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"
23 #include "inode-item.h"
25 /* magic values for the inode_only field in btrfs_log_inode:
27 * LOG_INODE_ALL means to log everything
28 * LOG_INODE_EXISTS means to log just enough to recreate the inode
39 * directory trouble cases
41 * 1) on rename or unlink, if the inode being unlinked isn't in the fsync
42 * log, we must force a full commit before doing an fsync of the directory
43 * where the unlink was done.
44 * ---> record transid of last unlink/rename per directory
48 * rename foo/some_dir foo2/some_dir
50 * fsync foo/some_dir/some_file
52 * The fsync above will unlink the original some_dir without recording
53 * it in its new location (foo2). After a crash, some_dir will be gone
54 * unless the fsync of some_file forces a full commit
56 * 2) we must log any new names for any file or dir that is in the fsync
57 * log. ---> check inode while renaming/linking.
59 * 2a) we must log any new names for any file or dir during rename
60 * when the directory they are being removed from was logged.
61 * ---> check inode and old parent dir during rename
63 * 2a is actually the more important variant. With the extra logging
64 * a crash might unlink the old name without recreating the new one
66 * 3) after a crash, we must go through any directories with a link count
67 * of zero and redo the rm -rf
74 * The directory f1 was fully removed from the FS, but fsync was never
75 * called on f1, only its parent dir. After a crash the rm -rf must
76 * be replayed. This must be able to recurse down the entire
77 * directory tree. The inode link count fixup code takes care of the
82 * stages for the tree walking. The first
83 * stage (0) is to only pin down the blocks we find
84 * the second stage (1) is to make sure that all the inodes
85 * we find in the log are created in the subvolume.
87 * The last stage is to deal with directories and links and extents
88 * and all the other fun semantics
92 LOG_WALK_REPLAY_INODES
,
93 LOG_WALK_REPLAY_DIR_INDEX
,
97 static int btrfs_log_inode(struct btrfs_trans_handle
*trans
,
98 struct btrfs_inode
*inode
,
100 struct btrfs_log_ctx
*ctx
);
101 static int link_to_fixup_dir(struct btrfs_trans_handle
*trans
,
102 struct btrfs_root
*root
,
103 struct btrfs_path
*path
, u64 objectid
);
104 static noinline
int replay_dir_deletes(struct btrfs_trans_handle
*trans
,
105 struct btrfs_root
*root
,
106 struct btrfs_root
*log
,
107 struct btrfs_path
*path
,
108 u64 dirid
, int del_all
);
109 static void wait_log_commit(struct btrfs_root
*root
, int transid
);
112 * tree logging is a special write ahead log used to make sure that
113 * fsyncs and O_SYNCs can happen without doing full tree commits.
115 * Full tree commits are expensive because they require commonly
116 * modified blocks to be recowed, creating many dirty pages in the
117 * extent tree an 4x-6x higher write load than ext3.
119 * Instead of doing a tree commit on every fsync, we use the
120 * key ranges and transaction ids to find items for a given file or directory
121 * that have changed in this transaction. Those items are copied into
122 * a special tree (one per subvolume root), that tree is written to disk
123 * and then the fsync is considered complete.
125 * After a crash, items are copied out of the log-tree back into the
126 * subvolume tree. Any file data extents found are recorded in the extent
127 * allocation tree, and the log-tree freed.
129 * The log tree is read three times, once to pin down all the extents it is
130 * using in ram and once, once to create all the inodes logged in the tree
131 * and once to do all the other items.
135 * start a sub transaction and setup the log tree
136 * this increments the log tree writer count to make the people
137 * syncing the tree wait for us to finish
139 static int start_log_trans(struct btrfs_trans_handle
*trans
,
140 struct btrfs_root
*root
,
141 struct btrfs_log_ctx
*ctx
)
143 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
144 struct btrfs_root
*tree_root
= fs_info
->tree_root
;
145 const bool zoned
= btrfs_is_zoned(fs_info
);
147 bool created
= false;
150 * First check if the log root tree was already created. If not, create
151 * it before locking the root's log_mutex, just to keep lockdep happy.
153 if (!test_bit(BTRFS_ROOT_HAS_LOG_TREE
, &tree_root
->state
)) {
154 mutex_lock(&tree_root
->log_mutex
);
155 if (!fs_info
->log_root_tree
) {
156 ret
= btrfs_init_log_root_tree(trans
, fs_info
);
158 set_bit(BTRFS_ROOT_HAS_LOG_TREE
, &tree_root
->state
);
162 mutex_unlock(&tree_root
->log_mutex
);
167 mutex_lock(&root
->log_mutex
);
170 if (root
->log_root
) {
171 int index
= (root
->log_transid
+ 1) % 2;
173 if (btrfs_need_log_full_commit(trans
)) {
174 ret
= BTRFS_LOG_FORCE_COMMIT
;
178 if (zoned
&& atomic_read(&root
->log_commit
[index
])) {
179 wait_log_commit(root
, root
->log_transid
- 1);
183 if (!root
->log_start_pid
) {
184 clear_bit(BTRFS_ROOT_MULTI_LOG_TASKS
, &root
->state
);
185 root
->log_start_pid
= current
->pid
;
186 } else if (root
->log_start_pid
!= current
->pid
) {
187 set_bit(BTRFS_ROOT_MULTI_LOG_TASKS
, &root
->state
);
191 * This means fs_info->log_root_tree was already created
192 * for some other FS trees. Do the full commit not to mix
193 * nodes from multiple log transactions to do sequential
196 if (zoned
&& !created
) {
197 ret
= BTRFS_LOG_FORCE_COMMIT
;
201 ret
= btrfs_add_log_tree(trans
, root
);
205 set_bit(BTRFS_ROOT_HAS_LOG_TREE
, &root
->state
);
206 clear_bit(BTRFS_ROOT_MULTI_LOG_TASKS
, &root
->state
);
207 root
->log_start_pid
= current
->pid
;
210 atomic_inc(&root
->log_writers
);
211 if (!ctx
->logging_new_name
) {
212 int index
= root
->log_transid
% 2;
213 list_add_tail(&ctx
->list
, &root
->log_ctxs
[index
]);
214 ctx
->log_transid
= root
->log_transid
;
218 mutex_unlock(&root
->log_mutex
);
223 * returns 0 if there was a log transaction running and we were able
224 * to join, or returns -ENOENT if there were not transactions
227 static int join_running_log_trans(struct btrfs_root
*root
)
229 const bool zoned
= btrfs_is_zoned(root
->fs_info
);
232 if (!test_bit(BTRFS_ROOT_HAS_LOG_TREE
, &root
->state
))
235 mutex_lock(&root
->log_mutex
);
237 if (root
->log_root
) {
238 int index
= (root
->log_transid
+ 1) % 2;
241 if (zoned
&& atomic_read(&root
->log_commit
[index
])) {
242 wait_log_commit(root
, root
->log_transid
- 1);
245 atomic_inc(&root
->log_writers
);
247 mutex_unlock(&root
->log_mutex
);
252 * This either makes the current running log transaction wait
253 * until you call btrfs_end_log_trans() or it makes any future
254 * log transactions wait until you call btrfs_end_log_trans()
256 void btrfs_pin_log_trans(struct btrfs_root
*root
)
258 atomic_inc(&root
->log_writers
);
262 * indicate we're done making changes to the log tree
263 * and wake up anyone waiting to do a sync
265 void btrfs_end_log_trans(struct btrfs_root
*root
)
267 if (atomic_dec_and_test(&root
->log_writers
)) {
268 /* atomic_dec_and_test implies a barrier */
269 cond_wake_up_nomb(&root
->log_writer_wait
);
273 static void btrfs_wait_tree_block_writeback(struct extent_buffer
*buf
)
275 filemap_fdatawait_range(buf
->pages
[0]->mapping
,
276 buf
->start
, buf
->start
+ buf
->len
- 1);
280 * the walk control struct is used to pass state down the chain when
281 * processing the log tree. The stage field tells us which part
282 * of the log tree processing we are currently doing. The others
283 * are state fields used for that specific part
285 struct walk_control
{
286 /* should we free the extent on disk when done? This is used
287 * at transaction commit time while freeing a log tree
291 /* pin only walk, we record which extents on disk belong to the
296 /* what stage of the replay code we're currently in */
300 * Ignore any items from the inode currently being processed. Needs
301 * to be set every time we find a BTRFS_INODE_ITEM_KEY and we are in
302 * the LOG_WALK_REPLAY_INODES stage.
304 bool ignore_cur_inode
;
306 /* the root we are currently replaying */
307 struct btrfs_root
*replay_dest
;
309 /* the trans handle for the current replay */
310 struct btrfs_trans_handle
*trans
;
312 /* the function that gets used to process blocks we find in the
313 * tree. Note the extent_buffer might not be up to date when it is
314 * passed in, and it must be checked or read if you need the data
317 int (*process_func
)(struct btrfs_root
*log
, struct extent_buffer
*eb
,
318 struct walk_control
*wc
, u64 gen
, int level
);
322 * process_func used to pin down extents, write them or wait on them
324 static int process_one_buffer(struct btrfs_root
*log
,
325 struct extent_buffer
*eb
,
326 struct walk_control
*wc
, u64 gen
, int level
)
328 struct btrfs_fs_info
*fs_info
= log
->fs_info
;
332 * If this fs is mixed then we need to be able to process the leaves to
333 * pin down any logged extents, so we have to read the block.
335 if (btrfs_fs_incompat(fs_info
, MIXED_GROUPS
)) {
336 ret
= btrfs_read_extent_buffer(eb
, gen
, level
, NULL
);
342 ret
= btrfs_pin_extent_for_log_replay(wc
->trans
, eb
->start
,
347 if (btrfs_buffer_uptodate(eb
, gen
, 0) &&
348 btrfs_header_level(eb
) == 0)
349 ret
= btrfs_exclude_logged_extents(eb
);
354 static int do_overwrite_item(struct btrfs_trans_handle
*trans
,
355 struct btrfs_root
*root
,
356 struct btrfs_path
*path
,
357 struct extent_buffer
*eb
, int slot
,
358 struct btrfs_key
*key
)
362 u64 saved_i_size
= 0;
363 int save_old_i_size
= 0;
364 unsigned long src_ptr
;
365 unsigned long dst_ptr
;
366 int overwrite_root
= 0;
367 bool inode_item
= key
->type
== BTRFS_INODE_ITEM_KEY
;
369 if (root
->root_key
.objectid
!= BTRFS_TREE_LOG_OBJECTID
)
372 item_size
= btrfs_item_size(eb
, slot
);
373 src_ptr
= btrfs_item_ptr_offset(eb
, slot
);
375 /* Our caller must have done a search for the key for us. */
376 ASSERT(path
->nodes
[0] != NULL
);
379 * And the slot must point to the exact key or the slot where the key
380 * should be at (the first item with a key greater than 'key')
382 if (path
->slots
[0] < btrfs_header_nritems(path
->nodes
[0])) {
383 struct btrfs_key found_key
;
385 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
, path
->slots
[0]);
386 ret
= btrfs_comp_cpu_keys(&found_key
, key
);
395 u32 dst_size
= btrfs_item_size(path
->nodes
[0],
397 if (dst_size
!= item_size
)
400 if (item_size
== 0) {
401 btrfs_release_path(path
);
404 dst_copy
= kmalloc(item_size
, GFP_NOFS
);
405 src_copy
= kmalloc(item_size
, GFP_NOFS
);
406 if (!dst_copy
|| !src_copy
) {
407 btrfs_release_path(path
);
413 read_extent_buffer(eb
, src_copy
, src_ptr
, item_size
);
415 dst_ptr
= btrfs_item_ptr_offset(path
->nodes
[0], path
->slots
[0]);
416 read_extent_buffer(path
->nodes
[0], dst_copy
, dst_ptr
,
418 ret
= memcmp(dst_copy
, src_copy
, item_size
);
423 * they have the same contents, just return, this saves
424 * us from cowing blocks in the destination tree and doing
425 * extra writes that may not have been done by a previous
429 btrfs_release_path(path
);
434 * We need to load the old nbytes into the inode so when we
435 * replay the extents we've logged we get the right nbytes.
438 struct btrfs_inode_item
*item
;
442 item
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
443 struct btrfs_inode_item
);
444 nbytes
= btrfs_inode_nbytes(path
->nodes
[0], item
);
445 item
= btrfs_item_ptr(eb
, slot
,
446 struct btrfs_inode_item
);
447 btrfs_set_inode_nbytes(eb
, item
, nbytes
);
450 * If this is a directory we need to reset the i_size to
451 * 0 so that we can set it up properly when replaying
452 * the rest of the items in this log.
454 mode
= btrfs_inode_mode(eb
, item
);
456 btrfs_set_inode_size(eb
, item
, 0);
458 } else if (inode_item
) {
459 struct btrfs_inode_item
*item
;
463 * New inode, set nbytes to 0 so that the nbytes comes out
464 * properly when we replay the extents.
466 item
= btrfs_item_ptr(eb
, slot
, struct btrfs_inode_item
);
467 btrfs_set_inode_nbytes(eb
, item
, 0);
470 * If this is a directory we need to reset the i_size to 0 so
471 * that we can set it up properly when replaying the rest of
472 * the items in this log.
474 mode
= btrfs_inode_mode(eb
, item
);
476 btrfs_set_inode_size(eb
, item
, 0);
479 btrfs_release_path(path
);
480 /* try to insert the key into the destination tree */
481 path
->skip_release_on_error
= 1;
482 ret
= btrfs_insert_empty_item(trans
, root
, path
,
484 path
->skip_release_on_error
= 0;
486 /* make sure any existing item is the correct size */
487 if (ret
== -EEXIST
|| ret
== -EOVERFLOW
) {
489 found_size
= btrfs_item_size(path
->nodes
[0],
491 if (found_size
> item_size
)
492 btrfs_truncate_item(path
, item_size
, 1);
493 else if (found_size
< item_size
)
494 btrfs_extend_item(path
, item_size
- found_size
);
498 dst_ptr
= btrfs_item_ptr_offset(path
->nodes
[0],
501 /* don't overwrite an existing inode if the generation number
502 * was logged as zero. This is done when the tree logging code
503 * is just logging an inode to make sure it exists after recovery.
505 * Also, don't overwrite i_size on directories during replay.
506 * log replay inserts and removes directory items based on the
507 * state of the tree found in the subvolume, and i_size is modified
510 if (key
->type
== BTRFS_INODE_ITEM_KEY
&& ret
== -EEXIST
) {
511 struct btrfs_inode_item
*src_item
;
512 struct btrfs_inode_item
*dst_item
;
514 src_item
= (struct btrfs_inode_item
*)src_ptr
;
515 dst_item
= (struct btrfs_inode_item
*)dst_ptr
;
517 if (btrfs_inode_generation(eb
, src_item
) == 0) {
518 struct extent_buffer
*dst_eb
= path
->nodes
[0];
519 const u64 ino_size
= btrfs_inode_size(eb
, src_item
);
522 * For regular files an ino_size == 0 is used only when
523 * logging that an inode exists, as part of a directory
524 * fsync, and the inode wasn't fsynced before. In this
525 * case don't set the size of the inode in the fs/subvol
526 * tree, otherwise we would be throwing valid data away.
528 if (S_ISREG(btrfs_inode_mode(eb
, src_item
)) &&
529 S_ISREG(btrfs_inode_mode(dst_eb
, dst_item
)) &&
531 btrfs_set_inode_size(dst_eb
, dst_item
, ino_size
);
535 if (overwrite_root
&&
536 S_ISDIR(btrfs_inode_mode(eb
, src_item
)) &&
537 S_ISDIR(btrfs_inode_mode(path
->nodes
[0], dst_item
))) {
539 saved_i_size
= btrfs_inode_size(path
->nodes
[0],
544 copy_extent_buffer(path
->nodes
[0], eb
, dst_ptr
,
547 if (save_old_i_size
) {
548 struct btrfs_inode_item
*dst_item
;
549 dst_item
= (struct btrfs_inode_item
*)dst_ptr
;
550 btrfs_set_inode_size(path
->nodes
[0], dst_item
, saved_i_size
);
553 /* make sure the generation is filled in */
554 if (key
->type
== BTRFS_INODE_ITEM_KEY
) {
555 struct btrfs_inode_item
*dst_item
;
556 dst_item
= (struct btrfs_inode_item
*)dst_ptr
;
557 if (btrfs_inode_generation(path
->nodes
[0], dst_item
) == 0) {
558 btrfs_set_inode_generation(path
->nodes
[0], dst_item
,
563 btrfs_mark_buffer_dirty(path
->nodes
[0]);
564 btrfs_release_path(path
);
569 * Item overwrite used by replay and tree logging. eb, slot and key all refer
570 * to the src data we are copying out.
572 * root is the tree we are copying into, and path is a scratch
573 * path for use in this function (it should be released on entry and
574 * will be released on exit).
576 * If the key is already in the destination tree the existing item is
577 * overwritten. If the existing item isn't big enough, it is extended.
578 * If it is too large, it is truncated.
580 * If the key isn't in the destination yet, a new item is inserted.
582 static int overwrite_item(struct btrfs_trans_handle
*trans
,
583 struct btrfs_root
*root
,
584 struct btrfs_path
*path
,
585 struct extent_buffer
*eb
, int slot
,
586 struct btrfs_key
*key
)
590 /* Look for the key in the destination tree. */
591 ret
= btrfs_search_slot(NULL
, root
, key
, path
, 0, 0);
595 return do_overwrite_item(trans
, root
, path
, eb
, slot
, key
);
599 * simple helper to read an inode off the disk from a given root
600 * This can only be called for subvolume roots and not for the log
602 static noinline
struct inode
*read_one_inode(struct btrfs_root
*root
,
607 inode
= btrfs_iget(root
->fs_info
->sb
, objectid
, root
);
613 /* replays a single extent in 'eb' at 'slot' with 'key' into the
614 * subvolume 'root'. path is released on entry and should be released
617 * extents in the log tree have not been allocated out of the extent
618 * tree yet. So, this completes the allocation, taking a reference
619 * as required if the extent already exists or creating a new extent
620 * if it isn't in the extent allocation tree yet.
622 * The extent is inserted into the file, dropping any existing extents
623 * from the file that overlap the new one.
625 static noinline
int replay_one_extent(struct btrfs_trans_handle
*trans
,
626 struct btrfs_root
*root
,
627 struct btrfs_path
*path
,
628 struct extent_buffer
*eb
, int slot
,
629 struct btrfs_key
*key
)
631 struct btrfs_drop_extents_args drop_args
= { 0 };
632 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
635 u64 start
= key
->offset
;
637 struct btrfs_file_extent_item
*item
;
638 struct inode
*inode
= NULL
;
642 item
= btrfs_item_ptr(eb
, slot
, struct btrfs_file_extent_item
);
643 found_type
= btrfs_file_extent_type(eb
, item
);
645 if (found_type
== BTRFS_FILE_EXTENT_REG
||
646 found_type
== BTRFS_FILE_EXTENT_PREALLOC
) {
647 nbytes
= btrfs_file_extent_num_bytes(eb
, item
);
648 extent_end
= start
+ nbytes
;
651 * We don't add to the inodes nbytes if we are prealloc or a
654 if (btrfs_file_extent_disk_bytenr(eb
, item
) == 0)
656 } else if (found_type
== BTRFS_FILE_EXTENT_INLINE
) {
657 size
= btrfs_file_extent_ram_bytes(eb
, item
);
658 nbytes
= btrfs_file_extent_ram_bytes(eb
, item
);
659 extent_end
= ALIGN(start
+ size
,
660 fs_info
->sectorsize
);
666 inode
= read_one_inode(root
, key
->objectid
);
673 * first check to see if we already have this extent in the
674 * file. This must be done before the btrfs_drop_extents run
675 * so we don't try to drop this extent.
677 ret
= btrfs_lookup_file_extent(trans
, root
, path
,
678 btrfs_ino(BTRFS_I(inode
)), start
, 0);
681 (found_type
== BTRFS_FILE_EXTENT_REG
||
682 found_type
== BTRFS_FILE_EXTENT_PREALLOC
)) {
683 struct btrfs_file_extent_item cmp1
;
684 struct btrfs_file_extent_item cmp2
;
685 struct btrfs_file_extent_item
*existing
;
686 struct extent_buffer
*leaf
;
688 leaf
= path
->nodes
[0];
689 existing
= btrfs_item_ptr(leaf
, path
->slots
[0],
690 struct btrfs_file_extent_item
);
692 read_extent_buffer(eb
, &cmp1
, (unsigned long)item
,
694 read_extent_buffer(leaf
, &cmp2
, (unsigned long)existing
,
698 * we already have a pointer to this exact extent,
699 * we don't have to do anything
701 if (memcmp(&cmp1
, &cmp2
, sizeof(cmp1
)) == 0) {
702 btrfs_release_path(path
);
706 btrfs_release_path(path
);
708 /* drop any overlapping extents */
709 drop_args
.start
= start
;
710 drop_args
.end
= extent_end
;
711 drop_args
.drop_cache
= true;
712 ret
= btrfs_drop_extents(trans
, root
, BTRFS_I(inode
), &drop_args
);
716 if (found_type
== BTRFS_FILE_EXTENT_REG
||
717 found_type
== BTRFS_FILE_EXTENT_PREALLOC
) {
719 unsigned long dest_offset
;
720 struct btrfs_key ins
;
722 if (btrfs_file_extent_disk_bytenr(eb
, item
) == 0 &&
723 btrfs_fs_incompat(fs_info
, NO_HOLES
))
726 ret
= btrfs_insert_empty_item(trans
, root
, path
, key
,
730 dest_offset
= btrfs_item_ptr_offset(path
->nodes
[0],
732 copy_extent_buffer(path
->nodes
[0], eb
, dest_offset
,
733 (unsigned long)item
, sizeof(*item
));
735 ins
.objectid
= btrfs_file_extent_disk_bytenr(eb
, item
);
736 ins
.offset
= btrfs_file_extent_disk_num_bytes(eb
, item
);
737 ins
.type
= BTRFS_EXTENT_ITEM_KEY
;
738 offset
= key
->offset
- btrfs_file_extent_offset(eb
, item
);
741 * Manually record dirty extent, as here we did a shallow
742 * file extent item copy and skip normal backref update,
743 * but modifying extent tree all by ourselves.
744 * So need to manually record dirty extent for qgroup,
745 * as the owner of the file extent changed from log tree
746 * (doesn't affect qgroup) to fs/file tree(affects qgroup)
748 ret
= btrfs_qgroup_trace_extent(trans
,
749 btrfs_file_extent_disk_bytenr(eb
, item
),
750 btrfs_file_extent_disk_num_bytes(eb
, item
),
755 if (ins
.objectid
> 0) {
756 struct btrfs_ref ref
= { 0 };
759 LIST_HEAD(ordered_sums
);
762 * is this extent already allocated in the extent
763 * allocation tree? If so, just add a reference
765 ret
= btrfs_lookup_data_extent(fs_info
, ins
.objectid
,
769 } else if (ret
== 0) {
770 btrfs_init_generic_ref(&ref
,
771 BTRFS_ADD_DELAYED_REF
,
772 ins
.objectid
, ins
.offset
, 0);
773 btrfs_init_data_ref(&ref
,
774 root
->root_key
.objectid
,
775 key
->objectid
, offset
, 0, false);
776 ret
= btrfs_inc_extent_ref(trans
, &ref
);
781 * insert the extent pointer in the extent
784 ret
= btrfs_alloc_logged_file_extent(trans
,
785 root
->root_key
.objectid
,
786 key
->objectid
, offset
, &ins
);
790 btrfs_release_path(path
);
792 if (btrfs_file_extent_compression(eb
, item
)) {
793 csum_start
= ins
.objectid
;
794 csum_end
= csum_start
+ ins
.offset
;
796 csum_start
= ins
.objectid
+
797 btrfs_file_extent_offset(eb
, item
);
798 csum_end
= csum_start
+
799 btrfs_file_extent_num_bytes(eb
, item
);
802 ret
= btrfs_lookup_csums_range(root
->log_root
,
803 csum_start
, csum_end
- 1,
808 * Now delete all existing cums in the csum root that
809 * cover our range. We do this because we can have an
810 * extent that is completely referenced by one file
811 * extent item and partially referenced by another
812 * file extent item (like after using the clone or
813 * extent_same ioctls). In this case if we end up doing
814 * the replay of the one that partially references the
815 * extent first, and we do not do the csum deletion
816 * below, we can get 2 csum items in the csum tree that
817 * overlap each other. For example, imagine our log has
818 * the two following file extent items:
820 * key (257 EXTENT_DATA 409600)
821 * extent data disk byte 12845056 nr 102400
822 * extent data offset 20480 nr 20480 ram 102400
824 * key (257 EXTENT_DATA 819200)
825 * extent data disk byte 12845056 nr 102400
826 * extent data offset 0 nr 102400 ram 102400
828 * Where the second one fully references the 100K extent
829 * that starts at disk byte 12845056, and the log tree
830 * has a single csum item that covers the entire range
833 * key (EXTENT_CSUM EXTENT_CSUM 12845056) itemsize 100
835 * After the first file extent item is replayed, the
836 * csum tree gets the following csum item:
838 * key (EXTENT_CSUM EXTENT_CSUM 12865536) itemsize 20
840 * Which covers the 20K sub-range starting at offset 20K
841 * of our extent. Now when we replay the second file
842 * extent item, if we do not delete existing csum items
843 * that cover any of its blocks, we end up getting two
844 * csum items in our csum tree that overlap each other:
846 * key (EXTENT_CSUM EXTENT_CSUM 12845056) itemsize 100
847 * key (EXTENT_CSUM EXTENT_CSUM 12865536) itemsize 20
849 * Which is a problem, because after this anyone trying
850 * to lookup up for the checksum of any block of our
851 * extent starting at an offset of 40K or higher, will
852 * end up looking at the second csum item only, which
853 * does not contain the checksum for any block starting
854 * at offset 40K or higher of our extent.
856 while (!list_empty(&ordered_sums
)) {
857 struct btrfs_ordered_sum
*sums
;
858 struct btrfs_root
*csum_root
;
860 sums
= list_entry(ordered_sums
.next
,
861 struct btrfs_ordered_sum
,
863 csum_root
= btrfs_csum_root(fs_info
,
866 ret
= btrfs_del_csums(trans
, csum_root
,
870 ret
= btrfs_csum_file_blocks(trans
,
873 list_del(&sums
->list
);
879 btrfs_release_path(path
);
881 } else if (found_type
== BTRFS_FILE_EXTENT_INLINE
) {
882 /* inline extents are easy, we just overwrite them */
883 ret
= overwrite_item(trans
, root
, path
, eb
, slot
, key
);
888 ret
= btrfs_inode_set_file_extent_range(BTRFS_I(inode
), start
,
894 btrfs_update_inode_bytes(BTRFS_I(inode
), nbytes
, drop_args
.bytes_found
);
895 ret
= btrfs_update_inode(trans
, root
, BTRFS_I(inode
));
901 static int unlink_inode_for_log_replay(struct btrfs_trans_handle
*trans
,
902 struct btrfs_inode
*dir
,
903 struct btrfs_inode
*inode
,
909 ret
= btrfs_unlink_inode(trans
, dir
, inode
, name
, name_len
);
913 * Whenever we need to check if a name exists or not, we check the
914 * fs/subvolume tree. So after an unlink we must run delayed items, so
915 * that future checks for a name during log replay see that the name
916 * does not exists anymore.
918 return btrfs_run_delayed_items(trans
);
922 * when cleaning up conflicts between the directory names in the
923 * subvolume, directory names in the log and directory names in the
924 * inode back references, we may have to unlink inodes from directories.
926 * This is a helper function to do the unlink of a specific directory
929 static noinline
int drop_one_dir_item(struct btrfs_trans_handle
*trans
,
930 struct btrfs_path
*path
,
931 struct btrfs_inode
*dir
,
932 struct btrfs_dir_item
*di
)
934 struct btrfs_root
*root
= dir
->root
;
938 struct extent_buffer
*leaf
;
939 struct btrfs_key location
;
942 leaf
= path
->nodes
[0];
944 btrfs_dir_item_key_to_cpu(leaf
, di
, &location
);
945 name_len
= btrfs_dir_name_len(leaf
, di
);
946 name
= kmalloc(name_len
, GFP_NOFS
);
950 read_extent_buffer(leaf
, name
, (unsigned long)(di
+ 1), name_len
);
951 btrfs_release_path(path
);
953 inode
= read_one_inode(root
, location
.objectid
);
959 ret
= link_to_fixup_dir(trans
, root
, path
, location
.objectid
);
963 ret
= unlink_inode_for_log_replay(trans
, dir
, BTRFS_I(inode
), name
,
972 * See if a given name and sequence number found in an inode back reference are
973 * already in a directory and correctly point to this inode.
975 * Returns: < 0 on error, 0 if the directory entry does not exists and 1 if it
978 static noinline
int inode_in_dir(struct btrfs_root
*root
,
979 struct btrfs_path
*path
,
980 u64 dirid
, u64 objectid
, u64 index
,
981 const char *name
, int name_len
)
983 struct btrfs_dir_item
*di
;
984 struct btrfs_key location
;
987 di
= btrfs_lookup_dir_index_item(NULL
, root
, path
, dirid
,
988 index
, name
, name_len
, 0);
993 btrfs_dir_item_key_to_cpu(path
->nodes
[0], di
, &location
);
994 if (location
.objectid
!= objectid
)
1000 btrfs_release_path(path
);
1001 di
= btrfs_lookup_dir_item(NULL
, root
, path
, dirid
, name
, name_len
, 0);
1006 btrfs_dir_item_key_to_cpu(path
->nodes
[0], di
, &location
);
1007 if (location
.objectid
== objectid
)
1011 btrfs_release_path(path
);
1016 * helper function to check a log tree for a named back reference in
1017 * an inode. This is used to decide if a back reference that is
1018 * found in the subvolume conflicts with what we find in the log.
1020 * inode backreferences may have multiple refs in a single item,
1021 * during replay we process one reference at a time, and we don't
1022 * want to delete valid links to a file from the subvolume if that
1023 * link is also in the log.
1025 static noinline
int backref_in_log(struct btrfs_root
*log
,
1026 struct btrfs_key
*key
,
1028 const char *name
, int namelen
)
1030 struct btrfs_path
*path
;
1033 path
= btrfs_alloc_path();
1037 ret
= btrfs_search_slot(NULL
, log
, key
, path
, 0, 0);
1040 } else if (ret
== 1) {
1045 if (key
->type
== BTRFS_INODE_EXTREF_KEY
)
1046 ret
= !!btrfs_find_name_in_ext_backref(path
->nodes
[0],
1051 ret
= !!btrfs_find_name_in_backref(path
->nodes
[0],
1055 btrfs_free_path(path
);
1059 static inline int __add_inode_ref(struct btrfs_trans_handle
*trans
,
1060 struct btrfs_root
*root
,
1061 struct btrfs_path
*path
,
1062 struct btrfs_root
*log_root
,
1063 struct btrfs_inode
*dir
,
1064 struct btrfs_inode
*inode
,
1065 u64 inode_objectid
, u64 parent_objectid
,
1066 u64 ref_index
, char *name
, int namelen
,
1071 int victim_name_len
;
1072 struct extent_buffer
*leaf
;
1073 struct btrfs_dir_item
*di
;
1074 struct btrfs_key search_key
;
1075 struct btrfs_inode_extref
*extref
;
1078 /* Search old style refs */
1079 search_key
.objectid
= inode_objectid
;
1080 search_key
.type
= BTRFS_INODE_REF_KEY
;
1081 search_key
.offset
= parent_objectid
;
1082 ret
= btrfs_search_slot(NULL
, root
, &search_key
, path
, 0, 0);
1084 struct btrfs_inode_ref
*victim_ref
;
1086 unsigned long ptr_end
;
1088 leaf
= path
->nodes
[0];
1090 /* are we trying to overwrite a back ref for the root directory
1091 * if so, just jump out, we're done
1093 if (search_key
.objectid
== search_key
.offset
)
1096 /* check all the names in this back reference to see
1097 * if they are in the log. if so, we allow them to stay
1098 * otherwise they must be unlinked as a conflict
1100 ptr
= btrfs_item_ptr_offset(leaf
, path
->slots
[0]);
1101 ptr_end
= ptr
+ btrfs_item_size(leaf
, path
->slots
[0]);
1102 while (ptr
< ptr_end
) {
1103 victim_ref
= (struct btrfs_inode_ref
*)ptr
;
1104 victim_name_len
= btrfs_inode_ref_name_len(leaf
,
1106 victim_name
= kmalloc(victim_name_len
, GFP_NOFS
);
1110 read_extent_buffer(leaf
, victim_name
,
1111 (unsigned long)(victim_ref
+ 1),
1114 ret
= backref_in_log(log_root
, &search_key
,
1115 parent_objectid
, victim_name
,
1121 inc_nlink(&inode
->vfs_inode
);
1122 btrfs_release_path(path
);
1124 ret
= unlink_inode_for_log_replay(trans
, dir
, inode
,
1125 victim_name
, victim_name_len
);
1134 ptr
= (unsigned long)(victim_ref
+ 1) + victim_name_len
;
1138 * NOTE: we have searched root tree and checked the
1139 * corresponding ref, it does not need to check again.
1143 btrfs_release_path(path
);
1145 /* Same search but for extended refs */
1146 extref
= btrfs_lookup_inode_extref(NULL
, root
, path
, name
, namelen
,
1147 inode_objectid
, parent_objectid
, 0,
1149 if (IS_ERR(extref
)) {
1150 return PTR_ERR(extref
);
1151 } else if (extref
) {
1155 struct inode
*victim_parent
;
1157 leaf
= path
->nodes
[0];
1159 item_size
= btrfs_item_size(leaf
, path
->slots
[0]);
1160 base
= btrfs_item_ptr_offset(leaf
, path
->slots
[0]);
1162 while (cur_offset
< item_size
) {
1163 extref
= (struct btrfs_inode_extref
*)(base
+ cur_offset
);
1165 victim_name_len
= btrfs_inode_extref_name_len(leaf
, extref
);
1167 if (btrfs_inode_extref_parent(leaf
, extref
) != parent_objectid
)
1170 victim_name
= kmalloc(victim_name_len
, GFP_NOFS
);
1173 read_extent_buffer(leaf
, victim_name
, (unsigned long)&extref
->name
,
1176 search_key
.objectid
= inode_objectid
;
1177 search_key
.type
= BTRFS_INODE_EXTREF_KEY
;
1178 search_key
.offset
= btrfs_extref_hash(parent_objectid
,
1181 ret
= backref_in_log(log_root
, &search_key
,
1182 parent_objectid
, victim_name
,
1189 victim_parent
= read_one_inode(root
,
1191 if (victim_parent
) {
1192 inc_nlink(&inode
->vfs_inode
);
1193 btrfs_release_path(path
);
1195 ret
= unlink_inode_for_log_replay(trans
,
1196 BTRFS_I(victim_parent
),
1201 iput(victim_parent
);
1210 cur_offset
+= victim_name_len
+ sizeof(*extref
);
1214 btrfs_release_path(path
);
1216 /* look for a conflicting sequence number */
1217 di
= btrfs_lookup_dir_index_item(trans
, root
, path
, btrfs_ino(dir
),
1218 ref_index
, name
, namelen
, 0);
1222 ret
= drop_one_dir_item(trans
, path
, dir
, di
);
1226 btrfs_release_path(path
);
1228 /* look for a conflicting name */
1229 di
= btrfs_lookup_dir_item(trans
, root
, path
, btrfs_ino(dir
),
1234 ret
= drop_one_dir_item(trans
, path
, dir
, di
);
1238 btrfs_release_path(path
);
1243 static int extref_get_fields(struct extent_buffer
*eb
, unsigned long ref_ptr
,
1244 u32
*namelen
, char **name
, u64
*index
,
1245 u64
*parent_objectid
)
1247 struct btrfs_inode_extref
*extref
;
1249 extref
= (struct btrfs_inode_extref
*)ref_ptr
;
1251 *namelen
= btrfs_inode_extref_name_len(eb
, extref
);
1252 *name
= kmalloc(*namelen
, GFP_NOFS
);
1256 read_extent_buffer(eb
, *name
, (unsigned long)&extref
->name
,
1260 *index
= btrfs_inode_extref_index(eb
, extref
);
1261 if (parent_objectid
)
1262 *parent_objectid
= btrfs_inode_extref_parent(eb
, extref
);
1267 static int ref_get_fields(struct extent_buffer
*eb
, unsigned long ref_ptr
,
1268 u32
*namelen
, char **name
, u64
*index
)
1270 struct btrfs_inode_ref
*ref
;
1272 ref
= (struct btrfs_inode_ref
*)ref_ptr
;
1274 *namelen
= btrfs_inode_ref_name_len(eb
, ref
);
1275 *name
= kmalloc(*namelen
, GFP_NOFS
);
1279 read_extent_buffer(eb
, *name
, (unsigned long)(ref
+ 1), *namelen
);
1282 *index
= btrfs_inode_ref_index(eb
, ref
);
1288 * Take an inode reference item from the log tree and iterate all names from the
1289 * inode reference item in the subvolume tree with the same key (if it exists).
1290 * For any name that is not in the inode reference item from the log tree, do a
1291 * proper unlink of that name (that is, remove its entry from the inode
1292 * reference item and both dir index keys).
1294 static int unlink_old_inode_refs(struct btrfs_trans_handle
*trans
,
1295 struct btrfs_root
*root
,
1296 struct btrfs_path
*path
,
1297 struct btrfs_inode
*inode
,
1298 struct extent_buffer
*log_eb
,
1300 struct btrfs_key
*key
)
1303 unsigned long ref_ptr
;
1304 unsigned long ref_end
;
1305 struct extent_buffer
*eb
;
1308 btrfs_release_path(path
);
1309 ret
= btrfs_search_slot(NULL
, root
, key
, path
, 0, 0);
1317 eb
= path
->nodes
[0];
1318 ref_ptr
= btrfs_item_ptr_offset(eb
, path
->slots
[0]);
1319 ref_end
= ref_ptr
+ btrfs_item_size(eb
, path
->slots
[0]);
1320 while (ref_ptr
< ref_end
) {
1325 if (key
->type
== BTRFS_INODE_EXTREF_KEY
) {
1326 ret
= extref_get_fields(eb
, ref_ptr
, &namelen
, &name
,
1329 parent_id
= key
->offset
;
1330 ret
= ref_get_fields(eb
, ref_ptr
, &namelen
, &name
,
1336 if (key
->type
== BTRFS_INODE_EXTREF_KEY
)
1337 ret
= !!btrfs_find_name_in_ext_backref(log_eb
, log_slot
,
1341 ret
= !!btrfs_find_name_in_backref(log_eb
, log_slot
,
1347 btrfs_release_path(path
);
1348 dir
= read_one_inode(root
, parent_id
);
1354 ret
= unlink_inode_for_log_replay(trans
, BTRFS_I(dir
),
1355 inode
, name
, namelen
);
1365 if (key
->type
== BTRFS_INODE_EXTREF_KEY
)
1366 ref_ptr
+= sizeof(struct btrfs_inode_extref
);
1368 ref_ptr
+= sizeof(struct btrfs_inode_ref
);
1372 btrfs_release_path(path
);
1376 static int btrfs_inode_ref_exists(struct inode
*inode
, struct inode
*dir
,
1377 const u8 ref_type
, const char *name
,
1380 struct btrfs_key key
;
1381 struct btrfs_path
*path
;
1382 const u64 parent_id
= btrfs_ino(BTRFS_I(dir
));
1385 path
= btrfs_alloc_path();
1389 key
.objectid
= btrfs_ino(BTRFS_I(inode
));
1390 key
.type
= ref_type
;
1391 if (key
.type
== BTRFS_INODE_REF_KEY
)
1392 key
.offset
= parent_id
;
1394 key
.offset
= btrfs_extref_hash(parent_id
, name
, namelen
);
1396 ret
= btrfs_search_slot(NULL
, BTRFS_I(inode
)->root
, &key
, path
, 0, 0);
1403 if (key
.type
== BTRFS_INODE_EXTREF_KEY
)
1404 ret
= !!btrfs_find_name_in_ext_backref(path
->nodes
[0],
1405 path
->slots
[0], parent_id
, name
, namelen
);
1407 ret
= !!btrfs_find_name_in_backref(path
->nodes
[0], path
->slots
[0],
1411 btrfs_free_path(path
);
1415 static int add_link(struct btrfs_trans_handle
*trans
,
1416 struct inode
*dir
, struct inode
*inode
, const char *name
,
1417 int namelen
, u64 ref_index
)
1419 struct btrfs_root
*root
= BTRFS_I(dir
)->root
;
1420 struct btrfs_dir_item
*dir_item
;
1421 struct btrfs_key key
;
1422 struct btrfs_path
*path
;
1423 struct inode
*other_inode
= NULL
;
1426 path
= btrfs_alloc_path();
1430 dir_item
= btrfs_lookup_dir_item(NULL
, root
, path
,
1431 btrfs_ino(BTRFS_I(dir
)),
1434 btrfs_release_path(path
);
1436 } else if (IS_ERR(dir_item
)) {
1437 ret
= PTR_ERR(dir_item
);
1442 * Our inode's dentry collides with the dentry of another inode which is
1443 * in the log but not yet processed since it has a higher inode number.
1444 * So delete that other dentry.
1446 btrfs_dir_item_key_to_cpu(path
->nodes
[0], dir_item
, &key
);
1447 btrfs_release_path(path
);
1448 other_inode
= read_one_inode(root
, key
.objectid
);
1453 ret
= unlink_inode_for_log_replay(trans
, BTRFS_I(dir
), BTRFS_I(other_inode
),
1458 * If we dropped the link count to 0, bump it so that later the iput()
1459 * on the inode will not free it. We will fixup the link count later.
1461 if (other_inode
->i_nlink
== 0)
1462 set_nlink(other_inode
, 1);
1464 ret
= btrfs_add_link(trans
, BTRFS_I(dir
), BTRFS_I(inode
),
1465 name
, namelen
, 0, ref_index
);
1468 btrfs_free_path(path
);
1474 * replay one inode back reference item found in the log tree.
1475 * eb, slot and key refer to the buffer and key found in the log tree.
1476 * root is the destination we are replaying into, and path is for temp
1477 * use by this function. (it should be released on return).
1479 static noinline
int add_inode_ref(struct btrfs_trans_handle
*trans
,
1480 struct btrfs_root
*root
,
1481 struct btrfs_root
*log
,
1482 struct btrfs_path
*path
,
1483 struct extent_buffer
*eb
, int slot
,
1484 struct btrfs_key
*key
)
1486 struct inode
*dir
= NULL
;
1487 struct inode
*inode
= NULL
;
1488 unsigned long ref_ptr
;
1489 unsigned long ref_end
;
1493 int search_done
= 0;
1494 int log_ref_ver
= 0;
1495 u64 parent_objectid
;
1498 int ref_struct_size
;
1500 ref_ptr
= btrfs_item_ptr_offset(eb
, slot
);
1501 ref_end
= ref_ptr
+ btrfs_item_size(eb
, slot
);
1503 if (key
->type
== BTRFS_INODE_EXTREF_KEY
) {
1504 struct btrfs_inode_extref
*r
;
1506 ref_struct_size
= sizeof(struct btrfs_inode_extref
);
1508 r
= (struct btrfs_inode_extref
*)ref_ptr
;
1509 parent_objectid
= btrfs_inode_extref_parent(eb
, r
);
1511 ref_struct_size
= sizeof(struct btrfs_inode_ref
);
1512 parent_objectid
= key
->offset
;
1514 inode_objectid
= key
->objectid
;
1517 * it is possible that we didn't log all the parent directories
1518 * for a given inode. If we don't find the dir, just don't
1519 * copy the back ref in. The link count fixup code will take
1522 dir
= read_one_inode(root
, parent_objectid
);
1528 inode
= read_one_inode(root
, inode_objectid
);
1534 while (ref_ptr
< ref_end
) {
1536 ret
= extref_get_fields(eb
, ref_ptr
, &namelen
, &name
,
1537 &ref_index
, &parent_objectid
);
1539 * parent object can change from one array
1543 dir
= read_one_inode(root
, parent_objectid
);
1549 ret
= ref_get_fields(eb
, ref_ptr
, &namelen
, &name
,
1555 ret
= inode_in_dir(root
, path
, btrfs_ino(BTRFS_I(dir
)),
1556 btrfs_ino(BTRFS_I(inode
)), ref_index
,
1560 } else if (ret
== 0) {
1562 * look for a conflicting back reference in the
1563 * metadata. if we find one we have to unlink that name
1564 * of the file before we add our new link. Later on, we
1565 * overwrite any existing back reference, and we don't
1566 * want to create dangling pointers in the directory.
1570 ret
= __add_inode_ref(trans
, root
, path
, log
,
1575 ref_index
, name
, namelen
,
1585 * If a reference item already exists for this inode
1586 * with the same parent and name, but different index,
1587 * drop it and the corresponding directory index entries
1588 * from the parent before adding the new reference item
1589 * and dir index entries, otherwise we would fail with
1590 * -EEXIST returned from btrfs_add_link() below.
1592 ret
= btrfs_inode_ref_exists(inode
, dir
, key
->type
,
1595 ret
= unlink_inode_for_log_replay(trans
,
1600 * If we dropped the link count to 0, bump it so
1601 * that later the iput() on the inode will not
1602 * free it. We will fixup the link count later.
1604 if (!ret
&& inode
->i_nlink
== 0)
1605 set_nlink(inode
, 1);
1610 /* insert our name */
1611 ret
= add_link(trans
, dir
, inode
, name
, namelen
,
1616 ret
= btrfs_update_inode(trans
, root
, BTRFS_I(inode
));
1620 /* Else, ret == 1, we already have a perfect match, we're done. */
1622 ref_ptr
= (unsigned long)(ref_ptr
+ ref_struct_size
) + namelen
;
1632 * Before we overwrite the inode reference item in the subvolume tree
1633 * with the item from the log tree, we must unlink all names from the
1634 * parent directory that are in the subvolume's tree inode reference
1635 * item, otherwise we end up with an inconsistent subvolume tree where
1636 * dir index entries exist for a name but there is no inode reference
1637 * item with the same name.
1639 ret
= unlink_old_inode_refs(trans
, root
, path
, BTRFS_I(inode
), eb
, slot
,
1644 /* finally write the back reference in the inode */
1645 ret
= overwrite_item(trans
, root
, path
, eb
, slot
, key
);
1647 btrfs_release_path(path
);
1654 static int count_inode_extrefs(struct btrfs_root
*root
,
1655 struct btrfs_inode
*inode
, struct btrfs_path
*path
)
1659 unsigned int nlink
= 0;
1662 u64 inode_objectid
= btrfs_ino(inode
);
1665 struct btrfs_inode_extref
*extref
;
1666 struct extent_buffer
*leaf
;
1669 ret
= btrfs_find_one_extref(root
, inode_objectid
, offset
, path
,
1674 leaf
= path
->nodes
[0];
1675 item_size
= btrfs_item_size(leaf
, path
->slots
[0]);
1676 ptr
= btrfs_item_ptr_offset(leaf
, path
->slots
[0]);
1679 while (cur_offset
< item_size
) {
1680 extref
= (struct btrfs_inode_extref
*) (ptr
+ cur_offset
);
1681 name_len
= btrfs_inode_extref_name_len(leaf
, extref
);
1685 cur_offset
+= name_len
+ sizeof(*extref
);
1689 btrfs_release_path(path
);
1691 btrfs_release_path(path
);
1693 if (ret
< 0 && ret
!= -ENOENT
)
1698 static int count_inode_refs(struct btrfs_root
*root
,
1699 struct btrfs_inode
*inode
, struct btrfs_path
*path
)
1702 struct btrfs_key key
;
1703 unsigned int nlink
= 0;
1705 unsigned long ptr_end
;
1707 u64 ino
= btrfs_ino(inode
);
1710 key
.type
= BTRFS_INODE_REF_KEY
;
1711 key
.offset
= (u64
)-1;
1714 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
1718 if (path
->slots
[0] == 0)
1723 btrfs_item_key_to_cpu(path
->nodes
[0], &key
,
1725 if (key
.objectid
!= ino
||
1726 key
.type
!= BTRFS_INODE_REF_KEY
)
1728 ptr
= btrfs_item_ptr_offset(path
->nodes
[0], path
->slots
[0]);
1729 ptr_end
= ptr
+ btrfs_item_size(path
->nodes
[0],
1731 while (ptr
< ptr_end
) {
1732 struct btrfs_inode_ref
*ref
;
1734 ref
= (struct btrfs_inode_ref
*)ptr
;
1735 name_len
= btrfs_inode_ref_name_len(path
->nodes
[0],
1737 ptr
= (unsigned long)(ref
+ 1) + name_len
;
1741 if (key
.offset
== 0)
1743 if (path
->slots
[0] > 0) {
1748 btrfs_release_path(path
);
1750 btrfs_release_path(path
);
1756 * There are a few corners where the link count of the file can't
1757 * be properly maintained during replay. So, instead of adding
1758 * lots of complexity to the log code, we just scan the backrefs
1759 * for any file that has been through replay.
1761 * The scan will update the link count on the inode to reflect the
1762 * number of back refs found. If it goes down to zero, the iput
1763 * will free the inode.
1765 static noinline
int fixup_inode_link_count(struct btrfs_trans_handle
*trans
,
1766 struct btrfs_root
*root
,
1767 struct inode
*inode
)
1769 struct btrfs_path
*path
;
1772 u64 ino
= btrfs_ino(BTRFS_I(inode
));
1774 path
= btrfs_alloc_path();
1778 ret
= count_inode_refs(root
, BTRFS_I(inode
), path
);
1784 ret
= count_inode_extrefs(root
, BTRFS_I(inode
), path
);
1792 if (nlink
!= inode
->i_nlink
) {
1793 set_nlink(inode
, nlink
);
1794 ret
= btrfs_update_inode(trans
, root
, BTRFS_I(inode
));
1798 BTRFS_I(inode
)->index_cnt
= (u64
)-1;
1800 if (inode
->i_nlink
== 0) {
1801 if (S_ISDIR(inode
->i_mode
)) {
1802 ret
= replay_dir_deletes(trans
, root
, NULL
, path
,
1807 ret
= btrfs_insert_orphan_item(trans
, root
, ino
);
1813 btrfs_free_path(path
);
1817 static noinline
int fixup_inode_link_counts(struct btrfs_trans_handle
*trans
,
1818 struct btrfs_root
*root
,
1819 struct btrfs_path
*path
)
1822 struct btrfs_key key
;
1823 struct inode
*inode
;
1825 key
.objectid
= BTRFS_TREE_LOG_FIXUP_OBJECTID
;
1826 key
.type
= BTRFS_ORPHAN_ITEM_KEY
;
1827 key
.offset
= (u64
)-1;
1829 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
1835 if (path
->slots
[0] == 0)
1840 btrfs_item_key_to_cpu(path
->nodes
[0], &key
, path
->slots
[0]);
1841 if (key
.objectid
!= BTRFS_TREE_LOG_FIXUP_OBJECTID
||
1842 key
.type
!= BTRFS_ORPHAN_ITEM_KEY
)
1845 ret
= btrfs_del_item(trans
, root
, path
);
1849 btrfs_release_path(path
);
1850 inode
= read_one_inode(root
, key
.offset
);
1856 ret
= fixup_inode_link_count(trans
, root
, inode
);
1862 * fixup on a directory may create new entries,
1863 * make sure we always look for the highset possible
1866 key
.offset
= (u64
)-1;
1868 btrfs_release_path(path
);
1874 * record a given inode in the fixup dir so we can check its link
1875 * count when replay is done. The link count is incremented here
1876 * so the inode won't go away until we check it
1878 static noinline
int link_to_fixup_dir(struct btrfs_trans_handle
*trans
,
1879 struct btrfs_root
*root
,
1880 struct btrfs_path
*path
,
1883 struct btrfs_key key
;
1885 struct inode
*inode
;
1887 inode
= read_one_inode(root
, objectid
);
1891 key
.objectid
= BTRFS_TREE_LOG_FIXUP_OBJECTID
;
1892 key
.type
= BTRFS_ORPHAN_ITEM_KEY
;
1893 key
.offset
= objectid
;
1895 ret
= btrfs_insert_empty_item(trans
, root
, path
, &key
, 0);
1897 btrfs_release_path(path
);
1899 if (!inode
->i_nlink
)
1900 set_nlink(inode
, 1);
1903 ret
= btrfs_update_inode(trans
, root
, BTRFS_I(inode
));
1904 } else if (ret
== -EEXIST
) {
1913 * when replaying the log for a directory, we only insert names
1914 * for inodes that actually exist. This means an fsync on a directory
1915 * does not implicitly fsync all the new files in it
1917 static noinline
int insert_one_name(struct btrfs_trans_handle
*trans
,
1918 struct btrfs_root
*root
,
1919 u64 dirid
, u64 index
,
1920 char *name
, int name_len
,
1921 struct btrfs_key
*location
)
1923 struct inode
*inode
;
1927 inode
= read_one_inode(root
, location
->objectid
);
1931 dir
= read_one_inode(root
, dirid
);
1937 ret
= btrfs_add_link(trans
, BTRFS_I(dir
), BTRFS_I(inode
), name
,
1938 name_len
, 1, index
);
1940 /* FIXME, put inode into FIXUP list */
1947 static int delete_conflicting_dir_entry(struct btrfs_trans_handle
*trans
,
1948 struct btrfs_inode
*dir
,
1949 struct btrfs_path
*path
,
1950 struct btrfs_dir_item
*dst_di
,
1951 const struct btrfs_key
*log_key
,
1955 struct btrfs_key found_key
;
1957 btrfs_dir_item_key_to_cpu(path
->nodes
[0], dst_di
, &found_key
);
1958 /* The existing dentry points to the same inode, don't delete it. */
1959 if (found_key
.objectid
== log_key
->objectid
&&
1960 found_key
.type
== log_key
->type
&&
1961 found_key
.offset
== log_key
->offset
&&
1962 btrfs_dir_type(path
->nodes
[0], dst_di
) == log_type
)
1966 * Don't drop the conflicting directory entry if the inode for the new
1967 * entry doesn't exist.
1972 return drop_one_dir_item(trans
, path
, dir
, dst_di
);
1976 * take a single entry in a log directory item and replay it into
1979 * if a conflicting item exists in the subdirectory already,
1980 * the inode it points to is unlinked and put into the link count
1983 * If a name from the log points to a file or directory that does
1984 * not exist in the FS, it is skipped. fsyncs on directories
1985 * do not force down inodes inside that directory, just changes to the
1986 * names or unlinks in a directory.
1988 * Returns < 0 on error, 0 if the name wasn't replayed (dentry points to a
1989 * non-existing inode) and 1 if the name was replayed.
1991 static noinline
int replay_one_name(struct btrfs_trans_handle
*trans
,
1992 struct btrfs_root
*root
,
1993 struct btrfs_path
*path
,
1994 struct extent_buffer
*eb
,
1995 struct btrfs_dir_item
*di
,
1996 struct btrfs_key
*key
)
2000 struct btrfs_dir_item
*dir_dst_di
;
2001 struct btrfs_dir_item
*index_dst_di
;
2002 bool dir_dst_matches
= false;
2003 bool index_dst_matches
= false;
2004 struct btrfs_key log_key
;
2005 struct btrfs_key search_key
;
2010 bool update_size
= true;
2011 bool name_added
= false;
2013 dir
= read_one_inode(root
, key
->objectid
);
2017 name_len
= btrfs_dir_name_len(eb
, di
);
2018 name
= kmalloc(name_len
, GFP_NOFS
);
2024 log_type
= btrfs_dir_type(eb
, di
);
2025 read_extent_buffer(eb
, name
, (unsigned long)(di
+ 1),
2028 btrfs_dir_item_key_to_cpu(eb
, di
, &log_key
);
2029 ret
= btrfs_lookup_inode(trans
, root
, path
, &log_key
, 0);
2030 btrfs_release_path(path
);
2033 exists
= (ret
== 0);
2036 dir_dst_di
= btrfs_lookup_dir_item(trans
, root
, path
, key
->objectid
,
2038 if (IS_ERR(dir_dst_di
)) {
2039 ret
= PTR_ERR(dir_dst_di
);
2041 } else if (dir_dst_di
) {
2042 ret
= delete_conflicting_dir_entry(trans
, BTRFS_I(dir
), path
,
2043 dir_dst_di
, &log_key
, log_type
,
2047 dir_dst_matches
= (ret
== 1);
2050 btrfs_release_path(path
);
2052 index_dst_di
= btrfs_lookup_dir_index_item(trans
, root
, path
,
2053 key
->objectid
, key
->offset
,
2055 if (IS_ERR(index_dst_di
)) {
2056 ret
= PTR_ERR(index_dst_di
);
2058 } else if (index_dst_di
) {
2059 ret
= delete_conflicting_dir_entry(trans
, BTRFS_I(dir
), path
,
2060 index_dst_di
, &log_key
,
2064 index_dst_matches
= (ret
== 1);
2067 btrfs_release_path(path
);
2069 if (dir_dst_matches
&& index_dst_matches
) {
2071 update_size
= false;
2076 * Check if the inode reference exists in the log for the given name,
2077 * inode and parent inode
2079 search_key
.objectid
= log_key
.objectid
;
2080 search_key
.type
= BTRFS_INODE_REF_KEY
;
2081 search_key
.offset
= key
->objectid
;
2082 ret
= backref_in_log(root
->log_root
, &search_key
, 0, name
, name_len
);
2086 /* The dentry will be added later. */
2088 update_size
= false;
2092 search_key
.objectid
= log_key
.objectid
;
2093 search_key
.type
= BTRFS_INODE_EXTREF_KEY
;
2094 search_key
.offset
= key
->objectid
;
2095 ret
= backref_in_log(root
->log_root
, &search_key
, key
->objectid
, name
,
2100 /* The dentry will be added later. */
2102 update_size
= false;
2105 btrfs_release_path(path
);
2106 ret
= insert_one_name(trans
, root
, key
->objectid
, key
->offset
,
2107 name
, name_len
, &log_key
);
2108 if (ret
&& ret
!= -ENOENT
&& ret
!= -EEXIST
)
2112 update_size
= false;
2116 if (!ret
&& update_size
) {
2117 btrfs_i_size_write(BTRFS_I(dir
), dir
->i_size
+ name_len
* 2);
2118 ret
= btrfs_update_inode(trans
, root
, BTRFS_I(dir
));
2122 if (!ret
&& name_added
)
2127 /* Replay one dir item from a BTRFS_DIR_INDEX_KEY key. */
2128 static noinline
int replay_one_dir_item(struct btrfs_trans_handle
*trans
,
2129 struct btrfs_root
*root
,
2130 struct btrfs_path
*path
,
2131 struct extent_buffer
*eb
, int slot
,
2132 struct btrfs_key
*key
)
2135 struct btrfs_dir_item
*di
;
2137 /* We only log dir index keys, which only contain a single dir item. */
2138 ASSERT(key
->type
== BTRFS_DIR_INDEX_KEY
);
2140 di
= btrfs_item_ptr(eb
, slot
, struct btrfs_dir_item
);
2141 ret
= replay_one_name(trans
, root
, path
, eb
, di
, key
);
2146 * If this entry refers to a non-directory (directories can not have a
2147 * link count > 1) and it was added in the transaction that was not
2148 * committed, make sure we fixup the link count of the inode the entry
2149 * points to. Otherwise something like the following would result in a
2150 * directory pointing to an inode with a wrong link that does not account
2151 * for this dir entry:
2158 * ln testdir/bar testdir/bar_link
2159 * ln testdir/foo testdir/foo_link
2160 * xfs_io -c "fsync" testdir/bar
2164 * mount fs, log replay happens
2166 * File foo would remain with a link count of 1 when it has two entries
2167 * pointing to it in the directory testdir. This would make it impossible
2168 * to ever delete the parent directory has it would result in stale
2169 * dentries that can never be deleted.
2171 if (ret
== 1 && btrfs_dir_type(eb
, di
) != BTRFS_FT_DIR
) {
2172 struct btrfs_path
*fixup_path
;
2173 struct btrfs_key di_key
;
2175 fixup_path
= btrfs_alloc_path();
2179 btrfs_dir_item_key_to_cpu(eb
, di
, &di_key
);
2180 ret
= link_to_fixup_dir(trans
, root
, fixup_path
, di_key
.objectid
);
2181 btrfs_free_path(fixup_path
);
2188 * directory replay has two parts. There are the standard directory
2189 * items in the log copied from the subvolume, and range items
2190 * created in the log while the subvolume was logged.
2192 * The range items tell us which parts of the key space the log
2193 * is authoritative for. During replay, if a key in the subvolume
2194 * directory is in a logged range item, but not actually in the log
2195 * that means it was deleted from the directory before the fsync
2196 * and should be removed.
2198 static noinline
int find_dir_range(struct btrfs_root
*root
,
2199 struct btrfs_path
*path
,
2201 u64
*start_ret
, u64
*end_ret
)
2203 struct btrfs_key key
;
2205 struct btrfs_dir_log_item
*item
;
2209 if (*start_ret
== (u64
)-1)
2212 key
.objectid
= dirid
;
2213 key
.type
= BTRFS_DIR_LOG_INDEX_KEY
;
2214 key
.offset
= *start_ret
;
2216 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
2220 if (path
->slots
[0] == 0)
2225 btrfs_item_key_to_cpu(path
->nodes
[0], &key
, path
->slots
[0]);
2227 if (key
.type
!= BTRFS_DIR_LOG_INDEX_KEY
|| key
.objectid
!= dirid
) {
2231 item
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
2232 struct btrfs_dir_log_item
);
2233 found_end
= btrfs_dir_log_end(path
->nodes
[0], item
);
2235 if (*start_ret
>= key
.offset
&& *start_ret
<= found_end
) {
2237 *start_ret
= key
.offset
;
2238 *end_ret
= found_end
;
2243 /* check the next slot in the tree to see if it is a valid item */
2244 nritems
= btrfs_header_nritems(path
->nodes
[0]);
2246 if (path
->slots
[0] >= nritems
) {
2247 ret
= btrfs_next_leaf(root
, path
);
2252 btrfs_item_key_to_cpu(path
->nodes
[0], &key
, path
->slots
[0]);
2254 if (key
.type
!= BTRFS_DIR_LOG_INDEX_KEY
|| key
.objectid
!= dirid
) {
2258 item
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
2259 struct btrfs_dir_log_item
);
2260 found_end
= btrfs_dir_log_end(path
->nodes
[0], item
);
2261 *start_ret
= key
.offset
;
2262 *end_ret
= found_end
;
2265 btrfs_release_path(path
);
2270 * this looks for a given directory item in the log. If the directory
2271 * item is not in the log, the item is removed and the inode it points
2274 static noinline
int check_item_in_log(struct btrfs_trans_handle
*trans
,
2275 struct btrfs_root
*log
,
2276 struct btrfs_path
*path
,
2277 struct btrfs_path
*log_path
,
2279 struct btrfs_key
*dir_key
)
2281 struct btrfs_root
*root
= BTRFS_I(dir
)->root
;
2283 struct extent_buffer
*eb
;
2285 struct btrfs_dir_item
*di
;
2288 struct inode
*inode
= NULL
;
2289 struct btrfs_key location
;
2292 * Currently we only log dir index keys. Even if we replay a log created
2293 * by an older kernel that logged both dir index and dir item keys, all
2294 * we need to do is process the dir index keys, we (and our caller) can
2295 * safely ignore dir item keys (key type BTRFS_DIR_ITEM_KEY).
2297 ASSERT(dir_key
->type
== BTRFS_DIR_INDEX_KEY
);
2299 eb
= path
->nodes
[0];
2300 slot
= path
->slots
[0];
2301 di
= btrfs_item_ptr(eb
, slot
, struct btrfs_dir_item
);
2302 name_len
= btrfs_dir_name_len(eb
, di
);
2303 name
= kmalloc(name_len
, GFP_NOFS
);
2309 read_extent_buffer(eb
, name
, (unsigned long)(di
+ 1), name_len
);
2312 struct btrfs_dir_item
*log_di
;
2314 log_di
= btrfs_lookup_dir_index_item(trans
, log
, log_path
,
2318 if (IS_ERR(log_di
)) {
2319 ret
= PTR_ERR(log_di
);
2321 } else if (log_di
) {
2322 /* The dentry exists in the log, we have nothing to do. */
2328 btrfs_dir_item_key_to_cpu(eb
, di
, &location
);
2329 btrfs_release_path(path
);
2330 btrfs_release_path(log_path
);
2331 inode
= read_one_inode(root
, location
.objectid
);
2337 ret
= link_to_fixup_dir(trans
, root
, path
, location
.objectid
);
2342 ret
= unlink_inode_for_log_replay(trans
, BTRFS_I(dir
), BTRFS_I(inode
),
2345 * Unlike dir item keys, dir index keys can only have one name (entry) in
2346 * them, as there are no key collisions since each key has a unique offset
2347 * (an index number), so we're done.
2350 btrfs_release_path(path
);
2351 btrfs_release_path(log_path
);
2357 static int replay_xattr_deletes(struct btrfs_trans_handle
*trans
,
2358 struct btrfs_root
*root
,
2359 struct btrfs_root
*log
,
2360 struct btrfs_path
*path
,
2363 struct btrfs_key search_key
;
2364 struct btrfs_path
*log_path
;
2369 log_path
= btrfs_alloc_path();
2373 search_key
.objectid
= ino
;
2374 search_key
.type
= BTRFS_XATTR_ITEM_KEY
;
2375 search_key
.offset
= 0;
2377 ret
= btrfs_search_slot(NULL
, root
, &search_key
, path
, 0, 0);
2381 nritems
= btrfs_header_nritems(path
->nodes
[0]);
2382 for (i
= path
->slots
[0]; i
< nritems
; i
++) {
2383 struct btrfs_key key
;
2384 struct btrfs_dir_item
*di
;
2385 struct btrfs_dir_item
*log_di
;
2389 btrfs_item_key_to_cpu(path
->nodes
[0], &key
, i
);
2390 if (key
.objectid
!= ino
|| key
.type
!= BTRFS_XATTR_ITEM_KEY
) {
2395 di
= btrfs_item_ptr(path
->nodes
[0], i
, struct btrfs_dir_item
);
2396 total_size
= btrfs_item_size(path
->nodes
[0], i
);
2398 while (cur
< total_size
) {
2399 u16 name_len
= btrfs_dir_name_len(path
->nodes
[0], di
);
2400 u16 data_len
= btrfs_dir_data_len(path
->nodes
[0], di
);
2401 u32 this_len
= sizeof(*di
) + name_len
+ data_len
;
2404 name
= kmalloc(name_len
, GFP_NOFS
);
2409 read_extent_buffer(path
->nodes
[0], name
,
2410 (unsigned long)(di
+ 1), name_len
);
2412 log_di
= btrfs_lookup_xattr(NULL
, log
, log_path
, ino
,
2414 btrfs_release_path(log_path
);
2416 /* Doesn't exist in log tree, so delete it. */
2417 btrfs_release_path(path
);
2418 di
= btrfs_lookup_xattr(trans
, root
, path
, ino
,
2419 name
, name_len
, -1);
2426 ret
= btrfs_delete_one_dir_name(trans
, root
,
2430 btrfs_release_path(path
);
2435 if (IS_ERR(log_di
)) {
2436 ret
= PTR_ERR(log_di
);
2440 di
= (struct btrfs_dir_item
*)((char *)di
+ this_len
);
2443 ret
= btrfs_next_leaf(root
, path
);
2449 btrfs_free_path(log_path
);
2450 btrfs_release_path(path
);
2456 * deletion replay happens before we copy any new directory items
2457 * out of the log or out of backreferences from inodes. It
2458 * scans the log to find ranges of keys that log is authoritative for,
2459 * and then scans the directory to find items in those ranges that are
2460 * not present in the log.
2462 * Anything we don't find in the log is unlinked and removed from the
2465 static noinline
int replay_dir_deletes(struct btrfs_trans_handle
*trans
,
2466 struct btrfs_root
*root
,
2467 struct btrfs_root
*log
,
2468 struct btrfs_path
*path
,
2469 u64 dirid
, int del_all
)
2474 struct btrfs_key dir_key
;
2475 struct btrfs_key found_key
;
2476 struct btrfs_path
*log_path
;
2479 dir_key
.objectid
= dirid
;
2480 dir_key
.type
= BTRFS_DIR_INDEX_KEY
;
2481 log_path
= btrfs_alloc_path();
2485 dir
= read_one_inode(root
, dirid
);
2486 /* it isn't an error if the inode isn't there, that can happen
2487 * because we replay the deletes before we copy in the inode item
2491 btrfs_free_path(log_path
);
2499 range_end
= (u64
)-1;
2501 ret
= find_dir_range(log
, path
, dirid
,
2502 &range_start
, &range_end
);
2509 dir_key
.offset
= range_start
;
2512 ret
= btrfs_search_slot(NULL
, root
, &dir_key
, path
,
2517 nritems
= btrfs_header_nritems(path
->nodes
[0]);
2518 if (path
->slots
[0] >= nritems
) {
2519 ret
= btrfs_next_leaf(root
, path
);
2525 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
,
2527 if (found_key
.objectid
!= dirid
||
2528 found_key
.type
!= dir_key
.type
) {
2533 if (found_key
.offset
> range_end
)
2536 ret
= check_item_in_log(trans
, log
, path
,
2541 if (found_key
.offset
== (u64
)-1)
2543 dir_key
.offset
= found_key
.offset
+ 1;
2545 btrfs_release_path(path
);
2546 if (range_end
== (u64
)-1)
2548 range_start
= range_end
+ 1;
2552 btrfs_release_path(path
);
2553 btrfs_free_path(log_path
);
2559 * the process_func used to replay items from the log tree. This
2560 * gets called in two different stages. The first stage just looks
2561 * for inodes and makes sure they are all copied into the subvolume.
2563 * The second stage copies all the other item types from the log into
2564 * the subvolume. The two stage approach is slower, but gets rid of
2565 * lots of complexity around inodes referencing other inodes that exist
2566 * only in the log (references come from either directory items or inode
2569 static int replay_one_buffer(struct btrfs_root
*log
, struct extent_buffer
*eb
,
2570 struct walk_control
*wc
, u64 gen
, int level
)
2573 struct btrfs_path
*path
;
2574 struct btrfs_root
*root
= wc
->replay_dest
;
2575 struct btrfs_key key
;
2579 ret
= btrfs_read_extent_buffer(eb
, gen
, level
, NULL
);
2583 level
= btrfs_header_level(eb
);
2588 path
= btrfs_alloc_path();
2592 nritems
= btrfs_header_nritems(eb
);
2593 for (i
= 0; i
< nritems
; i
++) {
2594 btrfs_item_key_to_cpu(eb
, &key
, i
);
2596 /* inode keys are done during the first stage */
2597 if (key
.type
== BTRFS_INODE_ITEM_KEY
&&
2598 wc
->stage
== LOG_WALK_REPLAY_INODES
) {
2599 struct btrfs_inode_item
*inode_item
;
2602 inode_item
= btrfs_item_ptr(eb
, i
,
2603 struct btrfs_inode_item
);
2605 * If we have a tmpfile (O_TMPFILE) that got fsync'ed
2606 * and never got linked before the fsync, skip it, as
2607 * replaying it is pointless since it would be deleted
2608 * later. We skip logging tmpfiles, but it's always
2609 * possible we are replaying a log created with a kernel
2610 * that used to log tmpfiles.
2612 if (btrfs_inode_nlink(eb
, inode_item
) == 0) {
2613 wc
->ignore_cur_inode
= true;
2616 wc
->ignore_cur_inode
= false;
2618 ret
= replay_xattr_deletes(wc
->trans
, root
, log
,
2619 path
, key
.objectid
);
2622 mode
= btrfs_inode_mode(eb
, inode_item
);
2623 if (S_ISDIR(mode
)) {
2624 ret
= replay_dir_deletes(wc
->trans
,
2625 root
, log
, path
, key
.objectid
, 0);
2629 ret
= overwrite_item(wc
->trans
, root
, path
,
2635 * Before replaying extents, truncate the inode to its
2636 * size. We need to do it now and not after log replay
2637 * because before an fsync we can have prealloc extents
2638 * added beyond the inode's i_size. If we did it after,
2639 * through orphan cleanup for example, we would drop
2640 * those prealloc extents just after replaying them.
2642 if (S_ISREG(mode
)) {
2643 struct btrfs_drop_extents_args drop_args
= { 0 };
2644 struct inode
*inode
;
2647 inode
= read_one_inode(root
, key
.objectid
);
2652 from
= ALIGN(i_size_read(inode
),
2653 root
->fs_info
->sectorsize
);
2654 drop_args
.start
= from
;
2655 drop_args
.end
= (u64
)-1;
2656 drop_args
.drop_cache
= true;
2657 ret
= btrfs_drop_extents(wc
->trans
, root
,
2661 inode_sub_bytes(inode
,
2662 drop_args
.bytes_found
);
2663 /* Update the inode's nbytes. */
2664 ret
= btrfs_update_inode(wc
->trans
,
2665 root
, BTRFS_I(inode
));
2672 ret
= link_to_fixup_dir(wc
->trans
, root
,
2673 path
, key
.objectid
);
2678 if (wc
->ignore_cur_inode
)
2681 if (key
.type
== BTRFS_DIR_INDEX_KEY
&&
2682 wc
->stage
== LOG_WALK_REPLAY_DIR_INDEX
) {
2683 ret
= replay_one_dir_item(wc
->trans
, root
, path
,
2689 if (wc
->stage
< LOG_WALK_REPLAY_ALL
)
2692 /* these keys are simply copied */
2693 if (key
.type
== BTRFS_XATTR_ITEM_KEY
) {
2694 ret
= overwrite_item(wc
->trans
, root
, path
,
2698 } else if (key
.type
== BTRFS_INODE_REF_KEY
||
2699 key
.type
== BTRFS_INODE_EXTREF_KEY
) {
2700 ret
= add_inode_ref(wc
->trans
, root
, log
, path
,
2702 if (ret
&& ret
!= -ENOENT
)
2705 } else if (key
.type
== BTRFS_EXTENT_DATA_KEY
) {
2706 ret
= replay_one_extent(wc
->trans
, root
, path
,
2712 * We don't log BTRFS_DIR_ITEM_KEY keys anymore, only the
2713 * BTRFS_DIR_INDEX_KEY items which we use to derive the
2714 * BTRFS_DIR_ITEM_KEY items. If we are replaying a log from an
2715 * older kernel with such keys, ignore them.
2718 btrfs_free_path(path
);
2723 * Correctly adjust the reserved bytes occupied by a log tree extent buffer
2725 static void unaccount_log_buffer(struct btrfs_fs_info
*fs_info
, u64 start
)
2727 struct btrfs_block_group
*cache
;
2729 cache
= btrfs_lookup_block_group(fs_info
, start
);
2731 btrfs_err(fs_info
, "unable to find block group for %llu", start
);
2735 spin_lock(&cache
->space_info
->lock
);
2736 spin_lock(&cache
->lock
);
2737 cache
->reserved
-= fs_info
->nodesize
;
2738 cache
->space_info
->bytes_reserved
-= fs_info
->nodesize
;
2739 spin_unlock(&cache
->lock
);
2740 spin_unlock(&cache
->space_info
->lock
);
2742 btrfs_put_block_group(cache
);
2745 static noinline
int walk_down_log_tree(struct btrfs_trans_handle
*trans
,
2746 struct btrfs_root
*root
,
2747 struct btrfs_path
*path
, int *level
,
2748 struct walk_control
*wc
)
2750 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
2753 struct extent_buffer
*next
;
2754 struct extent_buffer
*cur
;
2758 while (*level
> 0) {
2759 struct btrfs_key first_key
;
2761 cur
= path
->nodes
[*level
];
2763 WARN_ON(btrfs_header_level(cur
) != *level
);
2765 if (path
->slots
[*level
] >=
2766 btrfs_header_nritems(cur
))
2769 bytenr
= btrfs_node_blockptr(cur
, path
->slots
[*level
]);
2770 ptr_gen
= btrfs_node_ptr_generation(cur
, path
->slots
[*level
]);
2771 btrfs_node_key_to_cpu(cur
, &first_key
, path
->slots
[*level
]);
2772 blocksize
= fs_info
->nodesize
;
2774 next
= btrfs_find_create_tree_block(fs_info
, bytenr
,
2775 btrfs_header_owner(cur
),
2778 return PTR_ERR(next
);
2781 ret
= wc
->process_func(root
, next
, wc
, ptr_gen
,
2784 free_extent_buffer(next
);
2788 path
->slots
[*level
]++;
2790 ret
= btrfs_read_extent_buffer(next
, ptr_gen
,
2791 *level
- 1, &first_key
);
2793 free_extent_buffer(next
);
2798 btrfs_tree_lock(next
);
2799 btrfs_clean_tree_block(next
);
2800 btrfs_wait_tree_block_writeback(next
);
2801 btrfs_tree_unlock(next
);
2802 ret
= btrfs_pin_reserved_extent(trans
,
2805 free_extent_buffer(next
);
2808 btrfs_redirty_list_add(
2809 trans
->transaction
, next
);
2811 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY
, &next
->bflags
))
2812 clear_extent_buffer_dirty(next
);
2813 unaccount_log_buffer(fs_info
, bytenr
);
2816 free_extent_buffer(next
);
2819 ret
= btrfs_read_extent_buffer(next
, ptr_gen
, *level
- 1, &first_key
);
2821 free_extent_buffer(next
);
2825 if (path
->nodes
[*level
-1])
2826 free_extent_buffer(path
->nodes
[*level
-1]);
2827 path
->nodes
[*level
-1] = next
;
2828 *level
= btrfs_header_level(next
);
2829 path
->slots
[*level
] = 0;
2832 path
->slots
[*level
] = btrfs_header_nritems(path
->nodes
[*level
]);
2838 static noinline
int walk_up_log_tree(struct btrfs_trans_handle
*trans
,
2839 struct btrfs_root
*root
,
2840 struct btrfs_path
*path
, int *level
,
2841 struct walk_control
*wc
)
2843 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
2848 for (i
= *level
; i
< BTRFS_MAX_LEVEL
- 1 && path
->nodes
[i
]; i
++) {
2849 slot
= path
->slots
[i
];
2850 if (slot
+ 1 < btrfs_header_nritems(path
->nodes
[i
])) {
2853 WARN_ON(*level
== 0);
2856 ret
= wc
->process_func(root
, path
->nodes
[*level
], wc
,
2857 btrfs_header_generation(path
->nodes
[*level
]),
2863 struct extent_buffer
*next
;
2865 next
= path
->nodes
[*level
];
2868 btrfs_tree_lock(next
);
2869 btrfs_clean_tree_block(next
);
2870 btrfs_wait_tree_block_writeback(next
);
2871 btrfs_tree_unlock(next
);
2872 ret
= btrfs_pin_reserved_extent(trans
,
2873 path
->nodes
[*level
]->start
,
2874 path
->nodes
[*level
]->len
);
2877 btrfs_redirty_list_add(trans
->transaction
,
2880 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY
, &next
->bflags
))
2881 clear_extent_buffer_dirty(next
);
2883 unaccount_log_buffer(fs_info
,
2884 path
->nodes
[*level
]->start
);
2887 free_extent_buffer(path
->nodes
[*level
]);
2888 path
->nodes
[*level
] = NULL
;
2896 * drop the reference count on the tree rooted at 'snap'. This traverses
2897 * the tree freeing any blocks that have a ref count of zero after being
2900 static int walk_log_tree(struct btrfs_trans_handle
*trans
,
2901 struct btrfs_root
*log
, struct walk_control
*wc
)
2903 struct btrfs_fs_info
*fs_info
= log
->fs_info
;
2907 struct btrfs_path
*path
;
2910 path
= btrfs_alloc_path();
2914 level
= btrfs_header_level(log
->node
);
2916 path
->nodes
[level
] = log
->node
;
2917 atomic_inc(&log
->node
->refs
);
2918 path
->slots
[level
] = 0;
2921 wret
= walk_down_log_tree(trans
, log
, path
, &level
, wc
);
2929 wret
= walk_up_log_tree(trans
, log
, path
, &level
, wc
);
2938 /* was the root node processed? if not, catch it here */
2939 if (path
->nodes
[orig_level
]) {
2940 ret
= wc
->process_func(log
, path
->nodes
[orig_level
], wc
,
2941 btrfs_header_generation(path
->nodes
[orig_level
]),
2946 struct extent_buffer
*next
;
2948 next
= path
->nodes
[orig_level
];
2951 btrfs_tree_lock(next
);
2952 btrfs_clean_tree_block(next
);
2953 btrfs_wait_tree_block_writeback(next
);
2954 btrfs_tree_unlock(next
);
2955 ret
= btrfs_pin_reserved_extent(trans
,
2956 next
->start
, next
->len
);
2959 btrfs_redirty_list_add(trans
->transaction
, next
);
2961 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY
, &next
->bflags
))
2962 clear_extent_buffer_dirty(next
);
2963 unaccount_log_buffer(fs_info
, next
->start
);
2969 btrfs_free_path(path
);
2974 * helper function to update the item for a given subvolumes log root
2975 * in the tree of log roots
2977 static int update_log_root(struct btrfs_trans_handle
*trans
,
2978 struct btrfs_root
*log
,
2979 struct btrfs_root_item
*root_item
)
2981 struct btrfs_fs_info
*fs_info
= log
->fs_info
;
2984 if (log
->log_transid
== 1) {
2985 /* insert root item on the first sync */
2986 ret
= btrfs_insert_root(trans
, fs_info
->log_root_tree
,
2987 &log
->root_key
, root_item
);
2989 ret
= btrfs_update_root(trans
, fs_info
->log_root_tree
,
2990 &log
->root_key
, root_item
);
2995 static void wait_log_commit(struct btrfs_root
*root
, int transid
)
2998 int index
= transid
% 2;
3001 * we only allow two pending log transactions at a time,
3002 * so we know that if ours is more than 2 older than the
3003 * current transaction, we're done
3006 prepare_to_wait(&root
->log_commit_wait
[index
],
3007 &wait
, TASK_UNINTERRUPTIBLE
);
3009 if (!(root
->log_transid_committed
< transid
&&
3010 atomic_read(&root
->log_commit
[index
])))
3013 mutex_unlock(&root
->log_mutex
);
3015 mutex_lock(&root
->log_mutex
);
3017 finish_wait(&root
->log_commit_wait
[index
], &wait
);
3020 static void wait_for_writer(struct btrfs_root
*root
)
3025 prepare_to_wait(&root
->log_writer_wait
, &wait
,
3026 TASK_UNINTERRUPTIBLE
);
3027 if (!atomic_read(&root
->log_writers
))
3030 mutex_unlock(&root
->log_mutex
);
3032 mutex_lock(&root
->log_mutex
);
3034 finish_wait(&root
->log_writer_wait
, &wait
);
3037 static inline void btrfs_remove_log_ctx(struct btrfs_root
*root
,
3038 struct btrfs_log_ctx
*ctx
)
3040 mutex_lock(&root
->log_mutex
);
3041 list_del_init(&ctx
->list
);
3042 mutex_unlock(&root
->log_mutex
);
3046 * Invoked in log mutex context, or be sure there is no other task which
3047 * can access the list.
3049 static inline void btrfs_remove_all_log_ctxs(struct btrfs_root
*root
,
3050 int index
, int error
)
3052 struct btrfs_log_ctx
*ctx
;
3053 struct btrfs_log_ctx
*safe
;
3055 list_for_each_entry_safe(ctx
, safe
, &root
->log_ctxs
[index
], list
) {
3056 list_del_init(&ctx
->list
);
3057 ctx
->log_ret
= error
;
3062 * btrfs_sync_log does sends a given tree log down to the disk and
3063 * updates the super blocks to record it. When this call is done,
3064 * you know that any inodes previously logged are safely on disk only
3067 * Any other return value means you need to call btrfs_commit_transaction.
3068 * Some of the edge cases for fsyncing directories that have had unlinks
3069 * or renames done in the past mean that sometimes the only safe
3070 * fsync is to commit the whole FS. When btrfs_sync_log returns -EAGAIN,
3071 * that has happened.
3073 int btrfs_sync_log(struct btrfs_trans_handle
*trans
,
3074 struct btrfs_root
*root
, struct btrfs_log_ctx
*ctx
)
3080 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
3081 struct btrfs_root
*log
= root
->log_root
;
3082 struct btrfs_root
*log_root_tree
= fs_info
->log_root_tree
;
3083 struct btrfs_root_item new_root_item
;
3084 int log_transid
= 0;
3085 struct btrfs_log_ctx root_log_ctx
;
3086 struct blk_plug plug
;
3090 mutex_lock(&root
->log_mutex
);
3091 log_transid
= ctx
->log_transid
;
3092 if (root
->log_transid_committed
>= log_transid
) {
3093 mutex_unlock(&root
->log_mutex
);
3094 return ctx
->log_ret
;
3097 index1
= log_transid
% 2;
3098 if (atomic_read(&root
->log_commit
[index1
])) {
3099 wait_log_commit(root
, log_transid
);
3100 mutex_unlock(&root
->log_mutex
);
3101 return ctx
->log_ret
;
3103 ASSERT(log_transid
== root
->log_transid
);
3104 atomic_set(&root
->log_commit
[index1
], 1);
3106 /* wait for previous tree log sync to complete */
3107 if (atomic_read(&root
->log_commit
[(index1
+ 1) % 2]))
3108 wait_log_commit(root
, log_transid
- 1);
3111 int batch
= atomic_read(&root
->log_batch
);
3112 /* when we're on an ssd, just kick the log commit out */
3113 if (!btrfs_test_opt(fs_info
, SSD
) &&
3114 test_bit(BTRFS_ROOT_MULTI_LOG_TASKS
, &root
->state
)) {
3115 mutex_unlock(&root
->log_mutex
);
3116 schedule_timeout_uninterruptible(1);
3117 mutex_lock(&root
->log_mutex
);
3119 wait_for_writer(root
);
3120 if (batch
== atomic_read(&root
->log_batch
))
3124 /* bail out if we need to do a full commit */
3125 if (btrfs_need_log_full_commit(trans
)) {
3126 ret
= BTRFS_LOG_FORCE_COMMIT
;
3127 mutex_unlock(&root
->log_mutex
);
3131 if (log_transid
% 2 == 0)
3132 mark
= EXTENT_DIRTY
;
3136 /* we start IO on all the marked extents here, but we don't actually
3137 * wait for them until later.
3139 blk_start_plug(&plug
);
3140 ret
= btrfs_write_marked_extents(fs_info
, &log
->dirty_log_pages
, mark
);
3142 * -EAGAIN happens when someone, e.g., a concurrent transaction
3143 * commit, writes a dirty extent in this tree-log commit. This
3144 * concurrent write will create a hole writing out the extents,
3145 * and we cannot proceed on a zoned filesystem, requiring
3146 * sequential writing. While we can bail out to a full commit
3147 * here, but we can continue hoping the concurrent writing fills
3150 if (ret
== -EAGAIN
&& btrfs_is_zoned(fs_info
))
3153 blk_finish_plug(&plug
);
3154 btrfs_abort_transaction(trans
, ret
);
3155 btrfs_set_log_full_commit(trans
);
3156 mutex_unlock(&root
->log_mutex
);
3161 * We _must_ update under the root->log_mutex in order to make sure we
3162 * have a consistent view of the log root we are trying to commit at
3165 * We _must_ copy this into a local copy, because we are not holding the
3166 * log_root_tree->log_mutex yet. This is important because when we
3167 * commit the log_root_tree we must have a consistent view of the
3168 * log_root_tree when we update the super block to point at the
3169 * log_root_tree bytenr. If we update the log_root_tree here we'll race
3170 * with the commit and possibly point at the new block which we may not
3173 btrfs_set_root_node(&log
->root_item
, log
->node
);
3174 memcpy(&new_root_item
, &log
->root_item
, sizeof(new_root_item
));
3176 root
->log_transid
++;
3177 log
->log_transid
= root
->log_transid
;
3178 root
->log_start_pid
= 0;
3180 * IO has been started, blocks of the log tree have WRITTEN flag set
3181 * in their headers. new modifications of the log will be written to
3182 * new positions. so it's safe to allow log writers to go in.
3184 mutex_unlock(&root
->log_mutex
);
3186 if (btrfs_is_zoned(fs_info
)) {
3187 mutex_lock(&fs_info
->tree_root
->log_mutex
);
3188 if (!log_root_tree
->node
) {
3189 ret
= btrfs_alloc_log_tree_node(trans
, log_root_tree
);
3191 mutex_unlock(&fs_info
->tree_root
->log_mutex
);
3192 blk_finish_plug(&plug
);
3196 mutex_unlock(&fs_info
->tree_root
->log_mutex
);
3199 btrfs_init_log_ctx(&root_log_ctx
, NULL
);
3201 mutex_lock(&log_root_tree
->log_mutex
);
3203 index2
= log_root_tree
->log_transid
% 2;
3204 list_add_tail(&root_log_ctx
.list
, &log_root_tree
->log_ctxs
[index2
]);
3205 root_log_ctx
.log_transid
= log_root_tree
->log_transid
;
3208 * Now we are safe to update the log_root_tree because we're under the
3209 * log_mutex, and we're a current writer so we're holding the commit
3210 * open until we drop the log_mutex.
3212 ret
= update_log_root(trans
, log
, &new_root_item
);
3214 if (!list_empty(&root_log_ctx
.list
))
3215 list_del_init(&root_log_ctx
.list
);
3217 blk_finish_plug(&plug
);
3218 btrfs_set_log_full_commit(trans
);
3220 if (ret
!= -ENOSPC
) {
3221 btrfs_abort_transaction(trans
, ret
);
3222 mutex_unlock(&log_root_tree
->log_mutex
);
3225 btrfs_wait_tree_log_extents(log
, mark
);
3226 mutex_unlock(&log_root_tree
->log_mutex
);
3227 ret
= BTRFS_LOG_FORCE_COMMIT
;
3231 if (log_root_tree
->log_transid_committed
>= root_log_ctx
.log_transid
) {
3232 blk_finish_plug(&plug
);
3233 list_del_init(&root_log_ctx
.list
);
3234 mutex_unlock(&log_root_tree
->log_mutex
);
3235 ret
= root_log_ctx
.log_ret
;
3239 index2
= root_log_ctx
.log_transid
% 2;
3240 if (atomic_read(&log_root_tree
->log_commit
[index2
])) {
3241 blk_finish_plug(&plug
);
3242 ret
= btrfs_wait_tree_log_extents(log
, mark
);
3243 wait_log_commit(log_root_tree
,
3244 root_log_ctx
.log_transid
);
3245 mutex_unlock(&log_root_tree
->log_mutex
);
3247 ret
= root_log_ctx
.log_ret
;
3250 ASSERT(root_log_ctx
.log_transid
== log_root_tree
->log_transid
);
3251 atomic_set(&log_root_tree
->log_commit
[index2
], 1);
3253 if (atomic_read(&log_root_tree
->log_commit
[(index2
+ 1) % 2])) {
3254 wait_log_commit(log_root_tree
,
3255 root_log_ctx
.log_transid
- 1);
3259 * now that we've moved on to the tree of log tree roots,
3260 * check the full commit flag again
3262 if (btrfs_need_log_full_commit(trans
)) {
3263 blk_finish_plug(&plug
);
3264 btrfs_wait_tree_log_extents(log
, mark
);
3265 mutex_unlock(&log_root_tree
->log_mutex
);
3266 ret
= BTRFS_LOG_FORCE_COMMIT
;
3267 goto out_wake_log_root
;
3270 ret
= btrfs_write_marked_extents(fs_info
,
3271 &log_root_tree
->dirty_log_pages
,
3272 EXTENT_DIRTY
| EXTENT_NEW
);
3273 blk_finish_plug(&plug
);
3275 * As described above, -EAGAIN indicates a hole in the extents. We
3276 * cannot wait for these write outs since the waiting cause a
3277 * deadlock. Bail out to the full commit instead.
3279 if (ret
== -EAGAIN
&& btrfs_is_zoned(fs_info
)) {
3280 btrfs_set_log_full_commit(trans
);
3281 btrfs_wait_tree_log_extents(log
, mark
);
3282 mutex_unlock(&log_root_tree
->log_mutex
);
3283 goto out_wake_log_root
;
3285 btrfs_set_log_full_commit(trans
);
3286 btrfs_abort_transaction(trans
, ret
);
3287 mutex_unlock(&log_root_tree
->log_mutex
);
3288 goto out_wake_log_root
;
3290 ret
= btrfs_wait_tree_log_extents(log
, mark
);
3292 ret
= btrfs_wait_tree_log_extents(log_root_tree
,
3293 EXTENT_NEW
| EXTENT_DIRTY
);
3295 btrfs_set_log_full_commit(trans
);
3296 mutex_unlock(&log_root_tree
->log_mutex
);
3297 goto out_wake_log_root
;
3300 log_root_start
= log_root_tree
->node
->start
;
3301 log_root_level
= btrfs_header_level(log_root_tree
->node
);
3302 log_root_tree
->log_transid
++;
3303 mutex_unlock(&log_root_tree
->log_mutex
);
3306 * Here we are guaranteed that nobody is going to write the superblock
3307 * for the current transaction before us and that neither we do write
3308 * our superblock before the previous transaction finishes its commit
3309 * and writes its superblock, because:
3311 * 1) We are holding a handle on the current transaction, so no body
3312 * can commit it until we release the handle;
3314 * 2) Before writing our superblock we acquire the tree_log_mutex, so
3315 * if the previous transaction is still committing, and hasn't yet
3316 * written its superblock, we wait for it to do it, because a
3317 * transaction commit acquires the tree_log_mutex when the commit
3318 * begins and releases it only after writing its superblock.
3320 mutex_lock(&fs_info
->tree_log_mutex
);
3323 * The previous transaction writeout phase could have failed, and thus
3324 * marked the fs in an error state. We must not commit here, as we
3325 * could have updated our generation in the super_for_commit and
3326 * writing the super here would result in transid mismatches. If there
3327 * is an error here just bail.
3329 if (BTRFS_FS_ERROR(fs_info
)) {
3331 btrfs_set_log_full_commit(trans
);
3332 btrfs_abort_transaction(trans
, ret
);
3333 mutex_unlock(&fs_info
->tree_log_mutex
);
3334 goto out_wake_log_root
;
3337 btrfs_set_super_log_root(fs_info
->super_for_commit
, log_root_start
);
3338 btrfs_set_super_log_root_level(fs_info
->super_for_commit
, log_root_level
);
3339 ret
= write_all_supers(fs_info
, 1);
3340 mutex_unlock(&fs_info
->tree_log_mutex
);
3342 btrfs_set_log_full_commit(trans
);
3343 btrfs_abort_transaction(trans
, ret
);
3344 goto out_wake_log_root
;
3348 * We know there can only be one task here, since we have not yet set
3349 * root->log_commit[index1] to 0 and any task attempting to sync the
3350 * log must wait for the previous log transaction to commit if it's
3351 * still in progress or wait for the current log transaction commit if
3352 * someone else already started it. We use <= and not < because the
3353 * first log transaction has an ID of 0.
3355 ASSERT(root
->last_log_commit
<= log_transid
);
3356 root
->last_log_commit
= log_transid
;
3359 mutex_lock(&log_root_tree
->log_mutex
);
3360 btrfs_remove_all_log_ctxs(log_root_tree
, index2
, ret
);
3362 log_root_tree
->log_transid_committed
++;
3363 atomic_set(&log_root_tree
->log_commit
[index2
], 0);
3364 mutex_unlock(&log_root_tree
->log_mutex
);
3367 * The barrier before waitqueue_active (in cond_wake_up) is needed so
3368 * all the updates above are seen by the woken threads. It might not be
3369 * necessary, but proving that seems to be hard.
3371 cond_wake_up(&log_root_tree
->log_commit_wait
[index2
]);
3373 mutex_lock(&root
->log_mutex
);
3374 btrfs_remove_all_log_ctxs(root
, index1
, ret
);
3375 root
->log_transid_committed
++;
3376 atomic_set(&root
->log_commit
[index1
], 0);
3377 mutex_unlock(&root
->log_mutex
);
3380 * The barrier before waitqueue_active (in cond_wake_up) is needed so
3381 * all the updates above are seen by the woken threads. It might not be
3382 * necessary, but proving that seems to be hard.
3384 cond_wake_up(&root
->log_commit_wait
[index1
]);
3388 static void free_log_tree(struct btrfs_trans_handle
*trans
,
3389 struct btrfs_root
*log
)
3392 struct walk_control wc
= {
3394 .process_func
= process_one_buffer
3398 ret
= walk_log_tree(trans
, log
, &wc
);
3401 * We weren't able to traverse the entire log tree, the
3402 * typical scenario is getting an -EIO when reading an
3403 * extent buffer of the tree, due to a previous writeback
3406 set_bit(BTRFS_FS_STATE_LOG_CLEANUP_ERROR
,
3407 &log
->fs_info
->fs_state
);
3410 * Some extent buffers of the log tree may still be dirty
3411 * and not yet written back to storage, because we may
3412 * have updates to a log tree without syncing a log tree,
3413 * such as during rename and link operations. So flush
3414 * them out and wait for their writeback to complete, so
3415 * that we properly cleanup their state and pages.
3417 btrfs_write_marked_extents(log
->fs_info
,
3418 &log
->dirty_log_pages
,
3419 EXTENT_DIRTY
| EXTENT_NEW
);
3420 btrfs_wait_tree_log_extents(log
,
3421 EXTENT_DIRTY
| EXTENT_NEW
);
3424 btrfs_abort_transaction(trans
, ret
);
3426 btrfs_handle_fs_error(log
->fs_info
, ret
, NULL
);
3430 clear_extent_bits(&log
->dirty_log_pages
, 0, (u64
)-1,
3431 EXTENT_DIRTY
| EXTENT_NEW
| EXTENT_NEED_WAIT
);
3432 extent_io_tree_release(&log
->log_csum_range
);
3434 btrfs_put_root(log
);
3438 * free all the extents used by the tree log. This should be called
3439 * at commit time of the full transaction
3441 int btrfs_free_log(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
)
3443 if (root
->log_root
) {
3444 free_log_tree(trans
, root
->log_root
);
3445 root
->log_root
= NULL
;
3446 clear_bit(BTRFS_ROOT_HAS_LOG_TREE
, &root
->state
);
3451 int btrfs_free_log_root_tree(struct btrfs_trans_handle
*trans
,
3452 struct btrfs_fs_info
*fs_info
)
3454 if (fs_info
->log_root_tree
) {
3455 free_log_tree(trans
, fs_info
->log_root_tree
);
3456 fs_info
->log_root_tree
= NULL
;
3457 clear_bit(BTRFS_ROOT_HAS_LOG_TREE
, &fs_info
->tree_root
->state
);
3463 * Check if an inode was logged in the current transaction. This correctly deals
3464 * with the case where the inode was logged but has a logged_trans of 0, which
3465 * happens if the inode is evicted and loaded again, as logged_trans is an in
3466 * memory only field (not persisted).
3468 * Returns 1 if the inode was logged before in the transaction, 0 if it was not,
3471 static int inode_logged(struct btrfs_trans_handle
*trans
,
3472 struct btrfs_inode
*inode
,
3473 struct btrfs_path
*path_in
)
3475 struct btrfs_path
*path
= path_in
;
3476 struct btrfs_key key
;
3479 if (inode
->logged_trans
== trans
->transid
)
3483 * If logged_trans is not 0, then we know the inode logged was not logged
3484 * in this transaction, so we can return false right away.
3486 if (inode
->logged_trans
> 0)
3490 * If no log tree was created for this root in this transaction, then
3491 * the inode can not have been logged in this transaction. In that case
3492 * set logged_trans to anything greater than 0 and less than the current
3493 * transaction's ID, to avoid the search below in a future call in case
3494 * a log tree gets created after this.
3496 if (!test_bit(BTRFS_ROOT_HAS_LOG_TREE
, &inode
->root
->state
)) {
3497 inode
->logged_trans
= trans
->transid
- 1;
3502 * We have a log tree and the inode's logged_trans is 0. We can't tell
3503 * for sure if the inode was logged before in this transaction by looking
3504 * only at logged_trans. We could be pessimistic and assume it was, but
3505 * that can lead to unnecessarily logging an inode during rename and link
3506 * operations, and then further updating the log in followup rename and
3507 * link operations, specially if it's a directory, which adds latency
3508 * visible to applications doing a series of rename or link operations.
3510 * A logged_trans of 0 here can mean several things:
3512 * 1) The inode was never logged since the filesystem was mounted, and may
3513 * or may have not been evicted and loaded again;
3515 * 2) The inode was logged in a previous transaction, then evicted and
3516 * then loaded again;
3518 * 3) The inode was logged in the current transaction, then evicted and
3519 * then loaded again.
3521 * For cases 1) and 2) we don't want to return true, but we need to detect
3522 * case 3) and return true. So we do a search in the log root for the inode
3525 key
.objectid
= btrfs_ino(inode
);
3526 key
.type
= BTRFS_INODE_ITEM_KEY
;
3530 path
= btrfs_alloc_path();
3535 ret
= btrfs_search_slot(NULL
, inode
->root
->log_root
, &key
, path
, 0, 0);
3538 btrfs_release_path(path
);
3540 btrfs_free_path(path
);
3543 * Logging an inode always results in logging its inode item. So if we
3544 * did not find the item we know the inode was not logged for sure.
3548 } else if (ret
> 0) {
3550 * Set logged_trans to a value greater than 0 and less then the
3551 * current transaction to avoid doing the search in future calls.
3553 inode
->logged_trans
= trans
->transid
- 1;
3558 * The inode was previously logged and then evicted, set logged_trans to
3559 * the current transacion's ID, to avoid future tree searches as long as
3560 * the inode is not evicted again.
3562 inode
->logged_trans
= trans
->transid
;
3565 * If it's a directory, then we must set last_dir_index_offset to the
3566 * maximum possible value, so that the next attempt to log the inode does
3567 * not skip checking if dir index keys found in modified subvolume tree
3568 * leaves have been logged before, otherwise it would result in attempts
3569 * to insert duplicate dir index keys in the log tree. This must be done
3570 * because last_dir_index_offset is an in-memory only field, not persisted
3571 * in the inode item or any other on-disk structure, so its value is lost
3572 * once the inode is evicted.
3574 if (S_ISDIR(inode
->vfs_inode
.i_mode
))
3575 inode
->last_dir_index_offset
= (u64
)-1;
3581 * Delete a directory entry from the log if it exists.
3583 * Returns < 0 on error
3584 * 1 if the entry does not exists
3585 * 0 if the entry existed and was successfully deleted
3587 static int del_logged_dentry(struct btrfs_trans_handle
*trans
,
3588 struct btrfs_root
*log
,
3589 struct btrfs_path
*path
,
3591 const char *name
, int name_len
,
3594 struct btrfs_dir_item
*di
;
3597 * We only log dir index items of a directory, so we don't need to look
3598 * for dir item keys.
3600 di
= btrfs_lookup_dir_index_item(trans
, log
, path
, dir_ino
,
3601 index
, name
, name_len
, -1);
3608 * We do not need to update the size field of the directory's
3609 * inode item because on log replay we update the field to reflect
3610 * all existing entries in the directory (see overwrite_item()).
3612 return btrfs_delete_one_dir_name(trans
, log
, path
, di
);
3616 * If both a file and directory are logged, and unlinks or renames are
3617 * mixed in, we have a few interesting corners:
3619 * create file X in dir Y
3620 * link file X to X.link in dir Y
3622 * unlink file X but leave X.link
3625 * After a crash we would expect only X.link to exist. But file X
3626 * didn't get fsync'd again so the log has back refs for X and X.link.
3628 * We solve this by removing directory entries and inode backrefs from the
3629 * log when a file that was logged in the current transaction is
3630 * unlinked. Any later fsync will include the updated log entries, and
3631 * we'll be able to reconstruct the proper directory items from backrefs.
3633 * This optimizations allows us to avoid relogging the entire inode
3634 * or the entire directory.
3636 void btrfs_del_dir_entries_in_log(struct btrfs_trans_handle
*trans
,
3637 struct btrfs_root
*root
,
3638 const char *name
, int name_len
,
3639 struct btrfs_inode
*dir
, u64 index
)
3641 struct btrfs_path
*path
;
3644 ret
= inode_logged(trans
, dir
, NULL
);
3648 btrfs_set_log_full_commit(trans
);
3652 ret
= join_running_log_trans(root
);
3656 mutex_lock(&dir
->log_mutex
);
3658 path
= btrfs_alloc_path();
3664 ret
= del_logged_dentry(trans
, root
->log_root
, path
, btrfs_ino(dir
),
3665 name
, name_len
, index
);
3666 btrfs_free_path(path
);
3668 mutex_unlock(&dir
->log_mutex
);
3670 btrfs_set_log_full_commit(trans
);
3671 btrfs_end_log_trans(root
);
3674 /* see comments for btrfs_del_dir_entries_in_log */
3675 void btrfs_del_inode_ref_in_log(struct btrfs_trans_handle
*trans
,
3676 struct btrfs_root
*root
,
3677 const char *name
, int name_len
,
3678 struct btrfs_inode
*inode
, u64 dirid
)
3680 struct btrfs_root
*log
;
3684 ret
= inode_logged(trans
, inode
, NULL
);
3688 btrfs_set_log_full_commit(trans
);
3692 ret
= join_running_log_trans(root
);
3695 log
= root
->log_root
;
3696 mutex_lock(&inode
->log_mutex
);
3698 ret
= btrfs_del_inode_ref(trans
, log
, name
, name_len
, btrfs_ino(inode
),
3700 mutex_unlock(&inode
->log_mutex
);
3701 if (ret
< 0 && ret
!= -ENOENT
)
3702 btrfs_set_log_full_commit(trans
);
3703 btrfs_end_log_trans(root
);
3707 * creates a range item in the log for 'dirid'. first_offset and
3708 * last_offset tell us which parts of the key space the log should
3709 * be considered authoritative for.
3711 static noinline
int insert_dir_log_key(struct btrfs_trans_handle
*trans
,
3712 struct btrfs_root
*log
,
3713 struct btrfs_path
*path
,
3715 u64 first_offset
, u64 last_offset
)
3718 struct btrfs_key key
;
3719 struct btrfs_dir_log_item
*item
;
3721 key
.objectid
= dirid
;
3722 key
.offset
= first_offset
;
3723 key
.type
= BTRFS_DIR_LOG_INDEX_KEY
;
3724 ret
= btrfs_insert_empty_item(trans
, log
, path
, &key
, sizeof(*item
));
3726 * -EEXIST is fine and can happen sporadically when we are logging a
3727 * directory and have concurrent insertions in the subvolume's tree for
3728 * items from other inodes and that result in pushing off some dir items
3729 * from one leaf to another in order to accommodate for the new items.
3730 * This results in logging the same dir index range key.
3732 if (ret
&& ret
!= -EEXIST
)
3735 item
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
3736 struct btrfs_dir_log_item
);
3737 if (ret
== -EEXIST
) {
3738 const u64 curr_end
= btrfs_dir_log_end(path
->nodes
[0], item
);
3741 * btrfs_del_dir_entries_in_log() might have been called during
3742 * an unlink between the initial insertion of this key and the
3743 * current update, or we might be logging a single entry deletion
3744 * during a rename, so set the new last_offset to the max value.
3746 last_offset
= max(last_offset
, curr_end
);
3748 btrfs_set_dir_log_end(path
->nodes
[0], item
, last_offset
);
3749 btrfs_mark_buffer_dirty(path
->nodes
[0]);
3750 btrfs_release_path(path
);
3754 static int flush_dir_items_batch(struct btrfs_trans_handle
*trans
,
3755 struct btrfs_root
*log
,
3756 struct extent_buffer
*src
,
3757 struct btrfs_path
*dst_path
,
3761 char *ins_data
= NULL
;
3762 struct btrfs_item_batch batch
;
3763 struct extent_buffer
*dst
;
3764 unsigned long src_offset
;
3765 unsigned long dst_offset
;
3766 struct btrfs_key key
;
3775 btrfs_item_key_to_cpu(src
, &key
, start_slot
);
3776 item_size
= btrfs_item_size(src
, start_slot
);
3778 batch
.data_sizes
= &item_size
;
3779 batch
.total_data_size
= item_size
;
3781 struct btrfs_key
*ins_keys
;
3784 ins_data
= kmalloc(count
* sizeof(u32
) +
3785 count
* sizeof(struct btrfs_key
), GFP_NOFS
);
3789 ins_sizes
= (u32
*)ins_data
;
3790 ins_keys
= (struct btrfs_key
*)(ins_data
+ count
* sizeof(u32
));
3791 batch
.keys
= ins_keys
;
3792 batch
.data_sizes
= ins_sizes
;
3793 batch
.total_data_size
= 0;
3795 for (i
= 0; i
< count
; i
++) {
3796 const int slot
= start_slot
+ i
;
3798 btrfs_item_key_to_cpu(src
, &ins_keys
[i
], slot
);
3799 ins_sizes
[i
] = btrfs_item_size(src
, slot
);
3800 batch
.total_data_size
+= ins_sizes
[i
];
3804 ret
= btrfs_insert_empty_items(trans
, log
, dst_path
, &batch
);
3808 dst
= dst_path
->nodes
[0];
3810 * Copy all the items in bulk, in a single copy operation. Item data is
3811 * organized such that it's placed at the end of a leaf and from right
3812 * to left. For example, the data for the second item ends at an offset
3813 * that matches the offset where the data for the first item starts, the
3814 * data for the third item ends at an offset that matches the offset
3815 * where the data of the second items starts, and so on.
3816 * Therefore our source and destination start offsets for copy match the
3817 * offsets of the last items (highest slots).
3819 dst_offset
= btrfs_item_ptr_offset(dst
, dst_path
->slots
[0] + count
- 1);
3820 src_offset
= btrfs_item_ptr_offset(src
, start_slot
+ count
- 1);
3821 copy_extent_buffer(dst
, src
, dst_offset
, src_offset
, batch
.total_data_size
);
3822 btrfs_release_path(dst_path
);
3829 static int process_dir_items_leaf(struct btrfs_trans_handle
*trans
,
3830 struct btrfs_inode
*inode
,
3831 struct btrfs_path
*path
,
3832 struct btrfs_path
*dst_path
,
3833 struct btrfs_log_ctx
*ctx
,
3834 u64
*last_old_dentry_offset
)
3836 struct btrfs_root
*log
= inode
->root
->log_root
;
3837 struct extent_buffer
*src
= path
->nodes
[0];
3838 const int nritems
= btrfs_header_nritems(src
);
3839 const u64 ino
= btrfs_ino(inode
);
3840 bool last_found
= false;
3841 int batch_start
= 0;
3845 for (i
= path
->slots
[0]; i
< nritems
; i
++) {
3846 struct btrfs_dir_item
*di
;
3847 struct btrfs_key key
;
3850 btrfs_item_key_to_cpu(src
, &key
, i
);
3852 if (key
.objectid
!= ino
|| key
.type
!= BTRFS_DIR_INDEX_KEY
) {
3857 di
= btrfs_item_ptr(src
, i
, struct btrfs_dir_item
);
3858 ctx
->last_dir_item_offset
= key
.offset
;
3861 * Skip ranges of items that consist only of dir item keys created
3862 * in past transactions. However if we find a gap, we must log a
3863 * dir index range item for that gap, so that index keys in that
3864 * gap are deleted during log replay.
3866 if (btrfs_dir_transid(src
, di
) < trans
->transid
) {
3867 if (key
.offset
> *last_old_dentry_offset
+ 1) {
3868 ret
= insert_dir_log_key(trans
, log
, dst_path
,
3869 ino
, *last_old_dentry_offset
+ 1,
3875 *last_old_dentry_offset
= key
.offset
;
3879 * We must make sure that when we log a directory entry, the
3880 * corresponding inode, after log replay, has a matching link
3881 * count. For example:
3887 * xfs_io -c "fsync" mydir
3889 * <mount fs and log replay>
3891 * Would result in a fsync log that when replayed, our file inode
3892 * would have a link count of 1, but we get two directory entries
3893 * pointing to the same inode. After removing one of the names,
3894 * it would not be possible to remove the other name, which
3895 * resulted always in stale file handle errors, and would not be
3896 * possible to rmdir the parent directory, since its i_size could
3897 * never be decremented to the value BTRFS_EMPTY_DIR_SIZE,
3898 * resulting in -ENOTEMPTY errors.
3900 if (!ctx
->log_new_dentries
) {
3901 struct btrfs_key di_key
;
3903 btrfs_dir_item_key_to_cpu(src
, di
, &di_key
);
3904 if (di_key
.type
!= BTRFS_ROOT_ITEM_KEY
)
3905 ctx
->log_new_dentries
= true;
3908 if (!ctx
->logged_before
)
3912 * If we were logged before and have logged dir items, we can skip
3913 * checking if any item with a key offset larger than the last one
3914 * we logged is in the log tree, saving time and avoiding adding
3915 * contention on the log tree. We can only rely on the value of
3916 * last_dir_index_offset when we know for sure that the inode was
3917 * previously logged in the current transaction.
3919 if (key
.offset
> inode
->last_dir_index_offset
)
3922 * Check if the key was already logged before. If not we can add
3923 * it to a batch for bulk insertion.
3925 ret
= btrfs_search_slot(NULL
, log
, &key
, dst_path
, 0, 0);
3928 } else if (ret
> 0) {
3929 btrfs_release_path(dst_path
);
3934 * Item exists in the log. Overwrite the item in the log if it
3935 * has different content or do nothing if it has exactly the same
3936 * content. And then flush the current batch if any - do it after
3937 * overwriting the current item, or we would deadlock otherwise,
3938 * since we are holding a path for the existing item.
3940 ret
= do_overwrite_item(trans
, log
, dst_path
, src
, i
, &key
);
3944 if (batch_size
> 0) {
3945 ret
= flush_dir_items_batch(trans
, log
, src
, dst_path
,
3946 batch_start
, batch_size
);
3953 if (batch_size
== 0)
3958 if (batch_size
> 0) {
3961 ret
= flush_dir_items_batch(trans
, log
, src
, dst_path
,
3962 batch_start
, batch_size
);
3967 return last_found
? 1 : 0;
3971 * log all the items included in the current transaction for a given
3972 * directory. This also creates the range items in the log tree required
3973 * to replay anything deleted before the fsync
3975 static noinline
int log_dir_items(struct btrfs_trans_handle
*trans
,
3976 struct btrfs_inode
*inode
,
3977 struct btrfs_path
*path
,
3978 struct btrfs_path
*dst_path
,
3979 struct btrfs_log_ctx
*ctx
,
3980 u64 min_offset
, u64
*last_offset_ret
)
3982 struct btrfs_key min_key
;
3983 struct btrfs_root
*root
= inode
->root
;
3984 struct btrfs_root
*log
= root
->log_root
;
3987 u64 last_old_dentry_offset
= min_offset
- 1;
3988 u64 last_offset
= (u64
)-1;
3989 u64 ino
= btrfs_ino(inode
);
3991 min_key
.objectid
= ino
;
3992 min_key
.type
= BTRFS_DIR_INDEX_KEY
;
3993 min_key
.offset
= min_offset
;
3995 ret
= btrfs_search_forward(root
, &min_key
, path
, trans
->transid
);
3998 * we didn't find anything from this transaction, see if there
3999 * is anything at all
4001 if (ret
!= 0 || min_key
.objectid
!= ino
||
4002 min_key
.type
!= BTRFS_DIR_INDEX_KEY
) {
4003 min_key
.objectid
= ino
;
4004 min_key
.type
= BTRFS_DIR_INDEX_KEY
;
4005 min_key
.offset
= (u64
)-1;
4006 btrfs_release_path(path
);
4007 ret
= btrfs_search_slot(NULL
, root
, &min_key
, path
, 0, 0);
4009 btrfs_release_path(path
);
4012 ret
= btrfs_previous_item(root
, path
, ino
, BTRFS_DIR_INDEX_KEY
);
4014 /* if ret == 0 there are items for this type,
4015 * create a range to tell us the last key of this type.
4016 * otherwise, there are no items in this directory after
4017 * *min_offset, and we create a range to indicate that.
4020 struct btrfs_key tmp
;
4022 btrfs_item_key_to_cpu(path
->nodes
[0], &tmp
,
4024 if (tmp
.type
== BTRFS_DIR_INDEX_KEY
)
4025 last_old_dentry_offset
= tmp
.offset
;
4030 /* go backward to find any previous key */
4031 ret
= btrfs_previous_item(root
, path
, ino
, BTRFS_DIR_INDEX_KEY
);
4033 struct btrfs_key tmp
;
4035 btrfs_item_key_to_cpu(path
->nodes
[0], &tmp
, path
->slots
[0]);
4037 * The dir index key before the first one we found that needs to
4038 * be logged might be in a previous leaf, and there might be a
4039 * gap between these keys, meaning that we had deletions that
4040 * happened. So the key range item we log (key type
4041 * BTRFS_DIR_LOG_INDEX_KEY) must cover a range that starts at the
4042 * previous key's offset plus 1, so that those deletes are replayed.
4044 if (tmp
.type
== BTRFS_DIR_INDEX_KEY
)
4045 last_old_dentry_offset
= tmp
.offset
;
4047 btrfs_release_path(path
);
4050 * Find the first key from this transaction again. See the note for
4051 * log_new_dir_dentries, if we're logging a directory recursively we
4052 * won't be holding its i_mutex, which means we can modify the directory
4053 * while we're logging it. If we remove an entry between our first
4054 * search and this search we'll not find the key again and can just
4058 ret
= btrfs_search_slot(NULL
, root
, &min_key
, path
, 0, 0);
4063 * we have a block from this transaction, log every item in it
4064 * from our directory
4067 ret
= process_dir_items_leaf(trans
, inode
, path
, dst_path
, ctx
,
4068 &last_old_dentry_offset
);
4074 path
->slots
[0] = btrfs_header_nritems(path
->nodes
[0]);
4077 * look ahead to the next item and see if it is also
4078 * from this directory and from this transaction
4080 ret
= btrfs_next_leaf(root
, path
);
4083 last_offset
= (u64
)-1;
4088 btrfs_item_key_to_cpu(path
->nodes
[0], &min_key
, path
->slots
[0]);
4089 if (min_key
.objectid
!= ino
|| min_key
.type
!= BTRFS_DIR_INDEX_KEY
) {
4090 last_offset
= (u64
)-1;
4093 if (btrfs_header_generation(path
->nodes
[0]) != trans
->transid
) {
4095 * The next leaf was not changed in the current transaction
4096 * and has at least one dir index key.
4097 * We check for the next key because there might have been
4098 * one or more deletions between the last key we logged and
4099 * that next key. So the key range item we log (key type
4100 * BTRFS_DIR_LOG_INDEX_KEY) must end at the next key's
4101 * offset minus 1, so that those deletes are replayed.
4103 last_offset
= min_key
.offset
- 1;
4106 if (need_resched()) {
4107 btrfs_release_path(path
);
4113 btrfs_release_path(path
);
4114 btrfs_release_path(dst_path
);
4117 *last_offset_ret
= last_offset
;
4119 * In case the leaf was changed in the current transaction but
4120 * all its dir items are from a past transaction, the last item
4121 * in the leaf is a dir item and there's no gap between that last
4122 * dir item and the first one on the next leaf (which did not
4123 * change in the current transaction), then we don't need to log
4124 * a range, last_old_dentry_offset is == to last_offset.
4126 ASSERT(last_old_dentry_offset
<= last_offset
);
4127 if (last_old_dentry_offset
< last_offset
) {
4128 ret
= insert_dir_log_key(trans
, log
, path
, ino
,
4129 last_old_dentry_offset
+ 1,
4139 * logging directories is very similar to logging inodes, We find all the items
4140 * from the current transaction and write them to the log.
4142 * The recovery code scans the directory in the subvolume, and if it finds a
4143 * key in the range logged that is not present in the log tree, then it means
4144 * that dir entry was unlinked during the transaction.
4146 * In order for that scan to work, we must include one key smaller than
4147 * the smallest logged by this transaction and one key larger than the largest
4148 * key logged by this transaction.
4150 static noinline
int log_directory_changes(struct btrfs_trans_handle
*trans
,
4151 struct btrfs_inode
*inode
,
4152 struct btrfs_path
*path
,
4153 struct btrfs_path
*dst_path
,
4154 struct btrfs_log_ctx
*ctx
)
4160 min_key
= BTRFS_DIR_START_INDEX
;
4162 ctx
->last_dir_item_offset
= inode
->last_dir_index_offset
;
4165 ret
= log_dir_items(trans
, inode
, path
, dst_path
,
4166 ctx
, min_key
, &max_key
);
4169 if (max_key
== (u64
)-1)
4171 min_key
= max_key
+ 1;
4174 inode
->last_dir_index_offset
= ctx
->last_dir_item_offset
;
4180 * a helper function to drop items from the log before we relog an
4181 * inode. max_key_type indicates the highest item type to remove.
4182 * This cannot be run for file data extents because it does not
4183 * free the extents they point to.
4185 static int drop_inode_items(struct btrfs_trans_handle
*trans
,
4186 struct btrfs_root
*log
,
4187 struct btrfs_path
*path
,
4188 struct btrfs_inode
*inode
,
4192 struct btrfs_key key
;
4193 struct btrfs_key found_key
;
4196 key
.objectid
= btrfs_ino(inode
);
4197 key
.type
= max_key_type
;
4198 key
.offset
= (u64
)-1;
4201 ret
= btrfs_search_slot(trans
, log
, &key
, path
, -1, 1);
4202 BUG_ON(ret
== 0); /* Logic error */
4206 if (path
->slots
[0] == 0)
4210 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
,
4213 if (found_key
.objectid
!= key
.objectid
)
4216 found_key
.offset
= 0;
4218 ret
= btrfs_bin_search(path
->nodes
[0], &found_key
, &start_slot
);
4222 ret
= btrfs_del_items(trans
, log
, path
, start_slot
,
4223 path
->slots
[0] - start_slot
+ 1);
4225 * If start slot isn't 0 then we don't need to re-search, we've
4226 * found the last guy with the objectid in this tree.
4228 if (ret
|| start_slot
!= 0)
4230 btrfs_release_path(path
);
4232 btrfs_release_path(path
);
4238 static int truncate_inode_items(struct btrfs_trans_handle
*trans
,
4239 struct btrfs_root
*log_root
,
4240 struct btrfs_inode
*inode
,
4241 u64 new_size
, u32 min_type
)
4243 struct btrfs_truncate_control control
= {
4244 .new_size
= new_size
,
4245 .ino
= btrfs_ino(inode
),
4246 .min_type
= min_type
,
4247 .skip_ref_updates
= true,
4250 return btrfs_truncate_inode_items(trans
, log_root
, &control
);
4253 static void fill_inode_item(struct btrfs_trans_handle
*trans
,
4254 struct extent_buffer
*leaf
,
4255 struct btrfs_inode_item
*item
,
4256 struct inode
*inode
, int log_inode_only
,
4259 struct btrfs_map_token token
;
4262 btrfs_init_map_token(&token
, leaf
);
4264 if (log_inode_only
) {
4265 /* set the generation to zero so the recover code
4266 * can tell the difference between an logging
4267 * just to say 'this inode exists' and a logging
4268 * to say 'update this inode with these values'
4270 btrfs_set_token_inode_generation(&token
, item
, 0);
4271 btrfs_set_token_inode_size(&token
, item
, logged_isize
);
4273 btrfs_set_token_inode_generation(&token
, item
,
4274 BTRFS_I(inode
)->generation
);
4275 btrfs_set_token_inode_size(&token
, item
, inode
->i_size
);
4278 btrfs_set_token_inode_uid(&token
, item
, i_uid_read(inode
));
4279 btrfs_set_token_inode_gid(&token
, item
, i_gid_read(inode
));
4280 btrfs_set_token_inode_mode(&token
, item
, inode
->i_mode
);
4281 btrfs_set_token_inode_nlink(&token
, item
, inode
->i_nlink
);
4283 btrfs_set_token_timespec_sec(&token
, &item
->atime
,
4284 inode
->i_atime
.tv_sec
);
4285 btrfs_set_token_timespec_nsec(&token
, &item
->atime
,
4286 inode
->i_atime
.tv_nsec
);
4288 btrfs_set_token_timespec_sec(&token
, &item
->mtime
,
4289 inode
->i_mtime
.tv_sec
);
4290 btrfs_set_token_timespec_nsec(&token
, &item
->mtime
,
4291 inode
->i_mtime
.tv_nsec
);
4293 btrfs_set_token_timespec_sec(&token
, &item
->ctime
,
4294 inode
->i_ctime
.tv_sec
);
4295 btrfs_set_token_timespec_nsec(&token
, &item
->ctime
,
4296 inode
->i_ctime
.tv_nsec
);
4299 * We do not need to set the nbytes field, in fact during a fast fsync
4300 * its value may not even be correct, since a fast fsync does not wait
4301 * for ordered extent completion, which is where we update nbytes, it
4302 * only waits for writeback to complete. During log replay as we find
4303 * file extent items and replay them, we adjust the nbytes field of the
4304 * inode item in subvolume tree as needed (see overwrite_item()).
4307 btrfs_set_token_inode_sequence(&token
, item
, inode_peek_iversion(inode
));
4308 btrfs_set_token_inode_transid(&token
, item
, trans
->transid
);
4309 btrfs_set_token_inode_rdev(&token
, item
, inode
->i_rdev
);
4310 flags
= btrfs_inode_combine_flags(BTRFS_I(inode
)->flags
,
4311 BTRFS_I(inode
)->ro_flags
);
4312 btrfs_set_token_inode_flags(&token
, item
, flags
);
4313 btrfs_set_token_inode_block_group(&token
, item
, 0);
4316 static int log_inode_item(struct btrfs_trans_handle
*trans
,
4317 struct btrfs_root
*log
, struct btrfs_path
*path
,
4318 struct btrfs_inode
*inode
, bool inode_item_dropped
)
4320 struct btrfs_inode_item
*inode_item
;
4324 * If we are doing a fast fsync and the inode was logged before in the
4325 * current transaction, then we know the inode was previously logged and
4326 * it exists in the log tree. For performance reasons, in this case use
4327 * btrfs_search_slot() directly with ins_len set to 0 so that we never
4328 * attempt a write lock on the leaf's parent, which adds unnecessary lock
4329 * contention in case there are concurrent fsyncs for other inodes of the
4330 * same subvolume. Using btrfs_insert_empty_item() when the inode item
4331 * already exists can also result in unnecessarily splitting a leaf.
4333 if (!inode_item_dropped
&& inode
->logged_trans
== trans
->transid
) {
4334 ret
= btrfs_search_slot(trans
, log
, &inode
->location
, path
, 0, 1);
4340 * This means it is the first fsync in the current transaction,
4341 * so the inode item is not in the log and we need to insert it.
4342 * We can never get -EEXIST because we are only called for a fast
4343 * fsync and in case an inode eviction happens after the inode was
4344 * logged before in the current transaction, when we load again
4345 * the inode, we set BTRFS_INODE_NEEDS_FULL_SYNC on its runtime
4346 * flags and set ->logged_trans to 0.
4348 ret
= btrfs_insert_empty_item(trans
, log
, path
, &inode
->location
,
4349 sizeof(*inode_item
));
4350 ASSERT(ret
!= -EEXIST
);
4354 inode_item
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
4355 struct btrfs_inode_item
);
4356 fill_inode_item(trans
, path
->nodes
[0], inode_item
, &inode
->vfs_inode
,
4358 btrfs_release_path(path
);
4362 static int log_csums(struct btrfs_trans_handle
*trans
,
4363 struct btrfs_inode
*inode
,
4364 struct btrfs_root
*log_root
,
4365 struct btrfs_ordered_sum
*sums
)
4367 const u64 lock_end
= sums
->bytenr
+ sums
->len
- 1;
4368 struct extent_state
*cached_state
= NULL
;
4372 * If this inode was not used for reflink operations in the current
4373 * transaction with new extents, then do the fast path, no need to
4374 * worry about logging checksum items with overlapping ranges.
4376 if (inode
->last_reflink_trans
< trans
->transid
)
4377 return btrfs_csum_file_blocks(trans
, log_root
, sums
);
4380 * Serialize logging for checksums. This is to avoid racing with the
4381 * same checksum being logged by another task that is logging another
4382 * file which happens to refer to the same extent as well. Such races
4383 * can leave checksum items in the log with overlapping ranges.
4385 ret
= lock_extent_bits(&log_root
->log_csum_range
, sums
->bytenr
,
4386 lock_end
, &cached_state
);
4390 * Due to extent cloning, we might have logged a csum item that covers a
4391 * subrange of a cloned extent, and later we can end up logging a csum
4392 * item for a larger subrange of the same extent or the entire range.
4393 * This would leave csum items in the log tree that cover the same range
4394 * and break the searches for checksums in the log tree, resulting in
4395 * some checksums missing in the fs/subvolume tree. So just delete (or
4396 * trim and adjust) any existing csum items in the log for this range.
4398 ret
= btrfs_del_csums(trans
, log_root
, sums
->bytenr
, sums
->len
);
4400 ret
= btrfs_csum_file_blocks(trans
, log_root
, sums
);
4402 unlock_extent_cached(&log_root
->log_csum_range
, sums
->bytenr
, lock_end
,
4408 static noinline
int copy_items(struct btrfs_trans_handle
*trans
,
4409 struct btrfs_inode
*inode
,
4410 struct btrfs_path
*dst_path
,
4411 struct btrfs_path
*src_path
,
4412 int start_slot
, int nr
, int inode_only
,
4415 struct btrfs_root
*log
= inode
->root
->log_root
;
4416 struct btrfs_file_extent_item
*extent
;
4417 struct extent_buffer
*src
= src_path
->nodes
[0];
4419 struct btrfs_key
*ins_keys
;
4421 struct btrfs_item_batch batch
;
4425 const bool skip_csum
= (inode
->flags
& BTRFS_INODE_NODATASUM
);
4426 const u64 i_size
= i_size_read(&inode
->vfs_inode
);
4428 ins_data
= kmalloc(nr
* sizeof(struct btrfs_key
) +
4429 nr
* sizeof(u32
), GFP_NOFS
);
4433 ins_sizes
= (u32
*)ins_data
;
4434 ins_keys
= (struct btrfs_key
*)(ins_data
+ nr
* sizeof(u32
));
4435 batch
.keys
= ins_keys
;
4436 batch
.data_sizes
= ins_sizes
;
4437 batch
.total_data_size
= 0;
4441 for (i
= 0; i
< nr
; i
++) {
4442 const int src_slot
= start_slot
+ i
;
4443 struct btrfs_root
*csum_root
;
4444 struct btrfs_ordered_sum
*sums
;
4445 struct btrfs_ordered_sum
*sums_next
;
4446 LIST_HEAD(ordered_sums
);
4450 u64 extent_num_bytes
;
4453 btrfs_item_key_to_cpu(src
, &ins_keys
[dst_index
], src_slot
);
4455 if (ins_keys
[dst_index
].type
!= BTRFS_EXTENT_DATA_KEY
)
4458 extent
= btrfs_item_ptr(src
, src_slot
,
4459 struct btrfs_file_extent_item
);
4461 is_old_extent
= (btrfs_file_extent_generation(src
, extent
) <
4465 * Don't copy extents from past generations. That would make us
4466 * log a lot more metadata for common cases like doing only a
4467 * few random writes into a file and then fsync it for the first
4468 * time or after the full sync flag is set on the inode. We can
4469 * get leaves full of extent items, most of which are from past
4470 * generations, so we can skip them - as long as the inode has
4471 * not been the target of a reflink operation in this transaction,
4472 * as in that case it might have had file extent items with old
4473 * generations copied into it. We also must always log prealloc
4474 * extents that start at or beyond eof, otherwise we would lose
4475 * them on log replay.
4477 if (is_old_extent
&&
4478 ins_keys
[dst_index
].offset
< i_size
&&
4479 inode
->last_reflink_trans
< trans
->transid
)
4485 /* Only regular extents have checksums. */
4486 if (btrfs_file_extent_type(src
, extent
) != BTRFS_FILE_EXTENT_REG
)
4490 * If it's an extent created in a past transaction, then its
4491 * checksums are already accessible from the committed csum tree,
4492 * no need to log them.
4497 disk_bytenr
= btrfs_file_extent_disk_bytenr(src
, extent
);
4498 /* If it's an explicit hole, there are no checksums. */
4499 if (disk_bytenr
== 0)
4502 disk_num_bytes
= btrfs_file_extent_disk_num_bytes(src
, extent
);
4504 if (btrfs_file_extent_compression(src
, extent
)) {
4506 extent_num_bytes
= disk_num_bytes
;
4508 extent_offset
= btrfs_file_extent_offset(src
, extent
);
4509 extent_num_bytes
= btrfs_file_extent_num_bytes(src
, extent
);
4512 csum_root
= btrfs_csum_root(trans
->fs_info
, disk_bytenr
);
4513 disk_bytenr
+= extent_offset
;
4514 ret
= btrfs_lookup_csums_range(csum_root
, disk_bytenr
,
4515 disk_bytenr
+ extent_num_bytes
- 1,
4520 list_for_each_entry_safe(sums
, sums_next
, &ordered_sums
, list
) {
4522 ret
= log_csums(trans
, inode
, log
, sums
);
4523 list_del(&sums
->list
);
4530 ins_sizes
[dst_index
] = btrfs_item_size(src
, src_slot
);
4531 batch
.total_data_size
+= ins_sizes
[dst_index
];
4537 * We have a leaf full of old extent items that don't need to be logged,
4538 * so we don't need to do anything.
4543 ret
= btrfs_insert_empty_items(trans
, log
, dst_path
, &batch
);
4548 for (i
= 0; i
< nr
; i
++) {
4549 const int src_slot
= start_slot
+ i
;
4550 const int dst_slot
= dst_path
->slots
[0] + dst_index
;
4551 struct btrfs_key key
;
4552 unsigned long src_offset
;
4553 unsigned long dst_offset
;
4556 * We're done, all the remaining items in the source leaf
4557 * correspond to old file extent items.
4559 if (dst_index
>= batch
.nr
)
4562 btrfs_item_key_to_cpu(src
, &key
, src_slot
);
4564 if (key
.type
!= BTRFS_EXTENT_DATA_KEY
)
4567 extent
= btrfs_item_ptr(src
, src_slot
,
4568 struct btrfs_file_extent_item
);
4570 /* See the comment in the previous loop, same logic. */
4571 if (btrfs_file_extent_generation(src
, extent
) < trans
->transid
&&
4572 key
.offset
< i_size
&&
4573 inode
->last_reflink_trans
< trans
->transid
)
4577 dst_offset
= btrfs_item_ptr_offset(dst_path
->nodes
[0], dst_slot
);
4578 src_offset
= btrfs_item_ptr_offset(src
, src_slot
);
4580 if (key
.type
== BTRFS_INODE_ITEM_KEY
) {
4581 struct btrfs_inode_item
*inode_item
;
4583 inode_item
= btrfs_item_ptr(dst_path
->nodes
[0], dst_slot
,
4584 struct btrfs_inode_item
);
4585 fill_inode_item(trans
, dst_path
->nodes
[0], inode_item
,
4587 inode_only
== LOG_INODE_EXISTS
,
4590 copy_extent_buffer(dst_path
->nodes
[0], src
, dst_offset
,
4591 src_offset
, ins_sizes
[dst_index
]);
4597 btrfs_mark_buffer_dirty(dst_path
->nodes
[0]);
4598 btrfs_release_path(dst_path
);
4605 static int extent_cmp(void *priv
, const struct list_head
*a
,
4606 const struct list_head
*b
)
4608 const struct extent_map
*em1
, *em2
;
4610 em1
= list_entry(a
, struct extent_map
, list
);
4611 em2
= list_entry(b
, struct extent_map
, list
);
4613 if (em1
->start
< em2
->start
)
4615 else if (em1
->start
> em2
->start
)
4620 static int log_extent_csums(struct btrfs_trans_handle
*trans
,
4621 struct btrfs_inode
*inode
,
4622 struct btrfs_root
*log_root
,
4623 const struct extent_map
*em
,
4624 struct btrfs_log_ctx
*ctx
)
4626 struct btrfs_ordered_extent
*ordered
;
4627 struct btrfs_root
*csum_root
;
4630 u64 mod_start
= em
->mod_start
;
4631 u64 mod_len
= em
->mod_len
;
4632 LIST_HEAD(ordered_sums
);
4635 if (inode
->flags
& BTRFS_INODE_NODATASUM
||
4636 test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
) ||
4637 em
->block_start
== EXTENT_MAP_HOLE
)
4640 list_for_each_entry(ordered
, &ctx
->ordered_extents
, log_list
) {
4641 const u64 ordered_end
= ordered
->file_offset
+ ordered
->num_bytes
;
4642 const u64 mod_end
= mod_start
+ mod_len
;
4643 struct btrfs_ordered_sum
*sums
;
4648 if (ordered_end
<= mod_start
)
4650 if (mod_end
<= ordered
->file_offset
)
4654 * We are going to copy all the csums on this ordered extent, so
4655 * go ahead and adjust mod_start and mod_len in case this ordered
4656 * extent has already been logged.
4658 if (ordered
->file_offset
> mod_start
) {
4659 if (ordered_end
>= mod_end
)
4660 mod_len
= ordered
->file_offset
- mod_start
;
4662 * If we have this case
4664 * |--------- logged extent ---------|
4665 * |----- ordered extent ----|
4667 * Just don't mess with mod_start and mod_len, we'll
4668 * just end up logging more csums than we need and it
4672 if (ordered_end
< mod_end
) {
4673 mod_len
= mod_end
- ordered_end
;
4674 mod_start
= ordered_end
;
4681 * To keep us from looping for the above case of an ordered
4682 * extent that falls inside of the logged extent.
4684 if (test_and_set_bit(BTRFS_ORDERED_LOGGED_CSUM
, &ordered
->flags
))
4687 list_for_each_entry(sums
, &ordered
->list
, list
) {
4688 ret
= log_csums(trans
, inode
, log_root
, sums
);
4694 /* We're done, found all csums in the ordered extents. */
4698 /* If we're compressed we have to save the entire range of csums. */
4699 if (em
->compress_type
) {
4701 csum_len
= max(em
->block_len
, em
->orig_block_len
);
4703 csum_offset
= mod_start
- em
->start
;
4707 /* block start is already adjusted for the file extent offset. */
4708 csum_root
= btrfs_csum_root(trans
->fs_info
, em
->block_start
);
4709 ret
= btrfs_lookup_csums_range(csum_root
,
4710 em
->block_start
+ csum_offset
,
4711 em
->block_start
+ csum_offset
+
4712 csum_len
- 1, &ordered_sums
, 0);
4716 while (!list_empty(&ordered_sums
)) {
4717 struct btrfs_ordered_sum
*sums
= list_entry(ordered_sums
.next
,
4718 struct btrfs_ordered_sum
,
4721 ret
= log_csums(trans
, inode
, log_root
, sums
);
4722 list_del(&sums
->list
);
4729 static int log_one_extent(struct btrfs_trans_handle
*trans
,
4730 struct btrfs_inode
*inode
,
4731 const struct extent_map
*em
,
4732 struct btrfs_path
*path
,
4733 struct btrfs_log_ctx
*ctx
)
4735 struct btrfs_drop_extents_args drop_args
= { 0 };
4736 struct btrfs_root
*log
= inode
->root
->log_root
;
4737 struct btrfs_file_extent_item fi
= { 0 };
4738 struct extent_buffer
*leaf
;
4739 struct btrfs_key key
;
4740 u64 extent_offset
= em
->start
- em
->orig_start
;
4744 btrfs_set_stack_file_extent_generation(&fi
, trans
->transid
);
4745 if (test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
))
4746 btrfs_set_stack_file_extent_type(&fi
, BTRFS_FILE_EXTENT_PREALLOC
);
4748 btrfs_set_stack_file_extent_type(&fi
, BTRFS_FILE_EXTENT_REG
);
4750 block_len
= max(em
->block_len
, em
->orig_block_len
);
4751 if (em
->compress_type
!= BTRFS_COMPRESS_NONE
) {
4752 btrfs_set_stack_file_extent_disk_bytenr(&fi
, em
->block_start
);
4753 btrfs_set_stack_file_extent_disk_num_bytes(&fi
, block_len
);
4754 } else if (em
->block_start
< EXTENT_MAP_LAST_BYTE
) {
4755 btrfs_set_stack_file_extent_disk_bytenr(&fi
, em
->block_start
-
4757 btrfs_set_stack_file_extent_disk_num_bytes(&fi
, block_len
);
4760 btrfs_set_stack_file_extent_offset(&fi
, extent_offset
);
4761 btrfs_set_stack_file_extent_num_bytes(&fi
, em
->len
);
4762 btrfs_set_stack_file_extent_ram_bytes(&fi
, em
->ram_bytes
);
4763 btrfs_set_stack_file_extent_compression(&fi
, em
->compress_type
);
4765 ret
= log_extent_csums(trans
, inode
, log
, em
, ctx
);
4770 * If this is the first time we are logging the inode in the current
4771 * transaction, we can avoid btrfs_drop_extents(), which is expensive
4772 * because it does a deletion search, which always acquires write locks
4773 * for extent buffers at levels 2, 1 and 0. This not only wastes time
4774 * but also adds significant contention in a log tree, since log trees
4775 * are small, with a root at level 2 or 3 at most, due to their short
4778 if (ctx
->logged_before
) {
4779 drop_args
.path
= path
;
4780 drop_args
.start
= em
->start
;
4781 drop_args
.end
= em
->start
+ em
->len
;
4782 drop_args
.replace_extent
= true;
4783 drop_args
.extent_item_size
= sizeof(fi
);
4784 ret
= btrfs_drop_extents(trans
, log
, inode
, &drop_args
);
4789 if (!drop_args
.extent_inserted
) {
4790 key
.objectid
= btrfs_ino(inode
);
4791 key
.type
= BTRFS_EXTENT_DATA_KEY
;
4792 key
.offset
= em
->start
;
4794 ret
= btrfs_insert_empty_item(trans
, log
, path
, &key
,
4799 leaf
= path
->nodes
[0];
4800 write_extent_buffer(leaf
, &fi
,
4801 btrfs_item_ptr_offset(leaf
, path
->slots
[0]),
4803 btrfs_mark_buffer_dirty(leaf
);
4805 btrfs_release_path(path
);
4811 * Log all prealloc extents beyond the inode's i_size to make sure we do not
4812 * lose them after doing a full/fast fsync and replaying the log. We scan the
4813 * subvolume's root instead of iterating the inode's extent map tree because
4814 * otherwise we can log incorrect extent items based on extent map conversion.
4815 * That can happen due to the fact that extent maps are merged when they
4816 * are not in the extent map tree's list of modified extents.
4818 static int btrfs_log_prealloc_extents(struct btrfs_trans_handle
*trans
,
4819 struct btrfs_inode
*inode
,
4820 struct btrfs_path
*path
)
4822 struct btrfs_root
*root
= inode
->root
;
4823 struct btrfs_key key
;
4824 const u64 i_size
= i_size_read(&inode
->vfs_inode
);
4825 const u64 ino
= btrfs_ino(inode
);
4826 struct btrfs_path
*dst_path
= NULL
;
4827 bool dropped_extents
= false;
4828 u64 truncate_offset
= i_size
;
4829 struct extent_buffer
*leaf
;
4835 if (!(inode
->flags
& BTRFS_INODE_PREALLOC
))
4839 key
.type
= BTRFS_EXTENT_DATA_KEY
;
4840 key
.offset
= i_size
;
4841 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
4846 * We must check if there is a prealloc extent that starts before the
4847 * i_size and crosses the i_size boundary. This is to ensure later we
4848 * truncate down to the end of that extent and not to the i_size, as
4849 * otherwise we end up losing part of the prealloc extent after a log
4850 * replay and with an implicit hole if there is another prealloc extent
4851 * that starts at an offset beyond i_size.
4853 ret
= btrfs_previous_item(root
, path
, ino
, BTRFS_EXTENT_DATA_KEY
);
4858 struct btrfs_file_extent_item
*ei
;
4860 leaf
= path
->nodes
[0];
4861 slot
= path
->slots
[0];
4862 ei
= btrfs_item_ptr(leaf
, slot
, struct btrfs_file_extent_item
);
4864 if (btrfs_file_extent_type(leaf
, ei
) ==
4865 BTRFS_FILE_EXTENT_PREALLOC
) {
4868 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
4869 extent_end
= key
.offset
+
4870 btrfs_file_extent_num_bytes(leaf
, ei
);
4872 if (extent_end
> i_size
)
4873 truncate_offset
= extent_end
;
4880 leaf
= path
->nodes
[0];
4881 slot
= path
->slots
[0];
4883 if (slot
>= btrfs_header_nritems(leaf
)) {
4885 ret
= copy_items(trans
, inode
, dst_path
, path
,
4886 start_slot
, ins_nr
, 1, 0);
4891 ret
= btrfs_next_leaf(root
, path
);
4901 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
4902 if (key
.objectid
> ino
)
4904 if (WARN_ON_ONCE(key
.objectid
< ino
) ||
4905 key
.type
< BTRFS_EXTENT_DATA_KEY
||
4906 key
.offset
< i_size
) {
4910 if (!dropped_extents
) {
4912 * Avoid logging extent items logged in past fsync calls
4913 * and leading to duplicate keys in the log tree.
4915 ret
= truncate_inode_items(trans
, root
->log_root
, inode
,
4917 BTRFS_EXTENT_DATA_KEY
);
4920 dropped_extents
= true;
4927 dst_path
= btrfs_alloc_path();
4935 ret
= copy_items(trans
, inode
, dst_path
, path
,
4936 start_slot
, ins_nr
, 1, 0);
4938 btrfs_release_path(path
);
4939 btrfs_free_path(dst_path
);
4943 static int btrfs_log_changed_extents(struct btrfs_trans_handle
*trans
,
4944 struct btrfs_inode
*inode
,
4945 struct btrfs_path
*path
,
4946 struct btrfs_log_ctx
*ctx
)
4948 struct btrfs_ordered_extent
*ordered
;
4949 struct btrfs_ordered_extent
*tmp
;
4950 struct extent_map
*em
, *n
;
4951 struct list_head extents
;
4952 struct extent_map_tree
*tree
= &inode
->extent_tree
;
4956 INIT_LIST_HEAD(&extents
);
4958 write_lock(&tree
->lock
);
4960 list_for_each_entry_safe(em
, n
, &tree
->modified_extents
, list
) {
4961 list_del_init(&em
->list
);
4963 * Just an arbitrary number, this can be really CPU intensive
4964 * once we start getting a lot of extents, and really once we
4965 * have a bunch of extents we just want to commit since it will
4968 if (++num
> 32768) {
4969 list_del_init(&tree
->modified_extents
);
4974 if (em
->generation
< trans
->transid
)
4977 /* We log prealloc extents beyond eof later. */
4978 if (test_bit(EXTENT_FLAG_PREALLOC
, &em
->flags
) &&
4979 em
->start
>= i_size_read(&inode
->vfs_inode
))
4982 /* Need a ref to keep it from getting evicted from cache */
4983 refcount_inc(&em
->refs
);
4984 set_bit(EXTENT_FLAG_LOGGING
, &em
->flags
);
4985 list_add_tail(&em
->list
, &extents
);
4989 list_sort(NULL
, &extents
, extent_cmp
);
4991 while (!list_empty(&extents
)) {
4992 em
= list_entry(extents
.next
, struct extent_map
, list
);
4994 list_del_init(&em
->list
);
4997 * If we had an error we just need to delete everybody from our
5001 clear_em_logging(tree
, em
);
5002 free_extent_map(em
);
5006 write_unlock(&tree
->lock
);
5008 ret
= log_one_extent(trans
, inode
, em
, path
, ctx
);
5009 write_lock(&tree
->lock
);
5010 clear_em_logging(tree
, em
);
5011 free_extent_map(em
);
5013 WARN_ON(!list_empty(&extents
));
5014 write_unlock(&tree
->lock
);
5017 ret
= btrfs_log_prealloc_extents(trans
, inode
, path
);
5022 * We have logged all extents successfully, now make sure the commit of
5023 * the current transaction waits for the ordered extents to complete
5024 * before it commits and wipes out the log trees, otherwise we would
5025 * lose data if an ordered extents completes after the transaction
5026 * commits and a power failure happens after the transaction commit.
5028 list_for_each_entry_safe(ordered
, tmp
, &ctx
->ordered_extents
, log_list
) {
5029 list_del_init(&ordered
->log_list
);
5030 set_bit(BTRFS_ORDERED_LOGGED
, &ordered
->flags
);
5032 if (!test_bit(BTRFS_ORDERED_COMPLETE
, &ordered
->flags
)) {
5033 spin_lock_irq(&inode
->ordered_tree
.lock
);
5034 if (!test_bit(BTRFS_ORDERED_COMPLETE
, &ordered
->flags
)) {
5035 set_bit(BTRFS_ORDERED_PENDING
, &ordered
->flags
);
5036 atomic_inc(&trans
->transaction
->pending_ordered
);
5038 spin_unlock_irq(&inode
->ordered_tree
.lock
);
5040 btrfs_put_ordered_extent(ordered
);
5046 static int logged_inode_size(struct btrfs_root
*log
, struct btrfs_inode
*inode
,
5047 struct btrfs_path
*path
, u64
*size_ret
)
5049 struct btrfs_key key
;
5052 key
.objectid
= btrfs_ino(inode
);
5053 key
.type
= BTRFS_INODE_ITEM_KEY
;
5056 ret
= btrfs_search_slot(NULL
, log
, &key
, path
, 0, 0);
5059 } else if (ret
> 0) {
5062 struct btrfs_inode_item
*item
;
5064 item
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
5065 struct btrfs_inode_item
);
5066 *size_ret
= btrfs_inode_size(path
->nodes
[0], item
);
5068 * If the in-memory inode's i_size is smaller then the inode
5069 * size stored in the btree, return the inode's i_size, so
5070 * that we get a correct inode size after replaying the log
5071 * when before a power failure we had a shrinking truncate
5072 * followed by addition of a new name (rename / new hard link).
5073 * Otherwise return the inode size from the btree, to avoid
5074 * data loss when replaying a log due to previously doing a
5075 * write that expands the inode's size and logging a new name
5076 * immediately after.
5078 if (*size_ret
> inode
->vfs_inode
.i_size
)
5079 *size_ret
= inode
->vfs_inode
.i_size
;
5082 btrfs_release_path(path
);
5087 * At the moment we always log all xattrs. This is to figure out at log replay
5088 * time which xattrs must have their deletion replayed. If a xattr is missing
5089 * in the log tree and exists in the fs/subvol tree, we delete it. This is
5090 * because if a xattr is deleted, the inode is fsynced and a power failure
5091 * happens, causing the log to be replayed the next time the fs is mounted,
5092 * we want the xattr to not exist anymore (same behaviour as other filesystems
5093 * with a journal, ext3/4, xfs, f2fs, etc).
5095 static int btrfs_log_all_xattrs(struct btrfs_trans_handle
*trans
,
5096 struct btrfs_inode
*inode
,
5097 struct btrfs_path
*path
,
5098 struct btrfs_path
*dst_path
)
5100 struct btrfs_root
*root
= inode
->root
;
5102 struct btrfs_key key
;
5103 const u64 ino
= btrfs_ino(inode
);
5106 bool found_xattrs
= false;
5108 if (test_bit(BTRFS_INODE_NO_XATTRS
, &inode
->runtime_flags
))
5112 key
.type
= BTRFS_XATTR_ITEM_KEY
;
5115 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
5120 int slot
= path
->slots
[0];
5121 struct extent_buffer
*leaf
= path
->nodes
[0];
5122 int nritems
= btrfs_header_nritems(leaf
);
5124 if (slot
>= nritems
) {
5126 ret
= copy_items(trans
, inode
, dst_path
, path
,
5127 start_slot
, ins_nr
, 1, 0);
5132 ret
= btrfs_next_leaf(root
, path
);
5140 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
5141 if (key
.objectid
!= ino
|| key
.type
!= BTRFS_XATTR_ITEM_KEY
)
5148 found_xattrs
= true;
5152 ret
= copy_items(trans
, inode
, dst_path
, path
,
5153 start_slot
, ins_nr
, 1, 0);
5159 set_bit(BTRFS_INODE_NO_XATTRS
, &inode
->runtime_flags
);
5165 * When using the NO_HOLES feature if we punched a hole that causes the
5166 * deletion of entire leafs or all the extent items of the first leaf (the one
5167 * that contains the inode item and references) we may end up not processing
5168 * any extents, because there are no leafs with a generation matching the
5169 * current transaction that have extent items for our inode. So we need to find
5170 * if any holes exist and then log them. We also need to log holes after any
5171 * truncate operation that changes the inode's size.
5173 static int btrfs_log_holes(struct btrfs_trans_handle
*trans
,
5174 struct btrfs_inode
*inode
,
5175 struct btrfs_path
*path
)
5177 struct btrfs_root
*root
= inode
->root
;
5178 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
5179 struct btrfs_key key
;
5180 const u64 ino
= btrfs_ino(inode
);
5181 const u64 i_size
= i_size_read(&inode
->vfs_inode
);
5182 u64 prev_extent_end
= 0;
5185 if (!btrfs_fs_incompat(fs_info
, NO_HOLES
) || i_size
== 0)
5189 key
.type
= BTRFS_EXTENT_DATA_KEY
;
5192 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
5197 struct extent_buffer
*leaf
= path
->nodes
[0];
5199 if (path
->slots
[0] >= btrfs_header_nritems(path
->nodes
[0])) {
5200 ret
= btrfs_next_leaf(root
, path
);
5207 leaf
= path
->nodes
[0];
5210 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
5211 if (key
.objectid
!= ino
|| key
.type
!= BTRFS_EXTENT_DATA_KEY
)
5214 /* We have a hole, log it. */
5215 if (prev_extent_end
< key
.offset
) {
5216 const u64 hole_len
= key
.offset
- prev_extent_end
;
5219 * Release the path to avoid deadlocks with other code
5220 * paths that search the root while holding locks on
5221 * leafs from the log root.
5223 btrfs_release_path(path
);
5224 ret
= btrfs_insert_file_extent(trans
, root
->log_root
,
5225 ino
, prev_extent_end
, 0,
5226 0, hole_len
, 0, hole_len
,
5232 * Search for the same key again in the root. Since it's
5233 * an extent item and we are holding the inode lock, the
5234 * key must still exist. If it doesn't just emit warning
5235 * and return an error to fall back to a transaction
5238 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
5241 if (WARN_ON(ret
> 0))
5243 leaf
= path
->nodes
[0];
5246 prev_extent_end
= btrfs_file_extent_end(path
);
5251 if (prev_extent_end
< i_size
) {
5254 btrfs_release_path(path
);
5255 hole_len
= ALIGN(i_size
- prev_extent_end
, fs_info
->sectorsize
);
5256 ret
= btrfs_insert_file_extent(trans
, root
->log_root
,
5257 ino
, prev_extent_end
, 0, 0,
5258 hole_len
, 0, hole_len
,
5268 * When we are logging a new inode X, check if it doesn't have a reference that
5269 * matches the reference from some other inode Y created in a past transaction
5270 * and that was renamed in the current transaction. If we don't do this, then at
5271 * log replay time we can lose inode Y (and all its files if it's a directory):
5274 * echo "hello world" > /mnt/x/foobar
5277 * mkdir /mnt/x # or touch /mnt/x
5278 * xfs_io -c fsync /mnt/x
5280 * mount fs, trigger log replay
5282 * After the log replay procedure, we would lose the first directory and all its
5283 * files (file foobar).
5284 * For the case where inode Y is not a directory we simply end up losing it:
5286 * echo "123" > /mnt/foo
5288 * mv /mnt/foo /mnt/bar
5289 * echo "abc" > /mnt/foo
5290 * xfs_io -c fsync /mnt/foo
5293 * We also need this for cases where a snapshot entry is replaced by some other
5294 * entry (file or directory) otherwise we end up with an unreplayable log due to
5295 * attempts to delete the snapshot entry (entry of type BTRFS_ROOT_ITEM_KEY) as
5296 * if it were a regular entry:
5299 * btrfs subvolume snapshot /mnt /mnt/x/snap
5300 * btrfs subvolume delete /mnt/x/snap
5303 * fsync /mnt/x or fsync some new file inside it
5306 * The snapshot delete, rmdir of x, mkdir of a new x and the fsync all happen in
5307 * the same transaction.
5309 static int btrfs_check_ref_name_override(struct extent_buffer
*eb
,
5311 const struct btrfs_key
*key
,
5312 struct btrfs_inode
*inode
,
5313 u64
*other_ino
, u64
*other_parent
)
5316 struct btrfs_path
*search_path
;
5319 u32 item_size
= btrfs_item_size(eb
, slot
);
5321 unsigned long ptr
= btrfs_item_ptr_offset(eb
, slot
);
5323 search_path
= btrfs_alloc_path();
5326 search_path
->search_commit_root
= 1;
5327 search_path
->skip_locking
= 1;
5329 while (cur_offset
< item_size
) {
5333 unsigned long name_ptr
;
5334 struct btrfs_dir_item
*di
;
5336 if (key
->type
== BTRFS_INODE_REF_KEY
) {
5337 struct btrfs_inode_ref
*iref
;
5339 iref
= (struct btrfs_inode_ref
*)(ptr
+ cur_offset
);
5340 parent
= key
->offset
;
5341 this_name_len
= btrfs_inode_ref_name_len(eb
, iref
);
5342 name_ptr
= (unsigned long)(iref
+ 1);
5343 this_len
= sizeof(*iref
) + this_name_len
;
5345 struct btrfs_inode_extref
*extref
;
5347 extref
= (struct btrfs_inode_extref
*)(ptr
+
5349 parent
= btrfs_inode_extref_parent(eb
, extref
);
5350 this_name_len
= btrfs_inode_extref_name_len(eb
, extref
);
5351 name_ptr
= (unsigned long)&extref
->name
;
5352 this_len
= sizeof(*extref
) + this_name_len
;
5355 if (this_name_len
> name_len
) {
5358 new_name
= krealloc(name
, this_name_len
, GFP_NOFS
);
5363 name_len
= this_name_len
;
5367 read_extent_buffer(eb
, name
, name_ptr
, this_name_len
);
5368 di
= btrfs_lookup_dir_item(NULL
, inode
->root
, search_path
,
5369 parent
, name
, this_name_len
, 0);
5370 if (di
&& !IS_ERR(di
)) {
5371 struct btrfs_key di_key
;
5373 btrfs_dir_item_key_to_cpu(search_path
->nodes
[0],
5375 if (di_key
.type
== BTRFS_INODE_ITEM_KEY
) {
5376 if (di_key
.objectid
!= key
->objectid
) {
5378 *other_ino
= di_key
.objectid
;
5379 *other_parent
= parent
;
5387 } else if (IS_ERR(di
)) {
5391 btrfs_release_path(search_path
);
5393 cur_offset
+= this_len
;
5397 btrfs_free_path(search_path
);
5402 struct btrfs_ino_list
{
5405 struct list_head list
;
5408 static int log_conflicting_inodes(struct btrfs_trans_handle
*trans
,
5409 struct btrfs_root
*root
,
5410 struct btrfs_path
*path
,
5411 struct btrfs_log_ctx
*ctx
,
5412 u64 ino
, u64 parent
)
5414 struct btrfs_ino_list
*ino_elem
;
5415 LIST_HEAD(inode_list
);
5418 ino_elem
= kmalloc(sizeof(*ino_elem
), GFP_NOFS
);
5421 ino_elem
->ino
= ino
;
5422 ino_elem
->parent
= parent
;
5423 list_add_tail(&ino_elem
->list
, &inode_list
);
5425 while (!list_empty(&inode_list
)) {
5426 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
5427 struct btrfs_key key
;
5428 struct inode
*inode
;
5430 ino_elem
= list_first_entry(&inode_list
, struct btrfs_ino_list
,
5432 ino
= ino_elem
->ino
;
5433 parent
= ino_elem
->parent
;
5434 list_del(&ino_elem
->list
);
5439 btrfs_release_path(path
);
5441 inode
= btrfs_iget(fs_info
->sb
, ino
, root
);
5443 * If the other inode that had a conflicting dir entry was
5444 * deleted in the current transaction, we need to log its parent
5447 if (IS_ERR(inode
)) {
5448 ret
= PTR_ERR(inode
);
5449 if (ret
== -ENOENT
) {
5450 inode
= btrfs_iget(fs_info
->sb
, parent
, root
);
5451 if (IS_ERR(inode
)) {
5452 ret
= PTR_ERR(inode
);
5454 ret
= btrfs_log_inode(trans
,
5456 LOG_OTHER_INODE_ALL
,
5458 btrfs_add_delayed_iput(inode
);
5464 * If the inode was already logged skip it - otherwise we can
5465 * hit an infinite loop. Example:
5467 * From the commit root (previous transaction) we have the
5470 * inode 257 a directory
5471 * inode 258 with references "zz" and "zz_link" on inode 257
5472 * inode 259 with reference "a" on inode 257
5474 * And in the current (uncommitted) transaction we have:
5476 * inode 257 a directory, unchanged
5477 * inode 258 with references "a" and "a2" on inode 257
5478 * inode 259 with reference "zz_link" on inode 257
5479 * inode 261 with reference "zz" on inode 257
5481 * When logging inode 261 the following infinite loop could
5482 * happen if we don't skip already logged inodes:
5484 * - we detect inode 258 as a conflicting inode, with inode 261
5485 * on reference "zz", and log it;
5487 * - we detect inode 259 as a conflicting inode, with inode 258
5488 * on reference "a", and log it;
5490 * - we detect inode 258 as a conflicting inode, with inode 259
5491 * on reference "zz_link", and log it - again! After this we
5492 * repeat the above steps forever.
5494 spin_lock(&BTRFS_I(inode
)->lock
);
5496 * Check the inode's logged_trans only instead of
5497 * btrfs_inode_in_log(). This is because the last_log_commit of
5498 * the inode is not updated when we only log that it exists (see
5499 * btrfs_log_inode()).
5501 if (BTRFS_I(inode
)->logged_trans
== trans
->transid
) {
5502 spin_unlock(&BTRFS_I(inode
)->lock
);
5503 btrfs_add_delayed_iput(inode
);
5506 spin_unlock(&BTRFS_I(inode
)->lock
);
5508 * We are safe logging the other inode without acquiring its
5509 * lock as long as we log with the LOG_INODE_EXISTS mode. We
5510 * are safe against concurrent renames of the other inode as
5511 * well because during a rename we pin the log and update the
5512 * log with the new name before we unpin it.
5514 ret
= btrfs_log_inode(trans
, BTRFS_I(inode
), LOG_OTHER_INODE
, ctx
);
5516 btrfs_add_delayed_iput(inode
);
5521 key
.type
= BTRFS_INODE_REF_KEY
;
5523 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
5525 btrfs_add_delayed_iput(inode
);
5530 struct extent_buffer
*leaf
= path
->nodes
[0];
5531 int slot
= path
->slots
[0];
5533 u64 other_parent
= 0;
5535 if (slot
>= btrfs_header_nritems(leaf
)) {
5536 ret
= btrfs_next_leaf(root
, path
);
5539 } else if (ret
> 0) {
5546 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
5547 if (key
.objectid
!= ino
||
5548 (key
.type
!= BTRFS_INODE_REF_KEY
&&
5549 key
.type
!= BTRFS_INODE_EXTREF_KEY
)) {
5554 ret
= btrfs_check_ref_name_override(leaf
, slot
, &key
,
5555 BTRFS_I(inode
), &other_ino
,
5560 ino_elem
= kmalloc(sizeof(*ino_elem
), GFP_NOFS
);
5565 ino_elem
->ino
= other_ino
;
5566 ino_elem
->parent
= other_parent
;
5567 list_add_tail(&ino_elem
->list
, &inode_list
);
5572 btrfs_add_delayed_iput(inode
);
5578 static int copy_inode_items_to_log(struct btrfs_trans_handle
*trans
,
5579 struct btrfs_inode
*inode
,
5580 struct btrfs_key
*min_key
,
5581 const struct btrfs_key
*max_key
,
5582 struct btrfs_path
*path
,
5583 struct btrfs_path
*dst_path
,
5584 const u64 logged_isize
,
5585 const bool recursive_logging
,
5586 const int inode_only
,
5587 struct btrfs_log_ctx
*ctx
,
5588 bool *need_log_inode_item
)
5590 const u64 i_size
= i_size_read(&inode
->vfs_inode
);
5591 struct btrfs_root
*root
= inode
->root
;
5592 int ins_start_slot
= 0;
5597 ret
= btrfs_search_forward(root
, min_key
, path
, trans
->transid
);
5605 /* Note, ins_nr might be > 0 here, cleanup outside the loop */
5606 if (min_key
->objectid
!= max_key
->objectid
)
5608 if (min_key
->type
> max_key
->type
)
5611 if (min_key
->type
== BTRFS_INODE_ITEM_KEY
) {
5612 *need_log_inode_item
= false;
5613 } else if (min_key
->type
== BTRFS_EXTENT_DATA_KEY
&&
5614 min_key
->offset
>= i_size
) {
5616 * Extents at and beyond eof are logged with
5617 * btrfs_log_prealloc_extents().
5618 * Only regular files have BTRFS_EXTENT_DATA_KEY keys,
5619 * and no keys greater than that, so bail out.
5622 } else if ((min_key
->type
== BTRFS_INODE_REF_KEY
||
5623 min_key
->type
== BTRFS_INODE_EXTREF_KEY
) &&
5624 inode
->generation
== trans
->transid
&&
5625 !recursive_logging
) {
5627 u64 other_parent
= 0;
5629 ret
= btrfs_check_ref_name_override(path
->nodes
[0],
5630 path
->slots
[0], min_key
, inode
,
5631 &other_ino
, &other_parent
);
5634 } else if (ret
> 0 &&
5635 other_ino
!= btrfs_ino(BTRFS_I(ctx
->inode
))) {
5640 ins_start_slot
= path
->slots
[0];
5642 ret
= copy_items(trans
, inode
, dst_path
, path
,
5643 ins_start_slot
, ins_nr
,
5644 inode_only
, logged_isize
);
5649 ret
= log_conflicting_inodes(trans
, root
, path
,
5650 ctx
, other_ino
, other_parent
);
5653 btrfs_release_path(path
);
5656 } else if (min_key
->type
== BTRFS_XATTR_ITEM_KEY
) {
5657 /* Skip xattrs, logged later with btrfs_log_all_xattrs() */
5660 ret
= copy_items(trans
, inode
, dst_path
, path
,
5662 ins_nr
, inode_only
, logged_isize
);
5669 if (ins_nr
&& ins_start_slot
+ ins_nr
== path
->slots
[0]) {
5672 } else if (!ins_nr
) {
5673 ins_start_slot
= path
->slots
[0];
5678 ret
= copy_items(trans
, inode
, dst_path
, path
, ins_start_slot
,
5679 ins_nr
, inode_only
, logged_isize
);
5683 ins_start_slot
= path
->slots
[0];
5686 if (path
->slots
[0] < btrfs_header_nritems(path
->nodes
[0])) {
5687 btrfs_item_key_to_cpu(path
->nodes
[0], min_key
,
5692 ret
= copy_items(trans
, inode
, dst_path
, path
,
5693 ins_start_slot
, ins_nr
, inode_only
,
5699 btrfs_release_path(path
);
5701 if (min_key
->offset
< (u64
)-1) {
5703 } else if (min_key
->type
< max_key
->type
) {
5705 min_key
->offset
= 0;
5711 * We may process many leaves full of items for our inode, so
5712 * avoid monopolizing a cpu for too long by rescheduling while
5713 * not holding locks on any tree.
5718 ret
= copy_items(trans
, inode
, dst_path
, path
, ins_start_slot
,
5719 ins_nr
, inode_only
, logged_isize
);
5724 if (inode_only
== LOG_INODE_ALL
&& S_ISREG(inode
->vfs_inode
.i_mode
)) {
5726 * Release the path because otherwise we might attempt to double
5727 * lock the same leaf with btrfs_log_prealloc_extents() below.
5729 btrfs_release_path(path
);
5730 ret
= btrfs_log_prealloc_extents(trans
, inode
, dst_path
);
5736 /* log a single inode in the tree log.
5737 * At least one parent directory for this inode must exist in the tree
5738 * or be logged already.
5740 * Any items from this inode changed by the current transaction are copied
5741 * to the log tree. An extra reference is taken on any extents in this
5742 * file, allowing us to avoid a whole pile of corner cases around logging
5743 * blocks that have been removed from the tree.
5745 * See LOG_INODE_ALL and related defines for a description of what inode_only
5748 * This handles both files and directories.
5750 static int btrfs_log_inode(struct btrfs_trans_handle
*trans
,
5751 struct btrfs_inode
*inode
,
5753 struct btrfs_log_ctx
*ctx
)
5755 struct btrfs_path
*path
;
5756 struct btrfs_path
*dst_path
;
5757 struct btrfs_key min_key
;
5758 struct btrfs_key max_key
;
5759 struct btrfs_root
*log
= inode
->root
->log_root
;
5761 bool fast_search
= false;
5762 u64 ino
= btrfs_ino(inode
);
5763 struct extent_map_tree
*em_tree
= &inode
->extent_tree
;
5764 u64 logged_isize
= 0;
5765 bool need_log_inode_item
= true;
5766 bool xattrs_logged
= false;
5767 bool recursive_logging
= false;
5768 bool inode_item_dropped
= true;
5769 const bool orig_logged_before
= ctx
->logged_before
;
5771 path
= btrfs_alloc_path();
5774 dst_path
= btrfs_alloc_path();
5776 btrfs_free_path(path
);
5780 min_key
.objectid
= ino
;
5781 min_key
.type
= BTRFS_INODE_ITEM_KEY
;
5784 max_key
.objectid
= ino
;
5787 /* today the code can only do partial logging of directories */
5788 if (S_ISDIR(inode
->vfs_inode
.i_mode
) ||
5789 (!test_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
5790 &inode
->runtime_flags
) &&
5791 inode_only
>= LOG_INODE_EXISTS
))
5792 max_key
.type
= BTRFS_XATTR_ITEM_KEY
;
5794 max_key
.type
= (u8
)-1;
5795 max_key
.offset
= (u64
)-1;
5798 * Only run delayed items if we are a directory. We want to make sure
5799 * all directory indexes hit the fs/subvolume tree so we can find them
5800 * and figure out which index ranges have to be logged.
5802 if (S_ISDIR(inode
->vfs_inode
.i_mode
)) {
5803 ret
= btrfs_commit_inode_delayed_items(trans
, inode
);
5808 if (inode_only
== LOG_OTHER_INODE
|| inode_only
== LOG_OTHER_INODE_ALL
) {
5809 recursive_logging
= true;
5810 if (inode_only
== LOG_OTHER_INODE
)
5811 inode_only
= LOG_INODE_EXISTS
;
5813 inode_only
= LOG_INODE_ALL
;
5814 mutex_lock_nested(&inode
->log_mutex
, SINGLE_DEPTH_NESTING
);
5816 mutex_lock(&inode
->log_mutex
);
5820 * For symlinks, we must always log their content, which is stored in an
5821 * inline extent, otherwise we could end up with an empty symlink after
5822 * log replay, which is invalid on linux (symlink(2) returns -ENOENT if
5823 * one attempts to create an empty symlink).
5824 * We don't need to worry about flushing delalloc, because when we create
5825 * the inline extent when the symlink is created (we never have delalloc
5828 if (S_ISLNK(inode
->vfs_inode
.i_mode
))
5829 inode_only
= LOG_INODE_ALL
;
5832 * Before logging the inode item, cache the value returned by
5833 * inode_logged(), because after that we have the need to figure out if
5834 * the inode was previously logged in this transaction.
5836 ret
= inode_logged(trans
, inode
, path
);
5839 ctx
->logged_before
= (ret
== 1);
5843 * This is for cases where logging a directory could result in losing a
5844 * a file after replaying the log. For example, if we move a file from a
5845 * directory A to a directory B, then fsync directory A, we have no way
5846 * to known the file was moved from A to B, so logging just A would
5847 * result in losing the file after a log replay.
5849 if (S_ISDIR(inode
->vfs_inode
.i_mode
) &&
5850 inode_only
== LOG_INODE_ALL
&&
5851 inode
->last_unlink_trans
>= trans
->transid
) {
5852 btrfs_set_log_full_commit(trans
);
5853 ret
= BTRFS_LOG_FORCE_COMMIT
;
5858 * a brute force approach to making sure we get the most uptodate
5859 * copies of everything.
5861 if (S_ISDIR(inode
->vfs_inode
.i_mode
)) {
5862 int max_key_type
= BTRFS_DIR_LOG_INDEX_KEY
;
5864 clear_bit(BTRFS_INODE_COPY_EVERYTHING
, &inode
->runtime_flags
);
5865 if (inode_only
== LOG_INODE_EXISTS
)
5866 max_key_type
= BTRFS_XATTR_ITEM_KEY
;
5867 if (ctx
->logged_before
)
5868 ret
= drop_inode_items(trans
, log
, path
, inode
,
5871 if (inode_only
== LOG_INODE_EXISTS
&& ctx
->logged_before
) {
5873 * Make sure the new inode item we write to the log has
5874 * the same isize as the current one (if it exists).
5875 * This is necessary to prevent data loss after log
5876 * replay, and also to prevent doing a wrong expanding
5877 * truncate - for e.g. create file, write 4K into offset
5878 * 0, fsync, write 4K into offset 4096, add hard link,
5879 * fsync some other file (to sync log), power fail - if
5880 * we use the inode's current i_size, after log replay
5881 * we get a 8Kb file, with the last 4Kb extent as a hole
5882 * (zeroes), as if an expanding truncate happened,
5883 * instead of getting a file of 4Kb only.
5885 ret
= logged_inode_size(log
, inode
, path
, &logged_isize
);
5889 if (test_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
5890 &inode
->runtime_flags
)) {
5891 if (inode_only
== LOG_INODE_EXISTS
) {
5892 max_key
.type
= BTRFS_XATTR_ITEM_KEY
;
5893 if (ctx
->logged_before
)
5894 ret
= drop_inode_items(trans
, log
, path
,
5895 inode
, max_key
.type
);
5897 clear_bit(BTRFS_INODE_NEEDS_FULL_SYNC
,
5898 &inode
->runtime_flags
);
5899 clear_bit(BTRFS_INODE_COPY_EVERYTHING
,
5900 &inode
->runtime_flags
);
5901 if (ctx
->logged_before
)
5902 ret
= truncate_inode_items(trans
, log
,
5905 } else if (test_and_clear_bit(BTRFS_INODE_COPY_EVERYTHING
,
5906 &inode
->runtime_flags
) ||
5907 inode_only
== LOG_INODE_EXISTS
) {
5908 if (inode_only
== LOG_INODE_ALL
)
5910 max_key
.type
= BTRFS_XATTR_ITEM_KEY
;
5911 if (ctx
->logged_before
)
5912 ret
= drop_inode_items(trans
, log
, path
, inode
,
5915 if (inode_only
== LOG_INODE_ALL
)
5917 inode_item_dropped
= false;
5925 ret
= copy_inode_items_to_log(trans
, inode
, &min_key
, &max_key
,
5926 path
, dst_path
, logged_isize
,
5927 recursive_logging
, inode_only
, ctx
,
5928 &need_log_inode_item
);
5932 btrfs_release_path(path
);
5933 btrfs_release_path(dst_path
);
5934 ret
= btrfs_log_all_xattrs(trans
, inode
, path
, dst_path
);
5937 xattrs_logged
= true;
5938 if (max_key
.type
>= BTRFS_EXTENT_DATA_KEY
&& !fast_search
) {
5939 btrfs_release_path(path
);
5940 btrfs_release_path(dst_path
);
5941 ret
= btrfs_log_holes(trans
, inode
, path
);
5946 btrfs_release_path(path
);
5947 btrfs_release_path(dst_path
);
5948 if (need_log_inode_item
) {
5949 ret
= log_inode_item(trans
, log
, dst_path
, inode
, inode_item_dropped
);
5953 * If we are doing a fast fsync and the inode was logged before
5954 * in this transaction, we don't need to log the xattrs because
5955 * they were logged before. If xattrs were added, changed or
5956 * deleted since the last time we logged the inode, then we have
5957 * already logged them because the inode had the runtime flag
5958 * BTRFS_INODE_COPY_EVERYTHING set.
5960 if (!xattrs_logged
&& inode
->logged_trans
< trans
->transid
) {
5961 ret
= btrfs_log_all_xattrs(trans
, inode
, path
, dst_path
);
5964 btrfs_release_path(path
);
5968 ret
= btrfs_log_changed_extents(trans
, inode
, dst_path
, ctx
);
5971 } else if (inode_only
== LOG_INODE_ALL
) {
5972 struct extent_map
*em
, *n
;
5974 write_lock(&em_tree
->lock
);
5975 list_for_each_entry_safe(em
, n
, &em_tree
->modified_extents
, list
)
5976 list_del_init(&em
->list
);
5977 write_unlock(&em_tree
->lock
);
5980 if (inode_only
== LOG_INODE_ALL
&& S_ISDIR(inode
->vfs_inode
.i_mode
)) {
5981 ret
= log_directory_changes(trans
, inode
, path
, dst_path
, ctx
);
5986 spin_lock(&inode
->lock
);
5987 inode
->logged_trans
= trans
->transid
;
5989 * Don't update last_log_commit if we logged that an inode exists.
5990 * We do this for three reasons:
5992 * 1) We might have had buffered writes to this inode that were
5993 * flushed and had their ordered extents completed in this
5994 * transaction, but we did not previously log the inode with
5995 * LOG_INODE_ALL. Later the inode was evicted and after that
5996 * it was loaded again and this LOG_INODE_EXISTS log operation
5997 * happened. We must make sure that if an explicit fsync against
5998 * the inode is performed later, it logs the new extents, an
5999 * updated inode item, etc, and syncs the log. The same logic
6000 * applies to direct IO writes instead of buffered writes.
6002 * 2) When we log the inode with LOG_INODE_EXISTS, its inode item
6003 * is logged with an i_size of 0 or whatever value was logged
6004 * before. If later the i_size of the inode is increased by a
6005 * truncate operation, the log is synced through an fsync of
6006 * some other inode and then finally an explicit fsync against
6007 * this inode is made, we must make sure this fsync logs the
6008 * inode with the new i_size, the hole between old i_size and
6009 * the new i_size, and syncs the log.
6011 * 3) If we are logging that an ancestor inode exists as part of
6012 * logging a new name from a link or rename operation, don't update
6013 * its last_log_commit - otherwise if an explicit fsync is made
6014 * against an ancestor, the fsync considers the inode in the log
6015 * and doesn't sync the log, resulting in the ancestor missing after
6016 * a power failure unless the log was synced as part of an fsync
6017 * against any other unrelated inode.
6019 if (inode_only
!= LOG_INODE_EXISTS
)
6020 inode
->last_log_commit
= inode
->last_sub_trans
;
6021 spin_unlock(&inode
->lock
);
6024 * Reset the last_reflink_trans so that the next fsync does not need to
6025 * go through the slower path when logging extents and their checksums.
6027 if (inode_only
== LOG_INODE_ALL
)
6028 inode
->last_reflink_trans
= 0;
6031 mutex_unlock(&inode
->log_mutex
);
6033 btrfs_free_path(path
);
6034 btrfs_free_path(dst_path
);
6036 if (recursive_logging
)
6037 ctx
->logged_before
= orig_logged_before
;
6043 * Check if we need to log an inode. This is used in contexts where while
6044 * logging an inode we need to log another inode (either that it exists or in
6045 * full mode). This is used instead of btrfs_inode_in_log() because the later
6046 * requires the inode to be in the log and have the log transaction committed,
6047 * while here we do not care if the log transaction was already committed - our
6048 * caller will commit the log later - and we want to avoid logging an inode
6049 * multiple times when multiple tasks have joined the same log transaction.
6051 static bool need_log_inode(struct btrfs_trans_handle
*trans
,
6052 struct btrfs_inode
*inode
)
6055 * If a directory was not modified, no dentries added or removed, we can
6056 * and should avoid logging it.
6058 if (S_ISDIR(inode
->vfs_inode
.i_mode
) && inode
->last_trans
< trans
->transid
)
6062 * If this inode does not have new/updated/deleted xattrs since the last
6063 * time it was logged and is flagged as logged in the current transaction,
6064 * we can skip logging it. As for new/deleted names, those are updated in
6065 * the log by link/unlink/rename operations.
6066 * In case the inode was logged and then evicted and reloaded, its
6067 * logged_trans will be 0, in which case we have to fully log it since
6068 * logged_trans is a transient field, not persisted.
6070 if (inode
->logged_trans
== trans
->transid
&&
6071 !test_bit(BTRFS_INODE_COPY_EVERYTHING
, &inode
->runtime_flags
))
6077 struct btrfs_dir_list
{
6079 struct list_head list
;
6083 * Log the inodes of the new dentries of a directory. See log_dir_items() for
6084 * details about the why it is needed.
6085 * This is a recursive operation - if an existing dentry corresponds to a
6086 * directory, that directory's new entries are logged too (same behaviour as
6087 * ext3/4, xfs, f2fs, reiserfs, nilfs2). Note that when logging the inodes
6088 * the dentries point to we do not lock their i_mutex, otherwise lockdep
6089 * complains about the following circular lock dependency / possible deadlock:
6093 * lock(&type->i_mutex_dir_key#3/2);
6094 * lock(sb_internal#2);
6095 * lock(&type->i_mutex_dir_key#3/2);
6096 * lock(&sb->s_type->i_mutex_key#14);
6098 * Where sb_internal is the lock (a counter that works as a lock) acquired by
6099 * sb_start_intwrite() in btrfs_start_transaction().
6100 * Not locking i_mutex of the inodes is still safe because:
6102 * 1) For regular files we log with a mode of LOG_INODE_EXISTS. It's possible
6103 * that while logging the inode new references (names) are added or removed
6104 * from the inode, leaving the logged inode item with a link count that does
6105 * not match the number of logged inode reference items. This is fine because
6106 * at log replay time we compute the real number of links and correct the
6107 * link count in the inode item (see replay_one_buffer() and
6108 * link_to_fixup_dir());
6110 * 2) For directories we log with a mode of LOG_INODE_ALL. It's possible that
6111 * while logging the inode's items new index items (key type
6112 * BTRFS_DIR_INDEX_KEY) are added to fs/subvol tree and the logged inode item
6113 * has a size that doesn't match the sum of the lengths of all the logged
6114 * names - this is ok, not a problem, because at log replay time we set the
6115 * directory's i_size to the correct value (see replay_one_name() and
6116 * do_overwrite_item()).
6118 static int log_new_dir_dentries(struct btrfs_trans_handle
*trans
,
6119 struct btrfs_root
*root
,
6120 struct btrfs_inode
*start_inode
,
6121 struct btrfs_log_ctx
*ctx
)
6123 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
6124 struct btrfs_path
*path
;
6125 LIST_HEAD(dir_list
);
6126 struct btrfs_dir_list
*dir_elem
;
6130 * If we are logging a new name, as part of a link or rename operation,
6131 * don't bother logging new dentries, as we just want to log the names
6132 * of an inode and that any new parents exist.
6134 if (ctx
->logging_new_name
)
6137 path
= btrfs_alloc_path();
6141 dir_elem
= kmalloc(sizeof(*dir_elem
), GFP_NOFS
);
6143 btrfs_free_path(path
);
6146 dir_elem
->ino
= btrfs_ino(start_inode
);
6147 list_add_tail(&dir_elem
->list
, &dir_list
);
6149 while (!list_empty(&dir_list
)) {
6150 struct extent_buffer
*leaf
;
6151 struct btrfs_key min_key
;
6155 dir_elem
= list_first_entry(&dir_list
, struct btrfs_dir_list
,
6158 goto next_dir_inode
;
6160 min_key
.objectid
= dir_elem
->ino
;
6161 min_key
.type
= BTRFS_DIR_INDEX_KEY
;
6164 btrfs_release_path(path
);
6165 ret
= btrfs_search_forward(root
, &min_key
, path
, trans
->transid
);
6167 goto next_dir_inode
;
6168 } else if (ret
> 0) {
6170 goto next_dir_inode
;
6173 leaf
= path
->nodes
[0];
6174 nritems
= btrfs_header_nritems(leaf
);
6175 for (i
= path
->slots
[0]; i
< nritems
; i
++) {
6176 struct btrfs_dir_item
*di
;
6177 struct btrfs_key di_key
;
6178 struct inode
*di_inode
;
6179 struct btrfs_dir_list
*new_dir_elem
;
6180 int log_mode
= LOG_INODE_EXISTS
;
6183 btrfs_item_key_to_cpu(leaf
, &min_key
, i
);
6184 if (min_key
.objectid
!= dir_elem
->ino
||
6185 min_key
.type
!= BTRFS_DIR_INDEX_KEY
)
6186 goto next_dir_inode
;
6188 di
= btrfs_item_ptr(leaf
, i
, struct btrfs_dir_item
);
6189 type
= btrfs_dir_type(leaf
, di
);
6190 if (btrfs_dir_transid(leaf
, di
) < trans
->transid
)
6192 btrfs_dir_item_key_to_cpu(leaf
, di
, &di_key
);
6193 if (di_key
.type
== BTRFS_ROOT_ITEM_KEY
)
6196 btrfs_release_path(path
);
6197 di_inode
= btrfs_iget(fs_info
->sb
, di_key
.objectid
, root
);
6198 if (IS_ERR(di_inode
)) {
6199 ret
= PTR_ERR(di_inode
);
6200 goto next_dir_inode
;
6203 if (!need_log_inode(trans
, BTRFS_I(di_inode
))) {
6204 btrfs_add_delayed_iput(di_inode
);
6208 ctx
->log_new_dentries
= false;
6209 if (type
== BTRFS_FT_DIR
)
6210 log_mode
= LOG_INODE_ALL
;
6211 ret
= btrfs_log_inode(trans
, BTRFS_I(di_inode
),
6213 btrfs_add_delayed_iput(di_inode
);
6215 goto next_dir_inode
;
6216 if (ctx
->log_new_dentries
) {
6217 new_dir_elem
= kmalloc(sizeof(*new_dir_elem
),
6219 if (!new_dir_elem
) {
6221 goto next_dir_inode
;
6223 new_dir_elem
->ino
= di_key
.objectid
;
6224 list_add_tail(&new_dir_elem
->list
, &dir_list
);
6228 if (min_key
.offset
< (u64
)-1) {
6233 list_del(&dir_elem
->list
);
6237 btrfs_free_path(path
);
6241 static int btrfs_log_all_parents(struct btrfs_trans_handle
*trans
,
6242 struct btrfs_inode
*inode
,
6243 struct btrfs_log_ctx
*ctx
)
6245 struct btrfs_fs_info
*fs_info
= trans
->fs_info
;
6247 struct btrfs_path
*path
;
6248 struct btrfs_key key
;
6249 struct btrfs_root
*root
= inode
->root
;
6250 const u64 ino
= btrfs_ino(inode
);
6252 path
= btrfs_alloc_path();
6255 path
->skip_locking
= 1;
6256 path
->search_commit_root
= 1;
6259 key
.type
= BTRFS_INODE_REF_KEY
;
6261 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
6266 struct extent_buffer
*leaf
= path
->nodes
[0];
6267 int slot
= path
->slots
[0];
6272 if (slot
>= btrfs_header_nritems(leaf
)) {
6273 ret
= btrfs_next_leaf(root
, path
);
6281 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
6282 /* BTRFS_INODE_EXTREF_KEY is BTRFS_INODE_REF_KEY + 1 */
6283 if (key
.objectid
!= ino
|| key
.type
> BTRFS_INODE_EXTREF_KEY
)
6286 item_size
= btrfs_item_size(leaf
, slot
);
6287 ptr
= btrfs_item_ptr_offset(leaf
, slot
);
6288 while (cur_offset
< item_size
) {
6289 struct btrfs_key inode_key
;
6290 struct inode
*dir_inode
;
6292 inode_key
.type
= BTRFS_INODE_ITEM_KEY
;
6293 inode_key
.offset
= 0;
6295 if (key
.type
== BTRFS_INODE_EXTREF_KEY
) {
6296 struct btrfs_inode_extref
*extref
;
6298 extref
= (struct btrfs_inode_extref
*)
6300 inode_key
.objectid
= btrfs_inode_extref_parent(
6302 cur_offset
+= sizeof(*extref
);
6303 cur_offset
+= btrfs_inode_extref_name_len(leaf
,
6306 inode_key
.objectid
= key
.offset
;
6307 cur_offset
= item_size
;
6310 dir_inode
= btrfs_iget(fs_info
->sb
, inode_key
.objectid
,
6313 * If the parent inode was deleted, return an error to
6314 * fallback to a transaction commit. This is to prevent
6315 * getting an inode that was moved from one parent A to
6316 * a parent B, got its former parent A deleted and then
6317 * it got fsync'ed, from existing at both parents after
6318 * a log replay (and the old parent still existing).
6325 * mv /mnt/B/bar /mnt/A/bar
6326 * mv -T /mnt/A /mnt/B
6330 * If we ignore the old parent B which got deleted,
6331 * after a log replay we would have file bar linked
6332 * at both parents and the old parent B would still
6335 if (IS_ERR(dir_inode
)) {
6336 ret
= PTR_ERR(dir_inode
);
6340 if (!need_log_inode(trans
, BTRFS_I(dir_inode
))) {
6341 btrfs_add_delayed_iput(dir_inode
);
6345 ctx
->log_new_dentries
= false;
6346 ret
= btrfs_log_inode(trans
, BTRFS_I(dir_inode
),
6347 LOG_INODE_ALL
, ctx
);
6348 if (!ret
&& ctx
->log_new_dentries
)
6349 ret
= log_new_dir_dentries(trans
, root
,
6350 BTRFS_I(dir_inode
), ctx
);
6351 btrfs_add_delayed_iput(dir_inode
);
6359 btrfs_free_path(path
);
6363 static int log_new_ancestors(struct btrfs_trans_handle
*trans
,
6364 struct btrfs_root
*root
,
6365 struct btrfs_path
*path
,
6366 struct btrfs_log_ctx
*ctx
)
6368 struct btrfs_key found_key
;
6370 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
, path
->slots
[0]);
6373 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
6374 struct extent_buffer
*leaf
= path
->nodes
[0];
6375 int slot
= path
->slots
[0];
6376 struct btrfs_key search_key
;
6377 struct inode
*inode
;
6381 btrfs_release_path(path
);
6383 ino
= found_key
.offset
;
6385 search_key
.objectid
= found_key
.offset
;
6386 search_key
.type
= BTRFS_INODE_ITEM_KEY
;
6387 search_key
.offset
= 0;
6388 inode
= btrfs_iget(fs_info
->sb
, ino
, root
);
6390 return PTR_ERR(inode
);
6392 if (BTRFS_I(inode
)->generation
>= trans
->transid
&&
6393 need_log_inode(trans
, BTRFS_I(inode
)))
6394 ret
= btrfs_log_inode(trans
, BTRFS_I(inode
),
6395 LOG_INODE_EXISTS
, ctx
);
6396 btrfs_add_delayed_iput(inode
);
6400 if (search_key
.objectid
== BTRFS_FIRST_FREE_OBJECTID
)
6403 search_key
.type
= BTRFS_INODE_REF_KEY
;
6404 ret
= btrfs_search_slot(NULL
, root
, &search_key
, path
, 0, 0);
6408 leaf
= path
->nodes
[0];
6409 slot
= path
->slots
[0];
6410 if (slot
>= btrfs_header_nritems(leaf
)) {
6411 ret
= btrfs_next_leaf(root
, path
);
6416 leaf
= path
->nodes
[0];
6417 slot
= path
->slots
[0];
6420 btrfs_item_key_to_cpu(leaf
, &found_key
, slot
);
6421 if (found_key
.objectid
!= search_key
.objectid
||
6422 found_key
.type
!= BTRFS_INODE_REF_KEY
)
6428 static int log_new_ancestors_fast(struct btrfs_trans_handle
*trans
,
6429 struct btrfs_inode
*inode
,
6430 struct dentry
*parent
,
6431 struct btrfs_log_ctx
*ctx
)
6433 struct btrfs_root
*root
= inode
->root
;
6434 struct dentry
*old_parent
= NULL
;
6435 struct super_block
*sb
= inode
->vfs_inode
.i_sb
;
6439 if (!parent
|| d_really_is_negative(parent
) ||
6443 inode
= BTRFS_I(d_inode(parent
));
6444 if (root
!= inode
->root
)
6447 if (inode
->generation
>= trans
->transid
&&
6448 need_log_inode(trans
, inode
)) {
6449 ret
= btrfs_log_inode(trans
, inode
,
6450 LOG_INODE_EXISTS
, ctx
);
6454 if (IS_ROOT(parent
))
6457 parent
= dget_parent(parent
);
6459 old_parent
= parent
;
6466 static int log_all_new_ancestors(struct btrfs_trans_handle
*trans
,
6467 struct btrfs_inode
*inode
,
6468 struct dentry
*parent
,
6469 struct btrfs_log_ctx
*ctx
)
6471 struct btrfs_root
*root
= inode
->root
;
6472 const u64 ino
= btrfs_ino(inode
);
6473 struct btrfs_path
*path
;
6474 struct btrfs_key search_key
;
6478 * For a single hard link case, go through a fast path that does not
6479 * need to iterate the fs/subvolume tree.
6481 if (inode
->vfs_inode
.i_nlink
< 2)
6482 return log_new_ancestors_fast(trans
, inode
, parent
, ctx
);
6484 path
= btrfs_alloc_path();
6488 search_key
.objectid
= ino
;
6489 search_key
.type
= BTRFS_INODE_REF_KEY
;
6490 search_key
.offset
= 0;
6492 ret
= btrfs_search_slot(NULL
, root
, &search_key
, path
, 0, 0);
6499 struct extent_buffer
*leaf
= path
->nodes
[0];
6500 int slot
= path
->slots
[0];
6501 struct btrfs_key found_key
;
6503 if (slot
>= btrfs_header_nritems(leaf
)) {
6504 ret
= btrfs_next_leaf(root
, path
);
6512 btrfs_item_key_to_cpu(leaf
, &found_key
, slot
);
6513 if (found_key
.objectid
!= ino
||
6514 found_key
.type
> BTRFS_INODE_EXTREF_KEY
)
6518 * Don't deal with extended references because they are rare
6519 * cases and too complex to deal with (we would need to keep
6520 * track of which subitem we are processing for each item in
6521 * this loop, etc). So just return some error to fallback to
6522 * a transaction commit.
6524 if (found_key
.type
== BTRFS_INODE_EXTREF_KEY
) {
6530 * Logging ancestors needs to do more searches on the fs/subvol
6531 * tree, so it releases the path as needed to avoid deadlocks.
6532 * Keep track of the last inode ref key and resume from that key
6533 * after logging all new ancestors for the current hard link.
6535 memcpy(&search_key
, &found_key
, sizeof(search_key
));
6537 ret
= log_new_ancestors(trans
, root
, path
, ctx
);
6540 btrfs_release_path(path
);
6545 btrfs_free_path(path
);
6550 * helper function around btrfs_log_inode to make sure newly created
6551 * parent directories also end up in the log. A minimal inode and backref
6552 * only logging is done of any parent directories that are older than
6553 * the last committed transaction
6555 static int btrfs_log_inode_parent(struct btrfs_trans_handle
*trans
,
6556 struct btrfs_inode
*inode
,
6557 struct dentry
*parent
,
6559 struct btrfs_log_ctx
*ctx
)
6561 struct btrfs_root
*root
= inode
->root
;
6562 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
6564 bool log_dentries
= false;
6566 if (btrfs_test_opt(fs_info
, NOTREELOG
)) {
6567 ret
= BTRFS_LOG_FORCE_COMMIT
;
6571 if (btrfs_root_refs(&root
->root_item
) == 0) {
6572 ret
= BTRFS_LOG_FORCE_COMMIT
;
6577 * Skip already logged inodes or inodes corresponding to tmpfiles
6578 * (since logging them is pointless, a link count of 0 means they
6579 * will never be accessible).
6581 if ((btrfs_inode_in_log(inode
, trans
->transid
) &&
6582 list_empty(&ctx
->ordered_extents
)) ||
6583 inode
->vfs_inode
.i_nlink
== 0) {
6584 ret
= BTRFS_NO_LOG_SYNC
;
6588 ret
= start_log_trans(trans
, root
, ctx
);
6592 ret
= btrfs_log_inode(trans
, inode
, inode_only
, ctx
);
6597 * for regular files, if its inode is already on disk, we don't
6598 * have to worry about the parents at all. This is because
6599 * we can use the last_unlink_trans field to record renames
6600 * and other fun in this file.
6602 if (S_ISREG(inode
->vfs_inode
.i_mode
) &&
6603 inode
->generation
< trans
->transid
&&
6604 inode
->last_unlink_trans
< trans
->transid
) {
6609 if (S_ISDIR(inode
->vfs_inode
.i_mode
) && ctx
->log_new_dentries
)
6610 log_dentries
= true;
6613 * On unlink we must make sure all our current and old parent directory
6614 * inodes are fully logged. This is to prevent leaving dangling
6615 * directory index entries in directories that were our parents but are
6616 * not anymore. Not doing this results in old parent directory being
6617 * impossible to delete after log replay (rmdir will always fail with
6618 * error -ENOTEMPTY).
6624 * ln testdir/foo testdir/bar
6626 * unlink testdir/bar
6627 * xfs_io -c fsync testdir/foo
6629 * mount fs, triggers log replay
6631 * If we don't log the parent directory (testdir), after log replay the
6632 * directory still has an entry pointing to the file inode using the bar
6633 * name, but a matching BTRFS_INODE_[REF|EXTREF]_KEY does not exist and
6634 * the file inode has a link count of 1.
6640 * ln foo testdir/foo2
6641 * ln foo testdir/foo3
6643 * unlink testdir/foo3
6644 * xfs_io -c fsync foo
6646 * mount fs, triggers log replay
6648 * Similar as the first example, after log replay the parent directory
6649 * testdir still has an entry pointing to the inode file with name foo3
6650 * but the file inode does not have a matching BTRFS_INODE_REF_KEY item
6651 * and has a link count of 2.
6653 if (inode
->last_unlink_trans
>= trans
->transid
) {
6654 ret
= btrfs_log_all_parents(trans
, inode
, ctx
);
6659 ret
= log_all_new_ancestors(trans
, inode
, parent
, ctx
);
6664 ret
= log_new_dir_dentries(trans
, root
, inode
, ctx
);
6669 btrfs_set_log_full_commit(trans
);
6670 ret
= BTRFS_LOG_FORCE_COMMIT
;
6674 btrfs_remove_log_ctx(root
, ctx
);
6675 btrfs_end_log_trans(root
);
6681 * it is not safe to log dentry if the chunk root has added new
6682 * chunks. This returns 0 if the dentry was logged, and 1 otherwise.
6683 * If this returns 1, you must commit the transaction to safely get your
6686 int btrfs_log_dentry_safe(struct btrfs_trans_handle
*trans
,
6687 struct dentry
*dentry
,
6688 struct btrfs_log_ctx
*ctx
)
6690 struct dentry
*parent
= dget_parent(dentry
);
6693 ret
= btrfs_log_inode_parent(trans
, BTRFS_I(d_inode(dentry
)), parent
,
6694 LOG_INODE_ALL
, ctx
);
6701 * should be called during mount to recover any replay any log trees
6704 int btrfs_recover_log_trees(struct btrfs_root
*log_root_tree
)
6707 struct btrfs_path
*path
;
6708 struct btrfs_trans_handle
*trans
;
6709 struct btrfs_key key
;
6710 struct btrfs_key found_key
;
6711 struct btrfs_root
*log
;
6712 struct btrfs_fs_info
*fs_info
= log_root_tree
->fs_info
;
6713 struct walk_control wc
= {
6714 .process_func
= process_one_buffer
,
6715 .stage
= LOG_WALK_PIN_ONLY
,
6718 path
= btrfs_alloc_path();
6722 set_bit(BTRFS_FS_LOG_RECOVERING
, &fs_info
->flags
);
6724 trans
= btrfs_start_transaction(fs_info
->tree_root
, 0);
6725 if (IS_ERR(trans
)) {
6726 ret
= PTR_ERR(trans
);
6733 ret
= walk_log_tree(trans
, log_root_tree
, &wc
);
6735 btrfs_abort_transaction(trans
, ret
);
6740 key
.objectid
= BTRFS_TREE_LOG_OBJECTID
;
6741 key
.offset
= (u64
)-1;
6742 key
.type
= BTRFS_ROOT_ITEM_KEY
;
6745 ret
= btrfs_search_slot(NULL
, log_root_tree
, &key
, path
, 0, 0);
6748 btrfs_abort_transaction(trans
, ret
);
6752 if (path
->slots
[0] == 0)
6756 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
,
6758 btrfs_release_path(path
);
6759 if (found_key
.objectid
!= BTRFS_TREE_LOG_OBJECTID
)
6762 log
= btrfs_read_tree_root(log_root_tree
, &found_key
);
6765 btrfs_abort_transaction(trans
, ret
);
6769 wc
.replay_dest
= btrfs_get_fs_root(fs_info
, found_key
.offset
,
6771 if (IS_ERR(wc
.replay_dest
)) {
6772 ret
= PTR_ERR(wc
.replay_dest
);
6775 * We didn't find the subvol, likely because it was
6776 * deleted. This is ok, simply skip this log and go to
6779 * We need to exclude the root because we can't have
6780 * other log replays overwriting this log as we'll read
6781 * it back in a few more times. This will keep our
6782 * block from being modified, and we'll just bail for
6783 * each subsequent pass.
6786 ret
= btrfs_pin_extent_for_log_replay(trans
,
6789 btrfs_put_root(log
);
6793 btrfs_abort_transaction(trans
, ret
);
6797 wc
.replay_dest
->log_root
= log
;
6798 ret
= btrfs_record_root_in_trans(trans
, wc
.replay_dest
);
6800 /* The loop needs to continue due to the root refs */
6801 btrfs_abort_transaction(trans
, ret
);
6803 ret
= walk_log_tree(trans
, log
, &wc
);
6805 if (!ret
&& wc
.stage
== LOG_WALK_REPLAY_ALL
) {
6806 ret
= fixup_inode_link_counts(trans
, wc
.replay_dest
,
6809 btrfs_abort_transaction(trans
, ret
);
6812 if (!ret
&& wc
.stage
== LOG_WALK_REPLAY_ALL
) {
6813 struct btrfs_root
*root
= wc
.replay_dest
;
6815 btrfs_release_path(path
);
6818 * We have just replayed everything, and the highest
6819 * objectid of fs roots probably has changed in case
6820 * some inode_item's got replayed.
6822 * root->objectid_mutex is not acquired as log replay
6823 * could only happen during mount.
6825 ret
= btrfs_init_root_free_objectid(root
);
6827 btrfs_abort_transaction(trans
, ret
);
6830 wc
.replay_dest
->log_root
= NULL
;
6831 btrfs_put_root(wc
.replay_dest
);
6832 btrfs_put_root(log
);
6837 if (found_key
.offset
== 0)
6839 key
.offset
= found_key
.offset
- 1;
6841 btrfs_release_path(path
);
6843 /* step one is to pin it all, step two is to replay just inodes */
6846 wc
.process_func
= replay_one_buffer
;
6847 wc
.stage
= LOG_WALK_REPLAY_INODES
;
6850 /* step three is to replay everything */
6851 if (wc
.stage
< LOG_WALK_REPLAY_ALL
) {
6856 btrfs_free_path(path
);
6858 /* step 4: commit the transaction, which also unpins the blocks */
6859 ret
= btrfs_commit_transaction(trans
);
6863 log_root_tree
->log_root
= NULL
;
6864 clear_bit(BTRFS_FS_LOG_RECOVERING
, &fs_info
->flags
);
6865 btrfs_put_root(log_root_tree
);
6870 btrfs_end_transaction(wc
.trans
);
6871 clear_bit(BTRFS_FS_LOG_RECOVERING
, &fs_info
->flags
);
6872 btrfs_free_path(path
);
6877 * there are some corner cases where we want to force a full
6878 * commit instead of allowing a directory to be logged.
6880 * They revolve around files there were unlinked from the directory, and
6881 * this function updates the parent directory so that a full commit is
6882 * properly done if it is fsync'd later after the unlinks are done.
6884 * Must be called before the unlink operations (updates to the subvolume tree,
6885 * inodes, etc) are done.
6887 void btrfs_record_unlink_dir(struct btrfs_trans_handle
*trans
,
6888 struct btrfs_inode
*dir
, struct btrfs_inode
*inode
,
6892 * when we're logging a file, if it hasn't been renamed
6893 * or unlinked, and its inode is fully committed on disk,
6894 * we don't have to worry about walking up the directory chain
6895 * to log its parents.
6897 * So, we use the last_unlink_trans field to put this transid
6898 * into the file. When the file is logged we check it and
6899 * don't log the parents if the file is fully on disk.
6901 mutex_lock(&inode
->log_mutex
);
6902 inode
->last_unlink_trans
= trans
->transid
;
6903 mutex_unlock(&inode
->log_mutex
);
6906 * if this directory was already logged any new
6907 * names for this file/dir will get recorded
6909 if (dir
->logged_trans
== trans
->transid
)
6913 * if the inode we're about to unlink was logged,
6914 * the log will be properly updated for any new names
6916 if (inode
->logged_trans
== trans
->transid
)
6920 * when renaming files across directories, if the directory
6921 * there we're unlinking from gets fsync'd later on, there's
6922 * no way to find the destination directory later and fsync it
6923 * properly. So, we have to be conservative and force commits
6924 * so the new name gets discovered.
6929 /* we can safely do the unlink without any special recording */
6933 mutex_lock(&dir
->log_mutex
);
6934 dir
->last_unlink_trans
= trans
->transid
;
6935 mutex_unlock(&dir
->log_mutex
);
6939 * Make sure that if someone attempts to fsync the parent directory of a deleted
6940 * snapshot, it ends up triggering a transaction commit. This is to guarantee
6941 * that after replaying the log tree of the parent directory's root we will not
6942 * see the snapshot anymore and at log replay time we will not see any log tree
6943 * corresponding to the deleted snapshot's root, which could lead to replaying
6944 * it after replaying the log tree of the parent directory (which would replay
6945 * the snapshot delete operation).
6947 * Must be called before the actual snapshot destroy operation (updates to the
6948 * parent root and tree of tree roots trees, etc) are done.
6950 void btrfs_record_snapshot_destroy(struct btrfs_trans_handle
*trans
,
6951 struct btrfs_inode
*dir
)
6953 mutex_lock(&dir
->log_mutex
);
6954 dir
->last_unlink_trans
= trans
->transid
;
6955 mutex_unlock(&dir
->log_mutex
);
6959 * Update the log after adding a new name for an inode.
6961 * @trans: Transaction handle.
6962 * @old_dentry: The dentry associated with the old name and the old
6964 * @old_dir: The inode of the previous parent directory for the case
6965 * of a rename. For a link operation, it must be NULL.
6966 * @old_dir_index: The index number associated with the old name, meaningful
6967 * only for rename operations (when @old_dir is not NULL).
6968 * Ignored for link operations.
6969 * @parent: The dentry associated with the directory under which the
6970 * new name is located.
6972 * Call this after adding a new name for an inode, as a result of a link or
6973 * rename operation, and it will properly update the log to reflect the new name.
6975 void btrfs_log_new_name(struct btrfs_trans_handle
*trans
,
6976 struct dentry
*old_dentry
, struct btrfs_inode
*old_dir
,
6977 u64 old_dir_index
, struct dentry
*parent
)
6979 struct btrfs_inode
*inode
= BTRFS_I(d_inode(old_dentry
));
6980 struct btrfs_root
*root
= inode
->root
;
6981 struct btrfs_log_ctx ctx
;
6982 bool log_pinned
= false;
6986 * this will force the logging code to walk the dentry chain
6989 if (!S_ISDIR(inode
->vfs_inode
.i_mode
))
6990 inode
->last_unlink_trans
= trans
->transid
;
6993 * if this inode hasn't been logged and directory we're renaming it
6994 * from hasn't been logged, we don't need to log it
6996 ret
= inode_logged(trans
, inode
, NULL
);
6999 } else if (ret
== 0) {
7003 * If the inode was not logged and we are doing a rename (old_dir is not
7004 * NULL), check if old_dir was logged - if it was not we can return and
7007 ret
= inode_logged(trans
, old_dir
, NULL
);
7016 * If we are doing a rename (old_dir is not NULL) from a directory that
7017 * was previously logged, make sure that on log replay we get the old
7018 * dir entry deleted. This is needed because we will also log the new
7019 * name of the renamed inode, so we need to make sure that after log
7020 * replay we don't end up with both the new and old dir entries existing.
7022 if (old_dir
&& old_dir
->logged_trans
== trans
->transid
) {
7023 struct btrfs_root
*log
= old_dir
->root
->log_root
;
7024 struct btrfs_path
*path
;
7026 ASSERT(old_dir_index
>= BTRFS_DIR_START_INDEX
);
7029 * We have two inodes to update in the log, the old directory and
7030 * the inode that got renamed, so we must pin the log to prevent
7031 * anyone from syncing the log until we have updated both inodes
7034 ret
= join_running_log_trans(root
);
7036 * At least one of the inodes was logged before, so this should
7037 * not fail, but if it does, it's not serious, just bail out and
7038 * mark the log for a full commit.
7040 if (WARN_ON_ONCE(ret
< 0))
7044 path
= btrfs_alloc_path();
7051 * Other concurrent task might be logging the old directory,
7052 * as it can be triggered when logging other inode that had or
7053 * still has a dentry in the old directory. We lock the old
7054 * directory's log_mutex to ensure the deletion of the old
7055 * name is persisted, because during directory logging we
7056 * delete all BTRFS_DIR_LOG_INDEX_KEY keys and the deletion of
7057 * the old name's dir index item is in the delayed items, so
7058 * it could be missed by an in progress directory logging.
7060 mutex_lock(&old_dir
->log_mutex
);
7061 ret
= del_logged_dentry(trans
, log
, path
, btrfs_ino(old_dir
),
7062 old_dentry
->d_name
.name
,
7063 old_dentry
->d_name
.len
, old_dir_index
);
7066 * The dentry does not exist in the log, so record its
7069 btrfs_release_path(path
);
7070 ret
= insert_dir_log_key(trans
, log
, path
,
7072 old_dir_index
, old_dir_index
);
7074 mutex_unlock(&old_dir
->log_mutex
);
7076 btrfs_free_path(path
);
7081 btrfs_init_log_ctx(&ctx
, &inode
->vfs_inode
);
7082 ctx
.logging_new_name
= true;
7084 * We don't care about the return value. If we fail to log the new name
7085 * then we know the next attempt to sync the log will fallback to a full
7086 * transaction commit (due to a call to btrfs_set_log_full_commit()), so
7087 * we don't need to worry about getting a log committed that has an
7088 * inconsistent state after a rename operation.
7090 btrfs_log_inode_parent(trans
, inode
, parent
, LOG_INODE_EXISTS
, &ctx
);
7093 * If an error happened mark the log for a full commit because it's not
7094 * consistent and up to date or we couldn't find out if one of the
7095 * inodes was logged before in this transaction. Do it before unpinning
7096 * the log, to avoid any races with someone else trying to commit it.
7099 btrfs_set_log_full_commit(trans
);
7101 btrfs_end_log_trans(root
);