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-rw-r--r--fs/btrfs/tree-log.c2996
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diff --git a/fs/btrfs/tree-log.c 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#include "tree-log.h"
27
28/* magic values for the inode_only field in btrfs_log_inode:
29 *
30 * LOG_INODE_ALL means to log everything
31 * LOG_INODE_EXISTS means to log just enough to recreate the inode
32 * during log replay
33 */
34#define LOG_INODE_ALL 0
35#define LOG_INODE_EXISTS 1
36
37/*
38 * stages for the tree walking. The first
39 * stage (0) is to only pin down the blocks we find
40 * the second stage (1) is to make sure that all the inodes
41 * we find in the log are created in the subvolume.
42 *
43 * The last stage is to deal with directories and links and extents
44 * and all the other fun semantics
45 */
46#define LOG_WALK_PIN_ONLY 0
47#define LOG_WALK_REPLAY_INODES 1
48#define LOG_WALK_REPLAY_ALL 2
49
50static int __btrfs_log_inode(struct btrfs_trans_handle *trans,
51 struct btrfs_root *root, struct inode *inode,
52 int inode_only);
53static int link_to_fixup_dir(struct btrfs_trans_handle *trans,
54 struct btrfs_root *root,
55 struct btrfs_path *path, u64 objectid);
56
57/*
58 * tree logging is a special write ahead log used to make sure that
59 * fsyncs and O_SYNCs can happen without doing full tree commits.
60 *
61 * Full tree commits are expensive because they require commonly
62 * modified blocks to be recowed, creating many dirty pages in the
63 * extent tree an 4x-6x higher write load than ext3.
64 *
65 * Instead of doing a tree commit on every fsync, we use the
66 * key ranges and transaction ids to find items for a given file or directory
67 * that have changed in this transaction. Those items are copied into
68 * a special tree (one per subvolume root), that tree is written to disk
69 * and then the fsync is considered complete.
70 *
71 * After a crash, items are copied out of the log-tree back into the
72 * subvolume tree. Any file data extents found are recorded in the extent
73 * allocation tree, and the log-tree freed.
74 *
75 * The log tree is read three times, once to pin down all the extents it is
76 * using in ram and once, once to create all the inodes logged in the tree
77 * and once to do all the other items.
78 */
79
80/*
81 * btrfs_add_log_tree adds a new per-subvolume log tree into the
82 * tree of log tree roots. This must be called with a tree log transaction
83 * running (see start_log_trans).
84 */
85static int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
86 struct btrfs_root *root)
87{
88 struct btrfs_key key;
89 struct btrfs_root_item root_item;
90 struct btrfs_inode_item *inode_item;
91 struct extent_buffer *leaf;
92 struct btrfs_root *new_root = root;
93 int ret;
94 u64 objectid = root->root_key.objectid;
95
96 leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 0,
97 BTRFS_TREE_LOG_OBJECTID,
98 trans->transid, 0, 0, 0);
99 if (IS_ERR(leaf)) {
100 ret = PTR_ERR(leaf);
101 return ret;
102 }
103
104 btrfs_set_header_nritems(leaf, 0);
105 btrfs_set_header_level(leaf, 0);
106 btrfs_set_header_bytenr(leaf, leaf->start);
107 btrfs_set_header_generation(leaf, trans->transid);
108 btrfs_set_header_owner(leaf, BTRFS_TREE_LOG_OBJECTID);
109
110 write_extent_buffer(leaf, root->fs_info->fsid,
111 (unsigned long)btrfs_header_fsid(leaf),
112 BTRFS_FSID_SIZE);
113 btrfs_mark_buffer_dirty(leaf);
114
115 inode_item = &root_item.inode;
116 memset(inode_item, 0, sizeof(*inode_item));
117 inode_item->generation = cpu_to_le64(1);
118 inode_item->size = cpu_to_le64(3);
119 inode_item->nlink = cpu_to_le32(1);
120 inode_item->nbytes = cpu_to_le64(root->leafsize);
121 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
122
123 btrfs_set_root_bytenr(&root_item, leaf->start);
124 btrfs_set_root_generation(&root_item, trans->transid);
125 btrfs_set_root_level(&root_item, 0);
126 btrfs_set_root_refs(&root_item, 0);
127 btrfs_set_root_used(&root_item, 0);
128
129 memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
130 root_item.drop_level = 0;
131
132 btrfs_tree_unlock(leaf);
133 free_extent_buffer(leaf);
134 leaf = NULL;
135
136 btrfs_set_root_dirid(&root_item, 0);
137
138 key.objectid = BTRFS_TREE_LOG_OBJECTID;
139 key.offset = objectid;
140 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
141 ret = btrfs_insert_root(trans, root->fs_info->log_root_tree, &key,
142 &root_item);
143 if (ret)
144 goto fail;
145
146 new_root = btrfs_read_fs_root_no_radix(root->fs_info->log_root_tree,
147 &key);
148 BUG_ON(!new_root);
149
150 WARN_ON(root->log_root);
151 root->log_root = new_root;
152
153 /*
154 * log trees do not get reference counted because they go away
155 * before a real commit is actually done. They do store pointers
156 * to file data extents, and those reference counts still get
157 * updated (along with back refs to the log tree).
158 */
159 new_root->ref_cows = 0;
160 new_root->last_trans = trans->transid;
161fail:
162 return ret;
163}
164
165/*
166 * start a sub transaction and setup the log tree
167 * this increments the log tree writer count to make the people
168 * syncing the tree wait for us to finish
169 */
170static int start_log_trans(struct btrfs_trans_handle *trans,
171 struct btrfs_root *root)
172{
173 int ret;
174 mutex_lock(&root->fs_info->tree_log_mutex);
175 if (!root->fs_info->log_root_tree) {
176 ret = btrfs_init_log_root_tree(trans, root->fs_info);
177 BUG_ON(ret);
178 }
179 if (!root->log_root) {
180 ret = btrfs_add_log_tree(trans, root);
181 BUG_ON(ret);
182 }
183 atomic_inc(&root->fs_info->tree_log_writers);
184 root->fs_info->tree_log_batch++;
185 mutex_unlock(&root->fs_info->tree_log_mutex);
186 return 0;
187}
188
189/*
190 * returns 0 if there was a log transaction running and we were able
191 * to join, or returns -ENOENT if there were not transactions
192 * in progress
193 */
194static int join_running_log_trans(struct btrfs_root *root)
195{
196 int ret = -ENOENT;
197
198 smp_mb();
199 if (!root->log_root)
200 return -ENOENT;
201
202 mutex_lock(&root->fs_info->tree_log_mutex);
203 if (root->log_root) {
204 ret = 0;
205 atomic_inc(&root->fs_info->tree_log_writers);
206 root->fs_info->tree_log_batch++;
207 }
208 mutex_unlock(&root->fs_info->tree_log_mutex);
209 return ret;
210}
211
212/*
213 * indicate we're done making changes to the log tree
214 * and wake up anyone waiting to do a sync
215 */
216static int end_log_trans(struct btrfs_root *root)
217{
218 atomic_dec(&root->fs_info->tree_log_writers);
219 smp_mb();
220 if (waitqueue_active(&root->fs_info->tree_log_wait))
221 wake_up(&root->fs_info->tree_log_wait);
222 return 0;
223}
224
225
226/*
227 * the walk control struct is used to pass state down the chain when
228 * processing the log tree. The stage field tells us which part
229 * of the log tree processing we are currently doing. The others
230 * are state fields used for that specific part
231 */
232struct walk_control {
233 /* should we free the extent on disk when done? This is used
234 * at transaction commit time while freeing a log tree
235 */
236 int free;
237
238 /* should we write out the extent buffer? This is used
239 * while flushing the log tree to disk during a sync
240 */
241 int write;
242
243 /* should we wait for the extent buffer io to finish? Also used
244 * while flushing the log tree to disk for a sync
245 */
246 int wait;
247
248 /* pin only walk, we record which extents on disk belong to the
249 * log trees
250 */
251 int pin;
252
253 /* what stage of the replay code we're currently in */
254 int stage;
255
256 /* the root we are currently replaying */
257 struct btrfs_root *replay_dest;
258
259 /* the trans handle for the current replay */
260 struct btrfs_trans_handle *trans;
261
262 /* the function that gets used to process blocks we find in the
263 * tree. Note the extent_buffer might not be up to date when it is
264 * passed in, and it must be checked or read if you need the data
265 * inside it
266 */
267 int (*process_func)(struct btrfs_root *log, struct extent_buffer *eb,
268 struct walk_control *wc, u64 gen);
269};
270
271/*
272 * process_func used to pin down extents, write them or wait on them
273 */
274static int process_one_buffer(struct btrfs_root *log,
275 struct extent_buffer *eb,
276 struct walk_control *wc, u64 gen)
277{
278 if (wc->pin) {
279 mutex_lock(&log->fs_info->pinned_mutex);
280 btrfs_update_pinned_extents(log->fs_info->extent_root,
281 eb->start, eb->len, 1);
282 mutex_unlock(&log->fs_info->pinned_mutex);
283 }
284
285 if (btrfs_buffer_uptodate(eb, gen)) {
286 if (wc->write)
287 btrfs_write_tree_block(eb);
288 if (wc->wait)
289 btrfs_wait_tree_block_writeback(eb);
290 }
291 return 0;
292}
293
294/*
295 * Item overwrite used by replay and tree logging. eb, slot and key all refer
296 * to the src data we are copying out.
297 *
298 * root is the tree we are copying into, and path is a scratch
299 * path for use in this function (it should be released on entry and
300 * will be released on exit).
301 *
302 * If the key is already in the destination tree the existing item is
303 * overwritten. If the existing item isn't big enough, it is extended.
304 * If it is too large, it is truncated.
305 *
306 * If the key isn't in the destination yet, a new item is inserted.
307 */
308static noinline int overwrite_item(struct btrfs_trans_handle *trans,
309 struct btrfs_root *root,
310 struct btrfs_path *path,
311 struct extent_buffer *eb, int slot,
312 struct btrfs_key *key)
313{
314 int ret;
315 u32 item_size;
316 u64 saved_i_size = 0;
317 int save_old_i_size = 0;
318 unsigned long src_ptr;
319 unsigned long dst_ptr;
320 int overwrite_root = 0;
321
322 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID)
323 overwrite_root = 1;
324
325 item_size = btrfs_item_size_nr(eb, slot);
326 src_ptr = btrfs_item_ptr_offset(eb, slot);
327
328 /* look for the key in the destination tree */
329 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
330 if (ret == 0) {
331 char *src_copy;
332 char *dst_copy;
333 u32 dst_size = btrfs_item_size_nr(path->nodes[0],
334 path->slots[0]);
335 if (dst_size != item_size)
336 goto insert;
337
338 if (item_size == 0) {
339 btrfs_release_path(root, path);
340 return 0;
341 }
342 dst_copy = kmalloc(item_size, GFP_NOFS);
343 src_copy = kmalloc(item_size, GFP_NOFS);
344
345 read_extent_buffer(eb, src_copy, src_ptr, item_size);
346
347 dst_ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
348 read_extent_buffer(path->nodes[0], dst_copy, dst_ptr,
349 item_size);
350 ret = memcmp(dst_copy, src_copy, item_size);
351
352 kfree(dst_copy);
353 kfree(src_copy);
354 /*
355 * they have the same contents, just return, this saves
356 * us from cowing blocks in the destination tree and doing
357 * extra writes that may not have been done by a previous
358 * sync
359 */
360 if (ret == 0) {
361 btrfs_release_path(root, path);
362 return 0;
363 }
364
365 }
366insert:
367 btrfs_release_path(root, path);
368 /* try to insert the key into the destination tree */
369 ret = btrfs_insert_empty_item(trans, root, path,
370 key, item_size);
371
372 /* make sure any existing item is the correct size */
373 if (ret == -EEXIST) {
374 u32 found_size;
375 found_size = btrfs_item_size_nr(path->nodes[0],
376 path->slots[0]);
377 if (found_size > item_size) {
378 btrfs_truncate_item(trans, root, path, item_size, 1);
379 } else if (found_size < item_size) {
380 ret = btrfs_extend_item(trans, root, path,
381 item_size - found_size);
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 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
446 struct btrfs_key ins;
447 ins.objectid = btrfs_file_extent_disk_bytenr(
448 path->nodes[0], fi);
449 ins.offset = btrfs_file_extent_disk_num_bytes(
450 path->nodes[0], fi);
451 ins.type = BTRFS_EXTENT_ITEM_KEY;
452
453 /*
454 * is this extent already allocated in the extent
455 * allocation tree? If so, just add a reference
456 */
457 ret = btrfs_lookup_extent(root, ins.objectid,
458 ins.offset);
459 if (ret == 0) {
460 ret = btrfs_inc_extent_ref(trans, root,
461 ins.objectid, ins.offset,
462 path->nodes[0]->start,
463 root->root_key.objectid,
464 trans->transid, key->objectid);
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 &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 found_type == BTRFS_FILE_EXTENT_PREALLOC)
543 extent_end = start + btrfs_file_extent_num_bytes(eb, item);
544 else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
545 size = btrfs_file_extent_inline_len(eb, item);
546 extent_end = (start + size + mask) & ~mask;
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 &&
567 (found_type == BTRFS_FILE_EXTENT_REG ||
568 found_type == BTRFS_FILE_EXTENT_PREALLOC)) {
569 struct btrfs_file_extent_item cmp1;
570 struct btrfs_file_extent_item cmp2;
571 struct btrfs_file_extent_item *existing;
572 struct extent_buffer *leaf;
573
574 leaf = path->nodes[0];
575 existing = btrfs_item_ptr(leaf, path->slots[0],
576 struct btrfs_file_extent_item);
577
578 read_extent_buffer(eb, &cmp1, (unsigned long)item,
579 sizeof(cmp1));
580 read_extent_buffer(leaf, &cmp2, (unsigned long)existing,
581 sizeof(cmp2));
582
583 /*
584 * we already have a pointer to this exact extent,
585 * we don't have to do anything
586 */
587 if (memcmp(&cmp1, &cmp2, sizeof(cmp1)) == 0) {
588 btrfs_release_path(root, path);
589 goto out;
590 }
591 }
592 btrfs_release_path(root, path);
593
594 /* drop any overlapping extents */
595 ret = btrfs_drop_extents(trans, root, inode,
596 start, extent_end, start, &alloc_hint);
597 BUG_ON(ret);
598
599 /* insert the extent */
600 ret = overwrite_item(trans, root, path, eb, slot, key);
601 BUG_ON(ret);
602
603 /* btrfs_drop_extents changes i_bytes & i_blocks, update it here */
604 inode_add_bytes(inode, extent_end - start);
605 btrfs_update_inode(trans, root, inode);
606out:
607 if (inode)
608 iput(inode);
609 return ret;
610}
611
612/*
613 * when cleaning up conflicts between the directory names in the
614 * subvolume, directory names in the log and directory names in the
615 * inode back references, we may have to unlink inodes from directories.
616 *
617 * This is a helper function to do the unlink of a specific directory
618 * item
619 */
620static noinline int drop_one_dir_item(struct btrfs_trans_handle *trans,
621 struct btrfs_root *root,
622 struct btrfs_path *path,
623 struct inode *dir,
624 struct btrfs_dir_item *di)
625{
626 struct inode *inode;
627 char *name;
628 int name_len;
629 struct extent_buffer *leaf;
630 struct btrfs_key location;
631 int ret;
632
633 leaf = path->nodes[0];
634
635 btrfs_dir_item_key_to_cpu(leaf, di, &location);
636 name_len = btrfs_dir_name_len(leaf, di);
637 name = kmalloc(name_len, GFP_NOFS);
638 read_extent_buffer(leaf, name, (unsigned long)(di + 1), name_len);
639 btrfs_release_path(root, path);
640
641 inode = read_one_inode(root, location.objectid);
642 BUG_ON(!inode);
643
644 ret = link_to_fixup_dir(trans, root, path, location.objectid);
645 BUG_ON(ret);
646 ret = btrfs_unlink_inode(trans, root, dir, inode, name, name_len);
647 BUG_ON(ret);
648 kfree(name);
649
650 iput(inode);
651 return ret;
652}
653
654/*
655 * helper function to see if a given name and sequence number found
656 * in an inode back reference are already in a directory and correctly
657 * point to this inode
658 */
659static noinline int inode_in_dir(struct btrfs_root *root,
660 struct btrfs_path *path,
661 u64 dirid, u64 objectid, u64 index,
662 const char *name, int name_len)
663{
664 struct btrfs_dir_item *di;
665 struct btrfs_key location;
666 int match = 0;
667
668 di = btrfs_lookup_dir_index_item(NULL, root, path, dirid,
669 index, name, name_len, 0);
670 if (di && !IS_ERR(di)) {
671 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location);
672 if (location.objectid != objectid)
673 goto out;
674 } else
675 goto out;
676 btrfs_release_path(root, path);
677
678 di = btrfs_lookup_dir_item(NULL, root, path, dirid, name, name_len, 0);
679 if (di && !IS_ERR(di)) {
680 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location);
681 if (location.objectid != objectid)
682 goto out;
683 } else
684 goto out;
685 match = 1;
686out:
687 btrfs_release_path(root, path);
688 return match;
689}
690
691/*
692 * helper function to check a log tree for a named back reference in
693 * an inode. This is used to decide if a back reference that is
694 * found in the subvolume conflicts with what we find in the log.
695 *
696 * inode backreferences may have multiple refs in a single item,
697 * during replay we process one reference at a time, and we don't
698 * want to delete valid links to a file from the subvolume if that
699 * link is also in the log.
700 */
701static noinline int backref_in_log(struct btrfs_root *log,
702 struct btrfs_key *key,
703 char *name, int namelen)
704{
705 struct btrfs_path *path;
706 struct btrfs_inode_ref *ref;
707 unsigned long ptr;
708 unsigned long ptr_end;
709 unsigned long name_ptr;
710 int found_name_len;
711 int item_size;
712 int ret;
713 int match = 0;
714
715 path = btrfs_alloc_path();
716 ret = btrfs_search_slot(NULL, log, key, path, 0, 0);
717 if (ret != 0)
718 goto out;
719
720 item_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]);
721 ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
722 ptr_end = ptr + item_size;
723 while (ptr < ptr_end) {
724 ref = (struct btrfs_inode_ref *)ptr;
725 found_name_len = btrfs_inode_ref_name_len(path->nodes[0], ref);
726 if (found_name_len == namelen) {
727 name_ptr = (unsigned long)(ref + 1);
728 ret = memcmp_extent_buffer(path->nodes[0], name,
729 name_ptr, namelen);
730 if (ret == 0) {
731 match = 1;
732 goto out;
733 }
734 }
735 ptr = (unsigned long)(ref + 1) + found_name_len;
736 }
737out:
738 btrfs_free_path(path);
739 return match;
740}
741
742
743/*
744 * replay one inode back reference item found in the log tree.
745 * eb, slot and key refer to the buffer and key found in the log tree.
746 * root is the destination we are replaying into, and path is for temp
747 * use by this function. (it should be released on return).
748 */
749static noinline int add_inode_ref(struct btrfs_trans_handle *trans,
750 struct btrfs_root *root,
751 struct btrfs_root *log,
752 struct btrfs_path *path,
753 struct extent_buffer *eb, int slot,
754 struct btrfs_key *key)
755{
756 struct inode *dir;
757 int ret;
758 struct btrfs_key location;
759 struct btrfs_inode_ref *ref;
760 struct btrfs_dir_item *di;
761 struct inode *inode;
762 char *name;
763 int namelen;
764 unsigned long ref_ptr;
765 unsigned long ref_end;
766
767 location.objectid = key->objectid;
768 location.type = BTRFS_INODE_ITEM_KEY;
769 location.offset = 0;
770
771 /*
772 * it is possible that we didn't log all the parent directories
773 * for a given inode. If we don't find the dir, just don't
774 * copy the back ref in. The link count fixup code will take
775 * care of the rest
776 */
777 dir = read_one_inode(root, key->offset);
778 if (!dir)
779 return -ENOENT;
780
781 inode = read_one_inode(root, key->objectid);
782 BUG_ON(!dir);
783
784 ref_ptr = btrfs_item_ptr_offset(eb, slot);
785 ref_end = ref_ptr + btrfs_item_size_nr(eb, slot);
786
787again:
788 ref = (struct btrfs_inode_ref *)ref_ptr;
789
790 namelen = btrfs_inode_ref_name_len(eb, ref);
791 name = kmalloc(namelen, GFP_NOFS);
792 BUG_ON(!name);
793
794 read_extent_buffer(eb, name, (unsigned long)(ref + 1), namelen);
795
796 /* if we already have a perfect match, we're done */
797 if (inode_in_dir(root, path, dir->i_ino, inode->i_ino,
798 btrfs_inode_ref_index(eb, ref),
799 name, namelen)) {
800 goto out;
801 }
802
803 /*
804 * look for a conflicting back reference in the metadata.
805 * if we find one we have to unlink that name of the file
806 * before we add our new link. Later on, we overwrite any
807 * existing back reference, and we don't want to create
808 * dangling pointers in the directory.
809 */
810conflict_again:
811 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
812 if (ret == 0) {
813 char *victim_name;
814 int victim_name_len;
815 struct btrfs_inode_ref *victim_ref;
816 unsigned long ptr;
817 unsigned long ptr_end;
818 struct extent_buffer *leaf = path->nodes[0];
819
820 /* are we trying to overwrite a back ref for the root directory
821 * if so, just jump out, we're done
822 */
823 if (key->objectid == key->offset)
824 goto out_nowrite;
825
826 /* check all the names in this back reference to see
827 * if they are in the log. if so, we allow them to stay
828 * otherwise they must be unlinked as a conflict
829 */
830 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
831 ptr_end = ptr + btrfs_item_size_nr(leaf, path->slots[0]);
832 while (ptr < ptr_end) {
833 victim_ref = (struct btrfs_inode_ref *)ptr;
834 victim_name_len = btrfs_inode_ref_name_len(leaf,
835 victim_ref);
836 victim_name = kmalloc(victim_name_len, GFP_NOFS);
837 BUG_ON(!victim_name);
838
839 read_extent_buffer(leaf, victim_name,
840 (unsigned long)(victim_ref + 1),
841 victim_name_len);
842
843 if (!backref_in_log(log, key, victim_name,
844 victim_name_len)) {
845 btrfs_inc_nlink(inode);
846 btrfs_release_path(root, path);
847 ret = btrfs_unlink_inode(trans, root, dir,
848 inode, victim_name,
849 victim_name_len);
850 kfree(victim_name);
851 btrfs_release_path(root, path);
852 goto conflict_again;
853 }
854 kfree(victim_name);
855 ptr = (unsigned long)(victim_ref + 1) + victim_name_len;
856 }
857 BUG_ON(ret);
858 }
859 btrfs_release_path(root, path);
860
861 /* look for a conflicting sequence number */
862 di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
863 btrfs_inode_ref_index(eb, ref),
864 name, namelen, 0);
865 if (di && !IS_ERR(di)) {
866 ret = drop_one_dir_item(trans, root, path, dir, di);
867 BUG_ON(ret);
868 }
869 btrfs_release_path(root, path);
870
871
872 /* look for a conflicting name */
873 di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
874 name, namelen, 0);
875 if (di && !IS_ERR(di)) {
876 ret = drop_one_dir_item(trans, root, path, dir, di);
877 BUG_ON(ret);
878 }
879 btrfs_release_path(root, path);
880
881 /* insert our name */
882 ret = btrfs_add_link(trans, dir, inode, name, namelen, 0,
883 btrfs_inode_ref_index(eb, ref));
884 BUG_ON(ret);
885
886 btrfs_update_inode(trans, root, inode);
887
888out:
889 ref_ptr = (unsigned long)(ref + 1) + namelen;
890 kfree(name);
891 if (ref_ptr < ref_end)
892 goto again;
893
894 /* finally write the back reference in the inode */
895 ret = overwrite_item(trans, root, path, eb, slot, key);
896 BUG_ON(ret);
897
898out_nowrite:
899 btrfs_release_path(root, path);
900 iput(dir);
901 iput(inode);
902 return 0;
903}
904
905/*
906 * replay one csum item from the log tree into the subvolume 'root'
907 * eb, slot and key all refer to the log tree
908 * path is for temp use by this function and should be released on return
909 *
910 * This copies the checksums out of the log tree and inserts them into
911 * the subvolume. Any existing checksums for this range in the file
912 * are overwritten, and new items are added where required.
913 *
914 * We keep this simple by reusing the btrfs_ordered_sum code from
915 * the data=ordered mode. This basically means making a copy
916 * of all the checksums in ram, which we have to do anyway for kmap
917 * rules.
918 *
919 * The copy is then sent down to btrfs_csum_file_blocks, which
920 * does all the hard work of finding existing items in the file
921 * or adding new ones.
922 */
923static noinline int replay_one_csum(struct btrfs_trans_handle *trans,
924 struct btrfs_root *root,
925 struct btrfs_path *path,
926 struct extent_buffer *eb, int slot,
927 struct btrfs_key *key)
928{
929 int ret;
930 u32 item_size = btrfs_item_size_nr(eb, slot);
931 u64 cur_offset;
932 u16 csum_size =
933 btrfs_super_csum_size(&root->fs_info->super_copy);
934 unsigned long file_bytes;
935 struct btrfs_ordered_sum *sums;
936 struct btrfs_sector_sum *sector_sum;
937 unsigned long ptr;
938
939 file_bytes = (item_size / csum_size) * root->sectorsize;
940 sums = kzalloc(btrfs_ordered_sum_size(root, file_bytes), GFP_NOFS);
941 if (!sums)
942 return -ENOMEM;
943
944 INIT_LIST_HEAD(&sums->list);
945 sums->len = file_bytes;
946 sums->bytenr = key->offset;
947
948 /*
949 * copy all the sums into the ordered sum struct
950 */
951 sector_sum = sums->sums;
952 cur_offset = key->offset;
953 ptr = btrfs_item_ptr_offset(eb, slot);
954 while (item_size > 0) {
955 sector_sum->bytenr = cur_offset;
956 read_extent_buffer(eb, &sector_sum->sum, ptr, csum_size);
957 sector_sum++;
958 item_size -= csum_size;
959 ptr += csum_size;
960 cur_offset += root->sectorsize;
961 }
962
963 /* let btrfs_csum_file_blocks add them into the file */
964 ret = btrfs_csum_file_blocks(trans, root->fs_info->csum_root, sums);
965 BUG_ON(ret);
966 kfree(sums);
967 return 0;
968}
969/*
970 * There are a few corners where the link count of the file can't
971 * be properly maintained during replay. So, instead of adding
972 * lots of complexity to the log code, we just scan the backrefs
973 * for any file that has been through replay.
974 *
975 * The scan will update the link count on the inode to reflect the
976 * number of back refs found. If it goes down to zero, the iput
977 * will free the inode.
978 */
979static noinline int fixup_inode_link_count(struct btrfs_trans_handle *trans,
980 struct btrfs_root *root,
981 struct inode *inode)
982{
983 struct btrfs_path *path;
984 int ret;
985 struct btrfs_key key;
986 u64 nlink = 0;
987 unsigned long ptr;
988 unsigned long ptr_end;
989 int name_len;
990
991 key.objectid = inode->i_ino;
992 key.type = BTRFS_INODE_REF_KEY;
993 key.offset = (u64)-1;
994
995 path = btrfs_alloc_path();
996
997 while (1) {
998 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
999 if (ret < 0)
1000 break;
1001 if (ret > 0) {
1002 if (path->slots[0] == 0)
1003 break;
1004 path->slots[0]--;
1005 }
1006 btrfs_item_key_to_cpu(path->nodes[0], &key,
1007 path->slots[0]);
1008 if (key.objectid != inode->i_ino ||
1009 key.type != BTRFS_INODE_REF_KEY)
1010 break;
1011 ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
1012 ptr_end = ptr + btrfs_item_size_nr(path->nodes[0],
1013 path->slots[0]);
1014 while (ptr < ptr_end) {
1015 struct btrfs_inode_ref *ref;
1016
1017 ref = (struct btrfs_inode_ref *)ptr;
1018 name_len = btrfs_inode_ref_name_len(path->nodes[0],
1019 ref);
1020 ptr = (unsigned long)(ref + 1) + name_len;
1021 nlink++;
1022 }
1023
1024 if (key.offset == 0)
1025 break;
1026 key.offset--;
1027 btrfs_release_path(root, path);
1028 }
1029 btrfs_free_path(path);
1030 if (nlink != inode->i_nlink) {
1031 inode->i_nlink = nlink;
1032 btrfs_update_inode(trans, root, inode);
1033 }
1034 BTRFS_I(inode)->index_cnt = (u64)-1;
1035
1036 return 0;
1037}
1038
1039static noinline int fixup_inode_link_counts(struct btrfs_trans_handle *trans,
1040 struct btrfs_root *root,
1041 struct btrfs_path *path)
1042{
1043 int ret;
1044 struct btrfs_key key;
1045 struct inode *inode;
1046
1047 key.objectid = BTRFS_TREE_LOG_FIXUP_OBJECTID;
1048 key.type = BTRFS_ORPHAN_ITEM_KEY;
1049 key.offset = (u64)-1;
1050 while (1) {
1051 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1052 if (ret < 0)
1053 break;
1054
1055 if (ret == 1) {
1056 if (path->slots[0] == 0)
1057 break;
1058 path->slots[0]--;
1059 }
1060
1061 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1062 if (key.objectid != BTRFS_TREE_LOG_FIXUP_OBJECTID ||
1063 key.type != BTRFS_ORPHAN_ITEM_KEY)
1064 break;
1065
1066 ret = btrfs_del_item(trans, root, path);
1067 BUG_ON(ret);
1068
1069 btrfs_release_path(root, path);
1070 inode = read_one_inode(root, key.offset);
1071 BUG_ON(!inode);
1072
1073 ret = fixup_inode_link_count(trans, root, inode);
1074 BUG_ON(ret);
1075
1076 iput(inode);
1077
1078 if (key.offset == 0)
1079 break;
1080 key.offset--;
1081 }
1082 btrfs_release_path(root, path);
1083 return 0;
1084}
1085
1086
1087/*
1088 * record a given inode in the fixup dir so we can check its link
1089 * count when replay is done. The link count is incremented here
1090 * so the inode won't go away until we check it
1091 */
1092static noinline int link_to_fixup_dir(struct btrfs_trans_handle *trans,
1093 struct btrfs_root *root,
1094 struct btrfs_path *path,
1095 u64 objectid)
1096{
1097 struct btrfs_key key;
1098 int ret = 0;
1099 struct inode *inode;
1100
1101 inode = read_one_inode(root, objectid);
1102 BUG_ON(!inode);
1103
1104 key.objectid = BTRFS_TREE_LOG_FIXUP_OBJECTID;
1105 btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
1106 key.offset = objectid;
1107
1108 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1109
1110 btrfs_release_path(root, path);
1111 if (ret == 0) {
1112 btrfs_inc_nlink(inode);
1113 btrfs_update_inode(trans, root, inode);
1114 } else if (ret == -EEXIST) {
1115 ret = 0;
1116 } else {
1117 BUG();
1118 }
1119 iput(inode);
1120
1121 return ret;
1122}
1123
1124/*
1125 * when replaying the log for a directory, we only insert names
1126 * for inodes that actually exist. This means an fsync on a directory
1127 * does not implicitly fsync all the new files in it
1128 */
1129static noinline int insert_one_name(struct btrfs_trans_handle *trans,
1130 struct btrfs_root *root,
1131 struct btrfs_path *path,
1132 u64 dirid, u64 index,
1133 char *name, int name_len, u8 type,
1134 struct btrfs_key *location)
1135{
1136 struct inode *inode;
1137 struct inode *dir;
1138 int ret;
1139
1140 inode = read_one_inode(root, location->objectid);
1141 if (!inode)
1142 return -ENOENT;
1143
1144 dir = read_one_inode(root, dirid);
1145 if (!dir) {
1146 iput(inode);
1147 return -EIO;
1148 }
1149 ret = btrfs_add_link(trans, dir, inode, name, name_len, 1, index);
1150
1151 /* FIXME, put inode into FIXUP list */
1152
1153 iput(inode);
1154 iput(dir);
1155 return ret;
1156}
1157
1158/*
1159 * take a single entry in a log directory item and replay it into
1160 * the subvolume.
1161 *
1162 * if a conflicting item exists in the subdirectory already,
1163 * the inode it points to is unlinked and put into the link count
1164 * fix up tree.
1165 *
1166 * If a name from the log points to a file or directory that does
1167 * not exist in the FS, it is skipped. fsyncs on directories
1168 * do not force down inodes inside that directory, just changes to the
1169 * names or unlinks in a directory.
1170 */
1171static noinline int replay_one_name(struct btrfs_trans_handle *trans,
1172 struct btrfs_root *root,
1173 struct btrfs_path *path,
1174 struct extent_buffer *eb,
1175 struct btrfs_dir_item *di,
1176 struct btrfs_key *key)
1177{
1178 char *name;
1179 int name_len;
1180 struct btrfs_dir_item *dst_di;
1181 struct btrfs_key found_key;
1182 struct btrfs_key log_key;
1183 struct inode *dir;
1184 u8 log_type;
1185 int exists;
1186 int ret;
1187
1188 dir = read_one_inode(root, key->objectid);
1189 BUG_ON(!dir);
1190
1191 name_len = btrfs_dir_name_len(eb, di);
1192 name = kmalloc(name_len, GFP_NOFS);
1193 log_type = btrfs_dir_type(eb, di);
1194 read_extent_buffer(eb, name, (unsigned long)(di + 1),
1195 name_len);
1196
1197 btrfs_dir_item_key_to_cpu(eb, di, &log_key);
1198 exists = btrfs_lookup_inode(trans, root, path, &log_key, 0);
1199 if (exists == 0)
1200 exists = 1;
1201 else
1202 exists = 0;
1203 btrfs_release_path(root, path);
1204
1205 if (key->type == BTRFS_DIR_ITEM_KEY) {
1206 dst_di = btrfs_lookup_dir_item(trans, root, path, key->objectid,
1207 name, name_len, 1);
1208 } else if (key->type == BTRFS_DIR_INDEX_KEY) {
1209 dst_di = btrfs_lookup_dir_index_item(trans, root, path,
1210 key->objectid,
1211 key->offset, name,
1212 name_len, 1);
1213 } else {
1214 BUG();
1215 }
1216 if (!dst_di || IS_ERR(dst_di)) {
1217 /* we need a sequence number to insert, so we only
1218 * do inserts for the BTRFS_DIR_INDEX_KEY types
1219 */
1220 if (key->type != BTRFS_DIR_INDEX_KEY)
1221 goto out;
1222 goto insert;
1223 }
1224
1225 btrfs_dir_item_key_to_cpu(path->nodes[0], dst_di, &found_key);
1226 /* the existing item matches the logged item */
1227 if (found_key.objectid == log_key.objectid &&
1228 found_key.type == log_key.type &&
1229 found_key.offset == log_key.offset &&
1230 btrfs_dir_type(path->nodes[0], dst_di) == log_type) {
1231 goto out;
1232 }
1233
1234 /*
1235 * don't drop the conflicting directory entry if the inode
1236 * for the new entry doesn't exist
1237 */
1238 if (!exists)
1239 goto out;
1240
1241 ret = drop_one_dir_item(trans, root, path, dir, dst_di);
1242 BUG_ON(ret);
1243
1244 if (key->type == BTRFS_DIR_INDEX_KEY)
1245 goto insert;
1246out:
1247 btrfs_release_path(root, path);
1248 kfree(name);
1249 iput(dir);
1250 return 0;
1251
1252insert:
1253 btrfs_release_path(root, path);
1254 ret = insert_one_name(trans, root, path, key->objectid, key->offset,
1255 name, name_len, log_type, &log_key);
1256
1257 if (ret && ret != -ENOENT)
1258 BUG();
1259 goto out;
1260}
1261
1262/*
1263 * find all the names in a directory item and reconcile them into
1264 * the subvolume. Only BTRFS_DIR_ITEM_KEY types will have more than
1265 * one name in a directory item, but the same code gets used for
1266 * both directory index types
1267 */
1268static noinline int replay_one_dir_item(struct btrfs_trans_handle *trans,
1269 struct btrfs_root *root,
1270 struct btrfs_path *path,
1271 struct extent_buffer *eb, int slot,
1272 struct btrfs_key *key)
1273{
1274 int ret;
1275 u32 item_size = btrfs_item_size_nr(eb, slot);
1276 struct btrfs_dir_item *di;
1277 int name_len;
1278 unsigned long ptr;
1279 unsigned long ptr_end;
1280
1281 ptr = btrfs_item_ptr_offset(eb, slot);
1282 ptr_end = ptr + item_size;
1283 while (ptr < ptr_end) {
1284 di = (struct btrfs_dir_item *)ptr;
1285 name_len = btrfs_dir_name_len(eb, di);
1286 ret = replay_one_name(trans, root, path, eb, di, key);
1287 BUG_ON(ret);
1288 ptr = (unsigned long)(di + 1);
1289 ptr += name_len;
1290 }
1291 return 0;
1292}
1293
1294/*
1295 * directory replay has two parts. There are the standard directory
1296 * items in the log copied from the subvolume, and range items
1297 * created in the log while the subvolume was logged.
1298 *
1299 * The range items tell us which parts of the key space the log
1300 * is authoritative for. During replay, if a key in the subvolume
1301 * directory is in a logged range item, but not actually in the log
1302 * that means it was deleted from the directory before the fsync
1303 * and should be removed.
1304 */
1305static noinline int find_dir_range(struct btrfs_root *root,
1306 struct btrfs_path *path,
1307 u64 dirid, int key_type,
1308 u64 *start_ret, u64 *end_ret)
1309{
1310 struct btrfs_key key;
1311 u64 found_end;
1312 struct btrfs_dir_log_item *item;
1313 int ret;
1314 int nritems;
1315
1316 if (*start_ret == (u64)-1)
1317 return 1;
1318
1319 key.objectid = dirid;
1320 key.type = key_type;
1321 key.offset = *start_ret;
1322
1323 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1324 if (ret < 0)
1325 goto out;
1326 if (ret > 0) {
1327 if (path->slots[0] == 0)
1328 goto out;
1329 path->slots[0]--;
1330 }
1331 if (ret != 0)
1332 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1333
1334 if (key.type != key_type || key.objectid != dirid) {
1335 ret = 1;
1336 goto next;
1337 }
1338 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
1339 struct btrfs_dir_log_item);
1340 found_end = btrfs_dir_log_end(path->nodes[0], item);
1341
1342 if (*start_ret >= key.offset && *start_ret <= found_end) {
1343 ret = 0;
1344 *start_ret = key.offset;
1345 *end_ret = found_end;
1346 goto out;
1347 }
1348 ret = 1;
1349next:
1350 /* check the next slot in the tree to see if it is a valid item */
1351 nritems = btrfs_header_nritems(path->nodes[0]);
1352 if (path->slots[0] >= nritems) {
1353 ret = btrfs_next_leaf(root, path);
1354 if (ret)
1355 goto out;
1356 } else {
1357 path->slots[0]++;
1358 }
1359
1360 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1361
1362 if (key.type != key_type || key.objectid != dirid) {
1363 ret = 1;
1364 goto out;
1365 }
1366 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
1367 struct btrfs_dir_log_item);
1368 found_end = btrfs_dir_log_end(path->nodes[0], item);
1369 *start_ret = key.offset;
1370 *end_ret = found_end;
1371 ret = 0;
1372out:
1373 btrfs_release_path(root, path);
1374 return ret;
1375}
1376
1377/*
1378 * this looks for a given directory item in the log. If the directory
1379 * item is not in the log, the item is removed and the inode it points
1380 * to is unlinked
1381 */
1382static noinline int check_item_in_log(struct btrfs_trans_handle *trans,
1383 struct btrfs_root *root,
1384 struct btrfs_root *log,
1385 struct btrfs_path *path,
1386 struct btrfs_path *log_path,
1387 struct inode *dir,
1388 struct btrfs_key *dir_key)
1389{
1390 int ret;
1391 struct extent_buffer *eb;
1392 int slot;
1393 u32 item_size;
1394 struct btrfs_dir_item *di;
1395 struct btrfs_dir_item *log_di;
1396 int name_len;
1397 unsigned long ptr;
1398 unsigned long ptr_end;
1399 char *name;
1400 struct inode *inode;
1401 struct btrfs_key location;
1402
1403again:
1404 eb = path->nodes[0];
1405 slot = path->slots[0];
1406 item_size = btrfs_item_size_nr(eb, slot);
1407 ptr = btrfs_item_ptr_offset(eb, slot);
1408 ptr_end = ptr + item_size;
1409 while (ptr < ptr_end) {
1410 di = (struct btrfs_dir_item *)ptr;
1411 name_len = btrfs_dir_name_len(eb, di);
1412 name = kmalloc(name_len, GFP_NOFS);
1413 if (!name) {
1414 ret = -ENOMEM;
1415 goto out;
1416 }
1417 read_extent_buffer(eb, name, (unsigned long)(di + 1),
1418 name_len);
1419 log_di = NULL;
1420 if (dir_key->type == BTRFS_DIR_ITEM_KEY) {
1421 log_di = btrfs_lookup_dir_item(trans, log, log_path,
1422 dir_key->objectid,
1423 name, name_len, 0);
1424 } else if (dir_key->type == BTRFS_DIR_INDEX_KEY) {
1425 log_di = btrfs_lookup_dir_index_item(trans, log,
1426 log_path,
1427 dir_key->objectid,
1428 dir_key->offset,
1429 name, name_len, 0);
1430 }
1431 if (!log_di || IS_ERR(log_di)) {
1432 btrfs_dir_item_key_to_cpu(eb, di, &location);
1433 btrfs_release_path(root, path);
1434 btrfs_release_path(log, log_path);
1435 inode = read_one_inode(root, location.objectid);
1436 BUG_ON(!inode);
1437
1438 ret = link_to_fixup_dir(trans, root,
1439 path, location.objectid);
1440 BUG_ON(ret);
1441 btrfs_inc_nlink(inode);
1442 ret = btrfs_unlink_inode(trans, root, dir, inode,
1443 name, name_len);
1444 BUG_ON(ret);
1445 kfree(name);
1446 iput(inode);
1447
1448 /* there might still be more names under this key
1449 * check and repeat if required
1450 */
1451 ret = btrfs_search_slot(NULL, root, dir_key, path,
1452 0, 0);
1453 if (ret == 0)
1454 goto again;
1455 ret = 0;
1456 goto out;
1457 }
1458 btrfs_release_path(log, log_path);
1459 kfree(name);
1460
1461 ptr = (unsigned long)(di + 1);
1462 ptr += name_len;
1463 }
1464 ret = 0;
1465out:
1466 btrfs_release_path(root, path);
1467 btrfs_release_path(log, log_path);
1468 return ret;
1469}
1470
1471/*
1472 * deletion replay happens before we copy any new directory items
1473 * out of the log or out of backreferences from inodes. It
1474 * scans the log to find ranges of keys that log is authoritative for,
1475 * and then scans the directory to find items in those ranges that are
1476 * not present in the log.
1477 *
1478 * Anything we don't find in the log is unlinked and removed from the
1479 * directory.
1480 */
1481static noinline int replay_dir_deletes(struct btrfs_trans_handle *trans,
1482 struct btrfs_root *root,
1483 struct btrfs_root *log,
1484 struct btrfs_path *path,
1485 u64 dirid)
1486{
1487 u64 range_start;
1488 u64 range_end;
1489 int key_type = BTRFS_DIR_LOG_ITEM_KEY;
1490 int ret = 0;
1491 struct btrfs_key dir_key;
1492 struct btrfs_key found_key;
1493 struct btrfs_path *log_path;
1494 struct inode *dir;
1495
1496 dir_key.objectid = dirid;
1497 dir_key.type = BTRFS_DIR_ITEM_KEY;
1498 log_path = btrfs_alloc_path();
1499 if (!log_path)
1500 return -ENOMEM;
1501
1502 dir = read_one_inode(root, dirid);
1503 /* it isn't an error if the inode isn't there, that can happen
1504 * because we replay the deletes before we copy in the inode item
1505 * from the log
1506 */
1507 if (!dir) {
1508 btrfs_free_path(log_path);
1509 return 0;
1510 }
1511again:
1512 range_start = 0;
1513 range_end = 0;
1514 while (1) {
1515 ret = find_dir_range(log, path, dirid, key_type,
1516 &range_start, &range_end);
1517 if (ret != 0)
1518 break;
1519
1520 dir_key.offset = range_start;
1521 while (1) {
1522 int nritems;
1523 ret = btrfs_search_slot(NULL, root, &dir_key, path,
1524 0, 0);
1525 if (ret < 0)
1526 goto out;
1527
1528 nritems = btrfs_header_nritems(path->nodes[0]);
1529 if (path->slots[0] >= nritems) {
1530 ret = btrfs_next_leaf(root, path);
1531 if (ret)
1532 break;
1533 }
1534 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1535 path->slots[0]);
1536 if (found_key.objectid != dirid ||
1537 found_key.type != dir_key.type)
1538 goto next_type;
1539
1540 if (found_key.offset > range_end)
1541 break;
1542
1543 ret = check_item_in_log(trans, root, log, path,
1544 log_path, dir, &found_key);
1545 BUG_ON(ret);
1546 if (found_key.offset == (u64)-1)
1547 break;
1548 dir_key.offset = found_key.offset + 1;
1549 }
1550 btrfs_release_path(root, path);
1551 if (range_end == (u64)-1)
1552 break;
1553 range_start = range_end + 1;
1554 }
1555
1556next_type:
1557 ret = 0;
1558 if (key_type == BTRFS_DIR_LOG_ITEM_KEY) {
1559 key_type = BTRFS_DIR_LOG_INDEX_KEY;
1560 dir_key.type = BTRFS_DIR_INDEX_KEY;
1561 btrfs_release_path(root, path);
1562 goto again;
1563 }
1564out:
1565 btrfs_release_path(root, path);
1566 btrfs_free_path(log_path);
1567 iput(dir);
1568 return ret;
1569}
1570
1571/*
1572 * the process_func used to replay items from the log tree. This
1573 * gets called in two different stages. The first stage just looks
1574 * for inodes and makes sure they are all copied into the subvolume.
1575 *
1576 * The second stage copies all the other item types from the log into
1577 * the subvolume. The two stage approach is slower, but gets rid of
1578 * lots of complexity around inodes referencing other inodes that exist
1579 * only in the log (references come from either directory items or inode
1580 * back refs).
1581 */
1582static int replay_one_buffer(struct btrfs_root *log, struct extent_buffer *eb,
1583 struct walk_control *wc, u64 gen)
1584{
1585 int nritems;
1586 struct btrfs_path *path;
1587 struct btrfs_root *root = wc->replay_dest;
1588 struct btrfs_key key;
1589 u32 item_size;
1590 int level;
1591 int i;
1592 int ret;
1593
1594 btrfs_read_buffer(eb, gen);
1595
1596 level = btrfs_header_level(eb);
1597
1598 if (level != 0)
1599 return 0;
1600
1601 path = btrfs_alloc_path();
1602 BUG_ON(!path);
1603
1604 nritems = btrfs_header_nritems(eb);
1605 for (i = 0; i < nritems; i++) {
1606 btrfs_item_key_to_cpu(eb, &key, i);
1607 item_size = btrfs_item_size_nr(eb, i);
1608
1609 /* inode keys are done during the first stage */
1610 if (key.type == BTRFS_INODE_ITEM_KEY &&
1611 wc->stage == LOG_WALK_REPLAY_INODES) {
1612 struct inode *inode;
1613 struct btrfs_inode_item *inode_item;
1614 u32 mode;
1615
1616 inode_item = btrfs_item_ptr(eb, i,
1617 struct btrfs_inode_item);
1618 mode = btrfs_inode_mode(eb, inode_item);
1619 if (S_ISDIR(mode)) {
1620 ret = replay_dir_deletes(wc->trans,
1621 root, log, path, key.objectid);
1622 BUG_ON(ret);
1623 }
1624 ret = overwrite_item(wc->trans, root, path,
1625 eb, i, &key);
1626 BUG_ON(ret);
1627
1628 /* for regular files, truncate away
1629 * extents past the new EOF
1630 */
1631 if (S_ISREG(mode)) {
1632 inode = read_one_inode(root,
1633 key.objectid);
1634 BUG_ON(!inode);
1635
1636 ret = btrfs_truncate_inode_items(wc->trans,
1637 root, inode, inode->i_size,
1638 BTRFS_EXTENT_DATA_KEY);
1639 BUG_ON(ret);
1640 iput(inode);
1641 }
1642 ret = link_to_fixup_dir(wc->trans, root,
1643 path, key.objectid);
1644 BUG_ON(ret);
1645 }
1646 if (wc->stage < LOG_WALK_REPLAY_ALL)
1647 continue;
1648
1649 /* these keys are simply copied */
1650 if (key.type == BTRFS_XATTR_ITEM_KEY) {
1651 ret = overwrite_item(wc->trans, root, path,
1652 eb, i, &key);
1653 BUG_ON(ret);
1654 } else if (key.type == BTRFS_INODE_REF_KEY) {
1655 ret = add_inode_ref(wc->trans, root, log, path,
1656 eb, i, &key);
1657 BUG_ON(ret && ret != -ENOENT);
1658 } else if (key.type == BTRFS_EXTENT_DATA_KEY) {
1659 ret = replay_one_extent(wc->trans, root, path,
1660 eb, i, &key);
1661 BUG_ON(ret);
1662 } else if (key.type == BTRFS_EXTENT_CSUM_KEY) {
1663 ret = replay_one_csum(wc->trans, root, path,
1664 eb, i, &key);
1665 BUG_ON(ret);
1666 } else if (key.type == BTRFS_DIR_ITEM_KEY ||
1667 key.type == BTRFS_DIR_INDEX_KEY) {
1668 ret = replay_one_dir_item(wc->trans, root, path,
1669 eb, i, &key);
1670 BUG_ON(ret);
1671 }
1672 }
1673 btrfs_free_path(path);
1674 return 0;
1675}
1676
1677static noinline int walk_down_log_tree(struct btrfs_trans_handle *trans,
1678 struct btrfs_root *root,
1679 struct btrfs_path *path, int *level,
1680 struct walk_control *wc)
1681{
1682 u64 root_owner;
1683 u64 root_gen;
1684 u64 bytenr;
1685 u64 ptr_gen;
1686 struct extent_buffer *next;
1687 struct extent_buffer *cur;
1688 struct extent_buffer *parent;
1689 u32 blocksize;
1690 int ret = 0;
1691
1692 WARN_ON(*level < 0);
1693 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1694
1695 while (*level > 0) {
1696 WARN_ON(*level < 0);
1697 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1698 cur = path->nodes[*level];
1699
1700 if (btrfs_header_level(cur) != *level)
1701 WARN_ON(1);
1702
1703 if (path->slots[*level] >=
1704 btrfs_header_nritems(cur))
1705 break;
1706
1707 bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
1708 ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
1709 blocksize = btrfs_level_size(root, *level - 1);
1710
1711 parent = path->nodes[*level];
1712 root_owner = btrfs_header_owner(parent);
1713 root_gen = btrfs_header_generation(parent);
1714
1715 next = btrfs_find_create_tree_block(root, bytenr, blocksize);
1716
1717 wc->process_func(root, next, wc, ptr_gen);
1718
1719 if (*level == 1) {
1720 path->slots[*level]++;
1721 if (wc->free) {
1722 btrfs_read_buffer(next, ptr_gen);
1723
1724 btrfs_tree_lock(next);
1725 clean_tree_block(trans, root, next);
1726 btrfs_wait_tree_block_writeback(next);
1727 btrfs_tree_unlock(next);
1728
1729 ret = btrfs_drop_leaf_ref(trans, root, next);
1730 BUG_ON(ret);
1731
1732 WARN_ON(root_owner !=
1733 BTRFS_TREE_LOG_OBJECTID);
1734 ret = btrfs_free_reserved_extent(root,
1735 bytenr, blocksize);
1736 BUG_ON(ret);
1737 }
1738 free_extent_buffer(next);
1739 continue;
1740 }
1741 btrfs_read_buffer(next, ptr_gen);
1742
1743 WARN_ON(*level <= 0);
1744 if (path->nodes[*level-1])
1745 free_extent_buffer(path->nodes[*level-1]);
1746 path->nodes[*level-1] = next;
1747 *level = btrfs_header_level(next);
1748 path->slots[*level] = 0;
1749 cond_resched();
1750 }
1751 WARN_ON(*level < 0);
1752 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1753
1754 if (path->nodes[*level] == root->node)
1755 parent = path->nodes[*level];
1756 else
1757 parent = path->nodes[*level + 1];
1758
1759 bytenr = path->nodes[*level]->start;
1760
1761 blocksize = btrfs_level_size(root, *level);
1762 root_owner = btrfs_header_owner(parent);
1763 root_gen = btrfs_header_generation(parent);
1764
1765 wc->process_func(root, path->nodes[*level], wc,
1766 btrfs_header_generation(path->nodes[*level]));
1767
1768 if (wc->free) {
1769 next = path->nodes[*level];
1770 btrfs_tree_lock(next);
1771 clean_tree_block(trans, root, next);
1772 btrfs_wait_tree_block_writeback(next);
1773 btrfs_tree_unlock(next);
1774
1775 if (*level == 0) {
1776 ret = btrfs_drop_leaf_ref(trans, root, next);
1777 BUG_ON(ret);
1778 }
1779 WARN_ON(root_owner != BTRFS_TREE_LOG_OBJECTID);
1780 ret = btrfs_free_reserved_extent(root, bytenr, blocksize);
1781 BUG_ON(ret);
1782 }
1783 free_extent_buffer(path->nodes[*level]);
1784 path->nodes[*level] = NULL;
1785 *level += 1;
1786
1787 cond_resched();
1788 return 0;
1789}
1790
1791static noinline int walk_up_log_tree(struct btrfs_trans_handle *trans,
1792 struct btrfs_root *root,
1793 struct btrfs_path *path, int *level,
1794 struct walk_control *wc)
1795{
1796 u64 root_owner;
1797 u64 root_gen;
1798 int i;
1799 int slot;
1800 int ret;
1801
1802 for (i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
1803 slot = path->slots[i];
1804 if (slot < btrfs_header_nritems(path->nodes[i]) - 1) {
1805 struct extent_buffer *node;
1806 node = path->nodes[i];
1807 path->slots[i]++;
1808 *level = i;
1809 WARN_ON(*level == 0);
1810 return 0;
1811 } else {
1812 struct extent_buffer *parent;
1813 if (path->nodes[*level] == root->node)
1814 parent = path->nodes[*level];
1815 else
1816 parent = path->nodes[*level + 1];
1817
1818 root_owner = btrfs_header_owner(parent);
1819 root_gen = btrfs_header_generation(parent);
1820 wc->process_func(root, path->nodes[*level], wc,
1821 btrfs_header_generation(path->nodes[*level]));
1822 if (wc->free) {
1823 struct extent_buffer *next;
1824
1825 next = path->nodes[*level];
1826
1827 btrfs_tree_lock(next);
1828 clean_tree_block(trans, root, next);
1829 btrfs_wait_tree_block_writeback(next);
1830 btrfs_tree_unlock(next);
1831
1832 if (*level == 0) {
1833 ret = btrfs_drop_leaf_ref(trans, root,
1834 next);
1835 BUG_ON(ret);
1836 }
1837
1838 WARN_ON(root_owner != BTRFS_TREE_LOG_OBJECTID);
1839 ret = btrfs_free_reserved_extent(root,
1840 path->nodes[*level]->start,
1841 path->nodes[*level]->len);
1842 BUG_ON(ret);
1843 }
1844 free_extent_buffer(path->nodes[*level]);
1845 path->nodes[*level] = NULL;
1846 *level = i + 1;
1847 }
1848 }
1849 return 1;
1850}
1851
1852/*
1853 * drop the reference count on the tree rooted at 'snap'. This traverses
1854 * the tree freeing any blocks that have a ref count of zero after being
1855 * decremented.
1856 */
1857static int walk_log_tree(struct btrfs_trans_handle *trans,
1858 struct btrfs_root *log, struct walk_control *wc)
1859{
1860 int ret = 0;
1861 int wret;
1862 int level;
1863 struct btrfs_path *path;
1864 int i;
1865 int orig_level;
1866
1867 path = btrfs_alloc_path();
1868 BUG_ON(!path);
1869
1870 level = btrfs_header_level(log->node);
1871 orig_level = level;
1872 path->nodes[level] = log->node;
1873 extent_buffer_get(log->node);
1874 path->slots[level] = 0;
1875
1876 while (1) {
1877 wret = walk_down_log_tree(trans, log, path, &level, wc);
1878 if (wret > 0)
1879 break;
1880 if (wret < 0)
1881 ret = wret;
1882
1883 wret = walk_up_log_tree(trans, log, path, &level, wc);
1884 if (wret > 0)
1885 break;
1886 if (wret < 0)
1887 ret = wret;
1888 }
1889
1890 /* was the root node processed? if not, catch it here */
1891 if (path->nodes[orig_level]) {
1892 wc->process_func(log, path->nodes[orig_level], wc,
1893 btrfs_header_generation(path->nodes[orig_level]));
1894 if (wc->free) {
1895 struct extent_buffer *next;
1896
1897 next = path->nodes[orig_level];
1898
1899 btrfs_tree_lock(next);
1900 clean_tree_block(trans, log, next);
1901 btrfs_wait_tree_block_writeback(next);
1902 btrfs_tree_unlock(next);
1903
1904 if (orig_level == 0) {
1905 ret = btrfs_drop_leaf_ref(trans, log,
1906 next);
1907 BUG_ON(ret);
1908 }
1909 WARN_ON(log->root_key.objectid !=
1910 BTRFS_TREE_LOG_OBJECTID);
1911 ret = btrfs_free_reserved_extent(log, next->start,
1912 next->len);
1913 BUG_ON(ret);
1914 }
1915 }
1916
1917 for (i = 0; i <= orig_level; i++) {
1918 if (path->nodes[i]) {
1919 free_extent_buffer(path->nodes[i]);
1920 path->nodes[i] = NULL;
1921 }
1922 }
1923 btrfs_free_path(path);
1924 if (wc->free)
1925 free_extent_buffer(log->node);
1926 return ret;
1927}
1928
1929static int wait_log_commit(struct btrfs_root *log)
1930{
1931 DEFINE_WAIT(wait);
1932 u64 transid = log->fs_info->tree_log_transid;
1933
1934 do {
1935 prepare_to_wait(&log->fs_info->tree_log_wait, &wait,
1936 TASK_UNINTERRUPTIBLE);
1937 mutex_unlock(&log->fs_info->tree_log_mutex);
1938 if (atomic_read(&log->fs_info->tree_log_commit))
1939 schedule();
1940 finish_wait(&log->fs_info->tree_log_wait, &wait);
1941 mutex_lock(&log->fs_info->tree_log_mutex);
1942 } while (transid == log->fs_info->tree_log_transid &&
1943 atomic_read(&log->fs_info->tree_log_commit));
1944 return 0;
1945}
1946
1947/*
1948 * btrfs_sync_log does sends a given tree log down to the disk and
1949 * updates the super blocks to record it. When this call is done,
1950 * you know that any inodes previously logged are safely on disk
1951 */
1952int btrfs_sync_log(struct btrfs_trans_handle *trans,
1953 struct btrfs_root *root)
1954{
1955 int ret;
1956 unsigned long batch;
1957 struct btrfs_root *log = root->log_root;
1958
1959 mutex_lock(&log->fs_info->tree_log_mutex);
1960 if (atomic_read(&log->fs_info->tree_log_commit)) {
1961 wait_log_commit(log);
1962 goto out;
1963 }
1964 atomic_set(&log->fs_info->tree_log_commit, 1);
1965
1966 while (1) {
1967 batch = log->fs_info->tree_log_batch;
1968 mutex_unlock(&log->fs_info->tree_log_mutex);
1969 schedule_timeout_uninterruptible(1);
1970 mutex_lock(&log->fs_info->tree_log_mutex);
1971
1972 while (atomic_read(&log->fs_info->tree_log_writers)) {
1973 DEFINE_WAIT(wait);
1974 prepare_to_wait(&log->fs_info->tree_log_wait, &wait,
1975 TASK_UNINTERRUPTIBLE);
1976 mutex_unlock(&log->fs_info->tree_log_mutex);
1977 if (atomic_read(&log->fs_info->tree_log_writers))
1978 schedule();
1979 mutex_lock(&log->fs_info->tree_log_mutex);
1980 finish_wait(&log->fs_info->tree_log_wait, &wait);
1981 }
1982 if (batch == log->fs_info->tree_log_batch)
1983 break;
1984 }
1985
1986 ret = btrfs_write_and_wait_marked_extents(log, &log->dirty_log_pages);
1987 BUG_ON(ret);
1988 ret = btrfs_write_and_wait_marked_extents(root->fs_info->log_root_tree,
1989 &root->fs_info->log_root_tree->dirty_log_pages);
1990 BUG_ON(ret);
1991
1992 btrfs_set_super_log_root(&root->fs_info->super_for_commit,
1993 log->fs_info->log_root_tree->node->start);
1994 btrfs_set_super_log_root_level(&root->fs_info->super_for_commit,
1995 btrfs_header_level(log->fs_info->log_root_tree->node));
1996
1997 write_ctree_super(trans, log->fs_info->tree_root, 2);
1998 log->fs_info->tree_log_transid++;
1999 log->fs_info->tree_log_batch = 0;
2000 atomic_set(&log->fs_info->tree_log_commit, 0);
2001 smp_mb();
2002 if (waitqueue_active(&log->fs_info->tree_log_wait))
2003 wake_up(&log->fs_info->tree_log_wait);
2004out:
2005 mutex_unlock(&log->fs_info->tree_log_mutex);
2006 return 0;
2007}
2008
2009/* * free all the extents used by the tree log. This should be called
2010 * at commit time of the full transaction
2011 */
2012int btrfs_free_log(struct btrfs_trans_handle *trans, struct btrfs_root *root)
2013{
2014 int ret;
2015 struct btrfs_root *log;
2016 struct key;
2017 u64 start;
2018 u64 end;
2019 struct walk_control wc = {
2020 .free = 1,
2021 .process_func = process_one_buffer
2022 };
2023
2024 if (!root->log_root)
2025 return 0;
2026
2027 log = root->log_root;
2028 ret = walk_log_tree(trans, log, &wc);
2029 BUG_ON(ret);
2030
2031 while (1) {
2032 ret = find_first_extent_bit(&log->dirty_log_pages,
2033 0, &start, &end, EXTENT_DIRTY);
2034 if (ret)
2035 break;
2036
2037 clear_extent_dirty(&log->dirty_log_pages,
2038 start, end, GFP_NOFS);
2039 }
2040
2041 log = root->log_root;
2042 ret = btrfs_del_root(trans, root->fs_info->log_root_tree,
2043 &log->root_key);
2044 BUG_ON(ret);
2045 root->log_root = NULL;
2046 kfree(root->log_root);
2047 return 0;
2048}
2049
2050/*
2051 * helper function to update the item for a given subvolumes log root
2052 * in the tree of log roots
2053 */
2054static int update_log_root(struct btrfs_trans_handle *trans,
2055 struct btrfs_root *log)
2056{
2057 u64 bytenr = btrfs_root_bytenr(&log->root_item);
2058 int ret;
2059
2060 if (log->node->start == bytenr)
2061 return 0;
2062
2063 btrfs_set_root_bytenr(&log->root_item, log->node->start);
2064 btrfs_set_root_generation(&log->root_item, trans->transid);
2065 btrfs_set_root_level(&log->root_item, btrfs_header_level(log->node));
2066 ret = btrfs_update_root(trans, log->fs_info->log_root_tree,
2067 &log->root_key, &log->root_item);
2068 BUG_ON(ret);
2069 return ret;
2070}
2071
2072/*
2073 * If both a file and directory are logged, and unlinks or renames are
2074 * mixed in, we have a few interesting corners:
2075 *
2076 * create file X in dir Y
2077 * link file X to X.link in dir Y
2078 * fsync file X
2079 * unlink file X but leave X.link
2080 * fsync dir Y
2081 *
2082 * After a crash we would expect only X.link to exist. But file X
2083 * didn't get fsync'd again so the log has back refs for X and X.link.
2084 *
2085 * We solve this by removing directory entries and inode backrefs from the
2086 * log when a file that was logged in the current transaction is
2087 * unlinked. Any later fsync will include the updated log entries, and
2088 * we'll be able to reconstruct the proper directory items from backrefs.
2089 *
2090 * This optimizations allows us to avoid relogging the entire inode
2091 * or the entire directory.
2092 */
2093int btrfs_del_dir_entries_in_log(struct btrfs_trans_handle *trans,
2094 struct btrfs_root *root,
2095 const char *name, int name_len,
2096 struct inode *dir, u64 index)
2097{
2098 struct btrfs_root *log;
2099 struct btrfs_dir_item *di;
2100 struct btrfs_path *path;
2101 int ret;
2102 int bytes_del = 0;
2103
2104 if (BTRFS_I(dir)->logged_trans < trans->transid)
2105 return 0;
2106
2107 ret = join_running_log_trans(root);
2108 if (ret)
2109 return 0;
2110
2111 mutex_lock(&BTRFS_I(dir)->log_mutex);
2112
2113 log = root->log_root;
2114 path = btrfs_alloc_path();
2115 di = btrfs_lookup_dir_item(trans, log, path, dir->i_ino,
2116 name, name_len, -1);
2117 if (di && !IS_ERR(di)) {
2118 ret = btrfs_delete_one_dir_name(trans, log, path, di);
2119 bytes_del += name_len;
2120 BUG_ON(ret);
2121 }
2122 btrfs_release_path(log, path);
2123 di = btrfs_lookup_dir_index_item(trans, log, path, dir->i_ino,
2124 index, name, name_len, -1);
2125 if (di && !IS_ERR(di)) {
2126 ret = btrfs_delete_one_dir_name(trans, log, path, di);
2127 bytes_del += name_len;
2128 BUG_ON(ret);
2129 }
2130
2131 /* update the directory size in the log to reflect the names
2132 * we have removed
2133 */
2134 if (bytes_del) {
2135 struct btrfs_key key;
2136
2137 key.objectid = dir->i_ino;
2138 key.offset = 0;
2139 key.type = BTRFS_INODE_ITEM_KEY;
2140 btrfs_release_path(log, path);
2141
2142 ret = btrfs_search_slot(trans, log, &key, path, 0, 1);
2143 if (ret == 0) {
2144 struct btrfs_inode_item *item;
2145 u64 i_size;
2146
2147 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2148 struct btrfs_inode_item);
2149 i_size = btrfs_inode_size(path->nodes[0], item);
2150 if (i_size > bytes_del)
2151 i_size -= bytes_del;
2152 else
2153 i_size = 0;
2154 btrfs_set_inode_size(path->nodes[0], item, i_size);
2155 btrfs_mark_buffer_dirty(path->nodes[0]);
2156 } else
2157 ret = 0;
2158 btrfs_release_path(log, path);
2159 }
2160
2161 btrfs_free_path(path);
2162 mutex_unlock(&BTRFS_I(dir)->log_mutex);
2163 end_log_trans(root);
2164
2165 return 0;
2166}
2167
2168/* see comments for btrfs_del_dir_entries_in_log */
2169int btrfs_del_inode_ref_in_log(struct btrfs_trans_handle *trans,
2170 struct btrfs_root *root,
2171 const char *name, int name_len,
2172 struct inode *inode, u64 dirid)
2173{
2174 struct btrfs_root *log;
2175 u64 index;
2176 int ret;
2177
2178 if (BTRFS_I(inode)->logged_trans < trans->transid)
2179 return 0;
2180
2181 ret = join_running_log_trans(root);
2182 if (ret)
2183 return 0;
2184 log = root->log_root;
2185 mutex_lock(&BTRFS_I(inode)->log_mutex);
2186
2187 ret = btrfs_del_inode_ref(trans, log, name, name_len, inode->i_ino,
2188 dirid, &index);
2189 mutex_unlock(&BTRFS_I(inode)->log_mutex);
2190 end_log_trans(root);
2191
2192 return ret;
2193}
2194
2195/*
2196 * creates a range item in the log for 'dirid'. first_offset and
2197 * last_offset tell us which parts of the key space the log should
2198 * be considered authoritative for.
2199 */
2200static noinline int insert_dir_log_key(struct btrfs_trans_handle *trans,
2201 struct btrfs_root *log,
2202 struct btrfs_path *path,
2203 int key_type, u64 dirid,
2204 u64 first_offset, u64 last_offset)
2205{
2206 int ret;
2207 struct btrfs_key key;
2208 struct btrfs_dir_log_item *item;
2209
2210 key.objectid = dirid;
2211 key.offset = first_offset;
2212 if (key_type == BTRFS_DIR_ITEM_KEY)
2213 key.type = BTRFS_DIR_LOG_ITEM_KEY;
2214 else
2215 key.type = BTRFS_DIR_LOG_INDEX_KEY;
2216 ret = btrfs_insert_empty_item(trans, log, path, &key, sizeof(*item));
2217 BUG_ON(ret);
2218
2219 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2220 struct btrfs_dir_log_item);
2221 btrfs_set_dir_log_end(path->nodes[0], item, last_offset);
2222 btrfs_mark_buffer_dirty(path->nodes[0]);
2223 btrfs_release_path(log, path);
2224 return 0;
2225}
2226
2227/*
2228 * log all the items included in the current transaction for a given
2229 * directory. This also creates the range items in the log tree required
2230 * to replay anything deleted before the fsync
2231 */
2232static noinline int log_dir_items(struct btrfs_trans_handle *trans,
2233 struct btrfs_root *root, struct inode *inode,
2234 struct btrfs_path *path,
2235 struct btrfs_path *dst_path, int key_type,
2236 u64 min_offset, u64 *last_offset_ret)
2237{
2238 struct btrfs_key min_key;
2239 struct btrfs_key max_key;
2240 struct btrfs_root *log = root->log_root;
2241 struct extent_buffer *src;
2242 int ret;
2243 int i;
2244 int nritems;
2245 u64 first_offset = min_offset;
2246 u64 last_offset = (u64)-1;
2247
2248 log = root->log_root;
2249 max_key.objectid = inode->i_ino;
2250 max_key.offset = (u64)-1;
2251 max_key.type = key_type;
2252
2253 min_key.objectid = inode->i_ino;
2254 min_key.type = key_type;
2255 min_key.offset = min_offset;
2256
2257 path->keep_locks = 1;
2258
2259 ret = btrfs_search_forward(root, &min_key, &max_key,
2260 path, 0, trans->transid);
2261
2262 /*
2263 * we didn't find anything from this transaction, see if there
2264 * is anything at all
2265 */
2266 if (ret != 0 || min_key.objectid != inode->i_ino ||
2267 min_key.type != key_type) {
2268 min_key.objectid = inode->i_ino;
2269 min_key.type = key_type;
2270 min_key.offset = (u64)-1;
2271 btrfs_release_path(root, path);
2272 ret = btrfs_search_slot(NULL, root, &min_key, path, 0, 0);
2273 if (ret < 0) {
2274 btrfs_release_path(root, path);
2275 return ret;
2276 }
2277 ret = btrfs_previous_item(root, path, inode->i_ino, key_type);
2278
2279 /* if ret == 0 there are items for this type,
2280 * create a range to tell us the last key of this type.
2281 * otherwise, there are no items in this directory after
2282 * *min_offset, and we create a range to indicate that.
2283 */
2284 if (ret == 0) {
2285 struct btrfs_key tmp;
2286 btrfs_item_key_to_cpu(path->nodes[0], &tmp,
2287 path->slots[0]);
2288 if (key_type == tmp.type)
2289 first_offset = max(min_offset, tmp.offset) + 1;
2290 }
2291 goto done;
2292 }
2293
2294 /* go backward to find any previous key */
2295 ret = btrfs_previous_item(root, path, inode->i_ino, key_type);
2296 if (ret == 0) {
2297 struct btrfs_key tmp;
2298 btrfs_item_key_to_cpu(path->nodes[0], &tmp, path->slots[0]);
2299 if (key_type == tmp.type) {
2300 first_offset = tmp.offset;
2301 ret = overwrite_item(trans, log, dst_path,
2302 path->nodes[0], path->slots[0],
2303 &tmp);
2304 }
2305 }
2306 btrfs_release_path(root, path);
2307
2308 /* find the first key from this transaction again */
2309 ret = btrfs_search_slot(NULL, root, &min_key, path, 0, 0);
2310 if (ret != 0) {
2311 WARN_ON(1);
2312 goto done;
2313 }
2314
2315 /*
2316 * we have a block from this transaction, log every item in it
2317 * from our directory
2318 */
2319 while (1) {
2320 struct btrfs_key tmp;
2321 src = path->nodes[0];
2322 nritems = btrfs_header_nritems(src);
2323 for (i = path->slots[0]; i < nritems; i++) {
2324 btrfs_item_key_to_cpu(src, &min_key, i);
2325
2326 if (min_key.objectid != inode->i_ino ||
2327 min_key.type != key_type)
2328 goto done;
2329 ret = overwrite_item(trans, log, dst_path, src, i,
2330 &min_key);
2331 BUG_ON(ret);
2332 }
2333 path->slots[0] = nritems;
2334
2335 /*
2336 * look ahead to the next item and see if it is also
2337 * from this directory and from this transaction
2338 */
2339 ret = btrfs_next_leaf(root, path);
2340 if (ret == 1) {
2341 last_offset = (u64)-1;
2342 goto done;
2343 }
2344 btrfs_item_key_to_cpu(path->nodes[0], &tmp, path->slots[0]);
2345 if (tmp.objectid != inode->i_ino || tmp.type != key_type) {
2346 last_offset = (u64)-1;
2347 goto done;
2348 }
2349 if (btrfs_header_generation(path->nodes[0]) != trans->transid) {
2350 ret = overwrite_item(trans, log, dst_path,
2351 path->nodes[0], path->slots[0],
2352 &tmp);
2353
2354 BUG_ON(ret);
2355 last_offset = tmp.offset;
2356 goto done;
2357 }
2358 }
2359done:
2360 *last_offset_ret = last_offset;
2361 btrfs_release_path(root, path);
2362 btrfs_release_path(log, dst_path);
2363
2364 /* insert the log range keys to indicate where the log is valid */
2365 ret = insert_dir_log_key(trans, log, path, key_type, inode->i_ino,
2366 first_offset, last_offset);
2367 BUG_ON(ret);
2368 return 0;
2369}
2370
2371/*
2372 * logging directories is very similar to logging inodes, We find all the items
2373 * from the current transaction and write them to the log.
2374 *
2375 * The recovery code scans the directory in the subvolume, and if it finds a
2376 * key in the range logged that is not present in the log tree, then it means
2377 * that dir entry was unlinked during the transaction.
2378 *
2379 * In order for that scan to work, we must include one key smaller than
2380 * the smallest logged by this transaction and one key larger than the largest
2381 * key logged by this transaction.
2382 */
2383static noinline int log_directory_changes(struct btrfs_trans_handle *trans,
2384 struct btrfs_root *root, struct inode *inode,
2385 struct btrfs_path *path,
2386 struct btrfs_path *dst_path)
2387{
2388 u64 min_key;
2389 u64 max_key;
2390 int ret;
2391 int key_type = BTRFS_DIR_ITEM_KEY;
2392
2393again:
2394 min_key = 0;
2395 max_key = 0;
2396 while (1) {
2397 ret = log_dir_items(trans, root, inode, path,
2398 dst_path, key_type, min_key,
2399 &max_key);
2400 BUG_ON(ret);
2401 if (max_key == (u64)-1)
2402 break;
2403 min_key = max_key + 1;
2404 }
2405
2406 if (key_type == BTRFS_DIR_ITEM_KEY) {
2407 key_type = BTRFS_DIR_INDEX_KEY;
2408 goto again;
2409 }
2410 return 0;
2411}
2412
2413/*
2414 * a helper function to drop items from the log before we relog an
2415 * inode. max_key_type indicates the highest item type to remove.
2416 * This cannot be run for file data extents because it does not
2417 * free the extents they point to.
2418 */
2419static int drop_objectid_items(struct btrfs_trans_handle *trans,
2420 struct btrfs_root *log,
2421 struct btrfs_path *path,
2422 u64 objectid, int max_key_type)
2423{
2424 int ret;
2425 struct btrfs_key key;
2426 struct btrfs_key found_key;
2427
2428 key.objectid = objectid;
2429 key.type = max_key_type;
2430 key.offset = (u64)-1;
2431
2432 while (1) {
2433 ret = btrfs_search_slot(trans, log, &key, path, -1, 1);
2434
2435 if (ret != 1)
2436 break;
2437
2438 if (path->slots[0] == 0)
2439 break;
2440
2441 path->slots[0]--;
2442 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
2443 path->slots[0]);
2444
2445 if (found_key.objectid != objectid)
2446 break;
2447
2448 ret = btrfs_del_item(trans, log, path);
2449 BUG_ON(ret);
2450 btrfs_release_path(log, path);
2451 }
2452 btrfs_release_path(log, path);
2453 return 0;
2454}
2455
2456static noinline int copy_extent_csums(struct btrfs_trans_handle *trans,
2457 struct list_head *list,
2458 struct btrfs_root *root,
2459 u64 disk_bytenr, u64 len)
2460{
2461 struct btrfs_ordered_sum *sums;
2462 struct btrfs_sector_sum *sector_sum;
2463 int ret;
2464 struct btrfs_path *path;
2465 struct btrfs_csum_item *item = NULL;
2466 u64 end = disk_bytenr + len;
2467 u64 item_start_offset = 0;
2468 u64 item_last_offset = 0;
2469 u32 diff;
2470 u32 sum;
2471 u16 csum_size = btrfs_super_csum_size(&root->fs_info->super_copy);
2472
2473 sums = kzalloc(btrfs_ordered_sum_size(root, len), GFP_NOFS);
2474
2475 sector_sum = sums->sums;
2476 sums->bytenr = disk_bytenr;
2477 sums->len = len;
2478 list_add_tail(&sums->list, list);
2479
2480 path = btrfs_alloc_path();
2481 while (disk_bytenr < end) {
2482 if (!item || disk_bytenr < item_start_offset ||
2483 disk_bytenr >= item_last_offset) {
2484 struct btrfs_key found_key;
2485 u32 item_size;
2486
2487 if (item)
2488 btrfs_release_path(root, path);
2489 item = btrfs_lookup_csum(NULL, root, path,
2490 disk_bytenr, 0);
2491 if (IS_ERR(item)) {
2492 ret = PTR_ERR(item);
2493 if (ret == -ENOENT || ret == -EFBIG)
2494 ret = 0;
2495 sum = 0;
2496 printk(KERN_INFO "log no csum found for "
2497 "byte %llu\n",
2498 (unsigned long long)disk_bytenr);
2499 item = NULL;
2500 btrfs_release_path(root, path);
2501 goto found;
2502 }
2503 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
2504 path->slots[0]);
2505
2506 item_start_offset = found_key.offset;
2507 item_size = btrfs_item_size_nr(path->nodes[0],
2508 path->slots[0]);
2509 item_last_offset = item_start_offset +
2510 (item_size / csum_size) *
2511 root->sectorsize;
2512 item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2513 struct btrfs_csum_item);
2514 }
2515 /*
2516 * this byte range must be able to fit inside
2517 * a single leaf so it will also fit inside a u32
2518 */
2519 diff = disk_bytenr - item_start_offset;
2520 diff = diff / root->sectorsize;
2521 diff = diff * csum_size;
2522
2523 read_extent_buffer(path->nodes[0], &sum,
2524 ((unsigned long)item) + diff,
2525 csum_size);
2526found:
2527 sector_sum->bytenr = disk_bytenr;
2528 sector_sum->sum = sum;
2529 disk_bytenr += root->sectorsize;
2530 sector_sum++;
2531 }
2532 btrfs_free_path(path);
2533 return 0;
2534}
2535
2536static noinline int copy_items(struct btrfs_trans_handle *trans,
2537 struct btrfs_root *log,
2538 struct btrfs_path *dst_path,
2539 struct extent_buffer *src,
2540 int start_slot, int nr, int inode_only)
2541{
2542 unsigned long src_offset;
2543 unsigned long dst_offset;
2544 struct btrfs_file_extent_item *extent;
2545 struct btrfs_inode_item *inode_item;
2546 int ret;
2547 struct btrfs_key *ins_keys;
2548 u32 *ins_sizes;
2549 char *ins_data;
2550 int i;
2551 struct list_head ordered_sums;
2552
2553 INIT_LIST_HEAD(&ordered_sums);
2554
2555 ins_data = kmalloc(nr * sizeof(struct btrfs_key) +
2556 nr * sizeof(u32), GFP_NOFS);
2557 ins_sizes = (u32 *)ins_data;
2558 ins_keys = (struct btrfs_key *)(ins_data + nr * sizeof(u32));
2559
2560 for (i = 0; i < nr; i++) {
2561 ins_sizes[i] = btrfs_item_size_nr(src, i + start_slot);
2562 btrfs_item_key_to_cpu(src, ins_keys + i, i + start_slot);
2563 }
2564 ret = btrfs_insert_empty_items(trans, log, dst_path,
2565 ins_keys, ins_sizes, nr);
2566 BUG_ON(ret);
2567
2568 for (i = 0; i < nr; i++) {
2569 dst_offset = btrfs_item_ptr_offset(dst_path->nodes[0],
2570 dst_path->slots[0]);
2571
2572 src_offset = btrfs_item_ptr_offset(src, start_slot + i);
2573
2574 copy_extent_buffer(dst_path->nodes[0], src, dst_offset,
2575 src_offset, ins_sizes[i]);
2576
2577 if (inode_only == LOG_INODE_EXISTS &&
2578 ins_keys[i].type == BTRFS_INODE_ITEM_KEY) {
2579 inode_item = btrfs_item_ptr(dst_path->nodes[0],
2580 dst_path->slots[0],
2581 struct btrfs_inode_item);
2582 btrfs_set_inode_size(dst_path->nodes[0], inode_item, 0);
2583
2584 /* set the generation to zero so the recover code
2585 * can tell the difference between an logging
2586 * just to say 'this inode exists' and a logging
2587 * to say 'update this inode with these values'
2588 */
2589 btrfs_set_inode_generation(dst_path->nodes[0],
2590 inode_item, 0);
2591 }
2592 /* take a reference on file data extents so that truncates
2593 * or deletes of this inode don't have to relog the inode
2594 * again
2595 */
2596 if (btrfs_key_type(ins_keys + i) == BTRFS_EXTENT_DATA_KEY) {
2597 int found_type;
2598 extent = btrfs_item_ptr(src, start_slot + i,
2599 struct btrfs_file_extent_item);
2600
2601 found_type = btrfs_file_extent_type(src, extent);
2602 if (found_type == BTRFS_FILE_EXTENT_REG ||
2603 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
2604 u64 ds = btrfs_file_extent_disk_bytenr(src,
2605 extent);
2606 u64 dl = btrfs_file_extent_disk_num_bytes(src,
2607 extent);
2608 u64 cs = btrfs_file_extent_offset(src, extent);
2609 u64 cl = btrfs_file_extent_num_bytes(src,
2610 extent);;
2611 if (btrfs_file_extent_compression(src,
2612 extent)) {
2613 cs = 0;
2614 cl = dl;
2615 }
2616 /* ds == 0 is a hole */
2617 if (ds != 0) {
2618 ret = btrfs_inc_extent_ref(trans, log,
2619 ds, dl,
2620 dst_path->nodes[0]->start,
2621 BTRFS_TREE_LOG_OBJECTID,
2622 trans->transid,
2623 ins_keys[i].objectid);
2624 BUG_ON(ret);
2625 ret = copy_extent_csums(trans,
2626 &ordered_sums,
2627 log->fs_info->csum_root,
2628 ds + cs, cl);
2629 BUG_ON(ret);
2630 }
2631 }
2632 }
2633 dst_path->slots[0]++;
2634 }
2635
2636 btrfs_mark_buffer_dirty(dst_path->nodes[0]);
2637 btrfs_release_path(log, dst_path);
2638 kfree(ins_data);
2639
2640 /*
2641 * we have to do this after the loop above to avoid changing the
2642 * log tree while trying to change the log tree.
2643 */
2644 while (!list_empty(&ordered_sums)) {
2645 struct btrfs_ordered_sum *sums = list_entry(ordered_sums.next,
2646 struct btrfs_ordered_sum,
2647 list);
2648 ret = btrfs_csum_file_blocks(trans, log, sums);
2649 BUG_ON(ret);
2650 list_del(&sums->list);
2651 kfree(sums);
2652 }
2653 return 0;
2654}
2655
2656/* log a single inode in the tree log.
2657 * At least one parent directory for this inode must exist in the tree
2658 * or be logged already.
2659 *
2660 * Any items from this inode changed by the current transaction are copied
2661 * to the log tree. An extra reference is taken on any extents in this
2662 * file, allowing us to avoid a whole pile of corner cases around logging
2663 * blocks that have been removed from the tree.
2664 *
2665 * See LOG_INODE_ALL and related defines for a description of what inode_only
2666 * does.
2667 *
2668 * This handles both files and directories.
2669 */
2670static int __btrfs_log_inode(struct btrfs_trans_handle *trans,
2671 struct btrfs_root *root, struct inode *inode,
2672 int inode_only)
2673{
2674 struct btrfs_path *path;
2675 struct btrfs_path *dst_path;
2676 struct btrfs_key min_key;
2677 struct btrfs_key max_key;
2678 struct btrfs_root *log = root->log_root;
2679 struct extent_buffer *src = NULL;
2680 u32 size;
2681 int ret;
2682 int nritems;
2683 int ins_start_slot = 0;
2684 int ins_nr;
2685
2686 log = root->log_root;
2687
2688 path = btrfs_alloc_path();
2689 dst_path = btrfs_alloc_path();
2690
2691 min_key.objectid = inode->i_ino;
2692 min_key.type = BTRFS_INODE_ITEM_KEY;
2693 min_key.offset = 0;
2694
2695 max_key.objectid = inode->i_ino;
2696 if (inode_only == LOG_INODE_EXISTS || S_ISDIR(inode->i_mode))
2697 max_key.type = BTRFS_XATTR_ITEM_KEY;
2698 else
2699 max_key.type = (u8)-1;
2700 max_key.offset = (u64)-1;
2701
2702 /*
2703 * if this inode has already been logged and we're in inode_only
2704 * mode, we don't want to delete the things that have already
2705 * been written to the log.
2706 *
2707 * But, if the inode has been through an inode_only log,
2708 * the logged_trans field is not set. This allows us to catch
2709 * any new names for this inode in the backrefs by logging it
2710 * again
2711 */
2712 if (inode_only == LOG_INODE_EXISTS &&
2713 BTRFS_I(inode)->logged_trans == trans->transid) {
2714 btrfs_free_path(path);
2715 btrfs_free_path(dst_path);
2716 goto out;
2717 }
2718 mutex_lock(&BTRFS_I(inode)->log_mutex);
2719
2720 /*
2721 * a brute force approach to making sure we get the most uptodate
2722 * copies of everything.
2723 */
2724 if (S_ISDIR(inode->i_mode)) {
2725 int max_key_type = BTRFS_DIR_LOG_INDEX_KEY;
2726
2727 if (inode_only == LOG_INODE_EXISTS)
2728 max_key_type = BTRFS_XATTR_ITEM_KEY;
2729 ret = drop_objectid_items(trans, log, path,
2730 inode->i_ino, max_key_type);
2731 } else {
2732 ret = btrfs_truncate_inode_items(trans, log, inode, 0, 0);
2733 }
2734 BUG_ON(ret);
2735 path->keep_locks = 1;
2736
2737 while (1) {
2738 ins_nr = 0;
2739 ret = btrfs_search_forward(root, &min_key, &max_key,
2740 path, 0, trans->transid);
2741 if (ret != 0)
2742 break;
2743again:
2744 /* note, ins_nr might be > 0 here, cleanup outside the loop */
2745 if (min_key.objectid != inode->i_ino)
2746 break;
2747 if (min_key.type > max_key.type)
2748 break;
2749
2750 src = path->nodes[0];
2751 size = btrfs_item_size_nr(src, path->slots[0]);
2752 if (ins_nr && ins_start_slot + ins_nr == path->slots[0]) {
2753 ins_nr++;
2754 goto next_slot;
2755 } else if (!ins_nr) {
2756 ins_start_slot = path->slots[0];
2757 ins_nr = 1;
2758 goto next_slot;
2759 }
2760
2761 ret = copy_items(trans, log, dst_path, src, ins_start_slot,
2762 ins_nr, inode_only);
2763 BUG_ON(ret);
2764 ins_nr = 1;
2765 ins_start_slot = path->slots[0];
2766next_slot:
2767
2768 nritems = btrfs_header_nritems(path->nodes[0]);
2769 path->slots[0]++;
2770 if (path->slots[0] < nritems) {
2771 btrfs_item_key_to_cpu(path->nodes[0], &min_key,
2772 path->slots[0]);
2773 goto again;
2774 }
2775 if (ins_nr) {
2776 ret = copy_items(trans, log, dst_path, src,
2777 ins_start_slot,
2778 ins_nr, inode_only);
2779 BUG_ON(ret);
2780 ins_nr = 0;
2781 }
2782 btrfs_release_path(root, path);
2783
2784 if (min_key.offset < (u64)-1)
2785 min_key.offset++;
2786 else if (min_key.type < (u8)-1)
2787 min_key.type++;
2788 else if (min_key.objectid < (u64)-1)
2789 min_key.objectid++;
2790 else
2791 break;
2792 }
2793 if (ins_nr) {
2794 ret = copy_items(trans, log, dst_path, src,
2795 ins_start_slot,
2796 ins_nr, inode_only);
2797 BUG_ON(ret);
2798 ins_nr = 0;
2799 }
2800 WARN_ON(ins_nr);
2801 if (inode_only == LOG_INODE_ALL && S_ISDIR(inode->i_mode)) {
2802 btrfs_release_path(root, path);
2803 btrfs_release_path(log, dst_path);
2804 BTRFS_I(inode)->log_dirty_trans = 0;
2805 ret = log_directory_changes(trans, root, inode, path, dst_path);
2806 BUG_ON(ret);
2807 }
2808 BTRFS_I(inode)->logged_trans = trans->transid;
2809 mutex_unlock(&BTRFS_I(inode)->log_mutex);
2810
2811 btrfs_free_path(path);
2812 btrfs_free_path(dst_path);
2813
2814 mutex_lock(&root->fs_info->tree_log_mutex);
2815 ret = update_log_root(trans, log);
2816 BUG_ON(ret);
2817 mutex_unlock(&root->fs_info->tree_log_mutex);
2818out:
2819 return 0;
2820}
2821
2822int btrfs_log_inode(struct btrfs_trans_handle *trans,
2823 struct btrfs_root *root, struct inode *inode,
2824 int inode_only)
2825{
2826 int ret;
2827
2828 start_log_trans(trans, root);
2829 ret = __btrfs_log_inode(trans, root, inode, inode_only);
2830 end_log_trans(root);
2831 return ret;
2832}
2833
2834/*
2835 * helper function around btrfs_log_inode to make sure newly created
2836 * parent directories also end up in the log. A minimal inode and backref
2837 * only logging is done of any parent directories that are older than
2838 * the last committed transaction
2839 */
2840int btrfs_log_dentry(struct btrfs_trans_handle *trans,
2841 struct btrfs_root *root, struct dentry *dentry)
2842{
2843 int inode_only = LOG_INODE_ALL;
2844 struct super_block *sb;
2845 int ret;
2846
2847 start_log_trans(trans, root);
2848 sb = dentry->d_inode->i_sb;
2849 while (1) {
2850 ret = __btrfs_log_inode(trans, root, dentry->d_inode,
2851 inode_only);
2852 BUG_ON(ret);
2853 inode_only = LOG_INODE_EXISTS;
2854
2855 dentry = dentry->d_parent;
2856 if (!dentry || !dentry->d_inode || sb != dentry->d_inode->i_sb)
2857 break;
2858
2859 if (BTRFS_I(dentry->d_inode)->generation <=
2860 root->fs_info->last_trans_committed)
2861 break;
2862 }
2863 end_log_trans(root);
2864 return 0;
2865}
2866
2867/*
2868 * it is not safe to log dentry if the chunk root has added new
2869 * chunks. This returns 0 if the dentry was logged, and 1 otherwise.
2870 * If this returns 1, you must commit the transaction to safely get your
2871 * data on disk.
2872 */
2873int btrfs_log_dentry_safe(struct btrfs_trans_handle *trans,
2874 struct btrfs_root *root, struct dentry *dentry)
2875{
2876 u64 gen;
2877 gen = root->fs_info->last_trans_new_blockgroup;
2878 if (gen > root->fs_info->last_trans_committed)
2879 return 1;
2880 else
2881 return btrfs_log_dentry(trans, root, dentry);
2882}
2883
2884/*
2885 * should be called during mount to recover any replay any log trees
2886 * from the FS
2887 */
2888int btrfs_recover_log_trees(struct btrfs_root *log_root_tree)
2889{
2890 int ret;
2891 struct btrfs_path *path;
2892 struct btrfs_trans_handle *trans;
2893 struct btrfs_key key;
2894 struct btrfs_key found_key;
2895 struct btrfs_key tmp_key;
2896 struct btrfs_root *log;
2897 struct btrfs_fs_info *fs_info = log_root_tree->fs_info;
2898 u64 highest_inode;
2899 struct walk_control wc = {
2900 .process_func = process_one_buffer,
2901 .stage = 0,
2902 };
2903
2904 fs_info->log_root_recovering = 1;
2905 path = btrfs_alloc_path();
2906 BUG_ON(!path);
2907
2908 trans = btrfs_start_transaction(fs_info->tree_root, 1);
2909
2910 wc.trans = trans;
2911 wc.pin = 1;
2912
2913 walk_log_tree(trans, log_root_tree, &wc);
2914
2915again:
2916 key.objectid = BTRFS_TREE_LOG_OBJECTID;
2917 key.offset = (u64)-1;
2918 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
2919
2920 while (1) {
2921 ret = btrfs_search_slot(NULL, log_root_tree, &key, path, 0, 0);
2922 if (ret < 0)
2923 break;
2924 if (ret > 0) {
2925 if (path->slots[0] == 0)
2926 break;
2927 path->slots[0]--;
2928 }
2929 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
2930 path->slots[0]);
2931 btrfs_release_path(log_root_tree, path);
2932 if (found_key.objectid != BTRFS_TREE_LOG_OBJECTID)
2933 break;
2934
2935 log = btrfs_read_fs_root_no_radix(log_root_tree,
2936 &found_key);
2937 BUG_ON(!log);
2938
2939
2940 tmp_key.objectid = found_key.offset;
2941 tmp_key.type = BTRFS_ROOT_ITEM_KEY;
2942 tmp_key.offset = (u64)-1;
2943
2944 wc.replay_dest = btrfs_read_fs_root_no_name(fs_info, &tmp_key);
2945
2946 BUG_ON(!wc.replay_dest);
2947
2948 btrfs_record_root_in_trans(wc.replay_dest);
2949 ret = walk_log_tree(trans, log, &wc);
2950 BUG_ON(ret);
2951
2952 if (wc.stage == LOG_WALK_REPLAY_ALL) {
2953 ret = fixup_inode_link_counts(trans, wc.replay_dest,
2954 path);
2955 BUG_ON(ret);
2956 }
2957 ret = btrfs_find_highest_inode(wc.replay_dest, &highest_inode);
2958 if (ret == 0) {
2959 wc.replay_dest->highest_inode = highest_inode;
2960 wc.replay_dest->last_inode_alloc = highest_inode;
2961 }
2962
2963 key.offset = found_key.offset - 1;
2964 free_extent_buffer(log->node);
2965 kfree(log);
2966
2967 if (found_key.offset == 0)
2968 break;
2969 }
2970 btrfs_release_path(log_root_tree, path);
2971
2972 /* step one is to pin it all, step two is to replay just inodes */
2973 if (wc.pin) {
2974 wc.pin = 0;
2975 wc.process_func = replay_one_buffer;
2976 wc.stage = LOG_WALK_REPLAY_INODES;
2977 goto again;
2978 }
2979 /* step three is to replay everything */
2980 if (wc.stage < LOG_WALK_REPLAY_ALL) {
2981 wc.stage++;
2982 goto again;
2983 }
2984
2985 btrfs_free_path(path);
2986
2987 free_extent_buffer(log_root_tree->node);
2988 log_root_tree->log_root = NULL;
2989 fs_info->log_root_recovering = 0;
2990
2991 /* step 4: commit the transaction, which also unpins the blocks */
2992 btrfs_commit_transaction(trans, fs_info->tree_root);
2993
2994 kfree(log_root_tree);
2995 return 0;
2996}
generated by cgit v1.2.2 (git 2.25.0) at 2025-01-31 19:07:19 -0500