VFS
+ * operation. This way UBIFS makes sure the inode fields are consistent. For
+ * example, in 'ubifs_rename()' we change 3 inodes simultaneously, and
+ * write-back must not write any of them before we have finished.
+ *
+ * The second reason is budgeting - UBIFS has to budget all operations. If an
+ * operation is going to mark an inode dirty, it has to allocate budget for
+ * this. It cannot just mark it dirty because there is no guarantee there will
+ * be enough flash space to write the inode back later. This means UBIFS has
+ * to have full control over inode "clean <-> dirty" transitions (and pages
+ * actually). But unfortunately, VFS marks inodes dirty in many places, and it
+ * does not ask the file-system if it is allowed to do so (there is a notifier,
+ * but it is not enough), i.e., there is no mechanism to synchronize with this.
+ * So UBIFS has its own inode dirty flag and its own mutex to serialize
+ * "clean <-> dirty" transitions.
+ *
+ * The @synced_i_size field is used to make sure we never write pages which are
+ * beyond last synchronized inode size. See 'ubifs_writepage()' for more
+ * information.
+ *
+ * The @ui_size is a "shadow" variable for @inode->i_size and UBIFS uses
+ * @ui_size instead of @inode->i_size. The reason for this is that UBIFS cannot
+ * make sure @inode->i_size is always changed under @ui_mutex, because it
+ * cannot call 'vmtruncate()' with @ui_mutex locked, because it would deadlock
+ * with 'ubifs_writepage()' (see file.c). All the other inode fields are
+ * changed under @ui_mutex, so they do not need "shadow" fields. Note, one
+ * could consider to rework locking and base it on "shadow" fields.
+ */
+struct ubifs_inode {
+ struct inode vfs_inode;
+ unsigned long long creat_sqnum;
+ unsigned int xattr_size;
+ unsigned int xattr_cnt;
+ unsigned int xattr_names;
+ unsigned int dirty:1;
+ unsigned int xattr:1;
+ struct mutex ui_mutex;
+ spinlock_t ui_lock;
+ loff_t synced_i_size;
+ loff_t ui_size;
+ int flags;
+ int compr_type;
+ int data_len;
+ void *data;
+};
+
+/**
+ * struct ubifs_unclean_leb - records a LEB recovered under read-only mode.
+ * @list: list
+ * @lnum: LEB number of recovered LEB
+ * @endpt: offset where recovery ended
+ *
+ * This structure records a LEB identified during recovery that needs to be
+ * cleaned but was not because UBIFS was mounted read-only. The information
+ * is used to clean the LEB when remounting to read-write mode.
+ */
+struct ubifs_unclean_leb {
+ struct list_head list;
+ int lnum;
+ int endpt;
+};
+
+/*
+ * LEB properties flags.
+ *
+ * LPROPS_UNCAT: not categorized
+ * LPROPS_DIRTY: dirty > 0, not index
+ * LPROPS_DIRTY_IDX: dirty + free > UBIFS_CH_SZ and index
+ * LPROPS_FREE: free > 0, not empty, not index
+ * LPROPS_HEAP_CNT: number of heaps used for storing categorized LEBs
+ * LPROPS_EMPTY: LEB is empty, not taken
+ * LPROPS_FREEABLE: free + dirty == leb_size, not index, not taken
+ * LPROPS_FRDI_IDX: free + dirty == leb_size and index, may be taken
+ * LPROPS_CAT_MASK: mask for the LEB categories above
+ * LPROPS_TAKEN: LEB was taken (this flag is not saved on the media)
+ * LPROPS_INDEX: LEB contains indexing nodes (this flag also exists on flash)
+ */
+enum {
+ LPROPS_UNCAT = 0,
+ LPROPS_DIRTY = 1,
+ LPROPS_DIRTY_IDX = 2,
+ LPROPS_FREE = 3,
+ LPROPS_HEAP_CNT = 3,
+ LPROPS_EMPTY = 4,
+ LPROPS_FREEABLE = 5,
+ LPROPS_FRDI_IDX = 6,
+ LPROPS_CAT_MASK = 15,
+ LPROPS_TAKEN = 16,
+ LPROPS_INDEX = 32,
+};
+
+/**
+ * struct ubifs_lprops - logical eraseblock properties.
+ * @free: amount of free space in bytes
+ * @dirty: amount of dirty space in bytes
+ * @flags: LEB properties flags (see above)
+ * @lnum: LEB number
+ * @list: list of same-category lprops (for LPROPS_EMPTY and LPROPS_FREEABLE)
+ * @hpos: heap position in heap of same-category lprops (other categories)
+ */
+struct ubifs_lprops {
+ int free;
+ int dirty;
+ int flags;
+ int lnum;
+ union {
+ struct list_head list;
+ int hpos;
+ };
+};
+
+/**
+ * struct ubifs_lpt_lprops - LPT logical eraseblock properties.
+ * @free: amount of free space in bytes
+ * @dirty: amount of dirty space in bytes
+ * @tgc: trivial GC flag (1 => unmap after commit end)
+ * @cmt: commit flag (1 => reserved for commit)
+ */
+struct ubifs_lpt_lprops {
+ int free;
+ int dirty;
+ unsigned tgc : 1;
+ unsigned cmt : 1;
+};
+
+/**
+ * struct ubifs_lp_stats - statistics of eraseblocks in the main area.
+ * @empty_lebs: number of empty LEBs
+ * @taken_empty_lebs: number of taken LEBs
+ * @idx_lebs: number of indexing LEBs
+ * @total_free: total free space in bytes
+ * @total_dirty: total dirty space in bytes
+ * @total_used: total used space in bytes (includes only data LEBs)
+ * @total_dead: total dead space in bytes (includes only data LEBs)
+ * @total_dark: total dark space in bytes (includes only data LEBs)
+ *
+ * N.B. total_dirty and total_used are different to other total_* fields,
+ * because they account _all_ LEBs, not just data LEBs.
+ *
+ * 'taken_empty_lebs' counts the LEBs that are in the transient state of having
+ * been 'taken' for use but not yet written to. 'taken_empty_lebs' is needed
+ * to account correctly for gc_lnum, otherwise 'empty_lebs' could be used
+ * by itself (in which case 'unused_lebs' would be a better name). In the case
+ * of gc_lnum, it is 'taken' at mount time or whenever a LEB is retained by GC,
+ * but unlike other empty LEBs that are 'taken', it may not be written straight
+ * away (i.e. before the next commit start or unmount), so either gc_lnum must
+ * be specially accounted for, or the current approach followed i.e. count it
+ * under 'taken_empty_lebs'.
+ */
+struct ubifs_lp_stats {
+ int empty_lebs;
+ int taken_empty_lebs;
+ int idx_lebs;
+ long long total_free;
+ long long total_dirty;
+ long long total_used;
+ long long total_dead;
+ long long total_dark;
+};
+
+struct ubifs_nnode;
+
+/**
+ * struct ubifs_cnode - LEB Properties Tree common node.
+ * @parent: parent nnode
+ * @cnext: next cnode to commit
+ * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE)
+ * @iip: index in parent
+ * @level: level in the tree (zero for pnodes, greater than zero for nnodes)
+ * @num: node number
+ */
+struct ubifs_cnode {
+ struct ubifs_nnode *parent;
+ struct ubifs_cnode *cnext;
+ unsigned long flags;
+ int iip;
+ int level;
+ int num;
+};
+
+/**
+ * struct ubifs_pnode - LEB Properties Tree leaf node.
+ * @parent: parent nnode
+ * @cnext: next cnode to commit
+ * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE)
+ * @iip: index in parent
+ * @level: level in the tree (always zero for pnodes)
+ * @num: node number
+ * @lprops: LEB properties array
+ */
+struct ubifs_pnode {
+ struct ubifs_nnode *parent;
+ struct ubifs_cnode *cnext;
+ unsigned long flags;
+ int iip;
+ int level;
+ int num;
+ struct ubifs_lprops lprops[UBIFS_LPT_FANOUT];
+};
+
+/**
+ * struct ubifs_nbranch - LEB Properties Tree internal node branch.
+ * @lnum: LEB number of child
+ * @offs: offset of child
+ * @nnode: nnode child
+ * @pnode: pnode child
+ * @cnode: cnode child
+ */
+struct ubifs_nbranch {
+ int lnum;
+ int offs;
+ union {
+ struct ubifs_nnode *nnode;
+ struct ubifs_pnode *pnode;
+ struct ubifs_cnode *cnode;
+ };
+};
+
+/**
+ * struct ubifs_nnode - LEB Properties Tree internal node.
+ * @parent: parent nnode
+ * @cnext: next cnode to commit
+ * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE)
+ * @iip: index in parent
+ * @level: level in the tree (always greater than zero for nnodes)
+ * @num: node number
+ * @nbranch: branches to child nodes
+ */
+struct ubifs_nnode {
+ struct ubifs_nnode *parent;
+ struct ubifs_cnode *cnext;
+ unsigned long flags;
+ int iip;
+ int level;
+ int num;
+ struct ubifs_nbranch nbranch[UBIFS_LPT_FANOUT];
+};
+
+/**
+ * struct ubifs_lpt_heap - heap of categorized lprops.
+ * @arr: heap array
+ * @cnt: number in heap
+ * @max_cnt: maximum number allowed in heap
+ *
+ * There are %LPROPS_HEAP_CNT heaps.
+ */
+struct ubifs_lpt_heap {
+ struct ubifs_lprops **arr;
+ int cnt;
+ int max_cnt;
+};
+
+/*
+ * Return codes for LPT scan callback function.
+ *
+ * LPT_SCAN_CONTINUE: continue scanning
+ * LPT_SCAN_ADD: add the LEB properties scanned to the tree in memory
+ * LPT_SCAN_STOP: stop scanning
+ */
+enum {
+ LPT_SCAN_CONTINUE = 0,
+ LPT_SCAN_ADD = 1,
+ LPT_SCAN_STOP = 2,
+};
+
+struct ubifs_info;
+
+/* Callback used by the 'ubifs_lpt_scan_nolock()' function */
+typedef int (*ubifs_lpt_scan_callback)(struct ubifs_info *c,
+ const struct ubifs_lprops *lprops,
+ int in_tree, void *data);
+
+/**
+ * struct ubifs_wbuf - UBIFS write-buffer.
+ * @c: UBIFS file-system description object
+ * @buf: write-buffer (of min. flash I/O unit size)
+ * @lnum: logical eraseblock number the write-buffer points to
+ * @offs: write-buffer offset in this logical eraseblock
+ * @avail: number of bytes available in the write-buffer
+ * @used: number of used bytes in the write-buffer
+ * @dtype: type of data stored in this LEB (%UBI_LONGTERM, %UBI_SHORTTERM,
+ * %UBI_UNKNOWN)
+ * @jhead: journal head the mutex belongs to (note, needed only to shut lockdep
+ * up by 'mutex_lock_nested()).
+ * @sync_callback: write-buffer synchronization callback
+ * @io_mutex: serializes write-buffer I/O
+ * @lock: serializes @buf, @lnum, @offs, @avail, @used, @next_ino and @inodes
+ * fields
+ * @timer: write-buffer timer
+ * @timeout: timer expire interval in jiffies
+ * @need_sync: it is set if its timer expired and needs sync
+ * @next_ino: points to the next position of the following inode number
+ * @inodes: stores the inode numbers of the nodes which are in wbuf
+ *
+ * The write-buffer synchronization callback is called when the write-buffer is
+ * synchronized in order to notify how much space was wasted due to
+ * write-buffer padding and how much free space is left in the LEB.
+ *
+ * Note: the fields @buf, @lnum, @offs, @avail and @used can be read under
+ * spin-lock or mutex because they are written under both mutex and spin-lock.
+ * @buf is appended to under mutex but overwritten under both mutex and
+ * spin-lock. Thus the data between @buf and @buf + @used can be read under
+ * spinlock.
+ */
+struct ubifs_wbuf {
+ struct ubifs_info *c;
+ void *buf;
+ int lnum;
+ int offs;
+ int avail;
+ int used;
+ int dtype;
+ int jhead;
+ int (*sync_callback)(struct ubifs_info *c, int lnum, int free, int pad);
+ struct mutex io_mutex;
+ spinlock_t lock;
+ struct timer_list timer;
+ int timeout;
+ int need_sync;
+ int next_ino;
+ ino_t *inodes;
+};
+
+/**
+ * struct ubifs_bud - bud logical eraseblock.
+ * @lnum: logical eraseblock number
+ * @start: where the (uncommitted) bud data starts
+ * @jhead: journal head number this bud belongs to
+ * @list: link in the list buds belonging to the same journal head
+ * @rb: link in the tree of all buds
+ */
+struct ubifs_bud {
+ int lnum;
+ int start;
+ int jhead;
+ struct list_head list;
+ struct rb_node rb;
+};
+
+/**
+ * struct ubifs_jhead - journal head.
+ * @wbuf: head's write-buffer
+ * @buds_list: list of bud LEBs belonging to this journal head
+ *
+ * Note, the @buds list is protected by the @c->buds_lock.
+ */
+struct ubifs_jhead {
+ struct ubifs_wbuf wbuf;
+ struct list_head buds_list;
+};
+
+/**
+ * struct ubifs_zbranch - key/coordinate/length branch stored in znodes.
+ * @key: key
+ * @znode: znode address in memory
+ * @lnum: LEB number of the indexing node
+ * @offs: offset of the indexing node within @lnum
+ * @len: target node length
+ */
+struct ubifs_zbranch {
+ union ubifs_key key;
+ union {
+ struct ubifs_znode *znode;
+ void *leaf;
+ };
+ int lnum;
+ int offs;
+ int len;
+};
+
+/**
+ * struct ubifs_znode - in-memory representation of an indexing node.
+ * @parent: parent znode or NULL if it is the root
+ * @cnext: next znode to commit
+ * @flags: znode flags (%DIRTY_ZNODE, %COW_ZNODE or %OBSOLETE_ZNODE)
+ * @time: last access time (seconds)
+ * @level: level of the entry in the TNC tree
+ * @child_cnt: count of child znodes
+ * @iip: index in parent's zbranch array
+ * @alt: lower bound of key range has altered i.e. child inserted at slot 0
+ * @lnum: LEB number of the corresponding indexing node
+ * @offs: offset of the corresponding indexing node
+ * @len: length of the corresponding indexing node
+ * @zbranch: array of znode branches (@c->fanout elements)
+ */
+struct ubifs_znode {
+ struct ubifs_znode *parent;
+ struct ubifs_znode *cnext;
+ unsigned long flags;
+ unsigned long time;
+ int level;
+ int child_cnt;
+ int iip;
+ int alt;
+#ifdef CONFIG_UBIFS_FS_DEBUG
+ int lnum, offs, len;
+#endif
+ struct ubifs_zbranch zbranch[];
+};
+
+/**
+ * struct ubifs_node_range - node length range description data structure.
+ * @len: fixed node length
+ * @min_len: minimum possible node length
+ * @max_len: maximum possible node length
+ *
+ * If @max_len is %0, the node has fixed length @len.
+ */
+struct ubifs_node_range {
+ union {
+ int len;
+ int min_len;
+ };
+ int max_len;
+};
+
+/**
+ * struct ubifs_compressor - UBIFS compressor description structure.
+ * @compr_type: compressor type (%UBIFS_COMPR_LZO, etc)
+ * @cc: cryptoapi compressor handle
+ * @comp_mutex: mutex used during compression
+ * @decomp_mutex: mutex used during decompression
+ * @name: compressor name
+ * @capi_name: cryptoapi compressor name
+ */
+struct ubifs_compressor {
+ int compr_type;
+ struct crypto_comp *cc;
+ struct mutex *comp_mutex;
+ struct mutex *decomp_mutex;
+ const char *name;
+ const char *capi_name;
+};
+
+/**
+ * struct ubifs_budget_req - budget requirements of an operation.
+ *
+ * @fast: non-zero if the budgeting should try to aquire budget quickly and
+ * should not try to call write-back
+ * @recalculate: non-zero if @idx_growth, @data_growth, and @dd_growth fields
+ * have to be re-calculated
+ * @new_page: non-zero if the operation adds a new page
+ * @dirtied_page: non-zero if the operation makes a page dirty
+ * @new_dent: non-zero if the operation adds a new directory entry
+ * @mod_dent: non-zero if the operation removes or modifies an existing
+ * directory entry
+ * @new_ino: non-zero if the operation adds a new inode
+ * @new_ino_d: now much data newly created inode contains
+ * @dirtied_ino: how many inodes the operation makes dirty
+ * @dirtied_ino_d: now much data dirtied inode contains
+ * @idx_growth: how much the index will supposedly grow
+ * @data_growth: how much new data the operation will supposedly add
+ * @dd_growth: how much data that makes other data dirty the operation will
+ * supposedly add
+ *
+ * @idx_growth, @data_growth and @dd_growth are not used in budget request. The
+ * budgeting subsystem caches index and data growth values there to avoid
+ * re-calculating them when the budget is released. However, if @idx_growth is
+ * %-1, it is calculated by the release function using other fields.
+ *
+ * An inode may contain 4KiB of data at max., thus the widths of @new_ino_d
+ * is 13 bits, and @dirtied_ino_d - 15, because up to 4 inodes may be made
+ * dirty by the re-name operation.
+ */
+struct ubifs_budget_req {
+ unsigned int fast:1;
+ unsigned int recalculate:1;
+ unsigned int new_page:1;
+ unsigned int dirtied_page:1;
+ unsigned int new_dent:1;
+ unsigned int mod_dent:1;
+ unsigned int new_ino:1;
+ unsigned int new_ino_d:13;
+#ifndef UBIFS_DEBUG
+ unsigned int dirtied_ino:4;
+ unsigned int dirtied_ino_d:15;
+#else
+ /* Not bit-fields to check for overflows */
+ unsigned int dirtied_ino;
+ unsigned int dirtied_ino_d;
+#endif
+ int idx_growth;
+ int data_growth;
+ int dd_growth;
+};
+
+/**
+ * struct ubifs_orphan - stores the inode number of an orphan.
+ * @rb: rb-tree node of rb-tree of orphans sorted by inode number
+ * @list: list head of list of orphans in order added
+ * @new_list: list head of list of orphans added since the last commit
+ * @cnext: next orphan to commit
+ * @dnext: next orphan to delete
+ * @inum: inode number
+ * @new: %1 => added since the last commit, otherwise %0
+ */
+struct ubifs_orphan {
+ struct rb_node rb;
+ struct list_head list;
+ struct list_head new_list;
+ struct ubifs_orphan *cnext;
+ struct ubifs_orphan *dnext;
+ ino_t inum;
+ int new;
+};
+
+/**
+ * struct ubifs_mount_opts - UBIFS-specific mount options information.
+ * @unmount_mode: selected unmount mode (%0 default, %1 normal, %2 fast)
+ */
+struct ubifs_mount_opts {
+ unsigned int unmount_mode:2;
+};
+
+/**
+ * struct ubifs_info - UBIFS file-system description data structure
+ * (per-superblock).
+ * @vfs_sb: VFS @struct super_block object
+ * @bdi: backing device info object to make VFS happy and disable readahead
+ *
+ * @highest_inum: highest used inode number
+ * @vfs_gen: VFS inode generation counter
+ * @max_sqnum: current global sequence number
+ * @cmt_no: commit number (last successfully completed commit)
+ * @cnt_lock: protects @highest_inum, @vfs_gen, and @max_sqnum counters
+ * @fmt_version: UBIFS on-flash format version
+ * @uuid: UUID from super block
+ *
+ * @lhead_lnum: log head logical eraseblock number
+ * @lhead_offs: log head offset
+ * @ltail_lnum: log tail logical eraseblock number (offset is always 0)
+ * @log_mutex: protects the log, @lhead_lnum, @lhead_offs, @ltail_lnum, and
+ * @bud_bytes
+ * @min_log_bytes: minimum required number of bytes in the log
+ * @cmt_bud_bytes: used during commit to temporarily amount of bytes in
+ * committed buds
+ *
+ * @buds: tree of all buds indexed by bud LEB number
+ * @bud_bytes: how many bytes of flash is used by buds
+ * @buds_lock: protects the @buds tree, @bud_bytes, and per-journal head bud
+ * lists
+ * @jhead_cnt: count of journal heads
+ * @jheads: journal heads (head zero is base head)
+ * @max_bud_bytes: maximum number of bytes allowed in buds
+ * @bg_bud_bytes: number of bud bytes when background commit is initiated
+ * @old_buds: buds to be released after commit ends
+ * @max_bud_cnt: maximum number of buds
+ *
+ * @commit_sem: synchronizes committer with other processes
+ * @cmt_state: commit state
+ * @cs_lock: commit state lock
+ * @cmt_wq: wait queue to sleep on if the log is full and a commit is running
+ * @fast_unmount: do not run journal commit before un-mounting
+ * @big_lpt: flag that LPT is too big to write whole during commit
+ * @check_lpt_free: flag that indicates LPT GC may be needed
+ * @nospace: non-zero if the file-system does not have flash space (used as
+ * optimization)
+ * @nospace_rp: the same as @nospace, but additionally means that even reserved
+ * pool is full
+ *
+ * @tnc_mutex: protects the Tree Node Cache (TNC), @zroot, @cnext, @enext, and
+ * @calc_idx_sz
+ * @zroot: zbranch which points to the root index node and znode
+ * @cnext: next znode to commit
+ * @enext: next znode to commit to empty space
+ * @gap_lebs: array of LEBs used by the in-gaps commit method
+ * @cbuf: commit buffer
+ * @ileb_buf: buffer for commit in-the-gaps method
+ * @ileb_len: length of data in ileb_buf
+ * @ihead_lnum: LEB number of index head
+ * @ihead_offs: offset of index head
+ * @ilebs: pre-allocated index LEBs
+ * @ileb_cnt: number of pre-allocated index LEBs
+ * @ileb_nxt: next pre-allocated index LEBs
+ * @old_idx: tree of index nodes obsoleted since the last commit start
+ * @bottom_up_buf: a buffer which is used by 'dirty_cow_bottom_up()' in tnc.c
+ * @new_ihead_lnum: used by debugging to check ihead_lnum
+ * @new_ihead_offs: used by debugging to check ihead_offs
+ *
+ * @mst_node: master node
+ * @mst_offs: offset of valid master node
+ * @mst_mutex: protects the master node area, @mst_node, and @mst_offs
+ *
+ * @log_lebs: number of logical eraseblocks in the log
+ * @log_bytes: log size in bytes
+ * @log_last: last LEB of the log
+ * @lpt_lebs: number of LEBs used for lprops table
+ * @lpt_first: first LEB of the lprops table area
+ * @lpt_last: last LEB of the lprops table area
+ * @orph_lebs: number of LEBs used for the orphan area
+ * @orph_first: first LEB of the orphan area
+ * @orph_last: last LEB of the orphan area
+ * @main_lebs: count of LEBs in the main area
+ * @main_first: first LEB of the main area
+ * @main_bytes: main area size in bytes
+ * @default_compr: default compression algorithm (%UBIFS_COMPR_LZO, etc)
+ *
+ * @key_hash_type: type of the key hash
+ * @key_hash: direntry key hash function
+ * @key_fmt: key format
+ * @key_len: key length
+ * @fanout: fanout of the index tree (number of links per indexing node)
+ *
+ * @min_io_size: minimal input/output unit size
+ * @min_io_shift: number of bits in @min_io_size minus one
+ * @leb_size: logical eraseblock size in bytes
+ * @half_leb_size: half LEB size
+ * @leb_cnt: count of logical eraseblocks
+ * @max_leb_cnt: maximum count of logical eraseblocks
+ * @old_leb_cnt: count of logical eraseblocks before re-size
+ * @ro_media: the underlying UBI volume is read-only
+ *
+ * @dirty_pg_cnt: number of dirty pages (not used)
+ * @dirty_zn_cnt: number of dirty znodes
+ * @clean_zn_cnt: number of clean znodes
+ *
+ * @budg_idx_growth: amount of bytes budgeted for index growth
+ * @budg_data_growth: amount of bytes budgeted for cached data
+ * @budg_dd_growth: amount of bytes budgeted for cached data that will make
+ * other data dirty
+ * @budg_uncommitted_idx: amount of bytes were budgeted for growth of the index,
+ * but which still have to be taken into account because
+ * the index has not been committed so far
+ * @space_lock: protects @budg_idx_growth, @budg_data_growth, @budg_dd_growth,
+ * @budg_uncommited_idx, @min_idx_lebs, @old_idx_sz, and @lst;
+ * @min_idx_lebs: minimum number of LEBs required for the index
+ * @old_idx_sz: size of index on flash
+ * @calc_idx_sz: temporary variable which is used to calculate new index size
+ * (contains accurate new index size at end of TNC commit start)
+ * @lst: lprops statistics
+ *
+ * @page_budget: budget for a page
+ * @inode_budget: budget for an inode
+ * @dent_budget: budget for a directory entry
+ *
+ * @ref_node_alsz: size of the LEB reference node aligned to the min. flash
+ * I/O unit
+ * @mst_node_alsz: master node aligned size
+ * @min_idx_node_sz: minimum indexing node aligned on 8-bytes boundary
+ * @max_idx_node_sz: maximum indexing node aligned on 8-bytes boundary
+ * @max_inode_sz: maximum possible inode size in bytes
+ * @max_znode_sz: size of znode in bytes
+ * @dead_wm: LEB dead space watermark
+ * @dark_wm: LEB dark space watermark
+ * @block_cnt: count of 4KiB blocks on the FS
+ *
+ * @ranges: UBIFS node length ranges
+ * @ubi: UBI volume descriptor
+ * @di: UBI device information
+ * @vi: UBI volume information
+ *
+ * @orph_tree: rb-tree of orphan inode numbers
+ * @orph_list: list of orphan inode numbers in order added
+ * @orph_new: list of orphan inode numbers added since last commit
+ * @orph_cnext: next orphan to commit
+ * @orph_dnext: next orphan to delete
+ * @orphan_lock: lock for orph_tree and orph_new
+ * @orph_buf: buffer for orphan nodes
+ * @new_orphans: number of orphans since last commit
+ * @cmt_orphans: number of orphans being committed
+ * @tot_orphans: number of orphans in the rb_tree
+ * @max_orphans: maximum number of orphans allowed
+ * @ohead_lnum: orphan head LEB number
+ * @ohead_offs: orphan head offset
+ * @no_orphs: non-zero if there are no orphans
+ *
+ * @bgt: UBIFS background thread
+ * @bgt_name: background thread name
+ * @need_bgt: if background thread should run
+ * @need_wbuf_sync: if write-buffers have to be synchronized
+ *
+ * @gc_lnum: LEB number used for garbage collection
+ * @sbuf: a buffer of LEB size used by GC and replay for scanning
+ * @idx_gc: list of index LEBs that have been garbage collected
+ * @idx_gc_cnt: number of elements on the idx_gc list
+ *
+ * @infos_list: links all 'ubifs_info' objects
+ * @umount_mutex: serializes shrinker and un-mount
+ * @shrinker_run_no: shrinker run number
+ *
+ * @space_bits: number of bits needed to record free or dirty space
+ * @lpt_lnum_bits: number of bits needed to record a LEB number in the LPT
+ * @lpt_offs_bits: number of bits needed to record an offset in the LPT
+ * @lpt_spc_bits: number of bits needed to space in the LPT
+ * @pcnt_bits: number of bits needed to record pnode or nnode number
+ * @lnum_bits: number of bits needed to record LEB number
+ * @nnode_sz: size of on-flash nnode
+ * @pnode_sz: size of on-flash pnode
+ * @ltab_sz: size of on-flash LPT lprops table
+ * @lsave_sz: size of on-flash LPT save table
+ * @pnode_cnt: number of pnodes
+ * @nnode_cnt: number of nnodes
+ * @lpt_hght: height of the LPT
+ * @pnodes_have: number of pnodes in memory
+ *
+ * @lp_mutex: protects lprops table and all the other lprops-related fields
+ * @lpt_lnum: LEB number of the root nnode of the LPT
+ * @lpt_offs: offset of the root nnode of the LPT
+ * @nhead_lnum: LEB number of LPT head
+ * @nhead_offs: offset of LPT head
+ * @lpt_drty_flgs: dirty flags for LPT special nodes e.g. ltab
+ * @dirty_nn_cnt: number of dirty nnodes
+ * @dirty_pn_cnt: number of dirty pnodes
+ * @lpt_sz: LPT size
+ * @lpt_nod_buf: buffer for an on-flash nnode or pnode
+ * @lpt_buf: buffer of LEB size used by LPT
+ * @nroot: address in memory of the root nnode of the LPT
+ * @lpt_cnext: next LPT node to commit
+ * @lpt_heap: array of heaps of categorized lprops
+ * @dirty_idx: a (reverse sorted) copy of the LPROPS_DIRTY_IDX heap as at
+ * previous commit start
+ * @uncat_list: list of un-categorized LEBs
+ * @empty_list: list of empty LEBs
+ * @freeable_list: list of freeable non-index LEBs (free + dirty == leb_size)
+ * @frdi_idx_list: list of freeable index LEBs (free + dirty == leb_size)
+ * @freeable_cnt: number of freeable LEBs in @freeable_list
+ *
+ * @ltab_lnum: LEB number of LPT's own lprops table
+ * @ltab_offs: offset of LPT's own lprops table
+ * @ltab: LPT's own lprops table
+ * @ltab_cmt: LPT's own lprops table (commit copy)
+ * @lsave_cnt: number of LEB numbers in LPT's save table
+ * @lsave_lnum: LEB number of LPT's save table
+ * @lsave_offs: offset of LPT's save table
+ * @lsave: LPT's save table
+ * @lscan_lnum: LEB number of last LPT scan
+ *
+ * @rp_size: size of the reserved pool in bytes
+ * @report_rp_size: size of the reserved pool reported to user-space
+ * @rp_uid: reserved pool user ID
+ * @rp_gid: reserved pool group ID
+ *
+ * @empty: if the UBI device is empty
+ * @replay_tree: temporary tree used during journal replay
+ * @replay_list: temporary list used during journal replay
+ * @replay_buds: list of buds to replay
+ * @cs_sqnum: sequence number of first node in the log (commit start node)
+ * @replay_sqnum: sequence number of node currently being replayed
+ * @need_recovery: file-system needs recovery
+ * @replaying: set to %1 during journal replay
+ * @unclean_leb_list: LEBs to recover when mounting ro to rw
+ * @rcvrd_mst_node: recovered master node to write when mounting ro to rw
+ * @size_tree: inode size information for recovery
+ * @remounting_rw: set while remounting from ro to rw (sb flags have MS_RDONLY)
+ * @mount_opts: UBIFS-specific mount options
+ *
+ * @dbg_buf: a buffer of LEB size used for debugging purposes
+ * @old_zroot: old index root - used by 'dbg_check_old_index()'
+ * @old_zroot_level: old index root level - used by 'dbg_check_old_index()'
+ * @old_zroot_sqnum: old index root sqnum - used by 'dbg_check_old_index()'
+ * @failure_mode: failure mode for recovery testing
+ * @fail_delay: 0=>don't delay, 1=>delay a time, 2=>delay a number of calls
+ * @fail_timeout: time in jiffies when delay of failure mode expires
+ * @fail_cnt: current number of calls to failure mode I/O functions
+ * @fail_cnt_max: number of calls by which to delay failure mode
+ */
+struct ubifs_info {
+ struct super_block *vfs_sb;
+ struct backing_dev_info bdi;
+
+ ino_t highest_inum;
+ unsigned int vfs_gen;
+ unsigned long long max_sqnum;
+ unsigned long long cmt_no;
+ spinlock_t cnt_lock;
+ int fmt_version;
+ unsigned char uuid[16];
+
+ int lhead_lnum;
+ int lhead_offs;
+ int ltail_lnum;
+ struct mutex log_mutex;
+ int min_log_bytes;
+ long long cmt_bud_bytes;
+
+ struct rb_root buds;
+ long long bud_bytes;
+ spinlock_t buds_lock;
+ int jhead_cnt;
+ struct ubifs_jhead *jheads;
+ long long max_bud_bytes;
+ long long bg_bud_bytes;
+ struct list_head old_buds;
+ int max_bud_cnt;
+
+ struct rw_semaphore commit_sem;
+ int cmt_state;
+ spinlock_t cs_lock;
+ wait_queue_head_t cmt_wq;
+ unsigned int fast_unmount:1;
+ unsigned int big_lpt:1;
+ unsigned int check_lpt_free:1;
+ unsigned int nospace:1;
+ unsigned int nospace_rp:1;
+
+ struct mutex tnc_mutex;
+ struct ubifs_zbranch zroot;
+ struct ubifs_znode *cnext;
+ struct ubifs_znode *enext;
+ int *gap_lebs;
+ void *cbuf;
+ void *ileb_buf;
+ int ileb_len;
+ int ihead_lnum;
+ int ihead_offs;
+ int *ilebs;
+ int ileb_cnt;
+ int ileb_nxt;
+ struct rb_root old_idx;
+ int *bottom_up_buf;
+#ifdef CONFIG_UBIFS_FS_DEBUG
+ int new_ihead_lnum;
+ int new_ihead_offs;
+#endif
+
+ struct ubifs_mst_node *mst_node;
+ int mst_offs;
+ struct mutex mst_mutex;
+
+ int log_lebs;
+ long long log_bytes;
+ int log_last;
+ int lpt_lebs;
+ int lpt_first;
+ int lpt_last;
+ int orph_lebs;
+ int orph_first;
+ int orph_last;
+ int main_lebs;
+ int main_first;
+ long long main_bytes;
+ int default_compr;
+
+ uint8_t key_hash_type;
+ uint32_t (*key_hash)(const char *str, int len);
+ int key_fmt;
+ int key_len;
+ int fanout;
+
+ int min_io_size;
+ int min_io_shift;
+ int leb_size;
+ int half_leb_size;
+ int leb_cnt;
+ int max_leb_cnt;
+ int old_leb_cnt;
+ int ro_media;
+
+ atomic_long_t dirty_pg_cnt;
+ atomic_long_t dirty_zn_cnt;
+ atomic_long_t clean_zn_cnt;
+
+ long long budg_idx_growth;
+ long long budg_data_growth;
+ long long budg_dd_growth;
+ long long budg_uncommitted_idx;
+ spinlock_t space_lock;
+ int min_idx_lebs;
+ unsigned long long old_idx_sz;
+ unsigned long long calc_idx_sz;
+ struct ubifs_lp_stats lst;
+
+ int page_budget;
+ int inode_budget;
+ int dent_budget;
+
+ int ref_node_alsz;
+ int mst_node_alsz;
+ int min_idx_node_sz;
+ int max_idx_node_sz;
+ long long max_inode_sz;
+ int max_znode_sz;
+ int dead_wm;
+ int dark_wm;
+ int block_cnt;
+
+ struct ubifs_node_range ranges[UBIFS_NODE_TYPES_CNT];
+ struct ubi_volume_desc *ubi;
+ struct ubi_device_info di;
+ struct ubi_volume_info vi;
+
+ struct rb_root orph_tree;
+ struct list_head orph_list;
+ struct list_head orph_new;
+ struct ubifs_orphan *orph_cnext;
+ struct ubifs_orphan *orph_dnext;
+ spinlock_t orphan_lock;
+ void *orph_buf;
+ int new_orphans;
+ int cmt_orphans;
+ int tot_orphans;
+ int max_orphans;
+ int ohead_lnum;
+ int ohead_offs;
+ int no_orphs;
+
+ struct task_struct *bgt;
+ char bgt_name[sizeof(BGT_NAME_PATTERN) + 9];
+ int need_bgt;
+ int need_wbuf_sync;
+
+ int gc_lnum;
+ void *sbuf;
+ struct list_head idx_gc;
+ int idx_gc_cnt;
+
+ struct list_head infos_list;
+ struct mutex umount_mutex;
+ unsigned int shrinker_run_no;
+
+ int space_bits;
+ int lpt_lnum_bits;
+ int lpt_offs_bits;
+ int lpt_spc_bits;
+ int pcnt_bits;
+ int lnum_bits;
+ int nnode_sz;
+ int pnode_sz;
+ int ltab_sz;
+ int lsave_sz;
+ int pnode_cnt;
+ int nnode_cnt;
+ int lpt_hght;
+ int pnodes_have;
+
+ struct mutex lp_mutex;
+ int lpt_lnum;
+ int lpt_offs;
+ int nhead_lnum;
+ int nhead_offs;
+ int lpt_drty_flgs;
+ int dirty_nn_cnt;
+ int dirty_pn_cnt;
+ long long lpt_sz;
+ void *lpt_nod_buf;
+ void *lpt_buf;
+ struct ubifs_nnode *nroot;
+ struct ubifs_cnode *lpt_cnext;
+ struct ubifs_lpt_heap lpt_heap[LPROPS_HEAP_CNT];
+ struct ubifs_lpt_heap dirty_idx;
+ struct list_head uncat_list;
+ struct list_head empty_list;
+ struct list_head freeable_list;
+ struct list_head frdi_idx_list;
+ int freeable_cnt;
+
+ int ltab_lnum;
+ int ltab_offs;
+ struct ubifs_lpt_lprops *ltab;
+ struct ubifs_lpt_lprops *ltab_cmt;
+ int lsave_cnt;
+ int lsave_lnum;
+ int lsave_offs;
+ int *lsave;
+ int lscan_lnum;
+
+ long long rp_size;
+ long long report_rp_size;
+ uid_t rp_uid;
+ gid_t rp_gid;
+
+ /* The below fields are used only during mounting and re-mounting */
+ int empty;
+ struct rb_root replay_tree;
+ struct list_head replay_list;
+ struct list_head replay_buds;
+ unsigned long long cs_sqnum;
+ unsigned long long replay_sqnum;
+ int need_recovery;
+ int replaying;
+ struct list_head unclean_leb_list;
+ struct ubifs_mst_node *rcvrd_mst_node;
+ struct rb_root size_tree;
+ int remounting_rw;
+ struct ubifs_mount_opts mount_opts;
+
+#ifdef CONFIG_UBIFS_FS_DEBUG
+ void *dbg_buf;
+ struct ubifs_zbranch old_zroot;
+ int old_zroot_level;
+ unsigned long long old_zroot_sqnum;
+ int failure_mode;
+ int fail_delay;
+ unsigned long fail_timeout;
+ unsigned int fail_cnt;
+ unsigned int fail_cnt_max;
+#endif
+};
+
+extern struct list_head ubifs_infos;
+extern spinlock_t ubifs_infos_lock;
+extern atomic_long_t ubifs_clean_zn_cnt;
+extern struct kmem_cache *ubifs_inode_slab;
+extern struct super_operations ubifs_super_operations;
+extern struct address_space_operations ubifs_file_address_operations;
+extern struct file_operations ubifs_file_operations;
+extern struct inode_operations ubifs_file_inode_operations;
+extern struct file_operations ubifs_dir_operations;
+extern struct inode_operations ubifs_dir_inode_operations;
+extern struct inode_operations ubifs_symlink_inode_operations;
+extern struct backing_dev_info ubifs_backing_dev_info;
+extern struct ubifs_compressor *ubifs_compressors[UBIFS_COMPR_TYPES_CNT];
+
+/* io.c */
+int ubifs_wbuf_write_nolock(struct ubifs_wbuf *wbuf, void *buf, int len);
+int ubifs_wbuf_seek_nolock(struct ubifs_wbuf *wbuf, int lnum, int offs,
+ int dtype);
+int ubifs_wbuf_init(struct ubifs_info *c, struct ubifs_wbuf *wbuf);
+int ubifs_read_node(const struct ubifs_info *c, void *buf, int type, int len,
+ int lnum, int offs);
+int ubifs_read_node_wbuf(struct ubifs_wbuf *wbuf, void *buf, int type, int len,
+ int lnum, int offs);
+int ubifs_write_node(struct ubifs_info *c, void *node, int len, int lnum,
+ int offs, int dtype);
+int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum,
+ int offs, int quiet);
+void ubifs_prepare_node(struct ubifs_info *c, void *buf, int len, int pad);
+void ubifs_prep_grp_node(struct ubifs_info *c, void *node, int len, int last);
+int ubifs_io_init(struct ubifs_info *c);
+void ubifs_pad(const struct ubifs_info *c, void *buf, int pad);
+int ubifs_wbuf_sync_nolock(struct ubifs_wbuf *wbuf);
+int ubifs_bg_wbufs_sync(struct ubifs_info *c);
+void ubifs_wbuf_add_ino_nolock(struct ubifs_wbuf *wbuf, ino_t inum);
+int ubifs_sync_wbufs_by_inode(struct ubifs_info *c, struct inode *inode);
+
+/* scan.c */
+struct ubifs_scan_leb *ubifs_scan(const struct ubifs_info *c, int lnum,
+ int offs, void *sbuf);
+void ubifs_scan_destroy(struct ubifs_scan_leb *sleb);
+int ubifs_scan_a_node(const struct ubifs_info *c, void *buf, int len, int lnum,
+ int offs, int quiet);
+struct ubifs_scan_leb *ubifs_start_scan(const struct ubifs_info *c, int lnum,
+ int offs, void *sbuf);
+void ubifs_end_scan(const struct ubifs_info *c, struct ubifs_scan_leb *sleb,
+ int lnum, int offs);
+int ubifs_add_snod(const struct ubifs_info *c, struct ubifs_scan_leb *sleb,
+ void *buf, int offs);
+void ubifs_scanned_corruption(const struct ubifs_info *c, int lnum, int offs,
+ void *buf);
+
+/* log.c */
+void ubifs_add_bud(struct ubifs_info *c, struct ubifs_bud *bud);
+void ubifs_create_buds_lists(struct ubifs_info *c);
+int ubifs_add_bud_to_log(struct ubifs_info *c, int jhead, int lnum, int offs);
+struct ubifs_bud *ubifs_search_bud(struct ubifs_info *c, int lnum);
+struct ubifs_wbuf *ubifs_get_wbuf(struct ubifs_info *c, int lnum);
+int ubifs_log_start_commit(struct ubifs_info *c, int *ltail_lnum);
+int ubifs_log_end_commit(struct ubifs_info *c, int new_ltail_lnum);
+int ubifs_log_post_commit(struct ubifs_info *c, int old_ltail_lnum);
+int ubifs_consolidate_log(struct ubifs_info *c);
+
+/* journal.c */
+int ubifs_jnl_update(struct ubifs_info *c, const struct inode *dir,
+ const struct qstr *nm, const struct inode *inode,
+ int deletion, int xent);
+int ubifs_jnl_write_data(struct ubifs_info *c, const struct inode *inode,
+ const union ubifs_key *key, const void *buf, int len);
+int ubifs_jnl_write_inode(struct ubifs_info *c, const struct inode *inode,
+ int last_reference);
+int ubifs_jnl_rename(struct ubifs_info *c, const struct inode *old_dir,
+ const struct dentry *old_dentry,
+ const struct inode *new_dir,
+ const struct dentry *new_dentry, int sync);
+int ubifs_jnl_truncate(struct ubifs_info *c, const struct inode *inode,
+ loff_t old_size, loff_t new_size);
+int ubifs_jnl_delete_xattr(struct ubifs_info *c, const struct inode *host,
+ const struct inode *inode, const struct qstr *nm);
+int ubifs_jnl_change_xattr(struct ubifs_info *c, const struct inode *inode1,
+ const struct inode *inode2);
+
+/* budget.c */
+int ubifs_budget_space(struct ubifs_info *c, struct ubifs_budget_req *req);
+void ubifs_release_budget(struct ubifs_info *c, struct ubifs_budget_req *req);
+void ubifs_release_dirty_inode_budget(struct ubifs_info *c,
+ struct ubifs_inode *ui);
+int ubifs_budget_inode_op(struct ubifs_info *c, struct inode *inode,
+ struct ubifs_budget_req *req);
+void ubifs_release_ino_dirty(struct ubifs_info *c, struct inode *inode,
+ struct ubifs_budget_req *req);
+void ubifs_cancel_ino_op(struct ubifs_info *c, struct inode *inode,
+ struct ubifs_budget_req *req);
+long long ubifs_budg_get_free_space(struct ubifs_info *c);
+int ubifs_calc_min_idx_lebs(struct ubifs_info *c);
+void ubifs_convert_page_budget(struct ubifs_info *c);
+long long ubifs_calc_available(const struct ubifs_info *c, int min_idx_lebs);
+
+/* find.c */
+int ubifs_find_free_space(struct ubifs_info *c, int min_space, int *free,
+ int squeeze);
+int ubifs_find_free_leb_for_idx(struct ubifs_info *c);
+int ubifs_find_dirty_leb(struct ubifs_info *c, struct ubifs_lprops *ret_lp,
+ int min_space, int pick_free);
+int ubifs_find_dirty_idx_leb(struct ubifs_info *c);
+int ubifs_save_dirty_idx_lnums(struct ubifs_info *c);
+
+/* tnc.c */
+int ubifs_lookup_level0(struct ubifs_info *c, const union ubifs_key *key,
+ struct ubifs_znode **zn, int *n);
+int ubifs_tnc_lookup(struct ubifs_info *c, const union ubifs_key *key,
+ void *node);
+int ubifs_tnc_lookup_nm(struct ubifs_info *c, const union ubifs_key *key,
+ void *node, const struct qstr *nm);
+int ubifs_tnc_locate(struct ubifs_info *c, const union ubifs_key *key,
+ void *node, int *lnum, int *offs);
+int ubifs_tnc_add(struct ubifs_info *c, const union ubifs_key *key, int lnum,
+ int offs, int len);
+int ubifs_tnc_replace(struct ubifs_info *c, const union ubifs_key *key,
+ int old_lnum, int old_offs, int lnum, int offs, int len);
+int ubifs_tnc_add_nm(struct ubifs_info *c, const union ubifs_key *key,
+ int lnum, int offs, int len, const struct qstr *nm);
+int ubifs_tnc_remove(struct ubifs_info *c, const union ubifs_key *key);
+int ubifs_tnc_remove_nm(struct ubifs_info *c, const union ubifs_key *key,
+ const struct qstr *nm);
+int ubifs_tnc_remove_range(struct ubifs_info *c, union ubifs_key *from_key,
+ union ubifs_key *to_key);
+int ubifs_tnc_remove_ino(struct ubifs_info *c, ino_t inum);
+struct ubifs_dent_node *ubifs_tnc_next_ent(struct ubifs_info *c,
+ union ubifs_key *key,
+ const struct qstr *nm);
+void ubifs_tnc_close(struct ubifs_info *c);
+int ubifs_tnc_has_node(struct ubifs_info *c, union ubifs_key *key, int level,
+ int lnum, int offs, int is_idx);
+int ubifs_dirty_idx_node(struct ubifs_info *c, union ubifs_key *key, int level,
+ int lnum, int offs);
+/* Shared by tnc.c for tnc_commit.c */
+void destroy_old_idx(struct ubifs_info *c);
+int is_idx_node_in_tnc(struct ubifs_info *c, union ubifs_key *key, int level,
+ int lnum, int offs);
+int insert_old_idx_znode(struct ubifs_info *c, struct ubifs_znode *znode);
+
+/* tnc_misc.c */
+struct ubifs_znode *ubifs_tnc_levelorder_next(struct ubifs_znode *zr,
+ struct ubifs_znode *znode);
+int ubifs_search_zbranch(const struct ubifs_info *c,
+ const struct ubifs_znode *znode,
+ const union ubifs_key *key, int *n);
+struct ubifs_znode *ubifs_tnc_postorder_first(struct ubifs_znode *znode);
+struct ubifs_znode *ubifs_tnc_postorder_next(struct ubifs_znode *znode);
+long ubifs_destroy_tnc_subtree(struct ubifs_znode *zr);
+struct ubifs_znode *ubifs_load_znode(struct ubifs_info *c,
+ struct ubifs_zbranch *zbr,
+ struct ubifs_znode *parent, int iip);
+int ubifs_tnc_read_node(struct ubifs_info *c, struct ubifs_zbranch *zbr,
+ void *node);
+
+/* tnc_commit.c */
+int ubifs_tnc_start_commit(struct ubifs_info *c, struct ubifs_zbranch *zroot);
+int ubifs_tnc_end_commit(struct ubifs_info *c);
+
+/* shrinker.c */
+int ubifs_shrinker(int nr_to_scan, gfp_t gfp_mask);
+
+/* commit.c */
+int ubifs_bg_thread(void *info);
+void ubifs_commit_required(struct ubifs_info *c);
+void ubifs_request_bg_commit(struct ubifs_info *c);
+int ubifs_run_commit(struct ubifs_info *c);
+void ubifs_recovery_commit(struct ubifs_info *c);
+int ubifs_gc_should_commit(struct ubifs_info *c);
+void ubifs_wait_for_commit(struct ubifs_info *c);
+
+/* master.c */
+int ubifs_read_master(struct ubifs_info *c);
+int ubifs_write_master(struct ubifs_info *c);
+
+/* sb.c */
+int ubifs_read_superblock(struct ubifs_info *c);
+struct ubifs_sb_node *ubifs_read_sb_node(struct ubifs_info *c);
+int ubifs_write_sb_node(struct ubifs_info *c, struct ubifs_sb_node *sup);
+
+/* replay.c */
+int ubifs_validate_entry(struct ubifs_info *c,
+ const struct ubifs_dent_node *dent);
+int ubifs_replay_journal(struct ubifs_info *c);
+
+/* gc.c */
+int ubifs_garbage_collect(struct ubifs_info *c, int anyway);
+int ubifs_gc_start_commit(struct ubifs_info *c);
+int ubifs_gc_end_commit(struct ubifs_info *c);
+void ubifs_destroy_idx_gc(struct ubifs_info *c);
+int ubifs_get_idx_gc_leb(struct ubifs_info *c);
+int ubifs_garbage_collect_leb(struct ubifs_info *c, struct ubifs_lprops *lp);
+
+/* orphan.c */
+int ubifs_add_orphan(struct ubifs_info *c, ino_t inum);
+void ubifs_delete_orphan(struct ubifs_info *c, ino_t inum);
+int ubifs_orphan_start_commit(struct ubifs_info *c);
+int ubifs_orphan_end_commit(struct ubifs_info *c);
+int ubifs_mount_orphans(struct ubifs_info *c, int unclean, int read_only);
+
+/* lpt.c */
+int ubifs_calc_lpt_geom(struct ubifs_info *c);
+int ubifs_create_dflt_lpt(struct ubifs_info *c, int *main_lebs, int lpt_first,
+ int *lpt_lebs, int *big_lpt);
+int ubifs_lpt_init(struct ubifs_info *c, int rd, int wr);
+struct ubifs_lprops *ubifs_lpt_lookup(struct ubifs_info *c, int lnum);
+struct ubifs_lprops *ubifs_lpt_lookup_dirty(struct ubifs_info *c, int lnum);
+int ubifs_lpt_scan_nolock(struct ubifs_info *c, int start_lnum, int end_lnum,
+ ubifs_lpt_scan_callback scan_cb, void *data);
+
+/* Shared by lpt.c for lpt_commit.c */
+void ubifs_pack_lsave(struct ubifs_info *c, void *buf, int *lsave);
+void ubifs_pack_ltab(struct ubifs_info *c, void *buf,
+ struct ubifs_lpt_lprops *ltab);
+void ubifs_pack_pnode(struct ubifs_info *c, void *buf,
+ struct ubifs_pnode *pnode);
+void ubifs_pack_nnode(struct ubifs_info *c, void *buf,
+ struct ubifs_nnode *nnode);
+struct ubifs_pnode *ubifs_get_pnode(struct ubifs_info *c,
+ struct ubifs_nnode *parent, int iip);
+struct ubifs_nnode *ubifs_get_nnode(struct ubifs_info *c,
+ struct ubifs_nnode *parent, int iip);
+int ubifs_read_nnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip);
+void ubifs_add_lpt_dirt(struct ubifs_info *c, int lnum, int dirty);
+void ubifs_add_nnode_dirt(struct ubifs_info *c, struct ubifs_nnode *nnode);
+uint32_t ubifs_unpack_bits(uint8_t **addr, int *pos, int nrbits);
+struct ubifs_nnode *ubifs_first_nnode(struct ubifs_info *c, int *hght);
+
+/* lpt_commit.c */
+int ubifs_lpt_start_commit(struct ubifs_info *c);
+int ubifs_lpt_end_commit(struct ubifs_info *c);
+int ubifs_lpt_post_commit(struct ubifs_info *c);
+void ubifs_lpt_free(struct ubifs_info *c, int wr_only);
+
+/* lprops.c */
+void ubifs_get_lprops(struct ubifs_info *c);
+const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c,
+ const struct ubifs_lprops *lp,
+ int free, int dirty, int flags,
+ int idx_gc_cnt);
+void ubifs_release_lprops(struct ubifs_info *c);
+void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *stats);
+void ubifs_add_to_cat(struct ubifs_info *c, struct ubifs_lprops *lprops,
+ int cat);
+void ubifs_replace_cat(struct ubifs_info *c, struct ubifs_lprops *old_lprops,
+ struct ubifs_lprops *new_lprops);
+void ubifs_ensure_cat(struct ubifs_info *c, struct ubifs_lprops *lprops);
+int ubifs_categorize_lprops(const struct ubifs_info *c,
+ const struct ubifs_lprops *lprops);
+int ubifs_change_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
+ int flags_set, int flags_clean, int idx_gc_cnt);
+int ubifs_update_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
+ int flags_set, int flags_clean);
+int ubifs_read_one_lp(struct ubifs_info *c, int lnum, struct ubifs_lprops *lp);
+const struct ubifs_lprops *ubifs_fast_find_free(struct ubifs_info *c);
+const struct ubifs_lprops *ubifs_fast_find_empty(struct ubifs_info *c);
+const struct ubifs_lprops *ubifs_fast_find_freeable(struct ubifs_info *c);
+const struct ubifs_lprops *ubifs_fast_find_frdi_idx(struct ubifs_info *c);
+
+/* file.c */
+int ubifs_fsync(struct file *file, struct dentry *dentry, int datasync);
+int ubifs_setattr(struct dentry *dentry, struct iattr *attr);
+
+/* dir.c */
+struct inode *ubifs_new_inode(struct ubifs_info *c, const struct inode *dir,
+ int mode);
+int ubifs_getattr(struct vfsmount *mnt, struct dentry *dentry,
+ struct kstat *stat);
+
+/* xattr.c */
+int ubifs_setxattr(struct dentry *dentry, const char *name,
+ const void *value, size_t size, int flags);
+ssize_t ubifs_getxattr(struct dentry *dentry, const char *name, void *buf,
+ size_t size);
+ssize_t ubifs_listxattr(struct dentry *dentry, char *buffer, size_t size);
+int ubifs_removexattr(struct dentry *dentry, const char *name);
+
+/* super.c */
+struct inode *ubifs_iget(struct super_block *sb, unsigned long inum);
+
+/* recovery.c */
+int ubifs_recover_master_node(struct ubifs_info *c);
+int ubifs_write_rcvrd_mst_node(struct ubifs_info *c);
+struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum,
+ int offs, void *sbuf, int grouped);
+struct ubifs_scan_leb *ubifs_recover_log_leb(struct ubifs_info *c, int lnum,
+ int offs, void *sbuf);
+int ubifs_recover_inl_heads(const struct ubifs_info *c, void *sbuf);
+int ubifs_clean_lebs(const struct ubifs_info *c, void *sbuf);
+int ubifs_rcvry_gc_commit(struct ubifs_info *c);
+int ubifs_recover_size_accum(struct ubifs_info *c, union ubifs_key *key,
+ int deletion, loff_t new_size);
+int ubifs_recover_size(struct ubifs_info *c);
+void ubifs_destroy_size_tree(struct ubifs_info *c);
+
+/* ioctl.c */
+long ubifs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+void ubifs_set_inode_flags(struct inode *inode);
+#ifdef CONFIG_COMPAT
+long ubifs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+#endif
+
+/* compressor.c */
+int __init ubifs_compressors_init(void);
+void __exit ubifs_compressors_exit(void);
+void ubifs_compress(const void *in_buf, int in_len, void *out_buf, int *out_len,
+ int *compr_type);
+int ubifs_decompress(const void *buf, int len, void *out, int *out_len,
+ int compr_type);
+
+#include "debug.h"
+#include "misc.h"
+#include "key.h"
+
+#endif /* !__UBIFS_H__ */
--- /dev/null
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ * Adrian Hunter
+ */
+
+/*
+ * This file implements UBIFS extended attributes support.
+ *
+ * Extended attributes are implemented as regular inodes with attached data,
+ * which limits extended attribute size to UBIFS block size (4KiB). Names of
+ * extended attributes are described by extended attribute entries (xentries),
+ * which are almost identical to directory entries, but have different key type.
+ *
+ * In other words, the situation with extended attributes is very similar to
+ * directories. Indeed, any inode (but of course not xattr inodes) may have a
+ * number of associated xentries, just like directory inodes have associated
+ * directory entries. Extended attribute entries store the name of the extended
+ * attribute, the host inode number, and the extended attribute inode number.
+ * Similarly, direntries store the name, the parent and the target inode
+ * numbers. Thus, most of the common UBIFS mechanisms may be re-used for
+ * extended attributes.
+ *
+ * The number of extended attributes is not limited, but there is Linux
+ * limitation on the maximum possible size of the list of all extended
+ * attributes associated with an inode (%XATTR_LIST_MAX), so UBIFS makes sure
+ * the sum of all extended attribute names of the inode does not exceed that
+ * limit.
+ *
+ * Extended attributes are synchronous, which means they are written to the
+ * flash media synchronously and there is no write-back for extended attribute
+ * inodes. The extended attribute values are not stored in compressed form on
+ * the media.
+ *
+ * Since extended attributes are represented by regular inodes, they are cached
+ * in the VFS inode cache. The xentries are cached in the LNC cache (see
+ * tnc.c).
+ *
+ * ACL support is not implemented.
+ */
+
+#include <linux/xattr.h>
+#include <linux/posix_acl_xattr.h>
+#include "ubifs.h"
+
+/*
+ * Limit the number of extended attributes per inode so that the total size
+ * (xattr_size) is guaranteeded to fit in an 'unsigned int'.
+ */
+#define MAX_XATTRS_PER_INODE 65535
+
+/*
+ * Extended attribute type constants.
+ *
+ * USER_XATTR: user extended attribute ("user.*")
+ * TRUSTED_XATTR: trusted extended attribute ("trusted.*)
+ * SECURITY_XATTR: security extended attribute ("security.*")
+ */
+enum {
+ USER_XATTR,
+ TRUSTED_XATTR,
+ SECURITY_XATTR,
+};
+
+static struct inode_operations none_inode_operations;
+static struct address_space_operations none_address_operations;
+static struct file_operations none_file_operations;
+
+/**
+ * create_xattr - create an extended attribute.
+ * @c: UBIFS file-system description object
+ * @host: host inode
+ * @nm: extended attribute name
+ * @value: extended attribute value
+ * @size: size of extended attribute value
+ *
+ * This is a helper function which creates an extended attribute of name @nm
+ * and value @value for inode @host. The host inode is also updated on flash
+ * because the ctime and extended attribute accounting data changes. This
+ * function returns zero in case of success and a negative error code in case
+ * of failure.
+ */
+static int create_xattr(struct ubifs_info *c, struct inode *host,
+ const struct qstr *nm, const void *value, int size)
+{
+ int err;
+ struct inode *inode;
+ struct ubifs_inode *ui, *host_ui = ubifs_inode(host);
+ struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
+ .new_ino_d = size, .dirtied_ino = 1,
+ .dirtied_ino_d = host_ui->data_len};
+
+ if (host_ui->xattr_cnt >= MAX_XATTRS_PER_INODE)
+ return -ENOSPC;
+ /*
+ * Linux limits the maximum size of the extended attribute names list
+ * to %XATTR_LIST_MAX. This means we should not allow creating more*
+ * extended attributes if the name list becomes larger. This limitation
+ * is artificial for UBIFS, though.
+ */
+ if (host_ui->xattr_names + host_ui->xattr_cnt +
+ nm->len + 1 > XATTR_LIST_MAX)
+ return -ENOSPC;
+
+ err = ubifs_budget_space(c, &req);
+ if (err)
+ return err;
+
+ inode = ubifs_new_inode(c, host, S_IFREG | S_IRWXUGO);
+ if (IS_ERR(inode)) {
+ err = PTR_ERR(inode);
+ goto out_budg;
+ }
+
+ mutex_lock(&host_ui->ui_mutex);
+ /* Re-define all operations to be "nothing" */
+ inode->i_mapping->a_ops = &none_address_operations;
+ inode->i_op = &none_inode_operations;
+ inode->i_fop = &none_file_operations;
+
+ inode->i_flags |= S_SYNC | S_NOATIME | S_NOCMTIME | S_NOQUOTA;
+ ui = ubifs_inode(inode);
+ ui->xattr = 1;
+ ui->flags |= UBIFS_XATTR_FL;
+ ui->data = kmalloc(size, GFP_NOFS);
+ if (!ui->data) {
+ err = -ENOMEM;
+ goto out_unlock;
+ }
+
+ memcpy(ui->data, value, size);
+ host->i_ctime = ubifs_current_time(host);
+ host_ui->xattr_cnt += 1;
+ host_ui->xattr_size += CALC_DENT_SIZE(nm->len);
+ host_ui->xattr_size += CALC_XATTR_BYTES(size);
+ host_ui->xattr_names += nm->len;
+
+ /*
+ * We do not use i_size_write() because nobody can race with us as we
+ * are holding host @host->i_mutex - every xattr operation for this
+ * inode is serialized by it.
+ */
+ inode->i_size = ui->ui_size = size;
+ ui->data_len = size;
+ err = ubifs_jnl_update(c, host, nm, inode, 0, 1);
+ if (err)
+ goto out_cancel;
+ mutex_unlock(&host_ui->ui_mutex);
+
+ ubifs_release_budget(c, &req);
+ insert_inode_hash(inode);
+ iput(inode);
+ return 0;
+
+out_cancel:
+ host_ui->xattr_cnt -= 1;
+ host_ui->xattr_size -= CALC_DENT_SIZE(nm->len);
+ host_ui->xattr_size -= CALC_XATTR_BYTES(size);
+out_unlock:
+ mutex_unlock(&host_ui->ui_mutex);
+ make_bad_inode(inode);
+ iput(inode);
+out_budg:
+ ubifs_release_budget(c, &req);
+ return err;
+}
+
+/**
+ * change_xattr - change an extended attribute.
+ * @c: UBIFS file-system description object
+ * @host: host inode
+ * @inode: extended attribute inode
+ * @value: extended attribute value
+ * @size: size of extended attribute value
+ *
+ * This helper function changes the value of extended attribute @inode with new
+ * data from @value. Returns zero in case of success and a negative error code
+ * in case of failure.
+ */
+static int change_xattr(struct ubifs_info *c, struct inode *host,
+ struct inode *inode, const void *value, int size)
+{
+ int err;
+ struct ubifs_inode *host_ui = ubifs_inode(host);
+ struct ubifs_inode *ui = ubifs_inode(inode);
+ struct ubifs_budget_req req = { .dirtied_ino = 2,
+ .dirtied_ino_d = size + host_ui->data_len };
+
+ ubifs_assert(ui->data_len == inode->i_size);
+ err = ubifs_budget_space(c, &req);
+ if (err)
+ return err;
+
+ mutex_lock(&host_ui->ui_mutex);
+ host->i_ctime = ubifs_current_time(host);
+ host_ui->xattr_size -= CALC_XATTR_BYTES(ui->data_len);
+ host_ui->xattr_size += CALC_XATTR_BYTES(size);
+
+ kfree(ui->data);
+ ui->data = kmalloc(size, GFP_NOFS);
+ if (!ui->data) {
+ err = -ENOMEM;
+ goto out_unlock;
+ }
+
+ memcpy(ui->data, value, size);
+ inode->i_size = ui->ui_size = size;
+ ui->data_len = size;
+
+ /*
+ * It is important to write the host inode after the xattr inode
+ * because if the host inode gets synchronized (via 'fsync()'), then
+ * the extended attribute inode gets synchronized, because it goes
+ * before the host inode in the write-buffer.
+ */
+ err = ubifs_jnl_change_xattr(c, inode, host);
+ if (err)
+ goto out_cancel;
+ mutex_unlock(&host_ui->ui_mutex);
+
+ ubifs_release_budget(c, &req);
+ return 0;
+
+out_cancel:
+ host_ui->xattr_size -= CALC_XATTR_BYTES(size);
+ host_ui->xattr_size += CALC_XATTR_BYTES(ui->data_len);
+ make_bad_inode(inode);
+out_unlock:
+ mutex_unlock(&host_ui->ui_mutex);
+ ubifs_release_budget(c, &req);
+ return err;
+}
+
+/**
+ * check_namespace - check extended attribute name-space.
+ * @nm: extended attribute name
+ *
+ * This function makes sure the extended attribute name belongs to one of the
+ * supported extended attribute name-spaces. Returns name-space index in case
+ * of success and a negative error code in case of failure.
+ */
+static int check_namespace(const struct qstr *nm)
+{
+ int type;
+
+ if (nm->len > UBIFS_MAX_NLEN)
+ return -ENAMETOOLONG;
+
+ if (!strncmp(nm->name, XATTR_TRUSTED_PREFIX,
+ XATTR_TRUSTED_PREFIX_LEN)) {
+ if (nm->name[sizeof(XATTR_TRUSTED_PREFIX) - 1] == '\0')
+ return -EINVAL;
+ type = TRUSTED_XATTR;
+ } else if (!strncmp(nm->name, XATTR_USER_PREFIX,
+ XATTR_USER_PREFIX_LEN)) {
+ if (nm->name[XATTR_USER_PREFIX_LEN] == '\0')
+ return -EINVAL;
+ type = USER_XATTR;
+ } else if (!strncmp(nm->name, XATTR_SECURITY_PREFIX,
+ XATTR_SECURITY_PREFIX_LEN)) {
+ if (nm->name[sizeof(XATTR_SECURITY_PREFIX) - 1] == '\0')
+ return -EINVAL;
+ type = SECURITY_XATTR;
+ } else
+ return -EOPNOTSUPP;
+
+ return type;
+}
+
+static struct inode *iget_xattr(struct ubifs_info *c, ino_t inum)
+{
+ struct inode *inode;
+
+ inode = ubifs_iget(c->vfs_sb, inum);
+ if (IS_ERR(inode)) {
+ ubifs_err("dead extended attribute entry, error %d",
+ (int)PTR_ERR(inode));
+ return inode;
+ }
+ if (ubifs_inode(inode)->xattr)
+ return inode;
+ ubifs_err("corrupt extended attribute entry");
+ iput(inode);
+ return ERR_PTR(-EINVAL);
+}
+
+int ubifs_setxattr(struct dentry *dentry, const char *name,
+ const void *value, size_t size, int flags)
+{
+ struct inode *inode, *host = dentry->d_inode;
+ struct ubifs_info *c = host->i_sb->s_fs_info;
+ struct qstr nm = { .name = name, .len = strlen(name) };
+ struct ubifs_dent_node *xent;
+ union ubifs_key key;
+ int err, type;
+
+ dbg_gen("xattr '%s', host ino %lu ('%.*s'), size %zd", name,
+ host->i_ino, dentry->d_name.len, dentry->d_name.name, size);
+
+ if (size > UBIFS_MAX_INO_DATA)
+ return -ERANGE;
+
+ type = check_namespace(&nm);
+ if (type < 0)
+ return type;
+
+ xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS);
+ if (!xent)
+ return -ENOMEM;
+
+ /*
+ * The extended attribute entries are stored in LNC, so multiple
+ * look-ups do not involve reading the flash.
+ */
+ xent_key_init(c, &key, host->i_ino, &nm);
+ err = ubifs_tnc_lookup_nm(c, &key, xent, &nm);
+ if (err) {
+ if (err != -ENOENT)
+ goto out_free;
+
+ if (flags & XATTR_REPLACE)
+ /* We are asked not to create the xattr */
+ err = -ENODATA;
+ else
+ err = create_xattr(c, host, &nm, value, size);
+ goto out_free;
+ }
+
+ if (flags & XATTR_CREATE) {
+ /* We are asked not to replace the xattr */
+ err = -EEXIST;
+ goto out_free;
+ }
+
+ inode = iget_xattr(c, le64_to_cpu(xent->inum));
+ if (IS_ERR(inode)) {
+ err = PTR_ERR(inode);
+ goto out_free;
+ }
+
+ err = change_xattr(c, host, inode, value, size);
+ iput(inode);
+
+out_free:
+ kfree(xent);
+ return err;
+}
+
+ssize_t ubifs_getxattr(struct dentry *dentry, const char *name, void *buf,
+ size_t size)
+{
+ struct inode *inode, *host = dentry->d_inode;
+ struct ubifs_info *c = host->i_sb->s_fs_info;
+ struct qstr nm = { .name = name, .len = strlen(name) };
+ struct ubifs_inode *ui;
+ struct ubifs_dent_node *xent;
+ union ubifs_key key;
+ int err;
+
+ dbg_gen("xattr '%s', ino %lu ('%.*s'), buf size %zd", name,
+ host->i_ino, dentry->d_name.len, dentry->d_name.name, size);
+
+ err = check_namespace(&nm);
+ if (err < 0)
+ return err;
+
+ xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS);
+ if (!xent)
+ return -ENOMEM;
+
+ mutex_lock(&host->i_mutex);
+ xent_key_init(c, &key, host->i_ino, &nm);
+ err = ubifs_tnc_lookup_nm(c, &key, xent, &nm);
+ if (err) {
+ if (err == -ENOENT)
+ err = -ENODATA;
+ goto out_unlock;
+ }
+
+ inode = iget_xattr(c, le64_to_cpu(xent->inum));
+ if (IS_ERR(inode)) {
+ err = PTR_ERR(inode);
+ goto out_unlock;
+ }
+
+ ui = ubifs_inode(inode);
+ ubifs_assert(inode->i_size == ui->data_len);
+ ubifs_assert(ubifs_inode(host)->xattr_size > ui->data_len);
+
+ if (buf) {
+ /* If @buf is %NULL we are supposed to return the length */
+ if (ui->data_len > size) {
+ dbg_err("buffer size %zd, xattr len %d",
+ size, ui->data_len);
+ err = -ERANGE;
+ goto out_iput;
+ }
+
+ memcpy(buf, ui->data, ui->data_len);
+ }
+ err = ui->data_len;
+
+out_iput:
+ iput(inode);
+out_unlock:
+ mutex_unlock(&host->i_mutex);
+ kfree(xent);
+ return err;
+}
+
+ssize_t ubifs_listxattr(struct dentry *dentry, char *buffer, size_t size)
+{
+ union ubifs_key key;
+ struct inode *host = dentry->d_inode;
+ struct ubifs_info *c = host->i_sb->s_fs_info;
+ struct ubifs_inode *host_ui = ubifs_inode(host);
+ struct ubifs_dent_node *xent, *pxent = NULL;
+ int err, len, written = 0;
+ struct qstr nm = { .name = NULL };
+
+ dbg_gen("ino %lu ('%.*s'), buffer size %zd", host->i_ino,
+ dentry->d_name.len, dentry->d_name.name, size);
+
+ len = host_ui->xattr_names + host_ui->xattr_cnt;
+ if (!buffer)
+ /*
+ * We should return the minimum buffer size which will fit a
+ * null-terminated list of all the extended attribute names.
+ */
+ return len;
+
+ if (len > size)
+ return -ERANGE;
+
+ lowest_xent_key(c, &key, host->i_ino);
+
+ mutex_lock(&host->i_mutex);
+ while (1) {
+ int type;
+
+ xent = ubifs_tnc_next_ent(c, &key, &nm);
+ if (unlikely(IS_ERR(xent))) {
+ err = PTR_ERR(xent);
+ break;
+ }
+
+ nm.name = xent->name;
+ nm.len = le16_to_cpu(xent->nlen);
+
+ type = check_namespace(&nm);
+ if (unlikely(type < 0)) {
+ err = type;
+ break;
+ }
+
+ /* Show trusted namespace only for "power" users */
+ if (type != TRUSTED_XATTR || capable(CAP_SYS_ADMIN)) {
+ memcpy(buffer + written, nm.name, nm.len + 1);
+ written += nm.len + 1;
+ }
+
+ kfree(pxent);
+ pxent = xent;
+ key_read(c, &xent->key, &key);
+ }
+ mutex_unlock(&host->i_mutex);
+
+ kfree(pxent);
+ if (err != -ENOENT) {
+ ubifs_err("cannot find next direntry, error %d", err);
+ return err;
+ }
+
+ ubifs_assert(written <= size);
+ return written;
+}
+
+static int remove_xattr(struct ubifs_info *c, struct inode *host,
+ struct inode *inode, const struct qstr *nm)
+{
+ int err;
+ struct ubifs_inode *host_ui = ubifs_inode(host);
+ struct ubifs_inode *ui = ubifs_inode(inode);
+ struct ubifs_budget_req req = { .dirtied_ino = 1, .mod_dent = 1,
+ .dirtied_ino_d = host_ui->data_len };
+
+ ubifs_assert(ui->data_len == inode->i_size);
+
+ err = ubifs_budget_space(c, &req);
+ if (err)
+ return err;
+
+ mutex_lock(&host_ui->ui_mutex);
+ host->i_ctime = ubifs_current_time(host);
+ host_ui->xattr_cnt -= 1;
+ host_ui->xattr_size -= CALC_DENT_SIZE(nm->len);
+ host_ui->xattr_size -= CALC_XATTR_BYTES(ui->data_len);
+ host_ui->xattr_names -= nm->len;
+
+ err = ubifs_jnl_delete_xattr(c, host, inode, nm);
+ if (err)
+ goto out_cancel;
+ mutex_unlock(&host_ui->ui_mutex);
+
+ ubifs_release_budget(c, &req);
+ return 0;
+
+out_cancel:
+ host_ui->xattr_cnt += 1;
+ host_ui->xattr_size += CALC_DENT_SIZE(nm->len);
+ host_ui->xattr_size += CALC_XATTR_BYTES(ui->data_len);
+ mutex_unlock(&host_ui->ui_mutex);
+ ubifs_release_budget(c, &req);
+ make_bad_inode(inode);
+ return err;
+}
+
+int ubifs_removexattr(struct dentry *dentry, const char *name)
+{
+ struct inode *inode, *host = dentry->d_inode;
+ struct ubifs_info *c = host->i_sb->s_fs_info;
+ struct qstr nm = { .name = name, .len = strlen(name) };
+ struct ubifs_dent_node *xent;
+ union ubifs_key key;
+ int err;
+
+ dbg_gen("xattr '%s', ino %lu ('%.*s')", name,
+ host->i_ino, dentry->d_name.len, dentry->d_name.name);
+ ubifs_assert(mutex_is_locked(&host->i_mutex));
+
+ err = check_namespace(&nm);
+ if (err < 0)
+ return err;
+
+ xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS);
+ if (!xent)
+ return -ENOMEM;
+
+ xent_key_init(c, &key, host->i_ino, &nm);
+ err = ubifs_tnc_lookup_nm(c, &key, xent, &nm);
+ if (err) {
+ if (err == -ENOENT)
+ err = -ENODATA;
+ goto out_free;
+ }
+
+ inode = iget_xattr(c, le64_to_cpu(xent->inum));
+ if (IS_ERR(inode)) {
+ err = PTR_ERR(inode);
+ goto out_free;
+ }
+
+ ubifs_assert(inode->i_nlink == 1);
+ inode->i_nlink = 0;
+ err = remove_xattr(c, host, inode, &nm);
+ if (err)
+ inode->i_nlink = 1;
+
+ /* If @i_nlink is 0, 'iput()' will delete the inode */
+ iput(inode);
+
+out_free:
+ kfree(xent);
+ return err;
+}
extern int invalidate_inode_pages2(struct address_space *mapping);
extern int invalidate_inode_pages2_range(struct address_space *mapping,
pgoff_t start, pgoff_t end);
+extern void generic_sync_sb_inodes(struct super_block *sb,
+ struct writeback_control *wbc);
extern int write_inode_now(struct inode *, int);
extern int filemap_fdatawrite(struct address_space *);
extern int filemap_flush(struct address_space *);
if (saved_root_name[0]) {
root_device_name = saved_root_name;
- if (!strncmp(root_device_name, "mtd", 3)) {
+ if (!strncmp(root_device_name, "mtd", 3) ||
+ !strncmp(root_device_name, "ubi", 3)) {
mount_block_root(root_device_name, root_mountflags);
goto out;
}
git.openpandora.org / pandora-kernel.git / commitdiff