1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (C) 2007 Oracle. All rights reserved.
6 #include <linux/sched.h>
7 #include <linux/sched/signal.h>
8 #include <linux/pagemap.h>
9 #include <linux/writeback.h>
10 #include <linux/blkdev.h>
11 #include <linux/sort.h>
12 #include <linux/rcupdate.h>
13 #include <linux/kthread.h>
14 #include <linux/slab.h>
15 #include <linux/ratelimit.h>
16 #include <linux/percpu_counter.h>
17 #include <linux/lockdep.h>
18 #include <linux/crc32c.h>
21 #include "print-tree.h"
25 #include "free-space-cache.h"
26 #include "free-space-tree.h"
30 #include "ref-verify.h"
32 #undef SCRAMBLE_DELAYED_REFS
35 * control flags for do_chunk_alloc's force field
36 * CHUNK_ALLOC_NO_FORCE means to only allocate a chunk
37 * if we really need one.
39 * CHUNK_ALLOC_LIMITED means to only try and allocate one
40 * if we have very few chunks already allocated. This is
41 * used as part of the clustering code to help make sure
42 * we have a good pool of storage to cluster in, without
43 * filling the FS with empty chunks
45 * CHUNK_ALLOC_FORCE means it must try to allocate one
49 CHUNK_ALLOC_NO_FORCE = 0,
50 CHUNK_ALLOC_LIMITED = 1,
51 CHUNK_ALLOC_FORCE = 2,
55 * Declare a helper function to detect underflow of various space info members
57 #define DECLARE_SPACE_INFO_UPDATE(name) \
58 static inline void update_##name(struct btrfs_space_info *sinfo, \
61 if (bytes < 0 && sinfo->name < -bytes) { \
66 sinfo->name += bytes; \
69 DECLARE_SPACE_INFO_UPDATE(bytes_may_use);
70 DECLARE_SPACE_INFO_UPDATE(bytes_pinned);
72 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
73 struct btrfs_delayed_ref_node *node, u64 parent,
74 u64 root_objectid, u64 owner_objectid,
75 u64 owner_offset, int refs_to_drop,
76 struct btrfs_delayed_extent_op *extra_op);
77 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
78 struct extent_buffer *leaf,
79 struct btrfs_extent_item *ei);
80 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
81 u64 parent, u64 root_objectid,
82 u64 flags, u64 owner, u64 offset,
83 struct btrfs_key *ins, int ref_mod);
84 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
85 struct btrfs_delayed_ref_node *node,
86 struct btrfs_delayed_extent_op *extent_op);
87 static int do_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
89 static int find_next_key(struct btrfs_path *path, int level,
90 struct btrfs_key *key);
91 static void dump_space_info(struct btrfs_fs_info *fs_info,
92 struct btrfs_space_info *info, u64 bytes,
93 int dump_block_groups);
94 static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
96 static void space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
97 struct btrfs_space_info *space_info,
99 static void space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
100 struct btrfs_space_info *space_info,
104 block_group_cache_done(struct btrfs_block_group_cache *cache)
107 return cache->cached == BTRFS_CACHE_FINISHED ||
108 cache->cached == BTRFS_CACHE_ERROR;
111 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
113 return (cache->flags & bits) == bits;
116 void btrfs_get_block_group(struct btrfs_block_group_cache *cache)
118 atomic_inc(&cache->count);
121 void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
123 if (atomic_dec_and_test(&cache->count)) {
124 WARN_ON(cache->pinned > 0);
125 WARN_ON(cache->reserved > 0);
128 * If not empty, someone is still holding mutex of
129 * full_stripe_lock, which can only be released by caller.
130 * And it will definitely cause use-after-free when caller
131 * tries to release full stripe lock.
133 * No better way to resolve, but only to warn.
135 WARN_ON(!RB_EMPTY_ROOT(&cache->full_stripe_locks_root.root));
136 kfree(cache->free_space_ctl);
142 * this adds the block group to the fs_info rb tree for the block group
145 static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
146 struct btrfs_block_group_cache *block_group)
149 struct rb_node *parent = NULL;
150 struct btrfs_block_group_cache *cache;
152 spin_lock(&info->block_group_cache_lock);
153 p = &info->block_group_cache_tree.rb_node;
157 cache = rb_entry(parent, struct btrfs_block_group_cache,
159 if (block_group->key.objectid < cache->key.objectid) {
161 } else if (block_group->key.objectid > cache->key.objectid) {
164 spin_unlock(&info->block_group_cache_lock);
169 rb_link_node(&block_group->cache_node, parent, p);
170 rb_insert_color(&block_group->cache_node,
171 &info->block_group_cache_tree);
173 if (info->first_logical_byte > block_group->key.objectid)
174 info->first_logical_byte = block_group->key.objectid;
176 spin_unlock(&info->block_group_cache_lock);
182 * This will return the block group at or after bytenr if contains is 0, else
183 * it will return the block group that contains the bytenr
185 static struct btrfs_block_group_cache *
186 block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
189 struct btrfs_block_group_cache *cache, *ret = NULL;
193 spin_lock(&info->block_group_cache_lock);
194 n = info->block_group_cache_tree.rb_node;
197 cache = rb_entry(n, struct btrfs_block_group_cache,
199 end = cache->key.objectid + cache->key.offset - 1;
200 start = cache->key.objectid;
202 if (bytenr < start) {
203 if (!contains && (!ret || start < ret->key.objectid))
206 } else if (bytenr > start) {
207 if (contains && bytenr <= end) {
218 btrfs_get_block_group(ret);
219 if (bytenr == 0 && info->first_logical_byte > ret->key.objectid)
220 info->first_logical_byte = ret->key.objectid;
222 spin_unlock(&info->block_group_cache_lock);
227 static int add_excluded_extent(struct btrfs_fs_info *fs_info,
228 u64 start, u64 num_bytes)
230 u64 end = start + num_bytes - 1;
231 set_extent_bits(&fs_info->freed_extents[0],
232 start, end, EXTENT_UPTODATE);
233 set_extent_bits(&fs_info->freed_extents[1],
234 start, end, EXTENT_UPTODATE);
238 static void free_excluded_extents(struct btrfs_block_group_cache *cache)
240 struct btrfs_fs_info *fs_info = cache->fs_info;
243 start = cache->key.objectid;
244 end = start + cache->key.offset - 1;
246 clear_extent_bits(&fs_info->freed_extents[0],
247 start, end, EXTENT_UPTODATE);
248 clear_extent_bits(&fs_info->freed_extents[1],
249 start, end, EXTENT_UPTODATE);
252 static int exclude_super_stripes(struct btrfs_block_group_cache *cache)
254 struct btrfs_fs_info *fs_info = cache->fs_info;
260 if (cache->key.objectid < BTRFS_SUPER_INFO_OFFSET) {
261 stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->key.objectid;
262 cache->bytes_super += stripe_len;
263 ret = add_excluded_extent(fs_info, cache->key.objectid,
269 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
270 bytenr = btrfs_sb_offset(i);
271 ret = btrfs_rmap_block(fs_info, cache->key.objectid,
272 bytenr, &logical, &nr, &stripe_len);
279 if (logical[nr] > cache->key.objectid +
283 if (logical[nr] + stripe_len <= cache->key.objectid)
287 if (start < cache->key.objectid) {
288 start = cache->key.objectid;
289 len = (logical[nr] + stripe_len) - start;
291 len = min_t(u64, stripe_len,
292 cache->key.objectid +
293 cache->key.offset - start);
296 cache->bytes_super += len;
297 ret = add_excluded_extent(fs_info, start, len);
309 static struct btrfs_caching_control *
310 get_caching_control(struct btrfs_block_group_cache *cache)
312 struct btrfs_caching_control *ctl;
314 spin_lock(&cache->lock);
315 if (!cache->caching_ctl) {
316 spin_unlock(&cache->lock);
320 ctl = cache->caching_ctl;
321 refcount_inc(&ctl->count);
322 spin_unlock(&cache->lock);
326 static void put_caching_control(struct btrfs_caching_control *ctl)
328 if (refcount_dec_and_test(&ctl->count))
332 #ifdef CONFIG_BTRFS_DEBUG
333 static void fragment_free_space(struct btrfs_block_group_cache *block_group)
335 struct btrfs_fs_info *fs_info = block_group->fs_info;
336 u64 start = block_group->key.objectid;
337 u64 len = block_group->key.offset;
338 u64 chunk = block_group->flags & BTRFS_BLOCK_GROUP_METADATA ?
339 fs_info->nodesize : fs_info->sectorsize;
340 u64 step = chunk << 1;
342 while (len > chunk) {
343 btrfs_remove_free_space(block_group, start, chunk);
354 * this is only called by cache_block_group, since we could have freed extents
355 * we need to check the pinned_extents for any extents that can't be used yet
356 * since their free space will be released as soon as the transaction commits.
358 u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
361 struct btrfs_fs_info *info = block_group->fs_info;
362 u64 extent_start, extent_end, size, total_added = 0;
365 while (start < end) {
366 ret = find_first_extent_bit(info->pinned_extents, start,
367 &extent_start, &extent_end,
368 EXTENT_DIRTY | EXTENT_UPTODATE,
373 if (extent_start <= start) {
374 start = extent_end + 1;
375 } else if (extent_start > start && extent_start < end) {
376 size = extent_start - start;
378 ret = btrfs_add_free_space(block_group, start,
380 BUG_ON(ret); /* -ENOMEM or logic error */
381 start = extent_end + 1;
390 ret = btrfs_add_free_space(block_group, start, size);
391 BUG_ON(ret); /* -ENOMEM or logic error */
397 static int load_extent_tree_free(struct btrfs_caching_control *caching_ctl)
399 struct btrfs_block_group_cache *block_group = caching_ctl->block_group;
400 struct btrfs_fs_info *fs_info = block_group->fs_info;
401 struct btrfs_root *extent_root = fs_info->extent_root;
402 struct btrfs_path *path;
403 struct extent_buffer *leaf;
404 struct btrfs_key key;
411 path = btrfs_alloc_path();
415 last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
417 #ifdef CONFIG_BTRFS_DEBUG
419 * If we're fragmenting we don't want to make anybody think we can
420 * allocate from this block group until we've had a chance to fragment
423 if (btrfs_should_fragment_free_space(block_group))
427 * We don't want to deadlock with somebody trying to allocate a new
428 * extent for the extent root while also trying to search the extent
429 * root to add free space. So we skip locking and search the commit
430 * root, since its read-only
432 path->skip_locking = 1;
433 path->search_commit_root = 1;
434 path->reada = READA_FORWARD;
438 key.type = BTRFS_EXTENT_ITEM_KEY;
441 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
445 leaf = path->nodes[0];
446 nritems = btrfs_header_nritems(leaf);
449 if (btrfs_fs_closing(fs_info) > 1) {
454 if (path->slots[0] < nritems) {
455 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
457 ret = find_next_key(path, 0, &key);
461 if (need_resched() ||
462 rwsem_is_contended(&fs_info->commit_root_sem)) {
464 caching_ctl->progress = last;
465 btrfs_release_path(path);
466 up_read(&fs_info->commit_root_sem);
467 mutex_unlock(&caching_ctl->mutex);
469 mutex_lock(&caching_ctl->mutex);
470 down_read(&fs_info->commit_root_sem);
474 ret = btrfs_next_leaf(extent_root, path);
479 leaf = path->nodes[0];
480 nritems = btrfs_header_nritems(leaf);
484 if (key.objectid < last) {
487 key.type = BTRFS_EXTENT_ITEM_KEY;
490 caching_ctl->progress = last;
491 btrfs_release_path(path);
495 if (key.objectid < block_group->key.objectid) {
500 if (key.objectid >= block_group->key.objectid +
501 block_group->key.offset)
504 if (key.type == BTRFS_EXTENT_ITEM_KEY ||
505 key.type == BTRFS_METADATA_ITEM_KEY) {
506 total_found += add_new_free_space(block_group, last,
508 if (key.type == BTRFS_METADATA_ITEM_KEY)
509 last = key.objectid +
512 last = key.objectid + key.offset;
514 if (total_found > CACHING_CTL_WAKE_UP) {
517 wake_up(&caching_ctl->wait);
524 total_found += add_new_free_space(block_group, last,
525 block_group->key.objectid +
526 block_group->key.offset);
527 caching_ctl->progress = (u64)-1;
530 btrfs_free_path(path);
534 static noinline void caching_thread(struct btrfs_work *work)
536 struct btrfs_block_group_cache *block_group;
537 struct btrfs_fs_info *fs_info;
538 struct btrfs_caching_control *caching_ctl;
541 caching_ctl = container_of(work, struct btrfs_caching_control, work);
542 block_group = caching_ctl->block_group;
543 fs_info = block_group->fs_info;
545 mutex_lock(&caching_ctl->mutex);
546 down_read(&fs_info->commit_root_sem);
548 if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE))
549 ret = load_free_space_tree(caching_ctl);
551 ret = load_extent_tree_free(caching_ctl);
553 spin_lock(&block_group->lock);
554 block_group->caching_ctl = NULL;
555 block_group->cached = ret ? BTRFS_CACHE_ERROR : BTRFS_CACHE_FINISHED;
556 spin_unlock(&block_group->lock);
558 #ifdef CONFIG_BTRFS_DEBUG
559 if (btrfs_should_fragment_free_space(block_group)) {
562 spin_lock(&block_group->space_info->lock);
563 spin_lock(&block_group->lock);
564 bytes_used = block_group->key.offset -
565 btrfs_block_group_used(&block_group->item);
566 block_group->space_info->bytes_used += bytes_used >> 1;
567 spin_unlock(&block_group->lock);
568 spin_unlock(&block_group->space_info->lock);
569 fragment_free_space(block_group);
573 caching_ctl->progress = (u64)-1;
575 up_read(&fs_info->commit_root_sem);
576 free_excluded_extents(block_group);
577 mutex_unlock(&caching_ctl->mutex);
579 wake_up(&caching_ctl->wait);
581 put_caching_control(caching_ctl);
582 btrfs_put_block_group(block_group);
585 static int cache_block_group(struct btrfs_block_group_cache *cache,
589 struct btrfs_fs_info *fs_info = cache->fs_info;
590 struct btrfs_caching_control *caching_ctl;
593 caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_NOFS);
597 INIT_LIST_HEAD(&caching_ctl->list);
598 mutex_init(&caching_ctl->mutex);
599 init_waitqueue_head(&caching_ctl->wait);
600 caching_ctl->block_group = cache;
601 caching_ctl->progress = cache->key.objectid;
602 refcount_set(&caching_ctl->count, 1);
603 btrfs_init_work(&caching_ctl->work, btrfs_cache_helper,
604 caching_thread, NULL, NULL);
606 spin_lock(&cache->lock);
608 * This should be a rare occasion, but this could happen I think in the
609 * case where one thread starts to load the space cache info, and then
610 * some other thread starts a transaction commit which tries to do an
611 * allocation while the other thread is still loading the space cache
612 * info. The previous loop should have kept us from choosing this block
613 * group, but if we've moved to the state where we will wait on caching
614 * block groups we need to first check if we're doing a fast load here,
615 * so we can wait for it to finish, otherwise we could end up allocating
616 * from a block group who's cache gets evicted for one reason or
619 while (cache->cached == BTRFS_CACHE_FAST) {
620 struct btrfs_caching_control *ctl;
622 ctl = cache->caching_ctl;
623 refcount_inc(&ctl->count);
624 prepare_to_wait(&ctl->wait, &wait, TASK_UNINTERRUPTIBLE);
625 spin_unlock(&cache->lock);
629 finish_wait(&ctl->wait, &wait);
630 put_caching_control(ctl);
631 spin_lock(&cache->lock);
634 if (cache->cached != BTRFS_CACHE_NO) {
635 spin_unlock(&cache->lock);
639 WARN_ON(cache->caching_ctl);
640 cache->caching_ctl = caching_ctl;
641 cache->cached = BTRFS_CACHE_FAST;
642 spin_unlock(&cache->lock);
644 if (btrfs_test_opt(fs_info, SPACE_CACHE)) {
645 mutex_lock(&caching_ctl->mutex);
646 ret = load_free_space_cache(cache);
648 spin_lock(&cache->lock);
650 cache->caching_ctl = NULL;
651 cache->cached = BTRFS_CACHE_FINISHED;
652 cache->last_byte_to_unpin = (u64)-1;
653 caching_ctl->progress = (u64)-1;
655 if (load_cache_only) {
656 cache->caching_ctl = NULL;
657 cache->cached = BTRFS_CACHE_NO;
659 cache->cached = BTRFS_CACHE_STARTED;
660 cache->has_caching_ctl = 1;
663 spin_unlock(&cache->lock);
664 #ifdef CONFIG_BTRFS_DEBUG
666 btrfs_should_fragment_free_space(cache)) {
669 spin_lock(&cache->space_info->lock);
670 spin_lock(&cache->lock);
671 bytes_used = cache->key.offset -
672 btrfs_block_group_used(&cache->item);
673 cache->space_info->bytes_used += bytes_used >> 1;
674 spin_unlock(&cache->lock);
675 spin_unlock(&cache->space_info->lock);
676 fragment_free_space(cache);
679 mutex_unlock(&caching_ctl->mutex);
681 wake_up(&caching_ctl->wait);
683 put_caching_control(caching_ctl);
684 free_excluded_extents(cache);
689 * We're either using the free space tree or no caching at all.
690 * Set cached to the appropriate value and wakeup any waiters.
692 spin_lock(&cache->lock);
693 if (load_cache_only) {
694 cache->caching_ctl = NULL;
695 cache->cached = BTRFS_CACHE_NO;
697 cache->cached = BTRFS_CACHE_STARTED;
698 cache->has_caching_ctl = 1;
700 spin_unlock(&cache->lock);
701 wake_up(&caching_ctl->wait);
704 if (load_cache_only) {
705 put_caching_control(caching_ctl);
709 down_write(&fs_info->commit_root_sem);
710 refcount_inc(&caching_ctl->count);
711 list_add_tail(&caching_ctl->list, &fs_info->caching_block_groups);
712 up_write(&fs_info->commit_root_sem);
714 btrfs_get_block_group(cache);
716 btrfs_queue_work(fs_info->caching_workers, &caching_ctl->work);
722 * return the block group that starts at or after bytenr
724 static struct btrfs_block_group_cache *
725 btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr)
727 return block_group_cache_tree_search(info, bytenr, 0);
731 * return the block group that contains the given bytenr
733 struct btrfs_block_group_cache *btrfs_lookup_block_group(
734 struct btrfs_fs_info *info,
737 return block_group_cache_tree_search(info, bytenr, 1);
740 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
743 struct list_head *head = &info->space_info;
744 struct btrfs_space_info *found;
746 flags &= BTRFS_BLOCK_GROUP_TYPE_MASK;
749 list_for_each_entry_rcu(found, head, list) {
750 if (found->flags & flags) {
759 static void add_pinned_bytes(struct btrfs_fs_info *fs_info,
760 struct btrfs_ref *ref, int sign)
762 struct btrfs_space_info *space_info;
766 ASSERT(sign == 1 || sign == -1);
767 num_bytes = sign * ref->len;
768 if (ref->type == BTRFS_REF_METADATA) {
769 if (ref->tree_ref.root == BTRFS_CHUNK_TREE_OBJECTID)
770 flags = BTRFS_BLOCK_GROUP_SYSTEM;
772 flags = BTRFS_BLOCK_GROUP_METADATA;
774 flags = BTRFS_BLOCK_GROUP_DATA;
777 space_info = __find_space_info(fs_info, flags);
779 percpu_counter_add_batch(&space_info->total_bytes_pinned, num_bytes,
780 BTRFS_TOTAL_BYTES_PINNED_BATCH);
784 * after adding space to the filesystem, we need to clear the full flags
785 * on all the space infos.
787 void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
789 struct list_head *head = &info->space_info;
790 struct btrfs_space_info *found;
793 list_for_each_entry_rcu(found, head, list)
798 /* simple helper to search for an existing data extent at a given offset */
799 int btrfs_lookup_data_extent(struct btrfs_fs_info *fs_info, u64 start, u64 len)
802 struct btrfs_key key;
803 struct btrfs_path *path;
805 path = btrfs_alloc_path();
809 key.objectid = start;
811 key.type = BTRFS_EXTENT_ITEM_KEY;
812 ret = btrfs_search_slot(NULL, fs_info->extent_root, &key, path, 0, 0);
813 btrfs_free_path(path);
818 * helper function to lookup reference count and flags of a tree block.
820 * the head node for delayed ref is used to store the sum of all the
821 * reference count modifications queued up in the rbtree. the head
822 * node may also store the extent flags to set. This way you can check
823 * to see what the reference count and extent flags would be if all of
824 * the delayed refs are not processed.
826 int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
827 struct btrfs_fs_info *fs_info, u64 bytenr,
828 u64 offset, int metadata, u64 *refs, u64 *flags)
830 struct btrfs_delayed_ref_head *head;
831 struct btrfs_delayed_ref_root *delayed_refs;
832 struct btrfs_path *path;
833 struct btrfs_extent_item *ei;
834 struct extent_buffer *leaf;
835 struct btrfs_key key;
842 * If we don't have skinny metadata, don't bother doing anything
845 if (metadata && !btrfs_fs_incompat(fs_info, SKINNY_METADATA)) {
846 offset = fs_info->nodesize;
850 path = btrfs_alloc_path();
855 path->skip_locking = 1;
856 path->search_commit_root = 1;
860 key.objectid = bytenr;
863 key.type = BTRFS_METADATA_ITEM_KEY;
865 key.type = BTRFS_EXTENT_ITEM_KEY;
867 ret = btrfs_search_slot(trans, fs_info->extent_root, &key, path, 0, 0);
871 if (ret > 0 && metadata && key.type == BTRFS_METADATA_ITEM_KEY) {
872 if (path->slots[0]) {
874 btrfs_item_key_to_cpu(path->nodes[0], &key,
876 if (key.objectid == bytenr &&
877 key.type == BTRFS_EXTENT_ITEM_KEY &&
878 key.offset == fs_info->nodesize)
884 leaf = path->nodes[0];
885 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
886 if (item_size >= sizeof(*ei)) {
887 ei = btrfs_item_ptr(leaf, path->slots[0],
888 struct btrfs_extent_item);
889 num_refs = btrfs_extent_refs(leaf, ei);
890 extent_flags = btrfs_extent_flags(leaf, ei);
893 btrfs_print_v0_err(fs_info);
895 btrfs_abort_transaction(trans, ret);
897 btrfs_handle_fs_error(fs_info, ret, NULL);
902 BUG_ON(num_refs == 0);
912 delayed_refs = &trans->transaction->delayed_refs;
913 spin_lock(&delayed_refs->lock);
914 head = btrfs_find_delayed_ref_head(delayed_refs, bytenr);
916 if (!mutex_trylock(&head->mutex)) {
917 refcount_inc(&head->refs);
918 spin_unlock(&delayed_refs->lock);
920 btrfs_release_path(path);
923 * Mutex was contended, block until it's released and try
926 mutex_lock(&head->mutex);
927 mutex_unlock(&head->mutex);
928 btrfs_put_delayed_ref_head(head);
931 spin_lock(&head->lock);
932 if (head->extent_op && head->extent_op->update_flags)
933 extent_flags |= head->extent_op->flags_to_set;
935 BUG_ON(num_refs == 0);
937 num_refs += head->ref_mod;
938 spin_unlock(&head->lock);
939 mutex_unlock(&head->mutex);
941 spin_unlock(&delayed_refs->lock);
943 WARN_ON(num_refs == 0);
947 *flags = extent_flags;
949 btrfs_free_path(path);
954 * Back reference rules. Back refs have three main goals:
956 * 1) differentiate between all holders of references to an extent so that
957 * when a reference is dropped we can make sure it was a valid reference
958 * before freeing the extent.
960 * 2) Provide enough information to quickly find the holders of an extent
961 * if we notice a given block is corrupted or bad.
963 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
964 * maintenance. This is actually the same as #2, but with a slightly
965 * different use case.
967 * There are two kinds of back refs. The implicit back refs is optimized
968 * for pointers in non-shared tree blocks. For a given pointer in a block,
969 * back refs of this kind provide information about the block's owner tree
970 * and the pointer's key. These information allow us to find the block by
971 * b-tree searching. The full back refs is for pointers in tree blocks not
972 * referenced by their owner trees. The location of tree block is recorded
973 * in the back refs. Actually the full back refs is generic, and can be
974 * used in all cases the implicit back refs is used. The major shortcoming
975 * of the full back refs is its overhead. Every time a tree block gets
976 * COWed, we have to update back refs entry for all pointers in it.
978 * For a newly allocated tree block, we use implicit back refs for
979 * pointers in it. This means most tree related operations only involve
980 * implicit back refs. For a tree block created in old transaction, the
981 * only way to drop a reference to it is COW it. So we can detect the
982 * event that tree block loses its owner tree's reference and do the
983 * back refs conversion.
985 * When a tree block is COWed through a tree, there are four cases:
987 * The reference count of the block is one and the tree is the block's
988 * owner tree. Nothing to do in this case.
990 * The reference count of the block is one and the tree is not the
991 * block's owner tree. In this case, full back refs is used for pointers
992 * in the block. Remove these full back refs, add implicit back refs for
993 * every pointers in the new block.
995 * The reference count of the block is greater than one and the tree is
996 * the block's owner tree. In this case, implicit back refs is used for
997 * pointers in the block. Add full back refs for every pointers in the
998 * block, increase lower level extents' reference counts. The original
999 * implicit back refs are entailed to the new block.
1001 * The reference count of the block is greater than one and the tree is
1002 * not the block's owner tree. Add implicit back refs for every pointer in
1003 * the new block, increase lower level extents' reference count.
1005 * Back Reference Key composing:
1007 * The key objectid corresponds to the first byte in the extent,
1008 * The key type is used to differentiate between types of back refs.
1009 * There are different meanings of the key offset for different types
1012 * File extents can be referenced by:
1014 * - multiple snapshots, subvolumes, or different generations in one subvol
1015 * - different files inside a single subvolume
1016 * - different offsets inside a file (bookend extents in file.c)
1018 * The extent ref structure for the implicit back refs has fields for:
1020 * - Objectid of the subvolume root
1021 * - objectid of the file holding the reference
1022 * - original offset in the file
1023 * - how many bookend extents
1025 * The key offset for the implicit back refs is hash of the first
1028 * The extent ref structure for the full back refs has field for:
1030 * - number of pointers in the tree leaf
1032 * The key offset for the implicit back refs is the first byte of
1035 * When a file extent is allocated, The implicit back refs is used.
1036 * the fields are filled in:
1038 * (root_key.objectid, inode objectid, offset in file, 1)
1040 * When a file extent is removed file truncation, we find the
1041 * corresponding implicit back refs and check the following fields:
1043 * (btrfs_header_owner(leaf), inode objectid, offset in file)
1045 * Btree extents can be referenced by:
1047 * - Different subvolumes
1049 * Both the implicit back refs and the full back refs for tree blocks
1050 * only consist of key. The key offset for the implicit back refs is
1051 * objectid of block's owner tree. The key offset for the full back refs
1052 * is the first byte of parent block.
1054 * When implicit back refs is used, information about the lowest key and
1055 * level of the tree block are required. These information are stored in
1056 * tree block info structure.
1060 * is_data == BTRFS_REF_TYPE_BLOCK, tree block type is required,
1061 * is_data == BTRFS_REF_TYPE_DATA, data type is requiried,
1062 * is_data == BTRFS_REF_TYPE_ANY, either type is OK.
1064 int btrfs_get_extent_inline_ref_type(const struct extent_buffer *eb,
1065 struct btrfs_extent_inline_ref *iref,
1066 enum btrfs_inline_ref_type is_data)
1068 int type = btrfs_extent_inline_ref_type(eb, iref);
1069 u64 offset = btrfs_extent_inline_ref_offset(eb, iref);
1071 if (type == BTRFS_TREE_BLOCK_REF_KEY ||
1072 type == BTRFS_SHARED_BLOCK_REF_KEY ||
1073 type == BTRFS_SHARED_DATA_REF_KEY ||
1074 type == BTRFS_EXTENT_DATA_REF_KEY) {
1075 if (is_data == BTRFS_REF_TYPE_BLOCK) {
1076 if (type == BTRFS_TREE_BLOCK_REF_KEY)
1078 if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1079 ASSERT(eb->fs_info);
1081 * Every shared one has parent tree
1082 * block, which must be aligned to
1086 IS_ALIGNED(offset, eb->fs_info->nodesize))
1089 } else if (is_data == BTRFS_REF_TYPE_DATA) {
1090 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1092 if (type == BTRFS_SHARED_DATA_REF_KEY) {
1093 ASSERT(eb->fs_info);
1095 * Every shared one has parent tree
1096 * block, which must be aligned to
1100 IS_ALIGNED(offset, eb->fs_info->nodesize))
1104 ASSERT(is_data == BTRFS_REF_TYPE_ANY);
1109 btrfs_print_leaf((struct extent_buffer *)eb);
1110 btrfs_err(eb->fs_info, "eb %llu invalid extent inline ref type %d",
1114 return BTRFS_REF_TYPE_INVALID;
1117 static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
1119 u32 high_crc = ~(u32)0;
1120 u32 low_crc = ~(u32)0;
1123 lenum = cpu_to_le64(root_objectid);
1124 high_crc = crc32c(high_crc, &lenum, sizeof(lenum));
1125 lenum = cpu_to_le64(owner);
1126 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
1127 lenum = cpu_to_le64(offset);
1128 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
1130 return ((u64)high_crc << 31) ^ (u64)low_crc;
1133 static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
1134 struct btrfs_extent_data_ref *ref)
1136 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
1137 btrfs_extent_data_ref_objectid(leaf, ref),
1138 btrfs_extent_data_ref_offset(leaf, ref));
1141 static int match_extent_data_ref(struct extent_buffer *leaf,
1142 struct btrfs_extent_data_ref *ref,
1143 u64 root_objectid, u64 owner, u64 offset)
1145 if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
1146 btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
1147 btrfs_extent_data_ref_offset(leaf, ref) != offset)
1152 static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
1153 struct btrfs_path *path,
1154 u64 bytenr, u64 parent,
1156 u64 owner, u64 offset)
1158 struct btrfs_root *root = trans->fs_info->extent_root;
1159 struct btrfs_key key;
1160 struct btrfs_extent_data_ref *ref;
1161 struct extent_buffer *leaf;
1167 key.objectid = bytenr;
1169 key.type = BTRFS_SHARED_DATA_REF_KEY;
1170 key.offset = parent;
1172 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1173 key.offset = hash_extent_data_ref(root_objectid,
1178 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1190 leaf = path->nodes[0];
1191 nritems = btrfs_header_nritems(leaf);
1193 if (path->slots[0] >= nritems) {
1194 ret = btrfs_next_leaf(root, path);
1200 leaf = path->nodes[0];
1201 nritems = btrfs_header_nritems(leaf);
1205 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1206 if (key.objectid != bytenr ||
1207 key.type != BTRFS_EXTENT_DATA_REF_KEY)
1210 ref = btrfs_item_ptr(leaf, path->slots[0],
1211 struct btrfs_extent_data_ref);
1213 if (match_extent_data_ref(leaf, ref, root_objectid,
1216 btrfs_release_path(path);
1228 static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
1229 struct btrfs_path *path,
1230 u64 bytenr, u64 parent,
1231 u64 root_objectid, u64 owner,
1232 u64 offset, int refs_to_add)
1234 struct btrfs_root *root = trans->fs_info->extent_root;
1235 struct btrfs_key key;
1236 struct extent_buffer *leaf;
1241 key.objectid = bytenr;
1243 key.type = BTRFS_SHARED_DATA_REF_KEY;
1244 key.offset = parent;
1245 size = sizeof(struct btrfs_shared_data_ref);
1247 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1248 key.offset = hash_extent_data_ref(root_objectid,
1250 size = sizeof(struct btrfs_extent_data_ref);
1253 ret = btrfs_insert_empty_item(trans, root, path, &key, size);
1254 if (ret && ret != -EEXIST)
1257 leaf = path->nodes[0];
1259 struct btrfs_shared_data_ref *ref;
1260 ref = btrfs_item_ptr(leaf, path->slots[0],
1261 struct btrfs_shared_data_ref);
1263 btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
1265 num_refs = btrfs_shared_data_ref_count(leaf, ref);
1266 num_refs += refs_to_add;
1267 btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
1270 struct btrfs_extent_data_ref *ref;
1271 while (ret == -EEXIST) {
1272 ref = btrfs_item_ptr(leaf, path->slots[0],
1273 struct btrfs_extent_data_ref);
1274 if (match_extent_data_ref(leaf, ref, root_objectid,
1277 btrfs_release_path(path);
1279 ret = btrfs_insert_empty_item(trans, root, path, &key,
1281 if (ret && ret != -EEXIST)
1284 leaf = path->nodes[0];
1286 ref = btrfs_item_ptr(leaf, path->slots[0],
1287 struct btrfs_extent_data_ref);
1289 btrfs_set_extent_data_ref_root(leaf, ref,
1291 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
1292 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
1293 btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
1295 num_refs = btrfs_extent_data_ref_count(leaf, ref);
1296 num_refs += refs_to_add;
1297 btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
1300 btrfs_mark_buffer_dirty(leaf);
1303 btrfs_release_path(path);
1307 static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
1308 struct btrfs_path *path,
1309 int refs_to_drop, int *last_ref)
1311 struct btrfs_key key;
1312 struct btrfs_extent_data_ref *ref1 = NULL;
1313 struct btrfs_shared_data_ref *ref2 = NULL;
1314 struct extent_buffer *leaf;
1318 leaf = path->nodes[0];
1319 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1321 if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1322 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1323 struct btrfs_extent_data_ref);
1324 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1325 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1326 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1327 struct btrfs_shared_data_ref);
1328 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1329 } else if (unlikely(key.type == BTRFS_EXTENT_REF_V0_KEY)) {
1330 btrfs_print_v0_err(trans->fs_info);
1331 btrfs_abort_transaction(trans, -EINVAL);
1337 BUG_ON(num_refs < refs_to_drop);
1338 num_refs -= refs_to_drop;
1340 if (num_refs == 0) {
1341 ret = btrfs_del_item(trans, trans->fs_info->extent_root, path);
1344 if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
1345 btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
1346 else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
1347 btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
1348 btrfs_mark_buffer_dirty(leaf);
1353 static noinline u32 extent_data_ref_count(struct btrfs_path *path,
1354 struct btrfs_extent_inline_ref *iref)
1356 struct btrfs_key key;
1357 struct extent_buffer *leaf;
1358 struct btrfs_extent_data_ref *ref1;
1359 struct btrfs_shared_data_ref *ref2;
1363 leaf = path->nodes[0];
1364 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1366 BUG_ON(key.type == BTRFS_EXTENT_REF_V0_KEY);
1369 * If type is invalid, we should have bailed out earlier than
1372 type = btrfs_get_extent_inline_ref_type(leaf, iref, BTRFS_REF_TYPE_DATA);
1373 ASSERT(type != BTRFS_REF_TYPE_INVALID);
1374 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1375 ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
1376 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1378 ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
1379 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1381 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1382 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1383 struct btrfs_extent_data_ref);
1384 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1385 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1386 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1387 struct btrfs_shared_data_ref);
1388 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1395 static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
1396 struct btrfs_path *path,
1397 u64 bytenr, u64 parent,
1400 struct btrfs_root *root = trans->fs_info->extent_root;
1401 struct btrfs_key key;
1404 key.objectid = bytenr;
1406 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1407 key.offset = parent;
1409 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1410 key.offset = root_objectid;
1413 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1419 static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
1420 struct btrfs_path *path,
1421 u64 bytenr, u64 parent,
1424 struct btrfs_key key;
1427 key.objectid = bytenr;
1429 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1430 key.offset = parent;
1432 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1433 key.offset = root_objectid;
1436 ret = btrfs_insert_empty_item(trans, trans->fs_info->extent_root,
1438 btrfs_release_path(path);
1442 static inline int extent_ref_type(u64 parent, u64 owner)
1445 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1447 type = BTRFS_SHARED_BLOCK_REF_KEY;
1449 type = BTRFS_TREE_BLOCK_REF_KEY;
1452 type = BTRFS_SHARED_DATA_REF_KEY;
1454 type = BTRFS_EXTENT_DATA_REF_KEY;
1459 static int find_next_key(struct btrfs_path *path, int level,
1460 struct btrfs_key *key)
1463 for (; level < BTRFS_MAX_LEVEL; level++) {
1464 if (!path->nodes[level])
1466 if (path->slots[level] + 1 >=
1467 btrfs_header_nritems(path->nodes[level]))
1470 btrfs_item_key_to_cpu(path->nodes[level], key,
1471 path->slots[level] + 1);
1473 btrfs_node_key_to_cpu(path->nodes[level], key,
1474 path->slots[level] + 1);
1481 * look for inline back ref. if back ref is found, *ref_ret is set
1482 * to the address of inline back ref, and 0 is returned.
1484 * if back ref isn't found, *ref_ret is set to the address where it
1485 * should be inserted, and -ENOENT is returned.
1487 * if insert is true and there are too many inline back refs, the path
1488 * points to the extent item, and -EAGAIN is returned.
1490 * NOTE: inline back refs are ordered in the same way that back ref
1491 * items in the tree are ordered.
1493 static noinline_for_stack
1494 int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
1495 struct btrfs_path *path,
1496 struct btrfs_extent_inline_ref **ref_ret,
1497 u64 bytenr, u64 num_bytes,
1498 u64 parent, u64 root_objectid,
1499 u64 owner, u64 offset, int insert)
1501 struct btrfs_fs_info *fs_info = trans->fs_info;
1502 struct btrfs_root *root = fs_info->extent_root;
1503 struct btrfs_key key;
1504 struct extent_buffer *leaf;
1505 struct btrfs_extent_item *ei;
1506 struct btrfs_extent_inline_ref *iref;
1516 bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
1519 key.objectid = bytenr;
1520 key.type = BTRFS_EXTENT_ITEM_KEY;
1521 key.offset = num_bytes;
1523 want = extent_ref_type(parent, owner);
1525 extra_size = btrfs_extent_inline_ref_size(want);
1526 path->keep_locks = 1;
1531 * Owner is our level, so we can just add one to get the level for the
1532 * block we are interested in.
1534 if (skinny_metadata && owner < BTRFS_FIRST_FREE_OBJECTID) {
1535 key.type = BTRFS_METADATA_ITEM_KEY;
1540 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
1547 * We may be a newly converted file system which still has the old fat
1548 * extent entries for metadata, so try and see if we have one of those.
1550 if (ret > 0 && skinny_metadata) {
1551 skinny_metadata = false;
1552 if (path->slots[0]) {
1554 btrfs_item_key_to_cpu(path->nodes[0], &key,
1556 if (key.objectid == bytenr &&
1557 key.type == BTRFS_EXTENT_ITEM_KEY &&
1558 key.offset == num_bytes)
1562 key.objectid = bytenr;
1563 key.type = BTRFS_EXTENT_ITEM_KEY;
1564 key.offset = num_bytes;
1565 btrfs_release_path(path);
1570 if (ret && !insert) {
1573 } else if (WARN_ON(ret)) {
1578 leaf = path->nodes[0];
1579 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1580 if (unlikely(item_size < sizeof(*ei))) {
1582 btrfs_print_v0_err(fs_info);
1583 btrfs_abort_transaction(trans, err);
1587 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1588 flags = btrfs_extent_flags(leaf, ei);
1590 ptr = (unsigned long)(ei + 1);
1591 end = (unsigned long)ei + item_size;
1593 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK && !skinny_metadata) {
1594 ptr += sizeof(struct btrfs_tree_block_info);
1598 if (owner >= BTRFS_FIRST_FREE_OBJECTID)
1599 needed = BTRFS_REF_TYPE_DATA;
1601 needed = BTRFS_REF_TYPE_BLOCK;
1609 iref = (struct btrfs_extent_inline_ref *)ptr;
1610 type = btrfs_get_extent_inline_ref_type(leaf, iref, needed);
1611 if (type == BTRFS_REF_TYPE_INVALID) {
1619 ptr += btrfs_extent_inline_ref_size(type);
1623 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1624 struct btrfs_extent_data_ref *dref;
1625 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1626 if (match_extent_data_ref(leaf, dref, root_objectid,
1631 if (hash_extent_data_ref_item(leaf, dref) <
1632 hash_extent_data_ref(root_objectid, owner, offset))
1636 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1638 if (parent == ref_offset) {
1642 if (ref_offset < parent)
1645 if (root_objectid == ref_offset) {
1649 if (ref_offset < root_objectid)
1653 ptr += btrfs_extent_inline_ref_size(type);
1655 if (err == -ENOENT && insert) {
1656 if (item_size + extra_size >=
1657 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
1662 * To add new inline back ref, we have to make sure
1663 * there is no corresponding back ref item.
1664 * For simplicity, we just do not add new inline back
1665 * ref if there is any kind of item for this block
1667 if (find_next_key(path, 0, &key) == 0 &&
1668 key.objectid == bytenr &&
1669 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
1674 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
1677 path->keep_locks = 0;
1678 btrfs_unlock_up_safe(path, 1);
1684 * helper to add new inline back ref
1686 static noinline_for_stack
1687 void setup_inline_extent_backref(struct btrfs_fs_info *fs_info,
1688 struct btrfs_path *path,
1689 struct btrfs_extent_inline_ref *iref,
1690 u64 parent, u64 root_objectid,
1691 u64 owner, u64 offset, int refs_to_add,
1692 struct btrfs_delayed_extent_op *extent_op)
1694 struct extent_buffer *leaf;
1695 struct btrfs_extent_item *ei;
1698 unsigned long item_offset;
1703 leaf = path->nodes[0];
1704 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1705 item_offset = (unsigned long)iref - (unsigned long)ei;
1707 type = extent_ref_type(parent, owner);
1708 size = btrfs_extent_inline_ref_size(type);
1710 btrfs_extend_item(path, size);
1712 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1713 refs = btrfs_extent_refs(leaf, ei);
1714 refs += refs_to_add;
1715 btrfs_set_extent_refs(leaf, ei, refs);
1717 __run_delayed_extent_op(extent_op, leaf, ei);
1719 ptr = (unsigned long)ei + item_offset;
1720 end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
1721 if (ptr < end - size)
1722 memmove_extent_buffer(leaf, ptr + size, ptr,
1725 iref = (struct btrfs_extent_inline_ref *)ptr;
1726 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1727 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1728 struct btrfs_extent_data_ref *dref;
1729 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1730 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1731 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1732 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1733 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1734 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1735 struct btrfs_shared_data_ref *sref;
1736 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1737 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1738 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1739 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1740 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1742 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1744 btrfs_mark_buffer_dirty(leaf);
1747 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1748 struct btrfs_path *path,
1749 struct btrfs_extent_inline_ref **ref_ret,
1750 u64 bytenr, u64 num_bytes, u64 parent,
1751 u64 root_objectid, u64 owner, u64 offset)
1755 ret = lookup_inline_extent_backref(trans, path, ref_ret, bytenr,
1756 num_bytes, parent, root_objectid,
1761 btrfs_release_path(path);
1764 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1765 ret = lookup_tree_block_ref(trans, path, bytenr, parent,
1768 ret = lookup_extent_data_ref(trans, path, bytenr, parent,
1769 root_objectid, owner, offset);
1775 * helper to update/remove inline back ref
1777 static noinline_for_stack
1778 void update_inline_extent_backref(struct btrfs_path *path,
1779 struct btrfs_extent_inline_ref *iref,
1781 struct btrfs_delayed_extent_op *extent_op,
1784 struct extent_buffer *leaf = path->nodes[0];
1785 struct btrfs_extent_item *ei;
1786 struct btrfs_extent_data_ref *dref = NULL;
1787 struct btrfs_shared_data_ref *sref = NULL;
1795 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1796 refs = btrfs_extent_refs(leaf, ei);
1797 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1798 refs += refs_to_mod;
1799 btrfs_set_extent_refs(leaf, ei, refs);
1801 __run_delayed_extent_op(extent_op, leaf, ei);
1804 * If type is invalid, we should have bailed out after
1805 * lookup_inline_extent_backref().
1807 type = btrfs_get_extent_inline_ref_type(leaf, iref, BTRFS_REF_TYPE_ANY);
1808 ASSERT(type != BTRFS_REF_TYPE_INVALID);
1810 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1811 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1812 refs = btrfs_extent_data_ref_count(leaf, dref);
1813 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1814 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1815 refs = btrfs_shared_data_ref_count(leaf, sref);
1818 BUG_ON(refs_to_mod != -1);
1821 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1822 refs += refs_to_mod;
1825 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1826 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1828 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1831 size = btrfs_extent_inline_ref_size(type);
1832 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1833 ptr = (unsigned long)iref;
1834 end = (unsigned long)ei + item_size;
1835 if (ptr + size < end)
1836 memmove_extent_buffer(leaf, ptr, ptr + size,
1839 btrfs_truncate_item(path, item_size, 1);
1841 btrfs_mark_buffer_dirty(leaf);
1844 static noinline_for_stack
1845 int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1846 struct btrfs_path *path,
1847 u64 bytenr, u64 num_bytes, u64 parent,
1848 u64 root_objectid, u64 owner,
1849 u64 offset, int refs_to_add,
1850 struct btrfs_delayed_extent_op *extent_op)
1852 struct btrfs_extent_inline_ref *iref;
1855 ret = lookup_inline_extent_backref(trans, path, &iref, bytenr,
1856 num_bytes, parent, root_objectid,
1859 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
1860 update_inline_extent_backref(path, iref, refs_to_add,
1862 } else if (ret == -ENOENT) {
1863 setup_inline_extent_backref(trans->fs_info, path, iref, parent,
1864 root_objectid, owner, offset,
1865 refs_to_add, extent_op);
1871 static int insert_extent_backref(struct btrfs_trans_handle *trans,
1872 struct btrfs_path *path,
1873 u64 bytenr, u64 parent, u64 root_objectid,
1874 u64 owner, u64 offset, int refs_to_add)
1877 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1878 BUG_ON(refs_to_add != 1);
1879 ret = insert_tree_block_ref(trans, path, bytenr, parent,
1882 ret = insert_extent_data_ref(trans, path, bytenr, parent,
1883 root_objectid, owner, offset,
1889 static int remove_extent_backref(struct btrfs_trans_handle *trans,
1890 struct btrfs_path *path,
1891 struct btrfs_extent_inline_ref *iref,
1892 int refs_to_drop, int is_data, int *last_ref)
1896 BUG_ON(!is_data && refs_to_drop != 1);
1898 update_inline_extent_backref(path, iref, -refs_to_drop, NULL,
1900 } else if (is_data) {
1901 ret = remove_extent_data_ref(trans, path, refs_to_drop,
1905 ret = btrfs_del_item(trans, trans->fs_info->extent_root, path);
1910 static int btrfs_issue_discard(struct block_device *bdev, u64 start, u64 len,
1911 u64 *discarded_bytes)
1914 u64 bytes_left, end;
1915 u64 aligned_start = ALIGN(start, 1 << 9);
1917 if (WARN_ON(start != aligned_start)) {
1918 len -= aligned_start - start;
1919 len = round_down(len, 1 << 9);
1920 start = aligned_start;
1923 *discarded_bytes = 0;
1931 /* Skip any superblocks on this device. */
1932 for (j = 0; j < BTRFS_SUPER_MIRROR_MAX; j++) {
1933 u64 sb_start = btrfs_sb_offset(j);
1934 u64 sb_end = sb_start + BTRFS_SUPER_INFO_SIZE;
1935 u64 size = sb_start - start;
1937 if (!in_range(sb_start, start, bytes_left) &&
1938 !in_range(sb_end, start, bytes_left) &&
1939 !in_range(start, sb_start, BTRFS_SUPER_INFO_SIZE))
1943 * Superblock spans beginning of range. Adjust start and
1946 if (sb_start <= start) {
1947 start += sb_end - start;
1952 bytes_left = end - start;
1957 ret = blkdev_issue_discard(bdev, start >> 9, size >> 9,
1960 *discarded_bytes += size;
1961 else if (ret != -EOPNOTSUPP)
1970 bytes_left = end - start;
1974 ret = blkdev_issue_discard(bdev, start >> 9, bytes_left >> 9,
1977 *discarded_bytes += bytes_left;
1982 int btrfs_discard_extent(struct btrfs_fs_info *fs_info, u64 bytenr,
1983 u64 num_bytes, u64 *actual_bytes)
1986 u64 discarded_bytes = 0;
1987 struct btrfs_bio *bbio = NULL;
1991 * Avoid races with device replace and make sure our bbio has devices
1992 * associated to its stripes that don't go away while we are discarding.
1994 btrfs_bio_counter_inc_blocked(fs_info);
1995 /* Tell the block device(s) that the sectors can be discarded */
1996 ret = btrfs_map_block(fs_info, BTRFS_MAP_DISCARD, bytenr, &num_bytes,
1998 /* Error condition is -ENOMEM */
2000 struct btrfs_bio_stripe *stripe = bbio->stripes;
2004 for (i = 0; i < bbio->num_stripes; i++, stripe++) {
2006 struct request_queue *req_q;
2008 if (!stripe->dev->bdev) {
2009 ASSERT(btrfs_test_opt(fs_info, DEGRADED));
2012 req_q = bdev_get_queue(stripe->dev->bdev);
2013 if (!blk_queue_discard(req_q))
2016 ret = btrfs_issue_discard(stripe->dev->bdev,
2021 discarded_bytes += bytes;
2022 else if (ret != -EOPNOTSUPP)
2023 break; /* Logic errors or -ENOMEM, or -EIO but I don't know how that could happen JDM */
2026 * Just in case we get back EOPNOTSUPP for some reason,
2027 * just ignore the return value so we don't screw up
2028 * people calling discard_extent.
2032 btrfs_put_bbio(bbio);
2034 btrfs_bio_counter_dec(fs_info);
2037 *actual_bytes = discarded_bytes;
2040 if (ret == -EOPNOTSUPP)
2045 /* Can return -ENOMEM */
2046 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
2047 struct btrfs_ref *generic_ref)
2049 struct btrfs_fs_info *fs_info = trans->fs_info;
2050 int old_ref_mod, new_ref_mod;
2053 ASSERT(generic_ref->type != BTRFS_REF_NOT_SET &&
2054 generic_ref->action);
2055 BUG_ON(generic_ref->type == BTRFS_REF_METADATA &&
2056 generic_ref->tree_ref.root == BTRFS_TREE_LOG_OBJECTID);
2058 if (generic_ref->type == BTRFS_REF_METADATA)
2059 ret = btrfs_add_delayed_tree_ref(trans, generic_ref,
2060 NULL, &old_ref_mod, &new_ref_mod);
2062 ret = btrfs_add_delayed_data_ref(trans, generic_ref, 0,
2063 &old_ref_mod, &new_ref_mod);
2065 btrfs_ref_tree_mod(fs_info, generic_ref);
2067 if (ret == 0 && old_ref_mod < 0 && new_ref_mod >= 0)
2068 add_pinned_bytes(fs_info, generic_ref, -1);
2074 * __btrfs_inc_extent_ref - insert backreference for a given extent
2076 * @trans: Handle of transaction
2078 * @node: The delayed ref node used to get the bytenr/length for
2079 * extent whose references are incremented.
2081 * @parent: If this is a shared extent (BTRFS_SHARED_DATA_REF_KEY/
2082 * BTRFS_SHARED_BLOCK_REF_KEY) then it holds the logical
2083 * bytenr of the parent block. Since new extents are always
2084 * created with indirect references, this will only be the case
2085 * when relocating a shared extent. In that case, root_objectid
2086 * will be BTRFS_TREE_RELOC_OBJECTID. Otheriwse, parent must
2089 * @root_objectid: The id of the root where this modification has originated,
2090 * this can be either one of the well-known metadata trees or
2091 * the subvolume id which references this extent.
2093 * @owner: For data extents it is the inode number of the owning file.
2094 * For metadata extents this parameter holds the level in the
2095 * tree of the extent.
2097 * @offset: For metadata extents the offset is ignored and is currently
2098 * always passed as 0. For data extents it is the fileoffset
2099 * this extent belongs to.
2101 * @refs_to_add Number of references to add
2103 * @extent_op Pointer to a structure, holding information necessary when
2104 * updating a tree block's flags
2107 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
2108 struct btrfs_delayed_ref_node *node,
2109 u64 parent, u64 root_objectid,
2110 u64 owner, u64 offset, int refs_to_add,
2111 struct btrfs_delayed_extent_op *extent_op)
2113 struct btrfs_path *path;
2114 struct extent_buffer *leaf;
2115 struct btrfs_extent_item *item;
2116 struct btrfs_key key;
2117 u64 bytenr = node->bytenr;
2118 u64 num_bytes = node->num_bytes;
2122 path = btrfs_alloc_path();
2126 path->reada = READA_FORWARD;
2127 path->leave_spinning = 1;
2128 /* this will setup the path even if it fails to insert the back ref */
2129 ret = insert_inline_extent_backref(trans, path, bytenr, num_bytes,
2130 parent, root_objectid, owner,
2131 offset, refs_to_add, extent_op);
2132 if ((ret < 0 && ret != -EAGAIN) || !ret)
2136 * Ok we had -EAGAIN which means we didn't have space to insert and
2137 * inline extent ref, so just update the reference count and add a
2140 leaf = path->nodes[0];
2141 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2142 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2143 refs = btrfs_extent_refs(leaf, item);
2144 btrfs_set_extent_refs(leaf, item, refs + refs_to_add);
2146 __run_delayed_extent_op(extent_op, leaf, item);
2148 btrfs_mark_buffer_dirty(leaf);
2149 btrfs_release_path(path);
2151 path->reada = READA_FORWARD;
2152 path->leave_spinning = 1;
2153 /* now insert the actual backref */
2154 ret = insert_extent_backref(trans, path, bytenr, parent, root_objectid,
2155 owner, offset, refs_to_add);
2157 btrfs_abort_transaction(trans, ret);
2159 btrfs_free_path(path);
2163 static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
2164 struct btrfs_delayed_ref_node *node,
2165 struct btrfs_delayed_extent_op *extent_op,
2166 int insert_reserved)
2169 struct btrfs_delayed_data_ref *ref;
2170 struct btrfs_key ins;
2175 ins.objectid = node->bytenr;
2176 ins.offset = node->num_bytes;
2177 ins.type = BTRFS_EXTENT_ITEM_KEY;
2179 ref = btrfs_delayed_node_to_data_ref(node);
2180 trace_run_delayed_data_ref(trans->fs_info, node, ref, node->action);
2182 if (node->type == BTRFS_SHARED_DATA_REF_KEY)
2183 parent = ref->parent;
2184 ref_root = ref->root;
2186 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
2188 flags |= extent_op->flags_to_set;
2189 ret = alloc_reserved_file_extent(trans, parent, ref_root,
2190 flags, ref->objectid,
2193 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
2194 ret = __btrfs_inc_extent_ref(trans, node, parent, ref_root,
2195 ref->objectid, ref->offset,
2196 node->ref_mod, extent_op);
2197 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
2198 ret = __btrfs_free_extent(trans, node, parent,
2199 ref_root, ref->objectid,
2200 ref->offset, node->ref_mod,
2208 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
2209 struct extent_buffer *leaf,
2210 struct btrfs_extent_item *ei)
2212 u64 flags = btrfs_extent_flags(leaf, ei);
2213 if (extent_op->update_flags) {
2214 flags |= extent_op->flags_to_set;
2215 btrfs_set_extent_flags(leaf, ei, flags);
2218 if (extent_op->update_key) {
2219 struct btrfs_tree_block_info *bi;
2220 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK));
2221 bi = (struct btrfs_tree_block_info *)(ei + 1);
2222 btrfs_set_tree_block_key(leaf, bi, &extent_op->key);
2226 static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
2227 struct btrfs_delayed_ref_head *head,
2228 struct btrfs_delayed_extent_op *extent_op)
2230 struct btrfs_fs_info *fs_info = trans->fs_info;
2231 struct btrfs_key key;
2232 struct btrfs_path *path;
2233 struct btrfs_extent_item *ei;
2234 struct extent_buffer *leaf;
2238 int metadata = !extent_op->is_data;
2243 if (metadata && !btrfs_fs_incompat(fs_info, SKINNY_METADATA))
2246 path = btrfs_alloc_path();
2250 key.objectid = head->bytenr;
2253 key.type = BTRFS_METADATA_ITEM_KEY;
2254 key.offset = extent_op->level;
2256 key.type = BTRFS_EXTENT_ITEM_KEY;
2257 key.offset = head->num_bytes;
2261 path->reada = READA_FORWARD;
2262 path->leave_spinning = 1;
2263 ret = btrfs_search_slot(trans, fs_info->extent_root, &key, path, 0, 1);
2270 if (path->slots[0] > 0) {
2272 btrfs_item_key_to_cpu(path->nodes[0], &key,
2274 if (key.objectid == head->bytenr &&
2275 key.type == BTRFS_EXTENT_ITEM_KEY &&
2276 key.offset == head->num_bytes)
2280 btrfs_release_path(path);
2283 key.objectid = head->bytenr;
2284 key.offset = head->num_bytes;
2285 key.type = BTRFS_EXTENT_ITEM_KEY;
2294 leaf = path->nodes[0];
2295 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2297 if (unlikely(item_size < sizeof(*ei))) {
2299 btrfs_print_v0_err(fs_info);
2300 btrfs_abort_transaction(trans, err);
2304 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2305 __run_delayed_extent_op(extent_op, leaf, ei);
2307 btrfs_mark_buffer_dirty(leaf);
2309 btrfs_free_path(path);
2313 static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
2314 struct btrfs_delayed_ref_node *node,
2315 struct btrfs_delayed_extent_op *extent_op,
2316 int insert_reserved)
2319 struct btrfs_delayed_tree_ref *ref;
2323 ref = btrfs_delayed_node_to_tree_ref(node);
2324 trace_run_delayed_tree_ref(trans->fs_info, node, ref, node->action);
2326 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2327 parent = ref->parent;
2328 ref_root = ref->root;
2330 if (node->ref_mod != 1) {
2331 btrfs_err(trans->fs_info,
2332 "btree block(%llu) has %d references rather than 1: action %d ref_root %llu parent %llu",
2333 node->bytenr, node->ref_mod, node->action, ref_root,
2337 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
2338 BUG_ON(!extent_op || !extent_op->update_flags);
2339 ret = alloc_reserved_tree_block(trans, node, extent_op);
2340 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
2341 ret = __btrfs_inc_extent_ref(trans, node, parent, ref_root,
2342 ref->level, 0, 1, extent_op);
2343 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
2344 ret = __btrfs_free_extent(trans, node, parent, ref_root,
2345 ref->level, 0, 1, extent_op);
2352 /* helper function to actually process a single delayed ref entry */
2353 static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
2354 struct btrfs_delayed_ref_node *node,
2355 struct btrfs_delayed_extent_op *extent_op,
2356 int insert_reserved)
2360 if (trans->aborted) {
2361 if (insert_reserved)
2362 btrfs_pin_extent(trans->fs_info, node->bytenr,
2363 node->num_bytes, 1);
2367 if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
2368 node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2369 ret = run_delayed_tree_ref(trans, node, extent_op,
2371 else if (node->type == BTRFS_EXTENT_DATA_REF_KEY ||
2372 node->type == BTRFS_SHARED_DATA_REF_KEY)
2373 ret = run_delayed_data_ref(trans, node, extent_op,
2377 if (ret && insert_reserved)
2378 btrfs_pin_extent(trans->fs_info, node->bytenr,
2379 node->num_bytes, 1);
2383 static inline struct btrfs_delayed_ref_node *
2384 select_delayed_ref(struct btrfs_delayed_ref_head *head)
2386 struct btrfs_delayed_ref_node *ref;
2388 if (RB_EMPTY_ROOT(&head->ref_tree.rb_root))
2392 * Select a delayed ref of type BTRFS_ADD_DELAYED_REF first.
2393 * This is to prevent a ref count from going down to zero, which deletes
2394 * the extent item from the extent tree, when there still are references
2395 * to add, which would fail because they would not find the extent item.
2397 if (!list_empty(&head->ref_add_list))
2398 return list_first_entry(&head->ref_add_list,
2399 struct btrfs_delayed_ref_node, add_list);
2401 ref = rb_entry(rb_first_cached(&head->ref_tree),
2402 struct btrfs_delayed_ref_node, ref_node);
2403 ASSERT(list_empty(&ref->add_list));
2407 static void unselect_delayed_ref_head(struct btrfs_delayed_ref_root *delayed_refs,
2408 struct btrfs_delayed_ref_head *head)
2410 spin_lock(&delayed_refs->lock);
2411 head->processing = 0;
2412 delayed_refs->num_heads_ready++;
2413 spin_unlock(&delayed_refs->lock);
2414 btrfs_delayed_ref_unlock(head);
2417 static struct btrfs_delayed_extent_op *cleanup_extent_op(
2418 struct btrfs_delayed_ref_head *head)
2420 struct btrfs_delayed_extent_op *extent_op = head->extent_op;
2425 if (head->must_insert_reserved) {
2426 head->extent_op = NULL;
2427 btrfs_free_delayed_extent_op(extent_op);
2433 static int run_and_cleanup_extent_op(struct btrfs_trans_handle *trans,
2434 struct btrfs_delayed_ref_head *head)
2436 struct btrfs_delayed_extent_op *extent_op;
2439 extent_op = cleanup_extent_op(head);
2442 head->extent_op = NULL;
2443 spin_unlock(&head->lock);
2444 ret = run_delayed_extent_op(trans, head, extent_op);
2445 btrfs_free_delayed_extent_op(extent_op);
2446 return ret ? ret : 1;
2449 void btrfs_cleanup_ref_head_accounting(struct btrfs_fs_info *fs_info,
2450 struct btrfs_delayed_ref_root *delayed_refs,
2451 struct btrfs_delayed_ref_head *head)
2453 int nr_items = 1; /* Dropping this ref head update. */
2455 if (head->total_ref_mod < 0) {
2456 struct btrfs_space_info *space_info;
2460 flags = BTRFS_BLOCK_GROUP_DATA;
2461 else if (head->is_system)
2462 flags = BTRFS_BLOCK_GROUP_SYSTEM;
2464 flags = BTRFS_BLOCK_GROUP_METADATA;
2465 space_info = __find_space_info(fs_info, flags);
2467 percpu_counter_add_batch(&space_info->total_bytes_pinned,
2469 BTRFS_TOTAL_BYTES_PINNED_BATCH);
2472 * We had csum deletions accounted for in our delayed refs rsv,
2473 * we need to drop the csum leaves for this update from our
2476 if (head->is_data) {
2477 spin_lock(&delayed_refs->lock);
2478 delayed_refs->pending_csums -= head->num_bytes;
2479 spin_unlock(&delayed_refs->lock);
2480 nr_items += btrfs_csum_bytes_to_leaves(fs_info,
2485 btrfs_delayed_refs_rsv_release(fs_info, nr_items);
2488 static int cleanup_ref_head(struct btrfs_trans_handle *trans,
2489 struct btrfs_delayed_ref_head *head)
2492 struct btrfs_fs_info *fs_info = trans->fs_info;
2493 struct btrfs_delayed_ref_root *delayed_refs;
2496 delayed_refs = &trans->transaction->delayed_refs;
2498 ret = run_and_cleanup_extent_op(trans, head);
2500 unselect_delayed_ref_head(delayed_refs, head);
2501 btrfs_debug(fs_info, "run_delayed_extent_op returned %d", ret);
2508 * Need to drop our head ref lock and re-acquire the delayed ref lock
2509 * and then re-check to make sure nobody got added.
2511 spin_unlock(&head->lock);
2512 spin_lock(&delayed_refs->lock);
2513 spin_lock(&head->lock);
2514 if (!RB_EMPTY_ROOT(&head->ref_tree.rb_root) || head->extent_op) {
2515 spin_unlock(&head->lock);
2516 spin_unlock(&delayed_refs->lock);
2519 btrfs_delete_ref_head(delayed_refs, head);
2520 spin_unlock(&head->lock);
2521 spin_unlock(&delayed_refs->lock);
2523 if (head->must_insert_reserved) {
2524 btrfs_pin_extent(fs_info, head->bytenr,
2525 head->num_bytes, 1);
2526 if (head->is_data) {
2527 ret = btrfs_del_csums(trans, fs_info, head->bytenr,
2532 btrfs_cleanup_ref_head_accounting(fs_info, delayed_refs, head);
2534 trace_run_delayed_ref_head(fs_info, head, 0);
2535 btrfs_delayed_ref_unlock(head);
2536 btrfs_put_delayed_ref_head(head);
2540 static struct btrfs_delayed_ref_head *btrfs_obtain_ref_head(
2541 struct btrfs_trans_handle *trans)
2543 struct btrfs_delayed_ref_root *delayed_refs =
2544 &trans->transaction->delayed_refs;
2545 struct btrfs_delayed_ref_head *head = NULL;
2548 spin_lock(&delayed_refs->lock);
2549 head = btrfs_select_ref_head(delayed_refs);
2551 spin_unlock(&delayed_refs->lock);
2556 * Grab the lock that says we are going to process all the refs for
2559 ret = btrfs_delayed_ref_lock(delayed_refs, head);
2560 spin_unlock(&delayed_refs->lock);
2563 * We may have dropped the spin lock to get the head mutex lock, and
2564 * that might have given someone else time to free the head. If that's
2565 * true, it has been removed from our list and we can move on.
2568 head = ERR_PTR(-EAGAIN);
2573 static int btrfs_run_delayed_refs_for_head(struct btrfs_trans_handle *trans,
2574 struct btrfs_delayed_ref_head *locked_ref,
2575 unsigned long *run_refs)
2577 struct btrfs_fs_info *fs_info = trans->fs_info;
2578 struct btrfs_delayed_ref_root *delayed_refs;
2579 struct btrfs_delayed_extent_op *extent_op;
2580 struct btrfs_delayed_ref_node *ref;
2581 int must_insert_reserved = 0;
2584 delayed_refs = &trans->transaction->delayed_refs;
2586 lockdep_assert_held(&locked_ref->mutex);
2587 lockdep_assert_held(&locked_ref->lock);
2589 while ((ref = select_delayed_ref(locked_ref))) {
2591 btrfs_check_delayed_seq(fs_info, ref->seq)) {
2592 spin_unlock(&locked_ref->lock);
2593 unselect_delayed_ref_head(delayed_refs, locked_ref);
2599 rb_erase_cached(&ref->ref_node, &locked_ref->ref_tree);
2600 RB_CLEAR_NODE(&ref->ref_node);
2601 if (!list_empty(&ref->add_list))
2602 list_del(&ref->add_list);
2604 * When we play the delayed ref, also correct the ref_mod on
2607 switch (ref->action) {
2608 case BTRFS_ADD_DELAYED_REF:
2609 case BTRFS_ADD_DELAYED_EXTENT:
2610 locked_ref->ref_mod -= ref->ref_mod;
2612 case BTRFS_DROP_DELAYED_REF:
2613 locked_ref->ref_mod += ref->ref_mod;
2618 atomic_dec(&delayed_refs->num_entries);
2621 * Record the must_insert_reserved flag before we drop the
2624 must_insert_reserved = locked_ref->must_insert_reserved;
2625 locked_ref->must_insert_reserved = 0;
2627 extent_op = locked_ref->extent_op;
2628 locked_ref->extent_op = NULL;
2629 spin_unlock(&locked_ref->lock);
2631 ret = run_one_delayed_ref(trans, ref, extent_op,
2632 must_insert_reserved);
2634 btrfs_free_delayed_extent_op(extent_op);
2636 unselect_delayed_ref_head(delayed_refs, locked_ref);
2637 btrfs_put_delayed_ref(ref);
2638 btrfs_debug(fs_info, "run_one_delayed_ref returned %d",
2643 btrfs_put_delayed_ref(ref);
2646 spin_lock(&locked_ref->lock);
2647 btrfs_merge_delayed_refs(trans, delayed_refs, locked_ref);
2654 * Returns 0 on success or if called with an already aborted transaction.
2655 * Returns -ENOMEM or -EIO on failure and will abort the transaction.
2657 static noinline int __btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2660 struct btrfs_fs_info *fs_info = trans->fs_info;
2661 struct btrfs_delayed_ref_root *delayed_refs;
2662 struct btrfs_delayed_ref_head *locked_ref = NULL;
2663 ktime_t start = ktime_get();
2665 unsigned long count = 0;
2666 unsigned long actual_count = 0;
2668 delayed_refs = &trans->transaction->delayed_refs;
2671 locked_ref = btrfs_obtain_ref_head(trans);
2672 if (IS_ERR_OR_NULL(locked_ref)) {
2673 if (PTR_ERR(locked_ref) == -EAGAIN) {
2682 * We need to try and merge add/drops of the same ref since we
2683 * can run into issues with relocate dropping the implicit ref
2684 * and then it being added back again before the drop can
2685 * finish. If we merged anything we need to re-loop so we can
2687 * Or we can get node references of the same type that weren't
2688 * merged when created due to bumps in the tree mod seq, and
2689 * we need to merge them to prevent adding an inline extent
2690 * backref before dropping it (triggering a BUG_ON at
2691 * insert_inline_extent_backref()).
2693 spin_lock(&locked_ref->lock);
2694 btrfs_merge_delayed_refs(trans, delayed_refs, locked_ref);
2696 ret = btrfs_run_delayed_refs_for_head(trans, locked_ref,
2698 if (ret < 0 && ret != -EAGAIN) {
2700 * Error, btrfs_run_delayed_refs_for_head already
2701 * unlocked everything so just bail out
2706 * Success, perform the usual cleanup of a processed
2709 ret = cleanup_ref_head(trans, locked_ref);
2711 /* We dropped our lock, we need to loop. */
2720 * Either success case or btrfs_run_delayed_refs_for_head
2721 * returned -EAGAIN, meaning we need to select another head
2726 } while ((nr != -1 && count < nr) || locked_ref);
2729 * We don't want to include ref heads since we can have empty ref heads
2730 * and those will drastically skew our runtime down since we just do
2731 * accounting, no actual extent tree updates.
2733 if (actual_count > 0) {
2734 u64 runtime = ktime_to_ns(ktime_sub(ktime_get(), start));
2738 * We weigh the current average higher than our current runtime
2739 * to avoid large swings in the average.
2741 spin_lock(&delayed_refs->lock);
2742 avg = fs_info->avg_delayed_ref_runtime * 3 + runtime;
2743 fs_info->avg_delayed_ref_runtime = avg >> 2; /* div by 4 */
2744 spin_unlock(&delayed_refs->lock);
2749 #ifdef SCRAMBLE_DELAYED_REFS
2751 * Normally delayed refs get processed in ascending bytenr order. This
2752 * correlates in most cases to the order added. To expose dependencies on this
2753 * order, we start to process the tree in the middle instead of the beginning
2755 static u64 find_middle(struct rb_root *root)
2757 struct rb_node *n = root->rb_node;
2758 struct btrfs_delayed_ref_node *entry;
2761 u64 first = 0, last = 0;
2765 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2766 first = entry->bytenr;
2770 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2771 last = entry->bytenr;
2776 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2777 WARN_ON(!entry->in_tree);
2779 middle = entry->bytenr;
2792 static inline u64 heads_to_leaves(struct btrfs_fs_info *fs_info, u64 heads)
2796 num_bytes = heads * (sizeof(struct btrfs_extent_item) +
2797 sizeof(struct btrfs_extent_inline_ref));
2798 if (!btrfs_fs_incompat(fs_info, SKINNY_METADATA))
2799 num_bytes += heads * sizeof(struct btrfs_tree_block_info);
2802 * We don't ever fill up leaves all the way so multiply by 2 just to be
2803 * closer to what we're really going to want to use.
2805 return div_u64(num_bytes, BTRFS_LEAF_DATA_SIZE(fs_info));
2809 * Takes the number of bytes to be csumm'ed and figures out how many leaves it
2810 * would require to store the csums for that many bytes.
2812 u64 btrfs_csum_bytes_to_leaves(struct btrfs_fs_info *fs_info, u64 csum_bytes)
2815 u64 num_csums_per_leaf;
2818 csum_size = BTRFS_MAX_ITEM_SIZE(fs_info);
2819 num_csums_per_leaf = div64_u64(csum_size,
2820 (u64)btrfs_super_csum_size(fs_info->super_copy));
2821 num_csums = div64_u64(csum_bytes, fs_info->sectorsize);
2822 num_csums += num_csums_per_leaf - 1;
2823 num_csums = div64_u64(num_csums, num_csums_per_leaf);
2827 bool btrfs_check_space_for_delayed_refs(struct btrfs_fs_info *fs_info)
2829 struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
2830 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
2834 spin_lock(&global_rsv->lock);
2835 reserved = global_rsv->reserved;
2836 spin_unlock(&global_rsv->lock);
2839 * Since the global reserve is just kind of magic we don't really want
2840 * to rely on it to save our bacon, so if our size is more than the
2841 * delayed_refs_rsv and the global rsv then it's time to think about
2844 spin_lock(&delayed_refs_rsv->lock);
2845 reserved += delayed_refs_rsv->reserved;
2846 if (delayed_refs_rsv->size >= reserved)
2848 spin_unlock(&delayed_refs_rsv->lock);
2852 int btrfs_should_throttle_delayed_refs(struct btrfs_trans_handle *trans)
2855 atomic_read(&trans->transaction->delayed_refs.num_entries);
2860 avg_runtime = trans->fs_info->avg_delayed_ref_runtime;
2861 val = num_entries * avg_runtime;
2862 if (val >= NSEC_PER_SEC)
2864 if (val >= NSEC_PER_SEC / 2)
2867 return btrfs_check_space_for_delayed_refs(trans->fs_info);
2871 * this starts processing the delayed reference count updates and
2872 * extent insertions we have queued up so far. count can be
2873 * 0, which means to process everything in the tree at the start
2874 * of the run (but not newly added entries), or it can be some target
2875 * number you'd like to process.
2877 * Returns 0 on success or if called with an aborted transaction
2878 * Returns <0 on error and aborts the transaction
2880 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2881 unsigned long count)
2883 struct btrfs_fs_info *fs_info = trans->fs_info;
2884 struct rb_node *node;
2885 struct btrfs_delayed_ref_root *delayed_refs;
2886 struct btrfs_delayed_ref_head *head;
2888 int run_all = count == (unsigned long)-1;
2890 /* We'll clean this up in btrfs_cleanup_transaction */
2894 if (test_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags))
2897 delayed_refs = &trans->transaction->delayed_refs;
2899 count = atomic_read(&delayed_refs->num_entries) * 2;
2902 #ifdef SCRAMBLE_DELAYED_REFS
2903 delayed_refs->run_delayed_start = find_middle(&delayed_refs->root);
2905 ret = __btrfs_run_delayed_refs(trans, count);
2907 btrfs_abort_transaction(trans, ret);
2912 btrfs_create_pending_block_groups(trans);
2914 spin_lock(&delayed_refs->lock);
2915 node = rb_first_cached(&delayed_refs->href_root);
2917 spin_unlock(&delayed_refs->lock);
2920 head = rb_entry(node, struct btrfs_delayed_ref_head,
2922 refcount_inc(&head->refs);
2923 spin_unlock(&delayed_refs->lock);
2925 /* Mutex was contended, block until it's released and retry. */
2926 mutex_lock(&head->mutex);
2927 mutex_unlock(&head->mutex);
2929 btrfs_put_delayed_ref_head(head);
2937 int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
2938 u64 bytenr, u64 num_bytes, u64 flags,
2939 int level, int is_data)
2941 struct btrfs_delayed_extent_op *extent_op;
2944 extent_op = btrfs_alloc_delayed_extent_op();
2948 extent_op->flags_to_set = flags;
2949 extent_op->update_flags = true;
2950 extent_op->update_key = false;
2951 extent_op->is_data = is_data ? true : false;
2952 extent_op->level = level;
2954 ret = btrfs_add_delayed_extent_op(trans, bytenr, num_bytes, extent_op);
2956 btrfs_free_delayed_extent_op(extent_op);
2960 static noinline int check_delayed_ref(struct btrfs_root *root,
2961 struct btrfs_path *path,
2962 u64 objectid, u64 offset, u64 bytenr)
2964 struct btrfs_delayed_ref_head *head;
2965 struct btrfs_delayed_ref_node *ref;
2966 struct btrfs_delayed_data_ref *data_ref;
2967 struct btrfs_delayed_ref_root *delayed_refs;
2968 struct btrfs_transaction *cur_trans;
2969 struct rb_node *node;
2972 spin_lock(&root->fs_info->trans_lock);
2973 cur_trans = root->fs_info->running_transaction;
2975 refcount_inc(&cur_trans->use_count);
2976 spin_unlock(&root->fs_info->trans_lock);
2980 delayed_refs = &cur_trans->delayed_refs;
2981 spin_lock(&delayed_refs->lock);
2982 head = btrfs_find_delayed_ref_head(delayed_refs, bytenr);
2984 spin_unlock(&delayed_refs->lock);
2985 btrfs_put_transaction(cur_trans);
2989 if (!mutex_trylock(&head->mutex)) {
2990 refcount_inc(&head->refs);
2991 spin_unlock(&delayed_refs->lock);
2993 btrfs_release_path(path);
2996 * Mutex was contended, block until it's released and let
2999 mutex_lock(&head->mutex);
3000 mutex_unlock(&head->mutex);
3001 btrfs_put_delayed_ref_head(head);
3002 btrfs_put_transaction(cur_trans);
3005 spin_unlock(&delayed_refs->lock);
3007 spin_lock(&head->lock);
3009 * XXX: We should replace this with a proper search function in the
3012 for (node = rb_first_cached(&head->ref_tree); node;
3013 node = rb_next(node)) {
3014 ref = rb_entry(node, struct btrfs_delayed_ref_node, ref_node);
3015 /* If it's a shared ref we know a cross reference exists */
3016 if (ref->type != BTRFS_EXTENT_DATA_REF_KEY) {
3021 data_ref = btrfs_delayed_node_to_data_ref(ref);
3024 * If our ref doesn't match the one we're currently looking at
3025 * then we have a cross reference.
3027 if (data_ref->root != root->root_key.objectid ||
3028 data_ref->objectid != objectid ||
3029 data_ref->offset != offset) {
3034 spin_unlock(&head->lock);
3035 mutex_unlock(&head->mutex);
3036 btrfs_put_transaction(cur_trans);
3040 static noinline int check_committed_ref(struct btrfs_root *root,
3041 struct btrfs_path *path,
3042 u64 objectid, u64 offset, u64 bytenr)
3044 struct btrfs_fs_info *fs_info = root->fs_info;
3045 struct btrfs_root *extent_root = fs_info->extent_root;
3046 struct extent_buffer *leaf;
3047 struct btrfs_extent_data_ref *ref;
3048 struct btrfs_extent_inline_ref *iref;
3049 struct btrfs_extent_item *ei;
3050 struct btrfs_key key;
3055 key.objectid = bytenr;
3056 key.offset = (u64)-1;
3057 key.type = BTRFS_EXTENT_ITEM_KEY;
3059 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
3062 BUG_ON(ret == 0); /* Corruption */
3065 if (path->slots[0] == 0)
3069 leaf = path->nodes[0];
3070 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
3072 if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY)
3076 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
3077 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
3079 if (item_size != sizeof(*ei) +
3080 btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY))
3083 if (btrfs_extent_generation(leaf, ei) <=
3084 btrfs_root_last_snapshot(&root->root_item))
3087 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
3089 type = btrfs_get_extent_inline_ref_type(leaf, iref, BTRFS_REF_TYPE_DATA);
3090 if (type != BTRFS_EXTENT_DATA_REF_KEY)
3093 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
3094 if (btrfs_extent_refs(leaf, ei) !=
3095 btrfs_extent_data_ref_count(leaf, ref) ||
3096 btrfs_extent_data_ref_root(leaf, ref) !=
3097 root->root_key.objectid ||
3098 btrfs_extent_data_ref_objectid(leaf, ref) != objectid ||
3099 btrfs_extent_data_ref_offset(leaf, ref) != offset)
3107 int btrfs_cross_ref_exist(struct btrfs_root *root, u64 objectid, u64 offset,
3110 struct btrfs_path *path;
3113 path = btrfs_alloc_path();
3118 ret = check_committed_ref(root, path, objectid,
3120 if (ret && ret != -ENOENT)
3123 ret = check_delayed_ref(root, path, objectid, offset, bytenr);
3124 } while (ret == -EAGAIN);
3127 btrfs_free_path(path);
3128 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
3133 static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
3134 struct btrfs_root *root,
3135 struct extent_buffer *buf,
3136 int full_backref, int inc)
3138 struct btrfs_fs_info *fs_info = root->fs_info;
3144 struct btrfs_key key;
3145 struct btrfs_file_extent_item *fi;
3146 struct btrfs_ref generic_ref = { 0 };
3147 bool for_reloc = btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC);
3153 if (btrfs_is_testing(fs_info))
3156 ref_root = btrfs_header_owner(buf);
3157 nritems = btrfs_header_nritems(buf);
3158 level = btrfs_header_level(buf);
3160 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state) && level == 0)
3164 parent = buf->start;
3168 action = BTRFS_ADD_DELAYED_REF;
3170 action = BTRFS_DROP_DELAYED_REF;
3172 for (i = 0; i < nritems; i++) {
3174 btrfs_item_key_to_cpu(buf, &key, i);
3175 if (key.type != BTRFS_EXTENT_DATA_KEY)
3177 fi = btrfs_item_ptr(buf, i,
3178 struct btrfs_file_extent_item);
3179 if (btrfs_file_extent_type(buf, fi) ==
3180 BTRFS_FILE_EXTENT_INLINE)
3182 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
3186 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
3187 key.offset -= btrfs_file_extent_offset(buf, fi);
3188 btrfs_init_generic_ref(&generic_ref, action, bytenr,
3190 generic_ref.real_root = root->root_key.objectid;
3191 btrfs_init_data_ref(&generic_ref, ref_root, key.objectid,
3193 generic_ref.skip_qgroup = for_reloc;
3195 ret = btrfs_inc_extent_ref(trans, &generic_ref);
3197 ret = btrfs_free_extent(trans, &generic_ref);
3201 bytenr = btrfs_node_blockptr(buf, i);
3202 num_bytes = fs_info->nodesize;
3203 btrfs_init_generic_ref(&generic_ref, action, bytenr,
3205 generic_ref.real_root = root->root_key.objectid;
3206 btrfs_init_tree_ref(&generic_ref, level - 1, ref_root);
3207 generic_ref.skip_qgroup = for_reloc;
3209 ret = btrfs_inc_extent_ref(trans, &generic_ref);
3211 ret = btrfs_free_extent(trans, &generic_ref);
3221 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
3222 struct extent_buffer *buf, int full_backref)
3224 return __btrfs_mod_ref(trans, root, buf, full_backref, 1);
3227 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
3228 struct extent_buffer *buf, int full_backref)
3230 return __btrfs_mod_ref(trans, root, buf, full_backref, 0);
3233 static int write_one_cache_group(struct btrfs_trans_handle *trans,
3234 struct btrfs_path *path,
3235 struct btrfs_block_group_cache *cache)
3237 struct btrfs_fs_info *fs_info = trans->fs_info;
3239 struct btrfs_root *extent_root = fs_info->extent_root;
3241 struct extent_buffer *leaf;
3243 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
3250 leaf = path->nodes[0];
3251 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
3252 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
3253 btrfs_mark_buffer_dirty(leaf);
3255 btrfs_release_path(path);
3260 static struct btrfs_block_group_cache *next_block_group(
3261 struct btrfs_block_group_cache *cache)
3263 struct btrfs_fs_info *fs_info = cache->fs_info;
3264 struct rb_node *node;
3266 spin_lock(&fs_info->block_group_cache_lock);
3268 /* If our block group was removed, we need a full search. */
3269 if (RB_EMPTY_NODE(&cache->cache_node)) {
3270 const u64 next_bytenr = cache->key.objectid + cache->key.offset;
3272 spin_unlock(&fs_info->block_group_cache_lock);
3273 btrfs_put_block_group(cache);
3274 cache = btrfs_lookup_first_block_group(fs_info, next_bytenr); return cache;
3276 node = rb_next(&cache->cache_node);
3277 btrfs_put_block_group(cache);
3279 cache = rb_entry(node, struct btrfs_block_group_cache,
3281 btrfs_get_block_group(cache);
3284 spin_unlock(&fs_info->block_group_cache_lock);
3288 static int cache_save_setup(struct btrfs_block_group_cache *block_group,
3289 struct btrfs_trans_handle *trans,
3290 struct btrfs_path *path)
3292 struct btrfs_fs_info *fs_info = block_group->fs_info;
3293 struct btrfs_root *root = fs_info->tree_root;
3294 struct inode *inode = NULL;
3295 struct extent_changeset *data_reserved = NULL;
3297 int dcs = BTRFS_DC_ERROR;
3303 * If this block group is smaller than 100 megs don't bother caching the
3306 if (block_group->key.offset < (100 * SZ_1M)) {
3307 spin_lock(&block_group->lock);
3308 block_group->disk_cache_state = BTRFS_DC_WRITTEN;
3309 spin_unlock(&block_group->lock);
3316 inode = lookup_free_space_inode(block_group, path);
3317 if (IS_ERR(inode) && PTR_ERR(inode) != -ENOENT) {
3318 ret = PTR_ERR(inode);
3319 btrfs_release_path(path);
3323 if (IS_ERR(inode)) {
3327 if (block_group->ro)
3330 ret = create_free_space_inode(trans, block_group, path);
3337 * We want to set the generation to 0, that way if anything goes wrong
3338 * from here on out we know not to trust this cache when we load up next
3341 BTRFS_I(inode)->generation = 0;
3342 ret = btrfs_update_inode(trans, root, inode);
3345 * So theoretically we could recover from this, simply set the
3346 * super cache generation to 0 so we know to invalidate the
3347 * cache, but then we'd have to keep track of the block groups
3348 * that fail this way so we know we _have_ to reset this cache
3349 * before the next commit or risk reading stale cache. So to
3350 * limit our exposure to horrible edge cases lets just abort the
3351 * transaction, this only happens in really bad situations
3354 btrfs_abort_transaction(trans, ret);
3359 /* We've already setup this transaction, go ahead and exit */
3360 if (block_group->cache_generation == trans->transid &&
3361 i_size_read(inode)) {
3362 dcs = BTRFS_DC_SETUP;
3366 if (i_size_read(inode) > 0) {
3367 ret = btrfs_check_trunc_cache_free_space(fs_info,
3368 &fs_info->global_block_rsv);
3372 ret = btrfs_truncate_free_space_cache(trans, NULL, inode);
3377 spin_lock(&block_group->lock);
3378 if (block_group->cached != BTRFS_CACHE_FINISHED ||
3379 !btrfs_test_opt(fs_info, SPACE_CACHE)) {
3381 * don't bother trying to write stuff out _if_
3382 * a) we're not cached,
3383 * b) we're with nospace_cache mount option,
3384 * c) we're with v2 space_cache (FREE_SPACE_TREE).
3386 dcs = BTRFS_DC_WRITTEN;
3387 spin_unlock(&block_group->lock);
3390 spin_unlock(&block_group->lock);
3393 * We hit an ENOSPC when setting up the cache in this transaction, just
3394 * skip doing the setup, we've already cleared the cache so we're safe.
3396 if (test_bit(BTRFS_TRANS_CACHE_ENOSPC, &trans->transaction->flags)) {
3402 * Try to preallocate enough space based on how big the block group is.
3403 * Keep in mind this has to include any pinned space which could end up
3404 * taking up quite a bit since it's not folded into the other space
3407 num_pages = div_u64(block_group->key.offset, SZ_256M);
3412 num_pages *= PAGE_SIZE;
3414 ret = btrfs_check_data_free_space(inode, &data_reserved, 0, num_pages);
3418 ret = btrfs_prealloc_file_range_trans(inode, trans, 0, 0, num_pages,
3419 num_pages, num_pages,
3422 * Our cache requires contiguous chunks so that we don't modify a bunch
3423 * of metadata or split extents when writing the cache out, which means
3424 * we can enospc if we are heavily fragmented in addition to just normal
3425 * out of space conditions. So if we hit this just skip setting up any
3426 * other block groups for this transaction, maybe we'll unpin enough
3427 * space the next time around.
3430 dcs = BTRFS_DC_SETUP;
3431 else if (ret == -ENOSPC)
3432 set_bit(BTRFS_TRANS_CACHE_ENOSPC, &trans->transaction->flags);
3437 btrfs_release_path(path);
3439 spin_lock(&block_group->lock);
3440 if (!ret && dcs == BTRFS_DC_SETUP)
3441 block_group->cache_generation = trans->transid;
3442 block_group->disk_cache_state = dcs;
3443 spin_unlock(&block_group->lock);
3445 extent_changeset_free(data_reserved);
3449 int btrfs_setup_space_cache(struct btrfs_trans_handle *trans)
3451 struct btrfs_fs_info *fs_info = trans->fs_info;
3452 struct btrfs_block_group_cache *cache, *tmp;
3453 struct btrfs_transaction *cur_trans = trans->transaction;
3454 struct btrfs_path *path;
3456 if (list_empty(&cur_trans->dirty_bgs) ||
3457 !btrfs_test_opt(fs_info, SPACE_CACHE))
3460 path = btrfs_alloc_path();
3464 /* Could add new block groups, use _safe just in case */
3465 list_for_each_entry_safe(cache, tmp, &cur_trans->dirty_bgs,
3467 if (cache->disk_cache_state == BTRFS_DC_CLEAR)
3468 cache_save_setup(cache, trans, path);
3471 btrfs_free_path(path);
3476 * transaction commit does final block group cache writeback during a
3477 * critical section where nothing is allowed to change the FS. This is
3478 * required in order for the cache to actually match the block group,
3479 * but can introduce a lot of latency into the commit.
3481 * So, btrfs_start_dirty_block_groups is here to kick off block group
3482 * cache IO. There's a chance we'll have to redo some of it if the
3483 * block group changes again during the commit, but it greatly reduces
3484 * the commit latency by getting rid of the easy block groups while
3485 * we're still allowing others to join the commit.
3487 int btrfs_start_dirty_block_groups(struct btrfs_trans_handle *trans)
3489 struct btrfs_fs_info *fs_info = trans->fs_info;
3490 struct btrfs_block_group_cache *cache;
3491 struct btrfs_transaction *cur_trans = trans->transaction;
3494 struct btrfs_path *path = NULL;
3496 struct list_head *io = &cur_trans->io_bgs;
3497 int num_started = 0;
3500 spin_lock(&cur_trans->dirty_bgs_lock);
3501 if (list_empty(&cur_trans->dirty_bgs)) {
3502 spin_unlock(&cur_trans->dirty_bgs_lock);
3505 list_splice_init(&cur_trans->dirty_bgs, &dirty);
3506 spin_unlock(&cur_trans->dirty_bgs_lock);
3510 * make sure all the block groups on our dirty list actually
3513 btrfs_create_pending_block_groups(trans);
3516 path = btrfs_alloc_path();
3522 * cache_write_mutex is here only to save us from balance or automatic
3523 * removal of empty block groups deleting this block group while we are
3524 * writing out the cache
3526 mutex_lock(&trans->transaction->cache_write_mutex);
3527 while (!list_empty(&dirty)) {
3528 bool drop_reserve = true;
3530 cache = list_first_entry(&dirty,
3531 struct btrfs_block_group_cache,
3534 * this can happen if something re-dirties a block
3535 * group that is already under IO. Just wait for it to
3536 * finish and then do it all again
3538 if (!list_empty(&cache->io_list)) {
3539 list_del_init(&cache->io_list);
3540 btrfs_wait_cache_io(trans, cache, path);
3541 btrfs_put_block_group(cache);
3546 * btrfs_wait_cache_io uses the cache->dirty_list to decide
3547 * if it should update the cache_state. Don't delete
3548 * until after we wait.
3550 * Since we're not running in the commit critical section
3551 * we need the dirty_bgs_lock to protect from update_block_group
3553 spin_lock(&cur_trans->dirty_bgs_lock);
3554 list_del_init(&cache->dirty_list);
3555 spin_unlock(&cur_trans->dirty_bgs_lock);
3559 cache_save_setup(cache, trans, path);
3561 if (cache->disk_cache_state == BTRFS_DC_SETUP) {
3562 cache->io_ctl.inode = NULL;
3563 ret = btrfs_write_out_cache(trans, cache, path);
3564 if (ret == 0 && cache->io_ctl.inode) {
3569 * The cache_write_mutex is protecting the
3570 * io_list, also refer to the definition of
3571 * btrfs_transaction::io_bgs for more details
3573 list_add_tail(&cache->io_list, io);
3576 * if we failed to write the cache, the
3577 * generation will be bad and life goes on
3583 ret = write_one_cache_group(trans, path, cache);
3585 * Our block group might still be attached to the list
3586 * of new block groups in the transaction handle of some
3587 * other task (struct btrfs_trans_handle->new_bgs). This
3588 * means its block group item isn't yet in the extent
3589 * tree. If this happens ignore the error, as we will
3590 * try again later in the critical section of the
3591 * transaction commit.
3593 if (ret == -ENOENT) {
3595 spin_lock(&cur_trans->dirty_bgs_lock);
3596 if (list_empty(&cache->dirty_list)) {
3597 list_add_tail(&cache->dirty_list,
3598 &cur_trans->dirty_bgs);
3599 btrfs_get_block_group(cache);
3600 drop_reserve = false;
3602 spin_unlock(&cur_trans->dirty_bgs_lock);
3604 btrfs_abort_transaction(trans, ret);
3608 /* if it's not on the io list, we need to put the block group */
3610 btrfs_put_block_group(cache);
3612 btrfs_delayed_refs_rsv_release(fs_info, 1);
3618 * Avoid blocking other tasks for too long. It might even save
3619 * us from writing caches for block groups that are going to be
3622 mutex_unlock(&trans->transaction->cache_write_mutex);
3623 mutex_lock(&trans->transaction->cache_write_mutex);
3625 mutex_unlock(&trans->transaction->cache_write_mutex);
3628 * go through delayed refs for all the stuff we've just kicked off
3629 * and then loop back (just once)
3631 ret = btrfs_run_delayed_refs(trans, 0);
3632 if (!ret && loops == 0) {
3634 spin_lock(&cur_trans->dirty_bgs_lock);
3635 list_splice_init(&cur_trans->dirty_bgs, &dirty);
3637 * dirty_bgs_lock protects us from concurrent block group
3638 * deletes too (not just cache_write_mutex).
3640 if (!list_empty(&dirty)) {
3641 spin_unlock(&cur_trans->dirty_bgs_lock);
3644 spin_unlock(&cur_trans->dirty_bgs_lock);
3645 } else if (ret < 0) {
3646 btrfs_cleanup_dirty_bgs(cur_trans, fs_info);
3649 btrfs_free_path(path);
3653 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans)
3655 struct btrfs_fs_info *fs_info = trans->fs_info;
3656 struct btrfs_block_group_cache *cache;
3657 struct btrfs_transaction *cur_trans = trans->transaction;
3660 struct btrfs_path *path;
3661 struct list_head *io = &cur_trans->io_bgs;
3662 int num_started = 0;
3664 path = btrfs_alloc_path();
3669 * Even though we are in the critical section of the transaction commit,
3670 * we can still have concurrent tasks adding elements to this
3671 * transaction's list of dirty block groups. These tasks correspond to
3672 * endio free space workers started when writeback finishes for a
3673 * space cache, which run inode.c:btrfs_finish_ordered_io(), and can
3674 * allocate new block groups as a result of COWing nodes of the root
3675 * tree when updating the free space inode. The writeback for the space
3676 * caches is triggered by an earlier call to
3677 * btrfs_start_dirty_block_groups() and iterations of the following
3679 * Also we want to do the cache_save_setup first and then run the
3680 * delayed refs to make sure we have the best chance at doing this all
3683 spin_lock(&cur_trans->dirty_bgs_lock);
3684 while (!list_empty(&cur_trans->dirty_bgs)) {
3685 cache = list_first_entry(&cur_trans->dirty_bgs,
3686 struct btrfs_block_group_cache,
3690 * this can happen if cache_save_setup re-dirties a block
3691 * group that is already under IO. Just wait for it to
3692 * finish and then do it all again
3694 if (!list_empty(&cache->io_list)) {
3695 spin_unlock(&cur_trans->dirty_bgs_lock);
3696 list_del_init(&cache->io_list);
3697 btrfs_wait_cache_io(trans, cache, path);
3698 btrfs_put_block_group(cache);
3699 spin_lock(&cur_trans->dirty_bgs_lock);
3703 * don't remove from the dirty list until after we've waited
3706 list_del_init(&cache->dirty_list);
3707 spin_unlock(&cur_trans->dirty_bgs_lock);
3710 cache_save_setup(cache, trans, path);
3713 ret = btrfs_run_delayed_refs(trans,
3714 (unsigned long) -1);
3716 if (!ret && cache->disk_cache_state == BTRFS_DC_SETUP) {
3717 cache->io_ctl.inode = NULL;
3718 ret = btrfs_write_out_cache(trans, cache, path);
3719 if (ret == 0 && cache->io_ctl.inode) {
3722 list_add_tail(&cache->io_list, io);
3725 * if we failed to write the cache, the
3726 * generation will be bad and life goes on
3732 ret = write_one_cache_group(trans, path, cache);
3734 * One of the free space endio workers might have
3735 * created a new block group while updating a free space
3736 * cache's inode (at inode.c:btrfs_finish_ordered_io())
3737 * and hasn't released its transaction handle yet, in
3738 * which case the new block group is still attached to
3739 * its transaction handle and its creation has not
3740 * finished yet (no block group item in the extent tree
3741 * yet, etc). If this is the case, wait for all free
3742 * space endio workers to finish and retry. This is a
3743 * a very rare case so no need for a more efficient and
3746 if (ret == -ENOENT) {
3747 wait_event(cur_trans->writer_wait,
3748 atomic_read(&cur_trans->num_writers) == 1);
3749 ret = write_one_cache_group(trans, path, cache);
3752 btrfs_abort_transaction(trans, ret);
3755 /* if its not on the io list, we need to put the block group */
3757 btrfs_put_block_group(cache);
3758 btrfs_delayed_refs_rsv_release(fs_info, 1);
3759 spin_lock(&cur_trans->dirty_bgs_lock);
3761 spin_unlock(&cur_trans->dirty_bgs_lock);
3764 * Refer to the definition of io_bgs member for details why it's safe
3765 * to use it without any locking
3767 while (!list_empty(io)) {
3768 cache = list_first_entry(io, struct btrfs_block_group_cache,
3770 list_del_init(&cache->io_list);
3771 btrfs_wait_cache_io(trans, cache, path);
3772 btrfs_put_block_group(cache);
3775 btrfs_free_path(path);
3779 int btrfs_extent_readonly(struct btrfs_fs_info *fs_info, u64 bytenr)
3781 struct btrfs_block_group_cache *block_group;
3784 block_group = btrfs_lookup_block_group(fs_info, bytenr);
3785 if (!block_group || block_group->ro)
3788 btrfs_put_block_group(block_group);
3792 bool btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr)
3794 struct btrfs_block_group_cache *bg;
3797 bg = btrfs_lookup_block_group(fs_info, bytenr);
3801 spin_lock(&bg->lock);
3805 atomic_inc(&bg->nocow_writers);
3806 spin_unlock(&bg->lock);
3808 /* no put on block group, done by btrfs_dec_nocow_writers */
3810 btrfs_put_block_group(bg);
3816 void btrfs_dec_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr)
3818 struct btrfs_block_group_cache *bg;
3820 bg = btrfs_lookup_block_group(fs_info, bytenr);
3822 if (atomic_dec_and_test(&bg->nocow_writers))
3823 wake_up_var(&bg->nocow_writers);
3825 * Once for our lookup and once for the lookup done by a previous call
3826 * to btrfs_inc_nocow_writers()
3828 btrfs_put_block_group(bg);
3829 btrfs_put_block_group(bg);
3832 void btrfs_wait_nocow_writers(struct btrfs_block_group_cache *bg)
3834 wait_var_event(&bg->nocow_writers, !atomic_read(&bg->nocow_writers));
3837 static const char *alloc_name(u64 flags)
3840 case BTRFS_BLOCK_GROUP_METADATA|BTRFS_BLOCK_GROUP_DATA:
3842 case BTRFS_BLOCK_GROUP_METADATA:
3844 case BTRFS_BLOCK_GROUP_DATA:
3846 case BTRFS_BLOCK_GROUP_SYSTEM:
3850 return "invalid-combination";
3854 static int create_space_info(struct btrfs_fs_info *info, u64 flags)
3857 struct btrfs_space_info *space_info;
3861 space_info = kzalloc(sizeof(*space_info), GFP_NOFS);
3865 ret = percpu_counter_init(&space_info->total_bytes_pinned, 0,
3872 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
3873 INIT_LIST_HEAD(&space_info->block_groups[i]);
3874 init_rwsem(&space_info->groups_sem);
3875 spin_lock_init(&space_info->lock);
3876 space_info->flags = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
3877 space_info->force_alloc = CHUNK_ALLOC_NO_FORCE;
3878 init_waitqueue_head(&space_info->wait);
3879 INIT_LIST_HEAD(&space_info->ro_bgs);
3880 INIT_LIST_HEAD(&space_info->tickets);
3881 INIT_LIST_HEAD(&space_info->priority_tickets);
3883 ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype,
3884 info->space_info_kobj, "%s",
3885 alloc_name(space_info->flags));
3887 kobject_put(&space_info->kobj);
3891 list_add_rcu(&space_info->list, &info->space_info);
3892 if (flags & BTRFS_BLOCK_GROUP_DATA)
3893 info->data_sinfo = space_info;
3898 static void update_space_info(struct btrfs_fs_info *info, u64 flags,
3899 u64 total_bytes, u64 bytes_used,
3901 struct btrfs_space_info **space_info)
3903 struct btrfs_space_info *found;
3906 factor = btrfs_bg_type_to_factor(flags);
3908 found = __find_space_info(info, flags);
3910 spin_lock(&found->lock);
3911 found->total_bytes += total_bytes;
3912 found->disk_total += total_bytes * factor;
3913 found->bytes_used += bytes_used;
3914 found->disk_used += bytes_used * factor;
3915 found->bytes_readonly += bytes_readonly;
3916 if (total_bytes > 0)
3918 space_info_add_new_bytes(info, found, total_bytes -
3919 bytes_used - bytes_readonly);
3920 spin_unlock(&found->lock);
3921 *space_info = found;
3924 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
3926 u64 extra_flags = chunk_to_extended(flags) &
3927 BTRFS_EXTENDED_PROFILE_MASK;
3929 write_seqlock(&fs_info->profiles_lock);
3930 if (flags & BTRFS_BLOCK_GROUP_DATA)
3931 fs_info->avail_data_alloc_bits |= extra_flags;
3932 if (flags & BTRFS_BLOCK_GROUP_METADATA)
3933 fs_info->avail_metadata_alloc_bits |= extra_flags;
3934 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
3935 fs_info->avail_system_alloc_bits |= extra_flags;
3936 write_sequnlock(&fs_info->profiles_lock);
3940 * returns target flags in extended format or 0 if restripe for this
3941 * chunk_type is not in progress
3943 * should be called with balance_lock held
3945 static u64 get_restripe_target(struct btrfs_fs_info *fs_info, u64 flags)
3947 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3953 if (flags & BTRFS_BLOCK_GROUP_DATA &&
3954 bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3955 target = BTRFS_BLOCK_GROUP_DATA | bctl->data.target;
3956 } else if (flags & BTRFS_BLOCK_GROUP_SYSTEM &&
3957 bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3958 target = BTRFS_BLOCK_GROUP_SYSTEM | bctl->sys.target;
3959 } else if (flags & BTRFS_BLOCK_GROUP_METADATA &&
3960 bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3961 target = BTRFS_BLOCK_GROUP_METADATA | bctl->meta.target;
3968 * @flags: available profiles in extended format (see ctree.h)
3970 * Returns reduced profile in chunk format. If profile changing is in
3971 * progress (either running or paused) picks the target profile (if it's
3972 * already available), otherwise falls back to plain reducing.
3974 static u64 btrfs_reduce_alloc_profile(struct btrfs_fs_info *fs_info, u64 flags)
3976 u64 num_devices = fs_info->fs_devices->rw_devices;
3982 * see if restripe for this chunk_type is in progress, if so
3983 * try to reduce to the target profile
3985 spin_lock(&fs_info->balance_lock);
3986 target = get_restripe_target(fs_info, flags);
3988 /* pick target profile only if it's already available */
3989 if ((flags & target) & BTRFS_EXTENDED_PROFILE_MASK) {
3990 spin_unlock(&fs_info->balance_lock);
3991 return extended_to_chunk(target);
3994 spin_unlock(&fs_info->balance_lock);
3996 /* First, mask out the RAID levels which aren't possible */
3997 for (raid_type = 0; raid_type < BTRFS_NR_RAID_TYPES; raid_type++) {
3998 if (num_devices >= btrfs_raid_array[raid_type].devs_min)
3999 allowed |= btrfs_raid_array[raid_type].bg_flag;
4003 if (allowed & BTRFS_BLOCK_GROUP_RAID6)
4004 allowed = BTRFS_BLOCK_GROUP_RAID6;
4005 else if (allowed & BTRFS_BLOCK_GROUP_RAID5)
4006 allowed = BTRFS_BLOCK_GROUP_RAID5;
4007 else if (allowed & BTRFS_BLOCK_GROUP_RAID10)
4008 allowed = BTRFS_BLOCK_GROUP_RAID10;
4009 else if (allowed & BTRFS_BLOCK_GROUP_RAID1)
4010 allowed = BTRFS_BLOCK_GROUP_RAID1;
4011 else if (allowed & BTRFS_BLOCK_GROUP_RAID0)
4012 allowed = BTRFS_BLOCK_GROUP_RAID0;
4014 flags &= ~BTRFS_BLOCK_GROUP_PROFILE_MASK;
4016 return extended_to_chunk(flags | allowed);
4019 static u64 get_alloc_profile(struct btrfs_fs_info *fs_info, u64 orig_flags)
4026 seq = read_seqbegin(&fs_info->profiles_lock);
4028 if (flags & BTRFS_BLOCK_GROUP_DATA)
4029 flags |= fs_info->avail_data_alloc_bits;
4030 else if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
4031 flags |= fs_info->avail_system_alloc_bits;
4032 else if (flags & BTRFS_BLOCK_GROUP_METADATA)
4033 flags |= fs_info->avail_metadata_alloc_bits;
4034 } while (read_seqretry(&fs_info->profiles_lock, seq));
4036 return btrfs_reduce_alloc_profile(fs_info, flags);
4039 static u64 get_alloc_profile_by_root(struct btrfs_root *root, int data)
4041 struct btrfs_fs_info *fs_info = root->fs_info;
4046 flags = BTRFS_BLOCK_GROUP_DATA;
4047 else if (root == fs_info->chunk_root)
4048 flags = BTRFS_BLOCK_GROUP_SYSTEM;
4050 flags = BTRFS_BLOCK_GROUP_METADATA;
4052 ret = get_alloc_profile(fs_info, flags);
4056 u64 btrfs_data_alloc_profile(struct btrfs_fs_info *fs_info)
4058 return get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_DATA);
4061 u64 btrfs_metadata_alloc_profile(struct btrfs_fs_info *fs_info)
4063 return get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_METADATA);
4066 u64 btrfs_system_alloc_profile(struct btrfs_fs_info *fs_info)
4068 return get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
4071 static u64 btrfs_space_info_used(struct btrfs_space_info *s_info,
4072 bool may_use_included)
4075 return s_info->bytes_used + s_info->bytes_reserved +
4076 s_info->bytes_pinned + s_info->bytes_readonly +
4077 (may_use_included ? s_info->bytes_may_use : 0);
4080 int btrfs_alloc_data_chunk_ondemand(struct btrfs_inode *inode, u64 bytes)
4082 struct btrfs_root *root = inode->root;
4083 struct btrfs_fs_info *fs_info = root->fs_info;
4084 struct btrfs_space_info *data_sinfo = fs_info->data_sinfo;
4087 int need_commit = 2;
4088 int have_pinned_space;
4090 /* make sure bytes are sectorsize aligned */
4091 bytes = ALIGN(bytes, fs_info->sectorsize);
4093 if (btrfs_is_free_space_inode(inode)) {
4095 ASSERT(current->journal_info);
4099 /* make sure we have enough space to handle the data first */
4100 spin_lock(&data_sinfo->lock);
4101 used = btrfs_space_info_used(data_sinfo, true);
4103 if (used + bytes > data_sinfo->total_bytes) {
4104 struct btrfs_trans_handle *trans;
4107 * if we don't have enough free bytes in this space then we need
4108 * to alloc a new chunk.
4110 if (!data_sinfo->full) {
4113 data_sinfo->force_alloc = CHUNK_ALLOC_FORCE;
4114 spin_unlock(&data_sinfo->lock);
4116 alloc_target = btrfs_data_alloc_profile(fs_info);
4118 * It is ugly that we don't call nolock join
4119 * transaction for the free space inode case here.
4120 * But it is safe because we only do the data space
4121 * reservation for the free space cache in the
4122 * transaction context, the common join transaction
4123 * just increase the counter of the current transaction
4124 * handler, doesn't try to acquire the trans_lock of
4127 trans = btrfs_join_transaction(root);
4129 return PTR_ERR(trans);
4131 ret = do_chunk_alloc(trans, alloc_target,
4132 CHUNK_ALLOC_NO_FORCE);
4133 btrfs_end_transaction(trans);
4138 have_pinned_space = 1;
4147 * If we don't have enough pinned space to deal with this
4148 * allocation, and no removed chunk in current transaction,
4149 * don't bother committing the transaction.
4151 have_pinned_space = __percpu_counter_compare(
4152 &data_sinfo->total_bytes_pinned,
4153 used + bytes - data_sinfo->total_bytes,
4154 BTRFS_TOTAL_BYTES_PINNED_BATCH);
4155 spin_unlock(&data_sinfo->lock);
4157 /* commit the current transaction and try again */
4162 if (need_commit > 0) {
4163 btrfs_start_delalloc_roots(fs_info, -1);
4164 btrfs_wait_ordered_roots(fs_info, U64_MAX, 0,
4168 trans = btrfs_join_transaction(root);
4170 return PTR_ERR(trans);
4171 if (have_pinned_space >= 0 ||
4172 test_bit(BTRFS_TRANS_HAVE_FREE_BGS,
4173 &trans->transaction->flags) ||
4175 ret = btrfs_commit_transaction(trans);
4179 * The cleaner kthread might still be doing iput
4180 * operations. Wait for it to finish so that
4181 * more space is released. We don't need to
4182 * explicitly run the delayed iputs here because
4183 * the commit_transaction would have woken up
4186 ret = btrfs_wait_on_delayed_iputs(fs_info);
4191 btrfs_end_transaction(trans);
4195 trace_btrfs_space_reservation(fs_info,
4196 "space_info:enospc",
4197 data_sinfo->flags, bytes, 1);
4200 update_bytes_may_use(data_sinfo, bytes);
4201 trace_btrfs_space_reservation(fs_info, "space_info",
4202 data_sinfo->flags, bytes, 1);
4203 spin_unlock(&data_sinfo->lock);
4208 int btrfs_check_data_free_space(struct inode *inode,
4209 struct extent_changeset **reserved, u64 start, u64 len)
4211 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4214 /* align the range */
4215 len = round_up(start + len, fs_info->sectorsize) -
4216 round_down(start, fs_info->sectorsize);
4217 start = round_down(start, fs_info->sectorsize);
4219 ret = btrfs_alloc_data_chunk_ondemand(BTRFS_I(inode), len);
4223 /* Use new btrfs_qgroup_reserve_data to reserve precious data space. */
4224 ret = btrfs_qgroup_reserve_data(inode, reserved, start, len);
4226 btrfs_free_reserved_data_space_noquota(inode, start, len);
4233 * Called if we need to clear a data reservation for this inode
4234 * Normally in a error case.
4236 * This one will *NOT* use accurate qgroup reserved space API, just for case
4237 * which we can't sleep and is sure it won't affect qgroup reserved space.
4238 * Like clear_bit_hook().
4240 void btrfs_free_reserved_data_space_noquota(struct inode *inode, u64 start,
4243 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4244 struct btrfs_space_info *data_sinfo;
4246 /* Make sure the range is aligned to sectorsize */
4247 len = round_up(start + len, fs_info->sectorsize) -
4248 round_down(start, fs_info->sectorsize);
4249 start = round_down(start, fs_info->sectorsize);
4251 data_sinfo = fs_info->data_sinfo;
4252 spin_lock(&data_sinfo->lock);
4253 update_bytes_may_use(data_sinfo, -len);
4254 trace_btrfs_space_reservation(fs_info, "space_info",
4255 data_sinfo->flags, len, 0);
4256 spin_unlock(&data_sinfo->lock);
4260 * Called if we need to clear a data reservation for this inode
4261 * Normally in a error case.
4263 * This one will handle the per-inode data rsv map for accurate reserved
4266 void btrfs_free_reserved_data_space(struct inode *inode,
4267 struct extent_changeset *reserved, u64 start, u64 len)
4269 struct btrfs_root *root = BTRFS_I(inode)->root;
4271 /* Make sure the range is aligned to sectorsize */
4272 len = round_up(start + len, root->fs_info->sectorsize) -
4273 round_down(start, root->fs_info->sectorsize);
4274 start = round_down(start, root->fs_info->sectorsize);
4276 btrfs_free_reserved_data_space_noquota(inode, start, len);
4277 btrfs_qgroup_free_data(inode, reserved, start, len);
4280 static void force_metadata_allocation(struct btrfs_fs_info *info)
4282 struct list_head *head = &info->space_info;
4283 struct btrfs_space_info *found;
4286 list_for_each_entry_rcu(found, head, list) {
4287 if (found->flags & BTRFS_BLOCK_GROUP_METADATA)
4288 found->force_alloc = CHUNK_ALLOC_FORCE;
4293 static inline u64 calc_global_rsv_need_space(struct btrfs_block_rsv *global)
4295 return (global->size << 1);
4298 static int should_alloc_chunk(struct btrfs_fs_info *fs_info,
4299 struct btrfs_space_info *sinfo, int force)
4301 u64 bytes_used = btrfs_space_info_used(sinfo, false);
4304 if (force == CHUNK_ALLOC_FORCE)
4308 * in limited mode, we want to have some free space up to
4309 * about 1% of the FS size.
4311 if (force == CHUNK_ALLOC_LIMITED) {
4312 thresh = btrfs_super_total_bytes(fs_info->super_copy);
4313 thresh = max_t(u64, SZ_64M, div_factor_fine(thresh, 1));
4315 if (sinfo->total_bytes - bytes_used < thresh)
4319 if (bytes_used + SZ_2M < div_factor(sinfo->total_bytes, 8))
4324 static u64 get_profile_num_devs(struct btrfs_fs_info *fs_info, u64 type)
4328 if (type & (BTRFS_BLOCK_GROUP_RAID10 |
4329 BTRFS_BLOCK_GROUP_RAID0 |
4330 BTRFS_BLOCK_GROUP_RAID5 |
4331 BTRFS_BLOCK_GROUP_RAID6))
4332 num_dev = fs_info->fs_devices->rw_devices;
4333 else if (type & BTRFS_BLOCK_GROUP_RAID1)
4336 num_dev = 1; /* DUP or single */
4342 * If @is_allocation is true, reserve space in the system space info necessary
4343 * for allocating a chunk, otherwise if it's false, reserve space necessary for
4346 void check_system_chunk(struct btrfs_trans_handle *trans, u64 type)
4348 struct btrfs_fs_info *fs_info = trans->fs_info;
4349 struct btrfs_space_info *info;
4356 * Needed because we can end up allocating a system chunk and for an
4357 * atomic and race free space reservation in the chunk block reserve.
4359 lockdep_assert_held(&fs_info->chunk_mutex);
4361 info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
4362 spin_lock(&info->lock);
4363 left = info->total_bytes - btrfs_space_info_used(info, true);
4364 spin_unlock(&info->lock);
4366 num_devs = get_profile_num_devs(fs_info, type);
4368 /* num_devs device items to update and 1 chunk item to add or remove */
4369 thresh = btrfs_calc_trunc_metadata_size(fs_info, num_devs) +
4370 btrfs_calc_trans_metadata_size(fs_info, 1);
4372 if (left < thresh && btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
4373 btrfs_info(fs_info, "left=%llu, need=%llu, flags=%llu",
4374 left, thresh, type);
4375 dump_space_info(fs_info, info, 0, 0);
4378 if (left < thresh) {
4379 u64 flags = btrfs_system_alloc_profile(fs_info);
4382 * Ignore failure to create system chunk. We might end up not
4383 * needing it, as we might not need to COW all nodes/leafs from
4384 * the paths we visit in the chunk tree (they were already COWed
4385 * or created in the current transaction for example).
4387 ret = btrfs_alloc_chunk(trans, flags);
4391 ret = btrfs_block_rsv_add(fs_info->chunk_root,
4392 &fs_info->chunk_block_rsv,
4393 thresh, BTRFS_RESERVE_NO_FLUSH);
4395 trans->chunk_bytes_reserved += thresh;
4400 * If force is CHUNK_ALLOC_FORCE:
4401 * - return 1 if it successfully allocates a chunk,
4402 * - return errors including -ENOSPC otherwise.
4403 * If force is NOT CHUNK_ALLOC_FORCE:
4404 * - return 0 if it doesn't need to allocate a new chunk,
4405 * - return 1 if it successfully allocates a chunk,
4406 * - return errors including -ENOSPC otherwise.
4408 static int do_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
4411 struct btrfs_fs_info *fs_info = trans->fs_info;
4412 struct btrfs_space_info *space_info;
4413 bool wait_for_alloc = false;
4414 bool should_alloc = false;
4417 /* Don't re-enter if we're already allocating a chunk */
4418 if (trans->allocating_chunk)
4421 space_info = __find_space_info(fs_info, flags);
4425 spin_lock(&space_info->lock);
4426 if (force < space_info->force_alloc)
4427 force = space_info->force_alloc;
4428 should_alloc = should_alloc_chunk(fs_info, space_info, force);
4429 if (space_info->full) {
4430 /* No more free physical space */
4435 spin_unlock(&space_info->lock);
4437 } else if (!should_alloc) {
4438 spin_unlock(&space_info->lock);
4440 } else if (space_info->chunk_alloc) {
4442 * Someone is already allocating, so we need to block
4443 * until this someone is finished and then loop to
4444 * recheck if we should continue with our allocation
4447 wait_for_alloc = true;
4448 spin_unlock(&space_info->lock);
4449 mutex_lock(&fs_info->chunk_mutex);
4450 mutex_unlock(&fs_info->chunk_mutex);
4452 /* Proceed with allocation */
4453 space_info->chunk_alloc = 1;
4454 wait_for_alloc = false;
4455 spin_unlock(&space_info->lock);
4459 } while (wait_for_alloc);
4461 mutex_lock(&fs_info->chunk_mutex);
4462 trans->allocating_chunk = true;
4465 * If we have mixed data/metadata chunks we want to make sure we keep
4466 * allocating mixed chunks instead of individual chunks.
4468 if (btrfs_mixed_space_info(space_info))
4469 flags |= (BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA);
4472 * if we're doing a data chunk, go ahead and make sure that
4473 * we keep a reasonable number of metadata chunks allocated in the
4476 if (flags & BTRFS_BLOCK_GROUP_DATA && fs_info->metadata_ratio) {
4477 fs_info->data_chunk_allocations++;
4478 if (!(fs_info->data_chunk_allocations %
4479 fs_info->metadata_ratio))
4480 force_metadata_allocation(fs_info);
4484 * Check if we have enough space in SYSTEM chunk because we may need
4485 * to update devices.
4487 check_system_chunk(trans, flags);
4489 ret = btrfs_alloc_chunk(trans, flags);
4490 trans->allocating_chunk = false;
4492 spin_lock(&space_info->lock);
4495 space_info->full = 1;
4500 space_info->max_extent_size = 0;
4503 space_info->force_alloc = CHUNK_ALLOC_NO_FORCE;
4505 space_info->chunk_alloc = 0;
4506 spin_unlock(&space_info->lock);
4507 mutex_unlock(&fs_info->chunk_mutex);
4509 * When we allocate a new chunk we reserve space in the chunk block
4510 * reserve to make sure we can COW nodes/leafs in the chunk tree or
4511 * add new nodes/leafs to it if we end up needing to do it when
4512 * inserting the chunk item and updating device items as part of the
4513 * second phase of chunk allocation, performed by
4514 * btrfs_finish_chunk_alloc(). So make sure we don't accumulate a
4515 * large number of new block groups to create in our transaction
4516 * handle's new_bgs list to avoid exhausting the chunk block reserve
4517 * in extreme cases - like having a single transaction create many new
4518 * block groups when starting to write out the free space caches of all
4519 * the block groups that were made dirty during the lifetime of the
4522 if (trans->chunk_bytes_reserved >= (u64)SZ_2M)
4523 btrfs_create_pending_block_groups(trans);
4528 static int can_overcommit(struct btrfs_fs_info *fs_info,
4529 struct btrfs_space_info *space_info, u64 bytes,
4530 enum btrfs_reserve_flush_enum flush,
4533 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
4540 /* Don't overcommit when in mixed mode. */
4541 if (space_info->flags & BTRFS_BLOCK_GROUP_DATA)
4545 profile = btrfs_system_alloc_profile(fs_info);
4547 profile = btrfs_metadata_alloc_profile(fs_info);
4549 used = btrfs_space_info_used(space_info, false);
4552 * We only want to allow over committing if we have lots of actual space
4553 * free, but if we don't have enough space to handle the global reserve
4554 * space then we could end up having a real enospc problem when trying
4555 * to allocate a chunk or some other such important allocation.
4557 spin_lock(&global_rsv->lock);
4558 space_size = calc_global_rsv_need_space(global_rsv);
4559 spin_unlock(&global_rsv->lock);
4560 if (used + space_size >= space_info->total_bytes)
4563 used += space_info->bytes_may_use;
4565 avail = atomic64_read(&fs_info->free_chunk_space);
4568 * If we have dup, raid1 or raid10 then only half of the free
4569 * space is actually usable. For raid56, the space info used
4570 * doesn't include the parity drive, so we don't have to
4573 factor = btrfs_bg_type_to_factor(profile);
4574 avail = div_u64(avail, factor);
4577 * If we aren't flushing all things, let us overcommit up to
4578 * 1/2th of the space. If we can flush, don't let us overcommit
4579 * too much, let it overcommit up to 1/8 of the space.
4581 if (flush == BTRFS_RESERVE_FLUSH_ALL)
4586 if (used + bytes < space_info->total_bytes + avail)
4591 static void btrfs_writeback_inodes_sb_nr(struct btrfs_fs_info *fs_info,
4592 unsigned long nr_pages, int nr_items)
4594 struct super_block *sb = fs_info->sb;
4596 if (down_read_trylock(&sb->s_umount)) {
4597 writeback_inodes_sb_nr(sb, nr_pages, WB_REASON_FS_FREE_SPACE);
4598 up_read(&sb->s_umount);
4601 * We needn't worry the filesystem going from r/w to r/o though
4602 * we don't acquire ->s_umount mutex, because the filesystem
4603 * should guarantee the delalloc inodes list be empty after
4604 * the filesystem is readonly(all dirty pages are written to
4607 btrfs_start_delalloc_roots(fs_info, nr_items);
4608 if (!current->journal_info)
4609 btrfs_wait_ordered_roots(fs_info, nr_items, 0, (u64)-1);
4613 static inline u64 calc_reclaim_items_nr(struct btrfs_fs_info *fs_info,
4619 bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
4620 nr = div64_u64(to_reclaim, bytes);
4626 #define EXTENT_SIZE_PER_ITEM SZ_256K
4629 * shrink metadata reservation for delalloc
4631 static void shrink_delalloc(struct btrfs_fs_info *fs_info, u64 to_reclaim,
4632 u64 orig, bool wait_ordered)
4634 struct btrfs_space_info *space_info;
4635 struct btrfs_trans_handle *trans;
4641 unsigned long nr_pages;
4644 /* Calc the number of the pages we need flush for space reservation */
4645 items = calc_reclaim_items_nr(fs_info, to_reclaim);
4646 to_reclaim = items * EXTENT_SIZE_PER_ITEM;
4648 trans = (struct btrfs_trans_handle *)current->journal_info;
4649 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
4651 delalloc_bytes = percpu_counter_sum_positive(
4652 &fs_info->delalloc_bytes);
4653 dio_bytes = percpu_counter_sum_positive(&fs_info->dio_bytes);
4654 if (delalloc_bytes == 0 && dio_bytes == 0) {
4658 btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1);
4663 * If we are doing more ordered than delalloc we need to just wait on
4664 * ordered extents, otherwise we'll waste time trying to flush delalloc
4665 * that likely won't give us the space back we need.
4667 if (dio_bytes > delalloc_bytes)
4668 wait_ordered = true;
4671 while ((delalloc_bytes || dio_bytes) && loops < 3) {
4672 nr_pages = min(delalloc_bytes, to_reclaim) >> PAGE_SHIFT;
4675 * Triggers inode writeback for up to nr_pages. This will invoke
4676 * ->writepages callback and trigger delalloc filling
4677 * (btrfs_run_delalloc_range()).
4679 btrfs_writeback_inodes_sb_nr(fs_info, nr_pages, items);
4682 * We need to wait for the compressed pages to start before
4685 async_pages = atomic_read(&fs_info->async_delalloc_pages);
4690 * Calculate how many compressed pages we want to be written
4691 * before we continue. I.e if there are more async pages than we
4692 * require wait_event will wait until nr_pages are written.
4694 if (async_pages <= nr_pages)
4697 async_pages -= nr_pages;
4699 wait_event(fs_info->async_submit_wait,
4700 atomic_read(&fs_info->async_delalloc_pages) <=
4703 spin_lock(&space_info->lock);
4704 if (list_empty(&space_info->tickets) &&
4705 list_empty(&space_info->priority_tickets)) {
4706 spin_unlock(&space_info->lock);
4709 spin_unlock(&space_info->lock);
4712 if (wait_ordered && !trans) {
4713 btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1);
4715 time_left = schedule_timeout_killable(1);
4719 delalloc_bytes = percpu_counter_sum_positive(
4720 &fs_info->delalloc_bytes);
4721 dio_bytes = percpu_counter_sum_positive(&fs_info->dio_bytes);
4725 struct reserve_ticket {
4729 struct list_head list;
4730 wait_queue_head_t wait;
4734 * maybe_commit_transaction - possibly commit the transaction if its ok to
4735 * @root - the root we're allocating for
4736 * @bytes - the number of bytes we want to reserve
4737 * @force - force the commit
4739 * This will check to make sure that committing the transaction will actually
4740 * get us somewhere and then commit the transaction if it does. Otherwise it
4741 * will return -ENOSPC.
4743 static int may_commit_transaction(struct btrfs_fs_info *fs_info,
4744 struct btrfs_space_info *space_info)
4746 struct reserve_ticket *ticket = NULL;
4747 struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_block_rsv;
4748 struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
4749 struct btrfs_trans_handle *trans;
4751 u64 reclaim_bytes = 0;
4753 trans = (struct btrfs_trans_handle *)current->journal_info;
4757 spin_lock(&space_info->lock);
4758 if (!list_empty(&space_info->priority_tickets))
4759 ticket = list_first_entry(&space_info->priority_tickets,
4760 struct reserve_ticket, list);
4761 else if (!list_empty(&space_info->tickets))
4762 ticket = list_first_entry(&space_info->tickets,
4763 struct reserve_ticket, list);
4764 bytes_needed = (ticket) ? ticket->bytes : 0;
4765 spin_unlock(&space_info->lock);
4770 trans = btrfs_join_transaction(fs_info->extent_root);
4772 return PTR_ERR(trans);
4775 * See if there is enough pinned space to make this reservation, or if
4776 * we have block groups that are going to be freed, allowing us to
4777 * possibly do a chunk allocation the next loop through.
4779 if (test_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags) ||
4780 __percpu_counter_compare(&space_info->total_bytes_pinned,
4782 BTRFS_TOTAL_BYTES_PINNED_BATCH) >= 0)
4786 * See if there is some space in the delayed insertion reservation for
4789 if (space_info != delayed_rsv->space_info)
4792 spin_lock(&delayed_rsv->lock);
4793 reclaim_bytes += delayed_rsv->reserved;
4794 spin_unlock(&delayed_rsv->lock);
4796 spin_lock(&delayed_refs_rsv->lock);
4797 reclaim_bytes += delayed_refs_rsv->reserved;
4798 spin_unlock(&delayed_refs_rsv->lock);
4799 if (reclaim_bytes >= bytes_needed)
4801 bytes_needed -= reclaim_bytes;
4803 if (__percpu_counter_compare(&space_info->total_bytes_pinned,
4805 BTRFS_TOTAL_BYTES_PINNED_BATCH) < 0)
4809 return btrfs_commit_transaction(trans);
4811 btrfs_end_transaction(trans);
4816 * Try to flush some data based on policy set by @state. This is only advisory
4817 * and may fail for various reasons. The caller is supposed to examine the
4818 * state of @space_info to detect the outcome.
4820 static void flush_space(struct btrfs_fs_info *fs_info,
4821 struct btrfs_space_info *space_info, u64 num_bytes,
4824 struct btrfs_root *root = fs_info->extent_root;
4825 struct btrfs_trans_handle *trans;
4830 case FLUSH_DELAYED_ITEMS_NR:
4831 case FLUSH_DELAYED_ITEMS:
4832 if (state == FLUSH_DELAYED_ITEMS_NR)
4833 nr = calc_reclaim_items_nr(fs_info, num_bytes) * 2;
4837 trans = btrfs_join_transaction(root);
4838 if (IS_ERR(trans)) {
4839 ret = PTR_ERR(trans);
4842 ret = btrfs_run_delayed_items_nr(trans, nr);
4843 btrfs_end_transaction(trans);
4845 case FLUSH_DELALLOC:
4846 case FLUSH_DELALLOC_WAIT:
4847 shrink_delalloc(fs_info, num_bytes * 2, num_bytes,
4848 state == FLUSH_DELALLOC_WAIT);
4850 case FLUSH_DELAYED_REFS_NR:
4851 case FLUSH_DELAYED_REFS:
4852 trans = btrfs_join_transaction(root);
4853 if (IS_ERR(trans)) {
4854 ret = PTR_ERR(trans);
4857 if (state == FLUSH_DELAYED_REFS_NR)
4858 nr = calc_reclaim_items_nr(fs_info, num_bytes);
4861 btrfs_run_delayed_refs(trans, nr);
4862 btrfs_end_transaction(trans);
4865 case ALLOC_CHUNK_FORCE:
4866 trans = btrfs_join_transaction(root);
4867 if (IS_ERR(trans)) {
4868 ret = PTR_ERR(trans);
4871 ret = do_chunk_alloc(trans,
4872 btrfs_metadata_alloc_profile(fs_info),
4873 (state == ALLOC_CHUNK) ?
4874 CHUNK_ALLOC_NO_FORCE : CHUNK_ALLOC_FORCE);
4875 btrfs_end_transaction(trans);
4876 if (ret > 0 || ret == -ENOSPC)
4881 * If we have pending delayed iputs then we could free up a
4882 * bunch of pinned space, so make sure we run the iputs before
4883 * we do our pinned bytes check below.
4885 btrfs_run_delayed_iputs(fs_info);
4886 btrfs_wait_on_delayed_iputs(fs_info);
4888 ret = may_commit_transaction(fs_info, space_info);
4895 trace_btrfs_flush_space(fs_info, space_info->flags, num_bytes, state,
4901 btrfs_calc_reclaim_metadata_size(struct btrfs_fs_info *fs_info,
4902 struct btrfs_space_info *space_info,
4905 struct reserve_ticket *ticket;
4910 list_for_each_entry(ticket, &space_info->tickets, list)
4911 to_reclaim += ticket->bytes;
4912 list_for_each_entry(ticket, &space_info->priority_tickets, list)
4913 to_reclaim += ticket->bytes;
4917 to_reclaim = min_t(u64, num_online_cpus() * SZ_1M, SZ_16M);
4918 if (can_overcommit(fs_info, space_info, to_reclaim,
4919 BTRFS_RESERVE_FLUSH_ALL, system_chunk))
4922 used = btrfs_space_info_used(space_info, true);
4924 if (can_overcommit(fs_info, space_info, SZ_1M,
4925 BTRFS_RESERVE_FLUSH_ALL, system_chunk))
4926 expected = div_factor_fine(space_info->total_bytes, 95);
4928 expected = div_factor_fine(space_info->total_bytes, 90);
4930 if (used > expected)
4931 to_reclaim = used - expected;
4934 to_reclaim = min(to_reclaim, space_info->bytes_may_use +
4935 space_info->bytes_reserved);
4939 static inline int need_do_async_reclaim(struct btrfs_fs_info *fs_info,
4940 struct btrfs_space_info *space_info,
4941 u64 used, bool system_chunk)
4943 u64 thresh = div_factor_fine(space_info->total_bytes, 98);
4945 /* If we're just plain full then async reclaim just slows us down. */
4946 if ((space_info->bytes_used + space_info->bytes_reserved) >= thresh)
4949 if (!btrfs_calc_reclaim_metadata_size(fs_info, space_info,
4953 return (used >= thresh && !btrfs_fs_closing(fs_info) &&
4954 !test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state));
4957 static bool wake_all_tickets(struct list_head *head)
4959 struct reserve_ticket *ticket;
4961 while (!list_empty(head)) {
4962 ticket = list_first_entry(head, struct reserve_ticket, list);
4963 list_del_init(&ticket->list);
4964 ticket->error = -ENOSPC;
4965 wake_up(&ticket->wait);
4966 if (ticket->bytes != ticket->orig_bytes)
4973 * This is for normal flushers, we can wait all goddamned day if we want to. We
4974 * will loop and continuously try to flush as long as we are making progress.
4975 * We count progress as clearing off tickets each time we have to loop.
4977 static void btrfs_async_reclaim_metadata_space(struct work_struct *work)
4979 struct btrfs_fs_info *fs_info;
4980 struct btrfs_space_info *space_info;
4983 int commit_cycles = 0;
4984 u64 last_tickets_id;
4986 fs_info = container_of(work, struct btrfs_fs_info, async_reclaim_work);
4987 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
4989 spin_lock(&space_info->lock);
4990 to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info,
4993 space_info->flush = 0;
4994 spin_unlock(&space_info->lock);
4997 last_tickets_id = space_info->tickets_id;
4998 spin_unlock(&space_info->lock);
5000 flush_state = FLUSH_DELAYED_ITEMS_NR;
5002 flush_space(fs_info, space_info, to_reclaim, flush_state);
5003 spin_lock(&space_info->lock);
5004 if (list_empty(&space_info->tickets)) {
5005 space_info->flush = 0;
5006 spin_unlock(&space_info->lock);
5009 to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info,
5012 if (last_tickets_id == space_info->tickets_id) {
5015 last_tickets_id = space_info->tickets_id;
5016 flush_state = FLUSH_DELAYED_ITEMS_NR;
5022 * We don't want to force a chunk allocation until we've tried
5023 * pretty hard to reclaim space. Think of the case where we
5024 * freed up a bunch of space and so have a lot of pinned space
5025 * to reclaim. We would rather use that than possibly create a
5026 * underutilized metadata chunk. So if this is our first run
5027 * through the flushing state machine skip ALLOC_CHUNK_FORCE and
5028 * commit the transaction. If nothing has changed the next go
5029 * around then we can force a chunk allocation.
5031 if (flush_state == ALLOC_CHUNK_FORCE && !commit_cycles)
5034 if (flush_state > COMMIT_TRANS) {
5036 if (commit_cycles > 2) {
5037 if (wake_all_tickets(&space_info->tickets)) {
5038 flush_state = FLUSH_DELAYED_ITEMS_NR;
5041 space_info->flush = 0;
5044 flush_state = FLUSH_DELAYED_ITEMS_NR;
5047 spin_unlock(&space_info->lock);
5048 } while (flush_state <= COMMIT_TRANS);
5051 void btrfs_init_async_reclaim_work(struct work_struct *work)
5053 INIT_WORK(work, btrfs_async_reclaim_metadata_space);
5056 static const enum btrfs_flush_state priority_flush_states[] = {
5057 FLUSH_DELAYED_ITEMS_NR,
5058 FLUSH_DELAYED_ITEMS,
5062 static void priority_reclaim_metadata_space(struct btrfs_fs_info *fs_info,
5063 struct btrfs_space_info *space_info,
5064 struct reserve_ticket *ticket)
5069 spin_lock(&space_info->lock);
5070 to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info,
5073 spin_unlock(&space_info->lock);
5076 spin_unlock(&space_info->lock);
5080 flush_space(fs_info, space_info, to_reclaim,
5081 priority_flush_states[flush_state]);
5083 spin_lock(&space_info->lock);
5084 if (ticket->bytes == 0) {
5085 spin_unlock(&space_info->lock);
5088 spin_unlock(&space_info->lock);
5089 } while (flush_state < ARRAY_SIZE(priority_flush_states));
5092 static int wait_reserve_ticket(struct btrfs_fs_info *fs_info,
5093 struct btrfs_space_info *space_info,
5094 struct reserve_ticket *ticket)
5098 u64 reclaim_bytes = 0;
5101 spin_lock(&space_info->lock);
5102 while (ticket->bytes > 0 && ticket->error == 0) {
5103 ret = prepare_to_wait_event(&ticket->wait, &wait, TASK_KILLABLE);
5108 spin_unlock(&space_info->lock);
5112 finish_wait(&ticket->wait, &wait);
5113 spin_lock(&space_info->lock);
5116 ret = ticket->error;
5117 if (!list_empty(&ticket->list))
5118 list_del_init(&ticket->list);
5119 if (ticket->bytes && ticket->bytes < ticket->orig_bytes)
5120 reclaim_bytes = ticket->orig_bytes - ticket->bytes;
5121 spin_unlock(&space_info->lock);
5124 space_info_add_old_bytes(fs_info, space_info, reclaim_bytes);
5129 * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
5130 * @root - the root we're allocating for
5131 * @space_info - the space info we want to allocate from
5132 * @orig_bytes - the number of bytes we want
5133 * @flush - whether or not we can flush to make our reservation
5135 * This will reserve orig_bytes number of bytes from the space info associated
5136 * with the block_rsv. If there is not enough space it will make an attempt to
5137 * flush out space to make room. It will do this by flushing delalloc if
5138 * possible or committing the transaction. If flush is 0 then no attempts to
5139 * regain reservations will be made and this will fail if there is not enough
5142 static int __reserve_metadata_bytes(struct btrfs_fs_info *fs_info,
5143 struct btrfs_space_info *space_info,
5145 enum btrfs_reserve_flush_enum flush,
5148 struct reserve_ticket ticket;
5150 u64 reclaim_bytes = 0;
5154 ASSERT(!current->journal_info || flush != BTRFS_RESERVE_FLUSH_ALL);
5156 spin_lock(&space_info->lock);
5158 used = btrfs_space_info_used(space_info, true);
5161 * If we have enough space then hooray, make our reservation and carry
5162 * on. If not see if we can overcommit, and if we can, hooray carry on.
5163 * If not things get more complicated.
5165 if (used + orig_bytes <= space_info->total_bytes) {
5166 update_bytes_may_use(space_info, orig_bytes);
5167 trace_btrfs_space_reservation(fs_info, "space_info",
5168 space_info->flags, orig_bytes, 1);
5170 } else if (can_overcommit(fs_info, space_info, orig_bytes, flush,
5172 update_bytes_may_use(space_info, orig_bytes);
5173 trace_btrfs_space_reservation(fs_info, "space_info",
5174 space_info->flags, orig_bytes, 1);
5179 * If we couldn't make a reservation then setup our reservation ticket
5180 * and kick the async worker if it's not already running.
5182 * If we are a priority flusher then we just need to add our ticket to
5183 * the list and we will do our own flushing further down.
5185 if (ret && flush != BTRFS_RESERVE_NO_FLUSH) {
5186 ticket.orig_bytes = orig_bytes;
5187 ticket.bytes = orig_bytes;
5189 init_waitqueue_head(&ticket.wait);
5190 if (flush == BTRFS_RESERVE_FLUSH_ALL) {
5191 list_add_tail(&ticket.list, &space_info->tickets);
5192 if (!space_info->flush) {
5193 space_info->flush = 1;
5194 trace_btrfs_trigger_flush(fs_info,
5198 queue_work(system_unbound_wq,
5199 &fs_info->async_reclaim_work);
5202 list_add_tail(&ticket.list,
5203 &space_info->priority_tickets);
5205 } else if (!ret && space_info->flags & BTRFS_BLOCK_GROUP_METADATA) {
5208 * We will do the space reservation dance during log replay,
5209 * which means we won't have fs_info->fs_root set, so don't do
5210 * the async reclaim as we will panic.
5212 if (!test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags) &&
5213 need_do_async_reclaim(fs_info, space_info,
5214 used, system_chunk) &&
5215 !work_busy(&fs_info->async_reclaim_work)) {
5216 trace_btrfs_trigger_flush(fs_info, space_info->flags,
5217 orig_bytes, flush, "preempt");
5218 queue_work(system_unbound_wq,
5219 &fs_info->async_reclaim_work);
5222 spin_unlock(&space_info->lock);
5223 if (!ret || flush == BTRFS_RESERVE_NO_FLUSH)
5226 if (flush == BTRFS_RESERVE_FLUSH_ALL)
5227 return wait_reserve_ticket(fs_info, space_info, &ticket);
5230 priority_reclaim_metadata_space(fs_info, space_info, &ticket);
5231 spin_lock(&space_info->lock);
5233 if (ticket.bytes < orig_bytes)
5234 reclaim_bytes = orig_bytes - ticket.bytes;
5235 list_del_init(&ticket.list);
5238 spin_unlock(&space_info->lock);
5241 space_info_add_old_bytes(fs_info, space_info, reclaim_bytes);
5242 ASSERT(list_empty(&ticket.list));
5247 * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
5248 * @root - the root we're allocating for
5249 * @block_rsv - the block_rsv we're allocating for
5250 * @orig_bytes - the number of bytes we want
5251 * @flush - whether or not we can flush to make our reservation
5253 * This will reserve orig_bytes number of bytes from the space info associated
5254 * with the block_rsv. If there is not enough space it will make an attempt to
5255 * flush out space to make room. It will do this by flushing delalloc if
5256 * possible or committing the transaction. If flush is 0 then no attempts to
5257 * regain reservations will be made and this will fail if there is not enough
5260 static int reserve_metadata_bytes(struct btrfs_root *root,
5261 struct btrfs_block_rsv *block_rsv,
5263 enum btrfs_reserve_flush_enum flush)
5265 struct btrfs_fs_info *fs_info = root->fs_info;
5266 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
5268 bool system_chunk = (root == fs_info->chunk_root);
5270 ret = __reserve_metadata_bytes(fs_info, block_rsv->space_info,
5271 orig_bytes, flush, system_chunk);
5272 if (ret == -ENOSPC &&
5273 unlikely(root->orphan_cleanup_state == ORPHAN_CLEANUP_STARTED)) {
5274 if (block_rsv != global_rsv &&
5275 !block_rsv_use_bytes(global_rsv, orig_bytes))
5278 if (ret == -ENOSPC) {
5279 trace_btrfs_space_reservation(fs_info, "space_info:enospc",
5280 block_rsv->space_info->flags,
5283 if (btrfs_test_opt(fs_info, ENOSPC_DEBUG))
5284 dump_space_info(fs_info, block_rsv->space_info,
5290 static struct btrfs_block_rsv *get_block_rsv(
5291 const struct btrfs_trans_handle *trans,
5292 const struct btrfs_root *root)
5294 struct btrfs_fs_info *fs_info = root->fs_info;
5295 struct btrfs_block_rsv *block_rsv = NULL;
5297 if (test_bit(BTRFS_ROOT_REF_COWS, &root->state) ||
5298 (root == fs_info->csum_root && trans->adding_csums) ||
5299 (root == fs_info->uuid_root))
5300 block_rsv = trans->block_rsv;
5303 block_rsv = root->block_rsv;
5306 block_rsv = &fs_info->empty_block_rsv;
5311 static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
5315 spin_lock(&block_rsv->lock);
5316 if (block_rsv->reserved >= num_bytes) {
5317 block_rsv->reserved -= num_bytes;
5318 if (block_rsv->reserved < block_rsv->size)
5319 block_rsv->full = 0;
5322 spin_unlock(&block_rsv->lock);
5326 static void block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
5327 u64 num_bytes, bool update_size)
5329 spin_lock(&block_rsv->lock);
5330 block_rsv->reserved += num_bytes;
5332 block_rsv->size += num_bytes;
5333 else if (block_rsv->reserved >= block_rsv->size)
5334 block_rsv->full = 1;
5335 spin_unlock(&block_rsv->lock);
5338 int btrfs_cond_migrate_bytes(struct btrfs_fs_info *fs_info,
5339 struct btrfs_block_rsv *dest, u64 num_bytes,
5342 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
5345 if (global_rsv->space_info != dest->space_info)
5348 spin_lock(&global_rsv->lock);
5349 min_bytes = div_factor(global_rsv->size, min_factor);
5350 if (global_rsv->reserved < min_bytes + num_bytes) {
5351 spin_unlock(&global_rsv->lock);
5354 global_rsv->reserved -= num_bytes;
5355 if (global_rsv->reserved < global_rsv->size)
5356 global_rsv->full = 0;
5357 spin_unlock(&global_rsv->lock);
5359 block_rsv_add_bytes(dest, num_bytes, true);
5364 * btrfs_migrate_to_delayed_refs_rsv - transfer bytes to our delayed refs rsv.
5365 * @fs_info - the fs info for our fs.
5366 * @src - the source block rsv to transfer from.
5367 * @num_bytes - the number of bytes to transfer.
5369 * This transfers up to the num_bytes amount from the src rsv to the
5370 * delayed_refs_rsv. Any extra bytes are returned to the space info.
5372 void btrfs_migrate_to_delayed_refs_rsv(struct btrfs_fs_info *fs_info,
5373 struct btrfs_block_rsv *src,
5376 struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
5379 spin_lock(&src->lock);
5380 src->reserved -= num_bytes;
5381 src->size -= num_bytes;
5382 spin_unlock(&src->lock);
5384 spin_lock(&delayed_refs_rsv->lock);
5385 if (delayed_refs_rsv->size > delayed_refs_rsv->reserved) {
5386 u64 delta = delayed_refs_rsv->size -
5387 delayed_refs_rsv->reserved;
5388 if (num_bytes > delta) {
5389 to_free = num_bytes - delta;
5393 to_free = num_bytes;
5398 delayed_refs_rsv->reserved += num_bytes;
5399 if (delayed_refs_rsv->reserved >= delayed_refs_rsv->size)
5400 delayed_refs_rsv->full = 1;
5401 spin_unlock(&delayed_refs_rsv->lock);
5404 trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv",
5407 space_info_add_old_bytes(fs_info, delayed_refs_rsv->space_info,
5412 * btrfs_delayed_refs_rsv_refill - refill based on our delayed refs usage.
5413 * @fs_info - the fs_info for our fs.
5414 * @flush - control how we can flush for this reservation.
5416 * This will refill the delayed block_rsv up to 1 items size worth of space and
5417 * will return -ENOSPC if we can't make the reservation.
5419 int btrfs_delayed_refs_rsv_refill(struct btrfs_fs_info *fs_info,
5420 enum btrfs_reserve_flush_enum flush)
5422 struct btrfs_block_rsv *block_rsv = &fs_info->delayed_refs_rsv;
5423 u64 limit = btrfs_calc_trans_metadata_size(fs_info, 1);
5427 spin_lock(&block_rsv->lock);
5428 if (block_rsv->reserved < block_rsv->size) {
5429 num_bytes = block_rsv->size - block_rsv->reserved;
5430 num_bytes = min(num_bytes, limit);
5432 spin_unlock(&block_rsv->lock);
5437 ret = reserve_metadata_bytes(fs_info->extent_root, block_rsv,
5441 block_rsv_add_bytes(block_rsv, num_bytes, 0);
5442 trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv",
5448 * This is for space we already have accounted in space_info->bytes_may_use, so
5449 * basically when we're returning space from block_rsv's.
5451 static void space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
5452 struct btrfs_space_info *space_info,
5455 struct reserve_ticket *ticket;
5456 struct list_head *head;
5458 enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_NO_FLUSH;
5459 bool check_overcommit = false;
5461 spin_lock(&space_info->lock);
5462 head = &space_info->priority_tickets;
5465 * If we are over our limit then we need to check and see if we can
5466 * overcommit, and if we can't then we just need to free up our space
5467 * and not satisfy any requests.
5469 used = btrfs_space_info_used(space_info, true);
5470 if (used - num_bytes >= space_info->total_bytes)
5471 check_overcommit = true;
5473 while (!list_empty(head) && num_bytes) {
5474 ticket = list_first_entry(head, struct reserve_ticket,
5477 * We use 0 bytes because this space is already reserved, so
5478 * adding the ticket space would be a double count.
5480 if (check_overcommit &&
5481 !can_overcommit(fs_info, space_info, 0, flush, false))
5483 if (num_bytes >= ticket->bytes) {
5484 list_del_init(&ticket->list);
5485 num_bytes -= ticket->bytes;
5487 space_info->tickets_id++;
5488 wake_up(&ticket->wait);
5490 ticket->bytes -= num_bytes;
5495 if (num_bytes && head == &space_info->priority_tickets) {
5496 head = &space_info->tickets;
5497 flush = BTRFS_RESERVE_FLUSH_ALL;
5500 update_bytes_may_use(space_info, -num_bytes);
5501 trace_btrfs_space_reservation(fs_info, "space_info",
5502 space_info->flags, num_bytes, 0);
5503 spin_unlock(&space_info->lock);
5507 * This is for newly allocated space that isn't accounted in
5508 * space_info->bytes_may_use yet. So if we allocate a chunk or unpin an extent
5509 * we use this helper.
5511 static void space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
5512 struct btrfs_space_info *space_info,
5515 struct reserve_ticket *ticket;
5516 struct list_head *head = &space_info->priority_tickets;
5519 while (!list_empty(head) && num_bytes) {
5520 ticket = list_first_entry(head, struct reserve_ticket,
5522 if (num_bytes >= ticket->bytes) {
5523 trace_btrfs_space_reservation(fs_info, "space_info",
5526 list_del_init(&ticket->list);
5527 num_bytes -= ticket->bytes;
5528 update_bytes_may_use(space_info, ticket->bytes);
5530 space_info->tickets_id++;
5531 wake_up(&ticket->wait);
5533 trace_btrfs_space_reservation(fs_info, "space_info",
5536 update_bytes_may_use(space_info, num_bytes);
5537 ticket->bytes -= num_bytes;
5542 if (num_bytes && head == &space_info->priority_tickets) {
5543 head = &space_info->tickets;
5548 static u64 block_rsv_release_bytes(struct btrfs_fs_info *fs_info,
5549 struct btrfs_block_rsv *block_rsv,
5550 struct btrfs_block_rsv *dest, u64 num_bytes,
5551 u64 *qgroup_to_release_ret)
5553 struct btrfs_space_info *space_info = block_rsv->space_info;
5554 u64 qgroup_to_release = 0;
5557 spin_lock(&block_rsv->lock);
5558 if (num_bytes == (u64)-1) {
5559 num_bytes = block_rsv->size;
5560 qgroup_to_release = block_rsv->qgroup_rsv_size;
5562 block_rsv->size -= num_bytes;
5563 if (block_rsv->reserved >= block_rsv->size) {
5564 num_bytes = block_rsv->reserved - block_rsv->size;
5565 block_rsv->reserved = block_rsv->size;
5566 block_rsv->full = 1;
5570 if (block_rsv->qgroup_rsv_reserved >= block_rsv->qgroup_rsv_size) {
5571 qgroup_to_release = block_rsv->qgroup_rsv_reserved -
5572 block_rsv->qgroup_rsv_size;
5573 block_rsv->qgroup_rsv_reserved = block_rsv->qgroup_rsv_size;
5575 qgroup_to_release = 0;
5577 spin_unlock(&block_rsv->lock);
5580 if (num_bytes > 0) {
5582 spin_lock(&dest->lock);
5586 bytes_to_add = dest->size - dest->reserved;
5587 bytes_to_add = min(num_bytes, bytes_to_add);
5588 dest->reserved += bytes_to_add;
5589 if (dest->reserved >= dest->size)
5591 num_bytes -= bytes_to_add;
5593 spin_unlock(&dest->lock);
5596 space_info_add_old_bytes(fs_info, space_info,
5599 if (qgroup_to_release_ret)
5600 *qgroup_to_release_ret = qgroup_to_release;
5604 int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src,
5605 struct btrfs_block_rsv *dst, u64 num_bytes,
5610 ret = block_rsv_use_bytes(src, num_bytes);
5614 block_rsv_add_bytes(dst, num_bytes, update_size);
5618 void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv, unsigned short type)
5620 memset(rsv, 0, sizeof(*rsv));
5621 spin_lock_init(&rsv->lock);
5625 void btrfs_init_metadata_block_rsv(struct btrfs_fs_info *fs_info,
5626 struct btrfs_block_rsv *rsv,
5627 unsigned short type)
5629 btrfs_init_block_rsv(rsv, type);
5630 rsv->space_info = __find_space_info(fs_info,
5631 BTRFS_BLOCK_GROUP_METADATA);
5634 struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_fs_info *fs_info,
5635 unsigned short type)
5637 struct btrfs_block_rsv *block_rsv;
5639 block_rsv = kmalloc(sizeof(*block_rsv), GFP_NOFS);
5643 btrfs_init_metadata_block_rsv(fs_info, block_rsv, type);
5647 void btrfs_free_block_rsv(struct btrfs_fs_info *fs_info,
5648 struct btrfs_block_rsv *rsv)
5652 btrfs_block_rsv_release(fs_info, rsv, (u64)-1);
5656 int btrfs_block_rsv_add(struct btrfs_root *root,
5657 struct btrfs_block_rsv *block_rsv, u64 num_bytes,
5658 enum btrfs_reserve_flush_enum flush)
5665 ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
5667 block_rsv_add_bytes(block_rsv, num_bytes, true);
5672 int btrfs_block_rsv_check(struct btrfs_block_rsv *block_rsv, int min_factor)
5680 spin_lock(&block_rsv->lock);
5681 num_bytes = div_factor(block_rsv->size, min_factor);
5682 if (block_rsv->reserved >= num_bytes)
5684 spin_unlock(&block_rsv->lock);
5689 int btrfs_block_rsv_refill(struct btrfs_root *root,
5690 struct btrfs_block_rsv *block_rsv, u64 min_reserved,
5691 enum btrfs_reserve_flush_enum flush)
5699 spin_lock(&block_rsv->lock);
5700 num_bytes = min_reserved;
5701 if (block_rsv->reserved >= num_bytes)
5704 num_bytes -= block_rsv->reserved;
5705 spin_unlock(&block_rsv->lock);
5710 ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
5712 block_rsv_add_bytes(block_rsv, num_bytes, false);
5719 static u64 __btrfs_block_rsv_release(struct btrfs_fs_info *fs_info,
5720 struct btrfs_block_rsv *block_rsv,
5721 u64 num_bytes, u64 *qgroup_to_release)
5723 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
5724 struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_refs_rsv;
5725 struct btrfs_block_rsv *target = delayed_rsv;
5727 if (target->full || target == block_rsv)
5728 target = global_rsv;
5730 if (block_rsv->space_info != target->space_info)
5733 return block_rsv_release_bytes(fs_info, block_rsv, target, num_bytes,
5737 void btrfs_block_rsv_release(struct btrfs_fs_info *fs_info,
5738 struct btrfs_block_rsv *block_rsv,
5741 __btrfs_block_rsv_release(fs_info, block_rsv, num_bytes, NULL);
5745 * btrfs_inode_rsv_release - release any excessive reservation.
5746 * @inode - the inode we need to release from.
5747 * @qgroup_free - free or convert qgroup meta.
5748 * Unlike normal operation, qgroup meta reservation needs to know if we are
5749 * freeing qgroup reservation or just converting it into per-trans. Normally
5750 * @qgroup_free is true for error handling, and false for normal release.
5752 * This is the same as btrfs_block_rsv_release, except that it handles the
5753 * tracepoint for the reservation.
5755 static void btrfs_inode_rsv_release(struct btrfs_inode *inode, bool qgroup_free)
5757 struct btrfs_fs_info *fs_info = inode->root->fs_info;
5758 struct btrfs_block_rsv *block_rsv = &inode->block_rsv;
5760 u64 qgroup_to_release = 0;
5763 * Since we statically set the block_rsv->size we just want to say we
5764 * are releasing 0 bytes, and then we'll just get the reservation over
5767 released = __btrfs_block_rsv_release(fs_info, block_rsv, 0,
5768 &qgroup_to_release);
5770 trace_btrfs_space_reservation(fs_info, "delalloc",
5771 btrfs_ino(inode), released, 0);
5773 btrfs_qgroup_free_meta_prealloc(inode->root, qgroup_to_release);
5775 btrfs_qgroup_convert_reserved_meta(inode->root,
5780 * btrfs_delayed_refs_rsv_release - release a ref head's reservation.
5781 * @fs_info - the fs_info for our fs.
5782 * @nr - the number of items to drop.
5784 * This drops the delayed ref head's count from the delayed refs rsv and frees
5785 * any excess reservation we had.
5787 void btrfs_delayed_refs_rsv_release(struct btrfs_fs_info *fs_info, int nr)
5789 struct btrfs_block_rsv *block_rsv = &fs_info->delayed_refs_rsv;
5790 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
5791 u64 num_bytes = btrfs_calc_trans_metadata_size(fs_info, nr);
5794 released = block_rsv_release_bytes(fs_info, block_rsv, global_rsv,
5797 trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv",
5801 static void update_global_block_rsv(struct btrfs_fs_info *fs_info)
5803 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
5804 struct btrfs_space_info *sinfo = block_rsv->space_info;
5808 * The global block rsv is based on the size of the extent tree, the
5809 * checksum tree and the root tree. If the fs is empty we want to set
5810 * it to a minimal amount for safety.
5812 num_bytes = btrfs_root_used(&fs_info->extent_root->root_item) +
5813 btrfs_root_used(&fs_info->csum_root->root_item) +
5814 btrfs_root_used(&fs_info->tree_root->root_item);
5815 num_bytes = max_t(u64, num_bytes, SZ_16M);
5817 spin_lock(&sinfo->lock);
5818 spin_lock(&block_rsv->lock);
5820 block_rsv->size = min_t(u64, num_bytes, SZ_512M);
5822 if (block_rsv->reserved < block_rsv->size) {
5823 num_bytes = btrfs_space_info_used(sinfo, true);
5824 if (sinfo->total_bytes > num_bytes) {
5825 num_bytes = sinfo->total_bytes - num_bytes;
5826 num_bytes = min(num_bytes,
5827 block_rsv->size - block_rsv->reserved);
5828 block_rsv->reserved += num_bytes;
5829 update_bytes_may_use(sinfo, num_bytes);
5830 trace_btrfs_space_reservation(fs_info, "space_info",
5831 sinfo->flags, num_bytes,
5834 } else if (block_rsv->reserved > block_rsv->size) {
5835 num_bytes = block_rsv->reserved - block_rsv->size;
5836 update_bytes_may_use(sinfo, -num_bytes);
5837 trace_btrfs_space_reservation(fs_info, "space_info",
5838 sinfo->flags, num_bytes, 0);
5839 block_rsv->reserved = block_rsv->size;
5842 if (block_rsv->reserved == block_rsv->size)
5843 block_rsv->full = 1;
5845 block_rsv->full = 0;
5847 spin_unlock(&block_rsv->lock);
5848 spin_unlock(&sinfo->lock);
5851 static void init_global_block_rsv(struct btrfs_fs_info *fs_info)
5853 struct btrfs_space_info *space_info;
5855 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
5856 fs_info->chunk_block_rsv.space_info = space_info;
5858 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
5859 fs_info->global_block_rsv.space_info = space_info;
5860 fs_info->trans_block_rsv.space_info = space_info;
5861 fs_info->empty_block_rsv.space_info = space_info;
5862 fs_info->delayed_block_rsv.space_info = space_info;
5863 fs_info->delayed_refs_rsv.space_info = space_info;
5865 fs_info->extent_root->block_rsv = &fs_info->delayed_refs_rsv;
5866 fs_info->csum_root->block_rsv = &fs_info->delayed_refs_rsv;
5867 fs_info->dev_root->block_rsv = &fs_info->global_block_rsv;
5868 fs_info->tree_root->block_rsv = &fs_info->global_block_rsv;
5869 if (fs_info->quota_root)
5870 fs_info->quota_root->block_rsv = &fs_info->global_block_rsv;
5871 fs_info->chunk_root->block_rsv = &fs_info->chunk_block_rsv;
5873 update_global_block_rsv(fs_info);
5876 static void release_global_block_rsv(struct btrfs_fs_info *fs_info)
5878 block_rsv_release_bytes(fs_info, &fs_info->global_block_rsv, NULL,
5880 WARN_ON(fs_info->trans_block_rsv.size > 0);
5881 WARN_ON(fs_info->trans_block_rsv.reserved > 0);
5882 WARN_ON(fs_info->chunk_block_rsv.size > 0);
5883 WARN_ON(fs_info->chunk_block_rsv.reserved > 0);
5884 WARN_ON(fs_info->delayed_block_rsv.size > 0);
5885 WARN_ON(fs_info->delayed_block_rsv.reserved > 0);
5886 WARN_ON(fs_info->delayed_refs_rsv.reserved > 0);
5887 WARN_ON(fs_info->delayed_refs_rsv.size > 0);
5891 * btrfs_update_delayed_refs_rsv - adjust the size of the delayed refs rsv
5892 * @trans - the trans that may have generated delayed refs
5894 * This is to be called anytime we may have adjusted trans->delayed_ref_updates,
5895 * it'll calculate the additional size and add it to the delayed_refs_rsv.
5897 void btrfs_update_delayed_refs_rsv(struct btrfs_trans_handle *trans)
5899 struct btrfs_fs_info *fs_info = trans->fs_info;
5900 struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_refs_rsv;
5903 if (!trans->delayed_ref_updates)
5906 num_bytes = btrfs_calc_trans_metadata_size(fs_info,
5907 trans->delayed_ref_updates);
5908 spin_lock(&delayed_rsv->lock);
5909 delayed_rsv->size += num_bytes;
5910 delayed_rsv->full = 0;
5911 spin_unlock(&delayed_rsv->lock);
5912 trans->delayed_ref_updates = 0;
5916 * To be called after all the new block groups attached to the transaction
5917 * handle have been created (btrfs_create_pending_block_groups()).
5919 void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans)
5921 struct btrfs_fs_info *fs_info = trans->fs_info;
5923 if (!trans->chunk_bytes_reserved)
5926 WARN_ON_ONCE(!list_empty(&trans->new_bgs));
5928 block_rsv_release_bytes(fs_info, &fs_info->chunk_block_rsv, NULL,
5929 trans->chunk_bytes_reserved, NULL);
5930 trans->chunk_bytes_reserved = 0;
5934 * btrfs_subvolume_reserve_metadata() - reserve space for subvolume operation
5935 * root: the root of the parent directory
5936 * rsv: block reservation
5937 * items: the number of items that we need do reservation
5938 * use_global_rsv: allow fallback to the global block reservation
5940 * This function is used to reserve the space for snapshot/subvolume
5941 * creation and deletion. Those operations are different with the
5942 * common file/directory operations, they change two fs/file trees
5943 * and root tree, the number of items that the qgroup reserves is
5944 * different with the free space reservation. So we can not use
5945 * the space reservation mechanism in start_transaction().
5947 int btrfs_subvolume_reserve_metadata(struct btrfs_root *root,
5948 struct btrfs_block_rsv *rsv, int items,
5949 bool use_global_rsv)
5951 u64 qgroup_num_bytes = 0;
5954 struct btrfs_fs_info *fs_info = root->fs_info;
5955 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
5957 if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)) {
5958 /* One for parent inode, two for dir entries */
5959 qgroup_num_bytes = 3 * fs_info->nodesize;
5960 ret = btrfs_qgroup_reserve_meta_prealloc(root,
5961 qgroup_num_bytes, true);
5966 num_bytes = btrfs_calc_trans_metadata_size(fs_info, items);
5967 rsv->space_info = __find_space_info(fs_info,
5968 BTRFS_BLOCK_GROUP_METADATA);
5969 ret = btrfs_block_rsv_add(root, rsv, num_bytes,
5970 BTRFS_RESERVE_FLUSH_ALL);
5972 if (ret == -ENOSPC && use_global_rsv)
5973 ret = btrfs_block_rsv_migrate(global_rsv, rsv, num_bytes, true);
5975 if (ret && qgroup_num_bytes)
5976 btrfs_qgroup_free_meta_prealloc(root, qgroup_num_bytes);
5981 void btrfs_subvolume_release_metadata(struct btrfs_fs_info *fs_info,
5982 struct btrfs_block_rsv *rsv)
5984 btrfs_block_rsv_release(fs_info, rsv, (u64)-1);
5987 static void btrfs_calculate_inode_block_rsv_size(struct btrfs_fs_info *fs_info,
5988 struct btrfs_inode *inode)
5990 struct btrfs_block_rsv *block_rsv = &inode->block_rsv;
5991 u64 reserve_size = 0;
5992 u64 qgroup_rsv_size = 0;
5994 unsigned outstanding_extents;
5996 lockdep_assert_held(&inode->lock);
5997 outstanding_extents = inode->outstanding_extents;
5998 if (outstanding_extents)
5999 reserve_size = btrfs_calc_trans_metadata_size(fs_info,
6000 outstanding_extents + 1);
6001 csum_leaves = btrfs_csum_bytes_to_leaves(fs_info,
6003 reserve_size += btrfs_calc_trans_metadata_size(fs_info,
6006 * For qgroup rsv, the calculation is very simple:
6007 * account one nodesize for each outstanding extent
6009 * This is overestimating in most cases.
6011 qgroup_rsv_size = (u64)outstanding_extents * fs_info->nodesize;
6013 spin_lock(&block_rsv->lock);
6014 block_rsv->size = reserve_size;
6015 block_rsv->qgroup_rsv_size = qgroup_rsv_size;
6016 spin_unlock(&block_rsv->lock);
6019 static void calc_inode_reservations(struct btrfs_fs_info *fs_info,
6020 u64 num_bytes, u64 *meta_reserve,
6021 u64 *qgroup_reserve)
6023 u64 nr_extents = count_max_extents(num_bytes);
6024 u64 csum_leaves = btrfs_csum_bytes_to_leaves(fs_info, num_bytes);
6026 /* We add one for the inode update at finish ordered time */
6027 *meta_reserve = btrfs_calc_trans_metadata_size(fs_info,
6028 nr_extents + csum_leaves + 1);
6029 *qgroup_reserve = nr_extents * fs_info->nodesize;
6032 int btrfs_delalloc_reserve_metadata(struct btrfs_inode *inode, u64 num_bytes)
6034 struct btrfs_root *root = inode->root;
6035 struct btrfs_fs_info *fs_info = root->fs_info;
6036 struct btrfs_block_rsv *block_rsv = &inode->block_rsv;
6037 u64 meta_reserve, qgroup_reserve;
6038 unsigned nr_extents;
6039 enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_FLUSH_ALL;
6041 bool delalloc_lock = true;
6043 /* If we are a free space inode we need to not flush since we will be in
6044 * the middle of a transaction commit. We also don't need the delalloc
6045 * mutex since we won't race with anybody. We need this mostly to make
6046 * lockdep shut its filthy mouth.
6048 * If we have a transaction open (can happen if we call truncate_block
6049 * from truncate), then we need FLUSH_LIMIT so we don't deadlock.
6051 if (btrfs_is_free_space_inode(inode)) {
6052 flush = BTRFS_RESERVE_NO_FLUSH;
6053 delalloc_lock = false;
6055 if (current->journal_info)
6056 flush = BTRFS_RESERVE_FLUSH_LIMIT;
6058 if (btrfs_transaction_in_commit(fs_info))
6059 schedule_timeout(1);
6063 mutex_lock(&inode->delalloc_mutex);
6065 num_bytes = ALIGN(num_bytes, fs_info->sectorsize);
6068 * We always want to do it this way, every other way is wrong and ends
6069 * in tears. Pre-reserving the amount we are going to add will always
6070 * be the right way, because otherwise if we have enough parallelism we
6071 * could end up with thousands of inodes all holding little bits of
6072 * reservations they were able to make previously and the only way to
6073 * reclaim that space is to ENOSPC out the operations and clear
6074 * everything out and try again, which is bad. This way we just
6075 * over-reserve slightly, and clean up the mess when we are done.
6077 calc_inode_reservations(fs_info, num_bytes, &meta_reserve,
6079 ret = btrfs_qgroup_reserve_meta_prealloc(root, qgroup_reserve, true);
6082 ret = reserve_metadata_bytes(root, block_rsv, meta_reserve, flush);
6087 * Now we need to update our outstanding extents and csum bytes _first_
6088 * and then add the reservation to the block_rsv. This keeps us from
6089 * racing with an ordered completion or some such that would think it
6090 * needs to free the reservation we just made.
6092 spin_lock(&inode->lock);
6093 nr_extents = count_max_extents(num_bytes);
6094 btrfs_mod_outstanding_extents(inode, nr_extents);
6095 inode->csum_bytes += num_bytes;
6096 btrfs_calculate_inode_block_rsv_size(fs_info, inode);
6097 spin_unlock(&inode->lock);
6099 /* Now we can safely add our space to our block rsv */
6100 block_rsv_add_bytes(block_rsv, meta_reserve, false);
6101 trace_btrfs_space_reservation(root->fs_info, "delalloc",
6102 btrfs_ino(inode), meta_reserve, 1);
6104 spin_lock(&block_rsv->lock);
6105 block_rsv->qgroup_rsv_reserved += qgroup_reserve;
6106 spin_unlock(&block_rsv->lock);
6109 mutex_unlock(&inode->delalloc_mutex);
6112 btrfs_qgroup_free_meta_prealloc(root, qgroup_reserve);
6114 btrfs_inode_rsv_release(inode, true);
6116 mutex_unlock(&inode->delalloc_mutex);
6121 * btrfs_delalloc_release_metadata - release a metadata reservation for an inode
6122 * @inode: the inode to release the reservation for.
6123 * @num_bytes: the number of bytes we are releasing.
6124 * @qgroup_free: free qgroup reservation or convert it to per-trans reservation
6126 * This will release the metadata reservation for an inode. This can be called
6127 * once we complete IO for a given set of bytes to release their metadata
6128 * reservations, or on error for the same reason.
6130 void btrfs_delalloc_release_metadata(struct btrfs_inode *inode, u64 num_bytes,
6133 struct btrfs_fs_info *fs_info = inode->root->fs_info;
6135 num_bytes = ALIGN(num_bytes, fs_info->sectorsize);
6136 spin_lock(&inode->lock);
6137 inode->csum_bytes -= num_bytes;
6138 btrfs_calculate_inode_block_rsv_size(fs_info, inode);
6139 spin_unlock(&inode->lock);
6141 if (btrfs_is_testing(fs_info))
6144 btrfs_inode_rsv_release(inode, qgroup_free);
6148 * btrfs_delalloc_release_extents - release our outstanding_extents
6149 * @inode: the inode to balance the reservation for.
6150 * @num_bytes: the number of bytes we originally reserved with
6151 * @qgroup_free: do we need to free qgroup meta reservation or convert them.
6153 * When we reserve space we increase outstanding_extents for the extents we may
6154 * add. Once we've set the range as delalloc or created our ordered extents we
6155 * have outstanding_extents to track the real usage, so we use this to free our
6156 * temporarily tracked outstanding_extents. This _must_ be used in conjunction
6157 * with btrfs_delalloc_reserve_metadata.
6159 void btrfs_delalloc_release_extents(struct btrfs_inode *inode, u64 num_bytes,
6162 struct btrfs_fs_info *fs_info = inode->root->fs_info;
6163 unsigned num_extents;
6165 spin_lock(&inode->lock);
6166 num_extents = count_max_extents(num_bytes);
6167 btrfs_mod_outstanding_extents(inode, -num_extents);
6168 btrfs_calculate_inode_block_rsv_size(fs_info, inode);
6169 spin_unlock(&inode->lock);
6171 if (btrfs_is_testing(fs_info))
6174 btrfs_inode_rsv_release(inode, qgroup_free);
6178 * btrfs_delalloc_reserve_space - reserve data and metadata space for
6180 * @inode: inode we're writing to
6181 * @start: start range we are writing to
6182 * @len: how long the range we are writing to
6183 * @reserved: mandatory parameter, record actually reserved qgroup ranges of
6184 * current reservation.
6186 * This will do the following things
6188 * o reserve space in data space info for num bytes
6189 * and reserve precious corresponding qgroup space
6190 * (Done in check_data_free_space)
6192 * o reserve space for metadata space, based on the number of outstanding
6193 * extents and how much csums will be needed
6194 * also reserve metadata space in a per root over-reserve method.
6195 * o add to the inodes->delalloc_bytes
6196 * o add it to the fs_info's delalloc inodes list.
6197 * (Above 3 all done in delalloc_reserve_metadata)
6199 * Return 0 for success
6200 * Return <0 for error(-ENOSPC or -EQUOT)
6202 int btrfs_delalloc_reserve_space(struct inode *inode,
6203 struct extent_changeset **reserved, u64 start, u64 len)
6207 ret = btrfs_check_data_free_space(inode, reserved, start, len);
6210 ret = btrfs_delalloc_reserve_metadata(BTRFS_I(inode), len);
6212 btrfs_free_reserved_data_space(inode, *reserved, start, len);
6217 * btrfs_delalloc_release_space - release data and metadata space for delalloc
6218 * @inode: inode we're releasing space for
6219 * @start: start position of the space already reserved
6220 * @len: the len of the space already reserved
6221 * @release_bytes: the len of the space we consumed or didn't use
6223 * This function will release the metadata space that was not used and will
6224 * decrement ->delalloc_bytes and remove it from the fs_info delalloc_inodes
6225 * list if there are no delalloc bytes left.
6226 * Also it will handle the qgroup reserved space.
6228 void btrfs_delalloc_release_space(struct inode *inode,
6229 struct extent_changeset *reserved,
6230 u64 start, u64 len, bool qgroup_free)
6232 btrfs_delalloc_release_metadata(BTRFS_I(inode), len, qgroup_free);
6233 btrfs_free_reserved_data_space(inode, reserved, start, len);
6236 static int update_block_group(struct btrfs_trans_handle *trans,
6237 u64 bytenr, u64 num_bytes, int alloc)
6239 struct btrfs_fs_info *info = trans->fs_info;
6240 struct btrfs_block_group_cache *cache = NULL;
6241 u64 total = num_bytes;
6247 /* block accounting for super block */
6248 spin_lock(&info->delalloc_root_lock);
6249 old_val = btrfs_super_bytes_used(info->super_copy);
6251 old_val += num_bytes;
6253 old_val -= num_bytes;
6254 btrfs_set_super_bytes_used(info->super_copy, old_val);
6255 spin_unlock(&info->delalloc_root_lock);
6258 cache = btrfs_lookup_block_group(info, bytenr);
6263 factor = btrfs_bg_type_to_factor(cache->flags);
6266 * If this block group has free space cache written out, we
6267 * need to make sure to load it if we are removing space. This
6268 * is because we need the unpinning stage to actually add the
6269 * space back to the block group, otherwise we will leak space.
6271 if (!alloc && cache->cached == BTRFS_CACHE_NO)
6272 cache_block_group(cache, 1);
6274 byte_in_group = bytenr - cache->key.objectid;
6275 WARN_ON(byte_in_group > cache->key.offset);
6277 spin_lock(&cache->space_info->lock);
6278 spin_lock(&cache->lock);
6280 if (btrfs_test_opt(info, SPACE_CACHE) &&
6281 cache->disk_cache_state < BTRFS_DC_CLEAR)
6282 cache->disk_cache_state = BTRFS_DC_CLEAR;
6284 old_val = btrfs_block_group_used(&cache->item);
6285 num_bytes = min(total, cache->key.offset - byte_in_group);
6287 old_val += num_bytes;
6288 btrfs_set_block_group_used(&cache->item, old_val);
6289 cache->reserved -= num_bytes;
6290 cache->space_info->bytes_reserved -= num_bytes;
6291 cache->space_info->bytes_used += num_bytes;
6292 cache->space_info->disk_used += num_bytes * factor;
6293 spin_unlock(&cache->lock);
6294 spin_unlock(&cache->space_info->lock);
6296 old_val -= num_bytes;
6297 btrfs_set_block_group_used(&cache->item, old_val);
6298 cache->pinned += num_bytes;
6299 update_bytes_pinned(cache->space_info, num_bytes);
6300 cache->space_info->bytes_used -= num_bytes;
6301 cache->space_info->disk_used -= num_bytes * factor;
6302 spin_unlock(&cache->lock);
6303 spin_unlock(&cache->space_info->lock);
6305 trace_btrfs_space_reservation(info, "pinned",
6306 cache->space_info->flags,
6308 percpu_counter_add_batch(&cache->space_info->total_bytes_pinned,
6310 BTRFS_TOTAL_BYTES_PINNED_BATCH);
6311 set_extent_dirty(info->pinned_extents,
6312 bytenr, bytenr + num_bytes - 1,
6313 GFP_NOFS | __GFP_NOFAIL);
6316 spin_lock(&trans->transaction->dirty_bgs_lock);
6317 if (list_empty(&cache->dirty_list)) {
6318 list_add_tail(&cache->dirty_list,
6319 &trans->transaction->dirty_bgs);
6320 trans->delayed_ref_updates++;
6321 btrfs_get_block_group(cache);
6323 spin_unlock(&trans->transaction->dirty_bgs_lock);
6326 * No longer have used bytes in this block group, queue it for
6327 * deletion. We do this after adding the block group to the
6328 * dirty list to avoid races between cleaner kthread and space
6331 if (!alloc && old_val == 0)
6332 btrfs_mark_bg_unused(cache);
6334 btrfs_put_block_group(cache);
6336 bytenr += num_bytes;
6339 /* Modified block groups are accounted for in the delayed_refs_rsv. */
6340 btrfs_update_delayed_refs_rsv(trans);
6344 static u64 first_logical_byte(struct btrfs_fs_info *fs_info, u64 search_start)
6346 struct btrfs_block_group_cache *cache;
6349 spin_lock(&fs_info->block_group_cache_lock);
6350 bytenr = fs_info->first_logical_byte;
6351 spin_unlock(&fs_info->block_group_cache_lock);
6353 if (bytenr < (u64)-1)
6356 cache = btrfs_lookup_first_block_group(fs_info, search_start);
6360 bytenr = cache->key.objectid;
6361 btrfs_put_block_group(cache);
6366 static int pin_down_extent(struct btrfs_block_group_cache *cache,
6367 u64 bytenr, u64 num_bytes, int reserved)
6369 struct btrfs_fs_info *fs_info = cache->fs_info;
6371 spin_lock(&cache->space_info->lock);
6372 spin_lock(&cache->lock);
6373 cache->pinned += num_bytes;
6374 update_bytes_pinned(cache->space_info, num_bytes);
6376 cache->reserved -= num_bytes;
6377 cache->space_info->bytes_reserved -= num_bytes;
6379 spin_unlock(&cache->lock);
6380 spin_unlock(&cache->space_info->lock);
6382 trace_btrfs_space_reservation(fs_info, "pinned",
6383 cache->space_info->flags, num_bytes, 1);
6384 percpu_counter_add_batch(&cache->space_info->total_bytes_pinned,
6385 num_bytes, BTRFS_TOTAL_BYTES_PINNED_BATCH);
6386 set_extent_dirty(fs_info->pinned_extents, bytenr,
6387 bytenr + num_bytes - 1, GFP_NOFS | __GFP_NOFAIL);
6392 * this function must be called within transaction
6394 int btrfs_pin_extent(struct btrfs_fs_info *fs_info,
6395 u64 bytenr, u64 num_bytes, int reserved)
6397 struct btrfs_block_group_cache *cache;
6399 cache = btrfs_lookup_block_group(fs_info, bytenr);
6400 BUG_ON(!cache); /* Logic error */
6402 pin_down_extent(cache, bytenr, num_bytes, reserved);
6404 btrfs_put_block_group(cache);
6409 * this function must be called within transaction
6411 int btrfs_pin_extent_for_log_replay(struct btrfs_fs_info *fs_info,
6412 u64 bytenr, u64 num_bytes)
6414 struct btrfs_block_group_cache *cache;
6417 cache = btrfs_lookup_block_group(fs_info, bytenr);
6422 * pull in the free space cache (if any) so that our pin
6423 * removes the free space from the cache. We have load_only set
6424 * to one because the slow code to read in the free extents does check
6425 * the pinned extents.
6427 cache_block_group(cache, 1);
6429 pin_down_extent(cache, bytenr, num_bytes, 0);
6431 /* remove us from the free space cache (if we're there at all) */
6432 ret = btrfs_remove_free_space(cache, bytenr, num_bytes);
6433 btrfs_put_block_group(cache);
6437 static int __exclude_logged_extent(struct btrfs_fs_info *fs_info,
6438 u64 start, u64 num_bytes)
6441 struct btrfs_block_group_cache *block_group;
6442 struct btrfs_caching_control *caching_ctl;
6444 block_group = btrfs_lookup_block_group(fs_info, start);
6448 cache_block_group(block_group, 0);
6449 caching_ctl = get_caching_control(block_group);
6453 BUG_ON(!block_group_cache_done(block_group));
6454 ret = btrfs_remove_free_space(block_group, start, num_bytes);
6456 mutex_lock(&caching_ctl->mutex);
6458 if (start >= caching_ctl->progress) {
6459 ret = add_excluded_extent(fs_info, start, num_bytes);
6460 } else if (start + num_bytes <= caching_ctl->progress) {
6461 ret = btrfs_remove_free_space(block_group,
6464 num_bytes = caching_ctl->progress - start;
6465 ret = btrfs_remove_free_space(block_group,
6470 num_bytes = (start + num_bytes) -
6471 caching_ctl->progress;
6472 start = caching_ctl->progress;
6473 ret = add_excluded_extent(fs_info, start, num_bytes);
6476 mutex_unlock(&caching_ctl->mutex);
6477 put_caching_control(caching_ctl);
6479 btrfs_put_block_group(block_group);
6483 int btrfs_exclude_logged_extents(struct extent_buffer *eb)
6485 struct btrfs_fs_info *fs_info = eb->fs_info;
6486 struct btrfs_file_extent_item *item;
6487 struct btrfs_key key;
6492 if (!btrfs_fs_incompat(fs_info, MIXED_GROUPS))
6495 for (i = 0; i < btrfs_header_nritems(eb); i++) {
6496 btrfs_item_key_to_cpu(eb, &key, i);
6497 if (key.type != BTRFS_EXTENT_DATA_KEY)
6499 item = btrfs_item_ptr(eb, i, struct btrfs_file_extent_item);
6500 found_type = btrfs_file_extent_type(eb, item);
6501 if (found_type == BTRFS_FILE_EXTENT_INLINE)
6503 if (btrfs_file_extent_disk_bytenr(eb, item) == 0)
6505 key.objectid = btrfs_file_extent_disk_bytenr(eb, item);
6506 key.offset = btrfs_file_extent_disk_num_bytes(eb, item);
6507 ret = __exclude_logged_extent(fs_info, key.objectid, key.offset);
6516 btrfs_inc_block_group_reservations(struct btrfs_block_group_cache *bg)
6518 atomic_inc(&bg->reservations);
6521 void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info,
6524 struct btrfs_block_group_cache *bg;
6526 bg = btrfs_lookup_block_group(fs_info, start);
6528 if (atomic_dec_and_test(&bg->reservations))
6529 wake_up_var(&bg->reservations);
6530 btrfs_put_block_group(bg);
6533 void btrfs_wait_block_group_reservations(struct btrfs_block_group_cache *bg)
6535 struct btrfs_space_info *space_info = bg->space_info;
6539 if (!(bg->flags & BTRFS_BLOCK_GROUP_DATA))
6543 * Our block group is read only but before we set it to read only,
6544 * some task might have had allocated an extent from it already, but it
6545 * has not yet created a respective ordered extent (and added it to a
6546 * root's list of ordered extents).
6547 * Therefore wait for any task currently allocating extents, since the
6548 * block group's reservations counter is incremented while a read lock
6549 * on the groups' semaphore is held and decremented after releasing
6550 * the read access on that semaphore and creating the ordered extent.
6552 down_write(&space_info->groups_sem);
6553 up_write(&space_info->groups_sem);
6555 wait_var_event(&bg->reservations, !atomic_read(&bg->reservations));
6559 * btrfs_add_reserved_bytes - update the block_group and space info counters
6560 * @cache: The cache we are manipulating
6561 * @ram_bytes: The number of bytes of file content, and will be same to
6562 * @num_bytes except for the compress path.
6563 * @num_bytes: The number of bytes in question
6564 * @delalloc: The blocks are allocated for the delalloc write
6566 * This is called by the allocator when it reserves space. If this is a
6567 * reservation and the block group has become read only we cannot make the
6568 * reservation and return -EAGAIN, otherwise this function always succeeds.
6570 static int btrfs_add_reserved_bytes(struct btrfs_block_group_cache *cache,
6571 u64 ram_bytes, u64 num_bytes, int delalloc)
6573 struct btrfs_space_info *space_info = cache->space_info;
6576 spin_lock(&space_info->lock);
6577 spin_lock(&cache->lock);
6581 cache->reserved += num_bytes;
6582 space_info->bytes_reserved += num_bytes;
6583 update_bytes_may_use(space_info, -ram_bytes);
6585 cache->delalloc_bytes += num_bytes;
6587 spin_unlock(&cache->lock);
6588 spin_unlock(&space_info->lock);
6593 * btrfs_free_reserved_bytes - update the block_group and space info counters
6594 * @cache: The cache we are manipulating
6595 * @num_bytes: The number of bytes in question
6596 * @delalloc: The blocks are allocated for the delalloc write
6598 * This is called by somebody who is freeing space that was never actually used
6599 * on disk. For example if you reserve some space for a new leaf in transaction
6600 * A and before transaction A commits you free that leaf, you call this with
6601 * reserve set to 0 in order to clear the reservation.
6604 static void btrfs_free_reserved_bytes(struct btrfs_block_group_cache *cache,
6605 u64 num_bytes, int delalloc)
6607 struct btrfs_space_info *space_info = cache->space_info;
6609 spin_lock(&space_info->lock);
6610 spin_lock(&cache->lock);
6612 space_info->bytes_readonly += num_bytes;
6613 cache->reserved -= num_bytes;
6614 space_info->bytes_reserved -= num_bytes;
6615 space_info->max_extent_size = 0;
6618 cache->delalloc_bytes -= num_bytes;
6619 spin_unlock(&cache->lock);
6620 spin_unlock(&space_info->lock);
6622 void btrfs_prepare_extent_commit(struct btrfs_fs_info *fs_info)
6624 struct btrfs_caching_control *next;
6625 struct btrfs_caching_control *caching_ctl;
6626 struct btrfs_block_group_cache *cache;
6628 down_write(&fs_info->commit_root_sem);
6630 list_for_each_entry_safe(caching_ctl, next,
6631 &fs_info->caching_block_groups, list) {
6632 cache = caching_ctl->block_group;
6633 if (block_group_cache_done(cache)) {
6634 cache->last_byte_to_unpin = (u64)-1;
6635 list_del_init(&caching_ctl->list);
6636 put_caching_control(caching_ctl);
6638 cache->last_byte_to_unpin = caching_ctl->progress;
6642 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
6643 fs_info->pinned_extents = &fs_info->freed_extents[1];
6645 fs_info->pinned_extents = &fs_info->freed_extents[0];
6647 up_write(&fs_info->commit_root_sem);
6649 update_global_block_rsv(fs_info);
6653 * Returns the free cluster for the given space info and sets empty_cluster to
6654 * what it should be based on the mount options.
6656 static struct btrfs_free_cluster *
6657 fetch_cluster_info(struct btrfs_fs_info *fs_info,
6658 struct btrfs_space_info *space_info, u64 *empty_cluster)
6660 struct btrfs_free_cluster *ret = NULL;
6663 if (btrfs_mixed_space_info(space_info))
6666 if (space_info->flags & BTRFS_BLOCK_GROUP_METADATA) {
6667 ret = &fs_info->meta_alloc_cluster;
6668 if (btrfs_test_opt(fs_info, SSD))
6669 *empty_cluster = SZ_2M;
6671 *empty_cluster = SZ_64K;
6672 } else if ((space_info->flags & BTRFS_BLOCK_GROUP_DATA) &&
6673 btrfs_test_opt(fs_info, SSD_SPREAD)) {
6674 *empty_cluster = SZ_2M;
6675 ret = &fs_info->data_alloc_cluster;
6681 static int unpin_extent_range(struct btrfs_fs_info *fs_info,
6683 const bool return_free_space)
6685 struct btrfs_block_group_cache *cache = NULL;
6686 struct btrfs_space_info *space_info;
6687 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
6688 struct btrfs_free_cluster *cluster = NULL;
6690 u64 total_unpinned = 0;
6691 u64 empty_cluster = 0;
6694 while (start <= end) {
6697 start >= cache->key.objectid + cache->key.offset) {
6699 btrfs_put_block_group(cache);
6701 cache = btrfs_lookup_block_group(fs_info, start);
6702 BUG_ON(!cache); /* Logic error */
6704 cluster = fetch_cluster_info(fs_info,
6707 empty_cluster <<= 1;
6710 len = cache->key.objectid + cache->key.offset - start;
6711 len = min(len, end + 1 - start);
6713 if (start < cache->last_byte_to_unpin) {
6714 len = min(len, cache->last_byte_to_unpin - start);
6715 if (return_free_space)
6716 btrfs_add_free_space(cache, start, len);
6720 total_unpinned += len;
6721 space_info = cache->space_info;
6724 * If this space cluster has been marked as fragmented and we've
6725 * unpinned enough in this block group to potentially allow a
6726 * cluster to be created inside of it go ahead and clear the
6729 if (cluster && cluster->fragmented &&
6730 total_unpinned > empty_cluster) {
6731 spin_lock(&cluster->lock);
6732 cluster->fragmented = 0;
6733 spin_unlock(&cluster->lock);
6736 spin_lock(&space_info->lock);
6737 spin_lock(&cache->lock);
6738 cache->pinned -= len;
6739 update_bytes_pinned(space_info, -len);
6741 trace_btrfs_space_reservation(fs_info, "pinned",
6742 space_info->flags, len, 0);
6743 space_info->max_extent_size = 0;
6744 percpu_counter_add_batch(&space_info->total_bytes_pinned,
6745 -len, BTRFS_TOTAL_BYTES_PINNED_BATCH);
6747 space_info->bytes_readonly += len;
6750 spin_unlock(&cache->lock);
6751 if (!readonly && return_free_space &&
6752 global_rsv->space_info == space_info) {
6755 spin_lock(&global_rsv->lock);
6756 if (!global_rsv->full) {
6757 to_add = min(len, global_rsv->size -
6758 global_rsv->reserved);
6759 global_rsv->reserved += to_add;
6760 update_bytes_may_use(space_info, to_add);
6761 if (global_rsv->reserved >= global_rsv->size)
6762 global_rsv->full = 1;
6763 trace_btrfs_space_reservation(fs_info,
6769 spin_unlock(&global_rsv->lock);
6770 /* Add to any tickets we may have */
6772 space_info_add_new_bytes(fs_info, space_info,
6775 spin_unlock(&space_info->lock);
6779 btrfs_put_block_group(cache);
6783 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans)
6785 struct btrfs_fs_info *fs_info = trans->fs_info;
6786 struct btrfs_block_group_cache *block_group, *tmp;
6787 struct list_head *deleted_bgs;
6788 struct extent_io_tree *unpin;
6793 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
6794 unpin = &fs_info->freed_extents[1];
6796 unpin = &fs_info->freed_extents[0];
6798 while (!trans->aborted) {
6799 struct extent_state *cached_state = NULL;
6801 mutex_lock(&fs_info->unused_bg_unpin_mutex);
6802 ret = find_first_extent_bit(unpin, 0, &start, &end,
6803 EXTENT_DIRTY, &cached_state);
6805 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
6809 if (btrfs_test_opt(fs_info, DISCARD))
6810 ret = btrfs_discard_extent(fs_info, start,
6811 end + 1 - start, NULL);
6813 clear_extent_dirty(unpin, start, end, &cached_state);
6814 unpin_extent_range(fs_info, start, end, true);
6815 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
6816 free_extent_state(cached_state);
6821 * Transaction is finished. We don't need the lock anymore. We
6822 * do need to clean up the block groups in case of a transaction
6825 deleted_bgs = &trans->transaction->deleted_bgs;
6826 list_for_each_entry_safe(block_group, tmp, deleted_bgs, bg_list) {
6830 if (!trans->aborted)
6831 ret = btrfs_discard_extent(fs_info,
6832 block_group->key.objectid,
6833 block_group->key.offset,
6836 list_del_init(&block_group->bg_list);
6837 btrfs_put_block_group_trimming(block_group);
6838 btrfs_put_block_group(block_group);
6841 const char *errstr = btrfs_decode_error(ret);
6843 "discard failed while removing blockgroup: errno=%d %s",
6851 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
6852 struct btrfs_delayed_ref_node *node, u64 parent,
6853 u64 root_objectid, u64 owner_objectid,
6854 u64 owner_offset, int refs_to_drop,
6855 struct btrfs_delayed_extent_op *extent_op)
6857 struct btrfs_fs_info *info = trans->fs_info;
6858 struct btrfs_key key;
6859 struct btrfs_path *path;
6860 struct btrfs_root *extent_root = info->extent_root;
6861 struct extent_buffer *leaf;
6862 struct btrfs_extent_item *ei;
6863 struct btrfs_extent_inline_ref *iref;
6866 int extent_slot = 0;
6867 int found_extent = 0;
6871 u64 bytenr = node->bytenr;
6872 u64 num_bytes = node->num_bytes;
6874 bool skinny_metadata = btrfs_fs_incompat(info, SKINNY_METADATA);
6876 path = btrfs_alloc_path();
6880 path->reada = READA_FORWARD;
6881 path->leave_spinning = 1;
6883 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
6884 BUG_ON(!is_data && refs_to_drop != 1);
6887 skinny_metadata = false;
6889 ret = lookup_extent_backref(trans, path, &iref, bytenr, num_bytes,
6890 parent, root_objectid, owner_objectid,
6893 extent_slot = path->slots[0];
6894 while (extent_slot >= 0) {
6895 btrfs_item_key_to_cpu(path->nodes[0], &key,
6897 if (key.objectid != bytenr)
6899 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
6900 key.offset == num_bytes) {
6904 if (key.type == BTRFS_METADATA_ITEM_KEY &&
6905 key.offset == owner_objectid) {
6909 if (path->slots[0] - extent_slot > 5)
6914 if (!found_extent) {
6916 ret = remove_extent_backref(trans, path, NULL,
6918 is_data, &last_ref);
6920 btrfs_abort_transaction(trans, ret);
6923 btrfs_release_path(path);
6924 path->leave_spinning = 1;
6926 key.objectid = bytenr;
6927 key.type = BTRFS_EXTENT_ITEM_KEY;
6928 key.offset = num_bytes;
6930 if (!is_data && skinny_metadata) {
6931 key.type = BTRFS_METADATA_ITEM_KEY;
6932 key.offset = owner_objectid;
6935 ret = btrfs_search_slot(trans, extent_root,
6937 if (ret > 0 && skinny_metadata && path->slots[0]) {
6939 * Couldn't find our skinny metadata item,
6940 * see if we have ye olde extent item.
6943 btrfs_item_key_to_cpu(path->nodes[0], &key,
6945 if (key.objectid == bytenr &&
6946 key.type == BTRFS_EXTENT_ITEM_KEY &&
6947 key.offset == num_bytes)
6951 if (ret > 0 && skinny_metadata) {
6952 skinny_metadata = false;
6953 key.objectid = bytenr;
6954 key.type = BTRFS_EXTENT_ITEM_KEY;
6955 key.offset = num_bytes;
6956 btrfs_release_path(path);
6957 ret = btrfs_search_slot(trans, extent_root,
6963 "umm, got %d back from search, was looking for %llu",
6966 btrfs_print_leaf(path->nodes[0]);
6969 btrfs_abort_transaction(trans, ret);
6972 extent_slot = path->slots[0];
6974 } else if (WARN_ON(ret == -ENOENT)) {
6975 btrfs_print_leaf(path->nodes[0]);
6977 "unable to find ref byte nr %llu parent %llu root %llu owner %llu offset %llu",
6978 bytenr, parent, root_objectid, owner_objectid,
6980 btrfs_abort_transaction(trans, ret);
6983 btrfs_abort_transaction(trans, ret);
6987 leaf = path->nodes[0];
6988 item_size = btrfs_item_size_nr(leaf, extent_slot);
6989 if (unlikely(item_size < sizeof(*ei))) {
6991 btrfs_print_v0_err(info);
6992 btrfs_abort_transaction(trans, ret);
6995 ei = btrfs_item_ptr(leaf, extent_slot,
6996 struct btrfs_extent_item);
6997 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID &&
6998 key.type == BTRFS_EXTENT_ITEM_KEY) {
6999 struct btrfs_tree_block_info *bi;
7000 BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
7001 bi = (struct btrfs_tree_block_info *)(ei + 1);
7002 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
7005 refs = btrfs_extent_refs(leaf, ei);
7006 if (refs < refs_to_drop) {
7008 "trying to drop %d refs but we only have %Lu for bytenr %Lu",
7009 refs_to_drop, refs, bytenr);
7011 btrfs_abort_transaction(trans, ret);
7014 refs -= refs_to_drop;
7018 __run_delayed_extent_op(extent_op, leaf, ei);
7020 * In the case of inline back ref, reference count will
7021 * be updated by remove_extent_backref
7024 BUG_ON(!found_extent);
7026 btrfs_set_extent_refs(leaf, ei, refs);
7027 btrfs_mark_buffer_dirty(leaf);
7030 ret = remove_extent_backref(trans, path, iref,
7031 refs_to_drop, is_data,
7034 btrfs_abort_transaction(trans, ret);
7040 BUG_ON(is_data && refs_to_drop !=
7041 extent_data_ref_count(path, iref));
7043 BUG_ON(path->slots[0] != extent_slot);
7045 BUG_ON(path->slots[0] != extent_slot + 1);
7046 path->slots[0] = extent_slot;
7052 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
7055 btrfs_abort_transaction(trans, ret);
7058 btrfs_release_path(path);
7061 ret = btrfs_del_csums(trans, info, bytenr, num_bytes);
7063 btrfs_abort_transaction(trans, ret);
7068 ret = add_to_free_space_tree(trans, bytenr, num_bytes);
7070 btrfs_abort_transaction(trans, ret);
7074 ret = update_block_group(trans, bytenr, num_bytes, 0);
7076 btrfs_abort_transaction(trans, ret);
7080 btrfs_release_path(path);
7083 btrfs_free_path(path);
7088 * when we free an block, it is possible (and likely) that we free the last
7089 * delayed ref for that extent as well. This searches the delayed ref tree for
7090 * a given extent, and if there are no other delayed refs to be processed, it
7091 * removes it from the tree.
7093 static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans,
7096 struct btrfs_delayed_ref_head *head;
7097 struct btrfs_delayed_ref_root *delayed_refs;
7100 delayed_refs = &trans->transaction->delayed_refs;
7101 spin_lock(&delayed_refs->lock);
7102 head = btrfs_find_delayed_ref_head(delayed_refs, bytenr);
7104 goto out_delayed_unlock;
7106 spin_lock(&head->lock);
7107 if (!RB_EMPTY_ROOT(&head->ref_tree.rb_root))
7110 if (cleanup_extent_op(head) != NULL)
7114 * waiting for the lock here would deadlock. If someone else has it
7115 * locked they are already in the process of dropping it anyway
7117 if (!mutex_trylock(&head->mutex))
7120 btrfs_delete_ref_head(delayed_refs, head);
7121 head->processing = 0;
7123 spin_unlock(&head->lock);
7124 spin_unlock(&delayed_refs->lock);
7126 BUG_ON(head->extent_op);
7127 if (head->must_insert_reserved)
7130 btrfs_cleanup_ref_head_accounting(trans->fs_info, delayed_refs, head);
7131 mutex_unlock(&head->mutex);
7132 btrfs_put_delayed_ref_head(head);
7135 spin_unlock(&head->lock);
7138 spin_unlock(&delayed_refs->lock);
7142 void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
7143 struct btrfs_root *root,
7144 struct extent_buffer *buf,
7145 u64 parent, int last_ref)
7147 struct btrfs_fs_info *fs_info = root->fs_info;
7148 struct btrfs_ref generic_ref = { 0 };
7152 btrfs_init_generic_ref(&generic_ref, BTRFS_DROP_DELAYED_REF,
7153 buf->start, buf->len, parent);
7154 btrfs_init_tree_ref(&generic_ref, btrfs_header_level(buf),
7155 root->root_key.objectid);
7157 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
7158 int old_ref_mod, new_ref_mod;
7160 btrfs_ref_tree_mod(fs_info, &generic_ref);
7161 ret = btrfs_add_delayed_tree_ref(trans, &generic_ref, NULL,
7162 &old_ref_mod, &new_ref_mod);
7163 BUG_ON(ret); /* -ENOMEM */
7164 pin = old_ref_mod >= 0 && new_ref_mod < 0;
7167 if (last_ref && btrfs_header_generation(buf) == trans->transid) {
7168 struct btrfs_block_group_cache *cache;
7170 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
7171 ret = check_ref_cleanup(trans, buf->start);
7177 cache = btrfs_lookup_block_group(fs_info, buf->start);
7179 if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
7180 pin_down_extent(cache, buf->start, buf->len, 1);
7181 btrfs_put_block_group(cache);
7185 WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags));
7187 btrfs_add_free_space(cache, buf->start, buf->len);
7188 btrfs_free_reserved_bytes(cache, buf->len, 0);
7189 btrfs_put_block_group(cache);
7190 trace_btrfs_reserved_extent_free(fs_info, buf->start, buf->len);
7194 add_pinned_bytes(fs_info, &generic_ref, 1);
7198 * Deleting the buffer, clear the corrupt flag since it doesn't
7201 clear_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags);
7205 /* Can return -ENOMEM */
7206 int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_ref *ref)
7208 struct btrfs_fs_info *fs_info = trans->fs_info;
7209 int old_ref_mod, new_ref_mod;
7212 if (btrfs_is_testing(fs_info))
7216 * tree log blocks never actually go into the extent allocation
7217 * tree, just update pinning info and exit early.
7219 if ((ref->type == BTRFS_REF_METADATA &&
7220 ref->tree_ref.root == BTRFS_TREE_LOG_OBJECTID) ||
7221 (ref->type == BTRFS_REF_DATA &&
7222 ref->data_ref.ref_root == BTRFS_TREE_LOG_OBJECTID)) {
7223 /* unlocks the pinned mutex */
7224 btrfs_pin_extent(fs_info, ref->bytenr, ref->len, 1);
7225 old_ref_mod = new_ref_mod = 0;
7227 } else if (ref->type == BTRFS_REF_METADATA) {
7228 ret = btrfs_add_delayed_tree_ref(trans, ref, NULL,
7229 &old_ref_mod, &new_ref_mod);
7231 ret = btrfs_add_delayed_data_ref(trans, ref, 0,
7232 &old_ref_mod, &new_ref_mod);
7235 if (!((ref->type == BTRFS_REF_METADATA &&
7236 ref->tree_ref.root == BTRFS_TREE_LOG_OBJECTID) ||
7237 (ref->type == BTRFS_REF_DATA &&
7238 ref->data_ref.ref_root == BTRFS_TREE_LOG_OBJECTID)))
7239 btrfs_ref_tree_mod(fs_info, ref);
7241 if (ret == 0 && old_ref_mod >= 0 && new_ref_mod < 0)
7242 add_pinned_bytes(fs_info, ref, 1);
7248 * when we wait for progress in the block group caching, its because
7249 * our allocation attempt failed at least once. So, we must sleep
7250 * and let some progress happen before we try again.
7252 * This function will sleep at least once waiting for new free space to
7253 * show up, and then it will check the block group free space numbers
7254 * for our min num_bytes. Another option is to have it go ahead
7255 * and look in the rbtree for a free extent of a given size, but this
7258 * Callers of this must check if cache->cached == BTRFS_CACHE_ERROR before using
7259 * any of the information in this block group.
7261 static noinline void
7262 wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
7265 struct btrfs_caching_control *caching_ctl;
7267 caching_ctl = get_caching_control(cache);
7271 wait_event(caching_ctl->wait, block_group_cache_done(cache) ||
7272 (cache->free_space_ctl->free_space >= num_bytes));
7274 put_caching_control(caching_ctl);
7278 wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
7280 struct btrfs_caching_control *caching_ctl;
7283 caching_ctl = get_caching_control(cache);
7285 return (cache->cached == BTRFS_CACHE_ERROR) ? -EIO : 0;
7287 wait_event(caching_ctl->wait, block_group_cache_done(cache));
7288 if (cache->cached == BTRFS_CACHE_ERROR)
7290 put_caching_control(caching_ctl);
7294 enum btrfs_loop_type {
7295 LOOP_CACHING_NOWAIT = 0,
7296 LOOP_CACHING_WAIT = 1,
7297 LOOP_ALLOC_CHUNK = 2,
7298 LOOP_NO_EMPTY_SIZE = 3,
7302 btrfs_lock_block_group(struct btrfs_block_group_cache *cache,
7306 down_read(&cache->data_rwsem);
7310 btrfs_grab_block_group(struct btrfs_block_group_cache *cache,
7313 btrfs_get_block_group(cache);
7315 down_read(&cache->data_rwsem);
7318 static struct btrfs_block_group_cache *
7319 btrfs_lock_cluster(struct btrfs_block_group_cache *block_group,
7320 struct btrfs_free_cluster *cluster,
7323 struct btrfs_block_group_cache *used_bg = NULL;
7325 spin_lock(&cluster->refill_lock);
7327 used_bg = cluster->block_group;
7331 if (used_bg == block_group)
7334 btrfs_get_block_group(used_bg);
7339 if (down_read_trylock(&used_bg->data_rwsem))
7342 spin_unlock(&cluster->refill_lock);
7344 /* We should only have one-level nested. */
7345 down_read_nested(&used_bg->data_rwsem, SINGLE_DEPTH_NESTING);
7347 spin_lock(&cluster->refill_lock);
7348 if (used_bg == cluster->block_group)
7351 up_read(&used_bg->data_rwsem);
7352 btrfs_put_block_group(used_bg);
7357 btrfs_release_block_group(struct btrfs_block_group_cache *cache,
7361 up_read(&cache->data_rwsem);
7362 btrfs_put_block_group(cache);
7366 * Structure used internally for find_free_extent() function. Wraps needed
7369 struct find_free_extent_ctl {
7370 /* Basic allocation info */
7377 /* Where to start the search inside the bg */
7380 /* For clustered allocation */
7383 bool have_caching_bg;
7384 bool orig_have_caching_bg;
7386 /* RAID index, converted from flags */
7390 * Current loop number, check find_free_extent_update_loop() for details
7395 * Whether we're refilling a cluster, if true we need to re-search
7396 * current block group but don't try to refill the cluster again.
7398 bool retry_clustered;
7401 * Whether we're updating free space cache, if true we need to re-search
7402 * current block group but don't try updating free space cache again.
7404 bool retry_unclustered;
7406 /* If current block group is cached */
7409 /* Max contiguous hole found */
7410 u64 max_extent_size;
7412 /* Total free space from free space cache, not always contiguous */
7413 u64 total_free_space;
7421 * Helper function for find_free_extent().
7423 * Return -ENOENT to inform caller that we need fallback to unclustered mode.
7424 * Return -EAGAIN to inform caller that we need to re-search this block group
7425 * Return >0 to inform caller that we find nothing
7426 * Return 0 means we have found a location and set ffe_ctl->found_offset.
7428 static int find_free_extent_clustered(struct btrfs_block_group_cache *bg,
7429 struct btrfs_free_cluster *last_ptr,
7430 struct find_free_extent_ctl *ffe_ctl,
7431 struct btrfs_block_group_cache **cluster_bg_ret)
7433 struct btrfs_block_group_cache *cluster_bg;
7434 u64 aligned_cluster;
7438 cluster_bg = btrfs_lock_cluster(bg, last_ptr, ffe_ctl->delalloc);
7440 goto refill_cluster;
7441 if (cluster_bg != bg && (cluster_bg->ro ||
7442 !block_group_bits(cluster_bg, ffe_ctl->flags)))
7443 goto release_cluster;
7445 offset = btrfs_alloc_from_cluster(cluster_bg, last_ptr,
7446 ffe_ctl->num_bytes, cluster_bg->key.objectid,
7447 &ffe_ctl->max_extent_size);
7449 /* We have a block, we're done */
7450 spin_unlock(&last_ptr->refill_lock);
7451 trace_btrfs_reserve_extent_cluster(cluster_bg,
7452 ffe_ctl->search_start, ffe_ctl->num_bytes);
7453 *cluster_bg_ret = cluster_bg;
7454 ffe_ctl->found_offset = offset;
7457 WARN_ON(last_ptr->block_group != cluster_bg);
7461 * If we are on LOOP_NO_EMPTY_SIZE, we can't set up a new clusters, so
7462 * lets just skip it and let the allocator find whatever block it can
7463 * find. If we reach this point, we will have tried the cluster
7464 * allocator plenty of times and not have found anything, so we are
7465 * likely way too fragmented for the clustering stuff to find anything.
7467 * However, if the cluster is taken from the current block group,
7468 * release the cluster first, so that we stand a better chance of
7469 * succeeding in the unclustered allocation.
7471 if (ffe_ctl->loop >= LOOP_NO_EMPTY_SIZE && cluster_bg != bg) {
7472 spin_unlock(&last_ptr->refill_lock);
7473 btrfs_release_block_group(cluster_bg, ffe_ctl->delalloc);
7477 /* This cluster didn't work out, free it and start over */
7478 btrfs_return_cluster_to_free_space(NULL, last_ptr);
7480 if (cluster_bg != bg)
7481 btrfs_release_block_group(cluster_bg, ffe_ctl->delalloc);
7484 if (ffe_ctl->loop >= LOOP_NO_EMPTY_SIZE) {
7485 spin_unlock(&last_ptr->refill_lock);
7489 aligned_cluster = max_t(u64,
7490 ffe_ctl->empty_cluster + ffe_ctl->empty_size,
7491 bg->full_stripe_len);
7492 ret = btrfs_find_space_cluster(bg, last_ptr, ffe_ctl->search_start,
7493 ffe_ctl->num_bytes, aligned_cluster);
7495 /* Now pull our allocation out of this cluster */
7496 offset = btrfs_alloc_from_cluster(bg, last_ptr,
7497 ffe_ctl->num_bytes, ffe_ctl->search_start,
7498 &ffe_ctl->max_extent_size);
7500 /* We found one, proceed */
7501 spin_unlock(&last_ptr->refill_lock);
7502 trace_btrfs_reserve_extent_cluster(bg,
7503 ffe_ctl->search_start,
7504 ffe_ctl->num_bytes);
7505 ffe_ctl->found_offset = offset;
7508 } else if (!ffe_ctl->cached && ffe_ctl->loop > LOOP_CACHING_NOWAIT &&
7509 !ffe_ctl->retry_clustered) {
7510 spin_unlock(&last_ptr->refill_lock);
7512 ffe_ctl->retry_clustered = true;
7513 wait_block_group_cache_progress(bg, ffe_ctl->num_bytes +
7514 ffe_ctl->empty_cluster + ffe_ctl->empty_size);
7518 * At this point we either didn't find a cluster or we weren't able to
7519 * allocate a block from our cluster. Free the cluster we've been
7520 * trying to use, and go to the next block group.
7522 btrfs_return_cluster_to_free_space(NULL, last_ptr);
7523 spin_unlock(&last_ptr->refill_lock);
7528 * Return >0 to inform caller that we find nothing
7529 * Return 0 when we found an free extent and set ffe_ctrl->found_offset
7530 * Return -EAGAIN to inform caller that we need to re-search this block group
7532 static int find_free_extent_unclustered(struct btrfs_block_group_cache *bg,
7533 struct btrfs_free_cluster *last_ptr,
7534 struct find_free_extent_ctl *ffe_ctl)
7539 * We are doing an unclustered allocation, set the fragmented flag so
7540 * we don't bother trying to setup a cluster again until we get more
7543 if (unlikely(last_ptr)) {
7544 spin_lock(&last_ptr->lock);
7545 last_ptr->fragmented = 1;
7546 spin_unlock(&last_ptr->lock);
7548 if (ffe_ctl->cached) {
7549 struct btrfs_free_space_ctl *free_space_ctl;
7551 free_space_ctl = bg->free_space_ctl;
7552 spin_lock(&free_space_ctl->tree_lock);
7553 if (free_space_ctl->free_space <
7554 ffe_ctl->num_bytes + ffe_ctl->empty_cluster +
7555 ffe_ctl->empty_size) {
7556 ffe_ctl->total_free_space = max_t(u64,
7557 ffe_ctl->total_free_space,
7558 free_space_ctl->free_space);
7559 spin_unlock(&free_space_ctl->tree_lock);
7562 spin_unlock(&free_space_ctl->tree_lock);
7565 offset = btrfs_find_space_for_alloc(bg, ffe_ctl->search_start,
7566 ffe_ctl->num_bytes, ffe_ctl->empty_size,
7567 &ffe_ctl->max_extent_size);
7570 * If we didn't find a chunk, and we haven't failed on this block group
7571 * before, and this block group is in the middle of caching and we are
7572 * ok with waiting, then go ahead and wait for progress to be made, and
7573 * set @retry_unclustered to true.
7575 * If @retry_unclustered is true then we've already waited on this
7576 * block group once and should move on to the next block group.
7578 if (!offset && !ffe_ctl->retry_unclustered && !ffe_ctl->cached &&
7579 ffe_ctl->loop > LOOP_CACHING_NOWAIT) {
7580 wait_block_group_cache_progress(bg, ffe_ctl->num_bytes +
7581 ffe_ctl->empty_size);
7582 ffe_ctl->retry_unclustered = true;
7584 } else if (!offset) {
7587 ffe_ctl->found_offset = offset;
7592 * Return >0 means caller needs to re-search for free extent
7593 * Return 0 means we have the needed free extent.
7594 * Return <0 means we failed to locate any free extent.
7596 static int find_free_extent_update_loop(struct btrfs_fs_info *fs_info,
7597 struct btrfs_free_cluster *last_ptr,
7598 struct btrfs_key *ins,
7599 struct find_free_extent_ctl *ffe_ctl,
7600 int full_search, bool use_cluster)
7602 struct btrfs_root *root = fs_info->extent_root;
7605 if ((ffe_ctl->loop == LOOP_CACHING_NOWAIT) &&
7606 ffe_ctl->have_caching_bg && !ffe_ctl->orig_have_caching_bg)
7607 ffe_ctl->orig_have_caching_bg = true;
7609 if (!ins->objectid && ffe_ctl->loop >= LOOP_CACHING_WAIT &&
7610 ffe_ctl->have_caching_bg)
7613 if (!ins->objectid && ++(ffe_ctl->index) < BTRFS_NR_RAID_TYPES)
7616 if (ins->objectid) {
7617 if (!use_cluster && last_ptr) {
7618 spin_lock(&last_ptr->lock);
7619 last_ptr->window_start = ins->objectid;
7620 spin_unlock(&last_ptr->lock);
7626 * LOOP_CACHING_NOWAIT, search partially cached block groups, kicking
7627 * caching kthreads as we move along
7628 * LOOP_CACHING_WAIT, search everything, and wait if our bg is caching
7629 * LOOP_ALLOC_CHUNK, force a chunk allocation and try again
7630 * LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try
7633 if (ffe_ctl->loop < LOOP_NO_EMPTY_SIZE) {
7635 if (ffe_ctl->loop == LOOP_CACHING_NOWAIT) {
7637 * We want to skip the LOOP_CACHING_WAIT step if we
7638 * don't have any uncached bgs and we've already done a
7639 * full search through.
7641 if (ffe_ctl->orig_have_caching_bg || !full_search)
7642 ffe_ctl->loop = LOOP_CACHING_WAIT;
7644 ffe_ctl->loop = LOOP_ALLOC_CHUNK;
7649 if (ffe_ctl->loop == LOOP_ALLOC_CHUNK) {
7650 struct btrfs_trans_handle *trans;
7653 trans = current->journal_info;
7657 trans = btrfs_join_transaction(root);
7659 if (IS_ERR(trans)) {
7660 ret = PTR_ERR(trans);
7664 ret = do_chunk_alloc(trans, ffe_ctl->flags,
7668 * If we can't allocate a new chunk we've already looped
7669 * through at least once, move on to the NO_EMPTY_SIZE
7673 ffe_ctl->loop = LOOP_NO_EMPTY_SIZE;
7675 /* Do not bail out on ENOSPC since we can do more. */
7676 if (ret < 0 && ret != -ENOSPC)
7677 btrfs_abort_transaction(trans, ret);
7681 btrfs_end_transaction(trans);
7686 if (ffe_ctl->loop == LOOP_NO_EMPTY_SIZE) {
7688 * Don't loop again if we already have no empty_size and
7691 if (ffe_ctl->empty_size == 0 &&
7692 ffe_ctl->empty_cluster == 0)
7694 ffe_ctl->empty_size = 0;
7695 ffe_ctl->empty_cluster = 0;
7703 * walks the btree of allocated extents and find a hole of a given size.
7704 * The key ins is changed to record the hole:
7705 * ins->objectid == start position
7706 * ins->flags = BTRFS_EXTENT_ITEM_KEY
7707 * ins->offset == the size of the hole.
7708 * Any available blocks before search_start are skipped.
7710 * If there is no suitable free space, we will record the max size of
7711 * the free space extent currently.
7713 * The overall logic and call chain:
7715 * find_free_extent()
7716 * |- Iterate through all block groups
7717 * | |- Get a valid block group
7718 * | |- Try to do clustered allocation in that block group
7719 * | |- Try to do unclustered allocation in that block group
7720 * | |- Check if the result is valid
7721 * | | |- If valid, then exit
7722 * | |- Jump to next block group
7724 * |- Push harder to find free extents
7725 * |- If not found, re-iterate all block groups
7727 static noinline int find_free_extent(struct btrfs_fs_info *fs_info,
7728 u64 ram_bytes, u64 num_bytes, u64 empty_size,
7729 u64 hint_byte, struct btrfs_key *ins,
7730 u64 flags, int delalloc)
7733 struct btrfs_free_cluster *last_ptr = NULL;
7734 struct btrfs_block_group_cache *block_group = NULL;
7735 struct find_free_extent_ctl ffe_ctl = {0};
7736 struct btrfs_space_info *space_info;
7737 bool use_cluster = true;
7738 bool full_search = false;
7740 WARN_ON(num_bytes < fs_info->sectorsize);
7742 ffe_ctl.ram_bytes = ram_bytes;
7743 ffe_ctl.num_bytes = num_bytes;
7744 ffe_ctl.empty_size = empty_size;
7745 ffe_ctl.flags = flags;
7746 ffe_ctl.search_start = 0;
7747 ffe_ctl.retry_clustered = false;
7748 ffe_ctl.retry_unclustered = false;
7749 ffe_ctl.delalloc = delalloc;
7750 ffe_ctl.index = btrfs_bg_flags_to_raid_index(flags);
7751 ffe_ctl.have_caching_bg = false;
7752 ffe_ctl.orig_have_caching_bg = false;
7753 ffe_ctl.found_offset = 0;
7755 ins->type = BTRFS_EXTENT_ITEM_KEY;
7759 trace_find_free_extent(fs_info, num_bytes, empty_size, flags);
7761 space_info = __find_space_info(fs_info, flags);
7763 btrfs_err(fs_info, "No space info for %llu", flags);
7768 * If our free space is heavily fragmented we may not be able to make
7769 * big contiguous allocations, so instead of doing the expensive search
7770 * for free space, simply return ENOSPC with our max_extent_size so we
7771 * can go ahead and search for a more manageable chunk.
7773 * If our max_extent_size is large enough for our allocation simply
7774 * disable clustering since we will likely not be able to find enough
7775 * space to create a cluster and induce latency trying.
7777 if (unlikely(space_info->max_extent_size)) {
7778 spin_lock(&space_info->lock);
7779 if (space_info->max_extent_size &&
7780 num_bytes > space_info->max_extent_size) {
7781 ins->offset = space_info->max_extent_size;
7782 spin_unlock(&space_info->lock);
7784 } else if (space_info->max_extent_size) {
7785 use_cluster = false;
7787 spin_unlock(&space_info->lock);
7790 last_ptr = fetch_cluster_info(fs_info, space_info,
7791 &ffe_ctl.empty_cluster);
7793 spin_lock(&last_ptr->lock);
7794 if (last_ptr->block_group)
7795 hint_byte = last_ptr->window_start;
7796 if (last_ptr->fragmented) {
7798 * We still set window_start so we can keep track of the
7799 * last place we found an allocation to try and save
7802 hint_byte = last_ptr->window_start;
7803 use_cluster = false;
7805 spin_unlock(&last_ptr->lock);
7808 ffe_ctl.search_start = max(ffe_ctl.search_start,
7809 first_logical_byte(fs_info, 0));
7810 ffe_ctl.search_start = max(ffe_ctl.search_start, hint_byte);
7811 if (ffe_ctl.search_start == hint_byte) {
7812 block_group = btrfs_lookup_block_group(fs_info,
7813 ffe_ctl.search_start);
7815 * we don't want to use the block group if it doesn't match our
7816 * allocation bits, or if its not cached.
7818 * However if we are re-searching with an ideal block group
7819 * picked out then we don't care that the block group is cached.
7821 if (block_group && block_group_bits(block_group, flags) &&
7822 block_group->cached != BTRFS_CACHE_NO) {
7823 down_read(&space_info->groups_sem);
7824 if (list_empty(&block_group->list) ||
7827 * someone is removing this block group,
7828 * we can't jump into the have_block_group
7829 * target because our list pointers are not
7832 btrfs_put_block_group(block_group);
7833 up_read(&space_info->groups_sem);
7835 ffe_ctl.index = btrfs_bg_flags_to_raid_index(
7836 block_group->flags);
7837 btrfs_lock_block_group(block_group, delalloc);
7838 goto have_block_group;
7840 } else if (block_group) {
7841 btrfs_put_block_group(block_group);
7845 ffe_ctl.have_caching_bg = false;
7846 if (ffe_ctl.index == btrfs_bg_flags_to_raid_index(flags) ||
7849 down_read(&space_info->groups_sem);
7850 list_for_each_entry(block_group,
7851 &space_info->block_groups[ffe_ctl.index], list) {
7852 /* If the block group is read-only, we can skip it entirely. */
7853 if (unlikely(block_group->ro))
7856 btrfs_grab_block_group(block_group, delalloc);
7857 ffe_ctl.search_start = block_group->key.objectid;
7860 * this can happen if we end up cycling through all the
7861 * raid types, but we want to make sure we only allocate
7862 * for the proper type.
7864 if (!block_group_bits(block_group, flags)) {
7865 u64 extra = BTRFS_BLOCK_GROUP_DUP |
7866 BTRFS_BLOCK_GROUP_RAID1 |
7867 BTRFS_BLOCK_GROUP_RAID5 |
7868 BTRFS_BLOCK_GROUP_RAID6 |
7869 BTRFS_BLOCK_GROUP_RAID10;
7872 * if they asked for extra copies and this block group
7873 * doesn't provide them, bail. This does allow us to
7874 * fill raid0 from raid1.
7876 if ((flags & extra) && !(block_group->flags & extra))
7881 ffe_ctl.cached = block_group_cache_done(block_group);
7882 if (unlikely(!ffe_ctl.cached)) {
7883 ffe_ctl.have_caching_bg = true;
7884 ret = cache_block_group(block_group, 0);
7889 if (unlikely(block_group->cached == BTRFS_CACHE_ERROR))
7893 * Ok we want to try and use the cluster allocator, so
7896 if (last_ptr && use_cluster) {
7897 struct btrfs_block_group_cache *cluster_bg = NULL;
7899 ret = find_free_extent_clustered(block_group, last_ptr,
7900 &ffe_ctl, &cluster_bg);
7903 if (cluster_bg && cluster_bg != block_group) {
7904 btrfs_release_block_group(block_group,
7906 block_group = cluster_bg;
7909 } else if (ret == -EAGAIN) {
7910 goto have_block_group;
7911 } else if (ret > 0) {
7914 /* ret == -ENOENT case falls through */
7917 ret = find_free_extent_unclustered(block_group, last_ptr,
7920 goto have_block_group;
7923 /* ret == 0 case falls through */
7925 ffe_ctl.search_start = round_up(ffe_ctl.found_offset,
7926 fs_info->stripesize);
7928 /* move on to the next group */
7929 if (ffe_ctl.search_start + num_bytes >
7930 block_group->key.objectid + block_group->key.offset) {
7931 btrfs_add_free_space(block_group, ffe_ctl.found_offset,
7936 if (ffe_ctl.found_offset < ffe_ctl.search_start)
7937 btrfs_add_free_space(block_group, ffe_ctl.found_offset,
7938 ffe_ctl.search_start - ffe_ctl.found_offset);
7940 ret = btrfs_add_reserved_bytes(block_group, ram_bytes,
7941 num_bytes, delalloc);
7942 if (ret == -EAGAIN) {
7943 btrfs_add_free_space(block_group, ffe_ctl.found_offset,
7947 btrfs_inc_block_group_reservations(block_group);
7949 /* we are all good, lets return */
7950 ins->objectid = ffe_ctl.search_start;
7951 ins->offset = num_bytes;
7953 trace_btrfs_reserve_extent(block_group, ffe_ctl.search_start,
7955 btrfs_release_block_group(block_group, delalloc);
7958 ffe_ctl.retry_clustered = false;
7959 ffe_ctl.retry_unclustered = false;
7960 BUG_ON(btrfs_bg_flags_to_raid_index(block_group->flags) !=
7962 btrfs_release_block_group(block_group, delalloc);
7965 up_read(&space_info->groups_sem);
7967 ret = find_free_extent_update_loop(fs_info, last_ptr, ins, &ffe_ctl,
7968 full_search, use_cluster);
7972 if (ret == -ENOSPC) {
7974 * Use ffe_ctl->total_free_space as fallback if we can't find
7975 * any contiguous hole.
7977 if (!ffe_ctl.max_extent_size)
7978 ffe_ctl.max_extent_size = ffe_ctl.total_free_space;
7979 spin_lock(&space_info->lock);
7980 space_info->max_extent_size = ffe_ctl.max_extent_size;
7981 spin_unlock(&space_info->lock);
7982 ins->offset = ffe_ctl.max_extent_size;
7987 #define DUMP_BLOCK_RSV(fs_info, rsv_name) \
7989 struct btrfs_block_rsv *__rsv = &(fs_info)->rsv_name; \
7990 spin_lock(&__rsv->lock); \
7991 btrfs_info(fs_info, #rsv_name ": size %llu reserved %llu", \
7992 __rsv->size, __rsv->reserved); \
7993 spin_unlock(&__rsv->lock); \
7996 static void dump_space_info(struct btrfs_fs_info *fs_info,
7997 struct btrfs_space_info *info, u64 bytes,
7998 int dump_block_groups)
8000 struct btrfs_block_group_cache *cache;
8003 spin_lock(&info->lock);
8004 btrfs_info(fs_info, "space_info %llu has %llu free, is %sfull",
8006 info->total_bytes - btrfs_space_info_used(info, true),
8007 info->full ? "" : "not ");
8009 "space_info total=%llu, used=%llu, pinned=%llu, reserved=%llu, may_use=%llu, readonly=%llu",
8010 info->total_bytes, info->bytes_used, info->bytes_pinned,
8011 info->bytes_reserved, info->bytes_may_use,
8012 info->bytes_readonly);
8013 spin_unlock(&info->lock);
8015 DUMP_BLOCK_RSV(fs_info, global_block_rsv);
8016 DUMP_BLOCK_RSV(fs_info, trans_block_rsv);
8017 DUMP_BLOCK_RSV(fs_info, chunk_block_rsv);
8018 DUMP_BLOCK_RSV(fs_info, delayed_block_rsv);
8019 DUMP_BLOCK_RSV(fs_info, delayed_refs_rsv);
8021 if (!dump_block_groups)
8024 down_read(&info->groups_sem);
8026 list_for_each_entry(cache, &info->block_groups[index], list) {
8027 spin_lock(&cache->lock);
8029 "block group %llu has %llu bytes, %llu used %llu pinned %llu reserved %s",
8030 cache->key.objectid, cache->key.offset,
8031 btrfs_block_group_used(&cache->item), cache->pinned,
8032 cache->reserved, cache->ro ? "[readonly]" : "");
8033 btrfs_dump_free_space(cache, bytes);
8034 spin_unlock(&cache->lock);
8036 if (++index < BTRFS_NR_RAID_TYPES)
8038 up_read(&info->groups_sem);
8042 * btrfs_reserve_extent - entry point to the extent allocator. Tries to find a
8043 * hole that is at least as big as @num_bytes.
8045 * @root - The root that will contain this extent
8047 * @ram_bytes - The amount of space in ram that @num_bytes take. This
8048 * is used for accounting purposes. This value differs
8049 * from @num_bytes only in the case of compressed extents.
8051 * @num_bytes - Number of bytes to allocate on-disk.
8053 * @min_alloc_size - Indicates the minimum amount of space that the
8054 * allocator should try to satisfy. In some cases
8055 * @num_bytes may be larger than what is required and if
8056 * the filesystem is fragmented then allocation fails.
8057 * However, the presence of @min_alloc_size gives a
8058 * chance to try and satisfy the smaller allocation.
8060 * @empty_size - A hint that you plan on doing more COW. This is the
8061 * size in bytes the allocator should try to find free
8062 * next to the block it returns. This is just a hint and
8063 * may be ignored by the allocator.
8065 * @hint_byte - Hint to the allocator to start searching above the byte
8066 * address passed. It might be ignored.
8068 * @ins - This key is modified to record the found hole. It will
8069 * have the following values:
8070 * ins->objectid == start position
8071 * ins->flags = BTRFS_EXTENT_ITEM_KEY
8072 * ins->offset == the size of the hole.
8074 * @is_data - Boolean flag indicating whether an extent is
8075 * allocated for data (true) or metadata (false)
8077 * @delalloc - Boolean flag indicating whether this allocation is for
8078 * delalloc or not. If 'true' data_rwsem of block groups
8079 * is going to be acquired.
8082 * Returns 0 when an allocation succeeded or < 0 when an error occurred. In
8083 * case -ENOSPC is returned then @ins->offset will contain the size of the
8084 * largest available hole the allocator managed to find.
8086 int btrfs_reserve_extent(struct btrfs_root *root, u64 ram_bytes,
8087 u64 num_bytes, u64 min_alloc_size,
8088 u64 empty_size, u64 hint_byte,
8089 struct btrfs_key *ins, int is_data, int delalloc)
8091 struct btrfs_fs_info *fs_info = root->fs_info;
8092 bool final_tried = num_bytes == min_alloc_size;
8096 flags = get_alloc_profile_by_root(root, is_data);
8098 WARN_ON(num_bytes < fs_info->sectorsize);
8099 ret = find_free_extent(fs_info, ram_bytes, num_bytes, empty_size,
8100 hint_byte, ins, flags, delalloc);
8101 if (!ret && !is_data) {
8102 btrfs_dec_block_group_reservations(fs_info, ins->objectid);
8103 } else if (ret == -ENOSPC) {
8104 if (!final_tried && ins->offset) {
8105 num_bytes = min(num_bytes >> 1, ins->offset);
8106 num_bytes = round_down(num_bytes,
8107 fs_info->sectorsize);
8108 num_bytes = max(num_bytes, min_alloc_size);
8109 ram_bytes = num_bytes;
8110 if (num_bytes == min_alloc_size)
8113 } else if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
8114 struct btrfs_space_info *sinfo;
8116 sinfo = __find_space_info(fs_info, flags);
8118 "allocation failed flags %llu, wanted %llu",
8121 dump_space_info(fs_info, sinfo, num_bytes, 1);
8128 static int __btrfs_free_reserved_extent(struct btrfs_fs_info *fs_info,
8130 int pin, int delalloc)
8132 struct btrfs_block_group_cache *cache;
8135 cache = btrfs_lookup_block_group(fs_info, start);
8137 btrfs_err(fs_info, "Unable to find block group for %llu",
8143 pin_down_extent(cache, start, len, 1);
8145 if (btrfs_test_opt(fs_info, DISCARD))
8146 ret = btrfs_discard_extent(fs_info, start, len, NULL);
8147 btrfs_add_free_space(cache, start, len);
8148 btrfs_free_reserved_bytes(cache, len, delalloc);
8149 trace_btrfs_reserved_extent_free(fs_info, start, len);
8152 btrfs_put_block_group(cache);
8156 int btrfs_free_reserved_extent(struct btrfs_fs_info *fs_info,
8157 u64 start, u64 len, int delalloc)
8159 return __btrfs_free_reserved_extent(fs_info, start, len, 0, delalloc);
8162 int btrfs_free_and_pin_reserved_extent(struct btrfs_fs_info *fs_info,
8165 return __btrfs_free_reserved_extent(fs_info, start, len, 1, 0);
8168 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
8169 u64 parent, u64 root_objectid,
8170 u64 flags, u64 owner, u64 offset,
8171 struct btrfs_key *ins, int ref_mod)
8173 struct btrfs_fs_info *fs_info = trans->fs_info;
8175 struct btrfs_extent_item *extent_item;
8176 struct btrfs_extent_inline_ref *iref;
8177 struct btrfs_path *path;
8178 struct extent_buffer *leaf;
8183 type = BTRFS_SHARED_DATA_REF_KEY;
8185 type = BTRFS_EXTENT_DATA_REF_KEY;
8187 size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type);
8189 path = btrfs_alloc_path();
8193 path->leave_spinning = 1;
8194 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
8197 btrfs_free_path(path);
8201 leaf = path->nodes[0];
8202 extent_item = btrfs_item_ptr(leaf, path->slots[0],
8203 struct btrfs_extent_item);
8204 btrfs_set_extent_refs(leaf, extent_item, ref_mod);
8205 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
8206 btrfs_set_extent_flags(leaf, extent_item,
8207 flags | BTRFS_EXTENT_FLAG_DATA);
8209 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
8210 btrfs_set_extent_inline_ref_type(leaf, iref, type);
8212 struct btrfs_shared_data_ref *ref;
8213 ref = (struct btrfs_shared_data_ref *)(iref + 1);
8214 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
8215 btrfs_set_shared_data_ref_count(leaf, ref, ref_mod);
8217 struct btrfs_extent_data_ref *ref;
8218 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
8219 btrfs_set_extent_data_ref_root(leaf, ref, root_objectid);
8220 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
8221 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
8222 btrfs_set_extent_data_ref_count(leaf, ref, ref_mod);
8225 btrfs_mark_buffer_dirty(path->nodes[0]);
8226 btrfs_free_path(path);
8228 ret = remove_from_free_space_tree(trans, ins->objectid, ins->offset);
8232 ret = update_block_group(trans, ins->objectid, ins->offset, 1);
8233 if (ret) { /* -ENOENT, logic error */
8234 btrfs_err(fs_info, "update block group failed for %llu %llu",
8235 ins->objectid, ins->offset);
8238 trace_btrfs_reserved_extent_alloc(fs_info, ins->objectid, ins->offset);
8242 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
8243 struct btrfs_delayed_ref_node *node,
8244 struct btrfs_delayed_extent_op *extent_op)
8246 struct btrfs_fs_info *fs_info = trans->fs_info;
8248 struct btrfs_extent_item *extent_item;
8249 struct btrfs_key extent_key;
8250 struct btrfs_tree_block_info *block_info;
8251 struct btrfs_extent_inline_ref *iref;
8252 struct btrfs_path *path;
8253 struct extent_buffer *leaf;
8254 struct btrfs_delayed_tree_ref *ref;
8255 u32 size = sizeof(*extent_item) + sizeof(*iref);
8257 u64 flags = extent_op->flags_to_set;
8258 bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
8260 ref = btrfs_delayed_node_to_tree_ref(node);
8262 extent_key.objectid = node->bytenr;
8263 if (skinny_metadata) {
8264 extent_key.offset = ref->level;
8265 extent_key.type = BTRFS_METADATA_ITEM_KEY;
8266 num_bytes = fs_info->nodesize;
8268 extent_key.offset = node->num_bytes;
8269 extent_key.type = BTRFS_EXTENT_ITEM_KEY;
8270 size += sizeof(*block_info);
8271 num_bytes = node->num_bytes;
8274 path = btrfs_alloc_path();
8278 path->leave_spinning = 1;
8279 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
8282 btrfs_free_path(path);
8286 leaf = path->nodes[0];
8287 extent_item = btrfs_item_ptr(leaf, path->slots[0],
8288 struct btrfs_extent_item);
8289 btrfs_set_extent_refs(leaf, extent_item, 1);
8290 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
8291 btrfs_set_extent_flags(leaf, extent_item,
8292 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
8294 if (skinny_metadata) {
8295 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
8297 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
8298 btrfs_set_tree_block_key(leaf, block_info, &extent_op->key);
8299 btrfs_set_tree_block_level(leaf, block_info, ref->level);
8300 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
8303 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY) {
8304 BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF));
8305 btrfs_set_extent_inline_ref_type(leaf, iref,
8306 BTRFS_SHARED_BLOCK_REF_KEY);
8307 btrfs_set_extent_inline_ref_offset(leaf, iref, ref->parent);
8309 btrfs_set_extent_inline_ref_type(leaf, iref,
8310 BTRFS_TREE_BLOCK_REF_KEY);
8311 btrfs_set_extent_inline_ref_offset(leaf, iref, ref->root);
8314 btrfs_mark_buffer_dirty(leaf);
8315 btrfs_free_path(path);
8317 ret = remove_from_free_space_tree(trans, extent_key.objectid,
8322 ret = update_block_group(trans, extent_key.objectid,
8323 fs_info->nodesize, 1);
8324 if (ret) { /* -ENOENT, logic error */
8325 btrfs_err(fs_info, "update block group failed for %llu %llu",
8326 extent_key.objectid, extent_key.offset);
8330 trace_btrfs_reserved_extent_alloc(fs_info, extent_key.objectid,
8335 int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
8336 struct btrfs_root *root, u64 owner,
8337 u64 offset, u64 ram_bytes,
8338 struct btrfs_key *ins)
8340 struct btrfs_ref generic_ref = { 0 };
8343 BUG_ON(root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID);
8345 btrfs_init_generic_ref(&generic_ref, BTRFS_ADD_DELAYED_EXTENT,
8346 ins->objectid, ins->offset, 0);
8347 btrfs_init_data_ref(&generic_ref, root->root_key.objectid, owner, offset);
8348 btrfs_ref_tree_mod(root->fs_info, &generic_ref);
8349 ret = btrfs_add_delayed_data_ref(trans, &generic_ref,
8350 ram_bytes, NULL, NULL);
8355 * this is used by the tree logging recovery code. It records that
8356 * an extent has been allocated and makes sure to clear the free
8357 * space cache bits as well
8359 int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
8360 u64 root_objectid, u64 owner, u64 offset,
8361 struct btrfs_key *ins)
8363 struct btrfs_fs_info *fs_info = trans->fs_info;
8365 struct btrfs_block_group_cache *block_group;
8366 struct btrfs_space_info *space_info;
8369 * Mixed block groups will exclude before processing the log so we only
8370 * need to do the exclude dance if this fs isn't mixed.
8372 if (!btrfs_fs_incompat(fs_info, MIXED_GROUPS)) {
8373 ret = __exclude_logged_extent(fs_info, ins->objectid,
8379 block_group = btrfs_lookup_block_group(fs_info, ins->objectid);
8383 space_info = block_group->space_info;
8384 spin_lock(&space_info->lock);
8385 spin_lock(&block_group->lock);
8386 space_info->bytes_reserved += ins->offset;
8387 block_group->reserved += ins->offset;
8388 spin_unlock(&block_group->lock);
8389 spin_unlock(&space_info->lock);
8391 ret = alloc_reserved_file_extent(trans, 0, root_objectid, 0, owner,
8393 btrfs_put_block_group(block_group);
8397 static struct extent_buffer *
8398 btrfs_init_new_buffer(struct btrfs_trans_handle *trans, struct btrfs_root *root,
8399 u64 bytenr, int level, u64 owner)
8401 struct btrfs_fs_info *fs_info = root->fs_info;
8402 struct extent_buffer *buf;
8404 buf = btrfs_find_create_tree_block(fs_info, bytenr);
8409 * Extra safety check in case the extent tree is corrupted and extent
8410 * allocator chooses to use a tree block which is already used and
8413 if (buf->lock_owner == current->pid) {
8414 btrfs_err_rl(fs_info,
8415 "tree block %llu owner %llu already locked by pid=%d, extent tree corruption detected",
8416 buf->start, btrfs_header_owner(buf), current->pid);
8417 free_extent_buffer(buf);
8418 return ERR_PTR(-EUCLEAN);
8421 btrfs_set_buffer_lockdep_class(root->root_key.objectid, buf, level);
8422 btrfs_tree_lock(buf);
8423 btrfs_clean_tree_block(buf);
8424 clear_bit(EXTENT_BUFFER_STALE, &buf->bflags);
8426 btrfs_set_lock_blocking_write(buf);
8427 set_extent_buffer_uptodate(buf);
8429 memzero_extent_buffer(buf, 0, sizeof(struct btrfs_header));
8430 btrfs_set_header_level(buf, level);
8431 btrfs_set_header_bytenr(buf, buf->start);
8432 btrfs_set_header_generation(buf, trans->transid);
8433 btrfs_set_header_backref_rev(buf, BTRFS_MIXED_BACKREF_REV);
8434 btrfs_set_header_owner(buf, owner);
8435 write_extent_buffer_fsid(buf, fs_info->fs_devices->metadata_uuid);
8436 write_extent_buffer_chunk_tree_uuid(buf, fs_info->chunk_tree_uuid);
8437 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
8438 buf->log_index = root->log_transid % 2;
8440 * we allow two log transactions at a time, use different
8441 * EXTENT bit to differentiate dirty pages.
8443 if (buf->log_index == 0)
8444 set_extent_dirty(&root->dirty_log_pages, buf->start,
8445 buf->start + buf->len - 1, GFP_NOFS);
8447 set_extent_new(&root->dirty_log_pages, buf->start,
8448 buf->start + buf->len - 1);
8450 buf->log_index = -1;
8451 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
8452 buf->start + buf->len - 1, GFP_NOFS);
8454 trans->dirty = true;
8455 /* this returns a buffer locked for blocking */
8459 static struct btrfs_block_rsv *
8460 use_block_rsv(struct btrfs_trans_handle *trans,
8461 struct btrfs_root *root, u32 blocksize)
8463 struct btrfs_fs_info *fs_info = root->fs_info;
8464 struct btrfs_block_rsv *block_rsv;
8465 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
8467 bool global_updated = false;
8469 block_rsv = get_block_rsv(trans, root);
8471 if (unlikely(block_rsv->size == 0))
8474 ret = block_rsv_use_bytes(block_rsv, blocksize);
8478 if (block_rsv->failfast)
8479 return ERR_PTR(ret);
8481 if (block_rsv->type == BTRFS_BLOCK_RSV_GLOBAL && !global_updated) {
8482 global_updated = true;
8483 update_global_block_rsv(fs_info);
8488 * The global reserve still exists to save us from ourselves, so don't
8489 * warn_on if we are short on our delayed refs reserve.
8491 if (block_rsv->type != BTRFS_BLOCK_RSV_DELREFS &&
8492 btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
8493 static DEFINE_RATELIMIT_STATE(_rs,
8494 DEFAULT_RATELIMIT_INTERVAL * 10,
8495 /*DEFAULT_RATELIMIT_BURST*/ 1);
8496 if (__ratelimit(&_rs))
8498 "BTRFS: block rsv returned %d\n", ret);
8501 ret = reserve_metadata_bytes(root, block_rsv, blocksize,
8502 BTRFS_RESERVE_NO_FLUSH);
8506 * If we couldn't reserve metadata bytes try and use some from
8507 * the global reserve if its space type is the same as the global
8510 if (block_rsv->type != BTRFS_BLOCK_RSV_GLOBAL &&
8511 block_rsv->space_info == global_rsv->space_info) {
8512 ret = block_rsv_use_bytes(global_rsv, blocksize);
8516 return ERR_PTR(ret);
8519 static void unuse_block_rsv(struct btrfs_fs_info *fs_info,
8520 struct btrfs_block_rsv *block_rsv, u32 blocksize)
8522 block_rsv_add_bytes(block_rsv, blocksize, false);
8523 block_rsv_release_bytes(fs_info, block_rsv, NULL, 0, NULL);
8527 * finds a free extent and does all the dirty work required for allocation
8528 * returns the tree buffer or an ERR_PTR on error.
8530 struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans,
8531 struct btrfs_root *root,
8532 u64 parent, u64 root_objectid,
8533 const struct btrfs_disk_key *key,
8534 int level, u64 hint,
8537 struct btrfs_fs_info *fs_info = root->fs_info;
8538 struct btrfs_key ins;
8539 struct btrfs_block_rsv *block_rsv;
8540 struct extent_buffer *buf;
8541 struct btrfs_delayed_extent_op *extent_op;
8542 struct btrfs_ref generic_ref = { 0 };
8545 u32 blocksize = fs_info->nodesize;
8546 bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
8548 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
8549 if (btrfs_is_testing(fs_info)) {
8550 buf = btrfs_init_new_buffer(trans, root, root->alloc_bytenr,
8551 level, root_objectid);
8553 root->alloc_bytenr += blocksize;
8558 block_rsv = use_block_rsv(trans, root, blocksize);
8559 if (IS_ERR(block_rsv))
8560 return ERR_CAST(block_rsv);
8562 ret = btrfs_reserve_extent(root, blocksize, blocksize, blocksize,
8563 empty_size, hint, &ins, 0, 0);
8567 buf = btrfs_init_new_buffer(trans, root, ins.objectid, level,
8571 goto out_free_reserved;
8574 if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
8576 parent = ins.objectid;
8577 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
8581 if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
8582 extent_op = btrfs_alloc_delayed_extent_op();
8588 memcpy(&extent_op->key, key, sizeof(extent_op->key));
8590 memset(&extent_op->key, 0, sizeof(extent_op->key));
8591 extent_op->flags_to_set = flags;
8592 extent_op->update_key = skinny_metadata ? false : true;
8593 extent_op->update_flags = true;
8594 extent_op->is_data = false;
8595 extent_op->level = level;
8597 btrfs_init_generic_ref(&generic_ref, BTRFS_ADD_DELAYED_EXTENT,
8598 ins.objectid, ins.offset, parent);
8599 generic_ref.real_root = root->root_key.objectid;
8600 btrfs_init_tree_ref(&generic_ref, level, root_objectid);
8601 btrfs_ref_tree_mod(fs_info, &generic_ref);
8602 ret = btrfs_add_delayed_tree_ref(trans, &generic_ref,
8603 extent_op, NULL, NULL);
8605 goto out_free_delayed;
8610 btrfs_free_delayed_extent_op(extent_op);
8612 free_extent_buffer(buf);
8614 btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 0);
8616 unuse_block_rsv(fs_info, block_rsv, blocksize);
8617 return ERR_PTR(ret);
8620 struct walk_control {
8621 u64 refs[BTRFS_MAX_LEVEL];
8622 u64 flags[BTRFS_MAX_LEVEL];
8623 struct btrfs_key update_progress;
8624 struct btrfs_key drop_progress;
8636 #define DROP_REFERENCE 1
8637 #define UPDATE_BACKREF 2
8639 static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
8640 struct btrfs_root *root,
8641 struct walk_control *wc,
8642 struct btrfs_path *path)
8644 struct btrfs_fs_info *fs_info = root->fs_info;
8650 struct btrfs_key key;
8651 struct extent_buffer *eb;
8656 if (path->slots[wc->level] < wc->reada_slot) {
8657 wc->reada_count = wc->reada_count * 2 / 3;
8658 wc->reada_count = max(wc->reada_count, 2);
8660 wc->reada_count = wc->reada_count * 3 / 2;
8661 wc->reada_count = min_t(int, wc->reada_count,
8662 BTRFS_NODEPTRS_PER_BLOCK(fs_info));
8665 eb = path->nodes[wc->level];
8666 nritems = btrfs_header_nritems(eb);
8668 for (slot = path->slots[wc->level]; slot < nritems; slot++) {
8669 if (nread >= wc->reada_count)
8673 bytenr = btrfs_node_blockptr(eb, slot);
8674 generation = btrfs_node_ptr_generation(eb, slot);
8676 if (slot == path->slots[wc->level])
8679 if (wc->stage == UPDATE_BACKREF &&
8680 generation <= root->root_key.offset)
8683 /* We don't lock the tree block, it's OK to be racy here */
8684 ret = btrfs_lookup_extent_info(trans, fs_info, bytenr,
8685 wc->level - 1, 1, &refs,
8687 /* We don't care about errors in readahead. */
8692 if (wc->stage == DROP_REFERENCE) {
8696 if (wc->level == 1 &&
8697 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
8699 if (!wc->update_ref ||
8700 generation <= root->root_key.offset)
8702 btrfs_node_key_to_cpu(eb, &key, slot);
8703 ret = btrfs_comp_cpu_keys(&key,
8704 &wc->update_progress);
8708 if (wc->level == 1 &&
8709 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
8713 readahead_tree_block(fs_info, bytenr);
8716 wc->reada_slot = slot;
8720 * helper to process tree block while walking down the tree.
8722 * when wc->stage == UPDATE_BACKREF, this function updates
8723 * back refs for pointers in the block.
8725 * NOTE: return value 1 means we should stop walking down.
8727 static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
8728 struct btrfs_root *root,
8729 struct btrfs_path *path,
8730 struct walk_control *wc, int lookup_info)
8732 struct btrfs_fs_info *fs_info = root->fs_info;
8733 int level = wc->level;
8734 struct extent_buffer *eb = path->nodes[level];
8735 u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF;
8738 if (wc->stage == UPDATE_BACKREF &&
8739 btrfs_header_owner(eb) != root->root_key.objectid)
8743 * when reference count of tree block is 1, it won't increase
8744 * again. once full backref flag is set, we never clear it.
8747 ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
8748 (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag)))) {
8749 BUG_ON(!path->locks[level]);
8750 ret = btrfs_lookup_extent_info(trans, fs_info,
8751 eb->start, level, 1,
8754 BUG_ON(ret == -ENOMEM);
8757 BUG_ON(wc->refs[level] == 0);
8760 if (wc->stage == DROP_REFERENCE) {
8761 if (wc->refs[level] > 1)
8764 if (path->locks[level] && !wc->keep_locks) {
8765 btrfs_tree_unlock_rw(eb, path->locks[level]);
8766 path->locks[level] = 0;
8771 /* wc->stage == UPDATE_BACKREF */
8772 if (!(wc->flags[level] & flag)) {
8773 BUG_ON(!path->locks[level]);
8774 ret = btrfs_inc_ref(trans, root, eb, 1);
8775 BUG_ON(ret); /* -ENOMEM */
8776 ret = btrfs_dec_ref(trans, root, eb, 0);
8777 BUG_ON(ret); /* -ENOMEM */
8778 ret = btrfs_set_disk_extent_flags(trans, eb->start,
8780 btrfs_header_level(eb), 0);
8781 BUG_ON(ret); /* -ENOMEM */
8782 wc->flags[level] |= flag;
8786 * the block is shared by multiple trees, so it's not good to
8787 * keep the tree lock
8789 if (path->locks[level] && level > 0) {
8790 btrfs_tree_unlock_rw(eb, path->locks[level]);
8791 path->locks[level] = 0;
8797 * This is used to verify a ref exists for this root to deal with a bug where we
8798 * would have a drop_progress key that hadn't been updated properly.
8800 static int check_ref_exists(struct btrfs_trans_handle *trans,
8801 struct btrfs_root *root, u64 bytenr, u64 parent,
8804 struct btrfs_path *path;
8805 struct btrfs_extent_inline_ref *iref;
8808 path = btrfs_alloc_path();
8812 ret = lookup_extent_backref(trans, path, &iref, bytenr,
8813 root->fs_info->nodesize, parent,
8814 root->root_key.objectid, level, 0);
8815 btrfs_free_path(path);
8824 * helper to process tree block pointer.
8826 * when wc->stage == DROP_REFERENCE, this function checks
8827 * reference count of the block pointed to. if the block
8828 * is shared and we need update back refs for the subtree
8829 * rooted at the block, this function changes wc->stage to
8830 * UPDATE_BACKREF. if the block is shared and there is no
8831 * need to update back, this function drops the reference
8834 * NOTE: return value 1 means we should stop walking down.
8836 static noinline int do_walk_down(struct btrfs_trans_handle *trans,
8837 struct btrfs_root *root,
8838 struct btrfs_path *path,
8839 struct walk_control *wc, int *lookup_info)
8841 struct btrfs_fs_info *fs_info = root->fs_info;
8845 struct btrfs_key key;
8846 struct btrfs_key first_key;
8847 struct btrfs_ref ref = { 0 };
8848 struct extent_buffer *next;
8849 int level = wc->level;
8852 bool need_account = false;
8854 generation = btrfs_node_ptr_generation(path->nodes[level],
8855 path->slots[level]);
8857 * if the lower level block was created before the snapshot
8858 * was created, we know there is no need to update back refs
8861 if (wc->stage == UPDATE_BACKREF &&
8862 generation <= root->root_key.offset) {
8867 bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]);
8868 btrfs_node_key_to_cpu(path->nodes[level], &first_key,
8869 path->slots[level]);
8871 next = find_extent_buffer(fs_info, bytenr);
8873 next = btrfs_find_create_tree_block(fs_info, bytenr);
8875 return PTR_ERR(next);
8877 btrfs_set_buffer_lockdep_class(root->root_key.objectid, next,
8881 btrfs_tree_lock(next);
8882 btrfs_set_lock_blocking_write(next);
8884 ret = btrfs_lookup_extent_info(trans, fs_info, bytenr, level - 1, 1,
8885 &wc->refs[level - 1],
8886 &wc->flags[level - 1]);
8890 if (unlikely(wc->refs[level - 1] == 0)) {
8891 btrfs_err(fs_info, "Missing references.");
8897 if (wc->stage == DROP_REFERENCE) {
8898 if (wc->refs[level - 1] > 1) {
8899 need_account = true;
8901 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
8904 if (!wc->update_ref ||
8905 generation <= root->root_key.offset)
8908 btrfs_node_key_to_cpu(path->nodes[level], &key,
8909 path->slots[level]);
8910 ret = btrfs_comp_cpu_keys(&key, &wc->update_progress);
8914 wc->stage = UPDATE_BACKREF;
8915 wc->shared_level = level - 1;
8919 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
8923 if (!btrfs_buffer_uptodate(next, generation, 0)) {
8924 btrfs_tree_unlock(next);
8925 free_extent_buffer(next);
8931 if (reada && level == 1)
8932 reada_walk_down(trans, root, wc, path);
8933 next = read_tree_block(fs_info, bytenr, generation, level - 1,
8936 return PTR_ERR(next);
8937 } else if (!extent_buffer_uptodate(next)) {
8938 free_extent_buffer(next);
8941 btrfs_tree_lock(next);
8942 btrfs_set_lock_blocking_write(next);
8946 ASSERT(level == btrfs_header_level(next));
8947 if (level != btrfs_header_level(next)) {
8948 btrfs_err(root->fs_info, "mismatched level");
8952 path->nodes[level] = next;
8953 path->slots[level] = 0;
8954 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
8960 wc->refs[level - 1] = 0;
8961 wc->flags[level - 1] = 0;
8962 if (wc->stage == DROP_REFERENCE) {
8963 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
8964 parent = path->nodes[level]->start;
8966 ASSERT(root->root_key.objectid ==
8967 btrfs_header_owner(path->nodes[level]));
8968 if (root->root_key.objectid !=
8969 btrfs_header_owner(path->nodes[level])) {
8970 btrfs_err(root->fs_info,
8971 "mismatched block owner");
8979 * If we had a drop_progress we need to verify the refs are set
8980 * as expected. If we find our ref then we know that from here
8981 * on out everything should be correct, and we can clear the
8984 if (wc->restarted) {
8985 ret = check_ref_exists(trans, root, bytenr, parent,
8996 * Reloc tree doesn't contribute to qgroup numbers, and we have
8997 * already accounted them at merge time (replace_path),
8998 * thus we could skip expensive subtree trace here.
9000 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID &&
9002 ret = btrfs_qgroup_trace_subtree(trans, next,
9003 generation, level - 1);
9005 btrfs_err_rl(fs_info,
9006 "Error %d accounting shared subtree. Quota is out of sync, rescan required.",
9012 * We need to update the next key in our walk control so we can
9013 * update the drop_progress key accordingly. We don't care if
9014 * find_next_key doesn't find a key because that means we're at
9015 * the end and are going to clean up now.
9017 wc->drop_level = level;
9018 find_next_key(path, level, &wc->drop_progress);
9020 btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, bytenr,
9021 fs_info->nodesize, parent);
9022 btrfs_init_tree_ref(&ref, level - 1, root->root_key.objectid);
9023 ret = btrfs_free_extent(trans, &ref);
9032 btrfs_tree_unlock(next);
9033 free_extent_buffer(next);
9039 * helper to process tree block while walking up the tree.
9041 * when wc->stage == DROP_REFERENCE, this function drops
9042 * reference count on the block.
9044 * when wc->stage == UPDATE_BACKREF, this function changes
9045 * wc->stage back to DROP_REFERENCE if we changed wc->stage
9046 * to UPDATE_BACKREF previously while processing the block.
9048 * NOTE: return value 1 means we should stop walking up.
9050 static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
9051 struct btrfs_root *root,
9052 struct btrfs_path *path,
9053 struct walk_control *wc)
9055 struct btrfs_fs_info *fs_info = root->fs_info;
9057 int level = wc->level;
9058 struct extent_buffer *eb = path->nodes[level];
9061 if (wc->stage == UPDATE_BACKREF) {
9062 BUG_ON(wc->shared_level < level);
9063 if (level < wc->shared_level)
9066 ret = find_next_key(path, level + 1, &wc->update_progress);
9070 wc->stage = DROP_REFERENCE;
9071 wc->shared_level = -1;
9072 path->slots[level] = 0;
9075 * check reference count again if the block isn't locked.
9076 * we should start walking down the tree again if reference
9079 if (!path->locks[level]) {
9081 btrfs_tree_lock(eb);
9082 btrfs_set_lock_blocking_write(eb);
9083 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
9085 ret = btrfs_lookup_extent_info(trans, fs_info,
9086 eb->start, level, 1,
9090 btrfs_tree_unlock_rw(eb, path->locks[level]);
9091 path->locks[level] = 0;
9094 BUG_ON(wc->refs[level] == 0);
9095 if (wc->refs[level] == 1) {
9096 btrfs_tree_unlock_rw(eb, path->locks[level]);
9097 path->locks[level] = 0;
9103 /* wc->stage == DROP_REFERENCE */
9104 BUG_ON(wc->refs[level] > 1 && !path->locks[level]);
9106 if (wc->refs[level] == 1) {
9108 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
9109 ret = btrfs_dec_ref(trans, root, eb, 1);
9111 ret = btrfs_dec_ref(trans, root, eb, 0);
9112 BUG_ON(ret); /* -ENOMEM */
9113 if (is_fstree(root->root_key.objectid)) {
9114 ret = btrfs_qgroup_trace_leaf_items(trans, eb);
9116 btrfs_err_rl(fs_info,
9117 "error %d accounting leaf items, quota is out of sync, rescan required",
9122 /* make block locked assertion in btrfs_clean_tree_block happy */
9123 if (!path->locks[level] &&
9124 btrfs_header_generation(eb) == trans->transid) {
9125 btrfs_tree_lock(eb);
9126 btrfs_set_lock_blocking_write(eb);
9127 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
9129 btrfs_clean_tree_block(eb);
9132 if (eb == root->node) {
9133 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
9135 else if (root->root_key.objectid != btrfs_header_owner(eb))
9136 goto owner_mismatch;
9138 if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
9139 parent = path->nodes[level + 1]->start;
9140 else if (root->root_key.objectid !=
9141 btrfs_header_owner(path->nodes[level + 1]))
9142 goto owner_mismatch;
9145 btrfs_free_tree_block(trans, root, eb, parent, wc->refs[level] == 1);
9147 wc->refs[level] = 0;
9148 wc->flags[level] = 0;
9152 btrfs_err_rl(fs_info, "unexpected tree owner, have %llu expect %llu",
9153 btrfs_header_owner(eb), root->root_key.objectid);
9157 static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
9158 struct btrfs_root *root,
9159 struct btrfs_path *path,
9160 struct walk_control *wc)
9162 int level = wc->level;
9163 int lookup_info = 1;
9166 while (level >= 0) {
9167 ret = walk_down_proc(trans, root, path, wc, lookup_info);
9174 if (path->slots[level] >=
9175 btrfs_header_nritems(path->nodes[level]))
9178 ret = do_walk_down(trans, root, path, wc, &lookup_info);
9180 path->slots[level]++;
9189 static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
9190 struct btrfs_root *root,
9191 struct btrfs_path *path,
9192 struct walk_control *wc, int max_level)
9194 int level = wc->level;
9197 path->slots[level] = btrfs_header_nritems(path->nodes[level]);
9198 while (level < max_level && path->nodes[level]) {
9200 if (path->slots[level] + 1 <
9201 btrfs_header_nritems(path->nodes[level])) {
9202 path->slots[level]++;
9205 ret = walk_up_proc(trans, root, path, wc);
9211 if (path->locks[level]) {
9212 btrfs_tree_unlock_rw(path->nodes[level],
9213 path->locks[level]);
9214 path->locks[level] = 0;
9216 free_extent_buffer(path->nodes[level]);
9217 path->nodes[level] = NULL;
9225 * drop a subvolume tree.
9227 * this function traverses the tree freeing any blocks that only
9228 * referenced by the tree.
9230 * when a shared tree block is found. this function decreases its
9231 * reference count by one. if update_ref is true, this function
9232 * also make sure backrefs for the shared block and all lower level
9233 * blocks are properly updated.
9235 * If called with for_reloc == 0, may exit early with -EAGAIN
9237 int btrfs_drop_snapshot(struct btrfs_root *root,
9238 struct btrfs_block_rsv *block_rsv, int update_ref,
9241 struct btrfs_fs_info *fs_info = root->fs_info;
9242 struct btrfs_path *path;
9243 struct btrfs_trans_handle *trans;
9244 struct btrfs_root *tree_root = fs_info->tree_root;
9245 struct btrfs_root_item *root_item = &root->root_item;
9246 struct walk_control *wc;
9247 struct btrfs_key key;
9251 bool root_dropped = false;
9253 btrfs_debug(fs_info, "Drop subvolume %llu", root->root_key.objectid);
9255 path = btrfs_alloc_path();
9261 wc = kzalloc(sizeof(*wc), GFP_NOFS);
9263 btrfs_free_path(path);
9268 trans = btrfs_start_transaction(tree_root, 0);
9269 if (IS_ERR(trans)) {
9270 err = PTR_ERR(trans);
9274 err = btrfs_run_delayed_items(trans);
9279 trans->block_rsv = block_rsv;
9282 * This will help us catch people modifying the fs tree while we're
9283 * dropping it. It is unsafe to mess with the fs tree while it's being
9284 * dropped as we unlock the root node and parent nodes as we walk down
9285 * the tree, assuming nothing will change. If something does change
9286 * then we'll have stale information and drop references to blocks we've
9289 set_bit(BTRFS_ROOT_DELETING, &root->state);
9290 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
9291 level = btrfs_header_level(root->node);
9292 path->nodes[level] = btrfs_lock_root_node(root);
9293 btrfs_set_lock_blocking_write(path->nodes[level]);
9294 path->slots[level] = 0;
9295 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
9296 memset(&wc->update_progress, 0,
9297 sizeof(wc->update_progress));
9299 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
9300 memcpy(&wc->update_progress, &key,
9301 sizeof(wc->update_progress));
9303 level = root_item->drop_level;
9305 path->lowest_level = level;
9306 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
9307 path->lowest_level = 0;
9315 * unlock our path, this is safe because only this
9316 * function is allowed to delete this snapshot
9318 btrfs_unlock_up_safe(path, 0);
9320 level = btrfs_header_level(root->node);
9322 btrfs_tree_lock(path->nodes[level]);
9323 btrfs_set_lock_blocking_write(path->nodes[level]);
9324 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
9326 ret = btrfs_lookup_extent_info(trans, fs_info,
9327 path->nodes[level]->start,
9328 level, 1, &wc->refs[level],
9334 BUG_ON(wc->refs[level] == 0);
9336 if (level == root_item->drop_level)
9339 btrfs_tree_unlock(path->nodes[level]);
9340 path->locks[level] = 0;
9341 WARN_ON(wc->refs[level] != 1);
9346 wc->restarted = test_bit(BTRFS_ROOT_DEAD_TREE, &root->state);
9348 wc->shared_level = -1;
9349 wc->stage = DROP_REFERENCE;
9350 wc->update_ref = update_ref;
9352 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(fs_info);
9356 ret = walk_down_tree(trans, root, path, wc);
9362 ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL);
9369 BUG_ON(wc->stage != DROP_REFERENCE);
9373 if (wc->stage == DROP_REFERENCE) {
9374 wc->drop_level = wc->level;
9375 btrfs_node_key_to_cpu(path->nodes[wc->drop_level],
9377 path->slots[wc->drop_level]);
9379 btrfs_cpu_key_to_disk(&root_item->drop_progress,
9380 &wc->drop_progress);
9381 root_item->drop_level = wc->drop_level;
9383 BUG_ON(wc->level == 0);
9384 if (btrfs_should_end_transaction(trans) ||
9385 (!for_reloc && btrfs_need_cleaner_sleep(fs_info))) {
9386 ret = btrfs_update_root(trans, tree_root,
9390 btrfs_abort_transaction(trans, ret);
9395 btrfs_end_transaction_throttle(trans);
9396 if (!for_reloc && btrfs_need_cleaner_sleep(fs_info)) {
9397 btrfs_debug(fs_info,
9398 "drop snapshot early exit");
9403 trans = btrfs_start_transaction(tree_root, 0);
9404 if (IS_ERR(trans)) {
9405 err = PTR_ERR(trans);
9409 trans->block_rsv = block_rsv;
9412 btrfs_release_path(path);
9416 ret = btrfs_del_root(trans, &root->root_key);
9418 btrfs_abort_transaction(trans, ret);
9423 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
9424 ret = btrfs_find_root(tree_root, &root->root_key, path,
9427 btrfs_abort_transaction(trans, ret);
9430 } else if (ret > 0) {
9431 /* if we fail to delete the orphan item this time
9432 * around, it'll get picked up the next time.
9434 * The most common failure here is just -ENOENT.
9436 btrfs_del_orphan_item(trans, tree_root,
9437 root->root_key.objectid);
9441 if (test_bit(BTRFS_ROOT_IN_RADIX, &root->state)) {
9442 btrfs_add_dropped_root(trans, root);
9444 free_extent_buffer(root->node);
9445 free_extent_buffer(root->commit_root);
9446 btrfs_put_fs_root(root);
9448 root_dropped = true;
9450 btrfs_end_transaction_throttle(trans);
9453 btrfs_free_path(path);
9456 * So if we need to stop dropping the snapshot for whatever reason we
9457 * need to make sure to add it back to the dead root list so that we
9458 * keep trying to do the work later. This also cleans up roots if we
9459 * don't have it in the radix (like when we recover after a power fail
9460 * or unmount) so we don't leak memory.
9462 if (!for_reloc && !root_dropped)
9463 btrfs_add_dead_root(root);
9464 if (err && err != -EAGAIN)
9465 btrfs_handle_fs_error(fs_info, err, NULL);
9470 * drop subtree rooted at tree block 'node'.
9472 * NOTE: this function will unlock and release tree block 'node'
9473 * only used by relocation code
9475 int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
9476 struct btrfs_root *root,
9477 struct extent_buffer *node,
9478 struct extent_buffer *parent)
9480 struct btrfs_fs_info *fs_info = root->fs_info;
9481 struct btrfs_path *path;
9482 struct walk_control *wc;
9488 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
9490 path = btrfs_alloc_path();
9494 wc = kzalloc(sizeof(*wc), GFP_NOFS);
9496 btrfs_free_path(path);
9500 btrfs_assert_tree_locked(parent);
9501 parent_level = btrfs_header_level(parent);
9502 extent_buffer_get(parent);
9503 path->nodes[parent_level] = parent;
9504 path->slots[parent_level] = btrfs_header_nritems(parent);
9506 btrfs_assert_tree_locked(node);
9507 level = btrfs_header_level(node);
9508 path->nodes[level] = node;
9509 path->slots[level] = 0;
9510 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
9512 wc->refs[parent_level] = 1;
9513 wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF;
9515 wc->shared_level = -1;
9516 wc->stage = DROP_REFERENCE;
9519 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(fs_info);
9522 wret = walk_down_tree(trans, root, path, wc);
9528 wret = walk_up_tree(trans, root, path, wc, parent_level);
9536 btrfs_free_path(path);
9540 static u64 update_block_group_flags(struct btrfs_fs_info *fs_info, u64 flags)
9546 * if restripe for this chunk_type is on pick target profile and
9547 * return, otherwise do the usual balance
9549 stripped = get_restripe_target(fs_info, flags);
9551 return extended_to_chunk(stripped);
9553 num_devices = fs_info->fs_devices->rw_devices;
9555 stripped = BTRFS_BLOCK_GROUP_RAID0 |
9556 BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6 |
9557 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
9559 if (num_devices == 1) {
9560 stripped |= BTRFS_BLOCK_GROUP_DUP;
9561 stripped = flags & ~stripped;
9563 /* turn raid0 into single device chunks */
9564 if (flags & BTRFS_BLOCK_GROUP_RAID0)
9567 /* turn mirroring into duplication */
9568 if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
9569 BTRFS_BLOCK_GROUP_RAID10))
9570 return stripped | BTRFS_BLOCK_GROUP_DUP;
9572 /* they already had raid on here, just return */
9573 if (flags & stripped)
9576 stripped |= BTRFS_BLOCK_GROUP_DUP;
9577 stripped = flags & ~stripped;
9579 /* switch duplicated blocks with raid1 */
9580 if (flags & BTRFS_BLOCK_GROUP_DUP)
9581 return stripped | BTRFS_BLOCK_GROUP_RAID1;
9583 /* this is drive concat, leave it alone */
9589 static int inc_block_group_ro(struct btrfs_block_group_cache *cache, int force)
9591 struct btrfs_space_info *sinfo = cache->space_info;
9594 u64 min_allocable_bytes;
9598 * We need some metadata space and system metadata space for
9599 * allocating chunks in some corner cases until we force to set
9600 * it to be readonly.
9603 (BTRFS_BLOCK_GROUP_SYSTEM | BTRFS_BLOCK_GROUP_METADATA)) &&
9605 min_allocable_bytes = SZ_1M;
9607 min_allocable_bytes = 0;
9609 spin_lock(&sinfo->lock);
9610 spin_lock(&cache->lock);
9618 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
9619 cache->bytes_super - btrfs_block_group_used(&cache->item);
9620 sinfo_used = btrfs_space_info_used(sinfo, true);
9622 if (sinfo_used + num_bytes + min_allocable_bytes <=
9623 sinfo->total_bytes) {
9624 sinfo->bytes_readonly += num_bytes;
9626 list_add_tail(&cache->ro_list, &sinfo->ro_bgs);
9630 spin_unlock(&cache->lock);
9631 spin_unlock(&sinfo->lock);
9632 if (ret == -ENOSPC && btrfs_test_opt(cache->fs_info, ENOSPC_DEBUG)) {
9633 btrfs_info(cache->fs_info,
9634 "unable to make block group %llu ro",
9635 cache->key.objectid);
9636 btrfs_info(cache->fs_info,
9637 "sinfo_used=%llu bg_num_bytes=%llu min_allocable=%llu",
9638 sinfo_used, num_bytes, min_allocable_bytes);
9639 dump_space_info(cache->fs_info, cache->space_info, 0, 0);
9644 int btrfs_inc_block_group_ro(struct btrfs_block_group_cache *cache)
9647 struct btrfs_fs_info *fs_info = cache->fs_info;
9648 struct btrfs_trans_handle *trans;
9653 trans = btrfs_join_transaction(fs_info->extent_root);
9655 return PTR_ERR(trans);
9658 * we're not allowed to set block groups readonly after the dirty
9659 * block groups cache has started writing. If it already started,
9660 * back off and let this transaction commit
9662 mutex_lock(&fs_info->ro_block_group_mutex);
9663 if (test_bit(BTRFS_TRANS_DIRTY_BG_RUN, &trans->transaction->flags)) {
9664 u64 transid = trans->transid;
9666 mutex_unlock(&fs_info->ro_block_group_mutex);
9667 btrfs_end_transaction(trans);
9669 ret = btrfs_wait_for_commit(fs_info, transid);
9676 * if we are changing raid levels, try to allocate a corresponding
9677 * block group with the new raid level.
9679 alloc_flags = update_block_group_flags(fs_info, cache->flags);
9680 if (alloc_flags != cache->flags) {
9681 ret = do_chunk_alloc(trans, alloc_flags,
9684 * ENOSPC is allowed here, we may have enough space
9685 * already allocated at the new raid level to
9694 ret = inc_block_group_ro(cache, 0);
9697 alloc_flags = get_alloc_profile(fs_info, cache->space_info->flags);
9698 ret = do_chunk_alloc(trans, alloc_flags, CHUNK_ALLOC_FORCE);
9701 ret = inc_block_group_ro(cache, 0);
9703 if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM) {
9704 alloc_flags = update_block_group_flags(fs_info, cache->flags);
9705 mutex_lock(&fs_info->chunk_mutex);
9706 check_system_chunk(trans, alloc_flags);
9707 mutex_unlock(&fs_info->chunk_mutex);
9709 mutex_unlock(&fs_info->ro_block_group_mutex);
9711 btrfs_end_transaction(trans);
9715 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans, u64 type)
9717 u64 alloc_flags = get_alloc_profile(trans->fs_info, type);
9719 return do_chunk_alloc(trans, alloc_flags, CHUNK_ALLOC_FORCE);
9723 * helper to account the unused space of all the readonly block group in the
9724 * space_info. takes mirrors into account.
9726 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo)
9728 struct btrfs_block_group_cache *block_group;
9732 /* It's df, we don't care if it's racy */
9733 if (list_empty(&sinfo->ro_bgs))
9736 spin_lock(&sinfo->lock);
9737 list_for_each_entry(block_group, &sinfo->ro_bgs, ro_list) {
9738 spin_lock(&block_group->lock);
9740 if (!block_group->ro) {
9741 spin_unlock(&block_group->lock);
9745 factor = btrfs_bg_type_to_factor(block_group->flags);
9746 free_bytes += (block_group->key.offset -
9747 btrfs_block_group_used(&block_group->item)) *
9750 spin_unlock(&block_group->lock);
9752 spin_unlock(&sinfo->lock);
9757 void btrfs_dec_block_group_ro(struct btrfs_block_group_cache *cache)
9759 struct btrfs_space_info *sinfo = cache->space_info;
9764 spin_lock(&sinfo->lock);
9765 spin_lock(&cache->lock);
9767 num_bytes = cache->key.offset - cache->reserved -
9768 cache->pinned - cache->bytes_super -
9769 btrfs_block_group_used(&cache->item);
9770 sinfo->bytes_readonly -= num_bytes;
9771 list_del_init(&cache->ro_list);
9773 spin_unlock(&cache->lock);
9774 spin_unlock(&sinfo->lock);
9778 * Checks to see if it's even possible to relocate this block group.
9780 * @return - -1 if it's not a good idea to relocate this block group, 0 if its
9781 * ok to go ahead and try.
9783 int btrfs_can_relocate(struct btrfs_fs_info *fs_info, u64 bytenr)
9785 struct btrfs_block_group_cache *block_group;
9786 struct btrfs_space_info *space_info;
9787 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
9788 struct btrfs_device *device;
9798 debug = btrfs_test_opt(fs_info, ENOSPC_DEBUG);
9800 block_group = btrfs_lookup_block_group(fs_info, bytenr);
9802 /* odd, couldn't find the block group, leave it alone */
9806 "can't find block group for bytenr %llu",
9811 min_free = btrfs_block_group_used(&block_group->item);
9813 /* no bytes used, we're good */
9817 space_info = block_group->space_info;
9818 spin_lock(&space_info->lock);
9820 full = space_info->full;
9823 * if this is the last block group we have in this space, we can't
9824 * relocate it unless we're able to allocate a new chunk below.
9826 * Otherwise, we need to make sure we have room in the space to handle
9827 * all of the extents from this block group. If we can, we're good
9829 if ((space_info->total_bytes != block_group->key.offset) &&
9830 (btrfs_space_info_used(space_info, false) + min_free <
9831 space_info->total_bytes)) {
9832 spin_unlock(&space_info->lock);
9835 spin_unlock(&space_info->lock);
9838 * ok we don't have enough space, but maybe we have free space on our
9839 * devices to allocate new chunks for relocation, so loop through our
9840 * alloc devices and guess if we have enough space. if this block
9841 * group is going to be restriped, run checks against the target
9842 * profile instead of the current one.
9854 target = get_restripe_target(fs_info, block_group->flags);
9856 index = btrfs_bg_flags_to_raid_index(extended_to_chunk(target));
9859 * this is just a balance, so if we were marked as full
9860 * we know there is no space for a new chunk
9865 "no space to alloc new chunk for block group %llu",
9866 block_group->key.objectid);
9870 index = btrfs_bg_flags_to_raid_index(block_group->flags);
9873 if (index == BTRFS_RAID_RAID10) {
9877 } else if (index == BTRFS_RAID_RAID1) {
9879 } else if (index == BTRFS_RAID_DUP) {
9882 } else if (index == BTRFS_RAID_RAID0) {
9883 dev_min = fs_devices->rw_devices;
9884 min_free = div64_u64(min_free, dev_min);
9887 mutex_lock(&fs_info->chunk_mutex);
9888 list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
9892 * check to make sure we can actually find a chunk with enough
9893 * space to fit our block group in.
9895 if (device->total_bytes > device->bytes_used + min_free &&
9896 !test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
9897 ret = find_free_dev_extent(device, min_free,
9902 if (dev_nr >= dev_min)
9908 if (debug && ret == -1)
9910 "no space to allocate a new chunk for block group %llu",
9911 block_group->key.objectid);
9912 mutex_unlock(&fs_info->chunk_mutex);
9914 btrfs_put_block_group(block_group);
9918 static int find_first_block_group(struct btrfs_fs_info *fs_info,
9919 struct btrfs_path *path,
9920 struct btrfs_key *key)
9922 struct btrfs_root *root = fs_info->extent_root;
9924 struct btrfs_key found_key;
9925 struct extent_buffer *leaf;
9926 struct btrfs_block_group_item bg;
9930 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
9935 slot = path->slots[0];
9936 leaf = path->nodes[0];
9937 if (slot >= btrfs_header_nritems(leaf)) {
9938 ret = btrfs_next_leaf(root, path);
9945 btrfs_item_key_to_cpu(leaf, &found_key, slot);
9947 if (found_key.objectid >= key->objectid &&
9948 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
9949 struct extent_map_tree *em_tree;
9950 struct extent_map *em;
9952 em_tree = &root->fs_info->mapping_tree.map_tree;
9953 read_lock(&em_tree->lock);
9954 em = lookup_extent_mapping(em_tree, found_key.objectid,
9956 read_unlock(&em_tree->lock);
9959 "logical %llu len %llu found bg but no related chunk",
9960 found_key.objectid, found_key.offset);
9962 } else if (em->start != found_key.objectid ||
9963 em->len != found_key.offset) {
9965 "block group %llu len %llu mismatch with chunk %llu len %llu",
9966 found_key.objectid, found_key.offset,
9967 em->start, em->len);
9970 read_extent_buffer(leaf, &bg,
9971 btrfs_item_ptr_offset(leaf, slot),
9973 flags = btrfs_block_group_flags(&bg) &
9974 BTRFS_BLOCK_GROUP_TYPE_MASK;
9976 if (flags != (em->map_lookup->type &
9977 BTRFS_BLOCK_GROUP_TYPE_MASK)) {
9979 "block group %llu len %llu type flags 0x%llx mismatch with chunk type flags 0x%llx",
9981 found_key.offset, flags,
9982 (BTRFS_BLOCK_GROUP_TYPE_MASK &
9983 em->map_lookup->type));
9989 free_extent_map(em);
9998 void btrfs_put_block_group_cache(struct btrfs_fs_info *info)
10000 struct btrfs_block_group_cache *block_group;
10004 struct inode *inode;
10006 block_group = btrfs_lookup_first_block_group(info, last);
10007 while (block_group) {
10008 wait_block_group_cache_done(block_group);
10009 spin_lock(&block_group->lock);
10010 if (block_group->iref)
10012 spin_unlock(&block_group->lock);
10013 block_group = next_block_group(block_group);
10015 if (!block_group) {
10022 inode = block_group->inode;
10023 block_group->iref = 0;
10024 block_group->inode = NULL;
10025 spin_unlock(&block_group->lock);
10026 ASSERT(block_group->io_ctl.inode == NULL);
10028 last = block_group->key.objectid + block_group->key.offset;
10029 btrfs_put_block_group(block_group);
10034 * Must be called only after stopping all workers, since we could have block
10035 * group caching kthreads running, and therefore they could race with us if we
10036 * freed the block groups before stopping them.
10038 int btrfs_free_block_groups(struct btrfs_fs_info *info)
10040 struct btrfs_block_group_cache *block_group;
10041 struct btrfs_space_info *space_info;
10042 struct btrfs_caching_control *caching_ctl;
10045 down_write(&info->commit_root_sem);
10046 while (!list_empty(&info->caching_block_groups)) {
10047 caching_ctl = list_entry(info->caching_block_groups.next,
10048 struct btrfs_caching_control, list);
10049 list_del(&caching_ctl->list);
10050 put_caching_control(caching_ctl);
10052 up_write(&info->commit_root_sem);
10054 spin_lock(&info->unused_bgs_lock);
10055 while (!list_empty(&info->unused_bgs)) {
10056 block_group = list_first_entry(&info->unused_bgs,
10057 struct btrfs_block_group_cache,
10059 list_del_init(&block_group->bg_list);
10060 btrfs_put_block_group(block_group);
10062 spin_unlock(&info->unused_bgs_lock);
10064 spin_lock(&info->block_group_cache_lock);
10065 while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
10066 block_group = rb_entry(n, struct btrfs_block_group_cache,
10068 rb_erase(&block_group->cache_node,
10069 &info->block_group_cache_tree);
10070 RB_CLEAR_NODE(&block_group->cache_node);
10071 spin_unlock(&info->block_group_cache_lock);
10073 down_write(&block_group->space_info->groups_sem);
10074 list_del(&block_group->list);
10075 up_write(&block_group->space_info->groups_sem);
10078 * We haven't cached this block group, which means we could
10079 * possibly have excluded extents on this block group.
10081 if (block_group->cached == BTRFS_CACHE_NO ||
10082 block_group->cached == BTRFS_CACHE_ERROR)
10083 free_excluded_extents(block_group);
10085 btrfs_remove_free_space_cache(block_group);
10086 ASSERT(block_group->cached != BTRFS_CACHE_STARTED);
10087 ASSERT(list_empty(&block_group->dirty_list));
10088 ASSERT(list_empty(&block_group->io_list));
10089 ASSERT(list_empty(&block_group->bg_list));
10090 ASSERT(atomic_read(&block_group->count) == 1);
10091 btrfs_put_block_group(block_group);
10093 spin_lock(&info->block_group_cache_lock);
10095 spin_unlock(&info->block_group_cache_lock);
10097 /* now that all the block groups are freed, go through and
10098 * free all the space_info structs. This is only called during
10099 * the final stages of unmount, and so we know nobody is
10100 * using them. We call synchronize_rcu() once before we start,
10101 * just to be on the safe side.
10105 release_global_block_rsv(info);
10107 while (!list_empty(&info->space_info)) {
10110 space_info = list_entry(info->space_info.next,
10111 struct btrfs_space_info,
10115 * Do not hide this behind enospc_debug, this is actually
10116 * important and indicates a real bug if this happens.
10118 if (WARN_ON(space_info->bytes_pinned > 0 ||
10119 space_info->bytes_reserved > 0 ||
10120 space_info->bytes_may_use > 0))
10121 dump_space_info(info, space_info, 0, 0);
10122 list_del(&space_info->list);
10123 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
10124 struct kobject *kobj;
10125 kobj = space_info->block_group_kobjs[i];
10126 space_info->block_group_kobjs[i] = NULL;
10132 kobject_del(&space_info->kobj);
10133 kobject_put(&space_info->kobj);
10138 /* link_block_group will queue up kobjects to add when we're reclaim-safe */
10139 void btrfs_add_raid_kobjects(struct btrfs_fs_info *fs_info)
10141 struct btrfs_space_info *space_info;
10142 struct raid_kobject *rkobj;
10147 spin_lock(&fs_info->pending_raid_kobjs_lock);
10148 list_splice_init(&fs_info->pending_raid_kobjs, &list);
10149 spin_unlock(&fs_info->pending_raid_kobjs_lock);
10151 list_for_each_entry(rkobj, &list, list) {
10152 space_info = __find_space_info(fs_info, rkobj->flags);
10153 index = btrfs_bg_flags_to_raid_index(rkobj->flags);
10155 ret = kobject_add(&rkobj->kobj, &space_info->kobj,
10156 "%s", get_raid_name(index));
10158 kobject_put(&rkobj->kobj);
10163 btrfs_warn(fs_info,
10164 "failed to add kobject for block cache, ignoring");
10167 static void link_block_group(struct btrfs_block_group_cache *cache)
10169 struct btrfs_space_info *space_info = cache->space_info;
10170 struct btrfs_fs_info *fs_info = cache->fs_info;
10171 int index = btrfs_bg_flags_to_raid_index(cache->flags);
10172 bool first = false;
10174 down_write(&space_info->groups_sem);
10175 if (list_empty(&space_info->block_groups[index]))
10177 list_add_tail(&cache->list, &space_info->block_groups[index]);
10178 up_write(&space_info->groups_sem);
10181 struct raid_kobject *rkobj = kzalloc(sizeof(*rkobj), GFP_NOFS);
10183 btrfs_warn(cache->fs_info,
10184 "couldn't alloc memory for raid level kobject");
10187 rkobj->flags = cache->flags;
10188 kobject_init(&rkobj->kobj, &btrfs_raid_ktype);
10190 spin_lock(&fs_info->pending_raid_kobjs_lock);
10191 list_add_tail(&rkobj->list, &fs_info->pending_raid_kobjs);
10192 spin_unlock(&fs_info->pending_raid_kobjs_lock);
10193 space_info->block_group_kobjs[index] = &rkobj->kobj;
10197 static struct btrfs_block_group_cache *
10198 btrfs_create_block_group_cache(struct btrfs_fs_info *fs_info,
10199 u64 start, u64 size)
10201 struct btrfs_block_group_cache *cache;
10203 cache = kzalloc(sizeof(*cache), GFP_NOFS);
10207 cache->free_space_ctl = kzalloc(sizeof(*cache->free_space_ctl),
10209 if (!cache->free_space_ctl) {
10214 cache->key.objectid = start;
10215 cache->key.offset = size;
10216 cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
10218 cache->fs_info = fs_info;
10219 cache->full_stripe_len = btrfs_full_stripe_len(fs_info, start);
10220 set_free_space_tree_thresholds(cache);
10222 atomic_set(&cache->count, 1);
10223 spin_lock_init(&cache->lock);
10224 init_rwsem(&cache->data_rwsem);
10225 INIT_LIST_HEAD(&cache->list);
10226 INIT_LIST_HEAD(&cache->cluster_list);
10227 INIT_LIST_HEAD(&cache->bg_list);
10228 INIT_LIST_HEAD(&cache->ro_list);
10229 INIT_LIST_HEAD(&cache->dirty_list);
10230 INIT_LIST_HEAD(&cache->io_list);
10231 btrfs_init_free_space_ctl(cache);
10232 atomic_set(&cache->trimming, 0);
10233 mutex_init(&cache->free_space_lock);
10234 btrfs_init_full_stripe_locks_tree(&cache->full_stripe_locks_root);
10241 * Iterate all chunks and verify that each of them has the corresponding block
10244 static int check_chunk_block_group_mappings(struct btrfs_fs_info *fs_info)
10246 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
10247 struct extent_map *em;
10248 struct btrfs_block_group_cache *bg;
10253 read_lock(&map_tree->map_tree.lock);
10255 * lookup_extent_mapping will return the first extent map
10256 * intersecting the range, so setting @len to 1 is enough to
10257 * get the first chunk.
10259 em = lookup_extent_mapping(&map_tree->map_tree, start, 1);
10260 read_unlock(&map_tree->map_tree.lock);
10264 bg = btrfs_lookup_block_group(fs_info, em->start);
10267 "chunk start=%llu len=%llu doesn't have corresponding block group",
10268 em->start, em->len);
10270 free_extent_map(em);
10273 if (bg->key.objectid != em->start ||
10274 bg->key.offset != em->len ||
10275 (bg->flags & BTRFS_BLOCK_GROUP_TYPE_MASK) !=
10276 (em->map_lookup->type & BTRFS_BLOCK_GROUP_TYPE_MASK)) {
10278 "chunk start=%llu len=%llu flags=0x%llx doesn't match block group start=%llu len=%llu flags=0x%llx",
10279 em->start, em->len,
10280 em->map_lookup->type & BTRFS_BLOCK_GROUP_TYPE_MASK,
10281 bg->key.objectid, bg->key.offset,
10282 bg->flags & BTRFS_BLOCK_GROUP_TYPE_MASK);
10284 free_extent_map(em);
10285 btrfs_put_block_group(bg);
10288 start = em->start + em->len;
10289 free_extent_map(em);
10290 btrfs_put_block_group(bg);
10295 int btrfs_read_block_groups(struct btrfs_fs_info *info)
10297 struct btrfs_path *path;
10299 struct btrfs_block_group_cache *cache;
10300 struct btrfs_space_info *space_info;
10301 struct btrfs_key key;
10302 struct btrfs_key found_key;
10303 struct extent_buffer *leaf;
10304 int need_clear = 0;
10309 feature = btrfs_super_incompat_flags(info->super_copy);
10310 mixed = !!(feature & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS);
10314 key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
10315 path = btrfs_alloc_path();
10318 path->reada = READA_FORWARD;
10320 cache_gen = btrfs_super_cache_generation(info->super_copy);
10321 if (btrfs_test_opt(info, SPACE_CACHE) &&
10322 btrfs_super_generation(info->super_copy) != cache_gen)
10324 if (btrfs_test_opt(info, CLEAR_CACHE))
10328 ret = find_first_block_group(info, path, &key);
10334 leaf = path->nodes[0];
10335 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
10337 cache = btrfs_create_block_group_cache(info, found_key.objectid,
10346 * When we mount with old space cache, we need to
10347 * set BTRFS_DC_CLEAR and set dirty flag.
10349 * a) Setting 'BTRFS_DC_CLEAR' makes sure that we
10350 * truncate the old free space cache inode and
10352 * b) Setting 'dirty flag' makes sure that we flush
10353 * the new space cache info onto disk.
10355 if (btrfs_test_opt(info, SPACE_CACHE))
10356 cache->disk_cache_state = BTRFS_DC_CLEAR;
10359 read_extent_buffer(leaf, &cache->item,
10360 btrfs_item_ptr_offset(leaf, path->slots[0]),
10361 sizeof(cache->item));
10362 cache->flags = btrfs_block_group_flags(&cache->item);
10364 ((cache->flags & BTRFS_BLOCK_GROUP_METADATA) &&
10365 (cache->flags & BTRFS_BLOCK_GROUP_DATA))) {
10367 "bg %llu is a mixed block group but filesystem hasn't enabled mixed block groups",
10368 cache->key.objectid);
10373 key.objectid = found_key.objectid + found_key.offset;
10374 btrfs_release_path(path);
10377 * We need to exclude the super stripes now so that the space
10378 * info has super bytes accounted for, otherwise we'll think
10379 * we have more space than we actually do.
10381 ret = exclude_super_stripes(cache);
10384 * We may have excluded something, so call this just in
10387 free_excluded_extents(cache);
10388 btrfs_put_block_group(cache);
10393 * check for two cases, either we are full, and therefore
10394 * don't need to bother with the caching work since we won't
10395 * find any space, or we are empty, and we can just add all
10396 * the space in and be done with it. This saves us _a_lot_ of
10397 * time, particularly in the full case.
10399 if (found_key.offset == btrfs_block_group_used(&cache->item)) {
10400 cache->last_byte_to_unpin = (u64)-1;
10401 cache->cached = BTRFS_CACHE_FINISHED;
10402 free_excluded_extents(cache);
10403 } else if (btrfs_block_group_used(&cache->item) == 0) {
10404 cache->last_byte_to_unpin = (u64)-1;
10405 cache->cached = BTRFS_CACHE_FINISHED;
10406 add_new_free_space(cache, found_key.objectid,
10407 found_key.objectid +
10409 free_excluded_extents(cache);
10412 ret = btrfs_add_block_group_cache(info, cache);
10414 btrfs_remove_free_space_cache(cache);
10415 btrfs_put_block_group(cache);
10419 trace_btrfs_add_block_group(info, cache, 0);
10420 update_space_info(info, cache->flags, found_key.offset,
10421 btrfs_block_group_used(&cache->item),
10422 cache->bytes_super, &space_info);
10424 cache->space_info = space_info;
10426 link_block_group(cache);
10428 set_avail_alloc_bits(info, cache->flags);
10429 if (btrfs_chunk_readonly(info, cache->key.objectid)) {
10430 inc_block_group_ro(cache, 1);
10431 } else if (btrfs_block_group_used(&cache->item) == 0) {
10432 ASSERT(list_empty(&cache->bg_list));
10433 btrfs_mark_bg_unused(cache);
10437 list_for_each_entry_rcu(space_info, &info->space_info, list) {
10438 if (!(get_alloc_profile(info, space_info->flags) &
10439 (BTRFS_BLOCK_GROUP_RAID10 |
10440 BTRFS_BLOCK_GROUP_RAID1 |
10441 BTRFS_BLOCK_GROUP_RAID5 |
10442 BTRFS_BLOCK_GROUP_RAID6 |
10443 BTRFS_BLOCK_GROUP_DUP)))
10446 * avoid allocating from un-mirrored block group if there are
10447 * mirrored block groups.
10449 list_for_each_entry(cache,
10450 &space_info->block_groups[BTRFS_RAID_RAID0],
10452 inc_block_group_ro(cache, 1);
10453 list_for_each_entry(cache,
10454 &space_info->block_groups[BTRFS_RAID_SINGLE],
10456 inc_block_group_ro(cache, 1);
10459 btrfs_add_raid_kobjects(info);
10460 init_global_block_rsv(info);
10461 ret = check_chunk_block_group_mappings(info);
10463 btrfs_free_path(path);
10467 void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans)
10469 struct btrfs_fs_info *fs_info = trans->fs_info;
10470 struct btrfs_block_group_cache *block_group;
10471 struct btrfs_root *extent_root = fs_info->extent_root;
10472 struct btrfs_block_group_item item;
10473 struct btrfs_key key;
10476 if (!trans->can_flush_pending_bgs)
10479 while (!list_empty(&trans->new_bgs)) {
10480 block_group = list_first_entry(&trans->new_bgs,
10481 struct btrfs_block_group_cache,
10486 spin_lock(&block_group->lock);
10487 memcpy(&item, &block_group->item, sizeof(item));
10488 memcpy(&key, &block_group->key, sizeof(key));
10489 spin_unlock(&block_group->lock);
10491 ret = btrfs_insert_item(trans, extent_root, &key, &item,
10494 btrfs_abort_transaction(trans, ret);
10495 ret = btrfs_finish_chunk_alloc(trans, key.objectid, key.offset);
10497 btrfs_abort_transaction(trans, ret);
10498 add_block_group_free_space(trans, block_group);
10499 /* already aborted the transaction if it failed. */
10501 btrfs_delayed_refs_rsv_release(fs_info, 1);
10502 list_del_init(&block_group->bg_list);
10504 btrfs_trans_release_chunk_metadata(trans);
10507 int btrfs_make_block_group(struct btrfs_trans_handle *trans, u64 bytes_used,
10508 u64 type, u64 chunk_offset, u64 size)
10510 struct btrfs_fs_info *fs_info = trans->fs_info;
10511 struct btrfs_block_group_cache *cache;
10514 btrfs_set_log_full_commit(trans);
10516 cache = btrfs_create_block_group_cache(fs_info, chunk_offset, size);
10520 btrfs_set_block_group_used(&cache->item, bytes_used);
10521 btrfs_set_block_group_chunk_objectid(&cache->item,
10522 BTRFS_FIRST_CHUNK_TREE_OBJECTID);
10523 btrfs_set_block_group_flags(&cache->item, type);
10525 cache->flags = type;
10526 cache->last_byte_to_unpin = (u64)-1;
10527 cache->cached = BTRFS_CACHE_FINISHED;
10528 cache->needs_free_space = 1;
10529 ret = exclude_super_stripes(cache);
10532 * We may have excluded something, so call this just in
10535 free_excluded_extents(cache);
10536 btrfs_put_block_group(cache);
10540 add_new_free_space(cache, chunk_offset, chunk_offset + size);
10542 free_excluded_extents(cache);
10544 #ifdef CONFIG_BTRFS_DEBUG
10545 if (btrfs_should_fragment_free_space(cache)) {
10546 u64 new_bytes_used = size - bytes_used;
10548 bytes_used += new_bytes_used >> 1;
10549 fragment_free_space(cache);
10553 * Ensure the corresponding space_info object is created and
10554 * assigned to our block group. We want our bg to be added to the rbtree
10555 * with its ->space_info set.
10557 cache->space_info = __find_space_info(fs_info, cache->flags);
10558 ASSERT(cache->space_info);
10560 ret = btrfs_add_block_group_cache(fs_info, cache);
10562 btrfs_remove_free_space_cache(cache);
10563 btrfs_put_block_group(cache);
10568 * Now that our block group has its ->space_info set and is inserted in
10569 * the rbtree, update the space info's counters.
10571 trace_btrfs_add_block_group(fs_info, cache, 1);
10572 update_space_info(fs_info, cache->flags, size, bytes_used,
10573 cache->bytes_super, &cache->space_info);
10574 update_global_block_rsv(fs_info);
10576 link_block_group(cache);
10578 list_add_tail(&cache->bg_list, &trans->new_bgs);
10579 trans->delayed_ref_updates++;
10580 btrfs_update_delayed_refs_rsv(trans);
10582 set_avail_alloc_bits(fs_info, type);
10586 static void clear_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
10588 u64 extra_flags = chunk_to_extended(flags) &
10589 BTRFS_EXTENDED_PROFILE_MASK;
10591 write_seqlock(&fs_info->profiles_lock);
10592 if (flags & BTRFS_BLOCK_GROUP_DATA)
10593 fs_info->avail_data_alloc_bits &= ~extra_flags;
10594 if (flags & BTRFS_BLOCK_GROUP_METADATA)
10595 fs_info->avail_metadata_alloc_bits &= ~extra_flags;
10596 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
10597 fs_info->avail_system_alloc_bits &= ~extra_flags;
10598 write_sequnlock(&fs_info->profiles_lock);
10601 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
10602 u64 group_start, struct extent_map *em)
10604 struct btrfs_fs_info *fs_info = trans->fs_info;
10605 struct btrfs_root *root = fs_info->extent_root;
10606 struct btrfs_path *path;
10607 struct btrfs_block_group_cache *block_group;
10608 struct btrfs_free_cluster *cluster;
10609 struct btrfs_root *tree_root = fs_info->tree_root;
10610 struct btrfs_key key;
10611 struct inode *inode;
10612 struct kobject *kobj = NULL;
10616 struct btrfs_caching_control *caching_ctl = NULL;
10618 bool remove_rsv = false;
10620 block_group = btrfs_lookup_block_group(fs_info, group_start);
10621 BUG_ON(!block_group);
10622 BUG_ON(!block_group->ro);
10624 trace_btrfs_remove_block_group(block_group);
10626 * Free the reserved super bytes from this block group before
10629 free_excluded_extents(block_group);
10630 btrfs_free_ref_tree_range(fs_info, block_group->key.objectid,
10631 block_group->key.offset);
10633 memcpy(&key, &block_group->key, sizeof(key));
10634 index = btrfs_bg_flags_to_raid_index(block_group->flags);
10635 factor = btrfs_bg_type_to_factor(block_group->flags);
10637 /* make sure this block group isn't part of an allocation cluster */
10638 cluster = &fs_info->data_alloc_cluster;
10639 spin_lock(&cluster->refill_lock);
10640 btrfs_return_cluster_to_free_space(block_group, cluster);
10641 spin_unlock(&cluster->refill_lock);
10644 * make sure this block group isn't part of a metadata
10645 * allocation cluster
10647 cluster = &fs_info->meta_alloc_cluster;
10648 spin_lock(&cluster->refill_lock);
10649 btrfs_return_cluster_to_free_space(block_group, cluster);
10650 spin_unlock(&cluster->refill_lock);
10652 path = btrfs_alloc_path();
10659 * get the inode first so any iput calls done for the io_list
10660 * aren't the final iput (no unlinks allowed now)
10662 inode = lookup_free_space_inode(block_group, path);
10664 mutex_lock(&trans->transaction->cache_write_mutex);
10666 * Make sure our free space cache IO is done before removing the
10669 spin_lock(&trans->transaction->dirty_bgs_lock);
10670 if (!list_empty(&block_group->io_list)) {
10671 list_del_init(&block_group->io_list);
10673 WARN_ON(!IS_ERR(inode) && inode != block_group->io_ctl.inode);
10675 spin_unlock(&trans->transaction->dirty_bgs_lock);
10676 btrfs_wait_cache_io(trans, block_group, path);
10677 btrfs_put_block_group(block_group);
10678 spin_lock(&trans->transaction->dirty_bgs_lock);
10681 if (!list_empty(&block_group->dirty_list)) {
10682 list_del_init(&block_group->dirty_list);
10684 btrfs_put_block_group(block_group);
10686 spin_unlock(&trans->transaction->dirty_bgs_lock);
10687 mutex_unlock(&trans->transaction->cache_write_mutex);
10689 if (!IS_ERR(inode)) {
10690 ret = btrfs_orphan_add(trans, BTRFS_I(inode));
10692 btrfs_add_delayed_iput(inode);
10695 clear_nlink(inode);
10696 /* One for the block groups ref */
10697 spin_lock(&block_group->lock);
10698 if (block_group->iref) {
10699 block_group->iref = 0;
10700 block_group->inode = NULL;
10701 spin_unlock(&block_group->lock);
10704 spin_unlock(&block_group->lock);
10706 /* One for our lookup ref */
10707 btrfs_add_delayed_iput(inode);
10710 key.objectid = BTRFS_FREE_SPACE_OBJECTID;
10711 key.offset = block_group->key.objectid;
10714 ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1);
10718 btrfs_release_path(path);
10720 ret = btrfs_del_item(trans, tree_root, path);
10723 btrfs_release_path(path);
10726 spin_lock(&fs_info->block_group_cache_lock);
10727 rb_erase(&block_group->cache_node,
10728 &fs_info->block_group_cache_tree);
10729 RB_CLEAR_NODE(&block_group->cache_node);
10731 if (fs_info->first_logical_byte == block_group->key.objectid)
10732 fs_info->first_logical_byte = (u64)-1;
10733 spin_unlock(&fs_info->block_group_cache_lock);
10735 down_write(&block_group->space_info->groups_sem);
10737 * we must use list_del_init so people can check to see if they
10738 * are still on the list after taking the semaphore
10740 list_del_init(&block_group->list);
10741 if (list_empty(&block_group->space_info->block_groups[index])) {
10742 kobj = block_group->space_info->block_group_kobjs[index];
10743 block_group->space_info->block_group_kobjs[index] = NULL;
10744 clear_avail_alloc_bits(fs_info, block_group->flags);
10746 up_write(&block_group->space_info->groups_sem);
10752 if (block_group->has_caching_ctl)
10753 caching_ctl = get_caching_control(block_group);
10754 if (block_group->cached == BTRFS_CACHE_STARTED)
10755 wait_block_group_cache_done(block_group);
10756 if (block_group->has_caching_ctl) {
10757 down_write(&fs_info->commit_root_sem);
10758 if (!caching_ctl) {
10759 struct btrfs_caching_control *ctl;
10761 list_for_each_entry(ctl,
10762 &fs_info->caching_block_groups, list)
10763 if (ctl->block_group == block_group) {
10765 refcount_inc(&caching_ctl->count);
10770 list_del_init(&caching_ctl->list);
10771 up_write(&fs_info->commit_root_sem);
10773 /* Once for the caching bgs list and once for us. */
10774 put_caching_control(caching_ctl);
10775 put_caching_control(caching_ctl);
10779 spin_lock(&trans->transaction->dirty_bgs_lock);
10780 WARN_ON(!list_empty(&block_group->dirty_list));
10781 WARN_ON(!list_empty(&block_group->io_list));
10782 spin_unlock(&trans->transaction->dirty_bgs_lock);
10784 btrfs_remove_free_space_cache(block_group);
10786 spin_lock(&block_group->space_info->lock);
10787 list_del_init(&block_group->ro_list);
10789 if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
10790 WARN_ON(block_group->space_info->total_bytes
10791 < block_group->key.offset);
10792 WARN_ON(block_group->space_info->bytes_readonly
10793 < block_group->key.offset);
10794 WARN_ON(block_group->space_info->disk_total
10795 < block_group->key.offset * factor);
10797 block_group->space_info->total_bytes -= block_group->key.offset;
10798 block_group->space_info->bytes_readonly -= block_group->key.offset;
10799 block_group->space_info->disk_total -= block_group->key.offset * factor;
10801 spin_unlock(&block_group->space_info->lock);
10803 memcpy(&key, &block_group->key, sizeof(key));
10805 mutex_lock(&fs_info->chunk_mutex);
10806 spin_lock(&block_group->lock);
10807 block_group->removed = 1;
10809 * At this point trimming can't start on this block group, because we
10810 * removed the block group from the tree fs_info->block_group_cache_tree
10811 * so no one can't find it anymore and even if someone already got this
10812 * block group before we removed it from the rbtree, they have already
10813 * incremented block_group->trimming - if they didn't, they won't find
10814 * any free space entries because we already removed them all when we
10815 * called btrfs_remove_free_space_cache().
10817 * And we must not remove the extent map from the fs_info->mapping_tree
10818 * to prevent the same logical address range and physical device space
10819 * ranges from being reused for a new block group. This is because our
10820 * fs trim operation (btrfs_trim_fs() / btrfs_ioctl_fitrim()) is
10821 * completely transactionless, so while it is trimming a range the
10822 * currently running transaction might finish and a new one start,
10823 * allowing for new block groups to be created that can reuse the same
10824 * physical device locations unless we take this special care.
10826 * There may also be an implicit trim operation if the file system
10827 * is mounted with -odiscard. The same protections must remain
10828 * in place until the extents have been discarded completely when
10829 * the transaction commit has completed.
10831 remove_em = (atomic_read(&block_group->trimming) == 0);
10832 spin_unlock(&block_group->lock);
10835 struct extent_map_tree *em_tree;
10837 em_tree = &fs_info->mapping_tree.map_tree;
10838 write_lock(&em_tree->lock);
10839 remove_extent_mapping(em_tree, em);
10840 write_unlock(&em_tree->lock);
10841 /* once for the tree */
10842 free_extent_map(em);
10845 mutex_unlock(&fs_info->chunk_mutex);
10847 ret = remove_block_group_free_space(trans, block_group);
10851 btrfs_put_block_group(block_group);
10852 btrfs_put_block_group(block_group);
10854 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
10860 ret = btrfs_del_item(trans, root, path);
10863 btrfs_delayed_refs_rsv_release(fs_info, 1);
10864 btrfs_free_path(path);
10868 struct btrfs_trans_handle *
10869 btrfs_start_trans_remove_block_group(struct btrfs_fs_info *fs_info,
10870 const u64 chunk_offset)
10872 struct extent_map_tree *em_tree = &fs_info->mapping_tree.map_tree;
10873 struct extent_map *em;
10874 struct map_lookup *map;
10875 unsigned int num_items;
10877 read_lock(&em_tree->lock);
10878 em = lookup_extent_mapping(em_tree, chunk_offset, 1);
10879 read_unlock(&em_tree->lock);
10880 ASSERT(em && em->start == chunk_offset);
10883 * We need to reserve 3 + N units from the metadata space info in order
10884 * to remove a block group (done at btrfs_remove_chunk() and at
10885 * btrfs_remove_block_group()), which are used for:
10887 * 1 unit for adding the free space inode's orphan (located in the tree
10889 * 1 unit for deleting the block group item (located in the extent
10891 * 1 unit for deleting the free space item (located in tree of tree
10893 * N units for deleting N device extent items corresponding to each
10894 * stripe (located in the device tree).
10896 * In order to remove a block group we also need to reserve units in the
10897 * system space info in order to update the chunk tree (update one or
10898 * more device items and remove one chunk item), but this is done at
10899 * btrfs_remove_chunk() through a call to check_system_chunk().
10901 map = em->map_lookup;
10902 num_items = 3 + map->num_stripes;
10903 free_extent_map(em);
10905 return btrfs_start_transaction_fallback_global_rsv(fs_info->extent_root,
10910 * Process the unused_bgs list and remove any that don't have any allocated
10911 * space inside of them.
10913 void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info)
10915 struct btrfs_block_group_cache *block_group;
10916 struct btrfs_space_info *space_info;
10917 struct btrfs_trans_handle *trans;
10920 if (!test_bit(BTRFS_FS_OPEN, &fs_info->flags))
10923 spin_lock(&fs_info->unused_bgs_lock);
10924 while (!list_empty(&fs_info->unused_bgs)) {
10928 block_group = list_first_entry(&fs_info->unused_bgs,
10929 struct btrfs_block_group_cache,
10931 list_del_init(&block_group->bg_list);
10933 space_info = block_group->space_info;
10935 if (ret || btrfs_mixed_space_info(space_info)) {
10936 btrfs_put_block_group(block_group);
10939 spin_unlock(&fs_info->unused_bgs_lock);
10941 mutex_lock(&fs_info->delete_unused_bgs_mutex);
10943 /* Don't want to race with allocators so take the groups_sem */
10944 down_write(&space_info->groups_sem);
10945 spin_lock(&block_group->lock);
10946 if (block_group->reserved || block_group->pinned ||
10947 btrfs_block_group_used(&block_group->item) ||
10949 list_is_singular(&block_group->list)) {
10951 * We want to bail if we made new allocations or have
10952 * outstanding allocations in this block group. We do
10953 * the ro check in case balance is currently acting on
10954 * this block group.
10956 trace_btrfs_skip_unused_block_group(block_group);
10957 spin_unlock(&block_group->lock);
10958 up_write(&space_info->groups_sem);
10961 spin_unlock(&block_group->lock);
10963 /* We don't want to force the issue, only flip if it's ok. */
10964 ret = inc_block_group_ro(block_group, 0);
10965 up_write(&space_info->groups_sem);
10972 * Want to do this before we do anything else so we can recover
10973 * properly if we fail to join the transaction.
10975 trans = btrfs_start_trans_remove_block_group(fs_info,
10976 block_group->key.objectid);
10977 if (IS_ERR(trans)) {
10978 btrfs_dec_block_group_ro(block_group);
10979 ret = PTR_ERR(trans);
10984 * We could have pending pinned extents for this block group,
10985 * just delete them, we don't care about them anymore.
10987 start = block_group->key.objectid;
10988 end = start + block_group->key.offset - 1;
10990 * Hold the unused_bg_unpin_mutex lock to avoid racing with
10991 * btrfs_finish_extent_commit(). If we are at transaction N,
10992 * another task might be running finish_extent_commit() for the
10993 * previous transaction N - 1, and have seen a range belonging
10994 * to the block group in freed_extents[] before we were able to
10995 * clear the whole block group range from freed_extents[]. This
10996 * means that task can lookup for the block group after we
10997 * unpinned it from freed_extents[] and removed it, leading to
10998 * a BUG_ON() at btrfs_unpin_extent_range().
11000 mutex_lock(&fs_info->unused_bg_unpin_mutex);
11001 ret = clear_extent_bits(&fs_info->freed_extents[0], start, end,
11004 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
11005 btrfs_dec_block_group_ro(block_group);
11008 ret = clear_extent_bits(&fs_info->freed_extents[1], start, end,
11011 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
11012 btrfs_dec_block_group_ro(block_group);
11015 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
11017 /* Reset pinned so btrfs_put_block_group doesn't complain */
11018 spin_lock(&space_info->lock);
11019 spin_lock(&block_group->lock);
11021 update_bytes_pinned(space_info, -block_group->pinned);
11022 space_info->bytes_readonly += block_group->pinned;
11023 percpu_counter_add_batch(&space_info->total_bytes_pinned,
11024 -block_group->pinned,
11025 BTRFS_TOTAL_BYTES_PINNED_BATCH);
11026 block_group->pinned = 0;
11028 spin_unlock(&block_group->lock);
11029 spin_unlock(&space_info->lock);
11031 /* DISCARD can flip during remount */
11032 trimming = btrfs_test_opt(fs_info, DISCARD);
11034 /* Implicit trim during transaction commit. */
11036 btrfs_get_block_group_trimming(block_group);
11039 * Btrfs_remove_chunk will abort the transaction if things go
11042 ret = btrfs_remove_chunk(trans, block_group->key.objectid);
11046 btrfs_put_block_group_trimming(block_group);
11051 * If we're not mounted with -odiscard, we can just forget
11052 * about this block group. Otherwise we'll need to wait
11053 * until transaction commit to do the actual discard.
11056 spin_lock(&fs_info->unused_bgs_lock);
11058 * A concurrent scrub might have added us to the list
11059 * fs_info->unused_bgs, so use a list_move operation
11060 * to add the block group to the deleted_bgs list.
11062 list_move(&block_group->bg_list,
11063 &trans->transaction->deleted_bgs);
11064 spin_unlock(&fs_info->unused_bgs_lock);
11065 btrfs_get_block_group(block_group);
11068 btrfs_end_transaction(trans);
11070 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
11071 btrfs_put_block_group(block_group);
11072 spin_lock(&fs_info->unused_bgs_lock);
11074 spin_unlock(&fs_info->unused_bgs_lock);
11077 int btrfs_init_space_info(struct btrfs_fs_info *fs_info)
11079 struct btrfs_super_block *disk_super;
11085 disk_super = fs_info->super_copy;
11086 if (!btrfs_super_root(disk_super))
11089 features = btrfs_super_incompat_flags(disk_super);
11090 if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
11093 flags = BTRFS_BLOCK_GROUP_SYSTEM;
11094 ret = create_space_info(fs_info, flags);
11099 flags = BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA;
11100 ret = create_space_info(fs_info, flags);
11102 flags = BTRFS_BLOCK_GROUP_METADATA;
11103 ret = create_space_info(fs_info, flags);
11107 flags = BTRFS_BLOCK_GROUP_DATA;
11108 ret = create_space_info(fs_info, flags);
11114 int btrfs_error_unpin_extent_range(struct btrfs_fs_info *fs_info,
11115 u64 start, u64 end)
11117 return unpin_extent_range(fs_info, start, end, false);
11121 * It used to be that old block groups would be left around forever.
11122 * Iterating over them would be enough to trim unused space. Since we
11123 * now automatically remove them, we also need to iterate over unallocated
11126 * We don't want a transaction for this since the discard may take a
11127 * substantial amount of time. We don't require that a transaction be
11128 * running, but we do need to take a running transaction into account
11129 * to ensure that we're not discarding chunks that were released or
11130 * allocated in the current transaction.
11132 * Holding the chunks lock will prevent other threads from allocating
11133 * or releasing chunks, but it won't prevent a running transaction
11134 * from committing and releasing the memory that the pending chunks
11135 * list head uses. For that, we need to take a reference to the
11136 * transaction and hold the commit root sem. We only need to hold
11137 * it while performing the free space search since we have already
11138 * held back allocations.
11140 static int btrfs_trim_free_extents(struct btrfs_device *device, u64 *trimmed)
11142 u64 start = SZ_1M, len = 0, end = 0;
11147 /* Discard not supported = nothing to do. */
11148 if (!blk_queue_discard(bdev_get_queue(device->bdev)))
11151 /* Not writable = nothing to do. */
11152 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state))
11155 /* No free space = nothing to do. */
11156 if (device->total_bytes <= device->bytes_used)
11162 struct btrfs_fs_info *fs_info = device->fs_info;
11165 ret = mutex_lock_interruptible(&fs_info->chunk_mutex);
11169 find_first_clear_extent_bit(&device->alloc_state, start,
11171 CHUNK_TRIMMED | CHUNK_ALLOCATED);
11173 * If find_first_clear_extent_bit find a range that spans the
11174 * end of the device it will set end to -1, in this case it's up
11175 * to the caller to trim the value to the size of the device.
11177 end = min(end, device->total_bytes - 1);
11178 len = end - start + 1;
11180 /* We didn't find any extents */
11182 mutex_unlock(&fs_info->chunk_mutex);
11187 ret = btrfs_issue_discard(device->bdev, start, len,
11190 set_extent_bits(&device->alloc_state, start,
11193 mutex_unlock(&fs_info->chunk_mutex);
11201 if (fatal_signal_pending(current)) {
11202 ret = -ERESTARTSYS;
11213 * Trim the whole filesystem by:
11214 * 1) trimming the free space in each block group
11215 * 2) trimming the unallocated space on each device
11217 * This will also continue trimming even if a block group or device encounters
11218 * an error. The return value will be the last error, or 0 if nothing bad
11221 int btrfs_trim_fs(struct btrfs_fs_info *fs_info, struct fstrim_range *range)
11223 struct btrfs_block_group_cache *cache = NULL;
11224 struct btrfs_device *device;
11225 struct list_head *devices;
11231 u64 dev_failed = 0;
11236 cache = btrfs_lookup_first_block_group(fs_info, range->start);
11237 for (; cache; cache = next_block_group(cache)) {
11238 if (cache->key.objectid >= (range->start + range->len)) {
11239 btrfs_put_block_group(cache);
11243 start = max(range->start, cache->key.objectid);
11244 end = min(range->start + range->len,
11245 cache->key.objectid + cache->key.offset);
11247 if (end - start >= range->minlen) {
11248 if (!block_group_cache_done(cache)) {
11249 ret = cache_block_group(cache, 0);
11255 ret = wait_block_group_cache_done(cache);
11262 ret = btrfs_trim_block_group(cache,
11268 trimmed += group_trimmed;
11278 btrfs_warn(fs_info,
11279 "failed to trim %llu block group(s), last error %d",
11280 bg_failed, bg_ret);
11281 mutex_lock(&fs_info->fs_devices->device_list_mutex);
11282 devices = &fs_info->fs_devices->devices;
11283 list_for_each_entry(device, devices, dev_list) {
11284 ret = btrfs_trim_free_extents(device, &group_trimmed);
11291 trimmed += group_trimmed;
11293 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
11296 btrfs_warn(fs_info,
11297 "failed to trim %llu device(s), last error %d",
11298 dev_failed, dev_ret);
11299 range->len = trimmed;
11306 * btrfs_{start,end}_write_no_snapshotting() are similar to
11307 * mnt_{want,drop}_write(), they are used to prevent some tasks from writing
11308 * data into the page cache through nocow before the subvolume is snapshoted,
11309 * but flush the data into disk after the snapshot creation, or to prevent
11310 * operations while snapshotting is ongoing and that cause the snapshot to be
11311 * inconsistent (writes followed by expanding truncates for example).
11313 void btrfs_end_write_no_snapshotting(struct btrfs_root *root)
11315 percpu_counter_dec(&root->subv_writers->counter);
11316 cond_wake_up(&root->subv_writers->wait);
11319 int btrfs_start_write_no_snapshotting(struct btrfs_root *root)
11321 if (atomic_read(&root->will_be_snapshotted))
11324 percpu_counter_inc(&root->subv_writers->counter);
11326 * Make sure counter is updated before we check for snapshot creation.
11329 if (atomic_read(&root->will_be_snapshotted)) {
11330 btrfs_end_write_no_snapshotting(root);
11336 void btrfs_wait_for_snapshot_creation(struct btrfs_root *root)
11341 ret = btrfs_start_write_no_snapshotting(root);
11344 wait_var_event(&root->will_be_snapshotted,
11345 !atomic_read(&root->will_be_snapshotted));
11349 void btrfs_mark_bg_unused(struct btrfs_block_group_cache *bg)
11351 struct btrfs_fs_info *fs_info = bg->fs_info;
11353 spin_lock(&fs_info->unused_bgs_lock);
11354 if (list_empty(&bg->bg_list)) {
11355 btrfs_get_block_group(bg);
11356 trace_btrfs_add_unused_block_group(bg);
11357 list_add_tail(&bg->bg_list, &fs_info->unused_bgs);
11359 spin_unlock(&fs_info->unused_bgs_lock);