1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (C) 2008 Oracle. All rights reserved.
6 #include <linux/sched.h>
7 #include <linux/slab.h>
8 #include <linux/blkdev.h>
9 #include <linux/list_sort.h>
10 #include <linux/iversion.h>
16 #include "print-tree.h"
18 #include "compression.h"
20 #include "block-group.h"
21 #include "space-info.h"
24 /* magic values for the inode_only field in btrfs_log_inode:
26 * LOG_INODE_ALL means to log everything
27 * LOG_INODE_EXISTS means to log just enough to recreate the inode
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
91 LOG_WALK_REPLAY_INODES,
92 LOG_WALK_REPLAY_DIR_INDEX,
96 static int btrfs_log_inode(struct btrfs_trans_handle *trans,
97 struct btrfs_root *root, struct btrfs_inode *inode,
99 struct btrfs_log_ctx *ctx);
100 static int link_to_fixup_dir(struct btrfs_trans_handle *trans,
101 struct btrfs_root *root,
102 struct btrfs_path *path, u64 objectid);
103 static noinline int replay_dir_deletes(struct btrfs_trans_handle *trans,
104 struct btrfs_root *root,
105 struct btrfs_root *log,
106 struct btrfs_path *path,
107 u64 dirid, int del_all);
108 static void wait_log_commit(struct btrfs_root *root, int transid);
111 * tree logging is a special write ahead log used to make sure that
112 * fsyncs and O_SYNCs can happen without doing full tree commits.
114 * Full tree commits are expensive because they require commonly
115 * modified blocks to be recowed, creating many dirty pages in the
116 * extent tree an 4x-6x higher write load than ext3.
118 * Instead of doing a tree commit on every fsync, we use the
119 * key ranges and transaction ids to find items for a given file or directory
120 * that have changed in this transaction. Those items are copied into
121 * a special tree (one per subvolume root), that tree is written to disk
122 * and then the fsync is considered complete.
124 * After a crash, items are copied out of the log-tree back into the
125 * subvolume tree. Any file data extents found are recorded in the extent
126 * allocation tree, and the log-tree freed.
128 * The log tree is read three times, once to pin down all the extents it is
129 * using in ram and once, once to create all the inodes logged in the tree
130 * and once to do all the other items.
134 * start a sub transaction and setup the log tree
135 * this increments the log tree writer count to make the people
136 * syncing the tree wait for us to finish
138 static int start_log_trans(struct btrfs_trans_handle *trans,
139 struct btrfs_root *root,
140 struct btrfs_log_ctx *ctx)
142 struct btrfs_fs_info *fs_info = root->fs_info;
143 struct btrfs_root *tree_root = fs_info->tree_root;
144 const bool zoned = btrfs_is_zoned(fs_info);
146 bool created = false;
149 * First check if the log root tree was already created. If not, create
150 * it before locking the root's log_mutex, just to keep lockdep happy.
152 if (!test_bit(BTRFS_ROOT_HAS_LOG_TREE, &tree_root->state)) {
153 mutex_lock(&tree_root->log_mutex);
154 if (!fs_info->log_root_tree) {
155 ret = btrfs_init_log_root_tree(trans, fs_info);
157 set_bit(BTRFS_ROOT_HAS_LOG_TREE, &tree_root->state);
161 mutex_unlock(&tree_root->log_mutex);
166 mutex_lock(&root->log_mutex);
169 if (root->log_root) {
170 int index = (root->log_transid + 1) % 2;
172 if (btrfs_need_log_full_commit(trans)) {
177 if (zoned && atomic_read(&root->log_commit[index])) {
178 wait_log_commit(root, root->log_transid - 1);
182 if (!root->log_start_pid) {
183 clear_bit(BTRFS_ROOT_MULTI_LOG_TASKS, &root->state);
184 root->log_start_pid = current->pid;
185 } else if (root->log_start_pid != current->pid) {
186 set_bit(BTRFS_ROOT_MULTI_LOG_TASKS, &root->state);
190 * This means fs_info->log_root_tree was already created
191 * for some other FS trees. Do the full commit not to mix
192 * nodes from multiple log transactions to do sequential
195 if (zoned && !created) {
200 ret = btrfs_add_log_tree(trans, root);
204 set_bit(BTRFS_ROOT_HAS_LOG_TREE, &root->state);
205 clear_bit(BTRFS_ROOT_MULTI_LOG_TASKS, &root->state);
206 root->log_start_pid = current->pid;
209 atomic_inc(&root->log_writers);
210 if (ctx && !ctx->logging_new_name) {
211 int index = root->log_transid % 2;
212 list_add_tail(&ctx->list, &root->log_ctxs[index]);
213 ctx->log_transid = root->log_transid;
217 mutex_unlock(&root->log_mutex);
222 * returns 0 if there was a log transaction running and we were able
223 * to join, or returns -ENOENT if there were not transactions
226 static int join_running_log_trans(struct btrfs_root *root)
228 const bool zoned = btrfs_is_zoned(root->fs_info);
231 if (!test_bit(BTRFS_ROOT_HAS_LOG_TREE, &root->state))
234 mutex_lock(&root->log_mutex);
236 if (root->log_root) {
237 int index = (root->log_transid + 1) % 2;
240 if (zoned && atomic_read(&root->log_commit[index])) {
241 wait_log_commit(root, root->log_transid - 1);
244 atomic_inc(&root->log_writers);
246 mutex_unlock(&root->log_mutex);
251 * This either makes the current running log transaction wait
252 * until you call btrfs_end_log_trans() or it makes any future
253 * log transactions wait until you call btrfs_end_log_trans()
255 void btrfs_pin_log_trans(struct btrfs_root *root)
257 atomic_inc(&root->log_writers);
261 * indicate we're done making changes to the log tree
262 * and wake up anyone waiting to do a sync
264 void btrfs_end_log_trans(struct btrfs_root *root)
266 if (atomic_dec_and_test(&root->log_writers)) {
267 /* atomic_dec_and_test implies a barrier */
268 cond_wake_up_nomb(&root->log_writer_wait);
272 static int btrfs_write_tree_block(struct extent_buffer *buf)
274 return filemap_fdatawrite_range(buf->pages[0]->mapping, buf->start,
275 buf->start + buf->len - 1);
278 static void btrfs_wait_tree_block_writeback(struct extent_buffer *buf)
280 filemap_fdatawait_range(buf->pages[0]->mapping,
281 buf->start, buf->start + buf->len - 1);
285 * the walk control struct is used to pass state down the chain when
286 * processing the log tree. The stage field tells us which part
287 * of the log tree processing we are currently doing. The others
288 * are state fields used for that specific part
290 struct walk_control {
291 /* should we free the extent on disk when done? This is used
292 * at transaction commit time while freeing a log tree
296 /* should we write out the extent buffer? This is used
297 * while flushing the log tree to disk during a sync
301 /* should we wait for the extent buffer io to finish? Also used
302 * while flushing the log tree to disk for a sync
306 /* pin only walk, we record which extents on disk belong to the
311 /* what stage of the replay code we're currently in */
315 * Ignore any items from the inode currently being processed. Needs
316 * to be set every time we find a BTRFS_INODE_ITEM_KEY and we are in
317 * the LOG_WALK_REPLAY_INODES stage.
319 bool ignore_cur_inode;
321 /* the root we are currently replaying */
322 struct btrfs_root *replay_dest;
324 /* the trans handle for the current replay */
325 struct btrfs_trans_handle *trans;
327 /* the function that gets used to process blocks we find in the
328 * tree. Note the extent_buffer might not be up to date when it is
329 * passed in, and it must be checked or read if you need the data
332 int (*process_func)(struct btrfs_root *log, struct extent_buffer *eb,
333 struct walk_control *wc, u64 gen, int level);
337 * process_func used to pin down extents, write them or wait on them
339 static int process_one_buffer(struct btrfs_root *log,
340 struct extent_buffer *eb,
341 struct walk_control *wc, u64 gen, int level)
343 struct btrfs_fs_info *fs_info = log->fs_info;
347 * If this fs is mixed then we need to be able to process the leaves to
348 * pin down any logged extents, so we have to read the block.
350 if (btrfs_fs_incompat(fs_info, MIXED_GROUPS)) {
351 ret = btrfs_read_buffer(eb, gen, level, NULL);
357 ret = btrfs_pin_extent_for_log_replay(wc->trans, eb->start,
360 if (!ret && btrfs_buffer_uptodate(eb, gen, 0)) {
361 if (wc->pin && btrfs_header_level(eb) == 0)
362 ret = btrfs_exclude_logged_extents(eb);
364 btrfs_write_tree_block(eb);
366 btrfs_wait_tree_block_writeback(eb);
372 * Item overwrite used by replay and tree logging. eb, slot and key all refer
373 * to the src data we are copying out.
375 * root is the tree we are copying into, and path is a scratch
376 * path for use in this function (it should be released on entry and
377 * will be released on exit).
379 * If the key is already in the destination tree the existing item is
380 * overwritten. If the existing item isn't big enough, it is extended.
381 * If it is too large, it is truncated.
383 * If the key isn't in the destination yet, a new item is inserted.
385 static noinline int overwrite_item(struct btrfs_trans_handle *trans,
386 struct btrfs_root *root,
387 struct btrfs_path *path,
388 struct extent_buffer *eb, int slot,
389 struct btrfs_key *key)
393 u64 saved_i_size = 0;
394 int save_old_i_size = 0;
395 unsigned long src_ptr;
396 unsigned long dst_ptr;
397 int overwrite_root = 0;
398 bool inode_item = key->type == BTRFS_INODE_ITEM_KEY;
400 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID)
403 item_size = btrfs_item_size_nr(eb, slot);
404 src_ptr = btrfs_item_ptr_offset(eb, slot);
406 /* look for the key in the destination tree */
407 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
414 u32 dst_size = btrfs_item_size_nr(path->nodes[0],
416 if (dst_size != item_size)
419 if (item_size == 0) {
420 btrfs_release_path(path);
423 dst_copy = kmalloc(item_size, GFP_NOFS);
424 src_copy = kmalloc(item_size, GFP_NOFS);
425 if (!dst_copy || !src_copy) {
426 btrfs_release_path(path);
432 read_extent_buffer(eb, src_copy, src_ptr, item_size);
434 dst_ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
435 read_extent_buffer(path->nodes[0], dst_copy, dst_ptr,
437 ret = memcmp(dst_copy, src_copy, item_size);
442 * they have the same contents, just return, this saves
443 * us from cowing blocks in the destination tree and doing
444 * extra writes that may not have been done by a previous
448 btrfs_release_path(path);
453 * We need to load the old nbytes into the inode so when we
454 * replay the extents we've logged we get the right nbytes.
457 struct btrfs_inode_item *item;
461 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
462 struct btrfs_inode_item);
463 nbytes = btrfs_inode_nbytes(path->nodes[0], item);
464 item = btrfs_item_ptr(eb, slot,
465 struct btrfs_inode_item);
466 btrfs_set_inode_nbytes(eb, item, nbytes);
469 * If this is a directory we need to reset the i_size to
470 * 0 so that we can set it up properly when replaying
471 * the rest of the items in this log.
473 mode = btrfs_inode_mode(eb, item);
475 btrfs_set_inode_size(eb, item, 0);
477 } else if (inode_item) {
478 struct btrfs_inode_item *item;
482 * New inode, set nbytes to 0 so that the nbytes comes out
483 * properly when we replay the extents.
485 item = btrfs_item_ptr(eb, slot, struct btrfs_inode_item);
486 btrfs_set_inode_nbytes(eb, item, 0);
489 * If this is a directory we need to reset the i_size to 0 so
490 * that we can set it up properly when replaying the rest of
491 * the items in this log.
493 mode = btrfs_inode_mode(eb, item);
495 btrfs_set_inode_size(eb, item, 0);
498 btrfs_release_path(path);
499 /* try to insert the key into the destination tree */
500 path->skip_release_on_error = 1;
501 ret = btrfs_insert_empty_item(trans, root, path,
503 path->skip_release_on_error = 0;
505 /* make sure any existing item is the correct size */
506 if (ret == -EEXIST || ret == -EOVERFLOW) {
508 found_size = btrfs_item_size_nr(path->nodes[0],
510 if (found_size > item_size)
511 btrfs_truncate_item(path, item_size, 1);
512 else if (found_size < item_size)
513 btrfs_extend_item(path, item_size - found_size);
517 dst_ptr = btrfs_item_ptr_offset(path->nodes[0],
520 /* don't overwrite an existing inode if the generation number
521 * was logged as zero. This is done when the tree logging code
522 * is just logging an inode to make sure it exists after recovery.
524 * Also, don't overwrite i_size on directories during replay.
525 * log replay inserts and removes directory items based on the
526 * state of the tree found in the subvolume, and i_size is modified
529 if (key->type == BTRFS_INODE_ITEM_KEY && ret == -EEXIST) {
530 struct btrfs_inode_item *src_item;
531 struct btrfs_inode_item *dst_item;
533 src_item = (struct btrfs_inode_item *)src_ptr;
534 dst_item = (struct btrfs_inode_item *)dst_ptr;
536 if (btrfs_inode_generation(eb, src_item) == 0) {
537 struct extent_buffer *dst_eb = path->nodes[0];
538 const u64 ino_size = btrfs_inode_size(eb, src_item);
541 * For regular files an ino_size == 0 is used only when
542 * logging that an inode exists, as part of a directory
543 * fsync, and the inode wasn't fsynced before. In this
544 * case don't set the size of the inode in the fs/subvol
545 * tree, otherwise we would be throwing valid data away.
547 if (S_ISREG(btrfs_inode_mode(eb, src_item)) &&
548 S_ISREG(btrfs_inode_mode(dst_eb, dst_item)) &&
550 btrfs_set_inode_size(dst_eb, dst_item, ino_size);
554 if (overwrite_root &&
555 S_ISDIR(btrfs_inode_mode(eb, src_item)) &&
556 S_ISDIR(btrfs_inode_mode(path->nodes[0], dst_item))) {
558 saved_i_size = btrfs_inode_size(path->nodes[0],
563 copy_extent_buffer(path->nodes[0], eb, dst_ptr,
566 if (save_old_i_size) {
567 struct btrfs_inode_item *dst_item;
568 dst_item = (struct btrfs_inode_item *)dst_ptr;
569 btrfs_set_inode_size(path->nodes[0], dst_item, saved_i_size);
572 /* make sure the generation is filled in */
573 if (key->type == BTRFS_INODE_ITEM_KEY) {
574 struct btrfs_inode_item *dst_item;
575 dst_item = (struct btrfs_inode_item *)dst_ptr;
576 if (btrfs_inode_generation(path->nodes[0], dst_item) == 0) {
577 btrfs_set_inode_generation(path->nodes[0], dst_item,
582 btrfs_mark_buffer_dirty(path->nodes[0]);
583 btrfs_release_path(path);
588 * simple helper to read an inode off the disk from a given root
589 * This can only be called for subvolume roots and not for the log
591 static noinline struct inode *read_one_inode(struct btrfs_root *root,
596 inode = btrfs_iget(root->fs_info->sb, objectid, root);
602 /* replays a single extent in 'eb' at 'slot' with 'key' into the
603 * subvolume 'root'. path is released on entry and should be released
606 * extents in the log tree have not been allocated out of the extent
607 * tree yet. So, this completes the allocation, taking a reference
608 * as required if the extent already exists or creating a new extent
609 * if it isn't in the extent allocation tree yet.
611 * The extent is inserted into the file, dropping any existing extents
612 * from the file that overlap the new one.
614 static noinline int replay_one_extent(struct btrfs_trans_handle *trans,
615 struct btrfs_root *root,
616 struct btrfs_path *path,
617 struct extent_buffer *eb, int slot,
618 struct btrfs_key *key)
620 struct btrfs_drop_extents_args drop_args = { 0 };
621 struct btrfs_fs_info *fs_info = root->fs_info;
624 u64 start = key->offset;
626 struct btrfs_file_extent_item *item;
627 struct inode *inode = NULL;
631 item = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
632 found_type = btrfs_file_extent_type(eb, item);
634 if (found_type == BTRFS_FILE_EXTENT_REG ||
635 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
636 nbytes = btrfs_file_extent_num_bytes(eb, item);
637 extent_end = start + nbytes;
640 * We don't add to the inodes nbytes if we are prealloc or a
643 if (btrfs_file_extent_disk_bytenr(eb, item) == 0)
645 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
646 size = btrfs_file_extent_ram_bytes(eb, item);
647 nbytes = btrfs_file_extent_ram_bytes(eb, item);
648 extent_end = ALIGN(start + size,
649 fs_info->sectorsize);
655 inode = read_one_inode(root, key->objectid);
662 * first check to see if we already have this extent in the
663 * file. This must be done before the btrfs_drop_extents run
664 * so we don't try to drop this extent.
666 ret = btrfs_lookup_file_extent(trans, root, path,
667 btrfs_ino(BTRFS_I(inode)), start, 0);
670 (found_type == BTRFS_FILE_EXTENT_REG ||
671 found_type == BTRFS_FILE_EXTENT_PREALLOC)) {
672 struct btrfs_file_extent_item cmp1;
673 struct btrfs_file_extent_item cmp2;
674 struct btrfs_file_extent_item *existing;
675 struct extent_buffer *leaf;
677 leaf = path->nodes[0];
678 existing = btrfs_item_ptr(leaf, path->slots[0],
679 struct btrfs_file_extent_item);
681 read_extent_buffer(eb, &cmp1, (unsigned long)item,
683 read_extent_buffer(leaf, &cmp2, (unsigned long)existing,
687 * we already have a pointer to this exact extent,
688 * we don't have to do anything
690 if (memcmp(&cmp1, &cmp2, sizeof(cmp1)) == 0) {
691 btrfs_release_path(path);
695 btrfs_release_path(path);
697 /* drop any overlapping extents */
698 drop_args.start = start;
699 drop_args.end = extent_end;
700 drop_args.drop_cache = true;
701 ret = btrfs_drop_extents(trans, root, BTRFS_I(inode), &drop_args);
705 if (found_type == BTRFS_FILE_EXTENT_REG ||
706 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
708 unsigned long dest_offset;
709 struct btrfs_key ins;
711 if (btrfs_file_extent_disk_bytenr(eb, item) == 0 &&
712 btrfs_fs_incompat(fs_info, NO_HOLES))
715 ret = btrfs_insert_empty_item(trans, root, path, key,
719 dest_offset = btrfs_item_ptr_offset(path->nodes[0],
721 copy_extent_buffer(path->nodes[0], eb, dest_offset,
722 (unsigned long)item, sizeof(*item));
724 ins.objectid = btrfs_file_extent_disk_bytenr(eb, item);
725 ins.offset = btrfs_file_extent_disk_num_bytes(eb, item);
726 ins.type = BTRFS_EXTENT_ITEM_KEY;
727 offset = key->offset - btrfs_file_extent_offset(eb, item);
730 * Manually record dirty extent, as here we did a shallow
731 * file extent item copy and skip normal backref update,
732 * but modifying extent tree all by ourselves.
733 * So need to manually record dirty extent for qgroup,
734 * as the owner of the file extent changed from log tree
735 * (doesn't affect qgroup) to fs/file tree(affects qgroup)
737 ret = btrfs_qgroup_trace_extent(trans,
738 btrfs_file_extent_disk_bytenr(eb, item),
739 btrfs_file_extent_disk_num_bytes(eb, item),
744 if (ins.objectid > 0) {
745 struct btrfs_ref ref = { 0 };
748 LIST_HEAD(ordered_sums);
751 * is this extent already allocated in the extent
752 * allocation tree? If so, just add a reference
754 ret = btrfs_lookup_data_extent(fs_info, ins.objectid,
758 } else if (ret == 0) {
759 btrfs_init_generic_ref(&ref,
760 BTRFS_ADD_DELAYED_REF,
761 ins.objectid, ins.offset, 0);
762 btrfs_init_data_ref(&ref,
763 root->root_key.objectid,
764 key->objectid, offset, 0, false);
765 ret = btrfs_inc_extent_ref(trans, &ref);
770 * insert the extent pointer in the extent
773 ret = btrfs_alloc_logged_file_extent(trans,
774 root->root_key.objectid,
775 key->objectid, offset, &ins);
779 btrfs_release_path(path);
781 if (btrfs_file_extent_compression(eb, item)) {
782 csum_start = ins.objectid;
783 csum_end = csum_start + ins.offset;
785 csum_start = ins.objectid +
786 btrfs_file_extent_offset(eb, item);
787 csum_end = csum_start +
788 btrfs_file_extent_num_bytes(eb, item);
791 ret = btrfs_lookup_csums_range(root->log_root,
792 csum_start, csum_end - 1,
797 * Now delete all existing cums in the csum root that
798 * cover our range. We do this because we can have an
799 * extent that is completely referenced by one file
800 * extent item and partially referenced by another
801 * file extent item (like after using the clone or
802 * extent_same ioctls). In this case if we end up doing
803 * the replay of the one that partially references the
804 * extent first, and we do not do the csum deletion
805 * below, we can get 2 csum items in the csum tree that
806 * overlap each other. For example, imagine our log has
807 * the two following file extent items:
809 * key (257 EXTENT_DATA 409600)
810 * extent data disk byte 12845056 nr 102400
811 * extent data offset 20480 nr 20480 ram 102400
813 * key (257 EXTENT_DATA 819200)
814 * extent data disk byte 12845056 nr 102400
815 * extent data offset 0 nr 102400 ram 102400
817 * Where the second one fully references the 100K extent
818 * that starts at disk byte 12845056, and the log tree
819 * has a single csum item that covers the entire range
822 * key (EXTENT_CSUM EXTENT_CSUM 12845056) itemsize 100
824 * After the first file extent item is replayed, the
825 * csum tree gets the following csum item:
827 * key (EXTENT_CSUM EXTENT_CSUM 12865536) itemsize 20
829 * Which covers the 20K sub-range starting at offset 20K
830 * of our extent. Now when we replay the second file
831 * extent item, if we do not delete existing csum items
832 * that cover any of its blocks, we end up getting two
833 * csum items in our csum tree that overlap each other:
835 * key (EXTENT_CSUM EXTENT_CSUM 12845056) itemsize 100
836 * key (EXTENT_CSUM EXTENT_CSUM 12865536) itemsize 20
838 * Which is a problem, because after this anyone trying
839 * to lookup up for the checksum of any block of our
840 * extent starting at an offset of 40K or higher, will
841 * end up looking at the second csum item only, which
842 * does not contain the checksum for any block starting
843 * at offset 40K or higher of our extent.
845 while (!list_empty(&ordered_sums)) {
846 struct btrfs_ordered_sum *sums;
847 sums = list_entry(ordered_sums.next,
848 struct btrfs_ordered_sum,
851 ret = btrfs_del_csums(trans,
856 ret = btrfs_csum_file_blocks(trans,
857 fs_info->csum_root, sums);
858 list_del(&sums->list);
864 btrfs_release_path(path);
866 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
867 /* inline extents are easy, we just overwrite them */
868 ret = overwrite_item(trans, root, path, eb, slot, key);
873 ret = btrfs_inode_set_file_extent_range(BTRFS_I(inode), start,
879 btrfs_update_inode_bytes(BTRFS_I(inode), nbytes, drop_args.bytes_found);
880 ret = btrfs_update_inode(trans, root, BTRFS_I(inode));
888 * when cleaning up conflicts between the directory names in the
889 * subvolume, directory names in the log and directory names in the
890 * inode back references, we may have to unlink inodes from directories.
892 * This is a helper function to do the unlink of a specific directory
895 static noinline int drop_one_dir_item(struct btrfs_trans_handle *trans,
896 struct btrfs_root *root,
897 struct btrfs_path *path,
898 struct btrfs_inode *dir,
899 struct btrfs_dir_item *di)
904 struct extent_buffer *leaf;
905 struct btrfs_key location;
908 leaf = path->nodes[0];
910 btrfs_dir_item_key_to_cpu(leaf, di, &location);
911 name_len = btrfs_dir_name_len(leaf, di);
912 name = kmalloc(name_len, GFP_NOFS);
916 read_extent_buffer(leaf, name, (unsigned long)(di + 1), name_len);
917 btrfs_release_path(path);
919 inode = read_one_inode(root, location.objectid);
925 ret = link_to_fixup_dir(trans, root, path, location.objectid);
929 ret = btrfs_unlink_inode(trans, dir, BTRFS_I(inode), name,
934 ret = btrfs_run_delayed_items(trans);
942 * See if a given name and sequence number found in an inode back reference are
943 * already in a directory and correctly point to this inode.
945 * Returns: < 0 on error, 0 if the directory entry does not exists and 1 if it
948 static noinline int inode_in_dir(struct btrfs_root *root,
949 struct btrfs_path *path,
950 u64 dirid, u64 objectid, u64 index,
951 const char *name, int name_len)
953 struct btrfs_dir_item *di;
954 struct btrfs_key location;
957 di = btrfs_lookup_dir_index_item(NULL, root, path, dirid,
958 index, name, name_len, 0);
963 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location);
964 if (location.objectid != objectid)
970 btrfs_release_path(path);
971 di = btrfs_lookup_dir_item(NULL, root, path, dirid, name, name_len, 0);
976 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location);
977 if (location.objectid == objectid)
981 btrfs_release_path(path);
986 * helper function to check a log tree for a named back reference in
987 * an inode. This is used to decide if a back reference that is
988 * found in the subvolume conflicts with what we find in the log.
990 * inode backreferences may have multiple refs in a single item,
991 * during replay we process one reference at a time, and we don't
992 * want to delete valid links to a file from the subvolume if that
993 * link is also in the log.
995 static noinline int backref_in_log(struct btrfs_root *log,
996 struct btrfs_key *key,
998 const char *name, int namelen)
1000 struct btrfs_path *path;
1003 path = btrfs_alloc_path();
1007 ret = btrfs_search_slot(NULL, log, key, path, 0, 0);
1010 } else if (ret == 1) {
1015 if (key->type == BTRFS_INODE_EXTREF_KEY)
1016 ret = !!btrfs_find_name_in_ext_backref(path->nodes[0],
1021 ret = !!btrfs_find_name_in_backref(path->nodes[0],
1025 btrfs_free_path(path);
1029 static inline int __add_inode_ref(struct btrfs_trans_handle *trans,
1030 struct btrfs_root *root,
1031 struct btrfs_path *path,
1032 struct btrfs_root *log_root,
1033 struct btrfs_inode *dir,
1034 struct btrfs_inode *inode,
1035 u64 inode_objectid, u64 parent_objectid,
1036 u64 ref_index, char *name, int namelen,
1041 int victim_name_len;
1042 struct extent_buffer *leaf;
1043 struct btrfs_dir_item *di;
1044 struct btrfs_key search_key;
1045 struct btrfs_inode_extref *extref;
1048 /* Search old style refs */
1049 search_key.objectid = inode_objectid;
1050 search_key.type = BTRFS_INODE_REF_KEY;
1051 search_key.offset = parent_objectid;
1052 ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
1054 struct btrfs_inode_ref *victim_ref;
1056 unsigned long ptr_end;
1058 leaf = path->nodes[0];
1060 /* are we trying to overwrite a back ref for the root directory
1061 * if so, just jump out, we're done
1063 if (search_key.objectid == search_key.offset)
1066 /* check all the names in this back reference to see
1067 * if they are in the log. if so, we allow them to stay
1068 * otherwise they must be unlinked as a conflict
1070 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
1071 ptr_end = ptr + btrfs_item_size_nr(leaf, path->slots[0]);
1072 while (ptr < ptr_end) {
1073 victim_ref = (struct btrfs_inode_ref *)ptr;
1074 victim_name_len = btrfs_inode_ref_name_len(leaf,
1076 victim_name = kmalloc(victim_name_len, GFP_NOFS);
1080 read_extent_buffer(leaf, victim_name,
1081 (unsigned long)(victim_ref + 1),
1084 ret = backref_in_log(log_root, &search_key,
1085 parent_objectid, victim_name,
1091 inc_nlink(&inode->vfs_inode);
1092 btrfs_release_path(path);
1094 ret = btrfs_unlink_inode(trans, dir, inode,
1095 victim_name, victim_name_len);
1099 ret = btrfs_run_delayed_items(trans);
1107 ptr = (unsigned long)(victim_ref + 1) + victim_name_len;
1111 * NOTE: we have searched root tree and checked the
1112 * corresponding ref, it does not need to check again.
1116 btrfs_release_path(path);
1118 /* Same search but for extended refs */
1119 extref = btrfs_lookup_inode_extref(NULL, root, path, name, namelen,
1120 inode_objectid, parent_objectid, 0,
1122 if (IS_ERR(extref)) {
1123 return PTR_ERR(extref);
1124 } else if (extref) {
1128 struct inode *victim_parent;
1130 leaf = path->nodes[0];
1132 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1133 base = btrfs_item_ptr_offset(leaf, path->slots[0]);
1135 while (cur_offset < item_size) {
1136 extref = (struct btrfs_inode_extref *)(base + cur_offset);
1138 victim_name_len = btrfs_inode_extref_name_len(leaf, extref);
1140 if (btrfs_inode_extref_parent(leaf, extref) != parent_objectid)
1143 victim_name = kmalloc(victim_name_len, GFP_NOFS);
1146 read_extent_buffer(leaf, victim_name, (unsigned long)&extref->name,
1149 search_key.objectid = inode_objectid;
1150 search_key.type = BTRFS_INODE_EXTREF_KEY;
1151 search_key.offset = btrfs_extref_hash(parent_objectid,
1154 ret = backref_in_log(log_root, &search_key,
1155 parent_objectid, victim_name,
1162 victim_parent = read_one_inode(root,
1164 if (victim_parent) {
1165 inc_nlink(&inode->vfs_inode);
1166 btrfs_release_path(path);
1168 ret = btrfs_unlink_inode(trans,
1169 BTRFS_I(victim_parent),
1174 ret = btrfs_run_delayed_items(
1177 iput(victim_parent);
1186 cur_offset += victim_name_len + sizeof(*extref);
1190 btrfs_release_path(path);
1192 /* look for a conflicting sequence number */
1193 di = btrfs_lookup_dir_index_item(trans, root, path, btrfs_ino(dir),
1194 ref_index, name, namelen, 0);
1198 ret = drop_one_dir_item(trans, root, path, dir, di);
1202 btrfs_release_path(path);
1204 /* look for a conflicting name */
1205 di = btrfs_lookup_dir_item(trans, root, path, btrfs_ino(dir),
1210 ret = drop_one_dir_item(trans, root, path, dir, di);
1214 btrfs_release_path(path);
1219 static int extref_get_fields(struct extent_buffer *eb, unsigned long ref_ptr,
1220 u32 *namelen, char **name, u64 *index,
1221 u64 *parent_objectid)
1223 struct btrfs_inode_extref *extref;
1225 extref = (struct btrfs_inode_extref *)ref_ptr;
1227 *namelen = btrfs_inode_extref_name_len(eb, extref);
1228 *name = kmalloc(*namelen, GFP_NOFS);
1232 read_extent_buffer(eb, *name, (unsigned long)&extref->name,
1236 *index = btrfs_inode_extref_index(eb, extref);
1237 if (parent_objectid)
1238 *parent_objectid = btrfs_inode_extref_parent(eb, extref);
1243 static int ref_get_fields(struct extent_buffer *eb, unsigned long ref_ptr,
1244 u32 *namelen, char **name, u64 *index)
1246 struct btrfs_inode_ref *ref;
1248 ref = (struct btrfs_inode_ref *)ref_ptr;
1250 *namelen = btrfs_inode_ref_name_len(eb, ref);
1251 *name = kmalloc(*namelen, GFP_NOFS);
1255 read_extent_buffer(eb, *name, (unsigned long)(ref + 1), *namelen);
1258 *index = btrfs_inode_ref_index(eb, ref);
1264 * Take an inode reference item from the log tree and iterate all names from the
1265 * inode reference item in the subvolume tree with the same key (if it exists).
1266 * For any name that is not in the inode reference item from the log tree, do a
1267 * proper unlink of that name (that is, remove its entry from the inode
1268 * reference item and both dir index keys).
1270 static int unlink_old_inode_refs(struct btrfs_trans_handle *trans,
1271 struct btrfs_root *root,
1272 struct btrfs_path *path,
1273 struct btrfs_inode *inode,
1274 struct extent_buffer *log_eb,
1276 struct btrfs_key *key)
1279 unsigned long ref_ptr;
1280 unsigned long ref_end;
1281 struct extent_buffer *eb;
1284 btrfs_release_path(path);
1285 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
1293 eb = path->nodes[0];
1294 ref_ptr = btrfs_item_ptr_offset(eb, path->slots[0]);
1295 ref_end = ref_ptr + btrfs_item_size_nr(eb, path->slots[0]);
1296 while (ref_ptr < ref_end) {
1301 if (key->type == BTRFS_INODE_EXTREF_KEY) {
1302 ret = extref_get_fields(eb, ref_ptr, &namelen, &name,
1305 parent_id = key->offset;
1306 ret = ref_get_fields(eb, ref_ptr, &namelen, &name,
1312 if (key->type == BTRFS_INODE_EXTREF_KEY)
1313 ret = !!btrfs_find_name_in_ext_backref(log_eb, log_slot,
1317 ret = !!btrfs_find_name_in_backref(log_eb, log_slot,
1323 btrfs_release_path(path);
1324 dir = read_one_inode(root, parent_id);
1330 ret = btrfs_unlink_inode(trans, BTRFS_I(dir),
1331 inode, name, namelen);
1335 * Whenever we need to check if a name exists or not, we
1336 * check the subvolume tree. So after an unlink we must
1337 * run delayed items, so that future checks for a name
1338 * during log replay see that the name does not exists
1342 ret = btrfs_run_delayed_items(trans);
1350 if (key->type == BTRFS_INODE_EXTREF_KEY)
1351 ref_ptr += sizeof(struct btrfs_inode_extref);
1353 ref_ptr += sizeof(struct btrfs_inode_ref);
1357 btrfs_release_path(path);
1361 static int btrfs_inode_ref_exists(struct inode *inode, struct inode *dir,
1362 const u8 ref_type, const char *name,
1365 struct btrfs_key key;
1366 struct btrfs_path *path;
1367 const u64 parent_id = btrfs_ino(BTRFS_I(dir));
1370 path = btrfs_alloc_path();
1374 key.objectid = btrfs_ino(BTRFS_I(inode));
1375 key.type = ref_type;
1376 if (key.type == BTRFS_INODE_REF_KEY)
1377 key.offset = parent_id;
1379 key.offset = btrfs_extref_hash(parent_id, name, namelen);
1381 ret = btrfs_search_slot(NULL, BTRFS_I(inode)->root, &key, path, 0, 0);
1388 if (key.type == BTRFS_INODE_EXTREF_KEY)
1389 ret = !!btrfs_find_name_in_ext_backref(path->nodes[0],
1390 path->slots[0], parent_id, name, namelen);
1392 ret = !!btrfs_find_name_in_backref(path->nodes[0], path->slots[0],
1396 btrfs_free_path(path);
1400 static int add_link(struct btrfs_trans_handle *trans, struct btrfs_root *root,
1401 struct inode *dir, struct inode *inode, const char *name,
1402 int namelen, u64 ref_index)
1404 struct btrfs_dir_item *dir_item;
1405 struct btrfs_key key;
1406 struct btrfs_path *path;
1407 struct inode *other_inode = NULL;
1410 path = btrfs_alloc_path();
1414 dir_item = btrfs_lookup_dir_item(NULL, root, path,
1415 btrfs_ino(BTRFS_I(dir)),
1418 btrfs_release_path(path);
1420 } else if (IS_ERR(dir_item)) {
1421 ret = PTR_ERR(dir_item);
1426 * Our inode's dentry collides with the dentry of another inode which is
1427 * in the log but not yet processed since it has a higher inode number.
1428 * So delete that other dentry.
1430 btrfs_dir_item_key_to_cpu(path->nodes[0], dir_item, &key);
1431 btrfs_release_path(path);
1432 other_inode = read_one_inode(root, key.objectid);
1437 ret = btrfs_unlink_inode(trans, BTRFS_I(dir), BTRFS_I(other_inode),
1442 * If we dropped the link count to 0, bump it so that later the iput()
1443 * on the inode will not free it. We will fixup the link count later.
1445 if (other_inode->i_nlink == 0)
1446 inc_nlink(other_inode);
1448 ret = btrfs_run_delayed_items(trans);
1452 ret = btrfs_add_link(trans, BTRFS_I(dir), BTRFS_I(inode),
1453 name, namelen, 0, ref_index);
1456 btrfs_free_path(path);
1462 * replay one inode back reference item found in the log tree.
1463 * eb, slot and key refer to the buffer and key found in the log tree.
1464 * root is the destination we are replaying into, and path is for temp
1465 * use by this function. (it should be released on return).
1467 static noinline int add_inode_ref(struct btrfs_trans_handle *trans,
1468 struct btrfs_root *root,
1469 struct btrfs_root *log,
1470 struct btrfs_path *path,
1471 struct extent_buffer *eb, int slot,
1472 struct btrfs_key *key)
1474 struct inode *dir = NULL;
1475 struct inode *inode = NULL;
1476 unsigned long ref_ptr;
1477 unsigned long ref_end;
1481 int search_done = 0;
1482 int log_ref_ver = 0;
1483 u64 parent_objectid;
1486 int ref_struct_size;
1488 ref_ptr = btrfs_item_ptr_offset(eb, slot);
1489 ref_end = ref_ptr + btrfs_item_size_nr(eb, slot);
1491 if (key->type == BTRFS_INODE_EXTREF_KEY) {
1492 struct btrfs_inode_extref *r;
1494 ref_struct_size = sizeof(struct btrfs_inode_extref);
1496 r = (struct btrfs_inode_extref *)ref_ptr;
1497 parent_objectid = btrfs_inode_extref_parent(eb, r);
1499 ref_struct_size = sizeof(struct btrfs_inode_ref);
1500 parent_objectid = key->offset;
1502 inode_objectid = key->objectid;
1505 * it is possible that we didn't log all the parent directories
1506 * for a given inode. If we don't find the dir, just don't
1507 * copy the back ref in. The link count fixup code will take
1510 dir = read_one_inode(root, parent_objectid);
1516 inode = read_one_inode(root, inode_objectid);
1522 while (ref_ptr < ref_end) {
1524 ret = extref_get_fields(eb, ref_ptr, &namelen, &name,
1525 &ref_index, &parent_objectid);
1527 * parent object can change from one array
1531 dir = read_one_inode(root, parent_objectid);
1537 ret = ref_get_fields(eb, ref_ptr, &namelen, &name,
1543 ret = inode_in_dir(root, path, btrfs_ino(BTRFS_I(dir)),
1544 btrfs_ino(BTRFS_I(inode)), ref_index,
1548 } else if (ret == 0) {
1550 * look for a conflicting back reference in the
1551 * metadata. if we find one we have to unlink that name
1552 * of the file before we add our new link. Later on, we
1553 * overwrite any existing back reference, and we don't
1554 * want to create dangling pointers in the directory.
1558 ret = __add_inode_ref(trans, root, path, log,
1563 ref_index, name, namelen,
1573 * If a reference item already exists for this inode
1574 * with the same parent and name, but different index,
1575 * drop it and the corresponding directory index entries
1576 * from the parent before adding the new reference item
1577 * and dir index entries, otherwise we would fail with
1578 * -EEXIST returned from btrfs_add_link() below.
1580 ret = btrfs_inode_ref_exists(inode, dir, key->type,
1583 ret = btrfs_unlink_inode(trans,
1588 * If we dropped the link count to 0, bump it so
1589 * that later the iput() on the inode will not
1590 * free it. We will fixup the link count later.
1592 if (!ret && inode->i_nlink == 0)
1595 * Whenever we need to check if a name exists or
1596 * not, we check the subvolume tree. So after an
1597 * unlink we must run delayed items, so that future
1598 * checks for a name during log replay see that the
1599 * name does not exists anymore.
1602 ret = btrfs_run_delayed_items(trans);
1607 /* insert our name */
1608 ret = add_link(trans, root, dir, inode, name, namelen,
1613 ret = btrfs_update_inode(trans, root, BTRFS_I(inode));
1617 /* Else, ret == 1, we already have a perfect match, we're done. */
1619 ref_ptr = (unsigned long)(ref_ptr + ref_struct_size) + namelen;
1629 * Before we overwrite the inode reference item in the subvolume tree
1630 * with the item from the log tree, we must unlink all names from the
1631 * parent directory that are in the subvolume's tree inode reference
1632 * item, otherwise we end up with an inconsistent subvolume tree where
1633 * dir index entries exist for a name but there is no inode reference
1634 * item with the same name.
1636 ret = unlink_old_inode_refs(trans, root, path, BTRFS_I(inode), eb, slot,
1641 /* finally write the back reference in the inode */
1642 ret = overwrite_item(trans, root, path, eb, slot, key);
1644 btrfs_release_path(path);
1651 static int count_inode_extrefs(struct btrfs_root *root,
1652 struct btrfs_inode *inode, struct btrfs_path *path)
1656 unsigned int nlink = 0;
1659 u64 inode_objectid = btrfs_ino(inode);
1662 struct btrfs_inode_extref *extref;
1663 struct extent_buffer *leaf;
1666 ret = btrfs_find_one_extref(root, inode_objectid, offset, path,
1671 leaf = path->nodes[0];
1672 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1673 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
1676 while (cur_offset < item_size) {
1677 extref = (struct btrfs_inode_extref *) (ptr + cur_offset);
1678 name_len = btrfs_inode_extref_name_len(leaf, extref);
1682 cur_offset += name_len + sizeof(*extref);
1686 btrfs_release_path(path);
1688 btrfs_release_path(path);
1690 if (ret < 0 && ret != -ENOENT)
1695 static int count_inode_refs(struct btrfs_root *root,
1696 struct btrfs_inode *inode, struct btrfs_path *path)
1699 struct btrfs_key key;
1700 unsigned int nlink = 0;
1702 unsigned long ptr_end;
1704 u64 ino = btrfs_ino(inode);
1707 key.type = BTRFS_INODE_REF_KEY;
1708 key.offset = (u64)-1;
1711 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1715 if (path->slots[0] == 0)
1720 btrfs_item_key_to_cpu(path->nodes[0], &key,
1722 if (key.objectid != ino ||
1723 key.type != BTRFS_INODE_REF_KEY)
1725 ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
1726 ptr_end = ptr + btrfs_item_size_nr(path->nodes[0],
1728 while (ptr < ptr_end) {
1729 struct btrfs_inode_ref *ref;
1731 ref = (struct btrfs_inode_ref *)ptr;
1732 name_len = btrfs_inode_ref_name_len(path->nodes[0],
1734 ptr = (unsigned long)(ref + 1) + name_len;
1738 if (key.offset == 0)
1740 if (path->slots[0] > 0) {
1745 btrfs_release_path(path);
1747 btrfs_release_path(path);
1753 * There are a few corners where the link count of the file can't
1754 * be properly maintained during replay. So, instead of adding
1755 * lots of complexity to the log code, we just scan the backrefs
1756 * for any file that has been through replay.
1758 * The scan will update the link count on the inode to reflect the
1759 * number of back refs found. If it goes down to zero, the iput
1760 * will free the inode.
1762 static noinline int fixup_inode_link_count(struct btrfs_trans_handle *trans,
1763 struct btrfs_root *root,
1764 struct inode *inode)
1766 struct btrfs_path *path;
1769 u64 ino = btrfs_ino(BTRFS_I(inode));
1771 path = btrfs_alloc_path();
1775 ret = count_inode_refs(root, BTRFS_I(inode), path);
1781 ret = count_inode_extrefs(root, BTRFS_I(inode), path);
1789 if (nlink != inode->i_nlink) {
1790 set_nlink(inode, nlink);
1791 ret = btrfs_update_inode(trans, root, BTRFS_I(inode));
1795 BTRFS_I(inode)->index_cnt = (u64)-1;
1797 if (inode->i_nlink == 0) {
1798 if (S_ISDIR(inode->i_mode)) {
1799 ret = replay_dir_deletes(trans, root, NULL, path,
1804 ret = btrfs_insert_orphan_item(trans, root, ino);
1810 btrfs_free_path(path);
1814 static noinline int fixup_inode_link_counts(struct btrfs_trans_handle *trans,
1815 struct btrfs_root *root,
1816 struct btrfs_path *path)
1819 struct btrfs_key key;
1820 struct inode *inode;
1822 key.objectid = BTRFS_TREE_LOG_FIXUP_OBJECTID;
1823 key.type = BTRFS_ORPHAN_ITEM_KEY;
1824 key.offset = (u64)-1;
1826 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1832 if (path->slots[0] == 0)
1837 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1838 if (key.objectid != BTRFS_TREE_LOG_FIXUP_OBJECTID ||
1839 key.type != BTRFS_ORPHAN_ITEM_KEY)
1842 ret = btrfs_del_item(trans, root, path);
1846 btrfs_release_path(path);
1847 inode = read_one_inode(root, key.offset);
1853 ret = fixup_inode_link_count(trans, root, inode);
1859 * fixup on a directory may create new entries,
1860 * make sure we always look for the highset possible
1863 key.offset = (u64)-1;
1865 btrfs_release_path(path);
1871 * record a given inode in the fixup dir so we can check its link
1872 * count when replay is done. The link count is incremented here
1873 * so the inode won't go away until we check it
1875 static noinline int link_to_fixup_dir(struct btrfs_trans_handle *trans,
1876 struct btrfs_root *root,
1877 struct btrfs_path *path,
1880 struct btrfs_key key;
1882 struct inode *inode;
1884 inode = read_one_inode(root, objectid);
1888 key.objectid = BTRFS_TREE_LOG_FIXUP_OBJECTID;
1889 key.type = BTRFS_ORPHAN_ITEM_KEY;
1890 key.offset = objectid;
1892 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1894 btrfs_release_path(path);
1896 if (!inode->i_nlink)
1897 set_nlink(inode, 1);
1900 ret = btrfs_update_inode(trans, root, BTRFS_I(inode));
1901 } else if (ret == -EEXIST) {
1910 * when replaying the log for a directory, we only insert names
1911 * for inodes that actually exist. This means an fsync on a directory
1912 * does not implicitly fsync all the new files in it
1914 static noinline int insert_one_name(struct btrfs_trans_handle *trans,
1915 struct btrfs_root *root,
1916 u64 dirid, u64 index,
1917 char *name, int name_len,
1918 struct btrfs_key *location)
1920 struct inode *inode;
1924 inode = read_one_inode(root, location->objectid);
1928 dir = read_one_inode(root, dirid);
1934 ret = btrfs_add_link(trans, BTRFS_I(dir), BTRFS_I(inode), name,
1935 name_len, 1, index);
1937 /* FIXME, put inode into FIXUP list */
1945 * take a single entry in a log directory item and replay it into
1948 * if a conflicting item exists in the subdirectory already,
1949 * the inode it points to is unlinked and put into the link count
1952 * If a name from the log points to a file or directory that does
1953 * not exist in the FS, it is skipped. fsyncs on directories
1954 * do not force down inodes inside that directory, just changes to the
1955 * names or unlinks in a directory.
1957 * Returns < 0 on error, 0 if the name wasn't replayed (dentry points to a
1958 * non-existing inode) and 1 if the name was replayed.
1960 static noinline int replay_one_name(struct btrfs_trans_handle *trans,
1961 struct btrfs_root *root,
1962 struct btrfs_path *path,
1963 struct extent_buffer *eb,
1964 struct btrfs_dir_item *di,
1965 struct btrfs_key *key)
1969 struct btrfs_dir_item *dst_di;
1970 struct btrfs_key found_key;
1971 struct btrfs_key log_key;
1976 bool update_size = (key->type == BTRFS_DIR_INDEX_KEY);
1977 bool name_added = false;
1979 dir = read_one_inode(root, key->objectid);
1983 name_len = btrfs_dir_name_len(eb, di);
1984 name = kmalloc(name_len, GFP_NOFS);
1990 log_type = btrfs_dir_type(eb, di);
1991 read_extent_buffer(eb, name, (unsigned long)(di + 1),
1994 btrfs_dir_item_key_to_cpu(eb, di, &log_key);
1995 ret = btrfs_lookup_inode(trans, root, path, &log_key, 0);
1996 btrfs_release_path(path);
1999 exists = (ret == 0);
2002 if (key->type == BTRFS_DIR_ITEM_KEY) {
2003 dst_di = btrfs_lookup_dir_item(trans, root, path, key->objectid,
2005 } else if (key->type == BTRFS_DIR_INDEX_KEY) {
2006 dst_di = btrfs_lookup_dir_index_item(trans, root, path,
2016 if (IS_ERR(dst_di)) {
2017 ret = PTR_ERR(dst_di);
2019 } else if (!dst_di) {
2020 /* we need a sequence number to insert, so we only
2021 * do inserts for the BTRFS_DIR_INDEX_KEY types
2023 if (key->type != BTRFS_DIR_INDEX_KEY)
2028 btrfs_dir_item_key_to_cpu(path->nodes[0], dst_di, &found_key);
2029 /* the existing item matches the logged item */
2030 if (found_key.objectid == log_key.objectid &&
2031 found_key.type == log_key.type &&
2032 found_key.offset == log_key.offset &&
2033 btrfs_dir_type(path->nodes[0], dst_di) == log_type) {
2034 update_size = false;
2039 * don't drop the conflicting directory entry if the inode
2040 * for the new entry doesn't exist
2045 ret = drop_one_dir_item(trans, root, path, BTRFS_I(dir), dst_di);
2049 if (key->type == BTRFS_DIR_INDEX_KEY)
2052 btrfs_release_path(path);
2053 if (!ret && update_size) {
2054 btrfs_i_size_write(BTRFS_I(dir), dir->i_size + name_len * 2);
2055 ret = btrfs_update_inode(trans, root, BTRFS_I(dir));
2059 if (!ret && name_added)
2065 * Check if the inode reference exists in the log for the given name,
2066 * inode and parent inode
2068 found_key.objectid = log_key.objectid;
2069 found_key.type = BTRFS_INODE_REF_KEY;
2070 found_key.offset = key->objectid;
2071 ret = backref_in_log(root->log_root, &found_key, 0, name, name_len);
2075 /* The dentry will be added later. */
2077 update_size = false;
2081 found_key.objectid = log_key.objectid;
2082 found_key.type = BTRFS_INODE_EXTREF_KEY;
2083 found_key.offset = key->objectid;
2084 ret = backref_in_log(root->log_root, &found_key, key->objectid, name,
2089 /* The dentry will be added later. */
2091 update_size = false;
2094 btrfs_release_path(path);
2095 ret = insert_one_name(trans, root, key->objectid, key->offset,
2096 name, name_len, &log_key);
2097 if (ret && ret != -ENOENT && ret != -EEXIST)
2101 update_size = false;
2107 * find all the names in a directory item and reconcile them into
2108 * the subvolume. Only BTRFS_DIR_ITEM_KEY types will have more than
2109 * one name in a directory item, but the same code gets used for
2110 * both directory index types
2112 static noinline int replay_one_dir_item(struct btrfs_trans_handle *trans,
2113 struct btrfs_root *root,
2114 struct btrfs_path *path,
2115 struct extent_buffer *eb, int slot,
2116 struct btrfs_key *key)
2119 u32 item_size = btrfs_item_size_nr(eb, slot);
2120 struct btrfs_dir_item *di;
2123 unsigned long ptr_end;
2124 struct btrfs_path *fixup_path = NULL;
2126 ptr = btrfs_item_ptr_offset(eb, slot);
2127 ptr_end = ptr + item_size;
2128 while (ptr < ptr_end) {
2129 di = (struct btrfs_dir_item *)ptr;
2130 name_len = btrfs_dir_name_len(eb, di);
2131 ret = replay_one_name(trans, root, path, eb, di, key);
2134 ptr = (unsigned long)(di + 1);
2138 * If this entry refers to a non-directory (directories can not
2139 * have a link count > 1) and it was added in the transaction
2140 * that was not committed, make sure we fixup the link count of
2141 * the inode it the entry points to. Otherwise something like
2142 * the following would result in a directory pointing to an
2143 * inode with a wrong link that does not account for this dir
2151 * ln testdir/bar testdir/bar_link
2152 * ln testdir/foo testdir/foo_link
2153 * xfs_io -c "fsync" testdir/bar
2157 * mount fs, log replay happens
2159 * File foo would remain with a link count of 1 when it has two
2160 * entries pointing to it in the directory testdir. This would
2161 * make it impossible to ever delete the parent directory has
2162 * it would result in stale dentries that can never be deleted.
2164 if (ret == 1 && btrfs_dir_type(eb, di) != BTRFS_FT_DIR) {
2165 struct btrfs_key di_key;
2168 fixup_path = btrfs_alloc_path();
2175 btrfs_dir_item_key_to_cpu(eb, di, &di_key);
2176 ret = link_to_fixup_dir(trans, root, fixup_path,
2183 btrfs_free_path(fixup_path);
2188 * directory replay has two parts. There are the standard directory
2189 * items in the log copied from the subvolume, and range items
2190 * created in the log while the subvolume was logged.
2192 * The range items tell us which parts of the key space the log
2193 * is authoritative for. During replay, if a key in the subvolume
2194 * directory is in a logged range item, but not actually in the log
2195 * that means it was deleted from the directory before the fsync
2196 * and should be removed.
2198 static noinline int find_dir_range(struct btrfs_root *root,
2199 struct btrfs_path *path,
2201 u64 *start_ret, u64 *end_ret)
2203 struct btrfs_key key;
2205 struct btrfs_dir_log_item *item;
2209 if (*start_ret == (u64)-1)
2212 key.objectid = dirid;
2213 key.type = BTRFS_DIR_LOG_INDEX_KEY;
2214 key.offset = *start_ret;
2216 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2220 if (path->slots[0] == 0)
2225 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
2227 if (key.type != BTRFS_DIR_LOG_INDEX_KEY || key.objectid != dirid) {
2231 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2232 struct btrfs_dir_log_item);
2233 found_end = btrfs_dir_log_end(path->nodes[0], item);
2235 if (*start_ret >= key.offset && *start_ret <= found_end) {
2237 *start_ret = key.offset;
2238 *end_ret = found_end;
2243 /* check the next slot in the tree to see if it is a valid item */
2244 nritems = btrfs_header_nritems(path->nodes[0]);
2246 if (path->slots[0] >= nritems) {
2247 ret = btrfs_next_leaf(root, path);
2252 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
2254 if (key.type != BTRFS_DIR_LOG_INDEX_KEY || key.objectid != dirid) {
2258 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2259 struct btrfs_dir_log_item);
2260 found_end = btrfs_dir_log_end(path->nodes[0], item);
2261 *start_ret = key.offset;
2262 *end_ret = found_end;
2265 btrfs_release_path(path);
2270 * this looks for a given directory item in the log. If the directory
2271 * item is not in the log, the item is removed and the inode it points
2274 static noinline int check_item_in_log(struct btrfs_trans_handle *trans,
2275 struct btrfs_root *root,
2276 struct btrfs_root *log,
2277 struct btrfs_path *path,
2278 struct btrfs_path *log_path,
2280 struct btrfs_key *dir_key)
2283 struct extent_buffer *eb;
2285 struct btrfs_dir_item *di;
2288 struct inode *inode = NULL;
2289 struct btrfs_key location;
2292 * Currenly we only log dir index keys. Even if we replay a log created
2293 * by an older kernel that logged both dir index and dir item keys, all
2294 * we need to do is process the dir index keys, we (and our caller) can
2295 * safely ignore dir item keys (key type BTRFS_DIR_ITEM_KEY).
2297 ASSERT(dir_key->type == BTRFS_DIR_INDEX_KEY);
2299 eb = path->nodes[0];
2300 slot = path->slots[0];
2301 di = btrfs_item_ptr(eb, slot, struct btrfs_dir_item);
2302 name_len = btrfs_dir_name_len(eb, di);
2303 name = kmalloc(name_len, GFP_NOFS);
2309 read_extent_buffer(eb, name, (unsigned long)(di + 1), name_len);
2312 struct btrfs_dir_item *log_di;
2314 log_di = btrfs_lookup_dir_index_item(trans, log, log_path,
2318 if (IS_ERR(log_di)) {
2319 ret = PTR_ERR(log_di);
2321 } else if (log_di) {
2322 /* The dentry exists in the log, we have nothing to do. */
2328 btrfs_dir_item_key_to_cpu(eb, di, &location);
2329 btrfs_release_path(path);
2330 btrfs_release_path(log_path);
2331 inode = read_one_inode(root, location.objectid);
2337 ret = link_to_fixup_dir(trans, root, path, location.objectid);
2342 ret = btrfs_unlink_inode(trans, BTRFS_I(dir), BTRFS_I(inode), name,
2347 ret = btrfs_run_delayed_items(trans);
2352 * Unlike dir item keys, dir index keys can only have one name (entry) in
2353 * them, as there are no key collisions since each key has a unique offset
2354 * (an index number), so we're done.
2357 btrfs_release_path(path);
2358 btrfs_release_path(log_path);
2364 static int replay_xattr_deletes(struct btrfs_trans_handle *trans,
2365 struct btrfs_root *root,
2366 struct btrfs_root *log,
2367 struct btrfs_path *path,
2370 struct btrfs_key search_key;
2371 struct btrfs_path *log_path;
2376 log_path = btrfs_alloc_path();
2380 search_key.objectid = ino;
2381 search_key.type = BTRFS_XATTR_ITEM_KEY;
2382 search_key.offset = 0;
2384 ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
2388 nritems = btrfs_header_nritems(path->nodes[0]);
2389 for (i = path->slots[0]; i < nritems; i++) {
2390 struct btrfs_key key;
2391 struct btrfs_dir_item *di;
2392 struct btrfs_dir_item *log_di;
2396 btrfs_item_key_to_cpu(path->nodes[0], &key, i);
2397 if (key.objectid != ino || key.type != BTRFS_XATTR_ITEM_KEY) {
2402 di = btrfs_item_ptr(path->nodes[0], i, struct btrfs_dir_item);
2403 total_size = btrfs_item_size_nr(path->nodes[0], i);
2405 while (cur < total_size) {
2406 u16 name_len = btrfs_dir_name_len(path->nodes[0], di);
2407 u16 data_len = btrfs_dir_data_len(path->nodes[0], di);
2408 u32 this_len = sizeof(*di) + name_len + data_len;
2411 name = kmalloc(name_len, GFP_NOFS);
2416 read_extent_buffer(path->nodes[0], name,
2417 (unsigned long)(di + 1), name_len);
2419 log_di = btrfs_lookup_xattr(NULL, log, log_path, ino,
2421 btrfs_release_path(log_path);
2423 /* Doesn't exist in log tree, so delete it. */
2424 btrfs_release_path(path);
2425 di = btrfs_lookup_xattr(trans, root, path, ino,
2426 name, name_len, -1);
2433 ret = btrfs_delete_one_dir_name(trans, root,
2437 btrfs_release_path(path);
2442 if (IS_ERR(log_di)) {
2443 ret = PTR_ERR(log_di);
2447 di = (struct btrfs_dir_item *)((char *)di + this_len);
2450 ret = btrfs_next_leaf(root, path);
2456 btrfs_free_path(log_path);
2457 btrfs_release_path(path);
2463 * deletion replay happens before we copy any new directory items
2464 * out of the log or out of backreferences from inodes. It
2465 * scans the log to find ranges of keys that log is authoritative for,
2466 * and then scans the directory to find items in those ranges that are
2467 * not present in the log.
2469 * Anything we don't find in the log is unlinked and removed from the
2472 static noinline int replay_dir_deletes(struct btrfs_trans_handle *trans,
2473 struct btrfs_root *root,
2474 struct btrfs_root *log,
2475 struct btrfs_path *path,
2476 u64 dirid, int del_all)
2481 struct btrfs_key dir_key;
2482 struct btrfs_key found_key;
2483 struct btrfs_path *log_path;
2486 dir_key.objectid = dirid;
2487 dir_key.type = BTRFS_DIR_INDEX_KEY;
2488 log_path = btrfs_alloc_path();
2492 dir = read_one_inode(root, dirid);
2493 /* it isn't an error if the inode isn't there, that can happen
2494 * because we replay the deletes before we copy in the inode item
2498 btrfs_free_path(log_path);
2506 range_end = (u64)-1;
2508 ret = find_dir_range(log, path, dirid,
2509 &range_start, &range_end);
2516 dir_key.offset = range_start;
2519 ret = btrfs_search_slot(NULL, root, &dir_key, path,
2524 nritems = btrfs_header_nritems(path->nodes[0]);
2525 if (path->slots[0] >= nritems) {
2526 ret = btrfs_next_leaf(root, path);
2532 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
2534 if (found_key.objectid != dirid ||
2535 found_key.type != dir_key.type) {
2540 if (found_key.offset > range_end)
2543 ret = check_item_in_log(trans, root, log, path,
2548 if (found_key.offset == (u64)-1)
2550 dir_key.offset = found_key.offset + 1;
2552 btrfs_release_path(path);
2553 if (range_end == (u64)-1)
2555 range_start = range_end + 1;
2559 btrfs_release_path(path);
2560 btrfs_free_path(log_path);
2566 * the process_func used to replay items from the log tree. This
2567 * gets called in two different stages. The first stage just looks
2568 * for inodes and makes sure they are all copied into the subvolume.
2570 * The second stage copies all the other item types from the log into
2571 * the subvolume. The two stage approach is slower, but gets rid of
2572 * lots of complexity around inodes referencing other inodes that exist
2573 * only in the log (references come from either directory items or inode
2576 static int replay_one_buffer(struct btrfs_root *log, struct extent_buffer *eb,
2577 struct walk_control *wc, u64 gen, int level)
2580 struct btrfs_path *path;
2581 struct btrfs_root *root = wc->replay_dest;
2582 struct btrfs_key key;
2586 ret = btrfs_read_buffer(eb, gen, level, NULL);
2590 level = btrfs_header_level(eb);
2595 path = btrfs_alloc_path();
2599 nritems = btrfs_header_nritems(eb);
2600 for (i = 0; i < nritems; i++) {
2601 btrfs_item_key_to_cpu(eb, &key, i);
2603 /* inode keys are done during the first stage */
2604 if (key.type == BTRFS_INODE_ITEM_KEY &&
2605 wc->stage == LOG_WALK_REPLAY_INODES) {
2606 struct btrfs_inode_item *inode_item;
2609 inode_item = btrfs_item_ptr(eb, i,
2610 struct btrfs_inode_item);
2612 * If we have a tmpfile (O_TMPFILE) that got fsync'ed
2613 * and never got linked before the fsync, skip it, as
2614 * replaying it is pointless since it would be deleted
2615 * later. We skip logging tmpfiles, but it's always
2616 * possible we are replaying a log created with a kernel
2617 * that used to log tmpfiles.
2619 if (btrfs_inode_nlink(eb, inode_item) == 0) {
2620 wc->ignore_cur_inode = true;
2623 wc->ignore_cur_inode = false;
2625 ret = replay_xattr_deletes(wc->trans, root, log,
2626 path, key.objectid);
2629 mode = btrfs_inode_mode(eb, inode_item);
2630 if (S_ISDIR(mode)) {
2631 ret = replay_dir_deletes(wc->trans,
2632 root, log, path, key.objectid, 0);
2636 ret = overwrite_item(wc->trans, root, path,
2642 * Before replaying extents, truncate the inode to its
2643 * size. We need to do it now and not after log replay
2644 * because before an fsync we can have prealloc extents
2645 * added beyond the inode's i_size. If we did it after,
2646 * through orphan cleanup for example, we would drop
2647 * those prealloc extents just after replaying them.
2649 if (S_ISREG(mode)) {
2650 struct btrfs_drop_extents_args drop_args = { 0 };
2651 struct inode *inode;
2654 inode = read_one_inode(root, key.objectid);
2659 from = ALIGN(i_size_read(inode),
2660 root->fs_info->sectorsize);
2661 drop_args.start = from;
2662 drop_args.end = (u64)-1;
2663 drop_args.drop_cache = true;
2664 ret = btrfs_drop_extents(wc->trans, root,
2668 inode_sub_bytes(inode,
2669 drop_args.bytes_found);
2670 /* Update the inode's nbytes. */
2671 ret = btrfs_update_inode(wc->trans,
2672 root, BTRFS_I(inode));
2679 ret = link_to_fixup_dir(wc->trans, root,
2680 path, key.objectid);
2685 if (wc->ignore_cur_inode)
2688 if (key.type == BTRFS_DIR_INDEX_KEY &&
2689 wc->stage == LOG_WALK_REPLAY_DIR_INDEX) {
2690 ret = replay_one_dir_item(wc->trans, root, path,
2696 if (wc->stage < LOG_WALK_REPLAY_ALL)
2699 /* these keys are simply copied */
2700 if (key.type == BTRFS_XATTR_ITEM_KEY) {
2701 ret = overwrite_item(wc->trans, root, path,
2705 } else if (key.type == BTRFS_INODE_REF_KEY ||
2706 key.type == BTRFS_INODE_EXTREF_KEY) {
2707 ret = add_inode_ref(wc->trans, root, log, path,
2709 if (ret && ret != -ENOENT)
2712 } else if (key.type == BTRFS_EXTENT_DATA_KEY) {
2713 ret = replay_one_extent(wc->trans, root, path,
2717 } else if (key.type == BTRFS_DIR_ITEM_KEY) {
2718 ret = replay_one_dir_item(wc->trans, root, path,
2724 btrfs_free_path(path);
2729 * Correctly adjust the reserved bytes occupied by a log tree extent buffer
2731 static void unaccount_log_buffer(struct btrfs_fs_info *fs_info, u64 start)
2733 struct btrfs_block_group *cache;
2735 cache = btrfs_lookup_block_group(fs_info, start);
2737 btrfs_err(fs_info, "unable to find block group for %llu", start);
2741 spin_lock(&cache->space_info->lock);
2742 spin_lock(&cache->lock);
2743 cache->reserved -= fs_info->nodesize;
2744 cache->space_info->bytes_reserved -= fs_info->nodesize;
2745 spin_unlock(&cache->lock);
2746 spin_unlock(&cache->space_info->lock);
2748 btrfs_put_block_group(cache);
2751 static noinline int walk_down_log_tree(struct btrfs_trans_handle *trans,
2752 struct btrfs_root *root,
2753 struct btrfs_path *path, int *level,
2754 struct walk_control *wc)
2756 struct btrfs_fs_info *fs_info = root->fs_info;
2759 struct extent_buffer *next;
2760 struct extent_buffer *cur;
2764 while (*level > 0) {
2765 struct btrfs_key first_key;
2767 cur = path->nodes[*level];
2769 WARN_ON(btrfs_header_level(cur) != *level);
2771 if (path->slots[*level] >=
2772 btrfs_header_nritems(cur))
2775 bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
2776 ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
2777 btrfs_node_key_to_cpu(cur, &first_key, path->slots[*level]);
2778 blocksize = fs_info->nodesize;
2780 next = btrfs_find_create_tree_block(fs_info, bytenr,
2781 btrfs_header_owner(cur),
2784 return PTR_ERR(next);
2787 ret = wc->process_func(root, next, wc, ptr_gen,
2790 free_extent_buffer(next);
2794 path->slots[*level]++;
2796 ret = btrfs_read_buffer(next, ptr_gen,
2797 *level - 1, &first_key);
2799 free_extent_buffer(next);
2804 btrfs_tree_lock(next);
2805 btrfs_clean_tree_block(next);
2806 btrfs_wait_tree_block_writeback(next);
2807 btrfs_tree_unlock(next);
2808 ret = btrfs_pin_reserved_extent(trans,
2811 free_extent_buffer(next);
2814 btrfs_redirty_list_add(
2815 trans->transaction, next);
2817 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &next->bflags))
2818 clear_extent_buffer_dirty(next);
2819 unaccount_log_buffer(fs_info, bytenr);
2822 free_extent_buffer(next);
2825 ret = btrfs_read_buffer(next, ptr_gen, *level - 1, &first_key);
2827 free_extent_buffer(next);
2831 if (path->nodes[*level-1])
2832 free_extent_buffer(path->nodes[*level-1]);
2833 path->nodes[*level-1] = next;
2834 *level = btrfs_header_level(next);
2835 path->slots[*level] = 0;
2838 path->slots[*level] = btrfs_header_nritems(path->nodes[*level]);
2844 static noinline int walk_up_log_tree(struct btrfs_trans_handle *trans,
2845 struct btrfs_root *root,
2846 struct btrfs_path *path, int *level,
2847 struct walk_control *wc)
2849 struct btrfs_fs_info *fs_info = root->fs_info;
2854 for (i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
2855 slot = path->slots[i];
2856 if (slot + 1 < btrfs_header_nritems(path->nodes[i])) {
2859 WARN_ON(*level == 0);
2862 ret = wc->process_func(root, path->nodes[*level], wc,
2863 btrfs_header_generation(path->nodes[*level]),
2869 struct extent_buffer *next;
2871 next = path->nodes[*level];
2874 btrfs_tree_lock(next);
2875 btrfs_clean_tree_block(next);
2876 btrfs_wait_tree_block_writeback(next);
2877 btrfs_tree_unlock(next);
2878 ret = btrfs_pin_reserved_extent(trans,
2879 path->nodes[*level]->start,
2880 path->nodes[*level]->len);
2883 btrfs_redirty_list_add(trans->transaction,
2886 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &next->bflags))
2887 clear_extent_buffer_dirty(next);
2889 unaccount_log_buffer(fs_info,
2890 path->nodes[*level]->start);
2893 free_extent_buffer(path->nodes[*level]);
2894 path->nodes[*level] = NULL;
2902 * drop the reference count on the tree rooted at 'snap'. This traverses
2903 * the tree freeing any blocks that have a ref count of zero after being
2906 static int walk_log_tree(struct btrfs_trans_handle *trans,
2907 struct btrfs_root *log, struct walk_control *wc)
2909 struct btrfs_fs_info *fs_info = log->fs_info;
2913 struct btrfs_path *path;
2916 path = btrfs_alloc_path();
2920 level = btrfs_header_level(log->node);
2922 path->nodes[level] = log->node;
2923 atomic_inc(&log->node->refs);
2924 path->slots[level] = 0;
2927 wret = walk_down_log_tree(trans, log, path, &level, wc);
2935 wret = walk_up_log_tree(trans, log, path, &level, wc);
2944 /* was the root node processed? if not, catch it here */
2945 if (path->nodes[orig_level]) {
2946 ret = wc->process_func(log, path->nodes[orig_level], wc,
2947 btrfs_header_generation(path->nodes[orig_level]),
2952 struct extent_buffer *next;
2954 next = path->nodes[orig_level];
2957 btrfs_tree_lock(next);
2958 btrfs_clean_tree_block(next);
2959 btrfs_wait_tree_block_writeback(next);
2960 btrfs_tree_unlock(next);
2961 ret = btrfs_pin_reserved_extent(trans,
2962 next->start, next->len);
2965 btrfs_redirty_list_add(trans->transaction, next);
2967 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &next->bflags))
2968 clear_extent_buffer_dirty(next);
2969 unaccount_log_buffer(fs_info, next->start);
2975 btrfs_free_path(path);
2980 * helper function to update the item for a given subvolumes log root
2981 * in the tree of log roots
2983 static int update_log_root(struct btrfs_trans_handle *trans,
2984 struct btrfs_root *log,
2985 struct btrfs_root_item *root_item)
2987 struct btrfs_fs_info *fs_info = log->fs_info;
2990 if (log->log_transid == 1) {
2991 /* insert root item on the first sync */
2992 ret = btrfs_insert_root(trans, fs_info->log_root_tree,
2993 &log->root_key, root_item);
2995 ret = btrfs_update_root(trans, fs_info->log_root_tree,
2996 &log->root_key, root_item);
3001 static void wait_log_commit(struct btrfs_root *root, int transid)
3004 int index = transid % 2;
3007 * we only allow two pending log transactions at a time,
3008 * so we know that if ours is more than 2 older than the
3009 * current transaction, we're done
3012 prepare_to_wait(&root->log_commit_wait[index],
3013 &wait, TASK_UNINTERRUPTIBLE);
3015 if (!(root->log_transid_committed < transid &&
3016 atomic_read(&root->log_commit[index])))
3019 mutex_unlock(&root->log_mutex);
3021 mutex_lock(&root->log_mutex);
3023 finish_wait(&root->log_commit_wait[index], &wait);
3026 static void wait_for_writer(struct btrfs_root *root)
3031 prepare_to_wait(&root->log_writer_wait, &wait,
3032 TASK_UNINTERRUPTIBLE);
3033 if (!atomic_read(&root->log_writers))
3036 mutex_unlock(&root->log_mutex);
3038 mutex_lock(&root->log_mutex);
3040 finish_wait(&root->log_writer_wait, &wait);
3043 static inline void btrfs_remove_log_ctx(struct btrfs_root *root,
3044 struct btrfs_log_ctx *ctx)
3049 mutex_lock(&root->log_mutex);
3050 list_del_init(&ctx->list);
3051 mutex_unlock(&root->log_mutex);
3055 * Invoked in log mutex context, or be sure there is no other task which
3056 * can access the list.
3058 static inline void btrfs_remove_all_log_ctxs(struct btrfs_root *root,
3059 int index, int error)
3061 struct btrfs_log_ctx *ctx;
3062 struct btrfs_log_ctx *safe;
3064 list_for_each_entry_safe(ctx, safe, &root->log_ctxs[index], list) {
3065 list_del_init(&ctx->list);
3066 ctx->log_ret = error;
3071 * btrfs_sync_log does sends a given tree log down to the disk and
3072 * updates the super blocks to record it. When this call is done,
3073 * you know that any inodes previously logged are safely on disk only
3076 * Any other return value means you need to call btrfs_commit_transaction.
3077 * Some of the edge cases for fsyncing directories that have had unlinks
3078 * or renames done in the past mean that sometimes the only safe
3079 * fsync is to commit the whole FS. When btrfs_sync_log returns -EAGAIN,
3080 * that has happened.
3082 int btrfs_sync_log(struct btrfs_trans_handle *trans,
3083 struct btrfs_root *root, struct btrfs_log_ctx *ctx)
3089 struct btrfs_fs_info *fs_info = root->fs_info;
3090 struct btrfs_root *log = root->log_root;
3091 struct btrfs_root *log_root_tree = fs_info->log_root_tree;
3092 struct btrfs_root_item new_root_item;
3093 int log_transid = 0;
3094 struct btrfs_log_ctx root_log_ctx;
3095 struct blk_plug plug;
3099 mutex_lock(&root->log_mutex);
3100 log_transid = ctx->log_transid;
3101 if (root->log_transid_committed >= log_transid) {
3102 mutex_unlock(&root->log_mutex);
3103 return ctx->log_ret;
3106 index1 = log_transid % 2;
3107 if (atomic_read(&root->log_commit[index1])) {
3108 wait_log_commit(root, log_transid);
3109 mutex_unlock(&root->log_mutex);
3110 return ctx->log_ret;
3112 ASSERT(log_transid == root->log_transid);
3113 atomic_set(&root->log_commit[index1], 1);
3115 /* wait for previous tree log sync to complete */
3116 if (atomic_read(&root->log_commit[(index1 + 1) % 2]))
3117 wait_log_commit(root, log_transid - 1);
3120 int batch = atomic_read(&root->log_batch);
3121 /* when we're on an ssd, just kick the log commit out */
3122 if (!btrfs_test_opt(fs_info, SSD) &&
3123 test_bit(BTRFS_ROOT_MULTI_LOG_TASKS, &root->state)) {
3124 mutex_unlock(&root->log_mutex);
3125 schedule_timeout_uninterruptible(1);
3126 mutex_lock(&root->log_mutex);
3128 wait_for_writer(root);
3129 if (batch == atomic_read(&root->log_batch))
3133 /* bail out if we need to do a full commit */
3134 if (btrfs_need_log_full_commit(trans)) {
3136 mutex_unlock(&root->log_mutex);
3140 if (log_transid % 2 == 0)
3141 mark = EXTENT_DIRTY;
3145 /* we start IO on all the marked extents here, but we don't actually
3146 * wait for them until later.
3148 blk_start_plug(&plug);
3149 ret = btrfs_write_marked_extents(fs_info, &log->dirty_log_pages, mark);
3151 * -EAGAIN happens when someone, e.g., a concurrent transaction
3152 * commit, writes a dirty extent in this tree-log commit. This
3153 * concurrent write will create a hole writing out the extents,
3154 * and we cannot proceed on a zoned filesystem, requiring
3155 * sequential writing. While we can bail out to a full commit
3156 * here, but we can continue hoping the concurrent writing fills
3159 if (ret == -EAGAIN && btrfs_is_zoned(fs_info))
3162 blk_finish_plug(&plug);
3163 btrfs_abort_transaction(trans, ret);
3164 btrfs_set_log_full_commit(trans);
3165 mutex_unlock(&root->log_mutex);
3170 * We _must_ update under the root->log_mutex in order to make sure we
3171 * have a consistent view of the log root we are trying to commit at
3174 * We _must_ copy this into a local copy, because we are not holding the
3175 * log_root_tree->log_mutex yet. This is important because when we
3176 * commit the log_root_tree we must have a consistent view of the
3177 * log_root_tree when we update the super block to point at the
3178 * log_root_tree bytenr. If we update the log_root_tree here we'll race
3179 * with the commit and possibly point at the new block which we may not
3182 btrfs_set_root_node(&log->root_item, log->node);
3183 memcpy(&new_root_item, &log->root_item, sizeof(new_root_item));
3185 root->log_transid++;
3186 log->log_transid = root->log_transid;
3187 root->log_start_pid = 0;
3189 * IO has been started, blocks of the log tree have WRITTEN flag set
3190 * in their headers. new modifications of the log will be written to
3191 * new positions. so it's safe to allow log writers to go in.
3193 mutex_unlock(&root->log_mutex);
3195 if (btrfs_is_zoned(fs_info)) {
3196 mutex_lock(&fs_info->tree_root->log_mutex);
3197 if (!log_root_tree->node) {
3198 ret = btrfs_alloc_log_tree_node(trans, log_root_tree);
3200 mutex_unlock(&fs_info->tree_root->log_mutex);
3201 blk_finish_plug(&plug);
3205 mutex_unlock(&fs_info->tree_root->log_mutex);
3208 btrfs_init_log_ctx(&root_log_ctx, NULL);
3210 mutex_lock(&log_root_tree->log_mutex);
3212 index2 = log_root_tree->log_transid % 2;
3213 list_add_tail(&root_log_ctx.list, &log_root_tree->log_ctxs[index2]);
3214 root_log_ctx.log_transid = log_root_tree->log_transid;
3217 * Now we are safe to update the log_root_tree because we're under the
3218 * log_mutex, and we're a current writer so we're holding the commit
3219 * open until we drop the log_mutex.
3221 ret = update_log_root(trans, log, &new_root_item);
3223 if (!list_empty(&root_log_ctx.list))
3224 list_del_init(&root_log_ctx.list);
3226 blk_finish_plug(&plug);
3227 btrfs_set_log_full_commit(trans);
3229 if (ret != -ENOSPC) {
3230 btrfs_abort_transaction(trans, ret);
3231 mutex_unlock(&log_root_tree->log_mutex);
3234 btrfs_wait_tree_log_extents(log, mark);
3235 mutex_unlock(&log_root_tree->log_mutex);
3240 if (log_root_tree->log_transid_committed >= root_log_ctx.log_transid) {
3241 blk_finish_plug(&plug);
3242 list_del_init(&root_log_ctx.list);
3243 mutex_unlock(&log_root_tree->log_mutex);
3244 ret = root_log_ctx.log_ret;
3248 index2 = root_log_ctx.log_transid % 2;
3249 if (atomic_read(&log_root_tree->log_commit[index2])) {
3250 blk_finish_plug(&plug);
3251 ret = btrfs_wait_tree_log_extents(log, mark);
3252 wait_log_commit(log_root_tree,
3253 root_log_ctx.log_transid);
3254 mutex_unlock(&log_root_tree->log_mutex);
3256 ret = root_log_ctx.log_ret;
3259 ASSERT(root_log_ctx.log_transid == log_root_tree->log_transid);
3260 atomic_set(&log_root_tree->log_commit[index2], 1);
3262 if (atomic_read(&log_root_tree->log_commit[(index2 + 1) % 2])) {
3263 wait_log_commit(log_root_tree,
3264 root_log_ctx.log_transid - 1);
3268 * now that we've moved on to the tree of log tree roots,
3269 * check the full commit flag again
3271 if (btrfs_need_log_full_commit(trans)) {
3272 blk_finish_plug(&plug);
3273 btrfs_wait_tree_log_extents(log, mark);
3274 mutex_unlock(&log_root_tree->log_mutex);
3276 goto out_wake_log_root;
3279 ret = btrfs_write_marked_extents(fs_info,
3280 &log_root_tree->dirty_log_pages,
3281 EXTENT_DIRTY | EXTENT_NEW);
3282 blk_finish_plug(&plug);
3284 * As described above, -EAGAIN indicates a hole in the extents. We
3285 * cannot wait for these write outs since the waiting cause a
3286 * deadlock. Bail out to the full commit instead.
3288 if (ret == -EAGAIN && btrfs_is_zoned(fs_info)) {
3289 btrfs_set_log_full_commit(trans);
3290 btrfs_wait_tree_log_extents(log, mark);
3291 mutex_unlock(&log_root_tree->log_mutex);
3292 goto out_wake_log_root;
3294 btrfs_set_log_full_commit(trans);
3295 btrfs_abort_transaction(trans, ret);
3296 mutex_unlock(&log_root_tree->log_mutex);
3297 goto out_wake_log_root;
3299 ret = btrfs_wait_tree_log_extents(log, mark);
3301 ret = btrfs_wait_tree_log_extents(log_root_tree,
3302 EXTENT_NEW | EXTENT_DIRTY);
3304 btrfs_set_log_full_commit(trans);
3305 mutex_unlock(&log_root_tree->log_mutex);
3306 goto out_wake_log_root;
3309 log_root_start = log_root_tree->node->start;
3310 log_root_level = btrfs_header_level(log_root_tree->node);
3311 log_root_tree->log_transid++;
3312 mutex_unlock(&log_root_tree->log_mutex);
3315 * Here we are guaranteed that nobody is going to write the superblock
3316 * for the current transaction before us and that neither we do write
3317 * our superblock before the previous transaction finishes its commit
3318 * and writes its superblock, because:
3320 * 1) We are holding a handle on the current transaction, so no body
3321 * can commit it until we release the handle;
3323 * 2) Before writing our superblock we acquire the tree_log_mutex, so
3324 * if the previous transaction is still committing, and hasn't yet
3325 * written its superblock, we wait for it to do it, because a
3326 * transaction commit acquires the tree_log_mutex when the commit
3327 * begins and releases it only after writing its superblock.
3329 mutex_lock(&fs_info->tree_log_mutex);
3332 * The previous transaction writeout phase could have failed, and thus
3333 * marked the fs in an error state. We must not commit here, as we
3334 * could have updated our generation in the super_for_commit and
3335 * writing the super here would result in transid mismatches. If there
3336 * is an error here just bail.
3338 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
3340 btrfs_set_log_full_commit(trans);
3341 btrfs_abort_transaction(trans, ret);
3342 mutex_unlock(&fs_info->tree_log_mutex);
3343 goto out_wake_log_root;
3346 btrfs_set_super_log_root(fs_info->super_for_commit, log_root_start);
3347 btrfs_set_super_log_root_level(fs_info->super_for_commit, log_root_level);
3348 ret = write_all_supers(fs_info, 1);
3349 mutex_unlock(&fs_info->tree_log_mutex);
3351 btrfs_set_log_full_commit(trans);
3352 btrfs_abort_transaction(trans, ret);
3353 goto out_wake_log_root;
3357 * We know there can only be one task here, since we have not yet set
3358 * root->log_commit[index1] to 0 and any task attempting to sync the
3359 * log must wait for the previous log transaction to commit if it's
3360 * still in progress or wait for the current log transaction commit if
3361 * someone else already started it. We use <= and not < because the
3362 * first log transaction has an ID of 0.
3364 ASSERT(root->last_log_commit <= log_transid);
3365 root->last_log_commit = log_transid;
3368 mutex_lock(&log_root_tree->log_mutex);
3369 btrfs_remove_all_log_ctxs(log_root_tree, index2, ret);
3371 log_root_tree->log_transid_committed++;
3372 atomic_set(&log_root_tree->log_commit[index2], 0);
3373 mutex_unlock(&log_root_tree->log_mutex);
3376 * The barrier before waitqueue_active (in cond_wake_up) is needed so
3377 * all the updates above are seen by the woken threads. It might not be
3378 * necessary, but proving that seems to be hard.
3380 cond_wake_up(&log_root_tree->log_commit_wait[index2]);
3382 mutex_lock(&root->log_mutex);
3383 btrfs_remove_all_log_ctxs(root, index1, ret);
3384 root->log_transid_committed++;
3385 atomic_set(&root->log_commit[index1], 0);
3386 mutex_unlock(&root->log_mutex);
3389 * The barrier before waitqueue_active (in cond_wake_up) is needed so
3390 * all the updates above are seen by the woken threads. It might not be
3391 * necessary, but proving that seems to be hard.
3393 cond_wake_up(&root->log_commit_wait[index1]);
3397 static void free_log_tree(struct btrfs_trans_handle *trans,
3398 struct btrfs_root *log)
3401 struct walk_control wc = {
3403 .process_func = process_one_buffer
3407 ret = walk_log_tree(trans, log, &wc);
3410 * We weren't able to traverse the entire log tree, the
3411 * typical scenario is getting an -EIO when reading an
3412 * extent buffer of the tree, due to a previous writeback
3415 set_bit(BTRFS_FS_STATE_LOG_CLEANUP_ERROR,
3416 &log->fs_info->fs_state);
3419 * Some extent buffers of the log tree may still be dirty
3420 * and not yet written back to storage, because we may
3421 * have updates to a log tree without syncing a log tree,
3422 * such as during rename and link operations. So flush
3423 * them out and wait for their writeback to complete, so
3424 * that we properly cleanup their state and pages.
3426 btrfs_write_marked_extents(log->fs_info,
3427 &log->dirty_log_pages,
3428 EXTENT_DIRTY | EXTENT_NEW);
3429 btrfs_wait_tree_log_extents(log,
3430 EXTENT_DIRTY | EXTENT_NEW);
3433 btrfs_abort_transaction(trans, ret);
3435 btrfs_handle_fs_error(log->fs_info, ret, NULL);
3439 clear_extent_bits(&log->dirty_log_pages, 0, (u64)-1,
3440 EXTENT_DIRTY | EXTENT_NEW | EXTENT_NEED_WAIT);
3441 extent_io_tree_release(&log->log_csum_range);
3443 btrfs_put_root(log);
3447 * free all the extents used by the tree log. This should be called
3448 * at commit time of the full transaction
3450 int btrfs_free_log(struct btrfs_trans_handle *trans, struct btrfs_root *root)
3452 if (root->log_root) {
3453 free_log_tree(trans, root->log_root);
3454 root->log_root = NULL;
3455 clear_bit(BTRFS_ROOT_HAS_LOG_TREE, &root->state);
3460 int btrfs_free_log_root_tree(struct btrfs_trans_handle *trans,
3461 struct btrfs_fs_info *fs_info)
3463 if (fs_info->log_root_tree) {
3464 free_log_tree(trans, fs_info->log_root_tree);
3465 fs_info->log_root_tree = NULL;
3466 clear_bit(BTRFS_ROOT_HAS_LOG_TREE, &fs_info->tree_root->state);
3472 * Check if an inode was logged in the current transaction. This may often
3473 * return some false positives, because logged_trans is an in memory only field,
3474 * not persisted anywhere. This is meant to be used in contexts where a false
3475 * positive has no functional consequences.
3477 static bool inode_logged(struct btrfs_trans_handle *trans,
3478 struct btrfs_inode *inode)
3480 if (inode->logged_trans == trans->transid)
3484 * The inode's logged_trans is always 0 when we load it (because it is
3485 * not persisted in the inode item or elsewhere). So if it is 0, the
3486 * inode was last modified in the current transaction then the inode may
3487 * have been logged before in the current transaction, then evicted and
3488 * loaded again in the current transaction - or may have never been logged
3489 * in the current transaction, but since we can not be sure, we have to
3490 * assume it was, otherwise our callers can leave an inconsistent log.
3492 if (inode->logged_trans == 0 &&
3493 inode->last_trans == trans->transid &&
3494 !test_bit(BTRFS_FS_LOG_RECOVERING, &trans->fs_info->flags))
3501 * If both a file and directory are logged, and unlinks or renames are
3502 * mixed in, we have a few interesting corners:
3504 * create file X in dir Y
3505 * link file X to X.link in dir Y
3507 * unlink file X but leave X.link
3510 * After a crash we would expect only X.link to exist. But file X
3511 * didn't get fsync'd again so the log has back refs for X and X.link.
3513 * We solve this by removing directory entries and inode backrefs from the
3514 * log when a file that was logged in the current transaction is
3515 * unlinked. Any later fsync will include the updated log entries, and
3516 * we'll be able to reconstruct the proper directory items from backrefs.
3518 * This optimizations allows us to avoid relogging the entire inode
3519 * or the entire directory.
3521 int btrfs_del_dir_entries_in_log(struct btrfs_trans_handle *trans,
3522 struct btrfs_root *root,
3523 const char *name, int name_len,
3524 struct btrfs_inode *dir, u64 index)
3526 struct btrfs_root *log;
3527 struct btrfs_dir_item *di;
3528 struct btrfs_path *path;
3531 u64 dir_ino = btrfs_ino(dir);
3533 if (!inode_logged(trans, dir))
3536 ret = join_running_log_trans(root);
3540 mutex_lock(&dir->log_mutex);
3542 log = root->log_root;
3543 path = btrfs_alloc_path();
3549 di = btrfs_lookup_dir_item(trans, log, path, dir_ino,
3550 name, name_len, -1);
3556 ret = btrfs_delete_one_dir_name(trans, log, path, di);
3562 btrfs_release_path(path);
3563 di = btrfs_lookup_dir_index_item(trans, log, path, dir_ino,
3564 index, name, name_len, -1);
3570 ret = btrfs_delete_one_dir_name(trans, log, path, di);
3578 * We do not need to update the size field of the directory's inode item
3579 * because on log replay we update the field to reflect all existing
3580 * entries in the directory (see overwrite_item()).
3583 btrfs_free_path(path);
3585 mutex_unlock(&dir->log_mutex);
3586 if (err == -ENOSPC) {
3587 btrfs_set_log_full_commit(trans);
3589 } else if (err < 0) {
3590 btrfs_abort_transaction(trans, err);
3593 btrfs_end_log_trans(root);
3598 /* see comments for btrfs_del_dir_entries_in_log */
3599 int btrfs_del_inode_ref_in_log(struct btrfs_trans_handle *trans,
3600 struct btrfs_root *root,
3601 const char *name, int name_len,
3602 struct btrfs_inode *inode, u64 dirid)
3604 struct btrfs_root *log;
3608 if (!inode_logged(trans, inode))
3611 ret = join_running_log_trans(root);
3614 log = root->log_root;
3615 mutex_lock(&inode->log_mutex);
3617 ret = btrfs_del_inode_ref(trans, log, name, name_len, btrfs_ino(inode),
3619 mutex_unlock(&inode->log_mutex);
3620 if (ret == -ENOSPC) {
3621 btrfs_set_log_full_commit(trans);
3623 } else if (ret < 0 && ret != -ENOENT)
3624 btrfs_abort_transaction(trans, ret);
3625 btrfs_end_log_trans(root);
3631 * creates a range item in the log for 'dirid'. first_offset and
3632 * last_offset tell us which parts of the key space the log should
3633 * be considered authoritative for.
3635 static noinline int insert_dir_log_key(struct btrfs_trans_handle *trans,
3636 struct btrfs_root *log,
3637 struct btrfs_path *path,
3638 int key_type, u64 dirid,
3639 u64 first_offset, u64 last_offset)
3642 struct btrfs_key key;
3643 struct btrfs_dir_log_item *item;
3645 key.objectid = dirid;
3646 key.offset = first_offset;
3647 if (key_type == BTRFS_DIR_ITEM_KEY)
3648 key.type = BTRFS_DIR_LOG_ITEM_KEY;
3650 key.type = BTRFS_DIR_LOG_INDEX_KEY;
3651 ret = btrfs_insert_empty_item(trans, log, path, &key, sizeof(*item));
3655 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
3656 struct btrfs_dir_log_item);
3657 btrfs_set_dir_log_end(path->nodes[0], item, last_offset);
3658 btrfs_mark_buffer_dirty(path->nodes[0]);
3659 btrfs_release_path(path);
3664 * log all the items included in the current transaction for a given
3665 * directory. This also creates the range items in the log tree required
3666 * to replay anything deleted before the fsync
3668 static noinline int log_dir_items(struct btrfs_trans_handle *trans,
3669 struct btrfs_root *root, struct btrfs_inode *inode,
3670 struct btrfs_path *path,
3671 struct btrfs_path *dst_path, int key_type,
3672 struct btrfs_log_ctx *ctx,
3673 u64 min_offset, u64 *last_offset_ret)
3675 struct btrfs_key min_key;
3676 struct btrfs_root *log = root->log_root;
3677 struct extent_buffer *src;
3682 u64 first_offset = min_offset;
3683 u64 last_offset = (u64)-1;
3684 u64 ino = btrfs_ino(inode);
3686 log = root->log_root;
3688 min_key.objectid = ino;
3689 min_key.type = key_type;
3690 min_key.offset = min_offset;
3692 ret = btrfs_search_forward(root, &min_key, path, trans->transid);
3695 * we didn't find anything from this transaction, see if there
3696 * is anything at all
3698 if (ret != 0 || min_key.objectid != ino || min_key.type != key_type) {
3699 min_key.objectid = ino;
3700 min_key.type = key_type;
3701 min_key.offset = (u64)-1;
3702 btrfs_release_path(path);
3703 ret = btrfs_search_slot(NULL, root, &min_key, path, 0, 0);
3705 btrfs_release_path(path);
3708 ret = btrfs_previous_item(root, path, ino, key_type);
3710 /* if ret == 0 there are items for this type,
3711 * create a range to tell us the last key of this type.
3712 * otherwise, there are no items in this directory after
3713 * *min_offset, and we create a range to indicate that.
3716 struct btrfs_key tmp;
3717 btrfs_item_key_to_cpu(path->nodes[0], &tmp,
3719 if (key_type == tmp.type)
3720 first_offset = max(min_offset, tmp.offset) + 1;
3725 /* go backward to find any previous key */
3726 ret = btrfs_previous_item(root, path, ino, key_type);
3728 struct btrfs_key tmp;
3729 btrfs_item_key_to_cpu(path->nodes[0], &tmp, path->slots[0]);
3730 if (key_type == tmp.type) {
3731 first_offset = tmp.offset;
3732 ret = overwrite_item(trans, log, dst_path,
3733 path->nodes[0], path->slots[0],
3741 btrfs_release_path(path);
3744 * Find the first key from this transaction again. See the note for
3745 * log_new_dir_dentries, if we're logging a directory recursively we
3746 * won't be holding its i_mutex, which means we can modify the directory
3747 * while we're logging it. If we remove an entry between our first
3748 * search and this search we'll not find the key again and can just
3752 ret = btrfs_search_slot(NULL, root, &min_key, path, 0, 0);
3757 * we have a block from this transaction, log every item in it
3758 * from our directory
3761 struct btrfs_key tmp;
3762 src = path->nodes[0];
3763 nritems = btrfs_header_nritems(src);
3764 for (i = path->slots[0]; i < nritems; i++) {
3765 struct btrfs_dir_item *di;
3767 btrfs_item_key_to_cpu(src, &min_key, i);
3769 if (min_key.objectid != ino || min_key.type != key_type)
3772 if (need_resched()) {
3773 btrfs_release_path(path);
3778 ret = overwrite_item(trans, log, dst_path, src, i,
3786 * We must make sure that when we log a directory entry,
3787 * the corresponding inode, after log replay, has a
3788 * matching link count. For example:
3794 * xfs_io -c "fsync" mydir
3796 * <mount fs and log replay>
3798 * Would result in a fsync log that when replayed, our
3799 * file inode would have a link count of 1, but we get
3800 * two directory entries pointing to the same inode.
3801 * After removing one of the names, it would not be
3802 * possible to remove the other name, which resulted
3803 * always in stale file handle errors, and would not
3804 * be possible to rmdir the parent directory, since
3805 * its i_size could never decrement to the value
3806 * BTRFS_EMPTY_DIR_SIZE, resulting in -ENOTEMPTY errors.
3808 di = btrfs_item_ptr(src, i, struct btrfs_dir_item);
3809 btrfs_dir_item_key_to_cpu(src, di, &tmp);
3811 (btrfs_dir_transid(src, di) == trans->transid ||
3812 btrfs_dir_type(src, di) == BTRFS_FT_DIR) &&
3813 tmp.type != BTRFS_ROOT_ITEM_KEY)
3814 ctx->log_new_dentries = true;
3816 path->slots[0] = nritems;
3819 * look ahead to the next item and see if it is also
3820 * from this directory and from this transaction
3822 ret = btrfs_next_leaf(root, path);
3825 last_offset = (u64)-1;
3830 btrfs_item_key_to_cpu(path->nodes[0], &tmp, path->slots[0]);
3831 if (tmp.objectid != ino || tmp.type != key_type) {
3832 last_offset = (u64)-1;
3835 if (btrfs_header_generation(path->nodes[0]) != trans->transid) {
3836 ret = overwrite_item(trans, log, dst_path,
3837 path->nodes[0], path->slots[0],
3842 last_offset = tmp.offset;
3847 btrfs_release_path(path);
3848 btrfs_release_path(dst_path);
3851 *last_offset_ret = last_offset;
3853 * insert the log range keys to indicate where the log
3856 ret = insert_dir_log_key(trans, log, path, key_type,
3857 ino, first_offset, last_offset);
3865 * logging directories is very similar to logging inodes, We find all the items
3866 * from the current transaction and write them to the log.
3868 * The recovery code scans the directory in the subvolume, and if it finds a
3869 * key in the range logged that is not present in the log tree, then it means
3870 * that dir entry was unlinked during the transaction.
3872 * In order for that scan to work, we must include one key smaller than
3873 * the smallest logged by this transaction and one key larger than the largest
3874 * key logged by this transaction.
3876 static noinline int log_directory_changes(struct btrfs_trans_handle *trans,
3877 struct btrfs_root *root, struct btrfs_inode *inode,
3878 struct btrfs_path *path,
3879 struct btrfs_path *dst_path,
3880 struct btrfs_log_ctx *ctx)
3885 int key_type = BTRFS_DIR_ITEM_KEY;
3891 ret = log_dir_items(trans, root, inode, path, dst_path, key_type,
3892 ctx, min_key, &max_key);
3895 if (max_key == (u64)-1)
3897 min_key = max_key + 1;
3900 if (key_type == BTRFS_DIR_ITEM_KEY) {
3901 key_type = BTRFS_DIR_INDEX_KEY;
3908 * a helper function to drop items from the log before we relog an
3909 * inode. max_key_type indicates the highest item type to remove.
3910 * This cannot be run for file data extents because it does not
3911 * free the extents they point to.
3913 static int drop_objectid_items(struct btrfs_trans_handle *trans,
3914 struct btrfs_root *log,
3915 struct btrfs_path *path,
3916 u64 objectid, int max_key_type)
3919 struct btrfs_key key;
3920 struct btrfs_key found_key;
3923 key.objectid = objectid;
3924 key.type = max_key_type;
3925 key.offset = (u64)-1;
3928 ret = btrfs_search_slot(trans, log, &key, path, -1, 1);
3929 BUG_ON(ret == 0); /* Logic error */
3933 if (path->slots[0] == 0)
3937 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
3940 if (found_key.objectid != objectid)
3943 found_key.offset = 0;
3945 ret = btrfs_bin_search(path->nodes[0], &found_key, &start_slot);
3949 ret = btrfs_del_items(trans, log, path, start_slot,
3950 path->slots[0] - start_slot + 1);
3952 * If start slot isn't 0 then we don't need to re-search, we've
3953 * found the last guy with the objectid in this tree.
3955 if (ret || start_slot != 0)
3957 btrfs_release_path(path);
3959 btrfs_release_path(path);
3965 static void fill_inode_item(struct btrfs_trans_handle *trans,
3966 struct extent_buffer *leaf,
3967 struct btrfs_inode_item *item,
3968 struct inode *inode, int log_inode_only,
3971 struct btrfs_map_token token;
3974 btrfs_init_map_token(&token, leaf);
3976 if (log_inode_only) {
3977 /* set the generation to zero so the recover code
3978 * can tell the difference between an logging
3979 * just to say 'this inode exists' and a logging
3980 * to say 'update this inode with these values'
3982 btrfs_set_token_inode_generation(&token, item, 0);
3983 btrfs_set_token_inode_size(&token, item, logged_isize);
3985 btrfs_set_token_inode_generation(&token, item,
3986 BTRFS_I(inode)->generation);
3987 btrfs_set_token_inode_size(&token, item, inode->i_size);
3990 btrfs_set_token_inode_uid(&token, item, i_uid_read(inode));
3991 btrfs_set_token_inode_gid(&token, item, i_gid_read(inode));
3992 btrfs_set_token_inode_mode(&token, item, inode->i_mode);
3993 btrfs_set_token_inode_nlink(&token, item, inode->i_nlink);
3995 btrfs_set_token_timespec_sec(&token, &item->atime,
3996 inode->i_atime.tv_sec);
3997 btrfs_set_token_timespec_nsec(&token, &item->atime,
3998 inode->i_atime.tv_nsec);
4000 btrfs_set_token_timespec_sec(&token, &item->mtime,
4001 inode->i_mtime.tv_sec);
4002 btrfs_set_token_timespec_nsec(&token, &item->mtime,
4003 inode->i_mtime.tv_nsec);
4005 btrfs_set_token_timespec_sec(&token, &item->ctime,
4006 inode->i_ctime.tv_sec);
4007 btrfs_set_token_timespec_nsec(&token, &item->ctime,
4008 inode->i_ctime.tv_nsec);
4011 * We do not need to set the nbytes field, in fact during a fast fsync
4012 * its value may not even be correct, since a fast fsync does not wait
4013 * for ordered extent completion, which is where we update nbytes, it
4014 * only waits for writeback to complete. During log replay as we find
4015 * file extent items and replay them, we adjust the nbytes field of the
4016 * inode item in subvolume tree as needed (see overwrite_item()).
4019 btrfs_set_token_inode_sequence(&token, item, inode_peek_iversion(inode));
4020 btrfs_set_token_inode_transid(&token, item, trans->transid);
4021 btrfs_set_token_inode_rdev(&token, item, inode->i_rdev);
4022 flags = btrfs_inode_combine_flags(BTRFS_I(inode)->flags,
4023 BTRFS_I(inode)->ro_flags);
4024 btrfs_set_token_inode_flags(&token, item, flags);
4025 btrfs_set_token_inode_block_group(&token, item, 0);
4028 static int log_inode_item(struct btrfs_trans_handle *trans,
4029 struct btrfs_root *log, struct btrfs_path *path,
4030 struct btrfs_inode *inode, bool inode_item_dropped)
4032 struct btrfs_inode_item *inode_item;
4036 * If we are doing a fast fsync and the inode was logged before in the
4037 * current transaction, then we know the inode was previously logged and
4038 * it exists in the log tree. For performance reasons, in this case use
4039 * btrfs_search_slot() directly with ins_len set to 0 so that we never
4040 * attempt a write lock on the leaf's parent, which adds unnecessary lock
4041 * contention in case there are concurrent fsyncs for other inodes of the
4042 * same subvolume. Using btrfs_insert_empty_item() when the inode item
4043 * already exists can also result in unnecessarily splitting a leaf.
4045 if (!inode_item_dropped && inode->logged_trans == trans->transid) {
4046 ret = btrfs_search_slot(trans, log, &inode->location, path, 0, 1);
4052 * This means it is the first fsync in the current transaction,
4053 * so the inode item is not in the log and we need to insert it.
4054 * We can never get -EEXIST because we are only called for a fast
4055 * fsync and in case an inode eviction happens after the inode was
4056 * logged before in the current transaction, when we load again
4057 * the inode, we set BTRFS_INODE_NEEDS_FULL_SYNC on its runtime
4058 * flags and set ->logged_trans to 0.
4060 ret = btrfs_insert_empty_item(trans, log, path, &inode->location,
4061 sizeof(*inode_item));
4062 ASSERT(ret != -EEXIST);
4066 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
4067 struct btrfs_inode_item);
4068 fill_inode_item(trans, path->nodes[0], inode_item, &inode->vfs_inode,
4070 btrfs_release_path(path);
4074 static int log_csums(struct btrfs_trans_handle *trans,
4075 struct btrfs_inode *inode,
4076 struct btrfs_root *log_root,
4077 struct btrfs_ordered_sum *sums)
4079 const u64 lock_end = sums->bytenr + sums->len - 1;
4080 struct extent_state *cached_state = NULL;
4084 * If this inode was not used for reflink operations in the current
4085 * transaction with new extents, then do the fast path, no need to
4086 * worry about logging checksum items with overlapping ranges.
4088 if (inode->last_reflink_trans < trans->transid)
4089 return btrfs_csum_file_blocks(trans, log_root, sums);
4092 * Serialize logging for checksums. This is to avoid racing with the
4093 * same checksum being logged by another task that is logging another
4094 * file which happens to refer to the same extent as well. Such races
4095 * can leave checksum items in the log with overlapping ranges.
4097 ret = lock_extent_bits(&log_root->log_csum_range, sums->bytenr,
4098 lock_end, &cached_state);
4102 * Due to extent cloning, we might have logged a csum item that covers a
4103 * subrange of a cloned extent, and later we can end up logging a csum
4104 * item for a larger subrange of the same extent or the entire range.
4105 * This would leave csum items in the log tree that cover the same range
4106 * and break the searches for checksums in the log tree, resulting in
4107 * some checksums missing in the fs/subvolume tree. So just delete (or
4108 * trim and adjust) any existing csum items in the log for this range.
4110 ret = btrfs_del_csums(trans, log_root, sums->bytenr, sums->len);
4112 ret = btrfs_csum_file_blocks(trans, log_root, sums);
4114 unlock_extent_cached(&log_root->log_csum_range, sums->bytenr, lock_end,
4120 static noinline int copy_items(struct btrfs_trans_handle *trans,
4121 struct btrfs_inode *inode,
4122 struct btrfs_path *dst_path,
4123 struct btrfs_path *src_path,
4124 int start_slot, int nr, int inode_only,
4127 struct btrfs_fs_info *fs_info = trans->fs_info;
4128 unsigned long src_offset;
4129 unsigned long dst_offset;
4130 struct btrfs_root *log = inode->root->log_root;
4131 struct btrfs_file_extent_item *extent;
4132 struct btrfs_inode_item *inode_item;
4133 struct extent_buffer *src = src_path->nodes[0];
4135 struct btrfs_key *ins_keys;
4139 struct list_head ordered_sums;
4140 int skip_csum = inode->flags & BTRFS_INODE_NODATASUM;
4142 INIT_LIST_HEAD(&ordered_sums);
4144 ins_data = kmalloc(nr * sizeof(struct btrfs_key) +
4145 nr * sizeof(u32), GFP_NOFS);
4149 ins_sizes = (u32 *)ins_data;
4150 ins_keys = (struct btrfs_key *)(ins_data + nr * sizeof(u32));
4152 for (i = 0; i < nr; i++) {
4153 ins_sizes[i] = btrfs_item_size_nr(src, i + start_slot);
4154 btrfs_item_key_to_cpu(src, ins_keys + i, i + start_slot);
4156 ret = btrfs_insert_empty_items(trans, log, dst_path,
4157 ins_keys, ins_sizes, nr);
4163 for (i = 0; i < nr; i++, dst_path->slots[0]++) {
4164 dst_offset = btrfs_item_ptr_offset(dst_path->nodes[0],
4165 dst_path->slots[0]);
4167 src_offset = btrfs_item_ptr_offset(src, start_slot + i);
4169 if (ins_keys[i].type == BTRFS_INODE_ITEM_KEY) {
4170 inode_item = btrfs_item_ptr(dst_path->nodes[0],
4172 struct btrfs_inode_item);
4173 fill_inode_item(trans, dst_path->nodes[0], inode_item,
4175 inode_only == LOG_INODE_EXISTS,
4178 copy_extent_buffer(dst_path->nodes[0], src, dst_offset,
4179 src_offset, ins_sizes[i]);
4182 /* take a reference on file data extents so that truncates
4183 * or deletes of this inode don't have to relog the inode
4186 if (ins_keys[i].type == BTRFS_EXTENT_DATA_KEY &&
4189 extent = btrfs_item_ptr(src, start_slot + i,
4190 struct btrfs_file_extent_item);
4192 if (btrfs_file_extent_generation(src, extent) < trans->transid)
4195 found_type = btrfs_file_extent_type(src, extent);
4196 if (found_type == BTRFS_FILE_EXTENT_REG) {
4198 ds = btrfs_file_extent_disk_bytenr(src,
4200 /* ds == 0 is a hole */
4204 dl = btrfs_file_extent_disk_num_bytes(src,
4206 cs = btrfs_file_extent_offset(src, extent);
4207 cl = btrfs_file_extent_num_bytes(src,
4209 if (btrfs_file_extent_compression(src,
4215 ret = btrfs_lookup_csums_range(
4217 ds + cs, ds + cs + cl - 1,
4225 btrfs_mark_buffer_dirty(dst_path->nodes[0]);
4226 btrfs_release_path(dst_path);
4230 * we have to do this after the loop above to avoid changing the
4231 * log tree while trying to change the log tree.
4233 while (!list_empty(&ordered_sums)) {
4234 struct btrfs_ordered_sum *sums = list_entry(ordered_sums.next,
4235 struct btrfs_ordered_sum,
4238 ret = log_csums(trans, inode, log, sums);
4239 list_del(&sums->list);
4246 static int extent_cmp(void *priv, const struct list_head *a,
4247 const struct list_head *b)
4249 const struct extent_map *em1, *em2;
4251 em1 = list_entry(a, struct extent_map, list);
4252 em2 = list_entry(b, struct extent_map, list);
4254 if (em1->start < em2->start)
4256 else if (em1->start > em2->start)
4261 static int log_extent_csums(struct btrfs_trans_handle *trans,
4262 struct btrfs_inode *inode,
4263 struct btrfs_root *log_root,
4264 const struct extent_map *em,
4265 struct btrfs_log_ctx *ctx)
4267 struct btrfs_ordered_extent *ordered;
4270 u64 mod_start = em->mod_start;
4271 u64 mod_len = em->mod_len;
4272 LIST_HEAD(ordered_sums);
4275 if (inode->flags & BTRFS_INODE_NODATASUM ||
4276 test_bit(EXTENT_FLAG_PREALLOC, &em->flags) ||
4277 em->block_start == EXTENT_MAP_HOLE)
4280 list_for_each_entry(ordered, &ctx->ordered_extents, log_list) {
4281 const u64 ordered_end = ordered->file_offset + ordered->num_bytes;
4282 const u64 mod_end = mod_start + mod_len;
4283 struct btrfs_ordered_sum *sums;
4288 if (ordered_end <= mod_start)
4290 if (mod_end <= ordered->file_offset)
4294 * We are going to copy all the csums on this ordered extent, so
4295 * go ahead and adjust mod_start and mod_len in case this ordered
4296 * extent has already been logged.
4298 if (ordered->file_offset > mod_start) {
4299 if (ordered_end >= mod_end)
4300 mod_len = ordered->file_offset - mod_start;
4302 * If we have this case
4304 * |--------- logged extent ---------|
4305 * |----- ordered extent ----|
4307 * Just don't mess with mod_start and mod_len, we'll
4308 * just end up logging more csums than we need and it
4312 if (ordered_end < mod_end) {
4313 mod_len = mod_end - ordered_end;
4314 mod_start = ordered_end;
4321 * To keep us from looping for the above case of an ordered
4322 * extent that falls inside of the logged extent.
4324 if (test_and_set_bit(BTRFS_ORDERED_LOGGED_CSUM, &ordered->flags))
4327 list_for_each_entry(sums, &ordered->list, list) {
4328 ret = log_csums(trans, inode, log_root, sums);
4334 /* We're done, found all csums in the ordered extents. */
4338 /* If we're compressed we have to save the entire range of csums. */
4339 if (em->compress_type) {
4341 csum_len = max(em->block_len, em->orig_block_len);
4343 csum_offset = mod_start - em->start;
4347 /* block start is already adjusted for the file extent offset. */
4348 ret = btrfs_lookup_csums_range(trans->fs_info->csum_root,
4349 em->block_start + csum_offset,
4350 em->block_start + csum_offset +
4351 csum_len - 1, &ordered_sums, 0);
4355 while (!list_empty(&ordered_sums)) {
4356 struct btrfs_ordered_sum *sums = list_entry(ordered_sums.next,
4357 struct btrfs_ordered_sum,
4360 ret = log_csums(trans, inode, log_root, sums);
4361 list_del(&sums->list);
4368 static int log_one_extent(struct btrfs_trans_handle *trans,
4369 struct btrfs_inode *inode, struct btrfs_root *root,
4370 const struct extent_map *em,
4371 struct btrfs_path *path,
4372 struct btrfs_log_ctx *ctx)
4374 struct btrfs_drop_extents_args drop_args = { 0 };
4375 struct btrfs_root *log = root->log_root;
4376 struct btrfs_file_extent_item *fi;
4377 struct extent_buffer *leaf;
4378 struct btrfs_map_token token;
4379 struct btrfs_key key;
4380 u64 extent_offset = em->start - em->orig_start;
4384 ret = log_extent_csums(trans, inode, log, em, ctx);
4388 drop_args.path = path;
4389 drop_args.start = em->start;
4390 drop_args.end = em->start + em->len;
4391 drop_args.replace_extent = true;
4392 drop_args.extent_item_size = sizeof(*fi);
4393 ret = btrfs_drop_extents(trans, log, inode, &drop_args);
4397 if (!drop_args.extent_inserted) {
4398 key.objectid = btrfs_ino(inode);
4399 key.type = BTRFS_EXTENT_DATA_KEY;
4400 key.offset = em->start;
4402 ret = btrfs_insert_empty_item(trans, log, path, &key,
4407 leaf = path->nodes[0];
4408 btrfs_init_map_token(&token, leaf);
4409 fi = btrfs_item_ptr(leaf, path->slots[0],
4410 struct btrfs_file_extent_item);
4412 btrfs_set_token_file_extent_generation(&token, fi, trans->transid);
4413 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
4414 btrfs_set_token_file_extent_type(&token, fi,
4415 BTRFS_FILE_EXTENT_PREALLOC);
4417 btrfs_set_token_file_extent_type(&token, fi,
4418 BTRFS_FILE_EXTENT_REG);
4420 block_len = max(em->block_len, em->orig_block_len);
4421 if (em->compress_type != BTRFS_COMPRESS_NONE) {
4422 btrfs_set_token_file_extent_disk_bytenr(&token, fi,
4424 btrfs_set_token_file_extent_disk_num_bytes(&token, fi, block_len);
4425 } else if (em->block_start < EXTENT_MAP_LAST_BYTE) {
4426 btrfs_set_token_file_extent_disk_bytenr(&token, fi,
4429 btrfs_set_token_file_extent_disk_num_bytes(&token, fi, block_len);
4431 btrfs_set_token_file_extent_disk_bytenr(&token, fi, 0);
4432 btrfs_set_token_file_extent_disk_num_bytes(&token, fi, 0);
4435 btrfs_set_token_file_extent_offset(&token, fi, extent_offset);
4436 btrfs_set_token_file_extent_num_bytes(&token, fi, em->len);
4437 btrfs_set_token_file_extent_ram_bytes(&token, fi, em->ram_bytes);
4438 btrfs_set_token_file_extent_compression(&token, fi, em->compress_type);
4439 btrfs_set_token_file_extent_encryption(&token, fi, 0);
4440 btrfs_set_token_file_extent_other_encoding(&token, fi, 0);
4441 btrfs_mark_buffer_dirty(leaf);
4443 btrfs_release_path(path);
4449 * Log all prealloc extents beyond the inode's i_size to make sure we do not
4450 * lose them after doing a full/fast fsync and replaying the log. We scan the
4451 * subvolume's root instead of iterating the inode's extent map tree because
4452 * otherwise we can log incorrect extent items based on extent map conversion.
4453 * That can happen due to the fact that extent maps are merged when they
4454 * are not in the extent map tree's list of modified extents.
4456 static int btrfs_log_prealloc_extents(struct btrfs_trans_handle *trans,
4457 struct btrfs_inode *inode,
4458 struct btrfs_path *path)
4460 struct btrfs_root *root = inode->root;
4461 struct btrfs_key key;
4462 const u64 i_size = i_size_read(&inode->vfs_inode);
4463 const u64 ino = btrfs_ino(inode);
4464 struct btrfs_path *dst_path = NULL;
4465 bool dropped_extents = false;
4466 u64 truncate_offset = i_size;
4467 struct extent_buffer *leaf;
4473 if (!(inode->flags & BTRFS_INODE_PREALLOC))
4477 key.type = BTRFS_EXTENT_DATA_KEY;
4478 key.offset = i_size;
4479 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4484 * We must check if there is a prealloc extent that starts before the
4485 * i_size and crosses the i_size boundary. This is to ensure later we
4486 * truncate down to the end of that extent and not to the i_size, as
4487 * otherwise we end up losing part of the prealloc extent after a log
4488 * replay and with an implicit hole if there is another prealloc extent
4489 * that starts at an offset beyond i_size.
4491 ret = btrfs_previous_item(root, path, ino, BTRFS_EXTENT_DATA_KEY);
4496 struct btrfs_file_extent_item *ei;
4498 leaf = path->nodes[0];
4499 slot = path->slots[0];
4500 ei = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
4502 if (btrfs_file_extent_type(leaf, ei) ==
4503 BTRFS_FILE_EXTENT_PREALLOC) {
4506 btrfs_item_key_to_cpu(leaf, &key, slot);
4507 extent_end = key.offset +
4508 btrfs_file_extent_num_bytes(leaf, ei);
4510 if (extent_end > i_size)
4511 truncate_offset = extent_end;
4518 leaf = path->nodes[0];
4519 slot = path->slots[0];
4521 if (slot >= btrfs_header_nritems(leaf)) {
4523 ret = copy_items(trans, inode, dst_path, path,
4524 start_slot, ins_nr, 1, 0);
4529 ret = btrfs_next_leaf(root, path);
4539 btrfs_item_key_to_cpu(leaf, &key, slot);
4540 if (key.objectid > ino)
4542 if (WARN_ON_ONCE(key.objectid < ino) ||
4543 key.type < BTRFS_EXTENT_DATA_KEY ||
4544 key.offset < i_size) {
4548 if (!dropped_extents) {
4550 * Avoid logging extent items logged in past fsync calls
4551 * and leading to duplicate keys in the log tree.
4554 ret = btrfs_truncate_inode_items(trans,
4556 inode, truncate_offset,
4557 BTRFS_EXTENT_DATA_KEY,
4559 } while (ret == -EAGAIN);
4562 dropped_extents = true;
4569 dst_path = btrfs_alloc_path();
4577 ret = copy_items(trans, inode, dst_path, path,
4578 start_slot, ins_nr, 1, 0);
4580 btrfs_release_path(path);
4581 btrfs_free_path(dst_path);
4585 static int btrfs_log_changed_extents(struct btrfs_trans_handle *trans,
4586 struct btrfs_root *root,
4587 struct btrfs_inode *inode,
4588 struct btrfs_path *path,
4589 struct btrfs_log_ctx *ctx)
4591 struct btrfs_ordered_extent *ordered;
4592 struct btrfs_ordered_extent *tmp;
4593 struct extent_map *em, *n;
4594 struct list_head extents;
4595 struct extent_map_tree *tree = &inode->extent_tree;
4599 INIT_LIST_HEAD(&extents);
4601 write_lock(&tree->lock);
4603 list_for_each_entry_safe(em, n, &tree->modified_extents, list) {
4604 list_del_init(&em->list);
4606 * Just an arbitrary number, this can be really CPU intensive
4607 * once we start getting a lot of extents, and really once we
4608 * have a bunch of extents we just want to commit since it will
4611 if (++num > 32768) {
4612 list_del_init(&tree->modified_extents);
4617 if (em->generation < trans->transid)
4620 /* We log prealloc extents beyond eof later. */
4621 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) &&
4622 em->start >= i_size_read(&inode->vfs_inode))
4625 /* Need a ref to keep it from getting evicted from cache */
4626 refcount_inc(&em->refs);
4627 set_bit(EXTENT_FLAG_LOGGING, &em->flags);
4628 list_add_tail(&em->list, &extents);
4632 list_sort(NULL, &extents, extent_cmp);
4634 while (!list_empty(&extents)) {
4635 em = list_entry(extents.next, struct extent_map, list);
4637 list_del_init(&em->list);
4640 * If we had an error we just need to delete everybody from our
4644 clear_em_logging(tree, em);
4645 free_extent_map(em);
4649 write_unlock(&tree->lock);
4651 ret = log_one_extent(trans, inode, root, em, path, ctx);
4652 write_lock(&tree->lock);
4653 clear_em_logging(tree, em);
4654 free_extent_map(em);
4656 WARN_ON(!list_empty(&extents));
4657 write_unlock(&tree->lock);
4659 btrfs_release_path(path);
4661 ret = btrfs_log_prealloc_extents(trans, inode, path);
4666 * We have logged all extents successfully, now make sure the commit of
4667 * the current transaction waits for the ordered extents to complete
4668 * before it commits and wipes out the log trees, otherwise we would
4669 * lose data if an ordered extents completes after the transaction
4670 * commits and a power failure happens after the transaction commit.
4672 list_for_each_entry_safe(ordered, tmp, &ctx->ordered_extents, log_list) {
4673 list_del_init(&ordered->log_list);
4674 set_bit(BTRFS_ORDERED_LOGGED, &ordered->flags);
4676 if (!test_bit(BTRFS_ORDERED_COMPLETE, &ordered->flags)) {
4677 spin_lock_irq(&inode->ordered_tree.lock);
4678 if (!test_bit(BTRFS_ORDERED_COMPLETE, &ordered->flags)) {
4679 set_bit(BTRFS_ORDERED_PENDING, &ordered->flags);
4680 atomic_inc(&trans->transaction->pending_ordered);
4682 spin_unlock_irq(&inode->ordered_tree.lock);
4684 btrfs_put_ordered_extent(ordered);
4690 static int logged_inode_size(struct btrfs_root *log, struct btrfs_inode *inode,
4691 struct btrfs_path *path, u64 *size_ret)
4693 struct btrfs_key key;
4696 key.objectid = btrfs_ino(inode);
4697 key.type = BTRFS_INODE_ITEM_KEY;
4700 ret = btrfs_search_slot(NULL, log, &key, path, 0, 0);
4703 } else if (ret > 0) {
4706 struct btrfs_inode_item *item;
4708 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
4709 struct btrfs_inode_item);
4710 *size_ret = btrfs_inode_size(path->nodes[0], item);
4712 * If the in-memory inode's i_size is smaller then the inode
4713 * size stored in the btree, return the inode's i_size, so
4714 * that we get a correct inode size after replaying the log
4715 * when before a power failure we had a shrinking truncate
4716 * followed by addition of a new name (rename / new hard link).
4717 * Otherwise return the inode size from the btree, to avoid
4718 * data loss when replaying a log due to previously doing a
4719 * write that expands the inode's size and logging a new name
4720 * immediately after.
4722 if (*size_ret > inode->vfs_inode.i_size)
4723 *size_ret = inode->vfs_inode.i_size;
4726 btrfs_release_path(path);
4731 * At the moment we always log all xattrs. This is to figure out at log replay
4732 * time which xattrs must have their deletion replayed. If a xattr is missing
4733 * in the log tree and exists in the fs/subvol tree, we delete it. This is
4734 * because if a xattr is deleted, the inode is fsynced and a power failure
4735 * happens, causing the log to be replayed the next time the fs is mounted,
4736 * we want the xattr to not exist anymore (same behaviour as other filesystems
4737 * with a journal, ext3/4, xfs, f2fs, etc).
4739 static int btrfs_log_all_xattrs(struct btrfs_trans_handle *trans,
4740 struct btrfs_root *root,
4741 struct btrfs_inode *inode,
4742 struct btrfs_path *path,
4743 struct btrfs_path *dst_path)
4746 struct btrfs_key key;
4747 const u64 ino = btrfs_ino(inode);
4750 bool found_xattrs = false;
4752 if (test_bit(BTRFS_INODE_NO_XATTRS, &inode->runtime_flags))
4756 key.type = BTRFS_XATTR_ITEM_KEY;
4759 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4764 int slot = path->slots[0];
4765 struct extent_buffer *leaf = path->nodes[0];
4766 int nritems = btrfs_header_nritems(leaf);
4768 if (slot >= nritems) {
4770 ret = copy_items(trans, inode, dst_path, path,
4771 start_slot, ins_nr, 1, 0);
4776 ret = btrfs_next_leaf(root, path);
4784 btrfs_item_key_to_cpu(leaf, &key, slot);
4785 if (key.objectid != ino || key.type != BTRFS_XATTR_ITEM_KEY)
4792 found_xattrs = true;
4796 ret = copy_items(trans, inode, dst_path, path,
4797 start_slot, ins_nr, 1, 0);
4803 set_bit(BTRFS_INODE_NO_XATTRS, &inode->runtime_flags);
4809 * When using the NO_HOLES feature if we punched a hole that causes the
4810 * deletion of entire leafs or all the extent items of the first leaf (the one
4811 * that contains the inode item and references) we may end up not processing
4812 * any extents, because there are no leafs with a generation matching the
4813 * current transaction that have extent items for our inode. So we need to find
4814 * if any holes exist and then log them. We also need to log holes after any
4815 * truncate operation that changes the inode's size.
4817 static int btrfs_log_holes(struct btrfs_trans_handle *trans,
4818 struct btrfs_root *root,
4819 struct btrfs_inode *inode,
4820 struct btrfs_path *path)
4822 struct btrfs_fs_info *fs_info = root->fs_info;
4823 struct btrfs_key key;
4824 const u64 ino = btrfs_ino(inode);
4825 const u64 i_size = i_size_read(&inode->vfs_inode);
4826 u64 prev_extent_end = 0;
4829 if (!btrfs_fs_incompat(fs_info, NO_HOLES) || i_size == 0)
4833 key.type = BTRFS_EXTENT_DATA_KEY;
4836 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4841 struct extent_buffer *leaf = path->nodes[0];
4843 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
4844 ret = btrfs_next_leaf(root, path);
4851 leaf = path->nodes[0];
4854 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
4855 if (key.objectid != ino || key.type != BTRFS_EXTENT_DATA_KEY)
4858 /* We have a hole, log it. */
4859 if (prev_extent_end < key.offset) {
4860 const u64 hole_len = key.offset - prev_extent_end;
4863 * Release the path to avoid deadlocks with other code
4864 * paths that search the root while holding locks on
4865 * leafs from the log root.
4867 btrfs_release_path(path);
4868 ret = btrfs_insert_file_extent(trans, root->log_root,
4869 ino, prev_extent_end, 0,
4870 0, hole_len, 0, hole_len,
4876 * Search for the same key again in the root. Since it's
4877 * an extent item and we are holding the inode lock, the
4878 * key must still exist. If it doesn't just emit warning
4879 * and return an error to fall back to a transaction
4882 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4885 if (WARN_ON(ret > 0))
4887 leaf = path->nodes[0];
4890 prev_extent_end = btrfs_file_extent_end(path);
4895 if (prev_extent_end < i_size) {
4898 btrfs_release_path(path);
4899 hole_len = ALIGN(i_size - prev_extent_end, fs_info->sectorsize);
4900 ret = btrfs_insert_file_extent(trans, root->log_root,
4901 ino, prev_extent_end, 0, 0,
4902 hole_len, 0, hole_len,
4912 * When we are logging a new inode X, check if it doesn't have a reference that
4913 * matches the reference from some other inode Y created in a past transaction
4914 * and that was renamed in the current transaction. If we don't do this, then at
4915 * log replay time we can lose inode Y (and all its files if it's a directory):
4918 * echo "hello world" > /mnt/x/foobar
4921 * mkdir /mnt/x # or touch /mnt/x
4922 * xfs_io -c fsync /mnt/x
4924 * mount fs, trigger log replay
4926 * After the log replay procedure, we would lose the first directory and all its
4927 * files (file foobar).
4928 * For the case where inode Y is not a directory we simply end up losing it:
4930 * echo "123" > /mnt/foo
4932 * mv /mnt/foo /mnt/bar
4933 * echo "abc" > /mnt/foo
4934 * xfs_io -c fsync /mnt/foo
4937 * We also need this for cases where a snapshot entry is replaced by some other
4938 * entry (file or directory) otherwise we end up with an unreplayable log due to
4939 * attempts to delete the snapshot entry (entry of type BTRFS_ROOT_ITEM_KEY) as
4940 * if it were a regular entry:
4943 * btrfs subvolume snapshot /mnt /mnt/x/snap
4944 * btrfs subvolume delete /mnt/x/snap
4947 * fsync /mnt/x or fsync some new file inside it
4950 * The snapshot delete, rmdir of x, mkdir of a new x and the fsync all happen in
4951 * the same transaction.
4953 static int btrfs_check_ref_name_override(struct extent_buffer *eb,
4955 const struct btrfs_key *key,
4956 struct btrfs_inode *inode,
4957 u64 *other_ino, u64 *other_parent)
4960 struct btrfs_path *search_path;
4963 u32 item_size = btrfs_item_size_nr(eb, slot);
4965 unsigned long ptr = btrfs_item_ptr_offset(eb, slot);
4967 search_path = btrfs_alloc_path();
4970 search_path->search_commit_root = 1;
4971 search_path->skip_locking = 1;
4973 while (cur_offset < item_size) {
4977 unsigned long name_ptr;
4978 struct btrfs_dir_item *di;
4980 if (key->type == BTRFS_INODE_REF_KEY) {
4981 struct btrfs_inode_ref *iref;
4983 iref = (struct btrfs_inode_ref *)(ptr + cur_offset);
4984 parent = key->offset;
4985 this_name_len = btrfs_inode_ref_name_len(eb, iref);
4986 name_ptr = (unsigned long)(iref + 1);
4987 this_len = sizeof(*iref) + this_name_len;
4989 struct btrfs_inode_extref *extref;
4991 extref = (struct btrfs_inode_extref *)(ptr +
4993 parent = btrfs_inode_extref_parent(eb, extref);
4994 this_name_len = btrfs_inode_extref_name_len(eb, extref);
4995 name_ptr = (unsigned long)&extref->name;
4996 this_len = sizeof(*extref) + this_name_len;
4999 if (this_name_len > name_len) {
5002 new_name = krealloc(name, this_name_len, GFP_NOFS);
5007 name_len = this_name_len;
5011 read_extent_buffer(eb, name, name_ptr, this_name_len);
5012 di = btrfs_lookup_dir_item(NULL, inode->root, search_path,
5013 parent, name, this_name_len, 0);
5014 if (di && !IS_ERR(di)) {
5015 struct btrfs_key di_key;
5017 btrfs_dir_item_key_to_cpu(search_path->nodes[0],
5019 if (di_key.type == BTRFS_INODE_ITEM_KEY) {
5020 if (di_key.objectid != key->objectid) {
5022 *other_ino = di_key.objectid;
5023 *other_parent = parent;
5031 } else if (IS_ERR(di)) {
5035 btrfs_release_path(search_path);
5037 cur_offset += this_len;
5041 btrfs_free_path(search_path);
5046 struct btrfs_ino_list {
5049 struct list_head list;
5052 static int log_conflicting_inodes(struct btrfs_trans_handle *trans,
5053 struct btrfs_root *root,
5054 struct btrfs_path *path,
5055 struct btrfs_log_ctx *ctx,
5056 u64 ino, u64 parent)
5058 struct btrfs_ino_list *ino_elem;
5059 LIST_HEAD(inode_list);
5062 ino_elem = kmalloc(sizeof(*ino_elem), GFP_NOFS);
5065 ino_elem->ino = ino;
5066 ino_elem->parent = parent;
5067 list_add_tail(&ino_elem->list, &inode_list);
5069 while (!list_empty(&inode_list)) {
5070 struct btrfs_fs_info *fs_info = root->fs_info;
5071 struct btrfs_key key;
5072 struct inode *inode;
5074 ino_elem = list_first_entry(&inode_list, struct btrfs_ino_list,
5076 ino = ino_elem->ino;
5077 parent = ino_elem->parent;
5078 list_del(&ino_elem->list);
5083 btrfs_release_path(path);
5085 inode = btrfs_iget(fs_info->sb, ino, root);
5087 * If the other inode that had a conflicting dir entry was
5088 * deleted in the current transaction, we need to log its parent
5091 if (IS_ERR(inode)) {
5092 ret = PTR_ERR(inode);
5093 if (ret == -ENOENT) {
5094 inode = btrfs_iget(fs_info->sb, parent, root);
5095 if (IS_ERR(inode)) {
5096 ret = PTR_ERR(inode);
5098 ret = btrfs_log_inode(trans, root,
5100 LOG_OTHER_INODE_ALL,
5102 btrfs_add_delayed_iput(inode);
5108 * If the inode was already logged skip it - otherwise we can
5109 * hit an infinite loop. Example:
5111 * From the commit root (previous transaction) we have the
5114 * inode 257 a directory
5115 * inode 258 with references "zz" and "zz_link" on inode 257
5116 * inode 259 with reference "a" on inode 257
5118 * And in the current (uncommitted) transaction we have:
5120 * inode 257 a directory, unchanged
5121 * inode 258 with references "a" and "a2" on inode 257
5122 * inode 259 with reference "zz_link" on inode 257
5123 * inode 261 with reference "zz" on inode 257
5125 * When logging inode 261 the following infinite loop could
5126 * happen if we don't skip already logged inodes:
5128 * - we detect inode 258 as a conflicting inode, with inode 261
5129 * on reference "zz", and log it;
5131 * - we detect inode 259 as a conflicting inode, with inode 258
5132 * on reference "a", and log it;
5134 * - we detect inode 258 as a conflicting inode, with inode 259
5135 * on reference "zz_link", and log it - again! After this we
5136 * repeat the above steps forever.
5138 spin_lock(&BTRFS_I(inode)->lock);
5140 * Check the inode's logged_trans only instead of
5141 * btrfs_inode_in_log(). This is because the last_log_commit of
5142 * the inode is not updated when we only log that it exists (see
5143 * btrfs_log_inode()).
5145 if (BTRFS_I(inode)->logged_trans == trans->transid) {
5146 spin_unlock(&BTRFS_I(inode)->lock);
5147 btrfs_add_delayed_iput(inode);
5150 spin_unlock(&BTRFS_I(inode)->lock);
5152 * We are safe logging the other inode without acquiring its
5153 * lock as long as we log with the LOG_INODE_EXISTS mode. We
5154 * are safe against concurrent renames of the other inode as
5155 * well because during a rename we pin the log and update the
5156 * log with the new name before we unpin it.
5158 ret = btrfs_log_inode(trans, root, BTRFS_I(inode),
5159 LOG_OTHER_INODE, ctx);
5161 btrfs_add_delayed_iput(inode);
5166 key.type = BTRFS_INODE_REF_KEY;
5168 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5170 btrfs_add_delayed_iput(inode);
5175 struct extent_buffer *leaf = path->nodes[0];
5176 int slot = path->slots[0];
5178 u64 other_parent = 0;
5180 if (slot >= btrfs_header_nritems(leaf)) {
5181 ret = btrfs_next_leaf(root, path);
5184 } else if (ret > 0) {
5191 btrfs_item_key_to_cpu(leaf, &key, slot);
5192 if (key.objectid != ino ||
5193 (key.type != BTRFS_INODE_REF_KEY &&
5194 key.type != BTRFS_INODE_EXTREF_KEY)) {
5199 ret = btrfs_check_ref_name_override(leaf, slot, &key,
5200 BTRFS_I(inode), &other_ino,
5205 ino_elem = kmalloc(sizeof(*ino_elem), GFP_NOFS);
5210 ino_elem->ino = other_ino;
5211 ino_elem->parent = other_parent;
5212 list_add_tail(&ino_elem->list, &inode_list);
5217 btrfs_add_delayed_iput(inode);
5223 static int copy_inode_items_to_log(struct btrfs_trans_handle *trans,
5224 struct btrfs_inode *inode,
5225 struct btrfs_key *min_key,
5226 const struct btrfs_key *max_key,
5227 struct btrfs_path *path,
5228 struct btrfs_path *dst_path,
5229 const u64 logged_isize,
5230 const bool recursive_logging,
5231 const int inode_only,
5232 struct btrfs_log_ctx *ctx,
5233 bool *need_log_inode_item)
5235 const u64 i_size = i_size_read(&inode->vfs_inode);
5236 struct btrfs_root *root = inode->root;
5237 int ins_start_slot = 0;
5242 ret = btrfs_search_forward(root, min_key, path, trans->transid);
5250 /* Note, ins_nr might be > 0 here, cleanup outside the loop */
5251 if (min_key->objectid != max_key->objectid)
5253 if (min_key->type > max_key->type)
5256 if (min_key->type == BTRFS_INODE_ITEM_KEY) {
5257 *need_log_inode_item = false;
5258 } else if (min_key->type == BTRFS_EXTENT_DATA_KEY &&
5259 min_key->offset >= i_size) {
5261 * Extents at and beyond eof are logged with
5262 * btrfs_log_prealloc_extents().
5263 * Only regular files have BTRFS_EXTENT_DATA_KEY keys,
5264 * and no keys greater than that, so bail out.
5267 } else if ((min_key->type == BTRFS_INODE_REF_KEY ||
5268 min_key->type == BTRFS_INODE_EXTREF_KEY) &&
5269 inode->generation == trans->transid &&
5270 !recursive_logging) {
5272 u64 other_parent = 0;
5274 ret = btrfs_check_ref_name_override(path->nodes[0],
5275 path->slots[0], min_key, inode,
5276 &other_ino, &other_parent);
5279 } else if (ret > 0 && ctx &&
5280 other_ino != btrfs_ino(BTRFS_I(ctx->inode))) {
5285 ins_start_slot = path->slots[0];
5287 ret = copy_items(trans, inode, dst_path, path,
5288 ins_start_slot, ins_nr,
5289 inode_only, logged_isize);
5294 ret = log_conflicting_inodes(trans, root, path,
5295 ctx, other_ino, other_parent);
5298 btrfs_release_path(path);
5301 } else if (min_key->type == BTRFS_XATTR_ITEM_KEY) {
5302 /* Skip xattrs, logged later with btrfs_log_all_xattrs() */
5305 ret = copy_items(trans, inode, dst_path, path,
5307 ins_nr, inode_only, logged_isize);
5314 if (ins_nr && ins_start_slot + ins_nr == path->slots[0]) {
5317 } else if (!ins_nr) {
5318 ins_start_slot = path->slots[0];
5323 ret = copy_items(trans, inode, dst_path, path, ins_start_slot,
5324 ins_nr, inode_only, logged_isize);
5328 ins_start_slot = path->slots[0];
5331 if (path->slots[0] < btrfs_header_nritems(path->nodes[0])) {
5332 btrfs_item_key_to_cpu(path->nodes[0], min_key,
5337 ret = copy_items(trans, inode, dst_path, path,
5338 ins_start_slot, ins_nr, inode_only,
5344 btrfs_release_path(path);
5346 if (min_key->offset < (u64)-1) {
5348 } else if (min_key->type < max_key->type) {
5350 min_key->offset = 0;
5356 ret = copy_items(trans, inode, dst_path, path, ins_start_slot,
5357 ins_nr, inode_only, logged_isize);
5362 if (inode_only == LOG_INODE_ALL && S_ISREG(inode->vfs_inode.i_mode)) {
5364 * Release the path because otherwise we might attempt to double
5365 * lock the same leaf with btrfs_log_prealloc_extents() below.
5367 btrfs_release_path(path);
5368 ret = btrfs_log_prealloc_extents(trans, inode, dst_path);
5374 /* log a single inode in the tree log.
5375 * At least one parent directory for this inode must exist in the tree
5376 * or be logged already.
5378 * Any items from this inode changed by the current transaction are copied
5379 * to the log tree. An extra reference is taken on any extents in this
5380 * file, allowing us to avoid a whole pile of corner cases around logging
5381 * blocks that have been removed from the tree.
5383 * See LOG_INODE_ALL and related defines for a description of what inode_only
5386 * This handles both files and directories.
5388 static int btrfs_log_inode(struct btrfs_trans_handle *trans,
5389 struct btrfs_root *root, struct btrfs_inode *inode,
5391 struct btrfs_log_ctx *ctx)
5393 struct btrfs_path *path;
5394 struct btrfs_path *dst_path;
5395 struct btrfs_key min_key;
5396 struct btrfs_key max_key;
5397 struct btrfs_root *log = root->log_root;
5400 bool fast_search = false;
5401 u64 ino = btrfs_ino(inode);
5402 struct extent_map_tree *em_tree = &inode->extent_tree;
5403 u64 logged_isize = 0;
5404 bool need_log_inode_item = true;
5405 bool xattrs_logged = false;
5406 bool recursive_logging = false;
5407 bool inode_item_dropped = true;
5409 path = btrfs_alloc_path();
5412 dst_path = btrfs_alloc_path();
5414 btrfs_free_path(path);
5418 min_key.objectid = ino;
5419 min_key.type = BTRFS_INODE_ITEM_KEY;
5422 max_key.objectid = ino;
5425 /* today the code can only do partial logging of directories */
5426 if (S_ISDIR(inode->vfs_inode.i_mode) ||
5427 (!test_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
5428 &inode->runtime_flags) &&
5429 inode_only >= LOG_INODE_EXISTS))
5430 max_key.type = BTRFS_XATTR_ITEM_KEY;
5432 max_key.type = (u8)-1;
5433 max_key.offset = (u64)-1;
5436 * Only run delayed items if we are a directory. We want to make sure
5437 * all directory indexes hit the fs/subvolume tree so we can find them
5438 * and figure out which index ranges have to be logged.
5440 * Otherwise commit the delayed inode only if the full sync flag is set,
5441 * as we want to make sure an up to date version is in the subvolume
5442 * tree so copy_inode_items_to_log() / copy_items() can find it and copy
5443 * it to the log tree. For a non full sync, we always log the inode item
5444 * based on the in-memory struct btrfs_inode which is always up to date.
5446 if (S_ISDIR(inode->vfs_inode.i_mode))
5447 ret = btrfs_commit_inode_delayed_items(trans, inode);
5448 else if (test_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags))
5449 ret = btrfs_commit_inode_delayed_inode(inode);
5452 btrfs_free_path(path);
5453 btrfs_free_path(dst_path);
5457 if (inode_only == LOG_OTHER_INODE || inode_only == LOG_OTHER_INODE_ALL) {
5458 recursive_logging = true;
5459 if (inode_only == LOG_OTHER_INODE)
5460 inode_only = LOG_INODE_EXISTS;
5462 inode_only = LOG_INODE_ALL;
5463 mutex_lock_nested(&inode->log_mutex, SINGLE_DEPTH_NESTING);
5465 mutex_lock(&inode->log_mutex);
5469 * For symlinks, we must always log their content, which is stored in an
5470 * inline extent, otherwise we could end up with an empty symlink after
5471 * log replay, which is invalid on linux (symlink(2) returns -ENOENT if
5472 * one attempts to create an empty symlink).
5473 * We don't need to worry about flushing delalloc, because when we create
5474 * the inline extent when the symlink is created (we never have delalloc
5477 if (S_ISLNK(inode->vfs_inode.i_mode))
5478 inode_only = LOG_INODE_ALL;
5481 * This is for cases where logging a directory could result in losing a
5482 * a file after replaying the log. For example, if we move a file from a
5483 * directory A to a directory B, then fsync directory A, we have no way
5484 * to known the file was moved from A to B, so logging just A would
5485 * result in losing the file after a log replay.
5487 if (S_ISDIR(inode->vfs_inode.i_mode) &&
5488 inode_only == LOG_INODE_ALL &&
5489 inode->last_unlink_trans >= trans->transid) {
5490 btrfs_set_log_full_commit(trans);
5496 * a brute force approach to making sure we get the most uptodate
5497 * copies of everything.
5499 if (S_ISDIR(inode->vfs_inode.i_mode)) {
5500 int max_key_type = BTRFS_DIR_LOG_INDEX_KEY;
5502 clear_bit(BTRFS_INODE_COPY_EVERYTHING, &inode->runtime_flags);
5503 if (inode_only == LOG_INODE_EXISTS)
5504 max_key_type = BTRFS_XATTR_ITEM_KEY;
5505 ret = drop_objectid_items(trans, log, path, ino, max_key_type);
5507 if (inode_only == LOG_INODE_EXISTS) {
5509 * Make sure the new inode item we write to the log has
5510 * the same isize as the current one (if it exists).
5511 * This is necessary to prevent data loss after log
5512 * replay, and also to prevent doing a wrong expanding
5513 * truncate - for e.g. create file, write 4K into offset
5514 * 0, fsync, write 4K into offset 4096, add hard link,
5515 * fsync some other file (to sync log), power fail - if
5516 * we use the inode's current i_size, after log replay
5517 * we get a 8Kb file, with the last 4Kb extent as a hole
5518 * (zeroes), as if an expanding truncate happened,
5519 * instead of getting a file of 4Kb only.
5521 err = logged_inode_size(log, inode, path, &logged_isize);
5525 if (test_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
5526 &inode->runtime_flags)) {
5527 if (inode_only == LOG_INODE_EXISTS) {
5528 max_key.type = BTRFS_XATTR_ITEM_KEY;
5529 ret = drop_objectid_items(trans, log, path, ino,
5532 clear_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
5533 &inode->runtime_flags);
5534 clear_bit(BTRFS_INODE_COPY_EVERYTHING,
5535 &inode->runtime_flags);
5537 ret = btrfs_truncate_inode_items(trans,
5538 log, inode, 0, 0, NULL);
5543 } else if (test_and_clear_bit(BTRFS_INODE_COPY_EVERYTHING,
5544 &inode->runtime_flags) ||
5545 inode_only == LOG_INODE_EXISTS) {
5546 if (inode_only == LOG_INODE_ALL)
5548 max_key.type = BTRFS_XATTR_ITEM_KEY;
5549 ret = drop_objectid_items(trans, log, path, ino,
5552 if (inode_only == LOG_INODE_ALL)
5554 inode_item_dropped = false;
5564 err = copy_inode_items_to_log(trans, inode, &min_key, &max_key,
5565 path, dst_path, logged_isize,
5566 recursive_logging, inode_only, ctx,
5567 &need_log_inode_item);
5571 btrfs_release_path(path);
5572 btrfs_release_path(dst_path);
5573 err = btrfs_log_all_xattrs(trans, root, inode, path, dst_path);
5576 xattrs_logged = true;
5577 if (max_key.type >= BTRFS_EXTENT_DATA_KEY && !fast_search) {
5578 btrfs_release_path(path);
5579 btrfs_release_path(dst_path);
5580 err = btrfs_log_holes(trans, root, inode, path);
5585 btrfs_release_path(path);
5586 btrfs_release_path(dst_path);
5587 if (need_log_inode_item) {
5588 err = log_inode_item(trans, log, dst_path, inode, inode_item_dropped);
5592 * If we are doing a fast fsync and the inode was logged before
5593 * in this transaction, we don't need to log the xattrs because
5594 * they were logged before. If xattrs were added, changed or
5595 * deleted since the last time we logged the inode, then we have
5596 * already logged them because the inode had the runtime flag
5597 * BTRFS_INODE_COPY_EVERYTHING set.
5599 if (!xattrs_logged && inode->logged_trans < trans->transid) {
5600 err = btrfs_log_all_xattrs(trans, root, inode, path,
5604 btrfs_release_path(path);
5608 ret = btrfs_log_changed_extents(trans, root, inode, dst_path,
5614 } else if (inode_only == LOG_INODE_ALL) {
5615 struct extent_map *em, *n;
5617 write_lock(&em_tree->lock);
5618 list_for_each_entry_safe(em, n, &em_tree->modified_extents, list)
5619 list_del_init(&em->list);
5620 write_unlock(&em_tree->lock);
5623 if (inode_only == LOG_INODE_ALL && S_ISDIR(inode->vfs_inode.i_mode)) {
5624 ret = log_directory_changes(trans, root, inode, path, dst_path,
5633 * If we are logging that an ancestor inode exists as part of logging a
5634 * new name from a link or rename operation, don't mark the inode as
5635 * logged - otherwise if an explicit fsync is made against an ancestor,
5636 * the fsync considers the inode in the log and doesn't sync the log,
5637 * resulting in the ancestor missing after a power failure unless the
5638 * log was synced as part of an fsync against any other unrelated inode.
5639 * So keep it simple for this case and just don't flag the ancestors as
5643 !(S_ISDIR(inode->vfs_inode.i_mode) && ctx->logging_new_name &&
5644 &inode->vfs_inode != ctx->inode)) {
5645 spin_lock(&inode->lock);
5646 inode->logged_trans = trans->transid;
5648 * Don't update last_log_commit if we logged that an inode exists.
5649 * We do this for two reasons:
5651 * 1) We might have had buffered writes to this inode that were
5652 * flushed and had their ordered extents completed in this
5653 * transaction, but we did not previously log the inode with
5654 * LOG_INODE_ALL. Later the inode was evicted and after that
5655 * it was loaded again and this LOG_INODE_EXISTS log operation
5656 * happened. We must make sure that if an explicit fsync against
5657 * the inode is performed later, it logs the new extents, an
5658 * updated inode item, etc, and syncs the log. The same logic
5659 * applies to direct IO writes instead of buffered writes.
5661 * 2) When we log the inode with LOG_INODE_EXISTS, its inode item
5662 * is logged with an i_size of 0 or whatever value was logged
5663 * before. If later the i_size of the inode is increased by a
5664 * truncate operation, the log is synced through an fsync of
5665 * some other inode and then finally an explicit fsync against
5666 * this inode is made, we must make sure this fsync logs the
5667 * inode with the new i_size, the hole between old i_size and
5668 * the new i_size, and syncs the log.
5670 if (inode_only != LOG_INODE_EXISTS)
5671 inode->last_log_commit = inode->last_sub_trans;
5672 spin_unlock(&inode->lock);
5675 mutex_unlock(&inode->log_mutex);
5677 btrfs_free_path(path);
5678 btrfs_free_path(dst_path);
5683 * Check if we need to log an inode. This is used in contexts where while
5684 * logging an inode we need to log another inode (either that it exists or in
5685 * full mode). This is used instead of btrfs_inode_in_log() because the later
5686 * requires the inode to be in the log and have the log transaction committed,
5687 * while here we do not care if the log transaction was already committed - our
5688 * caller will commit the log later - and we want to avoid logging an inode
5689 * multiple times when multiple tasks have joined the same log transaction.
5691 static bool need_log_inode(struct btrfs_trans_handle *trans,
5692 struct btrfs_inode *inode)
5695 * If a directory was not modified, no dentries added or removed, we can
5696 * and should avoid logging it.
5698 if (S_ISDIR(inode->vfs_inode.i_mode) && inode->last_trans < trans->transid)
5702 * If this inode does not have new/updated/deleted xattrs since the last
5703 * time it was logged and is flagged as logged in the current transaction,
5704 * we can skip logging it. As for new/deleted names, those are updated in
5705 * the log by link/unlink/rename operations.
5706 * In case the inode was logged and then evicted and reloaded, its
5707 * logged_trans will be 0, in which case we have to fully log it since
5708 * logged_trans is a transient field, not persisted.
5710 if (inode->logged_trans == trans->transid &&
5711 !test_bit(BTRFS_INODE_COPY_EVERYTHING, &inode->runtime_flags))
5717 struct btrfs_dir_list {
5719 struct list_head list;
5723 * Log the inodes of the new dentries of a directory. See log_dir_items() for
5724 * details about the why it is needed.
5725 * This is a recursive operation - if an existing dentry corresponds to a
5726 * directory, that directory's new entries are logged too (same behaviour as
5727 * ext3/4, xfs, f2fs, reiserfs, nilfs2). Note that when logging the inodes
5728 * the dentries point to we do not lock their i_mutex, otherwise lockdep
5729 * complains about the following circular lock dependency / possible deadlock:
5733 * lock(&type->i_mutex_dir_key#3/2);
5734 * lock(sb_internal#2);
5735 * lock(&type->i_mutex_dir_key#3/2);
5736 * lock(&sb->s_type->i_mutex_key#14);
5738 * Where sb_internal is the lock (a counter that works as a lock) acquired by
5739 * sb_start_intwrite() in btrfs_start_transaction().
5740 * Not locking i_mutex of the inodes is still safe because:
5742 * 1) For regular files we log with a mode of LOG_INODE_EXISTS. It's possible
5743 * that while logging the inode new references (names) are added or removed
5744 * from the inode, leaving the logged inode item with a link count that does
5745 * not match the number of logged inode reference items. This is fine because
5746 * at log replay time we compute the real number of links and correct the
5747 * link count in the inode item (see replay_one_buffer() and
5748 * link_to_fixup_dir());
5750 * 2) For directories we log with a mode of LOG_INODE_ALL. It's possible that
5751 * while logging the inode's items new items with keys BTRFS_DIR_ITEM_KEY and
5752 * BTRFS_DIR_INDEX_KEY are added to fs/subvol tree and the logged inode item
5753 * has a size that doesn't match the sum of the lengths of all the logged
5754 * names. This does not result in a problem because if a dir_item key is
5755 * logged but its matching dir_index key is not logged, at log replay time we
5756 * don't use it to replay the respective name (see replay_one_name()). On the
5757 * other hand if only the dir_index key ends up being logged, the respective
5758 * name is added to the fs/subvol tree with both the dir_item and dir_index
5759 * keys created (see replay_one_name()).
5760 * The directory's inode item with a wrong i_size is not a problem as well,
5761 * since we don't use it at log replay time to set the i_size in the inode
5762 * item of the fs/subvol tree (see overwrite_item()).
5764 static int log_new_dir_dentries(struct btrfs_trans_handle *trans,
5765 struct btrfs_root *root,
5766 struct btrfs_inode *start_inode,
5767 struct btrfs_log_ctx *ctx)
5769 struct btrfs_fs_info *fs_info = root->fs_info;
5770 struct btrfs_root *log = root->log_root;
5771 struct btrfs_path *path;
5772 LIST_HEAD(dir_list);
5773 struct btrfs_dir_list *dir_elem;
5776 path = btrfs_alloc_path();
5780 dir_elem = kmalloc(sizeof(*dir_elem), GFP_NOFS);
5782 btrfs_free_path(path);
5785 dir_elem->ino = btrfs_ino(start_inode);
5786 list_add_tail(&dir_elem->list, &dir_list);
5788 while (!list_empty(&dir_list)) {
5789 struct extent_buffer *leaf;
5790 struct btrfs_key min_key;
5794 dir_elem = list_first_entry(&dir_list, struct btrfs_dir_list,
5797 goto next_dir_inode;
5799 min_key.objectid = dir_elem->ino;
5800 min_key.type = BTRFS_DIR_ITEM_KEY;
5803 btrfs_release_path(path);
5804 ret = btrfs_search_forward(log, &min_key, path, trans->transid);
5806 goto next_dir_inode;
5807 } else if (ret > 0) {
5809 goto next_dir_inode;
5813 leaf = path->nodes[0];
5814 nritems = btrfs_header_nritems(leaf);
5815 for (i = path->slots[0]; i < nritems; i++) {
5816 struct btrfs_dir_item *di;
5817 struct btrfs_key di_key;
5818 struct inode *di_inode;
5819 struct btrfs_dir_list *new_dir_elem;
5820 int log_mode = LOG_INODE_EXISTS;
5823 btrfs_item_key_to_cpu(leaf, &min_key, i);
5824 if (min_key.objectid != dir_elem->ino ||
5825 min_key.type != BTRFS_DIR_ITEM_KEY)
5826 goto next_dir_inode;
5828 di = btrfs_item_ptr(leaf, i, struct btrfs_dir_item);
5829 type = btrfs_dir_type(leaf, di);
5830 if (btrfs_dir_transid(leaf, di) < trans->transid &&
5831 type != BTRFS_FT_DIR)
5833 btrfs_dir_item_key_to_cpu(leaf, di, &di_key);
5834 if (di_key.type == BTRFS_ROOT_ITEM_KEY)
5837 btrfs_release_path(path);
5838 di_inode = btrfs_iget(fs_info->sb, di_key.objectid, root);
5839 if (IS_ERR(di_inode)) {
5840 ret = PTR_ERR(di_inode);
5841 goto next_dir_inode;
5844 if (!need_log_inode(trans, BTRFS_I(di_inode))) {
5845 btrfs_add_delayed_iput(di_inode);
5849 ctx->log_new_dentries = false;
5850 if (type == BTRFS_FT_DIR)
5851 log_mode = LOG_INODE_ALL;
5852 ret = btrfs_log_inode(trans, root, BTRFS_I(di_inode),
5854 btrfs_add_delayed_iput(di_inode);
5856 goto next_dir_inode;
5857 if (ctx->log_new_dentries) {
5858 new_dir_elem = kmalloc(sizeof(*new_dir_elem),
5860 if (!new_dir_elem) {
5862 goto next_dir_inode;
5864 new_dir_elem->ino = di_key.objectid;
5865 list_add_tail(&new_dir_elem->list, &dir_list);
5870 ret = btrfs_next_leaf(log, path);
5872 goto next_dir_inode;
5873 } else if (ret > 0) {
5875 goto next_dir_inode;
5879 if (min_key.offset < (u64)-1) {
5884 list_del(&dir_elem->list);
5888 btrfs_free_path(path);
5892 static int btrfs_log_all_parents(struct btrfs_trans_handle *trans,
5893 struct btrfs_inode *inode,
5894 struct btrfs_log_ctx *ctx)
5896 struct btrfs_fs_info *fs_info = trans->fs_info;
5898 struct btrfs_path *path;
5899 struct btrfs_key key;
5900 struct btrfs_root *root = inode->root;
5901 const u64 ino = btrfs_ino(inode);
5903 path = btrfs_alloc_path();
5906 path->skip_locking = 1;
5907 path->search_commit_root = 1;
5910 key.type = BTRFS_INODE_REF_KEY;
5912 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5917 struct extent_buffer *leaf = path->nodes[0];
5918 int slot = path->slots[0];
5923 if (slot >= btrfs_header_nritems(leaf)) {
5924 ret = btrfs_next_leaf(root, path);
5932 btrfs_item_key_to_cpu(leaf, &key, slot);
5933 /* BTRFS_INODE_EXTREF_KEY is BTRFS_INODE_REF_KEY + 1 */
5934 if (key.objectid != ino || key.type > BTRFS_INODE_EXTREF_KEY)
5937 item_size = btrfs_item_size_nr(leaf, slot);
5938 ptr = btrfs_item_ptr_offset(leaf, slot);
5939 while (cur_offset < item_size) {
5940 struct btrfs_key inode_key;
5941 struct inode *dir_inode;
5943 inode_key.type = BTRFS_INODE_ITEM_KEY;
5944 inode_key.offset = 0;
5946 if (key.type == BTRFS_INODE_EXTREF_KEY) {
5947 struct btrfs_inode_extref *extref;
5949 extref = (struct btrfs_inode_extref *)
5951 inode_key.objectid = btrfs_inode_extref_parent(
5953 cur_offset += sizeof(*extref);
5954 cur_offset += btrfs_inode_extref_name_len(leaf,
5957 inode_key.objectid = key.offset;
5958 cur_offset = item_size;
5961 dir_inode = btrfs_iget(fs_info->sb, inode_key.objectid,
5964 * If the parent inode was deleted, return an error to
5965 * fallback to a transaction commit. This is to prevent
5966 * getting an inode that was moved from one parent A to
5967 * a parent B, got its former parent A deleted and then
5968 * it got fsync'ed, from existing at both parents after
5969 * a log replay (and the old parent still existing).
5976 * mv /mnt/B/bar /mnt/A/bar
5977 * mv -T /mnt/A /mnt/B
5981 * If we ignore the old parent B which got deleted,
5982 * after a log replay we would have file bar linked
5983 * at both parents and the old parent B would still
5986 if (IS_ERR(dir_inode)) {
5987 ret = PTR_ERR(dir_inode);
5991 if (!need_log_inode(trans, BTRFS_I(dir_inode))) {
5992 btrfs_add_delayed_iput(dir_inode);
5997 ctx->log_new_dentries = false;
5998 ret = btrfs_log_inode(trans, root, BTRFS_I(dir_inode),
5999 LOG_INODE_ALL, ctx);
6000 if (!ret && ctx && ctx->log_new_dentries)
6001 ret = log_new_dir_dentries(trans, root,
6002 BTRFS_I(dir_inode), ctx);
6003 btrfs_add_delayed_iput(dir_inode);
6011 btrfs_free_path(path);
6015 static int log_new_ancestors(struct btrfs_trans_handle *trans,
6016 struct btrfs_root *root,
6017 struct btrfs_path *path,
6018 struct btrfs_log_ctx *ctx)
6020 struct btrfs_key found_key;
6022 btrfs_item_key_to_cpu(path->nodes[0], &found_key, path->slots[0]);
6025 struct btrfs_fs_info *fs_info = root->fs_info;
6026 struct extent_buffer *leaf = path->nodes[0];
6027 int slot = path->slots[0];
6028 struct btrfs_key search_key;
6029 struct inode *inode;
6033 btrfs_release_path(path);
6035 ino = found_key.offset;
6037 search_key.objectid = found_key.offset;
6038 search_key.type = BTRFS_INODE_ITEM_KEY;
6039 search_key.offset = 0;
6040 inode = btrfs_iget(fs_info->sb, ino, root);
6042 return PTR_ERR(inode);
6044 if (BTRFS_I(inode)->generation >= trans->transid &&
6045 need_log_inode(trans, BTRFS_I(inode)))
6046 ret = btrfs_log_inode(trans, root, BTRFS_I(inode),
6047 LOG_INODE_EXISTS, ctx);
6048 btrfs_add_delayed_iput(inode);
6052 if (search_key.objectid == BTRFS_FIRST_FREE_OBJECTID)
6055 search_key.type = BTRFS_INODE_REF_KEY;
6056 ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
6060 leaf = path->nodes[0];
6061 slot = path->slots[0];
6062 if (slot >= btrfs_header_nritems(leaf)) {
6063 ret = btrfs_next_leaf(root, path);
6068 leaf = path->nodes[0];
6069 slot = path->slots[0];
6072 btrfs_item_key_to_cpu(leaf, &found_key, slot);
6073 if (found_key.objectid != search_key.objectid ||
6074 found_key.type != BTRFS_INODE_REF_KEY)
6080 static int log_new_ancestors_fast(struct btrfs_trans_handle *trans,
6081 struct btrfs_inode *inode,
6082 struct dentry *parent,
6083 struct btrfs_log_ctx *ctx)
6085 struct btrfs_root *root = inode->root;
6086 struct dentry *old_parent = NULL;
6087 struct super_block *sb = inode->vfs_inode.i_sb;
6091 if (!parent || d_really_is_negative(parent) ||
6095 inode = BTRFS_I(d_inode(parent));
6096 if (root != inode->root)
6099 if (inode->generation >= trans->transid &&
6100 need_log_inode(trans, inode)) {
6101 ret = btrfs_log_inode(trans, root, inode,
6102 LOG_INODE_EXISTS, ctx);
6106 if (IS_ROOT(parent))
6109 parent = dget_parent(parent);
6111 old_parent = parent;
6118 static int log_all_new_ancestors(struct btrfs_trans_handle *trans,
6119 struct btrfs_inode *inode,
6120 struct dentry *parent,
6121 struct btrfs_log_ctx *ctx)
6123 struct btrfs_root *root = inode->root;
6124 const u64 ino = btrfs_ino(inode);
6125 struct btrfs_path *path;
6126 struct btrfs_key search_key;
6130 * For a single hard link case, go through a fast path that does not
6131 * need to iterate the fs/subvolume tree.
6133 if (inode->vfs_inode.i_nlink < 2)
6134 return log_new_ancestors_fast(trans, inode, parent, ctx);
6136 path = btrfs_alloc_path();
6140 search_key.objectid = ino;
6141 search_key.type = BTRFS_INODE_REF_KEY;
6142 search_key.offset = 0;
6144 ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
6151 struct extent_buffer *leaf = path->nodes[0];
6152 int slot = path->slots[0];
6153 struct btrfs_key found_key;
6155 if (slot >= btrfs_header_nritems(leaf)) {
6156 ret = btrfs_next_leaf(root, path);
6164 btrfs_item_key_to_cpu(leaf, &found_key, slot);
6165 if (found_key.objectid != ino ||
6166 found_key.type > BTRFS_INODE_EXTREF_KEY)
6170 * Don't deal with extended references because they are rare
6171 * cases and too complex to deal with (we would need to keep
6172 * track of which subitem we are processing for each item in
6173 * this loop, etc). So just return some error to fallback to
6174 * a transaction commit.
6176 if (found_key.type == BTRFS_INODE_EXTREF_KEY) {
6182 * Logging ancestors needs to do more searches on the fs/subvol
6183 * tree, so it releases the path as needed to avoid deadlocks.
6184 * Keep track of the last inode ref key and resume from that key
6185 * after logging all new ancestors for the current hard link.
6187 memcpy(&search_key, &found_key, sizeof(search_key));
6189 ret = log_new_ancestors(trans, root, path, ctx);
6192 btrfs_release_path(path);
6197 btrfs_free_path(path);
6202 * helper function around btrfs_log_inode to make sure newly created
6203 * parent directories also end up in the log. A minimal inode and backref
6204 * only logging is done of any parent directories that are older than
6205 * the last committed transaction
6207 static int btrfs_log_inode_parent(struct btrfs_trans_handle *trans,
6208 struct btrfs_inode *inode,
6209 struct dentry *parent,
6211 struct btrfs_log_ctx *ctx)
6213 struct btrfs_root *root = inode->root;
6214 struct btrfs_fs_info *fs_info = root->fs_info;
6216 bool log_dentries = false;
6218 if (btrfs_test_opt(fs_info, NOTREELOG)) {
6223 if (btrfs_root_refs(&root->root_item) == 0) {
6229 * Skip already logged inodes or inodes corresponding to tmpfiles
6230 * (since logging them is pointless, a link count of 0 means they
6231 * will never be accessible).
6233 if ((btrfs_inode_in_log(inode, trans->transid) &&
6234 list_empty(&ctx->ordered_extents)) ||
6235 inode->vfs_inode.i_nlink == 0) {
6236 ret = BTRFS_NO_LOG_SYNC;
6240 ret = start_log_trans(trans, root, ctx);
6244 ret = btrfs_log_inode(trans, root, inode, inode_only, ctx);
6249 * for regular files, if its inode is already on disk, we don't
6250 * have to worry about the parents at all. This is because
6251 * we can use the last_unlink_trans field to record renames
6252 * and other fun in this file.
6254 if (S_ISREG(inode->vfs_inode.i_mode) &&
6255 inode->generation < trans->transid &&
6256 inode->last_unlink_trans < trans->transid) {
6261 if (S_ISDIR(inode->vfs_inode.i_mode) && ctx && ctx->log_new_dentries)
6262 log_dentries = true;
6265 * On unlink we must make sure all our current and old parent directory
6266 * inodes are fully logged. This is to prevent leaving dangling
6267 * directory index entries in directories that were our parents but are
6268 * not anymore. Not doing this results in old parent directory being
6269 * impossible to delete after log replay (rmdir will always fail with
6270 * error -ENOTEMPTY).
6276 * ln testdir/foo testdir/bar
6278 * unlink testdir/bar
6279 * xfs_io -c fsync testdir/foo
6281 * mount fs, triggers log replay
6283 * If we don't log the parent directory (testdir), after log replay the
6284 * directory still has an entry pointing to the file inode using the bar
6285 * name, but a matching BTRFS_INODE_[REF|EXTREF]_KEY does not exist and
6286 * the file inode has a link count of 1.
6292 * ln foo testdir/foo2
6293 * ln foo testdir/foo3
6295 * unlink testdir/foo3
6296 * xfs_io -c fsync foo
6298 * mount fs, triggers log replay
6300 * Similar as the first example, after log replay the parent directory
6301 * testdir still has an entry pointing to the inode file with name foo3
6302 * but the file inode does not have a matching BTRFS_INODE_REF_KEY item
6303 * and has a link count of 2.
6305 if (inode->last_unlink_trans >= trans->transid) {
6306 ret = btrfs_log_all_parents(trans, inode, ctx);
6311 ret = log_all_new_ancestors(trans, inode, parent, ctx);
6316 ret = log_new_dir_dentries(trans, root, inode, ctx);
6321 btrfs_set_log_full_commit(trans);
6326 btrfs_remove_log_ctx(root, ctx);
6327 btrfs_end_log_trans(root);
6333 * it is not safe to log dentry if the chunk root has added new
6334 * chunks. This returns 0 if the dentry was logged, and 1 otherwise.
6335 * If this returns 1, you must commit the transaction to safely get your
6338 int btrfs_log_dentry_safe(struct btrfs_trans_handle *trans,
6339 struct dentry *dentry,
6340 struct btrfs_log_ctx *ctx)
6342 struct dentry *parent = dget_parent(dentry);
6345 ret = btrfs_log_inode_parent(trans, BTRFS_I(d_inode(dentry)), parent,
6346 LOG_INODE_ALL, ctx);
6353 * should be called during mount to recover any replay any log trees
6356 int btrfs_recover_log_trees(struct btrfs_root *log_root_tree)
6359 struct btrfs_path *path;
6360 struct btrfs_trans_handle *trans;
6361 struct btrfs_key key;
6362 struct btrfs_key found_key;
6363 struct btrfs_root *log;
6364 struct btrfs_fs_info *fs_info = log_root_tree->fs_info;
6365 struct walk_control wc = {
6366 .process_func = process_one_buffer,
6367 .stage = LOG_WALK_PIN_ONLY,
6370 path = btrfs_alloc_path();
6374 set_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags);
6376 trans = btrfs_start_transaction(fs_info->tree_root, 0);
6377 if (IS_ERR(trans)) {
6378 ret = PTR_ERR(trans);
6385 ret = walk_log_tree(trans, log_root_tree, &wc);
6387 btrfs_handle_fs_error(fs_info, ret,
6388 "Failed to pin buffers while recovering log root tree.");
6393 key.objectid = BTRFS_TREE_LOG_OBJECTID;
6394 key.offset = (u64)-1;
6395 key.type = BTRFS_ROOT_ITEM_KEY;
6398 ret = btrfs_search_slot(NULL, log_root_tree, &key, path, 0, 0);
6401 btrfs_handle_fs_error(fs_info, ret,
6402 "Couldn't find tree log root.");
6406 if (path->slots[0] == 0)
6410 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
6412 btrfs_release_path(path);
6413 if (found_key.objectid != BTRFS_TREE_LOG_OBJECTID)
6416 log = btrfs_read_tree_root(log_root_tree, &found_key);
6419 btrfs_handle_fs_error(fs_info, ret,
6420 "Couldn't read tree log root.");
6424 wc.replay_dest = btrfs_get_fs_root(fs_info, found_key.offset,
6426 if (IS_ERR(wc.replay_dest)) {
6427 ret = PTR_ERR(wc.replay_dest);
6430 * We didn't find the subvol, likely because it was
6431 * deleted. This is ok, simply skip this log and go to
6434 * We need to exclude the root because we can't have
6435 * other log replays overwriting this log as we'll read
6436 * it back in a few more times. This will keep our
6437 * block from being modified, and we'll just bail for
6438 * each subsequent pass.
6441 ret = btrfs_pin_extent_for_log_replay(trans,
6444 btrfs_put_root(log);
6448 btrfs_handle_fs_error(fs_info, ret,
6449 "Couldn't read target root for tree log recovery.");
6453 wc.replay_dest->log_root = log;
6454 ret = btrfs_record_root_in_trans(trans, wc.replay_dest);
6456 /* The loop needs to continue due to the root refs */
6457 btrfs_handle_fs_error(fs_info, ret,
6458 "failed to record the log root in transaction");
6460 ret = walk_log_tree(trans, log, &wc);
6462 if (!ret && wc.stage == LOG_WALK_REPLAY_ALL) {
6463 ret = fixup_inode_link_counts(trans, wc.replay_dest,
6467 if (!ret && wc.stage == LOG_WALK_REPLAY_ALL) {
6468 struct btrfs_root *root = wc.replay_dest;
6470 btrfs_release_path(path);
6473 * We have just replayed everything, and the highest
6474 * objectid of fs roots probably has changed in case
6475 * some inode_item's got replayed.
6477 * root->objectid_mutex is not acquired as log replay
6478 * could only happen during mount.
6480 ret = btrfs_init_root_free_objectid(root);
6483 wc.replay_dest->log_root = NULL;
6484 btrfs_put_root(wc.replay_dest);
6485 btrfs_put_root(log);
6490 if (found_key.offset == 0)
6492 key.offset = found_key.offset - 1;
6494 btrfs_release_path(path);
6496 /* step one is to pin it all, step two is to replay just inodes */
6499 wc.process_func = replay_one_buffer;
6500 wc.stage = LOG_WALK_REPLAY_INODES;
6503 /* step three is to replay everything */
6504 if (wc.stage < LOG_WALK_REPLAY_ALL) {
6509 btrfs_free_path(path);
6511 /* step 4: commit the transaction, which also unpins the blocks */
6512 ret = btrfs_commit_transaction(trans);
6516 log_root_tree->log_root = NULL;
6517 clear_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags);
6518 btrfs_put_root(log_root_tree);
6523 btrfs_end_transaction(wc.trans);
6524 clear_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags);
6525 btrfs_free_path(path);
6530 * there are some corner cases where we want to force a full
6531 * commit instead of allowing a directory to be logged.
6533 * They revolve around files there were unlinked from the directory, and
6534 * this function updates the parent directory so that a full commit is
6535 * properly done if it is fsync'd later after the unlinks are done.
6537 * Must be called before the unlink operations (updates to the subvolume tree,
6538 * inodes, etc) are done.
6540 void btrfs_record_unlink_dir(struct btrfs_trans_handle *trans,
6541 struct btrfs_inode *dir, struct btrfs_inode *inode,
6545 * when we're logging a file, if it hasn't been renamed
6546 * or unlinked, and its inode is fully committed on disk,
6547 * we don't have to worry about walking up the directory chain
6548 * to log its parents.
6550 * So, we use the last_unlink_trans field to put this transid
6551 * into the file. When the file is logged we check it and
6552 * don't log the parents if the file is fully on disk.
6554 mutex_lock(&inode->log_mutex);
6555 inode->last_unlink_trans = trans->transid;
6556 mutex_unlock(&inode->log_mutex);
6559 * if this directory was already logged any new
6560 * names for this file/dir will get recorded
6562 if (dir->logged_trans == trans->transid)
6566 * if the inode we're about to unlink was logged,
6567 * the log will be properly updated for any new names
6569 if (inode->logged_trans == trans->transid)
6573 * when renaming files across directories, if the directory
6574 * there we're unlinking from gets fsync'd later on, there's
6575 * no way to find the destination directory later and fsync it
6576 * properly. So, we have to be conservative and force commits
6577 * so the new name gets discovered.
6582 /* we can safely do the unlink without any special recording */
6586 mutex_lock(&dir->log_mutex);
6587 dir->last_unlink_trans = trans->transid;
6588 mutex_unlock(&dir->log_mutex);
6592 * Make sure that if someone attempts to fsync the parent directory of a deleted
6593 * snapshot, it ends up triggering a transaction commit. This is to guarantee
6594 * that after replaying the log tree of the parent directory's root we will not
6595 * see the snapshot anymore and at log replay time we will not see any log tree
6596 * corresponding to the deleted snapshot's root, which could lead to replaying
6597 * it after replaying the log tree of the parent directory (which would replay
6598 * the snapshot delete operation).
6600 * Must be called before the actual snapshot destroy operation (updates to the
6601 * parent root and tree of tree roots trees, etc) are done.
6603 void btrfs_record_snapshot_destroy(struct btrfs_trans_handle *trans,
6604 struct btrfs_inode *dir)
6606 mutex_lock(&dir->log_mutex);
6607 dir->last_unlink_trans = trans->transid;
6608 mutex_unlock(&dir->log_mutex);
6612 * Update the log after adding a new name for an inode.
6614 * @trans: Transaction handle.
6615 * @old_dentry: The dentry associated with the old name and the old
6617 * @old_dir: The inode of the previous parent directory for the case
6618 * of a rename. For a link operation, it must be NULL.
6619 * @parent: The dentry associated with the directory under which the
6620 * new name is located.
6622 * Call this after adding a new name for an inode, as a result of a link or
6623 * rename operation, and it will properly update the log to reflect the new name.
6625 void btrfs_log_new_name(struct btrfs_trans_handle *trans,
6626 struct dentry *old_dentry, struct btrfs_inode *old_dir,
6627 struct dentry *parent)
6629 struct btrfs_inode *inode = BTRFS_I(d_inode(old_dentry));
6630 struct btrfs_log_ctx ctx;
6633 * this will force the logging code to walk the dentry chain
6636 if (!S_ISDIR(inode->vfs_inode.i_mode))
6637 inode->last_unlink_trans = trans->transid;
6640 * if this inode hasn't been logged and directory we're renaming it
6641 * from hasn't been logged, we don't need to log it
6643 if (!inode_logged(trans, inode) &&
6644 (!old_dir || !inode_logged(trans, old_dir)))
6648 * If we are doing a rename (old_dir is not NULL) from a directory that
6649 * was previously logged, make sure the next log attempt on the directory
6650 * is not skipped and logs the inode again. This is because the log may
6651 * not currently be authoritative for a range including the old
6652 * BTRFS_DIR_ITEM_KEY and BTRFS_DIR_INDEX_KEY keys, so we want to make
6653 * sure after a log replay we do not end up with both the new and old
6654 * dentries around (in case the inode is a directory we would have a
6655 * directory with two hard links and 2 inode references for different
6656 * parents). The next log attempt of old_dir will happen at
6657 * btrfs_log_all_parents(), called through btrfs_log_inode_parent()
6658 * below, because we have previously set inode->last_unlink_trans to the
6659 * current transaction ID, either here or at btrfs_record_unlink_dir() in
6660 * case inode is a directory.
6663 old_dir->logged_trans = 0;
6665 btrfs_init_log_ctx(&ctx, &inode->vfs_inode);
6666 ctx.logging_new_name = true;
6668 * We don't care about the return value. If we fail to log the new name
6669 * then we know the next attempt to sync the log will fallback to a full
6670 * transaction commit (due to a call to btrfs_set_log_full_commit()), so
6671 * we don't need to worry about getting a log committed that has an
6672 * inconsistent state after a rename operation.
6674 btrfs_log_inode_parent(trans, inode, parent, LOG_INODE_EXISTS, &ctx);