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-rw-r--r--fs/btrfs/tree-log.c2892
1 files changed, 2892 insertions, 0 deletions
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
new file mode 100644
index 000000000000..88bbfd959f18
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+++ b/fs/btrfs/tree-log.c
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1/*
2 * Copyright (C) 2008 Oracle. All rights reserved.
3 *
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.
7 *
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.
12 *
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.
17 */
18
19#include <linux/sched.h>
20#include "ctree.h"
21#include "transaction.h"
22#include "disk-io.h"
23#include "locking.h"
24#include "print-tree.h"
25#include "compat.h"
26
27/* magic values for the inode_only field in btrfs_log_inode:
28 *
29 * LOG_INODE_ALL means to log everything
30 * LOG_INODE_EXISTS means to log just enough to recreate the inode
31 * during log replay
32 */
33#define LOG_INODE_ALL 0
34#define LOG_INODE_EXISTS 1
35
36/*
37 * stages for the tree walking. The first
38 * stage (0) is to only pin down the blocks we find
39 * the second stage (1) is to make sure that all the inodes
40 * we find in the log are created in the subvolume.
41 *
42 * The last stage is to deal with directories and links and extents
43 * and all the other fun semantics
44 */
45#define LOG_WALK_PIN_ONLY 0
46#define LOG_WALK_REPLAY_INODES 1
47#define LOG_WALK_REPLAY_ALL 2
48
49static int __btrfs_log_inode(struct btrfs_trans_handle *trans,
50 struct btrfs_root *root, struct inode *inode,
51 int inode_only);
52
53/*
54 * tree logging is a special write ahead log used to make sure that
55 * fsyncs and O_SYNCs can happen without doing full tree commits.
56 *
57 * Full tree commits are expensive because they require commonly
58 * modified blocks to be recowed, creating many dirty pages in the
59 * extent tree an 4x-6x higher write load than ext3.
60 *
61 * Instead of doing a tree commit on every fsync, we use the
62 * key ranges and transaction ids to find items for a given file or directory
63 * that have changed in this transaction. Those items are copied into
64 * a special tree (one per subvolume root), that tree is written to disk
65 * and then the fsync is considered complete.
66 *
67 * After a crash, items are copied out of the log-tree back into the
68 * subvolume tree. Any file data extents found are recorded in the extent
69 * allocation tree, and the log-tree freed.
70 *
71 * The log tree is read three times, once to pin down all the extents it is
72 * using in ram and once, once to create all the inodes logged in the tree
73 * and once to do all the other items.
74 */
75
76/*
77 * btrfs_add_log_tree adds a new per-subvolume log tree into the
78 * tree of log tree roots. This must be called with a tree log transaction
79 * running (see start_log_trans).
80 */
81int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
82 struct btrfs_root *root)
83{
84 struct btrfs_key key;
85 struct btrfs_root_item root_item;
86 struct btrfs_inode_item *inode_item;
87 struct extent_buffer *leaf;
88 struct btrfs_root *new_root = root;
89 int ret;
90 u64 objectid = root->root_key.objectid;
91
92 leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 0,
93 BTRFS_TREE_LOG_OBJECTID,
94 trans->transid, 0, 0, 0);
95 if (IS_ERR(leaf)) {
96 ret = PTR_ERR(leaf);
97 return ret;
98 }
99
100 btrfs_set_header_nritems(leaf, 0);
101 btrfs_set_header_level(leaf, 0);
102 btrfs_set_header_bytenr(leaf, leaf->start);
103 btrfs_set_header_generation(leaf, trans->transid);
104 btrfs_set_header_owner(leaf, BTRFS_TREE_LOG_OBJECTID);
105
106 write_extent_buffer(leaf, root->fs_info->fsid,
107 (unsigned long)btrfs_header_fsid(leaf),
108 BTRFS_FSID_SIZE);
109 btrfs_mark_buffer_dirty(leaf);
110
111 inode_item = &root_item.inode;
112 memset(inode_item, 0, sizeof(*inode_item));
113 inode_item->generation = cpu_to_le64(1);
114 inode_item->size = cpu_to_le64(3);
115 inode_item->nlink = cpu_to_le32(1);
116 inode_item->nblocks = cpu_to_le64(1);
117 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
118
119 btrfs_set_root_bytenr(&root_item, leaf->start);
120 btrfs_set_root_level(&root_item, 0);
121 btrfs_set_root_refs(&root_item, 0);
122 btrfs_set_root_used(&root_item, 0);
123
124 memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
125 root_item.drop_level = 0;
126
127 btrfs_tree_unlock(leaf);
128 free_extent_buffer(leaf);
129 leaf = NULL;
130
131 btrfs_set_root_dirid(&root_item, 0);
132
133 key.objectid = BTRFS_TREE_LOG_OBJECTID;
134 key.offset = objectid;
135 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
136 ret = btrfs_insert_root(trans, root->fs_info->log_root_tree, &key,
137 &root_item);
138 if (ret)
139 goto fail;
140
141 new_root = btrfs_read_fs_root_no_radix(root->fs_info->log_root_tree,
142 &key);
143 BUG_ON(!new_root);
144
145 WARN_ON(root->log_root);
146 root->log_root = new_root;
147
148 /*
149 * log trees do not get reference counted because they go away
150 * before a real commit is actually done. They do store pointers
151 * to file data extents, and those reference counts still get
152 * updated (along with back refs to the log tree).
153 */
154 new_root->ref_cows = 0;
155 new_root->last_trans = trans->transid;
156fail:
157 return ret;
158}
159
160/*
161 * start a sub transaction and setup the log tree
162 * this increments the log tree writer count to make the people
163 * syncing the tree wait for us to finish
164 */
165static int start_log_trans(struct btrfs_trans_handle *trans,
166 struct btrfs_root *root)
167{
168 int ret;
169 mutex_lock(&root->fs_info->tree_log_mutex);
170 if (!root->fs_info->log_root_tree) {
171 ret = btrfs_init_log_root_tree(trans, root->fs_info);
172 BUG_ON(ret);
173 }
174 if (!root->log_root) {
175 ret = btrfs_add_log_tree(trans, root);
176 BUG_ON(ret);
177 }
178 atomic_inc(&root->fs_info->tree_log_writers);
179 root->fs_info->tree_log_batch++;
180 mutex_unlock(&root->fs_info->tree_log_mutex);
181 return 0;
182}
183
184/*
185 * returns 0 if there was a log transaction running and we were able
186 * to join, or returns -ENOENT if there were not transactions
187 * in progress
188 */
189static int join_running_log_trans(struct btrfs_root *root)
190{
191 int ret = -ENOENT;
192
193 smp_mb();
194 if (!root->log_root)
195 return -ENOENT;
196
197 mutex_lock(&root->fs_info->tree_log_mutex);
198 if (root->log_root) {
199 ret = 0;
200 atomic_inc(&root->fs_info->tree_log_writers);
201 root->fs_info->tree_log_batch++;
202 }
203 mutex_unlock(&root->fs_info->tree_log_mutex);
204 return ret;
205}
206
207/*
208 * indicate we're done making changes to the log tree
209 * and wake up anyone waiting to do a sync
210 */
211static int end_log_trans(struct btrfs_root *root)
212{
213 atomic_dec(&root->fs_info->tree_log_writers);
214 smp_mb();
215 if (waitqueue_active(&root->fs_info->tree_log_wait))
216 wake_up(&root->fs_info->tree_log_wait);
217 return 0;
218}
219
220
221/*
222 * the walk control struct is used to pass state down the chain when
223 * processing the log tree. The stage field tells us which part
224 * of the log tree processing we are currently doing. The others
225 * are state fields used for that specific part
226 */
227struct walk_control {
228 /* should we free the extent on disk when done? This is used
229 * at transaction commit time while freeing a log tree
230 */
231 int free;
232
233 /* should we write out the extent buffer? This is used
234 * while flushing the log tree to disk during a sync
235 */
236 int write;
237
238 /* should we wait for the extent buffer io to finish? Also used
239 * while flushing the log tree to disk for a sync
240 */
241 int wait;
242
243 /* pin only walk, we record which extents on disk belong to the
244 * log trees
245 */
246 int pin;
247
248 /* what stage of the replay code we're currently in */
249 int stage;
250
251 /* the root we are currently replaying */
252 struct btrfs_root *replay_dest;
253
254 /* the trans handle for the current replay */
255 struct btrfs_trans_handle *trans;
256
257 /* the function that gets used to process blocks we find in the
258 * tree. Note the extent_buffer might not be up to date when it is
259 * passed in, and it must be checked or read if you need the data
260 * inside it
261 */
262 int (*process_func)(struct btrfs_root *log, struct extent_buffer *eb,
263 struct walk_control *wc, u64 gen);
264};
265
266/*
267 * process_func used to pin down extents, write them or wait on them
268 */
269static int process_one_buffer(struct btrfs_root *log,
270 struct extent_buffer *eb,
271 struct walk_control *wc, u64 gen)
272{
273 if (wc->pin) {
274 mutex_lock(&log->fs_info->alloc_mutex);
275 btrfs_update_pinned_extents(log->fs_info->extent_root,
276 eb->start, eb->len, 1);
277 mutex_unlock(&log->fs_info->alloc_mutex);
278 }
279
280 if (btrfs_buffer_uptodate(eb, gen)) {
281 if (wc->write)
282 btrfs_write_tree_block(eb);
283 if (wc->wait)
284 btrfs_wait_tree_block_writeback(eb);
285 }
286 return 0;
287}
288
289/*
290 * Item overwrite used by replay and tree logging. eb, slot and key all refer
291 * to the src data we are copying out.
292 *
293 * root is the tree we are copying into, and path is a scratch
294 * path for use in this function (it should be released on entry and
295 * will be released on exit).
296 *
297 * If the key is already in the destination tree the existing item is
298 * overwritten. If the existing item isn't big enough, it is extended.
299 * If it is too large, it is truncated.
300 *
301 * If the key isn't in the destination yet, a new item is inserted.
302 */
303static noinline int overwrite_item(struct btrfs_trans_handle *trans,
304 struct btrfs_root *root,
305 struct btrfs_path *path,
306 struct extent_buffer *eb, int slot,
307 struct btrfs_key *key)
308{
309 int ret;
310 u32 item_size;
311 u64 saved_i_size = 0;
312 int save_old_i_size = 0;
313 unsigned long src_ptr;
314 unsigned long dst_ptr;
315 int overwrite_root = 0;
316
317 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID)
318 overwrite_root = 1;
319
320 item_size = btrfs_item_size_nr(eb, slot);
321 src_ptr = btrfs_item_ptr_offset(eb, slot);
322
323 /* look for the key in the destination tree */
324 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
325 if (ret == 0) {
326 char *src_copy;
327 char *dst_copy;
328 u32 dst_size = btrfs_item_size_nr(path->nodes[0],
329 path->slots[0]);
330 if (dst_size != item_size)
331 goto insert;
332
333 if (item_size == 0) {
334 btrfs_release_path(root, path);
335 return 0;
336 }
337 dst_copy = kmalloc(item_size, GFP_NOFS);
338 src_copy = kmalloc(item_size, GFP_NOFS);
339
340 read_extent_buffer(eb, src_copy, src_ptr, item_size);
341
342 dst_ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
343 read_extent_buffer(path->nodes[0], dst_copy, dst_ptr,
344 item_size);
345 ret = memcmp(dst_copy, src_copy, item_size);
346
347 kfree(dst_copy);
348 kfree(src_copy);
349 /*
350 * they have the same contents, just return, this saves
351 * us from cowing blocks in the destination tree and doing
352 * extra writes that may not have been done by a previous
353 * sync
354 */
355 if (ret == 0) {
356 btrfs_release_path(root, path);
357 return 0;
358 }
359
360 }
361insert:
362 btrfs_release_path(root, path);
363 /* try to insert the key into the destination tree */
364 ret = btrfs_insert_empty_item(trans, root, path,
365 key, item_size);
366
367 /* make sure any existing item is the correct size */
368 if (ret == -EEXIST) {
369 u32 found_size;
370 found_size = btrfs_item_size_nr(path->nodes[0],
371 path->slots[0]);
372 if (found_size > item_size) {
373 btrfs_truncate_item(trans, root, path, item_size, 1);
374 } else if (found_size < item_size) {
375 ret = btrfs_del_item(trans, root,
376 path);
377 BUG_ON(ret);
378
379 btrfs_release_path(root, path);
380 ret = btrfs_insert_empty_item(trans,
381 root, path, key, item_size);
382 BUG_ON(ret);
383 }
384 } else if (ret) {
385 BUG();
386 }
387 dst_ptr = btrfs_item_ptr_offset(path->nodes[0],
388 path->slots[0]);
389
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.
393 *
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
397 * as it goes
398 */
399 if (key->type == BTRFS_INODE_ITEM_KEY && ret == -EEXIST) {
400 struct btrfs_inode_item *src_item;
401 struct btrfs_inode_item *dst_item;
402
403 src_item = (struct btrfs_inode_item *)src_ptr;
404 dst_item = (struct btrfs_inode_item *)dst_ptr;
405
406 if (btrfs_inode_generation(eb, src_item) == 0)
407 goto no_copy;
408
409 if (overwrite_root &&
410 S_ISDIR(btrfs_inode_mode(eb, src_item)) &&
411 S_ISDIR(btrfs_inode_mode(path->nodes[0], dst_item))) {
412 save_old_i_size = 1;
413 saved_i_size = btrfs_inode_size(path->nodes[0],
414 dst_item);
415 }
416 }
417
418 copy_extent_buffer(path->nodes[0], eb, dst_ptr,
419 src_ptr, item_size);
420
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);
425 }
426
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,
433 trans->transid);
434 }
435 }
436
437 if (overwrite_root &&
438 key->type == BTRFS_EXTENT_DATA_KEY) {
439 int extent_type;
440 struct btrfs_file_extent_item *fi;
441
442 fi = (struct btrfs_file_extent_item *)dst_ptr;
443 extent_type = btrfs_file_extent_type(path->nodes[0], fi);
444 if (extent_type == BTRFS_FILE_EXTENT_REG) {
445 struct btrfs_key ins;
446 ins.objectid = btrfs_file_extent_disk_bytenr(
447 path->nodes[0], fi);
448 ins.offset = btrfs_file_extent_disk_num_bytes(
449 path->nodes[0], fi);
450 ins.type = BTRFS_EXTENT_ITEM_KEY;
451
452 /*
453 * is this extent already allocated in the extent
454 * allocation tree? If so, just add a reference
455 */
456 ret = btrfs_lookup_extent(root, ins.objectid,
457 ins.offset);
458 if (ret == 0) {
459 ret = btrfs_inc_extent_ref(trans, root,
460 ins.objectid, ins.offset,
461 path->nodes[0]->start,
462 root->root_key.objectid,
463 trans->transid,
464 key->objectid, key->offset);
465 } else {
466 /*
467 * insert the extent pointer in the extent
468 * allocation tree
469 */
470 ret = btrfs_alloc_logged_extent(trans, root,
471 path->nodes[0]->start,
472 root->root_key.objectid,
473 trans->transid, key->objectid,
474 key->offset, &ins);
475 BUG_ON(ret);
476 }
477 }
478 }
479no_copy:
480 btrfs_mark_buffer_dirty(path->nodes[0]);
481 btrfs_release_path(root, path);
482 return 0;
483}
484
485/*
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
488 */
489static noinline struct inode *read_one_inode(struct btrfs_root *root,
490 u64 objectid)
491{
492 struct inode *inode;
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);
501
502 }
503 if (is_bad_inode(inode)) {
504 iput(inode);
505 inode = NULL;
506 }
507 return inode;
508}
509
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
512 * on exit.
513 *
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.
518 *
519 * The extent is inserted into the file, dropping any existing extents
520 * from the file that overlap the new one.
521 */
522static 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)
527{
528 int found_type;
529 u64 mask = root->sectorsize - 1;
530 u64 extent_end;
531 u64 alloc_hint;
532 u64 start = key->offset;
533 struct btrfs_file_extent_item *item;
534 struct inode *inode = NULL;
535 unsigned long size;
536 int ret = 0;
537
538 item = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
539 found_type = btrfs_file_extent_type(eb, item);
540
541 if (found_type == BTRFS_FILE_EXTENT_REG)
542 extent_end = start + btrfs_file_extent_num_bytes(eb, item);
543 else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
544 size = btrfs_file_extent_inline_len(eb,
545 btrfs_item_nr(eb, slot));
546 extent_end = (start + size + mask) & ~mask;
547 } else {
548 ret = 0;
549 goto out;
550 }
551
552 inode = read_one_inode(root, key->objectid);
553 if (!inode) {
554 ret = -EIO;
555 goto out;
556 }
557
558 /*
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.
562 */
563 ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino,
564 start, 0);
565
566 if (ret == 0 && found_type == BTRFS_FILE_EXTENT_REG) {
567 struct btrfs_file_extent_item cmp1;
568 struct btrfs_file_extent_item cmp2;
569 struct btrfs_file_extent_item *existing;
570 struct extent_buffer *leaf;
571
572 leaf = path->nodes[0];
573 existing = btrfs_item_ptr(leaf, path->slots[0],
574 struct btrfs_file_extent_item);
575
576 read_extent_buffer(eb, &cmp1, (unsigned long)item,
577 sizeof(cmp1));
578 read_extent_buffer(leaf, &cmp2, (unsigned long)existing,
579 sizeof(cmp2));
580
581 /*
582 * we already have a pointer to this exact extent,
583 * we don't have to do anything
584 */
585 if (memcmp(&cmp1, &cmp2, sizeof(cmp1)) == 0) {
586 btrfs_release_path(root, path);
587 goto out;
588 }
589 }
590 btrfs_release_path(root, path);
591
592 /* drop any overlapping extents */
593 ret = btrfs_drop_extents(trans, root, inode,
594 start, extent_end, start, &alloc_hint);
595 BUG_ON(ret);
596
597 /* insert the extent */
598 ret = overwrite_item(trans, root, path, eb, slot, key);
599 BUG_ON(ret);
600
601 /* btrfs_drop_extents changes i_blocks, update it here */
602 inode->i_blocks += (extent_end - start) >> 9;
603 btrfs_update_inode(trans, root, inode);
604out:
605 if (inode)
606 iput(inode);
607 return ret;
608}
609
610/*
611 * when cleaning up conflicts between the directory names in the
612 * subvolume, directory names in the log and directory names in the
613 * inode back references, we may have to unlink inodes from directories.
614 *
615 * This is a helper function to do the unlink of a specific directory
616 * item
617 */
618static noinline int drop_one_dir_item(struct btrfs_trans_handle *trans,
619 struct btrfs_root *root,
620 struct btrfs_path *path,
621 struct inode *dir,
622 struct btrfs_dir_item *di)
623{
624 struct inode *inode;
625 char *name;
626 int name_len;
627 struct extent_buffer *leaf;
628 struct btrfs_key location;
629 int ret;
630
631 leaf = path->nodes[0];
632
633 btrfs_dir_item_key_to_cpu(leaf, di, &location);
634 name_len = btrfs_dir_name_len(leaf, di);
635 name = kmalloc(name_len, GFP_NOFS);
636 read_extent_buffer(leaf, name, (unsigned long)(di + 1), name_len);
637 btrfs_release_path(root, path);
638
639 inode = read_one_inode(root, location.objectid);
640 BUG_ON(!inode);
641
642 btrfs_inc_nlink(inode);
643 ret = btrfs_unlink_inode(trans, root, dir, inode, name, name_len);
644 kfree(name);
645
646 iput(inode);
647 return ret;
648}
649
650/*
651 * helper function to see if a given name and sequence number found
652 * in an inode back reference are already in a directory and correctly
653 * point to this inode
654 */
655static noinline int inode_in_dir(struct btrfs_root *root,
656 struct btrfs_path *path,
657 u64 dirid, u64 objectid, u64 index,
658 const char *name, int name_len)
659{
660 struct btrfs_dir_item *di;
661 struct btrfs_key location;
662 int match = 0;
663
664 di = btrfs_lookup_dir_index_item(NULL, root, path, dirid,
665 index, name, name_len, 0);
666 if (di && !IS_ERR(di)) {
667 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location);
668 if (location.objectid != objectid)
669 goto out;
670 } else
671 goto out;
672 btrfs_release_path(root, path);
673
674 di = btrfs_lookup_dir_item(NULL, root, path, dirid, name, name_len, 0);
675 if (di && !IS_ERR(di)) {
676 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location);
677 if (location.objectid != objectid)
678 goto out;
679 } else
680 goto out;
681 match = 1;
682out:
683 btrfs_release_path(root, path);
684 return match;
685}
686
687/*
688 * helper function to check a log tree for a named back reference in
689 * an inode. This is used to decide if a back reference that is
690 * found in the subvolume conflicts with what we find in the log.
691 *
692 * inode backreferences may have multiple refs in a single item,
693 * during replay we process one reference at a time, and we don't
694 * want to delete valid links to a file from the subvolume if that
695 * link is also in the log.
696 */
697static noinline int backref_in_log(struct btrfs_root *log,
698 struct btrfs_key *key,
699 char *name, int namelen)
700{
701 struct btrfs_path *path;
702 struct btrfs_inode_ref *ref;
703 unsigned long ptr;
704 unsigned long ptr_end;
705 unsigned long name_ptr;
706 int found_name_len;
707 int item_size;
708 int ret;
709 int match = 0;
710
711 path = btrfs_alloc_path();
712 ret = btrfs_search_slot(NULL, log, key, path, 0, 0);
713 if (ret != 0)
714 goto out;
715
716 item_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]);
717 ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
718 ptr_end = ptr + item_size;
719 while (ptr < ptr_end) {
720 ref = (struct btrfs_inode_ref *)ptr;
721 found_name_len = btrfs_inode_ref_name_len(path->nodes[0], ref);
722 if (found_name_len == namelen) {
723 name_ptr = (unsigned long)(ref + 1);
724 ret = memcmp_extent_buffer(path->nodes[0], name,
725 name_ptr, namelen);
726 if (ret == 0) {
727 match = 1;
728 goto out;
729 }
730 }
731 ptr = (unsigned long)(ref + 1) + found_name_len;
732 }
733out:
734 btrfs_free_path(path);
735 return match;
736}
737
738
739/*
740 * replay one inode back reference item found in the log tree.
741 * eb, slot and key refer to the buffer and key found in the log tree.
742 * root is the destination we are replaying into, and path is for temp
743 * use by this function. (it should be released on return).
744 */
745static noinline int add_inode_ref(struct btrfs_trans_handle *trans,
746 struct btrfs_root *root,
747 struct btrfs_root *log,
748 struct btrfs_path *path,
749 struct extent_buffer *eb, int slot,
750 struct btrfs_key *key)
751{
752 struct inode *dir;
753 int ret;
754 struct btrfs_key location;
755 struct btrfs_inode_ref *ref;
756 struct btrfs_dir_item *di;
757 struct inode *inode;
758 char *name;
759 int namelen;
760 unsigned long ref_ptr;
761 unsigned long ref_end;
762
763 location.objectid = key->objectid;
764 location.type = BTRFS_INODE_ITEM_KEY;
765 location.offset = 0;
766
767 /*
768 * it is possible that we didn't log all the parent directories
769 * for a given inode. If we don't find the dir, just don't
770 * copy the back ref in. The link count fixup code will take
771 * care of the rest
772 */
773 dir = read_one_inode(root, key->offset);
774 if (!dir)
775 return -ENOENT;
776
777 inode = read_one_inode(root, key->objectid);
778 BUG_ON(!dir);
779
780 ref_ptr = btrfs_item_ptr_offset(eb, slot);
781 ref_end = ref_ptr + btrfs_item_size_nr(eb, slot);
782
783again:
784 ref = (struct btrfs_inode_ref *)ref_ptr;
785
786 namelen = btrfs_inode_ref_name_len(eb, ref);
787 name = kmalloc(namelen, GFP_NOFS);
788 BUG_ON(!name);
789
790 read_extent_buffer(eb, name, (unsigned long)(ref + 1), namelen);
791
792 /* if we already have a perfect match, we're done */
793 if (inode_in_dir(root, path, dir->i_ino, inode->i_ino,
794 btrfs_inode_ref_index(eb, ref),
795 name, namelen)) {
796 goto out;
797 }
798
799 /*
800 * look for a conflicting back reference in the metadata.
801 * if we find one we have to unlink that name of the file
802 * before we add our new link. Later on, we overwrite any
803 * existing back reference, and we don't want to create
804 * dangling pointers in the directory.
805 */
806conflict_again:
807 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
808 if (ret == 0) {
809 char *victim_name;
810 int victim_name_len;
811 struct btrfs_inode_ref *victim_ref;
812 unsigned long ptr;
813 unsigned long ptr_end;
814 struct extent_buffer *leaf = path->nodes[0];
815
816 /* are we trying to overwrite a back ref for the root directory
817 * if so, just jump out, we're done
818 */
819 if (key->objectid == key->offset)
820 goto out_nowrite;
821
822 /* check all the names in this back reference to see
823 * if they are in the log. if so, we allow them to stay
824 * otherwise they must be unlinked as a conflict
825 */
826 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
827 ptr_end = ptr + btrfs_item_size_nr(leaf, path->slots[0]);
828 while(ptr < ptr_end) {
829 victim_ref = (struct btrfs_inode_ref *)ptr;
830 victim_name_len = btrfs_inode_ref_name_len(leaf,
831 victim_ref);
832 victim_name = kmalloc(victim_name_len, GFP_NOFS);
833 BUG_ON(!victim_name);
834
835 read_extent_buffer(leaf, victim_name,
836 (unsigned long)(victim_ref + 1),
837 victim_name_len);
838
839 if (!backref_in_log(log, key, victim_name,
840 victim_name_len)) {
841 btrfs_inc_nlink(inode);
842 btrfs_release_path(root, path);
843 ret = btrfs_unlink_inode(trans, root, dir,
844 inode, victim_name,
845 victim_name_len);
846 kfree(victim_name);
847 btrfs_release_path(root, path);
848 goto conflict_again;
849 }
850 kfree(victim_name);
851 ptr = (unsigned long)(victim_ref + 1) + victim_name_len;
852 }
853 BUG_ON(ret);
854 }
855 btrfs_release_path(root, path);
856
857 /* look for a conflicting sequence number */
858 di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
859 btrfs_inode_ref_index(eb, ref),
860 name, namelen, 0);
861 if (di && !IS_ERR(di)) {
862 ret = drop_one_dir_item(trans, root, path, dir, di);
863 BUG_ON(ret);
864 }
865 btrfs_release_path(root, path);
866
867
868 /* look for a conflicting name */
869 di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
870 name, namelen, 0);
871 if (di && !IS_ERR(di)) {
872 ret = drop_one_dir_item(trans, root, path, dir, di);
873 BUG_ON(ret);
874 }
875 btrfs_release_path(root, path);
876
877 /* insert our name */
878 ret = btrfs_add_link(trans, dir, inode, name, namelen, 0,
879 btrfs_inode_ref_index(eb, ref));
880 BUG_ON(ret);
881
882 btrfs_update_inode(trans, root, inode);
883
884out:
885 ref_ptr = (unsigned long)(ref + 1) + namelen;
886 kfree(name);
887 if (ref_ptr < ref_end)
888 goto again;
889
890 /* finally write the back reference in the inode */
891 ret = overwrite_item(trans, root, path, eb, slot, key);
892 BUG_ON(ret);
893
894out_nowrite:
895 btrfs_release_path(root, path);
896 iput(dir);
897 iput(inode);
898 return 0;
899}
900
901/*
902 * replay one csum item from the log tree into the subvolume 'root'
903 * eb, slot and key all refer to the log tree
904 * path is for temp use by this function and should be released on return
905 *
906 * This copies the checksums out of the log tree and inserts them into
907 * the subvolume. Any existing checksums for this range in the file
908 * are overwritten, and new items are added where required.
909 *
910 * We keep this simple by reusing the btrfs_ordered_sum code from
911 * the data=ordered mode. This basically means making a copy
912 * of all the checksums in ram, which we have to do anyway for kmap
913 * rules.
914 *
915 * The copy is then sent down to btrfs_csum_file_blocks, which
916 * does all the hard work of finding existing items in the file
917 * or adding new ones.
918 */
919static noinline int replay_one_csum(struct btrfs_trans_handle *trans,
920 struct btrfs_root *root,
921 struct btrfs_path *path,
922 struct extent_buffer *eb, int slot,
923 struct btrfs_key *key)
924{
925 int ret;
926 u32 item_size = btrfs_item_size_nr(eb, slot);
927 u64 cur_offset;
928 unsigned long file_bytes;
929 struct btrfs_ordered_sum *sums;
930 struct btrfs_sector_sum *sector_sum;
931 struct inode *inode;
932 unsigned long ptr;
933
934 file_bytes = (item_size / BTRFS_CRC32_SIZE) * root->sectorsize;
935 inode = read_one_inode(root, key->objectid);
936 if (!inode) {
937 return -EIO;
938 }
939
940 sums = kzalloc(btrfs_ordered_sum_size(root, file_bytes), GFP_NOFS);
941 if (!sums) {
942 iput(inode);
943 return -ENOMEM;
944 }
945
946 INIT_LIST_HEAD(&sums->list);
947 sums->len = file_bytes;
948 sums->file_offset = key->offset;
949
950 /*
951 * copy all the sums into the ordered sum struct
952 */
953 sector_sum = sums->sums;
954 cur_offset = key->offset;
955 ptr = btrfs_item_ptr_offset(eb, slot);
956 while(item_size > 0) {
957 sector_sum->offset = cur_offset;
958 read_extent_buffer(eb, &sector_sum->sum, ptr, BTRFS_CRC32_SIZE);
959 sector_sum++;
960 item_size -= BTRFS_CRC32_SIZE;
961 ptr += BTRFS_CRC32_SIZE;
962 cur_offset += root->sectorsize;
963 }
964
965 /* let btrfs_csum_file_blocks add them into the file */
966 ret = btrfs_csum_file_blocks(trans, root, inode, sums);
967 BUG_ON(ret);
968 kfree(sums);
969 iput(inode);
970
971 return 0;
972}
973/*
974 * There are a few corners where the link count of the file can't
975 * be properly maintained during replay. So, instead of adding
976 * lots of complexity to the log code, we just scan the backrefs
977 * for any file that has been through replay.
978 *
979 * The scan will update the link count on the inode to reflect the
980 * number of back refs found. If it goes down to zero, the iput
981 * will free the inode.
982 */
983static noinline int fixup_inode_link_count(struct btrfs_trans_handle *trans,
984 struct btrfs_root *root,
985 struct inode *inode)
986{
987 struct btrfs_path *path;
988 int ret;
989 struct btrfs_key key;
990 u64 nlink = 0;
991 unsigned long ptr;
992 unsigned long ptr_end;
993 int name_len;
994
995 key.objectid = inode->i_ino;
996 key.type = BTRFS_INODE_REF_KEY;
997 key.offset = (u64)-1;
998
999 path = btrfs_alloc_path();
1000
1001 while(1) {
1002 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1003 if (ret < 0)
1004 break;
1005 if (ret > 0) {
1006 if (path->slots[0] == 0)
1007 break;
1008 path->slots[0]--;
1009 }
1010 btrfs_item_key_to_cpu(path->nodes[0], &key,
1011 path->slots[0]);
1012 if (key.objectid != inode->i_ino ||
1013 key.type != BTRFS_INODE_REF_KEY)
1014 break;
1015 ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
1016 ptr_end = ptr + btrfs_item_size_nr(path->nodes[0],
1017 path->slots[0]);
1018 while(ptr < ptr_end) {
1019 struct btrfs_inode_ref *ref;
1020
1021 ref = (struct btrfs_inode_ref *)ptr;
1022 name_len = btrfs_inode_ref_name_len(path->nodes[0],
1023 ref);
1024 ptr = (unsigned long)(ref + 1) + name_len;
1025 nlink++;
1026 }
1027
1028 if (key.offset == 0)
1029 break;
1030 key.offset--;
1031 btrfs_release_path(root, path);
1032 }
1033 btrfs_free_path(path);
1034 if (nlink != inode->i_nlink) {
1035 inode->i_nlink = nlink;
1036 btrfs_update_inode(trans, root, inode);
1037 }
1038 BTRFS_I(inode)->index_cnt = (u64)-1;
1039
1040 return 0;
1041}
1042
1043static noinline int fixup_inode_link_counts(struct btrfs_trans_handle *trans,
1044 struct btrfs_root *root,
1045 struct btrfs_path *path)
1046{
1047 int ret;
1048 struct btrfs_key key;
1049 struct inode *inode;
1050
1051 key.objectid = BTRFS_TREE_LOG_FIXUP_OBJECTID;
1052 key.type = BTRFS_ORPHAN_ITEM_KEY;
1053 key.offset = (u64)-1;
1054 while(1) {
1055 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1056 if (ret < 0)
1057 break;
1058
1059 if (ret == 1) {
1060 if (path->slots[0] == 0)
1061 break;
1062 path->slots[0]--;
1063 }
1064
1065 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1066 if (key.objectid != BTRFS_TREE_LOG_FIXUP_OBJECTID ||
1067 key.type != BTRFS_ORPHAN_ITEM_KEY)
1068 break;
1069
1070 ret = btrfs_del_item(trans, root, path);
1071 BUG_ON(ret);
1072
1073 btrfs_release_path(root, path);
1074 inode = read_one_inode(root, key.offset);
1075 BUG_ON(!inode);
1076
1077 ret = fixup_inode_link_count(trans, root, inode);
1078 BUG_ON(ret);
1079
1080 iput(inode);
1081
1082 if (key.offset == 0)
1083 break;
1084 key.offset--;
1085 }
1086 btrfs_release_path(root, path);
1087 return 0;
1088}
1089
1090
1091/*
1092 * record a given inode in the fixup dir so we can check its link
1093 * count when replay is done. The link count is incremented here
1094 * so the inode won't go away until we check it
1095 */
1096static noinline int link_to_fixup_dir(struct btrfs_trans_handle *trans,
1097 struct btrfs_root *root,
1098 struct btrfs_path *path,
1099 u64 objectid)
1100{
1101 struct btrfs_key key;
1102 int ret = 0;
1103 struct inode *inode;
1104
1105 inode = read_one_inode(root, objectid);
1106 BUG_ON(!inode);
1107
1108 key.objectid = BTRFS_TREE_LOG_FIXUP_OBJECTID;
1109 btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
1110 key.offset = objectid;
1111
1112 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1113
1114 btrfs_release_path(root, path);
1115 if (ret == 0) {
1116 btrfs_inc_nlink(inode);
1117 btrfs_update_inode(trans, root, inode);
1118 } else if (ret == -EEXIST) {
1119 ret = 0;
1120 } else {
1121 BUG();
1122 }
1123 iput(inode);
1124
1125 return ret;
1126}
1127
1128/*
1129 * when replaying the log for a directory, we only insert names
1130 * for inodes that actually exist. This means an fsync on a directory
1131 * does not implicitly fsync all the new files in it
1132 */
1133static noinline int insert_one_name(struct btrfs_trans_handle *trans,
1134 struct btrfs_root *root,
1135 struct btrfs_path *path,
1136 u64 dirid, u64 index,
1137 char *name, int name_len, u8 type,
1138 struct btrfs_key *location)
1139{
1140 struct inode *inode;
1141 struct inode *dir;
1142 int ret;
1143
1144 inode = read_one_inode(root, location->objectid);
1145 if (!inode)
1146 return -ENOENT;
1147
1148 dir = read_one_inode(root, dirid);
1149 if (!dir) {
1150 iput(inode);
1151 return -EIO;
1152 }
1153 ret = btrfs_add_link(trans, dir, inode, name, name_len, 1, index);
1154
1155 /* FIXME, put inode into FIXUP list */
1156
1157 iput(inode);
1158 iput(dir);
1159 return ret;
1160}
1161
1162/*
1163 * take a single entry in a log directory item and replay it into
1164 * the subvolume.
1165 *
1166 * if a conflicting item exists in the subdirectory already,
1167 * the inode it points to is unlinked and put into the link count
1168 * fix up tree.
1169 *
1170 * If a name from the log points to a file or directory that does
1171 * not exist in the FS, it is skipped. fsyncs on directories
1172 * do not force down inodes inside that directory, just changes to the
1173 * names or unlinks in a directory.
1174 */
1175static noinline int replay_one_name(struct btrfs_trans_handle *trans,
1176 struct btrfs_root *root,
1177 struct btrfs_path *path,
1178 struct extent_buffer *eb,
1179 struct btrfs_dir_item *di,
1180 struct btrfs_key *key)
1181{
1182 char *name;
1183 int name_len;
1184 struct btrfs_dir_item *dst_di;
1185 struct btrfs_key found_key;
1186 struct btrfs_key log_key;
1187 struct inode *dir;
1188 u8 log_type;
1189 int exists;
1190 int ret;
1191
1192 dir = read_one_inode(root, key->objectid);
1193 BUG_ON(!dir);
1194
1195 name_len = btrfs_dir_name_len(eb, di);
1196 name = kmalloc(name_len, GFP_NOFS);
1197 log_type = btrfs_dir_type(eb, di);
1198 read_extent_buffer(eb, name, (unsigned long)(di + 1),
1199 name_len);
1200
1201 btrfs_dir_item_key_to_cpu(eb, di, &log_key);
1202 exists = btrfs_lookup_inode(trans, root, path, &log_key, 0);
1203 if (exists == 0)
1204 exists = 1;
1205 else
1206 exists = 0;
1207 btrfs_release_path(root, path);
1208
1209 if (key->type == BTRFS_DIR_ITEM_KEY) {
1210 dst_di = btrfs_lookup_dir_item(trans, root, path, key->objectid,
1211 name, name_len, 1);
1212 }
1213 else if (key->type == BTRFS_DIR_INDEX_KEY) {
1214 dst_di = btrfs_lookup_dir_index_item(trans, root, path,
1215 key->objectid,
1216 key->offset, name,
1217 name_len, 1);
1218 } else {
1219 BUG();
1220 }
1221 if (!dst_di || IS_ERR(dst_di)) {
1222 /* we need a sequence number to insert, so we only
1223 * do inserts for the BTRFS_DIR_INDEX_KEY types
1224 */
1225 if (key->type != BTRFS_DIR_INDEX_KEY)
1226 goto out;
1227 goto insert;
1228 }
1229
1230 btrfs_dir_item_key_to_cpu(path->nodes[0], dst_di, &found_key);
1231 /* the existing item matches the logged item */
1232 if (found_key.objectid == log_key.objectid &&
1233 found_key.type == log_key.type &&
1234 found_key.offset == log_key.offset &&
1235 btrfs_dir_type(path->nodes[0], dst_di) == log_type) {
1236 goto out;
1237 }
1238
1239 /*
1240 * don't drop the conflicting directory entry if the inode
1241 * for the new entry doesn't exist
1242 */
1243 if (!exists)
1244 goto out;
1245
1246 ret = drop_one_dir_item(trans, root, path, dir, dst_di);
1247 BUG_ON(ret);
1248
1249 if (key->type == BTRFS_DIR_INDEX_KEY)
1250 goto insert;
1251out:
1252 btrfs_release_path(root, path);
1253 kfree(name);
1254 iput(dir);
1255 return 0;
1256
1257insert:
1258 btrfs_release_path(root, path);
1259 ret = insert_one_name(trans, root, path, key->objectid, key->offset,
1260 name, name_len, log_type, &log_key);
1261
1262 if (ret && ret != -ENOENT)
1263 BUG();
1264 goto out;
1265}
1266
1267/*
1268 * find all the names in a directory item and reconcile them into
1269 * the subvolume. Only BTRFS_DIR_ITEM_KEY types will have more than
1270 * one name in a directory item, but the same code gets used for
1271 * both directory index types
1272 */
1273static noinline int replay_one_dir_item(struct btrfs_trans_handle *trans,
1274 struct btrfs_root *root,
1275 struct btrfs_path *path,
1276 struct extent_buffer *eb, int slot,
1277 struct btrfs_key *key)
1278{
1279 int ret;
1280 u32 item_size = btrfs_item_size_nr(eb, slot);
1281 struct btrfs_dir_item *di;
1282 int name_len;
1283 unsigned long ptr;
1284 unsigned long ptr_end;
1285
1286 ptr = btrfs_item_ptr_offset(eb, slot);
1287 ptr_end = ptr + item_size;
1288 while(ptr < ptr_end) {
1289 di = (struct btrfs_dir_item *)ptr;
1290 name_len = btrfs_dir_name_len(eb, di);
1291 ret = replay_one_name(trans, root, path, eb, di, key);
1292 BUG_ON(ret);
1293 ptr = (unsigned long)(di + 1);
1294 ptr += name_len;
1295 }
1296 return 0;
1297}
1298
1299/*
1300 * directory replay has two parts. There are the standard directory
1301 * items in the log copied from the subvolume, and range items
1302 * created in the log while the subvolume was logged.
1303 *
1304 * The range items tell us which parts of the key space the log
1305 * is authoritative for. During replay, if a key in the subvolume
1306 * directory is in a logged range item, but not actually in the log
1307 * that means it was deleted from the directory before the fsync
1308 * and should be removed.
1309 */
1310static noinline int find_dir_range(struct btrfs_root *root,
1311 struct btrfs_path *path,
1312 u64 dirid, int key_type,
1313 u64 *start_ret, u64 *end_ret)
1314{
1315 struct btrfs_key key;
1316 u64 found_end;
1317 struct btrfs_dir_log_item *item;
1318 int ret;
1319 int nritems;
1320
1321 if (*start_ret == (u64)-1)
1322 return 1;
1323
1324 key.objectid = dirid;
1325 key.type = key_type;
1326 key.offset = *start_ret;
1327
1328 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1329 if (ret < 0)
1330 goto out;
1331 if (ret > 0) {
1332 if (path->slots[0] == 0)
1333 goto out;
1334 path->slots[0]--;
1335 }
1336 if (ret != 0)
1337 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1338
1339 if (key.type != key_type || key.objectid != dirid) {
1340 ret = 1;
1341 goto next;
1342 }
1343 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
1344 struct btrfs_dir_log_item);
1345 found_end = btrfs_dir_log_end(path->nodes[0], item);
1346
1347 if (*start_ret >= key.offset && *start_ret <= found_end) {
1348 ret = 0;
1349 *start_ret = key.offset;
1350 *end_ret = found_end;
1351 goto out;
1352 }
1353 ret = 1;
1354next:
1355 /* check the next slot in the tree to see if it is a valid item */
1356 nritems = btrfs_header_nritems(path->nodes[0]);
1357 if (path->slots[0] >= nritems) {
1358 ret = btrfs_next_leaf(root, path);
1359 if (ret)
1360 goto out;
1361 } else {
1362 path->slots[0]++;
1363 }
1364
1365 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1366
1367 if (key.type != key_type || key.objectid != dirid) {
1368 ret = 1;
1369 goto out;
1370 }
1371 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
1372 struct btrfs_dir_log_item);
1373 found_end = btrfs_dir_log_end(path->nodes[0], item);
1374 *start_ret = key.offset;
1375 *end_ret = found_end;
1376 ret = 0;
1377out:
1378 btrfs_release_path(root, path);
1379 return ret;
1380}
1381
1382/*
1383 * this looks for a given directory item in the log. If the directory
1384 * item is not in the log, the item is removed and the inode it points
1385 * to is unlinked
1386 */
1387static noinline int check_item_in_log(struct btrfs_trans_handle *trans,
1388 struct btrfs_root *root,
1389 struct btrfs_root *log,
1390 struct btrfs_path *path,
1391 struct btrfs_path *log_path,
1392 struct inode *dir,
1393 struct btrfs_key *dir_key)
1394{
1395 int ret;
1396 struct extent_buffer *eb;
1397 int slot;
1398 u32 item_size;
1399 struct btrfs_dir_item *di;
1400 struct btrfs_dir_item *log_di;
1401 int name_len;
1402 unsigned long ptr;
1403 unsigned long ptr_end;
1404 char *name;
1405 struct inode *inode;
1406 struct btrfs_key location;
1407
1408again:
1409 eb = path->nodes[0];
1410 slot = path->slots[0];
1411 item_size = btrfs_item_size_nr(eb, slot);
1412 ptr = btrfs_item_ptr_offset(eb, slot);
1413 ptr_end = ptr + item_size;
1414 while(ptr < ptr_end) {
1415 di = (struct btrfs_dir_item *)ptr;
1416 name_len = btrfs_dir_name_len(eb, di);
1417 name = kmalloc(name_len, GFP_NOFS);
1418 if (!name) {
1419 ret = -ENOMEM;
1420 goto out;
1421 }
1422 read_extent_buffer(eb, name, (unsigned long)(di + 1),
1423 name_len);
1424 log_di = NULL;
1425 if (dir_key->type == BTRFS_DIR_ITEM_KEY) {
1426 log_di = btrfs_lookup_dir_item(trans, log, log_path,
1427 dir_key->objectid,
1428 name, name_len, 0);
1429 } else if (dir_key->type == BTRFS_DIR_INDEX_KEY) {
1430 log_di = btrfs_lookup_dir_index_item(trans, log,
1431 log_path,
1432 dir_key->objectid,
1433 dir_key->offset,
1434 name, name_len, 0);
1435 }
1436 if (!log_di || IS_ERR(log_di)) {
1437 btrfs_dir_item_key_to_cpu(eb, di, &location);
1438 btrfs_release_path(root, path);
1439 btrfs_release_path(log, log_path);
1440 inode = read_one_inode(root, location.objectid);
1441 BUG_ON(!inode);
1442
1443 ret = link_to_fixup_dir(trans, root,
1444 path, location.objectid);
1445 BUG_ON(ret);
1446 btrfs_inc_nlink(inode);
1447 ret = btrfs_unlink_inode(trans, root, dir, inode,
1448 name, name_len);
1449 BUG_ON(ret);
1450 kfree(name);
1451 iput(inode);
1452
1453 /* there might still be more names under this key
1454 * check and repeat if required
1455 */
1456 ret = btrfs_search_slot(NULL, root, dir_key, path,
1457 0, 0);
1458 if (ret == 0)
1459 goto again;
1460 ret = 0;
1461 goto out;
1462 }
1463 btrfs_release_path(log, log_path);
1464 kfree(name);
1465
1466 ptr = (unsigned long)(di + 1);
1467 ptr += name_len;
1468 }
1469 ret = 0;
1470out:
1471 btrfs_release_path(root, path);
1472 btrfs_release_path(log, log_path);
1473 return ret;
1474}
1475
1476/*
1477 * deletion replay happens before we copy any new directory items
1478 * out of the log or out of backreferences from inodes. It
1479 * scans the log to find ranges of keys that log is authoritative for,
1480 * and then scans the directory to find items in those ranges that are
1481 * not present in the log.
1482 *
1483 * Anything we don't find in the log is unlinked and removed from the
1484 * directory.
1485 */
1486static noinline int replay_dir_deletes(struct btrfs_trans_handle *trans,
1487 struct btrfs_root *root,
1488 struct btrfs_root *log,
1489 struct btrfs_path *path,
1490 u64 dirid)
1491{
1492 u64 range_start;
1493 u64 range_end;
1494 int key_type = BTRFS_DIR_LOG_ITEM_KEY;
1495 int ret = 0;
1496 struct btrfs_key dir_key;
1497 struct btrfs_key found_key;
1498 struct btrfs_path *log_path;
1499 struct inode *dir;
1500
1501 dir_key.objectid = dirid;
1502 dir_key.type = BTRFS_DIR_ITEM_KEY;
1503 log_path = btrfs_alloc_path();
1504 if (!log_path)
1505 return -ENOMEM;
1506
1507 dir = read_one_inode(root, dirid);
1508 /* it isn't an error if the inode isn't there, that can happen
1509 * because we replay the deletes before we copy in the inode item
1510 * from the log
1511 */
1512 if (!dir) {
1513 btrfs_free_path(log_path);
1514 return 0;
1515 }
1516again:
1517 range_start = 0;
1518 range_end = 0;
1519 while(1) {
1520 ret = find_dir_range(log, path, dirid, key_type,
1521 &range_start, &range_end);
1522 if (ret != 0)
1523 break;
1524
1525 dir_key.offset = range_start;
1526 while(1) {
1527 int nritems;
1528 ret = btrfs_search_slot(NULL, root, &dir_key, path,
1529 0, 0);
1530 if (ret < 0)
1531 goto out;
1532
1533 nritems = btrfs_header_nritems(path->nodes[0]);
1534 if (path->slots[0] >= nritems) {
1535 ret = btrfs_next_leaf(root, path);
1536 if (ret)
1537 break;
1538 }
1539 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1540 path->slots[0]);
1541 if (found_key.objectid != dirid ||
1542 found_key.type != dir_key.type)
1543 goto next_type;
1544
1545 if (found_key.offset > range_end)
1546 break;
1547
1548 ret = check_item_in_log(trans, root, log, path,
1549 log_path, dir, &found_key);
1550 BUG_ON(ret);
1551 if (found_key.offset == (u64)-1)
1552 break;
1553 dir_key.offset = found_key.offset + 1;
1554 }
1555 btrfs_release_path(root, path);
1556 if (range_end == (u64)-1)
1557 break;
1558 range_start = range_end + 1;
1559 }
1560
1561next_type:
1562 ret = 0;
1563 if (key_type == BTRFS_DIR_LOG_ITEM_KEY) {
1564 key_type = BTRFS_DIR_LOG_INDEX_KEY;
1565 dir_key.type = BTRFS_DIR_INDEX_KEY;
1566 btrfs_release_path(root, path);
1567 goto again;
1568 }
1569out:
1570 btrfs_release_path(root, path);
1571 btrfs_free_path(log_path);
1572 iput(dir);
1573 return ret;
1574}
1575
1576/*
1577 * the process_func used to replay items from the log tree. This
1578 * gets called in two different stages. The first stage just looks
1579 * for inodes and makes sure they are all copied into the subvolume.
1580 *
1581 * The second stage copies all the other item types from the log into
1582 * the subvolume. The two stage approach is slower, but gets rid of
1583 * lots of complexity around inodes referencing other inodes that exist
1584 * only in the log (references come from either directory items or inode
1585 * back refs).
1586 */
1587static int replay_one_buffer(struct btrfs_root *log, struct extent_buffer *eb,
1588 struct walk_control *wc, u64 gen)
1589{
1590 int nritems;
1591 struct btrfs_path *path;
1592 struct btrfs_root *root = wc->replay_dest;
1593 struct btrfs_key key;
1594 u32 item_size;
1595 int level;
1596 int i;
1597 int ret;
1598
1599 btrfs_read_buffer(eb, gen);
1600
1601 level = btrfs_header_level(eb);
1602
1603 if (level != 0)
1604 return 0;
1605
1606 path = btrfs_alloc_path();
1607 BUG_ON(!path);
1608
1609 nritems = btrfs_header_nritems(eb);
1610 for (i = 0; i < nritems; i++) {
1611 btrfs_item_key_to_cpu(eb, &key, i);
1612 item_size = btrfs_item_size_nr(eb, i);
1613
1614 /* inode keys are done during the first stage */
1615 if (key.type == BTRFS_INODE_ITEM_KEY &&
1616 wc->stage == LOG_WALK_REPLAY_INODES) {
1617 struct inode *inode;
1618 struct btrfs_inode_item *inode_item;
1619 u32 mode;
1620
1621 inode_item = btrfs_item_ptr(eb, i,
1622 struct btrfs_inode_item);
1623 mode = btrfs_inode_mode(eb, inode_item);
1624 if (S_ISDIR(mode)) {
1625 ret = replay_dir_deletes(wc->trans,
1626 root, log, path, key.objectid);
1627 BUG_ON(ret);
1628 }
1629 ret = overwrite_item(wc->trans, root, path,
1630 eb, i, &key);
1631 BUG_ON(ret);
1632
1633 /* for regular files, truncate away
1634 * extents past the new EOF
1635 */
1636 if (S_ISREG(mode)) {
1637 inode = read_one_inode(root,
1638 key.objectid);
1639 BUG_ON(!inode);
1640
1641 ret = btrfs_truncate_inode_items(wc->trans,
1642 root, inode, inode->i_size,
1643 BTRFS_EXTENT_DATA_KEY);
1644 BUG_ON(ret);
1645 iput(inode);
1646 }
1647 ret = link_to_fixup_dir(wc->trans, root,
1648 path, key.objectid);
1649 BUG_ON(ret);
1650 }
1651 if (wc->stage < LOG_WALK_REPLAY_ALL)
1652 continue;
1653
1654 /* these keys are simply copied */
1655 if (key.type == BTRFS_XATTR_ITEM_KEY) {
1656 ret = overwrite_item(wc->trans, root, path,
1657 eb, i, &key);
1658 BUG_ON(ret);
1659 } else if (key.type == BTRFS_INODE_REF_KEY) {
1660 ret = add_inode_ref(wc->trans, root, log, path,
1661 eb, i, &key);
1662 BUG_ON(ret && ret != -ENOENT);
1663 } else if (key.type == BTRFS_EXTENT_DATA_KEY) {
1664 ret = replay_one_extent(wc->trans, root, path,
1665 eb, i, &key);
1666 BUG_ON(ret);
1667 } else if (key.type == BTRFS_CSUM_ITEM_KEY) {
1668 ret = replay_one_csum(wc->trans, root, path,
1669 eb, i, &key);
1670 BUG_ON(ret);
1671 } else if (key.type == BTRFS_DIR_ITEM_KEY ||
1672 key.type == BTRFS_DIR_INDEX_KEY) {
1673 ret = replay_one_dir_item(wc->trans, root, path,
1674 eb, i, &key);
1675 BUG_ON(ret);
1676 }
1677 }
1678 btrfs_free_path(path);
1679 return 0;
1680}
1681
1682static int noinline walk_down_log_tree(struct btrfs_trans_handle *trans,
1683 struct btrfs_root *root,
1684 struct btrfs_path *path, int *level,
1685 struct walk_control *wc)
1686{
1687 u64 root_owner;
1688 u64 root_gen;
1689 u64 bytenr;
1690 u64 ptr_gen;
1691 struct extent_buffer *next;
1692 struct extent_buffer *cur;
1693 struct extent_buffer *parent;
1694 u32 blocksize;
1695 int ret = 0;
1696
1697 WARN_ON(*level < 0);
1698 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1699
1700 while(*level > 0) {
1701 WARN_ON(*level < 0);
1702 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1703 cur = path->nodes[*level];
1704
1705 if (btrfs_header_level(cur) != *level)
1706 WARN_ON(1);
1707
1708 if (path->slots[*level] >=
1709 btrfs_header_nritems(cur))
1710 break;
1711
1712 bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
1713 ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
1714 blocksize = btrfs_level_size(root, *level - 1);
1715
1716 parent = path->nodes[*level];
1717 root_owner = btrfs_header_owner(parent);
1718 root_gen = btrfs_header_generation(parent);
1719
1720 next = btrfs_find_create_tree_block(root, bytenr, blocksize);
1721
1722 wc->process_func(root, next, wc, ptr_gen);
1723
1724 if (*level == 1) {
1725 path->slots[*level]++;
1726 if (wc->free) {
1727 btrfs_read_buffer(next, ptr_gen);
1728
1729 btrfs_tree_lock(next);
1730 clean_tree_block(trans, root, next);
1731 btrfs_wait_tree_block_writeback(next);
1732 btrfs_tree_unlock(next);
1733
1734 ret = btrfs_drop_leaf_ref(trans, root, next);
1735 BUG_ON(ret);
1736
1737 WARN_ON(root_owner !=
1738 BTRFS_TREE_LOG_OBJECTID);
1739 ret = btrfs_free_reserved_extent(root,
1740 bytenr, blocksize);
1741 BUG_ON(ret);
1742 }
1743 free_extent_buffer(next);
1744 continue;
1745 }
1746 btrfs_read_buffer(next, ptr_gen);
1747
1748 WARN_ON(*level <= 0);
1749 if (path->nodes[*level-1])
1750 free_extent_buffer(path->nodes[*level-1]);
1751 path->nodes[*level-1] = next;
1752 *level = btrfs_header_level(next);
1753 path->slots[*level] = 0;
1754 cond_resched();
1755 }
1756 WARN_ON(*level < 0);
1757 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1758
1759 if (path->nodes[*level] == root->node) {
1760 parent = path->nodes[*level];
1761 } else {
1762 parent = path->nodes[*level + 1];
1763 }
1764 bytenr = path->nodes[*level]->start;
1765
1766 blocksize = btrfs_level_size(root, *level);
1767 root_owner = btrfs_header_owner(parent);
1768 root_gen = btrfs_header_generation(parent);
1769
1770 wc->process_func(root, path->nodes[*level], wc,
1771 btrfs_header_generation(path->nodes[*level]));
1772
1773 if (wc->free) {
1774 next = path->nodes[*level];
1775 btrfs_tree_lock(next);
1776 clean_tree_block(trans, root, next);
1777 btrfs_wait_tree_block_writeback(next);
1778 btrfs_tree_unlock(next);
1779
1780 if (*level == 0) {
1781 ret = btrfs_drop_leaf_ref(trans, root, next);
1782 BUG_ON(ret);
1783 }
1784 WARN_ON(root_owner != BTRFS_TREE_LOG_OBJECTID);
1785 ret = btrfs_free_reserved_extent(root, bytenr, blocksize);
1786 BUG_ON(ret);
1787 }
1788 free_extent_buffer(path->nodes[*level]);
1789 path->nodes[*level] = NULL;
1790 *level += 1;
1791
1792 cond_resched();
1793 return 0;
1794}
1795
1796static int noinline walk_up_log_tree(struct btrfs_trans_handle *trans,
1797 struct btrfs_root *root,
1798 struct btrfs_path *path, int *level,
1799 struct walk_control *wc)
1800{
1801 u64 root_owner;
1802 u64 root_gen;
1803 int i;
1804 int slot;
1805 int ret;
1806
1807 for(i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
1808 slot = path->slots[i];
1809 if (slot < btrfs_header_nritems(path->nodes[i]) - 1) {
1810 struct extent_buffer *node;
1811 node = path->nodes[i];
1812 path->slots[i]++;
1813 *level = i;
1814 WARN_ON(*level == 0);
1815 return 0;
1816 } else {
1817 struct extent_buffer *parent;
1818 if (path->nodes[*level] == root->node)
1819 parent = path->nodes[*level];
1820 else
1821 parent = path->nodes[*level + 1];
1822
1823 root_owner = btrfs_header_owner(parent);
1824 root_gen = btrfs_header_generation(parent);
1825 wc->process_func(root, path->nodes[*level], wc,
1826 btrfs_header_generation(path->nodes[*level]));
1827 if (wc->free) {
1828 struct extent_buffer *next;
1829
1830 next = path->nodes[*level];
1831
1832 btrfs_tree_lock(next);
1833 clean_tree_block(trans, root, next);
1834 btrfs_wait_tree_block_writeback(next);
1835 btrfs_tree_unlock(next);
1836
1837 if (*level == 0) {
1838 ret = btrfs_drop_leaf_ref(trans, root,
1839 next);
1840 BUG_ON(ret);
1841 }
1842
1843 WARN_ON(root_owner != BTRFS_TREE_LOG_OBJECTID);
1844 ret = btrfs_free_reserved_extent(root,
1845 path->nodes[*level]->start,
1846 path->nodes[*level]->len);
1847 BUG_ON(ret);
1848 }
1849 free_extent_buffer(path->nodes[*level]);
1850 path->nodes[*level] = NULL;
1851 *level = i + 1;
1852 }
1853 }
1854 return 1;
1855}
1856
1857/*
1858 * drop the reference count on the tree rooted at 'snap'. This traverses
1859 * the tree freeing any blocks that have a ref count of zero after being
1860 * decremented.
1861 */
1862static int walk_log_tree(struct btrfs_trans_handle *trans,
1863 struct btrfs_root *log, struct walk_control *wc)
1864{
1865 int ret = 0;
1866 int wret;
1867 int level;
1868 struct btrfs_path *path;
1869 int i;
1870 int orig_level;
1871
1872 path = btrfs_alloc_path();
1873 BUG_ON(!path);
1874
1875 level = btrfs_header_level(log->node);
1876 orig_level = level;
1877 path->nodes[level] = log->node;
1878 extent_buffer_get(log->node);
1879 path->slots[level] = 0;
1880
1881 while(1) {
1882 wret = walk_down_log_tree(trans, log, path, &level, wc);
1883 if (wret > 0)
1884 break;
1885 if (wret < 0)
1886 ret = wret;
1887
1888 wret = walk_up_log_tree(trans, log, path, &level, wc);
1889 if (wret > 0)
1890 break;
1891 if (wret < 0)
1892 ret = wret;
1893 }
1894
1895 /* was the root node processed? if not, catch it here */
1896 if (path->nodes[orig_level]) {
1897 wc->process_func(log, path->nodes[orig_level], wc,
1898 btrfs_header_generation(path->nodes[orig_level]));
1899 if (wc->free) {
1900 struct extent_buffer *next;
1901
1902 next = path->nodes[orig_level];
1903
1904 btrfs_tree_lock(next);
1905 clean_tree_block(trans, log, next);
1906 btrfs_wait_tree_block_writeback(next);
1907 btrfs_tree_unlock(next);
1908
1909 if (orig_level == 0) {
1910 ret = btrfs_drop_leaf_ref(trans, log,
1911 next);
1912 BUG_ON(ret);
1913 }
1914 WARN_ON(log->root_key.objectid !=
1915 BTRFS_TREE_LOG_OBJECTID);
1916 ret = btrfs_free_reserved_extent(log, next->start,
1917 next->len);
1918 BUG_ON(ret);
1919 }
1920 }
1921
1922 for (i = 0; i <= orig_level; i++) {
1923 if (path->nodes[i]) {
1924 free_extent_buffer(path->nodes[i]);
1925 path->nodes[i] = NULL;
1926 }
1927 }
1928 btrfs_free_path(path);
1929 if (wc->free)
1930 free_extent_buffer(log->node);
1931 return ret;
1932}
1933
1934int wait_log_commit(struct btrfs_root *log)
1935{
1936 DEFINE_WAIT(wait);
1937 u64 transid = log->fs_info->tree_log_transid;
1938
1939 do {
1940 prepare_to_wait(&log->fs_info->tree_log_wait, &wait,
1941 TASK_UNINTERRUPTIBLE);
1942 mutex_unlock(&log->fs_info->tree_log_mutex);
1943 if (atomic_read(&log->fs_info->tree_log_commit))
1944 schedule();
1945 finish_wait(&log->fs_info->tree_log_wait, &wait);
1946 mutex_lock(&log->fs_info->tree_log_mutex);
1947 } while(transid == log->fs_info->tree_log_transid &&
1948 atomic_read(&log->fs_info->tree_log_commit));
1949 return 0;
1950}
1951
1952/*
1953 * btrfs_sync_log does sends a given tree log down to the disk and
1954 * updates the super blocks to record it. When this call is done,
1955 * you know that any inodes previously logged are safely on disk
1956 */
1957int btrfs_sync_log(struct btrfs_trans_handle *trans,
1958 struct btrfs_root *root)
1959{
1960 int ret;
1961 unsigned long batch;
1962 struct btrfs_root *log = root->log_root;
1963
1964 mutex_lock(&log->fs_info->tree_log_mutex);
1965 if (atomic_read(&log->fs_info->tree_log_commit)) {
1966 wait_log_commit(log);
1967 goto out;
1968 }
1969 atomic_set(&log->fs_info->tree_log_commit, 1);
1970
1971 while(1) {
1972 batch = log->fs_info->tree_log_batch;
1973 mutex_unlock(&log->fs_info->tree_log_mutex);
1974 schedule_timeout_uninterruptible(1);
1975 mutex_lock(&log->fs_info->tree_log_mutex);
1976
1977 while(atomic_read(&log->fs_info->tree_log_writers)) {
1978 DEFINE_WAIT(wait);
1979 prepare_to_wait(&log->fs_info->tree_log_wait, &wait,
1980 TASK_UNINTERRUPTIBLE);
1981 mutex_unlock(&log->fs_info->tree_log_mutex);
1982 if (atomic_read(&log->fs_info->tree_log_writers))
1983 schedule();
1984 mutex_lock(&log->fs_info->tree_log_mutex);
1985 finish_wait(&log->fs_info->tree_log_wait, &wait);
1986 }
1987 if (batch == log->fs_info->tree_log_batch)
1988 break;
1989 }
1990
1991 ret = btrfs_write_and_wait_marked_extents(log, &log->dirty_log_pages);
1992 BUG_ON(ret);
1993 ret = btrfs_write_and_wait_marked_extents(root->fs_info->log_root_tree,
1994 &root->fs_info->log_root_tree->dirty_log_pages);
1995 BUG_ON(ret);
1996
1997 btrfs_set_super_log_root(&root->fs_info->super_for_commit,
1998 log->fs_info->log_root_tree->node->start);
1999 btrfs_set_super_log_root_level(&root->fs_info->super_for_commit,
2000 btrfs_header_level(log->fs_info->log_root_tree->node));
2001
2002 write_ctree_super(trans, log->fs_info->tree_root);
2003 log->fs_info->tree_log_transid++;
2004 log->fs_info->tree_log_batch = 0;
2005 atomic_set(&log->fs_info->tree_log_commit, 0);
2006 smp_mb();
2007 if (waitqueue_active(&log->fs_info->tree_log_wait))
2008 wake_up(&log->fs_info->tree_log_wait);
2009out:
2010 mutex_unlock(&log->fs_info->tree_log_mutex);
2011 return 0;
2012
2013}
2014
2015/* * free all the extents used by the tree log. This should be called
2016 * at commit time of the full transaction
2017 */
2018int btrfs_free_log(struct btrfs_trans_handle *trans, struct btrfs_root *root)
2019{
2020 int ret;
2021 struct btrfs_root *log;
2022 struct key;
2023 u64 start;
2024 u64 end;
2025 struct walk_control wc = {
2026 .free = 1,
2027 .process_func = process_one_buffer
2028 };
2029
2030 if (!root->log_root)
2031 return 0;
2032
2033 log = root->log_root;
2034 ret = walk_log_tree(trans, log, &wc);
2035 BUG_ON(ret);
2036
2037 while(1) {
2038 ret = find_first_extent_bit(&log->dirty_log_pages,
2039 0, &start, &end, EXTENT_DIRTY);
2040 if (ret)
2041 break;
2042
2043 clear_extent_dirty(&log->dirty_log_pages,
2044 start, end, GFP_NOFS);
2045 }
2046
2047 log = root->log_root;
2048 ret = btrfs_del_root(trans, root->fs_info->log_root_tree,
2049 &log->root_key);
2050 BUG_ON(ret);
2051 root->log_root = NULL;
2052 kfree(root->log_root);
2053 return 0;
2054}
2055
2056/*
2057 * helper function to update the item for a given subvolumes log root
2058 * in the tree of log roots
2059 */
2060static int update_log_root(struct btrfs_trans_handle *trans,
2061 struct btrfs_root *log)
2062{
2063 u64 bytenr = btrfs_root_bytenr(&log->root_item);
2064 int ret;
2065
2066 if (log->node->start == bytenr)
2067 return 0;
2068
2069 btrfs_set_root_bytenr(&log->root_item, log->node->start);
2070 btrfs_set_root_level(&log->root_item, btrfs_header_level(log->node));
2071 ret = btrfs_update_root(trans, log->fs_info->log_root_tree,
2072 &log->root_key, &log->root_item);
2073 BUG_ON(ret);
2074 return ret;
2075}
2076
2077/*
2078 * If both a file and directory are logged, and unlinks or renames are
2079 * mixed in, we have a few interesting corners:
2080 *
2081 * create file X in dir Y
2082 * link file X to X.link in dir Y
2083 * fsync file X
2084 * unlink file X but leave X.link
2085 * fsync dir Y
2086 *
2087 * After a crash we would expect only X.link to exist. But file X
2088 * didn't get fsync'd again so the log has back refs for X and X.link.
2089 *
2090 * We solve this by removing directory entries and inode backrefs from the
2091 * log when a file that was logged in the current transaction is
2092 * unlinked. Any later fsync will include the updated log entries, and
2093 * we'll be able to reconstruct the proper directory items from backrefs.
2094 *
2095 * This optimizations allows us to avoid relogging the entire inode
2096 * or the entire directory.
2097 */
2098int btrfs_del_dir_entries_in_log(struct btrfs_trans_handle *trans,
2099 struct btrfs_root *root,
2100 const char *name, int name_len,
2101 struct inode *dir, u64 index)
2102{
2103 struct btrfs_root *log;
2104 struct btrfs_dir_item *di;
2105 struct btrfs_path *path;
2106 int ret;
2107 int bytes_del = 0;
2108
2109 if (BTRFS_I(dir)->logged_trans < trans->transid)
2110 return 0;
2111
2112 ret = join_running_log_trans(root);
2113 if (ret)
2114 return 0;
2115
2116 mutex_lock(&BTRFS_I(dir)->log_mutex);
2117
2118 log = root->log_root;
2119 path = btrfs_alloc_path();
2120 di = btrfs_lookup_dir_item(trans, log, path, dir->i_ino,
2121 name, name_len, -1);
2122 if (di && !IS_ERR(di)) {
2123 ret = btrfs_delete_one_dir_name(trans, log, path, di);
2124 bytes_del += name_len;
2125 BUG_ON(ret);
2126 }
2127 btrfs_release_path(log, path);
2128 di = btrfs_lookup_dir_index_item(trans, log, path, dir->i_ino,
2129 index, name, name_len, -1);
2130 if (di && !IS_ERR(di)) {
2131 ret = btrfs_delete_one_dir_name(trans, log, path, di);
2132 bytes_del += name_len;
2133 BUG_ON(ret);
2134 }
2135
2136 /* update the directory size in the log to reflect the names
2137 * we have removed
2138 */
2139 if (bytes_del) {
2140 struct btrfs_key key;
2141
2142 key.objectid = dir->i_ino;
2143 key.offset = 0;
2144 key.type = BTRFS_INODE_ITEM_KEY;
2145 btrfs_release_path(log, path);
2146
2147 ret = btrfs_search_slot(trans, log, &key, path, 0, 1);
2148 if (ret == 0) {
2149 struct btrfs_inode_item *item;
2150 u64 i_size;
2151
2152 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2153 struct btrfs_inode_item);
2154 i_size = btrfs_inode_size(path->nodes[0], item);
2155 if (i_size > bytes_del)
2156 i_size -= bytes_del;
2157 else
2158 i_size = 0;
2159 btrfs_set_inode_size(path->nodes[0], item, i_size);
2160 btrfs_mark_buffer_dirty(path->nodes[0]);
2161 } else
2162 ret = 0;
2163 btrfs_release_path(log, path);
2164 }
2165
2166 btrfs_free_path(path);
2167 mutex_unlock(&BTRFS_I(dir)->log_mutex);
2168 end_log_trans(root);
2169
2170 return 0;
2171}
2172
2173/* see comments for btrfs_del_dir_entries_in_log */
2174int btrfs_del_inode_ref_in_log(struct btrfs_trans_handle *trans,
2175 struct btrfs_root *root,
2176 const char *name, int name_len,
2177 struct inode *inode, u64 dirid)
2178{
2179 struct btrfs_root *log;
2180 u64 index;
2181 int ret;
2182
2183 if (BTRFS_I(inode)->logged_trans < trans->transid)
2184 return 0;
2185
2186 ret = join_running_log_trans(root);
2187 if (ret)
2188 return 0;
2189 log = root->log_root;
2190 mutex_lock(&BTRFS_I(inode)->log_mutex);
2191
2192 ret = btrfs_del_inode_ref(trans, log, name, name_len, inode->i_ino,
2193 dirid, &index);
2194 mutex_unlock(&BTRFS_I(inode)->log_mutex);
2195 end_log_trans(root);
2196
2197 return ret;
2198}
2199
2200/*
2201 * creates a range item in the log for 'dirid'. first_offset and
2202 * last_offset tell us which parts of the key space the log should
2203 * be considered authoritative for.
2204 */
2205static noinline int insert_dir_log_key(struct btrfs_trans_handle *trans,
2206 struct btrfs_root *log,
2207 struct btrfs_path *path,
2208 int key_type, u64 dirid,
2209 u64 first_offset, u64 last_offset)
2210{
2211 int ret;
2212 struct btrfs_key key;
2213 struct btrfs_dir_log_item *item;
2214
2215 key.objectid = dirid;
2216 key.offset = first_offset;
2217 if (key_type == BTRFS_DIR_ITEM_KEY)
2218 key.type = BTRFS_DIR_LOG_ITEM_KEY;
2219 else
2220 key.type = BTRFS_DIR_LOG_INDEX_KEY;
2221 ret = btrfs_insert_empty_item(trans, log, path, &key, sizeof(*item));
2222 BUG_ON(ret);
2223
2224 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2225 struct btrfs_dir_log_item);
2226 btrfs_set_dir_log_end(path->nodes[0], item, last_offset);
2227 btrfs_mark_buffer_dirty(path->nodes[0]);
2228 btrfs_release_path(log, path);
2229 return 0;
2230}
2231
2232/*
2233 * log all the items included in the current transaction for a given
2234 * directory. This also creates the range items in the log tree required
2235 * to replay anything deleted before the fsync
2236 */
2237static noinline int log_dir_items(struct btrfs_trans_handle *trans,
2238 struct btrfs_root *root, struct inode *inode,
2239 struct btrfs_path *path,
2240 struct btrfs_path *dst_path, int key_type,
2241 u64 min_offset, u64 *last_offset_ret)
2242{
2243 struct btrfs_key min_key;
2244 struct btrfs_key max_key;
2245 struct btrfs_root *log = root->log_root;
2246 struct extent_buffer *src;
2247 int ret;
2248 int i;
2249 int nritems;
2250 u64 first_offset = min_offset;
2251 u64 last_offset = (u64)-1;
2252
2253 log = root->log_root;
2254 max_key.objectid = inode->i_ino;
2255 max_key.offset = (u64)-1;
2256 max_key.type = key_type;
2257
2258 min_key.objectid = inode->i_ino;
2259 min_key.type = key_type;
2260 min_key.offset = min_offset;
2261
2262 path->keep_locks = 1;
2263
2264 ret = btrfs_search_forward(root, &min_key, &max_key,
2265 path, 0, trans->transid);
2266
2267 /*
2268 * we didn't find anything from this transaction, see if there
2269 * is anything at all
2270 */
2271 if (ret != 0 || min_key.objectid != inode->i_ino ||
2272 min_key.type != key_type) {
2273 min_key.objectid = inode->i_ino;
2274 min_key.type = key_type;
2275 min_key.offset = (u64)-1;
2276 btrfs_release_path(root, path);
2277 ret = btrfs_search_slot(NULL, root, &min_key, path, 0, 0);
2278 if (ret < 0) {
2279 btrfs_release_path(root, path);
2280 return ret;
2281 }
2282 ret = btrfs_previous_item(root, path, inode->i_ino, key_type);
2283
2284 /* if ret == 0 there are items for this type,
2285 * create a range to tell us the last key of this type.
2286 * otherwise, there are no items in this directory after
2287 * *min_offset, and we create a range to indicate that.
2288 */
2289 if (ret == 0) {
2290 struct btrfs_key tmp;
2291 btrfs_item_key_to_cpu(path->nodes[0], &tmp,
2292 path->slots[0]);
2293 if (key_type == tmp.type) {
2294 first_offset = max(min_offset, tmp.offset) + 1;
2295 }
2296 }
2297 goto done;
2298 }
2299
2300 /* go backward to find any previous key */
2301 ret = btrfs_previous_item(root, path, inode->i_ino, key_type);
2302 if (ret == 0) {
2303 struct btrfs_key tmp;
2304 btrfs_item_key_to_cpu(path->nodes[0], &tmp, path->slots[0]);
2305 if (key_type == tmp.type) {
2306 first_offset = tmp.offset;
2307 ret = overwrite_item(trans, log, dst_path,
2308 path->nodes[0], path->slots[0],
2309 &tmp);
2310 }
2311 }
2312 btrfs_release_path(root, path);
2313
2314 /* find the first key from this transaction again */
2315 ret = btrfs_search_slot(NULL, root, &min_key, path, 0, 0);
2316 if (ret != 0) {
2317 WARN_ON(1);
2318 goto done;
2319 }
2320
2321 /*
2322 * we have a block from this transaction, log every item in it
2323 * from our directory
2324 */
2325 while(1) {
2326 struct btrfs_key tmp;
2327 src = path->nodes[0];
2328 nritems = btrfs_header_nritems(src);
2329 for (i = path->slots[0]; i < nritems; i++) {
2330 btrfs_item_key_to_cpu(src, &min_key, i);
2331
2332 if (min_key.objectid != inode->i_ino ||
2333 min_key.type != key_type)
2334 goto done;
2335 ret = overwrite_item(trans, log, dst_path, src, i,
2336 &min_key);
2337 BUG_ON(ret);
2338 }
2339 path->slots[0] = nritems;
2340
2341 /*
2342 * look ahead to the next item and see if it is also
2343 * from this directory and from this transaction
2344 */
2345 ret = btrfs_next_leaf(root, path);
2346 if (ret == 1) {
2347 last_offset = (u64)-1;
2348 goto done;
2349 }
2350 btrfs_item_key_to_cpu(path->nodes[0], &tmp, path->slots[0]);
2351 if (tmp.objectid != inode->i_ino || tmp.type != key_type) {
2352 last_offset = (u64)-1;
2353 goto done;
2354 }
2355 if (btrfs_header_generation(path->nodes[0]) != trans->transid) {
2356 ret = overwrite_item(trans, log, dst_path,
2357 path->nodes[0], path->slots[0],
2358 &tmp);
2359
2360 BUG_ON(ret);
2361 last_offset = tmp.offset;
2362 goto done;
2363 }
2364 }
2365done:
2366 *last_offset_ret = last_offset;
2367 btrfs_release_path(root, path);
2368 btrfs_release_path(log, dst_path);
2369
2370 /* insert the log range keys to indicate where the log is valid */
2371 ret = insert_dir_log_key(trans, log, path, key_type, inode->i_ino,
2372 first_offset, last_offset);
2373 BUG_ON(ret);
2374 return 0;
2375}
2376
2377/*
2378 * logging directories is very similar to logging inodes, We find all the items
2379 * from the current transaction and write them to the log.
2380 *
2381 * The recovery code scans the directory in the subvolume, and if it finds a
2382 * key in the range logged that is not present in the log tree, then it means
2383 * that dir entry was unlinked during the transaction.
2384 *
2385 * In order for that scan to work, we must include one key smaller than
2386 * the smallest logged by this transaction and one key larger than the largest
2387 * key logged by this transaction.
2388 */
2389static noinline int log_directory_changes(struct btrfs_trans_handle *trans,
2390 struct btrfs_root *root, struct inode *inode,
2391 struct btrfs_path *path,
2392 struct btrfs_path *dst_path)
2393{
2394 u64 min_key;
2395 u64 max_key;
2396 int ret;
2397 int key_type = BTRFS_DIR_ITEM_KEY;
2398
2399again:
2400 min_key = 0;
2401 max_key = 0;
2402 while(1) {
2403 ret = log_dir_items(trans, root, inode, path,
2404 dst_path, key_type, min_key,
2405 &max_key);
2406 BUG_ON(ret);
2407 if (max_key == (u64)-1)
2408 break;
2409 min_key = max_key + 1;
2410 }
2411
2412 if (key_type == BTRFS_DIR_ITEM_KEY) {
2413 key_type = BTRFS_DIR_INDEX_KEY;
2414 goto again;
2415 }
2416 return 0;
2417}
2418
2419/*
2420 * a helper function to drop items from the log before we relog an
2421 * inode. max_key_type indicates the highest item type to remove.
2422 * This cannot be run for file data extents because it does not
2423 * free the extents they point to.
2424 */
2425static int drop_objectid_items(struct btrfs_trans_handle *trans,
2426 struct btrfs_root *log,
2427 struct btrfs_path *path,
2428 u64 objectid, int max_key_type)
2429{
2430 int ret;
2431 struct btrfs_key key;
2432 struct btrfs_key found_key;
2433
2434 key.objectid = objectid;
2435 key.type = max_key_type;
2436 key.offset = (u64)-1;
2437
2438 while(1) {
2439 ret = btrfs_search_slot(trans, log, &key, path, -1, 1);
2440
2441 if (ret != 1)
2442 break;
2443
2444 if (path->slots[0] == 0)
2445 break;
2446
2447 path->slots[0]--;
2448 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
2449 path->slots[0]);
2450
2451 if (found_key.objectid != objectid)
2452 break;
2453
2454 ret = btrfs_del_item(trans, log, path);
2455 BUG_ON(ret);
2456 btrfs_release_path(log, path);
2457 }
2458 btrfs_release_path(log, path);
2459 return 0;
2460}
2461
2462static noinline int copy_items(struct btrfs_trans_handle *trans,
2463 struct btrfs_root *log,
2464 struct btrfs_path *dst_path,
2465 struct extent_buffer *src,
2466 int start_slot, int nr, int inode_only)
2467{
2468 unsigned long src_offset;
2469 unsigned long dst_offset;
2470 struct btrfs_file_extent_item *extent;
2471 struct btrfs_inode_item *inode_item;
2472 int ret;
2473 struct btrfs_key *ins_keys;
2474 u32 *ins_sizes;
2475 char *ins_data;
2476 int i;
2477
2478 ins_data = kmalloc(nr * sizeof(struct btrfs_key) +
2479 nr * sizeof(u32), GFP_NOFS);
2480 ins_sizes = (u32 *)ins_data;
2481 ins_keys = (struct btrfs_key *)(ins_data + nr * sizeof(u32));
2482
2483 for (i = 0; i < nr; i++) {
2484 ins_sizes[i] = btrfs_item_size_nr(src, i + start_slot);
2485 btrfs_item_key_to_cpu(src, ins_keys + i, i + start_slot);
2486 }
2487 ret = btrfs_insert_empty_items(trans, log, dst_path,
2488 ins_keys, ins_sizes, nr);
2489 BUG_ON(ret);
2490
2491 for (i = 0; i < nr; i++) {
2492 dst_offset = btrfs_item_ptr_offset(dst_path->nodes[0],
2493 dst_path->slots[0]);
2494
2495 src_offset = btrfs_item_ptr_offset(src, start_slot + i);
2496
2497 copy_extent_buffer(dst_path->nodes[0], src, dst_offset,
2498 src_offset, ins_sizes[i]);
2499
2500 if (inode_only == LOG_INODE_EXISTS &&
2501 ins_keys[i].type == BTRFS_INODE_ITEM_KEY) {
2502 inode_item = btrfs_item_ptr(dst_path->nodes[0],
2503 dst_path->slots[0],
2504 struct btrfs_inode_item);
2505 btrfs_set_inode_size(dst_path->nodes[0], inode_item, 0);
2506
2507 /* set the generation to zero so the recover code
2508 * can tell the difference between an logging
2509 * just to say 'this inode exists' and a logging
2510 * to say 'update this inode with these values'
2511 */
2512 btrfs_set_inode_generation(dst_path->nodes[0],
2513 inode_item, 0);
2514 }
2515 /* take a reference on file data extents so that truncates
2516 * or deletes of this inode don't have to relog the inode
2517 * again
2518 */
2519 if (btrfs_key_type(ins_keys + i) == BTRFS_EXTENT_DATA_KEY) {
2520 int found_type;
2521 extent = btrfs_item_ptr(src, start_slot + i,
2522 struct btrfs_file_extent_item);
2523
2524 found_type = btrfs_file_extent_type(src, extent);
2525 if (found_type == BTRFS_FILE_EXTENT_REG) {
2526 u64 ds = btrfs_file_extent_disk_bytenr(src,
2527 extent);
2528 u64 dl = btrfs_file_extent_disk_num_bytes(src,
2529 extent);
2530 /* ds == 0 is a hole */
2531 if (ds != 0) {
2532 ret = btrfs_inc_extent_ref(trans, log,
2533 ds, dl,
2534 dst_path->nodes[0]->start,
2535 BTRFS_TREE_LOG_OBJECTID,
2536 trans->transid,
2537 ins_keys[i].objectid,
2538 ins_keys[i].offset);
2539 BUG_ON(ret);
2540 }
2541 }
2542 }
2543 dst_path->slots[0]++;
2544 }
2545
2546 btrfs_mark_buffer_dirty(dst_path->nodes[0]);
2547 btrfs_release_path(log, dst_path);
2548 kfree(ins_data);
2549 return 0;
2550}
2551
2552/* log a single inode in the tree log.
2553 * At least one parent directory for this inode must exist in the tree
2554 * or be logged already.
2555 *
2556 * Any items from this inode changed by the current transaction are copied
2557 * to the log tree. An extra reference is taken on any extents in this
2558 * file, allowing us to avoid a whole pile of corner cases around logging
2559 * blocks that have been removed from the tree.
2560 *
2561 * See LOG_INODE_ALL and related defines for a description of what inode_only
2562 * does.
2563 *
2564 * This handles both files and directories.
2565 */
2566static int __btrfs_log_inode(struct btrfs_trans_handle *trans,
2567 struct btrfs_root *root, struct inode *inode,
2568 int inode_only)
2569{
2570 struct btrfs_path *path;
2571 struct btrfs_path *dst_path;
2572 struct btrfs_key min_key;
2573 struct btrfs_key max_key;
2574 struct btrfs_root *log = root->log_root;
2575 struct extent_buffer *src = NULL;
2576 u32 size;
2577 int ret;
2578 int nritems;
2579 int ins_start_slot = 0;
2580 int ins_nr;
2581
2582 log = root->log_root;
2583
2584 path = btrfs_alloc_path();
2585 dst_path = btrfs_alloc_path();
2586
2587 min_key.objectid = inode->i_ino;
2588 min_key.type = BTRFS_INODE_ITEM_KEY;
2589 min_key.offset = 0;
2590
2591 max_key.objectid = inode->i_ino;
2592 if (inode_only == LOG_INODE_EXISTS || S_ISDIR(inode->i_mode))
2593 max_key.type = BTRFS_XATTR_ITEM_KEY;
2594 else
2595 max_key.type = (u8)-1;
2596 max_key.offset = (u64)-1;
2597
2598 /*
2599 * if this inode has already been logged and we're in inode_only
2600 * mode, we don't want to delete the things that have already
2601 * been written to the log.
2602 *
2603 * But, if the inode has been through an inode_only log,
2604 * the logged_trans field is not set. This allows us to catch
2605 * any new names for this inode in the backrefs by logging it
2606 * again
2607 */
2608 if (inode_only == LOG_INODE_EXISTS &&
2609 BTRFS_I(inode)->logged_trans == trans->transid) {
2610 btrfs_free_path(path);
2611 btrfs_free_path(dst_path);
2612 goto out;
2613 }
2614 mutex_lock(&BTRFS_I(inode)->log_mutex);
2615
2616 /*
2617 * a brute force approach to making sure we get the most uptodate
2618 * copies of everything.
2619 */
2620 if (S_ISDIR(inode->i_mode)) {
2621 int max_key_type = BTRFS_DIR_LOG_INDEX_KEY;
2622
2623 if (inode_only == LOG_INODE_EXISTS)
2624 max_key_type = BTRFS_XATTR_ITEM_KEY;
2625 ret = drop_objectid_items(trans, log, path,
2626 inode->i_ino, max_key_type);
2627 } else {
2628 ret = btrfs_truncate_inode_items(trans, log, inode, 0, 0);
2629 }
2630 BUG_ON(ret);
2631 path->keep_locks = 1;
2632
2633 while(1) {
2634 ins_nr = 0;
2635 ret = btrfs_search_forward(root, &min_key, &max_key,
2636 path, 0, trans->transid);
2637 if (ret != 0)
2638 break;
2639again:
2640 /* note, ins_nr might be > 0 here, cleanup outside the loop */
2641 if (min_key.objectid != inode->i_ino)
2642 break;
2643 if (min_key.type > max_key.type)
2644 break;
2645
2646 src = path->nodes[0];
2647 size = btrfs_item_size_nr(src, path->slots[0]);
2648 if (ins_nr && ins_start_slot + ins_nr == path->slots[0]) {
2649 ins_nr++;
2650 goto next_slot;
2651 } else if (!ins_nr) {
2652 ins_start_slot = path->slots[0];
2653 ins_nr = 1;
2654 goto next_slot;
2655 }
2656
2657 ret = copy_items(trans, log, dst_path, src, ins_start_slot,
2658 ins_nr, inode_only);
2659 BUG_ON(ret);
2660 ins_nr = 1;
2661 ins_start_slot = path->slots[0];
2662next_slot:
2663
2664 nritems = btrfs_header_nritems(path->nodes[0]);
2665 path->slots[0]++;
2666 if (path->slots[0] < nritems) {
2667 btrfs_item_key_to_cpu(path->nodes[0], &min_key,
2668 path->slots[0]);
2669 goto again;
2670 }
2671 if (ins_nr) {
2672 ret = copy_items(trans, log, dst_path, src,
2673 ins_start_slot,
2674 ins_nr, inode_only);
2675 BUG_ON(ret);
2676 ins_nr = 0;
2677 }
2678 btrfs_release_path(root, path);
2679
2680 if (min_key.offset < (u64)-1)
2681 min_key.offset++;
2682 else if (min_key.type < (u8)-1)
2683 min_key.type++;
2684 else if (min_key.objectid < (u64)-1)
2685 min_key.objectid++;
2686 else
2687 break;
2688 }
2689 if (ins_nr) {
2690 ret = copy_items(trans, log, dst_path, src,
2691 ins_start_slot,
2692 ins_nr, inode_only);
2693 BUG_ON(ret);
2694 ins_nr = 0;
2695 }
2696 WARN_ON(ins_nr);
2697 if (inode_only == LOG_INODE_ALL && S_ISDIR(inode->i_mode)) {
2698 btrfs_release_path(root, path);
2699 btrfs_release_path(log, dst_path);
2700 BTRFS_I(inode)->log_dirty_trans = 0;
2701 ret = log_directory_changes(trans, root, inode, path, dst_path);
2702 BUG_ON(ret);
2703 }
2704 BTRFS_I(inode)->logged_trans = trans->transid;
2705 mutex_unlock(&BTRFS_I(inode)->log_mutex);
2706
2707 btrfs_free_path(path);
2708 btrfs_free_path(dst_path);
2709
2710 mutex_lock(&root->fs_info->tree_log_mutex);
2711 ret = update_log_root(trans, log);
2712 BUG_ON(ret);
2713 mutex_unlock(&root->fs_info->tree_log_mutex);
2714out:
2715 return 0;
2716}
2717
2718int btrfs_log_inode(struct btrfs_trans_handle *trans,
2719 struct btrfs_root *root, struct inode *inode,
2720 int inode_only)
2721{
2722 int ret;
2723
2724 start_log_trans(trans, root);
2725 ret = __btrfs_log_inode(trans, root, inode, inode_only);
2726 end_log_trans(root);
2727 return ret;
2728}
2729
2730/*
2731 * helper function around btrfs_log_inode to make sure newly created
2732 * parent directories also end up in the log. A minimal inode and backref
2733 * only logging is done of any parent directories that are older than
2734 * the last committed transaction
2735 */
2736int btrfs_log_dentry(struct btrfs_trans_handle *trans,
2737 struct btrfs_root *root, struct dentry *dentry)
2738{
2739 int inode_only = LOG_INODE_ALL;
2740 struct super_block *sb;
2741 int ret;
2742
2743 start_log_trans(trans, root);
2744 sb = dentry->d_inode->i_sb;
2745 while(1) {
2746 ret = __btrfs_log_inode(trans, root, dentry->d_inode,
2747 inode_only);
2748 BUG_ON(ret);
2749 inode_only = LOG_INODE_EXISTS;
2750
2751 dentry = dentry->d_parent;
2752 if (!dentry || !dentry->d_inode || sb != dentry->d_inode->i_sb)
2753 break;
2754
2755 if (BTRFS_I(dentry->d_inode)->generation <=
2756 root->fs_info->last_trans_committed)
2757 break;
2758 }
2759 end_log_trans(root);
2760 return 0;
2761}
2762
2763/*
2764 * it is not safe to log dentry if the chunk root has added new
2765 * chunks. This returns 0 if the dentry was logged, and 1 otherwise.
2766 * If this returns 1, you must commit the transaction to safely get your
2767 * data on disk.
2768 */
2769int btrfs_log_dentry_safe(struct btrfs_trans_handle *trans,
2770 struct btrfs_root *root, struct dentry *dentry)
2771{
2772 u64 gen;
2773 gen = root->fs_info->last_trans_new_blockgroup;
2774 if (gen > root->fs_info->last_trans_committed)
2775 return 1;
2776 else
2777 return btrfs_log_dentry(trans, root, dentry);
2778}
2779
2780/*
2781 * should be called during mount to recover any replay any log trees
2782 * from the FS
2783 */
2784int btrfs_recover_log_trees(struct btrfs_root *log_root_tree)
2785{
2786 int ret;
2787 struct btrfs_path *path;
2788 struct btrfs_trans_handle *trans;
2789 struct btrfs_key key;
2790 struct btrfs_key found_key;
2791 struct btrfs_key tmp_key;
2792 struct btrfs_root *log;
2793 struct btrfs_fs_info *fs_info = log_root_tree->fs_info;
2794 u64 highest_inode;
2795 struct walk_control wc = {
2796 .process_func = process_one_buffer,
2797 .stage = 0,
2798 };
2799
2800 fs_info->log_root_recovering = 1;
2801 path = btrfs_alloc_path();
2802 BUG_ON(!path);
2803
2804 trans = btrfs_start_transaction(fs_info->tree_root, 1);
2805
2806 wc.trans = trans;
2807 wc.pin = 1;
2808
2809 walk_log_tree(trans, log_root_tree, &wc);
2810
2811again:
2812 key.objectid = BTRFS_TREE_LOG_OBJECTID;
2813 key.offset = (u64)-1;
2814 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
2815
2816 while(1) {
2817 ret = btrfs_search_slot(NULL, log_root_tree, &key, path, 0, 0);
2818 if (ret < 0)
2819 break;
2820 if (ret > 0) {
2821 if (path->slots[0] == 0)
2822 break;
2823 path->slots[0]--;
2824 }
2825 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
2826 path->slots[0]);
2827 btrfs_release_path(log_root_tree, path);
2828 if (found_key.objectid != BTRFS_TREE_LOG_OBJECTID)
2829 break;
2830
2831 log = btrfs_read_fs_root_no_radix(log_root_tree,
2832 &found_key);
2833 BUG_ON(!log);
2834
2835
2836 tmp_key.objectid = found_key.offset;
2837 tmp_key.type = BTRFS_ROOT_ITEM_KEY;
2838 tmp_key.offset = (u64)-1;
2839
2840 wc.replay_dest = btrfs_read_fs_root_no_name(fs_info, &tmp_key);
2841
2842 BUG_ON(!wc.replay_dest);
2843
2844 btrfs_record_root_in_trans(wc.replay_dest);
2845 ret = walk_log_tree(trans, log, &wc);
2846 BUG_ON(ret);
2847
2848 if (wc.stage == LOG_WALK_REPLAY_ALL) {
2849 ret = fixup_inode_link_counts(trans, wc.replay_dest,
2850 path);
2851 BUG_ON(ret);
2852 }
2853 ret = btrfs_find_highest_inode(wc.replay_dest, &highest_inode);
2854 if (ret == 0) {
2855 wc.replay_dest->highest_inode = highest_inode;
2856 wc.replay_dest->last_inode_alloc = highest_inode;
2857 }
2858
2859 key.offset = found_key.offset - 1;
2860 free_extent_buffer(log->node);
2861 kfree(log);
2862
2863 if (found_key.offset == 0)
2864 break;
2865 }
2866 btrfs_release_path(log_root_tree, path);
2867
2868 /* step one is to pin it all, step two is to replay just inodes */
2869 if (wc.pin) {
2870 wc.pin = 0;
2871 wc.process_func = replay_one_buffer;
2872 wc.stage = LOG_WALK_REPLAY_INODES;
2873 goto again;
2874 }
2875 /* step three is to replay everything */
2876 if (wc.stage < LOG_WALK_REPLAY_ALL) {
2877 wc.stage++;
2878 goto again;
2879 }
2880
2881 btrfs_free_path(path);
2882
2883 free_extent_buffer(log_root_tree->node);
2884 log_root_tree->log_root = NULL;
2885 fs_info->log_root_recovering = 0;
2886
2887 /* step 4: commit the transaction, which also unpins the blocks */
2888 btrfs_commit_transaction(trans, fs_info->tree_root);
2889
2890 kfree(log_root_tree);
2891 return 0;
2892}
generated by cgit v1.2.2 (git 2.25.0) at 2025-09-04 01:03:36 -0400