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->nbytes = cpu_to_le64(root->leafsize);
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,
463 trans->transid, key->objectid);
466 * insert the extent pointer in the extent
469 ret = btrfs_alloc_logged_extent(trans, root,
470 path->nodes[0]->start,
471 root->root_key.objectid,
472 trans->transid, key->objectid,
479 btrfs_mark_buffer_dirty(path->nodes[0]);
480 btrfs_release_path(root, path);
485 * simple helper to read an inode off the disk from a given root
486 * This can only be called for subvolume roots and not for the log
488 static noinline struct inode *read_one_inode(struct btrfs_root *root,
492 inode = btrfs_iget_locked(root->fs_info->sb, objectid, root);
493 if (inode->i_state & I_NEW) {
494 BTRFS_I(inode)->root = root;
495 BTRFS_I(inode)->location.objectid = objectid;
496 BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY;
497 BTRFS_I(inode)->location.offset = 0;
498 btrfs_read_locked_inode(inode);
499 unlock_new_inode(inode);
502 if (is_bad_inode(inode)) {
509 /* replays a single extent in 'eb' at 'slot' with 'key' into the
510 * subvolume 'root'. path is released on entry and should be released
513 * extents in the log tree have not been allocated out of the extent
514 * tree yet. So, this completes the allocation, taking a reference
515 * as required if the extent already exists or creating a new extent
516 * if it isn't in the extent allocation tree yet.
518 * The extent is inserted into the file, dropping any existing extents
519 * from the file that overlap the new one.
521 static noinline int replay_one_extent(struct btrfs_trans_handle *trans,
522 struct btrfs_root *root,
523 struct btrfs_path *path,
524 struct extent_buffer *eb, int slot,
525 struct btrfs_key *key)
528 u64 mask = root->sectorsize - 1;
531 u64 start = key->offset;
532 struct btrfs_file_extent_item *item;
533 struct inode *inode = NULL;
537 item = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
538 found_type = btrfs_file_extent_type(eb, item);
540 if (found_type == BTRFS_FILE_EXTENT_REG)
541 extent_end = start + btrfs_file_extent_num_bytes(eb, item);
542 else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
543 size = btrfs_file_extent_inline_len(eb, item);
544 extent_end = (start + size + mask) & ~mask;
550 inode = read_one_inode(root, key->objectid);
557 * first check to see if we already have this extent in the
558 * file. This must be done before the btrfs_drop_extents run
559 * so we don't try to drop this extent.
561 ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino,
564 if (ret == 0 && found_type == BTRFS_FILE_EXTENT_REG) {
565 struct btrfs_file_extent_item cmp1;
566 struct btrfs_file_extent_item cmp2;
567 struct btrfs_file_extent_item *existing;
568 struct extent_buffer *leaf;
570 leaf = path->nodes[0];
571 existing = btrfs_item_ptr(leaf, path->slots[0],
572 struct btrfs_file_extent_item);
574 read_extent_buffer(eb, &cmp1, (unsigned long)item,
576 read_extent_buffer(leaf, &cmp2, (unsigned long)existing,
580 * we already have a pointer to this exact extent,
581 * we don't have to do anything
583 if (memcmp(&cmp1, &cmp2, sizeof(cmp1)) == 0) {
584 btrfs_release_path(root, path);
588 btrfs_release_path(root, path);
590 /* drop any overlapping extents */
591 ret = btrfs_drop_extents(trans, root, inode,
592 start, extent_end, start, &alloc_hint);
595 /* insert the extent */
596 ret = overwrite_item(trans, root, path, eb, slot, key);
599 /* btrfs_drop_extents changes i_bytes & i_blocks, update it here */
600 inode_add_bytes(inode, extent_end - start);
601 btrfs_update_inode(trans, root, inode);
609 * when cleaning up conflicts between the directory names in the
610 * subvolume, directory names in the log and directory names in the
611 * inode back references, we may have to unlink inodes from directories.
613 * This is a helper function to do the unlink of a specific directory
616 static noinline int drop_one_dir_item(struct btrfs_trans_handle *trans,
617 struct btrfs_root *root,
618 struct btrfs_path *path,
620 struct btrfs_dir_item *di)
625 struct extent_buffer *leaf;
626 struct btrfs_key location;
629 leaf = path->nodes[0];
631 btrfs_dir_item_key_to_cpu(leaf, di, &location);
632 name_len = btrfs_dir_name_len(leaf, di);
633 name = kmalloc(name_len, GFP_NOFS);
634 read_extent_buffer(leaf, name, (unsigned long)(di + 1), name_len);
635 btrfs_release_path(root, path);
637 inode = read_one_inode(root, location.objectid);
640 btrfs_inc_nlink(inode);
641 ret = btrfs_unlink_inode(trans, root, dir, inode, name, name_len);
649 * helper function to see if a given name and sequence number found
650 * in an inode back reference are already in a directory and correctly
651 * point to this inode
653 static noinline int inode_in_dir(struct btrfs_root *root,
654 struct btrfs_path *path,
655 u64 dirid, u64 objectid, u64 index,
656 const char *name, int name_len)
658 struct btrfs_dir_item *di;
659 struct btrfs_key location;
662 di = btrfs_lookup_dir_index_item(NULL, root, path, dirid,
663 index, name, name_len, 0);
664 if (di && !IS_ERR(di)) {
665 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location);
666 if (location.objectid != objectid)
670 btrfs_release_path(root, path);
672 di = btrfs_lookup_dir_item(NULL, root, path, dirid, name, name_len, 0);
673 if (di && !IS_ERR(di)) {
674 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location);
675 if (location.objectid != objectid)
681 btrfs_release_path(root, path);
686 * helper function to check a log tree for a named back reference in
687 * an inode. This is used to decide if a back reference that is
688 * found in the subvolume conflicts with what we find in the log.
690 * inode backreferences may have multiple refs in a single item,
691 * during replay we process one reference at a time, and we don't
692 * want to delete valid links to a file from the subvolume if that
693 * link is also in the log.
695 static noinline int backref_in_log(struct btrfs_root *log,
696 struct btrfs_key *key,
697 char *name, int namelen)
699 struct btrfs_path *path;
700 struct btrfs_inode_ref *ref;
702 unsigned long ptr_end;
703 unsigned long name_ptr;
709 path = btrfs_alloc_path();
710 ret = btrfs_search_slot(NULL, log, key, path, 0, 0);
714 item_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]);
715 ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
716 ptr_end = ptr + item_size;
717 while (ptr < ptr_end) {
718 ref = (struct btrfs_inode_ref *)ptr;
719 found_name_len = btrfs_inode_ref_name_len(path->nodes[0], ref);
720 if (found_name_len == namelen) {
721 name_ptr = (unsigned long)(ref + 1);
722 ret = memcmp_extent_buffer(path->nodes[0], name,
729 ptr = (unsigned long)(ref + 1) + found_name_len;
732 btrfs_free_path(path);
738 * replay one inode back reference item found in the log tree.
739 * eb, slot and key refer to the buffer and key found in the log tree.
740 * root is the destination we are replaying into, and path is for temp
741 * use by this function. (it should be released on return).
743 static noinline int add_inode_ref(struct btrfs_trans_handle *trans,
744 struct btrfs_root *root,
745 struct btrfs_root *log,
746 struct btrfs_path *path,
747 struct extent_buffer *eb, int slot,
748 struct btrfs_key *key)
752 struct btrfs_key location;
753 struct btrfs_inode_ref *ref;
754 struct btrfs_dir_item *di;
758 unsigned long ref_ptr;
759 unsigned long ref_end;
761 location.objectid = key->objectid;
762 location.type = BTRFS_INODE_ITEM_KEY;
766 * it is possible that we didn't log all the parent directories
767 * for a given inode. If we don't find the dir, just don't
768 * copy the back ref in. The link count fixup code will take
771 dir = read_one_inode(root, key->offset);
775 inode = read_one_inode(root, key->objectid);
778 ref_ptr = btrfs_item_ptr_offset(eb, slot);
779 ref_end = ref_ptr + btrfs_item_size_nr(eb, slot);
782 ref = (struct btrfs_inode_ref *)ref_ptr;
784 namelen = btrfs_inode_ref_name_len(eb, ref);
785 name = kmalloc(namelen, GFP_NOFS);
788 read_extent_buffer(eb, name, (unsigned long)(ref + 1), namelen);
790 /* if we already have a perfect match, we're done */
791 if (inode_in_dir(root, path, dir->i_ino, inode->i_ino,
792 btrfs_inode_ref_index(eb, ref),
798 * look for a conflicting back reference in the metadata.
799 * if we find one we have to unlink that name of the file
800 * before we add our new link. Later on, we overwrite any
801 * existing back reference, and we don't want to create
802 * dangling pointers in the directory.
805 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
809 struct btrfs_inode_ref *victim_ref;
811 unsigned long ptr_end;
812 struct extent_buffer *leaf = path->nodes[0];
814 /* are we trying to overwrite a back ref for the root directory
815 * if so, just jump out, we're done
817 if (key->objectid == key->offset)
820 /* check all the names in this back reference to see
821 * if they are in the log. if so, we allow them to stay
822 * otherwise they must be unlinked as a conflict
824 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
825 ptr_end = ptr + btrfs_item_size_nr(leaf, path->slots[0]);
826 while(ptr < ptr_end) {
827 victim_ref = (struct btrfs_inode_ref *)ptr;
828 victim_name_len = btrfs_inode_ref_name_len(leaf,
830 victim_name = kmalloc(victim_name_len, GFP_NOFS);
831 BUG_ON(!victim_name);
833 read_extent_buffer(leaf, victim_name,
834 (unsigned long)(victim_ref + 1),
837 if (!backref_in_log(log, key, victim_name,
839 btrfs_inc_nlink(inode);
840 btrfs_release_path(root, path);
841 ret = btrfs_unlink_inode(trans, root, dir,
845 btrfs_release_path(root, path);
849 ptr = (unsigned long)(victim_ref + 1) + victim_name_len;
853 btrfs_release_path(root, path);
855 /* look for a conflicting sequence number */
856 di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
857 btrfs_inode_ref_index(eb, ref),
859 if (di && !IS_ERR(di)) {
860 ret = drop_one_dir_item(trans, root, path, dir, di);
863 btrfs_release_path(root, path);
866 /* look for a conflicting name */
867 di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
869 if (di && !IS_ERR(di)) {
870 ret = drop_one_dir_item(trans, root, path, dir, di);
873 btrfs_release_path(root, path);
875 /* insert our name */
876 ret = btrfs_add_link(trans, dir, inode, name, namelen, 0,
877 btrfs_inode_ref_index(eb, ref));
880 btrfs_update_inode(trans, root, inode);
883 ref_ptr = (unsigned long)(ref + 1) + namelen;
885 if (ref_ptr < ref_end)
888 /* finally write the back reference in the inode */
889 ret = overwrite_item(trans, root, path, eb, slot, key);
893 btrfs_release_path(root, path);
900 * replay one csum item from the log tree into the subvolume 'root'
901 * eb, slot and key all refer to the log tree
902 * path is for temp use by this function and should be released on return
904 * This copies the checksums out of the log tree and inserts them into
905 * the subvolume. Any existing checksums for this range in the file
906 * are overwritten, and new items are added where required.
908 * We keep this simple by reusing the btrfs_ordered_sum code from
909 * the data=ordered mode. This basically means making a copy
910 * of all the checksums in ram, which we have to do anyway for kmap
913 * The copy is then sent down to btrfs_csum_file_blocks, which
914 * does all the hard work of finding existing items in the file
915 * or adding new ones.
917 static noinline int replay_one_csum(struct btrfs_trans_handle *trans,
918 struct btrfs_root *root,
919 struct btrfs_path *path,
920 struct extent_buffer *eb, int slot,
921 struct btrfs_key *key)
924 u32 item_size = btrfs_item_size_nr(eb, slot);
926 unsigned long file_bytes;
927 struct btrfs_ordered_sum *sums;
928 struct btrfs_sector_sum *sector_sum;
932 file_bytes = (item_size / BTRFS_CRC32_SIZE) * root->sectorsize;
933 inode = read_one_inode(root, key->objectid);
938 sums = kzalloc(btrfs_ordered_sum_size(root, file_bytes), GFP_NOFS);
944 INIT_LIST_HEAD(&sums->list);
945 sums->len = file_bytes;
946 sums->file_offset = key->offset;
949 * copy all the sums into the ordered sum struct
951 sector_sum = sums->sums;
952 cur_offset = key->offset;
953 ptr = btrfs_item_ptr_offset(eb, slot);
954 while(item_size > 0) {
955 sector_sum->offset = cur_offset;
956 read_extent_buffer(eb, §or_sum->sum, ptr, BTRFS_CRC32_SIZE);
958 item_size -= BTRFS_CRC32_SIZE;
959 ptr += BTRFS_CRC32_SIZE;
960 cur_offset += root->sectorsize;
963 /* let btrfs_csum_file_blocks add them into the file */
964 ret = btrfs_csum_file_blocks(trans, root, inode, sums);
972 * There are a few corners where the link count of the file can't
973 * be properly maintained during replay. So, instead of adding
974 * lots of complexity to the log code, we just scan the backrefs
975 * for any file that has been through replay.
977 * The scan will update the link count on the inode to reflect the
978 * number of back refs found. If it goes down to zero, the iput
979 * will free the inode.
981 static noinline int fixup_inode_link_count(struct btrfs_trans_handle *trans,
982 struct btrfs_root *root,
985 struct btrfs_path *path;
987 struct btrfs_key key;
990 unsigned long ptr_end;
993 key.objectid = inode->i_ino;
994 key.type = BTRFS_INODE_REF_KEY;
995 key.offset = (u64)-1;
997 path = btrfs_alloc_path();
1000 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1004 if (path->slots[0] == 0)
1008 btrfs_item_key_to_cpu(path->nodes[0], &key,
1010 if (key.objectid != inode->i_ino ||
1011 key.type != BTRFS_INODE_REF_KEY)
1013 ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
1014 ptr_end = ptr + btrfs_item_size_nr(path->nodes[0],
1016 while(ptr < ptr_end) {
1017 struct btrfs_inode_ref *ref;
1019 ref = (struct btrfs_inode_ref *)ptr;
1020 name_len = btrfs_inode_ref_name_len(path->nodes[0],
1022 ptr = (unsigned long)(ref + 1) + name_len;
1026 if (key.offset == 0)
1029 btrfs_release_path(root, path);
1031 btrfs_free_path(path);
1032 if (nlink != inode->i_nlink) {
1033 inode->i_nlink = nlink;
1034 btrfs_update_inode(trans, root, inode);
1036 BTRFS_I(inode)->index_cnt = (u64)-1;
1041 static noinline int fixup_inode_link_counts(struct btrfs_trans_handle *trans,
1042 struct btrfs_root *root,
1043 struct btrfs_path *path)
1046 struct btrfs_key key;
1047 struct inode *inode;
1049 key.objectid = BTRFS_TREE_LOG_FIXUP_OBJECTID;
1050 key.type = BTRFS_ORPHAN_ITEM_KEY;
1051 key.offset = (u64)-1;
1053 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1058 if (path->slots[0] == 0)
1063 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1064 if (key.objectid != BTRFS_TREE_LOG_FIXUP_OBJECTID ||
1065 key.type != BTRFS_ORPHAN_ITEM_KEY)
1068 ret = btrfs_del_item(trans, root, path);
1071 btrfs_release_path(root, path);
1072 inode = read_one_inode(root, key.offset);
1075 ret = fixup_inode_link_count(trans, root, inode);
1080 if (key.offset == 0)
1084 btrfs_release_path(root, path);
1090 * record a given inode in the fixup dir so we can check its link
1091 * count when replay is done. The link count is incremented here
1092 * so the inode won't go away until we check it
1094 static noinline int link_to_fixup_dir(struct btrfs_trans_handle *trans,
1095 struct btrfs_root *root,
1096 struct btrfs_path *path,
1099 struct btrfs_key key;
1101 struct inode *inode;
1103 inode = read_one_inode(root, objectid);
1106 key.objectid = BTRFS_TREE_LOG_FIXUP_OBJECTID;
1107 btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
1108 key.offset = objectid;
1110 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1112 btrfs_release_path(root, path);
1114 btrfs_inc_nlink(inode);
1115 btrfs_update_inode(trans, root, inode);
1116 } else if (ret == -EEXIST) {
1127 * when replaying the log for a directory, we only insert names
1128 * for inodes that actually exist. This means an fsync on a directory
1129 * does not implicitly fsync all the new files in it
1131 static noinline int insert_one_name(struct btrfs_trans_handle *trans,
1132 struct btrfs_root *root,
1133 struct btrfs_path *path,
1134 u64 dirid, u64 index,
1135 char *name, int name_len, u8 type,
1136 struct btrfs_key *location)
1138 struct inode *inode;
1142 inode = read_one_inode(root, location->objectid);
1146 dir = read_one_inode(root, dirid);
1151 ret = btrfs_add_link(trans, dir, inode, name, name_len, 1, index);
1153 /* FIXME, put inode into FIXUP list */
1161 * take a single entry in a log directory item and replay it into
1164 * if a conflicting item exists in the subdirectory already,
1165 * the inode it points to is unlinked and put into the link count
1168 * If a name from the log points to a file or directory that does
1169 * not exist in the FS, it is skipped. fsyncs on directories
1170 * do not force down inodes inside that directory, just changes to the
1171 * names or unlinks in a directory.
1173 static noinline int replay_one_name(struct btrfs_trans_handle *trans,
1174 struct btrfs_root *root,
1175 struct btrfs_path *path,
1176 struct extent_buffer *eb,
1177 struct btrfs_dir_item *di,
1178 struct btrfs_key *key)
1182 struct btrfs_dir_item *dst_di;
1183 struct btrfs_key found_key;
1184 struct btrfs_key log_key;
1190 dir = read_one_inode(root, key->objectid);
1193 name_len = btrfs_dir_name_len(eb, di);
1194 name = kmalloc(name_len, GFP_NOFS);
1195 log_type = btrfs_dir_type(eb, di);
1196 read_extent_buffer(eb, name, (unsigned long)(di + 1),
1199 btrfs_dir_item_key_to_cpu(eb, di, &log_key);
1200 exists = btrfs_lookup_inode(trans, root, path, &log_key, 0);
1205 btrfs_release_path(root, path);
1207 if (key->type == BTRFS_DIR_ITEM_KEY) {
1208 dst_di = btrfs_lookup_dir_item(trans, root, path, key->objectid,
1211 else if (key->type == BTRFS_DIR_INDEX_KEY) {
1212 dst_di = btrfs_lookup_dir_index_item(trans, root, path,
1219 if (!dst_di || IS_ERR(dst_di)) {
1220 /* we need a sequence number to insert, so we only
1221 * do inserts for the BTRFS_DIR_INDEX_KEY types
1223 if (key->type != BTRFS_DIR_INDEX_KEY)
1228 btrfs_dir_item_key_to_cpu(path->nodes[0], dst_di, &found_key);
1229 /* the existing item matches the logged item */
1230 if (found_key.objectid == log_key.objectid &&
1231 found_key.type == log_key.type &&
1232 found_key.offset == log_key.offset &&
1233 btrfs_dir_type(path->nodes[0], dst_di) == log_type) {
1238 * don't drop the conflicting directory entry if the inode
1239 * for the new entry doesn't exist
1244 ret = drop_one_dir_item(trans, root, path, dir, dst_di);
1247 if (key->type == BTRFS_DIR_INDEX_KEY)
1250 btrfs_release_path(root, path);
1256 btrfs_release_path(root, path);
1257 ret = insert_one_name(trans, root, path, key->objectid, key->offset,
1258 name, name_len, log_type, &log_key);
1260 if (ret && ret != -ENOENT)
1266 * find all the names in a directory item and reconcile them into
1267 * the subvolume. Only BTRFS_DIR_ITEM_KEY types will have more than
1268 * one name in a directory item, but the same code gets used for
1269 * both directory index types
1271 static noinline int replay_one_dir_item(struct btrfs_trans_handle *trans,
1272 struct btrfs_root *root,
1273 struct btrfs_path *path,
1274 struct extent_buffer *eb, int slot,
1275 struct btrfs_key *key)
1278 u32 item_size = btrfs_item_size_nr(eb, slot);
1279 struct btrfs_dir_item *di;
1282 unsigned long ptr_end;
1284 ptr = btrfs_item_ptr_offset(eb, slot);
1285 ptr_end = ptr + item_size;
1286 while(ptr < ptr_end) {
1287 di = (struct btrfs_dir_item *)ptr;
1288 name_len = btrfs_dir_name_len(eb, di);
1289 ret = replay_one_name(trans, root, path, eb, di, key);
1291 ptr = (unsigned long)(di + 1);
1298 * directory replay has two parts. There are the standard directory
1299 * items in the log copied from the subvolume, and range items
1300 * created in the log while the subvolume was logged.
1302 * The range items tell us which parts of the key space the log
1303 * is authoritative for. During replay, if a key in the subvolume
1304 * directory is in a logged range item, but not actually in the log
1305 * that means it was deleted from the directory before the fsync
1306 * and should be removed.
1308 static noinline int find_dir_range(struct btrfs_root *root,
1309 struct btrfs_path *path,
1310 u64 dirid, int key_type,
1311 u64 *start_ret, u64 *end_ret)
1313 struct btrfs_key key;
1315 struct btrfs_dir_log_item *item;
1319 if (*start_ret == (u64)-1)
1322 key.objectid = dirid;
1323 key.type = key_type;
1324 key.offset = *start_ret;
1326 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1330 if (path->slots[0] == 0)
1335 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1337 if (key.type != key_type || key.objectid != dirid) {
1341 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
1342 struct btrfs_dir_log_item);
1343 found_end = btrfs_dir_log_end(path->nodes[0], item);
1345 if (*start_ret >= key.offset && *start_ret <= found_end) {
1347 *start_ret = key.offset;
1348 *end_ret = found_end;
1353 /* check the next slot in the tree to see if it is a valid item */
1354 nritems = btrfs_header_nritems(path->nodes[0]);
1355 if (path->slots[0] >= nritems) {
1356 ret = btrfs_next_leaf(root, path);
1363 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1365 if (key.type != key_type || key.objectid != dirid) {
1369 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
1370 struct btrfs_dir_log_item);
1371 found_end = btrfs_dir_log_end(path->nodes[0], item);
1372 *start_ret = key.offset;
1373 *end_ret = found_end;
1376 btrfs_release_path(root, path);
1381 * this looks for a given directory item in the log. If the directory
1382 * item is not in the log, the item is removed and the inode it points
1385 static noinline int check_item_in_log(struct btrfs_trans_handle *trans,
1386 struct btrfs_root *root,
1387 struct btrfs_root *log,
1388 struct btrfs_path *path,
1389 struct btrfs_path *log_path,
1391 struct btrfs_key *dir_key)
1394 struct extent_buffer *eb;
1397 struct btrfs_dir_item *di;
1398 struct btrfs_dir_item *log_di;
1401 unsigned long ptr_end;
1403 struct inode *inode;
1404 struct btrfs_key location;
1407 eb = path->nodes[0];
1408 slot = path->slots[0];
1409 item_size = btrfs_item_size_nr(eb, slot);
1410 ptr = btrfs_item_ptr_offset(eb, slot);
1411 ptr_end = ptr + item_size;
1412 while(ptr < ptr_end) {
1413 di = (struct btrfs_dir_item *)ptr;
1414 name_len = btrfs_dir_name_len(eb, di);
1415 name = kmalloc(name_len, GFP_NOFS);
1420 read_extent_buffer(eb, name, (unsigned long)(di + 1),
1423 if (dir_key->type == BTRFS_DIR_ITEM_KEY) {
1424 log_di = btrfs_lookup_dir_item(trans, log, log_path,
1427 } else if (dir_key->type == BTRFS_DIR_INDEX_KEY) {
1428 log_di = btrfs_lookup_dir_index_item(trans, log,
1434 if (!log_di || IS_ERR(log_di)) {
1435 btrfs_dir_item_key_to_cpu(eb, di, &location);
1436 btrfs_release_path(root, path);
1437 btrfs_release_path(log, log_path);
1438 inode = read_one_inode(root, location.objectid);
1441 ret = link_to_fixup_dir(trans, root,
1442 path, location.objectid);
1444 btrfs_inc_nlink(inode);
1445 ret = btrfs_unlink_inode(trans, root, dir, inode,
1451 /* there might still be more names under this key
1452 * check and repeat if required
1454 ret = btrfs_search_slot(NULL, root, dir_key, path,
1461 btrfs_release_path(log, log_path);
1464 ptr = (unsigned long)(di + 1);
1469 btrfs_release_path(root, path);
1470 btrfs_release_path(log, log_path);
1475 * deletion replay happens before we copy any new directory items
1476 * out of the log or out of backreferences from inodes. It
1477 * scans the log to find ranges of keys that log is authoritative for,
1478 * and then scans the directory to find items in those ranges that are
1479 * not present in the log.
1481 * Anything we don't find in the log is unlinked and removed from the
1484 static noinline int replay_dir_deletes(struct btrfs_trans_handle *trans,
1485 struct btrfs_root *root,
1486 struct btrfs_root *log,
1487 struct btrfs_path *path,
1492 int key_type = BTRFS_DIR_LOG_ITEM_KEY;
1494 struct btrfs_key dir_key;
1495 struct btrfs_key found_key;
1496 struct btrfs_path *log_path;
1499 dir_key.objectid = dirid;
1500 dir_key.type = BTRFS_DIR_ITEM_KEY;
1501 log_path = btrfs_alloc_path();
1505 dir = read_one_inode(root, dirid);
1506 /* it isn't an error if the inode isn't there, that can happen
1507 * because we replay the deletes before we copy in the inode item
1511 btrfs_free_path(log_path);
1518 ret = find_dir_range(log, path, dirid, key_type,
1519 &range_start, &range_end);
1523 dir_key.offset = range_start;
1526 ret = btrfs_search_slot(NULL, root, &dir_key, path,
1531 nritems = btrfs_header_nritems(path->nodes[0]);
1532 if (path->slots[0] >= nritems) {
1533 ret = btrfs_next_leaf(root, path);
1537 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1539 if (found_key.objectid != dirid ||
1540 found_key.type != dir_key.type)
1543 if (found_key.offset > range_end)
1546 ret = check_item_in_log(trans, root, log, path,
1547 log_path, dir, &found_key);
1549 if (found_key.offset == (u64)-1)
1551 dir_key.offset = found_key.offset + 1;
1553 btrfs_release_path(root, path);
1554 if (range_end == (u64)-1)
1556 range_start = range_end + 1;
1561 if (key_type == BTRFS_DIR_LOG_ITEM_KEY) {
1562 key_type = BTRFS_DIR_LOG_INDEX_KEY;
1563 dir_key.type = BTRFS_DIR_INDEX_KEY;
1564 btrfs_release_path(root, path);
1568 btrfs_release_path(root, path);
1569 btrfs_free_path(log_path);
1575 * the process_func used to replay items from the log tree. This
1576 * gets called in two different stages. The first stage just looks
1577 * for inodes and makes sure they are all copied into the subvolume.
1579 * The second stage copies all the other item types from the log into
1580 * the subvolume. The two stage approach is slower, but gets rid of
1581 * lots of complexity around inodes referencing other inodes that exist
1582 * only in the log (references come from either directory items or inode
1585 static int replay_one_buffer(struct btrfs_root *log, struct extent_buffer *eb,
1586 struct walk_control *wc, u64 gen)
1589 struct btrfs_path *path;
1590 struct btrfs_root *root = wc->replay_dest;
1591 struct btrfs_key key;
1597 btrfs_read_buffer(eb, gen);
1599 level = btrfs_header_level(eb);
1604 path = btrfs_alloc_path();
1607 nritems = btrfs_header_nritems(eb);
1608 for (i = 0; i < nritems; i++) {
1609 btrfs_item_key_to_cpu(eb, &key, i);
1610 item_size = btrfs_item_size_nr(eb, i);
1612 /* inode keys are done during the first stage */
1613 if (key.type == BTRFS_INODE_ITEM_KEY &&
1614 wc->stage == LOG_WALK_REPLAY_INODES) {
1615 struct inode *inode;
1616 struct btrfs_inode_item *inode_item;
1619 inode_item = btrfs_item_ptr(eb, i,
1620 struct btrfs_inode_item);
1621 mode = btrfs_inode_mode(eb, inode_item);
1622 if (S_ISDIR(mode)) {
1623 ret = replay_dir_deletes(wc->trans,
1624 root, log, path, key.objectid);
1627 ret = overwrite_item(wc->trans, root, path,
1631 /* for regular files, truncate away
1632 * extents past the new EOF
1634 if (S_ISREG(mode)) {
1635 inode = read_one_inode(root,
1639 ret = btrfs_truncate_inode_items(wc->trans,
1640 root, inode, inode->i_size,
1641 BTRFS_EXTENT_DATA_KEY);
1645 ret = link_to_fixup_dir(wc->trans, root,
1646 path, key.objectid);
1649 if (wc->stage < LOG_WALK_REPLAY_ALL)
1652 /* these keys are simply copied */
1653 if (key.type == BTRFS_XATTR_ITEM_KEY) {
1654 ret = overwrite_item(wc->trans, root, path,
1657 } else if (key.type == BTRFS_INODE_REF_KEY) {
1658 ret = add_inode_ref(wc->trans, root, log, path,
1660 BUG_ON(ret && ret != -ENOENT);
1661 } else if (key.type == BTRFS_EXTENT_DATA_KEY) {
1662 ret = replay_one_extent(wc->trans, root, path,
1665 } else if (key.type == BTRFS_CSUM_ITEM_KEY) {
1666 ret = replay_one_csum(wc->trans, root, path,
1669 } else if (key.type == BTRFS_DIR_ITEM_KEY ||
1670 key.type == BTRFS_DIR_INDEX_KEY) {
1671 ret = replay_one_dir_item(wc->trans, root, path,
1676 btrfs_free_path(path);
1680 static int noinline walk_down_log_tree(struct btrfs_trans_handle *trans,
1681 struct btrfs_root *root,
1682 struct btrfs_path *path, int *level,
1683 struct walk_control *wc)
1689 struct extent_buffer *next;
1690 struct extent_buffer *cur;
1691 struct extent_buffer *parent;
1695 WARN_ON(*level < 0);
1696 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1699 WARN_ON(*level < 0);
1700 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1701 cur = path->nodes[*level];
1703 if (btrfs_header_level(cur) != *level)
1706 if (path->slots[*level] >=
1707 btrfs_header_nritems(cur))
1710 bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
1711 ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
1712 blocksize = btrfs_level_size(root, *level - 1);
1714 parent = path->nodes[*level];
1715 root_owner = btrfs_header_owner(parent);
1716 root_gen = btrfs_header_generation(parent);
1718 next = btrfs_find_create_tree_block(root, bytenr, blocksize);
1720 wc->process_func(root, next, wc, ptr_gen);
1723 path->slots[*level]++;
1725 btrfs_read_buffer(next, ptr_gen);
1727 btrfs_tree_lock(next);
1728 clean_tree_block(trans, root, next);
1729 btrfs_wait_tree_block_writeback(next);
1730 btrfs_tree_unlock(next);
1732 ret = btrfs_drop_leaf_ref(trans, root, next);
1735 WARN_ON(root_owner !=
1736 BTRFS_TREE_LOG_OBJECTID);
1737 ret = btrfs_free_reserved_extent(root,
1741 free_extent_buffer(next);
1744 btrfs_read_buffer(next, ptr_gen);
1746 WARN_ON(*level <= 0);
1747 if (path->nodes[*level-1])
1748 free_extent_buffer(path->nodes[*level-1]);
1749 path->nodes[*level-1] = next;
1750 *level = btrfs_header_level(next);
1751 path->slots[*level] = 0;
1754 WARN_ON(*level < 0);
1755 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1757 if (path->nodes[*level] == root->node) {
1758 parent = path->nodes[*level];
1760 parent = path->nodes[*level + 1];
1762 bytenr = path->nodes[*level]->start;
1764 blocksize = btrfs_level_size(root, *level);
1765 root_owner = btrfs_header_owner(parent);
1766 root_gen = btrfs_header_generation(parent);
1768 wc->process_func(root, path->nodes[*level], wc,
1769 btrfs_header_generation(path->nodes[*level]));
1772 next = path->nodes[*level];
1773 btrfs_tree_lock(next);
1774 clean_tree_block(trans, root, next);
1775 btrfs_wait_tree_block_writeback(next);
1776 btrfs_tree_unlock(next);
1779 ret = btrfs_drop_leaf_ref(trans, root, next);
1782 WARN_ON(root_owner != BTRFS_TREE_LOG_OBJECTID);
1783 ret = btrfs_free_reserved_extent(root, bytenr, blocksize);
1786 free_extent_buffer(path->nodes[*level]);
1787 path->nodes[*level] = NULL;
1794 static int noinline walk_up_log_tree(struct btrfs_trans_handle *trans,
1795 struct btrfs_root *root,
1796 struct btrfs_path *path, int *level,
1797 struct walk_control *wc)
1805 for(i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
1806 slot = path->slots[i];
1807 if (slot < btrfs_header_nritems(path->nodes[i]) - 1) {
1808 struct extent_buffer *node;
1809 node = path->nodes[i];
1812 WARN_ON(*level == 0);
1815 struct extent_buffer *parent;
1816 if (path->nodes[*level] == root->node)
1817 parent = path->nodes[*level];
1819 parent = path->nodes[*level + 1];
1821 root_owner = btrfs_header_owner(parent);
1822 root_gen = btrfs_header_generation(parent);
1823 wc->process_func(root, path->nodes[*level], wc,
1824 btrfs_header_generation(path->nodes[*level]));
1826 struct extent_buffer *next;
1828 next = path->nodes[*level];
1830 btrfs_tree_lock(next);
1831 clean_tree_block(trans, root, next);
1832 btrfs_wait_tree_block_writeback(next);
1833 btrfs_tree_unlock(next);
1836 ret = btrfs_drop_leaf_ref(trans, root,
1841 WARN_ON(root_owner != BTRFS_TREE_LOG_OBJECTID);
1842 ret = btrfs_free_reserved_extent(root,
1843 path->nodes[*level]->start,
1844 path->nodes[*level]->len);
1847 free_extent_buffer(path->nodes[*level]);
1848 path->nodes[*level] = NULL;
1856 * drop the reference count on the tree rooted at 'snap'. This traverses
1857 * the tree freeing any blocks that have a ref count of zero after being
1860 static int walk_log_tree(struct btrfs_trans_handle *trans,
1861 struct btrfs_root *log, struct walk_control *wc)
1866 struct btrfs_path *path;
1870 path = btrfs_alloc_path();
1873 level = btrfs_header_level(log->node);
1875 path->nodes[level] = log->node;
1876 extent_buffer_get(log->node);
1877 path->slots[level] = 0;
1880 wret = walk_down_log_tree(trans, log, path, &level, wc);
1886 wret = walk_up_log_tree(trans, log, path, &level, wc);
1893 /* was the root node processed? if not, catch it here */
1894 if (path->nodes[orig_level]) {
1895 wc->process_func(log, path->nodes[orig_level], wc,
1896 btrfs_header_generation(path->nodes[orig_level]));
1898 struct extent_buffer *next;
1900 next = path->nodes[orig_level];
1902 btrfs_tree_lock(next);
1903 clean_tree_block(trans, log, next);
1904 btrfs_wait_tree_block_writeback(next);
1905 btrfs_tree_unlock(next);
1907 if (orig_level == 0) {
1908 ret = btrfs_drop_leaf_ref(trans, log,
1912 WARN_ON(log->root_key.objectid !=
1913 BTRFS_TREE_LOG_OBJECTID);
1914 ret = btrfs_free_reserved_extent(log, next->start,
1920 for (i = 0; i <= orig_level; i++) {
1921 if (path->nodes[i]) {
1922 free_extent_buffer(path->nodes[i]);
1923 path->nodes[i] = NULL;
1926 btrfs_free_path(path);
1928 free_extent_buffer(log->node);
1932 int wait_log_commit(struct btrfs_root *log)
1935 u64 transid = log->fs_info->tree_log_transid;
1938 prepare_to_wait(&log->fs_info->tree_log_wait, &wait,
1939 TASK_UNINTERRUPTIBLE);
1940 mutex_unlock(&log->fs_info->tree_log_mutex);
1941 if (atomic_read(&log->fs_info->tree_log_commit))
1943 finish_wait(&log->fs_info->tree_log_wait, &wait);
1944 mutex_lock(&log->fs_info->tree_log_mutex);
1945 } while(transid == log->fs_info->tree_log_transid &&
1946 atomic_read(&log->fs_info->tree_log_commit));
1951 * btrfs_sync_log does sends a given tree log down to the disk and
1952 * updates the super blocks to record it. When this call is done,
1953 * you know that any inodes previously logged are safely on disk
1955 int btrfs_sync_log(struct btrfs_trans_handle *trans,
1956 struct btrfs_root *root)
1959 unsigned long batch;
1960 struct btrfs_root *log = root->log_root;
1962 mutex_lock(&log->fs_info->tree_log_mutex);
1963 if (atomic_read(&log->fs_info->tree_log_commit)) {
1964 wait_log_commit(log);
1967 atomic_set(&log->fs_info->tree_log_commit, 1);
1970 batch = log->fs_info->tree_log_batch;
1971 mutex_unlock(&log->fs_info->tree_log_mutex);
1972 schedule_timeout_uninterruptible(1);
1973 mutex_lock(&log->fs_info->tree_log_mutex);
1975 while(atomic_read(&log->fs_info->tree_log_writers)) {
1977 prepare_to_wait(&log->fs_info->tree_log_wait, &wait,
1978 TASK_UNINTERRUPTIBLE);
1979 mutex_unlock(&log->fs_info->tree_log_mutex);
1980 if (atomic_read(&log->fs_info->tree_log_writers))
1982 mutex_lock(&log->fs_info->tree_log_mutex);
1983 finish_wait(&log->fs_info->tree_log_wait, &wait);
1985 if (batch == log->fs_info->tree_log_batch)
1989 ret = btrfs_write_and_wait_marked_extents(log, &log->dirty_log_pages);
1991 ret = btrfs_write_and_wait_marked_extents(root->fs_info->log_root_tree,
1992 &root->fs_info->log_root_tree->dirty_log_pages);
1995 btrfs_set_super_log_root(&root->fs_info->super_for_commit,
1996 log->fs_info->log_root_tree->node->start);
1997 btrfs_set_super_log_root_level(&root->fs_info->super_for_commit,
1998 btrfs_header_level(log->fs_info->log_root_tree->node));
2000 write_ctree_super(trans, log->fs_info->tree_root);
2001 log->fs_info->tree_log_transid++;
2002 log->fs_info->tree_log_batch = 0;
2003 atomic_set(&log->fs_info->tree_log_commit, 0);
2005 if (waitqueue_active(&log->fs_info->tree_log_wait))
2006 wake_up(&log->fs_info->tree_log_wait);
2008 mutex_unlock(&log->fs_info->tree_log_mutex);
2013 /* * free all the extents used by the tree log. This should be called
2014 * at commit time of the full transaction
2016 int btrfs_free_log(struct btrfs_trans_handle *trans, struct btrfs_root *root)
2019 struct btrfs_root *log;
2023 struct walk_control wc = {
2025 .process_func = process_one_buffer
2028 if (!root->log_root)
2031 log = root->log_root;
2032 ret = walk_log_tree(trans, log, &wc);
2036 ret = find_first_extent_bit(&log->dirty_log_pages,
2037 0, &start, &end, EXTENT_DIRTY);
2041 clear_extent_dirty(&log->dirty_log_pages,
2042 start, end, GFP_NOFS);
2045 log = root->log_root;
2046 ret = btrfs_del_root(trans, root->fs_info->log_root_tree,
2049 root->log_root = NULL;
2050 kfree(root->log_root);
2055 * helper function to update the item for a given subvolumes log root
2056 * in the tree of log roots
2058 static int update_log_root(struct btrfs_trans_handle *trans,
2059 struct btrfs_root *log)
2061 u64 bytenr = btrfs_root_bytenr(&log->root_item);
2064 if (log->node->start == bytenr)
2067 btrfs_set_root_bytenr(&log->root_item, log->node->start);
2068 btrfs_set_root_level(&log->root_item, btrfs_header_level(log->node));
2069 ret = btrfs_update_root(trans, log->fs_info->log_root_tree,
2070 &log->root_key, &log->root_item);
2076 * If both a file and directory are logged, and unlinks or renames are
2077 * mixed in, we have a few interesting corners:
2079 * create file X in dir Y
2080 * link file X to X.link in dir Y
2082 * unlink file X but leave X.link
2085 * After a crash we would expect only X.link to exist. But file X
2086 * didn't get fsync'd again so the log has back refs for X and X.link.
2088 * We solve this by removing directory entries and inode backrefs from the
2089 * log when a file that was logged in the current transaction is
2090 * unlinked. Any later fsync will include the updated log entries, and
2091 * we'll be able to reconstruct the proper directory items from backrefs.
2093 * This optimizations allows us to avoid relogging the entire inode
2094 * or the entire directory.
2096 int btrfs_del_dir_entries_in_log(struct btrfs_trans_handle *trans,
2097 struct btrfs_root *root,
2098 const char *name, int name_len,
2099 struct inode *dir, u64 index)
2101 struct btrfs_root *log;
2102 struct btrfs_dir_item *di;
2103 struct btrfs_path *path;
2107 if (BTRFS_I(dir)->logged_trans < trans->transid)
2110 ret = join_running_log_trans(root);
2114 mutex_lock(&BTRFS_I(dir)->log_mutex);
2116 log = root->log_root;
2117 path = btrfs_alloc_path();
2118 di = btrfs_lookup_dir_item(trans, log, path, dir->i_ino,
2119 name, name_len, -1);
2120 if (di && !IS_ERR(di)) {
2121 ret = btrfs_delete_one_dir_name(trans, log, path, di);
2122 bytes_del += name_len;
2125 btrfs_release_path(log, path);
2126 di = btrfs_lookup_dir_index_item(trans, log, path, dir->i_ino,
2127 index, name, name_len, -1);
2128 if (di && !IS_ERR(di)) {
2129 ret = btrfs_delete_one_dir_name(trans, log, path, di);
2130 bytes_del += name_len;
2134 /* update the directory size in the log to reflect the names
2138 struct btrfs_key key;
2140 key.objectid = dir->i_ino;
2142 key.type = BTRFS_INODE_ITEM_KEY;
2143 btrfs_release_path(log, path);
2145 ret = btrfs_search_slot(trans, log, &key, path, 0, 1);
2147 struct btrfs_inode_item *item;
2150 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2151 struct btrfs_inode_item);
2152 i_size = btrfs_inode_size(path->nodes[0], item);
2153 if (i_size > bytes_del)
2154 i_size -= bytes_del;
2157 btrfs_set_inode_size(path->nodes[0], item, i_size);
2158 btrfs_mark_buffer_dirty(path->nodes[0]);
2161 btrfs_release_path(log, path);
2164 btrfs_free_path(path);
2165 mutex_unlock(&BTRFS_I(dir)->log_mutex);
2166 end_log_trans(root);
2171 /* see comments for btrfs_del_dir_entries_in_log */
2172 int btrfs_del_inode_ref_in_log(struct btrfs_trans_handle *trans,
2173 struct btrfs_root *root,
2174 const char *name, int name_len,
2175 struct inode *inode, u64 dirid)
2177 struct btrfs_root *log;
2181 if (BTRFS_I(inode)->logged_trans < trans->transid)
2184 ret = join_running_log_trans(root);
2187 log = root->log_root;
2188 mutex_lock(&BTRFS_I(inode)->log_mutex);
2190 ret = btrfs_del_inode_ref(trans, log, name, name_len, inode->i_ino,
2192 mutex_unlock(&BTRFS_I(inode)->log_mutex);
2193 end_log_trans(root);
2199 * creates a range item in the log for 'dirid'. first_offset and
2200 * last_offset tell us which parts of the key space the log should
2201 * be considered authoritative for.
2203 static noinline int insert_dir_log_key(struct btrfs_trans_handle *trans,
2204 struct btrfs_root *log,
2205 struct btrfs_path *path,
2206 int key_type, u64 dirid,
2207 u64 first_offset, u64 last_offset)
2210 struct btrfs_key key;
2211 struct btrfs_dir_log_item *item;
2213 key.objectid = dirid;
2214 key.offset = first_offset;
2215 if (key_type == BTRFS_DIR_ITEM_KEY)
2216 key.type = BTRFS_DIR_LOG_ITEM_KEY;
2218 key.type = BTRFS_DIR_LOG_INDEX_KEY;
2219 ret = btrfs_insert_empty_item(trans, log, path, &key, sizeof(*item));
2222 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2223 struct btrfs_dir_log_item);
2224 btrfs_set_dir_log_end(path->nodes[0], item, last_offset);
2225 btrfs_mark_buffer_dirty(path->nodes[0]);
2226 btrfs_release_path(log, path);
2231 * log all the items included in the current transaction for a given
2232 * directory. This also creates the range items in the log tree required
2233 * to replay anything deleted before the fsync
2235 static noinline int log_dir_items(struct btrfs_trans_handle *trans,
2236 struct btrfs_root *root, struct inode *inode,
2237 struct btrfs_path *path,
2238 struct btrfs_path *dst_path, int key_type,
2239 u64 min_offset, u64 *last_offset_ret)
2241 struct btrfs_key min_key;
2242 struct btrfs_key max_key;
2243 struct btrfs_root *log = root->log_root;
2244 struct extent_buffer *src;
2248 u64 first_offset = min_offset;
2249 u64 last_offset = (u64)-1;
2251 log = root->log_root;
2252 max_key.objectid = inode->i_ino;
2253 max_key.offset = (u64)-1;
2254 max_key.type = key_type;
2256 min_key.objectid = inode->i_ino;
2257 min_key.type = key_type;
2258 min_key.offset = min_offset;
2260 path->keep_locks = 1;
2262 ret = btrfs_search_forward(root, &min_key, &max_key,
2263 path, 0, trans->transid);
2266 * we didn't find anything from this transaction, see if there
2267 * is anything at all
2269 if (ret != 0 || min_key.objectid != inode->i_ino ||
2270 min_key.type != key_type) {
2271 min_key.objectid = inode->i_ino;
2272 min_key.type = key_type;
2273 min_key.offset = (u64)-1;
2274 btrfs_release_path(root, path);
2275 ret = btrfs_search_slot(NULL, root, &min_key, path, 0, 0);
2277 btrfs_release_path(root, path);
2280 ret = btrfs_previous_item(root, path, inode->i_ino, key_type);
2282 /* if ret == 0 there are items for this type,
2283 * create a range to tell us the last key of this type.
2284 * otherwise, there are no items in this directory after
2285 * *min_offset, and we create a range to indicate that.
2288 struct btrfs_key tmp;
2289 btrfs_item_key_to_cpu(path->nodes[0], &tmp,
2291 if (key_type == tmp.type) {
2292 first_offset = max(min_offset, tmp.offset) + 1;
2298 /* go backward to find any previous key */
2299 ret = btrfs_previous_item(root, path, inode->i_ino, key_type);
2301 struct btrfs_key tmp;
2302 btrfs_item_key_to_cpu(path->nodes[0], &tmp, path->slots[0]);
2303 if (key_type == tmp.type) {
2304 first_offset = tmp.offset;
2305 ret = overwrite_item(trans, log, dst_path,
2306 path->nodes[0], path->slots[0],
2310 btrfs_release_path(root, path);
2312 /* find the first key from this transaction again */
2313 ret = btrfs_search_slot(NULL, root, &min_key, path, 0, 0);
2320 * we have a block from this transaction, log every item in it
2321 * from our directory
2324 struct btrfs_key tmp;
2325 src = path->nodes[0];
2326 nritems = btrfs_header_nritems(src);
2327 for (i = path->slots[0]; i < nritems; i++) {
2328 btrfs_item_key_to_cpu(src, &min_key, i);
2330 if (min_key.objectid != inode->i_ino ||
2331 min_key.type != key_type)
2333 ret = overwrite_item(trans, log, dst_path, src, i,
2337 path->slots[0] = nritems;
2340 * look ahead to the next item and see if it is also
2341 * from this directory and from this transaction
2343 ret = btrfs_next_leaf(root, path);
2345 last_offset = (u64)-1;
2348 btrfs_item_key_to_cpu(path->nodes[0], &tmp, path->slots[0]);
2349 if (tmp.objectid != inode->i_ino || tmp.type != key_type) {
2350 last_offset = (u64)-1;
2353 if (btrfs_header_generation(path->nodes[0]) != trans->transid) {
2354 ret = overwrite_item(trans, log, dst_path,
2355 path->nodes[0], path->slots[0],
2359 last_offset = tmp.offset;
2364 *last_offset_ret = last_offset;
2365 btrfs_release_path(root, path);
2366 btrfs_release_path(log, dst_path);
2368 /* insert the log range keys to indicate where the log is valid */
2369 ret = insert_dir_log_key(trans, log, path, key_type, inode->i_ino,
2370 first_offset, last_offset);
2376 * logging directories is very similar to logging inodes, We find all the items
2377 * from the current transaction and write them to the log.
2379 * The recovery code scans the directory in the subvolume, and if it finds a
2380 * key in the range logged that is not present in the log tree, then it means
2381 * that dir entry was unlinked during the transaction.
2383 * In order for that scan to work, we must include one key smaller than
2384 * the smallest logged by this transaction and one key larger than the largest
2385 * key logged by this transaction.
2387 static noinline int log_directory_changes(struct btrfs_trans_handle *trans,
2388 struct btrfs_root *root, struct inode *inode,
2389 struct btrfs_path *path,
2390 struct btrfs_path *dst_path)
2395 int key_type = BTRFS_DIR_ITEM_KEY;
2401 ret = log_dir_items(trans, root, inode, path,
2402 dst_path, key_type, min_key,
2405 if (max_key == (u64)-1)
2407 min_key = max_key + 1;
2410 if (key_type == BTRFS_DIR_ITEM_KEY) {
2411 key_type = BTRFS_DIR_INDEX_KEY;
2418 * a helper function to drop items from the log before we relog an
2419 * inode. max_key_type indicates the highest item type to remove.
2420 * This cannot be run for file data extents because it does not
2421 * free the extents they point to.
2423 static int drop_objectid_items(struct btrfs_trans_handle *trans,
2424 struct btrfs_root *log,
2425 struct btrfs_path *path,
2426 u64 objectid, int max_key_type)
2429 struct btrfs_key key;
2430 struct btrfs_key found_key;
2432 key.objectid = objectid;
2433 key.type = max_key_type;
2434 key.offset = (u64)-1;
2437 ret = btrfs_search_slot(trans, log, &key, path, -1, 1);
2442 if (path->slots[0] == 0)
2446 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
2449 if (found_key.objectid != objectid)
2452 ret = btrfs_del_item(trans, log, path);
2454 btrfs_release_path(log, path);
2456 btrfs_release_path(log, path);
2460 static noinline int copy_items(struct btrfs_trans_handle *trans,
2461 struct btrfs_root *log,
2462 struct btrfs_path *dst_path,
2463 struct extent_buffer *src,
2464 int start_slot, int nr, int inode_only)
2466 unsigned long src_offset;
2467 unsigned long dst_offset;
2468 struct btrfs_file_extent_item *extent;
2469 struct btrfs_inode_item *inode_item;
2471 struct btrfs_key *ins_keys;
2476 ins_data = kmalloc(nr * sizeof(struct btrfs_key) +
2477 nr * sizeof(u32), GFP_NOFS);
2478 ins_sizes = (u32 *)ins_data;
2479 ins_keys = (struct btrfs_key *)(ins_data + nr * sizeof(u32));
2481 for (i = 0; i < nr; i++) {
2482 ins_sizes[i] = btrfs_item_size_nr(src, i + start_slot);
2483 btrfs_item_key_to_cpu(src, ins_keys + i, i + start_slot);
2485 ret = btrfs_insert_empty_items(trans, log, dst_path,
2486 ins_keys, ins_sizes, nr);
2489 for (i = 0; i < nr; i++) {
2490 dst_offset = btrfs_item_ptr_offset(dst_path->nodes[0],
2491 dst_path->slots[0]);
2493 src_offset = btrfs_item_ptr_offset(src, start_slot + i);
2495 copy_extent_buffer(dst_path->nodes[0], src, dst_offset,
2496 src_offset, ins_sizes[i]);
2498 if (inode_only == LOG_INODE_EXISTS &&
2499 ins_keys[i].type == BTRFS_INODE_ITEM_KEY) {
2500 inode_item = btrfs_item_ptr(dst_path->nodes[0],
2502 struct btrfs_inode_item);
2503 btrfs_set_inode_size(dst_path->nodes[0], inode_item, 0);
2505 /* set the generation to zero so the recover code
2506 * can tell the difference between an logging
2507 * just to say 'this inode exists' and a logging
2508 * to say 'update this inode with these values'
2510 btrfs_set_inode_generation(dst_path->nodes[0],
2513 /* take a reference on file data extents so that truncates
2514 * or deletes of this inode don't have to relog the inode
2517 if (btrfs_key_type(ins_keys + i) == BTRFS_EXTENT_DATA_KEY) {
2519 extent = btrfs_item_ptr(src, start_slot + i,
2520 struct btrfs_file_extent_item);
2522 found_type = btrfs_file_extent_type(src, extent);
2523 if (found_type == BTRFS_FILE_EXTENT_REG) {
2524 u64 ds = btrfs_file_extent_disk_bytenr(src,
2526 u64 dl = btrfs_file_extent_disk_num_bytes(src,
2528 /* ds == 0 is a hole */
2530 ret = btrfs_inc_extent_ref(trans, log,
2532 dst_path->nodes[0]->start,
2533 BTRFS_TREE_LOG_OBJECTID,
2535 ins_keys[i].objectid);
2540 dst_path->slots[0]++;
2543 btrfs_mark_buffer_dirty(dst_path->nodes[0]);
2544 btrfs_release_path(log, dst_path);
2549 /* log a single inode in the tree log.
2550 * At least one parent directory for this inode must exist in the tree
2551 * or be logged already.
2553 * Any items from this inode changed by the current transaction are copied
2554 * to the log tree. An extra reference is taken on any extents in this
2555 * file, allowing us to avoid a whole pile of corner cases around logging
2556 * blocks that have been removed from the tree.
2558 * See LOG_INODE_ALL and related defines for a description of what inode_only
2561 * This handles both files and directories.
2563 static int __btrfs_log_inode(struct btrfs_trans_handle *trans,
2564 struct btrfs_root *root, struct inode *inode,
2567 struct btrfs_path *path;
2568 struct btrfs_path *dst_path;
2569 struct btrfs_key min_key;
2570 struct btrfs_key max_key;
2571 struct btrfs_root *log = root->log_root;
2572 struct extent_buffer *src = NULL;
2576 int ins_start_slot = 0;
2579 log = root->log_root;
2581 path = btrfs_alloc_path();
2582 dst_path = btrfs_alloc_path();
2584 min_key.objectid = inode->i_ino;
2585 min_key.type = BTRFS_INODE_ITEM_KEY;
2588 max_key.objectid = inode->i_ino;
2589 if (inode_only == LOG_INODE_EXISTS || S_ISDIR(inode->i_mode))
2590 max_key.type = BTRFS_XATTR_ITEM_KEY;
2592 max_key.type = (u8)-1;
2593 max_key.offset = (u64)-1;
2596 * if this inode has already been logged and we're in inode_only
2597 * mode, we don't want to delete the things that have already
2598 * been written to the log.
2600 * But, if the inode has been through an inode_only log,
2601 * the logged_trans field is not set. This allows us to catch
2602 * any new names for this inode in the backrefs by logging it
2605 if (inode_only == LOG_INODE_EXISTS &&
2606 BTRFS_I(inode)->logged_trans == trans->transid) {
2607 btrfs_free_path(path);
2608 btrfs_free_path(dst_path);
2611 mutex_lock(&BTRFS_I(inode)->log_mutex);
2614 * a brute force approach to making sure we get the most uptodate
2615 * copies of everything.
2617 if (S_ISDIR(inode->i_mode)) {
2618 int max_key_type = BTRFS_DIR_LOG_INDEX_KEY;
2620 if (inode_only == LOG_INODE_EXISTS)
2621 max_key_type = BTRFS_XATTR_ITEM_KEY;
2622 ret = drop_objectid_items(trans, log, path,
2623 inode->i_ino, max_key_type);
2625 ret = btrfs_truncate_inode_items(trans, log, inode, 0, 0);
2628 path->keep_locks = 1;
2632 ret = btrfs_search_forward(root, &min_key, &max_key,
2633 path, 0, trans->transid);
2637 /* note, ins_nr might be > 0 here, cleanup outside the loop */
2638 if (min_key.objectid != inode->i_ino)
2640 if (min_key.type > max_key.type)
2643 src = path->nodes[0];
2644 size = btrfs_item_size_nr(src, path->slots[0]);
2645 if (ins_nr && ins_start_slot + ins_nr == path->slots[0]) {
2648 } else if (!ins_nr) {
2649 ins_start_slot = path->slots[0];
2654 ret = copy_items(trans, log, dst_path, src, ins_start_slot,
2655 ins_nr, inode_only);
2658 ins_start_slot = path->slots[0];
2661 nritems = btrfs_header_nritems(path->nodes[0]);
2663 if (path->slots[0] < nritems) {
2664 btrfs_item_key_to_cpu(path->nodes[0], &min_key,
2669 ret = copy_items(trans, log, dst_path, src,
2671 ins_nr, inode_only);
2675 btrfs_release_path(root, path);
2677 if (min_key.offset < (u64)-1)
2679 else if (min_key.type < (u8)-1)
2681 else if (min_key.objectid < (u64)-1)
2687 ret = copy_items(trans, log, dst_path, src,
2689 ins_nr, inode_only);
2694 if (inode_only == LOG_INODE_ALL && S_ISDIR(inode->i_mode)) {
2695 btrfs_release_path(root, path);
2696 btrfs_release_path(log, dst_path);
2697 BTRFS_I(inode)->log_dirty_trans = 0;
2698 ret = log_directory_changes(trans, root, inode, path, dst_path);
2701 BTRFS_I(inode)->logged_trans = trans->transid;
2702 mutex_unlock(&BTRFS_I(inode)->log_mutex);
2704 btrfs_free_path(path);
2705 btrfs_free_path(dst_path);
2707 mutex_lock(&root->fs_info->tree_log_mutex);
2708 ret = update_log_root(trans, log);
2710 mutex_unlock(&root->fs_info->tree_log_mutex);
2715 int btrfs_log_inode(struct btrfs_trans_handle *trans,
2716 struct btrfs_root *root, struct inode *inode,
2721 start_log_trans(trans, root);
2722 ret = __btrfs_log_inode(trans, root, inode, inode_only);
2723 end_log_trans(root);
2728 * helper function around btrfs_log_inode to make sure newly created
2729 * parent directories also end up in the log. A minimal inode and backref
2730 * only logging is done of any parent directories that are older than
2731 * the last committed transaction
2733 int btrfs_log_dentry(struct btrfs_trans_handle *trans,
2734 struct btrfs_root *root, struct dentry *dentry)
2736 int inode_only = LOG_INODE_ALL;
2737 struct super_block *sb;
2740 start_log_trans(trans, root);
2741 sb = dentry->d_inode->i_sb;
2743 ret = __btrfs_log_inode(trans, root, dentry->d_inode,
2746 inode_only = LOG_INODE_EXISTS;
2748 dentry = dentry->d_parent;
2749 if (!dentry || !dentry->d_inode || sb != dentry->d_inode->i_sb)
2752 if (BTRFS_I(dentry->d_inode)->generation <=
2753 root->fs_info->last_trans_committed)
2756 end_log_trans(root);
2761 * it is not safe to log dentry if the chunk root has added new
2762 * chunks. This returns 0 if the dentry was logged, and 1 otherwise.
2763 * If this returns 1, you must commit the transaction to safely get your
2766 int btrfs_log_dentry_safe(struct btrfs_trans_handle *trans,
2767 struct btrfs_root *root, struct dentry *dentry)
2770 gen = root->fs_info->last_trans_new_blockgroup;
2771 if (gen > root->fs_info->last_trans_committed)
2774 return btrfs_log_dentry(trans, root, dentry);
2778 * should be called during mount to recover any replay any log trees
2781 int btrfs_recover_log_trees(struct btrfs_root *log_root_tree)
2784 struct btrfs_path *path;
2785 struct btrfs_trans_handle *trans;
2786 struct btrfs_key key;
2787 struct btrfs_key found_key;
2788 struct btrfs_key tmp_key;
2789 struct btrfs_root *log;
2790 struct btrfs_fs_info *fs_info = log_root_tree->fs_info;
2792 struct walk_control wc = {
2793 .process_func = process_one_buffer,
2797 fs_info->log_root_recovering = 1;
2798 path = btrfs_alloc_path();
2801 trans = btrfs_start_transaction(fs_info->tree_root, 1);
2806 walk_log_tree(trans, log_root_tree, &wc);
2809 key.objectid = BTRFS_TREE_LOG_OBJECTID;
2810 key.offset = (u64)-1;
2811 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
2814 ret = btrfs_search_slot(NULL, log_root_tree, &key, path, 0, 0);
2818 if (path->slots[0] == 0)
2822 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
2824 btrfs_release_path(log_root_tree, path);
2825 if (found_key.objectid != BTRFS_TREE_LOG_OBJECTID)
2828 log = btrfs_read_fs_root_no_radix(log_root_tree,
2833 tmp_key.objectid = found_key.offset;
2834 tmp_key.type = BTRFS_ROOT_ITEM_KEY;
2835 tmp_key.offset = (u64)-1;
2837 wc.replay_dest = btrfs_read_fs_root_no_name(fs_info, &tmp_key);
2839 BUG_ON(!wc.replay_dest);
2841 btrfs_record_root_in_trans(wc.replay_dest);
2842 ret = walk_log_tree(trans, log, &wc);
2845 if (wc.stage == LOG_WALK_REPLAY_ALL) {
2846 ret = fixup_inode_link_counts(trans, wc.replay_dest,
2850 ret = btrfs_find_highest_inode(wc.replay_dest, &highest_inode);
2852 wc.replay_dest->highest_inode = highest_inode;
2853 wc.replay_dest->last_inode_alloc = highest_inode;
2856 key.offset = found_key.offset - 1;
2857 free_extent_buffer(log->node);
2860 if (found_key.offset == 0)
2863 btrfs_release_path(log_root_tree, path);
2865 /* step one is to pin it all, step two is to replay just inodes */
2868 wc.process_func = replay_one_buffer;
2869 wc.stage = LOG_WALK_REPLAY_INODES;
2872 /* step three is to replay everything */
2873 if (wc.stage < LOG_WALK_REPLAY_ALL) {
2878 btrfs_free_path(path);
2880 free_extent_buffer(log_root_tree->node);
2881 log_root_tree->log_root = NULL;
2882 fs_info->log_root_recovering = 0;
2884 /* step 4: commit the transaction, which also unpins the blocks */
2885 btrfs_commit_transaction(trans, fs_info->tree_root);
2887 kfree(log_root_tree);