2 * Copyright (c) 2003-2006, Cluster File Systems, Inc, info@clusterfs.com
3 * Written by Alex Tomas <alex@clusterfs.com>
5 * Architecture independence:
6 * Copyright (c) 2005, Bull S.A.
7 * Written by Pierre Peiffer <pierre.peiffer@bull.net>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public Licens
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
24 * Extents support for EXT4
27 * - ext4*_error() should be used in some situations
28 * - analyze all BUG()/BUG_ON(), use -EIO where appropriate
29 * - smart tree reduction
32 #include <linux/module.h>
34 #include <linux/time.h>
35 #include <linux/jbd2.h>
36 #include <linux/highuid.h>
37 #include <linux/pagemap.h>
38 #include <linux/quotaops.h>
39 #include <linux/string.h>
40 #include <linux/slab.h>
41 #include <linux/falloc.h>
42 #include <asm/uaccess.h>
43 #include <linux/fiemap.h>
44 #include "ext4_jbd2.h"
45 #include "ext4_extents.h"
47 #include <trace/events/ext4.h>
49 static int ext4_split_extent(handle_t *handle,
51 struct ext4_ext_path *path,
52 struct ext4_map_blocks *map,
56 static int ext4_ext_truncate_extend_restart(handle_t *handle,
62 if (!ext4_handle_valid(handle))
64 if (handle->h_buffer_credits > needed)
66 err = ext4_journal_extend(handle, needed);
69 err = ext4_truncate_restart_trans(handle, inode, needed);
81 static int ext4_ext_get_access(handle_t *handle, struct inode *inode,
82 struct ext4_ext_path *path)
85 /* path points to block */
86 return ext4_journal_get_write_access(handle, path->p_bh);
88 /* path points to leaf/index in inode body */
89 /* we use in-core data, no need to protect them */
99 static int ext4_ext_dirty(handle_t *handle, struct inode *inode,
100 struct ext4_ext_path *path)
104 /* path points to block */
105 err = ext4_handle_dirty_metadata(handle, inode, path->p_bh);
107 /* path points to leaf/index in inode body */
108 err = ext4_mark_inode_dirty(handle, inode);
113 static ext4_fsblk_t ext4_ext_find_goal(struct inode *inode,
114 struct ext4_ext_path *path,
117 struct ext4_inode_info *ei = EXT4_I(inode);
118 ext4_fsblk_t bg_start;
119 ext4_fsblk_t last_block;
120 ext4_grpblk_t colour;
121 ext4_group_t block_group;
122 int flex_size = ext4_flex_bg_size(EXT4_SB(inode->i_sb));
126 struct ext4_extent *ex;
127 depth = path->p_depth;
130 * Try to predict block placement assuming that we are
131 * filling in a file which will eventually be
132 * non-sparse --- i.e., in the case of libbfd writing
133 * an ELF object sections out-of-order but in a way
134 * the eventually results in a contiguous object or
135 * executable file, or some database extending a table
136 * space file. However, this is actually somewhat
137 * non-ideal if we are writing a sparse file such as
138 * qemu or KVM writing a raw image file that is going
139 * to stay fairly sparse, since it will end up
140 * fragmenting the file system's free space. Maybe we
141 * should have some hueristics or some way to allow
142 * userspace to pass a hint to file system,
143 * especially if the latter case turns out to be
146 ex = path[depth].p_ext;
148 ext4_fsblk_t ext_pblk = ext4_ext_pblock(ex);
149 ext4_lblk_t ext_block = le32_to_cpu(ex->ee_block);
151 if (block > ext_block)
152 return ext_pblk + (block - ext_block);
154 return ext_pblk - (ext_block - block);
157 /* it looks like index is empty;
158 * try to find starting block from index itself */
159 if (path[depth].p_bh)
160 return path[depth].p_bh->b_blocknr;
163 /* OK. use inode's group */
164 block_group = ei->i_block_group;
165 if (flex_size >= EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME) {
167 * If there are at least EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME
168 * block groups per flexgroup, reserve the first block
169 * group for directories and special files. Regular
170 * files will start at the second block group. This
171 * tends to speed up directory access and improves
174 block_group &= ~(flex_size-1);
175 if (S_ISREG(inode->i_mode))
178 bg_start = ext4_group_first_block_no(inode->i_sb, block_group);
179 last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1;
182 * If we are doing delayed allocation, we don't need take
183 * colour into account.
185 if (test_opt(inode->i_sb, DELALLOC))
188 if (bg_start + EXT4_BLOCKS_PER_GROUP(inode->i_sb) <= last_block)
189 colour = (current->pid % 16) *
190 (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16);
192 colour = (current->pid % 16) * ((last_block - bg_start) / 16);
193 return bg_start + colour + block;
197 * Allocation for a meta data block
200 ext4_ext_new_meta_block(handle_t *handle, struct inode *inode,
201 struct ext4_ext_path *path,
202 struct ext4_extent *ex, int *err, unsigned int flags)
204 ext4_fsblk_t goal, newblock;
206 goal = ext4_ext_find_goal(inode, path, le32_to_cpu(ex->ee_block));
207 newblock = ext4_new_meta_blocks(handle, inode, goal, flags,
212 static inline int ext4_ext_space_block(struct inode *inode, int check)
216 size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
217 / sizeof(struct ext4_extent);
219 #ifdef AGGRESSIVE_TEST
227 static inline int ext4_ext_space_block_idx(struct inode *inode, int check)
231 size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
232 / sizeof(struct ext4_extent_idx);
234 #ifdef AGGRESSIVE_TEST
242 static inline int ext4_ext_space_root(struct inode *inode, int check)
246 size = sizeof(EXT4_I(inode)->i_data);
247 size -= sizeof(struct ext4_extent_header);
248 size /= sizeof(struct ext4_extent);
250 #ifdef AGGRESSIVE_TEST
258 static inline int ext4_ext_space_root_idx(struct inode *inode, int check)
262 size = sizeof(EXT4_I(inode)->i_data);
263 size -= sizeof(struct ext4_extent_header);
264 size /= sizeof(struct ext4_extent_idx);
266 #ifdef AGGRESSIVE_TEST
275 * Calculate the number of metadata blocks needed
276 * to allocate @blocks
277 * Worse case is one block per extent
279 int ext4_ext_calc_metadata_amount(struct inode *inode, ext4_lblk_t lblock)
281 struct ext4_inode_info *ei = EXT4_I(inode);
284 idxs = ((inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
285 / sizeof(struct ext4_extent_idx));
288 * If the new delayed allocation block is contiguous with the
289 * previous da block, it can share index blocks with the
290 * previous block, so we only need to allocate a new index
291 * block every idxs leaf blocks. At ldxs**2 blocks, we need
292 * an additional index block, and at ldxs**3 blocks, yet
293 * another index blocks.
295 if (ei->i_da_metadata_calc_len &&
296 ei->i_da_metadata_calc_last_lblock+1 == lblock) {
297 if ((ei->i_da_metadata_calc_len % idxs) == 0)
299 if ((ei->i_da_metadata_calc_len % (idxs*idxs)) == 0)
301 if ((ei->i_da_metadata_calc_len % (idxs*idxs*idxs)) == 0) {
303 ei->i_da_metadata_calc_len = 0;
305 ei->i_da_metadata_calc_len++;
306 ei->i_da_metadata_calc_last_lblock++;
311 * In the worst case we need a new set of index blocks at
312 * every level of the inode's extent tree.
314 ei->i_da_metadata_calc_len = 1;
315 ei->i_da_metadata_calc_last_lblock = lblock;
316 return ext_depth(inode) + 1;
320 ext4_ext_max_entries(struct inode *inode, int depth)
324 if (depth == ext_depth(inode)) {
326 max = ext4_ext_space_root(inode, 1);
328 max = ext4_ext_space_root_idx(inode, 1);
331 max = ext4_ext_space_block(inode, 1);
333 max = ext4_ext_space_block_idx(inode, 1);
339 static int ext4_valid_extent(struct inode *inode, struct ext4_extent *ext)
341 ext4_fsblk_t block = ext4_ext_pblock(ext);
342 int len = ext4_ext_get_actual_len(ext);
344 return ext4_data_block_valid(EXT4_SB(inode->i_sb), block, len);
347 static int ext4_valid_extent_idx(struct inode *inode,
348 struct ext4_extent_idx *ext_idx)
350 ext4_fsblk_t block = ext4_idx_pblock(ext_idx);
352 return ext4_data_block_valid(EXT4_SB(inode->i_sb), block, 1);
355 static int ext4_valid_extent_entries(struct inode *inode,
356 struct ext4_extent_header *eh,
359 struct ext4_extent *ext;
360 struct ext4_extent_idx *ext_idx;
361 unsigned short entries;
362 if (eh->eh_entries == 0)
365 entries = le16_to_cpu(eh->eh_entries);
369 ext = EXT_FIRST_EXTENT(eh);
371 if (!ext4_valid_extent(inode, ext))
377 ext_idx = EXT_FIRST_INDEX(eh);
379 if (!ext4_valid_extent_idx(inode, ext_idx))
388 static int __ext4_ext_check(const char *function, unsigned int line,
389 struct inode *inode, struct ext4_extent_header *eh,
392 const char *error_msg;
395 if (unlikely(eh->eh_magic != EXT4_EXT_MAGIC)) {
396 error_msg = "invalid magic";
399 if (unlikely(le16_to_cpu(eh->eh_depth) != depth)) {
400 error_msg = "unexpected eh_depth";
403 if (unlikely(eh->eh_max == 0)) {
404 error_msg = "invalid eh_max";
407 max = ext4_ext_max_entries(inode, depth);
408 if (unlikely(le16_to_cpu(eh->eh_max) > max)) {
409 error_msg = "too large eh_max";
412 if (unlikely(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max))) {
413 error_msg = "invalid eh_entries";
416 if (!ext4_valid_extent_entries(inode, eh, depth)) {
417 error_msg = "invalid extent entries";
423 ext4_error_inode(inode, function, line, 0,
424 "bad header/extent: %s - magic %x, "
425 "entries %u, max %u(%u), depth %u(%u)",
426 error_msg, le16_to_cpu(eh->eh_magic),
427 le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max),
428 max, le16_to_cpu(eh->eh_depth), depth);
433 #define ext4_ext_check(inode, eh, depth) \
434 __ext4_ext_check(__func__, __LINE__, inode, eh, depth)
436 int ext4_ext_check_inode(struct inode *inode)
438 return ext4_ext_check(inode, ext_inode_hdr(inode), ext_depth(inode));
442 static void ext4_ext_show_path(struct inode *inode, struct ext4_ext_path *path)
444 int k, l = path->p_depth;
447 for (k = 0; k <= l; k++, path++) {
449 ext_debug(" %d->%llu", le32_to_cpu(path->p_idx->ei_block),
450 ext4_idx_pblock(path->p_idx));
451 } else if (path->p_ext) {
452 ext_debug(" %d:[%d]%d:%llu ",
453 le32_to_cpu(path->p_ext->ee_block),
454 ext4_ext_is_uninitialized(path->p_ext),
455 ext4_ext_get_actual_len(path->p_ext),
456 ext4_ext_pblock(path->p_ext));
463 static void ext4_ext_show_leaf(struct inode *inode, struct ext4_ext_path *path)
465 int depth = ext_depth(inode);
466 struct ext4_extent_header *eh;
467 struct ext4_extent *ex;
473 eh = path[depth].p_hdr;
474 ex = EXT_FIRST_EXTENT(eh);
476 ext_debug("Displaying leaf extents for inode %lu\n", inode->i_ino);
478 for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ex++) {
479 ext_debug("%d:[%d]%d:%llu ", le32_to_cpu(ex->ee_block),
480 ext4_ext_is_uninitialized(ex),
481 ext4_ext_get_actual_len(ex), ext4_ext_pblock(ex));
486 #define ext4_ext_show_path(inode, path)
487 #define ext4_ext_show_leaf(inode, path)
490 void ext4_ext_drop_refs(struct ext4_ext_path *path)
492 int depth = path->p_depth;
495 for (i = 0; i <= depth; i++, path++)
503 * ext4_ext_binsearch_idx:
504 * binary search for the closest index of the given block
505 * the header must be checked before calling this
508 ext4_ext_binsearch_idx(struct inode *inode,
509 struct ext4_ext_path *path, ext4_lblk_t block)
511 struct ext4_extent_header *eh = path->p_hdr;
512 struct ext4_extent_idx *r, *l, *m;
515 ext_debug("binsearch for %u(idx): ", block);
517 l = EXT_FIRST_INDEX(eh) + 1;
518 r = EXT_LAST_INDEX(eh);
521 if (block < le32_to_cpu(m->ei_block))
525 ext_debug("%p(%u):%p(%u):%p(%u) ", l, le32_to_cpu(l->ei_block),
526 m, le32_to_cpu(m->ei_block),
527 r, le32_to_cpu(r->ei_block));
531 ext_debug(" -> %d->%lld ", le32_to_cpu(path->p_idx->ei_block),
532 ext4_idx_pblock(path->p_idx));
534 #ifdef CHECK_BINSEARCH
536 struct ext4_extent_idx *chix, *ix;
539 chix = ix = EXT_FIRST_INDEX(eh);
540 for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ix++) {
542 le32_to_cpu(ix->ei_block) <= le32_to_cpu(ix[-1].ei_block)) {
543 printk(KERN_DEBUG "k=%d, ix=0x%p, "
545 ix, EXT_FIRST_INDEX(eh));
546 printk(KERN_DEBUG "%u <= %u\n",
547 le32_to_cpu(ix->ei_block),
548 le32_to_cpu(ix[-1].ei_block));
550 BUG_ON(k && le32_to_cpu(ix->ei_block)
551 <= le32_to_cpu(ix[-1].ei_block));
552 if (block < le32_to_cpu(ix->ei_block))
556 BUG_ON(chix != path->p_idx);
563 * ext4_ext_binsearch:
564 * binary search for closest extent of the given block
565 * the header must be checked before calling this
568 ext4_ext_binsearch(struct inode *inode,
569 struct ext4_ext_path *path, ext4_lblk_t block)
571 struct ext4_extent_header *eh = path->p_hdr;
572 struct ext4_extent *r, *l, *m;
574 if (eh->eh_entries == 0) {
576 * this leaf is empty:
577 * we get such a leaf in split/add case
582 ext_debug("binsearch for %u: ", block);
584 l = EXT_FIRST_EXTENT(eh) + 1;
585 r = EXT_LAST_EXTENT(eh);
589 if (block < le32_to_cpu(m->ee_block))
593 ext_debug("%p(%u):%p(%u):%p(%u) ", l, le32_to_cpu(l->ee_block),
594 m, le32_to_cpu(m->ee_block),
595 r, le32_to_cpu(r->ee_block));
599 ext_debug(" -> %d:%llu:[%d]%d ",
600 le32_to_cpu(path->p_ext->ee_block),
601 ext4_ext_pblock(path->p_ext),
602 ext4_ext_is_uninitialized(path->p_ext),
603 ext4_ext_get_actual_len(path->p_ext));
605 #ifdef CHECK_BINSEARCH
607 struct ext4_extent *chex, *ex;
610 chex = ex = EXT_FIRST_EXTENT(eh);
611 for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ex++) {
612 BUG_ON(k && le32_to_cpu(ex->ee_block)
613 <= le32_to_cpu(ex[-1].ee_block));
614 if (block < le32_to_cpu(ex->ee_block))
618 BUG_ON(chex != path->p_ext);
624 int ext4_ext_tree_init(handle_t *handle, struct inode *inode)
626 struct ext4_extent_header *eh;
628 eh = ext_inode_hdr(inode);
631 eh->eh_magic = EXT4_EXT_MAGIC;
632 eh->eh_max = cpu_to_le16(ext4_ext_space_root(inode, 0));
633 ext4_mark_inode_dirty(handle, inode);
634 ext4_ext_invalidate_cache(inode);
638 struct ext4_ext_path *
639 ext4_ext_find_extent(struct inode *inode, ext4_lblk_t block,
640 struct ext4_ext_path *path)
642 struct ext4_extent_header *eh;
643 struct buffer_head *bh;
644 short int depth, i, ppos = 0, alloc = 0;
646 eh = ext_inode_hdr(inode);
647 depth = ext_depth(inode);
649 /* account possible depth increase */
651 path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 2),
654 return ERR_PTR(-ENOMEM);
661 /* walk through the tree */
663 int need_to_validate = 0;
665 ext_debug("depth %d: num %d, max %d\n",
666 ppos, le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max));
668 ext4_ext_binsearch_idx(inode, path + ppos, block);
669 path[ppos].p_block = ext4_idx_pblock(path[ppos].p_idx);
670 path[ppos].p_depth = i;
671 path[ppos].p_ext = NULL;
673 bh = sb_getblk(inode->i_sb, path[ppos].p_block);
676 if (!bh_uptodate_or_lock(bh)) {
677 trace_ext4_ext_load_extent(inode, block,
679 if (bh_submit_read(bh) < 0) {
683 /* validate the extent entries */
684 need_to_validate = 1;
686 eh = ext_block_hdr(bh);
688 if (unlikely(ppos > depth)) {
690 EXT4_ERROR_INODE(inode,
691 "ppos %d > depth %d", ppos, depth);
694 path[ppos].p_bh = bh;
695 path[ppos].p_hdr = eh;
698 if (need_to_validate && ext4_ext_check(inode, eh, i))
702 path[ppos].p_depth = i;
703 path[ppos].p_ext = NULL;
704 path[ppos].p_idx = NULL;
707 ext4_ext_binsearch(inode, path + ppos, block);
708 /* if not an empty leaf */
709 if (path[ppos].p_ext)
710 path[ppos].p_block = ext4_ext_pblock(path[ppos].p_ext);
712 ext4_ext_show_path(inode, path);
717 ext4_ext_drop_refs(path);
720 return ERR_PTR(-EIO);
724 * ext4_ext_insert_index:
725 * insert new index [@logical;@ptr] into the block at @curp;
726 * check where to insert: before @curp or after @curp
728 static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
729 struct ext4_ext_path *curp,
730 int logical, ext4_fsblk_t ptr)
732 struct ext4_extent_idx *ix;
735 err = ext4_ext_get_access(handle, inode, curp);
739 if (unlikely(logical == le32_to_cpu(curp->p_idx->ei_block))) {
740 EXT4_ERROR_INODE(inode,
741 "logical %d == ei_block %d!",
742 logical, le32_to_cpu(curp->p_idx->ei_block));
745 len = EXT_MAX_INDEX(curp->p_hdr) - curp->p_idx;
746 if (logical > le32_to_cpu(curp->p_idx->ei_block)) {
748 if (curp->p_idx != EXT_LAST_INDEX(curp->p_hdr)) {
749 len = (len - 1) * sizeof(struct ext4_extent_idx);
750 len = len < 0 ? 0 : len;
751 ext_debug("insert new index %d after: %llu. "
752 "move %d from 0x%p to 0x%p\n",
754 (curp->p_idx + 1), (curp->p_idx + 2));
755 memmove(curp->p_idx + 2, curp->p_idx + 1, len);
757 ix = curp->p_idx + 1;
760 len = len * sizeof(struct ext4_extent_idx);
761 len = len < 0 ? 0 : len;
762 ext_debug("insert new index %d before: %llu. "
763 "move %d from 0x%p to 0x%p\n",
765 curp->p_idx, (curp->p_idx + 1));
766 memmove(curp->p_idx + 1, curp->p_idx, len);
770 ix->ei_block = cpu_to_le32(logical);
771 ext4_idx_store_pblock(ix, ptr);
772 le16_add_cpu(&curp->p_hdr->eh_entries, 1);
774 if (unlikely(le16_to_cpu(curp->p_hdr->eh_entries)
775 > le16_to_cpu(curp->p_hdr->eh_max))) {
776 EXT4_ERROR_INODE(inode,
777 "logical %d == ei_block %d!",
778 logical, le32_to_cpu(curp->p_idx->ei_block));
781 if (unlikely(ix > EXT_LAST_INDEX(curp->p_hdr))) {
782 EXT4_ERROR_INODE(inode, "ix > EXT_LAST_INDEX!");
786 err = ext4_ext_dirty(handle, inode, curp);
787 ext4_std_error(inode->i_sb, err);
794 * inserts new subtree into the path, using free index entry
796 * - allocates all needed blocks (new leaf and all intermediate index blocks)
797 * - makes decision where to split
798 * - moves remaining extents and index entries (right to the split point)
799 * into the newly allocated blocks
800 * - initializes subtree
802 static int ext4_ext_split(handle_t *handle, struct inode *inode,
804 struct ext4_ext_path *path,
805 struct ext4_extent *newext, int at)
807 struct buffer_head *bh = NULL;
808 int depth = ext_depth(inode);
809 struct ext4_extent_header *neh;
810 struct ext4_extent_idx *fidx;
811 struct ext4_extent *ex;
813 ext4_fsblk_t newblock, oldblock;
815 ext4_fsblk_t *ablocks = NULL; /* array of allocated blocks */
818 /* make decision: where to split? */
819 /* FIXME: now decision is simplest: at current extent */
821 /* if current leaf will be split, then we should use
822 * border from split point */
823 if (unlikely(path[depth].p_ext > EXT_MAX_EXTENT(path[depth].p_hdr))) {
824 EXT4_ERROR_INODE(inode, "p_ext > EXT_MAX_EXTENT!");
827 if (path[depth].p_ext != EXT_MAX_EXTENT(path[depth].p_hdr)) {
828 border = path[depth].p_ext[1].ee_block;
829 ext_debug("leaf will be split."
830 " next leaf starts at %d\n",
831 le32_to_cpu(border));
833 border = newext->ee_block;
834 ext_debug("leaf will be added."
835 " next leaf starts at %d\n",
836 le32_to_cpu(border));
840 * If error occurs, then we break processing
841 * and mark filesystem read-only. index won't
842 * be inserted and tree will be in consistent
843 * state. Next mount will repair buffers too.
847 * Get array to track all allocated blocks.
848 * We need this to handle errors and free blocks
851 ablocks = kzalloc(sizeof(ext4_fsblk_t) * depth, GFP_NOFS);
855 /* allocate all needed blocks */
856 ext_debug("allocate %d blocks for indexes/leaf\n", depth - at);
857 for (a = 0; a < depth - at; a++) {
858 newblock = ext4_ext_new_meta_block(handle, inode, path,
859 newext, &err, flags);
862 ablocks[a] = newblock;
865 /* initialize new leaf */
866 newblock = ablocks[--a];
867 if (unlikely(newblock == 0)) {
868 EXT4_ERROR_INODE(inode, "newblock == 0!");
872 bh = sb_getblk(inode->i_sb, newblock);
879 err = ext4_journal_get_create_access(handle, bh);
883 neh = ext_block_hdr(bh);
885 neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode, 0));
886 neh->eh_magic = EXT4_EXT_MAGIC;
888 ex = EXT_FIRST_EXTENT(neh);
890 /* move remainder of path[depth] to the new leaf */
891 if (unlikely(path[depth].p_hdr->eh_entries !=
892 path[depth].p_hdr->eh_max)) {
893 EXT4_ERROR_INODE(inode, "eh_entries %d != eh_max %d!",
894 path[depth].p_hdr->eh_entries,
895 path[depth].p_hdr->eh_max);
899 /* start copy from next extent */
900 /* TODO: we could do it by single memmove */
903 while (path[depth].p_ext <=
904 EXT_MAX_EXTENT(path[depth].p_hdr)) {
905 ext_debug("move %d:%llu:[%d]%d in new leaf %llu\n",
906 le32_to_cpu(path[depth].p_ext->ee_block),
907 ext4_ext_pblock(path[depth].p_ext),
908 ext4_ext_is_uninitialized(path[depth].p_ext),
909 ext4_ext_get_actual_len(path[depth].p_ext),
911 /*memmove(ex++, path[depth].p_ext++,
912 sizeof(struct ext4_extent));
918 memmove(ex, path[depth].p_ext-m, sizeof(struct ext4_extent)*m);
919 le16_add_cpu(&neh->eh_entries, m);
922 set_buffer_uptodate(bh);
925 err = ext4_handle_dirty_metadata(handle, inode, bh);
931 /* correct old leaf */
933 err = ext4_ext_get_access(handle, inode, path + depth);
936 le16_add_cpu(&path[depth].p_hdr->eh_entries, -m);
937 err = ext4_ext_dirty(handle, inode, path + depth);
943 /* create intermediate indexes */
945 if (unlikely(k < 0)) {
946 EXT4_ERROR_INODE(inode, "k %d < 0!", k);
951 ext_debug("create %d intermediate indices\n", k);
952 /* insert new index into current index block */
953 /* current depth stored in i var */
957 newblock = ablocks[--a];
958 bh = sb_getblk(inode->i_sb, newblock);
965 err = ext4_journal_get_create_access(handle, bh);
969 neh = ext_block_hdr(bh);
970 neh->eh_entries = cpu_to_le16(1);
971 neh->eh_magic = EXT4_EXT_MAGIC;
972 neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode, 0));
973 neh->eh_depth = cpu_to_le16(depth - i);
974 fidx = EXT_FIRST_INDEX(neh);
975 fidx->ei_block = border;
976 ext4_idx_store_pblock(fidx, oldblock);
978 ext_debug("int.index at %d (block %llu): %u -> %llu\n",
979 i, newblock, le32_to_cpu(border), oldblock);
984 ext_debug("cur 0x%p, last 0x%p\n", path[i].p_idx,
985 EXT_MAX_INDEX(path[i].p_hdr));
986 if (unlikely(EXT_MAX_INDEX(path[i].p_hdr) !=
987 EXT_LAST_INDEX(path[i].p_hdr))) {
988 EXT4_ERROR_INODE(inode,
989 "EXT_MAX_INDEX != EXT_LAST_INDEX ee_block %d!",
990 le32_to_cpu(path[i].p_ext->ee_block));
994 while (path[i].p_idx <= EXT_MAX_INDEX(path[i].p_hdr)) {
995 ext_debug("%d: move %d:%llu in new index %llu\n", i,
996 le32_to_cpu(path[i].p_idx->ei_block),
997 ext4_idx_pblock(path[i].p_idx),
999 /*memmove(++fidx, path[i].p_idx++,
1000 sizeof(struct ext4_extent_idx));
1002 BUG_ON(neh->eh_entries > neh->eh_max);*/
1007 memmove(++fidx, path[i].p_idx - m,
1008 sizeof(struct ext4_extent_idx) * m);
1009 le16_add_cpu(&neh->eh_entries, m);
1011 set_buffer_uptodate(bh);
1014 err = ext4_handle_dirty_metadata(handle, inode, bh);
1020 /* correct old index */
1022 err = ext4_ext_get_access(handle, inode, path + i);
1025 le16_add_cpu(&path[i].p_hdr->eh_entries, -m);
1026 err = ext4_ext_dirty(handle, inode, path + i);
1034 /* insert new index */
1035 err = ext4_ext_insert_index(handle, inode, path + at,
1036 le32_to_cpu(border), newblock);
1040 if (buffer_locked(bh))
1046 /* free all allocated blocks in error case */
1047 for (i = 0; i < depth; i++) {
1050 ext4_free_blocks(handle, inode, NULL, ablocks[i], 1,
1051 EXT4_FREE_BLOCKS_METADATA);
1060 * ext4_ext_grow_indepth:
1061 * implements tree growing procedure:
1062 * - allocates new block
1063 * - moves top-level data (index block or leaf) into the new block
1064 * - initializes new top-level, creating index that points to the
1065 * just created block
1067 static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode,
1069 struct ext4_ext_path *path,
1070 struct ext4_extent *newext)
1072 struct ext4_ext_path *curp = path;
1073 struct ext4_extent_header *neh;
1074 struct buffer_head *bh;
1075 ext4_fsblk_t newblock;
1078 newblock = ext4_ext_new_meta_block(handle, inode, path,
1079 newext, &err, flags);
1083 bh = sb_getblk(inode->i_sb, newblock);
1086 ext4_std_error(inode->i_sb, err);
1091 err = ext4_journal_get_create_access(handle, bh);
1097 /* move top-level index/leaf into new block */
1098 memmove(bh->b_data, curp->p_hdr, sizeof(EXT4_I(inode)->i_data));
1100 /* set size of new block */
1101 neh = ext_block_hdr(bh);
1102 /* old root could have indexes or leaves
1103 * so calculate e_max right way */
1104 if (ext_depth(inode))
1105 neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode, 0));
1107 neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode, 0));
1108 neh->eh_magic = EXT4_EXT_MAGIC;
1109 set_buffer_uptodate(bh);
1112 err = ext4_handle_dirty_metadata(handle, inode, bh);
1116 /* create index in new top-level index: num,max,pointer */
1117 err = ext4_ext_get_access(handle, inode, curp);
1121 curp->p_hdr->eh_magic = EXT4_EXT_MAGIC;
1122 curp->p_hdr->eh_max = cpu_to_le16(ext4_ext_space_root_idx(inode, 0));
1123 curp->p_hdr->eh_entries = cpu_to_le16(1);
1124 curp->p_idx = EXT_FIRST_INDEX(curp->p_hdr);
1126 if (path[0].p_hdr->eh_depth)
1127 curp->p_idx->ei_block =
1128 EXT_FIRST_INDEX(path[0].p_hdr)->ei_block;
1130 curp->p_idx->ei_block =
1131 EXT_FIRST_EXTENT(path[0].p_hdr)->ee_block;
1132 ext4_idx_store_pblock(curp->p_idx, newblock);
1134 neh = ext_inode_hdr(inode);
1135 ext_debug("new root: num %d(%d), lblock %d, ptr %llu\n",
1136 le16_to_cpu(neh->eh_entries), le16_to_cpu(neh->eh_max),
1137 le32_to_cpu(EXT_FIRST_INDEX(neh)->ei_block),
1138 ext4_idx_pblock(EXT_FIRST_INDEX(neh)));
1140 neh->eh_depth = cpu_to_le16(path->p_depth + 1);
1141 err = ext4_ext_dirty(handle, inode, curp);
1149 * ext4_ext_create_new_leaf:
1150 * finds empty index and adds new leaf.
1151 * if no free index is found, then it requests in-depth growing.
1153 static int ext4_ext_create_new_leaf(handle_t *handle, struct inode *inode,
1155 struct ext4_ext_path *path,
1156 struct ext4_extent *newext)
1158 struct ext4_ext_path *curp;
1159 int depth, i, err = 0;
1162 i = depth = ext_depth(inode);
1164 /* walk up to the tree and look for free index entry */
1165 curp = path + depth;
1166 while (i > 0 && !EXT_HAS_FREE_INDEX(curp)) {
1171 /* we use already allocated block for index block,
1172 * so subsequent data blocks should be contiguous */
1173 if (EXT_HAS_FREE_INDEX(curp)) {
1174 /* if we found index with free entry, then use that
1175 * entry: create all needed subtree and add new leaf */
1176 err = ext4_ext_split(handle, inode, flags, path, newext, i);
1181 ext4_ext_drop_refs(path);
1182 path = ext4_ext_find_extent(inode,
1183 (ext4_lblk_t)le32_to_cpu(newext->ee_block),
1186 err = PTR_ERR(path);
1188 /* tree is full, time to grow in depth */
1189 err = ext4_ext_grow_indepth(handle, inode, flags,
1195 ext4_ext_drop_refs(path);
1196 path = ext4_ext_find_extent(inode,
1197 (ext4_lblk_t)le32_to_cpu(newext->ee_block),
1200 err = PTR_ERR(path);
1205 * only first (depth 0 -> 1) produces free space;
1206 * in all other cases we have to split the grown tree
1208 depth = ext_depth(inode);
1209 if (path[depth].p_hdr->eh_entries == path[depth].p_hdr->eh_max) {
1210 /* now we need to split */
1220 * search the closest allocated block to the left for *logical
1221 * and returns it at @logical + it's physical address at @phys
1222 * if *logical is the smallest allocated block, the function
1223 * returns 0 at @phys
1224 * return value contains 0 (success) or error code
1226 static int ext4_ext_search_left(struct inode *inode,
1227 struct ext4_ext_path *path,
1228 ext4_lblk_t *logical, ext4_fsblk_t *phys)
1230 struct ext4_extent_idx *ix;
1231 struct ext4_extent *ex;
1234 if (unlikely(path == NULL)) {
1235 EXT4_ERROR_INODE(inode, "path == NULL *logical %d!", *logical);
1238 depth = path->p_depth;
1241 if (depth == 0 && path->p_ext == NULL)
1244 /* usually extent in the path covers blocks smaller
1245 * then *logical, but it can be that extent is the
1246 * first one in the file */
1248 ex = path[depth].p_ext;
1249 ee_len = ext4_ext_get_actual_len(ex);
1250 if (*logical < le32_to_cpu(ex->ee_block)) {
1251 if (unlikely(EXT_FIRST_EXTENT(path[depth].p_hdr) != ex)) {
1252 EXT4_ERROR_INODE(inode,
1253 "EXT_FIRST_EXTENT != ex *logical %d ee_block %d!",
1254 *logical, le32_to_cpu(ex->ee_block));
1257 while (--depth >= 0) {
1258 ix = path[depth].p_idx;
1259 if (unlikely(ix != EXT_FIRST_INDEX(path[depth].p_hdr))) {
1260 EXT4_ERROR_INODE(inode,
1261 "ix (%d) != EXT_FIRST_INDEX (%d) (depth %d)!",
1262 ix != NULL ? ix->ei_block : 0,
1263 EXT_FIRST_INDEX(path[depth].p_hdr) != NULL ?
1264 EXT_FIRST_INDEX(path[depth].p_hdr)->ei_block : 0,
1272 if (unlikely(*logical < (le32_to_cpu(ex->ee_block) + ee_len))) {
1273 EXT4_ERROR_INODE(inode,
1274 "logical %d < ee_block %d + ee_len %d!",
1275 *logical, le32_to_cpu(ex->ee_block), ee_len);
1279 *logical = le32_to_cpu(ex->ee_block) + ee_len - 1;
1280 *phys = ext4_ext_pblock(ex) + ee_len - 1;
1285 * search the closest allocated block to the right for *logical
1286 * and returns it at @logical + it's physical address at @phys
1287 * if *logical is the smallest allocated block, the function
1288 * returns 0 at @phys
1289 * return value contains 0 (success) or error code
1291 static int ext4_ext_search_right(struct inode *inode,
1292 struct ext4_ext_path *path,
1293 ext4_lblk_t *logical, ext4_fsblk_t *phys)
1295 struct buffer_head *bh = NULL;
1296 struct ext4_extent_header *eh;
1297 struct ext4_extent_idx *ix;
1298 struct ext4_extent *ex;
1300 int depth; /* Note, NOT eh_depth; depth from top of tree */
1303 if (unlikely(path == NULL)) {
1304 EXT4_ERROR_INODE(inode, "path == NULL *logical %d!", *logical);
1307 depth = path->p_depth;
1310 if (depth == 0 && path->p_ext == NULL)
1313 /* usually extent in the path covers blocks smaller
1314 * then *logical, but it can be that extent is the
1315 * first one in the file */
1317 ex = path[depth].p_ext;
1318 ee_len = ext4_ext_get_actual_len(ex);
1319 if (*logical < le32_to_cpu(ex->ee_block)) {
1320 if (unlikely(EXT_FIRST_EXTENT(path[depth].p_hdr) != ex)) {
1321 EXT4_ERROR_INODE(inode,
1322 "first_extent(path[%d].p_hdr) != ex",
1326 while (--depth >= 0) {
1327 ix = path[depth].p_idx;
1328 if (unlikely(ix != EXT_FIRST_INDEX(path[depth].p_hdr))) {
1329 EXT4_ERROR_INODE(inode,
1330 "ix != EXT_FIRST_INDEX *logical %d!",
1335 *logical = le32_to_cpu(ex->ee_block);
1336 *phys = ext4_ext_pblock(ex);
1340 if (unlikely(*logical < (le32_to_cpu(ex->ee_block) + ee_len))) {
1341 EXT4_ERROR_INODE(inode,
1342 "logical %d < ee_block %d + ee_len %d!",
1343 *logical, le32_to_cpu(ex->ee_block), ee_len);
1347 if (ex != EXT_LAST_EXTENT(path[depth].p_hdr)) {
1348 /* next allocated block in this leaf */
1350 *logical = le32_to_cpu(ex->ee_block);
1351 *phys = ext4_ext_pblock(ex);
1355 /* go up and search for index to the right */
1356 while (--depth >= 0) {
1357 ix = path[depth].p_idx;
1358 if (ix != EXT_LAST_INDEX(path[depth].p_hdr))
1362 /* we've gone up to the root and found no index to the right */
1366 /* we've found index to the right, let's
1367 * follow it and find the closest allocated
1368 * block to the right */
1370 block = ext4_idx_pblock(ix);
1371 while (++depth < path->p_depth) {
1372 bh = sb_bread(inode->i_sb, block);
1375 eh = ext_block_hdr(bh);
1376 /* subtract from p_depth to get proper eh_depth */
1377 if (ext4_ext_check(inode, eh, path->p_depth - depth)) {
1381 ix = EXT_FIRST_INDEX(eh);
1382 block = ext4_idx_pblock(ix);
1386 bh = sb_bread(inode->i_sb, block);
1389 eh = ext_block_hdr(bh);
1390 if (ext4_ext_check(inode, eh, path->p_depth - depth)) {
1394 ex = EXT_FIRST_EXTENT(eh);
1395 *logical = le32_to_cpu(ex->ee_block);
1396 *phys = ext4_ext_pblock(ex);
1402 * ext4_ext_next_allocated_block:
1403 * returns allocated block in subsequent extent or EXT_MAX_BLOCK.
1404 * NOTE: it considers block number from index entry as
1405 * allocated block. Thus, index entries have to be consistent
1409 ext4_ext_next_allocated_block(struct ext4_ext_path *path)
1413 BUG_ON(path == NULL);
1414 depth = path->p_depth;
1416 if (depth == 0 && path->p_ext == NULL)
1417 return EXT_MAX_BLOCK;
1419 while (depth >= 0) {
1420 if (depth == path->p_depth) {
1422 if (path[depth].p_ext !=
1423 EXT_LAST_EXTENT(path[depth].p_hdr))
1424 return le32_to_cpu(path[depth].p_ext[1].ee_block);
1427 if (path[depth].p_idx !=
1428 EXT_LAST_INDEX(path[depth].p_hdr))
1429 return le32_to_cpu(path[depth].p_idx[1].ei_block);
1434 return EXT_MAX_BLOCK;
1438 * ext4_ext_next_leaf_block:
1439 * returns first allocated block from next leaf or EXT_MAX_BLOCK
1441 static ext4_lblk_t ext4_ext_next_leaf_block(struct inode *inode,
1442 struct ext4_ext_path *path)
1446 BUG_ON(path == NULL);
1447 depth = path->p_depth;
1449 /* zero-tree has no leaf blocks at all */
1451 return EXT_MAX_BLOCK;
1453 /* go to index block */
1456 while (depth >= 0) {
1457 if (path[depth].p_idx !=
1458 EXT_LAST_INDEX(path[depth].p_hdr))
1459 return (ext4_lblk_t)
1460 le32_to_cpu(path[depth].p_idx[1].ei_block);
1464 return EXT_MAX_BLOCK;
1468 * ext4_ext_correct_indexes:
1469 * if leaf gets modified and modified extent is first in the leaf,
1470 * then we have to correct all indexes above.
1471 * TODO: do we need to correct tree in all cases?
1473 static int ext4_ext_correct_indexes(handle_t *handle, struct inode *inode,
1474 struct ext4_ext_path *path)
1476 struct ext4_extent_header *eh;
1477 int depth = ext_depth(inode);
1478 struct ext4_extent *ex;
1482 eh = path[depth].p_hdr;
1483 ex = path[depth].p_ext;
1485 if (unlikely(ex == NULL || eh == NULL)) {
1486 EXT4_ERROR_INODE(inode,
1487 "ex %p == NULL or eh %p == NULL", ex, eh);
1492 /* there is no tree at all */
1496 if (ex != EXT_FIRST_EXTENT(eh)) {
1497 /* we correct tree if first leaf got modified only */
1502 * TODO: we need correction if border is smaller than current one
1505 border = path[depth].p_ext->ee_block;
1506 err = ext4_ext_get_access(handle, inode, path + k);
1509 path[k].p_idx->ei_block = border;
1510 err = ext4_ext_dirty(handle, inode, path + k);
1515 /* change all left-side indexes */
1516 if (path[k+1].p_idx != EXT_FIRST_INDEX(path[k+1].p_hdr))
1518 err = ext4_ext_get_access(handle, inode, path + k);
1521 path[k].p_idx->ei_block = border;
1522 err = ext4_ext_dirty(handle, inode, path + k);
1531 ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1,
1532 struct ext4_extent *ex2)
1534 unsigned short ext1_ee_len, ext2_ee_len, max_len;
1537 * Make sure that either both extents are uninitialized, or
1540 if (ext4_ext_is_uninitialized(ex1) ^ ext4_ext_is_uninitialized(ex2))
1543 if (ext4_ext_is_uninitialized(ex1))
1544 max_len = EXT_UNINIT_MAX_LEN;
1546 max_len = EXT_INIT_MAX_LEN;
1548 ext1_ee_len = ext4_ext_get_actual_len(ex1);
1549 ext2_ee_len = ext4_ext_get_actual_len(ex2);
1551 if (le32_to_cpu(ex1->ee_block) + ext1_ee_len !=
1552 le32_to_cpu(ex2->ee_block))
1556 * To allow future support for preallocated extents to be added
1557 * as an RO_COMPAT feature, refuse to merge to extents if
1558 * this can result in the top bit of ee_len being set.
1560 if (ext1_ee_len + ext2_ee_len > max_len)
1562 #ifdef AGGRESSIVE_TEST
1563 if (ext1_ee_len >= 4)
1567 if (ext4_ext_pblock(ex1) + ext1_ee_len == ext4_ext_pblock(ex2))
1573 * This function tries to merge the "ex" extent to the next extent in the tree.
1574 * It always tries to merge towards right. If you want to merge towards
1575 * left, pass "ex - 1" as argument instead of "ex".
1576 * Returns 0 if the extents (ex and ex+1) were _not_ merged and returns
1577 * 1 if they got merged.
1579 static int ext4_ext_try_to_merge_right(struct inode *inode,
1580 struct ext4_ext_path *path,
1581 struct ext4_extent *ex)
1583 struct ext4_extent_header *eh;
1584 unsigned int depth, len;
1586 int uninitialized = 0;
1588 depth = ext_depth(inode);
1589 BUG_ON(path[depth].p_hdr == NULL);
1590 eh = path[depth].p_hdr;
1592 while (ex < EXT_LAST_EXTENT(eh)) {
1593 if (!ext4_can_extents_be_merged(inode, ex, ex + 1))
1595 /* merge with next extent! */
1596 if (ext4_ext_is_uninitialized(ex))
1598 ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
1599 + ext4_ext_get_actual_len(ex + 1));
1601 ext4_ext_mark_uninitialized(ex);
1603 if (ex + 1 < EXT_LAST_EXTENT(eh)) {
1604 len = (EXT_LAST_EXTENT(eh) - ex - 1)
1605 * sizeof(struct ext4_extent);
1606 memmove(ex + 1, ex + 2, len);
1608 le16_add_cpu(&eh->eh_entries, -1);
1610 WARN_ON(eh->eh_entries == 0);
1611 if (!eh->eh_entries)
1612 EXT4_ERROR_INODE(inode, "eh->eh_entries = 0!");
1619 * This function tries to merge the @ex extent to neighbours in the tree.
1620 * return 1 if merge left else 0.
1622 static int ext4_ext_try_to_merge(struct inode *inode,
1623 struct ext4_ext_path *path,
1624 struct ext4_extent *ex) {
1625 struct ext4_extent_header *eh;
1630 depth = ext_depth(inode);
1631 BUG_ON(path[depth].p_hdr == NULL);
1632 eh = path[depth].p_hdr;
1634 if (ex > EXT_FIRST_EXTENT(eh))
1635 merge_done = ext4_ext_try_to_merge_right(inode, path, ex - 1);
1638 ret = ext4_ext_try_to_merge_right(inode, path, ex);
1644 * check if a portion of the "newext" extent overlaps with an
1647 * If there is an overlap discovered, it updates the length of the newext
1648 * such that there will be no overlap, and then returns 1.
1649 * If there is no overlap found, it returns 0.
1651 static unsigned int ext4_ext_check_overlap(struct inode *inode,
1652 struct ext4_extent *newext,
1653 struct ext4_ext_path *path)
1656 unsigned int depth, len1;
1657 unsigned int ret = 0;
1659 b1 = le32_to_cpu(newext->ee_block);
1660 len1 = ext4_ext_get_actual_len(newext);
1661 depth = ext_depth(inode);
1662 if (!path[depth].p_ext)
1664 b2 = le32_to_cpu(path[depth].p_ext->ee_block);
1667 * get the next allocated block if the extent in the path
1668 * is before the requested block(s)
1671 b2 = ext4_ext_next_allocated_block(path);
1672 if (b2 == EXT_MAX_BLOCK)
1676 /* check for wrap through zero on extent logical start block*/
1677 if (b1 + len1 < b1) {
1678 len1 = EXT_MAX_BLOCK - b1;
1679 newext->ee_len = cpu_to_le16(len1);
1683 /* check for overlap */
1684 if (b1 + len1 > b2) {
1685 newext->ee_len = cpu_to_le16(b2 - b1);
1693 * ext4_ext_insert_extent:
1694 * tries to merge requsted extent into the existing extent or
1695 * inserts requested extent as new one into the tree,
1696 * creating new leaf in the no-space case.
1698 int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
1699 struct ext4_ext_path *path,
1700 struct ext4_extent *newext, int flag)
1702 struct ext4_extent_header *eh;
1703 struct ext4_extent *ex, *fex;
1704 struct ext4_extent *nearex; /* nearest extent */
1705 struct ext4_ext_path *npath = NULL;
1706 int depth, len, err;
1708 unsigned uninitialized = 0;
1711 if (unlikely(ext4_ext_get_actual_len(newext) == 0)) {
1712 EXT4_ERROR_INODE(inode, "ext4_ext_get_actual_len(newext) == 0");
1715 depth = ext_depth(inode);
1716 ex = path[depth].p_ext;
1717 if (unlikely(path[depth].p_hdr == NULL)) {
1718 EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
1722 /* try to insert block into found extent and return */
1723 if (ex && !(flag & EXT4_GET_BLOCKS_PRE_IO)
1724 && ext4_can_extents_be_merged(inode, ex, newext)) {
1725 ext_debug("append [%d]%d block to %d:[%d]%d (from %llu)\n",
1726 ext4_ext_is_uninitialized(newext),
1727 ext4_ext_get_actual_len(newext),
1728 le32_to_cpu(ex->ee_block),
1729 ext4_ext_is_uninitialized(ex),
1730 ext4_ext_get_actual_len(ex),
1731 ext4_ext_pblock(ex));
1732 err = ext4_ext_get_access(handle, inode, path + depth);
1737 * ext4_can_extents_be_merged should have checked that either
1738 * both extents are uninitialized, or both aren't. Thus we
1739 * need to check only one of them here.
1741 if (ext4_ext_is_uninitialized(ex))
1743 ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
1744 + ext4_ext_get_actual_len(newext));
1746 ext4_ext_mark_uninitialized(ex);
1747 eh = path[depth].p_hdr;
1753 depth = ext_depth(inode);
1754 eh = path[depth].p_hdr;
1755 if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max))
1758 /* probably next leaf has space for us? */
1759 fex = EXT_LAST_EXTENT(eh);
1760 next = ext4_ext_next_leaf_block(inode, path);
1761 if (le32_to_cpu(newext->ee_block) > le32_to_cpu(fex->ee_block)
1762 && next != EXT_MAX_BLOCK) {
1763 ext_debug("next leaf block - %d\n", next);
1764 BUG_ON(npath != NULL);
1765 npath = ext4_ext_find_extent(inode, next, NULL);
1767 return PTR_ERR(npath);
1768 BUG_ON(npath->p_depth != path->p_depth);
1769 eh = npath[depth].p_hdr;
1770 if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max)) {
1771 ext_debug("next leaf isn't full(%d)\n",
1772 le16_to_cpu(eh->eh_entries));
1776 ext_debug("next leaf has no free space(%d,%d)\n",
1777 le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max));
1781 * There is no free space in the found leaf.
1782 * We're gonna add a new leaf in the tree.
1784 if (flag & EXT4_GET_BLOCKS_PUNCH_OUT_EXT)
1785 flags = EXT4_MB_USE_ROOT_BLOCKS;
1786 err = ext4_ext_create_new_leaf(handle, inode, flags, path, newext);
1789 depth = ext_depth(inode);
1790 eh = path[depth].p_hdr;
1793 nearex = path[depth].p_ext;
1795 err = ext4_ext_get_access(handle, inode, path + depth);
1800 /* there is no extent in this leaf, create first one */
1801 ext_debug("first extent in the leaf: %d:%llu:[%d]%d\n",
1802 le32_to_cpu(newext->ee_block),
1803 ext4_ext_pblock(newext),
1804 ext4_ext_is_uninitialized(newext),
1805 ext4_ext_get_actual_len(newext));
1806 path[depth].p_ext = EXT_FIRST_EXTENT(eh);
1807 } else if (le32_to_cpu(newext->ee_block)
1808 > le32_to_cpu(nearex->ee_block)) {
1809 /* BUG_ON(newext->ee_block == nearex->ee_block); */
1810 if (nearex != EXT_LAST_EXTENT(eh)) {
1811 len = EXT_MAX_EXTENT(eh) - nearex;
1812 len = (len - 1) * sizeof(struct ext4_extent);
1813 len = len < 0 ? 0 : len;
1814 ext_debug("insert %d:%llu:[%d]%d after: nearest 0x%p, "
1815 "move %d from 0x%p to 0x%p\n",
1816 le32_to_cpu(newext->ee_block),
1817 ext4_ext_pblock(newext),
1818 ext4_ext_is_uninitialized(newext),
1819 ext4_ext_get_actual_len(newext),
1820 nearex, len, nearex + 1, nearex + 2);
1821 memmove(nearex + 2, nearex + 1, len);
1823 path[depth].p_ext = nearex + 1;
1825 BUG_ON(newext->ee_block == nearex->ee_block);
1826 len = (EXT_MAX_EXTENT(eh) - nearex) * sizeof(struct ext4_extent);
1827 len = len < 0 ? 0 : len;
1828 ext_debug("insert %d:%llu:[%d]%d before: nearest 0x%p, "
1829 "move %d from 0x%p to 0x%p\n",
1830 le32_to_cpu(newext->ee_block),
1831 ext4_ext_pblock(newext),
1832 ext4_ext_is_uninitialized(newext),
1833 ext4_ext_get_actual_len(newext),
1834 nearex, len, nearex + 1, nearex + 2);
1835 memmove(nearex + 1, nearex, len);
1836 path[depth].p_ext = nearex;
1839 le16_add_cpu(&eh->eh_entries, 1);
1840 nearex = path[depth].p_ext;
1841 nearex->ee_block = newext->ee_block;
1842 ext4_ext_store_pblock(nearex, ext4_ext_pblock(newext));
1843 nearex->ee_len = newext->ee_len;
1846 /* try to merge extents to the right */
1847 if (!(flag & EXT4_GET_BLOCKS_PRE_IO))
1848 ext4_ext_try_to_merge(inode, path, nearex);
1850 /* try to merge extents to the left */
1852 /* time to correct all indexes above */
1853 err = ext4_ext_correct_indexes(handle, inode, path);
1857 err = ext4_ext_dirty(handle, inode, path + depth);
1861 ext4_ext_drop_refs(npath);
1864 ext4_ext_invalidate_cache(inode);
1868 static int ext4_ext_walk_space(struct inode *inode, ext4_lblk_t block,
1869 ext4_lblk_t num, ext_prepare_callback func,
1872 struct ext4_ext_path *path = NULL;
1873 struct ext4_ext_cache cbex;
1874 struct ext4_extent *ex;
1875 ext4_lblk_t next, start = 0, end = 0;
1876 ext4_lblk_t last = block + num;
1877 int depth, exists, err = 0;
1879 BUG_ON(func == NULL);
1880 BUG_ON(inode == NULL);
1882 while (block < last && block != EXT_MAX_BLOCK) {
1884 /* find extent for this block */
1885 down_read(&EXT4_I(inode)->i_data_sem);
1886 path = ext4_ext_find_extent(inode, block, path);
1887 up_read(&EXT4_I(inode)->i_data_sem);
1889 err = PTR_ERR(path);
1894 depth = ext_depth(inode);
1895 if (unlikely(path[depth].p_hdr == NULL)) {
1896 EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
1900 ex = path[depth].p_ext;
1901 next = ext4_ext_next_allocated_block(path);
1905 /* there is no extent yet, so try to allocate
1906 * all requested space */
1909 } else if (le32_to_cpu(ex->ee_block) > block) {
1910 /* need to allocate space before found extent */
1912 end = le32_to_cpu(ex->ee_block);
1913 if (block + num < end)
1915 } else if (block >= le32_to_cpu(ex->ee_block)
1916 + ext4_ext_get_actual_len(ex)) {
1917 /* need to allocate space after found extent */
1922 } else if (block >= le32_to_cpu(ex->ee_block)) {
1924 * some part of requested space is covered
1928 end = le32_to_cpu(ex->ee_block)
1929 + ext4_ext_get_actual_len(ex);
1930 if (block + num < end)
1936 BUG_ON(end <= start);
1939 cbex.ec_block = start;
1940 cbex.ec_len = end - start;
1943 cbex.ec_block = le32_to_cpu(ex->ee_block);
1944 cbex.ec_len = ext4_ext_get_actual_len(ex);
1945 cbex.ec_start = ext4_ext_pblock(ex);
1948 if (unlikely(cbex.ec_len == 0)) {
1949 EXT4_ERROR_INODE(inode, "cbex.ec_len == 0");
1953 err = func(inode, path, &cbex, ex, cbdata);
1954 ext4_ext_drop_refs(path);
1959 if (err == EXT_REPEAT)
1961 else if (err == EXT_BREAK) {
1966 if (ext_depth(inode) != depth) {
1967 /* depth was changed. we have to realloc path */
1972 block = cbex.ec_block + cbex.ec_len;
1976 ext4_ext_drop_refs(path);
1984 ext4_ext_put_in_cache(struct inode *inode, ext4_lblk_t block,
1985 __u32 len, ext4_fsblk_t start)
1987 struct ext4_ext_cache *cex;
1989 spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
1990 cex = &EXT4_I(inode)->i_cached_extent;
1991 cex->ec_block = block;
1993 cex->ec_start = start;
1994 spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
1998 * ext4_ext_put_gap_in_cache:
1999 * calculate boundaries of the gap that the requested block fits into
2000 * and cache this gap
2003 ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path,
2006 int depth = ext_depth(inode);
2009 struct ext4_extent *ex;
2011 ex = path[depth].p_ext;
2013 /* there is no extent yet, so gap is [0;-] */
2015 len = EXT_MAX_BLOCK;
2016 ext_debug("cache gap(whole file):");
2017 } else if (block < le32_to_cpu(ex->ee_block)) {
2019 len = le32_to_cpu(ex->ee_block) - block;
2020 ext_debug("cache gap(before): %u [%u:%u]",
2022 le32_to_cpu(ex->ee_block),
2023 ext4_ext_get_actual_len(ex));
2024 } else if (block >= le32_to_cpu(ex->ee_block)
2025 + ext4_ext_get_actual_len(ex)) {
2027 lblock = le32_to_cpu(ex->ee_block)
2028 + ext4_ext_get_actual_len(ex);
2030 next = ext4_ext_next_allocated_block(path);
2031 ext_debug("cache gap(after): [%u:%u] %u",
2032 le32_to_cpu(ex->ee_block),
2033 ext4_ext_get_actual_len(ex),
2035 BUG_ON(next == lblock);
2036 len = next - lblock;
2042 ext_debug(" -> %u:%lu\n", lblock, len);
2043 ext4_ext_put_in_cache(inode, lblock, len, 0);
2047 * ext4_ext_in_cache()
2048 * Checks to see if the given block is in the cache.
2049 * If it is, the cached extent is stored in the given
2050 * cache extent pointer. If the cached extent is a hole,
2051 * this routine should be used instead of
2052 * ext4_ext_in_cache if the calling function needs to
2053 * know the size of the hole.
2055 * @inode: The files inode
2056 * @block: The block to look for in the cache
2057 * @ex: Pointer where the cached extent will be stored
2058 * if it contains block
2060 * Return 0 if cache is invalid; 1 if the cache is valid
2062 static int ext4_ext_check_cache(struct inode *inode, ext4_lblk_t block,
2063 struct ext4_ext_cache *ex){
2064 struct ext4_ext_cache *cex;
2065 struct ext4_sb_info *sbi;
2069 * We borrow i_block_reservation_lock to protect i_cached_extent
2071 spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
2072 cex = &EXT4_I(inode)->i_cached_extent;
2073 sbi = EXT4_SB(inode->i_sb);
2075 /* has cache valid data? */
2076 if (cex->ec_len == 0)
2079 if (in_range(block, cex->ec_block, cex->ec_len)) {
2080 memcpy(ex, cex, sizeof(struct ext4_ext_cache));
2081 ext_debug("%u cached by %u:%u:%llu\n",
2083 cex->ec_block, cex->ec_len, cex->ec_start);
2088 sbi->extent_cache_misses++;
2090 sbi->extent_cache_hits++;
2091 spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
2096 * ext4_ext_in_cache()
2097 * Checks to see if the given block is in the cache.
2098 * If it is, the cached extent is stored in the given
2101 * @inode: The files inode
2102 * @block: The block to look for in the cache
2103 * @ex: Pointer where the cached extent will be stored
2104 * if it contains block
2106 * Return 0 if cache is invalid; 1 if the cache is valid
2109 ext4_ext_in_cache(struct inode *inode, ext4_lblk_t block,
2110 struct ext4_extent *ex)
2112 struct ext4_ext_cache cex;
2115 if (ext4_ext_check_cache(inode, block, &cex)) {
2116 ex->ee_block = cpu_to_le32(cex.ec_block);
2117 ext4_ext_store_pblock(ex, cex.ec_start);
2118 ex->ee_len = cpu_to_le16(cex.ec_len);
2128 * removes index from the index block.
2129 * It's used in truncate case only, thus all requests are for
2130 * last index in the block only.
2132 static int ext4_ext_rm_idx(handle_t *handle, struct inode *inode,
2133 struct ext4_ext_path *path)
2138 /* free index block */
2140 leaf = ext4_idx_pblock(path->p_idx);
2141 if (unlikely(path->p_hdr->eh_entries == 0)) {
2142 EXT4_ERROR_INODE(inode, "path->p_hdr->eh_entries == 0");
2145 err = ext4_ext_get_access(handle, inode, path);
2148 le16_add_cpu(&path->p_hdr->eh_entries, -1);
2149 err = ext4_ext_dirty(handle, inode, path);
2152 ext_debug("index is empty, remove it, free block %llu\n", leaf);
2153 ext4_free_blocks(handle, inode, NULL, leaf, 1,
2154 EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
2159 * ext4_ext_calc_credits_for_single_extent:
2160 * This routine returns max. credits that needed to insert an extent
2161 * to the extent tree.
2162 * When pass the actual path, the caller should calculate credits
2165 int ext4_ext_calc_credits_for_single_extent(struct inode *inode, int nrblocks,
2166 struct ext4_ext_path *path)
2169 int depth = ext_depth(inode);
2172 /* probably there is space in leaf? */
2173 if (le16_to_cpu(path[depth].p_hdr->eh_entries)
2174 < le16_to_cpu(path[depth].p_hdr->eh_max)) {
2177 * There are some space in the leaf tree, no
2178 * need to account for leaf block credit
2180 * bitmaps and block group descriptor blocks
2181 * and other metadat blocks still need to be
2184 /* 1 bitmap, 1 block group descriptor */
2185 ret = 2 + EXT4_META_TRANS_BLOCKS(inode->i_sb);
2190 return ext4_chunk_trans_blocks(inode, nrblocks);
2194 * How many index/leaf blocks need to change/allocate to modify nrblocks?
2196 * if nrblocks are fit in a single extent (chunk flag is 1), then
2197 * in the worse case, each tree level index/leaf need to be changed
2198 * if the tree split due to insert a new extent, then the old tree
2199 * index/leaf need to be updated too
2201 * If the nrblocks are discontiguous, they could cause
2202 * the whole tree split more than once, but this is really rare.
2204 int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks, int chunk)
2207 int depth = ext_depth(inode);
2217 static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
2218 struct ext4_extent *ex,
2219 ext4_lblk_t from, ext4_lblk_t to)
2221 unsigned short ee_len = ext4_ext_get_actual_len(ex);
2222 int flags = EXT4_FREE_BLOCKS_FORGET;
2224 if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
2225 flags |= EXT4_FREE_BLOCKS_METADATA;
2226 #ifdef EXTENTS_STATS
2228 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
2229 spin_lock(&sbi->s_ext_stats_lock);
2230 sbi->s_ext_blocks += ee_len;
2231 sbi->s_ext_extents++;
2232 if (ee_len < sbi->s_ext_min)
2233 sbi->s_ext_min = ee_len;
2234 if (ee_len > sbi->s_ext_max)
2235 sbi->s_ext_max = ee_len;
2236 if (ext_depth(inode) > sbi->s_depth_max)
2237 sbi->s_depth_max = ext_depth(inode);
2238 spin_unlock(&sbi->s_ext_stats_lock);
2241 if (from >= le32_to_cpu(ex->ee_block)
2242 && to == le32_to_cpu(ex->ee_block) + ee_len - 1) {
2247 num = le32_to_cpu(ex->ee_block) + ee_len - from;
2248 start = ext4_ext_pblock(ex) + ee_len - num;
2249 ext_debug("free last %u blocks starting %llu\n", num, start);
2250 ext4_free_blocks(handle, inode, NULL, start, num, flags);
2251 } else if (from == le32_to_cpu(ex->ee_block)
2252 && to <= le32_to_cpu(ex->ee_block) + ee_len - 1) {
2258 start = ext4_ext_pblock(ex);
2260 ext_debug("free first %u blocks starting %llu\n", num, start);
2261 ext4_free_blocks(handle, inode, 0, start, num, flags);
2264 printk(KERN_INFO "strange request: removal(2) "
2265 "%u-%u from %u:%u\n",
2266 from, to, le32_to_cpu(ex->ee_block), ee_len);
2273 * ext4_ext_rm_leaf() Removes the extents associated with the
2274 * blocks appearing between "start" and "end", and splits the extents
2275 * if "start" and "end" appear in the same extent
2277 * @handle: The journal handle
2278 * @inode: The files inode
2279 * @path: The path to the leaf
2280 * @start: The first block to remove
2281 * @end: The last block to remove
2284 ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
2285 struct ext4_ext_path *path, ext4_lblk_t start,
2288 int err = 0, correct_index = 0;
2289 int depth = ext_depth(inode), credits;
2290 struct ext4_extent_header *eh;
2291 ext4_lblk_t a, b, block;
2293 ext4_lblk_t ex_ee_block;
2294 unsigned short ex_ee_len;
2295 unsigned uninitialized = 0;
2296 struct ext4_extent *ex;
2297 struct ext4_map_blocks map;
2299 /* the header must be checked already in ext4_ext_remove_space() */
2300 ext_debug("truncate since %u in leaf\n", start);
2301 if (!path[depth].p_hdr)
2302 path[depth].p_hdr = ext_block_hdr(path[depth].p_bh);
2303 eh = path[depth].p_hdr;
2304 if (unlikely(path[depth].p_hdr == NULL)) {
2305 EXT4_ERROR_INODE(inode, "path[%d].p_hdr == NULL", depth);
2308 /* find where to start removing */
2309 ex = EXT_LAST_EXTENT(eh);
2311 ex_ee_block = le32_to_cpu(ex->ee_block);
2312 ex_ee_len = ext4_ext_get_actual_len(ex);
2314 while (ex >= EXT_FIRST_EXTENT(eh) &&
2315 ex_ee_block + ex_ee_len > start) {
2317 if (ext4_ext_is_uninitialized(ex))
2322 ext_debug("remove ext %u:[%d]%d\n", ex_ee_block,
2323 uninitialized, ex_ee_len);
2324 path[depth].p_ext = ex;
2326 a = ex_ee_block > start ? ex_ee_block : start;
2327 b = ex_ee_block+ex_ee_len - 1 < end ?
2328 ex_ee_block+ex_ee_len - 1 : end;
2330 ext_debug(" border %u:%u\n", a, b);
2332 /* If this extent is beyond the end of the hole, skip it */
2333 if (end <= ex_ee_block) {
2335 ex_ee_block = le32_to_cpu(ex->ee_block);
2336 ex_ee_len = ext4_ext_get_actual_len(ex);
2338 } else if (a != ex_ee_block &&
2339 b != ex_ee_block + ex_ee_len - 1) {
2341 * If this is a truncate, then this condition should
2342 * never happen because at least one of the end points
2343 * needs to be on the edge of the extent.
2345 if (end == EXT_MAX_BLOCK) {
2346 ext_debug(" bad truncate %u:%u\n",
2354 * else this is a hole punch, so the extent needs to
2355 * be split since neither edge of the hole is on the
2359 map.m_pblk = ext4_ext_pblock(ex);
2360 map.m_lblk = ex_ee_block;
2361 map.m_len = b - ex_ee_block;
2363 err = ext4_split_extent(handle,
2364 inode, path, &map, 0,
2365 EXT4_GET_BLOCKS_PUNCH_OUT_EXT |
2366 EXT4_GET_BLOCKS_PRE_IO);
2371 ex_ee_len = ext4_ext_get_actual_len(ex);
2373 b = ex_ee_block+ex_ee_len - 1 < end ?
2374 ex_ee_block+ex_ee_len - 1 : end;
2376 /* Then remove tail of this extent */
2377 block = ex_ee_block;
2380 } else if (a != ex_ee_block) {
2381 /* remove tail of the extent */
2382 block = ex_ee_block;
2384 } else if (b != ex_ee_block + ex_ee_len - 1) {
2385 /* remove head of the extent */
2387 num = ex_ee_block + ex_ee_len - b;
2390 * If this is a truncate, this condition
2391 * should never happen
2393 if (end == EXT_MAX_BLOCK) {
2394 ext_debug(" bad truncate %u:%u\n",
2400 /* remove whole extent: excellent! */
2401 block = ex_ee_block;
2403 if (a != ex_ee_block) {
2404 ext_debug(" bad truncate %u:%u\n",
2410 if (b != ex_ee_block + ex_ee_len - 1) {
2411 ext_debug(" bad truncate %u:%u\n",
2419 * 3 for leaf, sb, and inode plus 2 (bmap and group
2420 * descriptor) for each block group; assume two block
2421 * groups plus ex_ee_len/blocks_per_block_group for
2424 credits = 7 + 2*(ex_ee_len/EXT4_BLOCKS_PER_GROUP(inode->i_sb));
2425 if (ex == EXT_FIRST_EXTENT(eh)) {
2427 credits += (ext_depth(inode)) + 1;
2429 credits += EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb);
2431 err = ext4_ext_truncate_extend_restart(handle, inode, credits);
2435 err = ext4_ext_get_access(handle, inode, path + depth);
2439 err = ext4_remove_blocks(handle, inode, ex, a, b);
2444 /* this extent is removed; mark slot entirely unused */
2445 ext4_ext_store_pblock(ex, 0);
2446 } else if (block != ex_ee_block) {
2448 * If this was a head removal, then we need to update
2449 * the physical block since it is now at a different
2452 ext4_ext_store_pblock(ex, ext4_ext_pblock(ex) + (b-a));
2455 ex->ee_block = cpu_to_le32(block);
2456 ex->ee_len = cpu_to_le16(num);
2458 * Do not mark uninitialized if all the blocks in the
2459 * extent have been removed.
2461 if (uninitialized && num)
2462 ext4_ext_mark_uninitialized(ex);
2464 err = ext4_ext_dirty(handle, inode, path + depth);
2469 * If the extent was completely released,
2470 * we need to remove it from the leaf
2473 if (end != EXT_MAX_BLOCK) {
2475 * For hole punching, we need to scoot all the
2476 * extents up when an extent is removed so that
2477 * we dont have blank extents in the middle
2479 memmove(ex, ex+1, (EXT_LAST_EXTENT(eh) - ex) *
2480 sizeof(struct ext4_extent));
2482 /* Now get rid of the one at the end */
2483 memset(EXT_LAST_EXTENT(eh), 0,
2484 sizeof(struct ext4_extent));
2486 le16_add_cpu(&eh->eh_entries, -1);
2489 ext_debug("new extent: %u:%u:%llu\n", block, num,
2490 ext4_ext_pblock(ex));
2492 ex_ee_block = le32_to_cpu(ex->ee_block);
2493 ex_ee_len = ext4_ext_get_actual_len(ex);
2496 if (correct_index && eh->eh_entries)
2497 err = ext4_ext_correct_indexes(handle, inode, path);
2499 /* if this leaf is free, then we should
2500 * remove it from index block above */
2501 if (err == 0 && eh->eh_entries == 0 && path[depth].p_bh != NULL)
2502 err = ext4_ext_rm_idx(handle, inode, path + depth);
2509 * ext4_ext_more_to_rm:
2510 * returns 1 if current index has to be freed (even partial)
2513 ext4_ext_more_to_rm(struct ext4_ext_path *path)
2515 BUG_ON(path->p_idx == NULL);
2517 if (path->p_idx < EXT_FIRST_INDEX(path->p_hdr))
2521 * if truncate on deeper level happened, it wasn't partial,
2522 * so we have to consider current index for truncation
2524 if (le16_to_cpu(path->p_hdr->eh_entries) == path->p_block)
2529 static int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
2532 struct super_block *sb = inode->i_sb;
2533 int depth = ext_depth(inode);
2534 struct ext4_ext_path *path;
2538 ext_debug("truncate since %u\n", start);
2540 /* probably first extent we're gonna free will be last in block */
2541 handle = ext4_journal_start(inode, depth + 1);
2543 return PTR_ERR(handle);
2546 ext4_ext_invalidate_cache(inode);
2549 * We start scanning from right side, freeing all the blocks
2550 * after i_size and walking into the tree depth-wise.
2552 depth = ext_depth(inode);
2553 path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 1), GFP_NOFS);
2555 ext4_journal_stop(handle);
2558 path[0].p_depth = depth;
2559 path[0].p_hdr = ext_inode_hdr(inode);
2560 if (ext4_ext_check(inode, path[0].p_hdr, depth)) {
2566 while (i >= 0 && err == 0) {
2568 /* this is leaf block */
2569 err = ext4_ext_rm_leaf(handle, inode, path,
2571 /* root level has p_bh == NULL, brelse() eats this */
2572 brelse(path[i].p_bh);
2573 path[i].p_bh = NULL;
2578 /* this is index block */
2579 if (!path[i].p_hdr) {
2580 ext_debug("initialize header\n");
2581 path[i].p_hdr = ext_block_hdr(path[i].p_bh);
2584 if (!path[i].p_idx) {
2585 /* this level hasn't been touched yet */
2586 path[i].p_idx = EXT_LAST_INDEX(path[i].p_hdr);
2587 path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries)+1;
2588 ext_debug("init index ptr: hdr 0x%p, num %d\n",
2590 le16_to_cpu(path[i].p_hdr->eh_entries));
2592 /* we were already here, see at next index */
2596 ext_debug("level %d - index, first 0x%p, cur 0x%p\n",
2597 i, EXT_FIRST_INDEX(path[i].p_hdr),
2599 if (ext4_ext_more_to_rm(path + i)) {
2600 struct buffer_head *bh;
2601 /* go to the next level */
2602 ext_debug("move to level %d (block %llu)\n",
2603 i + 1, ext4_idx_pblock(path[i].p_idx));
2604 memset(path + i + 1, 0, sizeof(*path));
2605 bh = sb_bread(sb, ext4_idx_pblock(path[i].p_idx));
2607 /* should we reset i_size? */
2611 if (WARN_ON(i + 1 > depth)) {
2615 if (ext4_ext_check(inode, ext_block_hdr(bh),
2620 path[i + 1].p_bh = bh;
2622 /* save actual number of indexes since this
2623 * number is changed at the next iteration */
2624 path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries);
2627 /* we finished processing this index, go up */
2628 if (path[i].p_hdr->eh_entries == 0 && i > 0) {
2629 /* index is empty, remove it;
2630 * handle must be already prepared by the
2631 * truncatei_leaf() */
2632 err = ext4_ext_rm_idx(handle, inode, path + i);
2634 /* root level has p_bh == NULL, brelse() eats this */
2635 brelse(path[i].p_bh);
2636 path[i].p_bh = NULL;
2638 ext_debug("return to level %d\n", i);
2642 /* TODO: flexible tree reduction should be here */
2643 if (path->p_hdr->eh_entries == 0) {
2645 * truncate to zero freed all the tree,
2646 * so we need to correct eh_depth
2648 err = ext4_ext_get_access(handle, inode, path);
2650 ext_inode_hdr(inode)->eh_depth = 0;
2651 ext_inode_hdr(inode)->eh_max =
2652 cpu_to_le16(ext4_ext_space_root(inode, 0));
2653 err = ext4_ext_dirty(handle, inode, path);
2657 ext4_ext_drop_refs(path);
2661 ext4_journal_stop(handle);
2667 * called at mount time
2669 void ext4_ext_init(struct super_block *sb)
2672 * possible initialization would be here
2675 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2676 #if defined(AGGRESSIVE_TEST) || defined(CHECK_BINSEARCH) || defined(EXTENTS_STATS)
2677 printk(KERN_INFO "EXT4-fs: file extents enabled");
2678 #ifdef AGGRESSIVE_TEST
2679 printk(", aggressive tests");
2681 #ifdef CHECK_BINSEARCH
2682 printk(", check binsearch");
2684 #ifdef EXTENTS_STATS
2689 #ifdef EXTENTS_STATS
2690 spin_lock_init(&EXT4_SB(sb)->s_ext_stats_lock);
2691 EXT4_SB(sb)->s_ext_min = 1 << 30;
2692 EXT4_SB(sb)->s_ext_max = 0;
2698 * called at umount time
2700 void ext4_ext_release(struct super_block *sb)
2702 if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS))
2705 #ifdef EXTENTS_STATS
2706 if (EXT4_SB(sb)->s_ext_blocks && EXT4_SB(sb)->s_ext_extents) {
2707 struct ext4_sb_info *sbi = EXT4_SB(sb);
2708 printk(KERN_ERR "EXT4-fs: %lu blocks in %lu extents (%lu ave)\n",
2709 sbi->s_ext_blocks, sbi->s_ext_extents,
2710 sbi->s_ext_blocks / sbi->s_ext_extents);
2711 printk(KERN_ERR "EXT4-fs: extents: %lu min, %lu max, max depth %lu\n",
2712 sbi->s_ext_min, sbi->s_ext_max, sbi->s_depth_max);
2717 /* FIXME!! we need to try to merge to left or right after zero-out */
2718 static int ext4_ext_zeroout(struct inode *inode, struct ext4_extent *ex)
2720 ext4_fsblk_t ee_pblock;
2721 unsigned int ee_len;
2724 ee_len = ext4_ext_get_actual_len(ex);
2725 ee_pblock = ext4_ext_pblock(ex);
2727 ret = sb_issue_zeroout(inode->i_sb, ee_pblock, ee_len, GFP_NOFS);
2735 * used by extent splitting.
2737 #define EXT4_EXT_MAY_ZEROOUT 0x1 /* safe to zeroout if split fails \
2739 #define EXT4_EXT_MARK_UNINIT1 0x2 /* mark first half uninitialized */
2740 #define EXT4_EXT_MARK_UNINIT2 0x4 /* mark second half uninitialized */
2743 * ext4_split_extent_at() splits an extent at given block.
2745 * @handle: the journal handle
2746 * @inode: the file inode
2747 * @path: the path to the extent
2748 * @split: the logical block where the extent is splitted.
2749 * @split_flags: indicates if the extent could be zeroout if split fails, and
2750 * the states(init or uninit) of new extents.
2751 * @flags: flags used to insert new extent to extent tree.
2754 * Splits extent [a, b] into two extents [a, @split) and [@split, b], states
2755 * of which are deterimined by split_flag.
2757 * There are two cases:
2758 * a> the extent are splitted into two extent.
2759 * b> split is not needed, and just mark the extent.
2761 * return 0 on success.
2763 static int ext4_split_extent_at(handle_t *handle,
2764 struct inode *inode,
2765 struct ext4_ext_path *path,
2770 ext4_fsblk_t newblock;
2771 ext4_lblk_t ee_block;
2772 struct ext4_extent *ex, newex, orig_ex;
2773 struct ext4_extent *ex2 = NULL;
2774 unsigned int ee_len, depth;
2777 ext_debug("ext4_split_extents_at: inode %lu, logical"
2778 "block %llu\n", inode->i_ino, (unsigned long long)split);
2780 ext4_ext_show_leaf(inode, path);
2782 depth = ext_depth(inode);
2783 ex = path[depth].p_ext;
2784 ee_block = le32_to_cpu(ex->ee_block);
2785 ee_len = ext4_ext_get_actual_len(ex);
2786 newblock = split - ee_block + ext4_ext_pblock(ex);
2788 BUG_ON(split < ee_block || split >= (ee_block + ee_len));
2790 err = ext4_ext_get_access(handle, inode, path + depth);
2794 if (split == ee_block) {
2796 * case b: block @split is the block that the extent begins with
2797 * then we just change the state of the extent, and splitting
2800 if (split_flag & EXT4_EXT_MARK_UNINIT2)
2801 ext4_ext_mark_uninitialized(ex);
2803 ext4_ext_mark_initialized(ex);
2805 if (!(flags & EXT4_GET_BLOCKS_PRE_IO))
2806 ext4_ext_try_to_merge(inode, path, ex);
2808 err = ext4_ext_dirty(handle, inode, path + depth);
2813 memcpy(&orig_ex, ex, sizeof(orig_ex));
2814 ex->ee_len = cpu_to_le16(split - ee_block);
2815 if (split_flag & EXT4_EXT_MARK_UNINIT1)
2816 ext4_ext_mark_uninitialized(ex);
2819 * path may lead to new leaf, not to original leaf any more
2820 * after ext4_ext_insert_extent() returns,
2822 err = ext4_ext_dirty(handle, inode, path + depth);
2824 goto fix_extent_len;
2827 ex2->ee_block = cpu_to_le32(split);
2828 ex2->ee_len = cpu_to_le16(ee_len - (split - ee_block));
2829 ext4_ext_store_pblock(ex2, newblock);
2830 if (split_flag & EXT4_EXT_MARK_UNINIT2)
2831 ext4_ext_mark_uninitialized(ex2);
2833 err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
2834 if (err == -ENOSPC && (EXT4_EXT_MAY_ZEROOUT & split_flag)) {
2835 err = ext4_ext_zeroout(inode, &orig_ex);
2837 goto fix_extent_len;
2838 /* update the extent length and mark as initialized */
2839 ex->ee_len = cpu_to_le32(ee_len);
2840 ext4_ext_try_to_merge(inode, path, ex);
2841 err = ext4_ext_dirty(handle, inode, path + depth);
2844 goto fix_extent_len;
2847 ext4_ext_show_leaf(inode, path);
2851 ex->ee_len = orig_ex.ee_len;
2852 ext4_ext_dirty(handle, inode, path + depth);
2857 * ext4_split_extents() splits an extent and mark extent which is covered
2858 * by @map as split_flags indicates
2860 * It may result in splitting the extent into multiple extents (upto three)
2861 * There are three possibilities:
2862 * a> There is no split required
2863 * b> Splits in two extents: Split is happening at either end of the extent
2864 * c> Splits in three extents: Somone is splitting in middle of the extent
2867 static int ext4_split_extent(handle_t *handle,
2868 struct inode *inode,
2869 struct ext4_ext_path *path,
2870 struct ext4_map_blocks *map,
2874 ext4_lblk_t ee_block;
2875 struct ext4_extent *ex;
2876 unsigned int ee_len, depth;
2879 int split_flag1, flags1;
2881 depth = ext_depth(inode);
2882 ex = path[depth].p_ext;
2883 ee_block = le32_to_cpu(ex->ee_block);
2884 ee_len = ext4_ext_get_actual_len(ex);
2885 uninitialized = ext4_ext_is_uninitialized(ex);
2887 if (map->m_lblk + map->m_len < ee_block + ee_len) {
2888 split_flag1 = split_flag & EXT4_EXT_MAY_ZEROOUT ?
2889 EXT4_EXT_MAY_ZEROOUT : 0;
2890 flags1 = flags | EXT4_GET_BLOCKS_PRE_IO;
2892 split_flag1 |= EXT4_EXT_MARK_UNINIT1 |
2893 EXT4_EXT_MARK_UNINIT2;
2894 err = ext4_split_extent_at(handle, inode, path,
2895 map->m_lblk + map->m_len, split_flag1, flags1);
2900 ext4_ext_drop_refs(path);
2901 path = ext4_ext_find_extent(inode, map->m_lblk, path);
2903 return PTR_ERR(path);
2905 if (map->m_lblk >= ee_block) {
2906 split_flag1 = split_flag & EXT4_EXT_MAY_ZEROOUT ?
2907 EXT4_EXT_MAY_ZEROOUT : 0;
2909 split_flag1 |= EXT4_EXT_MARK_UNINIT1;
2910 if (split_flag & EXT4_EXT_MARK_UNINIT2)
2911 split_flag1 |= EXT4_EXT_MARK_UNINIT2;
2912 err = ext4_split_extent_at(handle, inode, path,
2913 map->m_lblk, split_flag1, flags);
2918 ext4_ext_show_leaf(inode, path);
2920 return err ? err : map->m_len;
2923 #define EXT4_EXT_ZERO_LEN 7
2925 * This function is called by ext4_ext_map_blocks() if someone tries to write
2926 * to an uninitialized extent. It may result in splitting the uninitialized
2927 * extent into multiple extents (up to three - one initialized and two
2929 * There are three possibilities:
2930 * a> There is no split required: Entire extent should be initialized
2931 * b> Splits in two extents: Write is happening at either end of the extent
2932 * c> Splits in three extents: Somone is writing in middle of the extent
2934 static int ext4_ext_convert_to_initialized(handle_t *handle,
2935 struct inode *inode,
2936 struct ext4_map_blocks *map,
2937 struct ext4_ext_path *path)
2939 struct ext4_map_blocks split_map;
2940 struct ext4_extent zero_ex;
2941 struct ext4_extent *ex;
2942 ext4_lblk_t ee_block, eof_block;
2943 unsigned int allocated, ee_len, depth;
2947 ext_debug("ext4_ext_convert_to_initialized: inode %lu, logical"
2948 "block %llu, max_blocks %u\n", inode->i_ino,
2949 (unsigned long long)map->m_lblk, map->m_len);
2951 eof_block = (inode->i_size + inode->i_sb->s_blocksize - 1) >>
2952 inode->i_sb->s_blocksize_bits;
2953 if (eof_block < map->m_lblk + map->m_len)
2954 eof_block = map->m_lblk + map->m_len;
2956 depth = ext_depth(inode);
2957 ex = path[depth].p_ext;
2958 ee_block = le32_to_cpu(ex->ee_block);
2959 ee_len = ext4_ext_get_actual_len(ex);
2960 allocated = ee_len - (map->m_lblk - ee_block);
2962 WARN_ON(map->m_lblk < ee_block);
2964 * It is safe to convert extent to initialized via explicit
2965 * zeroout only if extent is fully insde i_size or new_size.
2967 split_flag |= ee_block + ee_len <= eof_block ? EXT4_EXT_MAY_ZEROOUT : 0;
2969 /* If extent has less than 2*EXT4_EXT_ZERO_LEN zerout directly */
2970 if (ee_len <= 2*EXT4_EXT_ZERO_LEN &&
2971 (EXT4_EXT_MAY_ZEROOUT & split_flag)) {
2972 err = ext4_ext_zeroout(inode, ex);
2976 err = ext4_ext_get_access(handle, inode, path + depth);
2979 ext4_ext_mark_initialized(ex);
2980 ext4_ext_try_to_merge(inode, path, ex);
2981 err = ext4_ext_dirty(handle, inode, path + depth);
2987 * 1. split the extent into three extents.
2988 * 2. split the extent into two extents, zeroout the first half.
2989 * 3. split the extent into two extents, zeroout the second half.
2990 * 4. split the extent into two extents with out zeroout.
2992 split_map.m_lblk = map->m_lblk;
2993 split_map.m_len = map->m_len;
2995 if (allocated > map->m_len) {
2996 if (allocated <= EXT4_EXT_ZERO_LEN &&
2997 (EXT4_EXT_MAY_ZEROOUT & split_flag)) {
3000 cpu_to_le32(map->m_lblk);
3001 zero_ex.ee_len = cpu_to_le16(allocated);
3002 ext4_ext_store_pblock(&zero_ex,
3003 ext4_ext_pblock(ex) + map->m_lblk - ee_block);
3004 err = ext4_ext_zeroout(inode, &zero_ex);
3007 split_map.m_lblk = map->m_lblk;
3008 split_map.m_len = allocated;
3009 } else if ((map->m_lblk - ee_block + map->m_len <
3010 EXT4_EXT_ZERO_LEN) &&
3011 (EXT4_EXT_MAY_ZEROOUT & split_flag)) {
3013 if (map->m_lblk != ee_block) {
3014 zero_ex.ee_block = ex->ee_block;
3015 zero_ex.ee_len = cpu_to_le16(map->m_lblk -
3017 ext4_ext_store_pblock(&zero_ex,
3018 ext4_ext_pblock(ex));
3019 err = ext4_ext_zeroout(inode, &zero_ex);
3024 split_map.m_lblk = ee_block;
3025 split_map.m_len = map->m_lblk - ee_block + map->m_len;
3026 allocated = map->m_len;
3030 allocated = ext4_split_extent(handle, inode, path,
3031 &split_map, split_flag, 0);
3036 return err ? err : allocated;
3040 * This function is called by ext4_ext_map_blocks() from
3041 * ext4_get_blocks_dio_write() when DIO to write
3042 * to an uninitialized extent.
3044 * Writing to an uninitialized extent may result in splitting the uninitialized
3045 * extent into multiple /initialized uninitialized extents (up to three)
3046 * There are three possibilities:
3047 * a> There is no split required: Entire extent should be uninitialized
3048 * b> Splits in two extents: Write is happening at either end of the extent
3049 * c> Splits in three extents: Somone is writing in middle of the extent
3051 * One of more index blocks maybe needed if the extent tree grow after
3052 * the uninitialized extent split. To prevent ENOSPC occur at the IO
3053 * complete, we need to split the uninitialized extent before DIO submit
3054 * the IO. The uninitialized extent called at this time will be split
3055 * into three uninitialized extent(at most). After IO complete, the part
3056 * being filled will be convert to initialized by the end_io callback function
3057 * via ext4_convert_unwritten_extents().
3059 * Returns the size of uninitialized extent to be written on success.
3061 static int ext4_split_unwritten_extents(handle_t *handle,
3062 struct inode *inode,
3063 struct ext4_map_blocks *map,
3064 struct ext4_ext_path *path,
3067 ext4_lblk_t eof_block;
3068 ext4_lblk_t ee_block;
3069 struct ext4_extent *ex;
3070 unsigned int ee_len;
3071 int split_flag = 0, depth;
3073 ext_debug("ext4_split_unwritten_extents: inode %lu, logical"
3074 "block %llu, max_blocks %u\n", inode->i_ino,
3075 (unsigned long long)map->m_lblk, map->m_len);
3077 eof_block = (inode->i_size + inode->i_sb->s_blocksize - 1) >>
3078 inode->i_sb->s_blocksize_bits;
3079 if (eof_block < map->m_lblk + map->m_len)
3080 eof_block = map->m_lblk + map->m_len;
3082 * It is safe to convert extent to initialized via explicit
3083 * zeroout only if extent is fully insde i_size or new_size.
3085 depth = ext_depth(inode);
3086 ex = path[depth].p_ext;
3087 ee_block = le32_to_cpu(ex->ee_block);
3088 ee_len = ext4_ext_get_actual_len(ex);
3090 split_flag |= ee_block + ee_len <= eof_block ? EXT4_EXT_MAY_ZEROOUT : 0;
3091 split_flag |= EXT4_EXT_MARK_UNINIT2;
3093 flags |= EXT4_GET_BLOCKS_PRE_IO;
3094 return ext4_split_extent(handle, inode, path, map, split_flag, flags);
3097 static int ext4_convert_unwritten_extents_endio(handle_t *handle,
3098 struct inode *inode,
3099 struct ext4_ext_path *path)
3101 struct ext4_extent *ex;
3102 struct ext4_extent_header *eh;
3106 depth = ext_depth(inode);
3107 eh = path[depth].p_hdr;
3108 ex = path[depth].p_ext;
3110 ext_debug("ext4_convert_unwritten_extents_endio: inode %lu, logical"
3111 "block %llu, max_blocks %u\n", inode->i_ino,
3112 (unsigned long long)le32_to_cpu(ex->ee_block),
3113 ext4_ext_get_actual_len(ex));
3115 err = ext4_ext_get_access(handle, inode, path + depth);
3118 /* first mark the extent as initialized */
3119 ext4_ext_mark_initialized(ex);
3121 /* note: ext4_ext_correct_indexes() isn't needed here because
3122 * borders are not changed
3124 ext4_ext_try_to_merge(inode, path, ex);
3126 /* Mark modified extent as dirty */
3127 err = ext4_ext_dirty(handle, inode, path + depth);
3129 ext4_ext_show_leaf(inode, path);
3133 static void unmap_underlying_metadata_blocks(struct block_device *bdev,
3134 sector_t block, int count)
3137 for (i = 0; i < count; i++)
3138 unmap_underlying_metadata(bdev, block + i);
3142 * Handle EOFBLOCKS_FL flag, clearing it if necessary
3144 static int check_eofblocks_fl(handle_t *handle, struct inode *inode,
3146 struct ext4_ext_path *path,
3150 struct ext4_extent_header *eh;
3151 struct ext4_extent *last_ex;
3153 if (!ext4_test_inode_flag(inode, EXT4_INODE_EOFBLOCKS))
3156 depth = ext_depth(inode);
3157 eh = path[depth].p_hdr;
3159 if (unlikely(!eh->eh_entries)) {
3160 EXT4_ERROR_INODE(inode, "eh->eh_entries == 0 and "
3161 "EOFBLOCKS_FL set");
3164 last_ex = EXT_LAST_EXTENT(eh);
3166 * We should clear the EOFBLOCKS_FL flag if we are writing the
3167 * last block in the last extent in the file. We test this by
3168 * first checking to see if the caller to
3169 * ext4_ext_get_blocks() was interested in the last block (or
3170 * a block beyond the last block) in the current extent. If
3171 * this turns out to be false, we can bail out from this
3172 * function immediately.
3174 if (lblk + len < le32_to_cpu(last_ex->ee_block) +
3175 ext4_ext_get_actual_len(last_ex))
3178 * If the caller does appear to be planning to write at or
3179 * beyond the end of the current extent, we then test to see
3180 * if the current extent is the last extent in the file, by
3181 * checking to make sure it was reached via the rightmost node
3182 * at each level of the tree.
3184 for (i = depth-1; i >= 0; i--)
3185 if (path[i].p_idx != EXT_LAST_INDEX(path[i].p_hdr))
3187 ext4_clear_inode_flag(inode, EXT4_INODE_EOFBLOCKS);
3188 return ext4_mark_inode_dirty(handle, inode);
3192 ext4_ext_handle_uninitialized_extents(handle_t *handle, struct inode *inode,
3193 struct ext4_map_blocks *map,
3194 struct ext4_ext_path *path, int flags,
3195 unsigned int allocated, ext4_fsblk_t newblock)
3199 ext4_io_end_t *io = EXT4_I(inode)->cur_aio_dio;
3201 ext_debug("ext4_ext_handle_uninitialized_extents: inode %lu, logical"
3202 "block %llu, max_blocks %u, flags %d, allocated %u",
3203 inode->i_ino, (unsigned long long)map->m_lblk, map->m_len,
3205 ext4_ext_show_leaf(inode, path);
3207 /* get_block() before submit the IO, split the extent */
3208 if ((flags & EXT4_GET_BLOCKS_PRE_IO)) {
3209 ret = ext4_split_unwritten_extents(handle, inode, map,
3212 * Flag the inode(non aio case) or end_io struct (aio case)
3213 * that this IO needs to conversion to written when IO is
3216 if (io && !(io->flag & EXT4_IO_END_UNWRITTEN)) {
3217 io->flag = EXT4_IO_END_UNWRITTEN;
3218 atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten);
3220 ext4_set_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN);
3221 if (ext4_should_dioread_nolock(inode))
3222 map->m_flags |= EXT4_MAP_UNINIT;
3225 /* IO end_io complete, convert the filled extent to written */
3226 if ((flags & EXT4_GET_BLOCKS_CONVERT)) {
3227 ret = ext4_convert_unwritten_extents_endio(handle, inode,
3230 ext4_update_inode_fsync_trans(handle, inode, 1);
3231 err = check_eofblocks_fl(handle, inode, map->m_lblk,
3237 /* buffered IO case */
3239 * repeat fallocate creation request
3240 * we already have an unwritten extent
3242 if (flags & EXT4_GET_BLOCKS_UNINIT_EXT)
3245 /* buffered READ or buffered write_begin() lookup */
3246 if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
3248 * We have blocks reserved already. We
3249 * return allocated blocks so that delalloc
3250 * won't do block reservation for us. But
3251 * the buffer head will be unmapped so that
3252 * a read from the block returns 0s.
3254 map->m_flags |= EXT4_MAP_UNWRITTEN;
3258 /* buffered write, writepage time, convert*/
3259 ret = ext4_ext_convert_to_initialized(handle, inode, map, path);
3261 ext4_update_inode_fsync_trans(handle, inode, 1);
3262 err = check_eofblocks_fl(handle, inode, map->m_lblk, path,
3274 map->m_flags |= EXT4_MAP_NEW;
3276 * if we allocated more blocks than requested
3277 * we need to make sure we unmap the extra block
3278 * allocated. The actual needed block will get
3279 * unmapped later when we find the buffer_head marked
3282 if (allocated > map->m_len) {
3283 unmap_underlying_metadata_blocks(inode->i_sb->s_bdev,
3284 newblock + map->m_len,
3285 allocated - map->m_len);
3286 allocated = map->m_len;
3290 * If we have done fallocate with the offset that is already
3291 * delayed allocated, we would have block reservation
3292 * and quota reservation done in the delayed write path.
3293 * But fallocate would have already updated quota and block
3294 * count for this offset. So cancel these reservation
3296 if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE)
3297 ext4_da_update_reserve_space(inode, allocated, 0);
3300 map->m_flags |= EXT4_MAP_MAPPED;
3302 if (allocated > map->m_len)
3303 allocated = map->m_len;
3304 ext4_ext_show_leaf(inode, path);
3305 map->m_pblk = newblock;
3306 map->m_len = allocated;
3309 ext4_ext_drop_refs(path);
3312 return err ? err : allocated;
3316 * Block allocation/map/preallocation routine for extents based files
3319 * Need to be called with
3320 * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system block
3321 * (ie, create is zero). Otherwise down_write(&EXT4_I(inode)->i_data_sem)
3323 * return > 0, number of of blocks already mapped/allocated
3324 * if create == 0 and these are pre-allocated blocks
3325 * buffer head is unmapped
3326 * otherwise blocks are mapped
3328 * return = 0, if plain look up failed (blocks have not been allocated)
3329 * buffer head is unmapped
3331 * return < 0, error case.
3333 int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
3334 struct ext4_map_blocks *map, int flags)
3336 struct ext4_ext_path *path = NULL;
3337 struct ext4_extent newex, *ex;
3338 ext4_fsblk_t newblock = 0;
3339 int err = 0, depth, ret;
3340 unsigned int allocated = 0;
3341 unsigned int punched_out = 0;
3342 unsigned int result = 0;
3343 struct ext4_allocation_request ar;
3344 ext4_io_end_t *io = EXT4_I(inode)->cur_aio_dio;
3345 struct ext4_map_blocks punch_map;
3347 ext_debug("blocks %u/%u requested for inode %lu\n",
3348 map->m_lblk, map->m_len, inode->i_ino);
3349 trace_ext4_ext_map_blocks_enter(inode, map->m_lblk, map->m_len, flags);
3351 /* check in cache */
3352 if (ext4_ext_in_cache(inode, map->m_lblk, &newex) &&
3353 ((flags & EXT4_GET_BLOCKS_PUNCH_OUT_EXT) == 0)) {
3354 if (!newex.ee_start_lo && !newex.ee_start_hi) {
3355 if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
3357 * block isn't allocated yet and
3358 * user doesn't want to allocate it
3362 /* we should allocate requested block */
3364 /* block is already allocated */
3365 newblock = map->m_lblk
3366 - le32_to_cpu(newex.ee_block)
3367 + ext4_ext_pblock(&newex);
3368 /* number of remaining blocks in the extent */
3369 allocated = ext4_ext_get_actual_len(&newex) -
3370 (map->m_lblk - le32_to_cpu(newex.ee_block));
3375 /* find extent for this block */
3376 path = ext4_ext_find_extent(inode, map->m_lblk, NULL);
3378 err = PTR_ERR(path);
3383 depth = ext_depth(inode);
3386 * consistent leaf must not be empty;
3387 * this situation is possible, though, _during_ tree modification;
3388 * this is why assert can't be put in ext4_ext_find_extent()
3390 if (unlikely(path[depth].p_ext == NULL && depth != 0)) {
3391 EXT4_ERROR_INODE(inode, "bad extent address "
3392 "lblock: %lu, depth: %d pblock %lld",
3393 (unsigned long) map->m_lblk, depth,
3394 path[depth].p_block);
3399 ex = path[depth].p_ext;
3401 ext4_lblk_t ee_block = le32_to_cpu(ex->ee_block);
3402 ext4_fsblk_t ee_start = ext4_ext_pblock(ex);
3403 unsigned short ee_len;
3406 * Uninitialized extents are treated as holes, except that
3407 * we split out initialized portions during a write.
3409 ee_len = ext4_ext_get_actual_len(ex);
3410 /* if found extent covers block, simply return it */
3411 if (in_range(map->m_lblk, ee_block, ee_len)) {
3412 newblock = map->m_lblk - ee_block + ee_start;
3413 /* number of remaining blocks in the extent */
3414 allocated = ee_len - (map->m_lblk - ee_block);
3415 ext_debug("%u fit into %u:%d -> %llu\n", map->m_lblk,
3416 ee_block, ee_len, newblock);
3418 if ((flags & EXT4_GET_BLOCKS_PUNCH_OUT_EXT) == 0) {
3420 * Do not put uninitialized extent
3423 if (!ext4_ext_is_uninitialized(ex)) {
3424 ext4_ext_put_in_cache(inode, ee_block,
3428 ret = ext4_ext_handle_uninitialized_extents(
3429 handle, inode, map, path, flags,
3430 allocated, newblock);
3435 * Punch out the map length, but only to the
3438 punched_out = allocated < map->m_len ?
3439 allocated : map->m_len;
3442 * Sense extents need to be converted to
3443 * uninitialized, they must fit in an
3444 * uninitialized extent
3446 if (punched_out > EXT_UNINIT_MAX_LEN)
3447 punched_out = EXT_UNINIT_MAX_LEN;
3449 punch_map.m_lblk = map->m_lblk;
3450 punch_map.m_pblk = newblock;
3451 punch_map.m_len = punched_out;
3452 punch_map.m_flags = 0;
3454 /* Check to see if the extent needs to be split */
3455 if (punch_map.m_len != ee_len ||
3456 punch_map.m_lblk != ee_block) {
3458 ret = ext4_split_extent(handle, inode,
3459 path, &punch_map, 0,
3460 EXT4_GET_BLOCKS_PUNCH_OUT_EXT |
3461 EXT4_GET_BLOCKS_PRE_IO);
3468 * find extent for the block at
3469 * the start of the hole
3471 ext4_ext_drop_refs(path);
3474 path = ext4_ext_find_extent(inode,
3477 err = PTR_ERR(path);
3482 depth = ext_depth(inode);
3483 ex = path[depth].p_ext;
3484 ee_len = ext4_ext_get_actual_len(ex);
3485 ee_block = le32_to_cpu(ex->ee_block);
3486 ee_start = ext4_ext_pblock(ex);
3490 ext4_ext_mark_uninitialized(ex);
3492 err = ext4_ext_remove_space(inode, map->m_lblk,
3493 map->m_lblk + punched_out);
3500 * requested block isn't allocated yet;
3501 * we couldn't try to create block if create flag is zero
3503 if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
3505 * put just found gap into cache to speed up
3506 * subsequent requests
3508 ext4_ext_put_gap_in_cache(inode, path, map->m_lblk);
3512 * Okay, we need to do block allocation.
3515 /* find neighbour allocated blocks */
3516 ar.lleft = map->m_lblk;
3517 err = ext4_ext_search_left(inode, path, &ar.lleft, &ar.pleft);
3520 ar.lright = map->m_lblk;
3521 err = ext4_ext_search_right(inode, path, &ar.lright, &ar.pright);
3526 * See if request is beyond maximum number of blocks we can have in
3527 * a single extent. For an initialized extent this limit is
3528 * EXT_INIT_MAX_LEN and for an uninitialized extent this limit is
3529 * EXT_UNINIT_MAX_LEN.
3531 if (map->m_len > EXT_INIT_MAX_LEN &&
3532 !(flags & EXT4_GET_BLOCKS_UNINIT_EXT))
3533 map->m_len = EXT_INIT_MAX_LEN;
3534 else if (map->m_len > EXT_UNINIT_MAX_LEN &&
3535 (flags & EXT4_GET_BLOCKS_UNINIT_EXT))
3536 map->m_len = EXT_UNINIT_MAX_LEN;
3538 /* Check if we can really insert (m_lblk)::(m_lblk + m_len) extent */
3539 newex.ee_block = cpu_to_le32(map->m_lblk);
3540 newex.ee_len = cpu_to_le16(map->m_len);
3541 err = ext4_ext_check_overlap(inode, &newex, path);
3543 allocated = ext4_ext_get_actual_len(&newex);
3545 allocated = map->m_len;
3547 /* allocate new block */
3549 ar.goal = ext4_ext_find_goal(inode, path, map->m_lblk);
3550 ar.logical = map->m_lblk;
3552 if (S_ISREG(inode->i_mode))
3553 ar.flags = EXT4_MB_HINT_DATA;
3555 /* disable in-core preallocation for non-regular files */
3557 if (flags & EXT4_GET_BLOCKS_NO_NORMALIZE)
3558 ar.flags |= EXT4_MB_HINT_NOPREALLOC;
3559 newblock = ext4_mb_new_blocks(handle, &ar, &err);
3562 ext_debug("allocate new block: goal %llu, found %llu/%u\n",
3563 ar.goal, newblock, allocated);
3565 /* try to insert new extent into found leaf and return */
3566 ext4_ext_store_pblock(&newex, newblock);
3567 newex.ee_len = cpu_to_le16(ar.len);
3568 /* Mark uninitialized */
3569 if (flags & EXT4_GET_BLOCKS_UNINIT_EXT){
3570 ext4_ext_mark_uninitialized(&newex);
3572 * io_end structure was created for every IO write to an
3573 * uninitialized extent. To avoid unnecessary conversion,
3574 * here we flag the IO that really needs the conversion.
3575 * For non asycn direct IO case, flag the inode state
3576 * that we need to perform conversion when IO is done.
3578 if ((flags & EXT4_GET_BLOCKS_PRE_IO)) {
3579 if (io && !(io->flag & EXT4_IO_END_UNWRITTEN)) {
3580 io->flag = EXT4_IO_END_UNWRITTEN;
3581 atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten);
3583 ext4_set_inode_state(inode,
3584 EXT4_STATE_DIO_UNWRITTEN);
3586 if (ext4_should_dioread_nolock(inode))
3587 map->m_flags |= EXT4_MAP_UNINIT;
3590 err = check_eofblocks_fl(handle, inode, map->m_lblk, path, ar.len);
3594 err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
3596 /* free data blocks we just allocated */
3597 /* not a good idea to call discard here directly,
3598 * but otherwise we'd need to call it every free() */
3599 ext4_discard_preallocations(inode);
3600 ext4_free_blocks(handle, inode, NULL, ext4_ext_pblock(&newex),
3601 ext4_ext_get_actual_len(&newex), 0);
3605 /* previous routine could use block we allocated */
3606 newblock = ext4_ext_pblock(&newex);
3607 allocated = ext4_ext_get_actual_len(&newex);
3608 if (allocated > map->m_len)
3609 allocated = map->m_len;
3610 map->m_flags |= EXT4_MAP_NEW;
3613 * Update reserved blocks/metadata blocks after successful
3614 * block allocation which had been deferred till now.
3616 if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE)
3617 ext4_da_update_reserve_space(inode, allocated, 1);
3620 * Cache the extent and update transaction to commit on fdatasync only
3621 * when it is _not_ an uninitialized extent.
3623 if ((flags & EXT4_GET_BLOCKS_UNINIT_EXT) == 0) {
3624 ext4_ext_put_in_cache(inode, map->m_lblk, allocated, newblock);
3625 ext4_update_inode_fsync_trans(handle, inode, 1);
3627 ext4_update_inode_fsync_trans(handle, inode, 0);
3629 if (allocated > map->m_len)
3630 allocated = map->m_len;
3631 ext4_ext_show_leaf(inode, path);
3632 map->m_flags |= EXT4_MAP_MAPPED;
3633 map->m_pblk = newblock;
3634 map->m_len = allocated;
3637 ext4_ext_drop_refs(path);
3640 trace_ext4_ext_map_blocks_exit(inode, map->m_lblk,
3641 newblock, map->m_len, err ? err : allocated);
3643 result = (flags & EXT4_GET_BLOCKS_PUNCH_OUT_EXT) ?
3644 punched_out : allocated;
3646 return err ? err : result;
3649 void ext4_ext_truncate(struct inode *inode)
3651 struct address_space *mapping = inode->i_mapping;
3652 struct super_block *sb = inode->i_sb;
3653 ext4_lblk_t last_block;
3658 * finish any pending end_io work so we won't run the risk of
3659 * converting any truncated blocks to initialized later
3661 ext4_flush_completed_IO(inode);
3664 * probably first extent we're gonna free will be last in block
3666 err = ext4_writepage_trans_blocks(inode);
3667 handle = ext4_journal_start(inode, err);
3671 if (inode->i_size & (sb->s_blocksize - 1))
3672 ext4_block_truncate_page(handle, mapping, inode->i_size);
3674 if (ext4_orphan_add(handle, inode))
3677 down_write(&EXT4_I(inode)->i_data_sem);
3678 ext4_ext_invalidate_cache(inode);
3680 ext4_discard_preallocations(inode);
3683 * TODO: optimization is possible here.
3684 * Probably we need not scan at all,
3685 * because page truncation is enough.
3688 /* we have to know where to truncate from in crash case */
3689 EXT4_I(inode)->i_disksize = inode->i_size;
3690 ext4_mark_inode_dirty(handle, inode);
3692 last_block = (inode->i_size + sb->s_blocksize - 1)
3693 >> EXT4_BLOCK_SIZE_BITS(sb);
3694 err = ext4_ext_remove_space(inode, last_block, EXT_MAX_BLOCK);
3696 /* In a multi-transaction truncate, we only make the final
3697 * transaction synchronous.
3700 ext4_handle_sync(handle);
3702 up_write(&EXT4_I(inode)->i_data_sem);
3706 * If this was a simple ftruncate() and the file will remain alive,
3707 * then we need to clear up the orphan record which we created above.
3708 * However, if this was a real unlink then we were called by
3709 * ext4_delete_inode(), and we allow that function to clean up the
3710 * orphan info for us.
3713 ext4_orphan_del(handle, inode);
3715 inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
3716 ext4_mark_inode_dirty(handle, inode);
3717 ext4_journal_stop(handle);
3720 static void ext4_falloc_update_inode(struct inode *inode,
3721 int mode, loff_t new_size, int update_ctime)
3723 struct timespec now;
3726 now = current_fs_time(inode->i_sb);
3727 if (!timespec_equal(&inode->i_ctime, &now))
3728 inode->i_ctime = now;
3731 * Update only when preallocation was requested beyond
3734 if (!(mode & FALLOC_FL_KEEP_SIZE)) {
3735 if (new_size > i_size_read(inode))
3736 i_size_write(inode, new_size);
3737 if (new_size > EXT4_I(inode)->i_disksize)
3738 ext4_update_i_disksize(inode, new_size);
3741 * Mark that we allocate beyond EOF so the subsequent truncate
3742 * can proceed even if the new size is the same as i_size.
3744 if (new_size > i_size_read(inode))
3745 ext4_set_inode_flag(inode, EXT4_INODE_EOFBLOCKS);
3751 * preallocate space for a file. This implements ext4's fallocate file
3752 * operation, which gets called from sys_fallocate system call.
3753 * For block-mapped files, posix_fallocate should fall back to the method
3754 * of writing zeroes to the required new blocks (the same behavior which is
3755 * expected for file systems which do not support fallocate() system call).
3757 long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
3759 struct inode *inode = file->f_path.dentry->d_inode;
3762 unsigned int max_blocks;
3766 struct ext4_map_blocks map;
3767 unsigned int credits, blkbits = inode->i_blkbits;
3770 * currently supporting (pre)allocate mode for extent-based
3773 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
3776 /* Return error if mode is not supported */
3777 if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
3780 if (mode & FALLOC_FL_PUNCH_HOLE)
3781 return ext4_punch_hole(file, offset, len);
3783 trace_ext4_fallocate_enter(inode, offset, len, mode);
3784 map.m_lblk = offset >> blkbits;
3786 * We can't just convert len to max_blocks because
3787 * If blocksize = 4096 offset = 3072 and len = 2048
3789 max_blocks = (EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits)
3792 * credits to insert 1 extent into extent tree
3794 credits = ext4_chunk_trans_blocks(inode, max_blocks);
3795 mutex_lock(&inode->i_mutex);
3796 ret = inode_newsize_ok(inode, (len + offset));
3798 mutex_unlock(&inode->i_mutex);
3799 trace_ext4_fallocate_exit(inode, offset, max_blocks, ret);
3803 while (ret >= 0 && ret < max_blocks) {
3804 map.m_lblk = map.m_lblk + ret;
3805 map.m_len = max_blocks = max_blocks - ret;
3806 handle = ext4_journal_start(inode, credits);
3807 if (IS_ERR(handle)) {
3808 ret = PTR_ERR(handle);
3811 ret = ext4_map_blocks(handle, inode, &map,
3812 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT |
3813 EXT4_GET_BLOCKS_NO_NORMALIZE);
3817 printk(KERN_ERR "%s: ext4_ext_map_blocks "
3818 "returned error inode#%lu, block=%u, "
3819 "max_blocks=%u", __func__,
3820 inode->i_ino, map.m_lblk, max_blocks);
3822 ext4_mark_inode_dirty(handle, inode);
3823 ret2 = ext4_journal_stop(handle);
3826 if ((map.m_lblk + ret) >= (EXT4_BLOCK_ALIGN(offset + len,
3827 blkbits) >> blkbits))
3828 new_size = offset + len;
3830 new_size = (map.m_lblk + ret) << blkbits;
3832 ext4_falloc_update_inode(inode, mode, new_size,
3833 (map.m_flags & EXT4_MAP_NEW));
3834 ext4_mark_inode_dirty(handle, inode);
3835 ret2 = ext4_journal_stop(handle);
3839 if (ret == -ENOSPC &&
3840 ext4_should_retry_alloc(inode->i_sb, &retries)) {
3844 mutex_unlock(&inode->i_mutex);
3845 trace_ext4_fallocate_exit(inode, offset, max_blocks,
3846 ret > 0 ? ret2 : ret);
3847 return ret > 0 ? ret2 : ret;
3851 * This function convert a range of blocks to written extents
3852 * The caller of this function will pass the start offset and the size.
3853 * all unwritten extents within this range will be converted to
3856 * This function is called from the direct IO end io call back
3857 * function, to convert the fallocated extents after IO is completed.
3858 * Returns 0 on success.
3860 int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
3864 unsigned int max_blocks;
3867 struct ext4_map_blocks map;
3868 unsigned int credits, blkbits = inode->i_blkbits;
3870 map.m_lblk = offset >> blkbits;
3872 * We can't just convert len to max_blocks because
3873 * If blocksize = 4096 offset = 3072 and len = 2048
3875 max_blocks = ((EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits) -
3878 * credits to insert 1 extent into extent tree
3880 credits = ext4_chunk_trans_blocks(inode, max_blocks);
3881 while (ret >= 0 && ret < max_blocks) {
3883 map.m_len = (max_blocks -= ret);
3884 handle = ext4_journal_start(inode, credits);
3885 if (IS_ERR(handle)) {
3886 ret = PTR_ERR(handle);
3889 ret = ext4_map_blocks(handle, inode, &map,
3890 EXT4_GET_BLOCKS_IO_CONVERT_EXT);
3893 printk(KERN_ERR "%s: ext4_ext_map_blocks "
3894 "returned error inode#%lu, block=%u, "
3895 "max_blocks=%u", __func__,
3896 inode->i_ino, map.m_lblk, map.m_len);
3898 ext4_mark_inode_dirty(handle, inode);
3899 ret2 = ext4_journal_stop(handle);
3900 if (ret <= 0 || ret2 )
3903 return ret > 0 ? ret2 : ret;
3907 * Callback function called for each extent to gather FIEMAP information.
3909 static int ext4_ext_fiemap_cb(struct inode *inode, struct ext4_ext_path *path,
3910 struct ext4_ext_cache *newex, struct ext4_extent *ex,
3919 struct fiemap_extent_info *fieinfo = data;
3920 unsigned char blksize_bits;
3922 blksize_bits = inode->i_sb->s_blocksize_bits;
3923 logical = (__u64)newex->ec_block << blksize_bits;
3925 if (newex->ec_start == 0) {
3927 * No extent in extent-tree contains block @newex->ec_start,
3928 * then the block may stay in 1)a hole or 2)delayed-extent.
3930 * Holes or delayed-extents are processed as follows.
3931 * 1. lookup dirty pages with specified range in pagecache.
3932 * If no page is got, then there is no delayed-extent and
3933 * return with EXT_CONTINUE.
3934 * 2. find the 1st mapped buffer,
3935 * 3. check if the mapped buffer is both in the request range
3936 * and a delayed buffer. If not, there is no delayed-extent,
3938 * 4. a delayed-extent is found, the extent will be collected.
3940 ext4_lblk_t end = 0;
3941 pgoff_t last_offset;
3944 pgoff_t start_index = 0;
3945 struct page **pages = NULL;
3946 struct buffer_head *bh = NULL;
3947 struct buffer_head *head = NULL;
3948 unsigned int nr_pages = PAGE_SIZE / sizeof(struct page *);
3950 pages = kmalloc(PAGE_SIZE, GFP_KERNEL);
3954 offset = logical >> PAGE_SHIFT;
3956 last_offset = offset;
3958 ret = find_get_pages_tag(inode->i_mapping, &offset,
3959 PAGECACHE_TAG_DIRTY, nr_pages, pages);
3961 if (!(flags & FIEMAP_EXTENT_DELALLOC)) {
3962 /* First time, try to find a mapped buffer. */
3965 for (index = 0; index < ret; index++)
3966 page_cache_release(pages[index]);
3969 return EXT_CONTINUE;
3974 /* Try to find the 1st mapped buffer. */
3975 end = ((__u64)pages[index]->index << PAGE_SHIFT) >>
3977 if (!page_has_buffers(pages[index]))
3979 head = page_buffers(pages[index]);
3986 if (end >= newex->ec_block +
3988 /* The buffer is out of
3989 * the request range.
3993 if (buffer_mapped(bh) &&
3994 end >= newex->ec_block) {
3995 start_index = index - 1;
3996 /* get the 1st mapped buffer. */
3997 goto found_mapped_buffer;
4000 bh = bh->b_this_page;
4002 } while (bh != head);
4004 /* No mapped buffer in the range found in this page,
4005 * We need to look up next page.
4008 /* There is no page left, but we need to limit
4011 newex->ec_len = end - newex->ec_block;
4016 /*Find contiguous delayed buffers. */
4017 if (ret > 0 && pages[0]->index == last_offset)
4018 head = page_buffers(pages[0]);
4024 found_mapped_buffer:
4025 if (bh != NULL && buffer_delay(bh)) {
4026 /* 1st or contiguous delayed buffer found. */
4027 if (!(flags & FIEMAP_EXTENT_DELALLOC)) {
4029 * 1st delayed buffer found, record
4030 * the start of extent.
4032 flags |= FIEMAP_EXTENT_DELALLOC;
4033 newex->ec_block = end;
4034 logical = (__u64)end << blksize_bits;
4036 /* Find contiguous delayed buffers. */
4038 if (!buffer_delay(bh))
4039 goto found_delayed_extent;
4040 bh = bh->b_this_page;
4042 } while (bh != head);
4044 for (; index < ret; index++) {
4045 if (!page_has_buffers(pages[index])) {
4049 head = page_buffers(pages[index]);
4055 if (pages[index]->index !=
4056 pages[start_index]->index + index
4058 /* Blocks are not contiguous. */
4064 if (!buffer_delay(bh))
4065 /* Delayed-extent ends. */
4066 goto found_delayed_extent;
4067 bh = bh->b_this_page;
4069 } while (bh != head);
4071 } else if (!(flags & FIEMAP_EXTENT_DELALLOC))
4075 found_delayed_extent:
4076 newex->ec_len = min(end - newex->ec_block,
4077 (ext4_lblk_t)EXT_INIT_MAX_LEN);
4078 if (ret == nr_pages && bh != NULL &&
4079 newex->ec_len < EXT_INIT_MAX_LEN &&
4081 /* Have not collected an extent and continue. */
4082 for (index = 0; index < ret; index++)
4083 page_cache_release(pages[index]);
4087 for (index = 0; index < ret; index++)
4088 page_cache_release(pages[index]);
4092 physical = (__u64)newex->ec_start << blksize_bits;
4093 length = (__u64)newex->ec_len << blksize_bits;
4095 if (ex && ext4_ext_is_uninitialized(ex))
4096 flags |= FIEMAP_EXTENT_UNWRITTEN;
4098 size = i_size_read(inode);
4099 if (logical + length >= size)
4100 flags |= FIEMAP_EXTENT_LAST;
4102 ret = fiemap_fill_next_extent(fieinfo, logical, physical,
4108 return EXT_CONTINUE;
4111 /* fiemap flags we can handle specified here */
4112 #define EXT4_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC|FIEMAP_FLAG_XATTR)
4114 static int ext4_xattr_fiemap(struct inode *inode,
4115 struct fiemap_extent_info *fieinfo)
4119 __u32 flags = FIEMAP_EXTENT_LAST;
4120 int blockbits = inode->i_sb->s_blocksize_bits;
4124 if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) {
4125 struct ext4_iloc iloc;
4126 int offset; /* offset of xattr in inode */
4128 error = ext4_get_inode_loc(inode, &iloc);
4131 physical = iloc.bh->b_blocknr << blockbits;
4132 offset = EXT4_GOOD_OLD_INODE_SIZE +
4133 EXT4_I(inode)->i_extra_isize;
4135 length = EXT4_SB(inode->i_sb)->s_inode_size - offset;
4136 flags |= FIEMAP_EXTENT_DATA_INLINE;
4138 } else { /* external block */
4139 physical = EXT4_I(inode)->i_file_acl << blockbits;
4140 length = inode->i_sb->s_blocksize;
4144 error = fiemap_fill_next_extent(fieinfo, 0, physical,
4146 return (error < 0 ? error : 0);
4150 * ext4_ext_punch_hole
4152 * Punches a hole of "length" bytes in a file starting
4155 * @inode: The inode of the file to punch a hole in
4156 * @offset: The starting byte offset of the hole
4157 * @length: The length of the hole
4159 * Returns the number of blocks removed or negative on err
4161 int ext4_ext_punch_hole(struct file *file, loff_t offset, loff_t length)
4163 struct inode *inode = file->f_path.dentry->d_inode;
4164 struct super_block *sb = inode->i_sb;
4165 struct ext4_ext_cache cache_ex;
4166 ext4_lblk_t first_block, last_block, num_blocks, iblock, max_blocks;
4167 struct address_space *mapping = inode->i_mapping;
4168 struct ext4_map_blocks map;
4170 loff_t first_block_offset, last_block_offset, block_len;
4171 loff_t first_page, last_page, first_page_offset, last_page_offset;
4172 int ret, credits, blocks_released, err = 0;
4174 first_block = (offset + sb->s_blocksize - 1) >>
4175 EXT4_BLOCK_SIZE_BITS(sb);
4176 last_block = (offset + length) >> EXT4_BLOCK_SIZE_BITS(sb);
4178 first_block_offset = first_block << EXT4_BLOCK_SIZE_BITS(sb);
4179 last_block_offset = last_block << EXT4_BLOCK_SIZE_BITS(sb);
4181 first_page = (offset + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
4182 last_page = (offset + length) >> PAGE_CACHE_SHIFT;
4184 first_page_offset = first_page << PAGE_CACHE_SHIFT;
4185 last_page_offset = last_page << PAGE_CACHE_SHIFT;
4188 * Write out all dirty pages to avoid race conditions
4189 * Then release them.
4191 if (mapping->nrpages && mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) {
4192 err = filemap_write_and_wait_range(mapping,
4193 first_page_offset == 0 ? 0 : first_page_offset-1,
4200 /* Now release the pages */
4201 if (last_page_offset > first_page_offset) {
4202 truncate_inode_pages_range(mapping, first_page_offset,
4203 last_page_offset-1);
4206 /* finish any pending end_io work */
4207 ext4_flush_completed_IO(inode);
4209 credits = ext4_writepage_trans_blocks(inode);
4210 handle = ext4_journal_start(inode, credits);
4212 return PTR_ERR(handle);
4214 err = ext4_orphan_add(handle, inode);
4219 * Now we need to zero out the un block aligned data.
4220 * If the file is smaller than a block, just
4221 * zero out the middle
4223 if (first_block > last_block)
4224 ext4_block_zero_page_range(handle, mapping, offset, length);
4226 /* zero out the head of the hole before the first block */
4227 block_len = first_block_offset - offset;
4229 ext4_block_zero_page_range(handle, mapping,
4232 /* zero out the tail of the hole after the last block */
4233 block_len = offset + length - last_block_offset;
4234 if (block_len > 0) {
4235 ext4_block_zero_page_range(handle, mapping,
4236 last_block_offset, block_len);
4240 /* If there are no blocks to remove, return now */
4241 if (first_block >= last_block)
4244 down_write(&EXT4_I(inode)->i_data_sem);
4245 ext4_ext_invalidate_cache(inode);
4246 ext4_discard_preallocations(inode);
4249 * Loop over all the blocks and identify blocks
4250 * that need to be punched out
4252 iblock = first_block;
4253 blocks_released = 0;
4254 while (iblock < last_block) {
4255 max_blocks = last_block - iblock;
4257 memset(&map, 0, sizeof(map));
4258 map.m_lblk = iblock;
4259 map.m_len = max_blocks;
4260 ret = ext4_ext_map_blocks(handle, inode, &map,
4261 EXT4_GET_BLOCKS_PUNCH_OUT_EXT);
4264 blocks_released += ret;
4266 } else if (ret == 0) {
4268 * If map blocks could not find the block,
4269 * then it is in a hole. If the hole was
4270 * not already cached, then map blocks should
4271 * put it in the cache. So we can get the hole
4274 memset(&cache_ex, 0, sizeof(cache_ex));
4275 if ((ext4_ext_check_cache(inode, iblock, &cache_ex)) &&
4276 !cache_ex.ec_start) {
4278 /* The hole is cached */
4279 num_blocks = cache_ex.ec_block +
4280 cache_ex.ec_len - iblock;
4283 /* The block could not be identified */
4288 /* Map blocks error */
4293 if (num_blocks == 0) {
4294 /* This condition should never happen */
4295 ext_debug("Block lookup failed");
4300 iblock += num_blocks;
4303 if (blocks_released > 0) {
4304 ext4_ext_invalidate_cache(inode);
4305 ext4_discard_preallocations(inode);
4309 ext4_handle_sync(handle);
4311 up_write(&EXT4_I(inode)->i_data_sem);
4314 ext4_orphan_del(handle, inode);
4315 inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
4316 ext4_mark_inode_dirty(handle, inode);
4317 ext4_journal_stop(handle);
4320 int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
4321 __u64 start, __u64 len)
4323 ext4_lblk_t start_blk;
4326 /* fallback to generic here if not in extents fmt */
4327 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
4328 return generic_block_fiemap(inode, fieinfo, start, len,
4331 if (fiemap_check_flags(fieinfo, EXT4_FIEMAP_FLAGS))
4334 if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR) {
4335 error = ext4_xattr_fiemap(inode, fieinfo);
4337 ext4_lblk_t len_blks;
4340 start_blk = start >> inode->i_sb->s_blocksize_bits;
4341 last_blk = (start + len - 1) >> inode->i_sb->s_blocksize_bits;
4342 if (last_blk >= EXT_MAX_BLOCK)
4343 last_blk = EXT_MAX_BLOCK-1;
4344 len_blks = ((ext4_lblk_t) last_blk) - start_blk + 1;
4347 * Walk the extent tree gathering extent information.
4348 * ext4_ext_fiemap_cb will push extents back to user.
4350 error = ext4_ext_walk_space(inode, start_blk, len_blks,
4351 ext4_ext_fiemap_cb, fieinfo);