2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
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>
37 #include "transaction.h"
38 #include "btrfs_inode.h"
40 #include "print-tree.h"
41 #include "async-thread.h"
44 #include "free-space-cache.h"
45 #include "inode-map.h"
46 #include "check-integrity.h"
47 #include "rcu-string.h"
48 #include "dev-replace.h"
51 #include <asm/cpufeature.h>
54 static struct extent_io_ops btree_extent_io_ops;
55 static void end_workqueue_fn(struct btrfs_work *work);
56 static void free_fs_root(struct btrfs_root *root);
57 static int btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
59 static void btrfs_destroy_ordered_operations(struct btrfs_root *root);
60 static void btrfs_destroy_ordered_extents(struct btrfs_root *root);
61 static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
62 struct btrfs_root *root);
63 static void btrfs_destroy_pending_snapshots(struct btrfs_transaction *t);
64 static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
65 static int btrfs_destroy_marked_extents(struct btrfs_root *root,
66 struct extent_io_tree *dirty_pages,
68 static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
69 struct extent_io_tree *pinned_extents);
72 * end_io_wq structs are used to do processing in task context when an IO is
73 * complete. This is used during reads to verify checksums, and it is used
74 * by writes to insert metadata for new file extents after IO is complete.
80 struct btrfs_fs_info *info;
83 struct list_head list;
84 struct btrfs_work work;
88 * async submit bios are used to offload expensive checksumming
89 * onto the worker threads. They checksum file and metadata bios
90 * just before they are sent down the IO stack.
92 struct async_submit_bio {
95 struct list_head list;
96 extent_submit_bio_hook_t *submit_bio_start;
97 extent_submit_bio_hook_t *submit_bio_done;
100 unsigned long bio_flags;
102 * bio_offset is optional, can be used if the pages in the bio
103 * can't tell us where in the file the bio should go
106 struct btrfs_work work;
111 * Lockdep class keys for extent_buffer->lock's in this root. For a given
112 * eb, the lockdep key is determined by the btrfs_root it belongs to and
113 * the level the eb occupies in the tree.
115 * Different roots are used for different purposes and may nest inside each
116 * other and they require separate keysets. As lockdep keys should be
117 * static, assign keysets according to the purpose of the root as indicated
118 * by btrfs_root->objectid. This ensures that all special purpose roots
119 * have separate keysets.
121 * Lock-nesting across peer nodes is always done with the immediate parent
122 * node locked thus preventing deadlock. As lockdep doesn't know this, use
123 * subclass to avoid triggering lockdep warning in such cases.
125 * The key is set by the readpage_end_io_hook after the buffer has passed
126 * csum validation but before the pages are unlocked. It is also set by
127 * btrfs_init_new_buffer on freshly allocated blocks.
129 * We also add a check to make sure the highest level of the tree is the
130 * same as our lockdep setup here. If BTRFS_MAX_LEVEL changes, this code
131 * needs update as well.
133 #ifdef CONFIG_DEBUG_LOCK_ALLOC
134 # if BTRFS_MAX_LEVEL != 8
138 static struct btrfs_lockdep_keyset {
139 u64 id; /* root objectid */
140 const char *name_stem; /* lock name stem */
141 char names[BTRFS_MAX_LEVEL + 1][20];
142 struct lock_class_key keys[BTRFS_MAX_LEVEL + 1];
143 } btrfs_lockdep_keysets[] = {
144 { .id = BTRFS_ROOT_TREE_OBJECTID, .name_stem = "root" },
145 { .id = BTRFS_EXTENT_TREE_OBJECTID, .name_stem = "extent" },
146 { .id = BTRFS_CHUNK_TREE_OBJECTID, .name_stem = "chunk" },
147 { .id = BTRFS_DEV_TREE_OBJECTID, .name_stem = "dev" },
148 { .id = BTRFS_FS_TREE_OBJECTID, .name_stem = "fs" },
149 { .id = BTRFS_CSUM_TREE_OBJECTID, .name_stem = "csum" },
150 { .id = BTRFS_ORPHAN_OBJECTID, .name_stem = "orphan" },
151 { .id = BTRFS_TREE_LOG_OBJECTID, .name_stem = "log" },
152 { .id = BTRFS_TREE_RELOC_OBJECTID, .name_stem = "treloc" },
153 { .id = BTRFS_DATA_RELOC_TREE_OBJECTID, .name_stem = "dreloc" },
154 { .id = 0, .name_stem = "tree" },
157 void __init btrfs_init_lockdep(void)
161 /* initialize lockdep class names */
162 for (i = 0; i < ARRAY_SIZE(btrfs_lockdep_keysets); i++) {
163 struct btrfs_lockdep_keyset *ks = &btrfs_lockdep_keysets[i];
165 for (j = 0; j < ARRAY_SIZE(ks->names); j++)
166 snprintf(ks->names[j], sizeof(ks->names[j]),
167 "btrfs-%s-%02d", ks->name_stem, j);
171 void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb,
174 struct btrfs_lockdep_keyset *ks;
176 BUG_ON(level >= ARRAY_SIZE(ks->keys));
178 /* find the matching keyset, id 0 is the default entry */
179 for (ks = btrfs_lockdep_keysets; ks->id; ks++)
180 if (ks->id == objectid)
183 lockdep_set_class_and_name(&eb->lock,
184 &ks->keys[level], ks->names[level]);
190 * extents on the btree inode are pretty simple, there's one extent
191 * that covers the entire device
193 static struct extent_map *btree_get_extent(struct inode *inode,
194 struct page *page, size_t pg_offset, u64 start, u64 len,
197 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
198 struct extent_map *em;
201 read_lock(&em_tree->lock);
202 em = lookup_extent_mapping(em_tree, start, len);
205 BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
206 read_unlock(&em_tree->lock);
209 read_unlock(&em_tree->lock);
211 em = alloc_extent_map();
213 em = ERR_PTR(-ENOMEM);
218 em->block_len = (u64)-1;
220 em->bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
222 write_lock(&em_tree->lock);
223 ret = add_extent_mapping(em_tree, em);
224 if (ret == -EEXIST) {
226 em = lookup_extent_mapping(em_tree, start, len);
233 write_unlock(&em_tree->lock);
239 u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len)
241 return crc32c(seed, data, len);
244 void btrfs_csum_final(u32 crc, char *result)
246 put_unaligned_le32(~crc, result);
250 * compute the csum for a btree block, and either verify it or write it
251 * into the csum field of the block.
253 static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
256 u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
259 unsigned long cur_len;
260 unsigned long offset = BTRFS_CSUM_SIZE;
262 unsigned long map_start;
263 unsigned long map_len;
266 unsigned long inline_result;
268 len = buf->len - offset;
270 err = map_private_extent_buffer(buf, offset, 32,
271 &kaddr, &map_start, &map_len);
274 cur_len = min(len, map_len - (offset - map_start));
275 crc = btrfs_csum_data(root, kaddr + offset - map_start,
280 if (csum_size > sizeof(inline_result)) {
281 result = kzalloc(csum_size * sizeof(char), GFP_NOFS);
285 result = (char *)&inline_result;
288 btrfs_csum_final(crc, result);
291 if (memcmp_extent_buffer(buf, result, 0, csum_size)) {
294 memcpy(&found, result, csum_size);
296 read_extent_buffer(buf, &val, 0, csum_size);
297 printk_ratelimited(KERN_INFO "btrfs: %s checksum verify "
298 "failed on %llu wanted %X found %X "
300 root->fs_info->sb->s_id,
301 (unsigned long long)buf->start, val, found,
302 btrfs_header_level(buf));
303 if (result != (char *)&inline_result)
308 write_extent_buffer(buf, result, 0, csum_size);
310 if (result != (char *)&inline_result)
316 * we can't consider a given block up to date unless the transid of the
317 * block matches the transid in the parent node's pointer. This is how we
318 * detect blocks that either didn't get written at all or got written
319 * in the wrong place.
321 static int verify_parent_transid(struct extent_io_tree *io_tree,
322 struct extent_buffer *eb, u64 parent_transid,
325 struct extent_state *cached_state = NULL;
328 if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
334 lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1,
336 if (extent_buffer_uptodate(eb) &&
337 btrfs_header_generation(eb) == parent_transid) {
341 printk_ratelimited("parent transid verify failed on %llu wanted %llu "
343 (unsigned long long)eb->start,
344 (unsigned long long)parent_transid,
345 (unsigned long long)btrfs_header_generation(eb));
347 clear_extent_buffer_uptodate(eb);
349 unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
350 &cached_state, GFP_NOFS);
355 * helper to read a given tree block, doing retries as required when
356 * the checksums don't match and we have alternate mirrors to try.
358 static int btree_read_extent_buffer_pages(struct btrfs_root *root,
359 struct extent_buffer *eb,
360 u64 start, u64 parent_transid)
362 struct extent_io_tree *io_tree;
367 int failed_mirror = 0;
369 clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
370 io_tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree;
372 ret = read_extent_buffer_pages(io_tree, eb, start,
374 btree_get_extent, mirror_num);
376 if (!verify_parent_transid(io_tree, eb,
384 * This buffer's crc is fine, but its contents are corrupted, so
385 * there is no reason to read the other copies, they won't be
388 if (test_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags))
391 num_copies = btrfs_num_copies(root->fs_info,
396 if (!failed_mirror) {
398 failed_mirror = eb->read_mirror;
402 if (mirror_num == failed_mirror)
405 if (mirror_num > num_copies)
409 if (failed && !ret && failed_mirror)
410 repair_eb_io_failure(root, eb, failed_mirror);
416 * checksum a dirty tree block before IO. This has extra checks to make sure
417 * we only fill in the checksum field in the first page of a multi-page block
420 static int csum_dirty_buffer(struct btrfs_root *root, struct page *page)
422 struct extent_io_tree *tree;
423 u64 start = page_offset(page);
425 struct extent_buffer *eb;
427 tree = &BTRFS_I(page->mapping->host)->io_tree;
429 eb = (struct extent_buffer *)page->private;
430 if (page != eb->pages[0])
432 found_start = btrfs_header_bytenr(eb);
433 if (found_start != start) {
437 if (!PageUptodate(page)) {
441 csum_tree_block(root, eb, 0);
445 static int check_tree_block_fsid(struct btrfs_root *root,
446 struct extent_buffer *eb)
448 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
449 u8 fsid[BTRFS_UUID_SIZE];
452 read_extent_buffer(eb, fsid, (unsigned long)btrfs_header_fsid(eb),
455 if (!memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE)) {
459 fs_devices = fs_devices->seed;
464 #define CORRUPT(reason, eb, root, slot) \
465 printk(KERN_CRIT "btrfs: corrupt leaf, %s: block=%llu," \
466 "root=%llu, slot=%d\n", reason, \
467 (unsigned long long)btrfs_header_bytenr(eb), \
468 (unsigned long long)root->objectid, slot)
470 static noinline int check_leaf(struct btrfs_root *root,
471 struct extent_buffer *leaf)
473 struct btrfs_key key;
474 struct btrfs_key leaf_key;
475 u32 nritems = btrfs_header_nritems(leaf);
481 /* Check the 0 item */
482 if (btrfs_item_offset_nr(leaf, 0) + btrfs_item_size_nr(leaf, 0) !=
483 BTRFS_LEAF_DATA_SIZE(root)) {
484 CORRUPT("invalid item offset size pair", leaf, root, 0);
489 * Check to make sure each items keys are in the correct order and their
490 * offsets make sense. We only have to loop through nritems-1 because
491 * we check the current slot against the next slot, which verifies the
492 * next slot's offset+size makes sense and that the current's slot
495 for (slot = 0; slot < nritems - 1; slot++) {
496 btrfs_item_key_to_cpu(leaf, &leaf_key, slot);
497 btrfs_item_key_to_cpu(leaf, &key, slot + 1);
499 /* Make sure the keys are in the right order */
500 if (btrfs_comp_cpu_keys(&leaf_key, &key) >= 0) {
501 CORRUPT("bad key order", leaf, root, slot);
506 * Make sure the offset and ends are right, remember that the
507 * item data starts at the end of the leaf and grows towards the
510 if (btrfs_item_offset_nr(leaf, slot) !=
511 btrfs_item_end_nr(leaf, slot + 1)) {
512 CORRUPT("slot offset bad", leaf, root, slot);
517 * Check to make sure that we don't point outside of the leaf,
518 * just incase all the items are consistent to eachother, but
519 * all point outside of the leaf.
521 if (btrfs_item_end_nr(leaf, slot) >
522 BTRFS_LEAF_DATA_SIZE(root)) {
523 CORRUPT("slot end outside of leaf", leaf, root, slot);
531 struct extent_buffer *find_eb_for_page(struct extent_io_tree *tree,
532 struct page *page, int max_walk)
534 struct extent_buffer *eb;
535 u64 start = page_offset(page);
539 if (start < max_walk)
542 min_start = start - max_walk;
544 while (start >= min_start) {
545 eb = find_extent_buffer(tree, start, 0);
548 * we found an extent buffer and it contains our page
551 if (eb->start <= target &&
552 eb->start + eb->len > target)
555 /* we found an extent buffer that wasn't for us */
556 free_extent_buffer(eb);
561 start -= PAGE_CACHE_SIZE;
566 static int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
567 struct extent_state *state, int mirror)
569 struct extent_io_tree *tree;
572 struct extent_buffer *eb;
573 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
580 tree = &BTRFS_I(page->mapping->host)->io_tree;
581 eb = (struct extent_buffer *)page->private;
583 /* the pending IO might have been the only thing that kept this buffer
584 * in memory. Make sure we have a ref for all this other checks
586 extent_buffer_get(eb);
588 reads_done = atomic_dec_and_test(&eb->io_pages);
592 eb->read_mirror = mirror;
593 if (test_bit(EXTENT_BUFFER_IOERR, &eb->bflags)) {
598 found_start = btrfs_header_bytenr(eb);
599 if (found_start != eb->start) {
600 printk_ratelimited(KERN_INFO "btrfs bad tree block start "
602 (unsigned long long)found_start,
603 (unsigned long long)eb->start);
607 if (check_tree_block_fsid(root, eb)) {
608 printk_ratelimited(KERN_INFO "btrfs bad fsid on block %llu\n",
609 (unsigned long long)eb->start);
613 found_level = btrfs_header_level(eb);
615 btrfs_set_buffer_lockdep_class(btrfs_header_owner(eb),
618 ret = csum_tree_block(root, eb, 1);
625 * If this is a leaf block and it is corrupt, set the corrupt bit so
626 * that we don't try and read the other copies of this block, just
629 if (found_level == 0 && check_leaf(root, eb)) {
630 set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
635 set_extent_buffer_uptodate(eb);
637 if (test_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags)) {
638 clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags);
639 btree_readahead_hook(root, eb, eb->start, ret);
643 clear_extent_buffer_uptodate(eb);
644 free_extent_buffer(eb);
649 static int btree_io_failed_hook(struct page *page, int failed_mirror)
651 struct extent_buffer *eb;
652 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
654 eb = (struct extent_buffer *)page->private;
655 set_bit(EXTENT_BUFFER_IOERR, &eb->bflags);
656 eb->read_mirror = failed_mirror;
657 if (test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags))
658 btree_readahead_hook(root, eb, eb->start, -EIO);
659 return -EIO; /* we fixed nothing */
662 static void end_workqueue_bio(struct bio *bio, int err)
664 struct end_io_wq *end_io_wq = bio->bi_private;
665 struct btrfs_fs_info *fs_info;
667 fs_info = end_io_wq->info;
668 end_io_wq->error = err;
669 end_io_wq->work.func = end_workqueue_fn;
670 end_io_wq->work.flags = 0;
672 if (bio->bi_rw & REQ_WRITE) {
673 if (end_io_wq->metadata == 1)
674 btrfs_queue_worker(&fs_info->endio_meta_write_workers,
676 else if (end_io_wq->metadata == 2)
677 btrfs_queue_worker(&fs_info->endio_freespace_worker,
680 btrfs_queue_worker(&fs_info->endio_write_workers,
683 if (end_io_wq->metadata)
684 btrfs_queue_worker(&fs_info->endio_meta_workers,
687 btrfs_queue_worker(&fs_info->endio_workers,
693 * For the metadata arg you want
696 * 1 - if normal metadta
697 * 2 - if writing to the free space cache area
699 int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
702 struct end_io_wq *end_io_wq;
703 end_io_wq = kmalloc(sizeof(*end_io_wq), GFP_NOFS);
707 end_io_wq->private = bio->bi_private;
708 end_io_wq->end_io = bio->bi_end_io;
709 end_io_wq->info = info;
710 end_io_wq->error = 0;
711 end_io_wq->bio = bio;
712 end_io_wq->metadata = metadata;
714 bio->bi_private = end_io_wq;
715 bio->bi_end_io = end_workqueue_bio;
719 unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info)
721 unsigned long limit = min_t(unsigned long,
722 info->workers.max_workers,
723 info->fs_devices->open_devices);
727 static void run_one_async_start(struct btrfs_work *work)
729 struct async_submit_bio *async;
732 async = container_of(work, struct async_submit_bio, work);
733 ret = async->submit_bio_start(async->inode, async->rw, async->bio,
734 async->mirror_num, async->bio_flags,
740 static void run_one_async_done(struct btrfs_work *work)
742 struct btrfs_fs_info *fs_info;
743 struct async_submit_bio *async;
746 async = container_of(work, struct async_submit_bio, work);
747 fs_info = BTRFS_I(async->inode)->root->fs_info;
749 limit = btrfs_async_submit_limit(fs_info);
750 limit = limit * 2 / 3;
752 if (atomic_dec_return(&fs_info->nr_async_submits) < limit &&
753 waitqueue_active(&fs_info->async_submit_wait))
754 wake_up(&fs_info->async_submit_wait);
756 /* If an error occured we just want to clean up the bio and move on */
758 bio_endio(async->bio, async->error);
762 async->submit_bio_done(async->inode, async->rw, async->bio,
763 async->mirror_num, async->bio_flags,
767 static void run_one_async_free(struct btrfs_work *work)
769 struct async_submit_bio *async;
771 async = container_of(work, struct async_submit_bio, work);
775 int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode,
776 int rw, struct bio *bio, int mirror_num,
777 unsigned long bio_flags,
779 extent_submit_bio_hook_t *submit_bio_start,
780 extent_submit_bio_hook_t *submit_bio_done)
782 struct async_submit_bio *async;
784 async = kmalloc(sizeof(*async), GFP_NOFS);
788 async->inode = inode;
791 async->mirror_num = mirror_num;
792 async->submit_bio_start = submit_bio_start;
793 async->submit_bio_done = submit_bio_done;
795 async->work.func = run_one_async_start;
796 async->work.ordered_func = run_one_async_done;
797 async->work.ordered_free = run_one_async_free;
799 async->work.flags = 0;
800 async->bio_flags = bio_flags;
801 async->bio_offset = bio_offset;
805 atomic_inc(&fs_info->nr_async_submits);
808 btrfs_set_work_high_prio(&async->work);
810 btrfs_queue_worker(&fs_info->workers, &async->work);
812 while (atomic_read(&fs_info->async_submit_draining) &&
813 atomic_read(&fs_info->nr_async_submits)) {
814 wait_event(fs_info->async_submit_wait,
815 (atomic_read(&fs_info->nr_async_submits) == 0));
821 static int btree_csum_one_bio(struct bio *bio)
823 struct bio_vec *bvec = bio->bi_io_vec;
825 struct btrfs_root *root;
828 WARN_ON(bio->bi_vcnt <= 0);
829 while (bio_index < bio->bi_vcnt) {
830 root = BTRFS_I(bvec->bv_page->mapping->host)->root;
831 ret = csum_dirty_buffer(root, bvec->bv_page);
840 static int __btree_submit_bio_start(struct inode *inode, int rw,
841 struct bio *bio, int mirror_num,
842 unsigned long bio_flags,
846 * when we're called for a write, we're already in the async
847 * submission context. Just jump into btrfs_map_bio
849 return btree_csum_one_bio(bio);
852 static int __btree_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
853 int mirror_num, unsigned long bio_flags,
859 * when we're called for a write, we're already in the async
860 * submission context. Just jump into btrfs_map_bio
862 ret = btrfs_map_bio(BTRFS_I(inode)->root, rw, bio, mirror_num, 1);
868 static int check_async_write(struct inode *inode, unsigned long bio_flags)
870 if (bio_flags & EXTENT_BIO_TREE_LOG)
879 static int btree_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
880 int mirror_num, unsigned long bio_flags,
883 int async = check_async_write(inode, bio_flags);
886 if (!(rw & REQ_WRITE)) {
888 * called for a read, do the setup so that checksum validation
889 * can happen in the async kernel threads
891 ret = btrfs_bio_wq_end_io(BTRFS_I(inode)->root->fs_info,
895 ret = btrfs_map_bio(BTRFS_I(inode)->root, rw, bio,
898 ret = btree_csum_one_bio(bio);
901 ret = btrfs_map_bio(BTRFS_I(inode)->root, rw, bio,
905 * kthread helpers are used to submit writes so that
906 * checksumming can happen in parallel across all CPUs
908 ret = btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
909 inode, rw, bio, mirror_num, 0,
911 __btree_submit_bio_start,
912 __btree_submit_bio_done);
922 #ifdef CONFIG_MIGRATION
923 static int btree_migratepage(struct address_space *mapping,
924 struct page *newpage, struct page *page,
925 enum migrate_mode mode)
928 * we can't safely write a btree page from here,
929 * we haven't done the locking hook
934 * Buffers may be managed in a filesystem specific way.
935 * We must have no buffers or drop them.
937 if (page_has_private(page) &&
938 !try_to_release_page(page, GFP_KERNEL))
940 return migrate_page(mapping, newpage, page, mode);
945 static int btree_writepages(struct address_space *mapping,
946 struct writeback_control *wbc)
948 struct extent_io_tree *tree;
949 struct btrfs_fs_info *fs_info;
952 tree = &BTRFS_I(mapping->host)->io_tree;
953 if (wbc->sync_mode == WB_SYNC_NONE) {
955 if (wbc->for_kupdate)
958 fs_info = BTRFS_I(mapping->host)->root->fs_info;
959 /* this is a bit racy, but that's ok */
960 ret = percpu_counter_compare(&fs_info->dirty_metadata_bytes,
961 BTRFS_DIRTY_METADATA_THRESH);
965 return btree_write_cache_pages(mapping, wbc);
968 static int btree_readpage(struct file *file, struct page *page)
970 struct extent_io_tree *tree;
971 tree = &BTRFS_I(page->mapping->host)->io_tree;
972 return extent_read_full_page(tree, page, btree_get_extent, 0);
975 static int btree_releasepage(struct page *page, gfp_t gfp_flags)
977 if (PageWriteback(page) || PageDirty(page))
980 * We need to mask out eg. __GFP_HIGHMEM and __GFP_DMA32 as we're doing
981 * slab allocation from alloc_extent_state down the callchain where
982 * it'd hit a BUG_ON as those flags are not allowed.
984 gfp_flags &= ~GFP_SLAB_BUG_MASK;
986 return try_release_extent_buffer(page, gfp_flags);
989 static void btree_invalidatepage(struct page *page, unsigned long offset)
991 struct extent_io_tree *tree;
992 tree = &BTRFS_I(page->mapping->host)->io_tree;
993 extent_invalidatepage(tree, page, offset);
994 btree_releasepage(page, GFP_NOFS);
995 if (PagePrivate(page)) {
996 printk(KERN_WARNING "btrfs warning page private not zero "
997 "on page %llu\n", (unsigned long long)page_offset(page));
998 ClearPagePrivate(page);
999 set_page_private(page, 0);
1000 page_cache_release(page);
1004 static int btree_set_page_dirty(struct page *page)
1007 struct extent_buffer *eb;
1009 BUG_ON(!PagePrivate(page));
1010 eb = (struct extent_buffer *)page->private;
1012 BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
1013 BUG_ON(!atomic_read(&eb->refs));
1014 btrfs_assert_tree_locked(eb);
1016 return __set_page_dirty_nobuffers(page);
1019 static const struct address_space_operations btree_aops = {
1020 .readpage = btree_readpage,
1021 .writepages = btree_writepages,
1022 .releasepage = btree_releasepage,
1023 .invalidatepage = btree_invalidatepage,
1024 #ifdef CONFIG_MIGRATION
1025 .migratepage = btree_migratepage,
1027 .set_page_dirty = btree_set_page_dirty,
1030 int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
1033 struct extent_buffer *buf = NULL;
1034 struct inode *btree_inode = root->fs_info->btree_inode;
1037 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
1040 read_extent_buffer_pages(&BTRFS_I(btree_inode)->io_tree,
1041 buf, 0, WAIT_NONE, btree_get_extent, 0);
1042 free_extent_buffer(buf);
1046 int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr, u32 blocksize,
1047 int mirror_num, struct extent_buffer **eb)
1049 struct extent_buffer *buf = NULL;
1050 struct inode *btree_inode = root->fs_info->btree_inode;
1051 struct extent_io_tree *io_tree = &BTRFS_I(btree_inode)->io_tree;
1054 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
1058 set_bit(EXTENT_BUFFER_READAHEAD, &buf->bflags);
1060 ret = read_extent_buffer_pages(io_tree, buf, 0, WAIT_PAGE_LOCK,
1061 btree_get_extent, mirror_num);
1063 free_extent_buffer(buf);
1067 if (test_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags)) {
1068 free_extent_buffer(buf);
1070 } else if (extent_buffer_uptodate(buf)) {
1073 free_extent_buffer(buf);
1078 struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
1079 u64 bytenr, u32 blocksize)
1081 struct inode *btree_inode = root->fs_info->btree_inode;
1082 struct extent_buffer *eb;
1083 eb = find_extent_buffer(&BTRFS_I(btree_inode)->io_tree,
1088 struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
1089 u64 bytenr, u32 blocksize)
1091 struct inode *btree_inode = root->fs_info->btree_inode;
1092 struct extent_buffer *eb;
1094 eb = alloc_extent_buffer(&BTRFS_I(btree_inode)->io_tree,
1100 int btrfs_write_tree_block(struct extent_buffer *buf)
1102 return filemap_fdatawrite_range(buf->pages[0]->mapping, buf->start,
1103 buf->start + buf->len - 1);
1106 int btrfs_wait_tree_block_writeback(struct extent_buffer *buf)
1108 return filemap_fdatawait_range(buf->pages[0]->mapping,
1109 buf->start, buf->start + buf->len - 1);
1112 struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
1113 u32 blocksize, u64 parent_transid)
1115 struct extent_buffer *buf = NULL;
1118 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
1122 ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
1127 void clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
1128 struct extent_buffer *buf)
1130 struct btrfs_fs_info *fs_info = root->fs_info;
1132 if (btrfs_header_generation(buf) ==
1133 fs_info->running_transaction->transid) {
1134 btrfs_assert_tree_locked(buf);
1136 if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) {
1137 __percpu_counter_add(&fs_info->dirty_metadata_bytes,
1139 fs_info->dirty_metadata_batch);
1140 /* ugh, clear_extent_buffer_dirty needs to lock the page */
1141 btrfs_set_lock_blocking(buf);
1142 clear_extent_buffer_dirty(buf);
1147 static void __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
1148 u32 stripesize, struct btrfs_root *root,
1149 struct btrfs_fs_info *fs_info,
1153 root->commit_root = NULL;
1154 root->sectorsize = sectorsize;
1155 root->nodesize = nodesize;
1156 root->leafsize = leafsize;
1157 root->stripesize = stripesize;
1159 root->track_dirty = 0;
1161 root->orphan_item_inserted = 0;
1162 root->orphan_cleanup_state = 0;
1164 root->objectid = objectid;
1165 root->last_trans = 0;
1166 root->highest_objectid = 0;
1168 root->inode_tree = RB_ROOT;
1169 INIT_RADIX_TREE(&root->delayed_nodes_tree, GFP_ATOMIC);
1170 root->block_rsv = NULL;
1171 root->orphan_block_rsv = NULL;
1173 INIT_LIST_HEAD(&root->dirty_list);
1174 INIT_LIST_HEAD(&root->root_list);
1175 INIT_LIST_HEAD(&root->logged_list[0]);
1176 INIT_LIST_HEAD(&root->logged_list[1]);
1177 spin_lock_init(&root->orphan_lock);
1178 spin_lock_init(&root->inode_lock);
1179 spin_lock_init(&root->accounting_lock);
1180 spin_lock_init(&root->log_extents_lock[0]);
1181 spin_lock_init(&root->log_extents_lock[1]);
1182 mutex_init(&root->objectid_mutex);
1183 mutex_init(&root->log_mutex);
1184 init_waitqueue_head(&root->log_writer_wait);
1185 init_waitqueue_head(&root->log_commit_wait[0]);
1186 init_waitqueue_head(&root->log_commit_wait[1]);
1187 atomic_set(&root->log_commit[0], 0);
1188 atomic_set(&root->log_commit[1], 0);
1189 atomic_set(&root->log_writers, 0);
1190 atomic_set(&root->log_batch, 0);
1191 atomic_set(&root->orphan_inodes, 0);
1192 root->log_transid = 0;
1193 root->last_log_commit = 0;
1194 extent_io_tree_init(&root->dirty_log_pages,
1195 fs_info->btree_inode->i_mapping);
1197 memset(&root->root_key, 0, sizeof(root->root_key));
1198 memset(&root->root_item, 0, sizeof(root->root_item));
1199 memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
1200 memset(&root->root_kobj, 0, sizeof(root->root_kobj));
1201 root->defrag_trans_start = fs_info->generation;
1202 init_completion(&root->kobj_unregister);
1203 root->defrag_running = 0;
1204 root->root_key.objectid = objectid;
1207 spin_lock_init(&root->root_item_lock);
1210 static int __must_check find_and_setup_root(struct btrfs_root *tree_root,
1211 struct btrfs_fs_info *fs_info,
1213 struct btrfs_root *root)
1219 __setup_root(tree_root->nodesize, tree_root->leafsize,
1220 tree_root->sectorsize, tree_root->stripesize,
1221 root, fs_info, objectid);
1222 ret = btrfs_find_last_root(tree_root, objectid,
1223 &root->root_item, &root->root_key);
1229 generation = btrfs_root_generation(&root->root_item);
1230 blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
1231 root->commit_root = NULL;
1232 root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
1233 blocksize, generation);
1234 if (!root->node || !btrfs_buffer_uptodate(root->node, generation, 0)) {
1235 free_extent_buffer(root->node);
1239 root->commit_root = btrfs_root_node(root);
1243 static struct btrfs_root *btrfs_alloc_root(struct btrfs_fs_info *fs_info)
1245 struct btrfs_root *root = kzalloc(sizeof(*root), GFP_NOFS);
1247 root->fs_info = fs_info;
1251 struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
1252 struct btrfs_fs_info *fs_info,
1255 struct extent_buffer *leaf;
1256 struct btrfs_root *tree_root = fs_info->tree_root;
1257 struct btrfs_root *root;
1258 struct btrfs_key key;
1262 root = btrfs_alloc_root(fs_info);
1264 return ERR_PTR(-ENOMEM);
1266 __setup_root(tree_root->nodesize, tree_root->leafsize,
1267 tree_root->sectorsize, tree_root->stripesize,
1268 root, fs_info, objectid);
1269 root->root_key.objectid = objectid;
1270 root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1271 root->root_key.offset = 0;
1273 leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
1274 0, objectid, NULL, 0, 0, 0);
1276 ret = PTR_ERR(leaf);
1280 bytenr = leaf->start;
1281 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
1282 btrfs_set_header_bytenr(leaf, leaf->start);
1283 btrfs_set_header_generation(leaf, trans->transid);
1284 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
1285 btrfs_set_header_owner(leaf, objectid);
1288 write_extent_buffer(leaf, fs_info->fsid,
1289 (unsigned long)btrfs_header_fsid(leaf),
1291 write_extent_buffer(leaf, fs_info->chunk_tree_uuid,
1292 (unsigned long)btrfs_header_chunk_tree_uuid(leaf),
1294 btrfs_mark_buffer_dirty(leaf);
1296 root->commit_root = btrfs_root_node(root);
1297 root->track_dirty = 1;
1300 root->root_item.flags = 0;
1301 root->root_item.byte_limit = 0;
1302 btrfs_set_root_bytenr(&root->root_item, leaf->start);
1303 btrfs_set_root_generation(&root->root_item, trans->transid);
1304 btrfs_set_root_level(&root->root_item, 0);
1305 btrfs_set_root_refs(&root->root_item, 1);
1306 btrfs_set_root_used(&root->root_item, leaf->len);
1307 btrfs_set_root_last_snapshot(&root->root_item, 0);
1308 btrfs_set_root_dirid(&root->root_item, 0);
1309 root->root_item.drop_level = 0;
1311 key.objectid = objectid;
1312 key.type = BTRFS_ROOT_ITEM_KEY;
1314 ret = btrfs_insert_root(trans, tree_root, &key, &root->root_item);
1318 btrfs_tree_unlock(leaf);
1322 return ERR_PTR(ret);
1327 static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
1328 struct btrfs_fs_info *fs_info)
1330 struct btrfs_root *root;
1331 struct btrfs_root *tree_root = fs_info->tree_root;
1332 struct extent_buffer *leaf;
1334 root = btrfs_alloc_root(fs_info);
1336 return ERR_PTR(-ENOMEM);
1338 __setup_root(tree_root->nodesize, tree_root->leafsize,
1339 tree_root->sectorsize, tree_root->stripesize,
1340 root, fs_info, BTRFS_TREE_LOG_OBJECTID);
1342 root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
1343 root->root_key.type = BTRFS_ROOT_ITEM_KEY;
1344 root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
1346 * log trees do not get reference counted because they go away
1347 * before a real commit is actually done. They do store pointers
1348 * to file data extents, and those reference counts still get
1349 * updated (along with back refs to the log tree).
1353 leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 0,
1354 BTRFS_TREE_LOG_OBJECTID, NULL,
1358 return ERR_CAST(leaf);
1361 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
1362 btrfs_set_header_bytenr(leaf, leaf->start);
1363 btrfs_set_header_generation(leaf, trans->transid);
1364 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
1365 btrfs_set_header_owner(leaf, BTRFS_TREE_LOG_OBJECTID);
1368 write_extent_buffer(root->node, root->fs_info->fsid,
1369 (unsigned long)btrfs_header_fsid(root->node),
1371 btrfs_mark_buffer_dirty(root->node);
1372 btrfs_tree_unlock(root->node);
1376 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
1377 struct btrfs_fs_info *fs_info)
1379 struct btrfs_root *log_root;
1381 log_root = alloc_log_tree(trans, fs_info);
1382 if (IS_ERR(log_root))
1383 return PTR_ERR(log_root);
1384 WARN_ON(fs_info->log_root_tree);
1385 fs_info->log_root_tree = log_root;
1389 int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
1390 struct btrfs_root *root)
1392 struct btrfs_root *log_root;
1393 struct btrfs_inode_item *inode_item;
1395 log_root = alloc_log_tree(trans, root->fs_info);
1396 if (IS_ERR(log_root))
1397 return PTR_ERR(log_root);
1399 log_root->last_trans = trans->transid;
1400 log_root->root_key.offset = root->root_key.objectid;
1402 inode_item = &log_root->root_item.inode;
1403 inode_item->generation = cpu_to_le64(1);
1404 inode_item->size = cpu_to_le64(3);
1405 inode_item->nlink = cpu_to_le32(1);
1406 inode_item->nbytes = cpu_to_le64(root->leafsize);
1407 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
1409 btrfs_set_root_node(&log_root->root_item, log_root->node);
1411 WARN_ON(root->log_root);
1412 root->log_root = log_root;
1413 root->log_transid = 0;
1414 root->last_log_commit = 0;
1418 struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
1419 struct btrfs_key *location)
1421 struct btrfs_root *root;
1422 struct btrfs_fs_info *fs_info = tree_root->fs_info;
1423 struct btrfs_path *path;
1424 struct extent_buffer *l;
1430 root = btrfs_alloc_root(fs_info);
1432 return ERR_PTR(-ENOMEM);
1433 if (location->offset == (u64)-1) {
1434 ret = find_and_setup_root(tree_root, fs_info,
1435 location->objectid, root);
1438 return ERR_PTR(ret);
1443 __setup_root(tree_root->nodesize, tree_root->leafsize,
1444 tree_root->sectorsize, tree_root->stripesize,
1445 root, fs_info, location->objectid);
1447 path = btrfs_alloc_path();
1450 return ERR_PTR(-ENOMEM);
1452 ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
1455 slot = path->slots[0];
1456 btrfs_read_root_item(tree_root, l, slot, &root->root_item);
1457 memcpy(&root->root_key, location, sizeof(*location));
1459 btrfs_free_path(path);
1464 return ERR_PTR(ret);
1467 generation = btrfs_root_generation(&root->root_item);
1468 blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
1469 root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
1470 blocksize, generation);
1471 root->commit_root = btrfs_root_node(root);
1472 BUG_ON(!root->node); /* -ENOMEM */
1474 if (location->objectid != BTRFS_TREE_LOG_OBJECTID) {
1476 btrfs_check_and_init_root_item(&root->root_item);
1482 struct btrfs_root *btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
1483 struct btrfs_key *location)
1485 struct btrfs_root *root;
1488 if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
1489 return fs_info->tree_root;
1490 if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
1491 return fs_info->extent_root;
1492 if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
1493 return fs_info->chunk_root;
1494 if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
1495 return fs_info->dev_root;
1496 if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
1497 return fs_info->csum_root;
1498 if (location->objectid == BTRFS_QUOTA_TREE_OBJECTID)
1499 return fs_info->quota_root ? fs_info->quota_root :
1502 spin_lock(&fs_info->fs_roots_radix_lock);
1503 root = radix_tree_lookup(&fs_info->fs_roots_radix,
1504 (unsigned long)location->objectid);
1505 spin_unlock(&fs_info->fs_roots_radix_lock);
1509 root = btrfs_read_fs_root_no_radix(fs_info->tree_root, location);
1513 root->free_ino_ctl = kzalloc(sizeof(*root->free_ino_ctl), GFP_NOFS);
1514 root->free_ino_pinned = kzalloc(sizeof(*root->free_ino_pinned),
1516 if (!root->free_ino_pinned || !root->free_ino_ctl) {
1521 btrfs_init_free_ino_ctl(root);
1522 mutex_init(&root->fs_commit_mutex);
1523 spin_lock_init(&root->cache_lock);
1524 init_waitqueue_head(&root->cache_wait);
1526 ret = get_anon_bdev(&root->anon_dev);
1530 if (btrfs_root_refs(&root->root_item) == 0) {
1535 ret = btrfs_find_orphan_item(fs_info->tree_root, location->objectid);
1539 root->orphan_item_inserted = 1;
1541 ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
1545 spin_lock(&fs_info->fs_roots_radix_lock);
1546 ret = radix_tree_insert(&fs_info->fs_roots_radix,
1547 (unsigned long)root->root_key.objectid,
1552 spin_unlock(&fs_info->fs_roots_radix_lock);
1553 radix_tree_preload_end();
1555 if (ret == -EEXIST) {
1562 ret = btrfs_find_dead_roots(fs_info->tree_root,
1563 root->root_key.objectid);
1568 return ERR_PTR(ret);
1571 static int btrfs_congested_fn(void *congested_data, int bdi_bits)
1573 struct btrfs_fs_info *info = (struct btrfs_fs_info *)congested_data;
1575 struct btrfs_device *device;
1576 struct backing_dev_info *bdi;
1579 list_for_each_entry_rcu(device, &info->fs_devices->devices, dev_list) {
1582 bdi = blk_get_backing_dev_info(device->bdev);
1583 if (bdi && bdi_congested(bdi, bdi_bits)) {
1593 * If this fails, caller must call bdi_destroy() to get rid of the
1596 static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi)
1600 bdi->capabilities = BDI_CAP_MAP_COPY;
1601 err = bdi_setup_and_register(bdi, "btrfs", BDI_CAP_MAP_COPY);
1605 bdi->ra_pages = default_backing_dev_info.ra_pages;
1606 bdi->congested_fn = btrfs_congested_fn;
1607 bdi->congested_data = info;
1612 * called by the kthread helper functions to finally call the bio end_io
1613 * functions. This is where read checksum verification actually happens
1615 static void end_workqueue_fn(struct btrfs_work *work)
1618 struct end_io_wq *end_io_wq;
1619 struct btrfs_fs_info *fs_info;
1622 end_io_wq = container_of(work, struct end_io_wq, work);
1623 bio = end_io_wq->bio;
1624 fs_info = end_io_wq->info;
1626 error = end_io_wq->error;
1627 bio->bi_private = end_io_wq->private;
1628 bio->bi_end_io = end_io_wq->end_io;
1630 bio_endio(bio, error);
1633 static int cleaner_kthread(void *arg)
1635 struct btrfs_root *root = arg;
1638 if (!(root->fs_info->sb->s_flags & MS_RDONLY) &&
1639 mutex_trylock(&root->fs_info->cleaner_mutex)) {
1640 btrfs_run_delayed_iputs(root);
1641 btrfs_clean_old_snapshots(root);
1642 mutex_unlock(&root->fs_info->cleaner_mutex);
1643 btrfs_run_defrag_inodes(root->fs_info);
1646 if (!try_to_freeze()) {
1647 set_current_state(TASK_INTERRUPTIBLE);
1648 if (!kthread_should_stop())
1650 __set_current_state(TASK_RUNNING);
1652 } while (!kthread_should_stop());
1656 static int transaction_kthread(void *arg)
1658 struct btrfs_root *root = arg;
1659 struct btrfs_trans_handle *trans;
1660 struct btrfs_transaction *cur;
1663 unsigned long delay;
1667 cannot_commit = false;
1669 mutex_lock(&root->fs_info->transaction_kthread_mutex);
1671 spin_lock(&root->fs_info->trans_lock);
1672 cur = root->fs_info->running_transaction;
1674 spin_unlock(&root->fs_info->trans_lock);
1678 now = get_seconds();
1679 if (!cur->blocked &&
1680 (now < cur->start_time || now - cur->start_time < 30)) {
1681 spin_unlock(&root->fs_info->trans_lock);
1685 transid = cur->transid;
1686 spin_unlock(&root->fs_info->trans_lock);
1688 /* If the file system is aborted, this will always fail. */
1689 trans = btrfs_attach_transaction(root);
1690 if (IS_ERR(trans)) {
1691 if (PTR_ERR(trans) != -ENOENT)
1692 cannot_commit = true;
1695 if (transid == trans->transid) {
1696 btrfs_commit_transaction(trans, root);
1698 btrfs_end_transaction(trans, root);
1701 wake_up_process(root->fs_info->cleaner_kthread);
1702 mutex_unlock(&root->fs_info->transaction_kthread_mutex);
1704 if (!try_to_freeze()) {
1705 set_current_state(TASK_INTERRUPTIBLE);
1706 if (!kthread_should_stop() &&
1707 (!btrfs_transaction_blocked(root->fs_info) ||
1709 schedule_timeout(delay);
1710 __set_current_state(TASK_RUNNING);
1712 } while (!kthread_should_stop());
1717 * this will find the highest generation in the array of
1718 * root backups. The index of the highest array is returned,
1719 * or -1 if we can't find anything.
1721 * We check to make sure the array is valid by comparing the
1722 * generation of the latest root in the array with the generation
1723 * in the super block. If they don't match we pitch it.
1725 static int find_newest_super_backup(struct btrfs_fs_info *info, u64 newest_gen)
1728 int newest_index = -1;
1729 struct btrfs_root_backup *root_backup;
1732 for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
1733 root_backup = info->super_copy->super_roots + i;
1734 cur = btrfs_backup_tree_root_gen(root_backup);
1735 if (cur == newest_gen)
1739 /* check to see if we actually wrapped around */
1740 if (newest_index == BTRFS_NUM_BACKUP_ROOTS - 1) {
1741 root_backup = info->super_copy->super_roots;
1742 cur = btrfs_backup_tree_root_gen(root_backup);
1743 if (cur == newest_gen)
1746 return newest_index;
1751 * find the oldest backup so we know where to store new entries
1752 * in the backup array. This will set the backup_root_index
1753 * field in the fs_info struct
1755 static void find_oldest_super_backup(struct btrfs_fs_info *info,
1758 int newest_index = -1;
1760 newest_index = find_newest_super_backup(info, newest_gen);
1761 /* if there was garbage in there, just move along */
1762 if (newest_index == -1) {
1763 info->backup_root_index = 0;
1765 info->backup_root_index = (newest_index + 1) % BTRFS_NUM_BACKUP_ROOTS;
1770 * copy all the root pointers into the super backup array.
1771 * this will bump the backup pointer by one when it is
1774 static void backup_super_roots(struct btrfs_fs_info *info)
1777 struct btrfs_root_backup *root_backup;
1780 next_backup = info->backup_root_index;
1781 last_backup = (next_backup + BTRFS_NUM_BACKUP_ROOTS - 1) %
1782 BTRFS_NUM_BACKUP_ROOTS;
1785 * just overwrite the last backup if we're at the same generation
1786 * this happens only at umount
1788 root_backup = info->super_for_commit->super_roots + last_backup;
1789 if (btrfs_backup_tree_root_gen(root_backup) ==
1790 btrfs_header_generation(info->tree_root->node))
1791 next_backup = last_backup;
1793 root_backup = info->super_for_commit->super_roots + next_backup;
1796 * make sure all of our padding and empty slots get zero filled
1797 * regardless of which ones we use today
1799 memset(root_backup, 0, sizeof(*root_backup));
1801 info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;
1803 btrfs_set_backup_tree_root(root_backup, info->tree_root->node->start);
1804 btrfs_set_backup_tree_root_gen(root_backup,
1805 btrfs_header_generation(info->tree_root->node));
1807 btrfs_set_backup_tree_root_level(root_backup,
1808 btrfs_header_level(info->tree_root->node));
1810 btrfs_set_backup_chunk_root(root_backup, info->chunk_root->node->start);
1811 btrfs_set_backup_chunk_root_gen(root_backup,
1812 btrfs_header_generation(info->chunk_root->node));
1813 btrfs_set_backup_chunk_root_level(root_backup,
1814 btrfs_header_level(info->chunk_root->node));
1816 btrfs_set_backup_extent_root(root_backup, info->extent_root->node->start);
1817 btrfs_set_backup_extent_root_gen(root_backup,
1818 btrfs_header_generation(info->extent_root->node));
1819 btrfs_set_backup_extent_root_level(root_backup,
1820 btrfs_header_level(info->extent_root->node));
1823 * we might commit during log recovery, which happens before we set
1824 * the fs_root. Make sure it is valid before we fill it in.
1826 if (info->fs_root && info->fs_root->node) {
1827 btrfs_set_backup_fs_root(root_backup,
1828 info->fs_root->node->start);
1829 btrfs_set_backup_fs_root_gen(root_backup,
1830 btrfs_header_generation(info->fs_root->node));
1831 btrfs_set_backup_fs_root_level(root_backup,
1832 btrfs_header_level(info->fs_root->node));
1835 btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start);
1836 btrfs_set_backup_dev_root_gen(root_backup,
1837 btrfs_header_generation(info->dev_root->node));
1838 btrfs_set_backup_dev_root_level(root_backup,
1839 btrfs_header_level(info->dev_root->node));
1841 btrfs_set_backup_csum_root(root_backup, info->csum_root->node->start);
1842 btrfs_set_backup_csum_root_gen(root_backup,
1843 btrfs_header_generation(info->csum_root->node));
1844 btrfs_set_backup_csum_root_level(root_backup,
1845 btrfs_header_level(info->csum_root->node));
1847 btrfs_set_backup_total_bytes(root_backup,
1848 btrfs_super_total_bytes(info->super_copy));
1849 btrfs_set_backup_bytes_used(root_backup,
1850 btrfs_super_bytes_used(info->super_copy));
1851 btrfs_set_backup_num_devices(root_backup,
1852 btrfs_super_num_devices(info->super_copy));
1855 * if we don't copy this out to the super_copy, it won't get remembered
1856 * for the next commit
1858 memcpy(&info->super_copy->super_roots,
1859 &info->super_for_commit->super_roots,
1860 sizeof(*root_backup) * BTRFS_NUM_BACKUP_ROOTS);
1864 * this copies info out of the root backup array and back into
1865 * the in-memory super block. It is meant to help iterate through
1866 * the array, so you send it the number of backups you've already
1867 * tried and the last backup index you used.
1869 * this returns -1 when it has tried all the backups
1871 static noinline int next_root_backup(struct btrfs_fs_info *info,
1872 struct btrfs_super_block *super,
1873 int *num_backups_tried, int *backup_index)
1875 struct btrfs_root_backup *root_backup;
1876 int newest = *backup_index;
1878 if (*num_backups_tried == 0) {
1879 u64 gen = btrfs_super_generation(super);
1881 newest = find_newest_super_backup(info, gen);
1885 *backup_index = newest;
1886 *num_backups_tried = 1;
1887 } else if (*num_backups_tried == BTRFS_NUM_BACKUP_ROOTS) {
1888 /* we've tried all the backups, all done */
1891 /* jump to the next oldest backup */
1892 newest = (*backup_index + BTRFS_NUM_BACKUP_ROOTS - 1) %
1893 BTRFS_NUM_BACKUP_ROOTS;
1894 *backup_index = newest;
1895 *num_backups_tried += 1;
1897 root_backup = super->super_roots + newest;
1899 btrfs_set_super_generation(super,
1900 btrfs_backup_tree_root_gen(root_backup));
1901 btrfs_set_super_root(super, btrfs_backup_tree_root(root_backup));
1902 btrfs_set_super_root_level(super,
1903 btrfs_backup_tree_root_level(root_backup));
1904 btrfs_set_super_bytes_used(super, btrfs_backup_bytes_used(root_backup));
1907 * fixme: the total bytes and num_devices need to match or we should
1910 btrfs_set_super_total_bytes(super, btrfs_backup_total_bytes(root_backup));
1911 btrfs_set_super_num_devices(super, btrfs_backup_num_devices(root_backup));
1915 /* helper to cleanup tree roots */
1916 static void free_root_pointers(struct btrfs_fs_info *info, int chunk_root)
1918 free_extent_buffer(info->tree_root->node);
1919 free_extent_buffer(info->tree_root->commit_root);
1920 free_extent_buffer(info->dev_root->node);
1921 free_extent_buffer(info->dev_root->commit_root);
1922 free_extent_buffer(info->extent_root->node);
1923 free_extent_buffer(info->extent_root->commit_root);
1924 free_extent_buffer(info->csum_root->node);
1925 free_extent_buffer(info->csum_root->commit_root);
1926 if (info->quota_root) {
1927 free_extent_buffer(info->quota_root->node);
1928 free_extent_buffer(info->quota_root->commit_root);
1931 info->tree_root->node = NULL;
1932 info->tree_root->commit_root = NULL;
1933 info->dev_root->node = NULL;
1934 info->dev_root->commit_root = NULL;
1935 info->extent_root->node = NULL;
1936 info->extent_root->commit_root = NULL;
1937 info->csum_root->node = NULL;
1938 info->csum_root->commit_root = NULL;
1939 if (info->quota_root) {
1940 info->quota_root->node = NULL;
1941 info->quota_root->commit_root = NULL;
1945 free_extent_buffer(info->chunk_root->node);
1946 free_extent_buffer(info->chunk_root->commit_root);
1947 info->chunk_root->node = NULL;
1948 info->chunk_root->commit_root = NULL;
1953 int open_ctree(struct super_block *sb,
1954 struct btrfs_fs_devices *fs_devices,
1964 struct btrfs_key location;
1965 struct buffer_head *bh;
1966 struct btrfs_super_block *disk_super;
1967 struct btrfs_fs_info *fs_info = btrfs_sb(sb);
1968 struct btrfs_root *tree_root;
1969 struct btrfs_root *extent_root;
1970 struct btrfs_root *csum_root;
1971 struct btrfs_root *chunk_root;
1972 struct btrfs_root *dev_root;
1973 struct btrfs_root *quota_root;
1974 struct btrfs_root *log_tree_root;
1977 int num_backups_tried = 0;
1978 int backup_index = 0;
1980 tree_root = fs_info->tree_root = btrfs_alloc_root(fs_info);
1981 extent_root = fs_info->extent_root = btrfs_alloc_root(fs_info);
1982 csum_root = fs_info->csum_root = btrfs_alloc_root(fs_info);
1983 chunk_root = fs_info->chunk_root = btrfs_alloc_root(fs_info);
1984 dev_root = fs_info->dev_root = btrfs_alloc_root(fs_info);
1985 quota_root = fs_info->quota_root = btrfs_alloc_root(fs_info);
1987 if (!tree_root || !extent_root || !csum_root ||
1988 !chunk_root || !dev_root || !quota_root) {
1993 ret = init_srcu_struct(&fs_info->subvol_srcu);
1999 ret = setup_bdi(fs_info, &fs_info->bdi);
2005 ret = percpu_counter_init(&fs_info->dirty_metadata_bytes, 0);
2010 fs_info->dirty_metadata_batch = PAGE_CACHE_SIZE *
2011 (1 + ilog2(nr_cpu_ids));
2013 ret = percpu_counter_init(&fs_info->delalloc_bytes, 0);
2016 goto fail_dirty_metadata_bytes;
2019 fs_info->btree_inode = new_inode(sb);
2020 if (!fs_info->btree_inode) {
2022 goto fail_delalloc_bytes;
2025 mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
2027 INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
2028 INIT_LIST_HEAD(&fs_info->trans_list);
2029 INIT_LIST_HEAD(&fs_info->dead_roots);
2030 INIT_LIST_HEAD(&fs_info->delayed_iputs);
2031 INIT_LIST_HEAD(&fs_info->delalloc_inodes);
2032 INIT_LIST_HEAD(&fs_info->ordered_operations);
2033 INIT_LIST_HEAD(&fs_info->caching_block_groups);
2034 spin_lock_init(&fs_info->delalloc_lock);
2035 spin_lock_init(&fs_info->trans_lock);
2036 spin_lock_init(&fs_info->fs_roots_radix_lock);
2037 spin_lock_init(&fs_info->delayed_iput_lock);
2038 spin_lock_init(&fs_info->defrag_inodes_lock);
2039 spin_lock_init(&fs_info->free_chunk_lock);
2040 spin_lock_init(&fs_info->tree_mod_seq_lock);
2041 rwlock_init(&fs_info->tree_mod_log_lock);
2042 mutex_init(&fs_info->reloc_mutex);
2044 init_completion(&fs_info->kobj_unregister);
2045 INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
2046 INIT_LIST_HEAD(&fs_info->space_info);
2047 INIT_LIST_HEAD(&fs_info->tree_mod_seq_list);
2048 btrfs_mapping_init(&fs_info->mapping_tree);
2049 btrfs_init_block_rsv(&fs_info->global_block_rsv,
2050 BTRFS_BLOCK_RSV_GLOBAL);
2051 btrfs_init_block_rsv(&fs_info->delalloc_block_rsv,
2052 BTRFS_BLOCK_RSV_DELALLOC);
2053 btrfs_init_block_rsv(&fs_info->trans_block_rsv, BTRFS_BLOCK_RSV_TRANS);
2054 btrfs_init_block_rsv(&fs_info->chunk_block_rsv, BTRFS_BLOCK_RSV_CHUNK);
2055 btrfs_init_block_rsv(&fs_info->empty_block_rsv, BTRFS_BLOCK_RSV_EMPTY);
2056 btrfs_init_block_rsv(&fs_info->delayed_block_rsv,
2057 BTRFS_BLOCK_RSV_DELOPS);
2058 atomic_set(&fs_info->nr_async_submits, 0);
2059 atomic_set(&fs_info->async_delalloc_pages, 0);
2060 atomic_set(&fs_info->async_submit_draining, 0);
2061 atomic_set(&fs_info->nr_async_bios, 0);
2062 atomic_set(&fs_info->defrag_running, 0);
2063 atomic_set(&fs_info->tree_mod_seq, 0);
2065 fs_info->max_inline = 8192 * 1024;
2066 fs_info->metadata_ratio = 0;
2067 fs_info->defrag_inodes = RB_ROOT;
2068 fs_info->trans_no_join = 0;
2069 fs_info->free_chunk_space = 0;
2070 fs_info->tree_mod_log = RB_ROOT;
2072 /* readahead state */
2073 INIT_RADIX_TREE(&fs_info->reada_tree, GFP_NOFS & ~__GFP_WAIT);
2074 spin_lock_init(&fs_info->reada_lock);
2076 fs_info->thread_pool_size = min_t(unsigned long,
2077 num_online_cpus() + 2, 8);
2079 INIT_LIST_HEAD(&fs_info->ordered_extents);
2080 spin_lock_init(&fs_info->ordered_extent_lock);
2081 fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root),
2083 if (!fs_info->delayed_root) {
2087 btrfs_init_delayed_root(fs_info->delayed_root);
2089 mutex_init(&fs_info->scrub_lock);
2090 atomic_set(&fs_info->scrubs_running, 0);
2091 atomic_set(&fs_info->scrub_pause_req, 0);
2092 atomic_set(&fs_info->scrubs_paused, 0);
2093 atomic_set(&fs_info->scrub_cancel_req, 0);
2094 init_waitqueue_head(&fs_info->scrub_pause_wait);
2095 init_rwsem(&fs_info->scrub_super_lock);
2096 fs_info->scrub_workers_refcnt = 0;
2097 #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
2098 fs_info->check_integrity_print_mask = 0;
2101 spin_lock_init(&fs_info->balance_lock);
2102 mutex_init(&fs_info->balance_mutex);
2103 atomic_set(&fs_info->balance_running, 0);
2104 atomic_set(&fs_info->balance_pause_req, 0);
2105 atomic_set(&fs_info->balance_cancel_req, 0);
2106 fs_info->balance_ctl = NULL;
2107 init_waitqueue_head(&fs_info->balance_wait_q);
2109 sb->s_blocksize = 4096;
2110 sb->s_blocksize_bits = blksize_bits(4096);
2111 sb->s_bdi = &fs_info->bdi;
2113 fs_info->btree_inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
2114 set_nlink(fs_info->btree_inode, 1);
2116 * we set the i_size on the btree inode to the max possible int.
2117 * the real end of the address space is determined by all of
2118 * the devices in the system
2120 fs_info->btree_inode->i_size = OFFSET_MAX;
2121 fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
2122 fs_info->btree_inode->i_mapping->backing_dev_info = &fs_info->bdi;
2124 RB_CLEAR_NODE(&BTRFS_I(fs_info->btree_inode)->rb_node);
2125 extent_io_tree_init(&BTRFS_I(fs_info->btree_inode)->io_tree,
2126 fs_info->btree_inode->i_mapping);
2127 BTRFS_I(fs_info->btree_inode)->io_tree.track_uptodate = 0;
2128 extent_map_tree_init(&BTRFS_I(fs_info->btree_inode)->extent_tree);
2130 BTRFS_I(fs_info->btree_inode)->io_tree.ops = &btree_extent_io_ops;
2132 BTRFS_I(fs_info->btree_inode)->root = tree_root;
2133 memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
2134 sizeof(struct btrfs_key));
2135 set_bit(BTRFS_INODE_DUMMY,
2136 &BTRFS_I(fs_info->btree_inode)->runtime_flags);
2137 insert_inode_hash(fs_info->btree_inode);
2139 spin_lock_init(&fs_info->block_group_cache_lock);
2140 fs_info->block_group_cache_tree = RB_ROOT;
2141 fs_info->first_logical_byte = (u64)-1;
2143 extent_io_tree_init(&fs_info->freed_extents[0],
2144 fs_info->btree_inode->i_mapping);
2145 extent_io_tree_init(&fs_info->freed_extents[1],
2146 fs_info->btree_inode->i_mapping);
2147 fs_info->pinned_extents = &fs_info->freed_extents[0];
2148 fs_info->do_barriers = 1;
2151 mutex_init(&fs_info->ordered_operations_mutex);
2152 mutex_init(&fs_info->tree_log_mutex);
2153 mutex_init(&fs_info->chunk_mutex);
2154 mutex_init(&fs_info->transaction_kthread_mutex);
2155 mutex_init(&fs_info->cleaner_mutex);
2156 mutex_init(&fs_info->volume_mutex);
2157 init_rwsem(&fs_info->extent_commit_sem);
2158 init_rwsem(&fs_info->cleanup_work_sem);
2159 init_rwsem(&fs_info->subvol_sem);
2160 fs_info->dev_replace.lock_owner = 0;
2161 atomic_set(&fs_info->dev_replace.nesting_level, 0);
2162 mutex_init(&fs_info->dev_replace.lock_finishing_cancel_unmount);
2163 mutex_init(&fs_info->dev_replace.lock_management_lock);
2164 mutex_init(&fs_info->dev_replace.lock);
2166 spin_lock_init(&fs_info->qgroup_lock);
2167 fs_info->qgroup_tree = RB_ROOT;
2168 INIT_LIST_HEAD(&fs_info->dirty_qgroups);
2169 fs_info->qgroup_seq = 1;
2170 fs_info->quota_enabled = 0;
2171 fs_info->pending_quota_state = 0;
2173 btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
2174 btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
2176 init_waitqueue_head(&fs_info->transaction_throttle);
2177 init_waitqueue_head(&fs_info->transaction_wait);
2178 init_waitqueue_head(&fs_info->transaction_blocked_wait);
2179 init_waitqueue_head(&fs_info->async_submit_wait);
2181 __setup_root(4096, 4096, 4096, 4096, tree_root,
2182 fs_info, BTRFS_ROOT_TREE_OBJECTID);
2184 invalidate_bdev(fs_devices->latest_bdev);
2185 bh = btrfs_read_dev_super(fs_devices->latest_bdev);
2191 memcpy(fs_info->super_copy, bh->b_data, sizeof(*fs_info->super_copy));
2192 memcpy(fs_info->super_for_commit, fs_info->super_copy,
2193 sizeof(*fs_info->super_for_commit));
2196 memcpy(fs_info->fsid, fs_info->super_copy->fsid, BTRFS_FSID_SIZE);
2198 disk_super = fs_info->super_copy;
2199 if (!btrfs_super_root(disk_super))
2202 /* check FS state, whether FS is broken. */
2203 fs_info->fs_state |= btrfs_super_flags(disk_super);
2205 ret = btrfs_check_super_valid(fs_info, sb->s_flags & MS_RDONLY);
2207 printk(KERN_ERR "btrfs: superblock contains fatal errors\n");
2213 * run through our array of backup supers and setup
2214 * our ring pointer to the oldest one
2216 generation = btrfs_super_generation(disk_super);
2217 find_oldest_super_backup(fs_info, generation);
2220 * In the long term, we'll store the compression type in the super
2221 * block, and it'll be used for per file compression control.
2223 fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
2225 ret = btrfs_parse_options(tree_root, options);
2231 features = btrfs_super_incompat_flags(disk_super) &
2232 ~BTRFS_FEATURE_INCOMPAT_SUPP;
2234 printk(KERN_ERR "BTRFS: couldn't mount because of "
2235 "unsupported optional features (%Lx).\n",
2236 (unsigned long long)features);
2241 if (btrfs_super_leafsize(disk_super) !=
2242 btrfs_super_nodesize(disk_super)) {
2243 printk(KERN_ERR "BTRFS: couldn't mount because metadata "
2244 "blocksizes don't match. node %d leaf %d\n",
2245 btrfs_super_nodesize(disk_super),
2246 btrfs_super_leafsize(disk_super));
2250 if (btrfs_super_leafsize(disk_super) > BTRFS_MAX_METADATA_BLOCKSIZE) {
2251 printk(KERN_ERR "BTRFS: couldn't mount because metadata "
2252 "blocksize (%d) was too large\n",
2253 btrfs_super_leafsize(disk_super));
2258 features = btrfs_super_incompat_flags(disk_super);
2259 features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
2260 if (tree_root->fs_info->compress_type == BTRFS_COMPRESS_LZO)
2261 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
2264 * flag our filesystem as having big metadata blocks if
2265 * they are bigger than the page size
2267 if (btrfs_super_leafsize(disk_super) > PAGE_CACHE_SIZE) {
2268 if (!(features & BTRFS_FEATURE_INCOMPAT_BIG_METADATA))
2269 printk(KERN_INFO "btrfs flagging fs with big metadata feature\n");
2270 features |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA;
2273 nodesize = btrfs_super_nodesize(disk_super);
2274 leafsize = btrfs_super_leafsize(disk_super);
2275 sectorsize = btrfs_super_sectorsize(disk_super);
2276 stripesize = btrfs_super_stripesize(disk_super);
2277 fs_info->dirty_metadata_batch = leafsize * (1 + ilog2(nr_cpu_ids));
2278 fs_info->delalloc_batch = sectorsize * 512 * (1 + ilog2(nr_cpu_ids));
2281 * mixed block groups end up with duplicate but slightly offset
2282 * extent buffers for the same range. It leads to corruptions
2284 if ((features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) &&
2285 (sectorsize != leafsize)) {
2286 printk(KERN_WARNING "btrfs: unequal leaf/node/sector sizes "
2287 "are not allowed for mixed block groups on %s\n",
2292 btrfs_set_super_incompat_flags(disk_super, features);
2294 features = btrfs_super_compat_ro_flags(disk_super) &
2295 ~BTRFS_FEATURE_COMPAT_RO_SUPP;
2296 if (!(sb->s_flags & MS_RDONLY) && features) {
2297 printk(KERN_ERR "BTRFS: couldn't mount RDWR because of "
2298 "unsupported option features (%Lx).\n",
2299 (unsigned long long)features);
2304 btrfs_init_workers(&fs_info->generic_worker,
2305 "genwork", 1, NULL);
2307 btrfs_init_workers(&fs_info->workers, "worker",
2308 fs_info->thread_pool_size,
2309 &fs_info->generic_worker);
2311 btrfs_init_workers(&fs_info->delalloc_workers, "delalloc",
2312 fs_info->thread_pool_size,
2313 &fs_info->generic_worker);
2315 btrfs_init_workers(&fs_info->flush_workers, "flush_delalloc",
2316 fs_info->thread_pool_size,
2317 &fs_info->generic_worker);
2319 btrfs_init_workers(&fs_info->submit_workers, "submit",
2320 min_t(u64, fs_devices->num_devices,
2321 fs_info->thread_pool_size),
2322 &fs_info->generic_worker);
2324 btrfs_init_workers(&fs_info->caching_workers, "cache",
2325 2, &fs_info->generic_worker);
2327 /* a higher idle thresh on the submit workers makes it much more
2328 * likely that bios will be send down in a sane order to the
2331 fs_info->submit_workers.idle_thresh = 64;
2333 fs_info->workers.idle_thresh = 16;
2334 fs_info->workers.ordered = 1;
2336 fs_info->delalloc_workers.idle_thresh = 2;
2337 fs_info->delalloc_workers.ordered = 1;
2339 btrfs_init_workers(&fs_info->fixup_workers, "fixup", 1,
2340 &fs_info->generic_worker);
2341 btrfs_init_workers(&fs_info->endio_workers, "endio",
2342 fs_info->thread_pool_size,
2343 &fs_info->generic_worker);
2344 btrfs_init_workers(&fs_info->endio_meta_workers, "endio-meta",
2345 fs_info->thread_pool_size,
2346 &fs_info->generic_worker);
2347 btrfs_init_workers(&fs_info->endio_meta_write_workers,
2348 "endio-meta-write", fs_info->thread_pool_size,
2349 &fs_info->generic_worker);
2350 btrfs_init_workers(&fs_info->endio_write_workers, "endio-write",
2351 fs_info->thread_pool_size,
2352 &fs_info->generic_worker);
2353 btrfs_init_workers(&fs_info->endio_freespace_worker, "freespace-write",
2354 1, &fs_info->generic_worker);
2355 btrfs_init_workers(&fs_info->delayed_workers, "delayed-meta",
2356 fs_info->thread_pool_size,
2357 &fs_info->generic_worker);
2358 btrfs_init_workers(&fs_info->readahead_workers, "readahead",
2359 fs_info->thread_pool_size,
2360 &fs_info->generic_worker);
2363 * endios are largely parallel and should have a very
2366 fs_info->endio_workers.idle_thresh = 4;
2367 fs_info->endio_meta_workers.idle_thresh = 4;
2369 fs_info->endio_write_workers.idle_thresh = 2;
2370 fs_info->endio_meta_write_workers.idle_thresh = 2;
2371 fs_info->readahead_workers.idle_thresh = 2;
2374 * btrfs_start_workers can really only fail because of ENOMEM so just
2375 * return -ENOMEM if any of these fail.
2377 ret = btrfs_start_workers(&fs_info->workers);
2378 ret |= btrfs_start_workers(&fs_info->generic_worker);
2379 ret |= btrfs_start_workers(&fs_info->submit_workers);
2380 ret |= btrfs_start_workers(&fs_info->delalloc_workers);
2381 ret |= btrfs_start_workers(&fs_info->fixup_workers);
2382 ret |= btrfs_start_workers(&fs_info->endio_workers);
2383 ret |= btrfs_start_workers(&fs_info->endio_meta_workers);
2384 ret |= btrfs_start_workers(&fs_info->endio_meta_write_workers);
2385 ret |= btrfs_start_workers(&fs_info->endio_write_workers);
2386 ret |= btrfs_start_workers(&fs_info->endio_freespace_worker);
2387 ret |= btrfs_start_workers(&fs_info->delayed_workers);
2388 ret |= btrfs_start_workers(&fs_info->caching_workers);
2389 ret |= btrfs_start_workers(&fs_info->readahead_workers);
2390 ret |= btrfs_start_workers(&fs_info->flush_workers);
2393 goto fail_sb_buffer;
2396 fs_info->bdi.ra_pages *= btrfs_super_num_devices(disk_super);
2397 fs_info->bdi.ra_pages = max(fs_info->bdi.ra_pages,
2398 4 * 1024 * 1024 / PAGE_CACHE_SIZE);
2400 tree_root->nodesize = nodesize;
2401 tree_root->leafsize = leafsize;
2402 tree_root->sectorsize = sectorsize;
2403 tree_root->stripesize = stripesize;
2405 sb->s_blocksize = sectorsize;
2406 sb->s_blocksize_bits = blksize_bits(sectorsize);
2408 if (strncmp((char *)(&disk_super->magic), BTRFS_MAGIC,
2409 sizeof(disk_super->magic))) {
2410 printk(KERN_INFO "btrfs: valid FS not found on %s\n", sb->s_id);
2411 goto fail_sb_buffer;
2414 if (sectorsize != PAGE_SIZE) {
2415 printk(KERN_WARNING "btrfs: Incompatible sector size(%lu) "
2416 "found on %s\n", (unsigned long)sectorsize, sb->s_id);
2417 goto fail_sb_buffer;
2420 mutex_lock(&fs_info->chunk_mutex);
2421 ret = btrfs_read_sys_array(tree_root);
2422 mutex_unlock(&fs_info->chunk_mutex);
2424 printk(KERN_WARNING "btrfs: failed to read the system "
2425 "array on %s\n", sb->s_id);
2426 goto fail_sb_buffer;
2429 blocksize = btrfs_level_size(tree_root,
2430 btrfs_super_chunk_root_level(disk_super));
2431 generation = btrfs_super_chunk_root_generation(disk_super);
2433 __setup_root(nodesize, leafsize, sectorsize, stripesize,
2434 chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
2436 chunk_root->node = read_tree_block(chunk_root,
2437 btrfs_super_chunk_root(disk_super),
2438 blocksize, generation);
2439 BUG_ON(!chunk_root->node); /* -ENOMEM */
2440 if (!test_bit(EXTENT_BUFFER_UPTODATE, &chunk_root->node->bflags)) {
2441 printk(KERN_WARNING "btrfs: failed to read chunk root on %s\n",
2443 goto fail_tree_roots;
2445 btrfs_set_root_node(&chunk_root->root_item, chunk_root->node);
2446 chunk_root->commit_root = btrfs_root_node(chunk_root);
2448 read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
2449 (unsigned long)btrfs_header_chunk_tree_uuid(chunk_root->node),
2452 ret = btrfs_read_chunk_tree(chunk_root);
2454 printk(KERN_WARNING "btrfs: failed to read chunk tree on %s\n",
2456 goto fail_tree_roots;
2460 * keep the device that is marked to be the target device for the
2461 * dev_replace procedure
2463 btrfs_close_extra_devices(fs_info, fs_devices, 0);
2465 if (!fs_devices->latest_bdev) {
2466 printk(KERN_CRIT "btrfs: failed to read devices on %s\n",
2468 goto fail_tree_roots;
2472 blocksize = btrfs_level_size(tree_root,
2473 btrfs_super_root_level(disk_super));
2474 generation = btrfs_super_generation(disk_super);
2476 tree_root->node = read_tree_block(tree_root,
2477 btrfs_super_root(disk_super),
2478 blocksize, generation);
2479 if (!tree_root->node ||
2480 !test_bit(EXTENT_BUFFER_UPTODATE, &tree_root->node->bflags)) {
2481 printk(KERN_WARNING "btrfs: failed to read tree root on %s\n",
2484 goto recovery_tree_root;
2487 btrfs_set_root_node(&tree_root->root_item, tree_root->node);
2488 tree_root->commit_root = btrfs_root_node(tree_root);
2490 ret = find_and_setup_root(tree_root, fs_info,
2491 BTRFS_EXTENT_TREE_OBJECTID, extent_root);
2493 goto recovery_tree_root;
2494 extent_root->track_dirty = 1;
2496 ret = find_and_setup_root(tree_root, fs_info,
2497 BTRFS_DEV_TREE_OBJECTID, dev_root);
2499 goto recovery_tree_root;
2500 dev_root->track_dirty = 1;
2502 ret = find_and_setup_root(tree_root, fs_info,
2503 BTRFS_CSUM_TREE_OBJECTID, csum_root);
2505 goto recovery_tree_root;
2506 csum_root->track_dirty = 1;
2508 ret = find_and_setup_root(tree_root, fs_info,
2509 BTRFS_QUOTA_TREE_OBJECTID, quota_root);
2512 quota_root = fs_info->quota_root = NULL;
2514 quota_root->track_dirty = 1;
2515 fs_info->quota_enabled = 1;
2516 fs_info->pending_quota_state = 1;
2519 fs_info->generation = generation;
2520 fs_info->last_trans_committed = generation;
2522 ret = btrfs_recover_balance(fs_info);
2524 printk(KERN_WARNING "btrfs: failed to recover balance\n");
2525 goto fail_block_groups;
2528 ret = btrfs_init_dev_stats(fs_info);
2530 printk(KERN_ERR "btrfs: failed to init dev_stats: %d\n",
2532 goto fail_block_groups;
2535 ret = btrfs_init_dev_replace(fs_info);
2537 pr_err("btrfs: failed to init dev_replace: %d\n", ret);
2538 goto fail_block_groups;
2541 btrfs_close_extra_devices(fs_info, fs_devices, 1);
2543 ret = btrfs_init_space_info(fs_info);
2545 printk(KERN_ERR "Failed to initial space info: %d\n", ret);
2546 goto fail_block_groups;
2549 ret = btrfs_read_block_groups(extent_root);
2551 printk(KERN_ERR "Failed to read block groups: %d\n", ret);
2552 goto fail_block_groups;
2554 fs_info->num_tolerated_disk_barrier_failures =
2555 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info);
2556 if (fs_info->fs_devices->missing_devices >
2557 fs_info->num_tolerated_disk_barrier_failures &&
2558 !(sb->s_flags & MS_RDONLY)) {
2560 "Btrfs: too many missing devices, writeable mount is not allowed\n");
2561 goto fail_block_groups;
2564 fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root,
2566 if (IS_ERR(fs_info->cleaner_kthread))
2567 goto fail_block_groups;
2569 fs_info->transaction_kthread = kthread_run(transaction_kthread,
2571 "btrfs-transaction");
2572 if (IS_ERR(fs_info->transaction_kthread))
2575 if (!btrfs_test_opt(tree_root, SSD) &&
2576 !btrfs_test_opt(tree_root, NOSSD) &&
2577 !fs_info->fs_devices->rotating) {
2578 printk(KERN_INFO "Btrfs detected SSD devices, enabling SSD "
2580 btrfs_set_opt(fs_info->mount_opt, SSD);
2583 #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
2584 if (btrfs_test_opt(tree_root, CHECK_INTEGRITY)) {
2585 ret = btrfsic_mount(tree_root, fs_devices,
2586 btrfs_test_opt(tree_root,
2587 CHECK_INTEGRITY_INCLUDING_EXTENT_DATA) ?
2589 fs_info->check_integrity_print_mask);
2591 printk(KERN_WARNING "btrfs: failed to initialize"
2592 " integrity check module %s\n", sb->s_id);
2595 ret = btrfs_read_qgroup_config(fs_info);
2597 goto fail_trans_kthread;
2599 /* do not make disk changes in broken FS */
2600 if (btrfs_super_log_root(disk_super) != 0) {
2601 u64 bytenr = btrfs_super_log_root(disk_super);
2603 if (fs_devices->rw_devices == 0) {
2604 printk(KERN_WARNING "Btrfs log replay required "
2610 btrfs_level_size(tree_root,
2611 btrfs_super_log_root_level(disk_super));
2613 log_tree_root = btrfs_alloc_root(fs_info);
2614 if (!log_tree_root) {
2619 __setup_root(nodesize, leafsize, sectorsize, stripesize,
2620 log_tree_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
2622 log_tree_root->node = read_tree_block(tree_root, bytenr,
2625 /* returns with log_tree_root freed on success */
2626 ret = btrfs_recover_log_trees(log_tree_root);
2628 btrfs_error(tree_root->fs_info, ret,
2629 "Failed to recover log tree");
2630 free_extent_buffer(log_tree_root->node);
2631 kfree(log_tree_root);
2632 goto fail_trans_kthread;
2635 if (sb->s_flags & MS_RDONLY) {
2636 ret = btrfs_commit_super(tree_root);
2638 goto fail_trans_kthread;
2642 ret = btrfs_find_orphan_roots(tree_root);
2644 goto fail_trans_kthread;
2646 if (!(sb->s_flags & MS_RDONLY)) {
2647 ret = btrfs_cleanup_fs_roots(fs_info);
2649 goto fail_trans_kthread;
2651 ret = btrfs_recover_relocation(tree_root);
2654 "btrfs: failed to recover relocation\n");
2660 location.objectid = BTRFS_FS_TREE_OBJECTID;
2661 location.type = BTRFS_ROOT_ITEM_KEY;
2662 location.offset = (u64)-1;
2664 fs_info->fs_root = btrfs_read_fs_root_no_name(fs_info, &location);
2665 if (!fs_info->fs_root)
2667 if (IS_ERR(fs_info->fs_root)) {
2668 err = PTR_ERR(fs_info->fs_root);
2672 if (sb->s_flags & MS_RDONLY)
2675 down_read(&fs_info->cleanup_work_sem);
2676 if ((ret = btrfs_orphan_cleanup(fs_info->fs_root)) ||
2677 (ret = btrfs_orphan_cleanup(fs_info->tree_root))) {
2678 up_read(&fs_info->cleanup_work_sem);
2679 close_ctree(tree_root);
2682 up_read(&fs_info->cleanup_work_sem);
2684 ret = btrfs_resume_balance_async(fs_info);
2686 printk(KERN_WARNING "btrfs: failed to resume balance\n");
2687 close_ctree(tree_root);
2691 ret = btrfs_resume_dev_replace_async(fs_info);
2693 pr_warn("btrfs: failed to resume dev_replace\n");
2694 close_ctree(tree_root);
2701 btrfs_free_qgroup_config(fs_info);
2703 kthread_stop(fs_info->transaction_kthread);
2705 kthread_stop(fs_info->cleaner_kthread);
2708 * make sure we're done with the btree inode before we stop our
2711 filemap_write_and_wait(fs_info->btree_inode->i_mapping);
2712 invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
2715 btrfs_free_block_groups(fs_info);
2718 free_root_pointers(fs_info, 1);
2721 btrfs_stop_workers(&fs_info->generic_worker);
2722 btrfs_stop_workers(&fs_info->readahead_workers);
2723 btrfs_stop_workers(&fs_info->fixup_workers);
2724 btrfs_stop_workers(&fs_info->delalloc_workers);
2725 btrfs_stop_workers(&fs_info->workers);
2726 btrfs_stop_workers(&fs_info->endio_workers);
2727 btrfs_stop_workers(&fs_info->endio_meta_workers);
2728 btrfs_stop_workers(&fs_info->endio_meta_write_workers);
2729 btrfs_stop_workers(&fs_info->endio_write_workers);
2730 btrfs_stop_workers(&fs_info->endio_freespace_worker);
2731 btrfs_stop_workers(&fs_info->submit_workers);
2732 btrfs_stop_workers(&fs_info->delayed_workers);
2733 btrfs_stop_workers(&fs_info->caching_workers);
2734 btrfs_stop_workers(&fs_info->flush_workers);
2737 btrfs_mapping_tree_free(&fs_info->mapping_tree);
2739 invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
2740 iput(fs_info->btree_inode);
2741 fail_delalloc_bytes:
2742 percpu_counter_destroy(&fs_info->delalloc_bytes);
2743 fail_dirty_metadata_bytes:
2744 percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
2746 bdi_destroy(&fs_info->bdi);
2748 cleanup_srcu_struct(&fs_info->subvol_srcu);
2750 btrfs_close_devices(fs_info->fs_devices);
2754 if (!btrfs_test_opt(tree_root, RECOVERY))
2755 goto fail_tree_roots;
2757 free_root_pointers(fs_info, 0);
2759 /* don't use the log in recovery mode, it won't be valid */
2760 btrfs_set_super_log_root(disk_super, 0);
2762 /* we can't trust the free space cache either */
2763 btrfs_set_opt(fs_info->mount_opt, CLEAR_CACHE);
2765 ret = next_root_backup(fs_info, fs_info->super_copy,
2766 &num_backups_tried, &backup_index);
2768 goto fail_block_groups;
2769 goto retry_root_backup;
2772 static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate)
2775 set_buffer_uptodate(bh);
2777 struct btrfs_device *device = (struct btrfs_device *)
2780 printk_ratelimited_in_rcu(KERN_WARNING "lost page write due to "
2781 "I/O error on %s\n",
2782 rcu_str_deref(device->name));
2783 /* note, we dont' set_buffer_write_io_error because we have
2784 * our own ways of dealing with the IO errors
2786 clear_buffer_uptodate(bh);
2787 btrfs_dev_stat_inc_and_print(device, BTRFS_DEV_STAT_WRITE_ERRS);
2793 struct buffer_head *btrfs_read_dev_super(struct block_device *bdev)
2795 struct buffer_head *bh;
2796 struct buffer_head *latest = NULL;
2797 struct btrfs_super_block *super;
2802 /* we would like to check all the supers, but that would make
2803 * a btrfs mount succeed after a mkfs from a different FS.
2804 * So, we need to add a special mount option to scan for
2805 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
2807 for (i = 0; i < 1; i++) {
2808 bytenr = btrfs_sb_offset(i);
2809 if (bytenr + 4096 >= i_size_read(bdev->bd_inode))
2811 bh = __bread(bdev, bytenr / 4096, 4096);
2815 super = (struct btrfs_super_block *)bh->b_data;
2816 if (btrfs_super_bytenr(super) != bytenr ||
2817 strncmp((char *)(&super->magic), BTRFS_MAGIC,
2818 sizeof(super->magic))) {
2823 if (!latest || btrfs_super_generation(super) > transid) {
2826 transid = btrfs_super_generation(super);
2835 * this should be called twice, once with wait == 0 and
2836 * once with wait == 1. When wait == 0 is done, all the buffer heads
2837 * we write are pinned.
2839 * They are released when wait == 1 is done.
2840 * max_mirrors must be the same for both runs, and it indicates how
2841 * many supers on this one device should be written.
2843 * max_mirrors == 0 means to write them all.
2845 static int write_dev_supers(struct btrfs_device *device,
2846 struct btrfs_super_block *sb,
2847 int do_barriers, int wait, int max_mirrors)
2849 struct buffer_head *bh;
2856 if (max_mirrors == 0)
2857 max_mirrors = BTRFS_SUPER_MIRROR_MAX;
2859 for (i = 0; i < max_mirrors; i++) {
2860 bytenr = btrfs_sb_offset(i);
2861 if (bytenr + BTRFS_SUPER_INFO_SIZE >= device->total_bytes)
2865 bh = __find_get_block(device->bdev, bytenr / 4096,
2866 BTRFS_SUPER_INFO_SIZE);
2869 if (!buffer_uptodate(bh))
2872 /* drop our reference */
2875 /* drop the reference from the wait == 0 run */
2879 btrfs_set_super_bytenr(sb, bytenr);
2882 crc = btrfs_csum_data(NULL, (char *)sb +
2883 BTRFS_CSUM_SIZE, crc,
2884 BTRFS_SUPER_INFO_SIZE -
2886 btrfs_csum_final(crc, sb->csum);
2889 * one reference for us, and we leave it for the
2892 bh = __getblk(device->bdev, bytenr / 4096,
2893 BTRFS_SUPER_INFO_SIZE);
2894 memcpy(bh->b_data, sb, BTRFS_SUPER_INFO_SIZE);
2896 /* one reference for submit_bh */
2899 set_buffer_uptodate(bh);
2901 bh->b_end_io = btrfs_end_buffer_write_sync;
2902 bh->b_private = device;
2906 * we fua the first super. The others we allow
2909 ret = btrfsic_submit_bh(WRITE_FUA, bh);
2913 return errors < i ? 0 : -1;
2917 * endio for the write_dev_flush, this will wake anyone waiting
2918 * for the barrier when it is done
2920 static void btrfs_end_empty_barrier(struct bio *bio, int err)
2923 if (err == -EOPNOTSUPP)
2924 set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
2925 clear_bit(BIO_UPTODATE, &bio->bi_flags);
2927 if (bio->bi_private)
2928 complete(bio->bi_private);
2933 * trigger flushes for one the devices. If you pass wait == 0, the flushes are
2934 * sent down. With wait == 1, it waits for the previous flush.
2936 * any device where the flush fails with eopnotsupp are flagged as not-barrier
2939 static int write_dev_flush(struct btrfs_device *device, int wait)
2944 if (device->nobarriers)
2948 bio = device->flush_bio;
2952 wait_for_completion(&device->flush_wait);
2954 if (bio_flagged(bio, BIO_EOPNOTSUPP)) {
2955 printk_in_rcu("btrfs: disabling barriers on dev %s\n",
2956 rcu_str_deref(device->name));
2957 device->nobarriers = 1;
2958 } else if (!bio_flagged(bio, BIO_UPTODATE)) {
2960 btrfs_dev_stat_inc_and_print(device,
2961 BTRFS_DEV_STAT_FLUSH_ERRS);
2964 /* drop the reference from the wait == 0 run */
2966 device->flush_bio = NULL;
2972 * one reference for us, and we leave it for the
2975 device->flush_bio = NULL;
2976 bio = bio_alloc(GFP_NOFS, 0);
2980 bio->bi_end_io = btrfs_end_empty_barrier;
2981 bio->bi_bdev = device->bdev;
2982 init_completion(&device->flush_wait);
2983 bio->bi_private = &device->flush_wait;
2984 device->flush_bio = bio;
2987 btrfsic_submit_bio(WRITE_FLUSH, bio);
2993 * send an empty flush down to each device in parallel,
2994 * then wait for them
2996 static int barrier_all_devices(struct btrfs_fs_info *info)
2998 struct list_head *head;
2999 struct btrfs_device *dev;
3000 int errors_send = 0;
3001 int errors_wait = 0;
3004 /* send down all the barriers */
3005 head = &info->fs_devices->devices;
3006 list_for_each_entry_rcu(dev, head, dev_list) {
3011 if (!dev->in_fs_metadata || !dev->writeable)
3014 ret = write_dev_flush(dev, 0);
3019 /* wait for all the barriers */
3020 list_for_each_entry_rcu(dev, head, dev_list) {
3025 if (!dev->in_fs_metadata || !dev->writeable)
3028 ret = write_dev_flush(dev, 1);
3032 if (errors_send > info->num_tolerated_disk_barrier_failures ||
3033 errors_wait > info->num_tolerated_disk_barrier_failures)
3038 int btrfs_calc_num_tolerated_disk_barrier_failures(
3039 struct btrfs_fs_info *fs_info)
3041 struct btrfs_ioctl_space_info space;
3042 struct btrfs_space_info *sinfo;
3043 u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
3044 BTRFS_BLOCK_GROUP_SYSTEM,
3045 BTRFS_BLOCK_GROUP_METADATA,
3046 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
3050 int num_tolerated_disk_barrier_failures =
3051 (int)fs_info->fs_devices->num_devices;
3053 for (i = 0; i < num_types; i++) {
3054 struct btrfs_space_info *tmp;
3058 list_for_each_entry_rcu(tmp, &fs_info->space_info, list) {
3059 if (tmp->flags == types[i]) {
3069 down_read(&sinfo->groups_sem);
3070 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3071 if (!list_empty(&sinfo->block_groups[c])) {
3074 btrfs_get_block_group_info(
3075 &sinfo->block_groups[c], &space);
3076 if (space.total_bytes == 0 ||
3077 space.used_bytes == 0)
3079 flags = space.flags;
3082 * 0: if dup, single or RAID0 is configured for
3083 * any of metadata, system or data, else
3084 * 1: if RAID5 is configured, or if RAID1 or
3085 * RAID10 is configured and only two mirrors
3087 * 2: if RAID6 is configured, else
3088 * num_mirrors - 1: if RAID1 or RAID10 is
3089 * configured and more than
3090 * 2 mirrors are used.
3092 if (num_tolerated_disk_barrier_failures > 0 &&
3093 ((flags & (BTRFS_BLOCK_GROUP_DUP |
3094 BTRFS_BLOCK_GROUP_RAID0)) ||
3095 ((flags & BTRFS_BLOCK_GROUP_PROFILE_MASK)
3097 num_tolerated_disk_barrier_failures = 0;
3098 else if (num_tolerated_disk_barrier_failures > 1
3100 (flags & (BTRFS_BLOCK_GROUP_RAID1 |
3101 BTRFS_BLOCK_GROUP_RAID10)))
3102 num_tolerated_disk_barrier_failures = 1;
3105 up_read(&sinfo->groups_sem);
3108 return num_tolerated_disk_barrier_failures;
3111 int write_all_supers(struct btrfs_root *root, int max_mirrors)
3113 struct list_head *head;
3114 struct btrfs_device *dev;
3115 struct btrfs_super_block *sb;
3116 struct btrfs_dev_item *dev_item;
3120 int total_errors = 0;
3123 max_errors = btrfs_super_num_devices(root->fs_info->super_copy) - 1;
3124 do_barriers = !btrfs_test_opt(root, NOBARRIER);
3125 backup_super_roots(root->fs_info);
3127 sb = root->fs_info->super_for_commit;
3128 dev_item = &sb->dev_item;
3130 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
3131 head = &root->fs_info->fs_devices->devices;
3134 ret = barrier_all_devices(root->fs_info);
3137 &root->fs_info->fs_devices->device_list_mutex);
3138 btrfs_error(root->fs_info, ret,
3139 "errors while submitting device barriers.");
3144 list_for_each_entry_rcu(dev, head, dev_list) {
3149 if (!dev->in_fs_metadata || !dev->writeable)
3152 btrfs_set_stack_device_generation(dev_item, 0);
3153 btrfs_set_stack_device_type(dev_item, dev->type);
3154 btrfs_set_stack_device_id(dev_item, dev->devid);
3155 btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes);
3156 btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used);
3157 btrfs_set_stack_device_io_align(dev_item, dev->io_align);
3158 btrfs_set_stack_device_io_width(dev_item, dev->io_width);
3159 btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
3160 memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
3161 memcpy(dev_item->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
3163 flags = btrfs_super_flags(sb);
3164 btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
3166 ret = write_dev_supers(dev, sb, do_barriers, 0, max_mirrors);
3170 if (total_errors > max_errors) {
3171 printk(KERN_ERR "btrfs: %d errors while writing supers\n",
3174 /* This shouldn't happen. FUA is masked off if unsupported */
3179 list_for_each_entry_rcu(dev, head, dev_list) {
3182 if (!dev->in_fs_metadata || !dev->writeable)
3185 ret = write_dev_supers(dev, sb, do_barriers, 1, max_mirrors);
3189 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
3190 if (total_errors > max_errors) {
3191 btrfs_error(root->fs_info, -EIO,
3192 "%d errors while writing supers", total_errors);
3198 int write_ctree_super(struct btrfs_trans_handle *trans,
3199 struct btrfs_root *root, int max_mirrors)
3203 ret = write_all_supers(root, max_mirrors);
3207 void btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
3209 spin_lock(&fs_info->fs_roots_radix_lock);
3210 radix_tree_delete(&fs_info->fs_roots_radix,
3211 (unsigned long)root->root_key.objectid);
3212 spin_unlock(&fs_info->fs_roots_radix_lock);
3214 if (btrfs_root_refs(&root->root_item) == 0)
3215 synchronize_srcu(&fs_info->subvol_srcu);
3217 __btrfs_remove_free_space_cache(root->free_ino_pinned);
3218 __btrfs_remove_free_space_cache(root->free_ino_ctl);
3222 static void free_fs_root(struct btrfs_root *root)
3224 iput(root->cache_inode);
3225 WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
3227 free_anon_bdev(root->anon_dev);
3228 free_extent_buffer(root->node);
3229 free_extent_buffer(root->commit_root);
3230 kfree(root->free_ino_ctl);
3231 kfree(root->free_ino_pinned);
3236 static void del_fs_roots(struct btrfs_fs_info *fs_info)
3239 struct btrfs_root *gang[8];
3242 while (!list_empty(&fs_info->dead_roots)) {
3243 gang[0] = list_entry(fs_info->dead_roots.next,
3244 struct btrfs_root, root_list);
3245 list_del(&gang[0]->root_list);
3247 if (gang[0]->in_radix) {
3248 btrfs_free_fs_root(fs_info, gang[0]);
3250 free_extent_buffer(gang[0]->node);
3251 free_extent_buffer(gang[0]->commit_root);
3257 ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
3262 for (i = 0; i < ret; i++)
3263 btrfs_free_fs_root(fs_info, gang[i]);
3267 int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
3269 u64 root_objectid = 0;
3270 struct btrfs_root *gang[8];
3275 ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
3276 (void **)gang, root_objectid,
3281 root_objectid = gang[ret - 1]->root_key.objectid + 1;
3282 for (i = 0; i < ret; i++) {
3285 root_objectid = gang[i]->root_key.objectid;
3286 err = btrfs_orphan_cleanup(gang[i]);
3295 int btrfs_commit_super(struct btrfs_root *root)
3297 struct btrfs_trans_handle *trans;
3300 mutex_lock(&root->fs_info->cleaner_mutex);
3301 btrfs_run_delayed_iputs(root);
3302 btrfs_clean_old_snapshots(root);
3303 mutex_unlock(&root->fs_info->cleaner_mutex);
3305 /* wait until ongoing cleanup work done */
3306 down_write(&root->fs_info->cleanup_work_sem);
3307 up_write(&root->fs_info->cleanup_work_sem);
3309 trans = btrfs_join_transaction(root);
3311 return PTR_ERR(trans);
3312 ret = btrfs_commit_transaction(trans, root);
3315 /* run commit again to drop the original snapshot */
3316 trans = btrfs_join_transaction(root);
3318 return PTR_ERR(trans);
3319 ret = btrfs_commit_transaction(trans, root);
3322 ret = btrfs_write_and_wait_transaction(NULL, root);
3324 btrfs_error(root->fs_info, ret,
3325 "Failed to sync btree inode to disk.");
3329 ret = write_ctree_super(NULL, root, 0);
3333 int close_ctree(struct btrfs_root *root)
3335 struct btrfs_fs_info *fs_info = root->fs_info;
3338 fs_info->closing = 1;
3341 /* pause restriper - we want to resume on mount */
3342 btrfs_pause_balance(fs_info);
3344 btrfs_dev_replace_suspend_for_unmount(fs_info);
3346 btrfs_scrub_cancel(fs_info);
3348 /* wait for any defraggers to finish */
3349 wait_event(fs_info->transaction_wait,
3350 (atomic_read(&fs_info->defrag_running) == 0));
3352 /* clear out the rbtree of defraggable inodes */
3353 btrfs_cleanup_defrag_inodes(fs_info);
3355 if (!(fs_info->sb->s_flags & MS_RDONLY)) {
3356 ret = btrfs_commit_super(root);
3358 printk(KERN_ERR "btrfs: commit super ret %d\n", ret);
3361 if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)
3362 btrfs_error_commit_super(root);
3364 btrfs_put_block_group_cache(fs_info);
3366 kthread_stop(fs_info->transaction_kthread);
3367 kthread_stop(fs_info->cleaner_kthread);
3369 fs_info->closing = 2;
3372 btrfs_free_qgroup_config(root->fs_info);
3374 if (percpu_counter_sum(&fs_info->delalloc_bytes)) {
3375 printk(KERN_INFO "btrfs: at unmount delalloc count %lld\n",
3376 percpu_counter_sum(&fs_info->delalloc_bytes));
3379 free_extent_buffer(fs_info->extent_root->node);
3380 free_extent_buffer(fs_info->extent_root->commit_root);
3381 free_extent_buffer(fs_info->tree_root->node);
3382 free_extent_buffer(fs_info->tree_root->commit_root);
3383 free_extent_buffer(fs_info->chunk_root->node);
3384 free_extent_buffer(fs_info->chunk_root->commit_root);
3385 free_extent_buffer(fs_info->dev_root->node);
3386 free_extent_buffer(fs_info->dev_root->commit_root);
3387 free_extent_buffer(fs_info->csum_root->node);
3388 free_extent_buffer(fs_info->csum_root->commit_root);
3389 if (fs_info->quota_root) {
3390 free_extent_buffer(fs_info->quota_root->node);
3391 free_extent_buffer(fs_info->quota_root->commit_root);
3394 btrfs_free_block_groups(fs_info);
3396 del_fs_roots(fs_info);
3398 iput(fs_info->btree_inode);
3400 btrfs_stop_workers(&fs_info->generic_worker);
3401 btrfs_stop_workers(&fs_info->fixup_workers);
3402 btrfs_stop_workers(&fs_info->delalloc_workers);
3403 btrfs_stop_workers(&fs_info->workers);
3404 btrfs_stop_workers(&fs_info->endio_workers);
3405 btrfs_stop_workers(&fs_info->endio_meta_workers);
3406 btrfs_stop_workers(&fs_info->endio_meta_write_workers);
3407 btrfs_stop_workers(&fs_info->endio_write_workers);
3408 btrfs_stop_workers(&fs_info->endio_freespace_worker);
3409 btrfs_stop_workers(&fs_info->submit_workers);
3410 btrfs_stop_workers(&fs_info->delayed_workers);
3411 btrfs_stop_workers(&fs_info->caching_workers);
3412 btrfs_stop_workers(&fs_info->readahead_workers);
3413 btrfs_stop_workers(&fs_info->flush_workers);
3415 #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
3416 if (btrfs_test_opt(root, CHECK_INTEGRITY))
3417 btrfsic_unmount(root, fs_info->fs_devices);
3420 btrfs_close_devices(fs_info->fs_devices);
3421 btrfs_mapping_tree_free(&fs_info->mapping_tree);
3423 percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
3424 percpu_counter_destroy(&fs_info->delalloc_bytes);
3425 bdi_destroy(&fs_info->bdi);
3426 cleanup_srcu_struct(&fs_info->subvol_srcu);
3431 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
3435 struct inode *btree_inode = buf->pages[0]->mapping->host;
3437 ret = extent_buffer_uptodate(buf);
3441 ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf,
3442 parent_transid, atomic);
3448 int btrfs_set_buffer_uptodate(struct extent_buffer *buf)
3450 return set_extent_buffer_uptodate(buf);
3453 void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
3455 struct btrfs_root *root = BTRFS_I(buf->pages[0]->mapping->host)->root;
3456 u64 transid = btrfs_header_generation(buf);
3459 btrfs_assert_tree_locked(buf);
3460 if (transid != root->fs_info->generation)
3461 WARN(1, KERN_CRIT "btrfs transid mismatch buffer %llu, "
3462 "found %llu running %llu\n",
3463 (unsigned long long)buf->start,
3464 (unsigned long long)transid,
3465 (unsigned long long)root->fs_info->generation);
3466 was_dirty = set_extent_buffer_dirty(buf);
3468 __percpu_counter_add(&root->fs_info->dirty_metadata_bytes,
3470 root->fs_info->dirty_metadata_batch);
3473 static void __btrfs_btree_balance_dirty(struct btrfs_root *root,
3477 * looks as though older kernels can get into trouble with
3478 * this code, they end up stuck in balance_dirty_pages forever
3482 if (current->flags & PF_MEMALLOC)
3486 btrfs_balance_delayed_items(root);
3488 ret = percpu_counter_compare(&root->fs_info->dirty_metadata_bytes,
3489 BTRFS_DIRTY_METADATA_THRESH);
3491 balance_dirty_pages_ratelimited_nr(
3492 root->fs_info->btree_inode->i_mapping, 1);
3497 void btrfs_btree_balance_dirty(struct btrfs_root *root)
3499 __btrfs_btree_balance_dirty(root, 1);
3502 void btrfs_btree_balance_dirty_nodelay(struct btrfs_root *root)
3504 __btrfs_btree_balance_dirty(root, 0);
3507 int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid)
3509 struct btrfs_root *root = BTRFS_I(buf->pages[0]->mapping->host)->root;
3510 return btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
3513 static int btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
3516 if (btrfs_super_csum_type(fs_info->super_copy) >= ARRAY_SIZE(btrfs_csum_sizes)) {
3517 printk(KERN_ERR "btrfs: unsupported checksum algorithm\n");
3527 void btrfs_error_commit_super(struct btrfs_root *root)
3529 mutex_lock(&root->fs_info->cleaner_mutex);
3530 btrfs_run_delayed_iputs(root);
3531 mutex_unlock(&root->fs_info->cleaner_mutex);
3533 down_write(&root->fs_info->cleanup_work_sem);
3534 up_write(&root->fs_info->cleanup_work_sem);
3536 /* cleanup FS via transaction */
3537 btrfs_cleanup_transaction(root);
3540 static void btrfs_destroy_ordered_operations(struct btrfs_root *root)
3542 struct btrfs_inode *btrfs_inode;
3543 struct list_head splice;
3545 INIT_LIST_HEAD(&splice);
3547 mutex_lock(&root->fs_info->ordered_operations_mutex);
3548 spin_lock(&root->fs_info->ordered_extent_lock);
3550 list_splice_init(&root->fs_info->ordered_operations, &splice);
3551 while (!list_empty(&splice)) {
3552 btrfs_inode = list_entry(splice.next, struct btrfs_inode,
3553 ordered_operations);
3555 list_del_init(&btrfs_inode->ordered_operations);
3557 btrfs_invalidate_inodes(btrfs_inode->root);
3560 spin_unlock(&root->fs_info->ordered_extent_lock);
3561 mutex_unlock(&root->fs_info->ordered_operations_mutex);
3564 static void btrfs_destroy_ordered_extents(struct btrfs_root *root)
3566 struct list_head splice;
3567 struct btrfs_ordered_extent *ordered;
3568 struct inode *inode;
3570 INIT_LIST_HEAD(&splice);
3572 spin_lock(&root->fs_info->ordered_extent_lock);
3574 list_splice_init(&root->fs_info->ordered_extents, &splice);
3575 while (!list_empty(&splice)) {
3576 ordered = list_entry(splice.next, struct btrfs_ordered_extent,
3579 list_del_init(&ordered->root_extent_list);
3580 atomic_inc(&ordered->refs);
3582 /* the inode may be getting freed (in sys_unlink path). */
3583 inode = igrab(ordered->inode);
3585 spin_unlock(&root->fs_info->ordered_extent_lock);
3589 atomic_set(&ordered->refs, 1);
3590 btrfs_put_ordered_extent(ordered);
3592 spin_lock(&root->fs_info->ordered_extent_lock);
3595 spin_unlock(&root->fs_info->ordered_extent_lock);
3598 int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
3599 struct btrfs_root *root)
3601 struct rb_node *node;
3602 struct btrfs_delayed_ref_root *delayed_refs;
3603 struct btrfs_delayed_ref_node *ref;
3606 delayed_refs = &trans->delayed_refs;
3608 spin_lock(&delayed_refs->lock);
3609 if (delayed_refs->num_entries == 0) {
3610 spin_unlock(&delayed_refs->lock);
3611 printk(KERN_INFO "delayed_refs has NO entry\n");
3615 while ((node = rb_first(&delayed_refs->root)) != NULL) {
3616 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
3618 atomic_set(&ref->refs, 1);
3619 if (btrfs_delayed_ref_is_head(ref)) {
3620 struct btrfs_delayed_ref_head *head;
3622 head = btrfs_delayed_node_to_head(ref);
3623 if (!mutex_trylock(&head->mutex)) {
3624 atomic_inc(&ref->refs);
3625 spin_unlock(&delayed_refs->lock);
3627 /* Need to wait for the delayed ref to run */
3628 mutex_lock(&head->mutex);
3629 mutex_unlock(&head->mutex);
3630 btrfs_put_delayed_ref(ref);
3632 spin_lock(&delayed_refs->lock);
3636 btrfs_free_delayed_extent_op(head->extent_op);
3637 delayed_refs->num_heads--;
3638 if (list_empty(&head->cluster))
3639 delayed_refs->num_heads_ready--;
3640 list_del_init(&head->cluster);
3643 rb_erase(&ref->rb_node, &delayed_refs->root);
3644 delayed_refs->num_entries--;
3646 spin_unlock(&delayed_refs->lock);
3647 btrfs_put_delayed_ref(ref);
3650 spin_lock(&delayed_refs->lock);
3653 spin_unlock(&delayed_refs->lock);
3658 static void btrfs_destroy_pending_snapshots(struct btrfs_transaction *t)
3660 struct btrfs_pending_snapshot *snapshot;
3661 struct list_head splice;
3663 INIT_LIST_HEAD(&splice);
3665 list_splice_init(&t->pending_snapshots, &splice);
3667 while (!list_empty(&splice)) {
3668 snapshot = list_entry(splice.next,
3669 struct btrfs_pending_snapshot,
3672 list_del_init(&snapshot->list);
3678 static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
3680 struct btrfs_inode *btrfs_inode;
3681 struct list_head splice;
3683 INIT_LIST_HEAD(&splice);
3685 spin_lock(&root->fs_info->delalloc_lock);
3686 list_splice_init(&root->fs_info->delalloc_inodes, &splice);
3688 while (!list_empty(&splice)) {
3689 btrfs_inode = list_entry(splice.next, struct btrfs_inode,
3692 list_del_init(&btrfs_inode->delalloc_inodes);
3694 btrfs_invalidate_inodes(btrfs_inode->root);
3697 spin_unlock(&root->fs_info->delalloc_lock);
3700 static int btrfs_destroy_marked_extents(struct btrfs_root *root,
3701 struct extent_io_tree *dirty_pages,
3706 struct inode *btree_inode = root->fs_info->btree_inode;
3707 struct extent_buffer *eb;
3711 unsigned long index;
3714 ret = find_first_extent_bit(dirty_pages, start, &start, &end,
3719 clear_extent_bits(dirty_pages, start, end, mark, GFP_NOFS);
3720 while (start <= end) {
3721 index = start >> PAGE_CACHE_SHIFT;
3722 start = (u64)(index + 1) << PAGE_CACHE_SHIFT;
3723 page = find_get_page(btree_inode->i_mapping, index);
3726 offset = page_offset(page);
3728 spin_lock(&dirty_pages->buffer_lock);
3729 eb = radix_tree_lookup(
3730 &(&BTRFS_I(page->mapping->host)->io_tree)->buffer,
3731 offset >> PAGE_CACHE_SHIFT);
3732 spin_unlock(&dirty_pages->buffer_lock);
3734 ret = test_and_clear_bit(EXTENT_BUFFER_DIRTY,
3736 if (PageWriteback(page))
3737 end_page_writeback(page);
3740 if (PageDirty(page)) {
3741 clear_page_dirty_for_io(page);
3742 spin_lock_irq(&page->mapping->tree_lock);
3743 radix_tree_tag_clear(&page->mapping->page_tree,
3745 PAGECACHE_TAG_DIRTY);
3746 spin_unlock_irq(&page->mapping->tree_lock);
3750 page_cache_release(page);
3757 static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
3758 struct extent_io_tree *pinned_extents)
3760 struct extent_io_tree *unpin;
3766 unpin = pinned_extents;
3769 ret = find_first_extent_bit(unpin, 0, &start, &end,
3770 EXTENT_DIRTY, NULL);
3775 if (btrfs_test_opt(root, DISCARD))
3776 ret = btrfs_error_discard_extent(root, start,
3780 clear_extent_dirty(unpin, start, end, GFP_NOFS);
3781 btrfs_error_unpin_extent_range(root, start, end);
3786 if (unpin == &root->fs_info->freed_extents[0])
3787 unpin = &root->fs_info->freed_extents[1];
3789 unpin = &root->fs_info->freed_extents[0];
3797 void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
3798 struct btrfs_root *root)
3800 btrfs_destroy_delayed_refs(cur_trans, root);
3801 btrfs_block_rsv_release(root, &root->fs_info->trans_block_rsv,
3802 cur_trans->dirty_pages.dirty_bytes);
3804 /* FIXME: cleanup wait for commit */
3805 cur_trans->in_commit = 1;
3806 cur_trans->blocked = 1;
3807 wake_up(&root->fs_info->transaction_blocked_wait);
3809 cur_trans->blocked = 0;
3810 wake_up(&root->fs_info->transaction_wait);
3812 cur_trans->commit_done = 1;
3813 wake_up(&cur_trans->commit_wait);
3815 btrfs_destroy_delayed_inodes(root);
3816 btrfs_assert_delayed_root_empty(root);
3818 btrfs_destroy_pending_snapshots(cur_trans);
3820 btrfs_destroy_marked_extents(root, &cur_trans->dirty_pages,
3822 btrfs_destroy_pinned_extent(root,
3823 root->fs_info->pinned_extents);
3826 memset(cur_trans, 0, sizeof(*cur_trans));
3827 kmem_cache_free(btrfs_transaction_cachep, cur_trans);
3831 int btrfs_cleanup_transaction(struct btrfs_root *root)
3833 struct btrfs_transaction *t;
3836 mutex_lock(&root->fs_info->transaction_kthread_mutex);
3838 spin_lock(&root->fs_info->trans_lock);
3839 list_splice_init(&root->fs_info->trans_list, &list);
3840 root->fs_info->trans_no_join = 1;
3841 spin_unlock(&root->fs_info->trans_lock);
3843 while (!list_empty(&list)) {
3844 t = list_entry(list.next, struct btrfs_transaction, list);
3848 btrfs_destroy_ordered_operations(root);
3850 btrfs_destroy_ordered_extents(root);
3852 btrfs_destroy_delayed_refs(t, root);
3854 btrfs_block_rsv_release(root,
3855 &root->fs_info->trans_block_rsv,
3856 t->dirty_pages.dirty_bytes);
3858 /* FIXME: cleanup wait for commit */
3862 if (waitqueue_active(&root->fs_info->transaction_blocked_wait))
3863 wake_up(&root->fs_info->transaction_blocked_wait);
3867 if (waitqueue_active(&root->fs_info->transaction_wait))
3868 wake_up(&root->fs_info->transaction_wait);
3872 if (waitqueue_active(&t->commit_wait))
3873 wake_up(&t->commit_wait);
3875 btrfs_destroy_delayed_inodes(root);
3876 btrfs_assert_delayed_root_empty(root);
3878 btrfs_destroy_pending_snapshots(t);
3880 btrfs_destroy_delalloc_inodes(root);
3882 spin_lock(&root->fs_info->trans_lock);
3883 root->fs_info->running_transaction = NULL;
3884 spin_unlock(&root->fs_info->trans_lock);
3886 btrfs_destroy_marked_extents(root, &t->dirty_pages,
3889 btrfs_destroy_pinned_extent(root,
3890 root->fs_info->pinned_extents);
3892 atomic_set(&t->use_count, 0);
3893 list_del_init(&t->list);
3894 memset(t, 0, sizeof(*t));
3895 kmem_cache_free(btrfs_transaction_cachep, t);
3898 spin_lock(&root->fs_info->trans_lock);
3899 root->fs_info->trans_no_join = 0;
3900 spin_unlock(&root->fs_info->trans_lock);
3901 mutex_unlock(&root->fs_info->transaction_kthread_mutex);
3906 static struct extent_io_ops btree_extent_io_ops = {
3907 .readpage_end_io_hook = btree_readpage_end_io_hook,
3908 .readpage_io_failed_hook = btree_io_failed_hook,
3909 .submit_bio_hook = btree_submit_bio_hook,
3910 /* note we're sharing with inode.c for the merge bio hook */
3911 .merge_bio_hook = btrfs_merge_bio_hook,