2 * Copyright (C) 2008 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
19 #include <linux/sched.h>
21 #include "transaction.h"
24 #include "print-tree.h"
28 /* magic values for the inode_only field in btrfs_log_inode:
30 * LOG_INODE_ALL means to log everything
31 * LOG_INODE_EXISTS means to log just enough to recreate the inode
34 #define LOG_INODE_ALL 0
35 #define LOG_INODE_EXISTS 1
38 * directory trouble cases
40 * 1) on rename or unlink, if the inode being unlinked isn't in the fsync
41 * log, we must force a full commit before doing an fsync of the directory
42 * where the unlink was done.
43 * ---> record transid of last unlink/rename per directory
47 * rename foo/some_dir foo2/some_dir
49 * fsync foo/some_dir/some_file
51 * The fsync above will unlink the original some_dir without recording
52 * it in its new location (foo2). After a crash, some_dir will be gone
53 * unless the fsync of some_file forces a full commit
55 * 2) we must log any new names for any file or dir that is in the fsync
56 * log. ---> check inode while renaming/linking.
58 * 2a) we must log any new names for any file or dir during rename
59 * when the directory they are being removed from was logged.
60 * ---> check inode and old parent dir during rename
62 * 2a is actually the more important variant. With the extra logging
63 * a crash might unlink the old name without recreating the new one
65 * 3) after a crash, we must go through any directories with a link count
66 * of zero and redo the rm -rf
73 * The directory f1 was fully removed from the FS, but fsync was never
74 * called on f1, only its parent dir. After a crash the rm -rf must
75 * be replayed. This must be able to recurse down the entire
76 * directory tree. The inode link count fixup code takes care of the
81 * stages for the tree walking. The first
82 * stage (0) is to only pin down the blocks we find
83 * the second stage (1) is to make sure that all the inodes
84 * we find in the log are created in the subvolume.
86 * The last stage is to deal with directories and links and extents
87 * and all the other fun semantics
89 #define LOG_WALK_PIN_ONLY 0
90 #define LOG_WALK_REPLAY_INODES 1
91 #define LOG_WALK_REPLAY_ALL 2
93 static int btrfs_log_inode(struct btrfs_trans_handle *trans,
94 struct btrfs_root *root, struct inode *inode,
96 static int link_to_fixup_dir(struct btrfs_trans_handle *trans,
97 struct btrfs_root *root,
98 struct btrfs_path *path, u64 objectid);
99 static noinline int replay_dir_deletes(struct btrfs_trans_handle *trans,
100 struct btrfs_root *root,
101 struct btrfs_root *log,
102 struct btrfs_path *path,
103 u64 dirid, int del_all);
106 * tree logging is a special write ahead log used to make sure that
107 * fsyncs and O_SYNCs can happen without doing full tree commits.
109 * Full tree commits are expensive because they require commonly
110 * modified blocks to be recowed, creating many dirty pages in the
111 * extent tree an 4x-6x higher write load than ext3.
113 * Instead of doing a tree commit on every fsync, we use the
114 * key ranges and transaction ids to find items for a given file or directory
115 * that have changed in this transaction. Those items are copied into
116 * a special tree (one per subvolume root), that tree is written to disk
117 * and then the fsync is considered complete.
119 * After a crash, items are copied out of the log-tree back into the
120 * subvolume tree. Any file data extents found are recorded in the extent
121 * allocation tree, and the log-tree freed.
123 * The log tree is read three times, once to pin down all the extents it is
124 * using in ram and once, once to create all the inodes logged in the tree
125 * and once to do all the other items.
129 * start a sub transaction and setup the log tree
130 * this increments the log tree writer count to make the people
131 * syncing the tree wait for us to finish
133 static int start_log_trans(struct btrfs_trans_handle *trans,
134 struct btrfs_root *root)
138 mutex_lock(&root->log_mutex);
139 if (root->log_root) {
141 atomic_inc(&root->log_writers);
142 mutex_unlock(&root->log_mutex);
145 mutex_lock(&root->fs_info->tree_log_mutex);
146 if (!root->fs_info->log_root_tree) {
147 ret = btrfs_init_log_root_tree(trans, root->fs_info);
150 if (!root->log_root) {
151 ret = btrfs_add_log_tree(trans, root);
154 mutex_unlock(&root->fs_info->tree_log_mutex);
156 atomic_inc(&root->log_writers);
157 mutex_unlock(&root->log_mutex);
162 * returns 0 if there was a log transaction running and we were able
163 * to join, or returns -ENOENT if there were not transactions
166 static int join_running_log_trans(struct btrfs_root *root)
174 mutex_lock(&root->log_mutex);
175 if (root->log_root) {
177 atomic_inc(&root->log_writers);
179 mutex_unlock(&root->log_mutex);
184 * This either makes the current running log transaction wait
185 * until you call btrfs_end_log_trans() or it makes any future
186 * log transactions wait until you call btrfs_end_log_trans()
188 int btrfs_pin_log_trans(struct btrfs_root *root)
192 mutex_lock(&root->log_mutex);
193 atomic_inc(&root->log_writers);
194 mutex_unlock(&root->log_mutex);
199 * indicate we're done making changes to the log tree
200 * and wake up anyone waiting to do a sync
202 int btrfs_end_log_trans(struct btrfs_root *root)
204 if (atomic_dec_and_test(&root->log_writers)) {
206 if (waitqueue_active(&root->log_writer_wait))
207 wake_up(&root->log_writer_wait);
214 * the walk control struct is used to pass state down the chain when
215 * processing the log tree. The stage field tells us which part
216 * of the log tree processing we are currently doing. The others
217 * are state fields used for that specific part
219 struct walk_control {
220 /* should we free the extent on disk when done? This is used
221 * at transaction commit time while freeing a log tree
225 /* should we write out the extent buffer? This is used
226 * while flushing the log tree to disk during a sync
230 /* should we wait for the extent buffer io to finish? Also used
231 * while flushing the log tree to disk for a sync
235 /* pin only walk, we record which extents on disk belong to the
240 /* what stage of the replay code we're currently in */
243 /* the root we are currently replaying */
244 struct btrfs_root *replay_dest;
246 /* the trans handle for the current replay */
247 struct btrfs_trans_handle *trans;
249 /* the function that gets used to process blocks we find in the
250 * tree. Note the extent_buffer might not be up to date when it is
251 * passed in, and it must be checked or read if you need the data
254 int (*process_func)(struct btrfs_root *log, struct extent_buffer *eb,
255 struct walk_control *wc, u64 gen);
259 * process_func used to pin down extents, write them or wait on them
261 static int process_one_buffer(struct btrfs_root *log,
262 struct extent_buffer *eb,
263 struct walk_control *wc, u64 gen)
266 btrfs_update_pinned_extents(log->fs_info->extent_root,
267 eb->start, eb->len, 1);
269 if (btrfs_buffer_uptodate(eb, gen)) {
271 btrfs_write_tree_block(eb);
273 btrfs_wait_tree_block_writeback(eb);
279 * Item overwrite used by replay and tree logging. eb, slot and key all refer
280 * to the src data we are copying out.
282 * root is the tree we are copying into, and path is a scratch
283 * path for use in this function (it should be released on entry and
284 * will be released on exit).
286 * If the key is already in the destination tree the existing item is
287 * overwritten. If the existing item isn't big enough, it is extended.
288 * If it is too large, it is truncated.
290 * If the key isn't in the destination yet, a new item is inserted.
292 static noinline int overwrite_item(struct btrfs_trans_handle *trans,
293 struct btrfs_root *root,
294 struct btrfs_path *path,
295 struct extent_buffer *eb, int slot,
296 struct btrfs_key *key)
300 u64 saved_i_size = 0;
301 int save_old_i_size = 0;
302 unsigned long src_ptr;
303 unsigned long dst_ptr;
304 int overwrite_root = 0;
306 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID)
309 item_size = btrfs_item_size_nr(eb, slot);
310 src_ptr = btrfs_item_ptr_offset(eb, slot);
312 /* look for the key in the destination tree */
313 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
317 u32 dst_size = btrfs_item_size_nr(path->nodes[0],
319 if (dst_size != item_size)
322 if (item_size == 0) {
323 btrfs_release_path(root, path);
326 dst_copy = kmalloc(item_size, GFP_NOFS);
327 src_copy = kmalloc(item_size, GFP_NOFS);
329 read_extent_buffer(eb, src_copy, src_ptr, item_size);
331 dst_ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
332 read_extent_buffer(path->nodes[0], dst_copy, dst_ptr,
334 ret = memcmp(dst_copy, src_copy, item_size);
339 * they have the same contents, just return, this saves
340 * us from cowing blocks in the destination tree and doing
341 * extra writes that may not have been done by a previous
345 btrfs_release_path(root, path);
351 btrfs_release_path(root, path);
352 /* try to insert the key into the destination tree */
353 ret = btrfs_insert_empty_item(trans, root, path,
356 /* make sure any existing item is the correct size */
357 if (ret == -EEXIST) {
359 found_size = btrfs_item_size_nr(path->nodes[0],
361 if (found_size > item_size) {
362 btrfs_truncate_item(trans, root, path, item_size, 1);
363 } else if (found_size < item_size) {
364 ret = btrfs_extend_item(trans, root, path,
365 item_size - found_size);
371 dst_ptr = btrfs_item_ptr_offset(path->nodes[0],
374 /* don't overwrite an existing inode if the generation number
375 * was logged as zero. This is done when the tree logging code
376 * is just logging an inode to make sure it exists after recovery.
378 * Also, don't overwrite i_size on directories during replay.
379 * log replay inserts and removes directory items based on the
380 * state of the tree found in the subvolume, and i_size is modified
383 if (key->type == BTRFS_INODE_ITEM_KEY && ret == -EEXIST) {
384 struct btrfs_inode_item *src_item;
385 struct btrfs_inode_item *dst_item;
387 src_item = (struct btrfs_inode_item *)src_ptr;
388 dst_item = (struct btrfs_inode_item *)dst_ptr;
390 if (btrfs_inode_generation(eb, src_item) == 0)
393 if (overwrite_root &&
394 S_ISDIR(btrfs_inode_mode(eb, src_item)) &&
395 S_ISDIR(btrfs_inode_mode(path->nodes[0], dst_item))) {
397 saved_i_size = btrfs_inode_size(path->nodes[0],
402 copy_extent_buffer(path->nodes[0], eb, dst_ptr,
405 if (save_old_i_size) {
406 struct btrfs_inode_item *dst_item;
407 dst_item = (struct btrfs_inode_item *)dst_ptr;
408 btrfs_set_inode_size(path->nodes[0], dst_item, saved_i_size);
411 /* make sure the generation is filled in */
412 if (key->type == BTRFS_INODE_ITEM_KEY) {
413 struct btrfs_inode_item *dst_item;
414 dst_item = (struct btrfs_inode_item *)dst_ptr;
415 if (btrfs_inode_generation(path->nodes[0], dst_item) == 0) {
416 btrfs_set_inode_generation(path->nodes[0], dst_item,
421 btrfs_mark_buffer_dirty(path->nodes[0]);
422 btrfs_release_path(root, path);
427 * simple helper to read an inode off the disk from a given root
428 * This can only be called for subvolume roots and not for the log
430 static noinline struct inode *read_one_inode(struct btrfs_root *root,
434 inode = btrfs_iget_locked(root->fs_info->sb, objectid, root);
435 if (inode->i_state & I_NEW) {
436 BTRFS_I(inode)->root = root;
437 BTRFS_I(inode)->location.objectid = objectid;
438 BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY;
439 BTRFS_I(inode)->location.offset = 0;
440 btrfs_read_locked_inode(inode);
441 unlock_new_inode(inode);
444 if (is_bad_inode(inode)) {
451 /* replays a single extent in 'eb' at 'slot' with 'key' into the
452 * subvolume 'root'. path is released on entry and should be released
455 * extents in the log tree have not been allocated out of the extent
456 * tree yet. So, this completes the allocation, taking a reference
457 * as required if the extent already exists or creating a new extent
458 * if it isn't in the extent allocation tree yet.
460 * The extent is inserted into the file, dropping any existing extents
461 * from the file that overlap the new one.
463 static noinline int replay_one_extent(struct btrfs_trans_handle *trans,
464 struct btrfs_root *root,
465 struct btrfs_path *path,
466 struct extent_buffer *eb, int slot,
467 struct btrfs_key *key)
470 u64 mask = root->sectorsize - 1;
473 u64 start = key->offset;
475 struct btrfs_file_extent_item *item;
476 struct inode *inode = NULL;
480 item = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
481 found_type = btrfs_file_extent_type(eb, item);
483 if (found_type == BTRFS_FILE_EXTENT_REG ||
484 found_type == BTRFS_FILE_EXTENT_PREALLOC)
485 extent_end = start + btrfs_file_extent_num_bytes(eb, item);
486 else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
487 size = btrfs_file_extent_inline_len(eb, item);
488 extent_end = (start + size + mask) & ~mask;
494 inode = read_one_inode(root, key->objectid);
501 * first check to see if we already have this extent in the
502 * file. This must be done before the btrfs_drop_extents run
503 * so we don't try to drop this extent.
505 ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino,
509 (found_type == BTRFS_FILE_EXTENT_REG ||
510 found_type == BTRFS_FILE_EXTENT_PREALLOC)) {
511 struct btrfs_file_extent_item cmp1;
512 struct btrfs_file_extent_item cmp2;
513 struct btrfs_file_extent_item *existing;
514 struct extent_buffer *leaf;
516 leaf = path->nodes[0];
517 existing = btrfs_item_ptr(leaf, path->slots[0],
518 struct btrfs_file_extent_item);
520 read_extent_buffer(eb, &cmp1, (unsigned long)item,
522 read_extent_buffer(leaf, &cmp2, (unsigned long)existing,
526 * we already have a pointer to this exact extent,
527 * we don't have to do anything
529 if (memcmp(&cmp1, &cmp2, sizeof(cmp1)) == 0) {
530 btrfs_release_path(root, path);
534 btrfs_release_path(root, path);
536 saved_nbytes = inode_get_bytes(inode);
537 /* drop any overlapping extents */
538 ret = btrfs_drop_extents(trans, root, inode,
539 start, extent_end, start, &alloc_hint);
542 if (found_type == BTRFS_FILE_EXTENT_REG ||
543 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
544 unsigned long dest_offset;
545 struct btrfs_key ins;
547 ret = btrfs_insert_empty_item(trans, root, path, key,
550 dest_offset = btrfs_item_ptr_offset(path->nodes[0],
552 copy_extent_buffer(path->nodes[0], eb, dest_offset,
553 (unsigned long)item, sizeof(*item));
555 ins.objectid = btrfs_file_extent_disk_bytenr(eb, item);
556 ins.offset = btrfs_file_extent_disk_num_bytes(eb, item);
557 ins.type = BTRFS_EXTENT_ITEM_KEY;
559 if (ins.objectid > 0) {
562 LIST_HEAD(ordered_sums);
564 * is this extent already allocated in the extent
565 * allocation tree? If so, just add a reference
567 ret = btrfs_lookup_extent(root, ins.objectid,
570 ret = btrfs_inc_extent_ref(trans, root,
571 ins.objectid, ins.offset,
572 path->nodes[0]->start,
573 root->root_key.objectid,
574 trans->transid, key->objectid);
577 * insert the extent pointer in the extent
580 ret = btrfs_alloc_logged_extent(trans, root,
581 path->nodes[0]->start,
582 root->root_key.objectid,
583 trans->transid, key->objectid,
587 btrfs_release_path(root, path);
589 if (btrfs_file_extent_compression(eb, item)) {
590 csum_start = ins.objectid;
591 csum_end = csum_start + ins.offset;
593 csum_start = ins.objectid +
594 btrfs_file_extent_offset(eb, item);
595 csum_end = csum_start +
596 btrfs_file_extent_num_bytes(eb, item);
599 ret = btrfs_lookup_csums_range(root->log_root,
600 csum_start, csum_end - 1,
603 while (!list_empty(&ordered_sums)) {
604 struct btrfs_ordered_sum *sums;
605 sums = list_entry(ordered_sums.next,
606 struct btrfs_ordered_sum,
608 ret = btrfs_csum_file_blocks(trans,
609 root->fs_info->csum_root,
612 list_del(&sums->list);
616 btrfs_release_path(root, path);
618 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
619 /* inline extents are easy, we just overwrite them */
620 ret = overwrite_item(trans, root, path, eb, slot, key);
624 inode_set_bytes(inode, saved_nbytes);
625 btrfs_update_inode(trans, root, inode);
633 * when cleaning up conflicts between the directory names in the
634 * subvolume, directory names in the log and directory names in the
635 * inode back references, we may have to unlink inodes from directories.
637 * This is a helper function to do the unlink of a specific directory
640 static noinline int drop_one_dir_item(struct btrfs_trans_handle *trans,
641 struct btrfs_root *root,
642 struct btrfs_path *path,
644 struct btrfs_dir_item *di)
649 struct extent_buffer *leaf;
650 struct btrfs_key location;
653 leaf = path->nodes[0];
655 btrfs_dir_item_key_to_cpu(leaf, di, &location);
656 name_len = btrfs_dir_name_len(leaf, di);
657 name = kmalloc(name_len, GFP_NOFS);
658 read_extent_buffer(leaf, name, (unsigned long)(di + 1), name_len);
659 btrfs_release_path(root, path);
661 inode = read_one_inode(root, location.objectid);
664 ret = link_to_fixup_dir(trans, root, path, location.objectid);
667 ret = btrfs_unlink_inode(trans, root, dir, inode, name, name_len);
676 * helper function to see if a given name and sequence number found
677 * in an inode back reference are already in a directory and correctly
678 * point to this inode
680 static noinline int inode_in_dir(struct btrfs_root *root,
681 struct btrfs_path *path,
682 u64 dirid, u64 objectid, u64 index,
683 const char *name, int name_len)
685 struct btrfs_dir_item *di;
686 struct btrfs_key location;
689 di = btrfs_lookup_dir_index_item(NULL, root, path, dirid,
690 index, name, name_len, 0);
691 if (di && !IS_ERR(di)) {
692 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location);
693 if (location.objectid != objectid)
697 btrfs_release_path(root, path);
699 di = btrfs_lookup_dir_item(NULL, root, path, dirid, name, name_len, 0);
700 if (di && !IS_ERR(di)) {
701 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location);
702 if (location.objectid != objectid)
708 btrfs_release_path(root, path);
713 * helper function to check a log tree for a named back reference in
714 * an inode. This is used to decide if a back reference that is
715 * found in the subvolume conflicts with what we find in the log.
717 * inode backreferences may have multiple refs in a single item,
718 * during replay we process one reference at a time, and we don't
719 * want to delete valid links to a file from the subvolume if that
720 * link is also in the log.
722 static noinline int backref_in_log(struct btrfs_root *log,
723 struct btrfs_key *key,
724 char *name, int namelen)
726 struct btrfs_path *path;
727 struct btrfs_inode_ref *ref;
729 unsigned long ptr_end;
730 unsigned long name_ptr;
736 path = btrfs_alloc_path();
737 ret = btrfs_search_slot(NULL, log, key, path, 0, 0);
741 item_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]);
742 ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
743 ptr_end = ptr + item_size;
744 while (ptr < ptr_end) {
745 ref = (struct btrfs_inode_ref *)ptr;
746 found_name_len = btrfs_inode_ref_name_len(path->nodes[0], ref);
747 if (found_name_len == namelen) {
748 name_ptr = (unsigned long)(ref + 1);
749 ret = memcmp_extent_buffer(path->nodes[0], name,
756 ptr = (unsigned long)(ref + 1) + found_name_len;
759 btrfs_free_path(path);
765 * replay one inode back reference item found in the log tree.
766 * eb, slot and key refer to the buffer and key found in the log tree.
767 * root is the destination we are replaying into, and path is for temp
768 * use by this function. (it should be released on return).
770 static noinline int add_inode_ref(struct btrfs_trans_handle *trans,
771 struct btrfs_root *root,
772 struct btrfs_root *log,
773 struct btrfs_path *path,
774 struct extent_buffer *eb, int slot,
775 struct btrfs_key *key)
779 struct btrfs_key location;
780 struct btrfs_inode_ref *ref;
781 struct btrfs_dir_item *di;
785 unsigned long ref_ptr;
786 unsigned long ref_end;
788 location.objectid = key->objectid;
789 location.type = BTRFS_INODE_ITEM_KEY;
793 * it is possible that we didn't log all the parent directories
794 * for a given inode. If we don't find the dir, just don't
795 * copy the back ref in. The link count fixup code will take
798 dir = read_one_inode(root, key->offset);
802 inode = read_one_inode(root, key->objectid);
805 ref_ptr = btrfs_item_ptr_offset(eb, slot);
806 ref_end = ref_ptr + btrfs_item_size_nr(eb, slot);
809 ref = (struct btrfs_inode_ref *)ref_ptr;
811 namelen = btrfs_inode_ref_name_len(eb, ref);
812 name = kmalloc(namelen, GFP_NOFS);
815 read_extent_buffer(eb, name, (unsigned long)(ref + 1), namelen);
817 /* if we already have a perfect match, we're done */
818 if (inode_in_dir(root, path, dir->i_ino, inode->i_ino,
819 btrfs_inode_ref_index(eb, ref),
825 * look for a conflicting back reference in the metadata.
826 * if we find one we have to unlink that name of the file
827 * before we add our new link. Later on, we overwrite any
828 * existing back reference, and we don't want to create
829 * dangling pointers in the directory.
832 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
836 struct btrfs_inode_ref *victim_ref;
838 unsigned long ptr_end;
839 struct extent_buffer *leaf = path->nodes[0];
841 /* are we trying to overwrite a back ref for the root directory
842 * if so, just jump out, we're done
844 if (key->objectid == key->offset)
847 /* check all the names in this back reference to see
848 * if they are in the log. if so, we allow them to stay
849 * otherwise they must be unlinked as a conflict
851 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
852 ptr_end = ptr + btrfs_item_size_nr(leaf, path->slots[0]);
853 while (ptr < ptr_end) {
854 victim_ref = (struct btrfs_inode_ref *)ptr;
855 victim_name_len = btrfs_inode_ref_name_len(leaf,
857 victim_name = kmalloc(victim_name_len, GFP_NOFS);
858 BUG_ON(!victim_name);
860 read_extent_buffer(leaf, victim_name,
861 (unsigned long)(victim_ref + 1),
864 if (!backref_in_log(log, key, victim_name,
866 btrfs_inc_nlink(inode);
867 btrfs_release_path(root, path);
869 ret = btrfs_unlink_inode(trans, root, dir,
873 btrfs_release_path(root, path);
877 ptr = (unsigned long)(victim_ref + 1) + victim_name_len;
881 btrfs_release_path(root, path);
883 /* look for a conflicting sequence number */
884 di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
885 btrfs_inode_ref_index(eb, ref),
887 if (di && !IS_ERR(di)) {
888 ret = drop_one_dir_item(trans, root, path, dir, di);
891 btrfs_release_path(root, path);
894 /* look for a conflicting name */
895 di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
897 if (di && !IS_ERR(di)) {
898 ret = drop_one_dir_item(trans, root, path, dir, di);
901 btrfs_release_path(root, path);
903 /* insert our name */
904 ret = btrfs_add_link(trans, dir, inode, name, namelen, 0,
905 btrfs_inode_ref_index(eb, ref));
908 btrfs_update_inode(trans, root, inode);
911 ref_ptr = (unsigned long)(ref + 1) + namelen;
913 if (ref_ptr < ref_end)
916 /* finally write the back reference in the inode */
917 ret = overwrite_item(trans, root, path, eb, slot, key);
921 btrfs_release_path(root, path);
928 * There are a few corners where the link count of the file can't
929 * be properly maintained during replay. So, instead of adding
930 * lots of complexity to the log code, we just scan the backrefs
931 * for any file that has been through replay.
933 * The scan will update the link count on the inode to reflect the
934 * number of back refs found. If it goes down to zero, the iput
935 * will free the inode.
937 static noinline int fixup_inode_link_count(struct btrfs_trans_handle *trans,
938 struct btrfs_root *root,
941 struct btrfs_path *path;
943 struct btrfs_key key;
946 unsigned long ptr_end;
949 key.objectid = inode->i_ino;
950 key.type = BTRFS_INODE_REF_KEY;
951 key.offset = (u64)-1;
953 path = btrfs_alloc_path();
956 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
960 if (path->slots[0] == 0)
964 btrfs_item_key_to_cpu(path->nodes[0], &key,
966 if (key.objectid != inode->i_ino ||
967 key.type != BTRFS_INODE_REF_KEY)
969 ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
970 ptr_end = ptr + btrfs_item_size_nr(path->nodes[0],
972 while (ptr < ptr_end) {
973 struct btrfs_inode_ref *ref;
975 ref = (struct btrfs_inode_ref *)ptr;
976 name_len = btrfs_inode_ref_name_len(path->nodes[0],
978 ptr = (unsigned long)(ref + 1) + name_len;
985 btrfs_release_path(root, path);
987 btrfs_release_path(root, path);
988 if (nlink != inode->i_nlink) {
989 inode->i_nlink = nlink;
990 btrfs_update_inode(trans, root, inode);
992 BTRFS_I(inode)->index_cnt = (u64)-1;
994 if (inode->i_nlink == 0 && S_ISDIR(inode->i_mode)) {
995 ret = replay_dir_deletes(trans, root, NULL, path,
999 btrfs_free_path(path);
1004 static noinline int fixup_inode_link_counts(struct btrfs_trans_handle *trans,
1005 struct btrfs_root *root,
1006 struct btrfs_path *path)
1009 struct btrfs_key key;
1010 struct inode *inode;
1012 key.objectid = BTRFS_TREE_LOG_FIXUP_OBJECTID;
1013 key.type = BTRFS_ORPHAN_ITEM_KEY;
1014 key.offset = (u64)-1;
1016 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1021 if (path->slots[0] == 0)
1026 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1027 if (key.objectid != BTRFS_TREE_LOG_FIXUP_OBJECTID ||
1028 key.type != BTRFS_ORPHAN_ITEM_KEY)
1031 ret = btrfs_del_item(trans, root, path);
1034 btrfs_release_path(root, path);
1035 inode = read_one_inode(root, key.offset);
1038 ret = fixup_inode_link_count(trans, root, inode);
1044 * fixup on a directory may create new entries,
1045 * make sure we always look for the highset possible
1048 key.offset = (u64)-1;
1050 btrfs_release_path(root, path);
1056 * record a given inode in the fixup dir so we can check its link
1057 * count when replay is done. The link count is incremented here
1058 * so the inode won't go away until we check it
1060 static noinline int link_to_fixup_dir(struct btrfs_trans_handle *trans,
1061 struct btrfs_root *root,
1062 struct btrfs_path *path,
1065 struct btrfs_key key;
1067 struct inode *inode;
1069 inode = read_one_inode(root, objectid);
1072 key.objectid = BTRFS_TREE_LOG_FIXUP_OBJECTID;
1073 btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
1074 key.offset = objectid;
1076 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1078 btrfs_release_path(root, path);
1080 btrfs_inc_nlink(inode);
1081 btrfs_update_inode(trans, root, inode);
1082 } else if (ret == -EEXIST) {
1093 * when replaying the log for a directory, we only insert names
1094 * for inodes that actually exist. This means an fsync on a directory
1095 * does not implicitly fsync all the new files in it
1097 static noinline int insert_one_name(struct btrfs_trans_handle *trans,
1098 struct btrfs_root *root,
1099 struct btrfs_path *path,
1100 u64 dirid, u64 index,
1101 char *name, int name_len, u8 type,
1102 struct btrfs_key *location)
1104 struct inode *inode;
1108 inode = read_one_inode(root, location->objectid);
1112 dir = read_one_inode(root, dirid);
1117 ret = btrfs_add_link(trans, dir, inode, name, name_len, 1, index);
1119 /* FIXME, put inode into FIXUP list */
1127 * take a single entry in a log directory item and replay it into
1130 * if a conflicting item exists in the subdirectory already,
1131 * the inode it points to is unlinked and put into the link count
1134 * If a name from the log points to a file or directory that does
1135 * not exist in the FS, it is skipped. fsyncs on directories
1136 * do not force down inodes inside that directory, just changes to the
1137 * names or unlinks in a directory.
1139 static noinline int replay_one_name(struct btrfs_trans_handle *trans,
1140 struct btrfs_root *root,
1141 struct btrfs_path *path,
1142 struct extent_buffer *eb,
1143 struct btrfs_dir_item *di,
1144 struct btrfs_key *key)
1148 struct btrfs_dir_item *dst_di;
1149 struct btrfs_key found_key;
1150 struct btrfs_key log_key;
1156 dir = read_one_inode(root, key->objectid);
1159 name_len = btrfs_dir_name_len(eb, di);
1160 name = kmalloc(name_len, GFP_NOFS);
1161 log_type = btrfs_dir_type(eb, di);
1162 read_extent_buffer(eb, name, (unsigned long)(di + 1),
1165 btrfs_dir_item_key_to_cpu(eb, di, &log_key);
1166 exists = btrfs_lookup_inode(trans, root, path, &log_key, 0);
1171 btrfs_release_path(root, path);
1173 if (key->type == BTRFS_DIR_ITEM_KEY) {
1174 dst_di = btrfs_lookup_dir_item(trans, root, path, key->objectid,
1176 } else if (key->type == BTRFS_DIR_INDEX_KEY) {
1177 dst_di = btrfs_lookup_dir_index_item(trans, root, path,
1184 if (!dst_di || IS_ERR(dst_di)) {
1185 /* we need a sequence number to insert, so we only
1186 * do inserts for the BTRFS_DIR_INDEX_KEY types
1188 if (key->type != BTRFS_DIR_INDEX_KEY)
1193 btrfs_dir_item_key_to_cpu(path->nodes[0], dst_di, &found_key);
1194 /* the existing item matches the logged item */
1195 if (found_key.objectid == log_key.objectid &&
1196 found_key.type == log_key.type &&
1197 found_key.offset == log_key.offset &&
1198 btrfs_dir_type(path->nodes[0], dst_di) == log_type) {
1203 * don't drop the conflicting directory entry if the inode
1204 * for the new entry doesn't exist
1209 ret = drop_one_dir_item(trans, root, path, dir, dst_di);
1212 if (key->type == BTRFS_DIR_INDEX_KEY)
1215 btrfs_release_path(root, path);
1221 btrfs_release_path(root, path);
1222 ret = insert_one_name(trans, root, path, key->objectid, key->offset,
1223 name, name_len, log_type, &log_key);
1225 if (ret && ret != -ENOENT)
1231 * find all the names in a directory item and reconcile them into
1232 * the subvolume. Only BTRFS_DIR_ITEM_KEY types will have more than
1233 * one name in a directory item, but the same code gets used for
1234 * both directory index types
1236 static noinline int replay_one_dir_item(struct btrfs_trans_handle *trans,
1237 struct btrfs_root *root,
1238 struct btrfs_path *path,
1239 struct extent_buffer *eb, int slot,
1240 struct btrfs_key *key)
1243 u32 item_size = btrfs_item_size_nr(eb, slot);
1244 struct btrfs_dir_item *di;
1247 unsigned long ptr_end;
1249 ptr = btrfs_item_ptr_offset(eb, slot);
1250 ptr_end = ptr + item_size;
1251 while (ptr < ptr_end) {
1252 di = (struct btrfs_dir_item *)ptr;
1253 name_len = btrfs_dir_name_len(eb, di);
1254 ret = replay_one_name(trans, root, path, eb, di, key);
1256 ptr = (unsigned long)(di + 1);
1263 * directory replay has two parts. There are the standard directory
1264 * items in the log copied from the subvolume, and range items
1265 * created in the log while the subvolume was logged.
1267 * The range items tell us which parts of the key space the log
1268 * is authoritative for. During replay, if a key in the subvolume
1269 * directory is in a logged range item, but not actually in the log
1270 * that means it was deleted from the directory before the fsync
1271 * and should be removed.
1273 static noinline int find_dir_range(struct btrfs_root *root,
1274 struct btrfs_path *path,
1275 u64 dirid, int key_type,
1276 u64 *start_ret, u64 *end_ret)
1278 struct btrfs_key key;
1280 struct btrfs_dir_log_item *item;
1284 if (*start_ret == (u64)-1)
1287 key.objectid = dirid;
1288 key.type = key_type;
1289 key.offset = *start_ret;
1291 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1295 if (path->slots[0] == 0)
1300 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1302 if (key.type != key_type || key.objectid != dirid) {
1306 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
1307 struct btrfs_dir_log_item);
1308 found_end = btrfs_dir_log_end(path->nodes[0], item);
1310 if (*start_ret >= key.offset && *start_ret <= found_end) {
1312 *start_ret = key.offset;
1313 *end_ret = found_end;
1318 /* check the next slot in the tree to see if it is a valid item */
1319 nritems = btrfs_header_nritems(path->nodes[0]);
1320 if (path->slots[0] >= nritems) {
1321 ret = btrfs_next_leaf(root, path);
1328 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1330 if (key.type != key_type || key.objectid != dirid) {
1334 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
1335 struct btrfs_dir_log_item);
1336 found_end = btrfs_dir_log_end(path->nodes[0], item);
1337 *start_ret = key.offset;
1338 *end_ret = found_end;
1341 btrfs_release_path(root, path);
1346 * this looks for a given directory item in the log. If the directory
1347 * item is not in the log, the item is removed and the inode it points
1350 static noinline int check_item_in_log(struct btrfs_trans_handle *trans,
1351 struct btrfs_root *root,
1352 struct btrfs_root *log,
1353 struct btrfs_path *path,
1354 struct btrfs_path *log_path,
1356 struct btrfs_key *dir_key)
1359 struct extent_buffer *eb;
1362 struct btrfs_dir_item *di;
1363 struct btrfs_dir_item *log_di;
1366 unsigned long ptr_end;
1368 struct inode *inode;
1369 struct btrfs_key location;
1372 eb = path->nodes[0];
1373 slot = path->slots[0];
1374 item_size = btrfs_item_size_nr(eb, slot);
1375 ptr = btrfs_item_ptr_offset(eb, slot);
1376 ptr_end = ptr + item_size;
1377 while (ptr < ptr_end) {
1378 di = (struct btrfs_dir_item *)ptr;
1379 name_len = btrfs_dir_name_len(eb, di);
1380 name = kmalloc(name_len, GFP_NOFS);
1385 read_extent_buffer(eb, name, (unsigned long)(di + 1),
1388 if (log && dir_key->type == BTRFS_DIR_ITEM_KEY) {
1389 log_di = btrfs_lookup_dir_item(trans, log, log_path,
1392 } else if (log && dir_key->type == BTRFS_DIR_INDEX_KEY) {
1393 log_di = btrfs_lookup_dir_index_item(trans, log,
1399 if (!log_di || IS_ERR(log_di)) {
1400 btrfs_dir_item_key_to_cpu(eb, di, &location);
1401 btrfs_release_path(root, path);
1402 btrfs_release_path(log, log_path);
1403 inode = read_one_inode(root, location.objectid);
1406 ret = link_to_fixup_dir(trans, root,
1407 path, location.objectid);
1409 btrfs_inc_nlink(inode);
1410 ret = btrfs_unlink_inode(trans, root, dir, inode,
1416 /* there might still be more names under this key
1417 * check and repeat if required
1419 ret = btrfs_search_slot(NULL, root, dir_key, path,
1426 btrfs_release_path(log, log_path);
1429 ptr = (unsigned long)(di + 1);
1434 btrfs_release_path(root, path);
1435 btrfs_release_path(log, log_path);
1440 * deletion replay happens before we copy any new directory items
1441 * out of the log or out of backreferences from inodes. It
1442 * scans the log to find ranges of keys that log is authoritative for,
1443 * and then scans the directory to find items in those ranges that are
1444 * not present in the log.
1446 * Anything we don't find in the log is unlinked and removed from the
1449 static noinline int replay_dir_deletes(struct btrfs_trans_handle *trans,
1450 struct btrfs_root *root,
1451 struct btrfs_root *log,
1452 struct btrfs_path *path,
1453 u64 dirid, int del_all)
1457 int key_type = BTRFS_DIR_LOG_ITEM_KEY;
1459 struct btrfs_key dir_key;
1460 struct btrfs_key found_key;
1461 struct btrfs_path *log_path;
1464 dir_key.objectid = dirid;
1465 dir_key.type = BTRFS_DIR_ITEM_KEY;
1466 log_path = btrfs_alloc_path();
1470 dir = read_one_inode(root, dirid);
1471 /* it isn't an error if the inode isn't there, that can happen
1472 * because we replay the deletes before we copy in the inode item
1476 btrfs_free_path(log_path);
1484 range_end = (u64)-1;
1486 ret = find_dir_range(log, path, dirid, key_type,
1487 &range_start, &range_end);
1492 dir_key.offset = range_start;
1495 ret = btrfs_search_slot(NULL, root, &dir_key, path,
1500 nritems = btrfs_header_nritems(path->nodes[0]);
1501 if (path->slots[0] >= nritems) {
1502 ret = btrfs_next_leaf(root, path);
1506 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1508 if (found_key.objectid != dirid ||
1509 found_key.type != dir_key.type)
1512 if (found_key.offset > range_end)
1515 ret = check_item_in_log(trans, root, log, path,
1519 if (found_key.offset == (u64)-1)
1521 dir_key.offset = found_key.offset + 1;
1523 btrfs_release_path(root, path);
1524 if (range_end == (u64)-1)
1526 range_start = range_end + 1;
1531 if (key_type == BTRFS_DIR_LOG_ITEM_KEY) {
1532 key_type = BTRFS_DIR_LOG_INDEX_KEY;
1533 dir_key.type = BTRFS_DIR_INDEX_KEY;
1534 btrfs_release_path(root, path);
1538 btrfs_release_path(root, path);
1539 btrfs_free_path(log_path);
1545 * the process_func used to replay items from the log tree. This
1546 * gets called in two different stages. The first stage just looks
1547 * for inodes and makes sure they are all copied into the subvolume.
1549 * The second stage copies all the other item types from the log into
1550 * the subvolume. The two stage approach is slower, but gets rid of
1551 * lots of complexity around inodes referencing other inodes that exist
1552 * only in the log (references come from either directory items or inode
1555 static int replay_one_buffer(struct btrfs_root *log, struct extent_buffer *eb,
1556 struct walk_control *wc, u64 gen)
1559 struct btrfs_path *path;
1560 struct btrfs_root *root = wc->replay_dest;
1561 struct btrfs_key key;
1567 btrfs_read_buffer(eb, gen);
1569 level = btrfs_header_level(eb);
1574 path = btrfs_alloc_path();
1577 nritems = btrfs_header_nritems(eb);
1578 for (i = 0; i < nritems; i++) {
1579 btrfs_item_key_to_cpu(eb, &key, i);
1580 item_size = btrfs_item_size_nr(eb, i);
1582 /* inode keys are done during the first stage */
1583 if (key.type == BTRFS_INODE_ITEM_KEY &&
1584 wc->stage == LOG_WALK_REPLAY_INODES) {
1585 struct inode *inode;
1586 struct btrfs_inode_item *inode_item;
1589 inode_item = btrfs_item_ptr(eb, i,
1590 struct btrfs_inode_item);
1591 mode = btrfs_inode_mode(eb, inode_item);
1592 if (S_ISDIR(mode)) {
1593 ret = replay_dir_deletes(wc->trans,
1594 root, log, path, key.objectid, 0);
1597 ret = overwrite_item(wc->trans, root, path,
1601 /* for regular files, truncate away
1602 * extents past the new EOF
1604 if (S_ISREG(mode)) {
1605 inode = read_one_inode(root,
1609 ret = btrfs_truncate_inode_items(wc->trans,
1610 root, inode, inode->i_size,
1611 BTRFS_EXTENT_DATA_KEY);
1614 /* if the nlink count is zero here, the iput
1615 * will free the inode. We bump it to make
1616 * sure it doesn't get freed until the link
1617 * count fixup is done
1619 if (inode->i_nlink == 0) {
1620 btrfs_inc_nlink(inode);
1621 btrfs_update_inode(wc->trans,
1626 ret = link_to_fixup_dir(wc->trans, root,
1627 path, key.objectid);
1630 if (wc->stage < LOG_WALK_REPLAY_ALL)
1633 /* these keys are simply copied */
1634 if (key.type == BTRFS_XATTR_ITEM_KEY) {
1635 ret = overwrite_item(wc->trans, root, path,
1638 } else if (key.type == BTRFS_INODE_REF_KEY) {
1639 ret = add_inode_ref(wc->trans, root, log, path,
1641 BUG_ON(ret && ret != -ENOENT);
1642 } else if (key.type == BTRFS_EXTENT_DATA_KEY) {
1643 ret = replay_one_extent(wc->trans, root, path,
1646 } else if (key.type == BTRFS_DIR_ITEM_KEY ||
1647 key.type == BTRFS_DIR_INDEX_KEY) {
1648 ret = replay_one_dir_item(wc->trans, root, path,
1653 btrfs_free_path(path);
1657 static noinline int walk_down_log_tree(struct btrfs_trans_handle *trans,
1658 struct btrfs_root *root,
1659 struct btrfs_path *path, int *level,
1660 struct walk_control *wc)
1666 struct extent_buffer *next;
1667 struct extent_buffer *cur;
1668 struct extent_buffer *parent;
1672 WARN_ON(*level < 0);
1673 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1675 while (*level > 0) {
1676 WARN_ON(*level < 0);
1677 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1678 cur = path->nodes[*level];
1680 if (btrfs_header_level(cur) != *level)
1683 if (path->slots[*level] >=
1684 btrfs_header_nritems(cur))
1687 bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
1688 ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
1689 blocksize = btrfs_level_size(root, *level - 1);
1691 parent = path->nodes[*level];
1692 root_owner = btrfs_header_owner(parent);
1693 root_gen = btrfs_header_generation(parent);
1695 next = btrfs_find_create_tree_block(root, bytenr, blocksize);
1697 wc->process_func(root, next, wc, ptr_gen);
1700 path->slots[*level]++;
1702 btrfs_read_buffer(next, ptr_gen);
1704 btrfs_tree_lock(next);
1705 clean_tree_block(trans, root, next);
1706 btrfs_set_lock_blocking(next);
1707 btrfs_wait_tree_block_writeback(next);
1708 btrfs_tree_unlock(next);
1710 ret = btrfs_drop_leaf_ref(trans, root, next);
1713 WARN_ON(root_owner !=
1714 BTRFS_TREE_LOG_OBJECTID);
1715 ret = btrfs_free_reserved_extent(root,
1719 free_extent_buffer(next);
1722 btrfs_read_buffer(next, ptr_gen);
1724 WARN_ON(*level <= 0);
1725 if (path->nodes[*level-1])
1726 free_extent_buffer(path->nodes[*level-1]);
1727 path->nodes[*level-1] = next;
1728 *level = btrfs_header_level(next);
1729 path->slots[*level] = 0;
1732 WARN_ON(*level < 0);
1733 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1735 if (path->nodes[*level] == root->node)
1736 parent = path->nodes[*level];
1738 parent = path->nodes[*level + 1];
1740 bytenr = path->nodes[*level]->start;
1742 blocksize = btrfs_level_size(root, *level);
1743 root_owner = btrfs_header_owner(parent);
1744 root_gen = btrfs_header_generation(parent);
1746 wc->process_func(root, path->nodes[*level], wc,
1747 btrfs_header_generation(path->nodes[*level]));
1750 next = path->nodes[*level];
1751 btrfs_tree_lock(next);
1752 clean_tree_block(trans, root, next);
1753 btrfs_set_lock_blocking(next);
1754 btrfs_wait_tree_block_writeback(next);
1755 btrfs_tree_unlock(next);
1758 ret = btrfs_drop_leaf_ref(trans, root, next);
1761 WARN_ON(root_owner != BTRFS_TREE_LOG_OBJECTID);
1762 ret = btrfs_free_reserved_extent(root, bytenr, blocksize);
1765 free_extent_buffer(path->nodes[*level]);
1766 path->nodes[*level] = NULL;
1773 static noinline int walk_up_log_tree(struct btrfs_trans_handle *trans,
1774 struct btrfs_root *root,
1775 struct btrfs_path *path, int *level,
1776 struct walk_control *wc)
1784 for (i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
1785 slot = path->slots[i];
1786 if (slot < btrfs_header_nritems(path->nodes[i]) - 1) {
1787 struct extent_buffer *node;
1788 node = path->nodes[i];
1791 WARN_ON(*level == 0);
1794 struct extent_buffer *parent;
1795 if (path->nodes[*level] == root->node)
1796 parent = path->nodes[*level];
1798 parent = path->nodes[*level + 1];
1800 root_owner = btrfs_header_owner(parent);
1801 root_gen = btrfs_header_generation(parent);
1802 wc->process_func(root, path->nodes[*level], wc,
1803 btrfs_header_generation(path->nodes[*level]));
1805 struct extent_buffer *next;
1807 next = path->nodes[*level];
1809 btrfs_tree_lock(next);
1810 clean_tree_block(trans, root, next);
1811 btrfs_set_lock_blocking(next);
1812 btrfs_wait_tree_block_writeback(next);
1813 btrfs_tree_unlock(next);
1816 ret = btrfs_drop_leaf_ref(trans, root,
1821 WARN_ON(root_owner != BTRFS_TREE_LOG_OBJECTID);
1822 ret = btrfs_free_reserved_extent(root,
1823 path->nodes[*level]->start,
1824 path->nodes[*level]->len);
1827 free_extent_buffer(path->nodes[*level]);
1828 path->nodes[*level] = NULL;
1836 * drop the reference count on the tree rooted at 'snap'. This traverses
1837 * the tree freeing any blocks that have a ref count of zero after being
1840 static int walk_log_tree(struct btrfs_trans_handle *trans,
1841 struct btrfs_root *log, struct walk_control *wc)
1846 struct btrfs_path *path;
1850 path = btrfs_alloc_path();
1853 level = btrfs_header_level(log->node);
1855 path->nodes[level] = log->node;
1856 extent_buffer_get(log->node);
1857 path->slots[level] = 0;
1860 wret = walk_down_log_tree(trans, log, path, &level, wc);
1866 wret = walk_up_log_tree(trans, log, path, &level, wc);
1873 /* was the root node processed? if not, catch it here */
1874 if (path->nodes[orig_level]) {
1875 wc->process_func(log, path->nodes[orig_level], wc,
1876 btrfs_header_generation(path->nodes[orig_level]));
1878 struct extent_buffer *next;
1880 next = path->nodes[orig_level];
1882 btrfs_tree_lock(next);
1883 clean_tree_block(trans, log, next);
1884 btrfs_set_lock_blocking(next);
1885 btrfs_wait_tree_block_writeback(next);
1886 btrfs_tree_unlock(next);
1888 if (orig_level == 0) {
1889 ret = btrfs_drop_leaf_ref(trans, log,
1893 WARN_ON(log->root_key.objectid !=
1894 BTRFS_TREE_LOG_OBJECTID);
1895 ret = btrfs_free_reserved_extent(log, next->start,
1901 for (i = 0; i <= orig_level; i++) {
1902 if (path->nodes[i]) {
1903 free_extent_buffer(path->nodes[i]);
1904 path->nodes[i] = NULL;
1907 btrfs_free_path(path);
1912 * helper function to update the item for a given subvolumes log root
1913 * in the tree of log roots
1915 static int update_log_root(struct btrfs_trans_handle *trans,
1916 struct btrfs_root *log)
1920 if (log->log_transid == 1) {
1921 /* insert root item on the first sync */
1922 ret = btrfs_insert_root(trans, log->fs_info->log_root_tree,
1923 &log->root_key, &log->root_item);
1925 ret = btrfs_update_root(trans, log->fs_info->log_root_tree,
1926 &log->root_key, &log->root_item);
1931 static int wait_log_commit(struct btrfs_trans_handle *trans,
1932 struct btrfs_root *root, unsigned long transid)
1935 int index = transid % 2;
1938 * we only allow two pending log transactions at a time,
1939 * so we know that if ours is more than 2 older than the
1940 * current transaction, we're done
1943 prepare_to_wait(&root->log_commit_wait[index],
1944 &wait, TASK_UNINTERRUPTIBLE);
1945 mutex_unlock(&root->log_mutex);
1947 if (root->fs_info->last_trans_log_full_commit !=
1948 trans->transid && root->log_transid < transid + 2 &&
1949 atomic_read(&root->log_commit[index]))
1952 finish_wait(&root->log_commit_wait[index], &wait);
1953 mutex_lock(&root->log_mutex);
1954 } while (root->log_transid < transid + 2 &&
1955 atomic_read(&root->log_commit[index]));
1959 static int wait_for_writer(struct btrfs_trans_handle *trans,
1960 struct btrfs_root *root)
1963 while (atomic_read(&root->log_writers)) {
1964 prepare_to_wait(&root->log_writer_wait,
1965 &wait, TASK_UNINTERRUPTIBLE);
1966 mutex_unlock(&root->log_mutex);
1967 if (root->fs_info->last_trans_log_full_commit !=
1968 trans->transid && atomic_read(&root->log_writers))
1970 mutex_lock(&root->log_mutex);
1971 finish_wait(&root->log_writer_wait, &wait);
1977 * btrfs_sync_log does sends a given tree log down to the disk and
1978 * updates the super blocks to record it. When this call is done,
1979 * you know that any inodes previously logged are safely on disk only
1982 * Any other return value means you need to call btrfs_commit_transaction.
1983 * Some of the edge cases for fsyncing directories that have had unlinks
1984 * or renames done in the past mean that sometimes the only safe
1985 * fsync is to commit the whole FS. When btrfs_sync_log returns -EAGAIN,
1986 * that has happened.
1988 int btrfs_sync_log(struct btrfs_trans_handle *trans,
1989 struct btrfs_root *root)
1994 struct btrfs_root *log = root->log_root;
1995 struct btrfs_root *log_root_tree = root->fs_info->log_root_tree;
1997 mutex_lock(&root->log_mutex);
1998 index1 = root->log_transid % 2;
1999 if (atomic_read(&root->log_commit[index1])) {
2000 wait_log_commit(trans, root, root->log_transid);
2001 mutex_unlock(&root->log_mutex);
2004 atomic_set(&root->log_commit[index1], 1);
2006 /* wait for previous tree log sync to complete */
2007 if (atomic_read(&root->log_commit[(index1 + 1) % 2]))
2008 wait_log_commit(trans, root, root->log_transid - 1);
2011 unsigned long batch = root->log_batch;
2012 mutex_unlock(&root->log_mutex);
2013 schedule_timeout_uninterruptible(1);
2014 mutex_lock(&root->log_mutex);
2016 wait_for_writer(trans, root);
2017 if (batch == root->log_batch)
2021 /* bail out if we need to do a full commit */
2022 if (root->fs_info->last_trans_log_full_commit == trans->transid) {
2024 mutex_unlock(&root->log_mutex);
2028 ret = btrfs_write_and_wait_marked_extents(log, &log->dirty_log_pages);
2031 btrfs_set_root_bytenr(&log->root_item, log->node->start);
2032 btrfs_set_root_generation(&log->root_item, trans->transid);
2033 btrfs_set_root_level(&log->root_item, btrfs_header_level(log->node));
2035 root->log_batch = 0;
2036 root->log_transid++;
2037 log->log_transid = root->log_transid;
2040 * log tree has been flushed to disk, new modifications of
2041 * the log will be written to new positions. so it's safe to
2042 * allow log writers to go in.
2044 mutex_unlock(&root->log_mutex);
2046 mutex_lock(&log_root_tree->log_mutex);
2047 log_root_tree->log_batch++;
2048 atomic_inc(&log_root_tree->log_writers);
2049 mutex_unlock(&log_root_tree->log_mutex);
2051 ret = update_log_root(trans, log);
2054 mutex_lock(&log_root_tree->log_mutex);
2055 if (atomic_dec_and_test(&log_root_tree->log_writers)) {
2057 if (waitqueue_active(&log_root_tree->log_writer_wait))
2058 wake_up(&log_root_tree->log_writer_wait);
2061 index2 = log_root_tree->log_transid % 2;
2062 if (atomic_read(&log_root_tree->log_commit[index2])) {
2063 wait_log_commit(trans, log_root_tree,
2064 log_root_tree->log_transid);
2065 mutex_unlock(&log_root_tree->log_mutex);
2068 atomic_set(&log_root_tree->log_commit[index2], 1);
2070 if (atomic_read(&log_root_tree->log_commit[(index2 + 1) % 2])) {
2071 wait_log_commit(trans, log_root_tree,
2072 log_root_tree->log_transid - 1);
2075 wait_for_writer(trans, log_root_tree);
2078 * now that we've moved on to the tree of log tree roots,
2079 * check the full commit flag again
2081 if (root->fs_info->last_trans_log_full_commit == trans->transid) {
2082 mutex_unlock(&log_root_tree->log_mutex);
2084 goto out_wake_log_root;
2087 ret = btrfs_write_and_wait_marked_extents(log_root_tree,
2088 &log_root_tree->dirty_log_pages);
2091 btrfs_set_super_log_root(&root->fs_info->super_for_commit,
2092 log_root_tree->node->start);
2093 btrfs_set_super_log_root_level(&root->fs_info->super_for_commit,
2094 btrfs_header_level(log_root_tree->node));
2096 log_root_tree->log_batch = 0;
2097 log_root_tree->log_transid++;
2100 mutex_unlock(&log_root_tree->log_mutex);
2103 * nobody else is going to jump in and write the the ctree
2104 * super here because the log_commit atomic below is protecting
2105 * us. We must be called with a transaction handle pinning
2106 * the running transaction open, so a full commit can't hop
2107 * in and cause problems either.
2109 write_ctree_super(trans, root->fs_info->tree_root, 2);
2113 atomic_set(&log_root_tree->log_commit[index2], 0);
2115 if (waitqueue_active(&log_root_tree->log_commit_wait[index2]))
2116 wake_up(&log_root_tree->log_commit_wait[index2]);
2118 atomic_set(&root->log_commit[index1], 0);
2120 if (waitqueue_active(&root->log_commit_wait[index1]))
2121 wake_up(&root->log_commit_wait[index1]);
2126 * free all the extents used by the tree log. This should be called
2127 * at commit time of the full transaction
2129 int btrfs_free_log(struct btrfs_trans_handle *trans, struct btrfs_root *root)
2132 struct btrfs_root *log;
2136 struct walk_control wc = {
2138 .process_func = process_one_buffer
2141 if (!root->log_root || root->fs_info->log_root_recovering)
2144 log = root->log_root;
2145 ret = walk_log_tree(trans, log, &wc);
2149 ret = find_first_extent_bit(&log->dirty_log_pages,
2150 0, &start, &end, EXTENT_DIRTY);
2154 clear_extent_dirty(&log->dirty_log_pages,
2155 start, end, GFP_NOFS);
2158 if (log->log_transid > 0) {
2159 ret = btrfs_del_root(trans, root->fs_info->log_root_tree,
2163 root->log_root = NULL;
2164 free_extent_buffer(log->node);
2170 * If both a file and directory are logged, and unlinks or renames are
2171 * mixed in, we have a few interesting corners:
2173 * create file X in dir Y
2174 * link file X to X.link in dir Y
2176 * unlink file X but leave X.link
2179 * After a crash we would expect only X.link to exist. But file X
2180 * didn't get fsync'd again so the log has back refs for X and X.link.
2182 * We solve this by removing directory entries and inode backrefs from the
2183 * log when a file that was logged in the current transaction is
2184 * unlinked. Any later fsync will include the updated log entries, and
2185 * we'll be able to reconstruct the proper directory items from backrefs.
2187 * This optimizations allows us to avoid relogging the entire inode
2188 * or the entire directory.
2190 int btrfs_del_dir_entries_in_log(struct btrfs_trans_handle *trans,
2191 struct btrfs_root *root,
2192 const char *name, int name_len,
2193 struct inode *dir, u64 index)
2195 struct btrfs_root *log;
2196 struct btrfs_dir_item *di;
2197 struct btrfs_path *path;
2201 if (BTRFS_I(dir)->logged_trans < trans->transid)
2204 ret = join_running_log_trans(root);
2208 mutex_lock(&BTRFS_I(dir)->log_mutex);
2210 log = root->log_root;
2211 path = btrfs_alloc_path();
2212 di = btrfs_lookup_dir_item(trans, log, path, dir->i_ino,
2213 name, name_len, -1);
2214 if (di && !IS_ERR(di)) {
2215 ret = btrfs_delete_one_dir_name(trans, log, path, di);
2216 bytes_del += name_len;
2219 btrfs_release_path(log, path);
2220 di = btrfs_lookup_dir_index_item(trans, log, path, dir->i_ino,
2221 index, name, name_len, -1);
2222 if (di && !IS_ERR(di)) {
2223 ret = btrfs_delete_one_dir_name(trans, log, path, di);
2224 bytes_del += name_len;
2228 /* update the directory size in the log to reflect the names
2232 struct btrfs_key key;
2234 key.objectid = dir->i_ino;
2236 key.type = BTRFS_INODE_ITEM_KEY;
2237 btrfs_release_path(log, path);
2239 ret = btrfs_search_slot(trans, log, &key, path, 0, 1);
2241 struct btrfs_inode_item *item;
2244 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2245 struct btrfs_inode_item);
2246 i_size = btrfs_inode_size(path->nodes[0], item);
2247 if (i_size > bytes_del)
2248 i_size -= bytes_del;
2251 btrfs_set_inode_size(path->nodes[0], item, i_size);
2252 btrfs_mark_buffer_dirty(path->nodes[0]);
2255 btrfs_release_path(log, path);
2258 btrfs_free_path(path);
2259 mutex_unlock(&BTRFS_I(dir)->log_mutex);
2260 btrfs_end_log_trans(root);
2265 /* see comments for btrfs_del_dir_entries_in_log */
2266 int btrfs_del_inode_ref_in_log(struct btrfs_trans_handle *trans,
2267 struct btrfs_root *root,
2268 const char *name, int name_len,
2269 struct inode *inode, u64 dirid)
2271 struct btrfs_root *log;
2275 if (BTRFS_I(inode)->logged_trans < trans->transid)
2278 ret = join_running_log_trans(root);
2281 log = root->log_root;
2282 mutex_lock(&BTRFS_I(inode)->log_mutex);
2284 ret = btrfs_del_inode_ref(trans, log, name, name_len, inode->i_ino,
2286 mutex_unlock(&BTRFS_I(inode)->log_mutex);
2287 btrfs_end_log_trans(root);
2293 * creates a range item in the log for 'dirid'. first_offset and
2294 * last_offset tell us which parts of the key space the log should
2295 * be considered authoritative for.
2297 static noinline int insert_dir_log_key(struct btrfs_trans_handle *trans,
2298 struct btrfs_root *log,
2299 struct btrfs_path *path,
2300 int key_type, u64 dirid,
2301 u64 first_offset, u64 last_offset)
2304 struct btrfs_key key;
2305 struct btrfs_dir_log_item *item;
2307 key.objectid = dirid;
2308 key.offset = first_offset;
2309 if (key_type == BTRFS_DIR_ITEM_KEY)
2310 key.type = BTRFS_DIR_LOG_ITEM_KEY;
2312 key.type = BTRFS_DIR_LOG_INDEX_KEY;
2313 ret = btrfs_insert_empty_item(trans, log, path, &key, sizeof(*item));
2316 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2317 struct btrfs_dir_log_item);
2318 btrfs_set_dir_log_end(path->nodes[0], item, last_offset);
2319 btrfs_mark_buffer_dirty(path->nodes[0]);
2320 btrfs_release_path(log, path);
2325 * log all the items included in the current transaction for a given
2326 * directory. This also creates the range items in the log tree required
2327 * to replay anything deleted before the fsync
2329 static noinline int log_dir_items(struct btrfs_trans_handle *trans,
2330 struct btrfs_root *root, struct inode *inode,
2331 struct btrfs_path *path,
2332 struct btrfs_path *dst_path, int key_type,
2333 u64 min_offset, u64 *last_offset_ret)
2335 struct btrfs_key min_key;
2336 struct btrfs_key max_key;
2337 struct btrfs_root *log = root->log_root;
2338 struct extent_buffer *src;
2342 u64 first_offset = min_offset;
2343 u64 last_offset = (u64)-1;
2345 log = root->log_root;
2346 max_key.objectid = inode->i_ino;
2347 max_key.offset = (u64)-1;
2348 max_key.type = key_type;
2350 min_key.objectid = inode->i_ino;
2351 min_key.type = key_type;
2352 min_key.offset = min_offset;
2354 path->keep_locks = 1;
2356 ret = btrfs_search_forward(root, &min_key, &max_key,
2357 path, 0, trans->transid);
2360 * we didn't find anything from this transaction, see if there
2361 * is anything at all
2363 if (ret != 0 || min_key.objectid != inode->i_ino ||
2364 min_key.type != key_type) {
2365 min_key.objectid = inode->i_ino;
2366 min_key.type = key_type;
2367 min_key.offset = (u64)-1;
2368 btrfs_release_path(root, path);
2369 ret = btrfs_search_slot(NULL, root, &min_key, path, 0, 0);
2371 btrfs_release_path(root, path);
2374 ret = btrfs_previous_item(root, path, inode->i_ino, key_type);
2376 /* if ret == 0 there are items for this type,
2377 * create a range to tell us the last key of this type.
2378 * otherwise, there are no items in this directory after
2379 * *min_offset, and we create a range to indicate that.
2382 struct btrfs_key tmp;
2383 btrfs_item_key_to_cpu(path->nodes[0], &tmp,
2385 if (key_type == tmp.type)
2386 first_offset = max(min_offset, tmp.offset) + 1;
2391 /* go backward to find any previous key */
2392 ret = btrfs_previous_item(root, path, inode->i_ino, key_type);
2394 struct btrfs_key tmp;
2395 btrfs_item_key_to_cpu(path->nodes[0], &tmp, path->slots[0]);
2396 if (key_type == tmp.type) {
2397 first_offset = tmp.offset;
2398 ret = overwrite_item(trans, log, dst_path,
2399 path->nodes[0], path->slots[0],
2403 btrfs_release_path(root, path);
2405 /* find the first key from this transaction again */
2406 ret = btrfs_search_slot(NULL, root, &min_key, path, 0, 0);
2413 * we have a block from this transaction, log every item in it
2414 * from our directory
2417 struct btrfs_key tmp;
2418 src = path->nodes[0];
2419 nritems = btrfs_header_nritems(src);
2420 for (i = path->slots[0]; i < nritems; i++) {
2421 btrfs_item_key_to_cpu(src, &min_key, i);
2423 if (min_key.objectid != inode->i_ino ||
2424 min_key.type != key_type)
2426 ret = overwrite_item(trans, log, dst_path, src, i,
2430 path->slots[0] = nritems;
2433 * look ahead to the next item and see if it is also
2434 * from this directory and from this transaction
2436 ret = btrfs_next_leaf(root, path);
2438 last_offset = (u64)-1;
2441 btrfs_item_key_to_cpu(path->nodes[0], &tmp, path->slots[0]);
2442 if (tmp.objectid != inode->i_ino || tmp.type != key_type) {
2443 last_offset = (u64)-1;
2446 if (btrfs_header_generation(path->nodes[0]) != trans->transid) {
2447 ret = overwrite_item(trans, log, dst_path,
2448 path->nodes[0], path->slots[0],
2452 last_offset = tmp.offset;
2457 *last_offset_ret = last_offset;
2458 btrfs_release_path(root, path);
2459 btrfs_release_path(log, dst_path);
2461 /* insert the log range keys to indicate where the log is valid */
2462 ret = insert_dir_log_key(trans, log, path, key_type, inode->i_ino,
2463 first_offset, last_offset);
2469 * logging directories is very similar to logging inodes, We find all the items
2470 * from the current transaction and write them to the log.
2472 * The recovery code scans the directory in the subvolume, and if it finds a
2473 * key in the range logged that is not present in the log tree, then it means
2474 * that dir entry was unlinked during the transaction.
2476 * In order for that scan to work, we must include one key smaller than
2477 * the smallest logged by this transaction and one key larger than the largest
2478 * key logged by this transaction.
2480 static noinline int log_directory_changes(struct btrfs_trans_handle *trans,
2481 struct btrfs_root *root, struct inode *inode,
2482 struct btrfs_path *path,
2483 struct btrfs_path *dst_path)
2488 int key_type = BTRFS_DIR_ITEM_KEY;
2494 ret = log_dir_items(trans, root, inode, path,
2495 dst_path, key_type, min_key,
2498 if (max_key == (u64)-1)
2500 min_key = max_key + 1;
2503 if (key_type == BTRFS_DIR_ITEM_KEY) {
2504 key_type = BTRFS_DIR_INDEX_KEY;
2511 * a helper function to drop items from the log before we relog an
2512 * inode. max_key_type indicates the highest item type to remove.
2513 * This cannot be run for file data extents because it does not
2514 * free the extents they point to.
2516 static int drop_objectid_items(struct btrfs_trans_handle *trans,
2517 struct btrfs_root *log,
2518 struct btrfs_path *path,
2519 u64 objectid, int max_key_type)
2522 struct btrfs_key key;
2523 struct btrfs_key found_key;
2525 key.objectid = objectid;
2526 key.type = max_key_type;
2527 key.offset = (u64)-1;
2530 ret = btrfs_search_slot(trans, log, &key, path, -1, 1);
2535 if (path->slots[0] == 0)
2539 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
2542 if (found_key.objectid != objectid)
2545 ret = btrfs_del_item(trans, log, path);
2547 btrfs_release_path(log, path);
2549 btrfs_release_path(log, path);
2553 static noinline int copy_items(struct btrfs_trans_handle *trans,
2554 struct btrfs_root *log,
2555 struct btrfs_path *dst_path,
2556 struct extent_buffer *src,
2557 int start_slot, int nr, int inode_only)
2559 unsigned long src_offset;
2560 unsigned long dst_offset;
2561 struct btrfs_file_extent_item *extent;
2562 struct btrfs_inode_item *inode_item;
2564 struct btrfs_key *ins_keys;
2568 struct list_head ordered_sums;
2570 INIT_LIST_HEAD(&ordered_sums);
2572 ins_data = kmalloc(nr * sizeof(struct btrfs_key) +
2573 nr * sizeof(u32), GFP_NOFS);
2574 ins_sizes = (u32 *)ins_data;
2575 ins_keys = (struct btrfs_key *)(ins_data + nr * sizeof(u32));
2577 for (i = 0; i < nr; i++) {
2578 ins_sizes[i] = btrfs_item_size_nr(src, i + start_slot);
2579 btrfs_item_key_to_cpu(src, ins_keys + i, i + start_slot);
2581 ret = btrfs_insert_empty_items(trans, log, dst_path,
2582 ins_keys, ins_sizes, nr);
2585 for (i = 0; i < nr; i++) {
2586 dst_offset = btrfs_item_ptr_offset(dst_path->nodes[0],
2587 dst_path->slots[0]);
2589 src_offset = btrfs_item_ptr_offset(src, start_slot + i);
2591 copy_extent_buffer(dst_path->nodes[0], src, dst_offset,
2592 src_offset, ins_sizes[i]);
2594 if (inode_only == LOG_INODE_EXISTS &&
2595 ins_keys[i].type == BTRFS_INODE_ITEM_KEY) {
2596 inode_item = btrfs_item_ptr(dst_path->nodes[0],
2598 struct btrfs_inode_item);
2599 btrfs_set_inode_size(dst_path->nodes[0], inode_item, 0);
2601 /* set the generation to zero so the recover code
2602 * can tell the difference between an logging
2603 * just to say 'this inode exists' and a logging
2604 * to say 'update this inode with these values'
2606 btrfs_set_inode_generation(dst_path->nodes[0],
2609 /* take a reference on file data extents so that truncates
2610 * or deletes of this inode don't have to relog the inode
2613 if (btrfs_key_type(ins_keys + i) == BTRFS_EXTENT_DATA_KEY) {
2615 extent = btrfs_item_ptr(src, start_slot + i,
2616 struct btrfs_file_extent_item);
2618 found_type = btrfs_file_extent_type(src, extent);
2619 if (found_type == BTRFS_FILE_EXTENT_REG ||
2620 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
2621 u64 ds = btrfs_file_extent_disk_bytenr(src,
2623 u64 dl = btrfs_file_extent_disk_num_bytes(src,
2625 u64 cs = btrfs_file_extent_offset(src, extent);
2626 u64 cl = btrfs_file_extent_num_bytes(src,
2628 if (btrfs_file_extent_compression(src,
2633 /* ds == 0 is a hole */
2635 ret = btrfs_inc_extent_ref(trans, log,
2637 dst_path->nodes[0]->start,
2638 BTRFS_TREE_LOG_OBJECTID,
2640 ins_keys[i].objectid);
2642 ret = btrfs_lookup_csums_range(
2643 log->fs_info->csum_root,
2644 ds + cs, ds + cs + cl - 1,
2650 dst_path->slots[0]++;
2653 btrfs_mark_buffer_dirty(dst_path->nodes[0]);
2654 btrfs_release_path(log, dst_path);
2658 * we have to do this after the loop above to avoid changing the
2659 * log tree while trying to change the log tree.
2661 while (!list_empty(&ordered_sums)) {
2662 struct btrfs_ordered_sum *sums = list_entry(ordered_sums.next,
2663 struct btrfs_ordered_sum,
2665 ret = btrfs_csum_file_blocks(trans, log, sums);
2667 list_del(&sums->list);
2673 /* log a single inode in the tree log.
2674 * At least one parent directory for this inode must exist in the tree
2675 * or be logged already.
2677 * Any items from this inode changed by the current transaction are copied
2678 * to the log tree. An extra reference is taken on any extents in this
2679 * file, allowing us to avoid a whole pile of corner cases around logging
2680 * blocks that have been removed from the tree.
2682 * See LOG_INODE_ALL and related defines for a description of what inode_only
2685 * This handles both files and directories.
2687 static int btrfs_log_inode(struct btrfs_trans_handle *trans,
2688 struct btrfs_root *root, struct inode *inode,
2691 struct btrfs_path *path;
2692 struct btrfs_path *dst_path;
2693 struct btrfs_key min_key;
2694 struct btrfs_key max_key;
2695 struct btrfs_root *log = root->log_root;
2696 struct extent_buffer *src = NULL;
2700 int ins_start_slot = 0;
2703 log = root->log_root;
2705 path = btrfs_alloc_path();
2706 dst_path = btrfs_alloc_path();
2708 min_key.objectid = inode->i_ino;
2709 min_key.type = BTRFS_INODE_ITEM_KEY;
2712 max_key.objectid = inode->i_ino;
2714 /* today the code can only do partial logging of directories */
2715 if (!S_ISDIR(inode->i_mode))
2716 inode_only = LOG_INODE_ALL;
2718 if (inode_only == LOG_INODE_EXISTS || S_ISDIR(inode->i_mode))
2719 max_key.type = BTRFS_XATTR_ITEM_KEY;
2721 max_key.type = (u8)-1;
2722 max_key.offset = (u64)-1;
2724 mutex_lock(&BTRFS_I(inode)->log_mutex);
2727 * a brute force approach to making sure we get the most uptodate
2728 * copies of everything.
2730 if (S_ISDIR(inode->i_mode)) {
2731 int max_key_type = BTRFS_DIR_LOG_INDEX_KEY;
2733 if (inode_only == LOG_INODE_EXISTS)
2734 max_key_type = BTRFS_XATTR_ITEM_KEY;
2735 ret = drop_objectid_items(trans, log, path,
2736 inode->i_ino, max_key_type);
2738 ret = btrfs_truncate_inode_items(trans, log, inode, 0, 0);
2741 path->keep_locks = 1;
2745 ret = btrfs_search_forward(root, &min_key, &max_key,
2746 path, 0, trans->transid);
2750 /* note, ins_nr might be > 0 here, cleanup outside the loop */
2751 if (min_key.objectid != inode->i_ino)
2753 if (min_key.type > max_key.type)
2756 src = path->nodes[0];
2757 size = btrfs_item_size_nr(src, path->slots[0]);
2758 if (ins_nr && ins_start_slot + ins_nr == path->slots[0]) {
2761 } else if (!ins_nr) {
2762 ins_start_slot = path->slots[0];
2767 ret = copy_items(trans, log, dst_path, src, ins_start_slot,
2768 ins_nr, inode_only);
2771 ins_start_slot = path->slots[0];
2774 nritems = btrfs_header_nritems(path->nodes[0]);
2776 if (path->slots[0] < nritems) {
2777 btrfs_item_key_to_cpu(path->nodes[0], &min_key,
2782 ret = copy_items(trans, log, dst_path, src,
2784 ins_nr, inode_only);
2788 btrfs_release_path(root, path);
2790 if (min_key.offset < (u64)-1)
2792 else if (min_key.type < (u8)-1)
2794 else if (min_key.objectid < (u64)-1)
2800 ret = copy_items(trans, log, dst_path, src,
2802 ins_nr, inode_only);
2807 if (inode_only == LOG_INODE_ALL && S_ISDIR(inode->i_mode)) {
2808 btrfs_release_path(root, path);
2809 btrfs_release_path(log, dst_path);
2810 ret = log_directory_changes(trans, root, inode, path, dst_path);
2813 BTRFS_I(inode)->logged_trans = trans->transid;
2814 mutex_unlock(&BTRFS_I(inode)->log_mutex);
2816 btrfs_free_path(path);
2817 btrfs_free_path(dst_path);
2822 * follow the dentry parent pointers up the chain and see if any
2823 * of the directories in it require a full commit before they can
2824 * be logged. Returns zero if nothing special needs to be done or 1 if
2825 * a full commit is required.
2827 static noinline int check_parent_dirs_for_sync(struct btrfs_trans_handle *trans,
2828 struct inode *inode,
2829 struct dentry *parent,
2830 struct super_block *sb,
2834 struct btrfs_root *root;
2837 * for regular files, if its inode is already on disk, we don't
2838 * have to worry about the parents at all. This is because
2839 * we can use the last_unlink_trans field to record renames
2840 * and other fun in this file.
2842 if (S_ISREG(inode->i_mode) &&
2843 BTRFS_I(inode)->generation <= last_committed &&
2844 BTRFS_I(inode)->last_unlink_trans <= last_committed)
2847 if (!S_ISDIR(inode->i_mode)) {
2848 if (!parent || !parent->d_inode || sb != parent->d_inode->i_sb)
2850 inode = parent->d_inode;
2854 BTRFS_I(inode)->logged_trans = trans->transid;
2857 if (BTRFS_I(inode)->last_unlink_trans > last_committed) {
2858 root = BTRFS_I(inode)->root;
2861 * make sure any commits to the log are forced
2862 * to be full commits
2864 root->fs_info->last_trans_log_full_commit =
2870 if (!parent || !parent->d_inode || sb != parent->d_inode->i_sb)
2873 if (parent == sb->s_root)
2876 parent = parent->d_parent;
2877 inode = parent->d_inode;
2885 * helper function around btrfs_log_inode to make sure newly created
2886 * parent directories also end up in the log. A minimal inode and backref
2887 * only logging is done of any parent directories that are older than
2888 * the last committed transaction
2890 int btrfs_log_inode_parent(struct btrfs_trans_handle *trans,
2891 struct btrfs_root *root, struct inode *inode,
2892 struct dentry *parent, int exists_only)
2894 int inode_only = exists_only ? LOG_INODE_EXISTS : LOG_INODE_ALL;
2895 struct super_block *sb;
2897 u64 last_committed = root->fs_info->last_trans_committed;
2901 if (btrfs_test_opt(root, NOTREELOG)) {
2906 if (root->fs_info->last_trans_log_full_commit >
2907 root->fs_info->last_trans_committed) {
2912 ret = check_parent_dirs_for_sync(trans, inode, parent,
2913 sb, last_committed);
2917 start_log_trans(trans, root);
2919 ret = btrfs_log_inode(trans, root, inode, inode_only);
2923 * for regular files, if its inode is already on disk, we don't
2924 * have to worry about the parents at all. This is because
2925 * we can use the last_unlink_trans field to record renames
2926 * and other fun in this file.
2928 if (S_ISREG(inode->i_mode) &&
2929 BTRFS_I(inode)->generation <= last_committed &&
2930 BTRFS_I(inode)->last_unlink_trans <= last_committed)
2933 inode_only = LOG_INODE_EXISTS;
2935 if (!parent || !parent->d_inode || sb != parent->d_inode->i_sb)
2938 inode = parent->d_inode;
2939 if (BTRFS_I(inode)->generation >
2940 root->fs_info->last_trans_committed) {
2941 ret = btrfs_log_inode(trans, root, inode, inode_only);
2944 if (parent == sb->s_root)
2947 parent = parent->d_parent;
2951 btrfs_end_log_trans(root);
2957 * it is not safe to log dentry if the chunk root has added new
2958 * chunks. This returns 0 if the dentry was logged, and 1 otherwise.
2959 * If this returns 1, you must commit the transaction to safely get your
2962 int btrfs_log_dentry_safe(struct btrfs_trans_handle *trans,
2963 struct btrfs_root *root, struct dentry *dentry)
2965 return btrfs_log_inode_parent(trans, root, dentry->d_inode,
2966 dentry->d_parent, 0);
2970 * should be called during mount to recover any replay any log trees
2973 int btrfs_recover_log_trees(struct btrfs_root *log_root_tree)
2976 struct btrfs_path *path;
2977 struct btrfs_trans_handle *trans;
2978 struct btrfs_key key;
2979 struct btrfs_key found_key;
2980 struct btrfs_key tmp_key;
2981 struct btrfs_root *log;
2982 struct btrfs_fs_info *fs_info = log_root_tree->fs_info;
2984 struct walk_control wc = {
2985 .process_func = process_one_buffer,
2989 fs_info->log_root_recovering = 1;
2990 path = btrfs_alloc_path();
2993 trans = btrfs_start_transaction(fs_info->tree_root, 1);
2998 walk_log_tree(trans, log_root_tree, &wc);
3001 key.objectid = BTRFS_TREE_LOG_OBJECTID;
3002 key.offset = (u64)-1;
3003 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
3006 ret = btrfs_search_slot(NULL, log_root_tree, &key, path, 0, 0);
3010 if (path->slots[0] == 0)
3014 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
3016 btrfs_release_path(log_root_tree, path);
3017 if (found_key.objectid != BTRFS_TREE_LOG_OBJECTID)
3020 log = btrfs_read_fs_root_no_radix(log_root_tree,
3025 tmp_key.objectid = found_key.offset;
3026 tmp_key.type = BTRFS_ROOT_ITEM_KEY;
3027 tmp_key.offset = (u64)-1;
3029 wc.replay_dest = btrfs_read_fs_root_no_name(fs_info, &tmp_key);
3030 BUG_ON(!wc.replay_dest);
3032 wc.replay_dest->log_root = log;
3033 mutex_lock(&fs_info->trans_mutex);
3034 btrfs_record_root_in_trans(wc.replay_dest);
3035 mutex_unlock(&fs_info->trans_mutex);
3036 ret = walk_log_tree(trans, log, &wc);
3039 if (wc.stage == LOG_WALK_REPLAY_ALL) {
3040 ret = fixup_inode_link_counts(trans, wc.replay_dest,
3044 ret = btrfs_find_highest_inode(wc.replay_dest, &highest_inode);
3046 wc.replay_dest->highest_inode = highest_inode;
3047 wc.replay_dest->last_inode_alloc = highest_inode;
3050 key.offset = found_key.offset - 1;
3051 wc.replay_dest->log_root = NULL;
3052 free_extent_buffer(log->node);
3055 if (found_key.offset == 0)
3058 btrfs_release_path(log_root_tree, path);
3060 /* step one is to pin it all, step two is to replay just inodes */
3063 wc.process_func = replay_one_buffer;
3064 wc.stage = LOG_WALK_REPLAY_INODES;
3067 /* step three is to replay everything */
3068 if (wc.stage < LOG_WALK_REPLAY_ALL) {
3073 btrfs_free_path(path);
3075 free_extent_buffer(log_root_tree->node);
3076 log_root_tree->log_root = NULL;
3077 fs_info->log_root_recovering = 0;
3079 /* step 4: commit the transaction, which also unpins the blocks */
3080 btrfs_commit_transaction(trans, fs_info->tree_root);
3082 kfree(log_root_tree);
3087 * there are some corner cases where we want to force a full
3088 * commit instead of allowing a directory to be logged.
3090 * They revolve around files there were unlinked from the directory, and
3091 * this function updates the parent directory so that a full commit is
3092 * properly done if it is fsync'd later after the unlinks are done.
3094 void btrfs_record_unlink_dir(struct btrfs_trans_handle *trans,
3095 struct inode *dir, struct inode *inode,
3099 * when we're logging a file, if it hasn't been renamed
3100 * or unlinked, and its inode is fully committed on disk,
3101 * we don't have to worry about walking up the directory chain
3102 * to log its parents.
3104 * So, we use the last_unlink_trans field to put this transid
3105 * into the file. When the file is logged we check it and
3106 * don't log the parents if the file is fully on disk.
3108 if (S_ISREG(inode->i_mode))
3109 BTRFS_I(inode)->last_unlink_trans = trans->transid;
3112 * if this directory was already logged any new
3113 * names for this file/dir will get recorded
3116 if (BTRFS_I(dir)->logged_trans == trans->transid)
3120 * if the inode we're about to unlink was logged,
3121 * the log will be properly updated for any new names
3123 if (BTRFS_I(inode)->logged_trans == trans->transid)
3127 * when renaming files across directories, if the directory
3128 * there we're unlinking from gets fsync'd later on, there's
3129 * no way to find the destination directory later and fsync it
3130 * properly. So, we have to be conservative and force commits
3131 * so the new name gets discovered.
3136 /* we can safely do the unlink without any special recording */
3140 BTRFS_I(dir)->last_unlink_trans = trans->transid;
3144 * Call this after adding a new name for a file and it will properly
3145 * update the log to reflect the new name.
3147 * It will return zero if all goes well, and it will return 1 if a
3148 * full transaction commit is required.
3150 int btrfs_log_new_name(struct btrfs_trans_handle *trans,
3151 struct inode *inode, struct inode *old_dir,
3152 struct dentry *parent)
3154 struct btrfs_root * root = BTRFS_I(inode)->root;
3157 * this will force the logging code to walk the dentry chain
3160 if (S_ISREG(inode->i_mode))
3161 BTRFS_I(inode)->last_unlink_trans = trans->transid;
3164 * if this inode hasn't been logged and directory we're renaming it
3165 * from hasn't been logged, we don't need to log it
3167 if (BTRFS_I(inode)->logged_trans <=
3168 root->fs_info->last_trans_committed &&
3169 (!old_dir || BTRFS_I(old_dir)->logged_trans <=
3170 root->fs_info->last_trans_committed))
3173 return btrfs_log_inode_parent(trans, root, inode, parent, 1);