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Linux 3.2.58
[linux/fpc-iii.git] / fs / btrfs / disk-io.c
blobcfdf6feec104c9a5919d054ba36029c86d9125fb
1 /*
2 * Copyright (C) 2007 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/fs.h>
20 #include <linux/blkdev.h>
21 #include <linux/scatterlist.h>
22 #include <linux/swap.h>
23 #include <linux/radix-tree.h>
24 #include <linux/writeback.h>
25 #include <linux/buffer_head.h>
26 #include <linux/workqueue.h>
27 #include <linux/kthread.h>
28 #include <linux/freezer.h>
29 #include <linux/crc32c.h>
30 #include <linux/slab.h>
31 #include <linux/migrate.h>
32 #include <linux/ratelimit.h>
33 #include <asm/unaligned.h>
34 #include "compat.h"
35 #include "ctree.h"
36 #include "disk-io.h"
37 #include "transaction.h"
38 #include "btrfs_inode.h"
39 #include "volumes.h"
40 #include "print-tree.h"
41 #include "async-thread.h"
42 #include "locking.h"
43 #include "tree-log.h"
44 #include "free-space-cache.h"
45 #include "inode-map.h"
46
47 static struct extent_io_ops btree_extent_io_ops;
48 static void end_workqueue_fn(struct btrfs_work *work);
49 static void free_fs_root(struct btrfs_root *root);
50 static void btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
51 int read_only);
52 static int btrfs_destroy_ordered_operations(struct btrfs_root *root);
53 static int btrfs_destroy_ordered_extents(struct btrfs_root *root);
54 static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
55 struct btrfs_root *root);
56 static int btrfs_destroy_pending_snapshots(struct btrfs_transaction *t);
57 static int btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
58 static int btrfs_destroy_marked_extents(struct btrfs_root *root,
59 struct extent_io_tree *dirty_pages,
60 int mark);
61 static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
62 struct extent_io_tree *pinned_extents);
63 static int btrfs_cleanup_transaction(struct btrfs_root *root);
64
65 /*
66 * end_io_wq structs are used to do processing in task context when an IO is
67 * complete. This is used during reads to verify checksums, and it is used
68 * by writes to insert metadata for new file extents after IO is complete.
69 */
70 struct end_io_wq {
71 struct bio *bio;
72 bio_end_io_t *end_io;
73 void *private;
74 struct btrfs_fs_info *info;
75 int error;
76 int metadata;
77 struct list_head list;
78 struct btrfs_work work;
79 };
80
81 /*
82 * async submit bios are used to offload expensive checksumming
83 * onto the worker threads. They checksum file and metadata bios
84 * just before they are sent down the IO stack.
85 */
86 struct async_submit_bio {
87 struct inode *inode;
88 struct bio *bio;
89 struct list_head list;
90 extent_submit_bio_hook_t *submit_bio_start;
91 extent_submit_bio_hook_t *submit_bio_done;
92 int rw;
93 int mirror_num;
94 unsigned long bio_flags;
95 /*
96 * bio_offset is optional, can be used if the pages in the bio
97 * can't tell us where in the file the bio should go
98 */
99 u64 bio_offset;
100 struct btrfs_work work;
101 };
102
103 /*
104 * Lockdep class keys for extent_buffer->lock's in this root. For a given
105 * eb, the lockdep key is determined by the btrfs_root it belongs to and
106 * the level the eb occupies in the tree.
107 *
108 * Different roots are used for different purposes and may nest inside each
109 * other and they require separate keysets. As lockdep keys should be
110 * static, assign keysets according to the purpose of the root as indicated
111 * by btrfs_root->objectid. This ensures that all special purpose roots
112 * have separate keysets.
113 *
114 * Lock-nesting across peer nodes is always done with the immediate parent
115 * node locked thus preventing deadlock. As lockdep doesn't know this, use
116 * subclass to avoid triggering lockdep warning in such cases.
117 *
118 * The key is set by the readpage_end_io_hook after the buffer has passed
119 * csum validation but before the pages are unlocked. It is also set by
120 * btrfs_init_new_buffer on freshly allocated blocks.
121 *
122 * We also add a check to make sure the highest level of the tree is the
123 * same as our lockdep setup here. If BTRFS_MAX_LEVEL changes, this code
124 * needs update as well.
125 */
126 #ifdef CONFIG_DEBUG_LOCK_ALLOC
127 # if BTRFS_MAX_LEVEL != 8
128 # error
129 # endif
130
131 static struct btrfs_lockdep_keyset {
132 u64 id; /* root objectid */
133 const char *name_stem; /* lock name stem */
134 char names[BTRFS_MAX_LEVEL + 1][20];
135 struct lock_class_key keys[BTRFS_MAX_LEVEL + 1];
136 } btrfs_lockdep_keysets[] = {
137 { .id = BTRFS_ROOT_TREE_OBJECTID, .name_stem = "root" },
138 { .id = BTRFS_EXTENT_TREE_OBJECTID, .name_stem = "extent" },
139 { .id = BTRFS_CHUNK_TREE_OBJECTID, .name_stem = "chunk" },
140 { .id = BTRFS_DEV_TREE_OBJECTID, .name_stem = "dev" },
141 { .id = BTRFS_FS_TREE_OBJECTID, .name_stem = "fs" },
142 { .id = BTRFS_CSUM_TREE_OBJECTID, .name_stem = "csum" },
143 { .id = BTRFS_ORPHAN_OBJECTID, .name_stem = "orphan" },
144 { .id = BTRFS_TREE_LOG_OBJECTID, .name_stem = "log" },
145 { .id = BTRFS_TREE_RELOC_OBJECTID, .name_stem = "treloc" },
146 { .id = BTRFS_DATA_RELOC_TREE_OBJECTID, .name_stem = "dreloc" },
147 { .id = 0, .name_stem = "tree" },
148 };
149
150 void __init btrfs_init_lockdep(void)
151 {
152 int i, j;
153
154 /* initialize lockdep class names */
155 for (i = 0; i < ARRAY_SIZE(btrfs_lockdep_keysets); i++) {
156 struct btrfs_lockdep_keyset *ks = &btrfs_lockdep_keysets[i];
157
158 for (j = 0; j < ARRAY_SIZE(ks->names); j++)
159 snprintf(ks->names[j], sizeof(ks->names[j]),
160 "btrfs-%s-%02d", ks->name_stem, j);
161 }
162 }
163
164 void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb,
165 int level)
166 {
167 struct btrfs_lockdep_keyset *ks;
168
169 BUG_ON(level >= ARRAY_SIZE(ks->keys));
170
171 /* find the matching keyset, id 0 is the default entry */
172 for (ks = btrfs_lockdep_keysets; ks->id; ks++)
173 if (ks->id == objectid)
174 break;
175
176 lockdep_set_class_and_name(&eb->lock,
177 &ks->keys[level], ks->names[level]);
178 }
179
180 #endif
181
182 /*
183 * extents on the btree inode are pretty simple, there's one extent
184 * that covers the entire device
185 */
186 static struct extent_map *btree_get_extent(struct inode *inode,
187 struct page *page, size_t pg_offset, u64 start, u64 len,
188 int create)
189 {
190 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
191 struct extent_map *em;
192 int ret;
193
194 read_lock(&em_tree->lock);
195 em = lookup_extent_mapping(em_tree, start, len);
196 if (em) {
197 em->bdev =
198 BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
199 read_unlock(&em_tree->lock);
200 goto out;
201 }
202 read_unlock(&em_tree->lock);
203
204 em = alloc_extent_map();
205 if (!em) {
206 em = ERR_PTR(-ENOMEM);
207 goto out;
208 }
209 em->start = 0;
210 em->len = (u64)-1;
211 em->block_len = (u64)-1;
212 em->block_start = 0;
213 em->bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
214
215 write_lock(&em_tree->lock);
216 ret = add_extent_mapping(em_tree, em);
217 if (ret == -EEXIST) {
218 u64 failed_start = em->start;
219 u64 failed_len = em->len;
220
221 free_extent_map(em);
222 em = lookup_extent_mapping(em_tree, start, len);
223 if (em) {
224 ret = 0;
225 } else {
226 em = lookup_extent_mapping(em_tree, failed_start,
227 failed_len);
228 ret = -EIO;
229 }
230 } else if (ret) {
231 free_extent_map(em);
232 em = NULL;
233 }
234 write_unlock(&em_tree->lock);
235
236 if (ret)
237 em = ERR_PTR(ret);
238 out:
239 return em;
240 }
241
242 u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len)
243 {
244 return crc32c(seed, data, len);
245 }
246
247 void btrfs_csum_final(u32 crc, char *result)
248 {
249 put_unaligned_le32(~crc, result);
250 }
251
252 /*
253 * compute the csum for a btree block, and either verify it or write it
254 * into the csum field of the block.
255 */
256 static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
257 int verify)
258 {
259 u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
260 char *result = NULL;
261 unsigned long len;
262 unsigned long cur_len;
263 unsigned long offset = BTRFS_CSUM_SIZE;
264 char *kaddr;
265 unsigned long map_start;
266 unsigned long map_len;
267 int err;
268 u32 crc = ~(u32)0;
269 unsigned long inline_result;
270
271 len = buf->len - offset;
272 while (len > 0) {
273 err = map_private_extent_buffer(buf, offset, 32,
274 &kaddr, &map_start, &map_len);
275 if (err)
276 return 1;
277 cur_len = min(len, map_len - (offset - map_start));
278 crc = btrfs_csum_data(root, kaddr + offset - map_start,
279 crc, cur_len);
280 len -= cur_len;
281 offset += cur_len;
282 }
283 if (csum_size > sizeof(inline_result)) {
284 result = kzalloc(csum_size * sizeof(char), GFP_NOFS);
285 if (!result)
286 return 1;
287 } else {
288 result = (char *)&inline_result;
289 }
290
291 btrfs_csum_final(crc, result);
292
293 if (verify) {
294 if (memcmp_extent_buffer(buf, result, 0, csum_size)) {
295 u32 val;
296 u32 found = 0;
297 memcpy(&found, result, csum_size);
298
299 read_extent_buffer(buf, &val, 0, csum_size);
300 printk_ratelimited(KERN_INFO "btrfs: %s checksum verify "
301 "failed on %llu wanted %X found %X "
302 "level %d\n",
303 root->fs_info->sb->s_id,
304 (unsigned long long)buf->start, val, found,
305 btrfs_header_level(buf));
306 if (result != (char *)&inline_result)
307 kfree(result);
308 return 1;
309 }
310 } else {
311 write_extent_buffer(buf, result, 0, csum_size);
312 }
313 if (result != (char *)&inline_result)
314 kfree(result);
315 return 0;
316 }
317
318 /*
319 * we can't consider a given block up to date unless the transid of the
320 * block matches the transid in the parent node's pointer. This is how we
321 * detect blocks that either didn't get written at all or got written
322 * in the wrong place.
323 */
324 static int verify_parent_transid(struct extent_io_tree *io_tree,
325 struct extent_buffer *eb, u64 parent_transid)
326 {
327 struct extent_state *cached_state = NULL;
328 int ret;
329
330 if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
331 return 0;
332
333 lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1,
334 0, &cached_state, GFP_NOFS);
335 if (extent_buffer_uptodate(io_tree, eb, cached_state) &&
336 btrfs_header_generation(eb) == parent_transid) {
337 ret = 0;
338 goto out;
339 }
340 printk_ratelimited("parent transid verify failed on %llu wanted %llu "
341 "found %llu\n",
342 (unsigned long long)eb->start,
343 (unsigned long long)parent_transid,
344 (unsigned long long)btrfs_header_generation(eb));
345 ret = 1;
346 clear_extent_buffer_uptodate(io_tree, eb, &cached_state);
347 out:
348 unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
349 &cached_state, GFP_NOFS);
350 return ret;
351 }
352
353 /*
354 * helper to read a given tree block, doing retries as required when
355 * the checksums don't match and we have alternate mirrors to try.
356 */
357 static int btree_read_extent_buffer_pages(struct btrfs_root *root,
358 struct extent_buffer *eb,
359 u64 start, u64 parent_transid)
360 {
361 struct extent_io_tree *io_tree;
362 int ret;
363 int num_copies = 0;
364 int mirror_num = 0;
365
366 clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
367 io_tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree;
368 while (1) {
369 ret = read_extent_buffer_pages(io_tree, eb, start,
370 WAIT_COMPLETE,
371 btree_get_extent, mirror_num);
372 if (!ret &&
373 !verify_parent_transid(io_tree, eb, parent_transid))
374 return ret;
375
376 /*
377 * This buffer's crc is fine, but its contents are corrupted, so
378 * there is no reason to read the other copies, they won't be
379 * any less wrong.
380 */
381 if (test_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags))
382 return ret;
383
384 num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
385 eb->start, eb->len);
386 if (num_copies == 1)
387 return ret;
388
389 mirror_num++;
390 if (mirror_num > num_copies)
391 return ret;
392 }
393 return -EIO;
394 }
395
396 /*
397 * checksum a dirty tree block before IO. This has extra checks to make sure
398 * we only fill in the checksum field in the first page of a multi-page block
399 */
400
401 static int csum_dirty_buffer(struct btrfs_root *root, struct page *page)
402 {
403 struct extent_io_tree *tree;
404 u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
405 u64 found_start;
406 unsigned long len;
407 struct extent_buffer *eb;
408 int ret;
409
410 tree = &BTRFS_I(page->mapping->host)->io_tree;
411
412 if (page->private == EXTENT_PAGE_PRIVATE) {
413 WARN_ON(1);
414 goto out;
415 }
416 if (!page->private) {
417 WARN_ON(1);
418 goto out;
419 }
420 len = page->private >> 2;
421 WARN_ON(len == 0);
422
423 eb = alloc_extent_buffer(tree, start, len, page);
424 if (eb == NULL) {
425 WARN_ON(1);
426 goto out;
427 }
428 ret = btree_read_extent_buffer_pages(root, eb, start + PAGE_CACHE_SIZE,
429 btrfs_header_generation(eb));
430 BUG_ON(ret);
431 WARN_ON(!btrfs_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN));
432
433 found_start = btrfs_header_bytenr(eb);
434 if (found_start != start) {
435 WARN_ON(1);
436 goto err;
437 }
438 if (eb->first_page != page) {
439 WARN_ON(1);
440 goto err;
441 }
442 if (!PageUptodate(page)) {
443 WARN_ON(1);
444 goto err;
445 }
446 csum_tree_block(root, eb, 0);
447 err:
448 free_extent_buffer(eb);
449 out:
450 return 0;
451 }
452
453 static int check_tree_block_fsid(struct btrfs_root *root,
454 struct extent_buffer *eb)
455 {
456 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
457 u8 fsid[BTRFS_UUID_SIZE];
458 int ret = 1;
459
460 read_extent_buffer(eb, fsid, (unsigned long)btrfs_header_fsid(eb),
461 BTRFS_FSID_SIZE);
462 while (fs_devices) {
463 if (!memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE)) {
464 ret = 0;
465 break;
466 }
467 fs_devices = fs_devices->seed;
468 }
469 return ret;
470 }
471
472 #define CORRUPT(reason, eb, root, slot) \
473 printk(KERN_CRIT "btrfs: corrupt leaf, %s: block=%llu," \
474 "root=%llu, slot=%d\n", reason, \
475 (unsigned long long)btrfs_header_bytenr(eb), \
476 (unsigned long long)root->objectid, slot)
477
478 static noinline int check_leaf(struct btrfs_root *root,
479 struct extent_buffer *leaf)
480 {
481 struct btrfs_key key;
482 struct btrfs_key leaf_key;
483 u32 nritems = btrfs_header_nritems(leaf);
484 int slot;
485
486 if (nritems == 0)
487 return 0;
488
489 /* Check the 0 item */
490 if (btrfs_item_offset_nr(leaf, 0) + btrfs_item_size_nr(leaf, 0) !=
491 BTRFS_LEAF_DATA_SIZE(root)) {
492 CORRUPT("invalid item offset size pair", leaf, root, 0);
493 return -EIO;
494 }
495
496 /*
497 * Check to make sure each items keys are in the correct order and their
498 * offsets make sense. We only have to loop through nritems-1 because
499 * we check the current slot against the next slot, which verifies the
500 * next slot's offset+size makes sense and that the current's slot
501 * offset is correct.
502 */
503 for (slot = 0; slot < nritems - 1; slot++) {
504 btrfs_item_key_to_cpu(leaf, &leaf_key, slot);
505 btrfs_item_key_to_cpu(leaf, &key, slot + 1);
506
507 /* Make sure the keys are in the right order */
508 if (btrfs_comp_cpu_keys(&leaf_key, &key) >= 0) {
509 CORRUPT("bad key order", leaf, root, slot);
510 return -EIO;
511 }
512
513 /*
514 * Make sure the offset and ends are right, remember that the
515 * item data starts at the end of the leaf and grows towards the
516 * front.
517 */
518 if (btrfs_item_offset_nr(leaf, slot) !=
519 btrfs_item_end_nr(leaf, slot + 1)) {
520 CORRUPT("slot offset bad", leaf, root, slot);
521 return -EIO;
522 }
523
524 /*
525 * Check to make sure that we don't point outside of the leaf,
526 * just incase all the items are consistent to eachother, but
527 * all point outside of the leaf.
528 */
529 if (btrfs_item_end_nr(leaf, slot) >
530 BTRFS_LEAF_DATA_SIZE(root)) {
531 CORRUPT("slot end outside of leaf", leaf, root, slot);
532 return -EIO;
533 }
534 }
535
536 return 0;
537 }
538
539 static int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
540 struct extent_state *state)
541 {
542 struct extent_io_tree *tree;
543 u64 found_start;
544 int found_level;
545 unsigned long len;
546 struct extent_buffer *eb;
547 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
548 int ret = 0;
549
550 tree = &BTRFS_I(page->mapping->host)->io_tree;
551 if (page->private == EXTENT_PAGE_PRIVATE)
552 goto out;
553 if (!page->private)
554 goto out;
555
556 len = page->private >> 2;
557 WARN_ON(len == 0);
558
559 eb = alloc_extent_buffer(tree, start, len, page);
560 if (eb == NULL) {
561 ret = -EIO;
562 goto out;
563 }
564
565 found_start = btrfs_header_bytenr(eb);
566 if (found_start != start) {
567 printk_ratelimited(KERN_INFO "btrfs bad tree block start "
568 "%llu %llu\n",
569 (unsigned long long)found_start,
570 (unsigned long long)eb->start);
571 ret = -EIO;
572 goto err;
573 }
574 if (eb->first_page != page) {
575 printk(KERN_INFO "btrfs bad first page %lu %lu\n",
576 eb->first_page->index, page->index);
577 WARN_ON(1);
578 ret = -EIO;
579 goto err;
580 }
581 if (check_tree_block_fsid(root, eb)) {
582 printk_ratelimited(KERN_INFO "btrfs bad fsid on block %llu\n",
583 (unsigned long long)eb->start);
584 ret = -EIO;
585 goto err;
586 }
587 found_level = btrfs_header_level(eb);
588
589 btrfs_set_buffer_lockdep_class(btrfs_header_owner(eb),
590 eb, found_level);
591
592 ret = csum_tree_block(root, eb, 1);
593 if (ret) {
594 ret = -EIO;
595 goto err;
596 }
597
598 /*
599 * If this is a leaf block and it is corrupt, set the corrupt bit so
600 * that we don't try and read the other copies of this block, just
601 * return -EIO.
602 */
603 if (found_level == 0 && check_leaf(root, eb)) {
604 set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
605 ret = -EIO;
606 }
607
608 end = min_t(u64, eb->len, PAGE_CACHE_SIZE);
609 end = eb->start + end - 1;
610 err:
611 if (test_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags)) {
612 clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags);
613 btree_readahead_hook(root, eb, eb->start, ret);
614 }
615
616 free_extent_buffer(eb);
617 out:
618 return ret;
619 }
620
621 static int btree_io_failed_hook(struct bio *failed_bio,
622 struct page *page, u64 start, u64 end,
623 int mirror_num, struct extent_state *state)
624 {
625 struct extent_io_tree *tree;
626 unsigned long len;
627 struct extent_buffer *eb;
628 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
629
630 tree = &BTRFS_I(page->mapping->host)->io_tree;
631 if (page->private == EXTENT_PAGE_PRIVATE)
632 goto out;
633 if (!page->private)
634 goto out;
635
636 len = page->private >> 2;
637 WARN_ON(len == 0);
638
639 eb = alloc_extent_buffer(tree, start, len, page);
640 if (eb == NULL)
641 goto out;
642
643 if (test_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags)) {
644 clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags);
645 btree_readahead_hook(root, eb, eb->start, -EIO);
646 }
647 free_extent_buffer(eb);
648
649 out:
650 return -EIO; /* we fixed nothing */
651 }
652
653 static void end_workqueue_bio(struct bio *bio, int err)
654 {
655 struct end_io_wq *end_io_wq = bio->bi_private;
656 struct btrfs_fs_info *fs_info;
657
658 fs_info = end_io_wq->info;
659 end_io_wq->error = err;
660 end_io_wq->work.func = end_workqueue_fn;
661 end_io_wq->work.flags = 0;
662
663 if (bio->bi_rw & REQ_WRITE) {
664 if (end_io_wq->metadata == 1)
665 btrfs_queue_worker(&fs_info->endio_meta_write_workers,
666 &end_io_wq->work);
667 else if (end_io_wq->metadata == 2)
668 btrfs_queue_worker(&fs_info->endio_freespace_worker,
669 &end_io_wq->work);
670 else
671 btrfs_queue_worker(&fs_info->endio_write_workers,
672 &end_io_wq->work);
673 } else {
674 if (end_io_wq->metadata)
675 btrfs_queue_worker(&fs_info->endio_meta_workers,
676 &end_io_wq->work);
677 else
678 btrfs_queue_worker(&fs_info->endio_workers,
679 &end_io_wq->work);
680 }
681 }
682
683 /*
684 * For the metadata arg you want
685 *
686 * 0 - if data
687 * 1 - if normal metadta
688 * 2 - if writing to the free space cache area
689 */
690 int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
691 int metadata)
692 {
693 struct end_io_wq *end_io_wq;
694 end_io_wq = kmalloc(sizeof(*end_io_wq), GFP_NOFS);
695 if (!end_io_wq)
696 return -ENOMEM;
697
698 end_io_wq->private = bio->bi_private;
699 end_io_wq->end_io = bio->bi_end_io;
700 end_io_wq->info = info;
701 end_io_wq->error = 0;
702 end_io_wq->bio = bio;
703 end_io_wq->metadata = metadata;
704
705 bio->bi_private = end_io_wq;
706 bio->bi_end_io = end_workqueue_bio;
707 return 0;
708 }
709
710 unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info)
711 {
712 unsigned long limit = min_t(unsigned long,
713 info->workers.max_workers,
714 info->fs_devices->open_devices);
715 return 256 * limit;
716 }
717
718 static void run_one_async_start(struct btrfs_work *work)
719 {
720 struct async_submit_bio *async;
721
722 async = container_of(work, struct async_submit_bio, work);
723 async->submit_bio_start(async->inode, async->rw, async->bio,
724 async->mirror_num, async->bio_flags,
725 async->bio_offset);
726 }
727
728 static void run_one_async_done(struct btrfs_work *work)
729 {
730 struct btrfs_fs_info *fs_info;
731 struct async_submit_bio *async;
732 int limit;
733
734 async = container_of(work, struct async_submit_bio, work);
735 fs_info = BTRFS_I(async->inode)->root->fs_info;
736
737 limit = btrfs_async_submit_limit(fs_info);
738 limit = limit * 2 / 3;
739
740 atomic_dec(&fs_info->nr_async_submits);
741
742 if (atomic_read(&fs_info->nr_async_submits) < limit &&
743 waitqueue_active(&fs_info->async_submit_wait))
744 wake_up(&fs_info->async_submit_wait);
745
746 async->submit_bio_done(async->inode, async->rw, async->bio,
747 async->mirror_num, async->bio_flags,
748 async->bio_offset);
749 }
750
751 static void run_one_async_free(struct btrfs_work *work)
752 {
753 struct async_submit_bio *async;
754
755 async = container_of(work, struct async_submit_bio, work);
756 kfree(async);
757 }
758
759 int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode,
760 int rw, struct bio *bio, int mirror_num,
761 unsigned long bio_flags,
762 u64 bio_offset,
763 extent_submit_bio_hook_t *submit_bio_start,
764 extent_submit_bio_hook_t *submit_bio_done)
765 {
766 struct async_submit_bio *async;
767
768 async = kmalloc(sizeof(*async), GFP_NOFS);
769 if (!async)
770 return -ENOMEM;
771
772 async->inode = inode;
773 async->rw = rw;
774 async->bio = bio;
775 async->mirror_num = mirror_num;
776 async->submit_bio_start = submit_bio_start;
777 async->submit_bio_done = submit_bio_done;
778
779 async->work.func = run_one_async_start;
780 async->work.ordered_func = run_one_async_done;
781 async->work.ordered_free = run_one_async_free;
782
783 async->work.flags = 0;
784 async->bio_flags = bio_flags;
785 async->bio_offset = bio_offset;
786
787 atomic_inc(&fs_info->nr_async_submits);
788
789 if (rw & REQ_SYNC)
790 btrfs_set_work_high_prio(&async->work);
791
792 btrfs_queue_worker(&fs_info->workers, &async->work);
793
794 while (atomic_read(&fs_info->async_submit_draining) &&
795 atomic_read(&fs_info->nr_async_submits)) {
796 wait_event(fs_info->async_submit_wait,
797 (atomic_read(&fs_info->nr_async_submits) == 0));
798 }
799
800 return 0;
801 }
802
803 static int btree_csum_one_bio(struct bio *bio)
804 {
805 struct bio_vec *bvec = bio->bi_io_vec;
806 int bio_index = 0;
807 struct btrfs_root *root;
808
809 WARN_ON(bio->bi_vcnt <= 0);
810 while (bio_index < bio->bi_vcnt) {
811 root = BTRFS_I(bvec->bv_page->mapping->host)->root;
812 csum_dirty_buffer(root, bvec->bv_page);
813 bio_index++;
814 bvec++;
815 }
816 return 0;
817 }
818
819 static int __btree_submit_bio_start(struct inode *inode, int rw,
820 struct bio *bio, int mirror_num,
821 unsigned long bio_flags,
822 u64 bio_offset)
823 {
824 /*
825 * when we're called for a write, we're already in the async
826 * submission context. Just jump into btrfs_map_bio
827 */
828 btree_csum_one_bio(bio);
829 return 0;
830 }
831
832 static int __btree_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
833 int mirror_num, unsigned long bio_flags,
834 u64 bio_offset)
835 {
836 /*
837 * when we're called for a write, we're already in the async
838 * submission context. Just jump into btrfs_map_bio
839 */
840 return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio, mirror_num, 1);
841 }
842
843 static int btree_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
844 int mirror_num, unsigned long bio_flags,
845 u64 bio_offset)
846 {
847 int ret;
848
849 ret = btrfs_bio_wq_end_io(BTRFS_I(inode)->root->fs_info,
850 bio, 1);
851 BUG_ON(ret);
852
853 if (!(rw & REQ_WRITE)) {
854 /*
855 * called for a read, do the setup so that checksum validation
856 * can happen in the async kernel threads
857 */
858 return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio,
859 mirror_num, 0);
860 }
861
862 /*
863 * kthread helpers are used to submit writes so that checksumming
864 * can happen in parallel across all CPUs
865 */
866 return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
867 inode, rw, bio, mirror_num, 0,
868 bio_offset,
869 __btree_submit_bio_start,
870 __btree_submit_bio_done);
871 }
872
873 #ifdef CONFIG_MIGRATION
874 static int btree_migratepage(struct address_space *mapping,
875 struct page *newpage, struct page *page,
876 enum migrate_mode mode)
877 {
878 /*
879 * we can't safely write a btree page from here,
880 * we haven't done the locking hook
881 */
882 if (PageDirty(page))
883 return -EAGAIN;
884 /*
885 * Buffers may be managed in a filesystem specific way.
886 * We must have no buffers or drop them.
887 */
888 if (page_has_private(page) &&
889 !try_to_release_page(page, GFP_KERNEL))
890 return -EAGAIN;
891 return migrate_page(mapping, newpage, page, mode);
892 }
893 #endif
894
895 static int btree_writepage(struct page *page, struct writeback_control *wbc)
896 {
897 struct extent_io_tree *tree;
898 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
899 struct extent_buffer *eb;
900 int was_dirty;
901
902 tree = &BTRFS_I(page->mapping->host)->io_tree;
903 if (!(current->flags & PF_MEMALLOC)) {
904 return extent_write_full_page(tree, page,
905 btree_get_extent, wbc);
906 }
907
908 redirty_page_for_writepage(wbc, page);
909 eb = btrfs_find_tree_block(root, page_offset(page), PAGE_CACHE_SIZE);
910 WARN_ON(!eb);
911
912 was_dirty = test_and_set_bit(EXTENT_BUFFER_DIRTY, &eb->bflags);
913 if (!was_dirty) {
914 spin_lock(&root->fs_info->delalloc_lock);
915 root->fs_info->dirty_metadata_bytes += PAGE_CACHE_SIZE;
916 spin_unlock(&root->fs_info->delalloc_lock);
917 }
918 free_extent_buffer(eb);
919
920 unlock_page(page);
921 return 0;
922 }
923
924 static int btree_writepages(struct address_space *mapping,
925 struct writeback_control *wbc)
926 {
927 struct extent_io_tree *tree;
928 tree = &BTRFS_I(mapping->host)->io_tree;
929 if (wbc->sync_mode == WB_SYNC_NONE) {
930 struct btrfs_root *root = BTRFS_I(mapping->host)->root;
931 u64 num_dirty;
932 unsigned long thresh = 32 * 1024 * 1024;
933
934 if (wbc->for_kupdate)
935 return 0;
936
937 /* this is a bit racy, but that's ok */
938 num_dirty = root->fs_info->dirty_metadata_bytes;
939 if (num_dirty < thresh)
940 return 0;
941 }
942 return extent_writepages(tree, mapping, btree_get_extent, wbc);
943 }
944
945 static int btree_readpage(struct file *file, struct page *page)
946 {
947 struct extent_io_tree *tree;
948 tree = &BTRFS_I(page->mapping->host)->io_tree;
949 return extent_read_full_page(tree, page, btree_get_extent, 0);
950 }
951
952 static int btree_releasepage(struct page *page, gfp_t gfp_flags)
953 {
954 struct extent_io_tree *tree;
955 struct extent_map_tree *map;
956 int ret;
957
958 if (PageWriteback(page) || PageDirty(page))
959 return 0;
960
961 tree = &BTRFS_I(page->mapping->host)->io_tree;
962 map = &BTRFS_I(page->mapping->host)->extent_tree;
963
964 ret = try_release_extent_state(map, tree, page, gfp_flags);
965 if (!ret)
966 return 0;
967
968 ret = try_release_extent_buffer(tree, page);
969 if (ret == 1) {
970 ClearPagePrivate(page);
971 set_page_private(page, 0);
972 page_cache_release(page);
973 }
974
975 return ret;
976 }
977
978 static void btree_invalidatepage(struct page *page, unsigned long offset)
979 {
980 struct extent_io_tree *tree;
981 tree = &BTRFS_I(page->mapping->host)->io_tree;
982 extent_invalidatepage(tree, page, offset);
983 btree_releasepage(page, GFP_NOFS);
984 if (PagePrivate(page)) {
985 printk(KERN_WARNING "btrfs warning page private not zero "
986 "on page %llu\n", (unsigned long long)page_offset(page));
987 ClearPagePrivate(page);
988 set_page_private(page, 0);
989 page_cache_release(page);
990 }
991 }
992
993 static const struct address_space_operations btree_aops = {
994 .readpage = btree_readpage,
995 .writepage = btree_writepage,
996 .writepages = btree_writepages,
997 .releasepage = btree_releasepage,
998 .invalidatepage = btree_invalidatepage,
999 #ifdef CONFIG_MIGRATION
1000 .migratepage = btree_migratepage,
1001 #endif
1002 };
1003
1004 int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
1005 u64 parent_transid)
1006 {
1007 struct extent_buffer *buf = NULL;
1008 struct inode *btree_inode = root->fs_info->btree_inode;
1009 int ret = 0;
1010
1011 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
1012 if (!buf)
1013 return 0;
1014 read_extent_buffer_pages(&BTRFS_I(btree_inode)->io_tree,
1015 buf, 0, WAIT_NONE, btree_get_extent, 0);
1016 free_extent_buffer(buf);
1017 return ret;
1018 }
1019
1020 int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr, u32 blocksize,
1021 int mirror_num, struct extent_buffer **eb)
1022 {
1023 struct extent_buffer *buf = NULL;
1024 struct inode *btree_inode = root->fs_info->btree_inode;
1025 struct extent_io_tree *io_tree = &BTRFS_I(btree_inode)->io_tree;
1026 int ret;
1027
1028 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
1029 if (!buf)
1030 return 0;
1031
1032 set_bit(EXTENT_BUFFER_READAHEAD, &buf->bflags);
1033
1034 ret = read_extent_buffer_pages(io_tree, buf, 0, WAIT_PAGE_LOCK,
1035 btree_get_extent, mirror_num);
1036 if (ret) {
1037 free_extent_buffer(buf);
1038 return ret;
1039 }
1040
1041 if (test_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags)) {
1042 free_extent_buffer(buf);
1043 return -EIO;
1044 } else if (extent_buffer_uptodate(io_tree, buf, NULL)) {
1045 *eb = buf;
1046 } else {
1047 free_extent_buffer(buf);
1048 }
1049 return 0;
1050 }
1051
1052 struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
1053 u64 bytenr, u32 blocksize)
1054 {
1055 struct inode *btree_inode = root->fs_info->btree_inode;
1056 struct extent_buffer *eb;
1057 eb = find_extent_buffer(&BTRFS_I(btree_inode)->io_tree,
1058 bytenr, blocksize);
1059 return eb;
1060 }
1061
1062 struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
1063 u64 bytenr, u32 blocksize)
1064 {
1065 struct inode *btree_inode = root->fs_info->btree_inode;
1066 struct extent_buffer *eb;
1067
1068 eb = alloc_extent_buffer(&BTRFS_I(btree_inode)->io_tree,
1069 bytenr, blocksize, NULL);
1070 return eb;
1071 }
1072
1073
1074 int btrfs_write_tree_block(struct extent_buffer *buf)
1075 {
1076 return filemap_fdatawrite_range(buf->first_page->mapping, buf->start,
1077 buf->start + buf->len - 1);
1078 }
1079
1080 int btrfs_wait_tree_block_writeback(struct extent_buffer *buf)
1081 {
1082 return filemap_fdatawait_range(buf->first_page->mapping,
1083 buf->start, buf->start + buf->len - 1);
1084 }
1085
1086 struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
1087 u32 blocksize, u64 parent_transid)
1088 {
1089 struct extent_buffer *buf = NULL;
1090 int ret;
1091
1092 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
1093 if (!buf)
1094 return NULL;
1095
1096 ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
1097
1098 if (ret == 0)
1099 set_bit(EXTENT_BUFFER_UPTODATE, &buf->bflags);
1100 return buf;
1101
1102 }
1103
1104 int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
1105 struct extent_buffer *buf)
1106 {
1107 struct inode *btree_inode = root->fs_info->btree_inode;
1108 if (btrfs_header_generation(buf) ==
1109 root->fs_info->running_transaction->transid) {
1110 btrfs_assert_tree_locked(buf);
1111
1112 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) {
1113 spin_lock(&root->fs_info->delalloc_lock);
1114 if (root->fs_info->dirty_metadata_bytes >= buf->len)
1115 root->fs_info->dirty_metadata_bytes -= buf->len;
1116 else
1117 WARN_ON(1);
1118 spin_unlock(&root->fs_info->delalloc_lock);
1119 }
1120
1121 /* ugh, clear_extent_buffer_dirty needs to lock the page */
1122 btrfs_set_lock_blocking(buf);
1123 clear_extent_buffer_dirty(&BTRFS_I(btree_inode)->io_tree,
1124 buf);
1125 }
1126 return 0;
1127 }
1128
1129 static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
1130 u32 stripesize, struct btrfs_root *root,
1131 struct btrfs_fs_info *fs_info,
1132 u64 objectid)
1133 {
1134 root->node = NULL;
1135 root->commit_root = NULL;
1136 root->sectorsize = sectorsize;
1137 root->nodesize = nodesize;
1138 root->leafsize = leafsize;
1139 root->stripesize = stripesize;
1140 root->ref_cows = 0;
1141 root->track_dirty = 0;
1142 root->in_radix = 0;
1143 root->orphan_item_inserted = 0;
1144 root->orphan_cleanup_state = 0;
1145
1146 root->fs_info = fs_info;
1147 root->objectid = objectid;
1148 root->last_trans = 0;
1149 root->highest_objectid = 0;
1150 root->name = NULL;
1151 root->inode_tree = RB_ROOT;
1152 INIT_RADIX_TREE(&root->delayed_nodes_tree, GFP_ATOMIC);
1153 root->block_rsv = NULL;
1154 root->orphan_block_rsv = NULL;
1155
1156 INIT_LIST_HEAD(&root->dirty_list);
1157 INIT_LIST_HEAD(&root->orphan_list);
1158 INIT_LIST_HEAD(&root->root_list);
1159 spin_lock_init(&root->orphan_lock);
1160 spin_lock_init(&root->inode_lock);
1161 spin_lock_init(&root->accounting_lock);
1162 mutex_init(&root->objectid_mutex);
1163 mutex_init(&root->log_mutex);
1164 init_waitqueue_head(&root->log_writer_wait);
1165 init_waitqueue_head(&root->log_commit_wait[0]);
1166 init_waitqueue_head(&root->log_commit_wait[1]);
1167 atomic_set(&root->log_commit[0], 0);
1168 atomic_set(&root->log_commit[1], 0);
1169 atomic_set(&root->log_writers, 0);
1170 root->log_batch = 0;
1171 root->log_transid = 0;
1172 root->last_log_commit = 0;
1173 extent_io_tree_init(&root->dirty_log_pages,
1174 fs_info->btree_inode->i_mapping);
1175
1176 memset(&root->root_key, 0, sizeof(root->root_key));
1177 memset(&root->root_item, 0, sizeof(root->root_item));
1178 memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
1179 memset(&root->root_kobj, 0, sizeof(root->root_kobj));
1180 root->defrag_trans_start = fs_info->generation;
1181 init_completion(&root->kobj_unregister);
1182 root->defrag_running = 0;
1183 root->root_key.objectid = objectid;
1184 root->anon_dev = 0;
1185 return 0;
1186 }
1187
1188 static int find_and_setup_root(struct btrfs_root *tree_root,
1189 struct btrfs_fs_info *fs_info,
1190 u64 objectid,
1191 struct btrfs_root *root)
1192 {
1193 int ret;
1194 u32 blocksize;
1195 u64 generation;
1196
1197 __setup_root(tree_root->nodesize, tree_root->leafsize,
1198 tree_root->sectorsize, tree_root->stripesize,
1199 root, fs_info, objectid);
1200 ret = btrfs_find_last_root(tree_root, objectid,
1201 &root->root_item, &root->root_key);
1202 if (ret > 0)
1203 return -ENOENT;
1204 BUG_ON(ret);
1205
1206 generation = btrfs_root_generation(&root->root_item);
1207 blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
1208 root->commit_root = NULL;
1209 root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
1210 blocksize, generation);
1211 if (!root->node || !btrfs_buffer_uptodate(root->node, generation)) {
1212 free_extent_buffer(root->node);
1213 root->node = NULL;
1214 return -EIO;
1215 }
1216 root->commit_root = btrfs_root_node(root);
1217 return 0;
1218 }
1219
1220 static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
1221 struct btrfs_fs_info *fs_info)
1222 {
1223 struct btrfs_root *root;
1224 struct btrfs_root *tree_root = fs_info->tree_root;
1225 struct extent_buffer *leaf;
1226
1227 root = kzalloc(sizeof(*root), GFP_NOFS);
1228 if (!root)
1229 return ERR_PTR(-ENOMEM);
1230
1231 __setup_root(tree_root->nodesize, tree_root->leafsize,
1232 tree_root->sectorsize, tree_root->stripesize,
1233 root, fs_info, BTRFS_TREE_LOG_OBJECTID);
1234
1235 root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
1236 root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1237 root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
1238 /*
1239 * log trees do not get reference counted because they go away
1240 * before a real commit is actually done. They do store pointers
1241 * to file data extents, and those reference counts still get
1242 * updated (along with back refs to the log tree).
1243 */
1244 root->ref_cows = 0;
1245
1246 leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 0,
1247 BTRFS_TREE_LOG_OBJECTID, NULL, 0, 0, 0);
1248 if (IS_ERR(leaf)) {
1249 kfree(root);
1250 return ERR_CAST(leaf);
1251 }
1252
1253 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
1254 btrfs_set_header_bytenr(leaf, leaf->start);
1255 btrfs_set_header_generation(leaf, trans->transid);
1256 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
1257 btrfs_set_header_owner(leaf, BTRFS_TREE_LOG_OBJECTID);
1258 root->node = leaf;
1259
1260 write_extent_buffer(root->node, root->fs_info->fsid,
1261 (unsigned long)btrfs_header_fsid(root->node),
1262 BTRFS_FSID_SIZE);
1263 btrfs_mark_buffer_dirty(root->node);
1264 btrfs_tree_unlock(root->node);
1265 return root;
1266 }
1267
1268 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
1269 struct btrfs_fs_info *fs_info)
1270 {
1271 struct btrfs_root *log_root;
1272
1273 log_root = alloc_log_tree(trans, fs_info);
1274 if (IS_ERR(log_root))
1275 return PTR_ERR(log_root);
1276 WARN_ON(fs_info->log_root_tree);
1277 fs_info->log_root_tree = log_root;
1278 return 0;
1279 }
1280
1281 int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
1282 struct btrfs_root *root)
1283 {
1284 struct btrfs_root *log_root;
1285 struct btrfs_inode_item *inode_item;
1286
1287 log_root = alloc_log_tree(trans, root->fs_info);
1288 if (IS_ERR(log_root))
1289 return PTR_ERR(log_root);
1290
1291 log_root->last_trans = trans->transid;
1292 log_root->root_key.offset = root->root_key.objectid;
1293
1294 inode_item = &log_root->root_item.inode;
1295 inode_item->generation = cpu_to_le64(1);
1296 inode_item->size = cpu_to_le64(3);
1297 inode_item->nlink = cpu_to_le32(1);
1298 inode_item->nbytes = cpu_to_le64(root->leafsize);
1299 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
1300
1301 btrfs_set_root_node(&log_root->root_item, log_root->node);
1302
1303 WARN_ON(root->log_root);
1304 root->log_root = log_root;
1305 root->log_transid = 0;
1306 root->last_log_commit = 0;
1307 return 0;
1308 }
1309
1310 struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
1311 struct btrfs_key *location)
1312 {
1313 struct btrfs_root *root;
1314 struct btrfs_fs_info *fs_info = tree_root->fs_info;
1315 struct btrfs_path *path;
1316 struct extent_buffer *l;
1317 u64 generation;
1318 u32 blocksize;
1319 int ret = 0;
1320
1321 root = kzalloc(sizeof(*root), GFP_NOFS);
1322 if (!root)
1323 return ERR_PTR(-ENOMEM);
1324 if (location->offset == (u64)-1) {
1325 ret = find_and_setup_root(tree_root, fs_info,
1326 location->objectid, root);
1327 if (ret) {
1328 kfree(root);
1329 return ERR_PTR(ret);
1330 }
1331 goto out;
1332 }
1333
1334 __setup_root(tree_root->nodesize, tree_root->leafsize,
1335 tree_root->sectorsize, tree_root->stripesize,
1336 root, fs_info, location->objectid);
1337
1338 path = btrfs_alloc_path();
1339 if (!path) {
1340 kfree(root);
1341 return ERR_PTR(-ENOMEM);
1342 }
1343 ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
1344 if (ret == 0) {
1345 l = path->nodes[0];
1346 read_extent_buffer(l, &root->root_item,
1347 btrfs_item_ptr_offset(l, path->slots[0]),
1348 sizeof(root->root_item));
1349 memcpy(&root->root_key, location, sizeof(*location));
1350 }
1351 btrfs_free_path(path);
1352 if (ret) {
1353 kfree(root);
1354 if (ret > 0)
1355 ret = -ENOENT;
1356 return ERR_PTR(ret);
1357 }
1358
1359 generation = btrfs_root_generation(&root->root_item);
1360 blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
1361 root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
1362 blocksize, generation);
1363 root->commit_root = btrfs_root_node(root);
1364 BUG_ON(!root->node);
1365 out:
1366 if (location->objectid != BTRFS_TREE_LOG_OBJECTID) {
1367 root->ref_cows = 1;
1368 btrfs_check_and_init_root_item(&root->root_item);
1369 }
1370
1371 return root;
1372 }
1373
1374 struct btrfs_root *btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
1375 struct btrfs_key *location)
1376 {
1377 struct btrfs_root *root;
1378 int ret;
1379
1380 if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
1381 return fs_info->tree_root;
1382 if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
1383 return fs_info->extent_root;
1384 if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
1385 return fs_info->chunk_root;
1386 if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
1387 return fs_info->dev_root;
1388 if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
1389 return fs_info->csum_root;
1390 again:
1391 spin_lock(&fs_info->fs_roots_radix_lock);
1392 root = radix_tree_lookup(&fs_info->fs_roots_radix,
1393 (unsigned long)location->objectid);
1394 spin_unlock(&fs_info->fs_roots_radix_lock);
1395 if (root)
1396 return root;
1397
1398 root = btrfs_read_fs_root_no_radix(fs_info->tree_root, location);
1399 if (IS_ERR(root))
1400 return root;
1401
1402 root->free_ino_ctl = kzalloc(sizeof(*root->free_ino_ctl), GFP_NOFS);
1403 root->free_ino_pinned = kzalloc(sizeof(*root->free_ino_pinned),
1404 GFP_NOFS);
1405 if (!root->free_ino_pinned || !root->free_ino_ctl) {
1406 ret = -ENOMEM;
1407 goto fail;
1408 }
1409
1410 btrfs_init_free_ino_ctl(root);
1411 mutex_init(&root->fs_commit_mutex);
1412 spin_lock_init(&root->cache_lock);
1413 init_waitqueue_head(&root->cache_wait);
1414
1415 ret = get_anon_bdev(&root->anon_dev);
1416 if (ret)
1417 goto fail;
1418
1419 if (btrfs_root_refs(&root->root_item) == 0) {
1420 ret = -ENOENT;
1421 goto fail;
1422 }
1423
1424 ret = btrfs_find_orphan_item(fs_info->tree_root, location->objectid);
1425 if (ret < 0)
1426 goto fail;
1427 if (ret == 0)
1428 root->orphan_item_inserted = 1;
1429
1430 ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
1431 if (ret)
1432 goto fail;
1433
1434 spin_lock(&fs_info->fs_roots_radix_lock);
1435 ret = radix_tree_insert(&fs_info->fs_roots_radix,
1436 (unsigned long)root->root_key.objectid,
1437 root);
1438 if (ret == 0)
1439 root->in_radix = 1;
1440
1441 spin_unlock(&fs_info->fs_roots_radix_lock);
1442 radix_tree_preload_end();
1443 if (ret) {
1444 if (ret == -EEXIST) {
1445 free_fs_root(root);
1446 goto again;
1447 }
1448 goto fail;
1449 }
1450
1451 ret = btrfs_find_dead_roots(fs_info->tree_root,
1452 root->root_key.objectid);
1453 WARN_ON(ret);
1454 return root;
1455 fail:
1456 free_fs_root(root);
1457 return ERR_PTR(ret);
1458 }
1459
1460 static int btrfs_congested_fn(void *congested_data, int bdi_bits)
1461 {
1462 struct btrfs_fs_info *info = (struct btrfs_fs_info *)congested_data;
1463 int ret = 0;
1464 struct btrfs_device *device;
1465 struct backing_dev_info *bdi;
1466
1467 rcu_read_lock();
1468 list_for_each_entry_rcu(device, &info->fs_devices->devices, dev_list) {
1469 if (!device->bdev)
1470 continue;
1471 bdi = blk_get_backing_dev_info(device->bdev);
1472 if (bdi && bdi_congested(bdi, bdi_bits)) {
1473 ret = 1;
1474 break;
1475 }
1476 }
1477 rcu_read_unlock();
1478 return ret;
1479 }
1480
1481 /*
1482 * If this fails, caller must call bdi_destroy() to get rid of the
1483 * bdi again.
1484 */
1485 static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi)
1486 {
1487 int err;
1488
1489 bdi->capabilities = BDI_CAP_MAP_COPY;
1490 err = bdi_setup_and_register(bdi, "btrfs", BDI_CAP_MAP_COPY);
1491 if (err)
1492 return err;
1493
1494 bdi->ra_pages = default_backing_dev_info.ra_pages;
1495 bdi->congested_fn = btrfs_congested_fn;
1496 bdi->congested_data = info;
1497 return 0;
1498 }
1499
1500 static int bio_ready_for_csum(struct bio *bio)
1501 {
1502 u64 length = 0;
1503 u64 buf_len = 0;
1504 u64 start = 0;
1505 struct page *page;
1506 struct extent_io_tree *io_tree = NULL;
1507 struct bio_vec *bvec;
1508 int i;
1509 int ret;
1510
1511 bio_for_each_segment(bvec, bio, i) {
1512 page = bvec->bv_page;
1513 if (page->private == EXTENT_PAGE_PRIVATE) {
1514 length += bvec->bv_len;
1515 continue;
1516 }
1517 if (!page->private) {
1518 length += bvec->bv_len;
1519 continue;
1520 }
1521 length = bvec->bv_len;
1522 buf_len = page->private >> 2;
1523 start = page_offset(page) + bvec->bv_offset;
1524 io_tree = &BTRFS_I(page->mapping->host)->io_tree;
1525 }
1526 /* are we fully contained in this bio? */
1527 if (buf_len <= length)
1528 return 1;
1529
1530 ret = extent_range_uptodate(io_tree, start + length,
1531 start + buf_len - 1);
1532 return ret;
1533 }
1534
1535 /*
1536 * called by the kthread helper functions to finally call the bio end_io
1537 * functions. This is where read checksum verification actually happens
1538 */
1539 static void end_workqueue_fn(struct btrfs_work *work)
1540 {
1541 struct bio *bio;
1542 struct end_io_wq *end_io_wq;
1543 struct btrfs_fs_info *fs_info;
1544 int error;
1545
1546 end_io_wq = container_of(work, struct end_io_wq, work);
1547 bio = end_io_wq->bio;
1548 fs_info = end_io_wq->info;
1549
1550 /* metadata bio reads are special because the whole tree block must
1551 * be checksummed at once. This makes sure the entire block is in
1552 * ram and up to date before trying to verify things. For
1553 * blocksize <= pagesize, it is basically a noop
1554 */
1555 if (!(bio->bi_rw & REQ_WRITE) && end_io_wq->metadata &&
1556 !bio_ready_for_csum(bio)) {
1557 btrfs_queue_worker(&fs_info->endio_meta_workers,
1558 &end_io_wq->work);
1559 return;
1560 }
1561 error = end_io_wq->error;
1562 bio->bi_private = end_io_wq->private;
1563 bio->bi_end_io = end_io_wq->end_io;
1564 kfree(end_io_wq);
1565 bio_endio(bio, error);
1566 }
1567
1568 static int cleaner_kthread(void *arg)
1569 {
1570 struct btrfs_root *root = arg;
1571
1572 do {
1573 vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
1574
1575 if (!(root->fs_info->sb->s_flags & MS_RDONLY) &&
1576 mutex_trylock(&root->fs_info->cleaner_mutex)) {
1577 btrfs_run_delayed_iputs(root);
1578 btrfs_clean_old_snapshots(root);
1579 mutex_unlock(&root->fs_info->cleaner_mutex);
1580 btrfs_run_defrag_inodes(root->fs_info);
1581 }
1582
1583 if (freezing(current)) {
1584 refrigerator();
1585 } else {
1586 set_current_state(TASK_INTERRUPTIBLE);
1587 if (!kthread_should_stop())
1588 schedule();
1589 __set_current_state(TASK_RUNNING);
1590 }
1591 } while (!kthread_should_stop());
1592 return 0;
1593 }
1594
1595 static int transaction_kthread(void *arg)
1596 {
1597 struct btrfs_root *root = arg;
1598 struct btrfs_trans_handle *trans;
1599 struct btrfs_transaction *cur;
1600 u64 transid;
1601 unsigned long now;
1602 unsigned long delay;
1603 int ret;
1604
1605 do {
1606 delay = HZ * 30;
1607 vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
1608 mutex_lock(&root->fs_info->transaction_kthread_mutex);
1609
1610 spin_lock(&root->fs_info->trans_lock);
1611 cur = root->fs_info->running_transaction;
1612 if (!cur) {
1613 spin_unlock(&root->fs_info->trans_lock);
1614 goto sleep;
1615 }
1616
1617 now = get_seconds();
1618 if (!cur->blocked &&
1619 (now < cur->start_time || now - cur->start_time < 30)) {
1620 spin_unlock(&root->fs_info->trans_lock);
1621 delay = HZ * 5;
1622 goto sleep;
1623 }
1624 transid = cur->transid;
1625 spin_unlock(&root->fs_info->trans_lock);
1626
1627 trans = btrfs_join_transaction(root);
1628 BUG_ON(IS_ERR(trans));
1629 if (transid == trans->transid) {
1630 ret = btrfs_commit_transaction(trans, root);
1631 BUG_ON(ret);
1632 } else {
1633 btrfs_end_transaction(trans, root);
1634 }
1635 sleep:
1636 wake_up_process(root->fs_info->cleaner_kthread);
1637 mutex_unlock(&root->fs_info->transaction_kthread_mutex);
1638
1639 if (freezing(current)) {
1640 refrigerator();
1641 } else {
1642 set_current_state(TASK_INTERRUPTIBLE);
1643 if (!kthread_should_stop() &&
1644 !btrfs_transaction_blocked(root->fs_info))
1645 schedule_timeout(delay);
1646 __set_current_state(TASK_RUNNING);
1647 }
1648 } while (!kthread_should_stop());
1649 return 0;
1650 }
1651
1652 /*
1653 * this will find the highest generation in the array of
1654 * root backups. The index of the highest array is returned,
1655 * or -1 if we can't find anything.
1656 *
1657 * We check to make sure the array is valid by comparing the
1658 * generation of the latest root in the array with the generation
1659 * in the super block. If they don't match we pitch it.
1660 */
1661 static int find_newest_super_backup(struct btrfs_fs_info *info, u64 newest_gen)
1662 {
1663 u64 cur;
1664 int newest_index = -1;
1665 struct btrfs_root_backup *root_backup;
1666 int i;
1667
1668 for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
1669 root_backup = info->super_copy->super_roots + i;
1670 cur = btrfs_backup_tree_root_gen(root_backup);
1671 if (cur == newest_gen)
1672 newest_index = i;
1673 }
1674
1675 /* check to see if we actually wrapped around */
1676 if (newest_index == BTRFS_NUM_BACKUP_ROOTS - 1) {
1677 root_backup = info->super_copy->super_roots;
1678 cur = btrfs_backup_tree_root_gen(root_backup);
1679 if (cur == newest_gen)
1680 newest_index = 0;
1681 }
1682 return newest_index;
1683 }
1684
1685
1686 /*
1687 * find the oldest backup so we know where to store new entries
1688 * in the backup array. This will set the backup_root_index
1689 * field in the fs_info struct
1690 */
1691 static void find_oldest_super_backup(struct btrfs_fs_info *info,
1692 u64 newest_gen)
1693 {
1694 int newest_index = -1;
1695
1696 newest_index = find_newest_super_backup(info, newest_gen);
1697 /* if there was garbage in there, just move along */
1698 if (newest_index == -1) {
1699 info->backup_root_index = 0;
1700 } else {
1701 info->backup_root_index = (newest_index + 1) % BTRFS_NUM_BACKUP_ROOTS;
1702 }
1703 }
1704
1705 /*
1706 * copy all the root pointers into the super backup array.
1707 * this will bump the backup pointer by one when it is
1708 * done
1709 */
1710 static void backup_super_roots(struct btrfs_fs_info *info)
1711 {
1712 int next_backup;
1713 struct btrfs_root_backup *root_backup;
1714 int last_backup;
1715
1716 next_backup = info->backup_root_index;
1717 last_backup = (next_backup + BTRFS_NUM_BACKUP_ROOTS - 1) %
1718 BTRFS_NUM_BACKUP_ROOTS;
1719
1720 /*
1721 * just overwrite the last backup if we're at the same generation
1722 * this happens only at umount
1723 */
1724 root_backup = info->super_for_commit->super_roots + last_backup;
1725 if (btrfs_backup_tree_root_gen(root_backup) ==
1726 btrfs_header_generation(info->tree_root->node))
1727 next_backup = last_backup;
1728
1729 root_backup = info->super_for_commit->super_roots + next_backup;
1730
1731 /*
1732 * make sure all of our padding and empty slots get zero filled
1733 * regardless of which ones we use today
1734 */
1735 memset(root_backup, 0, sizeof(*root_backup));
1736
1737 info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;
1738
1739 btrfs_set_backup_tree_root(root_backup, info->tree_root->node->start);
1740 btrfs_set_backup_tree_root_gen(root_backup,
1741 btrfs_header_generation(info->tree_root->node));
1742
1743 btrfs_set_backup_tree_root_level(root_backup,
1744 btrfs_header_level(info->tree_root->node));
1745
1746 btrfs_set_backup_chunk_root(root_backup, info->chunk_root->node->start);
1747 btrfs_set_backup_chunk_root_gen(root_backup,
1748 btrfs_header_generation(info->chunk_root->node));
1749 btrfs_set_backup_chunk_root_level(root_backup,
1750 btrfs_header_level(info->chunk_root->node));
1751
1752 btrfs_set_backup_extent_root(root_backup, info->extent_root->node->start);
1753 btrfs_set_backup_extent_root_gen(root_backup,
1754 btrfs_header_generation(info->extent_root->node));
1755 btrfs_set_backup_extent_root_level(root_backup,
1756 btrfs_header_level(info->extent_root->node));
1757
1758 /*
1759 * we might commit during log recovery, which happens before we set
1760 * the fs_root. Make sure it is valid before we fill it in.
1761 */
1762 if (info->fs_root && info->fs_root->node) {
1763 btrfs_set_backup_fs_root(root_backup,
1764 info->fs_root->node->start);
1765 btrfs_set_backup_fs_root_gen(root_backup,
1766 btrfs_header_generation(info->fs_root->node));
1767 btrfs_set_backup_fs_root_level(root_backup,
1768 btrfs_header_level(info->fs_root->node));
1769 }
1770
1771 btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start);
1772 btrfs_set_backup_dev_root_gen(root_backup,
1773 btrfs_header_generation(info->dev_root->node));
1774 btrfs_set_backup_dev_root_level(root_backup,
1775 btrfs_header_level(info->dev_root->node));
1776
1777 btrfs_set_backup_csum_root(root_backup, info->csum_root->node->start);
1778 btrfs_set_backup_csum_root_gen(root_backup,
1779 btrfs_header_generation(info->csum_root->node));
1780 btrfs_set_backup_csum_root_level(root_backup,
1781 btrfs_header_level(info->csum_root->node));
1782
1783 btrfs_set_backup_total_bytes(root_backup,
1784 btrfs_super_total_bytes(info->super_copy));
1785 btrfs_set_backup_bytes_used(root_backup,
1786 btrfs_super_bytes_used(info->super_copy));
1787 btrfs_set_backup_num_devices(root_backup,
1788 btrfs_super_num_devices(info->super_copy));
1789
1790 /*
1791 * if we don't copy this out to the super_copy, it won't get remembered
1792 * for the next commit
1793 */
1794 memcpy(&info->super_copy->super_roots,
1795 &info->super_for_commit->super_roots,
1796 sizeof(*root_backup) * BTRFS_NUM_BACKUP_ROOTS);
1797 }
1798
1799 /*
1800 * this copies info out of the root backup array and back into
1801 * the in-memory super block. It is meant to help iterate through
1802 * the array, so you send it the number of backups you've already
1803 * tried and the last backup index you used.
1804 *
1805 * this returns -1 when it has tried all the backups
1806 */
1807 static noinline int next_root_backup(struct btrfs_fs_info *info,
1808 struct btrfs_super_block *super,
1809 int *num_backups_tried, int *backup_index)
1810 {
1811 struct btrfs_root_backup *root_backup;
1812 int newest = *backup_index;
1813
1814 if (*num_backups_tried == 0) {
1815 u64 gen = btrfs_super_generation(super);
1816
1817 newest = find_newest_super_backup(info, gen);
1818 if (newest == -1)
1819 return -1;
1820
1821 *backup_index = newest;
1822 *num_backups_tried = 1;
1823 } else if (*num_backups_tried == BTRFS_NUM_BACKUP_ROOTS) {
1824 /* we've tried all the backups, all done */
1825 return -1;
1826 } else {
1827 /* jump to the next oldest backup */
1828 newest = (*backup_index + BTRFS_NUM_BACKUP_ROOTS - 1) %
1829 BTRFS_NUM_BACKUP_ROOTS;
1830 *backup_index = newest;
1831 *num_backups_tried += 1;
1832 }
1833 root_backup = super->super_roots + newest;
1834
1835 btrfs_set_super_generation(super,
1836 btrfs_backup_tree_root_gen(root_backup));
1837 btrfs_set_super_root(super, btrfs_backup_tree_root(root_backup));
1838 btrfs_set_super_root_level(super,
1839 btrfs_backup_tree_root_level(root_backup));
1840 btrfs_set_super_bytes_used(super, btrfs_backup_bytes_used(root_backup));
1841
1842 /*
1843 * fixme: the total bytes and num_devices need to match or we should
1844 * need a fsck
1845 */
1846 btrfs_set_super_total_bytes(super, btrfs_backup_total_bytes(root_backup));
1847 btrfs_set_super_num_devices(super, btrfs_backup_num_devices(root_backup));
1848 return 0;
1849 }
1850
1851 /* helper to cleanup tree roots */
1852 static void free_root_pointers(struct btrfs_fs_info *info, int chunk_root)
1853 {
1854 free_extent_buffer(info->tree_root->node);
1855 free_extent_buffer(info->tree_root->commit_root);
1856 free_extent_buffer(info->dev_root->node);
1857 free_extent_buffer(info->dev_root->commit_root);
1858 free_extent_buffer(info->extent_root->node);
1859 free_extent_buffer(info->extent_root->commit_root);
1860 free_extent_buffer(info->csum_root->node);
1861 free_extent_buffer(info->csum_root->commit_root);
1862
1863 info->tree_root->node = NULL;
1864 info->tree_root->commit_root = NULL;
1865 info->dev_root->node = NULL;
1866 info->dev_root->commit_root = NULL;
1867 info->extent_root->node = NULL;
1868 info->extent_root->commit_root = NULL;
1869 info->csum_root->node = NULL;
1870 info->csum_root->commit_root = NULL;
1871
1872 if (chunk_root) {
1873 free_extent_buffer(info->chunk_root->node);
1874 free_extent_buffer(info->chunk_root->commit_root);
1875 info->chunk_root->node = NULL;
1876 info->chunk_root->commit_root = NULL;
1877 }
1878 }
1879
1880
1881 struct btrfs_root *open_ctree(struct super_block *sb,
1882 struct btrfs_fs_devices *fs_devices,
1883 char *options)
1884 {
1885 u32 sectorsize;
1886 u32 nodesize;
1887 u32 leafsize;
1888 u32 blocksize;
1889 u32 stripesize;
1890 u64 generation;
1891 u64 features;
1892 struct btrfs_key location;
1893 struct buffer_head *bh;
1894 struct btrfs_super_block *disk_super;
1895 struct btrfs_root *tree_root = btrfs_sb(sb);
1896 struct btrfs_fs_info *fs_info = tree_root->fs_info;
1897 struct btrfs_root *extent_root;
1898 struct btrfs_root *csum_root;
1899 struct btrfs_root *chunk_root;
1900 struct btrfs_root *dev_root;
1901 struct btrfs_root *log_tree_root;
1902 int ret;
1903 int err = -EINVAL;
1904 int num_backups_tried = 0;
1905 int backup_index = 0;
1906
1907 extent_root = fs_info->extent_root =
1908 kzalloc(sizeof(struct btrfs_root), GFP_NOFS);
1909 csum_root = fs_info->csum_root =
1910 kzalloc(sizeof(struct btrfs_root), GFP_NOFS);
1911 chunk_root = fs_info->chunk_root =
1912 kzalloc(sizeof(struct btrfs_root), GFP_NOFS);
1913 dev_root = fs_info->dev_root =
1914 kzalloc(sizeof(struct btrfs_root), GFP_NOFS);
1915
1916 if (!extent_root || !csum_root || !chunk_root || !dev_root) {
1917 err = -ENOMEM;
1918 goto fail;
1919 }
1920
1921 ret = init_srcu_struct(&fs_info->subvol_srcu);
1922 if (ret) {
1923 err = ret;
1924 goto fail;
1925 }
1926
1927 ret = setup_bdi(fs_info, &fs_info->bdi);
1928 if (ret) {
1929 err = ret;
1930 goto fail_srcu;
1931 }
1932
1933 fs_info->btree_inode = new_inode(sb);
1934 if (!fs_info->btree_inode) {
1935 err = -ENOMEM;
1936 goto fail_bdi;
1937 }
1938
1939 mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
1940
1941 INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
1942 INIT_LIST_HEAD(&fs_info->trans_list);
1943 INIT_LIST_HEAD(&fs_info->dead_roots);
1944 INIT_LIST_HEAD(&fs_info->delayed_iputs);
1945 INIT_LIST_HEAD(&fs_info->hashers);
1946 INIT_LIST_HEAD(&fs_info->delalloc_inodes);
1947 INIT_LIST_HEAD(&fs_info->ordered_operations);
1948 INIT_LIST_HEAD(&fs_info->caching_block_groups);
1949 spin_lock_init(&fs_info->delalloc_lock);
1950 spin_lock_init(&fs_info->trans_lock);
1951 spin_lock_init(&fs_info->ref_cache_lock);
1952 spin_lock_init(&fs_info->fs_roots_radix_lock);
1953 spin_lock_init(&fs_info->delayed_iput_lock);
1954 spin_lock_init(&fs_info->defrag_inodes_lock);
1955 spin_lock_init(&fs_info->free_chunk_lock);
1956 mutex_init(&fs_info->reloc_mutex);
1957
1958 init_completion(&fs_info->kobj_unregister);
1959 INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
1960 INIT_LIST_HEAD(&fs_info->space_info);
1961 btrfs_mapping_init(&fs_info->mapping_tree);
1962 btrfs_init_block_rsv(&fs_info->global_block_rsv);
1963 btrfs_init_block_rsv(&fs_info->delalloc_block_rsv);
1964 btrfs_init_block_rsv(&fs_info->trans_block_rsv);
1965 btrfs_init_block_rsv(&fs_info->chunk_block_rsv);
1966 btrfs_init_block_rsv(&fs_info->empty_block_rsv);
1967 btrfs_init_block_rsv(&fs_info->delayed_block_rsv);
1968 atomic_set(&fs_info->nr_async_submits, 0);
1969 atomic_set(&fs_info->async_delalloc_pages, 0);
1970 atomic_set(&fs_info->async_submit_draining, 0);
1971 atomic_set(&fs_info->nr_async_bios, 0);
1972 atomic_set(&fs_info->defrag_running, 0);
1973 fs_info->sb = sb;
1974 fs_info->max_inline = 8192 * 1024;
1975 fs_info->metadata_ratio = 0;
1976 fs_info->defrag_inodes = RB_ROOT;
1977 fs_info->trans_no_join = 0;
1978 fs_info->free_chunk_space = 0;
1979
1980 /* readahead state */
1981 INIT_RADIX_TREE(&fs_info->reada_tree, GFP_NOFS & ~__GFP_WAIT);
1982 spin_lock_init(&fs_info->reada_lock);
1983
1984 fs_info->thread_pool_size = min_t(unsigned long,
1985 num_online_cpus() + 2, 8);
1986
1987 INIT_LIST_HEAD(&fs_info->ordered_extents);
1988 spin_lock_init(&fs_info->ordered_extent_lock);
1989 fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root),
1990 GFP_NOFS);
1991 if (!fs_info->delayed_root) {
1992 err = -ENOMEM;
1993 goto fail_iput;
1994 }
1995 btrfs_init_delayed_root(fs_info->delayed_root);
1996
1997 mutex_init(&fs_info->scrub_lock);
1998 atomic_set(&fs_info->scrubs_running, 0);
1999 atomic_set(&fs_info->scrub_pause_req, 0);
2000 atomic_set(&fs_info->scrubs_paused, 0);
2001 atomic_set(&fs_info->scrub_cancel_req, 0);
2002 init_waitqueue_head(&fs_info->scrub_pause_wait);
2003 init_rwsem(&fs_info->scrub_super_lock);
2004 fs_info->scrub_workers_refcnt = 0;
2005
2006 sb->s_blocksize = 4096;
2007 sb->s_blocksize_bits = blksize_bits(4096);
2008 sb->s_bdi = &fs_info->bdi;
2009
2010 fs_info->btree_inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
2011 set_nlink(fs_info->btree_inode, 1);
2012 /*
2013 * we set the i_size on the btree inode to the max possible int.
2014 * the real end of the address space is determined by all of
2015 * the devices in the system
2016 */
2017 fs_info->btree_inode->i_size = OFFSET_MAX;
2018 fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
2019 fs_info->btree_inode->i_mapping->backing_dev_info = &fs_info->bdi;
2020
2021 RB_CLEAR_NODE(&BTRFS_I(fs_info->btree_inode)->rb_node);
2022 extent_io_tree_init(&BTRFS_I(fs_info->btree_inode)->io_tree,
2023 fs_info->btree_inode->i_mapping);
2024 extent_map_tree_init(&BTRFS_I(fs_info->btree_inode)->extent_tree);
2025
2026 BTRFS_I(fs_info->btree_inode)->io_tree.ops = &btree_extent_io_ops;
2027
2028 BTRFS_I(fs_info->btree_inode)->root = tree_root;
2029 memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
2030 sizeof(struct btrfs_key));
2031 BTRFS_I(fs_info->btree_inode)->dummy_inode = 1;
2032 insert_inode_hash(fs_info->btree_inode);
2033
2034 spin_lock_init(&fs_info->block_group_cache_lock);
2035 fs_info->block_group_cache_tree = RB_ROOT;
2036
2037 extent_io_tree_init(&fs_info->freed_extents[0],
2038 fs_info->btree_inode->i_mapping);
2039 extent_io_tree_init(&fs_info->freed_extents[1],
2040 fs_info->btree_inode->i_mapping);
2041 fs_info->pinned_extents = &fs_info->freed_extents[0];
2042 fs_info->do_barriers = 1;
2043
2044
2045 mutex_init(&fs_info->ordered_operations_mutex);
2046 mutex_init(&fs_info->tree_log_mutex);
2047 mutex_init(&fs_info->chunk_mutex);
2048 mutex_init(&fs_info->transaction_kthread_mutex);
2049 mutex_init(&fs_info->cleaner_mutex);
2050 mutex_init(&fs_info->volume_mutex);
2051 init_rwsem(&fs_info->extent_commit_sem);
2052 init_rwsem(&fs_info->cleanup_work_sem);
2053 init_rwsem(&fs_info->subvol_sem);
2054
2055 btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
2056 btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
2057
2058 init_waitqueue_head(&fs_info->transaction_throttle);
2059 init_waitqueue_head(&fs_info->transaction_wait);
2060 init_waitqueue_head(&fs_info->transaction_blocked_wait);
2061 init_waitqueue_head(&fs_info->async_submit_wait);
2062
2063 __setup_root(4096, 4096, 4096, 4096, tree_root,
2064 fs_info, BTRFS_ROOT_TREE_OBJECTID);
2065
2066 bh = btrfs_read_dev_super(fs_devices->latest_bdev);
2067 if (!bh) {
2068 err = -EINVAL;
2069 goto fail_alloc;
2070 }
2071
2072 memcpy(fs_info->super_copy, bh->b_data, sizeof(*fs_info->super_copy));
2073 memcpy(fs_info->super_for_commit, fs_info->super_copy,
2074 sizeof(*fs_info->super_for_commit));
2075 brelse(bh);
2076
2077 memcpy(fs_info->fsid, fs_info->super_copy->fsid, BTRFS_FSID_SIZE);
2078
2079 disk_super = fs_info->super_copy;
2080 if (!btrfs_super_root(disk_super))
2081 goto fail_alloc;
2082
2083 /* check FS state, whether FS is broken. */
2084 fs_info->fs_state |= btrfs_super_flags(disk_super);
2085
2086 btrfs_check_super_valid(fs_info, sb->s_flags & MS_RDONLY);
2087
2088 /*
2089 * run through our array of backup supers and setup
2090 * our ring pointer to the oldest one
2091 */
2092 generation = btrfs_super_generation(disk_super);
2093 find_oldest_super_backup(fs_info, generation);
2094
2095 /*
2096 * In the long term, we'll store the compression type in the super
2097 * block, and it'll be used for per file compression control.
2098 */
2099 fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
2100
2101 ret = btrfs_parse_options(tree_root, options);
2102 if (ret) {
2103 err = ret;
2104 goto fail_alloc;
2105 }
2106
2107 features = btrfs_super_incompat_flags(disk_super) &
2108 ~BTRFS_FEATURE_INCOMPAT_SUPP;
2109 if (features) {
2110 printk(KERN_ERR "BTRFS: couldn't mount because of "
2111 "unsupported optional features (%Lx).\n",
2112 (unsigned long long)features);
2113 err = -EINVAL;
2114 goto fail_alloc;
2115 }
2116
2117 features = btrfs_super_incompat_flags(disk_super);
2118 features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
2119 if (tree_root->fs_info->compress_type & BTRFS_COMPRESS_LZO)
2120 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
2121 btrfs_set_super_incompat_flags(disk_super, features);
2122
2123 features = btrfs_super_compat_ro_flags(disk_super) &
2124 ~BTRFS_FEATURE_COMPAT_RO_SUPP;
2125 if (!(sb->s_flags & MS_RDONLY) && features) {
2126 printk(KERN_ERR "BTRFS: couldn't mount RDWR because of "
2127 "unsupported option features (%Lx).\n",
2128 (unsigned long long)features);
2129 err = -EINVAL;
2130 goto fail_alloc;
2131 }
2132
2133 btrfs_init_workers(&fs_info->generic_worker,
2134 "genwork", 1, NULL);
2135
2136 btrfs_init_workers(&fs_info->workers, "worker",
2137 fs_info->thread_pool_size,
2138 &fs_info->generic_worker);
2139
2140 btrfs_init_workers(&fs_info->delalloc_workers, "delalloc",
2141 fs_info->thread_pool_size,
2142 &fs_info->generic_worker);
2143
2144 btrfs_init_workers(&fs_info->submit_workers, "submit",
2145 min_t(u64, fs_devices->num_devices,
2146 fs_info->thread_pool_size),
2147 &fs_info->generic_worker);
2148
2149 btrfs_init_workers(&fs_info->caching_workers, "cache",
2150 2, &fs_info->generic_worker);
2151
2152 /* a higher idle thresh on the submit workers makes it much more
2153 * likely that bios will be send down in a sane order to the
2154 * devices
2155 */
2156 fs_info->submit_workers.idle_thresh = 64;
2157
2158 fs_info->workers.idle_thresh = 16;
2159 fs_info->workers.ordered = 1;
2160
2161 fs_info->delalloc_workers.idle_thresh = 2;
2162 fs_info->delalloc_workers.ordered = 1;
2163
2164 btrfs_init_workers(&fs_info->fixup_workers, "fixup", 1,
2165 &fs_info->generic_worker);
2166 btrfs_init_workers(&fs_info->endio_workers, "endio",
2167 fs_info->thread_pool_size,
2168 &fs_info->generic_worker);
2169 btrfs_init_workers(&fs_info->endio_meta_workers, "endio-meta",
2170 fs_info->thread_pool_size,
2171 &fs_info->generic_worker);
2172 btrfs_init_workers(&fs_info->endio_meta_write_workers,
2173 "endio-meta-write", fs_info->thread_pool_size,
2174 &fs_info->generic_worker);
2175 btrfs_init_workers(&fs_info->endio_write_workers, "endio-write",
2176 fs_info->thread_pool_size,
2177 &fs_info->generic_worker);
2178 btrfs_init_workers(&fs_info->endio_freespace_worker, "freespace-write",
2179 1, &fs_info->generic_worker);
2180 btrfs_init_workers(&fs_info->delayed_workers, "delayed-meta",
2181 fs_info->thread_pool_size,
2182 &fs_info->generic_worker);
2183 btrfs_init_workers(&fs_info->readahead_workers, "readahead",
2184 fs_info->thread_pool_size,
2185 &fs_info->generic_worker);
2186
2187 /*
2188 * endios are largely parallel and should have a very
2189 * low idle thresh
2190 */
2191 fs_info->endio_workers.idle_thresh = 4;
2192 fs_info->endio_meta_workers.idle_thresh = 4;
2193
2194 fs_info->endio_write_workers.idle_thresh = 2;
2195 fs_info->endio_meta_write_workers.idle_thresh = 2;
2196 fs_info->readahead_workers.idle_thresh = 2;
2197
2198 /*
2199 * btrfs_start_workers can really only fail because of ENOMEM so just
2200 * return -ENOMEM if any of these fail.
2201 */
2202 ret = btrfs_start_workers(&fs_info->workers);
2203 ret |= btrfs_start_workers(&fs_info->generic_worker);
2204 ret |= btrfs_start_workers(&fs_info->submit_workers);
2205 ret |= btrfs_start_workers(&fs_info->delalloc_workers);
2206 ret |= btrfs_start_workers(&fs_info->fixup_workers);
2207 ret |= btrfs_start_workers(&fs_info->endio_workers);
2208 ret |= btrfs_start_workers(&fs_info->endio_meta_workers);
2209 ret |= btrfs_start_workers(&fs_info->endio_meta_write_workers);
2210 ret |= btrfs_start_workers(&fs_info->endio_write_workers);
2211 ret |= btrfs_start_workers(&fs_info->endio_freespace_worker);
2212 ret |= btrfs_start_workers(&fs_info->delayed_workers);
2213 ret |= btrfs_start_workers(&fs_info->caching_workers);
2214 ret |= btrfs_start_workers(&fs_info->readahead_workers);
2215 if (ret) {
2216 ret = -ENOMEM;
2217 goto fail_sb_buffer;
2218 }
2219
2220 fs_info->bdi.ra_pages *= btrfs_super_num_devices(disk_super);
2221 fs_info->bdi.ra_pages = max(fs_info->bdi.ra_pages,
2222 4 * 1024 * 1024 / PAGE_CACHE_SIZE);
2223
2224 nodesize = btrfs_super_nodesize(disk_super);
2225 leafsize = btrfs_super_leafsize(disk_super);
2226 sectorsize = btrfs_super_sectorsize(disk_super);
2227 stripesize = btrfs_super_stripesize(disk_super);
2228 tree_root->nodesize = nodesize;
2229 tree_root->leafsize = leafsize;
2230 tree_root->sectorsize = sectorsize;
2231 tree_root->stripesize = stripesize;
2232
2233 sb->s_blocksize = sectorsize;
2234 sb->s_blocksize_bits = blksize_bits(sectorsize);
2235
2236 if (strncmp((char *)(&disk_super->magic), BTRFS_MAGIC,
2237 sizeof(disk_super->magic))) {
2238 printk(KERN_INFO "btrfs: valid FS not found on %s\n", sb->s_id);
2239 goto fail_sb_buffer;
2240 }
2241
2242 mutex_lock(&fs_info->chunk_mutex);
2243 ret = btrfs_read_sys_array(tree_root);
2244 mutex_unlock(&fs_info->chunk_mutex);
2245 if (ret) {
2246 printk(KERN_WARNING "btrfs: failed to read the system "
2247 "array on %s\n", sb->s_id);
2248 goto fail_sb_buffer;
2249 }
2250
2251 blocksize = btrfs_level_size(tree_root,
2252 btrfs_super_chunk_root_level(disk_super));
2253 generation = btrfs_super_chunk_root_generation(disk_super);
2254
2255 __setup_root(nodesize, leafsize, sectorsize, stripesize,
2256 chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
2257
2258 chunk_root->node = read_tree_block(chunk_root,
2259 btrfs_super_chunk_root(disk_super),
2260 blocksize, generation);
2261 BUG_ON(!chunk_root->node);
2262 if (!test_bit(EXTENT_BUFFER_UPTODATE, &chunk_root->node->bflags)) {
2263 printk(KERN_WARNING "btrfs: failed to read chunk root on %s\n",
2264 sb->s_id);
2265 goto fail_tree_roots;
2266 }
2267 btrfs_set_root_node(&chunk_root->root_item, chunk_root->node);
2268 chunk_root->commit_root = btrfs_root_node(chunk_root);
2269
2270 read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
2271 (unsigned long)btrfs_header_chunk_tree_uuid(chunk_root->node),
2272 BTRFS_UUID_SIZE);
2273
2274 mutex_lock(&fs_info->chunk_mutex);
2275 ret = btrfs_read_chunk_tree(chunk_root);
2276 mutex_unlock(&fs_info->chunk_mutex);
2277 if (ret) {
2278 printk(KERN_WARNING "btrfs: failed to read chunk tree on %s\n",
2279 sb->s_id);
2280 goto fail_tree_roots;
2281 }
2282
2283 btrfs_close_extra_devices(fs_devices);
2284
2285 retry_root_backup:
2286 blocksize = btrfs_level_size(tree_root,
2287 btrfs_super_root_level(disk_super));
2288 generation = btrfs_super_generation(disk_super);
2289
2290 tree_root->node = read_tree_block(tree_root,
2291 btrfs_super_root(disk_super),
2292 blocksize, generation);
2293 if (!tree_root->node ||
2294 !test_bit(EXTENT_BUFFER_UPTODATE, &tree_root->node->bflags)) {
2295 printk(KERN_WARNING "btrfs: failed to read tree root on %s\n",
2296 sb->s_id);
2297
2298 goto recovery_tree_root;
2299 }
2300
2301 btrfs_set_root_node(&tree_root->root_item, tree_root->node);
2302 tree_root->commit_root = btrfs_root_node(tree_root);
2303
2304 ret = find_and_setup_root(tree_root, fs_info,
2305 BTRFS_EXTENT_TREE_OBJECTID, extent_root);
2306 if (ret)
2307 goto recovery_tree_root;
2308 extent_root->track_dirty = 1;
2309
2310 ret = find_and_setup_root(tree_root, fs_info,
2311 BTRFS_DEV_TREE_OBJECTID, dev_root);
2312 if (ret)
2313 goto recovery_tree_root;
2314 dev_root->track_dirty = 1;
2315
2316 ret = find_and_setup_root(tree_root, fs_info,
2317 BTRFS_CSUM_TREE_OBJECTID, csum_root);
2318 if (ret)
2319 goto recovery_tree_root;
2320
2321 csum_root->track_dirty = 1;
2322
2323 fs_info->generation = generation;
2324 fs_info->last_trans_committed = generation;
2325 fs_info->data_alloc_profile = (u64)-1;
2326 fs_info->metadata_alloc_profile = (u64)-1;
2327 fs_info->system_alloc_profile = fs_info->metadata_alloc_profile;
2328
2329 ret = btrfs_init_space_info(fs_info);
2330 if (ret) {
2331 printk(KERN_ERR "Failed to initial space info: %d\n", ret);
2332 goto fail_block_groups;
2333 }
2334
2335 ret = btrfs_read_block_groups(extent_root);
2336 if (ret) {
2337 printk(KERN_ERR "Failed to read block groups: %d\n", ret);
2338 goto fail_block_groups;
2339 }
2340
2341 fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root,
2342 "btrfs-cleaner");
2343 if (IS_ERR(fs_info->cleaner_kthread))
2344 goto fail_block_groups;
2345
2346 fs_info->transaction_kthread = kthread_run(transaction_kthread,
2347 tree_root,
2348 "btrfs-transaction");
2349 if (IS_ERR(fs_info->transaction_kthread))
2350 goto fail_cleaner;
2351
2352 if (!btrfs_test_opt(tree_root, SSD) &&
2353 !btrfs_test_opt(tree_root, NOSSD) &&
2354 !fs_info->fs_devices->rotating) {
2355 printk(KERN_INFO "Btrfs detected SSD devices, enabling SSD "
2356 "mode\n");
2357 btrfs_set_opt(fs_info->mount_opt, SSD);
2358 }
2359
2360 /* do not make disk changes in broken FS */
2361 if (btrfs_super_log_root(disk_super) != 0 &&
2362 !(fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)) {
2363 u64 bytenr = btrfs_super_log_root(disk_super);
2364
2365 if (fs_devices->rw_devices == 0) {
2366 printk(KERN_WARNING "Btrfs log replay required "
2367 "on RO media\n");
2368 err = -EIO;
2369 goto fail_trans_kthread;
2370 }
2371 blocksize =
2372 btrfs_level_size(tree_root,
2373 btrfs_super_log_root_level(disk_super));
2374
2375 log_tree_root = kzalloc(sizeof(struct btrfs_root), GFP_NOFS);
2376 if (!log_tree_root) {
2377 err = -ENOMEM;
2378 goto fail_trans_kthread;
2379 }
2380
2381 __setup_root(nodesize, leafsize, sectorsize, stripesize,
2382 log_tree_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
2383
2384 log_tree_root->node = read_tree_block(tree_root, bytenr,
2385 blocksize,
2386 generation + 1);
2387 ret = btrfs_recover_log_trees(log_tree_root);
2388 BUG_ON(ret);
2389
2390 if (sb->s_flags & MS_RDONLY) {
2391 ret = btrfs_commit_super(tree_root);
2392 BUG_ON(ret);
2393 }
2394 }
2395
2396 ret = btrfs_find_orphan_roots(tree_root);
2397 BUG_ON(ret);
2398
2399 if (!(sb->s_flags & MS_RDONLY)) {
2400 ret = btrfs_cleanup_fs_roots(fs_info);
2401 BUG_ON(ret);
2402
2403 ret = btrfs_recover_relocation(tree_root);
2404 if (ret < 0) {
2405 printk(KERN_WARNING
2406 "btrfs: failed to recover relocation\n");
2407 err = -EINVAL;
2408 goto fail_trans_kthread;
2409 }
2410 }
2411
2412 location.objectid = BTRFS_FS_TREE_OBJECTID;
2413 location.type = BTRFS_ROOT_ITEM_KEY;
2414 location.offset = (u64)-1;
2415
2416 fs_info->fs_root = btrfs_read_fs_root_no_name(fs_info, &location);
2417 if (!fs_info->fs_root)
2418 goto fail_trans_kthread;
2419 if (IS_ERR(fs_info->fs_root)) {
2420 err = PTR_ERR(fs_info->fs_root);
2421 goto fail_trans_kthread;
2422 }
2423
2424 if (!(sb->s_flags & MS_RDONLY)) {
2425 down_read(&fs_info->cleanup_work_sem);
2426 err = btrfs_orphan_cleanup(fs_info->fs_root);
2427 if (!err)
2428 err = btrfs_orphan_cleanup(fs_info->tree_root);
2429 up_read(&fs_info->cleanup_work_sem);
2430 if (err) {
2431 close_ctree(tree_root);
2432 return ERR_PTR(err);
2433 }
2434 }
2435
2436 return tree_root;
2437
2438 fail_trans_kthread:
2439 kthread_stop(fs_info->transaction_kthread);
2440 fail_cleaner:
2441 kthread_stop(fs_info->cleaner_kthread);
2442
2443 /*
2444 * make sure we're done with the btree inode before we stop our
2445 * kthreads
2446 */
2447 filemap_write_and_wait(fs_info->btree_inode->i_mapping);
2448 invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
2449
2450 fail_block_groups:
2451 btrfs_free_block_groups(fs_info);
2452
2453 fail_tree_roots:
2454 free_root_pointers(fs_info, 1);
2455
2456 fail_sb_buffer:
2457 btrfs_stop_workers(&fs_info->generic_worker);
2458 btrfs_stop_workers(&fs_info->readahead_workers);
2459 btrfs_stop_workers(&fs_info->fixup_workers);
2460 btrfs_stop_workers(&fs_info->delalloc_workers);
2461 btrfs_stop_workers(&fs_info->workers);
2462 btrfs_stop_workers(&fs_info->endio_workers);
2463 btrfs_stop_workers(&fs_info->endio_meta_workers);
2464 btrfs_stop_workers(&fs_info->endio_meta_write_workers);
2465 btrfs_stop_workers(&fs_info->endio_write_workers);
2466 btrfs_stop_workers(&fs_info->endio_freespace_worker);
2467 btrfs_stop_workers(&fs_info->submit_workers);
2468 btrfs_stop_workers(&fs_info->delayed_workers);
2469 btrfs_stop_workers(&fs_info->caching_workers);
2470 fail_alloc:
2471 fail_iput:
2472 btrfs_mapping_tree_free(&fs_info->mapping_tree);
2473
2474 invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
2475 iput(fs_info->btree_inode);
2476 fail_bdi:
2477 bdi_destroy(&fs_info->bdi);
2478 fail_srcu:
2479 cleanup_srcu_struct(&fs_info->subvol_srcu);
2480 fail:
2481 btrfs_close_devices(fs_info->fs_devices);
2482 free_fs_info(fs_info);
2483 return ERR_PTR(err);
2484
2485 recovery_tree_root:
2486 if (!btrfs_test_opt(tree_root, RECOVERY))
2487 goto fail_tree_roots;
2488
2489 free_root_pointers(fs_info, 0);
2490
2491 /* don't use the log in recovery mode, it won't be valid */
2492 btrfs_set_super_log_root(disk_super, 0);
2493
2494 /* we can't trust the free space cache either */
2495 btrfs_set_opt(fs_info->mount_opt, CLEAR_CACHE);
2496
2497 ret = next_root_backup(fs_info, fs_info->super_copy,
2498 &num_backups_tried, &backup_index);
2499 if (ret == -1)
2500 goto fail_block_groups;
2501 goto retry_root_backup;
2502 }
2503
2504 static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate)
2505 {
2506 char b[BDEVNAME_SIZE];
2507
2508 if (uptodate) {
2509 set_buffer_uptodate(bh);
2510 } else {
2511 printk_ratelimited(KERN_WARNING "lost page write due to "
2512 "I/O error on %s\n",
2513 bdevname(bh->b_bdev, b));
2514 /* note, we dont' set_buffer_write_io_error because we have
2515 * our own ways of dealing with the IO errors
2516 */
2517 clear_buffer_uptodate(bh);
2518 }
2519 unlock_buffer(bh);
2520 put_bh(bh);
2521 }
2522
2523 struct buffer_head *btrfs_read_dev_super(struct block_device *bdev)
2524 {
2525 struct buffer_head *bh;
2526 struct buffer_head *latest = NULL;
2527 struct btrfs_super_block *super;
2528 int i;
2529 u64 transid = 0;
2530 u64 bytenr;
2531
2532 /* we would like to check all the supers, but that would make
2533 * a btrfs mount succeed after a mkfs from a different FS.
2534 * So, we need to add a special mount option to scan for
2535 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
2536 */
2537 for (i = 0; i < 1; i++) {
2538 bytenr = btrfs_sb_offset(i);
2539 if (bytenr + 4096 >= i_size_read(bdev->bd_inode))
2540 break;
2541 bh = __bread(bdev, bytenr / 4096, 4096);
2542 if (!bh)
2543 continue;
2544
2545 super = (struct btrfs_super_block *)bh->b_data;
2546 if (btrfs_super_bytenr(super) != bytenr ||
2547 strncmp((char *)(&super->magic), BTRFS_MAGIC,
2548 sizeof(super->magic))) {
2549 brelse(bh);
2550 continue;
2551 }
2552
2553 if (!latest || btrfs_super_generation(super) > transid) {
2554 brelse(latest);
2555 latest = bh;
2556 transid = btrfs_super_generation(super);
2557 } else {
2558 brelse(bh);
2559 }
2560 }
2561 return latest;
2562 }
2563
2564 /*
2565 * this should be called twice, once with wait == 0 and
2566 * once with wait == 1. When wait == 0 is done, all the buffer heads
2567 * we write are pinned.
2568 *
2569 * They are released when wait == 1 is done.
2570 * max_mirrors must be the same for both runs, and it indicates how
2571 * many supers on this one device should be written.
2572 *
2573 * max_mirrors == 0 means to write them all.
2574 */
2575 static int write_dev_supers(struct btrfs_device *device,
2576 struct btrfs_super_block *sb,
2577 int do_barriers, int wait, int max_mirrors)
2578 {
2579 struct buffer_head *bh;
2580 int i;
2581 int ret;
2582 int errors = 0;
2583 u32 crc;
2584 u64 bytenr;
2585
2586 if (max_mirrors == 0)
2587 max_mirrors = BTRFS_SUPER_MIRROR_MAX;
2588
2589 for (i = 0; i < max_mirrors; i++) {
2590 bytenr = btrfs_sb_offset(i);
2591 if (bytenr + BTRFS_SUPER_INFO_SIZE >= device->total_bytes)
2592 break;
2593
2594 if (wait) {
2595 bh = __find_get_block(device->bdev, bytenr / 4096,
2596 BTRFS_SUPER_INFO_SIZE);
2597 BUG_ON(!bh);
2598 wait_on_buffer(bh);
2599 if (!buffer_uptodate(bh))
2600 errors++;
2601
2602 /* drop our reference */
2603 brelse(bh);
2604
2605 /* drop the reference from the wait == 0 run */
2606 brelse(bh);
2607 continue;
2608 } else {
2609 btrfs_set_super_bytenr(sb, bytenr);
2610
2611 crc = ~(u32)0;
2612 crc = btrfs_csum_data(NULL, (char *)sb +
2613 BTRFS_CSUM_SIZE, crc,
2614 BTRFS_SUPER_INFO_SIZE -
2615 BTRFS_CSUM_SIZE);
2616 btrfs_csum_final(crc, sb->csum);
2617
2618 /*
2619 * one reference for us, and we leave it for the
2620 * caller
2621 */
2622 bh = __getblk(device->bdev, bytenr / 4096,
2623 BTRFS_SUPER_INFO_SIZE);
2624 memcpy(bh->b_data, sb, BTRFS_SUPER_INFO_SIZE);
2625
2626 /* one reference for submit_bh */
2627 get_bh(bh);
2628
2629 set_buffer_uptodate(bh);
2630 lock_buffer(bh);
2631 bh->b_end_io = btrfs_end_buffer_write_sync;
2632 }
2633
2634 /*
2635 * we fua the first super. The others we allow
2636 * to go down lazy.
2637 */
2638 ret = submit_bh(WRITE_FUA, bh);
2639 if (ret)
2640 errors++;
2641 }
2642 return errors < i ? 0 : -1;
2643 }
2644
2645 /*
2646 * endio for the write_dev_flush, this will wake anyone waiting
2647 * for the barrier when it is done
2648 */
2649 static void btrfs_end_empty_barrier(struct bio *bio, int err)
2650 {
2651 if (err) {
2652 if (err == -EOPNOTSUPP)
2653 set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
2654 clear_bit(BIO_UPTODATE, &bio->bi_flags);
2655 }
2656 if (bio->bi_private)
2657 complete(bio->bi_private);
2658 bio_put(bio);
2659 }
2660
2661 /*
2662 * trigger flushes for one the devices. If you pass wait == 0, the flushes are
2663 * sent down. With wait == 1, it waits for the previous flush.
2664 *
2665 * any device where the flush fails with eopnotsupp are flagged as not-barrier
2666 * capable
2667 */
2668 static int write_dev_flush(struct btrfs_device *device, int wait)
2669 {
2670 struct bio *bio;
2671 int ret = 0;
2672
2673 if (device->nobarriers)
2674 return 0;
2675
2676 if (wait) {
2677 bio = device->flush_bio;
2678 if (!bio)
2679 return 0;
2680
2681 wait_for_completion(&device->flush_wait);
2682
2683 if (bio_flagged(bio, BIO_EOPNOTSUPP)) {
2684 printk("btrfs: disabling barriers on dev %s\n",
2685 device->name);
2686 device->nobarriers = 1;
2687 }
2688 if (!bio_flagged(bio, BIO_UPTODATE)) {
2689 ret = -EIO;
2690 }
2691
2692 /* drop the reference from the wait == 0 run */
2693 bio_put(bio);
2694 device->flush_bio = NULL;
2695
2696 return ret;
2697 }
2698
2699 /*
2700 * one reference for us, and we leave it for the
2701 * caller
2702 */
2703 device->flush_bio = NULL;;
2704 bio = bio_alloc(GFP_NOFS, 0);
2705 if (!bio)
2706 return -ENOMEM;
2707
2708 bio->bi_end_io = btrfs_end_empty_barrier;
2709 bio->bi_bdev = device->bdev;
2710 init_completion(&device->flush_wait);
2711 bio->bi_private = &device->flush_wait;
2712 device->flush_bio = bio;
2713
2714 bio_get(bio);
2715 submit_bio(WRITE_FLUSH, bio);
2716
2717 return 0;
2718 }
2719
2720 /*
2721 * send an empty flush down to each device in parallel,
2722 * then wait for them
2723 */
2724 static int barrier_all_devices(struct btrfs_fs_info *info)
2725 {
2726 struct list_head *head;
2727 struct btrfs_device *dev;
2728 int errors = 0;
2729 int ret;
2730
2731 /* send down all the barriers */
2732 head = &info->fs_devices->devices;
2733 list_for_each_entry_rcu(dev, head, dev_list) {
2734 if (dev->missing)
2735 continue;
2736 if (!dev->bdev) {
2737 errors++;
2738 continue;
2739 }
2740 if (!dev->in_fs_metadata || !dev->writeable)
2741 continue;
2742
2743 ret = write_dev_flush(dev, 0);
2744 if (ret)
2745 errors++;
2746 }
2747
2748 /* wait for all the barriers */
2749 list_for_each_entry_rcu(dev, head, dev_list) {
2750 if (dev->missing)
2751 continue;
2752 if (!dev->bdev) {
2753 errors++;
2754 continue;
2755 }
2756 if (!dev->in_fs_metadata || !dev->writeable)
2757 continue;
2758
2759 ret = write_dev_flush(dev, 1);
2760 if (ret)
2761 errors++;
2762 }
2763 if (errors)
2764 return -EIO;
2765 return 0;
2766 }
2767
2768 int write_all_supers(struct btrfs_root *root, int max_mirrors)
2769 {
2770 struct list_head *head;
2771 struct btrfs_device *dev;
2772 struct btrfs_super_block *sb;
2773 struct btrfs_dev_item *dev_item;
2774 int ret;
2775 int do_barriers;
2776 int max_errors;
2777 int total_errors = 0;
2778 u64 flags;
2779
2780 max_errors = btrfs_super_num_devices(root->fs_info->super_copy) - 1;
2781 do_barriers = !btrfs_test_opt(root, NOBARRIER);
2782 backup_super_roots(root->fs_info);
2783
2784 sb = root->fs_info->super_for_commit;
2785 dev_item = &sb->dev_item;
2786
2787 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2788 head = &root->fs_info->fs_devices->devices;
2789
2790 if (do_barriers)
2791 barrier_all_devices(root->fs_info);
2792
2793 list_for_each_entry_rcu(dev, head, dev_list) {
2794 if (!dev->bdev) {
2795 total_errors++;
2796 continue;
2797 }
2798 if (!dev->in_fs_metadata || !dev->writeable)
2799 continue;
2800
2801 btrfs_set_stack_device_generation(dev_item, 0);
2802 btrfs_set_stack_device_type(dev_item, dev->type);
2803 btrfs_set_stack_device_id(dev_item, dev->devid);
2804 btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes);
2805 btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used);
2806 btrfs_set_stack_device_io_align(dev_item, dev->io_align);
2807 btrfs_set_stack_device_io_width(dev_item, dev->io_width);
2808 btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
2809 memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
2810 memcpy(dev_item->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
2811
2812 flags = btrfs_super_flags(sb);
2813 btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
2814
2815 ret = write_dev_supers(dev, sb, do_barriers, 0, max_mirrors);
2816 if (ret)
2817 total_errors++;
2818 }
2819 if (total_errors > max_errors) {
2820 printk(KERN_ERR "btrfs: %d errors while writing supers\n",
2821 total_errors);
2822 BUG();
2823 }
2824
2825 total_errors = 0;
2826 list_for_each_entry_rcu(dev, head, dev_list) {
2827 if (!dev->bdev)
2828 continue;
2829 if (!dev->in_fs_metadata || !dev->writeable)
2830 continue;
2831
2832 ret = write_dev_supers(dev, sb, do_barriers, 1, max_mirrors);
2833 if (ret)
2834 total_errors++;
2835 }
2836 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2837 if (total_errors > max_errors) {
2838 printk(KERN_ERR "btrfs: %d errors while writing supers\n",
2839 total_errors);
2840 BUG();
2841 }
2842 return 0;
2843 }
2844
2845 int write_ctree_super(struct btrfs_trans_handle *trans,
2846 struct btrfs_root *root, int max_mirrors)
2847 {
2848 int ret;
2849
2850 ret = write_all_supers(root, max_mirrors);
2851 return ret;
2852 }
2853
2854 int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
2855 {
2856 spin_lock(&fs_info->fs_roots_radix_lock);
2857 radix_tree_delete(&fs_info->fs_roots_radix,
2858 (unsigned long)root->root_key.objectid);
2859 spin_unlock(&fs_info->fs_roots_radix_lock);
2860
2861 if (btrfs_root_refs(&root->root_item) == 0)
2862 synchronize_srcu(&fs_info->subvol_srcu);
2863
2864 __btrfs_remove_free_space_cache(root->free_ino_pinned);
2865 __btrfs_remove_free_space_cache(root->free_ino_ctl);
2866 free_fs_root(root);
2867 return 0;
2868 }
2869
2870 static void free_fs_root(struct btrfs_root *root)
2871 {
2872 iput(root->cache_inode);
2873 WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
2874 if (root->anon_dev)
2875 free_anon_bdev(root->anon_dev);
2876 free_extent_buffer(root->node);
2877 free_extent_buffer(root->commit_root);
2878 kfree(root->free_ino_ctl);
2879 kfree(root->free_ino_pinned);
2880 kfree(root->name);
2881 kfree(root);
2882 }
2883
2884 static int del_fs_roots(struct btrfs_fs_info *fs_info)
2885 {
2886 int ret;
2887 struct btrfs_root *gang[8];
2888 int i;
2889
2890 while (!list_empty(&fs_info->dead_roots)) {
2891 gang[0] = list_entry(fs_info->dead_roots.next,
2892 struct btrfs_root, root_list);
2893 list_del(&gang[0]->root_list);
2894
2895 if (gang[0]->in_radix) {
2896 btrfs_free_fs_root(fs_info, gang[0]);
2897 } else {
2898 free_extent_buffer(gang[0]->node);
2899 free_extent_buffer(gang[0]->commit_root);
2900 kfree(gang[0]);
2901 }
2902 }
2903
2904 while (1) {
2905 ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
2906 (void **)gang, 0,
2907 ARRAY_SIZE(gang));
2908 if (!ret)
2909 break;
2910 for (i = 0; i < ret; i++)
2911 btrfs_free_fs_root(fs_info, gang[i]);
2912 }
2913 return 0;
2914 }
2915
2916 int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
2917 {
2918 u64 root_objectid = 0;
2919 struct btrfs_root *gang[8];
2920 int i;
2921 int ret;
2922
2923 while (1) {
2924 ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
2925 (void **)gang, root_objectid,
2926 ARRAY_SIZE(gang));
2927 if (!ret)
2928 break;
2929
2930 root_objectid = gang[ret - 1]->root_key.objectid + 1;
2931 for (i = 0; i < ret; i++) {
2932 int err;
2933
2934 root_objectid = gang[i]->root_key.objectid;
2935 err = btrfs_orphan_cleanup(gang[i]);
2936 if (err)
2937 return err;
2938 }
2939 root_objectid++;
2940 }
2941 return 0;
2942 }
2943
2944 int btrfs_commit_super(struct btrfs_root *root)
2945 {
2946 struct btrfs_trans_handle *trans;
2947 int ret;
2948
2949 mutex_lock(&root->fs_info->cleaner_mutex);
2950 btrfs_run_delayed_iputs(root);
2951 btrfs_clean_old_snapshots(root);
2952 mutex_unlock(&root->fs_info->cleaner_mutex);
2953
2954 /* wait until ongoing cleanup work done */
2955 down_write(&root->fs_info->cleanup_work_sem);
2956 up_write(&root->fs_info->cleanup_work_sem);
2957
2958 trans = btrfs_join_transaction(root);
2959 if (IS_ERR(trans))
2960 return PTR_ERR(trans);
2961 ret = btrfs_commit_transaction(trans, root);
2962 BUG_ON(ret);
2963 /* run commit again to drop the original snapshot */
2964 trans = btrfs_join_transaction(root);
2965 if (IS_ERR(trans))
2966 return PTR_ERR(trans);
2967 btrfs_commit_transaction(trans, root);
2968 ret = btrfs_write_and_wait_transaction(NULL, root);
2969 BUG_ON(ret);
2970
2971 ret = write_ctree_super(NULL, root, 0);
2972 return ret;
2973 }
2974
2975 int close_ctree(struct btrfs_root *root)
2976 {
2977 struct btrfs_fs_info *fs_info = root->fs_info;
2978 int ret;
2979
2980 fs_info->closing = 1;
2981 smp_mb();
2982
2983 btrfs_scrub_cancel(root);
2984
2985 /* wait for any defraggers to finish */
2986 wait_event(fs_info->transaction_wait,
2987 (atomic_read(&fs_info->defrag_running) == 0));
2988
2989 /* clear out the rbtree of defraggable inodes */
2990 btrfs_run_defrag_inodes(root->fs_info);
2991
2992 /*
2993 * Here come 2 situations when btrfs is broken to flip readonly:
2994 *
2995 * 1. when btrfs flips readonly somewhere else before
2996 * btrfs_commit_super, sb->s_flags has MS_RDONLY flag,
2997 * and btrfs will skip to write sb directly to keep
2998 * ERROR state on disk.
2999 *
3000 * 2. when btrfs flips readonly just in btrfs_commit_super,
3001 * and in such case, btrfs cannot write sb via btrfs_commit_super,
3002 * and since fs_state has been set BTRFS_SUPER_FLAG_ERROR flag,
3003 * btrfs will cleanup all FS resources first and write sb then.
3004 */
3005 if (!(fs_info->sb->s_flags & MS_RDONLY)) {
3006 ret = btrfs_commit_super(root);
3007 if (ret)
3008 printk(KERN_ERR "btrfs: commit super ret %d\n", ret);
3009 }
3010
3011 if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) {
3012 ret = btrfs_error_commit_super(root);
3013 if (ret)
3014 printk(KERN_ERR "btrfs: commit super ret %d\n", ret);
3015 }
3016
3017 btrfs_put_block_group_cache(fs_info);
3018
3019 kthread_stop(root->fs_info->transaction_kthread);
3020 kthread_stop(root->fs_info->cleaner_kthread);
3021
3022 fs_info->closing = 2;
3023 smp_mb();
3024
3025 if (fs_info->delalloc_bytes) {
3026 printk(KERN_INFO "btrfs: at unmount delalloc count %llu\n",
3027 (unsigned long long)fs_info->delalloc_bytes);
3028 }
3029 if (fs_info->total_ref_cache_size) {
3030 printk(KERN_INFO "btrfs: at umount reference cache size %llu\n",
3031 (unsigned long long)fs_info->total_ref_cache_size);
3032 }
3033
3034 free_extent_buffer(fs_info->extent_root->node);
3035 free_extent_buffer(fs_info->extent_root->commit_root);
3036 free_extent_buffer(fs_info->tree_root->node);
3037 free_extent_buffer(fs_info->tree_root->commit_root);
3038 free_extent_buffer(root->fs_info->chunk_root->node);
3039 free_extent_buffer(root->fs_info->chunk_root->commit_root);
3040 free_extent_buffer(root->fs_info->dev_root->node);
3041 free_extent_buffer(root->fs_info->dev_root->commit_root);
3042 free_extent_buffer(root->fs_info->csum_root->node);
3043 free_extent_buffer(root->fs_info->csum_root->commit_root);
3044
3045 btrfs_free_block_groups(root->fs_info);
3046
3047 del_fs_roots(fs_info);
3048
3049 iput(fs_info->btree_inode);
3050
3051 btrfs_stop_workers(&fs_info->generic_worker);
3052 btrfs_stop_workers(&fs_info->fixup_workers);
3053 btrfs_stop_workers(&fs_info->delalloc_workers);
3054 btrfs_stop_workers(&fs_info->workers);
3055 btrfs_stop_workers(&fs_info->endio_workers);
3056 btrfs_stop_workers(&fs_info->endio_meta_workers);
3057 btrfs_stop_workers(&fs_info->endio_meta_write_workers);
3058 btrfs_stop_workers(&fs_info->endio_write_workers);
3059 btrfs_stop_workers(&fs_info->endio_freespace_worker);
3060 btrfs_stop_workers(&fs_info->submit_workers);
3061 btrfs_stop_workers(&fs_info->delayed_workers);
3062 btrfs_stop_workers(&fs_info->caching_workers);
3063 btrfs_stop_workers(&fs_info->readahead_workers);
3064
3065 btrfs_close_devices(fs_info->fs_devices);
3066 btrfs_mapping_tree_free(&fs_info->mapping_tree);
3067
3068 bdi_destroy(&fs_info->bdi);
3069 cleanup_srcu_struct(&fs_info->subvol_srcu);
3070
3071 free_fs_info(fs_info);
3072
3073 return 0;
3074 }
3075
3076 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid)
3077 {
3078 int ret;
3079 struct inode *btree_inode = buf->first_page->mapping->host;
3080
3081 ret = extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree, buf,
3082 NULL);
3083 if (!ret)
3084 return ret;
3085
3086 ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf,
3087 parent_transid);
3088 return !ret;
3089 }
3090
3091 int btrfs_set_buffer_uptodate(struct extent_buffer *buf)
3092 {
3093 struct inode *btree_inode = buf->first_page->mapping->host;
3094 return set_extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree,
3095 buf);
3096 }
3097
3098 void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
3099 {
3100 struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
3101 u64 transid = btrfs_header_generation(buf);
3102 struct inode *btree_inode = root->fs_info->btree_inode;
3103 int was_dirty;
3104
3105 btrfs_assert_tree_locked(buf);
3106 if (transid != root->fs_info->generation) {
3107 printk(KERN_CRIT "btrfs transid mismatch buffer %llu, "
3108 "found %llu running %llu\n",
3109 (unsigned long long)buf->start,
3110 (unsigned long long)transid,
3111 (unsigned long long)root->fs_info->generation);
3112 WARN_ON(1);
3113 }
3114 was_dirty = set_extent_buffer_dirty(&BTRFS_I(btree_inode)->io_tree,
3115 buf);
3116 if (!was_dirty) {
3117 spin_lock(&root->fs_info->delalloc_lock);
3118 root->fs_info->dirty_metadata_bytes += buf->len;
3119 spin_unlock(&root->fs_info->delalloc_lock);
3120 }
3121 }
3122
3123 void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
3124 {
3125 /*
3126 * looks as though older kernels can get into trouble with
3127 * this code, they end up stuck in balance_dirty_pages forever
3128 */
3129 u64 num_dirty;
3130 unsigned long thresh = 32 * 1024 * 1024;
3131
3132 if (current->flags & PF_MEMALLOC)
3133 return;
3134
3135 btrfs_balance_delayed_items(root);
3136
3137 num_dirty = root->fs_info->dirty_metadata_bytes;
3138
3139 if (num_dirty > thresh) {
3140 balance_dirty_pages_ratelimited_nr(
3141 root->fs_info->btree_inode->i_mapping, 1);
3142 }
3143 return;
3144 }
3145
3146 void __btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
3147 {
3148 /*
3149 * looks as though older kernels can get into trouble with
3150 * this code, they end up stuck in balance_dirty_pages forever
3151 */
3152 u64 num_dirty;
3153 unsigned long thresh = 32 * 1024 * 1024;
3154
3155 if (current->flags & PF_MEMALLOC)
3156 return;
3157
3158 num_dirty = root->fs_info->dirty_metadata_bytes;
3159
3160 if (num_dirty > thresh) {
3161 balance_dirty_pages_ratelimited_nr(
3162 root->fs_info->btree_inode->i_mapping, 1);
3163 }
3164 return;
3165 }
3166
3167 int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid)
3168 {
3169 struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
3170 int ret;
3171 ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
3172 if (ret == 0)
3173 set_bit(EXTENT_BUFFER_UPTODATE, &buf->bflags);
3174 return ret;
3175 }
3176
3177 static int btree_lock_page_hook(struct page *page, void *data,
3178 void (*flush_fn)(void *))
3179 {
3180 struct inode *inode = page->mapping->host;
3181 struct btrfs_root *root = BTRFS_I(inode)->root;
3182 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
3183 struct extent_buffer *eb;
3184 unsigned long len;
3185 u64 bytenr = page_offset(page);
3186
3187 if (page->private == EXTENT_PAGE_PRIVATE)
3188 goto out;
3189
3190 len = page->private >> 2;
3191 eb = find_extent_buffer(io_tree, bytenr, len);
3192 if (!eb)
3193 goto out;
3194
3195 if (!btrfs_try_tree_write_lock(eb)) {
3196 flush_fn(data);
3197 btrfs_tree_lock(eb);
3198 }
3199 btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
3200
3201 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) {
3202 spin_lock(&root->fs_info->delalloc_lock);
3203 if (root->fs_info->dirty_metadata_bytes >= eb->len)
3204 root->fs_info->dirty_metadata_bytes -= eb->len;
3205 else
3206 WARN_ON(1);
3207 spin_unlock(&root->fs_info->delalloc_lock);
3208 }
3209
3210 btrfs_tree_unlock(eb);
3211 free_extent_buffer(eb);
3212 out:
3213 if (!trylock_page(page)) {
3214 flush_fn(data);
3215 lock_page(page);
3216 }
3217 return 0;
3218 }
3219
3220 static void btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
3221 int read_only)
3222 {
3223 if (read_only)
3224 return;
3225
3226 if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)
3227 printk(KERN_WARNING "warning: mount fs with errors, "
3228 "running btrfsck is recommended\n");
3229 }
3230
3231 int btrfs_error_commit_super(struct btrfs_root *root)
3232 {
3233 int ret;
3234
3235 mutex_lock(&root->fs_info->cleaner_mutex);
3236 btrfs_run_delayed_iputs(root);
3237 mutex_unlock(&root->fs_info->cleaner_mutex);
3238
3239 down_write(&root->fs_info->cleanup_work_sem);
3240 up_write(&root->fs_info->cleanup_work_sem);
3241
3242 /* cleanup FS via transaction */
3243 btrfs_cleanup_transaction(root);
3244
3245 ret = write_ctree_super(NULL, root, 0);
3246
3247 return ret;
3248 }
3249
3250 static int btrfs_destroy_ordered_operations(struct btrfs_root *root)
3251 {
3252 struct btrfs_inode *btrfs_inode;
3253 struct list_head splice;
3254
3255 INIT_LIST_HEAD(&splice);
3256
3257 mutex_lock(&root->fs_info->ordered_operations_mutex);
3258 spin_lock(&root->fs_info->ordered_extent_lock);
3259
3260 list_splice_init(&root->fs_info->ordered_operations, &splice);
3261 while (!list_empty(&splice)) {
3262 btrfs_inode = list_entry(splice.next, struct btrfs_inode,
3263 ordered_operations);
3264
3265 list_del_init(&btrfs_inode->ordered_operations);
3266
3267 btrfs_invalidate_inodes(btrfs_inode->root);
3268 }
3269
3270 spin_unlock(&root->fs_info->ordered_extent_lock);
3271 mutex_unlock(&root->fs_info->ordered_operations_mutex);
3272
3273 return 0;
3274 }
3275
3276 static int btrfs_destroy_ordered_extents(struct btrfs_root *root)
3277 {
3278 struct list_head splice;
3279 struct btrfs_ordered_extent *ordered;
3280 struct inode *inode;
3281
3282 INIT_LIST_HEAD(&splice);
3283
3284 spin_lock(&root->fs_info->ordered_extent_lock);
3285
3286 list_splice_init(&root->fs_info->ordered_extents, &splice);
3287 while (!list_empty(&splice)) {
3288 ordered = list_entry(splice.next, struct btrfs_ordered_extent,
3289 root_extent_list);
3290
3291 list_del_init(&ordered->root_extent_list);
3292 atomic_inc(&ordered->refs);
3293
3294 /* the inode may be getting freed (in sys_unlink path). */
3295 inode = igrab(ordered->inode);
3296
3297 spin_unlock(&root->fs_info->ordered_extent_lock);
3298 if (inode)
3299 iput(inode);
3300
3301 atomic_set(&ordered->refs, 1);
3302 btrfs_put_ordered_extent(ordered);
3303
3304 spin_lock(&root->fs_info->ordered_extent_lock);
3305 }
3306
3307 spin_unlock(&root->fs_info->ordered_extent_lock);
3308
3309 return 0;
3310 }
3311
3312 static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
3313 struct btrfs_root *root)
3314 {
3315 struct rb_node *node;
3316 struct btrfs_delayed_ref_root *delayed_refs;
3317 struct btrfs_delayed_ref_node *ref;
3318 int ret = 0;
3319
3320 delayed_refs = &trans->delayed_refs;
3321
3322 spin_lock(&delayed_refs->lock);
3323 if (delayed_refs->num_entries == 0) {
3324 spin_unlock(&delayed_refs->lock);
3325 printk(KERN_INFO "delayed_refs has NO entry\n");
3326 return ret;
3327 }
3328
3329 node = rb_first(&delayed_refs->root);
3330 while (node) {
3331 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
3332 node = rb_next(node);
3333
3334 ref->in_tree = 0;
3335 rb_erase(&ref->rb_node, &delayed_refs->root);
3336 delayed_refs->num_entries--;
3337
3338 atomic_set(&ref->refs, 1);
3339 if (btrfs_delayed_ref_is_head(ref)) {
3340 struct btrfs_delayed_ref_head *head;
3341
3342 head = btrfs_delayed_node_to_head(ref);
3343 mutex_lock(&head->mutex);
3344 kfree(head->extent_op);
3345 delayed_refs->num_heads--;
3346 if (list_empty(&head->cluster))
3347 delayed_refs->num_heads_ready--;
3348 list_del_init(&head->cluster);
3349 mutex_unlock(&head->mutex);
3350 }
3351
3352 spin_unlock(&delayed_refs->lock);
3353 btrfs_put_delayed_ref(ref);
3354
3355 cond_resched();
3356 spin_lock(&delayed_refs->lock);
3357 }
3358
3359 spin_unlock(&delayed_refs->lock);
3360
3361 return ret;
3362 }
3363
3364 static int btrfs_destroy_pending_snapshots(struct btrfs_transaction *t)
3365 {
3366 struct btrfs_pending_snapshot *snapshot;
3367 struct list_head splice;
3368
3369 INIT_LIST_HEAD(&splice);
3370
3371 list_splice_init(&t->pending_snapshots, &splice);
3372
3373 while (!list_empty(&splice)) {
3374 snapshot = list_entry(splice.next,
3375 struct btrfs_pending_snapshot,
3376 list);
3377
3378 list_del_init(&snapshot->list);
3379
3380 kfree(snapshot);
3381 }
3382
3383 return 0;
3384 }
3385
3386 static int btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
3387 {
3388 struct btrfs_inode *btrfs_inode;
3389 struct list_head splice;
3390
3391 INIT_LIST_HEAD(&splice);
3392
3393 spin_lock(&root->fs_info->delalloc_lock);
3394 list_splice_init(&root->fs_info->delalloc_inodes, &splice);
3395
3396 while (!list_empty(&splice)) {
3397 btrfs_inode = list_entry(splice.next, struct btrfs_inode,
3398 delalloc_inodes);
3399
3400 list_del_init(&btrfs_inode->delalloc_inodes);
3401
3402 btrfs_invalidate_inodes(btrfs_inode->root);
3403 }
3404
3405 spin_unlock(&root->fs_info->delalloc_lock);
3406
3407 return 0;
3408 }
3409
3410 static int btrfs_destroy_marked_extents(struct btrfs_root *root,
3411 struct extent_io_tree *dirty_pages,
3412 int mark)
3413 {
3414 int ret;
3415 struct page *page;
3416 struct inode *btree_inode = root->fs_info->btree_inode;
3417 struct extent_buffer *eb;
3418 u64 start = 0;
3419 u64 end;
3420 u64 offset;
3421 unsigned long index;
3422
3423 while (1) {
3424 ret = find_first_extent_bit(dirty_pages, start, &start, &end,
3425 mark);
3426 if (ret)
3427 break;
3428
3429 clear_extent_bits(dirty_pages, start, end, mark, GFP_NOFS);
3430 while (start <= end) {
3431 index = start >> PAGE_CACHE_SHIFT;
3432 start = (u64)(index + 1) << PAGE_CACHE_SHIFT;
3433 page = find_get_page(btree_inode->i_mapping, index);
3434 if (!page)
3435 continue;
3436 offset = page_offset(page);
3437
3438 spin_lock(&dirty_pages->buffer_lock);
3439 eb = radix_tree_lookup(
3440 &(&BTRFS_I(page->mapping->host)->io_tree)->buffer,
3441 offset >> PAGE_CACHE_SHIFT);
3442 spin_unlock(&dirty_pages->buffer_lock);
3443 if (eb) {
3444 ret = test_and_clear_bit(EXTENT_BUFFER_DIRTY,
3445 &eb->bflags);
3446 atomic_set(&eb->refs, 1);
3447 }
3448 if (PageWriteback(page))
3449 end_page_writeback(page);
3450
3451 lock_page(page);
3452 if (PageDirty(page)) {
3453 clear_page_dirty_for_io(page);
3454 spin_lock_irq(&page->mapping->tree_lock);
3455 radix_tree_tag_clear(&page->mapping->page_tree,
3456 page_index(page),
3457 PAGECACHE_TAG_DIRTY);
3458 spin_unlock_irq(&page->mapping->tree_lock);
3459 }
3460
3461 page->mapping->a_ops->invalidatepage(page, 0);
3462 unlock_page(page);
3463 }
3464 }
3465
3466 return ret;
3467 }
3468
3469 static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
3470 struct extent_io_tree *pinned_extents)
3471 {
3472 struct extent_io_tree *unpin;
3473 u64 start;
3474 u64 end;
3475 int ret;
3476
3477 unpin = pinned_extents;
3478 while (1) {
3479 ret = find_first_extent_bit(unpin, 0, &start, &end,
3480 EXTENT_DIRTY);
3481 if (ret)
3482 break;
3483
3484 /* opt_discard */
3485 if (btrfs_test_opt(root, DISCARD))
3486 ret = btrfs_error_discard_extent(root, start,
3487 end + 1 - start,
3488 NULL);
3489
3490 clear_extent_dirty(unpin, start, end, GFP_NOFS);
3491 btrfs_error_unpin_extent_range(root, start, end);
3492 cond_resched();
3493 }
3494
3495 return 0;
3496 }
3497
3498 static int btrfs_cleanup_transaction(struct btrfs_root *root)
3499 {
3500 struct btrfs_transaction *t;
3501 LIST_HEAD(list);
3502
3503 WARN_ON(1);
3504
3505 mutex_lock(&root->fs_info->transaction_kthread_mutex);
3506
3507 spin_lock(&root->fs_info->trans_lock);
3508 list_splice_init(&root->fs_info->trans_list, &list);
3509 root->fs_info->trans_no_join = 1;
3510 spin_unlock(&root->fs_info->trans_lock);
3511
3512 while (!list_empty(&list)) {
3513 t = list_entry(list.next, struct btrfs_transaction, list);
3514 if (!t)
3515 break;
3516
3517 btrfs_destroy_ordered_operations(root);
3518
3519 btrfs_destroy_ordered_extents(root);
3520
3521 btrfs_destroy_delayed_refs(t, root);
3522
3523 btrfs_block_rsv_release(root,
3524 &root->fs_info->trans_block_rsv,
3525 t->dirty_pages.dirty_bytes);
3526
3527 /* FIXME: cleanup wait for commit */
3528 t->in_commit = 1;
3529 t->blocked = 1;
3530 if (waitqueue_active(&root->fs_info->transaction_blocked_wait))
3531 wake_up(&root->fs_info->transaction_blocked_wait);
3532
3533 t->blocked = 0;
3534 if (waitqueue_active(&root->fs_info->transaction_wait))
3535 wake_up(&root->fs_info->transaction_wait);
3536
3537 t->commit_done = 1;
3538 if (waitqueue_active(&t->commit_wait))
3539 wake_up(&t->commit_wait);
3540
3541 btrfs_destroy_pending_snapshots(t);
3542
3543 btrfs_destroy_delalloc_inodes(root);
3544
3545 spin_lock(&root->fs_info->trans_lock);
3546 root->fs_info->running_transaction = NULL;
3547 spin_unlock(&root->fs_info->trans_lock);
3548
3549 btrfs_destroy_marked_extents(root, &t->dirty_pages,
3550 EXTENT_DIRTY);
3551
3552 btrfs_destroy_pinned_extent(root,
3553 root->fs_info->pinned_extents);
3554
3555 atomic_set(&t->use_count, 0);
3556 list_del_init(&t->list);
3557 memset(t, 0, sizeof(*t));
3558 kmem_cache_free(btrfs_transaction_cachep, t);
3559 }
3560
3561 spin_lock(&root->fs_info->trans_lock);
3562 root->fs_info->trans_no_join = 0;
3563 spin_unlock(&root->fs_info->trans_lock);
3564 mutex_unlock(&root->fs_info->transaction_kthread_mutex);
3565
3566 return 0;
3567 }
3568
3569 static struct extent_io_ops btree_extent_io_ops = {
3570 .write_cache_pages_lock_hook = btree_lock_page_hook,
3571 .readpage_end_io_hook = btree_readpage_end_io_hook,
3572 .readpage_io_failed_hook = btree_io_failed_hook,
3573 .submit_bio_hook = btree_submit_bio_hook,
3574 /* note we're sharing with inode.c for the merge bio hook */
3575 .merge_bio_hook = btrfs_merge_bio_hook,
3576 };
Linux with added FPC-III support