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>
20 #include <linux/slab.h>
22 #include "transaction.h"
25 #include "print-tree.h"
29 /* magic values for the inode_only field in btrfs_log_inode:
31 * LOG_INODE_ALL means to log everything
32 * LOG_INODE_EXISTS means to log just enough to recreate the inode
35 #define LOG_INODE_ALL 0
36 #define LOG_INODE_EXISTS 1
39 * directory trouble cases
41 * 1) on rename or unlink, if the inode being unlinked isn't in the fsync
42 * log, we must force a full commit before doing an fsync of the directory
43 * where the unlink was done.
44 * ---> record transid of last unlink/rename per directory
48 * rename foo/some_dir foo2/some_dir
50 * fsync foo/some_dir/some_file
52 * The fsync above will unlink the original some_dir without recording
53 * it in its new location (foo2). After a crash, some_dir will be gone
54 * unless the fsync of some_file forces a full commit
56 * 2) we must log any new names for any file or dir that is in the fsync
57 * log. ---> check inode while renaming/linking.
59 * 2a) we must log any new names for any file or dir during rename
60 * when the directory they are being removed from was logged.
61 * ---> check inode and old parent dir during rename
63 * 2a is actually the more important variant. With the extra logging
64 * a crash might unlink the old name without recreating the new one
66 * 3) after a crash, we must go through any directories with a link count
67 * of zero and redo the rm -rf
74 * The directory f1 was fully removed from the FS, but fsync was never
75 * called on f1, only its parent dir. After a crash the rm -rf must
76 * be replayed. This must be able to recurse down the entire
77 * directory tree. The inode link count fixup code takes care of the
82 * stages for the tree walking. The first
83 * stage (0) is to only pin down the blocks we find
84 * the second stage (1) is to make sure that all the inodes
85 * we find in the log are created in the subvolume.
87 * The last stage is to deal with directories and links and extents
88 * and all the other fun semantics
90 #define LOG_WALK_PIN_ONLY 0
91 #define LOG_WALK_REPLAY_INODES 1
92 #define LOG_WALK_REPLAY_ALL 2
94 static int btrfs_log_inode(struct btrfs_trans_handle *trans,
95 struct btrfs_root *root, struct inode *inode,
97 static int link_to_fixup_dir(struct btrfs_trans_handle *trans,
98 struct btrfs_root *root,
99 struct btrfs_path *path, u64 objectid);
100 static noinline int replay_dir_deletes(struct btrfs_trans_handle *trans,
101 struct btrfs_root *root,
102 struct btrfs_root *log,
103 struct btrfs_path *path,
104 u64 dirid, int del_all);
107 * tree logging is a special write ahead log used to make sure that
108 * fsyncs and O_SYNCs can happen without doing full tree commits.
110 * Full tree commits are expensive because they require commonly
111 * modified blocks to be recowed, creating many dirty pages in the
112 * extent tree an 4x-6x higher write load than ext3.
114 * Instead of doing a tree commit on every fsync, we use the
115 * key ranges and transaction ids to find items for a given file or directory
116 * that have changed in this transaction. Those items are copied into
117 * a special tree (one per subvolume root), that tree is written to disk
118 * and then the fsync is considered complete.
120 * After a crash, items are copied out of the log-tree back into the
121 * subvolume tree. Any file data extents found are recorded in the extent
122 * allocation tree, and the log-tree freed.
124 * The log tree is read three times, once to pin down all the extents it is
125 * using in ram and once, once to create all the inodes logged in the tree
126 * and once to do all the other items.
130 * start a sub transaction and setup the log tree
131 * this increments the log tree writer count to make the people
132 * syncing the tree wait for us to finish
134 static int start_log_trans(struct btrfs_trans_handle *trans,
135 struct btrfs_root *root)
140 mutex_lock(&root->log_mutex);
141 if (root->log_root) {
142 if (!root->log_start_pid) {
143 root->log_start_pid = current->pid;
144 root->log_multiple_pids = false;
145 } else if (root->log_start_pid != current->pid) {
146 root->log_multiple_pids = true;
150 atomic_inc(&root->log_writers);
151 mutex_unlock(&root->log_mutex);
154 root->log_multiple_pids = false;
155 root->log_start_pid = current->pid;
156 mutex_lock(&root->fs_info->tree_log_mutex);
157 if (!root->fs_info->log_root_tree) {
158 ret = btrfs_init_log_root_tree(trans, root->fs_info);
162 if (err == 0 && !root->log_root) {
163 ret = btrfs_add_log_tree(trans, root);
167 mutex_unlock(&root->fs_info->tree_log_mutex);
169 atomic_inc(&root->log_writers);
170 mutex_unlock(&root->log_mutex);
175 * returns 0 if there was a log transaction running and we were able
176 * to join, or returns -ENOENT if there were not transactions
179 static int join_running_log_trans(struct btrfs_root *root)
187 mutex_lock(&root->log_mutex);
188 if (root->log_root) {
190 atomic_inc(&root->log_writers);
192 mutex_unlock(&root->log_mutex);
197 * This either makes the current running log transaction wait
198 * until you call btrfs_end_log_trans() or it makes any future
199 * log transactions wait until you call btrfs_end_log_trans()
201 int btrfs_pin_log_trans(struct btrfs_root *root)
205 mutex_lock(&root->log_mutex);
206 atomic_inc(&root->log_writers);
207 mutex_unlock(&root->log_mutex);
212 * indicate we're done making changes to the log tree
213 * and wake up anyone waiting to do a sync
215 void btrfs_end_log_trans(struct btrfs_root *root)
217 if (atomic_dec_and_test(&root->log_writers)) {
219 if (waitqueue_active(&root->log_writer_wait))
220 wake_up(&root->log_writer_wait);
226 * the walk control struct is used to pass state down the chain when
227 * processing the log tree. The stage field tells us which part
228 * of the log tree processing we are currently doing. The others
229 * are state fields used for that specific part
231 struct walk_control {
232 /* should we free the extent on disk when done? This is used
233 * at transaction commit time while freeing a log tree
237 /* should we write out the extent buffer? This is used
238 * while flushing the log tree to disk during a sync
242 /* should we wait for the extent buffer io to finish? Also used
243 * while flushing the log tree to disk for a sync
247 /* pin only walk, we record which extents on disk belong to the
252 /* what stage of the replay code we're currently in */
255 /* the root we are currently replaying */
256 struct btrfs_root *replay_dest;
258 /* the trans handle for the current replay */
259 struct btrfs_trans_handle *trans;
261 /* the function that gets used to process blocks we find in the
262 * tree. Note the extent_buffer might not be up to date when it is
263 * passed in, and it must be checked or read if you need the data
266 int (*process_func)(struct btrfs_root *log, struct extent_buffer *eb,
267 struct walk_control *wc, u64 gen);
271 * process_func used to pin down extents, write them or wait on them
273 static int process_one_buffer(struct btrfs_root *log,
274 struct extent_buffer *eb,
275 struct walk_control *wc, u64 gen)
278 btrfs_pin_extent_for_log_replay(wc->trans,
279 log->fs_info->extent_root,
282 if (btrfs_buffer_uptodate(eb, gen, 0)) {
284 btrfs_write_tree_block(eb);
286 btrfs_wait_tree_block_writeback(eb);
292 * Item overwrite used by replay and tree logging. eb, slot and key all refer
293 * to the src data we are copying out.
295 * root is the tree we are copying into, and path is a scratch
296 * path for use in this function (it should be released on entry and
297 * will be released on exit).
299 * If the key is already in the destination tree the existing item is
300 * overwritten. If the existing item isn't big enough, it is extended.
301 * If it is too large, it is truncated.
303 * If the key isn't in the destination yet, a new item is inserted.
305 static noinline int overwrite_item(struct btrfs_trans_handle *trans,
306 struct btrfs_root *root,
307 struct btrfs_path *path,
308 struct extent_buffer *eb, int slot,
309 struct btrfs_key *key)
313 u64 saved_i_size = 0;
314 int save_old_i_size = 0;
315 unsigned long src_ptr;
316 unsigned long dst_ptr;
317 int overwrite_root = 0;
319 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID)
322 item_size = btrfs_item_size_nr(eb, slot);
323 src_ptr = btrfs_item_ptr_offset(eb, slot);
325 /* look for the key in the destination tree */
326 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
330 u32 dst_size = btrfs_item_size_nr(path->nodes[0],
332 if (dst_size != item_size)
335 if (item_size == 0) {
336 btrfs_release_path(path);
339 dst_copy = kmalloc(item_size, GFP_NOFS);
340 src_copy = kmalloc(item_size, GFP_NOFS);
341 if (!dst_copy || !src_copy) {
342 btrfs_release_path(path);
348 read_extent_buffer(eb, src_copy, src_ptr, item_size);
350 dst_ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
351 read_extent_buffer(path->nodes[0], dst_copy, dst_ptr,
353 ret = memcmp(dst_copy, src_copy, item_size);
358 * they have the same contents, just return, this saves
359 * us from cowing blocks in the destination tree and doing
360 * extra writes that may not have been done by a previous
364 btrfs_release_path(path);
370 btrfs_release_path(path);
371 /* try to insert the key into the destination tree */
372 ret = btrfs_insert_empty_item(trans, root, path,
375 /* make sure any existing item is the correct size */
376 if (ret == -EEXIST) {
378 found_size = btrfs_item_size_nr(path->nodes[0],
380 if (found_size > item_size)
381 btrfs_truncate_item(trans, root, path, item_size, 1);
382 else if (found_size < item_size)
383 btrfs_extend_item(trans, root, path,
384 item_size - found_size);
388 dst_ptr = btrfs_item_ptr_offset(path->nodes[0],
391 /* don't overwrite an existing inode if the generation number
392 * was logged as zero. This is done when the tree logging code
393 * is just logging an inode to make sure it exists after recovery.
395 * Also, don't overwrite i_size on directories during replay.
396 * log replay inserts and removes directory items based on the
397 * state of the tree found in the subvolume, and i_size is modified
400 if (key->type == BTRFS_INODE_ITEM_KEY && ret == -EEXIST) {
401 struct btrfs_inode_item *src_item;
402 struct btrfs_inode_item *dst_item;
404 src_item = (struct btrfs_inode_item *)src_ptr;
405 dst_item = (struct btrfs_inode_item *)dst_ptr;
407 if (btrfs_inode_generation(eb, src_item) == 0)
410 if (overwrite_root &&
411 S_ISDIR(btrfs_inode_mode(eb, src_item)) &&
412 S_ISDIR(btrfs_inode_mode(path->nodes[0], dst_item))) {
414 saved_i_size = btrfs_inode_size(path->nodes[0],
419 copy_extent_buffer(path->nodes[0], eb, dst_ptr,
422 if (save_old_i_size) {
423 struct btrfs_inode_item *dst_item;
424 dst_item = (struct btrfs_inode_item *)dst_ptr;
425 btrfs_set_inode_size(path->nodes[0], dst_item, saved_i_size);
428 /* make sure the generation is filled in */
429 if (key->type == BTRFS_INODE_ITEM_KEY) {
430 struct btrfs_inode_item *dst_item;
431 dst_item = (struct btrfs_inode_item *)dst_ptr;
432 if (btrfs_inode_generation(path->nodes[0], dst_item) == 0) {
433 btrfs_set_inode_generation(path->nodes[0], dst_item,
438 btrfs_mark_buffer_dirty(path->nodes[0]);
439 btrfs_release_path(path);
444 * simple helper to read an inode off the disk from a given root
445 * This can only be called for subvolume roots and not for the log
447 static noinline struct inode *read_one_inode(struct btrfs_root *root,
450 struct btrfs_key key;
453 key.objectid = objectid;
454 key.type = BTRFS_INODE_ITEM_KEY;
456 inode = btrfs_iget(root->fs_info->sb, &key, root, NULL);
459 } else if (is_bad_inode(inode)) {
466 /* replays a single extent in 'eb' at 'slot' with 'key' into the
467 * subvolume 'root'. path is released on entry and should be released
470 * extents in the log tree have not been allocated out of the extent
471 * tree yet. So, this completes the allocation, taking a reference
472 * as required if the extent already exists or creating a new extent
473 * if it isn't in the extent allocation tree yet.
475 * The extent is inserted into the file, dropping any existing extents
476 * from the file that overlap the new one.
478 static noinline int replay_one_extent(struct btrfs_trans_handle *trans,
479 struct btrfs_root *root,
480 struct btrfs_path *path,
481 struct extent_buffer *eb, int slot,
482 struct btrfs_key *key)
485 u64 mask = root->sectorsize - 1;
488 u64 start = key->offset;
490 struct btrfs_file_extent_item *item;
491 struct inode *inode = NULL;
495 item = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
496 found_type = btrfs_file_extent_type(eb, item);
498 if (found_type == BTRFS_FILE_EXTENT_REG ||
499 found_type == BTRFS_FILE_EXTENT_PREALLOC)
500 extent_end = start + btrfs_file_extent_num_bytes(eb, item);
501 else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
502 size = btrfs_file_extent_inline_len(eb, item);
503 extent_end = (start + size + mask) & ~mask;
509 inode = read_one_inode(root, key->objectid);
516 * first check to see if we already have this extent in the
517 * file. This must be done before the btrfs_drop_extents run
518 * so we don't try to drop this extent.
520 ret = btrfs_lookup_file_extent(trans, root, path, btrfs_ino(inode),
524 (found_type == BTRFS_FILE_EXTENT_REG ||
525 found_type == BTRFS_FILE_EXTENT_PREALLOC)) {
526 struct btrfs_file_extent_item cmp1;
527 struct btrfs_file_extent_item cmp2;
528 struct btrfs_file_extent_item *existing;
529 struct extent_buffer *leaf;
531 leaf = path->nodes[0];
532 existing = btrfs_item_ptr(leaf, path->slots[0],
533 struct btrfs_file_extent_item);
535 read_extent_buffer(eb, &cmp1, (unsigned long)item,
537 read_extent_buffer(leaf, &cmp2, (unsigned long)existing,
541 * we already have a pointer to this exact extent,
542 * we don't have to do anything
544 if (memcmp(&cmp1, &cmp2, sizeof(cmp1)) == 0) {
545 btrfs_release_path(path);
549 btrfs_release_path(path);
551 saved_nbytes = inode_get_bytes(inode);
552 /* drop any overlapping extents */
553 ret = btrfs_drop_extents(trans, inode, start, extent_end,
557 if (found_type == BTRFS_FILE_EXTENT_REG ||
558 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
560 unsigned long dest_offset;
561 struct btrfs_key ins;
563 ret = btrfs_insert_empty_item(trans, root, path, key,
566 dest_offset = btrfs_item_ptr_offset(path->nodes[0],
568 copy_extent_buffer(path->nodes[0], eb, dest_offset,
569 (unsigned long)item, sizeof(*item));
571 ins.objectid = btrfs_file_extent_disk_bytenr(eb, item);
572 ins.offset = btrfs_file_extent_disk_num_bytes(eb, item);
573 ins.type = BTRFS_EXTENT_ITEM_KEY;
574 offset = key->offset - btrfs_file_extent_offset(eb, item);
576 if (ins.objectid > 0) {
579 LIST_HEAD(ordered_sums);
581 * is this extent already allocated in the extent
582 * allocation tree? If so, just add a reference
584 ret = btrfs_lookup_extent(root, ins.objectid,
587 ret = btrfs_inc_extent_ref(trans, root,
588 ins.objectid, ins.offset,
589 0, root->root_key.objectid,
590 key->objectid, offset, 0);
594 * insert the extent pointer in the extent
597 ret = btrfs_alloc_logged_file_extent(trans,
598 root, root->root_key.objectid,
599 key->objectid, offset, &ins);
602 btrfs_release_path(path);
604 if (btrfs_file_extent_compression(eb, item)) {
605 csum_start = ins.objectid;
606 csum_end = csum_start + ins.offset;
608 csum_start = ins.objectid +
609 btrfs_file_extent_offset(eb, item);
610 csum_end = csum_start +
611 btrfs_file_extent_num_bytes(eb, item);
614 ret = btrfs_lookup_csums_range(root->log_root,
615 csum_start, csum_end - 1,
618 while (!list_empty(&ordered_sums)) {
619 struct btrfs_ordered_sum *sums;
620 sums = list_entry(ordered_sums.next,
621 struct btrfs_ordered_sum,
623 ret = btrfs_csum_file_blocks(trans,
624 root->fs_info->csum_root,
627 list_del(&sums->list);
631 btrfs_release_path(path);
633 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
634 /* inline extents are easy, we just overwrite them */
635 ret = overwrite_item(trans, root, path, eb, slot, key);
639 inode_set_bytes(inode, saved_nbytes);
640 btrfs_update_inode(trans, root, inode);
648 * when cleaning up conflicts between the directory names in the
649 * subvolume, directory names in the log and directory names in the
650 * inode back references, we may have to unlink inodes from directories.
652 * This is a helper function to do the unlink of a specific directory
655 static noinline int drop_one_dir_item(struct btrfs_trans_handle *trans,
656 struct btrfs_root *root,
657 struct btrfs_path *path,
659 struct btrfs_dir_item *di)
664 struct extent_buffer *leaf;
665 struct btrfs_key location;
668 leaf = path->nodes[0];
670 btrfs_dir_item_key_to_cpu(leaf, di, &location);
671 name_len = btrfs_dir_name_len(leaf, di);
672 name = kmalloc(name_len, GFP_NOFS);
676 read_extent_buffer(leaf, name, (unsigned long)(di + 1), name_len);
677 btrfs_release_path(path);
679 inode = read_one_inode(root, location.objectid);
685 ret = link_to_fixup_dir(trans, root, path, location.objectid);
688 ret = btrfs_unlink_inode(trans, root, dir, inode, name, name_len);
697 * helper function to see if a given name and sequence number found
698 * in an inode back reference are already in a directory and correctly
699 * point to this inode
701 static noinline int inode_in_dir(struct btrfs_root *root,
702 struct btrfs_path *path,
703 u64 dirid, u64 objectid, u64 index,
704 const char *name, int name_len)
706 struct btrfs_dir_item *di;
707 struct btrfs_key location;
710 di = btrfs_lookup_dir_index_item(NULL, root, path, dirid,
711 index, name, name_len, 0);
712 if (di && !IS_ERR(di)) {
713 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location);
714 if (location.objectid != objectid)
718 btrfs_release_path(path);
720 di = btrfs_lookup_dir_item(NULL, root, path, dirid, name, name_len, 0);
721 if (di && !IS_ERR(di)) {
722 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location);
723 if (location.objectid != objectid)
729 btrfs_release_path(path);
734 * helper function to check a log tree for a named back reference in
735 * an inode. This is used to decide if a back reference that is
736 * found in the subvolume conflicts with what we find in the log.
738 * inode backreferences may have multiple refs in a single item,
739 * during replay we process one reference at a time, and we don't
740 * want to delete valid links to a file from the subvolume if that
741 * link is also in the log.
743 static noinline int backref_in_log(struct btrfs_root *log,
744 struct btrfs_key *key,
745 char *name, int namelen)
747 struct btrfs_path *path;
748 struct btrfs_inode_ref *ref;
750 unsigned long ptr_end;
751 unsigned long name_ptr;
757 path = btrfs_alloc_path();
761 ret = btrfs_search_slot(NULL, log, key, path, 0, 0);
765 item_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]);
766 ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
767 ptr_end = ptr + item_size;
768 while (ptr < ptr_end) {
769 ref = (struct btrfs_inode_ref *)ptr;
770 found_name_len = btrfs_inode_ref_name_len(path->nodes[0], ref);
771 if (found_name_len == namelen) {
772 name_ptr = (unsigned long)(ref + 1);
773 ret = memcmp_extent_buffer(path->nodes[0], name,
780 ptr = (unsigned long)(ref + 1) + found_name_len;
783 btrfs_free_path(path);
789 * replay one inode back reference item found in the log tree.
790 * eb, slot and key refer to the buffer and key found in the log tree.
791 * root is the destination we are replaying into, and path is for temp
792 * use by this function. (it should be released on return).
794 static noinline int add_inode_ref(struct btrfs_trans_handle *trans,
795 struct btrfs_root *root,
796 struct btrfs_root *log,
797 struct btrfs_path *path,
798 struct extent_buffer *eb, int slot,
799 struct btrfs_key *key)
801 struct btrfs_inode_ref *ref;
802 struct btrfs_dir_item *di;
805 unsigned long ref_ptr;
806 unsigned long ref_end;
813 * it is possible that we didn't log all the parent directories
814 * for a given inode. If we don't find the dir, just don't
815 * copy the back ref in. The link count fixup code will take
818 dir = read_one_inode(root, key->offset);
822 inode = read_one_inode(root, key->objectid);
828 ref_ptr = btrfs_item_ptr_offset(eb, slot);
829 ref_end = ref_ptr + btrfs_item_size_nr(eb, slot);
832 ref = (struct btrfs_inode_ref *)ref_ptr;
834 namelen = btrfs_inode_ref_name_len(eb, ref);
835 name = kmalloc(namelen, GFP_NOFS);
838 read_extent_buffer(eb, name, (unsigned long)(ref + 1), namelen);
840 /* if we already have a perfect match, we're done */
841 if (inode_in_dir(root, path, btrfs_ino(dir), btrfs_ino(inode),
842 btrfs_inode_ref_index(eb, ref),
848 * look for a conflicting back reference in the metadata.
849 * if we find one we have to unlink that name of the file
850 * before we add our new link. Later on, we overwrite any
851 * existing back reference, and we don't want to create
852 * dangling pointers in the directory.
858 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
862 struct btrfs_inode_ref *victim_ref;
864 unsigned long ptr_end;
865 struct extent_buffer *leaf = path->nodes[0];
867 /* are we trying to overwrite a back ref for the root directory
868 * if so, just jump out, we're done
870 if (key->objectid == key->offset)
873 /* check all the names in this back reference to see
874 * if they are in the log. if so, we allow them to stay
875 * otherwise they must be unlinked as a conflict
877 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
878 ptr_end = ptr + btrfs_item_size_nr(leaf, path->slots[0]);
879 while (ptr < ptr_end) {
880 victim_ref = (struct btrfs_inode_ref *)ptr;
881 victim_name_len = btrfs_inode_ref_name_len(leaf,
883 victim_name = kmalloc(victim_name_len, GFP_NOFS);
884 BUG_ON(!victim_name);
886 read_extent_buffer(leaf, victim_name,
887 (unsigned long)(victim_ref + 1),
890 if (!backref_in_log(log, key, victim_name,
892 btrfs_inc_nlink(inode);
893 btrfs_release_path(path);
895 ret = btrfs_unlink_inode(trans, root, dir,
900 ptr = (unsigned long)(victim_ref + 1) + victim_name_len;
905 * NOTE: we have searched root tree and checked the
906 * coresponding ref, it does not need to check again.
910 btrfs_release_path(path);
912 /* look for a conflicting sequence number */
913 di = btrfs_lookup_dir_index_item(trans, root, path, btrfs_ino(dir),
914 btrfs_inode_ref_index(eb, ref),
916 if (di && !IS_ERR(di)) {
917 ret = drop_one_dir_item(trans, root, path, dir, di);
920 btrfs_release_path(path);
922 /* look for a conflicing name */
923 di = btrfs_lookup_dir_item(trans, root, path, btrfs_ino(dir),
925 if (di && !IS_ERR(di)) {
926 ret = drop_one_dir_item(trans, root, path, dir, di);
929 btrfs_release_path(path);
932 /* insert our name */
933 ret = btrfs_add_link(trans, dir, inode, name, namelen, 0,
934 btrfs_inode_ref_index(eb, ref));
937 btrfs_update_inode(trans, root, inode);
940 ref_ptr = (unsigned long)(ref + 1) + namelen;
942 if (ref_ptr < ref_end)
945 /* finally write the back reference in the inode */
946 ret = overwrite_item(trans, root, path, eb, slot, key);
950 btrfs_release_path(path);
956 static int insert_orphan_item(struct btrfs_trans_handle *trans,
957 struct btrfs_root *root, u64 offset)
960 ret = btrfs_find_orphan_item(root, offset);
962 ret = btrfs_insert_orphan_item(trans, root, offset);
968 * There are a few corners where the link count of the file can't
969 * be properly maintained during replay. So, instead of adding
970 * lots of complexity to the log code, we just scan the backrefs
971 * for any file that has been through replay.
973 * The scan will update the link count on the inode to reflect the
974 * number of back refs found. If it goes down to zero, the iput
975 * will free the inode.
977 static noinline int fixup_inode_link_count(struct btrfs_trans_handle *trans,
978 struct btrfs_root *root,
981 struct btrfs_path *path;
983 struct btrfs_key key;
986 unsigned long ptr_end;
988 u64 ino = btrfs_ino(inode);
991 key.type = BTRFS_INODE_REF_KEY;
992 key.offset = (u64)-1;
994 path = btrfs_alloc_path();
999 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1003 if (path->slots[0] == 0)
1007 btrfs_item_key_to_cpu(path->nodes[0], &key,
1009 if (key.objectid != ino ||
1010 key.type != BTRFS_INODE_REF_KEY)
1012 ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
1013 ptr_end = ptr + btrfs_item_size_nr(path->nodes[0],
1015 while (ptr < ptr_end) {
1016 struct btrfs_inode_ref *ref;
1018 ref = (struct btrfs_inode_ref *)ptr;
1019 name_len = btrfs_inode_ref_name_len(path->nodes[0],
1021 ptr = (unsigned long)(ref + 1) + name_len;
1025 if (key.offset == 0)
1028 btrfs_release_path(path);
1030 btrfs_release_path(path);
1031 if (nlink != inode->i_nlink) {
1032 set_nlink(inode, nlink);
1033 btrfs_update_inode(trans, root, inode);
1035 BTRFS_I(inode)->index_cnt = (u64)-1;
1037 if (inode->i_nlink == 0) {
1038 if (S_ISDIR(inode->i_mode)) {
1039 ret = replay_dir_deletes(trans, root, NULL, path,
1043 ret = insert_orphan_item(trans, root, ino);
1046 btrfs_free_path(path);
1051 static noinline int fixup_inode_link_counts(struct btrfs_trans_handle *trans,
1052 struct btrfs_root *root,
1053 struct btrfs_path *path)
1056 struct btrfs_key key;
1057 struct inode *inode;
1059 key.objectid = BTRFS_TREE_LOG_FIXUP_OBJECTID;
1060 key.type = BTRFS_ORPHAN_ITEM_KEY;
1061 key.offset = (u64)-1;
1063 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1068 if (path->slots[0] == 0)
1073 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1074 if (key.objectid != BTRFS_TREE_LOG_FIXUP_OBJECTID ||
1075 key.type != BTRFS_ORPHAN_ITEM_KEY)
1078 ret = btrfs_del_item(trans, root, path);
1082 btrfs_release_path(path);
1083 inode = read_one_inode(root, key.offset);
1087 ret = fixup_inode_link_count(trans, root, inode);
1093 * fixup on a directory may create new entries,
1094 * make sure we always look for the highset possible
1097 key.offset = (u64)-1;
1101 btrfs_release_path(path);
1107 * record a given inode in the fixup dir so we can check its link
1108 * count when replay is done. The link count is incremented here
1109 * so the inode won't go away until we check it
1111 static noinline int link_to_fixup_dir(struct btrfs_trans_handle *trans,
1112 struct btrfs_root *root,
1113 struct btrfs_path *path,
1116 struct btrfs_key key;
1118 struct inode *inode;
1120 inode = read_one_inode(root, objectid);
1124 key.objectid = BTRFS_TREE_LOG_FIXUP_OBJECTID;
1125 btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
1126 key.offset = objectid;
1128 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1130 btrfs_release_path(path);
1132 btrfs_inc_nlink(inode);
1133 btrfs_update_inode(trans, root, inode);
1134 } else if (ret == -EEXIST) {
1145 * when replaying the log for a directory, we only insert names
1146 * for inodes that actually exist. This means an fsync on a directory
1147 * does not implicitly fsync all the new files in it
1149 static noinline int insert_one_name(struct btrfs_trans_handle *trans,
1150 struct btrfs_root *root,
1151 struct btrfs_path *path,
1152 u64 dirid, u64 index,
1153 char *name, int name_len, u8 type,
1154 struct btrfs_key *location)
1156 struct inode *inode;
1160 inode = read_one_inode(root, location->objectid);
1164 dir = read_one_inode(root, dirid);
1169 ret = btrfs_add_link(trans, dir, inode, name, name_len, 1, index);
1171 /* FIXME, put inode into FIXUP list */
1179 * take a single entry in a log directory item and replay it into
1182 * if a conflicting item exists in the subdirectory already,
1183 * the inode it points to is unlinked and put into the link count
1186 * If a name from the log points to a file or directory that does
1187 * not exist in the FS, it is skipped. fsyncs on directories
1188 * do not force down inodes inside that directory, just changes to the
1189 * names or unlinks in a directory.
1191 static noinline int replay_one_name(struct btrfs_trans_handle *trans,
1192 struct btrfs_root *root,
1193 struct btrfs_path *path,
1194 struct extent_buffer *eb,
1195 struct btrfs_dir_item *di,
1196 struct btrfs_key *key)
1200 struct btrfs_dir_item *dst_di;
1201 struct btrfs_key found_key;
1202 struct btrfs_key log_key;
1208 dir = read_one_inode(root, key->objectid);
1212 name_len = btrfs_dir_name_len(eb, di);
1213 name = kmalloc(name_len, GFP_NOFS);
1217 log_type = btrfs_dir_type(eb, di);
1218 read_extent_buffer(eb, name, (unsigned long)(di + 1),
1221 btrfs_dir_item_key_to_cpu(eb, di, &log_key);
1222 exists = btrfs_lookup_inode(trans, root, path, &log_key, 0);
1227 btrfs_release_path(path);
1229 if (key->type == BTRFS_DIR_ITEM_KEY) {
1230 dst_di = btrfs_lookup_dir_item(trans, root, path, key->objectid,
1232 } else if (key->type == BTRFS_DIR_INDEX_KEY) {
1233 dst_di = btrfs_lookup_dir_index_item(trans, root, path,
1240 if (IS_ERR_OR_NULL(dst_di)) {
1241 /* we need a sequence number to insert, so we only
1242 * do inserts for the BTRFS_DIR_INDEX_KEY types
1244 if (key->type != BTRFS_DIR_INDEX_KEY)
1249 btrfs_dir_item_key_to_cpu(path->nodes[0], dst_di, &found_key);
1250 /* the existing item matches the logged item */
1251 if (found_key.objectid == log_key.objectid &&
1252 found_key.type == log_key.type &&
1253 found_key.offset == log_key.offset &&
1254 btrfs_dir_type(path->nodes[0], dst_di) == log_type) {
1259 * don't drop the conflicting directory entry if the inode
1260 * for the new entry doesn't exist
1265 ret = drop_one_dir_item(trans, root, path, dir, dst_di);
1268 if (key->type == BTRFS_DIR_INDEX_KEY)
1271 btrfs_release_path(path);
1277 btrfs_release_path(path);
1278 ret = insert_one_name(trans, root, path, key->objectid, key->offset,
1279 name, name_len, log_type, &log_key);
1281 BUG_ON(ret && ret != -ENOENT);
1286 * find all the names in a directory item and reconcile them into
1287 * the subvolume. Only BTRFS_DIR_ITEM_KEY types will have more than
1288 * one name in a directory item, but the same code gets used for
1289 * both directory index types
1291 static noinline int replay_one_dir_item(struct btrfs_trans_handle *trans,
1292 struct btrfs_root *root,
1293 struct btrfs_path *path,
1294 struct extent_buffer *eb, int slot,
1295 struct btrfs_key *key)
1298 u32 item_size = btrfs_item_size_nr(eb, slot);
1299 struct btrfs_dir_item *di;
1302 unsigned long ptr_end;
1304 ptr = btrfs_item_ptr_offset(eb, slot);
1305 ptr_end = ptr + item_size;
1306 while (ptr < ptr_end) {
1307 di = (struct btrfs_dir_item *)ptr;
1308 if (verify_dir_item(root, eb, di))
1310 name_len = btrfs_dir_name_len(eb, di);
1311 ret = replay_one_name(trans, root, path, eb, di, key);
1313 ptr = (unsigned long)(di + 1);
1320 * directory replay has two parts. There are the standard directory
1321 * items in the log copied from the subvolume, and range items
1322 * created in the log while the subvolume was logged.
1324 * The range items tell us which parts of the key space the log
1325 * is authoritative for. During replay, if a key in the subvolume
1326 * directory is in a logged range item, but not actually in the log
1327 * that means it was deleted from the directory before the fsync
1328 * and should be removed.
1330 static noinline int find_dir_range(struct btrfs_root *root,
1331 struct btrfs_path *path,
1332 u64 dirid, int key_type,
1333 u64 *start_ret, u64 *end_ret)
1335 struct btrfs_key key;
1337 struct btrfs_dir_log_item *item;
1341 if (*start_ret == (u64)-1)
1344 key.objectid = dirid;
1345 key.type = key_type;
1346 key.offset = *start_ret;
1348 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1352 if (path->slots[0] == 0)
1357 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1359 if (key.type != key_type || key.objectid != dirid) {
1363 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
1364 struct btrfs_dir_log_item);
1365 found_end = btrfs_dir_log_end(path->nodes[0], item);
1367 if (*start_ret >= key.offset && *start_ret <= found_end) {
1369 *start_ret = key.offset;
1370 *end_ret = found_end;
1375 /* check the next slot in the tree to see if it is a valid item */
1376 nritems = btrfs_header_nritems(path->nodes[0]);
1377 if (path->slots[0] >= nritems) {
1378 ret = btrfs_next_leaf(root, path);
1385 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1387 if (key.type != key_type || key.objectid != dirid) {
1391 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
1392 struct btrfs_dir_log_item);
1393 found_end = btrfs_dir_log_end(path->nodes[0], item);
1394 *start_ret = key.offset;
1395 *end_ret = found_end;
1398 btrfs_release_path(path);
1403 * this looks for a given directory item in the log. If the directory
1404 * item is not in the log, the item is removed and the inode it points
1407 static noinline int check_item_in_log(struct btrfs_trans_handle *trans,
1408 struct btrfs_root *root,
1409 struct btrfs_root *log,
1410 struct btrfs_path *path,
1411 struct btrfs_path *log_path,
1413 struct btrfs_key *dir_key)
1416 struct extent_buffer *eb;
1419 struct btrfs_dir_item *di;
1420 struct btrfs_dir_item *log_di;
1423 unsigned long ptr_end;
1425 struct inode *inode;
1426 struct btrfs_key location;
1429 eb = path->nodes[0];
1430 slot = path->slots[0];
1431 item_size = btrfs_item_size_nr(eb, slot);
1432 ptr = btrfs_item_ptr_offset(eb, slot);
1433 ptr_end = ptr + item_size;
1434 while (ptr < ptr_end) {
1435 di = (struct btrfs_dir_item *)ptr;
1436 if (verify_dir_item(root, eb, di)) {
1441 name_len = btrfs_dir_name_len(eb, di);
1442 name = kmalloc(name_len, GFP_NOFS);
1447 read_extent_buffer(eb, name, (unsigned long)(di + 1),
1450 if (log && dir_key->type == BTRFS_DIR_ITEM_KEY) {
1451 log_di = btrfs_lookup_dir_item(trans, log, log_path,
1454 } else if (log && dir_key->type == BTRFS_DIR_INDEX_KEY) {
1455 log_di = btrfs_lookup_dir_index_item(trans, log,
1461 if (IS_ERR_OR_NULL(log_di)) {
1462 btrfs_dir_item_key_to_cpu(eb, di, &location);
1463 btrfs_release_path(path);
1464 btrfs_release_path(log_path);
1465 inode = read_one_inode(root, location.objectid);
1471 ret = link_to_fixup_dir(trans, root,
1472 path, location.objectid);
1474 btrfs_inc_nlink(inode);
1475 ret = btrfs_unlink_inode(trans, root, dir, inode,
1481 /* there might still be more names under this key
1482 * check and repeat if required
1484 ret = btrfs_search_slot(NULL, root, dir_key, path,
1491 btrfs_release_path(log_path);
1494 ptr = (unsigned long)(di + 1);
1499 btrfs_release_path(path);
1500 btrfs_release_path(log_path);
1505 * deletion replay happens before we copy any new directory items
1506 * out of the log or out of backreferences from inodes. It
1507 * scans the log to find ranges of keys that log is authoritative for,
1508 * and then scans the directory to find items in those ranges that are
1509 * not present in the log.
1511 * Anything we don't find in the log is unlinked and removed from the
1514 static noinline int replay_dir_deletes(struct btrfs_trans_handle *trans,
1515 struct btrfs_root *root,
1516 struct btrfs_root *log,
1517 struct btrfs_path *path,
1518 u64 dirid, int del_all)
1522 int key_type = BTRFS_DIR_LOG_ITEM_KEY;
1524 struct btrfs_key dir_key;
1525 struct btrfs_key found_key;
1526 struct btrfs_path *log_path;
1529 dir_key.objectid = dirid;
1530 dir_key.type = BTRFS_DIR_ITEM_KEY;
1531 log_path = btrfs_alloc_path();
1535 dir = read_one_inode(root, dirid);
1536 /* it isn't an error if the inode isn't there, that can happen
1537 * because we replay the deletes before we copy in the inode item
1541 btrfs_free_path(log_path);
1549 range_end = (u64)-1;
1551 ret = find_dir_range(log, path, dirid, key_type,
1552 &range_start, &range_end);
1557 dir_key.offset = range_start;
1560 ret = btrfs_search_slot(NULL, root, &dir_key, path,
1565 nritems = btrfs_header_nritems(path->nodes[0]);
1566 if (path->slots[0] >= nritems) {
1567 ret = btrfs_next_leaf(root, path);
1571 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1573 if (found_key.objectid != dirid ||
1574 found_key.type != dir_key.type)
1577 if (found_key.offset > range_end)
1580 ret = check_item_in_log(trans, root, log, path,
1584 if (found_key.offset == (u64)-1)
1586 dir_key.offset = found_key.offset + 1;
1588 btrfs_release_path(path);
1589 if (range_end == (u64)-1)
1591 range_start = range_end + 1;
1596 if (key_type == BTRFS_DIR_LOG_ITEM_KEY) {
1597 key_type = BTRFS_DIR_LOG_INDEX_KEY;
1598 dir_key.type = BTRFS_DIR_INDEX_KEY;
1599 btrfs_release_path(path);
1603 btrfs_release_path(path);
1604 btrfs_free_path(log_path);
1610 * the process_func used to replay items from the log tree. This
1611 * gets called in two different stages. The first stage just looks
1612 * for inodes and makes sure they are all copied into the subvolume.
1614 * The second stage copies all the other item types from the log into
1615 * the subvolume. The two stage approach is slower, but gets rid of
1616 * lots of complexity around inodes referencing other inodes that exist
1617 * only in the log (references come from either directory items or inode
1620 static int replay_one_buffer(struct btrfs_root *log, struct extent_buffer *eb,
1621 struct walk_control *wc, u64 gen)
1624 struct btrfs_path *path;
1625 struct btrfs_root *root = wc->replay_dest;
1626 struct btrfs_key key;
1631 btrfs_read_buffer(eb, gen);
1633 level = btrfs_header_level(eb);
1638 path = btrfs_alloc_path();
1642 nritems = btrfs_header_nritems(eb);
1643 for (i = 0; i < nritems; i++) {
1644 btrfs_item_key_to_cpu(eb, &key, i);
1646 /* inode keys are done during the first stage */
1647 if (key.type == BTRFS_INODE_ITEM_KEY &&
1648 wc->stage == LOG_WALK_REPLAY_INODES) {
1649 struct btrfs_inode_item *inode_item;
1652 inode_item = btrfs_item_ptr(eb, i,
1653 struct btrfs_inode_item);
1654 mode = btrfs_inode_mode(eb, inode_item);
1655 if (S_ISDIR(mode)) {
1656 ret = replay_dir_deletes(wc->trans,
1657 root, log, path, key.objectid, 0);
1660 ret = overwrite_item(wc->trans, root, path,
1664 /* for regular files, make sure corresponding
1665 * orhpan item exist. extents past the new EOF
1666 * will be truncated later by orphan cleanup.
1668 if (S_ISREG(mode)) {
1669 ret = insert_orphan_item(wc->trans, root,
1674 ret = link_to_fixup_dir(wc->trans, root,
1675 path, key.objectid);
1678 if (wc->stage < LOG_WALK_REPLAY_ALL)
1681 /* these keys are simply copied */
1682 if (key.type == BTRFS_XATTR_ITEM_KEY) {
1683 ret = overwrite_item(wc->trans, root, path,
1686 } else if (key.type == BTRFS_INODE_REF_KEY) {
1687 ret = add_inode_ref(wc->trans, root, log, path,
1689 BUG_ON(ret && ret != -ENOENT);
1690 } else if (key.type == BTRFS_EXTENT_DATA_KEY) {
1691 ret = replay_one_extent(wc->trans, root, path,
1694 } else if (key.type == BTRFS_DIR_ITEM_KEY ||
1695 key.type == BTRFS_DIR_INDEX_KEY) {
1696 ret = replay_one_dir_item(wc->trans, root, path,
1701 btrfs_free_path(path);
1705 static noinline int walk_down_log_tree(struct btrfs_trans_handle *trans,
1706 struct btrfs_root *root,
1707 struct btrfs_path *path, int *level,
1708 struct walk_control *wc)
1713 struct extent_buffer *next;
1714 struct extent_buffer *cur;
1715 struct extent_buffer *parent;
1719 WARN_ON(*level < 0);
1720 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1722 while (*level > 0) {
1723 WARN_ON(*level < 0);
1724 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1725 cur = path->nodes[*level];
1727 if (btrfs_header_level(cur) != *level)
1730 if (path->slots[*level] >=
1731 btrfs_header_nritems(cur))
1734 bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
1735 ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
1736 blocksize = btrfs_level_size(root, *level - 1);
1738 parent = path->nodes[*level];
1739 root_owner = btrfs_header_owner(parent);
1741 next = btrfs_find_create_tree_block(root, bytenr, blocksize);
1746 ret = wc->process_func(root, next, wc, ptr_gen);
1750 path->slots[*level]++;
1752 btrfs_read_buffer(next, ptr_gen);
1754 btrfs_tree_lock(next);
1755 btrfs_set_lock_blocking(next);
1756 clean_tree_block(trans, root, next);
1757 btrfs_wait_tree_block_writeback(next);
1758 btrfs_tree_unlock(next);
1760 WARN_ON(root_owner !=
1761 BTRFS_TREE_LOG_OBJECTID);
1762 ret = btrfs_free_and_pin_reserved_extent(root,
1764 BUG_ON(ret); /* -ENOMEM or logic errors */
1766 free_extent_buffer(next);
1769 btrfs_read_buffer(next, ptr_gen);
1771 WARN_ON(*level <= 0);
1772 if (path->nodes[*level-1])
1773 free_extent_buffer(path->nodes[*level-1]);
1774 path->nodes[*level-1] = next;
1775 *level = btrfs_header_level(next);
1776 path->slots[*level] = 0;
1779 WARN_ON(*level < 0);
1780 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1782 path->slots[*level] = btrfs_header_nritems(path->nodes[*level]);
1788 static noinline int walk_up_log_tree(struct btrfs_trans_handle *trans,
1789 struct btrfs_root *root,
1790 struct btrfs_path *path, int *level,
1791 struct walk_control *wc)
1798 for (i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
1799 slot = path->slots[i];
1800 if (slot + 1 < btrfs_header_nritems(path->nodes[i])) {
1803 WARN_ON(*level == 0);
1806 struct extent_buffer *parent;
1807 if (path->nodes[*level] == root->node)
1808 parent = path->nodes[*level];
1810 parent = path->nodes[*level + 1];
1812 root_owner = btrfs_header_owner(parent);
1813 ret = wc->process_func(root, path->nodes[*level], wc,
1814 btrfs_header_generation(path->nodes[*level]));
1819 struct extent_buffer *next;
1821 next = path->nodes[*level];
1823 btrfs_tree_lock(next);
1824 btrfs_set_lock_blocking(next);
1825 clean_tree_block(trans, root, next);
1826 btrfs_wait_tree_block_writeback(next);
1827 btrfs_tree_unlock(next);
1829 WARN_ON(root_owner != BTRFS_TREE_LOG_OBJECTID);
1830 ret = btrfs_free_and_pin_reserved_extent(root,
1831 path->nodes[*level]->start,
1832 path->nodes[*level]->len);
1835 free_extent_buffer(path->nodes[*level]);
1836 path->nodes[*level] = NULL;
1844 * drop the reference count on the tree rooted at 'snap'. This traverses
1845 * the tree freeing any blocks that have a ref count of zero after being
1848 static int walk_log_tree(struct btrfs_trans_handle *trans,
1849 struct btrfs_root *log, struct walk_control *wc)
1854 struct btrfs_path *path;
1858 path = btrfs_alloc_path();
1862 level = btrfs_header_level(log->node);
1864 path->nodes[level] = log->node;
1865 extent_buffer_get(log->node);
1866 path->slots[level] = 0;
1869 wret = walk_down_log_tree(trans, log, path, &level, wc);
1877 wret = walk_up_log_tree(trans, log, path, &level, wc);
1886 /* was the root node processed? if not, catch it here */
1887 if (path->nodes[orig_level]) {
1888 ret = wc->process_func(log, path->nodes[orig_level], wc,
1889 btrfs_header_generation(path->nodes[orig_level]));
1893 struct extent_buffer *next;
1895 next = path->nodes[orig_level];
1897 btrfs_tree_lock(next);
1898 btrfs_set_lock_blocking(next);
1899 clean_tree_block(trans, log, next);
1900 btrfs_wait_tree_block_writeback(next);
1901 btrfs_tree_unlock(next);
1903 WARN_ON(log->root_key.objectid !=
1904 BTRFS_TREE_LOG_OBJECTID);
1905 ret = btrfs_free_and_pin_reserved_extent(log, next->start,
1907 BUG_ON(ret); /* -ENOMEM or logic errors */
1912 for (i = 0; i <= orig_level; i++) {
1913 if (path->nodes[i]) {
1914 free_extent_buffer(path->nodes[i]);
1915 path->nodes[i] = NULL;
1918 btrfs_free_path(path);
1923 * helper function to update the item for a given subvolumes log root
1924 * in the tree of log roots
1926 static int update_log_root(struct btrfs_trans_handle *trans,
1927 struct btrfs_root *log)
1931 if (log->log_transid == 1) {
1932 /* insert root item on the first sync */
1933 ret = btrfs_insert_root(trans, log->fs_info->log_root_tree,
1934 &log->root_key, &log->root_item);
1936 ret = btrfs_update_root(trans, log->fs_info->log_root_tree,
1937 &log->root_key, &log->root_item);
1942 static int wait_log_commit(struct btrfs_trans_handle *trans,
1943 struct btrfs_root *root, unsigned long transid)
1946 int index = transid % 2;
1949 * we only allow two pending log transactions at a time,
1950 * so we know that if ours is more than 2 older than the
1951 * current transaction, we're done
1954 prepare_to_wait(&root->log_commit_wait[index],
1955 &wait, TASK_UNINTERRUPTIBLE);
1956 mutex_unlock(&root->log_mutex);
1958 if (root->fs_info->last_trans_log_full_commit !=
1959 trans->transid && root->log_transid < transid + 2 &&
1960 atomic_read(&root->log_commit[index]))
1963 finish_wait(&root->log_commit_wait[index], &wait);
1964 mutex_lock(&root->log_mutex);
1965 } while (root->fs_info->last_trans_log_full_commit !=
1966 trans->transid && root->log_transid < transid + 2 &&
1967 atomic_read(&root->log_commit[index]));
1971 static void wait_for_writer(struct btrfs_trans_handle *trans,
1972 struct btrfs_root *root)
1975 while (root->fs_info->last_trans_log_full_commit !=
1976 trans->transid && atomic_read(&root->log_writers)) {
1977 prepare_to_wait(&root->log_writer_wait,
1978 &wait, TASK_UNINTERRUPTIBLE);
1979 mutex_unlock(&root->log_mutex);
1980 if (root->fs_info->last_trans_log_full_commit !=
1981 trans->transid && atomic_read(&root->log_writers))
1983 mutex_lock(&root->log_mutex);
1984 finish_wait(&root->log_writer_wait, &wait);
1989 * btrfs_sync_log does sends a given tree log down to the disk and
1990 * updates the super blocks to record it. When this call is done,
1991 * you know that any inodes previously logged are safely on disk only
1994 * Any other return value means you need to call btrfs_commit_transaction.
1995 * Some of the edge cases for fsyncing directories that have had unlinks
1996 * or renames done in the past mean that sometimes the only safe
1997 * fsync is to commit the whole FS. When btrfs_sync_log returns -EAGAIN,
1998 * that has happened.
2000 int btrfs_sync_log(struct btrfs_trans_handle *trans,
2001 struct btrfs_root *root)
2007 struct btrfs_root *log = root->log_root;
2008 struct btrfs_root *log_root_tree = root->fs_info->log_root_tree;
2009 unsigned long log_transid = 0;
2011 mutex_lock(&root->log_mutex);
2012 index1 = root->log_transid % 2;
2013 if (atomic_read(&root->log_commit[index1])) {
2014 wait_log_commit(trans, root, root->log_transid);
2015 mutex_unlock(&root->log_mutex);
2018 atomic_set(&root->log_commit[index1], 1);
2020 /* wait for previous tree log sync to complete */
2021 if (atomic_read(&root->log_commit[(index1 + 1) % 2]))
2022 wait_log_commit(trans, root, root->log_transid - 1);
2024 unsigned long batch = root->log_batch;
2025 /* when we're on an ssd, just kick the log commit out */
2026 if (!btrfs_test_opt(root, SSD) && root->log_multiple_pids) {
2027 mutex_unlock(&root->log_mutex);
2028 schedule_timeout_uninterruptible(1);
2029 mutex_lock(&root->log_mutex);
2031 wait_for_writer(trans, root);
2032 if (batch == root->log_batch)
2036 /* bail out if we need to do a full commit */
2037 if (root->fs_info->last_trans_log_full_commit == trans->transid) {
2039 mutex_unlock(&root->log_mutex);
2043 log_transid = root->log_transid;
2044 if (log_transid % 2 == 0)
2045 mark = EXTENT_DIRTY;
2049 /* we start IO on all the marked extents here, but we don't actually
2050 * wait for them until later.
2052 ret = btrfs_write_marked_extents(log, &log->dirty_log_pages, mark);
2054 btrfs_abort_transaction(trans, root, ret);
2055 mutex_unlock(&root->log_mutex);
2059 btrfs_set_root_node(&log->root_item, log->node);
2061 root->log_batch = 0;
2062 root->log_transid++;
2063 log->log_transid = root->log_transid;
2064 root->log_start_pid = 0;
2067 * IO has been started, blocks of the log tree have WRITTEN flag set
2068 * in their headers. new modifications of the log will be written to
2069 * new positions. so it's safe to allow log writers to go in.
2071 mutex_unlock(&root->log_mutex);
2073 mutex_lock(&log_root_tree->log_mutex);
2074 log_root_tree->log_batch++;
2075 atomic_inc(&log_root_tree->log_writers);
2076 mutex_unlock(&log_root_tree->log_mutex);
2078 ret = update_log_root(trans, log);
2080 mutex_lock(&log_root_tree->log_mutex);
2081 if (atomic_dec_and_test(&log_root_tree->log_writers)) {
2083 if (waitqueue_active(&log_root_tree->log_writer_wait))
2084 wake_up(&log_root_tree->log_writer_wait);
2088 if (ret != -ENOSPC) {
2089 btrfs_abort_transaction(trans, root, ret);
2090 mutex_unlock(&log_root_tree->log_mutex);
2093 root->fs_info->last_trans_log_full_commit = trans->transid;
2094 btrfs_wait_marked_extents(log, &log->dirty_log_pages, mark);
2095 mutex_unlock(&log_root_tree->log_mutex);
2100 index2 = log_root_tree->log_transid % 2;
2101 if (atomic_read(&log_root_tree->log_commit[index2])) {
2102 btrfs_wait_marked_extents(log, &log->dirty_log_pages, mark);
2103 wait_log_commit(trans, log_root_tree,
2104 log_root_tree->log_transid);
2105 mutex_unlock(&log_root_tree->log_mutex);
2109 atomic_set(&log_root_tree->log_commit[index2], 1);
2111 if (atomic_read(&log_root_tree->log_commit[(index2 + 1) % 2])) {
2112 wait_log_commit(trans, log_root_tree,
2113 log_root_tree->log_transid - 1);
2116 wait_for_writer(trans, log_root_tree);
2119 * now that we've moved on to the tree of log tree roots,
2120 * check the full commit flag again
2122 if (root->fs_info->last_trans_log_full_commit == trans->transid) {
2123 btrfs_wait_marked_extents(log, &log->dirty_log_pages, mark);
2124 mutex_unlock(&log_root_tree->log_mutex);
2126 goto out_wake_log_root;
2129 ret = btrfs_write_and_wait_marked_extents(log_root_tree,
2130 &log_root_tree->dirty_log_pages,
2131 EXTENT_DIRTY | EXTENT_NEW);
2133 btrfs_abort_transaction(trans, root, ret);
2134 mutex_unlock(&log_root_tree->log_mutex);
2135 goto out_wake_log_root;
2137 btrfs_wait_marked_extents(log, &log->dirty_log_pages, mark);
2139 btrfs_set_super_log_root(root->fs_info->super_for_commit,
2140 log_root_tree->node->start);
2141 btrfs_set_super_log_root_level(root->fs_info->super_for_commit,
2142 btrfs_header_level(log_root_tree->node));
2144 log_root_tree->log_batch = 0;
2145 log_root_tree->log_transid++;
2148 mutex_unlock(&log_root_tree->log_mutex);
2151 * nobody else is going to jump in and write the the ctree
2152 * super here because the log_commit atomic below is protecting
2153 * us. We must be called with a transaction handle pinning
2154 * the running transaction open, so a full commit can't hop
2155 * in and cause problems either.
2157 btrfs_scrub_pause_super(root);
2158 write_ctree_super(trans, root->fs_info->tree_root, 1);
2159 btrfs_scrub_continue_super(root);
2162 mutex_lock(&root->log_mutex);
2163 if (root->last_log_commit < log_transid)
2164 root->last_log_commit = log_transid;
2165 mutex_unlock(&root->log_mutex);
2168 atomic_set(&log_root_tree->log_commit[index2], 0);
2170 if (waitqueue_active(&log_root_tree->log_commit_wait[index2]))
2171 wake_up(&log_root_tree->log_commit_wait[index2]);
2173 atomic_set(&root->log_commit[index1], 0);
2175 if (waitqueue_active(&root->log_commit_wait[index1]))
2176 wake_up(&root->log_commit_wait[index1]);
2180 static void free_log_tree(struct btrfs_trans_handle *trans,
2181 struct btrfs_root *log)
2186 struct walk_control wc = {
2188 .process_func = process_one_buffer
2191 ret = walk_log_tree(trans, log, &wc);
2195 ret = find_first_extent_bit(&log->dirty_log_pages,
2196 0, &start, &end, EXTENT_DIRTY | EXTENT_NEW);
2200 clear_extent_bits(&log->dirty_log_pages, start, end,
2201 EXTENT_DIRTY | EXTENT_NEW, GFP_NOFS);
2204 free_extent_buffer(log->node);
2209 * free all the extents used by the tree log. This should be called
2210 * at commit time of the full transaction
2212 int btrfs_free_log(struct btrfs_trans_handle *trans, struct btrfs_root *root)
2214 if (root->log_root) {
2215 free_log_tree(trans, root->log_root);
2216 root->log_root = NULL;
2221 int btrfs_free_log_root_tree(struct btrfs_trans_handle *trans,
2222 struct btrfs_fs_info *fs_info)
2224 if (fs_info->log_root_tree) {
2225 free_log_tree(trans, fs_info->log_root_tree);
2226 fs_info->log_root_tree = NULL;
2232 * If both a file and directory are logged, and unlinks or renames are
2233 * mixed in, we have a few interesting corners:
2235 * create file X in dir Y
2236 * link file X to X.link in dir Y
2238 * unlink file X but leave X.link
2241 * After a crash we would expect only X.link to exist. But file X
2242 * didn't get fsync'd again so the log has back refs for X and X.link.
2244 * We solve this by removing directory entries and inode backrefs from the
2245 * log when a file that was logged in the current transaction is
2246 * unlinked. Any later fsync will include the updated log entries, and
2247 * we'll be able to reconstruct the proper directory items from backrefs.
2249 * This optimizations allows us to avoid relogging the entire inode
2250 * or the entire directory.
2252 int btrfs_del_dir_entries_in_log(struct btrfs_trans_handle *trans,
2253 struct btrfs_root *root,
2254 const char *name, int name_len,
2255 struct inode *dir, u64 index)
2257 struct btrfs_root *log;
2258 struct btrfs_dir_item *di;
2259 struct btrfs_path *path;
2263 u64 dir_ino = btrfs_ino(dir);
2265 if (BTRFS_I(dir)->logged_trans < trans->transid)
2268 ret = join_running_log_trans(root);
2272 mutex_lock(&BTRFS_I(dir)->log_mutex);
2274 log = root->log_root;
2275 path = btrfs_alloc_path();
2281 di = btrfs_lookup_dir_item(trans, log, path, dir_ino,
2282 name, name_len, -1);
2288 ret = btrfs_delete_one_dir_name(trans, log, path, di);
2289 bytes_del += name_len;
2292 btrfs_release_path(path);
2293 di = btrfs_lookup_dir_index_item(trans, log, path, dir_ino,
2294 index, name, name_len, -1);
2300 ret = btrfs_delete_one_dir_name(trans, log, path, di);
2301 bytes_del += name_len;
2305 /* update the directory size in the log to reflect the names
2309 struct btrfs_key key;
2311 key.objectid = dir_ino;
2313 key.type = BTRFS_INODE_ITEM_KEY;
2314 btrfs_release_path(path);
2316 ret = btrfs_search_slot(trans, log, &key, path, 0, 1);
2322 struct btrfs_inode_item *item;
2325 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2326 struct btrfs_inode_item);
2327 i_size = btrfs_inode_size(path->nodes[0], item);
2328 if (i_size > bytes_del)
2329 i_size -= bytes_del;
2332 btrfs_set_inode_size(path->nodes[0], item, i_size);
2333 btrfs_mark_buffer_dirty(path->nodes[0]);
2336 btrfs_release_path(path);
2339 btrfs_free_path(path);
2341 mutex_unlock(&BTRFS_I(dir)->log_mutex);
2342 if (ret == -ENOSPC) {
2343 root->fs_info->last_trans_log_full_commit = trans->transid;
2346 btrfs_abort_transaction(trans, root, ret);
2348 btrfs_end_log_trans(root);
2353 /* see comments for btrfs_del_dir_entries_in_log */
2354 int btrfs_del_inode_ref_in_log(struct btrfs_trans_handle *trans,
2355 struct btrfs_root *root,
2356 const char *name, int name_len,
2357 struct inode *inode, u64 dirid)
2359 struct btrfs_root *log;
2363 if (BTRFS_I(inode)->logged_trans < trans->transid)
2366 ret = join_running_log_trans(root);
2369 log = root->log_root;
2370 mutex_lock(&BTRFS_I(inode)->log_mutex);
2372 ret = btrfs_del_inode_ref(trans, log, name, name_len, btrfs_ino(inode),
2374 mutex_unlock(&BTRFS_I(inode)->log_mutex);
2375 if (ret == -ENOSPC) {
2376 root->fs_info->last_trans_log_full_commit = trans->transid;
2378 } else if (ret < 0 && ret != -ENOENT)
2379 btrfs_abort_transaction(trans, root, ret);
2380 btrfs_end_log_trans(root);
2386 * creates a range item in the log for 'dirid'. first_offset and
2387 * last_offset tell us which parts of the key space the log should
2388 * be considered authoritative for.
2390 static noinline int insert_dir_log_key(struct btrfs_trans_handle *trans,
2391 struct btrfs_root *log,
2392 struct btrfs_path *path,
2393 int key_type, u64 dirid,
2394 u64 first_offset, u64 last_offset)
2397 struct btrfs_key key;
2398 struct btrfs_dir_log_item *item;
2400 key.objectid = dirid;
2401 key.offset = first_offset;
2402 if (key_type == BTRFS_DIR_ITEM_KEY)
2403 key.type = BTRFS_DIR_LOG_ITEM_KEY;
2405 key.type = BTRFS_DIR_LOG_INDEX_KEY;
2406 ret = btrfs_insert_empty_item(trans, log, path, &key, sizeof(*item));
2410 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2411 struct btrfs_dir_log_item);
2412 btrfs_set_dir_log_end(path->nodes[0], item, last_offset);
2413 btrfs_mark_buffer_dirty(path->nodes[0]);
2414 btrfs_release_path(path);
2419 * log all the items included in the current transaction for a given
2420 * directory. This also creates the range items in the log tree required
2421 * to replay anything deleted before the fsync
2423 static noinline int log_dir_items(struct btrfs_trans_handle *trans,
2424 struct btrfs_root *root, struct inode *inode,
2425 struct btrfs_path *path,
2426 struct btrfs_path *dst_path, int key_type,
2427 u64 min_offset, u64 *last_offset_ret)
2429 struct btrfs_key min_key;
2430 struct btrfs_key max_key;
2431 struct btrfs_root *log = root->log_root;
2432 struct extent_buffer *src;
2437 u64 first_offset = min_offset;
2438 u64 last_offset = (u64)-1;
2439 u64 ino = btrfs_ino(inode);
2441 log = root->log_root;
2442 max_key.objectid = ino;
2443 max_key.offset = (u64)-1;
2444 max_key.type = key_type;
2446 min_key.objectid = ino;
2447 min_key.type = key_type;
2448 min_key.offset = min_offset;
2450 path->keep_locks = 1;
2452 ret = btrfs_search_forward(root, &min_key, &max_key,
2453 path, 0, trans->transid);
2456 * we didn't find anything from this transaction, see if there
2457 * is anything at all
2459 if (ret != 0 || min_key.objectid != ino || min_key.type != key_type) {
2460 min_key.objectid = ino;
2461 min_key.type = key_type;
2462 min_key.offset = (u64)-1;
2463 btrfs_release_path(path);
2464 ret = btrfs_search_slot(NULL, root, &min_key, path, 0, 0);
2466 btrfs_release_path(path);
2469 ret = btrfs_previous_item(root, path, ino, key_type);
2471 /* if ret == 0 there are items for this type,
2472 * create a range to tell us the last key of this type.
2473 * otherwise, there are no items in this directory after
2474 * *min_offset, and we create a range to indicate that.
2477 struct btrfs_key tmp;
2478 btrfs_item_key_to_cpu(path->nodes[0], &tmp,
2480 if (key_type == tmp.type)
2481 first_offset = max(min_offset, tmp.offset) + 1;
2486 /* go backward to find any previous key */
2487 ret = btrfs_previous_item(root, path, ino, key_type);
2489 struct btrfs_key tmp;
2490 btrfs_item_key_to_cpu(path->nodes[0], &tmp, path->slots[0]);
2491 if (key_type == tmp.type) {
2492 first_offset = tmp.offset;
2493 ret = overwrite_item(trans, log, dst_path,
2494 path->nodes[0], path->slots[0],
2502 btrfs_release_path(path);
2504 /* find the first key from this transaction again */
2505 ret = btrfs_search_slot(NULL, root, &min_key, path, 0, 0);
2512 * we have a block from this transaction, log every item in it
2513 * from our directory
2516 struct btrfs_key tmp;
2517 src = path->nodes[0];
2518 nritems = btrfs_header_nritems(src);
2519 for (i = path->slots[0]; i < nritems; i++) {
2520 btrfs_item_key_to_cpu(src, &min_key, i);
2522 if (min_key.objectid != ino || min_key.type != key_type)
2524 ret = overwrite_item(trans, log, dst_path, src, i,
2531 path->slots[0] = nritems;
2534 * look ahead to the next item and see if it is also
2535 * from this directory and from this transaction
2537 ret = btrfs_next_leaf(root, path);
2539 last_offset = (u64)-1;
2542 btrfs_item_key_to_cpu(path->nodes[0], &tmp, path->slots[0]);
2543 if (tmp.objectid != ino || tmp.type != key_type) {
2544 last_offset = (u64)-1;
2547 if (btrfs_header_generation(path->nodes[0]) != trans->transid) {
2548 ret = overwrite_item(trans, log, dst_path,
2549 path->nodes[0], path->slots[0],
2554 last_offset = tmp.offset;
2559 btrfs_release_path(path);
2560 btrfs_release_path(dst_path);
2563 *last_offset_ret = last_offset;
2565 * insert the log range keys to indicate where the log
2568 ret = insert_dir_log_key(trans, log, path, key_type,
2569 ino, first_offset, last_offset);
2577 * logging directories is very similar to logging inodes, We find all the items
2578 * from the current transaction and write them to the log.
2580 * The recovery code scans the directory in the subvolume, and if it finds a
2581 * key in the range logged that is not present in the log tree, then it means
2582 * that dir entry was unlinked during the transaction.
2584 * In order for that scan to work, we must include one key smaller than
2585 * the smallest logged by this transaction and one key larger than the largest
2586 * key logged by this transaction.
2588 static noinline int log_directory_changes(struct btrfs_trans_handle *trans,
2589 struct btrfs_root *root, struct inode *inode,
2590 struct btrfs_path *path,
2591 struct btrfs_path *dst_path)
2596 int key_type = BTRFS_DIR_ITEM_KEY;
2602 ret = log_dir_items(trans, root, inode, path,
2603 dst_path, key_type, min_key,
2607 if (max_key == (u64)-1)
2609 min_key = max_key + 1;
2612 if (key_type == BTRFS_DIR_ITEM_KEY) {
2613 key_type = BTRFS_DIR_INDEX_KEY;
2620 * a helper function to drop items from the log before we relog an
2621 * inode. max_key_type indicates the highest item type to remove.
2622 * This cannot be run for file data extents because it does not
2623 * free the extents they point to.
2625 static int drop_objectid_items(struct btrfs_trans_handle *trans,
2626 struct btrfs_root *log,
2627 struct btrfs_path *path,
2628 u64 objectid, int max_key_type)
2631 struct btrfs_key key;
2632 struct btrfs_key found_key;
2634 key.objectid = objectid;
2635 key.type = max_key_type;
2636 key.offset = (u64)-1;
2639 ret = btrfs_search_slot(trans, log, &key, path, -1, 1);
2644 if (path->slots[0] == 0)
2648 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
2651 if (found_key.objectid != objectid)
2654 ret = btrfs_del_item(trans, log, path);
2657 btrfs_release_path(path);
2659 btrfs_release_path(path);
2663 static noinline int copy_items(struct btrfs_trans_handle *trans,
2664 struct btrfs_root *log,
2665 struct btrfs_path *dst_path,
2666 struct extent_buffer *src,
2667 int start_slot, int nr, int inode_only)
2669 unsigned long src_offset;
2670 unsigned long dst_offset;
2671 struct btrfs_file_extent_item *extent;
2672 struct btrfs_inode_item *inode_item;
2674 struct btrfs_key *ins_keys;
2678 struct list_head ordered_sums;
2680 INIT_LIST_HEAD(&ordered_sums);
2682 ins_data = kmalloc(nr * sizeof(struct btrfs_key) +
2683 nr * sizeof(u32), GFP_NOFS);
2687 ins_sizes = (u32 *)ins_data;
2688 ins_keys = (struct btrfs_key *)(ins_data + nr * sizeof(u32));
2690 for (i = 0; i < nr; i++) {
2691 ins_sizes[i] = btrfs_item_size_nr(src, i + start_slot);
2692 btrfs_item_key_to_cpu(src, ins_keys + i, i + start_slot);
2694 ret = btrfs_insert_empty_items(trans, log, dst_path,
2695 ins_keys, ins_sizes, nr);
2701 for (i = 0; i < nr; i++, dst_path->slots[0]++) {
2702 dst_offset = btrfs_item_ptr_offset(dst_path->nodes[0],
2703 dst_path->slots[0]);
2705 src_offset = btrfs_item_ptr_offset(src, start_slot + i);
2707 copy_extent_buffer(dst_path->nodes[0], src, dst_offset,
2708 src_offset, ins_sizes[i]);
2710 if (inode_only == LOG_INODE_EXISTS &&
2711 ins_keys[i].type == BTRFS_INODE_ITEM_KEY) {
2712 inode_item = btrfs_item_ptr(dst_path->nodes[0],
2714 struct btrfs_inode_item);
2715 btrfs_set_inode_size(dst_path->nodes[0], inode_item, 0);
2717 /* set the generation to zero so the recover code
2718 * can tell the difference between an logging
2719 * just to say 'this inode exists' and a logging
2720 * to say 'update this inode with these values'
2722 btrfs_set_inode_generation(dst_path->nodes[0],
2725 /* take a reference on file data extents so that truncates
2726 * or deletes of this inode don't have to relog the inode
2729 if (btrfs_key_type(ins_keys + i) == BTRFS_EXTENT_DATA_KEY) {
2731 extent = btrfs_item_ptr(src, start_slot + i,
2732 struct btrfs_file_extent_item);
2734 if (btrfs_file_extent_generation(src, extent) < trans->transid)
2737 found_type = btrfs_file_extent_type(src, extent);
2738 if (found_type == BTRFS_FILE_EXTENT_REG ||
2739 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
2741 ds = btrfs_file_extent_disk_bytenr(src,
2743 /* ds == 0 is a hole */
2747 dl = btrfs_file_extent_disk_num_bytes(src,
2749 cs = btrfs_file_extent_offset(src, extent);
2750 cl = btrfs_file_extent_num_bytes(src,
2752 if (btrfs_file_extent_compression(src,
2758 ret = btrfs_lookup_csums_range(
2759 log->fs_info->csum_root,
2760 ds + cs, ds + cs + cl - 1,
2767 btrfs_mark_buffer_dirty(dst_path->nodes[0]);
2768 btrfs_release_path(dst_path);
2772 * we have to do this after the loop above to avoid changing the
2773 * log tree while trying to change the log tree.
2776 while (!list_empty(&ordered_sums)) {
2777 struct btrfs_ordered_sum *sums = list_entry(ordered_sums.next,
2778 struct btrfs_ordered_sum,
2781 ret = btrfs_csum_file_blocks(trans, log, sums);
2782 list_del(&sums->list);
2788 /* log a single inode in the tree log.
2789 * At least one parent directory for this inode must exist in the tree
2790 * or be logged already.
2792 * Any items from this inode changed by the current transaction are copied
2793 * to the log tree. An extra reference is taken on any extents in this
2794 * file, allowing us to avoid a whole pile of corner cases around logging
2795 * blocks that have been removed from the tree.
2797 * See LOG_INODE_ALL and related defines for a description of what inode_only
2800 * This handles both files and directories.
2802 static int btrfs_log_inode(struct btrfs_trans_handle *trans,
2803 struct btrfs_root *root, struct inode *inode,
2806 struct btrfs_path *path;
2807 struct btrfs_path *dst_path;
2808 struct btrfs_key min_key;
2809 struct btrfs_key max_key;
2810 struct btrfs_root *log = root->log_root;
2811 struct extent_buffer *src = NULL;
2815 int ins_start_slot = 0;
2817 u64 ino = btrfs_ino(inode);
2819 log = root->log_root;
2821 path = btrfs_alloc_path();
2824 dst_path = btrfs_alloc_path();
2826 btrfs_free_path(path);
2830 min_key.objectid = ino;
2831 min_key.type = BTRFS_INODE_ITEM_KEY;
2834 max_key.objectid = ino;
2836 /* today the code can only do partial logging of directories */
2837 if (!S_ISDIR(inode->i_mode))
2838 inode_only = LOG_INODE_ALL;
2840 if (inode_only == LOG_INODE_EXISTS || S_ISDIR(inode->i_mode))
2841 max_key.type = BTRFS_XATTR_ITEM_KEY;
2843 max_key.type = (u8)-1;
2844 max_key.offset = (u64)-1;
2846 ret = btrfs_commit_inode_delayed_items(trans, inode);
2848 btrfs_free_path(path);
2849 btrfs_free_path(dst_path);
2853 mutex_lock(&BTRFS_I(inode)->log_mutex);
2856 * a brute force approach to making sure we get the most uptodate
2857 * copies of everything.
2859 if (S_ISDIR(inode->i_mode)) {
2860 int max_key_type = BTRFS_DIR_LOG_INDEX_KEY;
2862 if (inode_only == LOG_INODE_EXISTS)
2863 max_key_type = BTRFS_XATTR_ITEM_KEY;
2864 ret = drop_objectid_items(trans, log, path, ino, max_key_type);
2866 ret = btrfs_truncate_inode_items(trans, log, inode, 0, 0);
2872 path->keep_locks = 1;
2876 ret = btrfs_search_forward(root, &min_key, &max_key,
2877 path, 0, trans->transid);
2881 /* note, ins_nr might be > 0 here, cleanup outside the loop */
2882 if (min_key.objectid != ino)
2884 if (min_key.type > max_key.type)
2887 src = path->nodes[0];
2888 if (ins_nr && ins_start_slot + ins_nr == path->slots[0]) {
2891 } else if (!ins_nr) {
2892 ins_start_slot = path->slots[0];
2897 ret = copy_items(trans, log, dst_path, src, ins_start_slot,
2898 ins_nr, inode_only);
2904 ins_start_slot = path->slots[0];
2907 nritems = btrfs_header_nritems(path->nodes[0]);
2909 if (path->slots[0] < nritems) {
2910 btrfs_item_key_to_cpu(path->nodes[0], &min_key,
2915 ret = copy_items(trans, log, dst_path, src,
2917 ins_nr, inode_only);
2924 btrfs_release_path(path);
2926 if (min_key.offset < (u64)-1)
2928 else if (min_key.type < (u8)-1)
2930 else if (min_key.objectid < (u64)-1)
2936 ret = copy_items(trans, log, dst_path, src,
2938 ins_nr, inode_only);
2946 if (inode_only == LOG_INODE_ALL && S_ISDIR(inode->i_mode)) {
2947 btrfs_release_path(path);
2948 btrfs_release_path(dst_path);
2949 ret = log_directory_changes(trans, root, inode, path, dst_path);
2955 BTRFS_I(inode)->logged_trans = trans->transid;
2957 mutex_unlock(&BTRFS_I(inode)->log_mutex);
2959 btrfs_free_path(path);
2960 btrfs_free_path(dst_path);
2965 * follow the dentry parent pointers up the chain and see if any
2966 * of the directories in it require a full commit before they can
2967 * be logged. Returns zero if nothing special needs to be done or 1 if
2968 * a full commit is required.
2970 static noinline int check_parent_dirs_for_sync(struct btrfs_trans_handle *trans,
2971 struct inode *inode,
2972 struct dentry *parent,
2973 struct super_block *sb,
2977 struct btrfs_root *root;
2978 struct dentry *old_parent = NULL;
2981 * for regular files, if its inode is already on disk, we don't
2982 * have to worry about the parents at all. This is because
2983 * we can use the last_unlink_trans field to record renames
2984 * and other fun in this file.
2986 if (S_ISREG(inode->i_mode) &&
2987 BTRFS_I(inode)->generation <= last_committed &&
2988 BTRFS_I(inode)->last_unlink_trans <= last_committed)
2991 if (!S_ISDIR(inode->i_mode)) {
2992 if (!parent || !parent->d_inode || sb != parent->d_inode->i_sb)
2994 inode = parent->d_inode;
2998 BTRFS_I(inode)->logged_trans = trans->transid;
3001 if (BTRFS_I(inode)->last_unlink_trans > last_committed) {
3002 root = BTRFS_I(inode)->root;
3005 * make sure any commits to the log are forced
3006 * to be full commits
3008 root->fs_info->last_trans_log_full_commit =
3014 if (!parent || !parent->d_inode || sb != parent->d_inode->i_sb)
3017 if (IS_ROOT(parent))
3020 parent = dget_parent(parent);
3022 old_parent = parent;
3023 inode = parent->d_inode;
3031 static int inode_in_log(struct btrfs_trans_handle *trans,
3032 struct inode *inode)
3034 struct btrfs_root *root = BTRFS_I(inode)->root;
3037 mutex_lock(&root->log_mutex);
3038 if (BTRFS_I(inode)->logged_trans == trans->transid &&
3039 BTRFS_I(inode)->last_sub_trans <= root->last_log_commit)
3041 mutex_unlock(&root->log_mutex);
3047 * helper function around btrfs_log_inode to make sure newly created
3048 * parent directories also end up in the log. A minimal inode and backref
3049 * only logging is done of any parent directories that are older than
3050 * the last committed transaction
3052 int btrfs_log_inode_parent(struct btrfs_trans_handle *trans,
3053 struct btrfs_root *root, struct inode *inode,
3054 struct dentry *parent, int exists_only)
3056 int inode_only = exists_only ? LOG_INODE_EXISTS : LOG_INODE_ALL;
3057 struct super_block *sb;
3058 struct dentry *old_parent = NULL;
3060 u64 last_committed = root->fs_info->last_trans_committed;
3064 if (btrfs_test_opt(root, NOTREELOG)) {
3069 if (root->fs_info->last_trans_log_full_commit >
3070 root->fs_info->last_trans_committed) {
3075 if (root != BTRFS_I(inode)->root ||
3076 btrfs_root_refs(&root->root_item) == 0) {
3081 ret = check_parent_dirs_for_sync(trans, inode, parent,
3082 sb, last_committed);
3086 if (inode_in_log(trans, inode)) {
3087 ret = BTRFS_NO_LOG_SYNC;
3091 ret = start_log_trans(trans, root);
3095 ret = btrfs_log_inode(trans, root, inode, inode_only);
3100 * for regular files, if its inode is already on disk, we don't
3101 * have to worry about the parents at all. This is because
3102 * we can use the last_unlink_trans field to record renames
3103 * and other fun in this file.
3105 if (S_ISREG(inode->i_mode) &&
3106 BTRFS_I(inode)->generation <= last_committed &&
3107 BTRFS_I(inode)->last_unlink_trans <= last_committed) {
3112 inode_only = LOG_INODE_EXISTS;
3114 if (!parent || !parent->d_inode || sb != parent->d_inode->i_sb)
3117 inode = parent->d_inode;
3118 if (root != BTRFS_I(inode)->root)
3121 if (BTRFS_I(inode)->generation >
3122 root->fs_info->last_trans_committed) {
3123 ret = btrfs_log_inode(trans, root, inode, inode_only);
3127 if (IS_ROOT(parent))
3130 parent = dget_parent(parent);
3132 old_parent = parent;
3138 BUG_ON(ret != -ENOSPC);
3139 root->fs_info->last_trans_log_full_commit = trans->transid;
3142 btrfs_end_log_trans(root);
3148 * it is not safe to log dentry if the chunk root has added new
3149 * chunks. This returns 0 if the dentry was logged, and 1 otherwise.
3150 * If this returns 1, you must commit the transaction to safely get your
3153 int btrfs_log_dentry_safe(struct btrfs_trans_handle *trans,
3154 struct btrfs_root *root, struct dentry *dentry)
3156 struct dentry *parent = dget_parent(dentry);
3159 ret = btrfs_log_inode_parent(trans, root, dentry->d_inode, parent, 0);
3166 * should be called during mount to recover any replay any log trees
3169 int btrfs_recover_log_trees(struct btrfs_root *log_root_tree)
3172 struct btrfs_path *path;
3173 struct btrfs_trans_handle *trans;
3174 struct btrfs_key key;
3175 struct btrfs_key found_key;
3176 struct btrfs_key tmp_key;
3177 struct btrfs_root *log;
3178 struct btrfs_fs_info *fs_info = log_root_tree->fs_info;
3179 struct walk_control wc = {
3180 .process_func = process_one_buffer,
3184 path = btrfs_alloc_path();
3188 fs_info->log_root_recovering = 1;
3190 trans = btrfs_start_transaction(fs_info->tree_root, 0);
3191 if (IS_ERR(trans)) {
3192 ret = PTR_ERR(trans);
3199 ret = walk_log_tree(trans, log_root_tree, &wc);
3201 btrfs_error(fs_info, ret, "Failed to pin buffers while "
3202 "recovering log root tree.");
3207 key.objectid = BTRFS_TREE_LOG_OBJECTID;
3208 key.offset = (u64)-1;
3209 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
3212 ret = btrfs_search_slot(NULL, log_root_tree, &key, path, 0, 0);
3215 btrfs_error(fs_info, ret,
3216 "Couldn't find tree log root.");
3220 if (path->slots[0] == 0)
3224 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
3226 btrfs_release_path(path);
3227 if (found_key.objectid != BTRFS_TREE_LOG_OBJECTID)
3230 log = btrfs_read_fs_root_no_radix(log_root_tree,
3234 btrfs_error(fs_info, ret,
3235 "Couldn't read tree log root.");
3239 tmp_key.objectid = found_key.offset;
3240 tmp_key.type = BTRFS_ROOT_ITEM_KEY;
3241 tmp_key.offset = (u64)-1;
3243 wc.replay_dest = btrfs_read_fs_root_no_name(fs_info, &tmp_key);
3244 if (IS_ERR(wc.replay_dest)) {
3245 ret = PTR_ERR(wc.replay_dest);
3246 btrfs_error(fs_info, ret, "Couldn't read target root "
3247 "for tree log recovery.");
3251 wc.replay_dest->log_root = log;
3252 btrfs_record_root_in_trans(trans, wc.replay_dest);
3253 ret = walk_log_tree(trans, log, &wc);
3256 if (wc.stage == LOG_WALK_REPLAY_ALL) {
3257 ret = fixup_inode_link_counts(trans, wc.replay_dest,
3262 key.offset = found_key.offset - 1;
3263 wc.replay_dest->log_root = NULL;
3264 free_extent_buffer(log->node);
3265 free_extent_buffer(log->commit_root);
3268 if (found_key.offset == 0)
3271 btrfs_release_path(path);
3273 /* step one is to pin it all, step two is to replay just inodes */
3276 wc.process_func = replay_one_buffer;
3277 wc.stage = LOG_WALK_REPLAY_INODES;
3280 /* step three is to replay everything */
3281 if (wc.stage < LOG_WALK_REPLAY_ALL) {
3286 btrfs_free_path(path);
3288 free_extent_buffer(log_root_tree->node);
3289 log_root_tree->log_root = NULL;
3290 fs_info->log_root_recovering = 0;
3292 /* step 4: commit the transaction, which also unpins the blocks */
3293 btrfs_commit_transaction(trans, fs_info->tree_root);
3295 kfree(log_root_tree);
3299 btrfs_free_path(path);
3304 * there are some corner cases where we want to force a full
3305 * commit instead of allowing a directory to be logged.
3307 * They revolve around files there were unlinked from the directory, and
3308 * this function updates the parent directory so that a full commit is
3309 * properly done if it is fsync'd later after the unlinks are done.
3311 void btrfs_record_unlink_dir(struct btrfs_trans_handle *trans,
3312 struct inode *dir, struct inode *inode,
3316 * when we're logging a file, if it hasn't been renamed
3317 * or unlinked, and its inode is fully committed on disk,
3318 * we don't have to worry about walking up the directory chain
3319 * to log its parents.
3321 * So, we use the last_unlink_trans field to put this transid
3322 * into the file. When the file is logged we check it and
3323 * don't log the parents if the file is fully on disk.
3325 if (S_ISREG(inode->i_mode))
3326 BTRFS_I(inode)->last_unlink_trans = trans->transid;
3329 * if this directory was already logged any new
3330 * names for this file/dir will get recorded
3333 if (BTRFS_I(dir)->logged_trans == trans->transid)
3337 * if the inode we're about to unlink was logged,
3338 * the log will be properly updated for any new names
3340 if (BTRFS_I(inode)->logged_trans == trans->transid)
3344 * when renaming files across directories, if the directory
3345 * there we're unlinking from gets fsync'd later on, there's
3346 * no way to find the destination directory later and fsync it
3347 * properly. So, we have to be conservative and force commits
3348 * so the new name gets discovered.
3353 /* we can safely do the unlink without any special recording */
3357 BTRFS_I(dir)->last_unlink_trans = trans->transid;
3361 * Call this after adding a new name for a file and it will properly
3362 * update the log to reflect the new name.
3364 * It will return zero if all goes well, and it will return 1 if a
3365 * full transaction commit is required.
3367 int btrfs_log_new_name(struct btrfs_trans_handle *trans,
3368 struct inode *inode, struct inode *old_dir,
3369 struct dentry *parent)
3371 struct btrfs_root * root = BTRFS_I(inode)->root;
3374 * this will force the logging code to walk the dentry chain
3377 if (S_ISREG(inode->i_mode))
3378 BTRFS_I(inode)->last_unlink_trans = trans->transid;
3381 * if this inode hasn't been logged and directory we're renaming it
3382 * from hasn't been logged, we don't need to log it
3384 if (BTRFS_I(inode)->logged_trans <=
3385 root->fs_info->last_trans_committed &&
3386 (!old_dir || BTRFS_I(old_dir)->logged_trans <=
3387 root->fs_info->last_trans_committed))
3390 return btrfs_log_inode_parent(trans, root, inode, parent, 1);