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"
28 /* magic values for the inode_only field in btrfs_log_inode:
30 * LOG_INODE_ALL means to log everything
31 * LOG_INODE_EXISTS means to log just enough to recreate the inode
34 #define LOG_INODE_ALL 0
35 #define LOG_INODE_EXISTS 1
38 * stages for the tree walking. The first
39 * stage (0) is to only pin down the blocks we find
40 * the second stage (1) is to make sure that all the inodes
41 * we find in the log are created in the subvolume.
43 * The last stage is to deal with directories and links and extents
44 * and all the other fun semantics
46 #define LOG_WALK_PIN_ONLY 0
47 #define LOG_WALK_REPLAY_INODES 1
48 #define LOG_WALK_REPLAY_ALL 2
50 static int __btrfs_log_inode(struct btrfs_trans_handle *trans,
51 struct btrfs_root *root, struct inode *inode,
53 static int link_to_fixup_dir(struct btrfs_trans_handle *trans,
54 struct btrfs_root *root,
55 struct btrfs_path *path, u64 objectid);
58 * tree logging is a special write ahead log used to make sure that
59 * fsyncs and O_SYNCs can happen without doing full tree commits.
61 * Full tree commits are expensive because they require commonly
62 * modified blocks to be recowed, creating many dirty pages in the
63 * extent tree an 4x-6x higher write load than ext3.
65 * Instead of doing a tree commit on every fsync, we use the
66 * key ranges and transaction ids to find items for a given file or directory
67 * that have changed in this transaction. Those items are copied into
68 * a special tree (one per subvolume root), that tree is written to disk
69 * and then the fsync is considered complete.
71 * After a crash, items are copied out of the log-tree back into the
72 * subvolume tree. Any file data extents found are recorded in the extent
73 * allocation tree, and the log-tree freed.
75 * The log tree is read three times, once to pin down all the extents it is
76 * using in ram and once, once to create all the inodes logged in the tree
77 * and once to do all the other items.
81 * btrfs_add_log_tree adds a new per-subvolume log tree into the
82 * tree of log tree roots. This must be called with a tree log transaction
83 * running (see start_log_trans).
85 static int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
86 struct btrfs_root *root)
89 struct btrfs_root_item root_item;
90 struct btrfs_inode_item *inode_item;
91 struct extent_buffer *leaf;
92 struct btrfs_root *new_root = root;
94 u64 objectid = root->root_key.objectid;
96 leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 0,
97 BTRFS_TREE_LOG_OBJECTID,
98 trans->transid, 0, 0, 0);
104 btrfs_set_header_nritems(leaf, 0);
105 btrfs_set_header_level(leaf, 0);
106 btrfs_set_header_bytenr(leaf, leaf->start);
107 btrfs_set_header_generation(leaf, trans->transid);
108 btrfs_set_header_owner(leaf, BTRFS_TREE_LOG_OBJECTID);
110 write_extent_buffer(leaf, root->fs_info->fsid,
111 (unsigned long)btrfs_header_fsid(leaf),
113 btrfs_mark_buffer_dirty(leaf);
115 inode_item = &root_item.inode;
116 memset(inode_item, 0, sizeof(*inode_item));
117 inode_item->generation = cpu_to_le64(1);
118 inode_item->size = cpu_to_le64(3);
119 inode_item->nlink = cpu_to_le32(1);
120 inode_item->nbytes = cpu_to_le64(root->leafsize);
121 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
123 btrfs_set_root_bytenr(&root_item, leaf->start);
124 btrfs_set_root_generation(&root_item, trans->transid);
125 btrfs_set_root_level(&root_item, 0);
126 btrfs_set_root_refs(&root_item, 0);
127 btrfs_set_root_used(&root_item, 0);
129 memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
130 root_item.drop_level = 0;
132 btrfs_tree_unlock(leaf);
133 free_extent_buffer(leaf);
136 btrfs_set_root_dirid(&root_item, 0);
138 key.objectid = BTRFS_TREE_LOG_OBJECTID;
139 key.offset = objectid;
140 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
141 ret = btrfs_insert_root(trans, root->fs_info->log_root_tree, &key,
146 new_root = btrfs_read_fs_root_no_radix(root->fs_info->log_root_tree,
150 WARN_ON(root->log_root);
151 root->log_root = new_root;
154 * log trees do not get reference counted because they go away
155 * before a real commit is actually done. They do store pointers
156 * to file data extents, and those reference counts still get
157 * updated (along with back refs to the log tree).
159 new_root->ref_cows = 0;
160 new_root->last_trans = trans->transid;
166 * start a sub transaction and setup the log tree
167 * this increments the log tree writer count to make the people
168 * syncing the tree wait for us to finish
170 static int start_log_trans(struct btrfs_trans_handle *trans,
171 struct btrfs_root *root)
174 mutex_lock(&root->fs_info->tree_log_mutex);
175 if (!root->fs_info->log_root_tree) {
176 ret = btrfs_init_log_root_tree(trans, root->fs_info);
179 if (!root->log_root) {
180 ret = btrfs_add_log_tree(trans, root);
183 atomic_inc(&root->fs_info->tree_log_writers);
184 root->fs_info->tree_log_batch++;
185 mutex_unlock(&root->fs_info->tree_log_mutex);
190 * returns 0 if there was a log transaction running and we were able
191 * to join, or returns -ENOENT if there were not transactions
194 static int join_running_log_trans(struct btrfs_root *root)
202 mutex_lock(&root->fs_info->tree_log_mutex);
203 if (root->log_root) {
205 atomic_inc(&root->fs_info->tree_log_writers);
206 root->fs_info->tree_log_batch++;
208 mutex_unlock(&root->fs_info->tree_log_mutex);
213 * indicate we're done making changes to the log tree
214 * and wake up anyone waiting to do a sync
216 static int end_log_trans(struct btrfs_root *root)
218 atomic_dec(&root->fs_info->tree_log_writers);
220 if (waitqueue_active(&root->fs_info->tree_log_wait))
221 wake_up(&root->fs_info->tree_log_wait);
227 * the walk control struct is used to pass state down the chain when
228 * processing the log tree. The stage field tells us which part
229 * of the log tree processing we are currently doing. The others
230 * are state fields used for that specific part
232 struct walk_control {
233 /* should we free the extent on disk when done? This is used
234 * at transaction commit time while freeing a log tree
238 /* should we write out the extent buffer? This is used
239 * while flushing the log tree to disk during a sync
243 /* should we wait for the extent buffer io to finish? Also used
244 * while flushing the log tree to disk for a sync
248 /* pin only walk, we record which extents on disk belong to the
253 /* what stage of the replay code we're currently in */
256 /* the root we are currently replaying */
257 struct btrfs_root *replay_dest;
259 /* the trans handle for the current replay */
260 struct btrfs_trans_handle *trans;
262 /* the function that gets used to process blocks we find in the
263 * tree. Note the extent_buffer might not be up to date when it is
264 * passed in, and it must be checked or read if you need the data
267 int (*process_func)(struct btrfs_root *log, struct extent_buffer *eb,
268 struct walk_control *wc, u64 gen);
272 * process_func used to pin down extents, write them or wait on them
274 static int process_one_buffer(struct btrfs_root *log,
275 struct extent_buffer *eb,
276 struct walk_control *wc, u64 gen)
279 mutex_lock(&log->fs_info->pinned_mutex);
280 btrfs_update_pinned_extents(log->fs_info->extent_root,
281 eb->start, eb->len, 1);
282 mutex_unlock(&log->fs_info->pinned_mutex);
285 if (btrfs_buffer_uptodate(eb, gen)) {
287 btrfs_write_tree_block(eb);
289 btrfs_wait_tree_block_writeback(eb);
295 * Item overwrite used by replay and tree logging. eb, slot and key all refer
296 * to the src data we are copying out.
298 * root is the tree we are copying into, and path is a scratch
299 * path for use in this function (it should be released on entry and
300 * will be released on exit).
302 * If the key is already in the destination tree the existing item is
303 * overwritten. If the existing item isn't big enough, it is extended.
304 * If it is too large, it is truncated.
306 * If the key isn't in the destination yet, a new item is inserted.
308 static noinline int overwrite_item(struct btrfs_trans_handle *trans,
309 struct btrfs_root *root,
310 struct btrfs_path *path,
311 struct extent_buffer *eb, int slot,
312 struct btrfs_key *key)
316 u64 saved_i_size = 0;
317 int save_old_i_size = 0;
318 unsigned long src_ptr;
319 unsigned long dst_ptr;
320 int overwrite_root = 0;
322 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID)
325 item_size = btrfs_item_size_nr(eb, slot);
326 src_ptr = btrfs_item_ptr_offset(eb, slot);
328 /* look for the key in the destination tree */
329 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
333 u32 dst_size = btrfs_item_size_nr(path->nodes[0],
335 if (dst_size != item_size)
338 if (item_size == 0) {
339 btrfs_release_path(root, path);
342 dst_copy = kmalloc(item_size, GFP_NOFS);
343 src_copy = kmalloc(item_size, GFP_NOFS);
345 read_extent_buffer(eb, src_copy, src_ptr, item_size);
347 dst_ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
348 read_extent_buffer(path->nodes[0], dst_copy, dst_ptr,
350 ret = memcmp(dst_copy, src_copy, item_size);
355 * they have the same contents, just return, this saves
356 * us from cowing blocks in the destination tree and doing
357 * extra writes that may not have been done by a previous
361 btrfs_release_path(root, path);
367 btrfs_release_path(root, path);
368 /* try to insert the key into the destination tree */
369 ret = btrfs_insert_empty_item(trans, root, path,
372 /* make sure any existing item is the correct size */
373 if (ret == -EEXIST) {
375 found_size = btrfs_item_size_nr(path->nodes[0],
377 if (found_size > item_size) {
378 btrfs_truncate_item(trans, root, path, item_size, 1);
379 } else if (found_size < item_size) {
380 ret = btrfs_extend_item(trans, root, path,
381 item_size - found_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 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
446 struct btrfs_key ins;
447 ins.objectid = btrfs_file_extent_disk_bytenr(
449 ins.offset = btrfs_file_extent_disk_num_bytes(
451 ins.type = BTRFS_EXTENT_ITEM_KEY;
454 * is this extent already allocated in the extent
455 * allocation tree? If so, just add a reference
457 ret = btrfs_lookup_extent(root, ins.objectid,
460 ret = btrfs_inc_extent_ref(trans, root,
461 ins.objectid, ins.offset,
462 path->nodes[0]->start,
463 root->root_key.objectid,
464 trans->transid, key->objectid);
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 found_type == BTRFS_FILE_EXTENT_PREALLOC)
543 extent_end = start + btrfs_file_extent_num_bytes(eb, item);
544 else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
545 size = btrfs_file_extent_inline_len(eb, item);
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,
567 (found_type == BTRFS_FILE_EXTENT_REG ||
568 found_type == BTRFS_FILE_EXTENT_PREALLOC)) {
569 struct btrfs_file_extent_item cmp1;
570 struct btrfs_file_extent_item cmp2;
571 struct btrfs_file_extent_item *existing;
572 struct extent_buffer *leaf;
574 leaf = path->nodes[0];
575 existing = btrfs_item_ptr(leaf, path->slots[0],
576 struct btrfs_file_extent_item);
578 read_extent_buffer(eb, &cmp1, (unsigned long)item,
580 read_extent_buffer(leaf, &cmp2, (unsigned long)existing,
584 * we already have a pointer to this exact extent,
585 * we don't have to do anything
587 if (memcmp(&cmp1, &cmp2, sizeof(cmp1)) == 0) {
588 btrfs_release_path(root, path);
592 btrfs_release_path(root, path);
594 /* drop any overlapping extents */
595 ret = btrfs_drop_extents(trans, root, inode,
596 start, extent_end, start, &alloc_hint);
599 /* insert the extent */
600 ret = overwrite_item(trans, root, path, eb, slot, key);
603 /* btrfs_drop_extents changes i_bytes & i_blocks, update it here */
604 inode_add_bytes(inode, extent_end - start);
605 btrfs_update_inode(trans, root, inode);
613 * when cleaning up conflicts between the directory names in the
614 * subvolume, directory names in the log and directory names in the
615 * inode back references, we may have to unlink inodes from directories.
617 * This is a helper function to do the unlink of a specific directory
620 static noinline int drop_one_dir_item(struct btrfs_trans_handle *trans,
621 struct btrfs_root *root,
622 struct btrfs_path *path,
624 struct btrfs_dir_item *di)
629 struct extent_buffer *leaf;
630 struct btrfs_key location;
633 leaf = path->nodes[0];
635 btrfs_dir_item_key_to_cpu(leaf, di, &location);
636 name_len = btrfs_dir_name_len(leaf, di);
637 name = kmalloc(name_len, GFP_NOFS);
638 read_extent_buffer(leaf, name, (unsigned long)(di + 1), name_len);
639 btrfs_release_path(root, path);
641 inode = read_one_inode(root, location.objectid);
644 ret = link_to_fixup_dir(trans, root, path, location.objectid);
646 ret = btrfs_unlink_inode(trans, root, dir, inode, name, name_len);
655 * helper function to see if a given name and sequence number found
656 * in an inode back reference are already in a directory and correctly
657 * point to this inode
659 static noinline int inode_in_dir(struct btrfs_root *root,
660 struct btrfs_path *path,
661 u64 dirid, u64 objectid, u64 index,
662 const char *name, int name_len)
664 struct btrfs_dir_item *di;
665 struct btrfs_key location;
668 di = btrfs_lookup_dir_index_item(NULL, root, path, dirid,
669 index, name, name_len, 0);
670 if (di && !IS_ERR(di)) {
671 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location);
672 if (location.objectid != objectid)
676 btrfs_release_path(root, path);
678 di = btrfs_lookup_dir_item(NULL, root, path, dirid, name, name_len, 0);
679 if (di && !IS_ERR(di)) {
680 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location);
681 if (location.objectid != objectid)
687 btrfs_release_path(root, path);
692 * helper function to check a log tree for a named back reference in
693 * an inode. This is used to decide if a back reference that is
694 * found in the subvolume conflicts with what we find in the log.
696 * inode backreferences may have multiple refs in a single item,
697 * during replay we process one reference at a time, and we don't
698 * want to delete valid links to a file from the subvolume if that
699 * link is also in the log.
701 static noinline int backref_in_log(struct btrfs_root *log,
702 struct btrfs_key *key,
703 char *name, int namelen)
705 struct btrfs_path *path;
706 struct btrfs_inode_ref *ref;
708 unsigned long ptr_end;
709 unsigned long name_ptr;
715 path = btrfs_alloc_path();
716 ret = btrfs_search_slot(NULL, log, key, path, 0, 0);
720 item_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]);
721 ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
722 ptr_end = ptr + item_size;
723 while (ptr < ptr_end) {
724 ref = (struct btrfs_inode_ref *)ptr;
725 found_name_len = btrfs_inode_ref_name_len(path->nodes[0], ref);
726 if (found_name_len == namelen) {
727 name_ptr = (unsigned long)(ref + 1);
728 ret = memcmp_extent_buffer(path->nodes[0], name,
735 ptr = (unsigned long)(ref + 1) + found_name_len;
738 btrfs_free_path(path);
744 * replay one inode back reference item found in the log tree.
745 * eb, slot and key refer to the buffer and key found in the log tree.
746 * root is the destination we are replaying into, and path is for temp
747 * use by this function. (it should be released on return).
749 static noinline int add_inode_ref(struct btrfs_trans_handle *trans,
750 struct btrfs_root *root,
751 struct btrfs_root *log,
752 struct btrfs_path *path,
753 struct extent_buffer *eb, int slot,
754 struct btrfs_key *key)
758 struct btrfs_key location;
759 struct btrfs_inode_ref *ref;
760 struct btrfs_dir_item *di;
764 unsigned long ref_ptr;
765 unsigned long ref_end;
767 location.objectid = key->objectid;
768 location.type = BTRFS_INODE_ITEM_KEY;
772 * it is possible that we didn't log all the parent directories
773 * for a given inode. If we don't find the dir, just don't
774 * copy the back ref in. The link count fixup code will take
777 dir = read_one_inode(root, key->offset);
781 inode = read_one_inode(root, key->objectid);
784 ref_ptr = btrfs_item_ptr_offset(eb, slot);
785 ref_end = ref_ptr + btrfs_item_size_nr(eb, slot);
788 ref = (struct btrfs_inode_ref *)ref_ptr;
790 namelen = btrfs_inode_ref_name_len(eb, ref);
791 name = kmalloc(namelen, GFP_NOFS);
794 read_extent_buffer(eb, name, (unsigned long)(ref + 1), namelen);
796 /* if we already have a perfect match, we're done */
797 if (inode_in_dir(root, path, dir->i_ino, inode->i_ino,
798 btrfs_inode_ref_index(eb, ref),
804 * look for a conflicting back reference in the metadata.
805 * if we find one we have to unlink that name of the file
806 * before we add our new link. Later on, we overwrite any
807 * existing back reference, and we don't want to create
808 * dangling pointers in the directory.
811 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
815 struct btrfs_inode_ref *victim_ref;
817 unsigned long ptr_end;
818 struct extent_buffer *leaf = path->nodes[0];
820 /* are we trying to overwrite a back ref for the root directory
821 * if so, just jump out, we're done
823 if (key->objectid == key->offset)
826 /* check all the names in this back reference to see
827 * if they are in the log. if so, we allow them to stay
828 * otherwise they must be unlinked as a conflict
830 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
831 ptr_end = ptr + btrfs_item_size_nr(leaf, path->slots[0]);
832 while (ptr < ptr_end) {
833 victim_ref = (struct btrfs_inode_ref *)ptr;
834 victim_name_len = btrfs_inode_ref_name_len(leaf,
836 victim_name = kmalloc(victim_name_len, GFP_NOFS);
837 BUG_ON(!victim_name);
839 read_extent_buffer(leaf, victim_name,
840 (unsigned long)(victim_ref + 1),
843 if (!backref_in_log(log, key, victim_name,
845 btrfs_inc_nlink(inode);
846 btrfs_release_path(root, path);
847 ret = btrfs_unlink_inode(trans, root, dir,
851 btrfs_release_path(root, path);
855 ptr = (unsigned long)(victim_ref + 1) + victim_name_len;
859 btrfs_release_path(root, path);
861 /* look for a conflicting sequence number */
862 di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
863 btrfs_inode_ref_index(eb, ref),
865 if (di && !IS_ERR(di)) {
866 ret = drop_one_dir_item(trans, root, path, dir, di);
869 btrfs_release_path(root, path);
872 /* look for a conflicting name */
873 di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
875 if (di && !IS_ERR(di)) {
876 ret = drop_one_dir_item(trans, root, path, dir, di);
879 btrfs_release_path(root, path);
881 /* insert our name */
882 ret = btrfs_add_link(trans, dir, inode, name, namelen, 0,
883 btrfs_inode_ref_index(eb, ref));
886 btrfs_update_inode(trans, root, inode);
889 ref_ptr = (unsigned long)(ref + 1) + namelen;
891 if (ref_ptr < ref_end)
894 /* finally write the back reference in the inode */
895 ret = overwrite_item(trans, root, path, eb, slot, key);
899 btrfs_release_path(root, path);
906 * replay one csum item from the log tree into the subvolume 'root'
907 * eb, slot and key all refer to the log tree
908 * path is for temp use by this function and should be released on return
910 * This copies the checksums out of the log tree and inserts them into
911 * the subvolume. Any existing checksums for this range in the file
912 * are overwritten, and new items are added where required.
914 * We keep this simple by reusing the btrfs_ordered_sum code from
915 * the data=ordered mode. This basically means making a copy
916 * of all the checksums in ram, which we have to do anyway for kmap
919 * The copy is then sent down to btrfs_csum_file_blocks, which
920 * does all the hard work of finding existing items in the file
921 * or adding new ones.
923 static noinline int replay_one_csum(struct btrfs_trans_handle *trans,
924 struct btrfs_root *root,
925 struct btrfs_path *path,
926 struct extent_buffer *eb, int slot,
927 struct btrfs_key *key)
930 u32 item_size = btrfs_item_size_nr(eb, slot);
933 btrfs_super_csum_size(&root->fs_info->super_copy);
934 unsigned long file_bytes;
935 struct btrfs_ordered_sum *sums;
936 struct btrfs_sector_sum *sector_sum;
939 file_bytes = (item_size / csum_size) * root->sectorsize;
940 sums = kzalloc(btrfs_ordered_sum_size(root, file_bytes), GFP_NOFS);
944 INIT_LIST_HEAD(&sums->list);
945 sums->len = file_bytes;
946 sums->bytenr = 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->bytenr = cur_offset;
956 read_extent_buffer(eb, §or_sum->sum, ptr, csum_size);
958 item_size -= csum_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->fs_info->csum_root, sums);
970 * There are a few corners where the link count of the file can't
971 * be properly maintained during replay. So, instead of adding
972 * lots of complexity to the log code, we just scan the backrefs
973 * for any file that has been through replay.
975 * The scan will update the link count on the inode to reflect the
976 * number of back refs found. If it goes down to zero, the iput
977 * will free the inode.
979 static noinline int fixup_inode_link_count(struct btrfs_trans_handle *trans,
980 struct btrfs_root *root,
983 struct btrfs_path *path;
985 struct btrfs_key key;
988 unsigned long ptr_end;
991 key.objectid = inode->i_ino;
992 key.type = BTRFS_INODE_REF_KEY;
993 key.offset = (u64)-1;
995 path = btrfs_alloc_path();
998 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1002 if (path->slots[0] == 0)
1006 btrfs_item_key_to_cpu(path->nodes[0], &key,
1008 if (key.objectid != inode->i_ino ||
1009 key.type != BTRFS_INODE_REF_KEY)
1011 ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
1012 ptr_end = ptr + btrfs_item_size_nr(path->nodes[0],
1014 while (ptr < ptr_end) {
1015 struct btrfs_inode_ref *ref;
1017 ref = (struct btrfs_inode_ref *)ptr;
1018 name_len = btrfs_inode_ref_name_len(path->nodes[0],
1020 ptr = (unsigned long)(ref + 1) + name_len;
1024 if (key.offset == 0)
1027 btrfs_release_path(root, path);
1029 btrfs_free_path(path);
1030 if (nlink != inode->i_nlink) {
1031 inode->i_nlink = nlink;
1032 btrfs_update_inode(trans, root, inode);
1034 BTRFS_I(inode)->index_cnt = (u64)-1;
1039 static noinline int fixup_inode_link_counts(struct btrfs_trans_handle *trans,
1040 struct btrfs_root *root,
1041 struct btrfs_path *path)
1044 struct btrfs_key key;
1045 struct inode *inode;
1047 key.objectid = BTRFS_TREE_LOG_FIXUP_OBJECTID;
1048 key.type = BTRFS_ORPHAN_ITEM_KEY;
1049 key.offset = (u64)-1;
1051 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1056 if (path->slots[0] == 0)
1061 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1062 if (key.objectid != BTRFS_TREE_LOG_FIXUP_OBJECTID ||
1063 key.type != BTRFS_ORPHAN_ITEM_KEY)
1066 ret = btrfs_del_item(trans, root, path);
1069 btrfs_release_path(root, path);
1070 inode = read_one_inode(root, key.offset);
1073 ret = fixup_inode_link_count(trans, root, inode);
1078 if (key.offset == 0)
1082 btrfs_release_path(root, path);
1088 * record a given inode in the fixup dir so we can check its link
1089 * count when replay is done. The link count is incremented here
1090 * so the inode won't go away until we check it
1092 static noinline int link_to_fixup_dir(struct btrfs_trans_handle *trans,
1093 struct btrfs_root *root,
1094 struct btrfs_path *path,
1097 struct btrfs_key key;
1099 struct inode *inode;
1101 inode = read_one_inode(root, objectid);
1104 key.objectid = BTRFS_TREE_LOG_FIXUP_OBJECTID;
1105 btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
1106 key.offset = objectid;
1108 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1110 btrfs_release_path(root, path);
1112 btrfs_inc_nlink(inode);
1113 btrfs_update_inode(trans, root, inode);
1114 } else if (ret == -EEXIST) {
1125 * when replaying the log for a directory, we only insert names
1126 * for inodes that actually exist. This means an fsync on a directory
1127 * does not implicitly fsync all the new files in it
1129 static noinline int insert_one_name(struct btrfs_trans_handle *trans,
1130 struct btrfs_root *root,
1131 struct btrfs_path *path,
1132 u64 dirid, u64 index,
1133 char *name, int name_len, u8 type,
1134 struct btrfs_key *location)
1136 struct inode *inode;
1140 inode = read_one_inode(root, location->objectid);
1144 dir = read_one_inode(root, dirid);
1149 ret = btrfs_add_link(trans, dir, inode, name, name_len, 1, index);
1151 /* FIXME, put inode into FIXUP list */
1159 * take a single entry in a log directory item and replay it into
1162 * if a conflicting item exists in the subdirectory already,
1163 * the inode it points to is unlinked and put into the link count
1166 * If a name from the log points to a file or directory that does
1167 * not exist in the FS, it is skipped. fsyncs on directories
1168 * do not force down inodes inside that directory, just changes to the
1169 * names or unlinks in a directory.
1171 static noinline int replay_one_name(struct btrfs_trans_handle *trans,
1172 struct btrfs_root *root,
1173 struct btrfs_path *path,
1174 struct extent_buffer *eb,
1175 struct btrfs_dir_item *di,
1176 struct btrfs_key *key)
1180 struct btrfs_dir_item *dst_di;
1181 struct btrfs_key found_key;
1182 struct btrfs_key log_key;
1188 dir = read_one_inode(root, key->objectid);
1191 name_len = btrfs_dir_name_len(eb, di);
1192 name = kmalloc(name_len, GFP_NOFS);
1193 log_type = btrfs_dir_type(eb, di);
1194 read_extent_buffer(eb, name, (unsigned long)(di + 1),
1197 btrfs_dir_item_key_to_cpu(eb, di, &log_key);
1198 exists = btrfs_lookup_inode(trans, root, path, &log_key, 0);
1203 btrfs_release_path(root, path);
1205 if (key->type == BTRFS_DIR_ITEM_KEY) {
1206 dst_di = btrfs_lookup_dir_item(trans, root, path, key->objectid,
1208 } else if (key->type == BTRFS_DIR_INDEX_KEY) {
1209 dst_di = btrfs_lookup_dir_index_item(trans, root, path,
1216 if (!dst_di || IS_ERR(dst_di)) {
1217 /* we need a sequence number to insert, so we only
1218 * do inserts for the BTRFS_DIR_INDEX_KEY types
1220 if (key->type != BTRFS_DIR_INDEX_KEY)
1225 btrfs_dir_item_key_to_cpu(path->nodes[0], dst_di, &found_key);
1226 /* the existing item matches the logged item */
1227 if (found_key.objectid == log_key.objectid &&
1228 found_key.type == log_key.type &&
1229 found_key.offset == log_key.offset &&
1230 btrfs_dir_type(path->nodes[0], dst_di) == log_type) {
1235 * don't drop the conflicting directory entry if the inode
1236 * for the new entry doesn't exist
1241 ret = drop_one_dir_item(trans, root, path, dir, dst_di);
1244 if (key->type == BTRFS_DIR_INDEX_KEY)
1247 btrfs_release_path(root, path);
1253 btrfs_release_path(root, path);
1254 ret = insert_one_name(trans, root, path, key->objectid, key->offset,
1255 name, name_len, log_type, &log_key);
1257 if (ret && ret != -ENOENT)
1263 * find all the names in a directory item and reconcile them into
1264 * the subvolume. Only BTRFS_DIR_ITEM_KEY types will have more than
1265 * one name in a directory item, but the same code gets used for
1266 * both directory index types
1268 static noinline int replay_one_dir_item(struct btrfs_trans_handle *trans,
1269 struct btrfs_root *root,
1270 struct btrfs_path *path,
1271 struct extent_buffer *eb, int slot,
1272 struct btrfs_key *key)
1275 u32 item_size = btrfs_item_size_nr(eb, slot);
1276 struct btrfs_dir_item *di;
1279 unsigned long ptr_end;
1281 ptr = btrfs_item_ptr_offset(eb, slot);
1282 ptr_end = ptr + item_size;
1283 while (ptr < ptr_end) {
1284 di = (struct btrfs_dir_item *)ptr;
1285 name_len = btrfs_dir_name_len(eb, di);
1286 ret = replay_one_name(trans, root, path, eb, di, key);
1288 ptr = (unsigned long)(di + 1);
1295 * directory replay has two parts. There are the standard directory
1296 * items in the log copied from the subvolume, and range items
1297 * created in the log while the subvolume was logged.
1299 * The range items tell us which parts of the key space the log
1300 * is authoritative for. During replay, if a key in the subvolume
1301 * directory is in a logged range item, but not actually in the log
1302 * that means it was deleted from the directory before the fsync
1303 * and should be removed.
1305 static noinline int find_dir_range(struct btrfs_root *root,
1306 struct btrfs_path *path,
1307 u64 dirid, int key_type,
1308 u64 *start_ret, u64 *end_ret)
1310 struct btrfs_key key;
1312 struct btrfs_dir_log_item *item;
1316 if (*start_ret == (u64)-1)
1319 key.objectid = dirid;
1320 key.type = key_type;
1321 key.offset = *start_ret;
1323 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1327 if (path->slots[0] == 0)
1332 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1334 if (key.type != key_type || key.objectid != dirid) {
1338 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
1339 struct btrfs_dir_log_item);
1340 found_end = btrfs_dir_log_end(path->nodes[0], item);
1342 if (*start_ret >= key.offset && *start_ret <= found_end) {
1344 *start_ret = key.offset;
1345 *end_ret = found_end;
1350 /* check the next slot in the tree to see if it is a valid item */
1351 nritems = btrfs_header_nritems(path->nodes[0]);
1352 if (path->slots[0] >= nritems) {
1353 ret = btrfs_next_leaf(root, path);
1360 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1362 if (key.type != key_type || key.objectid != dirid) {
1366 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
1367 struct btrfs_dir_log_item);
1368 found_end = btrfs_dir_log_end(path->nodes[0], item);
1369 *start_ret = key.offset;
1370 *end_ret = found_end;
1373 btrfs_release_path(root, path);
1378 * this looks for a given directory item in the log. If the directory
1379 * item is not in the log, the item is removed and the inode it points
1382 static noinline int check_item_in_log(struct btrfs_trans_handle *trans,
1383 struct btrfs_root *root,
1384 struct btrfs_root *log,
1385 struct btrfs_path *path,
1386 struct btrfs_path *log_path,
1388 struct btrfs_key *dir_key)
1391 struct extent_buffer *eb;
1394 struct btrfs_dir_item *di;
1395 struct btrfs_dir_item *log_di;
1398 unsigned long ptr_end;
1400 struct inode *inode;
1401 struct btrfs_key location;
1404 eb = path->nodes[0];
1405 slot = path->slots[0];
1406 item_size = btrfs_item_size_nr(eb, slot);
1407 ptr = btrfs_item_ptr_offset(eb, slot);
1408 ptr_end = ptr + item_size;
1409 while (ptr < ptr_end) {
1410 di = (struct btrfs_dir_item *)ptr;
1411 name_len = btrfs_dir_name_len(eb, di);
1412 name = kmalloc(name_len, GFP_NOFS);
1417 read_extent_buffer(eb, name, (unsigned long)(di + 1),
1420 if (dir_key->type == BTRFS_DIR_ITEM_KEY) {
1421 log_di = btrfs_lookup_dir_item(trans, log, log_path,
1424 } else if (dir_key->type == BTRFS_DIR_INDEX_KEY) {
1425 log_di = btrfs_lookup_dir_index_item(trans, log,
1431 if (!log_di || IS_ERR(log_di)) {
1432 btrfs_dir_item_key_to_cpu(eb, di, &location);
1433 btrfs_release_path(root, path);
1434 btrfs_release_path(log, log_path);
1435 inode = read_one_inode(root, location.objectid);
1438 ret = link_to_fixup_dir(trans, root,
1439 path, location.objectid);
1441 btrfs_inc_nlink(inode);
1442 ret = btrfs_unlink_inode(trans, root, dir, inode,
1448 /* there might still be more names under this key
1449 * check and repeat if required
1451 ret = btrfs_search_slot(NULL, root, dir_key, path,
1458 btrfs_release_path(log, log_path);
1461 ptr = (unsigned long)(di + 1);
1466 btrfs_release_path(root, path);
1467 btrfs_release_path(log, log_path);
1472 * deletion replay happens before we copy any new directory items
1473 * out of the log or out of backreferences from inodes. It
1474 * scans the log to find ranges of keys that log is authoritative for,
1475 * and then scans the directory to find items in those ranges that are
1476 * not present in the log.
1478 * Anything we don't find in the log is unlinked and removed from the
1481 static noinline int replay_dir_deletes(struct btrfs_trans_handle *trans,
1482 struct btrfs_root *root,
1483 struct btrfs_root *log,
1484 struct btrfs_path *path,
1489 int key_type = BTRFS_DIR_LOG_ITEM_KEY;
1491 struct btrfs_key dir_key;
1492 struct btrfs_key found_key;
1493 struct btrfs_path *log_path;
1496 dir_key.objectid = dirid;
1497 dir_key.type = BTRFS_DIR_ITEM_KEY;
1498 log_path = btrfs_alloc_path();
1502 dir = read_one_inode(root, dirid);
1503 /* it isn't an error if the inode isn't there, that can happen
1504 * because we replay the deletes before we copy in the inode item
1508 btrfs_free_path(log_path);
1515 ret = find_dir_range(log, path, dirid, key_type,
1516 &range_start, &range_end);
1520 dir_key.offset = range_start;
1523 ret = btrfs_search_slot(NULL, root, &dir_key, path,
1528 nritems = btrfs_header_nritems(path->nodes[0]);
1529 if (path->slots[0] >= nritems) {
1530 ret = btrfs_next_leaf(root, path);
1534 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1536 if (found_key.objectid != dirid ||
1537 found_key.type != dir_key.type)
1540 if (found_key.offset > range_end)
1543 ret = check_item_in_log(trans, root, log, path,
1544 log_path, dir, &found_key);
1546 if (found_key.offset == (u64)-1)
1548 dir_key.offset = found_key.offset + 1;
1550 btrfs_release_path(root, path);
1551 if (range_end == (u64)-1)
1553 range_start = range_end + 1;
1558 if (key_type == BTRFS_DIR_LOG_ITEM_KEY) {
1559 key_type = BTRFS_DIR_LOG_INDEX_KEY;
1560 dir_key.type = BTRFS_DIR_INDEX_KEY;
1561 btrfs_release_path(root, path);
1565 btrfs_release_path(root, path);
1566 btrfs_free_path(log_path);
1572 * the process_func used to replay items from the log tree. This
1573 * gets called in two different stages. The first stage just looks
1574 * for inodes and makes sure they are all copied into the subvolume.
1576 * The second stage copies all the other item types from the log into
1577 * the subvolume. The two stage approach is slower, but gets rid of
1578 * lots of complexity around inodes referencing other inodes that exist
1579 * only in the log (references come from either directory items or inode
1582 static int replay_one_buffer(struct btrfs_root *log, struct extent_buffer *eb,
1583 struct walk_control *wc, u64 gen)
1586 struct btrfs_path *path;
1587 struct btrfs_root *root = wc->replay_dest;
1588 struct btrfs_key key;
1594 btrfs_read_buffer(eb, gen);
1596 level = btrfs_header_level(eb);
1601 path = btrfs_alloc_path();
1604 nritems = btrfs_header_nritems(eb);
1605 for (i = 0; i < nritems; i++) {
1606 btrfs_item_key_to_cpu(eb, &key, i);
1607 item_size = btrfs_item_size_nr(eb, i);
1609 /* inode keys are done during the first stage */
1610 if (key.type == BTRFS_INODE_ITEM_KEY &&
1611 wc->stage == LOG_WALK_REPLAY_INODES) {
1612 struct inode *inode;
1613 struct btrfs_inode_item *inode_item;
1616 inode_item = btrfs_item_ptr(eb, i,
1617 struct btrfs_inode_item);
1618 mode = btrfs_inode_mode(eb, inode_item);
1619 if (S_ISDIR(mode)) {
1620 ret = replay_dir_deletes(wc->trans,
1621 root, log, path, key.objectid);
1624 ret = overwrite_item(wc->trans, root, path,
1628 /* for regular files, truncate away
1629 * extents past the new EOF
1631 if (S_ISREG(mode)) {
1632 inode = read_one_inode(root,
1636 ret = btrfs_truncate_inode_items(wc->trans,
1637 root, inode, inode->i_size,
1638 BTRFS_EXTENT_DATA_KEY);
1642 ret = link_to_fixup_dir(wc->trans, root,
1643 path, key.objectid);
1646 if (wc->stage < LOG_WALK_REPLAY_ALL)
1649 /* these keys are simply copied */
1650 if (key.type == BTRFS_XATTR_ITEM_KEY) {
1651 ret = overwrite_item(wc->trans, root, path,
1654 } else if (key.type == BTRFS_INODE_REF_KEY) {
1655 ret = add_inode_ref(wc->trans, root, log, path,
1657 BUG_ON(ret && ret != -ENOENT);
1658 } else if (key.type == BTRFS_EXTENT_DATA_KEY) {
1659 ret = replay_one_extent(wc->trans, root, path,
1662 } else if (key.type == BTRFS_EXTENT_CSUM_KEY) {
1663 ret = replay_one_csum(wc->trans, root, path,
1666 } else if (key.type == BTRFS_DIR_ITEM_KEY ||
1667 key.type == BTRFS_DIR_INDEX_KEY) {
1668 ret = replay_one_dir_item(wc->trans, root, path,
1673 btrfs_free_path(path);
1677 static noinline int walk_down_log_tree(struct btrfs_trans_handle *trans,
1678 struct btrfs_root *root,
1679 struct btrfs_path *path, int *level,
1680 struct walk_control *wc)
1686 struct extent_buffer *next;
1687 struct extent_buffer *cur;
1688 struct extent_buffer *parent;
1692 WARN_ON(*level < 0);
1693 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1695 while (*level > 0) {
1696 WARN_ON(*level < 0);
1697 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1698 cur = path->nodes[*level];
1700 if (btrfs_header_level(cur) != *level)
1703 if (path->slots[*level] >=
1704 btrfs_header_nritems(cur))
1707 bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
1708 ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
1709 blocksize = btrfs_level_size(root, *level - 1);
1711 parent = path->nodes[*level];
1712 root_owner = btrfs_header_owner(parent);
1713 root_gen = btrfs_header_generation(parent);
1715 next = btrfs_find_create_tree_block(root, bytenr, blocksize);
1717 wc->process_func(root, next, wc, ptr_gen);
1720 path->slots[*level]++;
1722 btrfs_read_buffer(next, ptr_gen);
1724 btrfs_tree_lock(next);
1725 clean_tree_block(trans, root, next);
1726 btrfs_wait_tree_block_writeback(next);
1727 btrfs_tree_unlock(next);
1729 ret = btrfs_drop_leaf_ref(trans, root, next);
1732 WARN_ON(root_owner !=
1733 BTRFS_TREE_LOG_OBJECTID);
1734 ret = btrfs_free_reserved_extent(root,
1738 free_extent_buffer(next);
1741 btrfs_read_buffer(next, ptr_gen);
1743 WARN_ON(*level <= 0);
1744 if (path->nodes[*level-1])
1745 free_extent_buffer(path->nodes[*level-1]);
1746 path->nodes[*level-1] = next;
1747 *level = btrfs_header_level(next);
1748 path->slots[*level] = 0;
1751 WARN_ON(*level < 0);
1752 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1754 if (path->nodes[*level] == root->node)
1755 parent = path->nodes[*level];
1757 parent = path->nodes[*level + 1];
1759 bytenr = path->nodes[*level]->start;
1761 blocksize = btrfs_level_size(root, *level);
1762 root_owner = btrfs_header_owner(parent);
1763 root_gen = btrfs_header_generation(parent);
1765 wc->process_func(root, path->nodes[*level], wc,
1766 btrfs_header_generation(path->nodes[*level]));
1769 next = path->nodes[*level];
1770 btrfs_tree_lock(next);
1771 clean_tree_block(trans, root, next);
1772 btrfs_wait_tree_block_writeback(next);
1773 btrfs_tree_unlock(next);
1776 ret = btrfs_drop_leaf_ref(trans, root, next);
1779 WARN_ON(root_owner != BTRFS_TREE_LOG_OBJECTID);
1780 ret = btrfs_free_reserved_extent(root, bytenr, blocksize);
1783 free_extent_buffer(path->nodes[*level]);
1784 path->nodes[*level] = NULL;
1791 static noinline int walk_up_log_tree(struct btrfs_trans_handle *trans,
1792 struct btrfs_root *root,
1793 struct btrfs_path *path, int *level,
1794 struct walk_control *wc)
1802 for (i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
1803 slot = path->slots[i];
1804 if (slot < btrfs_header_nritems(path->nodes[i]) - 1) {
1805 struct extent_buffer *node;
1806 node = path->nodes[i];
1809 WARN_ON(*level == 0);
1812 struct extent_buffer *parent;
1813 if (path->nodes[*level] == root->node)
1814 parent = path->nodes[*level];
1816 parent = path->nodes[*level + 1];
1818 root_owner = btrfs_header_owner(parent);
1819 root_gen = btrfs_header_generation(parent);
1820 wc->process_func(root, path->nodes[*level], wc,
1821 btrfs_header_generation(path->nodes[*level]));
1823 struct extent_buffer *next;
1825 next = path->nodes[*level];
1827 btrfs_tree_lock(next);
1828 clean_tree_block(trans, root, next);
1829 btrfs_wait_tree_block_writeback(next);
1830 btrfs_tree_unlock(next);
1833 ret = btrfs_drop_leaf_ref(trans, root,
1838 WARN_ON(root_owner != BTRFS_TREE_LOG_OBJECTID);
1839 ret = btrfs_free_reserved_extent(root,
1840 path->nodes[*level]->start,
1841 path->nodes[*level]->len);
1844 free_extent_buffer(path->nodes[*level]);
1845 path->nodes[*level] = NULL;
1853 * drop the reference count on the tree rooted at 'snap'. This traverses
1854 * the tree freeing any blocks that have a ref count of zero after being
1857 static int walk_log_tree(struct btrfs_trans_handle *trans,
1858 struct btrfs_root *log, struct walk_control *wc)
1863 struct btrfs_path *path;
1867 path = btrfs_alloc_path();
1870 level = btrfs_header_level(log->node);
1872 path->nodes[level] = log->node;
1873 extent_buffer_get(log->node);
1874 path->slots[level] = 0;
1877 wret = walk_down_log_tree(trans, log, path, &level, wc);
1883 wret = walk_up_log_tree(trans, log, path, &level, wc);
1890 /* was the root node processed? if not, catch it here */
1891 if (path->nodes[orig_level]) {
1892 wc->process_func(log, path->nodes[orig_level], wc,
1893 btrfs_header_generation(path->nodes[orig_level]));
1895 struct extent_buffer *next;
1897 next = path->nodes[orig_level];
1899 btrfs_tree_lock(next);
1900 clean_tree_block(trans, log, next);
1901 btrfs_wait_tree_block_writeback(next);
1902 btrfs_tree_unlock(next);
1904 if (orig_level == 0) {
1905 ret = btrfs_drop_leaf_ref(trans, log,
1909 WARN_ON(log->root_key.objectid !=
1910 BTRFS_TREE_LOG_OBJECTID);
1911 ret = btrfs_free_reserved_extent(log, next->start,
1917 for (i = 0; i <= orig_level; i++) {
1918 if (path->nodes[i]) {
1919 free_extent_buffer(path->nodes[i]);
1920 path->nodes[i] = NULL;
1923 btrfs_free_path(path);
1925 free_extent_buffer(log->node);
1929 static int wait_log_commit(struct btrfs_root *log)
1932 u64 transid = log->fs_info->tree_log_transid;
1935 prepare_to_wait(&log->fs_info->tree_log_wait, &wait,
1936 TASK_UNINTERRUPTIBLE);
1937 mutex_unlock(&log->fs_info->tree_log_mutex);
1938 if (atomic_read(&log->fs_info->tree_log_commit))
1940 finish_wait(&log->fs_info->tree_log_wait, &wait);
1941 mutex_lock(&log->fs_info->tree_log_mutex);
1942 } while (transid == log->fs_info->tree_log_transid &&
1943 atomic_read(&log->fs_info->tree_log_commit));
1948 * btrfs_sync_log does sends a given tree log down to the disk and
1949 * updates the super blocks to record it. When this call is done,
1950 * you know that any inodes previously logged are safely on disk
1952 int btrfs_sync_log(struct btrfs_trans_handle *trans,
1953 struct btrfs_root *root)
1956 unsigned long batch;
1957 struct btrfs_root *log = root->log_root;
1959 mutex_lock(&log->fs_info->tree_log_mutex);
1960 if (atomic_read(&log->fs_info->tree_log_commit)) {
1961 wait_log_commit(log);
1964 atomic_set(&log->fs_info->tree_log_commit, 1);
1967 batch = log->fs_info->tree_log_batch;
1968 mutex_unlock(&log->fs_info->tree_log_mutex);
1969 schedule_timeout_uninterruptible(1);
1970 mutex_lock(&log->fs_info->tree_log_mutex);
1972 while (atomic_read(&log->fs_info->tree_log_writers)) {
1974 prepare_to_wait(&log->fs_info->tree_log_wait, &wait,
1975 TASK_UNINTERRUPTIBLE);
1976 mutex_unlock(&log->fs_info->tree_log_mutex);
1977 if (atomic_read(&log->fs_info->tree_log_writers))
1979 mutex_lock(&log->fs_info->tree_log_mutex);
1980 finish_wait(&log->fs_info->tree_log_wait, &wait);
1982 if (batch == log->fs_info->tree_log_batch)
1986 ret = btrfs_write_and_wait_marked_extents(log, &log->dirty_log_pages);
1988 ret = btrfs_write_and_wait_marked_extents(root->fs_info->log_root_tree,
1989 &root->fs_info->log_root_tree->dirty_log_pages);
1992 btrfs_set_super_log_root(&root->fs_info->super_for_commit,
1993 log->fs_info->log_root_tree->node->start);
1994 btrfs_set_super_log_root_level(&root->fs_info->super_for_commit,
1995 btrfs_header_level(log->fs_info->log_root_tree->node));
1997 write_ctree_super(trans, log->fs_info->tree_root, 2);
1998 log->fs_info->tree_log_transid++;
1999 log->fs_info->tree_log_batch = 0;
2000 atomic_set(&log->fs_info->tree_log_commit, 0);
2002 if (waitqueue_active(&log->fs_info->tree_log_wait))
2003 wake_up(&log->fs_info->tree_log_wait);
2005 mutex_unlock(&log->fs_info->tree_log_mutex);
2009 /* * free all the extents used by the tree log. This should be called
2010 * at commit time of the full transaction
2012 int btrfs_free_log(struct btrfs_trans_handle *trans, struct btrfs_root *root)
2015 struct btrfs_root *log;
2019 struct walk_control wc = {
2021 .process_func = process_one_buffer
2024 if (!root->log_root)
2027 log = root->log_root;
2028 ret = walk_log_tree(trans, log, &wc);
2032 ret = find_first_extent_bit(&log->dirty_log_pages,
2033 0, &start, &end, EXTENT_DIRTY);
2037 clear_extent_dirty(&log->dirty_log_pages,
2038 start, end, GFP_NOFS);
2041 log = root->log_root;
2042 ret = btrfs_del_root(trans, root->fs_info->log_root_tree,
2045 root->log_root = NULL;
2046 kfree(root->log_root);
2051 * helper function to update the item for a given subvolumes log root
2052 * in the tree of log roots
2054 static int update_log_root(struct btrfs_trans_handle *trans,
2055 struct btrfs_root *log)
2057 u64 bytenr = btrfs_root_bytenr(&log->root_item);
2060 if (log->node->start == bytenr)
2063 btrfs_set_root_bytenr(&log->root_item, log->node->start);
2064 btrfs_set_root_generation(&log->root_item, trans->transid);
2065 btrfs_set_root_level(&log->root_item, btrfs_header_level(log->node));
2066 ret = btrfs_update_root(trans, log->fs_info->log_root_tree,
2067 &log->root_key, &log->root_item);
2073 * If both a file and directory are logged, and unlinks or renames are
2074 * mixed in, we have a few interesting corners:
2076 * create file X in dir Y
2077 * link file X to X.link in dir Y
2079 * unlink file X but leave X.link
2082 * After a crash we would expect only X.link to exist. But file X
2083 * didn't get fsync'd again so the log has back refs for X and X.link.
2085 * We solve this by removing directory entries and inode backrefs from the
2086 * log when a file that was logged in the current transaction is
2087 * unlinked. Any later fsync will include the updated log entries, and
2088 * we'll be able to reconstruct the proper directory items from backrefs.
2090 * This optimizations allows us to avoid relogging the entire inode
2091 * or the entire directory.
2093 int btrfs_del_dir_entries_in_log(struct btrfs_trans_handle *trans,
2094 struct btrfs_root *root,
2095 const char *name, int name_len,
2096 struct inode *dir, u64 index)
2098 struct btrfs_root *log;
2099 struct btrfs_dir_item *di;
2100 struct btrfs_path *path;
2104 if (BTRFS_I(dir)->logged_trans < trans->transid)
2107 ret = join_running_log_trans(root);
2111 mutex_lock(&BTRFS_I(dir)->log_mutex);
2113 log = root->log_root;
2114 path = btrfs_alloc_path();
2115 di = btrfs_lookup_dir_item(trans, log, path, dir->i_ino,
2116 name, name_len, -1);
2117 if (di && !IS_ERR(di)) {
2118 ret = btrfs_delete_one_dir_name(trans, log, path, di);
2119 bytes_del += name_len;
2122 btrfs_release_path(log, path);
2123 di = btrfs_lookup_dir_index_item(trans, log, path, dir->i_ino,
2124 index, name, name_len, -1);
2125 if (di && !IS_ERR(di)) {
2126 ret = btrfs_delete_one_dir_name(trans, log, path, di);
2127 bytes_del += name_len;
2131 /* update the directory size in the log to reflect the names
2135 struct btrfs_key key;
2137 key.objectid = dir->i_ino;
2139 key.type = BTRFS_INODE_ITEM_KEY;
2140 btrfs_release_path(log, path);
2142 ret = btrfs_search_slot(trans, log, &key, path, 0, 1);
2144 struct btrfs_inode_item *item;
2147 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2148 struct btrfs_inode_item);
2149 i_size = btrfs_inode_size(path->nodes[0], item);
2150 if (i_size > bytes_del)
2151 i_size -= bytes_del;
2154 btrfs_set_inode_size(path->nodes[0], item, i_size);
2155 btrfs_mark_buffer_dirty(path->nodes[0]);
2158 btrfs_release_path(log, path);
2161 btrfs_free_path(path);
2162 mutex_unlock(&BTRFS_I(dir)->log_mutex);
2163 end_log_trans(root);
2168 /* see comments for btrfs_del_dir_entries_in_log */
2169 int btrfs_del_inode_ref_in_log(struct btrfs_trans_handle *trans,
2170 struct btrfs_root *root,
2171 const char *name, int name_len,
2172 struct inode *inode, u64 dirid)
2174 struct btrfs_root *log;
2178 if (BTRFS_I(inode)->logged_trans < trans->transid)
2181 ret = join_running_log_trans(root);
2184 log = root->log_root;
2185 mutex_lock(&BTRFS_I(inode)->log_mutex);
2187 ret = btrfs_del_inode_ref(trans, log, name, name_len, inode->i_ino,
2189 mutex_unlock(&BTRFS_I(inode)->log_mutex);
2190 end_log_trans(root);
2196 * creates a range item in the log for 'dirid'. first_offset and
2197 * last_offset tell us which parts of the key space the log should
2198 * be considered authoritative for.
2200 static noinline int insert_dir_log_key(struct btrfs_trans_handle *trans,
2201 struct btrfs_root *log,
2202 struct btrfs_path *path,
2203 int key_type, u64 dirid,
2204 u64 first_offset, u64 last_offset)
2207 struct btrfs_key key;
2208 struct btrfs_dir_log_item *item;
2210 key.objectid = dirid;
2211 key.offset = first_offset;
2212 if (key_type == BTRFS_DIR_ITEM_KEY)
2213 key.type = BTRFS_DIR_LOG_ITEM_KEY;
2215 key.type = BTRFS_DIR_LOG_INDEX_KEY;
2216 ret = btrfs_insert_empty_item(trans, log, path, &key, sizeof(*item));
2219 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2220 struct btrfs_dir_log_item);
2221 btrfs_set_dir_log_end(path->nodes[0], item, last_offset);
2222 btrfs_mark_buffer_dirty(path->nodes[0]);
2223 btrfs_release_path(log, path);
2228 * log all the items included in the current transaction for a given
2229 * directory. This also creates the range items in the log tree required
2230 * to replay anything deleted before the fsync
2232 static noinline int log_dir_items(struct btrfs_trans_handle *trans,
2233 struct btrfs_root *root, struct inode *inode,
2234 struct btrfs_path *path,
2235 struct btrfs_path *dst_path, int key_type,
2236 u64 min_offset, u64 *last_offset_ret)
2238 struct btrfs_key min_key;
2239 struct btrfs_key max_key;
2240 struct btrfs_root *log = root->log_root;
2241 struct extent_buffer *src;
2245 u64 first_offset = min_offset;
2246 u64 last_offset = (u64)-1;
2248 log = root->log_root;
2249 max_key.objectid = inode->i_ino;
2250 max_key.offset = (u64)-1;
2251 max_key.type = key_type;
2253 min_key.objectid = inode->i_ino;
2254 min_key.type = key_type;
2255 min_key.offset = min_offset;
2257 path->keep_locks = 1;
2259 ret = btrfs_search_forward(root, &min_key, &max_key,
2260 path, 0, trans->transid);
2263 * we didn't find anything from this transaction, see if there
2264 * is anything at all
2266 if (ret != 0 || min_key.objectid != inode->i_ino ||
2267 min_key.type != key_type) {
2268 min_key.objectid = inode->i_ino;
2269 min_key.type = key_type;
2270 min_key.offset = (u64)-1;
2271 btrfs_release_path(root, path);
2272 ret = btrfs_search_slot(NULL, root, &min_key, path, 0, 0);
2274 btrfs_release_path(root, path);
2277 ret = btrfs_previous_item(root, path, inode->i_ino, key_type);
2279 /* if ret == 0 there are items for this type,
2280 * create a range to tell us the last key of this type.
2281 * otherwise, there are no items in this directory after
2282 * *min_offset, and we create a range to indicate that.
2285 struct btrfs_key tmp;
2286 btrfs_item_key_to_cpu(path->nodes[0], &tmp,
2288 if (key_type == tmp.type)
2289 first_offset = max(min_offset, tmp.offset) + 1;
2294 /* go backward to find any previous key */
2295 ret = btrfs_previous_item(root, path, inode->i_ino, key_type);
2297 struct btrfs_key tmp;
2298 btrfs_item_key_to_cpu(path->nodes[0], &tmp, path->slots[0]);
2299 if (key_type == tmp.type) {
2300 first_offset = tmp.offset;
2301 ret = overwrite_item(trans, log, dst_path,
2302 path->nodes[0], path->slots[0],
2306 btrfs_release_path(root, path);
2308 /* find the first key from this transaction again */
2309 ret = btrfs_search_slot(NULL, root, &min_key, path, 0, 0);
2316 * we have a block from this transaction, log every item in it
2317 * from our directory
2320 struct btrfs_key tmp;
2321 src = path->nodes[0];
2322 nritems = btrfs_header_nritems(src);
2323 for (i = path->slots[0]; i < nritems; i++) {
2324 btrfs_item_key_to_cpu(src, &min_key, i);
2326 if (min_key.objectid != inode->i_ino ||
2327 min_key.type != key_type)
2329 ret = overwrite_item(trans, log, dst_path, src, i,
2333 path->slots[0] = nritems;
2336 * look ahead to the next item and see if it is also
2337 * from this directory and from this transaction
2339 ret = btrfs_next_leaf(root, path);
2341 last_offset = (u64)-1;
2344 btrfs_item_key_to_cpu(path->nodes[0], &tmp, path->slots[0]);
2345 if (tmp.objectid != inode->i_ino || tmp.type != key_type) {
2346 last_offset = (u64)-1;
2349 if (btrfs_header_generation(path->nodes[0]) != trans->transid) {
2350 ret = overwrite_item(trans, log, dst_path,
2351 path->nodes[0], path->slots[0],
2355 last_offset = tmp.offset;
2360 *last_offset_ret = last_offset;
2361 btrfs_release_path(root, path);
2362 btrfs_release_path(log, dst_path);
2364 /* insert the log range keys to indicate where the log is valid */
2365 ret = insert_dir_log_key(trans, log, path, key_type, inode->i_ino,
2366 first_offset, last_offset);
2372 * logging directories is very similar to logging inodes, We find all the items
2373 * from the current transaction and write them to the log.
2375 * The recovery code scans the directory in the subvolume, and if it finds a
2376 * key in the range logged that is not present in the log tree, then it means
2377 * that dir entry was unlinked during the transaction.
2379 * In order for that scan to work, we must include one key smaller than
2380 * the smallest logged by this transaction and one key larger than the largest
2381 * key logged by this transaction.
2383 static noinline int log_directory_changes(struct btrfs_trans_handle *trans,
2384 struct btrfs_root *root, struct inode *inode,
2385 struct btrfs_path *path,
2386 struct btrfs_path *dst_path)
2391 int key_type = BTRFS_DIR_ITEM_KEY;
2397 ret = log_dir_items(trans, root, inode, path,
2398 dst_path, key_type, min_key,
2401 if (max_key == (u64)-1)
2403 min_key = max_key + 1;
2406 if (key_type == BTRFS_DIR_ITEM_KEY) {
2407 key_type = BTRFS_DIR_INDEX_KEY;
2414 * a helper function to drop items from the log before we relog an
2415 * inode. max_key_type indicates the highest item type to remove.
2416 * This cannot be run for file data extents because it does not
2417 * free the extents they point to.
2419 static int drop_objectid_items(struct btrfs_trans_handle *trans,
2420 struct btrfs_root *log,
2421 struct btrfs_path *path,
2422 u64 objectid, int max_key_type)
2425 struct btrfs_key key;
2426 struct btrfs_key found_key;
2428 key.objectid = objectid;
2429 key.type = max_key_type;
2430 key.offset = (u64)-1;
2433 ret = btrfs_search_slot(trans, log, &key, path, -1, 1);
2438 if (path->slots[0] == 0)
2442 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
2445 if (found_key.objectid != objectid)
2448 ret = btrfs_del_item(trans, log, path);
2450 btrfs_release_path(log, path);
2452 btrfs_release_path(log, path);
2456 static noinline int copy_extent_csums(struct btrfs_trans_handle *trans,
2457 struct list_head *list,
2458 struct btrfs_root *root,
2459 u64 disk_bytenr, u64 len)
2461 struct btrfs_ordered_sum *sums;
2462 struct btrfs_sector_sum *sector_sum;
2464 struct btrfs_path *path;
2465 struct btrfs_csum_item *item = NULL;
2466 u64 end = disk_bytenr + len;
2467 u64 item_start_offset = 0;
2468 u64 item_last_offset = 0;
2471 u16 csum_size = btrfs_super_csum_size(&root->fs_info->super_copy);
2473 sums = kzalloc(btrfs_ordered_sum_size(root, len), GFP_NOFS);
2475 sector_sum = sums->sums;
2476 sums->bytenr = disk_bytenr;
2478 list_add_tail(&sums->list, list);
2480 path = btrfs_alloc_path();
2481 while (disk_bytenr < end) {
2482 if (!item || disk_bytenr < item_start_offset ||
2483 disk_bytenr >= item_last_offset) {
2484 struct btrfs_key found_key;
2488 btrfs_release_path(root, path);
2489 item = btrfs_lookup_csum(NULL, root, path,
2492 ret = PTR_ERR(item);
2493 if (ret == -ENOENT || ret == -EFBIG)
2496 printk(KERN_INFO "log no csum found for "
2498 (unsigned long long)disk_bytenr);
2500 btrfs_release_path(root, path);
2503 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
2506 item_start_offset = found_key.offset;
2507 item_size = btrfs_item_size_nr(path->nodes[0],
2509 item_last_offset = item_start_offset +
2510 (item_size / csum_size) *
2512 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2513 struct btrfs_csum_item);
2516 * this byte range must be able to fit inside
2517 * a single leaf so it will also fit inside a u32
2519 diff = disk_bytenr - item_start_offset;
2520 diff = diff / root->sectorsize;
2521 diff = diff * csum_size;
2523 read_extent_buffer(path->nodes[0], &sum,
2524 ((unsigned long)item) + diff,
2527 sector_sum->bytenr = disk_bytenr;
2528 sector_sum->sum = sum;
2529 disk_bytenr += root->sectorsize;
2532 btrfs_free_path(path);
2536 static noinline int copy_items(struct btrfs_trans_handle *trans,
2537 struct btrfs_root *log,
2538 struct btrfs_path *dst_path,
2539 struct extent_buffer *src,
2540 int start_slot, int nr, int inode_only)
2542 unsigned long src_offset;
2543 unsigned long dst_offset;
2544 struct btrfs_file_extent_item *extent;
2545 struct btrfs_inode_item *inode_item;
2547 struct btrfs_key *ins_keys;
2551 struct list_head ordered_sums;
2553 INIT_LIST_HEAD(&ordered_sums);
2555 ins_data = kmalloc(nr * sizeof(struct btrfs_key) +
2556 nr * sizeof(u32), GFP_NOFS);
2557 ins_sizes = (u32 *)ins_data;
2558 ins_keys = (struct btrfs_key *)(ins_data + nr * sizeof(u32));
2560 for (i = 0; i < nr; i++) {
2561 ins_sizes[i] = btrfs_item_size_nr(src, i + start_slot);
2562 btrfs_item_key_to_cpu(src, ins_keys + i, i + start_slot);
2564 ret = btrfs_insert_empty_items(trans, log, dst_path,
2565 ins_keys, ins_sizes, nr);
2568 for (i = 0; i < nr; i++) {
2569 dst_offset = btrfs_item_ptr_offset(dst_path->nodes[0],
2570 dst_path->slots[0]);
2572 src_offset = btrfs_item_ptr_offset(src, start_slot + i);
2574 copy_extent_buffer(dst_path->nodes[0], src, dst_offset,
2575 src_offset, ins_sizes[i]);
2577 if (inode_only == LOG_INODE_EXISTS &&
2578 ins_keys[i].type == BTRFS_INODE_ITEM_KEY) {
2579 inode_item = btrfs_item_ptr(dst_path->nodes[0],
2581 struct btrfs_inode_item);
2582 btrfs_set_inode_size(dst_path->nodes[0], inode_item, 0);
2584 /* set the generation to zero so the recover code
2585 * can tell the difference between an logging
2586 * just to say 'this inode exists' and a logging
2587 * to say 'update this inode with these values'
2589 btrfs_set_inode_generation(dst_path->nodes[0],
2592 /* take a reference on file data extents so that truncates
2593 * or deletes of this inode don't have to relog the inode
2596 if (btrfs_key_type(ins_keys + i) == BTRFS_EXTENT_DATA_KEY) {
2598 extent = btrfs_item_ptr(src, start_slot + i,
2599 struct btrfs_file_extent_item);
2601 found_type = btrfs_file_extent_type(src, extent);
2602 if (found_type == BTRFS_FILE_EXTENT_REG ||
2603 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
2604 u64 ds = btrfs_file_extent_disk_bytenr(src,
2606 u64 dl = btrfs_file_extent_disk_num_bytes(src,
2608 u64 cs = btrfs_file_extent_offset(src, extent);
2609 u64 cl = btrfs_file_extent_num_bytes(src,
2611 if (btrfs_file_extent_compression(src,
2616 /* ds == 0 is a hole */
2618 ret = btrfs_inc_extent_ref(trans, log,
2620 dst_path->nodes[0]->start,
2621 BTRFS_TREE_LOG_OBJECTID,
2623 ins_keys[i].objectid);
2625 ret = copy_extent_csums(trans,
2627 log->fs_info->csum_root,
2633 dst_path->slots[0]++;
2636 btrfs_mark_buffer_dirty(dst_path->nodes[0]);
2637 btrfs_release_path(log, dst_path);
2641 * we have to do this after the loop above to avoid changing the
2642 * log tree while trying to change the log tree.
2644 while (!list_empty(&ordered_sums)) {
2645 struct btrfs_ordered_sum *sums = list_entry(ordered_sums.next,
2646 struct btrfs_ordered_sum,
2648 ret = btrfs_csum_file_blocks(trans, log, sums);
2650 list_del(&sums->list);
2656 /* log a single inode in the tree log.
2657 * At least one parent directory for this inode must exist in the tree
2658 * or be logged already.
2660 * Any items from this inode changed by the current transaction are copied
2661 * to the log tree. An extra reference is taken on any extents in this
2662 * file, allowing us to avoid a whole pile of corner cases around logging
2663 * blocks that have been removed from the tree.
2665 * See LOG_INODE_ALL and related defines for a description of what inode_only
2668 * This handles both files and directories.
2670 static int __btrfs_log_inode(struct btrfs_trans_handle *trans,
2671 struct btrfs_root *root, struct inode *inode,
2674 struct btrfs_path *path;
2675 struct btrfs_path *dst_path;
2676 struct btrfs_key min_key;
2677 struct btrfs_key max_key;
2678 struct btrfs_root *log = root->log_root;
2679 struct extent_buffer *src = NULL;
2683 int ins_start_slot = 0;
2686 log = root->log_root;
2688 path = btrfs_alloc_path();
2689 dst_path = btrfs_alloc_path();
2691 min_key.objectid = inode->i_ino;
2692 min_key.type = BTRFS_INODE_ITEM_KEY;
2695 max_key.objectid = inode->i_ino;
2696 if (inode_only == LOG_INODE_EXISTS || S_ISDIR(inode->i_mode))
2697 max_key.type = BTRFS_XATTR_ITEM_KEY;
2699 max_key.type = (u8)-1;
2700 max_key.offset = (u64)-1;
2703 * if this inode has already been logged and we're in inode_only
2704 * mode, we don't want to delete the things that have already
2705 * been written to the log.
2707 * But, if the inode has been through an inode_only log,
2708 * the logged_trans field is not set. This allows us to catch
2709 * any new names for this inode in the backrefs by logging it
2712 if (inode_only == LOG_INODE_EXISTS &&
2713 BTRFS_I(inode)->logged_trans == trans->transid) {
2714 btrfs_free_path(path);
2715 btrfs_free_path(dst_path);
2718 mutex_lock(&BTRFS_I(inode)->log_mutex);
2721 * a brute force approach to making sure we get the most uptodate
2722 * copies of everything.
2724 if (S_ISDIR(inode->i_mode)) {
2725 int max_key_type = BTRFS_DIR_LOG_INDEX_KEY;
2727 if (inode_only == LOG_INODE_EXISTS)
2728 max_key_type = BTRFS_XATTR_ITEM_KEY;
2729 ret = drop_objectid_items(trans, log, path,
2730 inode->i_ino, max_key_type);
2732 ret = btrfs_truncate_inode_items(trans, log, inode, 0, 0);
2735 path->keep_locks = 1;
2739 ret = btrfs_search_forward(root, &min_key, &max_key,
2740 path, 0, trans->transid);
2744 /* note, ins_nr might be > 0 here, cleanup outside the loop */
2745 if (min_key.objectid != inode->i_ino)
2747 if (min_key.type > max_key.type)
2750 src = path->nodes[0];
2751 size = btrfs_item_size_nr(src, path->slots[0]);
2752 if (ins_nr && ins_start_slot + ins_nr == path->slots[0]) {
2755 } else if (!ins_nr) {
2756 ins_start_slot = path->slots[0];
2761 ret = copy_items(trans, log, dst_path, src, ins_start_slot,
2762 ins_nr, inode_only);
2765 ins_start_slot = path->slots[0];
2768 nritems = btrfs_header_nritems(path->nodes[0]);
2770 if (path->slots[0] < nritems) {
2771 btrfs_item_key_to_cpu(path->nodes[0], &min_key,
2776 ret = copy_items(trans, log, dst_path, src,
2778 ins_nr, inode_only);
2782 btrfs_release_path(root, path);
2784 if (min_key.offset < (u64)-1)
2786 else if (min_key.type < (u8)-1)
2788 else if (min_key.objectid < (u64)-1)
2794 ret = copy_items(trans, log, dst_path, src,
2796 ins_nr, inode_only);
2801 if (inode_only == LOG_INODE_ALL && S_ISDIR(inode->i_mode)) {
2802 btrfs_release_path(root, path);
2803 btrfs_release_path(log, dst_path);
2804 BTRFS_I(inode)->log_dirty_trans = 0;
2805 ret = log_directory_changes(trans, root, inode, path, dst_path);
2808 BTRFS_I(inode)->logged_trans = trans->transid;
2809 mutex_unlock(&BTRFS_I(inode)->log_mutex);
2811 btrfs_free_path(path);
2812 btrfs_free_path(dst_path);
2814 mutex_lock(&root->fs_info->tree_log_mutex);
2815 ret = update_log_root(trans, log);
2817 mutex_unlock(&root->fs_info->tree_log_mutex);
2822 int btrfs_log_inode(struct btrfs_trans_handle *trans,
2823 struct btrfs_root *root, struct inode *inode,
2828 start_log_trans(trans, root);
2829 ret = __btrfs_log_inode(trans, root, inode, inode_only);
2830 end_log_trans(root);
2835 * helper function around btrfs_log_inode to make sure newly created
2836 * parent directories also end up in the log. A minimal inode and backref
2837 * only logging is done of any parent directories that are older than
2838 * the last committed transaction
2840 int btrfs_log_dentry(struct btrfs_trans_handle *trans,
2841 struct btrfs_root *root, struct dentry *dentry)
2843 int inode_only = LOG_INODE_ALL;
2844 struct super_block *sb;
2847 start_log_trans(trans, root);
2848 sb = dentry->d_inode->i_sb;
2850 ret = __btrfs_log_inode(trans, root, dentry->d_inode,
2853 inode_only = LOG_INODE_EXISTS;
2855 dentry = dentry->d_parent;
2856 if (!dentry || !dentry->d_inode || sb != dentry->d_inode->i_sb)
2859 if (BTRFS_I(dentry->d_inode)->generation <=
2860 root->fs_info->last_trans_committed)
2863 end_log_trans(root);
2868 * it is not safe to log dentry if the chunk root has added new
2869 * chunks. This returns 0 if the dentry was logged, and 1 otherwise.
2870 * If this returns 1, you must commit the transaction to safely get your
2873 int btrfs_log_dentry_safe(struct btrfs_trans_handle *trans,
2874 struct btrfs_root *root, struct dentry *dentry)
2877 gen = root->fs_info->last_trans_new_blockgroup;
2878 if (gen > root->fs_info->last_trans_committed)
2881 return btrfs_log_dentry(trans, root, dentry);
2885 * should be called during mount to recover any replay any log trees
2888 int btrfs_recover_log_trees(struct btrfs_root *log_root_tree)
2891 struct btrfs_path *path;
2892 struct btrfs_trans_handle *trans;
2893 struct btrfs_key key;
2894 struct btrfs_key found_key;
2895 struct btrfs_key tmp_key;
2896 struct btrfs_root *log;
2897 struct btrfs_fs_info *fs_info = log_root_tree->fs_info;
2899 struct walk_control wc = {
2900 .process_func = process_one_buffer,
2904 fs_info->log_root_recovering = 1;
2905 path = btrfs_alloc_path();
2908 trans = btrfs_start_transaction(fs_info->tree_root, 1);
2913 walk_log_tree(trans, log_root_tree, &wc);
2916 key.objectid = BTRFS_TREE_LOG_OBJECTID;
2917 key.offset = (u64)-1;
2918 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
2921 ret = btrfs_search_slot(NULL, log_root_tree, &key, path, 0, 0);
2925 if (path->slots[0] == 0)
2929 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
2931 btrfs_release_path(log_root_tree, path);
2932 if (found_key.objectid != BTRFS_TREE_LOG_OBJECTID)
2935 log = btrfs_read_fs_root_no_radix(log_root_tree,
2940 tmp_key.objectid = found_key.offset;
2941 tmp_key.type = BTRFS_ROOT_ITEM_KEY;
2942 tmp_key.offset = (u64)-1;
2944 wc.replay_dest = btrfs_read_fs_root_no_name(fs_info, &tmp_key);
2946 BUG_ON(!wc.replay_dest);
2948 btrfs_record_root_in_trans(wc.replay_dest);
2949 ret = walk_log_tree(trans, log, &wc);
2952 if (wc.stage == LOG_WALK_REPLAY_ALL) {
2953 ret = fixup_inode_link_counts(trans, wc.replay_dest,
2957 ret = btrfs_find_highest_inode(wc.replay_dest, &highest_inode);
2959 wc.replay_dest->highest_inode = highest_inode;
2960 wc.replay_dest->last_inode_alloc = highest_inode;
2963 key.offset = found_key.offset - 1;
2964 free_extent_buffer(log->node);
2967 if (found_key.offset == 0)
2970 btrfs_release_path(log_root_tree, path);
2972 /* step one is to pin it all, step two is to replay just inodes */
2975 wc.process_func = replay_one_buffer;
2976 wc.stage = LOG_WALK_REPLAY_INODES;
2979 /* step three is to replay everything */
2980 if (wc.stage < LOG_WALK_REPLAY_ALL) {
2985 btrfs_free_path(path);
2987 free_extent_buffer(log_root_tree->node);
2988 log_root_tree->log_root = NULL;
2989 fs_info->log_root_recovering = 0;
2991 /* step 4: commit the transaction, which also unpins the blocks */
2992 btrfs_commit_transaction(trans, fs_info->tree_root);
2994 kfree(log_root_tree);