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_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->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);
371 static int do_overwrite_item(struct btrfs_trans_handle *trans,
372 struct btrfs_root *root,
373 struct btrfs_path *path,
374 struct extent_buffer *eb, int slot,
375 struct btrfs_key *key)
379 u64 saved_i_size = 0;
380 int save_old_i_size = 0;
381 unsigned long src_ptr;
382 unsigned long dst_ptr;
383 int overwrite_root = 0;
384 bool inode_item = key->type == BTRFS_INODE_ITEM_KEY;
386 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID)
389 item_size = btrfs_item_size_nr(eb, slot);
390 src_ptr = btrfs_item_ptr_offset(eb, slot);
392 /* Our caller must have done a search for the key for us. */
393 ASSERT(path->nodes[0] != NULL);
396 * And the slot must point to the exact key or the slot where the key
397 * should be at (the first item with a key greater than 'key')
399 if (path->slots[0] < btrfs_header_nritems(path->nodes[0])) {
400 struct btrfs_key found_key;
402 btrfs_item_key_to_cpu(path->nodes[0], &found_key, path->slots[0]);
403 ret = btrfs_comp_cpu_keys(&found_key, key);
412 u32 dst_size = btrfs_item_size_nr(path->nodes[0],
414 if (dst_size != item_size)
417 if (item_size == 0) {
418 btrfs_release_path(path);
421 dst_copy = kmalloc(item_size, GFP_NOFS);
422 src_copy = kmalloc(item_size, GFP_NOFS);
423 if (!dst_copy || !src_copy) {
424 btrfs_release_path(path);
430 read_extent_buffer(eb, src_copy, src_ptr, item_size);
432 dst_ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
433 read_extent_buffer(path->nodes[0], dst_copy, dst_ptr,
435 ret = memcmp(dst_copy, src_copy, item_size);
440 * they have the same contents, just return, this saves
441 * us from cowing blocks in the destination tree and doing
442 * extra writes that may not have been done by a previous
446 btrfs_release_path(path);
451 * We need to load the old nbytes into the inode so when we
452 * replay the extents we've logged we get the right nbytes.
455 struct btrfs_inode_item *item;
459 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
460 struct btrfs_inode_item);
461 nbytes = btrfs_inode_nbytes(path->nodes[0], item);
462 item = btrfs_item_ptr(eb, slot,
463 struct btrfs_inode_item);
464 btrfs_set_inode_nbytes(eb, item, nbytes);
467 * If this is a directory we need to reset the i_size to
468 * 0 so that we can set it up properly when replaying
469 * the rest of the items in this log.
471 mode = btrfs_inode_mode(eb, item);
473 btrfs_set_inode_size(eb, item, 0);
475 } else if (inode_item) {
476 struct btrfs_inode_item *item;
480 * New inode, set nbytes to 0 so that the nbytes comes out
481 * properly when we replay the extents.
483 item = btrfs_item_ptr(eb, slot, struct btrfs_inode_item);
484 btrfs_set_inode_nbytes(eb, item, 0);
487 * If this is a directory we need to reset the i_size to 0 so
488 * that we can set it up properly when replaying the rest of
489 * the items in this log.
491 mode = btrfs_inode_mode(eb, item);
493 btrfs_set_inode_size(eb, item, 0);
496 btrfs_release_path(path);
497 /* try to insert the key into the destination tree */
498 path->skip_release_on_error = 1;
499 ret = btrfs_insert_empty_item(trans, root, path,
501 path->skip_release_on_error = 0;
503 /* make sure any existing item is the correct size */
504 if (ret == -EEXIST || ret == -EOVERFLOW) {
506 found_size = btrfs_item_size_nr(path->nodes[0],
508 if (found_size > item_size)
509 btrfs_truncate_item(path, item_size, 1);
510 else if (found_size < item_size)
511 btrfs_extend_item(path, item_size - found_size);
515 dst_ptr = btrfs_item_ptr_offset(path->nodes[0],
518 /* don't overwrite an existing inode if the generation number
519 * was logged as zero. This is done when the tree logging code
520 * is just logging an inode to make sure it exists after recovery.
522 * Also, don't overwrite i_size on directories during replay.
523 * log replay inserts and removes directory items based on the
524 * state of the tree found in the subvolume, and i_size is modified
527 if (key->type == BTRFS_INODE_ITEM_KEY && ret == -EEXIST) {
528 struct btrfs_inode_item *src_item;
529 struct btrfs_inode_item *dst_item;
531 src_item = (struct btrfs_inode_item *)src_ptr;
532 dst_item = (struct btrfs_inode_item *)dst_ptr;
534 if (btrfs_inode_generation(eb, src_item) == 0) {
535 struct extent_buffer *dst_eb = path->nodes[0];
536 const u64 ino_size = btrfs_inode_size(eb, src_item);
539 * For regular files an ino_size == 0 is used only when
540 * logging that an inode exists, as part of a directory
541 * fsync, and the inode wasn't fsynced before. In this
542 * case don't set the size of the inode in the fs/subvol
543 * tree, otherwise we would be throwing valid data away.
545 if (S_ISREG(btrfs_inode_mode(eb, src_item)) &&
546 S_ISREG(btrfs_inode_mode(dst_eb, dst_item)) &&
548 btrfs_set_inode_size(dst_eb, dst_item, ino_size);
552 if (overwrite_root &&
553 S_ISDIR(btrfs_inode_mode(eb, src_item)) &&
554 S_ISDIR(btrfs_inode_mode(path->nodes[0], dst_item))) {
556 saved_i_size = btrfs_inode_size(path->nodes[0],
561 copy_extent_buffer(path->nodes[0], eb, dst_ptr,
564 if (save_old_i_size) {
565 struct btrfs_inode_item *dst_item;
566 dst_item = (struct btrfs_inode_item *)dst_ptr;
567 btrfs_set_inode_size(path->nodes[0], dst_item, saved_i_size);
570 /* make sure the generation is filled in */
571 if (key->type == BTRFS_INODE_ITEM_KEY) {
572 struct btrfs_inode_item *dst_item;
573 dst_item = (struct btrfs_inode_item *)dst_ptr;
574 if (btrfs_inode_generation(path->nodes[0], dst_item) == 0) {
575 btrfs_set_inode_generation(path->nodes[0], dst_item,
580 btrfs_mark_buffer_dirty(path->nodes[0]);
581 btrfs_release_path(path);
586 * Item overwrite used by replay and tree logging. eb, slot and key all refer
587 * to the src data we are copying out.
589 * root is the tree we are copying into, and path is a scratch
590 * path for use in this function (it should be released on entry and
591 * will be released on exit).
593 * If the key is already in the destination tree the existing item is
594 * overwritten. If the existing item isn't big enough, it is extended.
595 * If it is too large, it is truncated.
597 * If the key isn't in the destination yet, a new item is inserted.
599 static int overwrite_item(struct btrfs_trans_handle *trans,
600 struct btrfs_root *root,
601 struct btrfs_path *path,
602 struct extent_buffer *eb, int slot,
603 struct btrfs_key *key)
607 /* Look for the key in the destination tree. */
608 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
612 return do_overwrite_item(trans, root, path, eb, slot, key);
616 * simple helper to read an inode off the disk from a given root
617 * This can only be called for subvolume roots and not for the log
619 static noinline struct inode *read_one_inode(struct btrfs_root *root,
624 inode = btrfs_iget(root->fs_info->sb, objectid, root);
630 /* replays a single extent in 'eb' at 'slot' with 'key' into the
631 * subvolume 'root'. path is released on entry and should be released
634 * extents in the log tree have not been allocated out of the extent
635 * tree yet. So, this completes the allocation, taking a reference
636 * as required if the extent already exists or creating a new extent
637 * if it isn't in the extent allocation tree yet.
639 * The extent is inserted into the file, dropping any existing extents
640 * from the file that overlap the new one.
642 static noinline int replay_one_extent(struct btrfs_trans_handle *trans,
643 struct btrfs_root *root,
644 struct btrfs_path *path,
645 struct extent_buffer *eb, int slot,
646 struct btrfs_key *key)
648 struct btrfs_drop_extents_args drop_args = { 0 };
649 struct btrfs_fs_info *fs_info = root->fs_info;
652 u64 start = key->offset;
654 struct btrfs_file_extent_item *item;
655 struct inode *inode = NULL;
659 item = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
660 found_type = btrfs_file_extent_type(eb, item);
662 if (found_type == BTRFS_FILE_EXTENT_REG ||
663 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
664 nbytes = btrfs_file_extent_num_bytes(eb, item);
665 extent_end = start + nbytes;
668 * We don't add to the inodes nbytes if we are prealloc or a
671 if (btrfs_file_extent_disk_bytenr(eb, item) == 0)
673 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
674 size = btrfs_file_extent_ram_bytes(eb, item);
675 nbytes = btrfs_file_extent_ram_bytes(eb, item);
676 extent_end = ALIGN(start + size,
677 fs_info->sectorsize);
683 inode = read_one_inode(root, key->objectid);
690 * first check to see if we already have this extent in the
691 * file. This must be done before the btrfs_drop_extents run
692 * so we don't try to drop this extent.
694 ret = btrfs_lookup_file_extent(trans, root, path,
695 btrfs_ino(BTRFS_I(inode)), start, 0);
698 (found_type == BTRFS_FILE_EXTENT_REG ||
699 found_type == BTRFS_FILE_EXTENT_PREALLOC)) {
700 struct btrfs_file_extent_item cmp1;
701 struct btrfs_file_extent_item cmp2;
702 struct btrfs_file_extent_item *existing;
703 struct extent_buffer *leaf;
705 leaf = path->nodes[0];
706 existing = btrfs_item_ptr(leaf, path->slots[0],
707 struct btrfs_file_extent_item);
709 read_extent_buffer(eb, &cmp1, (unsigned long)item,
711 read_extent_buffer(leaf, &cmp2, (unsigned long)existing,
715 * we already have a pointer to this exact extent,
716 * we don't have to do anything
718 if (memcmp(&cmp1, &cmp2, sizeof(cmp1)) == 0) {
719 btrfs_release_path(path);
723 btrfs_release_path(path);
725 /* drop any overlapping extents */
726 drop_args.start = start;
727 drop_args.end = extent_end;
728 drop_args.drop_cache = true;
729 ret = btrfs_drop_extents(trans, root, BTRFS_I(inode), &drop_args);
733 if (found_type == BTRFS_FILE_EXTENT_REG ||
734 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
736 unsigned long dest_offset;
737 struct btrfs_key ins;
739 if (btrfs_file_extent_disk_bytenr(eb, item) == 0 &&
740 btrfs_fs_incompat(fs_info, NO_HOLES))
743 ret = btrfs_insert_empty_item(trans, root, path, key,
747 dest_offset = btrfs_item_ptr_offset(path->nodes[0],
749 copy_extent_buffer(path->nodes[0], eb, dest_offset,
750 (unsigned long)item, sizeof(*item));
752 ins.objectid = btrfs_file_extent_disk_bytenr(eb, item);
753 ins.offset = btrfs_file_extent_disk_num_bytes(eb, item);
754 ins.type = BTRFS_EXTENT_ITEM_KEY;
755 offset = key->offset - btrfs_file_extent_offset(eb, item);
758 * Manually record dirty extent, as here we did a shallow
759 * file extent item copy and skip normal backref update,
760 * but modifying extent tree all by ourselves.
761 * So need to manually record dirty extent for qgroup,
762 * as the owner of the file extent changed from log tree
763 * (doesn't affect qgroup) to fs/file tree(affects qgroup)
765 ret = btrfs_qgroup_trace_extent(trans,
766 btrfs_file_extent_disk_bytenr(eb, item),
767 btrfs_file_extent_disk_num_bytes(eb, item),
772 if (ins.objectid > 0) {
773 struct btrfs_ref ref = { 0 };
776 LIST_HEAD(ordered_sums);
779 * is this extent already allocated in the extent
780 * allocation tree? If so, just add a reference
782 ret = btrfs_lookup_data_extent(fs_info, ins.objectid,
786 } else if (ret == 0) {
787 btrfs_init_generic_ref(&ref,
788 BTRFS_ADD_DELAYED_REF,
789 ins.objectid, ins.offset, 0);
790 btrfs_init_data_ref(&ref,
791 root->root_key.objectid,
792 key->objectid, offset, 0, false);
793 ret = btrfs_inc_extent_ref(trans, &ref);
798 * insert the extent pointer in the extent
801 ret = btrfs_alloc_logged_file_extent(trans,
802 root->root_key.objectid,
803 key->objectid, offset, &ins);
807 btrfs_release_path(path);
809 if (btrfs_file_extent_compression(eb, item)) {
810 csum_start = ins.objectid;
811 csum_end = csum_start + ins.offset;
813 csum_start = ins.objectid +
814 btrfs_file_extent_offset(eb, item);
815 csum_end = csum_start +
816 btrfs_file_extent_num_bytes(eb, item);
819 ret = btrfs_lookup_csums_range(root->log_root,
820 csum_start, csum_end - 1,
825 * Now delete all existing cums in the csum root that
826 * cover our range. We do this because we can have an
827 * extent that is completely referenced by one file
828 * extent item and partially referenced by another
829 * file extent item (like after using the clone or
830 * extent_same ioctls). In this case if we end up doing
831 * the replay of the one that partially references the
832 * extent first, and we do not do the csum deletion
833 * below, we can get 2 csum items in the csum tree that
834 * overlap each other. For example, imagine our log has
835 * the two following file extent items:
837 * key (257 EXTENT_DATA 409600)
838 * extent data disk byte 12845056 nr 102400
839 * extent data offset 20480 nr 20480 ram 102400
841 * key (257 EXTENT_DATA 819200)
842 * extent data disk byte 12845056 nr 102400
843 * extent data offset 0 nr 102400 ram 102400
845 * Where the second one fully references the 100K extent
846 * that starts at disk byte 12845056, and the log tree
847 * has a single csum item that covers the entire range
850 * key (EXTENT_CSUM EXTENT_CSUM 12845056) itemsize 100
852 * After the first file extent item is replayed, the
853 * csum tree gets the following csum item:
855 * key (EXTENT_CSUM EXTENT_CSUM 12865536) itemsize 20
857 * Which covers the 20K sub-range starting at offset 20K
858 * of our extent. Now when we replay the second file
859 * extent item, if we do not delete existing csum items
860 * that cover any of its blocks, we end up getting two
861 * csum items in our csum tree that overlap each other:
863 * key (EXTENT_CSUM EXTENT_CSUM 12845056) itemsize 100
864 * key (EXTENT_CSUM EXTENT_CSUM 12865536) itemsize 20
866 * Which is a problem, because after this anyone trying
867 * to lookup up for the checksum of any block of our
868 * extent starting at an offset of 40K or higher, will
869 * end up looking at the second csum item only, which
870 * does not contain the checksum for any block starting
871 * at offset 40K or higher of our extent.
873 while (!list_empty(&ordered_sums)) {
874 struct btrfs_ordered_sum *sums;
875 sums = list_entry(ordered_sums.next,
876 struct btrfs_ordered_sum,
879 ret = btrfs_del_csums(trans,
884 ret = btrfs_csum_file_blocks(trans,
885 fs_info->csum_root, sums);
886 list_del(&sums->list);
892 btrfs_release_path(path);
894 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
895 /* inline extents are easy, we just overwrite them */
896 ret = overwrite_item(trans, root, path, eb, slot, key);
901 ret = btrfs_inode_set_file_extent_range(BTRFS_I(inode), start,
907 btrfs_update_inode_bytes(BTRFS_I(inode), nbytes, drop_args.bytes_found);
908 ret = btrfs_update_inode(trans, root, BTRFS_I(inode));
916 * when cleaning up conflicts between the directory names in the
917 * subvolume, directory names in the log and directory names in the
918 * inode back references, we may have to unlink inodes from directories.
920 * This is a helper function to do the unlink of a specific directory
923 static noinline int drop_one_dir_item(struct btrfs_trans_handle *trans,
924 struct btrfs_path *path,
925 struct btrfs_inode *dir,
926 struct btrfs_dir_item *di)
928 struct btrfs_root *root = dir->root;
932 struct extent_buffer *leaf;
933 struct btrfs_key location;
936 leaf = path->nodes[0];
938 btrfs_dir_item_key_to_cpu(leaf, di, &location);
939 name_len = btrfs_dir_name_len(leaf, di);
940 name = kmalloc(name_len, GFP_NOFS);
944 read_extent_buffer(leaf, name, (unsigned long)(di + 1), name_len);
945 btrfs_release_path(path);
947 inode = read_one_inode(root, location.objectid);
953 ret = link_to_fixup_dir(trans, root, path, location.objectid);
957 ret = btrfs_unlink_inode(trans, dir, BTRFS_I(inode), name,
962 ret = btrfs_run_delayed_items(trans);
970 * See if a given name and sequence number found in an inode back reference are
971 * already in a directory and correctly point to this inode.
973 * Returns: < 0 on error, 0 if the directory entry does not exists and 1 if it
976 static noinline int inode_in_dir(struct btrfs_root *root,
977 struct btrfs_path *path,
978 u64 dirid, u64 objectid, u64 index,
979 const char *name, int name_len)
981 struct btrfs_dir_item *di;
982 struct btrfs_key location;
985 di = btrfs_lookup_dir_index_item(NULL, root, path, dirid,
986 index, name, name_len, 0);
991 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location);
992 if (location.objectid != objectid)
998 btrfs_release_path(path);
999 di = btrfs_lookup_dir_item(NULL, root, path, dirid, name, name_len, 0);
1004 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location);
1005 if (location.objectid == objectid)
1009 btrfs_release_path(path);
1014 * helper function to check a log tree for a named back reference in
1015 * an inode. This is used to decide if a back reference that is
1016 * found in the subvolume conflicts with what we find in the log.
1018 * inode backreferences may have multiple refs in a single item,
1019 * during replay we process one reference at a time, and we don't
1020 * want to delete valid links to a file from the subvolume if that
1021 * link is also in the log.
1023 static noinline int backref_in_log(struct btrfs_root *log,
1024 struct btrfs_key *key,
1026 const char *name, int namelen)
1028 struct btrfs_path *path;
1031 path = btrfs_alloc_path();
1035 ret = btrfs_search_slot(NULL, log, key, path, 0, 0);
1038 } else if (ret == 1) {
1043 if (key->type == BTRFS_INODE_EXTREF_KEY)
1044 ret = !!btrfs_find_name_in_ext_backref(path->nodes[0],
1049 ret = !!btrfs_find_name_in_backref(path->nodes[0],
1053 btrfs_free_path(path);
1057 static inline int __add_inode_ref(struct btrfs_trans_handle *trans,
1058 struct btrfs_root *root,
1059 struct btrfs_path *path,
1060 struct btrfs_root *log_root,
1061 struct btrfs_inode *dir,
1062 struct btrfs_inode *inode,
1063 u64 inode_objectid, u64 parent_objectid,
1064 u64 ref_index, char *name, int namelen,
1069 int victim_name_len;
1070 struct extent_buffer *leaf;
1071 struct btrfs_dir_item *di;
1072 struct btrfs_key search_key;
1073 struct btrfs_inode_extref *extref;
1076 /* Search old style refs */
1077 search_key.objectid = inode_objectid;
1078 search_key.type = BTRFS_INODE_REF_KEY;
1079 search_key.offset = parent_objectid;
1080 ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
1082 struct btrfs_inode_ref *victim_ref;
1084 unsigned long ptr_end;
1086 leaf = path->nodes[0];
1088 /* are we trying to overwrite a back ref for the root directory
1089 * if so, just jump out, we're done
1091 if (search_key.objectid == search_key.offset)
1094 /* check all the names in this back reference to see
1095 * if they are in the log. if so, we allow them to stay
1096 * otherwise they must be unlinked as a conflict
1098 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
1099 ptr_end = ptr + btrfs_item_size_nr(leaf, path->slots[0]);
1100 while (ptr < ptr_end) {
1101 victim_ref = (struct btrfs_inode_ref *)ptr;
1102 victim_name_len = btrfs_inode_ref_name_len(leaf,
1104 victim_name = kmalloc(victim_name_len, GFP_NOFS);
1108 read_extent_buffer(leaf, victim_name,
1109 (unsigned long)(victim_ref + 1),
1112 ret = backref_in_log(log_root, &search_key,
1113 parent_objectid, victim_name,
1119 inc_nlink(&inode->vfs_inode);
1120 btrfs_release_path(path);
1122 ret = btrfs_unlink_inode(trans, dir, inode,
1123 victim_name, victim_name_len);
1127 ret = btrfs_run_delayed_items(trans);
1135 ptr = (unsigned long)(victim_ref + 1) + victim_name_len;
1139 * NOTE: we have searched root tree and checked the
1140 * corresponding ref, it does not need to check again.
1144 btrfs_release_path(path);
1146 /* Same search but for extended refs */
1147 extref = btrfs_lookup_inode_extref(NULL, root, path, name, namelen,
1148 inode_objectid, parent_objectid, 0,
1150 if (!IS_ERR_OR_NULL(extref)) {
1154 struct inode *victim_parent;
1156 leaf = path->nodes[0];
1158 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1159 base = btrfs_item_ptr_offset(leaf, path->slots[0]);
1161 while (cur_offset < item_size) {
1162 extref = (struct btrfs_inode_extref *)(base + cur_offset);
1164 victim_name_len = btrfs_inode_extref_name_len(leaf, extref);
1166 if (btrfs_inode_extref_parent(leaf, extref) != parent_objectid)
1169 victim_name = kmalloc(victim_name_len, GFP_NOFS);
1172 read_extent_buffer(leaf, victim_name, (unsigned long)&extref->name,
1175 search_key.objectid = inode_objectid;
1176 search_key.type = BTRFS_INODE_EXTREF_KEY;
1177 search_key.offset = btrfs_extref_hash(parent_objectid,
1180 ret = backref_in_log(log_root, &search_key,
1181 parent_objectid, victim_name,
1187 victim_parent = read_one_inode(root,
1189 if (victim_parent) {
1190 inc_nlink(&inode->vfs_inode);
1191 btrfs_release_path(path);
1193 ret = btrfs_unlink_inode(trans,
1194 BTRFS_I(victim_parent),
1199 ret = btrfs_run_delayed_items(
1202 iput(victim_parent);
1211 cur_offset += victim_name_len + sizeof(*extref);
1215 btrfs_release_path(path);
1217 /* look for a conflicting sequence number */
1218 di = btrfs_lookup_dir_index_item(trans, root, path, btrfs_ino(dir),
1219 ref_index, name, namelen, 0);
1223 ret = drop_one_dir_item(trans, path, dir, di);
1227 btrfs_release_path(path);
1229 /* look for a conflicting name */
1230 di = btrfs_lookup_dir_item(trans, root, path, btrfs_ino(dir),
1235 ret = drop_one_dir_item(trans, path, dir, di);
1239 btrfs_release_path(path);
1244 static int extref_get_fields(struct extent_buffer *eb, unsigned long ref_ptr,
1245 u32 *namelen, char **name, u64 *index,
1246 u64 *parent_objectid)
1248 struct btrfs_inode_extref *extref;
1250 extref = (struct btrfs_inode_extref *)ref_ptr;
1252 *namelen = btrfs_inode_extref_name_len(eb, extref);
1253 *name = kmalloc(*namelen, GFP_NOFS);
1257 read_extent_buffer(eb, *name, (unsigned long)&extref->name,
1261 *index = btrfs_inode_extref_index(eb, extref);
1262 if (parent_objectid)
1263 *parent_objectid = btrfs_inode_extref_parent(eb, extref);
1268 static int ref_get_fields(struct extent_buffer *eb, unsigned long ref_ptr,
1269 u32 *namelen, char **name, u64 *index)
1271 struct btrfs_inode_ref *ref;
1273 ref = (struct btrfs_inode_ref *)ref_ptr;
1275 *namelen = btrfs_inode_ref_name_len(eb, ref);
1276 *name = kmalloc(*namelen, GFP_NOFS);
1280 read_extent_buffer(eb, *name, (unsigned long)(ref + 1), *namelen);
1283 *index = btrfs_inode_ref_index(eb, ref);
1289 * Take an inode reference item from the log tree and iterate all names from the
1290 * inode reference item in the subvolume tree with the same key (if it exists).
1291 * For any name that is not in the inode reference item from the log tree, do a
1292 * proper unlink of that name (that is, remove its entry from the inode
1293 * reference item and both dir index keys).
1295 static int unlink_old_inode_refs(struct btrfs_trans_handle *trans,
1296 struct btrfs_root *root,
1297 struct btrfs_path *path,
1298 struct btrfs_inode *inode,
1299 struct extent_buffer *log_eb,
1301 struct btrfs_key *key)
1304 unsigned long ref_ptr;
1305 unsigned long ref_end;
1306 struct extent_buffer *eb;
1309 btrfs_release_path(path);
1310 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
1318 eb = path->nodes[0];
1319 ref_ptr = btrfs_item_ptr_offset(eb, path->slots[0]);
1320 ref_end = ref_ptr + btrfs_item_size_nr(eb, path->slots[0]);
1321 while (ref_ptr < ref_end) {
1326 if (key->type == BTRFS_INODE_EXTREF_KEY) {
1327 ret = extref_get_fields(eb, ref_ptr, &namelen, &name,
1330 parent_id = key->offset;
1331 ret = ref_get_fields(eb, ref_ptr, &namelen, &name,
1337 if (key->type == BTRFS_INODE_EXTREF_KEY)
1338 ret = !!btrfs_find_name_in_ext_backref(log_eb, log_slot,
1342 ret = !!btrfs_find_name_in_backref(log_eb, log_slot,
1348 btrfs_release_path(path);
1349 dir = read_one_inode(root, parent_id);
1355 ret = btrfs_unlink_inode(trans, BTRFS_I(dir),
1356 inode, name, namelen);
1366 if (key->type == BTRFS_INODE_EXTREF_KEY)
1367 ref_ptr += sizeof(struct btrfs_inode_extref);
1369 ref_ptr += sizeof(struct btrfs_inode_ref);
1373 btrfs_release_path(path);
1377 static int btrfs_inode_ref_exists(struct inode *inode, struct inode *dir,
1378 const u8 ref_type, const char *name,
1381 struct btrfs_key key;
1382 struct btrfs_path *path;
1383 const u64 parent_id = btrfs_ino(BTRFS_I(dir));
1386 path = btrfs_alloc_path();
1390 key.objectid = btrfs_ino(BTRFS_I(inode));
1391 key.type = ref_type;
1392 if (key.type == BTRFS_INODE_REF_KEY)
1393 key.offset = parent_id;
1395 key.offset = btrfs_extref_hash(parent_id, name, namelen);
1397 ret = btrfs_search_slot(NULL, BTRFS_I(inode)->root, &key, path, 0, 0);
1404 if (key.type == BTRFS_INODE_EXTREF_KEY)
1405 ret = !!btrfs_find_name_in_ext_backref(path->nodes[0],
1406 path->slots[0], parent_id, name, namelen);
1408 ret = !!btrfs_find_name_in_backref(path->nodes[0], path->slots[0],
1412 btrfs_free_path(path);
1416 static int add_link(struct btrfs_trans_handle *trans,
1417 struct inode *dir, struct inode *inode, const char *name,
1418 int namelen, u64 ref_index)
1420 struct btrfs_root *root = BTRFS_I(dir)->root;
1421 struct btrfs_dir_item *dir_item;
1422 struct btrfs_key key;
1423 struct btrfs_path *path;
1424 struct inode *other_inode = NULL;
1427 path = btrfs_alloc_path();
1431 dir_item = btrfs_lookup_dir_item(NULL, root, path,
1432 btrfs_ino(BTRFS_I(dir)),
1435 btrfs_release_path(path);
1437 } else if (IS_ERR(dir_item)) {
1438 ret = PTR_ERR(dir_item);
1443 * Our inode's dentry collides with the dentry of another inode which is
1444 * in the log but not yet processed since it has a higher inode number.
1445 * So delete that other dentry.
1447 btrfs_dir_item_key_to_cpu(path->nodes[0], dir_item, &key);
1448 btrfs_release_path(path);
1449 other_inode = read_one_inode(root, key.objectid);
1454 ret = btrfs_unlink_inode(trans, BTRFS_I(dir), BTRFS_I(other_inode),
1459 * If we dropped the link count to 0, bump it so that later the iput()
1460 * on the inode will not free it. We will fixup the link count later.
1462 if (other_inode->i_nlink == 0)
1463 inc_nlink(other_inode);
1465 ret = btrfs_run_delayed_items(trans);
1469 ret = btrfs_add_link(trans, BTRFS_I(dir), BTRFS_I(inode),
1470 name, namelen, 0, ref_index);
1473 btrfs_free_path(path);
1479 * replay one inode back reference item found in the log tree.
1480 * eb, slot and key refer to the buffer and key found in the log tree.
1481 * root is the destination we are replaying into, and path is for temp
1482 * use by this function. (it should be released on return).
1484 static noinline int add_inode_ref(struct btrfs_trans_handle *trans,
1485 struct btrfs_root *root,
1486 struct btrfs_root *log,
1487 struct btrfs_path *path,
1488 struct extent_buffer *eb, int slot,
1489 struct btrfs_key *key)
1491 struct inode *dir = NULL;
1492 struct inode *inode = NULL;
1493 unsigned long ref_ptr;
1494 unsigned long ref_end;
1498 int search_done = 0;
1499 int log_ref_ver = 0;
1500 u64 parent_objectid;
1503 int ref_struct_size;
1505 ref_ptr = btrfs_item_ptr_offset(eb, slot);
1506 ref_end = ref_ptr + btrfs_item_size_nr(eb, slot);
1508 if (key->type == BTRFS_INODE_EXTREF_KEY) {
1509 struct btrfs_inode_extref *r;
1511 ref_struct_size = sizeof(struct btrfs_inode_extref);
1513 r = (struct btrfs_inode_extref *)ref_ptr;
1514 parent_objectid = btrfs_inode_extref_parent(eb, r);
1516 ref_struct_size = sizeof(struct btrfs_inode_ref);
1517 parent_objectid = key->offset;
1519 inode_objectid = key->objectid;
1522 * it is possible that we didn't log all the parent directories
1523 * for a given inode. If we don't find the dir, just don't
1524 * copy the back ref in. The link count fixup code will take
1527 dir = read_one_inode(root, parent_objectid);
1533 inode = read_one_inode(root, inode_objectid);
1539 while (ref_ptr < ref_end) {
1541 ret = extref_get_fields(eb, ref_ptr, &namelen, &name,
1542 &ref_index, &parent_objectid);
1544 * parent object can change from one array
1548 dir = read_one_inode(root, parent_objectid);
1554 ret = ref_get_fields(eb, ref_ptr, &namelen, &name,
1560 ret = inode_in_dir(root, path, btrfs_ino(BTRFS_I(dir)),
1561 btrfs_ino(BTRFS_I(inode)), ref_index,
1565 } else if (ret == 0) {
1567 * look for a conflicting back reference in the
1568 * metadata. if we find one we have to unlink that name
1569 * of the file before we add our new link. Later on, we
1570 * overwrite any existing back reference, and we don't
1571 * want to create dangling pointers in the directory.
1575 ret = __add_inode_ref(trans, root, path, log,
1580 ref_index, name, namelen,
1590 * If a reference item already exists for this inode
1591 * with the same parent and name, but different index,
1592 * drop it and the corresponding directory index entries
1593 * from the parent before adding the new reference item
1594 * and dir index entries, otherwise we would fail with
1595 * -EEXIST returned from btrfs_add_link() below.
1597 ret = btrfs_inode_ref_exists(inode, dir, key->type,
1600 ret = btrfs_unlink_inode(trans,
1605 * If we dropped the link count to 0, bump it so
1606 * that later the iput() on the inode will not
1607 * free it. We will fixup the link count later.
1609 if (!ret && inode->i_nlink == 0)
1615 /* insert our name */
1616 ret = add_link(trans, dir, inode, name, namelen,
1621 ret = btrfs_update_inode(trans, root, BTRFS_I(inode));
1625 /* Else, ret == 1, we already have a perfect match, we're done. */
1627 ref_ptr = (unsigned long)(ref_ptr + ref_struct_size) + namelen;
1637 * Before we overwrite the inode reference item in the subvolume tree
1638 * with the item from the log tree, we must unlink all names from the
1639 * parent directory that are in the subvolume's tree inode reference
1640 * item, otherwise we end up with an inconsistent subvolume tree where
1641 * dir index entries exist for a name but there is no inode reference
1642 * item with the same name.
1644 ret = unlink_old_inode_refs(trans, root, path, BTRFS_I(inode), eb, slot,
1649 /* finally write the back reference in the inode */
1650 ret = overwrite_item(trans, root, path, eb, slot, key);
1652 btrfs_release_path(path);
1659 static int count_inode_extrefs(struct btrfs_root *root,
1660 struct btrfs_inode *inode, struct btrfs_path *path)
1664 unsigned int nlink = 0;
1667 u64 inode_objectid = btrfs_ino(inode);
1670 struct btrfs_inode_extref *extref;
1671 struct extent_buffer *leaf;
1674 ret = btrfs_find_one_extref(root, inode_objectid, offset, path,
1679 leaf = path->nodes[0];
1680 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1681 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
1684 while (cur_offset < item_size) {
1685 extref = (struct btrfs_inode_extref *) (ptr + cur_offset);
1686 name_len = btrfs_inode_extref_name_len(leaf, extref);
1690 cur_offset += name_len + sizeof(*extref);
1694 btrfs_release_path(path);
1696 btrfs_release_path(path);
1698 if (ret < 0 && ret != -ENOENT)
1703 static int count_inode_refs(struct btrfs_root *root,
1704 struct btrfs_inode *inode, struct btrfs_path *path)
1707 struct btrfs_key key;
1708 unsigned int nlink = 0;
1710 unsigned long ptr_end;
1712 u64 ino = btrfs_ino(inode);
1715 key.type = BTRFS_INODE_REF_KEY;
1716 key.offset = (u64)-1;
1719 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1723 if (path->slots[0] == 0)
1728 btrfs_item_key_to_cpu(path->nodes[0], &key,
1730 if (key.objectid != ino ||
1731 key.type != BTRFS_INODE_REF_KEY)
1733 ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
1734 ptr_end = ptr + btrfs_item_size_nr(path->nodes[0],
1736 while (ptr < ptr_end) {
1737 struct btrfs_inode_ref *ref;
1739 ref = (struct btrfs_inode_ref *)ptr;
1740 name_len = btrfs_inode_ref_name_len(path->nodes[0],
1742 ptr = (unsigned long)(ref + 1) + name_len;
1746 if (key.offset == 0)
1748 if (path->slots[0] > 0) {
1753 btrfs_release_path(path);
1755 btrfs_release_path(path);
1761 * There are a few corners where the link count of the file can't
1762 * be properly maintained during replay. So, instead of adding
1763 * lots of complexity to the log code, we just scan the backrefs
1764 * for any file that has been through replay.
1766 * The scan will update the link count on the inode to reflect the
1767 * number of back refs found. If it goes down to zero, the iput
1768 * will free the inode.
1770 static noinline int fixup_inode_link_count(struct btrfs_trans_handle *trans,
1771 struct btrfs_root *root,
1772 struct inode *inode)
1774 struct btrfs_path *path;
1777 u64 ino = btrfs_ino(BTRFS_I(inode));
1779 path = btrfs_alloc_path();
1783 ret = count_inode_refs(root, BTRFS_I(inode), path);
1789 ret = count_inode_extrefs(root, BTRFS_I(inode), path);
1797 if (nlink != inode->i_nlink) {
1798 set_nlink(inode, nlink);
1799 ret = btrfs_update_inode(trans, root, BTRFS_I(inode));
1803 BTRFS_I(inode)->index_cnt = (u64)-1;
1805 if (inode->i_nlink == 0) {
1806 if (S_ISDIR(inode->i_mode)) {
1807 ret = replay_dir_deletes(trans, root, NULL, path,
1812 ret = btrfs_insert_orphan_item(trans, root, ino);
1818 btrfs_free_path(path);
1822 static noinline int fixup_inode_link_counts(struct btrfs_trans_handle *trans,
1823 struct btrfs_root *root,
1824 struct btrfs_path *path)
1827 struct btrfs_key key;
1828 struct inode *inode;
1830 key.objectid = BTRFS_TREE_LOG_FIXUP_OBJECTID;
1831 key.type = BTRFS_ORPHAN_ITEM_KEY;
1832 key.offset = (u64)-1;
1834 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1840 if (path->slots[0] == 0)
1845 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1846 if (key.objectid != BTRFS_TREE_LOG_FIXUP_OBJECTID ||
1847 key.type != BTRFS_ORPHAN_ITEM_KEY)
1850 ret = btrfs_del_item(trans, root, path);
1854 btrfs_release_path(path);
1855 inode = read_one_inode(root, key.offset);
1861 ret = fixup_inode_link_count(trans, root, inode);
1867 * fixup on a directory may create new entries,
1868 * make sure we always look for the highset possible
1871 key.offset = (u64)-1;
1873 btrfs_release_path(path);
1879 * record a given inode in the fixup dir so we can check its link
1880 * count when replay is done. The link count is incremented here
1881 * so the inode won't go away until we check it
1883 static noinline int link_to_fixup_dir(struct btrfs_trans_handle *trans,
1884 struct btrfs_root *root,
1885 struct btrfs_path *path,
1888 struct btrfs_key key;
1890 struct inode *inode;
1892 inode = read_one_inode(root, objectid);
1896 key.objectid = BTRFS_TREE_LOG_FIXUP_OBJECTID;
1897 key.type = BTRFS_ORPHAN_ITEM_KEY;
1898 key.offset = objectid;
1900 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1902 btrfs_release_path(path);
1904 if (!inode->i_nlink)
1905 set_nlink(inode, 1);
1908 ret = btrfs_update_inode(trans, root, BTRFS_I(inode));
1909 } else if (ret == -EEXIST) {
1918 * when replaying the log for a directory, we only insert names
1919 * for inodes that actually exist. This means an fsync on a directory
1920 * does not implicitly fsync all the new files in it
1922 static noinline int insert_one_name(struct btrfs_trans_handle *trans,
1923 struct btrfs_root *root,
1924 u64 dirid, u64 index,
1925 char *name, int name_len,
1926 struct btrfs_key *location)
1928 struct inode *inode;
1932 inode = read_one_inode(root, location->objectid);
1936 dir = read_one_inode(root, dirid);
1942 ret = btrfs_add_link(trans, BTRFS_I(dir), BTRFS_I(inode), name,
1943 name_len, 1, index);
1945 /* FIXME, put inode into FIXUP list */
1953 * take a single entry in a log directory item and replay it into
1956 * if a conflicting item exists in the subdirectory already,
1957 * the inode it points to is unlinked and put into the link count
1960 * If a name from the log points to a file or directory that does
1961 * not exist in the FS, it is skipped. fsyncs on directories
1962 * do not force down inodes inside that directory, just changes to the
1963 * names or unlinks in a directory.
1965 * Returns < 0 on error, 0 if the name wasn't replayed (dentry points to a
1966 * non-existing inode) and 1 if the name was replayed.
1968 static noinline int replay_one_name(struct btrfs_trans_handle *trans,
1969 struct btrfs_root *root,
1970 struct btrfs_path *path,
1971 struct extent_buffer *eb,
1972 struct btrfs_dir_item *di,
1973 struct btrfs_key *key)
1977 struct btrfs_dir_item *dst_di;
1978 struct btrfs_key found_key;
1979 struct btrfs_key log_key;
1984 bool update_size = (key->type == BTRFS_DIR_INDEX_KEY);
1985 bool name_added = false;
1987 dir = read_one_inode(root, key->objectid);
1991 name_len = btrfs_dir_name_len(eb, di);
1992 name = kmalloc(name_len, GFP_NOFS);
1998 log_type = btrfs_dir_type(eb, di);
1999 read_extent_buffer(eb, name, (unsigned long)(di + 1),
2002 btrfs_dir_item_key_to_cpu(eb, di, &log_key);
2003 ret = btrfs_lookup_inode(trans, root, path, &log_key, 0);
2004 btrfs_release_path(path);
2007 exists = (ret == 0);
2010 if (key->type == BTRFS_DIR_ITEM_KEY) {
2011 dst_di = btrfs_lookup_dir_item(trans, root, path, key->objectid,
2013 } else if (key->type == BTRFS_DIR_INDEX_KEY) {
2014 dst_di = btrfs_lookup_dir_index_item(trans, root, path,
2024 if (IS_ERR(dst_di)) {
2025 ret = PTR_ERR(dst_di);
2027 } else if (!dst_di) {
2028 /* we need a sequence number to insert, so we only
2029 * do inserts for the BTRFS_DIR_INDEX_KEY types
2031 if (key->type != BTRFS_DIR_INDEX_KEY)
2036 btrfs_dir_item_key_to_cpu(path->nodes[0], dst_di, &found_key);
2037 /* the existing item matches the logged item */
2038 if (found_key.objectid == log_key.objectid &&
2039 found_key.type == log_key.type &&
2040 found_key.offset == log_key.offset &&
2041 btrfs_dir_type(path->nodes[0], dst_di) == log_type) {
2042 update_size = false;
2047 * don't drop the conflicting directory entry if the inode
2048 * for the new entry doesn't exist
2053 ret = drop_one_dir_item(trans, path, BTRFS_I(dir), dst_di);
2057 if (key->type == BTRFS_DIR_INDEX_KEY)
2060 btrfs_release_path(path);
2061 if (!ret && update_size) {
2062 btrfs_i_size_write(BTRFS_I(dir), dir->i_size + name_len * 2);
2063 ret = btrfs_update_inode(trans, root, BTRFS_I(dir));
2067 if (!ret && name_added)
2073 * Check if the inode reference exists in the log for the given name,
2074 * inode and parent inode
2076 found_key.objectid = log_key.objectid;
2077 found_key.type = BTRFS_INODE_REF_KEY;
2078 found_key.offset = key->objectid;
2079 ret = backref_in_log(root->log_root, &found_key, 0, name, name_len);
2083 /* The dentry will be added later. */
2085 update_size = false;
2089 found_key.objectid = log_key.objectid;
2090 found_key.type = BTRFS_INODE_EXTREF_KEY;
2091 found_key.offset = key->objectid;
2092 ret = backref_in_log(root->log_root, &found_key, key->objectid, name,
2097 /* The dentry will be added later. */
2099 update_size = false;
2102 btrfs_release_path(path);
2103 ret = insert_one_name(trans, root, key->objectid, key->offset,
2104 name, name_len, &log_key);
2105 if (ret && ret != -ENOENT && ret != -EEXIST)
2109 update_size = false;
2115 * find all the names in a directory item and reconcile them into
2116 * the subvolume. Only BTRFS_DIR_ITEM_KEY types will have more than
2117 * one name in a directory item, but the same code gets used for
2118 * both directory index types
2120 static noinline int replay_one_dir_item(struct btrfs_trans_handle *trans,
2121 struct btrfs_root *root,
2122 struct btrfs_path *path,
2123 struct extent_buffer *eb, int slot,
2124 struct btrfs_key *key)
2127 u32 item_size = btrfs_item_size_nr(eb, slot);
2128 struct btrfs_dir_item *di;
2131 unsigned long ptr_end;
2132 struct btrfs_path *fixup_path = NULL;
2134 ptr = btrfs_item_ptr_offset(eb, slot);
2135 ptr_end = ptr + item_size;
2136 while (ptr < ptr_end) {
2137 di = (struct btrfs_dir_item *)ptr;
2138 name_len = btrfs_dir_name_len(eb, di);
2139 ret = replay_one_name(trans, root, path, eb, di, key);
2142 ptr = (unsigned long)(di + 1);
2146 * If this entry refers to a non-directory (directories can not
2147 * have a link count > 1) and it was added in the transaction
2148 * that was not committed, make sure we fixup the link count of
2149 * the inode it the entry points to. Otherwise something like
2150 * the following would result in a directory pointing to an
2151 * inode with a wrong link that does not account for this dir
2159 * ln testdir/bar testdir/bar_link
2160 * ln testdir/foo testdir/foo_link
2161 * xfs_io -c "fsync" testdir/bar
2165 * mount fs, log replay happens
2167 * File foo would remain with a link count of 1 when it has two
2168 * entries pointing to it in the directory testdir. This would
2169 * make it impossible to ever delete the parent directory has
2170 * it would result in stale dentries that can never be deleted.
2172 if (ret == 1 && btrfs_dir_type(eb, di) != BTRFS_FT_DIR) {
2173 struct btrfs_key di_key;
2176 fixup_path = btrfs_alloc_path();
2183 btrfs_dir_item_key_to_cpu(eb, di, &di_key);
2184 ret = link_to_fixup_dir(trans, root, fixup_path,
2191 btrfs_free_path(fixup_path);
2196 * directory replay has two parts. There are the standard directory
2197 * items in the log copied from the subvolume, and range items
2198 * created in the log while the subvolume was logged.
2200 * The range items tell us which parts of the key space the log
2201 * is authoritative for. During replay, if a key in the subvolume
2202 * directory is in a logged range item, but not actually in the log
2203 * that means it was deleted from the directory before the fsync
2204 * and should be removed.
2206 static noinline int find_dir_range(struct btrfs_root *root,
2207 struct btrfs_path *path,
2208 u64 dirid, int key_type,
2209 u64 *start_ret, u64 *end_ret)
2211 struct btrfs_key key;
2213 struct btrfs_dir_log_item *item;
2217 if (*start_ret == (u64)-1)
2220 key.objectid = dirid;
2221 key.type = key_type;
2222 key.offset = *start_ret;
2224 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2228 if (path->slots[0] == 0)
2233 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
2235 if (key.type != key_type || key.objectid != dirid) {
2239 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2240 struct btrfs_dir_log_item);
2241 found_end = btrfs_dir_log_end(path->nodes[0], item);
2243 if (*start_ret >= key.offset && *start_ret <= found_end) {
2245 *start_ret = key.offset;
2246 *end_ret = found_end;
2251 /* check the next slot in the tree to see if it is a valid item */
2252 nritems = btrfs_header_nritems(path->nodes[0]);
2254 if (path->slots[0] >= nritems) {
2255 ret = btrfs_next_leaf(root, path);
2260 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
2262 if (key.type != key_type || key.objectid != dirid) {
2266 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2267 struct btrfs_dir_log_item);
2268 found_end = btrfs_dir_log_end(path->nodes[0], item);
2269 *start_ret = key.offset;
2270 *end_ret = found_end;
2273 btrfs_release_path(path);
2278 * this looks for a given directory item in the log. If the directory
2279 * item is not in the log, the item is removed and the inode it points
2282 static noinline int check_item_in_log(struct btrfs_trans_handle *trans,
2283 struct btrfs_root *log,
2284 struct btrfs_path *path,
2285 struct btrfs_path *log_path,
2287 struct btrfs_key *dir_key)
2289 struct btrfs_root *root = BTRFS_I(dir)->root;
2291 struct extent_buffer *eb;
2294 struct btrfs_dir_item *di;
2295 struct btrfs_dir_item *log_di;
2298 unsigned long ptr_end;
2300 struct inode *inode;
2301 struct btrfs_key location;
2304 eb = path->nodes[0];
2305 slot = path->slots[0];
2306 item_size = btrfs_item_size_nr(eb, slot);
2307 ptr = btrfs_item_ptr_offset(eb, slot);
2308 ptr_end = ptr + item_size;
2309 while (ptr < ptr_end) {
2310 di = (struct btrfs_dir_item *)ptr;
2311 name_len = btrfs_dir_name_len(eb, di);
2312 name = kmalloc(name_len, GFP_NOFS);
2317 read_extent_buffer(eb, name, (unsigned long)(di + 1),
2320 if (log && dir_key->type == BTRFS_DIR_ITEM_KEY) {
2321 log_di = btrfs_lookup_dir_item(trans, log, log_path,
2324 } else if (log && dir_key->type == BTRFS_DIR_INDEX_KEY) {
2325 log_di = btrfs_lookup_dir_index_item(trans, log,
2332 btrfs_dir_item_key_to_cpu(eb, di, &location);
2333 btrfs_release_path(path);
2334 btrfs_release_path(log_path);
2335 inode = read_one_inode(root, location.objectid);
2341 ret = link_to_fixup_dir(trans, root,
2342 path, location.objectid);
2350 ret = btrfs_unlink_inode(trans, BTRFS_I(dir),
2351 BTRFS_I(inode), name, name_len);
2353 ret = btrfs_run_delayed_items(trans);
2359 /* there might still be more names under this key
2360 * check and repeat if required
2362 ret = btrfs_search_slot(NULL, root, dir_key, path,
2368 } else if (IS_ERR(log_di)) {
2370 return PTR_ERR(log_di);
2372 btrfs_release_path(log_path);
2375 ptr = (unsigned long)(di + 1);
2380 btrfs_release_path(path);
2381 btrfs_release_path(log_path);
2385 static int replay_xattr_deletes(struct btrfs_trans_handle *trans,
2386 struct btrfs_root *root,
2387 struct btrfs_root *log,
2388 struct btrfs_path *path,
2391 struct btrfs_key search_key;
2392 struct btrfs_path *log_path;
2397 log_path = btrfs_alloc_path();
2401 search_key.objectid = ino;
2402 search_key.type = BTRFS_XATTR_ITEM_KEY;
2403 search_key.offset = 0;
2405 ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
2409 nritems = btrfs_header_nritems(path->nodes[0]);
2410 for (i = path->slots[0]; i < nritems; i++) {
2411 struct btrfs_key key;
2412 struct btrfs_dir_item *di;
2413 struct btrfs_dir_item *log_di;
2417 btrfs_item_key_to_cpu(path->nodes[0], &key, i);
2418 if (key.objectid != ino || key.type != BTRFS_XATTR_ITEM_KEY) {
2423 di = btrfs_item_ptr(path->nodes[0], i, struct btrfs_dir_item);
2424 total_size = btrfs_item_size_nr(path->nodes[0], i);
2426 while (cur < total_size) {
2427 u16 name_len = btrfs_dir_name_len(path->nodes[0], di);
2428 u16 data_len = btrfs_dir_data_len(path->nodes[0], di);
2429 u32 this_len = sizeof(*di) + name_len + data_len;
2432 name = kmalloc(name_len, GFP_NOFS);
2437 read_extent_buffer(path->nodes[0], name,
2438 (unsigned long)(di + 1), name_len);
2440 log_di = btrfs_lookup_xattr(NULL, log, log_path, ino,
2442 btrfs_release_path(log_path);
2444 /* Doesn't exist in log tree, so delete it. */
2445 btrfs_release_path(path);
2446 di = btrfs_lookup_xattr(trans, root, path, ino,
2447 name, name_len, -1);
2454 ret = btrfs_delete_one_dir_name(trans, root,
2458 btrfs_release_path(path);
2463 if (IS_ERR(log_di)) {
2464 ret = PTR_ERR(log_di);
2468 di = (struct btrfs_dir_item *)((char *)di + this_len);
2471 ret = btrfs_next_leaf(root, path);
2477 btrfs_free_path(log_path);
2478 btrfs_release_path(path);
2484 * deletion replay happens before we copy any new directory items
2485 * out of the log or out of backreferences from inodes. It
2486 * scans the log to find ranges of keys that log is authoritative for,
2487 * and then scans the directory to find items in those ranges that are
2488 * not present in the log.
2490 * Anything we don't find in the log is unlinked and removed from the
2493 static noinline int replay_dir_deletes(struct btrfs_trans_handle *trans,
2494 struct btrfs_root *root,
2495 struct btrfs_root *log,
2496 struct btrfs_path *path,
2497 u64 dirid, int del_all)
2501 int key_type = BTRFS_DIR_LOG_ITEM_KEY;
2503 struct btrfs_key dir_key;
2504 struct btrfs_key found_key;
2505 struct btrfs_path *log_path;
2508 dir_key.objectid = dirid;
2509 dir_key.type = BTRFS_DIR_ITEM_KEY;
2510 log_path = btrfs_alloc_path();
2514 dir = read_one_inode(root, dirid);
2515 /* it isn't an error if the inode isn't there, that can happen
2516 * because we replay the deletes before we copy in the inode item
2520 btrfs_free_path(log_path);
2528 range_end = (u64)-1;
2530 ret = find_dir_range(log, path, dirid, key_type,
2531 &range_start, &range_end);
2538 dir_key.offset = range_start;
2541 ret = btrfs_search_slot(NULL, root, &dir_key, path,
2546 nritems = btrfs_header_nritems(path->nodes[0]);
2547 if (path->slots[0] >= nritems) {
2548 ret = btrfs_next_leaf(root, path);
2554 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
2556 if (found_key.objectid != dirid ||
2557 found_key.type != dir_key.type)
2560 if (found_key.offset > range_end)
2563 ret = check_item_in_log(trans, log, path,
2568 if (found_key.offset == (u64)-1)
2570 dir_key.offset = found_key.offset + 1;
2572 btrfs_release_path(path);
2573 if (range_end == (u64)-1)
2575 range_start = range_end + 1;
2580 if (key_type == BTRFS_DIR_LOG_ITEM_KEY) {
2581 key_type = BTRFS_DIR_LOG_INDEX_KEY;
2582 dir_key.type = BTRFS_DIR_INDEX_KEY;
2583 btrfs_release_path(path);
2587 btrfs_release_path(path);
2588 btrfs_free_path(log_path);
2594 * the process_func used to replay items from the log tree. This
2595 * gets called in two different stages. The first stage just looks
2596 * for inodes and makes sure they are all copied into the subvolume.
2598 * The second stage copies all the other item types from the log into
2599 * the subvolume. The two stage approach is slower, but gets rid of
2600 * lots of complexity around inodes referencing other inodes that exist
2601 * only in the log (references come from either directory items or inode
2604 static int replay_one_buffer(struct btrfs_root *log, struct extent_buffer *eb,
2605 struct walk_control *wc, u64 gen, int level)
2608 struct btrfs_path *path;
2609 struct btrfs_root *root = wc->replay_dest;
2610 struct btrfs_key key;
2614 ret = btrfs_read_buffer(eb, gen, level, NULL);
2618 level = btrfs_header_level(eb);
2623 path = btrfs_alloc_path();
2627 nritems = btrfs_header_nritems(eb);
2628 for (i = 0; i < nritems; i++) {
2629 btrfs_item_key_to_cpu(eb, &key, i);
2631 /* inode keys are done during the first stage */
2632 if (key.type == BTRFS_INODE_ITEM_KEY &&
2633 wc->stage == LOG_WALK_REPLAY_INODES) {
2634 struct btrfs_inode_item *inode_item;
2637 inode_item = btrfs_item_ptr(eb, i,
2638 struct btrfs_inode_item);
2640 * If we have a tmpfile (O_TMPFILE) that got fsync'ed
2641 * and never got linked before the fsync, skip it, as
2642 * replaying it is pointless since it would be deleted
2643 * later. We skip logging tmpfiles, but it's always
2644 * possible we are replaying a log created with a kernel
2645 * that used to log tmpfiles.
2647 if (btrfs_inode_nlink(eb, inode_item) == 0) {
2648 wc->ignore_cur_inode = true;
2651 wc->ignore_cur_inode = false;
2653 ret = replay_xattr_deletes(wc->trans, root, log,
2654 path, key.objectid);
2657 mode = btrfs_inode_mode(eb, inode_item);
2658 if (S_ISDIR(mode)) {
2659 ret = replay_dir_deletes(wc->trans,
2660 root, log, path, key.objectid, 0);
2664 ret = overwrite_item(wc->trans, root, path,
2670 * Before replaying extents, truncate the inode to its
2671 * size. We need to do it now and not after log replay
2672 * because before an fsync we can have prealloc extents
2673 * added beyond the inode's i_size. If we did it after,
2674 * through orphan cleanup for example, we would drop
2675 * those prealloc extents just after replaying them.
2677 if (S_ISREG(mode)) {
2678 struct btrfs_drop_extents_args drop_args = { 0 };
2679 struct inode *inode;
2682 inode = read_one_inode(root, key.objectid);
2687 from = ALIGN(i_size_read(inode),
2688 root->fs_info->sectorsize);
2689 drop_args.start = from;
2690 drop_args.end = (u64)-1;
2691 drop_args.drop_cache = true;
2692 ret = btrfs_drop_extents(wc->trans, root,
2696 inode_sub_bytes(inode,
2697 drop_args.bytes_found);
2698 /* Update the inode's nbytes. */
2699 ret = btrfs_update_inode(wc->trans,
2700 root, BTRFS_I(inode));
2707 ret = link_to_fixup_dir(wc->trans, root,
2708 path, key.objectid);
2713 if (wc->ignore_cur_inode)
2716 if (key.type == BTRFS_DIR_INDEX_KEY &&
2717 wc->stage == LOG_WALK_REPLAY_DIR_INDEX) {
2718 ret = replay_one_dir_item(wc->trans, root, path,
2724 if (wc->stage < LOG_WALK_REPLAY_ALL)
2727 /* these keys are simply copied */
2728 if (key.type == BTRFS_XATTR_ITEM_KEY) {
2729 ret = overwrite_item(wc->trans, root, path,
2733 } else if (key.type == BTRFS_INODE_REF_KEY ||
2734 key.type == BTRFS_INODE_EXTREF_KEY) {
2735 ret = add_inode_ref(wc->trans, root, log, path,
2737 if (ret && ret != -ENOENT)
2740 } else if (key.type == BTRFS_EXTENT_DATA_KEY) {
2741 ret = replay_one_extent(wc->trans, root, path,
2745 } else if (key.type == BTRFS_DIR_ITEM_KEY) {
2746 ret = replay_one_dir_item(wc->trans, root, path,
2752 btrfs_free_path(path);
2757 * Correctly adjust the reserved bytes occupied by a log tree extent buffer
2759 static void unaccount_log_buffer(struct btrfs_fs_info *fs_info, u64 start)
2761 struct btrfs_block_group *cache;
2763 cache = btrfs_lookup_block_group(fs_info, start);
2765 btrfs_err(fs_info, "unable to find block group for %llu", start);
2769 spin_lock(&cache->space_info->lock);
2770 spin_lock(&cache->lock);
2771 cache->reserved -= fs_info->nodesize;
2772 cache->space_info->bytes_reserved -= fs_info->nodesize;
2773 spin_unlock(&cache->lock);
2774 spin_unlock(&cache->space_info->lock);
2776 btrfs_put_block_group(cache);
2779 static noinline int walk_down_log_tree(struct btrfs_trans_handle *trans,
2780 struct btrfs_root *root,
2781 struct btrfs_path *path, int *level,
2782 struct walk_control *wc)
2784 struct btrfs_fs_info *fs_info = root->fs_info;
2787 struct extent_buffer *next;
2788 struct extent_buffer *cur;
2792 while (*level > 0) {
2793 struct btrfs_key first_key;
2795 cur = path->nodes[*level];
2797 WARN_ON(btrfs_header_level(cur) != *level);
2799 if (path->slots[*level] >=
2800 btrfs_header_nritems(cur))
2803 bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
2804 ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
2805 btrfs_node_key_to_cpu(cur, &first_key, path->slots[*level]);
2806 blocksize = fs_info->nodesize;
2808 next = btrfs_find_create_tree_block(fs_info, bytenr,
2809 btrfs_header_owner(cur),
2812 return PTR_ERR(next);
2815 ret = wc->process_func(root, next, wc, ptr_gen,
2818 free_extent_buffer(next);
2822 path->slots[*level]++;
2824 ret = btrfs_read_buffer(next, ptr_gen,
2825 *level - 1, &first_key);
2827 free_extent_buffer(next);
2832 btrfs_tree_lock(next);
2833 btrfs_clean_tree_block(next);
2834 btrfs_wait_tree_block_writeback(next);
2835 btrfs_tree_unlock(next);
2836 ret = btrfs_pin_reserved_extent(trans,
2839 free_extent_buffer(next);
2842 btrfs_redirty_list_add(
2843 trans->transaction, next);
2845 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &next->bflags))
2846 clear_extent_buffer_dirty(next);
2847 unaccount_log_buffer(fs_info, bytenr);
2850 free_extent_buffer(next);
2853 ret = btrfs_read_buffer(next, ptr_gen, *level - 1, &first_key);
2855 free_extent_buffer(next);
2859 if (path->nodes[*level-1])
2860 free_extent_buffer(path->nodes[*level-1]);
2861 path->nodes[*level-1] = next;
2862 *level = btrfs_header_level(next);
2863 path->slots[*level] = 0;
2866 path->slots[*level] = btrfs_header_nritems(path->nodes[*level]);
2872 static noinline int walk_up_log_tree(struct btrfs_trans_handle *trans,
2873 struct btrfs_root *root,
2874 struct btrfs_path *path, int *level,
2875 struct walk_control *wc)
2877 struct btrfs_fs_info *fs_info = root->fs_info;
2882 for (i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
2883 slot = path->slots[i];
2884 if (slot + 1 < btrfs_header_nritems(path->nodes[i])) {
2887 WARN_ON(*level == 0);
2890 ret = wc->process_func(root, path->nodes[*level], wc,
2891 btrfs_header_generation(path->nodes[*level]),
2897 struct extent_buffer *next;
2899 next = path->nodes[*level];
2902 btrfs_tree_lock(next);
2903 btrfs_clean_tree_block(next);
2904 btrfs_wait_tree_block_writeback(next);
2905 btrfs_tree_unlock(next);
2906 ret = btrfs_pin_reserved_extent(trans,
2907 path->nodes[*level]->start,
2908 path->nodes[*level]->len);
2911 btrfs_redirty_list_add(trans->transaction,
2914 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &next->bflags))
2915 clear_extent_buffer_dirty(next);
2917 unaccount_log_buffer(fs_info,
2918 path->nodes[*level]->start);
2921 free_extent_buffer(path->nodes[*level]);
2922 path->nodes[*level] = NULL;
2930 * drop the reference count on the tree rooted at 'snap'. This traverses
2931 * the tree freeing any blocks that have a ref count of zero after being
2934 static int walk_log_tree(struct btrfs_trans_handle *trans,
2935 struct btrfs_root *log, struct walk_control *wc)
2937 struct btrfs_fs_info *fs_info = log->fs_info;
2941 struct btrfs_path *path;
2944 path = btrfs_alloc_path();
2948 level = btrfs_header_level(log->node);
2950 path->nodes[level] = log->node;
2951 atomic_inc(&log->node->refs);
2952 path->slots[level] = 0;
2955 wret = walk_down_log_tree(trans, log, path, &level, wc);
2963 wret = walk_up_log_tree(trans, log, path, &level, wc);
2972 /* was the root node processed? if not, catch it here */
2973 if (path->nodes[orig_level]) {
2974 ret = wc->process_func(log, path->nodes[orig_level], wc,
2975 btrfs_header_generation(path->nodes[orig_level]),
2980 struct extent_buffer *next;
2982 next = path->nodes[orig_level];
2985 btrfs_tree_lock(next);
2986 btrfs_clean_tree_block(next);
2987 btrfs_wait_tree_block_writeback(next);
2988 btrfs_tree_unlock(next);
2989 ret = btrfs_pin_reserved_extent(trans,
2990 next->start, next->len);
2993 btrfs_redirty_list_add(trans->transaction, next);
2995 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &next->bflags))
2996 clear_extent_buffer_dirty(next);
2997 unaccount_log_buffer(fs_info, next->start);
3003 btrfs_free_path(path);
3008 * helper function to update the item for a given subvolumes log root
3009 * in the tree of log roots
3011 static int update_log_root(struct btrfs_trans_handle *trans,
3012 struct btrfs_root *log,
3013 struct btrfs_root_item *root_item)
3015 struct btrfs_fs_info *fs_info = log->fs_info;
3018 if (log->log_transid == 1) {
3019 /* insert root item on the first sync */
3020 ret = btrfs_insert_root(trans, fs_info->log_root_tree,
3021 &log->root_key, root_item);
3023 ret = btrfs_update_root(trans, fs_info->log_root_tree,
3024 &log->root_key, root_item);
3029 static void wait_log_commit(struct btrfs_root *root, int transid)
3032 int index = transid % 2;
3035 * we only allow two pending log transactions at a time,
3036 * so we know that if ours is more than 2 older than the
3037 * current transaction, we're done
3040 prepare_to_wait(&root->log_commit_wait[index],
3041 &wait, TASK_UNINTERRUPTIBLE);
3043 if (!(root->log_transid_committed < transid &&
3044 atomic_read(&root->log_commit[index])))
3047 mutex_unlock(&root->log_mutex);
3049 mutex_lock(&root->log_mutex);
3051 finish_wait(&root->log_commit_wait[index], &wait);
3054 static void wait_for_writer(struct btrfs_root *root)
3059 prepare_to_wait(&root->log_writer_wait, &wait,
3060 TASK_UNINTERRUPTIBLE);
3061 if (!atomic_read(&root->log_writers))
3064 mutex_unlock(&root->log_mutex);
3066 mutex_lock(&root->log_mutex);
3068 finish_wait(&root->log_writer_wait, &wait);
3071 static inline void btrfs_remove_log_ctx(struct btrfs_root *root,
3072 struct btrfs_log_ctx *ctx)
3074 mutex_lock(&root->log_mutex);
3075 list_del_init(&ctx->list);
3076 mutex_unlock(&root->log_mutex);
3080 * Invoked in log mutex context, or be sure there is no other task which
3081 * can access the list.
3083 static inline void btrfs_remove_all_log_ctxs(struct btrfs_root *root,
3084 int index, int error)
3086 struct btrfs_log_ctx *ctx;
3087 struct btrfs_log_ctx *safe;
3089 list_for_each_entry_safe(ctx, safe, &root->log_ctxs[index], list) {
3090 list_del_init(&ctx->list);
3091 ctx->log_ret = error;
3096 * btrfs_sync_log does sends a given tree log down to the disk and
3097 * updates the super blocks to record it. When this call is done,
3098 * you know that any inodes previously logged are safely on disk only
3101 * Any other return value means you need to call btrfs_commit_transaction.
3102 * Some of the edge cases for fsyncing directories that have had unlinks
3103 * or renames done in the past mean that sometimes the only safe
3104 * fsync is to commit the whole FS. When btrfs_sync_log returns -EAGAIN,
3105 * that has happened.
3107 int btrfs_sync_log(struct btrfs_trans_handle *trans,
3108 struct btrfs_root *root, struct btrfs_log_ctx *ctx)
3114 struct btrfs_fs_info *fs_info = root->fs_info;
3115 struct btrfs_root *log = root->log_root;
3116 struct btrfs_root *log_root_tree = fs_info->log_root_tree;
3117 struct btrfs_root_item new_root_item;
3118 int log_transid = 0;
3119 struct btrfs_log_ctx root_log_ctx;
3120 struct blk_plug plug;
3124 mutex_lock(&root->log_mutex);
3125 log_transid = ctx->log_transid;
3126 if (root->log_transid_committed >= log_transid) {
3127 mutex_unlock(&root->log_mutex);
3128 return ctx->log_ret;
3131 index1 = log_transid % 2;
3132 if (atomic_read(&root->log_commit[index1])) {
3133 wait_log_commit(root, log_transid);
3134 mutex_unlock(&root->log_mutex);
3135 return ctx->log_ret;
3137 ASSERT(log_transid == root->log_transid);
3138 atomic_set(&root->log_commit[index1], 1);
3140 /* wait for previous tree log sync to complete */
3141 if (atomic_read(&root->log_commit[(index1 + 1) % 2]))
3142 wait_log_commit(root, log_transid - 1);
3145 int batch = atomic_read(&root->log_batch);
3146 /* when we're on an ssd, just kick the log commit out */
3147 if (!btrfs_test_opt(fs_info, SSD) &&
3148 test_bit(BTRFS_ROOT_MULTI_LOG_TASKS, &root->state)) {
3149 mutex_unlock(&root->log_mutex);
3150 schedule_timeout_uninterruptible(1);
3151 mutex_lock(&root->log_mutex);
3153 wait_for_writer(root);
3154 if (batch == atomic_read(&root->log_batch))
3158 /* bail out if we need to do a full commit */
3159 if (btrfs_need_log_full_commit(trans)) {
3161 mutex_unlock(&root->log_mutex);
3165 if (log_transid % 2 == 0)
3166 mark = EXTENT_DIRTY;
3170 /* we start IO on all the marked extents here, but we don't actually
3171 * wait for them until later.
3173 blk_start_plug(&plug);
3174 ret = btrfs_write_marked_extents(fs_info, &log->dirty_log_pages, mark);
3176 * -EAGAIN happens when someone, e.g., a concurrent transaction
3177 * commit, writes a dirty extent in this tree-log commit. This
3178 * concurrent write will create a hole writing out the extents,
3179 * and we cannot proceed on a zoned filesystem, requiring
3180 * sequential writing. While we can bail out to a full commit
3181 * here, but we can continue hoping the concurrent writing fills
3184 if (ret == -EAGAIN && btrfs_is_zoned(fs_info))
3187 blk_finish_plug(&plug);
3188 btrfs_abort_transaction(trans, ret);
3189 btrfs_set_log_full_commit(trans);
3190 mutex_unlock(&root->log_mutex);
3195 * We _must_ update under the root->log_mutex in order to make sure we
3196 * have a consistent view of the log root we are trying to commit at
3199 * We _must_ copy this into a local copy, because we are not holding the
3200 * log_root_tree->log_mutex yet. This is important because when we
3201 * commit the log_root_tree we must have a consistent view of the
3202 * log_root_tree when we update the super block to point at the
3203 * log_root_tree bytenr. If we update the log_root_tree here we'll race
3204 * with the commit and possibly point at the new block which we may not
3207 btrfs_set_root_node(&log->root_item, log->node);
3208 memcpy(&new_root_item, &log->root_item, sizeof(new_root_item));
3210 root->log_transid++;
3211 log->log_transid = root->log_transid;
3212 root->log_start_pid = 0;
3214 * IO has been started, blocks of the log tree have WRITTEN flag set
3215 * in their headers. new modifications of the log will be written to
3216 * new positions. so it's safe to allow log writers to go in.
3218 mutex_unlock(&root->log_mutex);
3220 if (btrfs_is_zoned(fs_info)) {
3221 mutex_lock(&fs_info->tree_root->log_mutex);
3222 if (!log_root_tree->node) {
3223 ret = btrfs_alloc_log_tree_node(trans, log_root_tree);
3225 mutex_unlock(&fs_info->tree_root->log_mutex);
3229 mutex_unlock(&fs_info->tree_root->log_mutex);
3232 btrfs_init_log_ctx(&root_log_ctx, NULL);
3234 mutex_lock(&log_root_tree->log_mutex);
3236 index2 = log_root_tree->log_transid % 2;
3237 list_add_tail(&root_log_ctx.list, &log_root_tree->log_ctxs[index2]);
3238 root_log_ctx.log_transid = log_root_tree->log_transid;
3241 * Now we are safe to update the log_root_tree because we're under the
3242 * log_mutex, and we're a current writer so we're holding the commit
3243 * open until we drop the log_mutex.
3245 ret = update_log_root(trans, log, &new_root_item);
3247 if (!list_empty(&root_log_ctx.list))
3248 list_del_init(&root_log_ctx.list);
3250 blk_finish_plug(&plug);
3251 btrfs_set_log_full_commit(trans);
3253 if (ret != -ENOSPC) {
3254 btrfs_abort_transaction(trans, ret);
3255 mutex_unlock(&log_root_tree->log_mutex);
3258 btrfs_wait_tree_log_extents(log, mark);
3259 mutex_unlock(&log_root_tree->log_mutex);
3264 if (log_root_tree->log_transid_committed >= root_log_ctx.log_transid) {
3265 blk_finish_plug(&plug);
3266 list_del_init(&root_log_ctx.list);
3267 mutex_unlock(&log_root_tree->log_mutex);
3268 ret = root_log_ctx.log_ret;
3272 index2 = root_log_ctx.log_transid % 2;
3273 if (atomic_read(&log_root_tree->log_commit[index2])) {
3274 blk_finish_plug(&plug);
3275 ret = btrfs_wait_tree_log_extents(log, mark);
3276 wait_log_commit(log_root_tree,
3277 root_log_ctx.log_transid);
3278 mutex_unlock(&log_root_tree->log_mutex);
3280 ret = root_log_ctx.log_ret;
3283 ASSERT(root_log_ctx.log_transid == log_root_tree->log_transid);
3284 atomic_set(&log_root_tree->log_commit[index2], 1);
3286 if (atomic_read(&log_root_tree->log_commit[(index2 + 1) % 2])) {
3287 wait_log_commit(log_root_tree,
3288 root_log_ctx.log_transid - 1);
3292 * now that we've moved on to the tree of log tree roots,
3293 * check the full commit flag again
3295 if (btrfs_need_log_full_commit(trans)) {
3296 blk_finish_plug(&plug);
3297 btrfs_wait_tree_log_extents(log, mark);
3298 mutex_unlock(&log_root_tree->log_mutex);
3300 goto out_wake_log_root;
3303 ret = btrfs_write_marked_extents(fs_info,
3304 &log_root_tree->dirty_log_pages,
3305 EXTENT_DIRTY | EXTENT_NEW);
3306 blk_finish_plug(&plug);
3308 * As described above, -EAGAIN indicates a hole in the extents. We
3309 * cannot wait for these write outs since the waiting cause a
3310 * deadlock. Bail out to the full commit instead.
3312 if (ret == -EAGAIN && btrfs_is_zoned(fs_info)) {
3313 btrfs_set_log_full_commit(trans);
3314 btrfs_wait_tree_log_extents(log, mark);
3315 mutex_unlock(&log_root_tree->log_mutex);
3316 goto out_wake_log_root;
3318 btrfs_set_log_full_commit(trans);
3319 btrfs_abort_transaction(trans, ret);
3320 mutex_unlock(&log_root_tree->log_mutex);
3321 goto out_wake_log_root;
3323 ret = btrfs_wait_tree_log_extents(log, mark);
3325 ret = btrfs_wait_tree_log_extents(log_root_tree,
3326 EXTENT_NEW | EXTENT_DIRTY);
3328 btrfs_set_log_full_commit(trans);
3329 mutex_unlock(&log_root_tree->log_mutex);
3330 goto out_wake_log_root;
3333 log_root_start = log_root_tree->node->start;
3334 log_root_level = btrfs_header_level(log_root_tree->node);
3335 log_root_tree->log_transid++;
3336 mutex_unlock(&log_root_tree->log_mutex);
3339 * Here we are guaranteed that nobody is going to write the superblock
3340 * for the current transaction before us and that neither we do write
3341 * our superblock before the previous transaction finishes its commit
3342 * and writes its superblock, because:
3344 * 1) We are holding a handle on the current transaction, so no body
3345 * can commit it until we release the handle;
3347 * 2) Before writing our superblock we acquire the tree_log_mutex, so
3348 * if the previous transaction is still committing, and hasn't yet
3349 * written its superblock, we wait for it to do it, because a
3350 * transaction commit acquires the tree_log_mutex when the commit
3351 * begins and releases it only after writing its superblock.
3353 mutex_lock(&fs_info->tree_log_mutex);
3356 * The previous transaction writeout phase could have failed, and thus
3357 * marked the fs in an error state. We must not commit here, as we
3358 * could have updated our generation in the super_for_commit and
3359 * writing the super here would result in transid mismatches. If there
3360 * is an error here just bail.
3362 if (BTRFS_FS_ERROR(fs_info)) {
3364 btrfs_set_log_full_commit(trans);
3365 btrfs_abort_transaction(trans, ret);
3366 mutex_unlock(&fs_info->tree_log_mutex);
3367 goto out_wake_log_root;
3370 btrfs_set_super_log_root(fs_info->super_for_commit, log_root_start);
3371 btrfs_set_super_log_root_level(fs_info->super_for_commit, log_root_level);
3372 ret = write_all_supers(fs_info, 1);
3373 mutex_unlock(&fs_info->tree_log_mutex);
3375 btrfs_set_log_full_commit(trans);
3376 btrfs_abort_transaction(trans, ret);
3377 goto out_wake_log_root;
3381 * We know there can only be one task here, since we have not yet set
3382 * root->log_commit[index1] to 0 and any task attempting to sync the
3383 * log must wait for the previous log transaction to commit if it's
3384 * still in progress or wait for the current log transaction commit if
3385 * someone else already started it. We use <= and not < because the
3386 * first log transaction has an ID of 0.
3388 ASSERT(root->last_log_commit <= log_transid);
3389 root->last_log_commit = log_transid;
3392 mutex_lock(&log_root_tree->log_mutex);
3393 btrfs_remove_all_log_ctxs(log_root_tree, index2, ret);
3395 log_root_tree->log_transid_committed++;
3396 atomic_set(&log_root_tree->log_commit[index2], 0);
3397 mutex_unlock(&log_root_tree->log_mutex);
3400 * The barrier before waitqueue_active (in cond_wake_up) is needed so
3401 * all the updates above are seen by the woken threads. It might not be
3402 * necessary, but proving that seems to be hard.
3404 cond_wake_up(&log_root_tree->log_commit_wait[index2]);
3406 mutex_lock(&root->log_mutex);
3407 btrfs_remove_all_log_ctxs(root, index1, ret);
3408 root->log_transid_committed++;
3409 atomic_set(&root->log_commit[index1], 0);
3410 mutex_unlock(&root->log_mutex);
3413 * The barrier before waitqueue_active (in cond_wake_up) is needed so
3414 * all the updates above are seen by the woken threads. It might not be
3415 * necessary, but proving that seems to be hard.
3417 cond_wake_up(&root->log_commit_wait[index1]);
3421 static void free_log_tree(struct btrfs_trans_handle *trans,
3422 struct btrfs_root *log)
3425 struct walk_control wc = {
3427 .process_func = process_one_buffer
3431 ret = walk_log_tree(trans, log, &wc);
3434 btrfs_abort_transaction(trans, ret);
3436 btrfs_handle_fs_error(log->fs_info, ret, NULL);
3440 clear_extent_bits(&log->dirty_log_pages, 0, (u64)-1,
3441 EXTENT_DIRTY | EXTENT_NEW | EXTENT_NEED_WAIT);
3442 extent_io_tree_release(&log->log_csum_range);
3444 btrfs_put_root(log);
3448 * free all the extents used by the tree log. This should be called
3449 * at commit time of the full transaction
3451 int btrfs_free_log(struct btrfs_trans_handle *trans, struct btrfs_root *root)
3453 if (root->log_root) {
3454 free_log_tree(trans, root->log_root);
3455 root->log_root = NULL;
3456 clear_bit(BTRFS_ROOT_HAS_LOG_TREE, &root->state);
3461 int btrfs_free_log_root_tree(struct btrfs_trans_handle *trans,
3462 struct btrfs_fs_info *fs_info)
3464 if (fs_info->log_root_tree) {
3465 free_log_tree(trans, fs_info->log_root_tree);
3466 fs_info->log_root_tree = NULL;
3467 clear_bit(BTRFS_ROOT_HAS_LOG_TREE, &fs_info->tree_root->state);
3473 * Check if an inode was logged in the current transaction. This may often
3474 * return some false positives, because logged_trans is an in memory only field,
3475 * not persisted anywhere. This is meant to be used in contexts where a false
3476 * positive has no functional consequences.
3478 static bool inode_logged(struct btrfs_trans_handle *trans,
3479 struct btrfs_inode *inode)
3481 if (inode->logged_trans == trans->transid)
3484 if (!test_bit(BTRFS_ROOT_HAS_LOG_TREE, &inode->root->state))
3488 * The inode's logged_trans is always 0 when we load it (because it is
3489 * not persisted in the inode item or elsewhere). So if it is 0, the
3490 * inode was last modified in the current transaction then the inode may
3491 * have been logged before in the current transaction, then evicted and
3492 * loaded again in the current transaction - or may have never been logged
3493 * in the current transaction, but since we can not be sure, we have to
3494 * assume it was, otherwise our callers can leave an inconsistent log.
3496 if (inode->logged_trans == 0 &&
3497 inode->last_trans == trans->transid &&
3498 !test_bit(BTRFS_FS_LOG_RECOVERING, &trans->fs_info->flags))
3505 * If both a file and directory are logged, and unlinks or renames are
3506 * mixed in, we have a few interesting corners:
3508 * create file X in dir Y
3509 * link file X to X.link in dir Y
3511 * unlink file X but leave X.link
3514 * After a crash we would expect only X.link to exist. But file X
3515 * didn't get fsync'd again so the log has back refs for X and X.link.
3517 * We solve this by removing directory entries and inode backrefs from the
3518 * log when a file that was logged in the current transaction is
3519 * unlinked. Any later fsync will include the updated log entries, and
3520 * we'll be able to reconstruct the proper directory items from backrefs.
3522 * This optimizations allows us to avoid relogging the entire inode
3523 * or the entire directory.
3525 void btrfs_del_dir_entries_in_log(struct btrfs_trans_handle *trans,
3526 struct btrfs_root *root,
3527 const char *name, int name_len,
3528 struct btrfs_inode *dir, u64 index)
3530 struct btrfs_root *log;
3531 struct btrfs_dir_item *di;
3532 struct btrfs_path *path;
3535 u64 dir_ino = btrfs_ino(dir);
3537 if (!inode_logged(trans, dir))
3540 ret = join_running_log_trans(root);
3544 mutex_lock(&dir->log_mutex);
3546 log = root->log_root;
3547 path = btrfs_alloc_path();
3553 di = btrfs_lookup_dir_item(trans, log, path, dir_ino,
3554 name, name_len, -1);
3560 ret = btrfs_delete_one_dir_name(trans, log, path, di);
3566 btrfs_release_path(path);
3567 di = btrfs_lookup_dir_index_item(trans, log, path, dir_ino,
3568 index, name, name_len, -1);
3574 ret = btrfs_delete_one_dir_name(trans, log, path, di);
3582 * We do not need to update the size field of the directory's inode item
3583 * because on log replay we update the field to reflect all existing
3584 * entries in the directory (see overwrite_item()).
3587 btrfs_free_path(path);
3589 mutex_unlock(&dir->log_mutex);
3591 btrfs_set_log_full_commit(trans);
3592 btrfs_end_log_trans(root);
3595 /* see comments for btrfs_del_dir_entries_in_log */
3596 void btrfs_del_inode_ref_in_log(struct btrfs_trans_handle *trans,
3597 struct btrfs_root *root,
3598 const char *name, int name_len,
3599 struct btrfs_inode *inode, u64 dirid)
3601 struct btrfs_root *log;
3605 if (!inode_logged(trans, inode))
3608 ret = join_running_log_trans(root);
3611 log = root->log_root;
3612 mutex_lock(&inode->log_mutex);
3614 ret = btrfs_del_inode_ref(trans, log, name, name_len, btrfs_ino(inode),
3616 mutex_unlock(&inode->log_mutex);
3617 if (ret < 0 && ret != -ENOENT)
3618 btrfs_set_log_full_commit(trans);
3619 btrfs_end_log_trans(root);
3623 * creates a range item in the log for 'dirid'. first_offset and
3624 * last_offset tell us which parts of the key space the log should
3625 * be considered authoritative for.
3627 static noinline int insert_dir_log_key(struct btrfs_trans_handle *trans,
3628 struct btrfs_root *log,
3629 struct btrfs_path *path,
3630 int key_type, u64 dirid,
3631 u64 first_offset, u64 last_offset)
3634 struct btrfs_key key;
3635 struct btrfs_dir_log_item *item;
3637 key.objectid = dirid;
3638 key.offset = first_offset;
3639 if (key_type == BTRFS_DIR_ITEM_KEY)
3640 key.type = BTRFS_DIR_LOG_ITEM_KEY;
3642 key.type = BTRFS_DIR_LOG_INDEX_KEY;
3643 ret = btrfs_insert_empty_item(trans, log, path, &key, sizeof(*item));
3647 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
3648 struct btrfs_dir_log_item);
3649 btrfs_set_dir_log_end(path->nodes[0], item, last_offset);
3650 btrfs_mark_buffer_dirty(path->nodes[0]);
3651 btrfs_release_path(path);
3655 static int flush_dir_items_batch(struct btrfs_trans_handle *trans,
3656 struct btrfs_root *log,
3657 struct extent_buffer *src,
3658 struct btrfs_path *dst_path,
3662 char *ins_data = NULL;
3663 struct btrfs_item_batch batch;
3664 struct extent_buffer *dst;
3665 unsigned long src_offset;
3666 unsigned long dst_offset;
3667 struct btrfs_key key;
3676 btrfs_item_key_to_cpu(src, &key, start_slot);
3677 item_size = btrfs_item_size_nr(src, start_slot);
3679 batch.data_sizes = &item_size;
3680 batch.total_data_size = item_size;
3682 struct btrfs_key *ins_keys;
3685 ins_data = kmalloc(count * sizeof(u32) +
3686 count * sizeof(struct btrfs_key), GFP_NOFS);
3690 ins_sizes = (u32 *)ins_data;
3691 ins_keys = (struct btrfs_key *)(ins_data + count * sizeof(u32));
3692 batch.keys = ins_keys;
3693 batch.data_sizes = ins_sizes;
3694 batch.total_data_size = 0;
3696 for (i = 0; i < count; i++) {
3697 const int slot = start_slot + i;
3699 btrfs_item_key_to_cpu(src, &ins_keys[i], slot);
3700 ins_sizes[i] = btrfs_item_size_nr(src, slot);
3701 batch.total_data_size += ins_sizes[i];
3705 ret = btrfs_insert_empty_items(trans, log, dst_path, &batch);
3709 dst = dst_path->nodes[0];
3711 * Copy all the items in bulk, in a single copy operation. Item data is
3712 * organized such that it's placed at the end of a leaf and from right
3713 * to left. For example, the data for the second item ends at an offset
3714 * that matches the offset where the data for the first item starts, the
3715 * data for the third item ends at an offset that matches the offset
3716 * where the data of the second items starts, and so on.
3717 * Therefore our source and destination start offsets for copy match the
3718 * offsets of the last items (highest slots).
3720 dst_offset = btrfs_item_ptr_offset(dst, dst_path->slots[0] + count - 1);
3721 src_offset = btrfs_item_ptr_offset(src, start_slot + count - 1);
3722 copy_extent_buffer(dst, src, dst_offset, src_offset, batch.total_data_size);
3723 btrfs_release_path(dst_path);
3730 static int process_dir_items_leaf(struct btrfs_trans_handle *trans,
3731 struct btrfs_inode *inode,
3732 struct btrfs_path *path,
3733 struct btrfs_path *dst_path,
3735 struct btrfs_log_ctx *ctx)
3737 struct btrfs_root *log = inode->root->log_root;
3738 struct extent_buffer *src = path->nodes[0];
3739 const int nritems = btrfs_header_nritems(src);
3740 const u64 ino = btrfs_ino(inode);
3741 const bool inode_logged_before = inode_logged(trans, inode);
3742 u64 last_logged_key_offset;
3743 bool last_found = false;
3744 int batch_start = 0;
3748 if (key_type == BTRFS_DIR_ITEM_KEY)
3749 last_logged_key_offset = inode->last_dir_item_offset;
3751 last_logged_key_offset = inode->last_dir_index_offset;
3753 for (i = path->slots[0]; i < nritems; i++) {
3754 struct btrfs_key key;
3757 btrfs_item_key_to_cpu(src, &key, i);
3759 if (key.objectid != ino || key.type != key_type) {
3764 ctx->last_dir_item_offset = key.offset;
3766 * We must make sure that when we log a directory entry, the
3767 * corresponding inode, after log replay, has a matching link
3768 * count. For example:
3774 * xfs_io -c "fsync" mydir
3776 * <mount fs and log replay>
3778 * Would result in a fsync log that when replayed, our file inode
3779 * would have a link count of 1, but we get two directory entries
3780 * pointing to the same inode. After removing one of the names,
3781 * it would not be possible to remove the other name, which
3782 * resulted always in stale file handle errors, and would not be
3783 * possible to rmdir the parent directory, since its i_size could
3784 * never be decremented to the value BTRFS_EMPTY_DIR_SIZE,
3785 * resulting in -ENOTEMPTY errors.
3787 if (!ctx->log_new_dentries) {
3788 struct btrfs_dir_item *di;
3789 struct btrfs_key di_key;
3791 di = btrfs_item_ptr(src, i, struct btrfs_dir_item);
3792 btrfs_dir_item_key_to_cpu(src, di, &di_key);
3793 if ((btrfs_dir_transid(src, di) == trans->transid ||
3794 btrfs_dir_type(src, di) == BTRFS_FT_DIR) &&
3795 di_key.type != BTRFS_ROOT_ITEM_KEY)
3796 ctx->log_new_dentries = true;
3799 if (!inode_logged_before)
3803 * If we were logged before and have logged dir items, we can skip
3804 * checking if any item with a key offset larger than the last one
3805 * we logged is in the log tree, saving time and avoiding adding
3806 * contention on the log tree.
3808 if (key.offset > last_logged_key_offset)
3811 * Check if the key was already logged before. If not we can add
3812 * it to a batch for bulk insertion.
3814 ret = btrfs_search_slot(NULL, log, &key, dst_path, 0, 0);
3817 } else if (ret > 0) {
3818 btrfs_release_path(dst_path);
3823 * Item exists in the log. Overwrite the item in the log if it
3824 * has different content or do nothing if it has exactly the same
3825 * content. And then flush the current batch if any - do it after
3826 * overwriting the current item, or we would deadlock otherwise,
3827 * since we are holding a path for the existing item.
3829 ret = do_overwrite_item(trans, log, dst_path, src, i, &key);
3833 if (batch_size > 0) {
3834 ret = flush_dir_items_batch(trans, log, src, dst_path,
3835 batch_start, batch_size);
3842 if (batch_size == 0)
3847 if (batch_size > 0) {
3850 ret = flush_dir_items_batch(trans, log, src, dst_path,
3851 batch_start, batch_size);
3856 return last_found ? 1 : 0;
3860 * log all the items included in the current transaction for a given
3861 * directory. This also creates the range items in the log tree required
3862 * to replay anything deleted before the fsync
3864 static noinline int log_dir_items(struct btrfs_trans_handle *trans,
3865 struct btrfs_inode *inode,
3866 struct btrfs_path *path,
3867 struct btrfs_path *dst_path, int key_type,
3868 struct btrfs_log_ctx *ctx,
3869 u64 min_offset, u64 *last_offset_ret)
3871 struct btrfs_key min_key;
3872 struct btrfs_root *root = inode->root;
3873 struct btrfs_root *log = root->log_root;
3876 u64 first_offset = min_offset;
3877 u64 last_offset = (u64)-1;
3878 u64 ino = btrfs_ino(inode);
3880 min_key.objectid = ino;
3881 min_key.type = key_type;
3882 min_key.offset = min_offset;
3884 ret = btrfs_search_forward(root, &min_key, path, trans->transid);
3887 * we didn't find anything from this transaction, see if there
3888 * is anything at all
3890 if (ret != 0 || min_key.objectid != ino || min_key.type != key_type) {
3891 min_key.objectid = ino;
3892 min_key.type = key_type;
3893 min_key.offset = (u64)-1;
3894 btrfs_release_path(path);
3895 ret = btrfs_search_slot(NULL, root, &min_key, path, 0, 0);
3897 btrfs_release_path(path);
3900 ret = btrfs_previous_item(root, path, ino, key_type);
3902 /* if ret == 0 there are items for this type,
3903 * create a range to tell us the last key of this type.
3904 * otherwise, there are no items in this directory after
3905 * *min_offset, and we create a range to indicate that.
3908 struct btrfs_key tmp;
3909 btrfs_item_key_to_cpu(path->nodes[0], &tmp,
3911 if (key_type == tmp.type)
3912 first_offset = max(min_offset, tmp.offset) + 1;
3917 /* go backward to find any previous key */
3918 ret = btrfs_previous_item(root, path, ino, key_type);
3920 struct btrfs_key tmp;
3921 btrfs_item_key_to_cpu(path->nodes[0], &tmp, path->slots[0]);
3922 if (key_type == tmp.type) {
3923 first_offset = tmp.offset;
3924 ret = overwrite_item(trans, log, dst_path,
3925 path->nodes[0], path->slots[0],
3933 btrfs_release_path(path);
3936 * Find the first key from this transaction again. See the note for
3937 * log_new_dir_dentries, if we're logging a directory recursively we
3938 * won't be holding its i_mutex, which means we can modify the directory
3939 * while we're logging it. If we remove an entry between our first
3940 * search and this search we'll not find the key again and can just
3944 ret = btrfs_search_slot(NULL, root, &min_key, path, 0, 0);
3949 * we have a block from this transaction, log every item in it
3950 * from our directory
3953 ret = process_dir_items_leaf(trans, inode, path, dst_path,
3960 path->slots[0] = btrfs_header_nritems(path->nodes[0]);
3963 * look ahead to the next item and see if it is also
3964 * from this directory and from this transaction
3966 ret = btrfs_next_leaf(root, path);
3969 last_offset = (u64)-1;
3974 btrfs_item_key_to_cpu(path->nodes[0], &min_key, path->slots[0]);
3975 if (min_key.objectid != ino || min_key.type != key_type) {
3976 last_offset = (u64)-1;
3979 if (btrfs_header_generation(path->nodes[0]) != trans->transid) {
3980 ret = overwrite_item(trans, log, dst_path,
3981 path->nodes[0], path->slots[0],
3986 last_offset = min_key.offset;
3989 if (need_resched()) {
3990 btrfs_release_path(path);
3996 btrfs_release_path(path);
3997 btrfs_release_path(dst_path);
4000 *last_offset_ret = last_offset;
4002 * insert the log range keys to indicate where the log
4005 ret = insert_dir_log_key(trans, log, path, key_type,
4006 ino, first_offset, last_offset);
4014 * logging directories is very similar to logging inodes, We find all the items
4015 * from the current transaction and write them to the log.
4017 * The recovery code scans the directory in the subvolume, and if it finds a
4018 * key in the range logged that is not present in the log tree, then it means
4019 * that dir entry was unlinked during the transaction.
4021 * In order for that scan to work, we must include one key smaller than
4022 * the smallest logged by this transaction and one key larger than the largest
4023 * key logged by this transaction.
4025 static noinline int log_directory_changes(struct btrfs_trans_handle *trans,
4026 struct btrfs_inode *inode,
4027 struct btrfs_path *path,
4028 struct btrfs_path *dst_path,
4029 struct btrfs_log_ctx *ctx)
4034 int key_type = BTRFS_DIR_ITEM_KEY;
4037 * If this is the first time we are being logged in the current
4038 * transaction, or we were logged before but the inode was evicted and
4039 * reloaded later, in which case its logged_trans is 0, reset the values
4040 * of the last logged key offsets. Note that we don't use the helper
4041 * function inode_logged() here - that is because the function returns
4042 * true after an inode eviction, assuming the worst case as it can not
4043 * know for sure if the inode was logged before. So we can not skip key
4044 * searches in the case the inode was evicted, because it may not have
4045 * been logged in this transaction and may have been logged in a past
4046 * transaction, so we need to reset the last dir item and index offsets
4049 if (inode->logged_trans != trans->transid) {
4050 inode->last_dir_item_offset = (u64)-1;
4051 inode->last_dir_index_offset = (u64)-1;
4056 if (key_type == BTRFS_DIR_ITEM_KEY)
4057 ctx->last_dir_item_offset = inode->last_dir_item_offset;
4059 ctx->last_dir_item_offset = inode->last_dir_index_offset;
4062 ret = log_dir_items(trans, inode, path, dst_path, key_type,
4063 ctx, min_key, &max_key);
4066 if (max_key == (u64)-1)
4068 min_key = max_key + 1;
4071 if (key_type == BTRFS_DIR_ITEM_KEY) {
4072 inode->last_dir_item_offset = ctx->last_dir_item_offset;
4073 key_type = BTRFS_DIR_INDEX_KEY;
4076 inode->last_dir_index_offset = ctx->last_dir_item_offset;
4082 * a helper function to drop items from the log before we relog an
4083 * inode. max_key_type indicates the highest item type to remove.
4084 * This cannot be run for file data extents because it does not
4085 * free the extents they point to.
4087 static int drop_inode_items(struct btrfs_trans_handle *trans,
4088 struct btrfs_root *log,
4089 struct btrfs_path *path,
4090 struct btrfs_inode *inode,
4094 struct btrfs_key key;
4095 struct btrfs_key found_key;
4098 if (!inode_logged(trans, inode))
4101 key.objectid = btrfs_ino(inode);
4102 key.type = max_key_type;
4103 key.offset = (u64)-1;
4106 ret = btrfs_search_slot(trans, log, &key, path, -1, 1);
4107 BUG_ON(ret == 0); /* Logic error */
4111 if (path->slots[0] == 0)
4115 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
4118 if (found_key.objectid != key.objectid)
4121 found_key.offset = 0;
4123 ret = btrfs_bin_search(path->nodes[0], &found_key, &start_slot);
4127 ret = btrfs_del_items(trans, log, path, start_slot,
4128 path->slots[0] - start_slot + 1);
4130 * If start slot isn't 0 then we don't need to re-search, we've
4131 * found the last guy with the objectid in this tree.
4133 if (ret || start_slot != 0)
4135 btrfs_release_path(path);
4137 btrfs_release_path(path);
4143 static int truncate_inode_items(struct btrfs_trans_handle *trans,
4144 struct btrfs_root *log_root,
4145 struct btrfs_inode *inode,
4146 u64 new_size, u32 min_type)
4151 ret = btrfs_truncate_inode_items(trans, log_root, inode,
4152 new_size, min_type, NULL);
4153 } while (ret == -EAGAIN);
4158 static void fill_inode_item(struct btrfs_trans_handle *trans,
4159 struct extent_buffer *leaf,
4160 struct btrfs_inode_item *item,
4161 struct inode *inode, int log_inode_only,
4164 struct btrfs_map_token token;
4167 btrfs_init_map_token(&token, leaf);
4169 if (log_inode_only) {
4170 /* set the generation to zero so the recover code
4171 * can tell the difference between an logging
4172 * just to say 'this inode exists' and a logging
4173 * to say 'update this inode with these values'
4175 btrfs_set_token_inode_generation(&token, item, 0);
4176 btrfs_set_token_inode_size(&token, item, logged_isize);
4178 btrfs_set_token_inode_generation(&token, item,
4179 BTRFS_I(inode)->generation);
4180 btrfs_set_token_inode_size(&token, item, inode->i_size);
4183 btrfs_set_token_inode_uid(&token, item, i_uid_read(inode));
4184 btrfs_set_token_inode_gid(&token, item, i_gid_read(inode));
4185 btrfs_set_token_inode_mode(&token, item, inode->i_mode);
4186 btrfs_set_token_inode_nlink(&token, item, inode->i_nlink);
4188 btrfs_set_token_timespec_sec(&token, &item->atime,
4189 inode->i_atime.tv_sec);
4190 btrfs_set_token_timespec_nsec(&token, &item->atime,
4191 inode->i_atime.tv_nsec);
4193 btrfs_set_token_timespec_sec(&token, &item->mtime,
4194 inode->i_mtime.tv_sec);
4195 btrfs_set_token_timespec_nsec(&token, &item->mtime,
4196 inode->i_mtime.tv_nsec);
4198 btrfs_set_token_timespec_sec(&token, &item->ctime,
4199 inode->i_ctime.tv_sec);
4200 btrfs_set_token_timespec_nsec(&token, &item->ctime,
4201 inode->i_ctime.tv_nsec);
4204 * We do not need to set the nbytes field, in fact during a fast fsync
4205 * its value may not even be correct, since a fast fsync does not wait
4206 * for ordered extent completion, which is where we update nbytes, it
4207 * only waits for writeback to complete. During log replay as we find
4208 * file extent items and replay them, we adjust the nbytes field of the
4209 * inode item in subvolume tree as needed (see overwrite_item()).
4212 btrfs_set_token_inode_sequence(&token, item, inode_peek_iversion(inode));
4213 btrfs_set_token_inode_transid(&token, item, trans->transid);
4214 btrfs_set_token_inode_rdev(&token, item, inode->i_rdev);
4215 flags = btrfs_inode_combine_flags(BTRFS_I(inode)->flags,
4216 BTRFS_I(inode)->ro_flags);
4217 btrfs_set_token_inode_flags(&token, item, flags);
4218 btrfs_set_token_inode_block_group(&token, item, 0);
4221 static int log_inode_item(struct btrfs_trans_handle *trans,
4222 struct btrfs_root *log, struct btrfs_path *path,
4223 struct btrfs_inode *inode, bool inode_item_dropped)
4225 struct btrfs_inode_item *inode_item;
4229 * If we are doing a fast fsync and the inode was logged before in the
4230 * current transaction, then we know the inode was previously logged and
4231 * it exists in the log tree. For performance reasons, in this case use
4232 * btrfs_search_slot() directly with ins_len set to 0 so that we never
4233 * attempt a write lock on the leaf's parent, which adds unnecessary lock
4234 * contention in case there are concurrent fsyncs for other inodes of the
4235 * same subvolume. Using btrfs_insert_empty_item() when the inode item
4236 * already exists can also result in unnecessarily splitting a leaf.
4238 if (!inode_item_dropped && inode->logged_trans == trans->transid) {
4239 ret = btrfs_search_slot(trans, log, &inode->location, path, 0, 1);
4245 * This means it is the first fsync in the current transaction,
4246 * so the inode item is not in the log and we need to insert it.
4247 * We can never get -EEXIST because we are only called for a fast
4248 * fsync and in case an inode eviction happens after the inode was
4249 * logged before in the current transaction, when we load again
4250 * the inode, we set BTRFS_INODE_NEEDS_FULL_SYNC on its runtime
4251 * flags and set ->logged_trans to 0.
4253 ret = btrfs_insert_empty_item(trans, log, path, &inode->location,
4254 sizeof(*inode_item));
4255 ASSERT(ret != -EEXIST);
4259 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
4260 struct btrfs_inode_item);
4261 fill_inode_item(trans, path->nodes[0], inode_item, &inode->vfs_inode,
4263 btrfs_release_path(path);
4267 static int log_csums(struct btrfs_trans_handle *trans,
4268 struct btrfs_inode *inode,
4269 struct btrfs_root *log_root,
4270 struct btrfs_ordered_sum *sums)
4272 const u64 lock_end = sums->bytenr + sums->len - 1;
4273 struct extent_state *cached_state = NULL;
4277 * If this inode was not used for reflink operations in the current
4278 * transaction with new extents, then do the fast path, no need to
4279 * worry about logging checksum items with overlapping ranges.
4281 if (inode->last_reflink_trans < trans->transid)
4282 return btrfs_csum_file_blocks(trans, log_root, sums);
4285 * Serialize logging for checksums. This is to avoid racing with the
4286 * same checksum being logged by another task that is logging another
4287 * file which happens to refer to the same extent as well. Such races
4288 * can leave checksum items in the log with overlapping ranges.
4290 ret = lock_extent_bits(&log_root->log_csum_range, sums->bytenr,
4291 lock_end, &cached_state);
4295 * Due to extent cloning, we might have logged a csum item that covers a
4296 * subrange of a cloned extent, and later we can end up logging a csum
4297 * item for a larger subrange of the same extent or the entire range.
4298 * This would leave csum items in the log tree that cover the same range
4299 * and break the searches for checksums in the log tree, resulting in
4300 * some checksums missing in the fs/subvolume tree. So just delete (or
4301 * trim and adjust) any existing csum items in the log for this range.
4303 ret = btrfs_del_csums(trans, log_root, sums->bytenr, sums->len);
4305 ret = btrfs_csum_file_blocks(trans, log_root, sums);
4307 unlock_extent_cached(&log_root->log_csum_range, sums->bytenr, lock_end,
4313 static noinline int copy_items(struct btrfs_trans_handle *trans,
4314 struct btrfs_inode *inode,
4315 struct btrfs_path *dst_path,
4316 struct btrfs_path *src_path,
4317 int start_slot, int nr, int inode_only,
4320 struct btrfs_fs_info *fs_info = trans->fs_info;
4321 unsigned long src_offset;
4322 unsigned long dst_offset;
4323 struct btrfs_root *log = inode->root->log_root;
4324 struct btrfs_file_extent_item *extent;
4325 struct btrfs_inode_item *inode_item;
4326 struct extent_buffer *src = src_path->nodes[0];
4328 struct btrfs_key *ins_keys;
4330 struct btrfs_item_batch batch;
4333 struct list_head ordered_sums;
4334 int skip_csum = inode->flags & BTRFS_INODE_NODATASUM;
4336 INIT_LIST_HEAD(&ordered_sums);
4338 ins_data = kmalloc(nr * sizeof(struct btrfs_key) +
4339 nr * sizeof(u32), GFP_NOFS);
4343 ins_sizes = (u32 *)ins_data;
4344 ins_keys = (struct btrfs_key *)(ins_data + nr * sizeof(u32));
4345 batch.keys = ins_keys;
4346 batch.data_sizes = ins_sizes;
4347 batch.total_data_size = 0;
4350 for (i = 0; i < nr; i++) {
4351 ins_sizes[i] = btrfs_item_size_nr(src, i + start_slot);
4352 batch.total_data_size += ins_sizes[i];
4353 btrfs_item_key_to_cpu(src, ins_keys + i, i + start_slot);
4355 ret = btrfs_insert_empty_items(trans, log, dst_path, &batch);
4361 for (i = 0; i < nr; i++, dst_path->slots[0]++) {
4362 dst_offset = btrfs_item_ptr_offset(dst_path->nodes[0],
4363 dst_path->slots[0]);
4365 src_offset = btrfs_item_ptr_offset(src, start_slot + i);
4367 if (ins_keys[i].type == BTRFS_INODE_ITEM_KEY) {
4368 inode_item = btrfs_item_ptr(dst_path->nodes[0],
4370 struct btrfs_inode_item);
4371 fill_inode_item(trans, dst_path->nodes[0], inode_item,
4373 inode_only == LOG_INODE_EXISTS,
4376 copy_extent_buffer(dst_path->nodes[0], src, dst_offset,
4377 src_offset, ins_sizes[i]);
4380 /* take a reference on file data extents so that truncates
4381 * or deletes of this inode don't have to relog the inode
4384 if (ins_keys[i].type == BTRFS_EXTENT_DATA_KEY &&
4387 extent = btrfs_item_ptr(src, start_slot + i,
4388 struct btrfs_file_extent_item);
4390 if (btrfs_file_extent_generation(src, extent) < trans->transid)
4393 found_type = btrfs_file_extent_type(src, extent);
4394 if (found_type == BTRFS_FILE_EXTENT_REG) {
4396 ds = btrfs_file_extent_disk_bytenr(src,
4398 /* ds == 0 is a hole */
4402 dl = btrfs_file_extent_disk_num_bytes(src,
4404 cs = btrfs_file_extent_offset(src, extent);
4405 cl = btrfs_file_extent_num_bytes(src,
4407 if (btrfs_file_extent_compression(src,
4413 ret = btrfs_lookup_csums_range(
4415 ds + cs, ds + cs + cl - 1,
4423 btrfs_mark_buffer_dirty(dst_path->nodes[0]);
4424 btrfs_release_path(dst_path);
4428 * we have to do this after the loop above to avoid changing the
4429 * log tree while trying to change the log tree.
4431 while (!list_empty(&ordered_sums)) {
4432 struct btrfs_ordered_sum *sums = list_entry(ordered_sums.next,
4433 struct btrfs_ordered_sum,
4436 ret = log_csums(trans, inode, log, sums);
4437 list_del(&sums->list);
4444 static int extent_cmp(void *priv, const struct list_head *a,
4445 const struct list_head *b)
4447 const struct extent_map *em1, *em2;
4449 em1 = list_entry(a, struct extent_map, list);
4450 em2 = list_entry(b, struct extent_map, list);
4452 if (em1->start < em2->start)
4454 else if (em1->start > em2->start)
4459 static int log_extent_csums(struct btrfs_trans_handle *trans,
4460 struct btrfs_inode *inode,
4461 struct btrfs_root *log_root,
4462 const struct extent_map *em,
4463 struct btrfs_log_ctx *ctx)
4465 struct btrfs_ordered_extent *ordered;
4468 u64 mod_start = em->mod_start;
4469 u64 mod_len = em->mod_len;
4470 LIST_HEAD(ordered_sums);
4473 if (inode->flags & BTRFS_INODE_NODATASUM ||
4474 test_bit(EXTENT_FLAG_PREALLOC, &em->flags) ||
4475 em->block_start == EXTENT_MAP_HOLE)
4478 list_for_each_entry(ordered, &ctx->ordered_extents, log_list) {
4479 const u64 ordered_end = ordered->file_offset + ordered->num_bytes;
4480 const u64 mod_end = mod_start + mod_len;
4481 struct btrfs_ordered_sum *sums;
4486 if (ordered_end <= mod_start)
4488 if (mod_end <= ordered->file_offset)
4492 * We are going to copy all the csums on this ordered extent, so
4493 * go ahead and adjust mod_start and mod_len in case this ordered
4494 * extent has already been logged.
4496 if (ordered->file_offset > mod_start) {
4497 if (ordered_end >= mod_end)
4498 mod_len = ordered->file_offset - mod_start;
4500 * If we have this case
4502 * |--------- logged extent ---------|
4503 * |----- ordered extent ----|
4505 * Just don't mess with mod_start and mod_len, we'll
4506 * just end up logging more csums than we need and it
4510 if (ordered_end < mod_end) {
4511 mod_len = mod_end - ordered_end;
4512 mod_start = ordered_end;
4519 * To keep us from looping for the above case of an ordered
4520 * extent that falls inside of the logged extent.
4522 if (test_and_set_bit(BTRFS_ORDERED_LOGGED_CSUM, &ordered->flags))
4525 list_for_each_entry(sums, &ordered->list, list) {
4526 ret = log_csums(trans, inode, log_root, sums);
4532 /* We're done, found all csums in the ordered extents. */
4536 /* If we're compressed we have to save the entire range of csums. */
4537 if (em->compress_type) {
4539 csum_len = max(em->block_len, em->orig_block_len);
4541 csum_offset = mod_start - em->start;
4545 /* block start is already adjusted for the file extent offset. */
4546 ret = btrfs_lookup_csums_range(trans->fs_info->csum_root,
4547 em->block_start + csum_offset,
4548 em->block_start + csum_offset +
4549 csum_len - 1, &ordered_sums, 0);
4553 while (!list_empty(&ordered_sums)) {
4554 struct btrfs_ordered_sum *sums = list_entry(ordered_sums.next,
4555 struct btrfs_ordered_sum,
4558 ret = log_csums(trans, inode, log_root, sums);
4559 list_del(&sums->list);
4566 static int log_one_extent(struct btrfs_trans_handle *trans,
4567 struct btrfs_inode *inode,
4568 const struct extent_map *em,
4569 struct btrfs_path *path,
4570 struct btrfs_log_ctx *ctx)
4572 struct btrfs_drop_extents_args drop_args = { 0 };
4573 struct btrfs_root *log = inode->root->log_root;
4574 struct btrfs_file_extent_item *fi;
4575 struct extent_buffer *leaf;
4576 struct btrfs_map_token token;
4577 struct btrfs_key key;
4578 u64 extent_offset = em->start - em->orig_start;
4582 ret = log_extent_csums(trans, inode, log, em, ctx);
4587 * If this is the first time we are logging the inode in the current
4588 * transaction, we can avoid btrfs_drop_extents(), which is expensive
4589 * because it does a deletion search, which always acquires write locks
4590 * for extent buffers at levels 2, 1 and 0. This not only wastes time
4591 * but also adds significant contention in a log tree, since log trees
4592 * are small, with a root at level 2 or 3 at most, due to their short
4595 if (inode_logged(trans, inode)) {
4596 drop_args.path = path;
4597 drop_args.start = em->start;
4598 drop_args.end = em->start + em->len;
4599 drop_args.replace_extent = true;
4600 drop_args.extent_item_size = sizeof(*fi);
4601 ret = btrfs_drop_extents(trans, log, inode, &drop_args);
4606 if (!drop_args.extent_inserted) {
4607 key.objectid = btrfs_ino(inode);
4608 key.type = BTRFS_EXTENT_DATA_KEY;
4609 key.offset = em->start;
4611 ret = btrfs_insert_empty_item(trans, log, path, &key,
4616 leaf = path->nodes[0];
4617 btrfs_init_map_token(&token, leaf);
4618 fi = btrfs_item_ptr(leaf, path->slots[0],
4619 struct btrfs_file_extent_item);
4621 btrfs_set_token_file_extent_generation(&token, fi, trans->transid);
4622 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
4623 btrfs_set_token_file_extent_type(&token, fi,
4624 BTRFS_FILE_EXTENT_PREALLOC);
4626 btrfs_set_token_file_extent_type(&token, fi,
4627 BTRFS_FILE_EXTENT_REG);
4629 block_len = max(em->block_len, em->orig_block_len);
4630 if (em->compress_type != BTRFS_COMPRESS_NONE) {
4631 btrfs_set_token_file_extent_disk_bytenr(&token, fi,
4633 btrfs_set_token_file_extent_disk_num_bytes(&token, fi, block_len);
4634 } else if (em->block_start < EXTENT_MAP_LAST_BYTE) {
4635 btrfs_set_token_file_extent_disk_bytenr(&token, fi,
4638 btrfs_set_token_file_extent_disk_num_bytes(&token, fi, block_len);
4640 btrfs_set_token_file_extent_disk_bytenr(&token, fi, 0);
4641 btrfs_set_token_file_extent_disk_num_bytes(&token, fi, 0);
4644 btrfs_set_token_file_extent_offset(&token, fi, extent_offset);
4645 btrfs_set_token_file_extent_num_bytes(&token, fi, em->len);
4646 btrfs_set_token_file_extent_ram_bytes(&token, fi, em->ram_bytes);
4647 btrfs_set_token_file_extent_compression(&token, fi, em->compress_type);
4648 btrfs_set_token_file_extent_encryption(&token, fi, 0);
4649 btrfs_set_token_file_extent_other_encoding(&token, fi, 0);
4650 btrfs_mark_buffer_dirty(leaf);
4652 btrfs_release_path(path);
4658 * Log all prealloc extents beyond the inode's i_size to make sure we do not
4659 * lose them after doing a fast fsync and replaying the log. We scan the
4660 * subvolume's root instead of iterating the inode's extent map tree because
4661 * otherwise we can log incorrect extent items based on extent map conversion.
4662 * That can happen due to the fact that extent maps are merged when they
4663 * are not in the extent map tree's list of modified extents.
4665 static int btrfs_log_prealloc_extents(struct btrfs_trans_handle *trans,
4666 struct btrfs_inode *inode,
4667 struct btrfs_path *path)
4669 struct btrfs_root *root = inode->root;
4670 struct btrfs_key key;
4671 const u64 i_size = i_size_read(&inode->vfs_inode);
4672 const u64 ino = btrfs_ino(inode);
4673 struct btrfs_path *dst_path = NULL;
4674 bool dropped_extents = false;
4675 u64 truncate_offset = i_size;
4676 struct extent_buffer *leaf;
4682 if (!(inode->flags & BTRFS_INODE_PREALLOC))
4686 key.type = BTRFS_EXTENT_DATA_KEY;
4687 key.offset = i_size;
4688 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4693 * We must check if there is a prealloc extent that starts before the
4694 * i_size and crosses the i_size boundary. This is to ensure later we
4695 * truncate down to the end of that extent and not to the i_size, as
4696 * otherwise we end up losing part of the prealloc extent after a log
4697 * replay and with an implicit hole if there is another prealloc extent
4698 * that starts at an offset beyond i_size.
4700 ret = btrfs_previous_item(root, path, ino, BTRFS_EXTENT_DATA_KEY);
4705 struct btrfs_file_extent_item *ei;
4707 leaf = path->nodes[0];
4708 slot = path->slots[0];
4709 ei = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
4711 if (btrfs_file_extent_type(leaf, ei) ==
4712 BTRFS_FILE_EXTENT_PREALLOC) {
4715 btrfs_item_key_to_cpu(leaf, &key, slot);
4716 extent_end = key.offset +
4717 btrfs_file_extent_num_bytes(leaf, ei);
4719 if (extent_end > i_size)
4720 truncate_offset = extent_end;
4727 leaf = path->nodes[0];
4728 slot = path->slots[0];
4730 if (slot >= btrfs_header_nritems(leaf)) {
4732 ret = copy_items(trans, inode, dst_path, path,
4733 start_slot, ins_nr, 1, 0);
4738 ret = btrfs_next_leaf(root, path);
4748 btrfs_item_key_to_cpu(leaf, &key, slot);
4749 if (key.objectid > ino)
4751 if (WARN_ON_ONCE(key.objectid < ino) ||
4752 key.type < BTRFS_EXTENT_DATA_KEY ||
4753 key.offset < i_size) {
4757 if (!dropped_extents) {
4759 * Avoid logging extent items logged in past fsync calls
4760 * and leading to duplicate keys in the log tree.
4762 ret = truncate_inode_items(trans, root->log_root, inode,
4764 BTRFS_EXTENT_DATA_KEY);
4767 dropped_extents = true;
4774 dst_path = btrfs_alloc_path();
4782 ret = copy_items(trans, inode, dst_path, path,
4783 start_slot, ins_nr, 1, 0);
4785 btrfs_release_path(path);
4786 btrfs_free_path(dst_path);
4790 static int btrfs_log_changed_extents(struct btrfs_trans_handle *trans,
4791 struct btrfs_inode *inode,
4792 struct btrfs_path *path,
4793 struct btrfs_log_ctx *ctx)
4795 struct btrfs_ordered_extent *ordered;
4796 struct btrfs_ordered_extent *tmp;
4797 struct extent_map *em, *n;
4798 struct list_head extents;
4799 struct extent_map_tree *tree = &inode->extent_tree;
4803 INIT_LIST_HEAD(&extents);
4805 write_lock(&tree->lock);
4807 list_for_each_entry_safe(em, n, &tree->modified_extents, list) {
4808 list_del_init(&em->list);
4810 * Just an arbitrary number, this can be really CPU intensive
4811 * once we start getting a lot of extents, and really once we
4812 * have a bunch of extents we just want to commit since it will
4815 if (++num > 32768) {
4816 list_del_init(&tree->modified_extents);
4821 if (em->generation < trans->transid)
4824 /* We log prealloc extents beyond eof later. */
4825 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) &&
4826 em->start >= i_size_read(&inode->vfs_inode))
4829 /* Need a ref to keep it from getting evicted from cache */
4830 refcount_inc(&em->refs);
4831 set_bit(EXTENT_FLAG_LOGGING, &em->flags);
4832 list_add_tail(&em->list, &extents);
4836 list_sort(NULL, &extents, extent_cmp);
4838 while (!list_empty(&extents)) {
4839 em = list_entry(extents.next, struct extent_map, list);
4841 list_del_init(&em->list);
4844 * If we had an error we just need to delete everybody from our
4848 clear_em_logging(tree, em);
4849 free_extent_map(em);
4853 write_unlock(&tree->lock);
4855 ret = log_one_extent(trans, inode, em, path, ctx);
4856 write_lock(&tree->lock);
4857 clear_em_logging(tree, em);
4858 free_extent_map(em);
4860 WARN_ON(!list_empty(&extents));
4861 write_unlock(&tree->lock);
4863 btrfs_release_path(path);
4865 ret = btrfs_log_prealloc_extents(trans, inode, path);
4870 * We have logged all extents successfully, now make sure the commit of
4871 * the current transaction waits for the ordered extents to complete
4872 * before it commits and wipes out the log trees, otherwise we would
4873 * lose data if an ordered extents completes after the transaction
4874 * commits and a power failure happens after the transaction commit.
4876 list_for_each_entry_safe(ordered, tmp, &ctx->ordered_extents, log_list) {
4877 list_del_init(&ordered->log_list);
4878 set_bit(BTRFS_ORDERED_LOGGED, &ordered->flags);
4880 if (!test_bit(BTRFS_ORDERED_COMPLETE, &ordered->flags)) {
4881 spin_lock_irq(&inode->ordered_tree.lock);
4882 if (!test_bit(BTRFS_ORDERED_COMPLETE, &ordered->flags)) {
4883 set_bit(BTRFS_ORDERED_PENDING, &ordered->flags);
4884 atomic_inc(&trans->transaction->pending_ordered);
4886 spin_unlock_irq(&inode->ordered_tree.lock);
4888 btrfs_put_ordered_extent(ordered);
4894 static int logged_inode_size(struct btrfs_root *log, struct btrfs_inode *inode,
4895 struct btrfs_path *path, u64 *size_ret)
4897 struct btrfs_key key;
4900 key.objectid = btrfs_ino(inode);
4901 key.type = BTRFS_INODE_ITEM_KEY;
4904 ret = btrfs_search_slot(NULL, log, &key, path, 0, 0);
4907 } else if (ret > 0) {
4910 struct btrfs_inode_item *item;
4912 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
4913 struct btrfs_inode_item);
4914 *size_ret = btrfs_inode_size(path->nodes[0], item);
4916 * If the in-memory inode's i_size is smaller then the inode
4917 * size stored in the btree, return the inode's i_size, so
4918 * that we get a correct inode size after replaying the log
4919 * when before a power failure we had a shrinking truncate
4920 * followed by addition of a new name (rename / new hard link).
4921 * Otherwise return the inode size from the btree, to avoid
4922 * data loss when replaying a log due to previously doing a
4923 * write that expands the inode's size and logging a new name
4924 * immediately after.
4926 if (*size_ret > inode->vfs_inode.i_size)
4927 *size_ret = inode->vfs_inode.i_size;
4930 btrfs_release_path(path);
4935 * At the moment we always log all xattrs. This is to figure out at log replay
4936 * time which xattrs must have their deletion replayed. If a xattr is missing
4937 * in the log tree and exists in the fs/subvol tree, we delete it. This is
4938 * because if a xattr is deleted, the inode is fsynced and a power failure
4939 * happens, causing the log to be replayed the next time the fs is mounted,
4940 * we want the xattr to not exist anymore (same behaviour as other filesystems
4941 * with a journal, ext3/4, xfs, f2fs, etc).
4943 static int btrfs_log_all_xattrs(struct btrfs_trans_handle *trans,
4944 struct btrfs_inode *inode,
4945 struct btrfs_path *path,
4946 struct btrfs_path *dst_path)
4948 struct btrfs_root *root = inode->root;
4950 struct btrfs_key key;
4951 const u64 ino = btrfs_ino(inode);
4954 bool found_xattrs = false;
4956 if (test_bit(BTRFS_INODE_NO_XATTRS, &inode->runtime_flags))
4960 key.type = BTRFS_XATTR_ITEM_KEY;
4963 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4968 int slot = path->slots[0];
4969 struct extent_buffer *leaf = path->nodes[0];
4970 int nritems = btrfs_header_nritems(leaf);
4972 if (slot >= nritems) {
4974 ret = copy_items(trans, inode, dst_path, path,
4975 start_slot, ins_nr, 1, 0);
4980 ret = btrfs_next_leaf(root, path);
4988 btrfs_item_key_to_cpu(leaf, &key, slot);
4989 if (key.objectid != ino || key.type != BTRFS_XATTR_ITEM_KEY)
4996 found_xattrs = true;
5000 ret = copy_items(trans, inode, dst_path, path,
5001 start_slot, ins_nr, 1, 0);
5007 set_bit(BTRFS_INODE_NO_XATTRS, &inode->runtime_flags);
5013 * When using the NO_HOLES feature if we punched a hole that causes the
5014 * deletion of entire leafs or all the extent items of the first leaf (the one
5015 * that contains the inode item and references) we may end up not processing
5016 * any extents, because there are no leafs with a generation matching the
5017 * current transaction that have extent items for our inode. So we need to find
5018 * if any holes exist and then log them. We also need to log holes after any
5019 * truncate operation that changes the inode's size.
5021 static int btrfs_log_holes(struct btrfs_trans_handle *trans,
5022 struct btrfs_inode *inode,
5023 struct btrfs_path *path)
5025 struct btrfs_root *root = inode->root;
5026 struct btrfs_fs_info *fs_info = root->fs_info;
5027 struct btrfs_key key;
5028 const u64 ino = btrfs_ino(inode);
5029 const u64 i_size = i_size_read(&inode->vfs_inode);
5030 u64 prev_extent_end = 0;
5033 if (!btrfs_fs_incompat(fs_info, NO_HOLES) || i_size == 0)
5037 key.type = BTRFS_EXTENT_DATA_KEY;
5040 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5045 struct extent_buffer *leaf = path->nodes[0];
5047 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
5048 ret = btrfs_next_leaf(root, path);
5055 leaf = path->nodes[0];
5058 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
5059 if (key.objectid != ino || key.type != BTRFS_EXTENT_DATA_KEY)
5062 /* We have a hole, log it. */
5063 if (prev_extent_end < key.offset) {
5064 const u64 hole_len = key.offset - prev_extent_end;
5067 * Release the path to avoid deadlocks with other code
5068 * paths that search the root while holding locks on
5069 * leafs from the log root.
5071 btrfs_release_path(path);
5072 ret = btrfs_insert_file_extent(trans, root->log_root,
5073 ino, prev_extent_end, 0,
5074 0, hole_len, 0, hole_len,
5080 * Search for the same key again in the root. Since it's
5081 * an extent item and we are holding the inode lock, the
5082 * key must still exist. If it doesn't just emit warning
5083 * and return an error to fall back to a transaction
5086 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5089 if (WARN_ON(ret > 0))
5091 leaf = path->nodes[0];
5094 prev_extent_end = btrfs_file_extent_end(path);
5099 if (prev_extent_end < i_size) {
5102 btrfs_release_path(path);
5103 hole_len = ALIGN(i_size - prev_extent_end, fs_info->sectorsize);
5104 ret = btrfs_insert_file_extent(trans, root->log_root,
5105 ino, prev_extent_end, 0, 0,
5106 hole_len, 0, hole_len,
5116 * When we are logging a new inode X, check if it doesn't have a reference that
5117 * matches the reference from some other inode Y created in a past transaction
5118 * and that was renamed in the current transaction. If we don't do this, then at
5119 * log replay time we can lose inode Y (and all its files if it's a directory):
5122 * echo "hello world" > /mnt/x/foobar
5125 * mkdir /mnt/x # or touch /mnt/x
5126 * xfs_io -c fsync /mnt/x
5128 * mount fs, trigger log replay
5130 * After the log replay procedure, we would lose the first directory and all its
5131 * files (file foobar).
5132 * For the case where inode Y is not a directory we simply end up losing it:
5134 * echo "123" > /mnt/foo
5136 * mv /mnt/foo /mnt/bar
5137 * echo "abc" > /mnt/foo
5138 * xfs_io -c fsync /mnt/foo
5141 * We also need this for cases where a snapshot entry is replaced by some other
5142 * entry (file or directory) otherwise we end up with an unreplayable log due to
5143 * attempts to delete the snapshot entry (entry of type BTRFS_ROOT_ITEM_KEY) as
5144 * if it were a regular entry:
5147 * btrfs subvolume snapshot /mnt /mnt/x/snap
5148 * btrfs subvolume delete /mnt/x/snap
5151 * fsync /mnt/x or fsync some new file inside it
5154 * The snapshot delete, rmdir of x, mkdir of a new x and the fsync all happen in
5155 * the same transaction.
5157 static int btrfs_check_ref_name_override(struct extent_buffer *eb,
5159 const struct btrfs_key *key,
5160 struct btrfs_inode *inode,
5161 u64 *other_ino, u64 *other_parent)
5164 struct btrfs_path *search_path;
5167 u32 item_size = btrfs_item_size_nr(eb, slot);
5169 unsigned long ptr = btrfs_item_ptr_offset(eb, slot);
5171 search_path = btrfs_alloc_path();
5174 search_path->search_commit_root = 1;
5175 search_path->skip_locking = 1;
5177 while (cur_offset < item_size) {
5181 unsigned long name_ptr;
5182 struct btrfs_dir_item *di;
5184 if (key->type == BTRFS_INODE_REF_KEY) {
5185 struct btrfs_inode_ref *iref;
5187 iref = (struct btrfs_inode_ref *)(ptr + cur_offset);
5188 parent = key->offset;
5189 this_name_len = btrfs_inode_ref_name_len(eb, iref);
5190 name_ptr = (unsigned long)(iref + 1);
5191 this_len = sizeof(*iref) + this_name_len;
5193 struct btrfs_inode_extref *extref;
5195 extref = (struct btrfs_inode_extref *)(ptr +
5197 parent = btrfs_inode_extref_parent(eb, extref);
5198 this_name_len = btrfs_inode_extref_name_len(eb, extref);
5199 name_ptr = (unsigned long)&extref->name;
5200 this_len = sizeof(*extref) + this_name_len;
5203 if (this_name_len > name_len) {
5206 new_name = krealloc(name, this_name_len, GFP_NOFS);
5211 name_len = this_name_len;
5215 read_extent_buffer(eb, name, name_ptr, this_name_len);
5216 di = btrfs_lookup_dir_item(NULL, inode->root, search_path,
5217 parent, name, this_name_len, 0);
5218 if (di && !IS_ERR(di)) {
5219 struct btrfs_key di_key;
5221 btrfs_dir_item_key_to_cpu(search_path->nodes[0],
5223 if (di_key.type == BTRFS_INODE_ITEM_KEY) {
5224 if (di_key.objectid != key->objectid) {
5226 *other_ino = di_key.objectid;
5227 *other_parent = parent;
5235 } else if (IS_ERR(di)) {
5239 btrfs_release_path(search_path);
5241 cur_offset += this_len;
5245 btrfs_free_path(search_path);
5250 struct btrfs_ino_list {
5253 struct list_head list;
5256 static int log_conflicting_inodes(struct btrfs_trans_handle *trans,
5257 struct btrfs_root *root,
5258 struct btrfs_path *path,
5259 struct btrfs_log_ctx *ctx,
5260 u64 ino, u64 parent)
5262 struct btrfs_ino_list *ino_elem;
5263 LIST_HEAD(inode_list);
5266 ino_elem = kmalloc(sizeof(*ino_elem), GFP_NOFS);
5269 ino_elem->ino = ino;
5270 ino_elem->parent = parent;
5271 list_add_tail(&ino_elem->list, &inode_list);
5273 while (!list_empty(&inode_list)) {
5274 struct btrfs_fs_info *fs_info = root->fs_info;
5275 struct btrfs_key key;
5276 struct inode *inode;
5278 ino_elem = list_first_entry(&inode_list, struct btrfs_ino_list,
5280 ino = ino_elem->ino;
5281 parent = ino_elem->parent;
5282 list_del(&ino_elem->list);
5287 btrfs_release_path(path);
5289 inode = btrfs_iget(fs_info->sb, ino, root);
5291 * If the other inode that had a conflicting dir entry was
5292 * deleted in the current transaction, we need to log its parent
5295 if (IS_ERR(inode)) {
5296 ret = PTR_ERR(inode);
5297 if (ret == -ENOENT) {
5298 inode = btrfs_iget(fs_info->sb, parent, root);
5299 if (IS_ERR(inode)) {
5300 ret = PTR_ERR(inode);
5302 ret = btrfs_log_inode(trans,
5304 LOG_OTHER_INODE_ALL,
5306 btrfs_add_delayed_iput(inode);
5312 * If the inode was already logged skip it - otherwise we can
5313 * hit an infinite loop. Example:
5315 * From the commit root (previous transaction) we have the
5318 * inode 257 a directory
5319 * inode 258 with references "zz" and "zz_link" on inode 257
5320 * inode 259 with reference "a" on inode 257
5322 * And in the current (uncommitted) transaction we have:
5324 * inode 257 a directory, unchanged
5325 * inode 258 with references "a" and "a2" on inode 257
5326 * inode 259 with reference "zz_link" on inode 257
5327 * inode 261 with reference "zz" on inode 257
5329 * When logging inode 261 the following infinite loop could
5330 * happen if we don't skip already logged inodes:
5332 * - we detect inode 258 as a conflicting inode, with inode 261
5333 * on reference "zz", and log it;
5335 * - we detect inode 259 as a conflicting inode, with inode 258
5336 * on reference "a", and log it;
5338 * - we detect inode 258 as a conflicting inode, with inode 259
5339 * on reference "zz_link", and log it - again! After this we
5340 * repeat the above steps forever.
5342 spin_lock(&BTRFS_I(inode)->lock);
5344 * Check the inode's logged_trans only instead of
5345 * btrfs_inode_in_log(). This is because the last_log_commit of
5346 * the inode is not updated when we only log that it exists (see
5347 * btrfs_log_inode()).
5349 if (BTRFS_I(inode)->logged_trans == trans->transid) {
5350 spin_unlock(&BTRFS_I(inode)->lock);
5351 btrfs_add_delayed_iput(inode);
5354 spin_unlock(&BTRFS_I(inode)->lock);
5356 * We are safe logging the other inode without acquiring its
5357 * lock as long as we log with the LOG_INODE_EXISTS mode. We
5358 * are safe against concurrent renames of the other inode as
5359 * well because during a rename we pin the log and update the
5360 * log with the new name before we unpin it.
5362 ret = btrfs_log_inode(trans, BTRFS_I(inode), LOG_OTHER_INODE, ctx);
5364 btrfs_add_delayed_iput(inode);
5369 key.type = BTRFS_INODE_REF_KEY;
5371 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5373 btrfs_add_delayed_iput(inode);
5378 struct extent_buffer *leaf = path->nodes[0];
5379 int slot = path->slots[0];
5381 u64 other_parent = 0;
5383 if (slot >= btrfs_header_nritems(leaf)) {
5384 ret = btrfs_next_leaf(root, path);
5387 } else if (ret > 0) {
5394 btrfs_item_key_to_cpu(leaf, &key, slot);
5395 if (key.objectid != ino ||
5396 (key.type != BTRFS_INODE_REF_KEY &&
5397 key.type != BTRFS_INODE_EXTREF_KEY)) {
5402 ret = btrfs_check_ref_name_override(leaf, slot, &key,
5403 BTRFS_I(inode), &other_ino,
5408 ino_elem = kmalloc(sizeof(*ino_elem), GFP_NOFS);
5413 ino_elem->ino = other_ino;
5414 ino_elem->parent = other_parent;
5415 list_add_tail(&ino_elem->list, &inode_list);
5420 btrfs_add_delayed_iput(inode);
5426 static int copy_inode_items_to_log(struct btrfs_trans_handle *trans,
5427 struct btrfs_inode *inode,
5428 struct btrfs_key *min_key,
5429 const struct btrfs_key *max_key,
5430 struct btrfs_path *path,
5431 struct btrfs_path *dst_path,
5432 const u64 logged_isize,
5433 const bool recursive_logging,
5434 const int inode_only,
5435 struct btrfs_log_ctx *ctx,
5436 bool *need_log_inode_item)
5438 struct btrfs_root *root = inode->root;
5439 int ins_start_slot = 0;
5444 ret = btrfs_search_forward(root, min_key, path, trans->transid);
5452 /* Note, ins_nr might be > 0 here, cleanup outside the loop */
5453 if (min_key->objectid != max_key->objectid)
5455 if (min_key->type > max_key->type)
5458 if (min_key->type == BTRFS_INODE_ITEM_KEY)
5459 *need_log_inode_item = false;
5461 if ((min_key->type == BTRFS_INODE_REF_KEY ||
5462 min_key->type == BTRFS_INODE_EXTREF_KEY) &&
5463 inode->generation == trans->transid &&
5464 !recursive_logging) {
5466 u64 other_parent = 0;
5468 ret = btrfs_check_ref_name_override(path->nodes[0],
5469 path->slots[0], min_key, inode,
5470 &other_ino, &other_parent);
5473 } else if (ret > 0 &&
5474 other_ino != btrfs_ino(BTRFS_I(ctx->inode))) {
5479 ins_start_slot = path->slots[0];
5481 ret = copy_items(trans, inode, dst_path, path,
5482 ins_start_slot, ins_nr,
5483 inode_only, logged_isize);
5488 ret = log_conflicting_inodes(trans, root, path,
5489 ctx, other_ino, other_parent);
5492 btrfs_release_path(path);
5497 /* Skip xattrs, we log them later with btrfs_log_all_xattrs() */
5498 if (min_key->type == BTRFS_XATTR_ITEM_KEY) {
5501 ret = copy_items(trans, inode, dst_path, path,
5503 ins_nr, inode_only, logged_isize);
5510 if (ins_nr && ins_start_slot + ins_nr == path->slots[0]) {
5513 } else if (!ins_nr) {
5514 ins_start_slot = path->slots[0];
5519 ret = copy_items(trans, inode, dst_path, path, ins_start_slot,
5520 ins_nr, inode_only, logged_isize);
5524 ins_start_slot = path->slots[0];
5527 if (path->slots[0] < btrfs_header_nritems(path->nodes[0])) {
5528 btrfs_item_key_to_cpu(path->nodes[0], min_key,
5533 ret = copy_items(trans, inode, dst_path, path,
5534 ins_start_slot, ins_nr, inode_only,
5540 btrfs_release_path(path);
5542 if (min_key->offset < (u64)-1) {
5544 } else if (min_key->type < max_key->type) {
5546 min_key->offset = 0;
5552 ret = copy_items(trans, inode, dst_path, path, ins_start_slot,
5553 ins_nr, inode_only, logged_isize);
5558 /* log a single inode in the tree log.
5559 * At least one parent directory for this inode must exist in the tree
5560 * or be logged already.
5562 * Any items from this inode changed by the current transaction are copied
5563 * to the log tree. An extra reference is taken on any extents in this
5564 * file, allowing us to avoid a whole pile of corner cases around logging
5565 * blocks that have been removed from the tree.
5567 * See LOG_INODE_ALL and related defines for a description of what inode_only
5570 * This handles both files and directories.
5572 static int btrfs_log_inode(struct btrfs_trans_handle *trans,
5573 struct btrfs_inode *inode,
5575 struct btrfs_log_ctx *ctx)
5577 struct btrfs_path *path;
5578 struct btrfs_path *dst_path;
5579 struct btrfs_key min_key;
5580 struct btrfs_key max_key;
5581 struct btrfs_root *log = inode->root->log_root;
5584 bool fast_search = false;
5585 u64 ino = btrfs_ino(inode);
5586 struct extent_map_tree *em_tree = &inode->extent_tree;
5587 u64 logged_isize = 0;
5588 bool need_log_inode_item = true;
5589 bool xattrs_logged = false;
5590 bool recursive_logging = false;
5591 bool inode_item_dropped = true;
5593 path = btrfs_alloc_path();
5596 dst_path = btrfs_alloc_path();
5598 btrfs_free_path(path);
5602 min_key.objectid = ino;
5603 min_key.type = BTRFS_INODE_ITEM_KEY;
5606 max_key.objectid = ino;
5609 /* today the code can only do partial logging of directories */
5610 if (S_ISDIR(inode->vfs_inode.i_mode) ||
5611 (!test_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
5612 &inode->runtime_flags) &&
5613 inode_only >= LOG_INODE_EXISTS))
5614 max_key.type = BTRFS_XATTR_ITEM_KEY;
5616 max_key.type = (u8)-1;
5617 max_key.offset = (u64)-1;
5620 * Only run delayed items if we are a directory. We want to make sure
5621 * all directory indexes hit the fs/subvolume tree so we can find them
5622 * and figure out which index ranges have to be logged.
5624 if (S_ISDIR(inode->vfs_inode.i_mode)) {
5625 err = btrfs_commit_inode_delayed_items(trans, inode);
5630 if (inode_only == LOG_OTHER_INODE || inode_only == LOG_OTHER_INODE_ALL) {
5631 recursive_logging = true;
5632 if (inode_only == LOG_OTHER_INODE)
5633 inode_only = LOG_INODE_EXISTS;
5635 inode_only = LOG_INODE_ALL;
5636 mutex_lock_nested(&inode->log_mutex, SINGLE_DEPTH_NESTING);
5638 mutex_lock(&inode->log_mutex);
5642 * This is for cases where logging a directory could result in losing a
5643 * a file after replaying the log. For example, if we move a file from a
5644 * directory A to a directory B, then fsync directory A, we have no way
5645 * to known the file was moved from A to B, so logging just A would
5646 * result in losing the file after a log replay.
5648 if (S_ISDIR(inode->vfs_inode.i_mode) &&
5649 inode_only == LOG_INODE_ALL &&
5650 inode->last_unlink_trans >= trans->transid) {
5651 btrfs_set_log_full_commit(trans);
5657 * a brute force approach to making sure we get the most uptodate
5658 * copies of everything.
5660 if (S_ISDIR(inode->vfs_inode.i_mode)) {
5661 int max_key_type = BTRFS_DIR_LOG_INDEX_KEY;
5663 clear_bit(BTRFS_INODE_COPY_EVERYTHING, &inode->runtime_flags);
5664 if (inode_only == LOG_INODE_EXISTS)
5665 max_key_type = BTRFS_XATTR_ITEM_KEY;
5666 ret = drop_inode_items(trans, log, path, inode, max_key_type);
5668 if (inode_only == LOG_INODE_EXISTS && inode_logged(trans, inode)) {
5670 * Make sure the new inode item we write to the log has
5671 * the same isize as the current one (if it exists).
5672 * This is necessary to prevent data loss after log
5673 * replay, and also to prevent doing a wrong expanding
5674 * truncate - for e.g. create file, write 4K into offset
5675 * 0, fsync, write 4K into offset 4096, add hard link,
5676 * fsync some other file (to sync log), power fail - if
5677 * we use the inode's current i_size, after log replay
5678 * we get a 8Kb file, with the last 4Kb extent as a hole
5679 * (zeroes), as if an expanding truncate happened,
5680 * instead of getting a file of 4Kb only.
5682 err = logged_inode_size(log, inode, path, &logged_isize);
5686 if (test_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
5687 &inode->runtime_flags)) {
5688 if (inode_only == LOG_INODE_EXISTS) {
5689 max_key.type = BTRFS_XATTR_ITEM_KEY;
5690 ret = drop_inode_items(trans, log, path, inode,
5693 clear_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
5694 &inode->runtime_flags);
5695 clear_bit(BTRFS_INODE_COPY_EVERYTHING,
5696 &inode->runtime_flags);
5697 if (inode_logged(trans, inode))
5698 ret = truncate_inode_items(trans, log,
5701 } else if (test_and_clear_bit(BTRFS_INODE_COPY_EVERYTHING,
5702 &inode->runtime_flags) ||
5703 inode_only == LOG_INODE_EXISTS) {
5704 if (inode_only == LOG_INODE_ALL)
5706 max_key.type = BTRFS_XATTR_ITEM_KEY;
5707 ret = drop_inode_items(trans, log, path, inode,
5710 if (inode_only == LOG_INODE_ALL)
5712 inode_item_dropped = false;
5722 err = copy_inode_items_to_log(trans, inode, &min_key, &max_key,
5723 path, dst_path, logged_isize,
5724 recursive_logging, inode_only, ctx,
5725 &need_log_inode_item);
5729 btrfs_release_path(path);
5730 btrfs_release_path(dst_path);
5731 err = btrfs_log_all_xattrs(trans, inode, path, dst_path);
5734 xattrs_logged = true;
5735 if (max_key.type >= BTRFS_EXTENT_DATA_KEY && !fast_search) {
5736 btrfs_release_path(path);
5737 btrfs_release_path(dst_path);
5738 err = btrfs_log_holes(trans, inode, path);
5743 btrfs_release_path(path);
5744 btrfs_release_path(dst_path);
5745 if (need_log_inode_item) {
5746 err = log_inode_item(trans, log, dst_path, inode, inode_item_dropped);
5750 * If we are doing a fast fsync and the inode was logged before
5751 * in this transaction, we don't need to log the xattrs because
5752 * they were logged before. If xattrs were added, changed or
5753 * deleted since the last time we logged the inode, then we have
5754 * already logged them because the inode had the runtime flag
5755 * BTRFS_INODE_COPY_EVERYTHING set.
5757 if (!xattrs_logged && inode->logged_trans < trans->transid) {
5758 err = btrfs_log_all_xattrs(trans, inode, path, dst_path);
5761 btrfs_release_path(path);
5765 ret = btrfs_log_changed_extents(trans, inode, dst_path, ctx);
5770 } else if (inode_only == LOG_INODE_ALL) {
5771 struct extent_map *em, *n;
5773 write_lock(&em_tree->lock);
5774 list_for_each_entry_safe(em, n, &em_tree->modified_extents, list)
5775 list_del_init(&em->list);
5776 write_unlock(&em_tree->lock);
5779 if (inode_only == LOG_INODE_ALL && S_ISDIR(inode->vfs_inode.i_mode)) {
5780 ret = log_directory_changes(trans, inode, path, dst_path, ctx);
5787 spin_lock(&inode->lock);
5788 inode->logged_trans = trans->transid;
5790 * Don't update last_log_commit if we logged that an inode exists.
5791 * We do this for three reasons:
5793 * 1) We might have had buffered writes to this inode that were
5794 * flushed and had their ordered extents completed in this
5795 * transaction, but we did not previously log the inode with
5796 * LOG_INODE_ALL. Later the inode was evicted and after that
5797 * it was loaded again and this LOG_INODE_EXISTS log operation
5798 * happened. We must make sure that if an explicit fsync against
5799 * the inode is performed later, it logs the new extents, an
5800 * updated inode item, etc, and syncs the log. The same logic
5801 * applies to direct IO writes instead of buffered writes.
5803 * 2) When we log the inode with LOG_INODE_EXISTS, its inode item
5804 * is logged with an i_size of 0 or whatever value was logged
5805 * before. If later the i_size of the inode is increased by a
5806 * truncate operation, the log is synced through an fsync of
5807 * some other inode and then finally an explicit fsync against
5808 * this inode is made, we must make sure this fsync logs the
5809 * inode with the new i_size, the hole between old i_size and
5810 * the new i_size, and syncs the log.
5812 * 3) If we are logging that an ancestor inode exists as part of
5813 * logging a new name from a link or rename operation, don't update
5814 * its last_log_commit - otherwise if an explicit fsync is made
5815 * against an ancestor, the fsync considers the inode in the log
5816 * and doesn't sync the log, resulting in the ancestor missing after
5817 * a power failure unless the log was synced as part of an fsync
5818 * against any other unrelated inode.
5820 if (inode_only != LOG_INODE_EXISTS)
5821 inode->last_log_commit = inode->last_sub_trans;
5822 spin_unlock(&inode->lock);
5824 mutex_unlock(&inode->log_mutex);
5826 btrfs_free_path(path);
5827 btrfs_free_path(dst_path);
5832 * Check if we need to log an inode. This is used in contexts where while
5833 * logging an inode we need to log another inode (either that it exists or in
5834 * full mode). This is used instead of btrfs_inode_in_log() because the later
5835 * requires the inode to be in the log and have the log transaction committed,
5836 * while here we do not care if the log transaction was already committed - our
5837 * caller will commit the log later - and we want to avoid logging an inode
5838 * multiple times when multiple tasks have joined the same log transaction.
5840 static bool need_log_inode(struct btrfs_trans_handle *trans,
5841 struct btrfs_inode *inode)
5844 * If a directory was not modified, no dentries added or removed, we can
5845 * and should avoid logging it.
5847 if (S_ISDIR(inode->vfs_inode.i_mode) && inode->last_trans < trans->transid)
5851 * If this inode does not have new/updated/deleted xattrs since the last
5852 * time it was logged and is flagged as logged in the current transaction,
5853 * we can skip logging it. As for new/deleted names, those are updated in
5854 * the log by link/unlink/rename operations.
5855 * In case the inode was logged and then evicted and reloaded, its
5856 * logged_trans will be 0, in which case we have to fully log it since
5857 * logged_trans is a transient field, not persisted.
5859 if (inode->logged_trans == trans->transid &&
5860 !test_bit(BTRFS_INODE_COPY_EVERYTHING, &inode->runtime_flags))
5866 struct btrfs_dir_list {
5868 struct list_head list;
5872 * Log the inodes of the new dentries of a directory. See log_dir_items() for
5873 * details about the why it is needed.
5874 * This is a recursive operation - if an existing dentry corresponds to a
5875 * directory, that directory's new entries are logged too (same behaviour as
5876 * ext3/4, xfs, f2fs, reiserfs, nilfs2). Note that when logging the inodes
5877 * the dentries point to we do not lock their i_mutex, otherwise lockdep
5878 * complains about the following circular lock dependency / possible deadlock:
5882 * lock(&type->i_mutex_dir_key#3/2);
5883 * lock(sb_internal#2);
5884 * lock(&type->i_mutex_dir_key#3/2);
5885 * lock(&sb->s_type->i_mutex_key#14);
5887 * Where sb_internal is the lock (a counter that works as a lock) acquired by
5888 * sb_start_intwrite() in btrfs_start_transaction().
5889 * Not locking i_mutex of the inodes is still safe because:
5891 * 1) For regular files we log with a mode of LOG_INODE_EXISTS. It's possible
5892 * that while logging the inode new references (names) are added or removed
5893 * from the inode, leaving the logged inode item with a link count that does
5894 * not match the number of logged inode reference items. This is fine because
5895 * at log replay time we compute the real number of links and correct the
5896 * link count in the inode item (see replay_one_buffer() and
5897 * link_to_fixup_dir());
5899 * 2) For directories we log with a mode of LOG_INODE_ALL. It's possible that
5900 * while logging the inode's items new items with keys BTRFS_DIR_ITEM_KEY and
5901 * BTRFS_DIR_INDEX_KEY are added to fs/subvol tree and the logged inode item
5902 * has a size that doesn't match the sum of the lengths of all the logged
5903 * names. This does not result in a problem because if a dir_item key is
5904 * logged but its matching dir_index key is not logged, at log replay time we
5905 * don't use it to replay the respective name (see replay_one_name()). On the
5906 * other hand if only the dir_index key ends up being logged, the respective
5907 * name is added to the fs/subvol tree with both the dir_item and dir_index
5908 * keys created (see replay_one_name()).
5909 * The directory's inode item with a wrong i_size is not a problem as well,
5910 * since we don't use it at log replay time to set the i_size in the inode
5911 * item of the fs/subvol tree (see overwrite_item()).
5913 static int log_new_dir_dentries(struct btrfs_trans_handle *trans,
5914 struct btrfs_root *root,
5915 struct btrfs_inode *start_inode,
5916 struct btrfs_log_ctx *ctx)
5918 struct btrfs_fs_info *fs_info = root->fs_info;
5919 struct btrfs_root *log = root->log_root;
5920 struct btrfs_path *path;
5921 LIST_HEAD(dir_list);
5922 struct btrfs_dir_list *dir_elem;
5926 * If we are logging a new name, as part of a link or rename operation,
5927 * don't bother logging new dentries, as we just want to log the names
5928 * of an inode and that any new parents exist.
5930 if (ctx->logging_new_name)
5933 path = btrfs_alloc_path();
5937 dir_elem = kmalloc(sizeof(*dir_elem), GFP_NOFS);
5939 btrfs_free_path(path);
5942 dir_elem->ino = btrfs_ino(start_inode);
5943 list_add_tail(&dir_elem->list, &dir_list);
5945 while (!list_empty(&dir_list)) {
5946 struct extent_buffer *leaf;
5947 struct btrfs_key min_key;
5951 dir_elem = list_first_entry(&dir_list, struct btrfs_dir_list,
5954 goto next_dir_inode;
5956 min_key.objectid = dir_elem->ino;
5957 min_key.type = BTRFS_DIR_ITEM_KEY;
5960 btrfs_release_path(path);
5961 ret = btrfs_search_forward(log, &min_key, path, trans->transid);
5963 goto next_dir_inode;
5964 } else if (ret > 0) {
5966 goto next_dir_inode;
5970 leaf = path->nodes[0];
5971 nritems = btrfs_header_nritems(leaf);
5972 for (i = path->slots[0]; i < nritems; i++) {
5973 struct btrfs_dir_item *di;
5974 struct btrfs_key di_key;
5975 struct inode *di_inode;
5976 struct btrfs_dir_list *new_dir_elem;
5977 int log_mode = LOG_INODE_EXISTS;
5980 btrfs_item_key_to_cpu(leaf, &min_key, i);
5981 if (min_key.objectid != dir_elem->ino ||
5982 min_key.type != BTRFS_DIR_ITEM_KEY)
5983 goto next_dir_inode;
5985 di = btrfs_item_ptr(leaf, i, struct btrfs_dir_item);
5986 type = btrfs_dir_type(leaf, di);
5987 if (btrfs_dir_transid(leaf, di) < trans->transid &&
5988 type != BTRFS_FT_DIR)
5990 btrfs_dir_item_key_to_cpu(leaf, di, &di_key);
5991 if (di_key.type == BTRFS_ROOT_ITEM_KEY)
5994 btrfs_release_path(path);
5995 di_inode = btrfs_iget(fs_info->sb, di_key.objectid, root);
5996 if (IS_ERR(di_inode)) {
5997 ret = PTR_ERR(di_inode);
5998 goto next_dir_inode;
6001 if (!need_log_inode(trans, BTRFS_I(di_inode))) {
6002 btrfs_add_delayed_iput(di_inode);
6006 ctx->log_new_dentries = false;
6007 if (type == BTRFS_FT_DIR || type == BTRFS_FT_SYMLINK)
6008 log_mode = LOG_INODE_ALL;
6009 ret = btrfs_log_inode(trans, BTRFS_I(di_inode),
6011 btrfs_add_delayed_iput(di_inode);
6013 goto next_dir_inode;
6014 if (ctx->log_new_dentries) {
6015 new_dir_elem = kmalloc(sizeof(*new_dir_elem),
6017 if (!new_dir_elem) {
6019 goto next_dir_inode;
6021 new_dir_elem->ino = di_key.objectid;
6022 list_add_tail(&new_dir_elem->list, &dir_list);
6027 ret = btrfs_next_leaf(log, path);
6029 goto next_dir_inode;
6030 } else if (ret > 0) {
6032 goto next_dir_inode;
6036 if (min_key.offset < (u64)-1) {
6041 list_del(&dir_elem->list);
6045 btrfs_free_path(path);
6049 static int btrfs_log_all_parents(struct btrfs_trans_handle *trans,
6050 struct btrfs_inode *inode,
6051 struct btrfs_log_ctx *ctx)
6053 struct btrfs_fs_info *fs_info = trans->fs_info;
6055 struct btrfs_path *path;
6056 struct btrfs_key key;
6057 struct btrfs_root *root = inode->root;
6058 const u64 ino = btrfs_ino(inode);
6060 path = btrfs_alloc_path();
6063 path->skip_locking = 1;
6064 path->search_commit_root = 1;
6067 key.type = BTRFS_INODE_REF_KEY;
6069 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6074 struct extent_buffer *leaf = path->nodes[0];
6075 int slot = path->slots[0];
6080 if (slot >= btrfs_header_nritems(leaf)) {
6081 ret = btrfs_next_leaf(root, path);
6089 btrfs_item_key_to_cpu(leaf, &key, slot);
6090 /* BTRFS_INODE_EXTREF_KEY is BTRFS_INODE_REF_KEY + 1 */
6091 if (key.objectid != ino || key.type > BTRFS_INODE_EXTREF_KEY)
6094 item_size = btrfs_item_size_nr(leaf, slot);
6095 ptr = btrfs_item_ptr_offset(leaf, slot);
6096 while (cur_offset < item_size) {
6097 struct btrfs_key inode_key;
6098 struct inode *dir_inode;
6100 inode_key.type = BTRFS_INODE_ITEM_KEY;
6101 inode_key.offset = 0;
6103 if (key.type == BTRFS_INODE_EXTREF_KEY) {
6104 struct btrfs_inode_extref *extref;
6106 extref = (struct btrfs_inode_extref *)
6108 inode_key.objectid = btrfs_inode_extref_parent(
6110 cur_offset += sizeof(*extref);
6111 cur_offset += btrfs_inode_extref_name_len(leaf,
6114 inode_key.objectid = key.offset;
6115 cur_offset = item_size;
6118 dir_inode = btrfs_iget(fs_info->sb, inode_key.objectid,
6121 * If the parent inode was deleted, return an error to
6122 * fallback to a transaction commit. This is to prevent
6123 * getting an inode that was moved from one parent A to
6124 * a parent B, got its former parent A deleted and then
6125 * it got fsync'ed, from existing at both parents after
6126 * a log replay (and the old parent still existing).
6133 * mv /mnt/B/bar /mnt/A/bar
6134 * mv -T /mnt/A /mnt/B
6138 * If we ignore the old parent B which got deleted,
6139 * after a log replay we would have file bar linked
6140 * at both parents and the old parent B would still
6143 if (IS_ERR(dir_inode)) {
6144 ret = PTR_ERR(dir_inode);
6148 if (!need_log_inode(trans, BTRFS_I(dir_inode))) {
6149 btrfs_add_delayed_iput(dir_inode);
6153 ctx->log_new_dentries = false;
6154 ret = btrfs_log_inode(trans, BTRFS_I(dir_inode),
6155 LOG_INODE_ALL, ctx);
6156 if (!ret && ctx->log_new_dentries)
6157 ret = log_new_dir_dentries(trans, root,
6158 BTRFS_I(dir_inode), ctx);
6159 btrfs_add_delayed_iput(dir_inode);
6167 btrfs_free_path(path);
6171 static int log_new_ancestors(struct btrfs_trans_handle *trans,
6172 struct btrfs_root *root,
6173 struct btrfs_path *path,
6174 struct btrfs_log_ctx *ctx)
6176 struct btrfs_key found_key;
6178 btrfs_item_key_to_cpu(path->nodes[0], &found_key, path->slots[0]);
6181 struct btrfs_fs_info *fs_info = root->fs_info;
6182 struct extent_buffer *leaf = path->nodes[0];
6183 int slot = path->slots[0];
6184 struct btrfs_key search_key;
6185 struct inode *inode;
6189 btrfs_release_path(path);
6191 ino = found_key.offset;
6193 search_key.objectid = found_key.offset;
6194 search_key.type = BTRFS_INODE_ITEM_KEY;
6195 search_key.offset = 0;
6196 inode = btrfs_iget(fs_info->sb, ino, root);
6198 return PTR_ERR(inode);
6200 if (BTRFS_I(inode)->generation >= trans->transid &&
6201 need_log_inode(trans, BTRFS_I(inode)))
6202 ret = btrfs_log_inode(trans, BTRFS_I(inode),
6203 LOG_INODE_EXISTS, ctx);
6204 btrfs_add_delayed_iput(inode);
6208 if (search_key.objectid == BTRFS_FIRST_FREE_OBJECTID)
6211 search_key.type = BTRFS_INODE_REF_KEY;
6212 ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
6216 leaf = path->nodes[0];
6217 slot = path->slots[0];
6218 if (slot >= btrfs_header_nritems(leaf)) {
6219 ret = btrfs_next_leaf(root, path);
6224 leaf = path->nodes[0];
6225 slot = path->slots[0];
6228 btrfs_item_key_to_cpu(leaf, &found_key, slot);
6229 if (found_key.objectid != search_key.objectid ||
6230 found_key.type != BTRFS_INODE_REF_KEY)
6236 static int log_new_ancestors_fast(struct btrfs_trans_handle *trans,
6237 struct btrfs_inode *inode,
6238 struct dentry *parent,
6239 struct btrfs_log_ctx *ctx)
6241 struct btrfs_root *root = inode->root;
6242 struct dentry *old_parent = NULL;
6243 struct super_block *sb = inode->vfs_inode.i_sb;
6247 if (!parent || d_really_is_negative(parent) ||
6251 inode = BTRFS_I(d_inode(parent));
6252 if (root != inode->root)
6255 if (inode->generation >= trans->transid &&
6256 need_log_inode(trans, inode)) {
6257 ret = btrfs_log_inode(trans, inode,
6258 LOG_INODE_EXISTS, ctx);
6262 if (IS_ROOT(parent))
6265 parent = dget_parent(parent);
6267 old_parent = parent;
6274 static int log_all_new_ancestors(struct btrfs_trans_handle *trans,
6275 struct btrfs_inode *inode,
6276 struct dentry *parent,
6277 struct btrfs_log_ctx *ctx)
6279 struct btrfs_root *root = inode->root;
6280 const u64 ino = btrfs_ino(inode);
6281 struct btrfs_path *path;
6282 struct btrfs_key search_key;
6286 * For a single hard link case, go through a fast path that does not
6287 * need to iterate the fs/subvolume tree.
6289 if (inode->vfs_inode.i_nlink < 2)
6290 return log_new_ancestors_fast(trans, inode, parent, ctx);
6292 path = btrfs_alloc_path();
6296 search_key.objectid = ino;
6297 search_key.type = BTRFS_INODE_REF_KEY;
6298 search_key.offset = 0;
6300 ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
6307 struct extent_buffer *leaf = path->nodes[0];
6308 int slot = path->slots[0];
6309 struct btrfs_key found_key;
6311 if (slot >= btrfs_header_nritems(leaf)) {
6312 ret = btrfs_next_leaf(root, path);
6320 btrfs_item_key_to_cpu(leaf, &found_key, slot);
6321 if (found_key.objectid != ino ||
6322 found_key.type > BTRFS_INODE_EXTREF_KEY)
6326 * Don't deal with extended references because they are rare
6327 * cases and too complex to deal with (we would need to keep
6328 * track of which subitem we are processing for each item in
6329 * this loop, etc). So just return some error to fallback to
6330 * a transaction commit.
6332 if (found_key.type == BTRFS_INODE_EXTREF_KEY) {
6338 * Logging ancestors needs to do more searches on the fs/subvol
6339 * tree, so it releases the path as needed to avoid deadlocks.
6340 * Keep track of the last inode ref key and resume from that key
6341 * after logging all new ancestors for the current hard link.
6343 memcpy(&search_key, &found_key, sizeof(search_key));
6345 ret = log_new_ancestors(trans, root, path, ctx);
6348 btrfs_release_path(path);
6353 btrfs_free_path(path);
6358 * helper function around btrfs_log_inode to make sure newly created
6359 * parent directories also end up in the log. A minimal inode and backref
6360 * only logging is done of any parent directories that are older than
6361 * the last committed transaction
6363 static int btrfs_log_inode_parent(struct btrfs_trans_handle *trans,
6364 struct btrfs_inode *inode,
6365 struct dentry *parent,
6367 struct btrfs_log_ctx *ctx)
6369 struct btrfs_root *root = inode->root;
6370 struct btrfs_fs_info *fs_info = root->fs_info;
6372 bool log_dentries = false;
6374 if (btrfs_test_opt(fs_info, NOTREELOG)) {
6379 if (btrfs_root_refs(&root->root_item) == 0) {
6385 * Skip already logged inodes or inodes corresponding to tmpfiles
6386 * (since logging them is pointless, a link count of 0 means they
6387 * will never be accessible).
6389 if ((btrfs_inode_in_log(inode, trans->transid) &&
6390 list_empty(&ctx->ordered_extents)) ||
6391 inode->vfs_inode.i_nlink == 0) {
6392 ret = BTRFS_NO_LOG_SYNC;
6396 ret = start_log_trans(trans, root, ctx);
6400 ret = btrfs_log_inode(trans, inode, inode_only, ctx);
6405 * for regular files, if its inode is already on disk, we don't
6406 * have to worry about the parents at all. This is because
6407 * we can use the last_unlink_trans field to record renames
6408 * and other fun in this file.
6410 if (S_ISREG(inode->vfs_inode.i_mode) &&
6411 inode->generation < trans->transid &&
6412 inode->last_unlink_trans < trans->transid) {
6417 if (S_ISDIR(inode->vfs_inode.i_mode) && ctx->log_new_dentries)
6418 log_dentries = true;
6421 * On unlink we must make sure all our current and old parent directory
6422 * inodes are fully logged. This is to prevent leaving dangling
6423 * directory index entries in directories that were our parents but are
6424 * not anymore. Not doing this results in old parent directory being
6425 * impossible to delete after log replay (rmdir will always fail with
6426 * error -ENOTEMPTY).
6432 * ln testdir/foo testdir/bar
6434 * unlink testdir/bar
6435 * xfs_io -c fsync testdir/foo
6437 * mount fs, triggers log replay
6439 * If we don't log the parent directory (testdir), after log replay the
6440 * directory still has an entry pointing to the file inode using the bar
6441 * name, but a matching BTRFS_INODE_[REF|EXTREF]_KEY does not exist and
6442 * the file inode has a link count of 1.
6448 * ln foo testdir/foo2
6449 * ln foo testdir/foo3
6451 * unlink testdir/foo3
6452 * xfs_io -c fsync foo
6454 * mount fs, triggers log replay
6456 * Similar as the first example, after log replay the parent directory
6457 * testdir still has an entry pointing to the inode file with name foo3
6458 * but the file inode does not have a matching BTRFS_INODE_REF_KEY item
6459 * and has a link count of 2.
6461 if (inode->last_unlink_trans >= trans->transid) {
6462 ret = btrfs_log_all_parents(trans, inode, ctx);
6467 ret = log_all_new_ancestors(trans, inode, parent, ctx);
6472 ret = log_new_dir_dentries(trans, root, inode, ctx);
6477 btrfs_set_log_full_commit(trans);
6482 btrfs_remove_log_ctx(root, ctx);
6483 btrfs_end_log_trans(root);
6489 * it is not safe to log dentry if the chunk root has added new
6490 * chunks. This returns 0 if the dentry was logged, and 1 otherwise.
6491 * If this returns 1, you must commit the transaction to safely get your
6494 int btrfs_log_dentry_safe(struct btrfs_trans_handle *trans,
6495 struct dentry *dentry,
6496 struct btrfs_log_ctx *ctx)
6498 struct dentry *parent = dget_parent(dentry);
6501 ret = btrfs_log_inode_parent(trans, BTRFS_I(d_inode(dentry)), parent,
6502 LOG_INODE_ALL, ctx);
6509 * should be called during mount to recover any replay any log trees
6512 int btrfs_recover_log_trees(struct btrfs_root *log_root_tree)
6515 struct btrfs_path *path;
6516 struct btrfs_trans_handle *trans;
6517 struct btrfs_key key;
6518 struct btrfs_key found_key;
6519 struct btrfs_root *log;
6520 struct btrfs_fs_info *fs_info = log_root_tree->fs_info;
6521 struct walk_control wc = {
6522 .process_func = process_one_buffer,
6523 .stage = LOG_WALK_PIN_ONLY,
6526 path = btrfs_alloc_path();
6530 set_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags);
6532 trans = btrfs_start_transaction(fs_info->tree_root, 0);
6533 if (IS_ERR(trans)) {
6534 ret = PTR_ERR(trans);
6541 ret = walk_log_tree(trans, log_root_tree, &wc);
6543 btrfs_abort_transaction(trans, ret);
6548 key.objectid = BTRFS_TREE_LOG_OBJECTID;
6549 key.offset = (u64)-1;
6550 key.type = BTRFS_ROOT_ITEM_KEY;
6553 ret = btrfs_search_slot(NULL, log_root_tree, &key, path, 0, 0);
6556 btrfs_abort_transaction(trans, ret);
6560 if (path->slots[0] == 0)
6564 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
6566 btrfs_release_path(path);
6567 if (found_key.objectid != BTRFS_TREE_LOG_OBJECTID)
6570 log = btrfs_read_tree_root(log_root_tree, &found_key);
6573 btrfs_abort_transaction(trans, ret);
6577 wc.replay_dest = btrfs_get_fs_root(fs_info, found_key.offset,
6579 if (IS_ERR(wc.replay_dest)) {
6580 ret = PTR_ERR(wc.replay_dest);
6583 * We didn't find the subvol, likely because it was
6584 * deleted. This is ok, simply skip this log and go to
6587 * We need to exclude the root because we can't have
6588 * other log replays overwriting this log as we'll read
6589 * it back in a few more times. This will keep our
6590 * block from being modified, and we'll just bail for
6591 * each subsequent pass.
6594 ret = btrfs_pin_extent_for_log_replay(trans,
6597 btrfs_put_root(log);
6601 btrfs_abort_transaction(trans, ret);
6605 wc.replay_dest->log_root = log;
6606 ret = btrfs_record_root_in_trans(trans, wc.replay_dest);
6608 /* The loop needs to continue due to the root refs */
6609 btrfs_abort_transaction(trans, ret);
6611 ret = walk_log_tree(trans, log, &wc);
6613 if (!ret && wc.stage == LOG_WALK_REPLAY_ALL) {
6614 ret = fixup_inode_link_counts(trans, wc.replay_dest,
6617 btrfs_abort_transaction(trans, ret);
6620 if (!ret && wc.stage == LOG_WALK_REPLAY_ALL) {
6621 struct btrfs_root *root = wc.replay_dest;
6623 btrfs_release_path(path);
6626 * We have just replayed everything, and the highest
6627 * objectid of fs roots probably has changed in case
6628 * some inode_item's got replayed.
6630 * root->objectid_mutex is not acquired as log replay
6631 * could only happen during mount.
6633 ret = btrfs_init_root_free_objectid(root);
6635 btrfs_abort_transaction(trans, ret);
6638 wc.replay_dest->log_root = NULL;
6639 btrfs_put_root(wc.replay_dest);
6640 btrfs_put_root(log);
6645 if (found_key.offset == 0)
6647 key.offset = found_key.offset - 1;
6649 btrfs_release_path(path);
6651 /* step one is to pin it all, step two is to replay just inodes */
6654 wc.process_func = replay_one_buffer;
6655 wc.stage = LOG_WALK_REPLAY_INODES;
6658 /* step three is to replay everything */
6659 if (wc.stage < LOG_WALK_REPLAY_ALL) {
6664 btrfs_free_path(path);
6666 /* step 4: commit the transaction, which also unpins the blocks */
6667 ret = btrfs_commit_transaction(trans);
6671 log_root_tree->log_root = NULL;
6672 clear_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags);
6673 btrfs_put_root(log_root_tree);
6678 btrfs_end_transaction(wc.trans);
6679 clear_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags);
6680 btrfs_free_path(path);
6685 * there are some corner cases where we want to force a full
6686 * commit instead of allowing a directory to be logged.
6688 * They revolve around files there were unlinked from the directory, and
6689 * this function updates the parent directory so that a full commit is
6690 * properly done if it is fsync'd later after the unlinks are done.
6692 * Must be called before the unlink operations (updates to the subvolume tree,
6693 * inodes, etc) are done.
6695 void btrfs_record_unlink_dir(struct btrfs_trans_handle *trans,
6696 struct btrfs_inode *dir, struct btrfs_inode *inode,
6700 * when we're logging a file, if it hasn't been renamed
6701 * or unlinked, and its inode is fully committed on disk,
6702 * we don't have to worry about walking up the directory chain
6703 * to log its parents.
6705 * So, we use the last_unlink_trans field to put this transid
6706 * into the file. When the file is logged we check it and
6707 * don't log the parents if the file is fully on disk.
6709 mutex_lock(&inode->log_mutex);
6710 inode->last_unlink_trans = trans->transid;
6711 mutex_unlock(&inode->log_mutex);
6714 * if this directory was already logged any new
6715 * names for this file/dir will get recorded
6717 if (dir->logged_trans == trans->transid)
6721 * if the inode we're about to unlink was logged,
6722 * the log will be properly updated for any new names
6724 if (inode->logged_trans == trans->transid)
6728 * when renaming files across directories, if the directory
6729 * there we're unlinking from gets fsync'd later on, there's
6730 * no way to find the destination directory later and fsync it
6731 * properly. So, we have to be conservative and force commits
6732 * so the new name gets discovered.
6737 /* we can safely do the unlink without any special recording */
6741 mutex_lock(&dir->log_mutex);
6742 dir->last_unlink_trans = trans->transid;
6743 mutex_unlock(&dir->log_mutex);
6747 * Make sure that if someone attempts to fsync the parent directory of a deleted
6748 * snapshot, it ends up triggering a transaction commit. This is to guarantee
6749 * that after replaying the log tree of the parent directory's root we will not
6750 * see the snapshot anymore and at log replay time we will not see any log tree
6751 * corresponding to the deleted snapshot's root, which could lead to replaying
6752 * it after replaying the log tree of the parent directory (which would replay
6753 * the snapshot delete operation).
6755 * Must be called before the actual snapshot destroy operation (updates to the
6756 * parent root and tree of tree roots trees, etc) are done.
6758 void btrfs_record_snapshot_destroy(struct btrfs_trans_handle *trans,
6759 struct btrfs_inode *dir)
6761 mutex_lock(&dir->log_mutex);
6762 dir->last_unlink_trans = trans->transid;
6763 mutex_unlock(&dir->log_mutex);
6767 * Call this after adding a new name for a file and it will properly
6768 * update the log to reflect the new name.
6770 void btrfs_log_new_name(struct btrfs_trans_handle *trans,
6771 struct btrfs_inode *inode, struct btrfs_inode *old_dir,
6772 struct dentry *parent)
6774 struct btrfs_log_ctx ctx;
6777 * this will force the logging code to walk the dentry chain
6780 if (!S_ISDIR(inode->vfs_inode.i_mode))
6781 inode->last_unlink_trans = trans->transid;
6784 * if this inode hasn't been logged and directory we're renaming it
6785 * from hasn't been logged, we don't need to log it
6787 if (!inode_logged(trans, inode) &&
6788 (!old_dir || !inode_logged(trans, old_dir)))
6792 * If we are doing a rename (old_dir is not NULL) from a directory that
6793 * was previously logged, make sure the next log attempt on the directory
6794 * is not skipped and logs the inode again. This is because the log may
6795 * not currently be authoritative for a range including the old
6796 * BTRFS_DIR_ITEM_KEY and BTRFS_DIR_INDEX_KEY keys, so we want to make
6797 * sure after a log replay we do not end up with both the new and old
6798 * dentries around (in case the inode is a directory we would have a
6799 * directory with two hard links and 2 inode references for different
6800 * parents). The next log attempt of old_dir will happen at
6801 * btrfs_log_all_parents(), called through btrfs_log_inode_parent()
6802 * below, because we have previously set inode->last_unlink_trans to the
6803 * current transaction ID, either here or at btrfs_record_unlink_dir() in
6804 * case inode is a directory.
6807 old_dir->logged_trans = 0;
6809 btrfs_init_log_ctx(&ctx, &inode->vfs_inode);
6810 ctx.logging_new_name = true;
6812 * We don't care about the return value. If we fail to log the new name
6813 * then we know the next attempt to sync the log will fallback to a full
6814 * transaction commit (due to a call to btrfs_set_log_full_commit()), so
6815 * we don't need to worry about getting a log committed that has an
6816 * inconsistent state after a rename operation.
6818 btrfs_log_inode_parent(trans, inode, parent, LOG_INODE_EXISTS, &ctx);