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Btrfs: deal with errors from updating the tree log
[linux-2.6-block.git] / fs / btrfs / disk-io.c
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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 "compat.h"
32#include "ctree.h"
33#include "disk-io.h"
34#include "transaction.h"
35#include "btrfs_inode.h"
36#include "volumes.h"
37#include "print-tree.h"
38#include "async-thread.h"
39#include "locking.h"
40#include "tree-log.h"
41#include "free-space-cache.h"
42
43static struct extent_io_ops btree_extent_io_ops;
44static void end_workqueue_fn(struct btrfs_work *work);
45static void free_fs_root(struct btrfs_root *root);
46
47/*
48 * end_io_wq structs are used to do processing in task context when an IO is
49 * complete. This is used during reads to verify checksums, and it is used
50 * by writes to insert metadata for new file extents after IO is complete.
51 */
52struct end_io_wq {
53 struct bio *bio;
54 bio_end_io_t *end_io;
55 void *private;
56 struct btrfs_fs_info *info;
57 int error;
58 int metadata;
59 struct list_head list;
60 struct btrfs_work work;
61};
62
63/*
64 * async submit bios are used to offload expensive checksumming
65 * onto the worker threads. They checksum file and metadata bios
66 * just before they are sent down the IO stack.
67 */
68struct async_submit_bio {
69 struct inode *inode;
70 struct bio *bio;
71 struct list_head list;
72 extent_submit_bio_hook_t *submit_bio_start;
73 extent_submit_bio_hook_t *submit_bio_done;
74 int rw;
75 int mirror_num;
76 unsigned long bio_flags;
77 /*
78 * bio_offset is optional, can be used if the pages in the bio
79 * can't tell us where in the file the bio should go
80 */
81 u64 bio_offset;
82 struct btrfs_work work;
83};
84
85/* These are used to set the lockdep class on the extent buffer locks.
86 * The class is set by the readpage_end_io_hook after the buffer has
87 * passed csum validation but before the pages are unlocked.
88 *
89 * The lockdep class is also set by btrfs_init_new_buffer on freshly
90 * allocated blocks.
91 *
92 * The class is based on the level in the tree block, which allows lockdep
93 * to know that lower nodes nest inside the locks of higher nodes.
94 *
95 * We also add a check to make sure the highest level of the tree is
96 * the same as our lockdep setup here. If BTRFS_MAX_LEVEL changes, this
97 * code needs update as well.
98 */
99#ifdef CONFIG_DEBUG_LOCK_ALLOC
100# if BTRFS_MAX_LEVEL != 8
101# error
102# endif
103static struct lock_class_key btrfs_eb_class[BTRFS_MAX_LEVEL + 1];
104static const char *btrfs_eb_name[BTRFS_MAX_LEVEL + 1] = {
105 /* leaf */
106 "btrfs-extent-00",
107 "btrfs-extent-01",
108 "btrfs-extent-02",
109 "btrfs-extent-03",
110 "btrfs-extent-04",
111 "btrfs-extent-05",
112 "btrfs-extent-06",
113 "btrfs-extent-07",
114 /* highest possible level */
115 "btrfs-extent-08",
116};
117#endif
118
119/*
120 * extents on the btree inode are pretty simple, there's one extent
121 * that covers the entire device
122 */
123static struct extent_map *btree_get_extent(struct inode *inode,
124 struct page *page, size_t page_offset, u64 start, u64 len,
125 int create)
126{
127 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
128 struct extent_map *em;
129 int ret;
130
131 read_lock(&em_tree->lock);
132 em = lookup_extent_mapping(em_tree, start, len);
133 if (em) {
134 em->bdev =
135 BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
136 read_unlock(&em_tree->lock);
137 goto out;
138 }
139 read_unlock(&em_tree->lock);
140
141 em = alloc_extent_map(GFP_NOFS);
142 if (!em) {
143 em = ERR_PTR(-ENOMEM);
144 goto out;
145 }
146 em->start = 0;
147 em->len = (u64)-1;
148 em->block_len = (u64)-1;
149 em->block_start = 0;
150 em->bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
151
152 write_lock(&em_tree->lock);
153 ret = add_extent_mapping(em_tree, em);
154 if (ret == -EEXIST) {
155 u64 failed_start = em->start;
156 u64 failed_len = em->len;
157
158 free_extent_map(em);
159 em = lookup_extent_mapping(em_tree, start, len);
160 if (em) {
161 ret = 0;
162 } else {
163 em = lookup_extent_mapping(em_tree, failed_start,
164 failed_len);
165 ret = -EIO;
166 }
167 } else if (ret) {
168 free_extent_map(em);
169 em = NULL;
170 }
171 write_unlock(&em_tree->lock);
172
173 if (ret)
174 em = ERR_PTR(ret);
175out:
176 return em;
177}
178
179u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len)
180{
181 return crc32c(seed, data, len);
182}
183
184void btrfs_csum_final(u32 crc, char *result)
185{
186 *(__le32 *)result = ~cpu_to_le32(crc);
187}
188
189/*
190 * compute the csum for a btree block, and either verify it or write it
191 * into the csum field of the block.
192 */
193static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
194 int verify)
195{
196 u16 csum_size =
197 btrfs_super_csum_size(&root->fs_info->super_copy);
198 char *result = NULL;
199 unsigned long len;
200 unsigned long cur_len;
201 unsigned long offset = BTRFS_CSUM_SIZE;
202 char *map_token = NULL;
203 char *kaddr;
204 unsigned long map_start;
205 unsigned long map_len;
206 int err;
207 u32 crc = ~(u32)0;
208 unsigned long inline_result;
209
210 len = buf->len - offset;
211 while (len > 0) {
212 err = map_private_extent_buffer(buf, offset, 32,
213 &map_token, &kaddr,
214 &map_start, &map_len, KM_USER0);
215 if (err)
216 return 1;
217 cur_len = min(len, map_len - (offset - map_start));
218 crc = btrfs_csum_data(root, kaddr + offset - map_start,
219 crc, cur_len);
220 len -= cur_len;
221 offset += cur_len;
222 unmap_extent_buffer(buf, map_token, KM_USER0);
223 }
224 if (csum_size > sizeof(inline_result)) {
225 result = kzalloc(csum_size * sizeof(char), GFP_NOFS);
226 if (!result)
227 return 1;
228 } else {
229 result = (char *)&inline_result;
230 }
231
232 btrfs_csum_final(crc, result);
233
234 if (verify) {
235 if (memcmp_extent_buffer(buf, result, 0, csum_size)) {
236 u32 val;
237 u32 found = 0;
238 memcpy(&found, result, csum_size);
239
240 read_extent_buffer(buf, &val, 0, csum_size);
241 if (printk_ratelimit()) {
242 printk(KERN_INFO "btrfs: %s checksum verify "
243 "failed on %llu wanted %X found %X "
244 "level %d\n",
245 root->fs_info->sb->s_id,
246 (unsigned long long)buf->start, val, found,
247 btrfs_header_level(buf));
248 }
249 if (result != (char *)&inline_result)
250 kfree(result);
251 return 1;
252 }
253 } else {
254 write_extent_buffer(buf, result, 0, csum_size);
255 }
256 if (result != (char *)&inline_result)
257 kfree(result);
258 return 0;
259}
260
261/*
262 * we can't consider a given block up to date unless the transid of the
263 * block matches the transid in the parent node's pointer. This is how we
264 * detect blocks that either didn't get written at all or got written
265 * in the wrong place.
266 */
267static int verify_parent_transid(struct extent_io_tree *io_tree,
268 struct extent_buffer *eb, u64 parent_transid)
269{
270 struct extent_state *cached_state = NULL;
271 int ret;
272
273 if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
274 return 0;
275
276 lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1,
277 0, &cached_state, GFP_NOFS);
278 if (extent_buffer_uptodate(io_tree, eb, cached_state) &&
279 btrfs_header_generation(eb) == parent_transid) {
280 ret = 0;
281 goto out;
282 }
283 if (printk_ratelimit()) {
284 printk("parent transid verify failed on %llu wanted %llu "
285 "found %llu\n",
286 (unsigned long long)eb->start,
287 (unsigned long long)parent_transid,
288 (unsigned long long)btrfs_header_generation(eb));
289 }
290 ret = 1;
291 clear_extent_buffer_uptodate(io_tree, eb, &cached_state);
292out:
293 unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
294 &cached_state, GFP_NOFS);
295 return ret;
296}
297
298/*
299 * helper to read a given tree block, doing retries as required when
300 * the checksums don't match and we have alternate mirrors to try.
301 */
302static int btree_read_extent_buffer_pages(struct btrfs_root *root,
303 struct extent_buffer *eb,
304 u64 start, u64 parent_transid)
305{
306 struct extent_io_tree *io_tree;
307 int ret;
308 int num_copies = 0;
309 int mirror_num = 0;
310
311 io_tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree;
312 while (1) {
313 ret = read_extent_buffer_pages(io_tree, eb, start, 1,
314 btree_get_extent, mirror_num);
315 if (!ret &&
316 !verify_parent_transid(io_tree, eb, parent_transid))
317 return ret;
318
319 num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
320 eb->start, eb->len);
321 if (num_copies == 1)
322 return ret;
323
324 mirror_num++;
325 if (mirror_num > num_copies)
326 return ret;
327 }
328 return -EIO;
329}
330
331/*
332 * checksum a dirty tree block before IO. This has extra checks to make sure
333 * we only fill in the checksum field in the first page of a multi-page block
334 */
335
336static int csum_dirty_buffer(struct btrfs_root *root, struct page *page)
337{
338 struct extent_io_tree *tree;
339 u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
340 u64 found_start;
341 unsigned long len;
342 struct extent_buffer *eb;
343 int ret;
344
345 tree = &BTRFS_I(page->mapping->host)->io_tree;
346
347 if (page->private == EXTENT_PAGE_PRIVATE)
348 goto out;
349 if (!page->private)
350 goto out;
351 len = page->private >> 2;
352 WARN_ON(len == 0);
353
354 eb = alloc_extent_buffer(tree, start, len, page, GFP_NOFS);
355 ret = btree_read_extent_buffer_pages(root, eb, start + PAGE_CACHE_SIZE,
356 btrfs_header_generation(eb));
357 BUG_ON(ret);
358 found_start = btrfs_header_bytenr(eb);
359 if (found_start != start) {
360 WARN_ON(1);
361 goto err;
362 }
363 if (eb->first_page != page) {
364 WARN_ON(1);
365 goto err;
366 }
367 if (!PageUptodate(page)) {
368 WARN_ON(1);
369 goto err;
370 }
371 csum_tree_block(root, eb, 0);
372err:
373 free_extent_buffer(eb);
374out:
375 return 0;
376}
377
378static int check_tree_block_fsid(struct btrfs_root *root,
379 struct extent_buffer *eb)
380{
381 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
382 u8 fsid[BTRFS_UUID_SIZE];
383 int ret = 1;
384
385 read_extent_buffer(eb, fsid, (unsigned long)btrfs_header_fsid(eb),
386 BTRFS_FSID_SIZE);
387 while (fs_devices) {
388 if (!memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE)) {
389 ret = 0;
390 break;
391 }
392 fs_devices = fs_devices->seed;
393 }
394 return ret;
395}
396
397#ifdef CONFIG_DEBUG_LOCK_ALLOC
398void btrfs_set_buffer_lockdep_class(struct extent_buffer *eb, int level)
399{
400 lockdep_set_class_and_name(&eb->lock,
401 &btrfs_eb_class[level],
402 btrfs_eb_name[level]);
403}
404#endif
405
406static int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
407 struct extent_state *state)
408{
409 struct extent_io_tree *tree;
410 u64 found_start;
411 int found_level;
412 unsigned long len;
413 struct extent_buffer *eb;
414 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
415 int ret = 0;
416
417 tree = &BTRFS_I(page->mapping->host)->io_tree;
418 if (page->private == EXTENT_PAGE_PRIVATE)
419 goto out;
420 if (!page->private)
421 goto out;
422
423 len = page->private >> 2;
424 WARN_ON(len == 0);
425
426 eb = alloc_extent_buffer(tree, start, len, page, GFP_NOFS);
427
428 found_start = btrfs_header_bytenr(eb);
429 if (found_start != start) {
430 if (printk_ratelimit()) {
431 printk(KERN_INFO "btrfs bad tree block start "
432 "%llu %llu\n",
433 (unsigned long long)found_start,
434 (unsigned long long)eb->start);
435 }
436 ret = -EIO;
437 goto err;
438 }
439 if (eb->first_page != page) {
440 printk(KERN_INFO "btrfs bad first page %lu %lu\n",
441 eb->first_page->index, page->index);
442 WARN_ON(1);
443 ret = -EIO;
444 goto err;
445 }
446 if (check_tree_block_fsid(root, eb)) {
447 if (printk_ratelimit()) {
448 printk(KERN_INFO "btrfs bad fsid on block %llu\n",
449 (unsigned long long)eb->start);
450 }
451 ret = -EIO;
452 goto err;
453 }
454 found_level = btrfs_header_level(eb);
455
456 btrfs_set_buffer_lockdep_class(eb, found_level);
457
458 ret = csum_tree_block(root, eb, 1);
459 if (ret)
460 ret = -EIO;
461
462 end = min_t(u64, eb->len, PAGE_CACHE_SIZE);
463 end = eb->start + end - 1;
464err:
465 free_extent_buffer(eb);
466out:
467 return ret;
468}
469
470static void end_workqueue_bio(struct bio *bio, int err)
471{
472 struct end_io_wq *end_io_wq = bio->bi_private;
473 struct btrfs_fs_info *fs_info;
474
475 fs_info = end_io_wq->info;
476 end_io_wq->error = err;
477 end_io_wq->work.func = end_workqueue_fn;
478 end_io_wq->work.flags = 0;
479
480 if (bio->bi_rw & REQ_WRITE) {
481 if (end_io_wq->metadata == 1)
482 btrfs_queue_worker(&fs_info->endio_meta_write_workers,
483 &end_io_wq->work);
484 else if (end_io_wq->metadata == 2)
485 btrfs_queue_worker(&fs_info->endio_freespace_worker,
486 &end_io_wq->work);
487 else
488 btrfs_queue_worker(&fs_info->endio_write_workers,
489 &end_io_wq->work);
490 } else {
491 if (end_io_wq->metadata)
492 btrfs_queue_worker(&fs_info->endio_meta_workers,
493 &end_io_wq->work);
494 else
495 btrfs_queue_worker(&fs_info->endio_workers,
496 &end_io_wq->work);
497 }
498}
499
500/*
501 * For the metadata arg you want
502 *
503 * 0 - if data
504 * 1 - if normal metadta
505 * 2 - if writing to the free space cache area
506 */
507int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
508 int metadata)
509{
510 struct end_io_wq *end_io_wq;
511 end_io_wq = kmalloc(sizeof(*end_io_wq), GFP_NOFS);
512 if (!end_io_wq)
513 return -ENOMEM;
514
515 end_io_wq->private = bio->bi_private;
516 end_io_wq->end_io = bio->bi_end_io;
517 end_io_wq->info = info;
518 end_io_wq->error = 0;
519 end_io_wq->bio = bio;
520 end_io_wq->metadata = metadata;
521
522 bio->bi_private = end_io_wq;
523 bio->bi_end_io = end_workqueue_bio;
524 return 0;
525}
526
527unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info)
528{
529 unsigned long limit = min_t(unsigned long,
530 info->workers.max_workers,
531 info->fs_devices->open_devices);
532 return 256 * limit;
533}
534
535int btrfs_congested_async(struct btrfs_fs_info *info, int iodone)
536{
537 return atomic_read(&info->nr_async_bios) >
538 btrfs_async_submit_limit(info);
539}
540
541static void run_one_async_start(struct btrfs_work *work)
542{
543 struct async_submit_bio *async;
544
545 async = container_of(work, struct async_submit_bio, work);
546 async->submit_bio_start(async->inode, async->rw, async->bio,
547 async->mirror_num, async->bio_flags,
548 async->bio_offset);
549}
550
551static void run_one_async_done(struct btrfs_work *work)
552{
553 struct btrfs_fs_info *fs_info;
554 struct async_submit_bio *async;
555 int limit;
556
557 async = container_of(work, struct async_submit_bio, work);
558 fs_info = BTRFS_I(async->inode)->root->fs_info;
559
560 limit = btrfs_async_submit_limit(fs_info);
561 limit = limit * 2 / 3;
562
563 atomic_dec(&fs_info->nr_async_submits);
564
565 if (atomic_read(&fs_info->nr_async_submits) < limit &&
566 waitqueue_active(&fs_info->async_submit_wait))
567 wake_up(&fs_info->async_submit_wait);
568
569 async->submit_bio_done(async->inode, async->rw, async->bio,
570 async->mirror_num, async->bio_flags,
571 async->bio_offset);
572}
573
574static void run_one_async_free(struct btrfs_work *work)
575{
576 struct async_submit_bio *async;
577
578 async = container_of(work, struct async_submit_bio, work);
579 kfree(async);
580}
581
582int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode,
583 int rw, struct bio *bio, int mirror_num,
584 unsigned long bio_flags,
585 u64 bio_offset,
586 extent_submit_bio_hook_t *submit_bio_start,
587 extent_submit_bio_hook_t *submit_bio_done)
588{
589 struct async_submit_bio *async;
590
591 async = kmalloc(sizeof(*async), GFP_NOFS);
592 if (!async)
593 return -ENOMEM;
594
595 async->inode = inode;
596 async->rw = rw;
597 async->bio = bio;
598 async->mirror_num = mirror_num;
599 async->submit_bio_start = submit_bio_start;
600 async->submit_bio_done = submit_bio_done;
601
602 async->work.func = run_one_async_start;
603 async->work.ordered_func = run_one_async_done;
604 async->work.ordered_free = run_one_async_free;
605
606 async->work.flags = 0;
607 async->bio_flags = bio_flags;
608 async->bio_offset = bio_offset;
609
610 atomic_inc(&fs_info->nr_async_submits);
611
612 if (rw & REQ_SYNC)
613 btrfs_set_work_high_prio(&async->work);
614
615 btrfs_queue_worker(&fs_info->workers, &async->work);
616
617 while (atomic_read(&fs_info->async_submit_draining) &&
618 atomic_read(&fs_info->nr_async_submits)) {
619 wait_event(fs_info->async_submit_wait,
620 (atomic_read(&fs_info->nr_async_submits) == 0));
621 }
622
623 return 0;
624}
625
626static int btree_csum_one_bio(struct bio *bio)
627{
628 struct bio_vec *bvec = bio->bi_io_vec;
629 int bio_index = 0;
630 struct btrfs_root *root;
631
632 WARN_ON(bio->bi_vcnt <= 0);
633 while (bio_index < bio->bi_vcnt) {
634 root = BTRFS_I(bvec->bv_page->mapping->host)->root;
635 csum_dirty_buffer(root, bvec->bv_page);
636 bio_index++;
637 bvec++;
638 }
639 return 0;
640}
641
642static int __btree_submit_bio_start(struct inode *inode, int rw,
643 struct bio *bio, int mirror_num,
644 unsigned long bio_flags,
645 u64 bio_offset)
646{
647 /*
648 * when we're called for a write, we're already in the async
649 * submission context. Just jump into btrfs_map_bio
650 */
651 btree_csum_one_bio(bio);
652 return 0;
653}
654
655static int __btree_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
656 int mirror_num, unsigned long bio_flags,
657 u64 bio_offset)
658{
659 /*
660 * when we're called for a write, we're already in the async
661 * submission context. Just jump into btrfs_map_bio
662 */
663 return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio, mirror_num, 1);
664}
665
666static int btree_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
667 int mirror_num, unsigned long bio_flags,
668 u64 bio_offset)
669{
670 int ret;
671
672 ret = btrfs_bio_wq_end_io(BTRFS_I(inode)->root->fs_info,
673 bio, 1);
674 BUG_ON(ret);
675
676 if (!(rw & REQ_WRITE)) {
677 /*
678 * called for a read, do the setup so that checksum validation
679 * can happen in the async kernel threads
680 */
681 return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio,
682 mirror_num, 0);
683 }
684
685 /*
686 * kthread helpers are used to submit writes so that checksumming
687 * can happen in parallel across all CPUs
688 */
689 return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
690 inode, rw, bio, mirror_num, 0,
691 bio_offset,
692 __btree_submit_bio_start,
693 __btree_submit_bio_done);
694}
695
696static int btree_writepage(struct page *page, struct writeback_control *wbc)
697{
698 struct extent_io_tree *tree;
699 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
700 struct extent_buffer *eb;
701 int was_dirty;
702
703 tree = &BTRFS_I(page->mapping->host)->io_tree;
704 if (!(current->flags & PF_MEMALLOC)) {
705 return extent_write_full_page(tree, page,
706 btree_get_extent, wbc);
707 }
708
709 redirty_page_for_writepage(wbc, page);
710 eb = btrfs_find_tree_block(root, page_offset(page),
711 PAGE_CACHE_SIZE);
712 WARN_ON(!eb);
713
714 was_dirty = test_and_set_bit(EXTENT_BUFFER_DIRTY, &eb->bflags);
715 if (!was_dirty) {
716 spin_lock(&root->fs_info->delalloc_lock);
717 root->fs_info->dirty_metadata_bytes += PAGE_CACHE_SIZE;
718 spin_unlock(&root->fs_info->delalloc_lock);
719 }
720 free_extent_buffer(eb);
721
722 unlock_page(page);
723 return 0;
724}
725
726static int btree_writepages(struct address_space *mapping,
727 struct writeback_control *wbc)
728{
729 struct extent_io_tree *tree;
730 tree = &BTRFS_I(mapping->host)->io_tree;
731 if (wbc->sync_mode == WB_SYNC_NONE) {
732 struct btrfs_root *root = BTRFS_I(mapping->host)->root;
733 u64 num_dirty;
734 unsigned long thresh = 32 * 1024 * 1024;
735
736 if (wbc->for_kupdate)
737 return 0;
738
739 /* this is a bit racy, but that's ok */
740 num_dirty = root->fs_info->dirty_metadata_bytes;
741 if (num_dirty < thresh)
742 return 0;
743 }
744 return extent_writepages(tree, mapping, btree_get_extent, wbc);
745}
746
747static int btree_readpage(struct file *file, struct page *page)
748{
749 struct extent_io_tree *tree;
750 tree = &BTRFS_I(page->mapping->host)->io_tree;
751 return extent_read_full_page(tree, page, btree_get_extent);
752}
753
754static int btree_releasepage(struct page *page, gfp_t gfp_flags)
755{
756 struct extent_io_tree *tree;
757 struct extent_map_tree *map;
758 int ret;
759
760 if (PageWriteback(page) || PageDirty(page))
761 return 0;
762
763 tree = &BTRFS_I(page->mapping->host)->io_tree;
764 map = &BTRFS_I(page->mapping->host)->extent_tree;
765
766 ret = try_release_extent_state(map, tree, page, gfp_flags);
767 if (!ret)
768 return 0;
769
770 ret = try_release_extent_buffer(tree, page);
771 if (ret == 1) {
772 ClearPagePrivate(page);
773 set_page_private(page, 0);
774 page_cache_release(page);
775 }
776
777 return ret;
778}
779
780static void btree_invalidatepage(struct page *page, unsigned long offset)
781{
782 struct extent_io_tree *tree;
783 tree = &BTRFS_I(page->mapping->host)->io_tree;
784 extent_invalidatepage(tree, page, offset);
785 btree_releasepage(page, GFP_NOFS);
786 if (PagePrivate(page)) {
787 printk(KERN_WARNING "btrfs warning page private not zero "
788 "on page %llu\n", (unsigned long long)page_offset(page));
789 ClearPagePrivate(page);
790 set_page_private(page, 0);
791 page_cache_release(page);
792 }
793}
794
795static const struct address_space_operations btree_aops = {
796 .readpage = btree_readpage,
797 .writepage = btree_writepage,
798 .writepages = btree_writepages,
799 .releasepage = btree_releasepage,
800 .invalidatepage = btree_invalidatepage,
801 .sync_page = block_sync_page,
802};
803
804int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
805 u64 parent_transid)
806{
807 struct extent_buffer *buf = NULL;
808 struct inode *btree_inode = root->fs_info->btree_inode;
809 int ret = 0;
810
811 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
812 if (!buf)
813 return 0;
814 read_extent_buffer_pages(&BTRFS_I(btree_inode)->io_tree,
815 buf, 0, 0, btree_get_extent, 0);
816 free_extent_buffer(buf);
817 return ret;
818}
819
820struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
821 u64 bytenr, u32 blocksize)
822{
823 struct inode *btree_inode = root->fs_info->btree_inode;
824 struct extent_buffer *eb;
825 eb = find_extent_buffer(&BTRFS_I(btree_inode)->io_tree,
826 bytenr, blocksize, GFP_NOFS);
827 return eb;
828}
829
830struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
831 u64 bytenr, u32 blocksize)
832{
833 struct inode *btree_inode = root->fs_info->btree_inode;
834 struct extent_buffer *eb;
835
836 eb = alloc_extent_buffer(&BTRFS_I(btree_inode)->io_tree,
837 bytenr, blocksize, NULL, GFP_NOFS);
838 return eb;
839}
840
841
842int btrfs_write_tree_block(struct extent_buffer *buf)
843{
844 return filemap_fdatawrite_range(buf->first_page->mapping, buf->start,
845 buf->start + buf->len - 1);
846}
847
848int btrfs_wait_tree_block_writeback(struct extent_buffer *buf)
849{
850 return filemap_fdatawait_range(buf->first_page->mapping,
851 buf->start, buf->start + buf->len - 1);
852}
853
854struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
855 u32 blocksize, u64 parent_transid)
856{
857 struct extent_buffer *buf = NULL;
858 int ret;
859
860 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
861 if (!buf)
862 return NULL;
863
864 ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
865
866 if (ret == 0)
867 set_bit(EXTENT_BUFFER_UPTODATE, &buf->bflags);
868 return buf;
869
870}
871
872int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
873 struct extent_buffer *buf)
874{
875 struct inode *btree_inode = root->fs_info->btree_inode;
876 if (btrfs_header_generation(buf) ==
877 root->fs_info->running_transaction->transid) {
878 btrfs_assert_tree_locked(buf);
879
880 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) {
881 spin_lock(&root->fs_info->delalloc_lock);
882 if (root->fs_info->dirty_metadata_bytes >= buf->len)
883 root->fs_info->dirty_metadata_bytes -= buf->len;
884 else
885 WARN_ON(1);
886 spin_unlock(&root->fs_info->delalloc_lock);
887 }
888
889 /* ugh, clear_extent_buffer_dirty needs to lock the page */
890 btrfs_set_lock_blocking(buf);
891 clear_extent_buffer_dirty(&BTRFS_I(btree_inode)->io_tree,
892 buf);
893 }
894 return 0;
895}
896
897static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
898 u32 stripesize, struct btrfs_root *root,
899 struct btrfs_fs_info *fs_info,
900 u64 objectid)
901{
902 root->node = NULL;
903 root->commit_root = NULL;
904 root->sectorsize = sectorsize;
905 root->nodesize = nodesize;
906 root->leafsize = leafsize;
907 root->stripesize = stripesize;
908 root->ref_cows = 0;
909 root->track_dirty = 0;
910 root->in_radix = 0;
911 root->orphan_item_inserted = 0;
912 root->orphan_cleanup_state = 0;
913
914 root->fs_info = fs_info;
915 root->objectid = objectid;
916 root->last_trans = 0;
917 root->highest_objectid = 0;
918 root->name = NULL;
919 root->in_sysfs = 0;
920 root->inode_tree = RB_ROOT;
921 root->block_rsv = NULL;
922 root->orphan_block_rsv = NULL;
923
924 INIT_LIST_HEAD(&root->dirty_list);
925 INIT_LIST_HEAD(&root->orphan_list);
926 INIT_LIST_HEAD(&root->root_list);
927 spin_lock_init(&root->node_lock);
928 spin_lock_init(&root->orphan_lock);
929 spin_lock_init(&root->inode_lock);
930 spin_lock_init(&root->accounting_lock);
931 mutex_init(&root->objectid_mutex);
932 mutex_init(&root->log_mutex);
933 init_waitqueue_head(&root->log_writer_wait);
934 init_waitqueue_head(&root->log_commit_wait[0]);
935 init_waitqueue_head(&root->log_commit_wait[1]);
936 atomic_set(&root->log_commit[0], 0);
937 atomic_set(&root->log_commit[1], 0);
938 atomic_set(&root->log_writers, 0);
939 root->log_batch = 0;
940 root->log_transid = 0;
941 root->last_log_commit = 0;
942 extent_io_tree_init(&root->dirty_log_pages,
943 fs_info->btree_inode->i_mapping, GFP_NOFS);
944
945 memset(&root->root_key, 0, sizeof(root->root_key));
946 memset(&root->root_item, 0, sizeof(root->root_item));
947 memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
948 memset(&root->root_kobj, 0, sizeof(root->root_kobj));
949 root->defrag_trans_start = fs_info->generation;
950 init_completion(&root->kobj_unregister);
951 root->defrag_running = 0;
952 root->root_key.objectid = objectid;
953 root->anon_super.s_root = NULL;
954 root->anon_super.s_dev = 0;
955 INIT_LIST_HEAD(&root->anon_super.s_list);
956 INIT_LIST_HEAD(&root->anon_super.s_instances);
957 init_rwsem(&root->anon_super.s_umount);
958
959 return 0;
960}
961
962static int find_and_setup_root(struct btrfs_root *tree_root,
963 struct btrfs_fs_info *fs_info,
964 u64 objectid,
965 struct btrfs_root *root)
966{
967 int ret;
968 u32 blocksize;
969 u64 generation;
970
971 __setup_root(tree_root->nodesize, tree_root->leafsize,
972 tree_root->sectorsize, tree_root->stripesize,
973 root, fs_info, objectid);
974 ret = btrfs_find_last_root(tree_root, objectid,
975 &root->root_item, &root->root_key);
976 if (ret > 0)
977 return -ENOENT;
978 BUG_ON(ret);
979
980 generation = btrfs_root_generation(&root->root_item);
981 blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
982 root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
983 blocksize, generation);
984 BUG_ON(!root->node);
985 root->commit_root = btrfs_root_node(root);
986 return 0;
987}
988
989static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
990 struct btrfs_fs_info *fs_info)
991{
992 struct btrfs_root *root;
993 struct btrfs_root *tree_root = fs_info->tree_root;
994 struct extent_buffer *leaf;
995
996 root = kzalloc(sizeof(*root), GFP_NOFS);
997 if (!root)
998 return ERR_PTR(-ENOMEM);
999
1000 __setup_root(tree_root->nodesize, tree_root->leafsize,
1001 tree_root->sectorsize, tree_root->stripesize,
1002 root, fs_info, BTRFS_TREE_LOG_OBJECTID);
1003
1004 root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
1005 root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1006 root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
1007 /*
1008 * log trees do not get reference counted because they go away
1009 * before a real commit is actually done. They do store pointers
1010 * to file data extents, and those reference counts still get
1011 * updated (along with back refs to the log tree).
1012 */
1013 root->ref_cows = 0;
1014
1015 leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 0,
1016 BTRFS_TREE_LOG_OBJECTID, NULL, 0, 0, 0);
1017 if (IS_ERR(leaf)) {
1018 kfree(root);
1019 return ERR_CAST(leaf);
1020 }
1021
1022 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
1023 btrfs_set_header_bytenr(leaf, leaf->start);
1024 btrfs_set_header_generation(leaf, trans->transid);
1025 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
1026 btrfs_set_header_owner(leaf, BTRFS_TREE_LOG_OBJECTID);
1027 root->node = leaf;
1028
1029 write_extent_buffer(root->node, root->fs_info->fsid,
1030 (unsigned long)btrfs_header_fsid(root->node),
1031 BTRFS_FSID_SIZE);
1032 btrfs_mark_buffer_dirty(root->node);
1033 btrfs_tree_unlock(root->node);
1034 return root;
1035}
1036
1037int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
1038 struct btrfs_fs_info *fs_info)
1039{
1040 struct btrfs_root *log_root;
1041
1042 log_root = alloc_log_tree(trans, fs_info);
1043 if (IS_ERR(log_root))
1044 return PTR_ERR(log_root);
1045 WARN_ON(fs_info->log_root_tree);
1046 fs_info->log_root_tree = log_root;
1047 return 0;
1048}
1049
1050int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
1051 struct btrfs_root *root)
1052{
1053 struct btrfs_root *log_root;
1054 struct btrfs_inode_item *inode_item;
1055
1056 log_root = alloc_log_tree(trans, root->fs_info);
1057 if (IS_ERR(log_root))
1058 return PTR_ERR(log_root);
1059
1060 log_root->last_trans = trans->transid;
1061 log_root->root_key.offset = root->root_key.objectid;
1062
1063 inode_item = &log_root->root_item.inode;
1064 inode_item->generation = cpu_to_le64(1);
1065 inode_item->size = cpu_to_le64(3);
1066 inode_item->nlink = cpu_to_le32(1);
1067 inode_item->nbytes = cpu_to_le64(root->leafsize);
1068 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
1069
1070 btrfs_set_root_node(&log_root->root_item, log_root->node);
1071
1072 WARN_ON(root->log_root);
1073 root->log_root = log_root;
1074 root->log_transid = 0;
1075 root->last_log_commit = 0;
1076 return 0;
1077}
1078
1079struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
1080 struct btrfs_key *location)
1081{
1082 struct btrfs_root *root;
1083 struct btrfs_fs_info *fs_info = tree_root->fs_info;
1084 struct btrfs_path *path;
1085 struct extent_buffer *l;
1086 u64 generation;
1087 u32 blocksize;
1088 int ret = 0;
1089
1090 root = kzalloc(sizeof(*root), GFP_NOFS);
1091 if (!root)
1092 return ERR_PTR(-ENOMEM);
1093 if (location->offset == (u64)-1) {
1094 ret = find_and_setup_root(tree_root, fs_info,
1095 location->objectid, root);
1096 if (ret) {
1097 kfree(root);
1098 return ERR_PTR(ret);
1099 }
1100 goto out;
1101 }
1102
1103 __setup_root(tree_root->nodesize, tree_root->leafsize,
1104 tree_root->sectorsize, tree_root->stripesize,
1105 root, fs_info, location->objectid);
1106
1107 path = btrfs_alloc_path();
1108 BUG_ON(!path);
1109 ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
1110 if (ret == 0) {
1111 l = path->nodes[0];
1112 read_extent_buffer(l, &root->root_item,
1113 btrfs_item_ptr_offset(l, path->slots[0]),
1114 sizeof(root->root_item));
1115 memcpy(&root->root_key, location, sizeof(*location));
1116 }
1117 btrfs_free_path(path);
1118 if (ret) {
1119 if (ret > 0)
1120 ret = -ENOENT;
1121 return ERR_PTR(ret);
1122 }
1123
1124 generation = btrfs_root_generation(&root->root_item);
1125 blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
1126 root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
1127 blocksize, generation);
1128 root->commit_root = btrfs_root_node(root);
1129 BUG_ON(!root->node);
1130out:
1131 if (location->objectid != BTRFS_TREE_LOG_OBJECTID)
1132 root->ref_cows = 1;
1133
1134 return root;
1135}
1136
1137struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info,
1138 u64 root_objectid)
1139{
1140 struct btrfs_root *root;
1141
1142 if (root_objectid == BTRFS_ROOT_TREE_OBJECTID)
1143 return fs_info->tree_root;
1144 if (root_objectid == BTRFS_EXTENT_TREE_OBJECTID)
1145 return fs_info->extent_root;
1146
1147 root = radix_tree_lookup(&fs_info->fs_roots_radix,
1148 (unsigned long)root_objectid);
1149 return root;
1150}
1151
1152struct btrfs_root *btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
1153 struct btrfs_key *location)
1154{
1155 struct btrfs_root *root;
1156 int ret;
1157
1158 if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
1159 return fs_info->tree_root;
1160 if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
1161 return fs_info->extent_root;
1162 if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
1163 return fs_info->chunk_root;
1164 if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
1165 return fs_info->dev_root;
1166 if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
1167 return fs_info->csum_root;
1168again:
1169 spin_lock(&fs_info->fs_roots_radix_lock);
1170 root = radix_tree_lookup(&fs_info->fs_roots_radix,
1171 (unsigned long)location->objectid);
1172 spin_unlock(&fs_info->fs_roots_radix_lock);
1173 if (root)
1174 return root;
1175
1176 root = btrfs_read_fs_root_no_radix(fs_info->tree_root, location);
1177 if (IS_ERR(root))
1178 return root;
1179
1180 set_anon_super(&root->anon_super, NULL);
1181
1182 if (btrfs_root_refs(&root->root_item) == 0) {
1183 ret = -ENOENT;
1184 goto fail;
1185 }
1186
1187 ret = btrfs_find_orphan_item(fs_info->tree_root, location->objectid);
1188 if (ret < 0)
1189 goto fail;
1190 if (ret == 0)
1191 root->orphan_item_inserted = 1;
1192
1193 ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
1194 if (ret)
1195 goto fail;
1196
1197 spin_lock(&fs_info->fs_roots_radix_lock);
1198 ret = radix_tree_insert(&fs_info->fs_roots_radix,
1199 (unsigned long)root->root_key.objectid,
1200 root);
1201 if (ret == 0)
1202 root->in_radix = 1;
1203
1204 spin_unlock(&fs_info->fs_roots_radix_lock);
1205 radix_tree_preload_end();
1206 if (ret) {
1207 if (ret == -EEXIST) {
1208 free_fs_root(root);
1209 goto again;
1210 }
1211 goto fail;
1212 }
1213
1214 ret = btrfs_find_dead_roots(fs_info->tree_root,
1215 root->root_key.objectid);
1216 WARN_ON(ret);
1217 return root;
1218fail:
1219 free_fs_root(root);
1220 return ERR_PTR(ret);
1221}
1222
1223struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
1224 struct btrfs_key *location,
1225 const char *name, int namelen)
1226{
1227 return btrfs_read_fs_root_no_name(fs_info, location);
1228#if 0
1229 struct btrfs_root *root;
1230 int ret;
1231
1232 root = btrfs_read_fs_root_no_name(fs_info, location);
1233 if (!root)
1234 return NULL;
1235
1236 if (root->in_sysfs)
1237 return root;
1238
1239 ret = btrfs_set_root_name(root, name, namelen);
1240 if (ret) {
1241 free_extent_buffer(root->node);
1242 kfree(root);
1243 return ERR_PTR(ret);
1244 }
1245
1246 ret = btrfs_sysfs_add_root(root);
1247 if (ret) {
1248 free_extent_buffer(root->node);
1249 kfree(root->name);
1250 kfree(root);
1251 return ERR_PTR(ret);
1252 }
1253 root->in_sysfs = 1;
1254 return root;
1255#endif
1256}
1257
1258static int btrfs_congested_fn(void *congested_data, int bdi_bits)
1259{
1260 struct btrfs_fs_info *info = (struct btrfs_fs_info *)congested_data;
1261 int ret = 0;
1262 struct btrfs_device *device;
1263 struct backing_dev_info *bdi;
1264
1265 list_for_each_entry(device, &info->fs_devices->devices, dev_list) {
1266 if (!device->bdev)
1267 continue;
1268 bdi = blk_get_backing_dev_info(device->bdev);
1269 if (bdi && bdi_congested(bdi, bdi_bits)) {
1270 ret = 1;
1271 break;
1272 }
1273 }
1274 return ret;
1275}
1276
1277/*
1278 * this unplugs every device on the box, and it is only used when page
1279 * is null
1280 */
1281static void __unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
1282{
1283 struct btrfs_device *device;
1284 struct btrfs_fs_info *info;
1285
1286 info = (struct btrfs_fs_info *)bdi->unplug_io_data;
1287 list_for_each_entry(device, &info->fs_devices->devices, dev_list) {
1288 if (!device->bdev)
1289 continue;
1290
1291 bdi = blk_get_backing_dev_info(device->bdev);
1292 if (bdi->unplug_io_fn)
1293 bdi->unplug_io_fn(bdi, page);
1294 }
1295}
1296
1297static void btrfs_unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
1298{
1299 struct inode *inode;
1300 struct extent_map_tree *em_tree;
1301 struct extent_map *em;
1302 struct address_space *mapping;
1303 u64 offset;
1304
1305 /* the generic O_DIRECT read code does this */
1306 if (1 || !page) {
1307 __unplug_io_fn(bdi, page);
1308 return;
1309 }
1310
1311 /*
1312 * page->mapping may change at any time. Get a consistent copy
1313 * and use that for everything below
1314 */
1315 smp_mb();
1316 mapping = page->mapping;
1317 if (!mapping)
1318 return;
1319
1320 inode = mapping->host;
1321
1322 /*
1323 * don't do the expensive searching for a small number of
1324 * devices
1325 */
1326 if (BTRFS_I(inode)->root->fs_info->fs_devices->open_devices <= 2) {
1327 __unplug_io_fn(bdi, page);
1328 return;
1329 }
1330
1331 offset = page_offset(page);
1332
1333 em_tree = &BTRFS_I(inode)->extent_tree;
1334 read_lock(&em_tree->lock);
1335 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
1336 read_unlock(&em_tree->lock);
1337 if (!em) {
1338 __unplug_io_fn(bdi, page);
1339 return;
1340 }
1341
1342 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1343 free_extent_map(em);
1344 __unplug_io_fn(bdi, page);
1345 return;
1346 }
1347 offset = offset - em->start;
1348 btrfs_unplug_page(&BTRFS_I(inode)->root->fs_info->mapping_tree,
1349 em->block_start + offset, page);
1350 free_extent_map(em);
1351}
1352
1353/*
1354 * If this fails, caller must call bdi_destroy() to get rid of the
1355 * bdi again.
1356 */
1357static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi)
1358{
1359 int err;
1360
1361 bdi->capabilities = BDI_CAP_MAP_COPY;
1362 err = bdi_setup_and_register(bdi, "btrfs", BDI_CAP_MAP_COPY);
1363 if (err)
1364 return err;
1365
1366 bdi->ra_pages = default_backing_dev_info.ra_pages;
1367 bdi->unplug_io_fn = btrfs_unplug_io_fn;
1368 bdi->unplug_io_data = info;
1369 bdi->congested_fn = btrfs_congested_fn;
1370 bdi->congested_data = info;
1371 return 0;
1372}
1373
1374static int bio_ready_for_csum(struct bio *bio)
1375{
1376 u64 length = 0;
1377 u64 buf_len = 0;
1378 u64 start = 0;
1379 struct page *page;
1380 struct extent_io_tree *io_tree = NULL;
1381 struct bio_vec *bvec;
1382 int i;
1383 int ret;
1384
1385 bio_for_each_segment(bvec, bio, i) {
1386 page = bvec->bv_page;
1387 if (page->private == EXTENT_PAGE_PRIVATE) {
1388 length += bvec->bv_len;
1389 continue;
1390 }
1391 if (!page->private) {
1392 length += bvec->bv_len;
1393 continue;
1394 }
1395 length = bvec->bv_len;
1396 buf_len = page->private >> 2;
1397 start = page_offset(page) + bvec->bv_offset;
1398 io_tree = &BTRFS_I(page->mapping->host)->io_tree;
1399 }
1400 /* are we fully contained in this bio? */
1401 if (buf_len <= length)
1402 return 1;
1403
1404 ret = extent_range_uptodate(io_tree, start + length,
1405 start + buf_len - 1);
1406 return ret;
1407}
1408
1409/*
1410 * called by the kthread helper functions to finally call the bio end_io
1411 * functions. This is where read checksum verification actually happens
1412 */
1413static void end_workqueue_fn(struct btrfs_work *work)
1414{
1415 struct bio *bio;
1416 struct end_io_wq *end_io_wq;
1417 struct btrfs_fs_info *fs_info;
1418 int error;
1419
1420 end_io_wq = container_of(work, struct end_io_wq, work);
1421 bio = end_io_wq->bio;
1422 fs_info = end_io_wq->info;
1423
1424 /* metadata bio reads are special because the whole tree block must
1425 * be checksummed at once. This makes sure the entire block is in
1426 * ram and up to date before trying to verify things. For
1427 * blocksize <= pagesize, it is basically a noop
1428 */
1429 if (!(bio->bi_rw & REQ_WRITE) && end_io_wq->metadata &&
1430 !bio_ready_for_csum(bio)) {
1431 btrfs_queue_worker(&fs_info->endio_meta_workers,
1432 &end_io_wq->work);
1433 return;
1434 }
1435 error = end_io_wq->error;
1436 bio->bi_private = end_io_wq->private;
1437 bio->bi_end_io = end_io_wq->end_io;
1438 kfree(end_io_wq);
1439 bio_endio(bio, error);
1440}
1441
1442static int cleaner_kthread(void *arg)
1443{
1444 struct btrfs_root *root = arg;
1445
1446 do {
1447 vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
1448
1449 if (!(root->fs_info->sb->s_flags & MS_RDONLY) &&
1450 mutex_trylock(&root->fs_info->cleaner_mutex)) {
1451 btrfs_run_delayed_iputs(root);
1452 btrfs_clean_old_snapshots(root);
1453 mutex_unlock(&root->fs_info->cleaner_mutex);
1454 }
1455
1456 if (freezing(current)) {
1457 refrigerator();
1458 } else {
1459 set_current_state(TASK_INTERRUPTIBLE);
1460 if (!kthread_should_stop())
1461 schedule();
1462 __set_current_state(TASK_RUNNING);
1463 }
1464 } while (!kthread_should_stop());
1465 return 0;
1466}
1467
1468static int transaction_kthread(void *arg)
1469{
1470 struct btrfs_root *root = arg;
1471 struct btrfs_trans_handle *trans;
1472 struct btrfs_transaction *cur;
1473 u64 transid;
1474 unsigned long now;
1475 unsigned long delay;
1476 int ret;
1477
1478 do {
1479 delay = HZ * 30;
1480 vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
1481 mutex_lock(&root->fs_info->transaction_kthread_mutex);
1482
1483 spin_lock(&root->fs_info->new_trans_lock);
1484 cur = root->fs_info->running_transaction;
1485 if (!cur) {
1486 spin_unlock(&root->fs_info->new_trans_lock);
1487 goto sleep;
1488 }
1489
1490 now = get_seconds();
1491 if (!cur->blocked &&
1492 (now < cur->start_time || now - cur->start_time < 30)) {
1493 spin_unlock(&root->fs_info->new_trans_lock);
1494 delay = HZ * 5;
1495 goto sleep;
1496 }
1497 transid = cur->transid;
1498 spin_unlock(&root->fs_info->new_trans_lock);
1499
1500 trans = btrfs_join_transaction(root, 1);
1501 if (transid == trans->transid) {
1502 ret = btrfs_commit_transaction(trans, root);
1503 BUG_ON(ret);
1504 } else {
1505 btrfs_end_transaction(trans, root);
1506 }
1507sleep:
1508 wake_up_process(root->fs_info->cleaner_kthread);
1509 mutex_unlock(&root->fs_info->transaction_kthread_mutex);
1510
1511 if (freezing(current)) {
1512 refrigerator();
1513 } else {
1514 set_current_state(TASK_INTERRUPTIBLE);
1515 if (!kthread_should_stop() &&
1516 !btrfs_transaction_blocked(root->fs_info))
1517 schedule_timeout(delay);
1518 __set_current_state(TASK_RUNNING);
1519 }
1520 } while (!kthread_should_stop());
1521 return 0;
1522}
1523
1524struct btrfs_root *open_ctree(struct super_block *sb,
1525 struct btrfs_fs_devices *fs_devices,
1526 char *options)
1527{
1528 u32 sectorsize;
1529 u32 nodesize;
1530 u32 leafsize;
1531 u32 blocksize;
1532 u32 stripesize;
1533 u64 generation;
1534 u64 features;
1535 struct btrfs_key location;
1536 struct buffer_head *bh;
1537 struct btrfs_root *extent_root = kzalloc(sizeof(struct btrfs_root),
1538 GFP_NOFS);
1539 struct btrfs_root *csum_root = kzalloc(sizeof(struct btrfs_root),
1540 GFP_NOFS);
1541 struct btrfs_root *tree_root = kzalloc(sizeof(struct btrfs_root),
1542 GFP_NOFS);
1543 struct btrfs_fs_info *fs_info = kzalloc(sizeof(*fs_info),
1544 GFP_NOFS);
1545 struct btrfs_root *chunk_root = kzalloc(sizeof(struct btrfs_root),
1546 GFP_NOFS);
1547 struct btrfs_root *dev_root = kzalloc(sizeof(struct btrfs_root),
1548 GFP_NOFS);
1549 struct btrfs_root *log_tree_root;
1550
1551 int ret;
1552 int err = -EINVAL;
1553
1554 struct btrfs_super_block *disk_super;
1555
1556 if (!extent_root || !tree_root || !fs_info ||
1557 !chunk_root || !dev_root || !csum_root) {
1558 err = -ENOMEM;
1559 goto fail;
1560 }
1561
1562 ret = init_srcu_struct(&fs_info->subvol_srcu);
1563 if (ret) {
1564 err = ret;
1565 goto fail;
1566 }
1567
1568 ret = setup_bdi(fs_info, &fs_info->bdi);
1569 if (ret) {
1570 err = ret;
1571 goto fail_srcu;
1572 }
1573
1574 fs_info->btree_inode = new_inode(sb);
1575 if (!fs_info->btree_inode) {
1576 err = -ENOMEM;
1577 goto fail_bdi;
1578 }
1579
1580 INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
1581 INIT_LIST_HEAD(&fs_info->trans_list);
1582 INIT_LIST_HEAD(&fs_info->dead_roots);
1583 INIT_LIST_HEAD(&fs_info->delayed_iputs);
1584 INIT_LIST_HEAD(&fs_info->hashers);
1585 INIT_LIST_HEAD(&fs_info->delalloc_inodes);
1586 INIT_LIST_HEAD(&fs_info->ordered_operations);
1587 INIT_LIST_HEAD(&fs_info->caching_block_groups);
1588 spin_lock_init(&fs_info->delalloc_lock);
1589 spin_lock_init(&fs_info->new_trans_lock);
1590 spin_lock_init(&fs_info->ref_cache_lock);
1591 spin_lock_init(&fs_info->fs_roots_radix_lock);
1592 spin_lock_init(&fs_info->delayed_iput_lock);
1593
1594 init_completion(&fs_info->kobj_unregister);
1595 fs_info->tree_root = tree_root;
1596 fs_info->extent_root = extent_root;
1597 fs_info->csum_root = csum_root;
1598 fs_info->chunk_root = chunk_root;
1599 fs_info->dev_root = dev_root;
1600 fs_info->fs_devices = fs_devices;
1601 INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
1602 INIT_LIST_HEAD(&fs_info->space_info);
1603 btrfs_mapping_init(&fs_info->mapping_tree);
1604 btrfs_init_block_rsv(&fs_info->global_block_rsv);
1605 btrfs_init_block_rsv(&fs_info->delalloc_block_rsv);
1606 btrfs_init_block_rsv(&fs_info->trans_block_rsv);
1607 btrfs_init_block_rsv(&fs_info->chunk_block_rsv);
1608 btrfs_init_block_rsv(&fs_info->empty_block_rsv);
1609 INIT_LIST_HEAD(&fs_info->durable_block_rsv_list);
1610 mutex_init(&fs_info->durable_block_rsv_mutex);
1611 atomic_set(&fs_info->nr_async_submits, 0);
1612 atomic_set(&fs_info->async_delalloc_pages, 0);
1613 atomic_set(&fs_info->async_submit_draining, 0);
1614 atomic_set(&fs_info->nr_async_bios, 0);
1615 fs_info->sb = sb;
1616 fs_info->max_inline = 8192 * 1024;
1617 fs_info->metadata_ratio = 0;
1618
1619 fs_info->thread_pool_size = min_t(unsigned long,
1620 num_online_cpus() + 2, 8);
1621
1622 INIT_LIST_HEAD(&fs_info->ordered_extents);
1623 spin_lock_init(&fs_info->ordered_extent_lock);
1624
1625 sb->s_blocksize = 4096;
1626 sb->s_blocksize_bits = blksize_bits(4096);
1627 sb->s_bdi = &fs_info->bdi;
1628
1629 fs_info->btree_inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
1630 fs_info->btree_inode->i_nlink = 1;
1631 /*
1632 * we set the i_size on the btree inode to the max possible int.
1633 * the real end of the address space is determined by all of
1634 * the devices in the system
1635 */
1636 fs_info->btree_inode->i_size = OFFSET_MAX;
1637 fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
1638 fs_info->btree_inode->i_mapping->backing_dev_info = &fs_info->bdi;
1639
1640 RB_CLEAR_NODE(&BTRFS_I(fs_info->btree_inode)->rb_node);
1641 extent_io_tree_init(&BTRFS_I(fs_info->btree_inode)->io_tree,
1642 fs_info->btree_inode->i_mapping,
1643 GFP_NOFS);
1644 extent_map_tree_init(&BTRFS_I(fs_info->btree_inode)->extent_tree,
1645 GFP_NOFS);
1646
1647 BTRFS_I(fs_info->btree_inode)->io_tree.ops = &btree_extent_io_ops;
1648
1649 BTRFS_I(fs_info->btree_inode)->root = tree_root;
1650 memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
1651 sizeof(struct btrfs_key));
1652 BTRFS_I(fs_info->btree_inode)->dummy_inode = 1;
1653 insert_inode_hash(fs_info->btree_inode);
1654
1655 spin_lock_init(&fs_info->block_group_cache_lock);
1656 fs_info->block_group_cache_tree = RB_ROOT;
1657
1658 extent_io_tree_init(&fs_info->freed_extents[0],
1659 fs_info->btree_inode->i_mapping, GFP_NOFS);
1660 extent_io_tree_init(&fs_info->freed_extents[1],
1661 fs_info->btree_inode->i_mapping, GFP_NOFS);
1662 fs_info->pinned_extents = &fs_info->freed_extents[0];
1663 fs_info->do_barriers = 1;
1664
1665
1666 mutex_init(&fs_info->trans_mutex);
1667 mutex_init(&fs_info->ordered_operations_mutex);
1668 mutex_init(&fs_info->tree_log_mutex);
1669 mutex_init(&fs_info->chunk_mutex);
1670 mutex_init(&fs_info->transaction_kthread_mutex);
1671 mutex_init(&fs_info->cleaner_mutex);
1672 mutex_init(&fs_info->volume_mutex);
1673 init_rwsem(&fs_info->extent_commit_sem);
1674 init_rwsem(&fs_info->cleanup_work_sem);
1675 init_rwsem(&fs_info->subvol_sem);
1676
1677 btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
1678 btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
1679
1680 init_waitqueue_head(&fs_info->transaction_throttle);
1681 init_waitqueue_head(&fs_info->transaction_wait);
1682 init_waitqueue_head(&fs_info->transaction_blocked_wait);
1683 init_waitqueue_head(&fs_info->async_submit_wait);
1684
1685 __setup_root(4096, 4096, 4096, 4096, tree_root,
1686 fs_info, BTRFS_ROOT_TREE_OBJECTID);
1687
1688 bh = btrfs_read_dev_super(fs_devices->latest_bdev);
1689 if (!bh)
1690 goto fail_iput;
1691
1692 memcpy(&fs_info->super_copy, bh->b_data, sizeof(fs_info->super_copy));
1693 memcpy(&fs_info->super_for_commit, &fs_info->super_copy,
1694 sizeof(fs_info->super_for_commit));
1695 brelse(bh);
1696
1697 memcpy(fs_info->fsid, fs_info->super_copy.fsid, BTRFS_FSID_SIZE);
1698
1699 disk_super = &fs_info->super_copy;
1700 if (!btrfs_super_root(disk_super))
1701 goto fail_iput;
1702
1703 ret = btrfs_parse_options(tree_root, options);
1704 if (ret) {
1705 err = ret;
1706 goto fail_iput;
1707 }
1708
1709 features = btrfs_super_incompat_flags(disk_super) &
1710 ~BTRFS_FEATURE_INCOMPAT_SUPP;
1711 if (features) {
1712 printk(KERN_ERR "BTRFS: couldn't mount because of "
1713 "unsupported optional features (%Lx).\n",
1714 (unsigned long long)features);
1715 err = -EINVAL;
1716 goto fail_iput;
1717 }
1718
1719 features = btrfs_super_incompat_flags(disk_super);
1720 if (!(features & BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF)) {
1721 features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
1722 btrfs_set_super_incompat_flags(disk_super, features);
1723 }
1724
1725 features = btrfs_super_compat_ro_flags(disk_super) &
1726 ~BTRFS_FEATURE_COMPAT_RO_SUPP;
1727 if (!(sb->s_flags & MS_RDONLY) && features) {
1728 printk(KERN_ERR "BTRFS: couldn't mount RDWR because of "
1729 "unsupported option features (%Lx).\n",
1730 (unsigned long long)features);
1731 err = -EINVAL;
1732 goto fail_iput;
1733 }
1734
1735 btrfs_init_workers(&fs_info->generic_worker,
1736 "genwork", 1, NULL);
1737
1738 btrfs_init_workers(&fs_info->workers, "worker",
1739 fs_info->thread_pool_size,
1740 &fs_info->generic_worker);
1741
1742 btrfs_init_workers(&fs_info->delalloc_workers, "delalloc",
1743 fs_info->thread_pool_size,
1744 &fs_info->generic_worker);
1745
1746 btrfs_init_workers(&fs_info->submit_workers, "submit",
1747 min_t(u64, fs_devices->num_devices,
1748 fs_info->thread_pool_size),
1749 &fs_info->generic_worker);
1750
1751 /* a higher idle thresh on the submit workers makes it much more
1752 * likely that bios will be send down in a sane order to the
1753 * devices
1754 */
1755 fs_info->submit_workers.idle_thresh = 64;
1756
1757 fs_info->workers.idle_thresh = 16;
1758 fs_info->workers.ordered = 1;
1759
1760 fs_info->delalloc_workers.idle_thresh = 2;
1761 fs_info->delalloc_workers.ordered = 1;
1762
1763 btrfs_init_workers(&fs_info->fixup_workers, "fixup", 1,
1764 &fs_info->generic_worker);
1765 btrfs_init_workers(&fs_info->endio_workers, "endio",
1766 fs_info->thread_pool_size,
1767 &fs_info->generic_worker);
1768 btrfs_init_workers(&fs_info->endio_meta_workers, "endio-meta",
1769 fs_info->thread_pool_size,
1770 &fs_info->generic_worker);
1771 btrfs_init_workers(&fs_info->endio_meta_write_workers,
1772 "endio-meta-write", fs_info->thread_pool_size,
1773 &fs_info->generic_worker);
1774 btrfs_init_workers(&fs_info->endio_write_workers, "endio-write",
1775 fs_info->thread_pool_size,
1776 &fs_info->generic_worker);
1777 btrfs_init_workers(&fs_info->endio_freespace_worker, "freespace-write",
1778 1, &fs_info->generic_worker);
1779
1780 /*
1781 * endios are largely parallel and should have a very
1782 * low idle thresh
1783 */
1784 fs_info->endio_workers.idle_thresh = 4;
1785 fs_info->endio_meta_workers.idle_thresh = 4;
1786
1787 fs_info->endio_write_workers.idle_thresh = 2;
1788 fs_info->endio_meta_write_workers.idle_thresh = 2;
1789
1790 btrfs_start_workers(&fs_info->workers, 1);
1791 btrfs_start_workers(&fs_info->generic_worker, 1);
1792 btrfs_start_workers(&fs_info->submit_workers, 1);
1793 btrfs_start_workers(&fs_info->delalloc_workers, 1);
1794 btrfs_start_workers(&fs_info->fixup_workers, 1);
1795 btrfs_start_workers(&fs_info->endio_workers, 1);
1796 btrfs_start_workers(&fs_info->endio_meta_workers, 1);
1797 btrfs_start_workers(&fs_info->endio_meta_write_workers, 1);
1798 btrfs_start_workers(&fs_info->endio_write_workers, 1);
1799 btrfs_start_workers(&fs_info->endio_freespace_worker, 1);
1800
1801 fs_info->bdi.ra_pages *= btrfs_super_num_devices(disk_super);
1802 fs_info->bdi.ra_pages = max(fs_info->bdi.ra_pages,
1803 4 * 1024 * 1024 / PAGE_CACHE_SIZE);
1804
1805 nodesize = btrfs_super_nodesize(disk_super);
1806 leafsize = btrfs_super_leafsize(disk_super);
1807 sectorsize = btrfs_super_sectorsize(disk_super);
1808 stripesize = btrfs_super_stripesize(disk_super);
1809 tree_root->nodesize = nodesize;
1810 tree_root->leafsize = leafsize;
1811 tree_root->sectorsize = sectorsize;
1812 tree_root->stripesize = stripesize;
1813
1814 sb->s_blocksize = sectorsize;
1815 sb->s_blocksize_bits = blksize_bits(sectorsize);
1816
1817 if (strncmp((char *)(&disk_super->magic), BTRFS_MAGIC,
1818 sizeof(disk_super->magic))) {
1819 printk(KERN_INFO "btrfs: valid FS not found on %s\n", sb->s_id);
1820 goto fail_sb_buffer;
1821 }
1822
1823 mutex_lock(&fs_info->chunk_mutex);
1824 ret = btrfs_read_sys_array(tree_root);
1825 mutex_unlock(&fs_info->chunk_mutex);
1826 if (ret) {
1827 printk(KERN_WARNING "btrfs: failed to read the system "
1828 "array on %s\n", sb->s_id);
1829 goto fail_sb_buffer;
1830 }
1831
1832 blocksize = btrfs_level_size(tree_root,
1833 btrfs_super_chunk_root_level(disk_super));
1834 generation = btrfs_super_chunk_root_generation(disk_super);
1835
1836 __setup_root(nodesize, leafsize, sectorsize, stripesize,
1837 chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
1838
1839 chunk_root->node = read_tree_block(chunk_root,
1840 btrfs_super_chunk_root(disk_super),
1841 blocksize, generation);
1842 BUG_ON(!chunk_root->node);
1843 if (!test_bit(EXTENT_BUFFER_UPTODATE, &chunk_root->node->bflags)) {
1844 printk(KERN_WARNING "btrfs: failed to read chunk root on %s\n",
1845 sb->s_id);
1846 goto fail_chunk_root;
1847 }
1848 btrfs_set_root_node(&chunk_root->root_item, chunk_root->node);
1849 chunk_root->commit_root = btrfs_root_node(chunk_root);
1850
1851 read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
1852 (unsigned long)btrfs_header_chunk_tree_uuid(chunk_root->node),
1853 BTRFS_UUID_SIZE);
1854
1855 mutex_lock(&fs_info->chunk_mutex);
1856 ret = btrfs_read_chunk_tree(chunk_root);
1857 mutex_unlock(&fs_info->chunk_mutex);
1858 if (ret) {
1859 printk(KERN_WARNING "btrfs: failed to read chunk tree on %s\n",
1860 sb->s_id);
1861 goto fail_chunk_root;
1862 }
1863
1864 btrfs_close_extra_devices(fs_devices);
1865
1866 blocksize = btrfs_level_size(tree_root,
1867 btrfs_super_root_level(disk_super));
1868 generation = btrfs_super_generation(disk_super);
1869
1870 tree_root->node = read_tree_block(tree_root,
1871 btrfs_super_root(disk_super),
1872 blocksize, generation);
1873 if (!tree_root->node)
1874 goto fail_chunk_root;
1875 if (!test_bit(EXTENT_BUFFER_UPTODATE, &tree_root->node->bflags)) {
1876 printk(KERN_WARNING "btrfs: failed to read tree root on %s\n",
1877 sb->s_id);
1878 goto fail_tree_root;
1879 }
1880 btrfs_set_root_node(&tree_root->root_item, tree_root->node);
1881 tree_root->commit_root = btrfs_root_node(tree_root);
1882
1883 ret = find_and_setup_root(tree_root, fs_info,
1884 BTRFS_EXTENT_TREE_OBJECTID, extent_root);
1885 if (ret)
1886 goto fail_tree_root;
1887 extent_root->track_dirty = 1;
1888
1889 ret = find_and_setup_root(tree_root, fs_info,
1890 BTRFS_DEV_TREE_OBJECTID, dev_root);
1891 if (ret)
1892 goto fail_extent_root;
1893 dev_root->track_dirty = 1;
1894
1895 ret = find_and_setup_root(tree_root, fs_info,
1896 BTRFS_CSUM_TREE_OBJECTID, csum_root);
1897 if (ret)
1898 goto fail_dev_root;
1899
1900 csum_root->track_dirty = 1;
1901
1902 fs_info->generation = generation;
1903 fs_info->last_trans_committed = generation;
1904 fs_info->data_alloc_profile = (u64)-1;
1905 fs_info->metadata_alloc_profile = (u64)-1;
1906 fs_info->system_alloc_profile = fs_info->metadata_alloc_profile;
1907
1908 ret = btrfs_read_block_groups(extent_root);
1909 if (ret) {
1910 printk(KERN_ERR "Failed to read block groups: %d\n", ret);
1911 goto fail_block_groups;
1912 }
1913
1914 fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root,
1915 "btrfs-cleaner");
1916 if (IS_ERR(fs_info->cleaner_kthread))
1917 goto fail_block_groups;
1918
1919 fs_info->transaction_kthread = kthread_run(transaction_kthread,
1920 tree_root,
1921 "btrfs-transaction");
1922 if (IS_ERR(fs_info->transaction_kthread))
1923 goto fail_cleaner;
1924
1925 if (!btrfs_test_opt(tree_root, SSD) &&
1926 !btrfs_test_opt(tree_root, NOSSD) &&
1927 !fs_info->fs_devices->rotating) {
1928 printk(KERN_INFO "Btrfs detected SSD devices, enabling SSD "
1929 "mode\n");
1930 btrfs_set_opt(fs_info->mount_opt, SSD);
1931 }
1932
1933 if (btrfs_super_log_root(disk_super) != 0) {
1934 u64 bytenr = btrfs_super_log_root(disk_super);
1935
1936 if (fs_devices->rw_devices == 0) {
1937 printk(KERN_WARNING "Btrfs log replay required "
1938 "on RO media\n");
1939 err = -EIO;
1940 goto fail_trans_kthread;
1941 }
1942 blocksize =
1943 btrfs_level_size(tree_root,
1944 btrfs_super_log_root_level(disk_super));
1945
1946 log_tree_root = kzalloc(sizeof(struct btrfs_root), GFP_NOFS);
1947 if (!log_tree_root) {
1948 err = -ENOMEM;
1949 goto fail_trans_kthread;
1950 }
1951
1952 __setup_root(nodesize, leafsize, sectorsize, stripesize,
1953 log_tree_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
1954
1955 log_tree_root->node = read_tree_block(tree_root, bytenr,
1956 blocksize,
1957 generation + 1);
1958 ret = btrfs_recover_log_trees(log_tree_root);
1959 BUG_ON(ret);
1960
1961 if (sb->s_flags & MS_RDONLY) {
1962 ret = btrfs_commit_super(tree_root);
1963 BUG_ON(ret);
1964 }
1965 }
1966
1967 ret = btrfs_find_orphan_roots(tree_root);
1968 BUG_ON(ret);
1969
1970 if (!(sb->s_flags & MS_RDONLY)) {
1971 ret = btrfs_cleanup_fs_roots(fs_info);
1972 BUG_ON(ret);
1973
1974 ret = btrfs_recover_relocation(tree_root);
1975 if (ret < 0) {
1976 printk(KERN_WARNING
1977 "btrfs: failed to recover relocation\n");
1978 err = -EINVAL;
1979 goto fail_trans_kthread;
1980 }
1981 }
1982
1983 location.objectid = BTRFS_FS_TREE_OBJECTID;
1984 location.type = BTRFS_ROOT_ITEM_KEY;
1985 location.offset = (u64)-1;
1986
1987 fs_info->fs_root = btrfs_read_fs_root_no_name(fs_info, &location);
1988 if (!fs_info->fs_root)
1989 goto fail_trans_kthread;
1990 if (IS_ERR(fs_info->fs_root)) {
1991 err = PTR_ERR(fs_info->fs_root);
1992 goto fail_trans_kthread;
1993 }
1994
1995 if (!(sb->s_flags & MS_RDONLY)) {
1996 down_read(&fs_info->cleanup_work_sem);
1997 btrfs_orphan_cleanup(fs_info->fs_root);
1998 btrfs_orphan_cleanup(fs_info->tree_root);
1999 up_read(&fs_info->cleanup_work_sem);
2000 }
2001
2002 return tree_root;
2003
2004fail_trans_kthread:
2005 kthread_stop(fs_info->transaction_kthread);
2006fail_cleaner:
2007 kthread_stop(fs_info->cleaner_kthread);
2008
2009 /*
2010 * make sure we're done with the btree inode before we stop our
2011 * kthreads
2012 */
2013 filemap_write_and_wait(fs_info->btree_inode->i_mapping);
2014 invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
2015
2016fail_block_groups:
2017 btrfs_free_block_groups(fs_info);
2018 free_extent_buffer(csum_root->node);
2019 free_extent_buffer(csum_root->commit_root);
2020fail_dev_root:
2021 free_extent_buffer(dev_root->node);
2022 free_extent_buffer(dev_root->commit_root);
2023fail_extent_root:
2024 free_extent_buffer(extent_root->node);
2025 free_extent_buffer(extent_root->commit_root);
2026fail_tree_root:
2027 free_extent_buffer(tree_root->node);
2028 free_extent_buffer(tree_root->commit_root);
2029fail_chunk_root:
2030 free_extent_buffer(chunk_root->node);
2031 free_extent_buffer(chunk_root->commit_root);
2032fail_sb_buffer:
2033 btrfs_stop_workers(&fs_info->generic_worker);
2034 btrfs_stop_workers(&fs_info->fixup_workers);
2035 btrfs_stop_workers(&fs_info->delalloc_workers);
2036 btrfs_stop_workers(&fs_info->workers);
2037 btrfs_stop_workers(&fs_info->endio_workers);
2038 btrfs_stop_workers(&fs_info->endio_meta_workers);
2039 btrfs_stop_workers(&fs_info->endio_meta_write_workers);
2040 btrfs_stop_workers(&fs_info->endio_write_workers);
2041 btrfs_stop_workers(&fs_info->endio_freespace_worker);
2042 btrfs_stop_workers(&fs_info->submit_workers);
2043fail_iput:
2044 invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
2045 iput(fs_info->btree_inode);
2046
2047 btrfs_close_devices(fs_info->fs_devices);
2048 btrfs_mapping_tree_free(&fs_info->mapping_tree);
2049fail_bdi:
2050 bdi_destroy(&fs_info->bdi);
2051fail_srcu:
2052 cleanup_srcu_struct(&fs_info->subvol_srcu);
2053fail:
2054 kfree(extent_root);
2055 kfree(tree_root);
2056 kfree(fs_info);
2057 kfree(chunk_root);
2058 kfree(dev_root);
2059 kfree(csum_root);
2060 return ERR_PTR(err);
2061}
2062
2063static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate)
2064{
2065 char b[BDEVNAME_SIZE];
2066
2067 if (uptodate) {
2068 set_buffer_uptodate(bh);
2069 } else {
2070 if (!buffer_eopnotsupp(bh) && printk_ratelimit()) {
2071 printk(KERN_WARNING "lost page write due to "
2072 "I/O error on %s\n",
2073 bdevname(bh->b_bdev, b));
2074 }
2075 /* note, we dont' set_buffer_write_io_error because we have
2076 * our own ways of dealing with the IO errors
2077 */
2078 clear_buffer_uptodate(bh);
2079 }
2080 unlock_buffer(bh);
2081 put_bh(bh);
2082}
2083
2084struct buffer_head *btrfs_read_dev_super(struct block_device *bdev)
2085{
2086 struct buffer_head *bh;
2087 struct buffer_head *latest = NULL;
2088 struct btrfs_super_block *super;
2089 int i;
2090 u64 transid = 0;
2091 u64 bytenr;
2092
2093 /* we would like to check all the supers, but that would make
2094 * a btrfs mount succeed after a mkfs from a different FS.
2095 * So, we need to add a special mount option to scan for
2096 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
2097 */
2098 for (i = 0; i < 1; i++) {
2099 bytenr = btrfs_sb_offset(i);
2100 if (bytenr + 4096 >= i_size_read(bdev->bd_inode))
2101 break;
2102 bh = __bread(bdev, bytenr / 4096, 4096);
2103 if (!bh)
2104 continue;
2105
2106 super = (struct btrfs_super_block *)bh->b_data;
2107 if (btrfs_super_bytenr(super) != bytenr ||
2108 strncmp((char *)(&super->magic), BTRFS_MAGIC,
2109 sizeof(super->magic))) {
2110 brelse(bh);
2111 continue;
2112 }
2113
2114 if (!latest || btrfs_super_generation(super) > transid) {
2115 brelse(latest);
2116 latest = bh;
2117 transid = btrfs_super_generation(super);
2118 } else {
2119 brelse(bh);
2120 }
2121 }
2122 return latest;
2123}
2124
2125/*
2126 * this should be called twice, once with wait == 0 and
2127 * once with wait == 1. When wait == 0 is done, all the buffer heads
2128 * we write are pinned.
2129 *
2130 * They are released when wait == 1 is done.
2131 * max_mirrors must be the same for both runs, and it indicates how
2132 * many supers on this one device should be written.
2133 *
2134 * max_mirrors == 0 means to write them all.
2135 */
2136static int write_dev_supers(struct btrfs_device *device,
2137 struct btrfs_super_block *sb,
2138 int do_barriers, int wait, int max_mirrors)
2139{
2140 struct buffer_head *bh;
2141 int i;
2142 int ret;
2143 int errors = 0;
2144 u32 crc;
2145 u64 bytenr;
2146 int last_barrier = 0;
2147
2148 if (max_mirrors == 0)
2149 max_mirrors = BTRFS_SUPER_MIRROR_MAX;
2150
2151 /* make sure only the last submit_bh does a barrier */
2152 if (do_barriers) {
2153 for (i = 0; i < max_mirrors; i++) {
2154 bytenr = btrfs_sb_offset(i);
2155 if (bytenr + BTRFS_SUPER_INFO_SIZE >=
2156 device->total_bytes)
2157 break;
2158 last_barrier = i;
2159 }
2160 }
2161
2162 for (i = 0; i < max_mirrors; i++) {
2163 bytenr = btrfs_sb_offset(i);
2164 if (bytenr + BTRFS_SUPER_INFO_SIZE >= device->total_bytes)
2165 break;
2166
2167 if (wait) {
2168 bh = __find_get_block(device->bdev, bytenr / 4096,
2169 BTRFS_SUPER_INFO_SIZE);
2170 BUG_ON(!bh);
2171 wait_on_buffer(bh);
2172 if (!buffer_uptodate(bh))
2173 errors++;
2174
2175 /* drop our reference */
2176 brelse(bh);
2177
2178 /* drop the reference from the wait == 0 run */
2179 brelse(bh);
2180 continue;
2181 } else {
2182 btrfs_set_super_bytenr(sb, bytenr);
2183
2184 crc = ~(u32)0;
2185 crc = btrfs_csum_data(NULL, (char *)sb +
2186 BTRFS_CSUM_SIZE, crc,
2187 BTRFS_SUPER_INFO_SIZE -
2188 BTRFS_CSUM_SIZE);
2189 btrfs_csum_final(crc, sb->csum);
2190
2191 /*
2192 * one reference for us, and we leave it for the
2193 * caller
2194 */
2195 bh = __getblk(device->bdev, bytenr / 4096,
2196 BTRFS_SUPER_INFO_SIZE);
2197 memcpy(bh->b_data, sb, BTRFS_SUPER_INFO_SIZE);
2198
2199 /* one reference for submit_bh */
2200 get_bh(bh);
2201
2202 set_buffer_uptodate(bh);
2203 lock_buffer(bh);
2204 bh->b_end_io = btrfs_end_buffer_write_sync;
2205 }
2206
2207 if (i == last_barrier && do_barriers && device->barriers) {
2208 ret = submit_bh(WRITE_BARRIER, bh);
2209 if (ret == -EOPNOTSUPP) {
2210 printk("btrfs: disabling barriers on dev %s\n",
2211 device->name);
2212 set_buffer_uptodate(bh);
2213 device->barriers = 0;
2214 /* one reference for submit_bh */
2215 get_bh(bh);
2216 lock_buffer(bh);
2217 ret = submit_bh(WRITE_SYNC, bh);
2218 }
2219 } else {
2220 ret = submit_bh(WRITE_SYNC, bh);
2221 }
2222
2223 if (ret)
2224 errors++;
2225 }
2226 return errors < i ? 0 : -1;
2227}
2228
2229int write_all_supers(struct btrfs_root *root, int max_mirrors)
2230{
2231 struct list_head *head;
2232 struct btrfs_device *dev;
2233 struct btrfs_super_block *sb;
2234 struct btrfs_dev_item *dev_item;
2235 int ret;
2236 int do_barriers;
2237 int max_errors;
2238 int total_errors = 0;
2239 u64 flags;
2240
2241 max_errors = btrfs_super_num_devices(&root->fs_info->super_copy) - 1;
2242 do_barriers = !btrfs_test_opt(root, NOBARRIER);
2243
2244 sb = &root->fs_info->super_for_commit;
2245 dev_item = &sb->dev_item;
2246
2247 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2248 head = &root->fs_info->fs_devices->devices;
2249 list_for_each_entry(dev, head, dev_list) {
2250 if (!dev->bdev) {
2251 total_errors++;
2252 continue;
2253 }
2254 if (!dev->in_fs_metadata || !dev->writeable)
2255 continue;
2256
2257 btrfs_set_stack_device_generation(dev_item, 0);
2258 btrfs_set_stack_device_type(dev_item, dev->type);
2259 btrfs_set_stack_device_id(dev_item, dev->devid);
2260 btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes);
2261 btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used);
2262 btrfs_set_stack_device_io_align(dev_item, dev->io_align);
2263 btrfs_set_stack_device_io_width(dev_item, dev->io_width);
2264 btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
2265 memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
2266 memcpy(dev_item->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
2267
2268 flags = btrfs_super_flags(sb);
2269 btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
2270
2271 ret = write_dev_supers(dev, sb, do_barriers, 0, max_mirrors);
2272 if (ret)
2273 total_errors++;
2274 }
2275 if (total_errors > max_errors) {
2276 printk(KERN_ERR "btrfs: %d errors while writing supers\n",
2277 total_errors);
2278 BUG();
2279 }
2280
2281 total_errors = 0;
2282 list_for_each_entry(dev, head, dev_list) {
2283 if (!dev->bdev)
2284 continue;
2285 if (!dev->in_fs_metadata || !dev->writeable)
2286 continue;
2287
2288 ret = write_dev_supers(dev, sb, do_barriers, 1, max_mirrors);
2289 if (ret)
2290 total_errors++;
2291 }
2292 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2293 if (total_errors > max_errors) {
2294 printk(KERN_ERR "btrfs: %d errors while writing supers\n",
2295 total_errors);
2296 BUG();
2297 }
2298 return 0;
2299}
2300
2301int write_ctree_super(struct btrfs_trans_handle *trans,
2302 struct btrfs_root *root, int max_mirrors)
2303{
2304 int ret;
2305
2306 ret = write_all_supers(root, max_mirrors);
2307 return ret;
2308}
2309
2310int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
2311{
2312 spin_lock(&fs_info->fs_roots_radix_lock);
2313 radix_tree_delete(&fs_info->fs_roots_radix,
2314 (unsigned long)root->root_key.objectid);
2315 spin_unlock(&fs_info->fs_roots_radix_lock);
2316
2317 if (btrfs_root_refs(&root->root_item) == 0)
2318 synchronize_srcu(&fs_info->subvol_srcu);
2319
2320 free_fs_root(root);
2321 return 0;
2322}
2323
2324static void free_fs_root(struct btrfs_root *root)
2325{
2326 WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
2327 if (root->anon_super.s_dev) {
2328 down_write(&root->anon_super.s_umount);
2329 kill_anon_super(&root->anon_super);
2330 }
2331 free_extent_buffer(root->node);
2332 free_extent_buffer(root->commit_root);
2333 kfree(root->name);
2334 kfree(root);
2335}
2336
2337static int del_fs_roots(struct btrfs_fs_info *fs_info)
2338{
2339 int ret;
2340 struct btrfs_root *gang[8];
2341 int i;
2342
2343 while (!list_empty(&fs_info->dead_roots)) {
2344 gang[0] = list_entry(fs_info->dead_roots.next,
2345 struct btrfs_root, root_list);
2346 list_del(&gang[0]->root_list);
2347
2348 if (gang[0]->in_radix) {
2349 btrfs_free_fs_root(fs_info, gang[0]);
2350 } else {
2351 free_extent_buffer(gang[0]->node);
2352 free_extent_buffer(gang[0]->commit_root);
2353 kfree(gang[0]);
2354 }
2355 }
2356
2357 while (1) {
2358 ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
2359 (void **)gang, 0,
2360 ARRAY_SIZE(gang));
2361 if (!ret)
2362 break;
2363 for (i = 0; i < ret; i++)
2364 btrfs_free_fs_root(fs_info, gang[i]);
2365 }
2366 return 0;
2367}
2368
2369int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
2370{
2371 u64 root_objectid = 0;
2372 struct btrfs_root *gang[8];
2373 int i;
2374 int ret;
2375
2376 while (1) {
2377 ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
2378 (void **)gang, root_objectid,
2379 ARRAY_SIZE(gang));
2380 if (!ret)
2381 break;
2382
2383 root_objectid = gang[ret - 1]->root_key.objectid + 1;
2384 for (i = 0; i < ret; i++) {
2385 root_objectid = gang[i]->root_key.objectid;
2386 btrfs_orphan_cleanup(gang[i]);
2387 }
2388 root_objectid++;
2389 }
2390 return 0;
2391}
2392
2393int btrfs_commit_super(struct btrfs_root *root)
2394{
2395 struct btrfs_trans_handle *trans;
2396 int ret;
2397
2398 mutex_lock(&root->fs_info->cleaner_mutex);
2399 btrfs_run_delayed_iputs(root);
2400 btrfs_clean_old_snapshots(root);
2401 mutex_unlock(&root->fs_info->cleaner_mutex);
2402
2403 /* wait until ongoing cleanup work done */
2404 down_write(&root->fs_info->cleanup_work_sem);
2405 up_write(&root->fs_info->cleanup_work_sem);
2406
2407 trans = btrfs_join_transaction(root, 1);
2408 ret = btrfs_commit_transaction(trans, root);
2409 BUG_ON(ret);
2410 /* run commit again to drop the original snapshot */
2411 trans = btrfs_join_transaction(root, 1);
2412 btrfs_commit_transaction(trans, root);
2413 ret = btrfs_write_and_wait_transaction(NULL, root);
2414 BUG_ON(ret);
2415
2416 ret = write_ctree_super(NULL, root, 0);
2417 return ret;
2418}
2419
2420int close_ctree(struct btrfs_root *root)
2421{
2422 struct btrfs_fs_info *fs_info = root->fs_info;
2423 int ret;
2424
2425 fs_info->closing = 1;
2426 smp_mb();
2427
2428 btrfs_put_block_group_cache(fs_info);
2429 if (!(fs_info->sb->s_flags & MS_RDONLY)) {
2430 ret = btrfs_commit_super(root);
2431 if (ret)
2432 printk(KERN_ERR "btrfs: commit super ret %d\n", ret);
2433 }
2434
2435 kthread_stop(root->fs_info->transaction_kthread);
2436 kthread_stop(root->fs_info->cleaner_kthread);
2437
2438 fs_info->closing = 2;
2439 smp_mb();
2440
2441 if (fs_info->delalloc_bytes) {
2442 printk(KERN_INFO "btrfs: at unmount delalloc count %llu\n",
2443 (unsigned long long)fs_info->delalloc_bytes);
2444 }
2445 if (fs_info->total_ref_cache_size) {
2446 printk(KERN_INFO "btrfs: at umount reference cache size %llu\n",
2447 (unsigned long long)fs_info->total_ref_cache_size);
2448 }
2449
2450 free_extent_buffer(fs_info->extent_root->node);
2451 free_extent_buffer(fs_info->extent_root->commit_root);
2452 free_extent_buffer(fs_info->tree_root->node);
2453 free_extent_buffer(fs_info->tree_root->commit_root);
2454 free_extent_buffer(root->fs_info->chunk_root->node);
2455 free_extent_buffer(root->fs_info->chunk_root->commit_root);
2456 free_extent_buffer(root->fs_info->dev_root->node);
2457 free_extent_buffer(root->fs_info->dev_root->commit_root);
2458 free_extent_buffer(root->fs_info->csum_root->node);
2459 free_extent_buffer(root->fs_info->csum_root->commit_root);
2460
2461 btrfs_free_block_groups(root->fs_info);
2462
2463 del_fs_roots(fs_info);
2464
2465 iput(fs_info->btree_inode);
2466
2467 btrfs_stop_workers(&fs_info->generic_worker);
2468 btrfs_stop_workers(&fs_info->fixup_workers);
2469 btrfs_stop_workers(&fs_info->delalloc_workers);
2470 btrfs_stop_workers(&fs_info->workers);
2471 btrfs_stop_workers(&fs_info->endio_workers);
2472 btrfs_stop_workers(&fs_info->endio_meta_workers);
2473 btrfs_stop_workers(&fs_info->endio_meta_write_workers);
2474 btrfs_stop_workers(&fs_info->endio_write_workers);
2475 btrfs_stop_workers(&fs_info->endio_freespace_worker);
2476 btrfs_stop_workers(&fs_info->submit_workers);
2477
2478 btrfs_close_devices(fs_info->fs_devices);
2479 btrfs_mapping_tree_free(&fs_info->mapping_tree);
2480
2481 bdi_destroy(&fs_info->bdi);
2482 cleanup_srcu_struct(&fs_info->subvol_srcu);
2483
2484 kfree(fs_info->extent_root);
2485 kfree(fs_info->tree_root);
2486 kfree(fs_info->chunk_root);
2487 kfree(fs_info->dev_root);
2488 kfree(fs_info->csum_root);
2489 return 0;
2490}
2491
2492int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid)
2493{
2494 int ret;
2495 struct inode *btree_inode = buf->first_page->mapping->host;
2496
2497 ret = extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree, buf,
2498 NULL);
2499 if (!ret)
2500 return ret;
2501
2502 ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf,
2503 parent_transid);
2504 return !ret;
2505}
2506
2507int btrfs_set_buffer_uptodate(struct extent_buffer *buf)
2508{
2509 struct inode *btree_inode = buf->first_page->mapping->host;
2510 return set_extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree,
2511 buf);
2512}
2513
2514void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
2515{
2516 struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
2517 u64 transid = btrfs_header_generation(buf);
2518 struct inode *btree_inode = root->fs_info->btree_inode;
2519 int was_dirty;
2520
2521 btrfs_assert_tree_locked(buf);
2522 if (transid != root->fs_info->generation) {
2523 printk(KERN_CRIT "btrfs transid mismatch buffer %llu, "
2524 "found %llu running %llu\n",
2525 (unsigned long long)buf->start,
2526 (unsigned long long)transid,
2527 (unsigned long long)root->fs_info->generation);
2528 WARN_ON(1);
2529 }
2530 was_dirty = set_extent_buffer_dirty(&BTRFS_I(btree_inode)->io_tree,
2531 buf);
2532 if (!was_dirty) {
2533 spin_lock(&root->fs_info->delalloc_lock);
2534 root->fs_info->dirty_metadata_bytes += buf->len;
2535 spin_unlock(&root->fs_info->delalloc_lock);
2536 }
2537}
2538
2539void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
2540{
2541 /*
2542 * looks as though older kernels can get into trouble with
2543 * this code, they end up stuck in balance_dirty_pages forever
2544 */
2545 u64 num_dirty;
2546 unsigned long thresh = 32 * 1024 * 1024;
2547
2548 if (current->flags & PF_MEMALLOC)
2549 return;
2550
2551 num_dirty = root->fs_info->dirty_metadata_bytes;
2552
2553 if (num_dirty > thresh) {
2554 balance_dirty_pages_ratelimited_nr(
2555 root->fs_info->btree_inode->i_mapping, 1);
2556 }
2557 return;
2558}
2559
2560int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid)
2561{
2562 struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
2563 int ret;
2564 ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
2565 if (ret == 0)
2566 set_bit(EXTENT_BUFFER_UPTODATE, &buf->bflags);
2567 return ret;
2568}
2569
2570int btree_lock_page_hook(struct page *page)
2571{
2572 struct inode *inode = page->mapping->host;
2573 struct btrfs_root *root = BTRFS_I(inode)->root;
2574 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2575 struct extent_buffer *eb;
2576 unsigned long len;
2577 u64 bytenr = page_offset(page);
2578
2579 if (page->private == EXTENT_PAGE_PRIVATE)
2580 goto out;
2581
2582 len = page->private >> 2;
2583 eb = find_extent_buffer(io_tree, bytenr, len, GFP_NOFS);
2584 if (!eb)
2585 goto out;
2586
2587 btrfs_tree_lock(eb);
2588 btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
2589
2590 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) {
2591 spin_lock(&root->fs_info->delalloc_lock);
2592 if (root->fs_info->dirty_metadata_bytes >= eb->len)
2593 root->fs_info->dirty_metadata_bytes -= eb->len;
2594 else
2595 WARN_ON(1);
2596 spin_unlock(&root->fs_info->delalloc_lock);
2597 }
2598
2599 btrfs_tree_unlock(eb);
2600 free_extent_buffer(eb);
2601out:
2602 lock_page(page);
2603 return 0;
2604}
2605
2606static struct extent_io_ops btree_extent_io_ops = {
2607 .write_cache_pages_lock_hook = btree_lock_page_hook,
2608 .readpage_end_io_hook = btree_readpage_end_io_hook,
2609 .submit_bio_hook = btree_submit_bio_hook,
2610 /* note we're sharing with inode.c for the merge bio hook */
2611 .merge_bio_hook = btrfs_merge_bio_hook,
2612};
Linux 6.x block layer and io_uring tree(s)