2 * Copyright (C) 2008 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
19 #include <linux/sched.h>
21 #include "transaction.h"
24 #include "print-tree.h"
27 /* magic values for the inode_only field in btrfs_log_inode:
29 * LOG_INODE_ALL means to log everything
30 * LOG_INODE_EXISTS means to log just enough to recreate the inode
33 #define LOG_INODE_ALL 0
34 #define LOG_INODE_EXISTS 1
37 * stages for the tree walking. The first
38 * stage (0) is to only pin down the blocks we find
39 * the second stage (1) is to make sure that all the inodes
40 * we find in the log are created in the subvolume.
42 * The last stage is to deal with directories and links and extents
43 * and all the other fun semantics
45 #define LOG_WALK_PIN_ONLY 0
46 #define LOG_WALK_REPLAY_INODES 1
47 #define LOG_WALK_REPLAY_ALL 2
49 static int __btrfs_log_inode(struct btrfs_trans_handle
*trans
,
50 struct btrfs_root
*root
, struct inode
*inode
,
54 * tree logging is a special write ahead log used to make sure that
55 * fsyncs and O_SYNCs can happen without doing full tree commits.
57 * Full tree commits are expensive because they require commonly
58 * modified blocks to be recowed, creating many dirty pages in the
59 * extent tree an 4x-6x higher write load than ext3.
61 * Instead of doing a tree commit on every fsync, we use the
62 * key ranges and transaction ids to find items for a given file or directory
63 * that have changed in this transaction. Those items are copied into
64 * a special tree (one per subvolume root), that tree is written to disk
65 * and then the fsync is considered complete.
67 * After a crash, items are copied out of the log-tree back into the
68 * subvolume tree. Any file data extents found are recorded in the extent
69 * allocation tree, and the log-tree freed.
71 * The log tree is read three times, once to pin down all the extents it is
72 * using in ram and once, once to create all the inodes logged in the tree
73 * and once to do all the other items.
77 * btrfs_add_log_tree adds a new per-subvolume log tree into the
78 * tree of log tree roots. This must be called with a tree log transaction
79 * running (see start_log_trans).
81 int btrfs_add_log_tree(struct btrfs_trans_handle
*trans
,
82 struct btrfs_root
*root
)
85 struct btrfs_root_item root_item
;
86 struct btrfs_inode_item
*inode_item
;
87 struct extent_buffer
*leaf
;
88 struct btrfs_root
*new_root
= root
;
90 u64 objectid
= root
->root_key
.objectid
;
92 leaf
= btrfs_alloc_free_block(trans
, root
, root
->leafsize
, 0,
93 BTRFS_TREE_LOG_OBJECTID
,
94 trans
->transid
, 0, 0, 0);
100 btrfs_set_header_nritems(leaf
, 0);
101 btrfs_set_header_level(leaf
, 0);
102 btrfs_set_header_bytenr(leaf
, leaf
->start
);
103 btrfs_set_header_generation(leaf
, trans
->transid
);
104 btrfs_set_header_owner(leaf
, BTRFS_TREE_LOG_OBJECTID
);
106 write_extent_buffer(leaf
, root
->fs_info
->fsid
,
107 (unsigned long)btrfs_header_fsid(leaf
),
109 btrfs_mark_buffer_dirty(leaf
);
111 inode_item
= &root_item
.inode
;
112 memset(inode_item
, 0, sizeof(*inode_item
));
113 inode_item
->generation
= cpu_to_le64(1);
114 inode_item
->size
= cpu_to_le64(3);
115 inode_item
->nlink
= cpu_to_le32(1);
116 inode_item
->nblocks
= cpu_to_le64(1);
117 inode_item
->mode
= cpu_to_le32(S_IFDIR
| 0755);
119 btrfs_set_root_bytenr(&root_item
, leaf
->start
);
120 btrfs_set_root_level(&root_item
, 0);
121 btrfs_set_root_refs(&root_item
, 0);
122 btrfs_set_root_used(&root_item
, 0);
124 memset(&root_item
.drop_progress
, 0, sizeof(root_item
.drop_progress
));
125 root_item
.drop_level
= 0;
127 btrfs_tree_unlock(leaf
);
128 free_extent_buffer(leaf
);
131 btrfs_set_root_dirid(&root_item
, 0);
133 key
.objectid
= BTRFS_TREE_LOG_OBJECTID
;
134 key
.offset
= objectid
;
135 btrfs_set_key_type(&key
, BTRFS_ROOT_ITEM_KEY
);
136 ret
= btrfs_insert_root(trans
, root
->fs_info
->log_root_tree
, &key
,
141 new_root
= btrfs_read_fs_root_no_radix(root
->fs_info
->log_root_tree
,
145 WARN_ON(root
->log_root
);
146 root
->log_root
= new_root
;
149 * log trees do not get reference counted because they go away
150 * before a real commit is actually done. They do store pointers
151 * to file data extents, and those reference counts still get
152 * updated (along with back refs to the log tree).
154 new_root
->ref_cows
= 0;
155 new_root
->last_trans
= trans
->transid
;
161 * start a sub transaction and setup the log tree
162 * this increments the log tree writer count to make the people
163 * syncing the tree wait for us to finish
165 static int start_log_trans(struct btrfs_trans_handle
*trans
,
166 struct btrfs_root
*root
)
169 mutex_lock(&root
->fs_info
->tree_log_mutex
);
170 if (!root
->fs_info
->log_root_tree
) {
171 ret
= btrfs_init_log_root_tree(trans
, root
->fs_info
);
174 if (!root
->log_root
) {
175 ret
= btrfs_add_log_tree(trans
, root
);
178 atomic_inc(&root
->fs_info
->tree_log_writers
);
179 root
->fs_info
->tree_log_batch
++;
180 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
185 * returns 0 if there was a log transaction running and we were able
186 * to join, or returns -ENOENT if there were not transactions
189 static int join_running_log_trans(struct btrfs_root
*root
)
197 mutex_lock(&root
->fs_info
->tree_log_mutex
);
198 if (root
->log_root
) {
200 atomic_inc(&root
->fs_info
->tree_log_writers
);
201 root
->fs_info
->tree_log_batch
++;
203 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
208 * indicate we're done making changes to the log tree
209 * and wake up anyone waiting to do a sync
211 static int end_log_trans(struct btrfs_root
*root
)
213 atomic_dec(&root
->fs_info
->tree_log_writers
);
215 if (waitqueue_active(&root
->fs_info
->tree_log_wait
))
216 wake_up(&root
->fs_info
->tree_log_wait
);
222 * the walk control struct is used to pass state down the chain when
223 * processing the log tree. The stage field tells us which part
224 * of the log tree processing we are currently doing. The others
225 * are state fields used for that specific part
227 struct walk_control
{
228 /* should we free the extent on disk when done? This is used
229 * at transaction commit time while freeing a log tree
233 /* should we write out the extent buffer? This is used
234 * while flushing the log tree to disk during a sync
238 /* should we wait for the extent buffer io to finish? Also used
239 * while flushing the log tree to disk for a sync
243 /* pin only walk, we record which extents on disk belong to the
248 /* what stage of the replay code we're currently in */
251 /* the root we are currently replaying */
252 struct btrfs_root
*replay_dest
;
254 /* the trans handle for the current replay */
255 struct btrfs_trans_handle
*trans
;
257 /* the function that gets used to process blocks we find in the
258 * tree. Note the extent_buffer might not be up to date when it is
259 * passed in, and it must be checked or read if you need the data
262 int (*process_func
)(struct btrfs_root
*log
, struct extent_buffer
*eb
,
263 struct walk_control
*wc
, u64 gen
);
267 * process_func used to pin down extents, write them or wait on them
269 static int process_one_buffer(struct btrfs_root
*log
,
270 struct extent_buffer
*eb
,
271 struct walk_control
*wc
, u64 gen
)
274 mutex_lock(&log
->fs_info
->alloc_mutex
);
275 btrfs_update_pinned_extents(log
->fs_info
->extent_root
,
276 eb
->start
, eb
->len
, 1);
277 mutex_unlock(&log
->fs_info
->alloc_mutex
);
280 if (btrfs_buffer_uptodate(eb
, gen
)) {
282 btrfs_write_tree_block(eb
);
284 btrfs_wait_tree_block_writeback(eb
);
290 * Item overwrite used by replay and tree logging. eb, slot and key all refer
291 * to the src data we are copying out.
293 * root is the tree we are copying into, and path is a scratch
294 * path for use in this function (it should be released on entry and
295 * will be released on exit).
297 * If the key is already in the destination tree the existing item is
298 * overwritten. If the existing item isn't big enough, it is extended.
299 * If it is too large, it is truncated.
301 * If the key isn't in the destination yet, a new item is inserted.
303 static noinline
int overwrite_item(struct btrfs_trans_handle
*trans
,
304 struct btrfs_root
*root
,
305 struct btrfs_path
*path
,
306 struct extent_buffer
*eb
, int slot
,
307 struct btrfs_key
*key
)
311 u64 saved_i_size
= 0;
312 int save_old_i_size
= 0;
313 unsigned long src_ptr
;
314 unsigned long dst_ptr
;
315 int overwrite_root
= 0;
317 if (root
->root_key
.objectid
!= BTRFS_TREE_LOG_OBJECTID
)
320 item_size
= btrfs_item_size_nr(eb
, slot
);
321 src_ptr
= btrfs_item_ptr_offset(eb
, slot
);
323 /* look for the key in the destination tree */
324 ret
= btrfs_search_slot(NULL
, root
, key
, path
, 0, 0);
328 u32 dst_size
= btrfs_item_size_nr(path
->nodes
[0],
330 if (dst_size
!= item_size
)
333 if (item_size
== 0) {
334 btrfs_release_path(root
, path
);
337 dst_copy
= kmalloc(item_size
, GFP_NOFS
);
338 src_copy
= kmalloc(item_size
, GFP_NOFS
);
340 read_extent_buffer(eb
, src_copy
, src_ptr
, item_size
);
342 dst_ptr
= btrfs_item_ptr_offset(path
->nodes
[0], path
->slots
[0]);
343 read_extent_buffer(path
->nodes
[0], dst_copy
, dst_ptr
,
345 ret
= memcmp(dst_copy
, src_copy
, item_size
);
350 * they have the same contents, just return, this saves
351 * us from cowing blocks in the destination tree and doing
352 * extra writes that may not have been done by a previous
356 btrfs_release_path(root
, path
);
362 btrfs_release_path(root
, path
);
363 /* try to insert the key into the destination tree */
364 ret
= btrfs_insert_empty_item(trans
, root
, path
,
367 /* make sure any existing item is the correct size */
368 if (ret
== -EEXIST
) {
370 found_size
= btrfs_item_size_nr(path
->nodes
[0],
372 if (found_size
> item_size
) {
373 btrfs_truncate_item(trans
, root
, path
, item_size
, 1);
374 } else if (found_size
< item_size
) {
375 ret
= btrfs_del_item(trans
, root
,
379 btrfs_release_path(root
, path
);
380 ret
= btrfs_insert_empty_item(trans
,
381 root
, path
, key
, item_size
);
387 dst_ptr
= btrfs_item_ptr_offset(path
->nodes
[0],
390 /* don't overwrite an existing inode if the generation number
391 * was logged as zero. This is done when the tree logging code
392 * is just logging an inode to make sure it exists after recovery.
394 * Also, don't overwrite i_size on directories during replay.
395 * log replay inserts and removes directory items based on the
396 * state of the tree found in the subvolume, and i_size is modified
399 if (key
->type
== BTRFS_INODE_ITEM_KEY
&& ret
== -EEXIST
) {
400 struct btrfs_inode_item
*src_item
;
401 struct btrfs_inode_item
*dst_item
;
403 src_item
= (struct btrfs_inode_item
*)src_ptr
;
404 dst_item
= (struct btrfs_inode_item
*)dst_ptr
;
406 if (btrfs_inode_generation(eb
, src_item
) == 0)
409 if (overwrite_root
&&
410 S_ISDIR(btrfs_inode_mode(eb
, src_item
)) &&
411 S_ISDIR(btrfs_inode_mode(path
->nodes
[0], dst_item
))) {
413 saved_i_size
= btrfs_inode_size(path
->nodes
[0],
418 copy_extent_buffer(path
->nodes
[0], eb
, dst_ptr
,
421 if (save_old_i_size
) {
422 struct btrfs_inode_item
*dst_item
;
423 dst_item
= (struct btrfs_inode_item
*)dst_ptr
;
424 btrfs_set_inode_size(path
->nodes
[0], dst_item
, saved_i_size
);
427 /* make sure the generation is filled in */
428 if (key
->type
== BTRFS_INODE_ITEM_KEY
) {
429 struct btrfs_inode_item
*dst_item
;
430 dst_item
= (struct btrfs_inode_item
*)dst_ptr
;
431 if (btrfs_inode_generation(path
->nodes
[0], dst_item
) == 0) {
432 btrfs_set_inode_generation(path
->nodes
[0], dst_item
,
437 if (overwrite_root
&&
438 key
->type
== BTRFS_EXTENT_DATA_KEY
) {
440 struct btrfs_file_extent_item
*fi
;
442 fi
= (struct btrfs_file_extent_item
*)dst_ptr
;
443 extent_type
= btrfs_file_extent_type(path
->nodes
[0], fi
);
444 if (extent_type
== BTRFS_FILE_EXTENT_REG
) {
445 struct btrfs_key ins
;
446 ins
.objectid
= btrfs_file_extent_disk_bytenr(
448 ins
.offset
= btrfs_file_extent_disk_num_bytes(
450 ins
.type
= BTRFS_EXTENT_ITEM_KEY
;
453 * is this extent already allocated in the extent
454 * allocation tree? If so, just add a reference
456 ret
= btrfs_lookup_extent(root
, ins
.objectid
,
459 ret
= btrfs_inc_extent_ref(trans
, root
,
460 ins
.objectid
, ins
.offset
,
461 path
->nodes
[0]->start
,
462 root
->root_key
.objectid
,
464 key
->objectid
, key
->offset
);
467 * insert the extent pointer in the extent
470 ret
= btrfs_alloc_logged_extent(trans
, root
,
471 path
->nodes
[0]->start
,
472 root
->root_key
.objectid
,
473 trans
->transid
, key
->objectid
,
480 btrfs_mark_buffer_dirty(path
->nodes
[0]);
481 btrfs_release_path(root
, path
);
486 * simple helper to read an inode off the disk from a given root
487 * This can only be called for subvolume roots and not for the log
489 static noinline
struct inode
*read_one_inode(struct btrfs_root
*root
,
493 inode
= btrfs_iget_locked(root
->fs_info
->sb
, objectid
, root
);
494 if (inode
->i_state
& I_NEW
) {
495 BTRFS_I(inode
)->root
= root
;
496 BTRFS_I(inode
)->location
.objectid
= objectid
;
497 BTRFS_I(inode
)->location
.type
= BTRFS_INODE_ITEM_KEY
;
498 BTRFS_I(inode
)->location
.offset
= 0;
499 btrfs_read_locked_inode(inode
);
500 unlock_new_inode(inode
);
503 if (is_bad_inode(inode
)) {
510 /* replays a single extent in 'eb' at 'slot' with 'key' into the
511 * subvolume 'root'. path is released on entry and should be released
514 * extents in the log tree have not been allocated out of the extent
515 * tree yet. So, this completes the allocation, taking a reference
516 * as required if the extent already exists or creating a new extent
517 * if it isn't in the extent allocation tree yet.
519 * The extent is inserted into the file, dropping any existing extents
520 * from the file that overlap the new one.
522 static noinline
int replay_one_extent(struct btrfs_trans_handle
*trans
,
523 struct btrfs_root
*root
,
524 struct btrfs_path
*path
,
525 struct extent_buffer
*eb
, int slot
,
526 struct btrfs_key
*key
)
529 u64 mask
= root
->sectorsize
- 1;
532 u64 start
= key
->offset
;
533 struct btrfs_file_extent_item
*item
;
534 struct inode
*inode
= NULL
;
538 item
= btrfs_item_ptr(eb
, slot
, struct btrfs_file_extent_item
);
539 found_type
= btrfs_file_extent_type(eb
, item
);
541 if (found_type
== BTRFS_FILE_EXTENT_REG
)
542 extent_end
= start
+ btrfs_file_extent_num_bytes(eb
, item
);
543 else if (found_type
== BTRFS_FILE_EXTENT_INLINE
) {
544 size
= btrfs_file_extent_inline_len(eb
,
545 btrfs_item_nr(eb
, slot
));
546 extent_end
= (start
+ size
+ mask
) & ~mask
;
552 inode
= read_one_inode(root
, key
->objectid
);
559 * first check to see if we already have this extent in the
560 * file. This must be done before the btrfs_drop_extents run
561 * so we don't try to drop this extent.
563 ret
= btrfs_lookup_file_extent(trans
, root
, path
, inode
->i_ino
,
566 if (ret
== 0 && found_type
== BTRFS_FILE_EXTENT_REG
) {
567 struct btrfs_file_extent_item cmp1
;
568 struct btrfs_file_extent_item cmp2
;
569 struct btrfs_file_extent_item
*existing
;
570 struct extent_buffer
*leaf
;
572 leaf
= path
->nodes
[0];
573 existing
= btrfs_item_ptr(leaf
, path
->slots
[0],
574 struct btrfs_file_extent_item
);
576 read_extent_buffer(eb
, &cmp1
, (unsigned long)item
,
578 read_extent_buffer(leaf
, &cmp2
, (unsigned long)existing
,
582 * we already have a pointer to this exact extent,
583 * we don't have to do anything
585 if (memcmp(&cmp1
, &cmp2
, sizeof(cmp1
)) == 0) {
586 btrfs_release_path(root
, path
);
590 btrfs_release_path(root
, path
);
592 /* drop any overlapping extents */
593 ret
= btrfs_drop_extents(trans
, root
, inode
,
594 start
, extent_end
, start
, &alloc_hint
);
597 /* insert the extent */
598 ret
= overwrite_item(trans
, root
, path
, eb
, slot
, key
);
601 /* btrfs_drop_extents changes i_blocks, update it here */
602 inode
->i_blocks
+= (extent_end
- start
) >> 9;
603 btrfs_update_inode(trans
, root
, inode
);
611 * when cleaning up conflicts between the directory names in the
612 * subvolume, directory names in the log and directory names in the
613 * inode back references, we may have to unlink inodes from directories.
615 * This is a helper function to do the unlink of a specific directory
618 static noinline
int drop_one_dir_item(struct btrfs_trans_handle
*trans
,
619 struct btrfs_root
*root
,
620 struct btrfs_path
*path
,
622 struct btrfs_dir_item
*di
)
627 struct extent_buffer
*leaf
;
628 struct btrfs_key location
;
631 leaf
= path
->nodes
[0];
633 btrfs_dir_item_key_to_cpu(leaf
, di
, &location
);
634 name_len
= btrfs_dir_name_len(leaf
, di
);
635 name
= kmalloc(name_len
, GFP_NOFS
);
636 read_extent_buffer(leaf
, name
, (unsigned long)(di
+ 1), name_len
);
637 btrfs_release_path(root
, path
);
639 inode
= read_one_inode(root
, location
.objectid
);
642 btrfs_inc_nlink(inode
);
643 ret
= btrfs_unlink_inode(trans
, root
, dir
, inode
, name
, name_len
);
651 * helper function to see if a given name and sequence number found
652 * in an inode back reference are already in a directory and correctly
653 * point to this inode
655 static noinline
int inode_in_dir(struct btrfs_root
*root
,
656 struct btrfs_path
*path
,
657 u64 dirid
, u64 objectid
, u64 index
,
658 const char *name
, int name_len
)
660 struct btrfs_dir_item
*di
;
661 struct btrfs_key location
;
664 di
= btrfs_lookup_dir_index_item(NULL
, root
, path
, dirid
,
665 index
, name
, name_len
, 0);
666 if (di
&& !IS_ERR(di
)) {
667 btrfs_dir_item_key_to_cpu(path
->nodes
[0], di
, &location
);
668 if (location
.objectid
!= objectid
)
672 btrfs_release_path(root
, path
);
674 di
= btrfs_lookup_dir_item(NULL
, root
, path
, dirid
, name
, name_len
, 0);
675 if (di
&& !IS_ERR(di
)) {
676 btrfs_dir_item_key_to_cpu(path
->nodes
[0], di
, &location
);
677 if (location
.objectid
!= objectid
)
683 btrfs_release_path(root
, path
);
688 * helper function to check a log tree for a named back reference in
689 * an inode. This is used to decide if a back reference that is
690 * found in the subvolume conflicts with what we find in the log.
692 * inode backreferences may have multiple refs in a single item,
693 * during replay we process one reference at a time, and we don't
694 * want to delete valid links to a file from the subvolume if that
695 * link is also in the log.
697 static noinline
int backref_in_log(struct btrfs_root
*log
,
698 struct btrfs_key
*key
,
699 char *name
, int namelen
)
701 struct btrfs_path
*path
;
702 struct btrfs_inode_ref
*ref
;
704 unsigned long ptr_end
;
705 unsigned long name_ptr
;
711 path
= btrfs_alloc_path();
712 ret
= btrfs_search_slot(NULL
, log
, key
, path
, 0, 0);
716 item_size
= btrfs_item_size_nr(path
->nodes
[0], path
->slots
[0]);
717 ptr
= btrfs_item_ptr_offset(path
->nodes
[0], path
->slots
[0]);
718 ptr_end
= ptr
+ item_size
;
719 while (ptr
< ptr_end
) {
720 ref
= (struct btrfs_inode_ref
*)ptr
;
721 found_name_len
= btrfs_inode_ref_name_len(path
->nodes
[0], ref
);
722 if (found_name_len
== namelen
) {
723 name_ptr
= (unsigned long)(ref
+ 1);
724 ret
= memcmp_extent_buffer(path
->nodes
[0], name
,
731 ptr
= (unsigned long)(ref
+ 1) + found_name_len
;
734 btrfs_free_path(path
);
740 * replay one inode back reference item found in the log tree.
741 * eb, slot and key refer to the buffer and key found in the log tree.
742 * root is the destination we are replaying into, and path is for temp
743 * use by this function. (it should be released on return).
745 static noinline
int add_inode_ref(struct btrfs_trans_handle
*trans
,
746 struct btrfs_root
*root
,
747 struct btrfs_root
*log
,
748 struct btrfs_path
*path
,
749 struct extent_buffer
*eb
, int slot
,
750 struct btrfs_key
*key
)
754 struct btrfs_key location
;
755 struct btrfs_inode_ref
*ref
;
756 struct btrfs_dir_item
*di
;
760 unsigned long ref_ptr
;
761 unsigned long ref_end
;
763 location
.objectid
= key
->objectid
;
764 location
.type
= BTRFS_INODE_ITEM_KEY
;
768 * it is possible that we didn't log all the parent directories
769 * for a given inode. If we don't find the dir, just don't
770 * copy the back ref in. The link count fixup code will take
773 dir
= read_one_inode(root
, key
->offset
);
777 inode
= read_one_inode(root
, key
->objectid
);
780 ref_ptr
= btrfs_item_ptr_offset(eb
, slot
);
781 ref_end
= ref_ptr
+ btrfs_item_size_nr(eb
, slot
);
784 ref
= (struct btrfs_inode_ref
*)ref_ptr
;
786 namelen
= btrfs_inode_ref_name_len(eb
, ref
);
787 name
= kmalloc(namelen
, GFP_NOFS
);
790 read_extent_buffer(eb
, name
, (unsigned long)(ref
+ 1), namelen
);
792 /* if we already have a perfect match, we're done */
793 if (inode_in_dir(root
, path
, dir
->i_ino
, inode
->i_ino
,
794 btrfs_inode_ref_index(eb
, ref
),
800 * look for a conflicting back reference in the metadata.
801 * if we find one we have to unlink that name of the file
802 * before we add our new link. Later on, we overwrite any
803 * existing back reference, and we don't want to create
804 * dangling pointers in the directory.
807 ret
= btrfs_search_slot(NULL
, root
, key
, path
, 0, 0);
811 struct btrfs_inode_ref
*victim_ref
;
813 unsigned long ptr_end
;
814 struct extent_buffer
*leaf
= path
->nodes
[0];
816 /* are we trying to overwrite a back ref for the root directory
817 * if so, just jump out, we're done
819 if (key
->objectid
== key
->offset
)
822 /* check all the names in this back reference to see
823 * if they are in the log. if so, we allow them to stay
824 * otherwise they must be unlinked as a conflict
826 ptr
= btrfs_item_ptr_offset(leaf
, path
->slots
[0]);
827 ptr_end
= ptr
+ btrfs_item_size_nr(leaf
, path
->slots
[0]);
828 while(ptr
< ptr_end
) {
829 victim_ref
= (struct btrfs_inode_ref
*)ptr
;
830 victim_name_len
= btrfs_inode_ref_name_len(leaf
,
832 victim_name
= kmalloc(victim_name_len
, GFP_NOFS
);
833 BUG_ON(!victim_name
);
835 read_extent_buffer(leaf
, victim_name
,
836 (unsigned long)(victim_ref
+ 1),
839 if (!backref_in_log(log
, key
, victim_name
,
841 btrfs_inc_nlink(inode
);
842 btrfs_release_path(root
, path
);
843 ret
= btrfs_unlink_inode(trans
, root
, dir
,
847 btrfs_release_path(root
, path
);
851 ptr
= (unsigned long)(victim_ref
+ 1) + victim_name_len
;
855 btrfs_release_path(root
, path
);
857 /* look for a conflicting sequence number */
858 di
= btrfs_lookup_dir_index_item(trans
, root
, path
, dir
->i_ino
,
859 btrfs_inode_ref_index(eb
, ref
),
861 if (di
&& !IS_ERR(di
)) {
862 ret
= drop_one_dir_item(trans
, root
, path
, dir
, di
);
865 btrfs_release_path(root
, path
);
868 /* look for a conflicting name */
869 di
= btrfs_lookup_dir_item(trans
, root
, path
, dir
->i_ino
,
871 if (di
&& !IS_ERR(di
)) {
872 ret
= drop_one_dir_item(trans
, root
, path
, dir
, di
);
875 btrfs_release_path(root
, path
);
877 /* insert our name */
878 ret
= btrfs_add_link(trans
, dir
, inode
, name
, namelen
, 0,
879 btrfs_inode_ref_index(eb
, ref
));
882 btrfs_update_inode(trans
, root
, inode
);
885 ref_ptr
= (unsigned long)(ref
+ 1) + namelen
;
887 if (ref_ptr
< ref_end
)
890 /* finally write the back reference in the inode */
891 ret
= overwrite_item(trans
, root
, path
, eb
, slot
, key
);
895 btrfs_release_path(root
, path
);
902 * replay one csum item from the log tree into the subvolume 'root'
903 * eb, slot and key all refer to the log tree
904 * path is for temp use by this function and should be released on return
906 * This copies the checksums out of the log tree and inserts them into
907 * the subvolume. Any existing checksums for this range in the file
908 * are overwritten, and new items are added where required.
910 * We keep this simple by reusing the btrfs_ordered_sum code from
911 * the data=ordered mode. This basically means making a copy
912 * of all the checksums in ram, which we have to do anyway for kmap
915 * The copy is then sent down to btrfs_csum_file_blocks, which
916 * does all the hard work of finding existing items in the file
917 * or adding new ones.
919 static noinline
int replay_one_csum(struct btrfs_trans_handle
*trans
,
920 struct btrfs_root
*root
,
921 struct btrfs_path
*path
,
922 struct extent_buffer
*eb
, int slot
,
923 struct btrfs_key
*key
)
926 u32 item_size
= btrfs_item_size_nr(eb
, slot
);
928 unsigned long file_bytes
;
929 struct btrfs_ordered_sum
*sums
;
930 struct btrfs_sector_sum
*sector_sum
;
934 file_bytes
= (item_size
/ BTRFS_CRC32_SIZE
) * root
->sectorsize
;
935 inode
= read_one_inode(root
, key
->objectid
);
940 sums
= kzalloc(btrfs_ordered_sum_size(root
, file_bytes
), GFP_NOFS
);
946 INIT_LIST_HEAD(&sums
->list
);
947 sums
->len
= file_bytes
;
948 sums
->file_offset
= key
->offset
;
951 * copy all the sums into the ordered sum struct
953 sector_sum
= sums
->sums
;
954 cur_offset
= key
->offset
;
955 ptr
= btrfs_item_ptr_offset(eb
, slot
);
956 while(item_size
> 0) {
957 sector_sum
->offset
= cur_offset
;
958 read_extent_buffer(eb
, §or_sum
->sum
, ptr
, BTRFS_CRC32_SIZE
);
960 item_size
-= BTRFS_CRC32_SIZE
;
961 ptr
+= BTRFS_CRC32_SIZE
;
962 cur_offset
+= root
->sectorsize
;
965 /* let btrfs_csum_file_blocks add them into the file */
966 ret
= btrfs_csum_file_blocks(trans
, root
, inode
, sums
);
974 * There are a few corners where the link count of the file can't
975 * be properly maintained during replay. So, instead of adding
976 * lots of complexity to the log code, we just scan the backrefs
977 * for any file that has been through replay.
979 * The scan will update the link count on the inode to reflect the
980 * number of back refs found. If it goes down to zero, the iput
981 * will free the inode.
983 static noinline
int fixup_inode_link_count(struct btrfs_trans_handle
*trans
,
984 struct btrfs_root
*root
,
987 struct btrfs_path
*path
;
989 struct btrfs_key key
;
992 unsigned long ptr_end
;
995 key
.objectid
= inode
->i_ino
;
996 key
.type
= BTRFS_INODE_REF_KEY
;
997 key
.offset
= (u64
)-1;
999 path
= btrfs_alloc_path();
1002 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
1006 if (path
->slots
[0] == 0)
1010 btrfs_item_key_to_cpu(path
->nodes
[0], &key
,
1012 if (key
.objectid
!= inode
->i_ino
||
1013 key
.type
!= BTRFS_INODE_REF_KEY
)
1015 ptr
= btrfs_item_ptr_offset(path
->nodes
[0], path
->slots
[0]);
1016 ptr_end
= ptr
+ btrfs_item_size_nr(path
->nodes
[0],
1018 while(ptr
< ptr_end
) {
1019 struct btrfs_inode_ref
*ref
;
1021 ref
= (struct btrfs_inode_ref
*)ptr
;
1022 name_len
= btrfs_inode_ref_name_len(path
->nodes
[0],
1024 ptr
= (unsigned long)(ref
+ 1) + name_len
;
1028 if (key
.offset
== 0)
1031 btrfs_release_path(root
, path
);
1033 btrfs_free_path(path
);
1034 if (nlink
!= inode
->i_nlink
) {
1035 inode
->i_nlink
= nlink
;
1036 btrfs_update_inode(trans
, root
, inode
);
1038 BTRFS_I(inode
)->index_cnt
= (u64
)-1;
1043 static noinline
int fixup_inode_link_counts(struct btrfs_trans_handle
*trans
,
1044 struct btrfs_root
*root
,
1045 struct btrfs_path
*path
)
1048 struct btrfs_key key
;
1049 struct inode
*inode
;
1051 key
.objectid
= BTRFS_TREE_LOG_FIXUP_OBJECTID
;
1052 key
.type
= BTRFS_ORPHAN_ITEM_KEY
;
1053 key
.offset
= (u64
)-1;
1055 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
1060 if (path
->slots
[0] == 0)
1065 btrfs_item_key_to_cpu(path
->nodes
[0], &key
, path
->slots
[0]);
1066 if (key
.objectid
!= BTRFS_TREE_LOG_FIXUP_OBJECTID
||
1067 key
.type
!= BTRFS_ORPHAN_ITEM_KEY
)
1070 ret
= btrfs_del_item(trans
, root
, path
);
1073 btrfs_release_path(root
, path
);
1074 inode
= read_one_inode(root
, key
.offset
);
1077 ret
= fixup_inode_link_count(trans
, root
, inode
);
1082 if (key
.offset
== 0)
1086 btrfs_release_path(root
, path
);
1092 * record a given inode in the fixup dir so we can check its link
1093 * count when replay is done. The link count is incremented here
1094 * so the inode won't go away until we check it
1096 static noinline
int link_to_fixup_dir(struct btrfs_trans_handle
*trans
,
1097 struct btrfs_root
*root
,
1098 struct btrfs_path
*path
,
1101 struct btrfs_key key
;
1103 struct inode
*inode
;
1105 inode
= read_one_inode(root
, objectid
);
1108 key
.objectid
= BTRFS_TREE_LOG_FIXUP_OBJECTID
;
1109 btrfs_set_key_type(&key
, BTRFS_ORPHAN_ITEM_KEY
);
1110 key
.offset
= objectid
;
1112 ret
= btrfs_insert_empty_item(trans
, root
, path
, &key
, 0);
1114 btrfs_release_path(root
, path
);
1116 btrfs_inc_nlink(inode
);
1117 btrfs_update_inode(trans
, root
, inode
);
1118 } else if (ret
== -EEXIST
) {
1129 * when replaying the log for a directory, we only insert names
1130 * for inodes that actually exist. This means an fsync on a directory
1131 * does not implicitly fsync all the new files in it
1133 static noinline
int insert_one_name(struct btrfs_trans_handle
*trans
,
1134 struct btrfs_root
*root
,
1135 struct btrfs_path
*path
,
1136 u64 dirid
, u64 index
,
1137 char *name
, int name_len
, u8 type
,
1138 struct btrfs_key
*location
)
1140 struct inode
*inode
;
1144 inode
= read_one_inode(root
, location
->objectid
);
1148 dir
= read_one_inode(root
, dirid
);
1153 ret
= btrfs_add_link(trans
, dir
, inode
, name
, name_len
, 1, index
);
1155 /* FIXME, put inode into FIXUP list */
1163 * take a single entry in a log directory item and replay it into
1166 * if a conflicting item exists in the subdirectory already,
1167 * the inode it points to is unlinked and put into the link count
1170 * If a name from the log points to a file or directory that does
1171 * not exist in the FS, it is skipped. fsyncs on directories
1172 * do not force down inodes inside that directory, just changes to the
1173 * names or unlinks in a directory.
1175 static noinline
int replay_one_name(struct btrfs_trans_handle
*trans
,
1176 struct btrfs_root
*root
,
1177 struct btrfs_path
*path
,
1178 struct extent_buffer
*eb
,
1179 struct btrfs_dir_item
*di
,
1180 struct btrfs_key
*key
)
1184 struct btrfs_dir_item
*dst_di
;
1185 struct btrfs_key found_key
;
1186 struct btrfs_key log_key
;
1192 dir
= read_one_inode(root
, key
->objectid
);
1195 name_len
= btrfs_dir_name_len(eb
, di
);
1196 name
= kmalloc(name_len
, GFP_NOFS
);
1197 log_type
= btrfs_dir_type(eb
, di
);
1198 read_extent_buffer(eb
, name
, (unsigned long)(di
+ 1),
1201 btrfs_dir_item_key_to_cpu(eb
, di
, &log_key
);
1202 exists
= btrfs_lookup_inode(trans
, root
, path
, &log_key
, 0);
1207 btrfs_release_path(root
, path
);
1209 if (key
->type
== BTRFS_DIR_ITEM_KEY
) {
1210 dst_di
= btrfs_lookup_dir_item(trans
, root
, path
, key
->objectid
,
1213 else if (key
->type
== BTRFS_DIR_INDEX_KEY
) {
1214 dst_di
= btrfs_lookup_dir_index_item(trans
, root
, path
,
1221 if (!dst_di
|| IS_ERR(dst_di
)) {
1222 /* we need a sequence number to insert, so we only
1223 * do inserts for the BTRFS_DIR_INDEX_KEY types
1225 if (key
->type
!= BTRFS_DIR_INDEX_KEY
)
1230 btrfs_dir_item_key_to_cpu(path
->nodes
[0], dst_di
, &found_key
);
1231 /* the existing item matches the logged item */
1232 if (found_key
.objectid
== log_key
.objectid
&&
1233 found_key
.type
== log_key
.type
&&
1234 found_key
.offset
== log_key
.offset
&&
1235 btrfs_dir_type(path
->nodes
[0], dst_di
) == log_type
) {
1240 * don't drop the conflicting directory entry if the inode
1241 * for the new entry doesn't exist
1246 ret
= drop_one_dir_item(trans
, root
, path
, dir
, dst_di
);
1249 if (key
->type
== BTRFS_DIR_INDEX_KEY
)
1252 btrfs_release_path(root
, path
);
1258 btrfs_release_path(root
, path
);
1259 ret
= insert_one_name(trans
, root
, path
, key
->objectid
, key
->offset
,
1260 name
, name_len
, log_type
, &log_key
);
1262 if (ret
&& ret
!= -ENOENT
)
1268 * find all the names in a directory item and reconcile them into
1269 * the subvolume. Only BTRFS_DIR_ITEM_KEY types will have more than
1270 * one name in a directory item, but the same code gets used for
1271 * both directory index types
1273 static noinline
int replay_one_dir_item(struct btrfs_trans_handle
*trans
,
1274 struct btrfs_root
*root
,
1275 struct btrfs_path
*path
,
1276 struct extent_buffer
*eb
, int slot
,
1277 struct btrfs_key
*key
)
1280 u32 item_size
= btrfs_item_size_nr(eb
, slot
);
1281 struct btrfs_dir_item
*di
;
1284 unsigned long ptr_end
;
1286 ptr
= btrfs_item_ptr_offset(eb
, slot
);
1287 ptr_end
= ptr
+ item_size
;
1288 while(ptr
< ptr_end
) {
1289 di
= (struct btrfs_dir_item
*)ptr
;
1290 name_len
= btrfs_dir_name_len(eb
, di
);
1291 ret
= replay_one_name(trans
, root
, path
, eb
, di
, key
);
1293 ptr
= (unsigned long)(di
+ 1);
1300 * directory replay has two parts. There are the standard directory
1301 * items in the log copied from the subvolume, and range items
1302 * created in the log while the subvolume was logged.
1304 * The range items tell us which parts of the key space the log
1305 * is authoritative for. During replay, if a key in the subvolume
1306 * directory is in a logged range item, but not actually in the log
1307 * that means it was deleted from the directory before the fsync
1308 * and should be removed.
1310 static noinline
int find_dir_range(struct btrfs_root
*root
,
1311 struct btrfs_path
*path
,
1312 u64 dirid
, int key_type
,
1313 u64
*start_ret
, u64
*end_ret
)
1315 struct btrfs_key key
;
1317 struct btrfs_dir_log_item
*item
;
1321 if (*start_ret
== (u64
)-1)
1324 key
.objectid
= dirid
;
1325 key
.type
= key_type
;
1326 key
.offset
= *start_ret
;
1328 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
1332 if (path
->slots
[0] == 0)
1337 btrfs_item_key_to_cpu(path
->nodes
[0], &key
, path
->slots
[0]);
1339 if (key
.type
!= key_type
|| key
.objectid
!= dirid
) {
1343 item
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
1344 struct btrfs_dir_log_item
);
1345 found_end
= btrfs_dir_log_end(path
->nodes
[0], item
);
1347 if (*start_ret
>= key
.offset
&& *start_ret
<= found_end
) {
1349 *start_ret
= key
.offset
;
1350 *end_ret
= found_end
;
1355 /* check the next slot in the tree to see if it is a valid item */
1356 nritems
= btrfs_header_nritems(path
->nodes
[0]);
1357 if (path
->slots
[0] >= nritems
) {
1358 ret
= btrfs_next_leaf(root
, path
);
1365 btrfs_item_key_to_cpu(path
->nodes
[0], &key
, path
->slots
[0]);
1367 if (key
.type
!= key_type
|| key
.objectid
!= dirid
) {
1371 item
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
1372 struct btrfs_dir_log_item
);
1373 found_end
= btrfs_dir_log_end(path
->nodes
[0], item
);
1374 *start_ret
= key
.offset
;
1375 *end_ret
= found_end
;
1378 btrfs_release_path(root
, path
);
1383 * this looks for a given directory item in the log. If the directory
1384 * item is not in the log, the item is removed and the inode it points
1387 static noinline
int check_item_in_log(struct btrfs_trans_handle
*trans
,
1388 struct btrfs_root
*root
,
1389 struct btrfs_root
*log
,
1390 struct btrfs_path
*path
,
1391 struct btrfs_path
*log_path
,
1393 struct btrfs_key
*dir_key
)
1396 struct extent_buffer
*eb
;
1399 struct btrfs_dir_item
*di
;
1400 struct btrfs_dir_item
*log_di
;
1403 unsigned long ptr_end
;
1405 struct inode
*inode
;
1406 struct btrfs_key location
;
1409 eb
= path
->nodes
[0];
1410 slot
= path
->slots
[0];
1411 item_size
= btrfs_item_size_nr(eb
, slot
);
1412 ptr
= btrfs_item_ptr_offset(eb
, slot
);
1413 ptr_end
= ptr
+ item_size
;
1414 while(ptr
< ptr_end
) {
1415 di
= (struct btrfs_dir_item
*)ptr
;
1416 name_len
= btrfs_dir_name_len(eb
, di
);
1417 name
= kmalloc(name_len
, GFP_NOFS
);
1422 read_extent_buffer(eb
, name
, (unsigned long)(di
+ 1),
1425 if (dir_key
->type
== BTRFS_DIR_ITEM_KEY
) {
1426 log_di
= btrfs_lookup_dir_item(trans
, log
, log_path
,
1429 } else if (dir_key
->type
== BTRFS_DIR_INDEX_KEY
) {
1430 log_di
= btrfs_lookup_dir_index_item(trans
, log
,
1436 if (!log_di
|| IS_ERR(log_di
)) {
1437 btrfs_dir_item_key_to_cpu(eb
, di
, &location
);
1438 btrfs_release_path(root
, path
);
1439 btrfs_release_path(log
, log_path
);
1440 inode
= read_one_inode(root
, location
.objectid
);
1443 ret
= link_to_fixup_dir(trans
, root
,
1444 path
, location
.objectid
);
1446 btrfs_inc_nlink(inode
);
1447 ret
= btrfs_unlink_inode(trans
, root
, dir
, inode
,
1453 /* there might still be more names under this key
1454 * check and repeat if required
1456 ret
= btrfs_search_slot(NULL
, root
, dir_key
, path
,
1463 btrfs_release_path(log
, log_path
);
1466 ptr
= (unsigned long)(di
+ 1);
1471 btrfs_release_path(root
, path
);
1472 btrfs_release_path(log
, log_path
);
1477 * deletion replay happens before we copy any new directory items
1478 * out of the log or out of backreferences from inodes. It
1479 * scans the log to find ranges of keys that log is authoritative for,
1480 * and then scans the directory to find items in those ranges that are
1481 * not present in the log.
1483 * Anything we don't find in the log is unlinked and removed from the
1486 static noinline
int replay_dir_deletes(struct btrfs_trans_handle
*trans
,
1487 struct btrfs_root
*root
,
1488 struct btrfs_root
*log
,
1489 struct btrfs_path
*path
,
1494 int key_type
= BTRFS_DIR_LOG_ITEM_KEY
;
1496 struct btrfs_key dir_key
;
1497 struct btrfs_key found_key
;
1498 struct btrfs_path
*log_path
;
1501 dir_key
.objectid
= dirid
;
1502 dir_key
.type
= BTRFS_DIR_ITEM_KEY
;
1503 log_path
= btrfs_alloc_path();
1507 dir
= read_one_inode(root
, dirid
);
1508 /* it isn't an error if the inode isn't there, that can happen
1509 * because we replay the deletes before we copy in the inode item
1513 btrfs_free_path(log_path
);
1520 ret
= find_dir_range(log
, path
, dirid
, key_type
,
1521 &range_start
, &range_end
);
1525 dir_key
.offset
= range_start
;
1528 ret
= btrfs_search_slot(NULL
, root
, &dir_key
, path
,
1533 nritems
= btrfs_header_nritems(path
->nodes
[0]);
1534 if (path
->slots
[0] >= nritems
) {
1535 ret
= btrfs_next_leaf(root
, path
);
1539 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
,
1541 if (found_key
.objectid
!= dirid
||
1542 found_key
.type
!= dir_key
.type
)
1545 if (found_key
.offset
> range_end
)
1548 ret
= check_item_in_log(trans
, root
, log
, path
,
1549 log_path
, dir
, &found_key
);
1551 if (found_key
.offset
== (u64
)-1)
1553 dir_key
.offset
= found_key
.offset
+ 1;
1555 btrfs_release_path(root
, path
);
1556 if (range_end
== (u64
)-1)
1558 range_start
= range_end
+ 1;
1563 if (key_type
== BTRFS_DIR_LOG_ITEM_KEY
) {
1564 key_type
= BTRFS_DIR_LOG_INDEX_KEY
;
1565 dir_key
.type
= BTRFS_DIR_INDEX_KEY
;
1566 btrfs_release_path(root
, path
);
1570 btrfs_release_path(root
, path
);
1571 btrfs_free_path(log_path
);
1577 * the process_func used to replay items from the log tree. This
1578 * gets called in two different stages. The first stage just looks
1579 * for inodes and makes sure they are all copied into the subvolume.
1581 * The second stage copies all the other item types from the log into
1582 * the subvolume. The two stage approach is slower, but gets rid of
1583 * lots of complexity around inodes referencing other inodes that exist
1584 * only in the log (references come from either directory items or inode
1587 static int replay_one_buffer(struct btrfs_root
*log
, struct extent_buffer
*eb
,
1588 struct walk_control
*wc
, u64 gen
)
1591 struct btrfs_path
*path
;
1592 struct btrfs_root
*root
= wc
->replay_dest
;
1593 struct btrfs_key key
;
1599 btrfs_read_buffer(eb
, gen
);
1601 level
= btrfs_header_level(eb
);
1606 path
= btrfs_alloc_path();
1609 nritems
= btrfs_header_nritems(eb
);
1610 for (i
= 0; i
< nritems
; i
++) {
1611 btrfs_item_key_to_cpu(eb
, &key
, i
);
1612 item_size
= btrfs_item_size_nr(eb
, i
);
1614 /* inode keys are done during the first stage */
1615 if (key
.type
== BTRFS_INODE_ITEM_KEY
&&
1616 wc
->stage
== LOG_WALK_REPLAY_INODES
) {
1617 struct inode
*inode
;
1618 struct btrfs_inode_item
*inode_item
;
1621 inode_item
= btrfs_item_ptr(eb
, i
,
1622 struct btrfs_inode_item
);
1623 mode
= btrfs_inode_mode(eb
, inode_item
);
1624 if (S_ISDIR(mode
)) {
1625 ret
= replay_dir_deletes(wc
->trans
,
1626 root
, log
, path
, key
.objectid
);
1629 ret
= overwrite_item(wc
->trans
, root
, path
,
1633 /* for regular files, truncate away
1634 * extents past the new EOF
1636 if (S_ISREG(mode
)) {
1637 inode
= read_one_inode(root
,
1641 ret
= btrfs_truncate_inode_items(wc
->trans
,
1642 root
, inode
, inode
->i_size
,
1643 BTRFS_EXTENT_DATA_KEY
);
1647 ret
= link_to_fixup_dir(wc
->trans
, root
,
1648 path
, key
.objectid
);
1651 if (wc
->stage
< LOG_WALK_REPLAY_ALL
)
1654 /* these keys are simply copied */
1655 if (key
.type
== BTRFS_XATTR_ITEM_KEY
) {
1656 ret
= overwrite_item(wc
->trans
, root
, path
,
1659 } else if (key
.type
== BTRFS_INODE_REF_KEY
) {
1660 ret
= add_inode_ref(wc
->trans
, root
, log
, path
,
1662 BUG_ON(ret
&& ret
!= -ENOENT
);
1663 } else if (key
.type
== BTRFS_EXTENT_DATA_KEY
) {
1664 ret
= replay_one_extent(wc
->trans
, root
, path
,
1667 } else if (key
.type
== BTRFS_CSUM_ITEM_KEY
) {
1668 ret
= replay_one_csum(wc
->trans
, root
, path
,
1671 } else if (key
.type
== BTRFS_DIR_ITEM_KEY
||
1672 key
.type
== BTRFS_DIR_INDEX_KEY
) {
1673 ret
= replay_one_dir_item(wc
->trans
, root
, path
,
1678 btrfs_free_path(path
);
1682 static int noinline
walk_down_log_tree(struct btrfs_trans_handle
*trans
,
1683 struct btrfs_root
*root
,
1684 struct btrfs_path
*path
, int *level
,
1685 struct walk_control
*wc
)
1691 struct extent_buffer
*next
;
1692 struct extent_buffer
*cur
;
1693 struct extent_buffer
*parent
;
1697 WARN_ON(*level
< 0);
1698 WARN_ON(*level
>= BTRFS_MAX_LEVEL
);
1701 WARN_ON(*level
< 0);
1702 WARN_ON(*level
>= BTRFS_MAX_LEVEL
);
1703 cur
= path
->nodes
[*level
];
1705 if (btrfs_header_level(cur
) != *level
)
1708 if (path
->slots
[*level
] >=
1709 btrfs_header_nritems(cur
))
1712 bytenr
= btrfs_node_blockptr(cur
, path
->slots
[*level
]);
1713 ptr_gen
= btrfs_node_ptr_generation(cur
, path
->slots
[*level
]);
1714 blocksize
= btrfs_level_size(root
, *level
- 1);
1716 parent
= path
->nodes
[*level
];
1717 root_owner
= btrfs_header_owner(parent
);
1718 root_gen
= btrfs_header_generation(parent
);
1720 next
= btrfs_find_create_tree_block(root
, bytenr
, blocksize
);
1722 wc
->process_func(root
, next
, wc
, ptr_gen
);
1725 path
->slots
[*level
]++;
1727 btrfs_read_buffer(next
, ptr_gen
);
1729 btrfs_tree_lock(next
);
1730 clean_tree_block(trans
, root
, next
);
1731 btrfs_wait_tree_block_writeback(next
);
1732 btrfs_tree_unlock(next
);
1734 ret
= btrfs_drop_leaf_ref(trans
, root
, next
);
1737 WARN_ON(root_owner
!=
1738 BTRFS_TREE_LOG_OBJECTID
);
1739 ret
= btrfs_free_reserved_extent(root
,
1743 free_extent_buffer(next
);
1746 btrfs_read_buffer(next
, ptr_gen
);
1748 WARN_ON(*level
<= 0);
1749 if (path
->nodes
[*level
-1])
1750 free_extent_buffer(path
->nodes
[*level
-1]);
1751 path
->nodes
[*level
-1] = next
;
1752 *level
= btrfs_header_level(next
);
1753 path
->slots
[*level
] = 0;
1756 WARN_ON(*level
< 0);
1757 WARN_ON(*level
>= BTRFS_MAX_LEVEL
);
1759 if (path
->nodes
[*level
] == root
->node
) {
1760 parent
= path
->nodes
[*level
];
1762 parent
= path
->nodes
[*level
+ 1];
1764 bytenr
= path
->nodes
[*level
]->start
;
1766 blocksize
= btrfs_level_size(root
, *level
);
1767 root_owner
= btrfs_header_owner(parent
);
1768 root_gen
= btrfs_header_generation(parent
);
1770 wc
->process_func(root
, path
->nodes
[*level
], wc
,
1771 btrfs_header_generation(path
->nodes
[*level
]));
1774 next
= path
->nodes
[*level
];
1775 btrfs_tree_lock(next
);
1776 clean_tree_block(trans
, root
, next
);
1777 btrfs_wait_tree_block_writeback(next
);
1778 btrfs_tree_unlock(next
);
1781 ret
= btrfs_drop_leaf_ref(trans
, root
, next
);
1784 WARN_ON(root_owner
!= BTRFS_TREE_LOG_OBJECTID
);
1785 ret
= btrfs_free_reserved_extent(root
, bytenr
, blocksize
);
1788 free_extent_buffer(path
->nodes
[*level
]);
1789 path
->nodes
[*level
] = NULL
;
1796 static int noinline
walk_up_log_tree(struct btrfs_trans_handle
*trans
,
1797 struct btrfs_root
*root
,
1798 struct btrfs_path
*path
, int *level
,
1799 struct walk_control
*wc
)
1807 for(i
= *level
; i
< BTRFS_MAX_LEVEL
- 1 && path
->nodes
[i
]; i
++) {
1808 slot
= path
->slots
[i
];
1809 if (slot
< btrfs_header_nritems(path
->nodes
[i
]) - 1) {
1810 struct extent_buffer
*node
;
1811 node
= path
->nodes
[i
];
1814 WARN_ON(*level
== 0);
1817 struct extent_buffer
*parent
;
1818 if (path
->nodes
[*level
] == root
->node
)
1819 parent
= path
->nodes
[*level
];
1821 parent
= path
->nodes
[*level
+ 1];
1823 root_owner
= btrfs_header_owner(parent
);
1824 root_gen
= btrfs_header_generation(parent
);
1825 wc
->process_func(root
, path
->nodes
[*level
], wc
,
1826 btrfs_header_generation(path
->nodes
[*level
]));
1828 struct extent_buffer
*next
;
1830 next
= path
->nodes
[*level
];
1832 btrfs_tree_lock(next
);
1833 clean_tree_block(trans
, root
, next
);
1834 btrfs_wait_tree_block_writeback(next
);
1835 btrfs_tree_unlock(next
);
1838 ret
= btrfs_drop_leaf_ref(trans
, root
,
1843 WARN_ON(root_owner
!= BTRFS_TREE_LOG_OBJECTID
);
1844 ret
= btrfs_free_reserved_extent(root
,
1845 path
->nodes
[*level
]->start
,
1846 path
->nodes
[*level
]->len
);
1849 free_extent_buffer(path
->nodes
[*level
]);
1850 path
->nodes
[*level
] = NULL
;
1858 * drop the reference count on the tree rooted at 'snap'. This traverses
1859 * the tree freeing any blocks that have a ref count of zero after being
1862 static int walk_log_tree(struct btrfs_trans_handle
*trans
,
1863 struct btrfs_root
*log
, struct walk_control
*wc
)
1868 struct btrfs_path
*path
;
1872 path
= btrfs_alloc_path();
1875 level
= btrfs_header_level(log
->node
);
1877 path
->nodes
[level
] = log
->node
;
1878 extent_buffer_get(log
->node
);
1879 path
->slots
[level
] = 0;
1882 wret
= walk_down_log_tree(trans
, log
, path
, &level
, wc
);
1888 wret
= walk_up_log_tree(trans
, log
, path
, &level
, wc
);
1895 /* was the root node processed? if not, catch it here */
1896 if (path
->nodes
[orig_level
]) {
1897 wc
->process_func(log
, path
->nodes
[orig_level
], wc
,
1898 btrfs_header_generation(path
->nodes
[orig_level
]));
1900 struct extent_buffer
*next
;
1902 next
= path
->nodes
[orig_level
];
1904 btrfs_tree_lock(next
);
1905 clean_tree_block(trans
, log
, next
);
1906 btrfs_wait_tree_block_writeback(next
);
1907 btrfs_tree_unlock(next
);
1909 if (orig_level
== 0) {
1910 ret
= btrfs_drop_leaf_ref(trans
, log
,
1914 WARN_ON(log
->root_key
.objectid
!=
1915 BTRFS_TREE_LOG_OBJECTID
);
1916 ret
= btrfs_free_reserved_extent(log
, next
->start
,
1922 for (i
= 0; i
<= orig_level
; i
++) {
1923 if (path
->nodes
[i
]) {
1924 free_extent_buffer(path
->nodes
[i
]);
1925 path
->nodes
[i
] = NULL
;
1928 btrfs_free_path(path
);
1930 free_extent_buffer(log
->node
);
1934 int wait_log_commit(struct btrfs_root
*log
)
1937 u64 transid
= log
->fs_info
->tree_log_transid
;
1940 prepare_to_wait(&log
->fs_info
->tree_log_wait
, &wait
,
1941 TASK_UNINTERRUPTIBLE
);
1942 mutex_unlock(&log
->fs_info
->tree_log_mutex
);
1943 if (atomic_read(&log
->fs_info
->tree_log_commit
))
1945 finish_wait(&log
->fs_info
->tree_log_wait
, &wait
);
1946 mutex_lock(&log
->fs_info
->tree_log_mutex
);
1947 } while(transid
== log
->fs_info
->tree_log_transid
&&
1948 atomic_read(&log
->fs_info
->tree_log_commit
));
1953 * btrfs_sync_log does sends a given tree log down to the disk and
1954 * updates the super blocks to record it. When this call is done,
1955 * you know that any inodes previously logged are safely on disk
1957 int btrfs_sync_log(struct btrfs_trans_handle
*trans
,
1958 struct btrfs_root
*root
)
1961 unsigned long batch
;
1962 struct btrfs_root
*log
= root
->log_root
;
1964 mutex_lock(&log
->fs_info
->tree_log_mutex
);
1965 if (atomic_read(&log
->fs_info
->tree_log_commit
)) {
1966 wait_log_commit(log
);
1969 atomic_set(&log
->fs_info
->tree_log_commit
, 1);
1972 batch
= log
->fs_info
->tree_log_batch
;
1973 mutex_unlock(&log
->fs_info
->tree_log_mutex
);
1974 schedule_timeout_uninterruptible(1);
1975 mutex_lock(&log
->fs_info
->tree_log_mutex
);
1977 while(atomic_read(&log
->fs_info
->tree_log_writers
)) {
1979 prepare_to_wait(&log
->fs_info
->tree_log_wait
, &wait
,
1980 TASK_UNINTERRUPTIBLE
);
1981 mutex_unlock(&log
->fs_info
->tree_log_mutex
);
1982 if (atomic_read(&log
->fs_info
->tree_log_writers
))
1984 mutex_lock(&log
->fs_info
->tree_log_mutex
);
1985 finish_wait(&log
->fs_info
->tree_log_wait
, &wait
);
1987 if (batch
== log
->fs_info
->tree_log_batch
)
1991 ret
= btrfs_write_and_wait_marked_extents(log
, &log
->dirty_log_pages
);
1993 ret
= btrfs_write_and_wait_marked_extents(root
->fs_info
->log_root_tree
,
1994 &root
->fs_info
->log_root_tree
->dirty_log_pages
);
1997 btrfs_set_super_log_root(&root
->fs_info
->super_for_commit
,
1998 log
->fs_info
->log_root_tree
->node
->start
);
1999 btrfs_set_super_log_root_level(&root
->fs_info
->super_for_commit
,
2000 btrfs_header_level(log
->fs_info
->log_root_tree
->node
));
2002 write_ctree_super(trans
, log
->fs_info
->tree_root
);
2003 log
->fs_info
->tree_log_transid
++;
2004 log
->fs_info
->tree_log_batch
= 0;
2005 atomic_set(&log
->fs_info
->tree_log_commit
, 0);
2007 if (waitqueue_active(&log
->fs_info
->tree_log_wait
))
2008 wake_up(&log
->fs_info
->tree_log_wait
);
2010 mutex_unlock(&log
->fs_info
->tree_log_mutex
);
2015 /* * free all the extents used by the tree log. This should be called
2016 * at commit time of the full transaction
2018 int btrfs_free_log(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
)
2021 struct btrfs_root
*log
;
2025 struct walk_control wc
= {
2027 .process_func
= process_one_buffer
2030 if (!root
->log_root
)
2033 log
= root
->log_root
;
2034 ret
= walk_log_tree(trans
, log
, &wc
);
2038 ret
= find_first_extent_bit(&log
->dirty_log_pages
,
2039 0, &start
, &end
, EXTENT_DIRTY
);
2043 clear_extent_dirty(&log
->dirty_log_pages
,
2044 start
, end
, GFP_NOFS
);
2047 log
= root
->log_root
;
2048 ret
= btrfs_del_root(trans
, root
->fs_info
->log_root_tree
,
2051 root
->log_root
= NULL
;
2052 kfree(root
->log_root
);
2057 * helper function to update the item for a given subvolumes log root
2058 * in the tree of log roots
2060 static int update_log_root(struct btrfs_trans_handle
*trans
,
2061 struct btrfs_root
*log
)
2063 u64 bytenr
= btrfs_root_bytenr(&log
->root_item
);
2066 if (log
->node
->start
== bytenr
)
2069 btrfs_set_root_bytenr(&log
->root_item
, log
->node
->start
);
2070 btrfs_set_root_level(&log
->root_item
, btrfs_header_level(log
->node
));
2071 ret
= btrfs_update_root(trans
, log
->fs_info
->log_root_tree
,
2072 &log
->root_key
, &log
->root_item
);
2078 * If both a file and directory are logged, and unlinks or renames are
2079 * mixed in, we have a few interesting corners:
2081 * create file X in dir Y
2082 * link file X to X.link in dir Y
2084 * unlink file X but leave X.link
2087 * After a crash we would expect only X.link to exist. But file X
2088 * didn't get fsync'd again so the log has back refs for X and X.link.
2090 * We solve this by removing directory entries and inode backrefs from the
2091 * log when a file that was logged in the current transaction is
2092 * unlinked. Any later fsync will include the updated log entries, and
2093 * we'll be able to reconstruct the proper directory items from backrefs.
2095 * This optimizations allows us to avoid relogging the entire inode
2096 * or the entire directory.
2098 int btrfs_del_dir_entries_in_log(struct btrfs_trans_handle
*trans
,
2099 struct btrfs_root
*root
,
2100 const char *name
, int name_len
,
2101 struct inode
*dir
, u64 index
)
2103 struct btrfs_root
*log
;
2104 struct btrfs_dir_item
*di
;
2105 struct btrfs_path
*path
;
2109 if (BTRFS_I(dir
)->logged_trans
< trans
->transid
)
2112 ret
= join_running_log_trans(root
);
2116 mutex_lock(&BTRFS_I(dir
)->log_mutex
);
2118 log
= root
->log_root
;
2119 path
= btrfs_alloc_path();
2120 di
= btrfs_lookup_dir_item(trans
, log
, path
, dir
->i_ino
,
2121 name
, name_len
, -1);
2122 if (di
&& !IS_ERR(di
)) {
2123 ret
= btrfs_delete_one_dir_name(trans
, log
, path
, di
);
2124 bytes_del
+= name_len
;
2127 btrfs_release_path(log
, path
);
2128 di
= btrfs_lookup_dir_index_item(trans
, log
, path
, dir
->i_ino
,
2129 index
, name
, name_len
, -1);
2130 if (di
&& !IS_ERR(di
)) {
2131 ret
= btrfs_delete_one_dir_name(trans
, log
, path
, di
);
2132 bytes_del
+= name_len
;
2136 /* update the directory size in the log to reflect the names
2140 struct btrfs_key key
;
2142 key
.objectid
= dir
->i_ino
;
2144 key
.type
= BTRFS_INODE_ITEM_KEY
;
2145 btrfs_release_path(log
, path
);
2147 ret
= btrfs_search_slot(trans
, log
, &key
, path
, 0, 1);
2149 struct btrfs_inode_item
*item
;
2152 item
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
2153 struct btrfs_inode_item
);
2154 i_size
= btrfs_inode_size(path
->nodes
[0], item
);
2155 if (i_size
> bytes_del
)
2156 i_size
-= bytes_del
;
2159 btrfs_set_inode_size(path
->nodes
[0], item
, i_size
);
2160 btrfs_mark_buffer_dirty(path
->nodes
[0]);
2163 btrfs_release_path(log
, path
);
2166 btrfs_free_path(path
);
2167 mutex_unlock(&BTRFS_I(dir
)->log_mutex
);
2168 end_log_trans(root
);
2173 /* see comments for btrfs_del_dir_entries_in_log */
2174 int btrfs_del_inode_ref_in_log(struct btrfs_trans_handle
*trans
,
2175 struct btrfs_root
*root
,
2176 const char *name
, int name_len
,
2177 struct inode
*inode
, u64 dirid
)
2179 struct btrfs_root
*log
;
2183 if (BTRFS_I(inode
)->logged_trans
< trans
->transid
)
2186 ret
= join_running_log_trans(root
);
2189 log
= root
->log_root
;
2190 mutex_lock(&BTRFS_I(inode
)->log_mutex
);
2192 ret
= btrfs_del_inode_ref(trans
, log
, name
, name_len
, inode
->i_ino
,
2194 mutex_unlock(&BTRFS_I(inode
)->log_mutex
);
2195 end_log_trans(root
);
2201 * creates a range item in the log for 'dirid'. first_offset and
2202 * last_offset tell us which parts of the key space the log should
2203 * be considered authoritative for.
2205 static noinline
int insert_dir_log_key(struct btrfs_trans_handle
*trans
,
2206 struct btrfs_root
*log
,
2207 struct btrfs_path
*path
,
2208 int key_type
, u64 dirid
,
2209 u64 first_offset
, u64 last_offset
)
2212 struct btrfs_key key
;
2213 struct btrfs_dir_log_item
*item
;
2215 key
.objectid
= dirid
;
2216 key
.offset
= first_offset
;
2217 if (key_type
== BTRFS_DIR_ITEM_KEY
)
2218 key
.type
= BTRFS_DIR_LOG_ITEM_KEY
;
2220 key
.type
= BTRFS_DIR_LOG_INDEX_KEY
;
2221 ret
= btrfs_insert_empty_item(trans
, log
, path
, &key
, sizeof(*item
));
2224 item
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
2225 struct btrfs_dir_log_item
);
2226 btrfs_set_dir_log_end(path
->nodes
[0], item
, last_offset
);
2227 btrfs_mark_buffer_dirty(path
->nodes
[0]);
2228 btrfs_release_path(log
, path
);
2233 * log all the items included in the current transaction for a given
2234 * directory. This also creates the range items in the log tree required
2235 * to replay anything deleted before the fsync
2237 static noinline
int log_dir_items(struct btrfs_trans_handle
*trans
,
2238 struct btrfs_root
*root
, struct inode
*inode
,
2239 struct btrfs_path
*path
,
2240 struct btrfs_path
*dst_path
, int key_type
,
2241 u64 min_offset
, u64
*last_offset_ret
)
2243 struct btrfs_key min_key
;
2244 struct btrfs_key max_key
;
2245 struct btrfs_root
*log
= root
->log_root
;
2246 struct extent_buffer
*src
;
2250 u64 first_offset
= min_offset
;
2251 u64 last_offset
= (u64
)-1;
2253 log
= root
->log_root
;
2254 max_key
.objectid
= inode
->i_ino
;
2255 max_key
.offset
= (u64
)-1;
2256 max_key
.type
= key_type
;
2258 min_key
.objectid
= inode
->i_ino
;
2259 min_key
.type
= key_type
;
2260 min_key
.offset
= min_offset
;
2262 path
->keep_locks
= 1;
2264 ret
= btrfs_search_forward(root
, &min_key
, &max_key
,
2265 path
, 0, trans
->transid
);
2268 * we didn't find anything from this transaction, see if there
2269 * is anything at all
2271 if (ret
!= 0 || min_key
.objectid
!= inode
->i_ino
||
2272 min_key
.type
!= key_type
) {
2273 min_key
.objectid
= inode
->i_ino
;
2274 min_key
.type
= key_type
;
2275 min_key
.offset
= (u64
)-1;
2276 btrfs_release_path(root
, path
);
2277 ret
= btrfs_search_slot(NULL
, root
, &min_key
, path
, 0, 0);
2279 btrfs_release_path(root
, path
);
2282 ret
= btrfs_previous_item(root
, path
, inode
->i_ino
, key_type
);
2284 /* if ret == 0 there are items for this type,
2285 * create a range to tell us the last key of this type.
2286 * otherwise, there are no items in this directory after
2287 * *min_offset, and we create a range to indicate that.
2290 struct btrfs_key tmp
;
2291 btrfs_item_key_to_cpu(path
->nodes
[0], &tmp
,
2293 if (key_type
== tmp
.type
) {
2294 first_offset
= max(min_offset
, tmp
.offset
) + 1;
2300 /* go backward to find any previous key */
2301 ret
= btrfs_previous_item(root
, path
, inode
->i_ino
, key_type
);
2303 struct btrfs_key tmp
;
2304 btrfs_item_key_to_cpu(path
->nodes
[0], &tmp
, path
->slots
[0]);
2305 if (key_type
== tmp
.type
) {
2306 first_offset
= tmp
.offset
;
2307 ret
= overwrite_item(trans
, log
, dst_path
,
2308 path
->nodes
[0], path
->slots
[0],
2312 btrfs_release_path(root
, path
);
2314 /* find the first key from this transaction again */
2315 ret
= btrfs_search_slot(NULL
, root
, &min_key
, path
, 0, 0);
2322 * we have a block from this transaction, log every item in it
2323 * from our directory
2326 struct btrfs_key tmp
;
2327 src
= path
->nodes
[0];
2328 nritems
= btrfs_header_nritems(src
);
2329 for (i
= path
->slots
[0]; i
< nritems
; i
++) {
2330 btrfs_item_key_to_cpu(src
, &min_key
, i
);
2332 if (min_key
.objectid
!= inode
->i_ino
||
2333 min_key
.type
!= key_type
)
2335 ret
= overwrite_item(trans
, log
, dst_path
, src
, i
,
2339 path
->slots
[0] = nritems
;
2342 * look ahead to the next item and see if it is also
2343 * from this directory and from this transaction
2345 ret
= btrfs_next_leaf(root
, path
);
2347 last_offset
= (u64
)-1;
2350 btrfs_item_key_to_cpu(path
->nodes
[0], &tmp
, path
->slots
[0]);
2351 if (tmp
.objectid
!= inode
->i_ino
|| tmp
.type
!= key_type
) {
2352 last_offset
= (u64
)-1;
2355 if (btrfs_header_generation(path
->nodes
[0]) != trans
->transid
) {
2356 ret
= overwrite_item(trans
, log
, dst_path
,
2357 path
->nodes
[0], path
->slots
[0],
2361 last_offset
= tmp
.offset
;
2366 *last_offset_ret
= last_offset
;
2367 btrfs_release_path(root
, path
);
2368 btrfs_release_path(log
, dst_path
);
2370 /* insert the log range keys to indicate where the log is valid */
2371 ret
= insert_dir_log_key(trans
, log
, path
, key_type
, inode
->i_ino
,
2372 first_offset
, last_offset
);
2378 * logging directories is very similar to logging inodes, We find all the items
2379 * from the current transaction and write them to the log.
2381 * The recovery code scans the directory in the subvolume, and if it finds a
2382 * key in the range logged that is not present in the log tree, then it means
2383 * that dir entry was unlinked during the transaction.
2385 * In order for that scan to work, we must include one key smaller than
2386 * the smallest logged by this transaction and one key larger than the largest
2387 * key logged by this transaction.
2389 static noinline
int log_directory_changes(struct btrfs_trans_handle
*trans
,
2390 struct btrfs_root
*root
, struct inode
*inode
,
2391 struct btrfs_path
*path
,
2392 struct btrfs_path
*dst_path
)
2397 int key_type
= BTRFS_DIR_ITEM_KEY
;
2403 ret
= log_dir_items(trans
, root
, inode
, path
,
2404 dst_path
, key_type
, min_key
,
2407 if (max_key
== (u64
)-1)
2409 min_key
= max_key
+ 1;
2412 if (key_type
== BTRFS_DIR_ITEM_KEY
) {
2413 key_type
= BTRFS_DIR_INDEX_KEY
;
2420 * a helper function to drop items from the log before we relog an
2421 * inode. max_key_type indicates the highest item type to remove.
2422 * This cannot be run for file data extents because it does not
2423 * free the extents they point to.
2425 static int drop_objectid_items(struct btrfs_trans_handle
*trans
,
2426 struct btrfs_root
*log
,
2427 struct btrfs_path
*path
,
2428 u64 objectid
, int max_key_type
)
2431 struct btrfs_key key
;
2432 struct btrfs_key found_key
;
2434 key
.objectid
= objectid
;
2435 key
.type
= max_key_type
;
2436 key
.offset
= (u64
)-1;
2439 ret
= btrfs_search_slot(trans
, log
, &key
, path
, -1, 1);
2444 if (path
->slots
[0] == 0)
2448 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
,
2451 if (found_key
.objectid
!= objectid
)
2454 ret
= btrfs_del_item(trans
, log
, path
);
2456 btrfs_release_path(log
, path
);
2458 btrfs_release_path(log
, path
);
2462 static noinline
int copy_items(struct btrfs_trans_handle
*trans
,
2463 struct btrfs_root
*log
,
2464 struct btrfs_path
*dst_path
,
2465 struct extent_buffer
*src
,
2466 int start_slot
, int nr
, int inode_only
)
2468 unsigned long src_offset
;
2469 unsigned long dst_offset
;
2470 struct btrfs_file_extent_item
*extent
;
2471 struct btrfs_inode_item
*inode_item
;
2473 struct btrfs_key
*ins_keys
;
2478 ins_data
= kmalloc(nr
* sizeof(struct btrfs_key
) +
2479 nr
* sizeof(u32
), GFP_NOFS
);
2480 ins_sizes
= (u32
*)ins_data
;
2481 ins_keys
= (struct btrfs_key
*)(ins_data
+ nr
* sizeof(u32
));
2483 for (i
= 0; i
< nr
; i
++) {
2484 ins_sizes
[i
] = btrfs_item_size_nr(src
, i
+ start_slot
);
2485 btrfs_item_key_to_cpu(src
, ins_keys
+ i
, i
+ start_slot
);
2487 ret
= btrfs_insert_empty_items(trans
, log
, dst_path
,
2488 ins_keys
, ins_sizes
, nr
);
2491 for (i
= 0; i
< nr
; i
++) {
2492 dst_offset
= btrfs_item_ptr_offset(dst_path
->nodes
[0],
2493 dst_path
->slots
[0]);
2495 src_offset
= btrfs_item_ptr_offset(src
, start_slot
+ i
);
2497 copy_extent_buffer(dst_path
->nodes
[0], src
, dst_offset
,
2498 src_offset
, ins_sizes
[i
]);
2500 if (inode_only
== LOG_INODE_EXISTS
&&
2501 ins_keys
[i
].type
== BTRFS_INODE_ITEM_KEY
) {
2502 inode_item
= btrfs_item_ptr(dst_path
->nodes
[0],
2504 struct btrfs_inode_item
);
2505 btrfs_set_inode_size(dst_path
->nodes
[0], inode_item
, 0);
2507 /* set the generation to zero so the recover code
2508 * can tell the difference between an logging
2509 * just to say 'this inode exists' and a logging
2510 * to say 'update this inode with these values'
2512 btrfs_set_inode_generation(dst_path
->nodes
[0],
2515 /* take a reference on file data extents so that truncates
2516 * or deletes of this inode don't have to relog the inode
2519 if (btrfs_key_type(ins_keys
+ i
) == BTRFS_EXTENT_DATA_KEY
) {
2521 extent
= btrfs_item_ptr(src
, start_slot
+ i
,
2522 struct btrfs_file_extent_item
);
2524 found_type
= btrfs_file_extent_type(src
, extent
);
2525 if (found_type
== BTRFS_FILE_EXTENT_REG
) {
2526 u64 ds
= btrfs_file_extent_disk_bytenr(src
,
2528 u64 dl
= btrfs_file_extent_disk_num_bytes(src
,
2530 /* ds == 0 is a hole */
2532 ret
= btrfs_inc_extent_ref(trans
, log
,
2534 dst_path
->nodes
[0]->start
,
2535 BTRFS_TREE_LOG_OBJECTID
,
2537 ins_keys
[i
].objectid
,
2538 ins_keys
[i
].offset
);
2543 dst_path
->slots
[0]++;
2546 btrfs_mark_buffer_dirty(dst_path
->nodes
[0]);
2547 btrfs_release_path(log
, dst_path
);
2552 /* log a single inode in the tree log.
2553 * At least one parent directory for this inode must exist in the tree
2554 * or be logged already.
2556 * Any items from this inode changed by the current transaction are copied
2557 * to the log tree. An extra reference is taken on any extents in this
2558 * file, allowing us to avoid a whole pile of corner cases around logging
2559 * blocks that have been removed from the tree.
2561 * See LOG_INODE_ALL and related defines for a description of what inode_only
2564 * This handles both files and directories.
2566 static int __btrfs_log_inode(struct btrfs_trans_handle
*trans
,
2567 struct btrfs_root
*root
, struct inode
*inode
,
2570 struct btrfs_path
*path
;
2571 struct btrfs_path
*dst_path
;
2572 struct btrfs_key min_key
;
2573 struct btrfs_key max_key
;
2574 struct btrfs_root
*log
= root
->log_root
;
2575 struct extent_buffer
*src
= NULL
;
2579 int ins_start_slot
= 0;
2582 log
= root
->log_root
;
2584 path
= btrfs_alloc_path();
2585 dst_path
= btrfs_alloc_path();
2587 min_key
.objectid
= inode
->i_ino
;
2588 min_key
.type
= BTRFS_INODE_ITEM_KEY
;
2591 max_key
.objectid
= inode
->i_ino
;
2592 if (inode_only
== LOG_INODE_EXISTS
|| S_ISDIR(inode
->i_mode
))
2593 max_key
.type
= BTRFS_XATTR_ITEM_KEY
;
2595 max_key
.type
= (u8
)-1;
2596 max_key
.offset
= (u64
)-1;
2599 * if this inode has already been logged and we're in inode_only
2600 * mode, we don't want to delete the things that have already
2601 * been written to the log.
2603 * But, if the inode has been through an inode_only log,
2604 * the logged_trans field is not set. This allows us to catch
2605 * any new names for this inode in the backrefs by logging it
2608 if (inode_only
== LOG_INODE_EXISTS
&&
2609 BTRFS_I(inode
)->logged_trans
== trans
->transid
) {
2610 btrfs_free_path(path
);
2611 btrfs_free_path(dst_path
);
2614 mutex_lock(&BTRFS_I(inode
)->log_mutex
);
2617 * a brute force approach to making sure we get the most uptodate
2618 * copies of everything.
2620 if (S_ISDIR(inode
->i_mode
)) {
2621 int max_key_type
= BTRFS_DIR_LOG_INDEX_KEY
;
2623 if (inode_only
== LOG_INODE_EXISTS
)
2624 max_key_type
= BTRFS_XATTR_ITEM_KEY
;
2625 ret
= drop_objectid_items(trans
, log
, path
,
2626 inode
->i_ino
, max_key_type
);
2628 ret
= btrfs_truncate_inode_items(trans
, log
, inode
, 0, 0);
2631 path
->keep_locks
= 1;
2635 ret
= btrfs_search_forward(root
, &min_key
, &max_key
,
2636 path
, 0, trans
->transid
);
2640 /* note, ins_nr might be > 0 here, cleanup outside the loop */
2641 if (min_key
.objectid
!= inode
->i_ino
)
2643 if (min_key
.type
> max_key
.type
)
2646 src
= path
->nodes
[0];
2647 size
= btrfs_item_size_nr(src
, path
->slots
[0]);
2648 if (ins_nr
&& ins_start_slot
+ ins_nr
== path
->slots
[0]) {
2651 } else if (!ins_nr
) {
2652 ins_start_slot
= path
->slots
[0];
2657 ret
= copy_items(trans
, log
, dst_path
, src
, ins_start_slot
,
2658 ins_nr
, inode_only
);
2661 ins_start_slot
= path
->slots
[0];
2664 nritems
= btrfs_header_nritems(path
->nodes
[0]);
2666 if (path
->slots
[0] < nritems
) {
2667 btrfs_item_key_to_cpu(path
->nodes
[0], &min_key
,
2672 ret
= copy_items(trans
, log
, dst_path
, src
,
2674 ins_nr
, inode_only
);
2678 btrfs_release_path(root
, path
);
2680 if (min_key
.offset
< (u64
)-1)
2682 else if (min_key
.type
< (u8
)-1)
2684 else if (min_key
.objectid
< (u64
)-1)
2690 ret
= copy_items(trans
, log
, dst_path
, src
,
2692 ins_nr
, inode_only
);
2697 if (inode_only
== LOG_INODE_ALL
&& S_ISDIR(inode
->i_mode
)) {
2698 btrfs_release_path(root
, path
);
2699 btrfs_release_path(log
, dst_path
);
2700 BTRFS_I(inode
)->log_dirty_trans
= 0;
2701 ret
= log_directory_changes(trans
, root
, inode
, path
, dst_path
);
2704 BTRFS_I(inode
)->logged_trans
= trans
->transid
;
2705 mutex_unlock(&BTRFS_I(inode
)->log_mutex
);
2707 btrfs_free_path(path
);
2708 btrfs_free_path(dst_path
);
2710 mutex_lock(&root
->fs_info
->tree_log_mutex
);
2711 ret
= update_log_root(trans
, log
);
2713 mutex_unlock(&root
->fs_info
->tree_log_mutex
);
2718 int btrfs_log_inode(struct btrfs_trans_handle
*trans
,
2719 struct btrfs_root
*root
, struct inode
*inode
,
2724 start_log_trans(trans
, root
);
2725 ret
= __btrfs_log_inode(trans
, root
, inode
, inode_only
);
2726 end_log_trans(root
);
2731 * helper function around btrfs_log_inode to make sure newly created
2732 * parent directories also end up in the log. A minimal inode and backref
2733 * only logging is done of any parent directories that are older than
2734 * the last committed transaction
2736 int btrfs_log_dentry(struct btrfs_trans_handle
*trans
,
2737 struct btrfs_root
*root
, struct dentry
*dentry
)
2739 int inode_only
= LOG_INODE_ALL
;
2740 struct super_block
*sb
;
2743 start_log_trans(trans
, root
);
2744 sb
= dentry
->d_inode
->i_sb
;
2746 ret
= __btrfs_log_inode(trans
, root
, dentry
->d_inode
,
2749 inode_only
= LOG_INODE_EXISTS
;
2751 dentry
= dentry
->d_parent
;
2752 if (!dentry
|| !dentry
->d_inode
|| sb
!= dentry
->d_inode
->i_sb
)
2755 if (BTRFS_I(dentry
->d_inode
)->generation
<=
2756 root
->fs_info
->last_trans_committed
)
2759 end_log_trans(root
);
2764 * it is not safe to log dentry if the chunk root has added new
2765 * chunks. This returns 0 if the dentry was logged, and 1 otherwise.
2766 * If this returns 1, you must commit the transaction to safely get your
2769 int btrfs_log_dentry_safe(struct btrfs_trans_handle
*trans
,
2770 struct btrfs_root
*root
, struct dentry
*dentry
)
2773 gen
= root
->fs_info
->last_trans_new_blockgroup
;
2774 if (gen
> root
->fs_info
->last_trans_committed
)
2777 return btrfs_log_dentry(trans
, root
, dentry
);
2781 * should be called during mount to recover any replay any log trees
2784 int btrfs_recover_log_trees(struct btrfs_root
*log_root_tree
)
2787 struct btrfs_path
*path
;
2788 struct btrfs_trans_handle
*trans
;
2789 struct btrfs_key key
;
2790 struct btrfs_key found_key
;
2791 struct btrfs_key tmp_key
;
2792 struct btrfs_root
*log
;
2793 struct btrfs_fs_info
*fs_info
= log_root_tree
->fs_info
;
2795 struct walk_control wc
= {
2796 .process_func
= process_one_buffer
,
2800 fs_info
->log_root_recovering
= 1;
2801 path
= btrfs_alloc_path();
2804 trans
= btrfs_start_transaction(fs_info
->tree_root
, 1);
2809 walk_log_tree(trans
, log_root_tree
, &wc
);
2812 key
.objectid
= BTRFS_TREE_LOG_OBJECTID
;
2813 key
.offset
= (u64
)-1;
2814 btrfs_set_key_type(&key
, BTRFS_ROOT_ITEM_KEY
);
2817 ret
= btrfs_search_slot(NULL
, log_root_tree
, &key
, path
, 0, 0);
2821 if (path
->slots
[0] == 0)
2825 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
,
2827 btrfs_release_path(log_root_tree
, path
);
2828 if (found_key
.objectid
!= BTRFS_TREE_LOG_OBJECTID
)
2831 log
= btrfs_read_fs_root_no_radix(log_root_tree
,
2836 tmp_key
.objectid
= found_key
.offset
;
2837 tmp_key
.type
= BTRFS_ROOT_ITEM_KEY
;
2838 tmp_key
.offset
= (u64
)-1;
2840 wc
.replay_dest
= btrfs_read_fs_root_no_name(fs_info
, &tmp_key
);
2842 BUG_ON(!wc
.replay_dest
);
2844 btrfs_record_root_in_trans(wc
.replay_dest
);
2845 ret
= walk_log_tree(trans
, log
, &wc
);
2848 if (wc
.stage
== LOG_WALK_REPLAY_ALL
) {
2849 ret
= fixup_inode_link_counts(trans
, wc
.replay_dest
,
2853 ret
= btrfs_find_highest_inode(wc
.replay_dest
, &highest_inode
);
2855 wc
.replay_dest
->highest_inode
= highest_inode
;
2856 wc
.replay_dest
->last_inode_alloc
= highest_inode
;
2859 key
.offset
= found_key
.offset
- 1;
2860 free_extent_buffer(log
->node
);
2863 if (found_key
.offset
== 0)
2866 btrfs_release_path(log_root_tree
, path
);
2868 /* step one is to pin it all, step two is to replay just inodes */
2871 wc
.process_func
= replay_one_buffer
;
2872 wc
.stage
= LOG_WALK_REPLAY_INODES
;
2875 /* step three is to replay everything */
2876 if (wc
.stage
< LOG_WALK_REPLAY_ALL
) {
2881 btrfs_free_path(path
);
2883 free_extent_buffer(log_root_tree
->node
);
2884 log_root_tree
->log_root
= NULL
;
2885 fs_info
->log_root_recovering
= 0;
2887 /* step 4: commit the transaction, which also unpins the blocks */
2888 btrfs_commit_transaction(trans
, fs_info
->tree_root
);
2890 kfree(log_root_tree
);