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,
54 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
55 struct btrfs_fs_info *fs_info,
56 struct btrfs_delayed_ref_node *node, u64 parent,
57 u64 root_objectid, u64 owner_objectid,
58 u64 owner_offset, int refs_to_drop,
59 struct btrfs_delayed_extent_op *extra_op);
60 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
61 struct extent_buffer *leaf,
62 struct btrfs_extent_item *ei);
63 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
64 struct btrfs_fs_info *fs_info,
65 u64 parent, u64 root_objectid,
66 u64 flags, u64 owner, u64 offset,
67 struct btrfs_key *ins, int ref_mod);
68 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
69 struct btrfs_fs_info *fs_info,
70 u64 parent, u64 root_objectid,
71 u64 flags, struct btrfs_disk_key *key,
72 int level, struct btrfs_key *ins);
73 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
74 struct btrfs_fs_info *fs_info, u64 flags,
76 static int find_next_key(struct btrfs_path *path, int level,
77 struct btrfs_key *key);
78 static void dump_space_info(struct btrfs_fs_info *fs_info,
79 struct btrfs_space_info *info, u64 bytes,
80 int dump_block_groups);
81 static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
83 static void space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
84 struct btrfs_space_info *space_info,
86 static void space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
87 struct btrfs_space_info *space_info,
91 block_group_cache_done(struct btrfs_block_group_cache *cache)
94 return cache->cached == BTRFS_CACHE_FINISHED ||
95 cache->cached == BTRFS_CACHE_ERROR;
98 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
100 return (cache->flags & bits) == bits;
103 void btrfs_get_block_group(struct btrfs_block_group_cache *cache)
105 atomic_inc(&cache->count);
108 void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
110 if (atomic_dec_and_test(&cache->count)) {
111 WARN_ON(cache->pinned > 0);
112 WARN_ON(cache->reserved > 0);
115 * If not empty, someone is still holding mutex of
116 * full_stripe_lock, which can only be released by caller.
117 * And it will definitely cause use-after-free when caller
118 * tries to release full stripe lock.
120 * No better way to resolve, but only to warn.
122 WARN_ON(!RB_EMPTY_ROOT(&cache->full_stripe_locks_root.root));
123 kfree(cache->free_space_ctl);
129 * this adds the block group to the fs_info rb tree for the block group
132 static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
133 struct btrfs_block_group_cache *block_group)
136 struct rb_node *parent = NULL;
137 struct btrfs_block_group_cache *cache;
139 spin_lock(&info->block_group_cache_lock);
140 p = &info->block_group_cache_tree.rb_node;
144 cache = rb_entry(parent, struct btrfs_block_group_cache,
146 if (block_group->key.objectid < cache->key.objectid) {
148 } else if (block_group->key.objectid > cache->key.objectid) {
151 spin_unlock(&info->block_group_cache_lock);
156 rb_link_node(&block_group->cache_node, parent, p);
157 rb_insert_color(&block_group->cache_node,
158 &info->block_group_cache_tree);
160 if (info->first_logical_byte > block_group->key.objectid)
161 info->first_logical_byte = block_group->key.objectid;
163 spin_unlock(&info->block_group_cache_lock);
169 * This will return the block group at or after bytenr if contains is 0, else
170 * it will return the block group that contains the bytenr
172 static struct btrfs_block_group_cache *
173 block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
176 struct btrfs_block_group_cache *cache, *ret = NULL;
180 spin_lock(&info->block_group_cache_lock);
181 n = info->block_group_cache_tree.rb_node;
184 cache = rb_entry(n, struct btrfs_block_group_cache,
186 end = cache->key.objectid + cache->key.offset - 1;
187 start = cache->key.objectid;
189 if (bytenr < start) {
190 if (!contains && (!ret || start < ret->key.objectid))
193 } else if (bytenr > start) {
194 if (contains && bytenr <= end) {
205 btrfs_get_block_group(ret);
206 if (bytenr == 0 && info->first_logical_byte > ret->key.objectid)
207 info->first_logical_byte = ret->key.objectid;
209 spin_unlock(&info->block_group_cache_lock);
214 static int add_excluded_extent(struct btrfs_fs_info *fs_info,
215 u64 start, u64 num_bytes)
217 u64 end = start + num_bytes - 1;
218 set_extent_bits(&fs_info->freed_extents[0],
219 start, end, EXTENT_UPTODATE);
220 set_extent_bits(&fs_info->freed_extents[1],
221 start, end, EXTENT_UPTODATE);
225 static void free_excluded_extents(struct btrfs_fs_info *fs_info,
226 struct btrfs_block_group_cache *cache)
230 start = cache->key.objectid;
231 end = start + cache->key.offset - 1;
233 clear_extent_bits(&fs_info->freed_extents[0],
234 start, end, EXTENT_UPTODATE);
235 clear_extent_bits(&fs_info->freed_extents[1],
236 start, end, EXTENT_UPTODATE);
239 static int exclude_super_stripes(struct btrfs_fs_info *fs_info,
240 struct btrfs_block_group_cache *cache)
247 if (cache->key.objectid < BTRFS_SUPER_INFO_OFFSET) {
248 stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->key.objectid;
249 cache->bytes_super += stripe_len;
250 ret = add_excluded_extent(fs_info, cache->key.objectid,
256 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
257 bytenr = btrfs_sb_offset(i);
258 ret = btrfs_rmap_block(fs_info, cache->key.objectid,
259 bytenr, 0, &logical, &nr, &stripe_len);
266 if (logical[nr] > cache->key.objectid +
270 if (logical[nr] + stripe_len <= cache->key.objectid)
274 if (start < cache->key.objectid) {
275 start = cache->key.objectid;
276 len = (logical[nr] + stripe_len) - start;
278 len = min_t(u64, stripe_len,
279 cache->key.objectid +
280 cache->key.offset - start);
283 cache->bytes_super += len;
284 ret = add_excluded_extent(fs_info, start, len);
296 static struct btrfs_caching_control *
297 get_caching_control(struct btrfs_block_group_cache *cache)
299 struct btrfs_caching_control *ctl;
301 spin_lock(&cache->lock);
302 if (!cache->caching_ctl) {
303 spin_unlock(&cache->lock);
307 ctl = cache->caching_ctl;
308 refcount_inc(&ctl->count);
309 spin_unlock(&cache->lock);
313 static void put_caching_control(struct btrfs_caching_control *ctl)
315 if (refcount_dec_and_test(&ctl->count))
319 #ifdef CONFIG_BTRFS_DEBUG
320 static void fragment_free_space(struct btrfs_block_group_cache *block_group)
322 struct btrfs_fs_info *fs_info = block_group->fs_info;
323 u64 start = block_group->key.objectid;
324 u64 len = block_group->key.offset;
325 u64 chunk = block_group->flags & BTRFS_BLOCK_GROUP_METADATA ?
326 fs_info->nodesize : fs_info->sectorsize;
327 u64 step = chunk << 1;
329 while (len > chunk) {
330 btrfs_remove_free_space(block_group, start, chunk);
341 * this is only called by cache_block_group, since we could have freed extents
342 * we need to check the pinned_extents for any extents that can't be used yet
343 * since their free space will be released as soon as the transaction commits.
345 u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
346 struct btrfs_fs_info *info, u64 start, u64 end)
348 u64 extent_start, extent_end, size, total_added = 0;
351 while (start < end) {
352 ret = find_first_extent_bit(info->pinned_extents, start,
353 &extent_start, &extent_end,
354 EXTENT_DIRTY | EXTENT_UPTODATE,
359 if (extent_start <= start) {
360 start = extent_end + 1;
361 } else if (extent_start > start && extent_start < end) {
362 size = extent_start - start;
364 ret = btrfs_add_free_space(block_group, start,
366 BUG_ON(ret); /* -ENOMEM or logic error */
367 start = extent_end + 1;
376 ret = btrfs_add_free_space(block_group, start, size);
377 BUG_ON(ret); /* -ENOMEM or logic error */
383 static int load_extent_tree_free(struct btrfs_caching_control *caching_ctl)
385 struct btrfs_block_group_cache *block_group = caching_ctl->block_group;
386 struct btrfs_fs_info *fs_info = block_group->fs_info;
387 struct btrfs_root *extent_root = fs_info->extent_root;
388 struct btrfs_path *path;
389 struct extent_buffer *leaf;
390 struct btrfs_key key;
397 path = btrfs_alloc_path();
401 last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
403 #ifdef CONFIG_BTRFS_DEBUG
405 * If we're fragmenting we don't want to make anybody think we can
406 * allocate from this block group until we've had a chance to fragment
409 if (btrfs_should_fragment_free_space(block_group))
413 * We don't want to deadlock with somebody trying to allocate a new
414 * extent for the extent root while also trying to search the extent
415 * root to add free space. So we skip locking and search the commit
416 * root, since its read-only
418 path->skip_locking = 1;
419 path->search_commit_root = 1;
420 path->reada = READA_FORWARD;
424 key.type = BTRFS_EXTENT_ITEM_KEY;
427 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
431 leaf = path->nodes[0];
432 nritems = btrfs_header_nritems(leaf);
435 if (btrfs_fs_closing(fs_info) > 1) {
440 if (path->slots[0] < nritems) {
441 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
443 ret = find_next_key(path, 0, &key);
447 if (need_resched() ||
448 rwsem_is_contended(&fs_info->commit_root_sem)) {
450 caching_ctl->progress = last;
451 btrfs_release_path(path);
452 up_read(&fs_info->commit_root_sem);
453 mutex_unlock(&caching_ctl->mutex);
455 mutex_lock(&caching_ctl->mutex);
456 down_read(&fs_info->commit_root_sem);
460 ret = btrfs_next_leaf(extent_root, path);
465 leaf = path->nodes[0];
466 nritems = btrfs_header_nritems(leaf);
470 if (key.objectid < last) {
473 key.type = BTRFS_EXTENT_ITEM_KEY;
476 caching_ctl->progress = last;
477 btrfs_release_path(path);
481 if (key.objectid < block_group->key.objectid) {
486 if (key.objectid >= block_group->key.objectid +
487 block_group->key.offset)
490 if (key.type == BTRFS_EXTENT_ITEM_KEY ||
491 key.type == BTRFS_METADATA_ITEM_KEY) {
492 total_found += add_new_free_space(block_group,
495 if (key.type == BTRFS_METADATA_ITEM_KEY)
496 last = key.objectid +
499 last = key.objectid + key.offset;
501 if (total_found > CACHING_CTL_WAKE_UP) {
504 wake_up(&caching_ctl->wait);
511 total_found += add_new_free_space(block_group, fs_info, last,
512 block_group->key.objectid +
513 block_group->key.offset);
514 caching_ctl->progress = (u64)-1;
517 btrfs_free_path(path);
521 static noinline void caching_thread(struct btrfs_work *work)
523 struct btrfs_block_group_cache *block_group;
524 struct btrfs_fs_info *fs_info;
525 struct btrfs_caching_control *caching_ctl;
528 caching_ctl = container_of(work, struct btrfs_caching_control, work);
529 block_group = caching_ctl->block_group;
530 fs_info = block_group->fs_info;
532 mutex_lock(&caching_ctl->mutex);
533 down_read(&fs_info->commit_root_sem);
535 if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE))
536 ret = load_free_space_tree(caching_ctl);
538 ret = load_extent_tree_free(caching_ctl);
540 spin_lock(&block_group->lock);
541 block_group->caching_ctl = NULL;
542 block_group->cached = ret ? BTRFS_CACHE_ERROR : BTRFS_CACHE_FINISHED;
543 spin_unlock(&block_group->lock);
545 #ifdef CONFIG_BTRFS_DEBUG
546 if (btrfs_should_fragment_free_space(block_group)) {
549 spin_lock(&block_group->space_info->lock);
550 spin_lock(&block_group->lock);
551 bytes_used = block_group->key.offset -
552 btrfs_block_group_used(&block_group->item);
553 block_group->space_info->bytes_used += bytes_used >> 1;
554 spin_unlock(&block_group->lock);
555 spin_unlock(&block_group->space_info->lock);
556 fragment_free_space(block_group);
560 caching_ctl->progress = (u64)-1;
562 up_read(&fs_info->commit_root_sem);
563 free_excluded_extents(fs_info, block_group);
564 mutex_unlock(&caching_ctl->mutex);
566 wake_up(&caching_ctl->wait);
568 put_caching_control(caching_ctl);
569 btrfs_put_block_group(block_group);
572 static int cache_block_group(struct btrfs_block_group_cache *cache,
576 struct btrfs_fs_info *fs_info = cache->fs_info;
577 struct btrfs_caching_control *caching_ctl;
580 caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_NOFS);
584 INIT_LIST_HEAD(&caching_ctl->list);
585 mutex_init(&caching_ctl->mutex);
586 init_waitqueue_head(&caching_ctl->wait);
587 caching_ctl->block_group = cache;
588 caching_ctl->progress = cache->key.objectid;
589 refcount_set(&caching_ctl->count, 1);
590 btrfs_init_work(&caching_ctl->work, btrfs_cache_helper,
591 caching_thread, NULL, NULL);
593 spin_lock(&cache->lock);
595 * This should be a rare occasion, but this could happen I think in the
596 * case where one thread starts to load the space cache info, and then
597 * some other thread starts a transaction commit which tries to do an
598 * allocation while the other thread is still loading the space cache
599 * info. The previous loop should have kept us from choosing this block
600 * group, but if we've moved to the state where we will wait on caching
601 * block groups we need to first check if we're doing a fast load here,
602 * so we can wait for it to finish, otherwise we could end up allocating
603 * from a block group who's cache gets evicted for one reason or
606 while (cache->cached == BTRFS_CACHE_FAST) {
607 struct btrfs_caching_control *ctl;
609 ctl = cache->caching_ctl;
610 refcount_inc(&ctl->count);
611 prepare_to_wait(&ctl->wait, &wait, TASK_UNINTERRUPTIBLE);
612 spin_unlock(&cache->lock);
616 finish_wait(&ctl->wait, &wait);
617 put_caching_control(ctl);
618 spin_lock(&cache->lock);
621 if (cache->cached != BTRFS_CACHE_NO) {
622 spin_unlock(&cache->lock);
626 WARN_ON(cache->caching_ctl);
627 cache->caching_ctl = caching_ctl;
628 cache->cached = BTRFS_CACHE_FAST;
629 spin_unlock(&cache->lock);
631 if (btrfs_test_opt(fs_info, SPACE_CACHE)) {
632 mutex_lock(&caching_ctl->mutex);
633 ret = load_free_space_cache(fs_info, cache);
635 spin_lock(&cache->lock);
637 cache->caching_ctl = NULL;
638 cache->cached = BTRFS_CACHE_FINISHED;
639 cache->last_byte_to_unpin = (u64)-1;
640 caching_ctl->progress = (u64)-1;
642 if (load_cache_only) {
643 cache->caching_ctl = NULL;
644 cache->cached = BTRFS_CACHE_NO;
646 cache->cached = BTRFS_CACHE_STARTED;
647 cache->has_caching_ctl = 1;
650 spin_unlock(&cache->lock);
651 #ifdef CONFIG_BTRFS_DEBUG
653 btrfs_should_fragment_free_space(cache)) {
656 spin_lock(&cache->space_info->lock);
657 spin_lock(&cache->lock);
658 bytes_used = cache->key.offset -
659 btrfs_block_group_used(&cache->item);
660 cache->space_info->bytes_used += bytes_used >> 1;
661 spin_unlock(&cache->lock);
662 spin_unlock(&cache->space_info->lock);
663 fragment_free_space(cache);
666 mutex_unlock(&caching_ctl->mutex);
668 wake_up(&caching_ctl->wait);
670 put_caching_control(caching_ctl);
671 free_excluded_extents(fs_info, cache);
676 * We're either using the free space tree or no caching at all.
677 * Set cached to the appropriate value and wakeup any waiters.
679 spin_lock(&cache->lock);
680 if (load_cache_only) {
681 cache->caching_ctl = NULL;
682 cache->cached = BTRFS_CACHE_NO;
684 cache->cached = BTRFS_CACHE_STARTED;
685 cache->has_caching_ctl = 1;
687 spin_unlock(&cache->lock);
688 wake_up(&caching_ctl->wait);
691 if (load_cache_only) {
692 put_caching_control(caching_ctl);
696 down_write(&fs_info->commit_root_sem);
697 refcount_inc(&caching_ctl->count);
698 list_add_tail(&caching_ctl->list, &fs_info->caching_block_groups);
699 up_write(&fs_info->commit_root_sem);
701 btrfs_get_block_group(cache);
703 btrfs_queue_work(fs_info->caching_workers, &caching_ctl->work);
709 * return the block group that starts at or after bytenr
711 static struct btrfs_block_group_cache *
712 btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr)
714 return block_group_cache_tree_search(info, bytenr, 0);
718 * return the block group that contains the given bytenr
720 struct btrfs_block_group_cache *btrfs_lookup_block_group(
721 struct btrfs_fs_info *info,
724 return block_group_cache_tree_search(info, bytenr, 1);
727 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
730 struct list_head *head = &info->space_info;
731 struct btrfs_space_info *found;
733 flags &= BTRFS_BLOCK_GROUP_TYPE_MASK;
736 list_for_each_entry_rcu(found, head, list) {
737 if (found->flags & flags) {
746 static void add_pinned_bytes(struct btrfs_fs_info *fs_info, s64 num_bytes,
747 u64 owner, u64 root_objectid)
749 struct btrfs_space_info *space_info;
752 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
753 if (root_objectid == BTRFS_CHUNK_TREE_OBJECTID)
754 flags = BTRFS_BLOCK_GROUP_SYSTEM;
756 flags = BTRFS_BLOCK_GROUP_METADATA;
758 flags = BTRFS_BLOCK_GROUP_DATA;
761 space_info = __find_space_info(fs_info, flags);
763 percpu_counter_add(&space_info->total_bytes_pinned, num_bytes);
767 * after adding space to the filesystem, we need to clear the full flags
768 * on all the space infos.
770 void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
772 struct list_head *head = &info->space_info;
773 struct btrfs_space_info *found;
776 list_for_each_entry_rcu(found, head, list)
781 /* simple helper to search for an existing data extent at a given offset */
782 int btrfs_lookup_data_extent(struct btrfs_fs_info *fs_info, u64 start, u64 len)
785 struct btrfs_key key;
786 struct btrfs_path *path;
788 path = btrfs_alloc_path();
792 key.objectid = start;
794 key.type = BTRFS_EXTENT_ITEM_KEY;
795 ret = btrfs_search_slot(NULL, fs_info->extent_root, &key, path, 0, 0);
796 btrfs_free_path(path);
801 * helper function to lookup reference count and flags of a tree block.
803 * the head node for delayed ref is used to store the sum of all the
804 * reference count modifications queued up in the rbtree. the head
805 * node may also store the extent flags to set. This way you can check
806 * to see what the reference count and extent flags would be if all of
807 * the delayed refs are not processed.
809 int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
810 struct btrfs_fs_info *fs_info, u64 bytenr,
811 u64 offset, int metadata, u64 *refs, u64 *flags)
813 struct btrfs_delayed_ref_head *head;
814 struct btrfs_delayed_ref_root *delayed_refs;
815 struct btrfs_path *path;
816 struct btrfs_extent_item *ei;
817 struct extent_buffer *leaf;
818 struct btrfs_key key;
825 * If we don't have skinny metadata, don't bother doing anything
828 if (metadata && !btrfs_fs_incompat(fs_info, SKINNY_METADATA)) {
829 offset = fs_info->nodesize;
833 path = btrfs_alloc_path();
838 path->skip_locking = 1;
839 path->search_commit_root = 1;
843 key.objectid = bytenr;
846 key.type = BTRFS_METADATA_ITEM_KEY;
848 key.type = BTRFS_EXTENT_ITEM_KEY;
850 ret = btrfs_search_slot(trans, fs_info->extent_root, &key, path, 0, 0);
854 if (ret > 0 && metadata && key.type == BTRFS_METADATA_ITEM_KEY) {
855 if (path->slots[0]) {
857 btrfs_item_key_to_cpu(path->nodes[0], &key,
859 if (key.objectid == bytenr &&
860 key.type == BTRFS_EXTENT_ITEM_KEY &&
861 key.offset == fs_info->nodesize)
867 leaf = path->nodes[0];
868 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
869 if (item_size >= sizeof(*ei)) {
870 ei = btrfs_item_ptr(leaf, path->slots[0],
871 struct btrfs_extent_item);
872 num_refs = btrfs_extent_refs(leaf, ei);
873 extent_flags = btrfs_extent_flags(leaf, ei);
875 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
876 struct btrfs_extent_item_v0 *ei0;
877 BUG_ON(item_size != sizeof(*ei0));
878 ei0 = btrfs_item_ptr(leaf, path->slots[0],
879 struct btrfs_extent_item_v0);
880 num_refs = btrfs_extent_refs_v0(leaf, ei0);
881 /* FIXME: this isn't correct for data */
882 extent_flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
887 BUG_ON(num_refs == 0);
897 delayed_refs = &trans->transaction->delayed_refs;
898 spin_lock(&delayed_refs->lock);
899 head = btrfs_find_delayed_ref_head(delayed_refs, bytenr);
901 if (!mutex_trylock(&head->mutex)) {
902 refcount_inc(&head->refs);
903 spin_unlock(&delayed_refs->lock);
905 btrfs_release_path(path);
908 * Mutex was contended, block until it's released and try
911 mutex_lock(&head->mutex);
912 mutex_unlock(&head->mutex);
913 btrfs_put_delayed_ref_head(head);
916 spin_lock(&head->lock);
917 if (head->extent_op && head->extent_op->update_flags)
918 extent_flags |= head->extent_op->flags_to_set;
920 BUG_ON(num_refs == 0);
922 num_refs += head->ref_mod;
923 spin_unlock(&head->lock);
924 mutex_unlock(&head->mutex);
926 spin_unlock(&delayed_refs->lock);
928 WARN_ON(num_refs == 0);
932 *flags = extent_flags;
934 btrfs_free_path(path);
939 * Back reference rules. Back refs have three main goals:
941 * 1) differentiate between all holders of references to an extent so that
942 * when a reference is dropped we can make sure it was a valid reference
943 * before freeing the extent.
945 * 2) Provide enough information to quickly find the holders of an extent
946 * if we notice a given block is corrupted or bad.
948 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
949 * maintenance. This is actually the same as #2, but with a slightly
950 * different use case.
952 * There are two kinds of back refs. The implicit back refs is optimized
953 * for pointers in non-shared tree blocks. For a given pointer in a block,
954 * back refs of this kind provide information about the block's owner tree
955 * and the pointer's key. These information allow us to find the block by
956 * b-tree searching. The full back refs is for pointers in tree blocks not
957 * referenced by their owner trees. The location of tree block is recorded
958 * in the back refs. Actually the full back refs is generic, and can be
959 * used in all cases the implicit back refs is used. The major shortcoming
960 * of the full back refs is its overhead. Every time a tree block gets
961 * COWed, we have to update back refs entry for all pointers in it.
963 * For a newly allocated tree block, we use implicit back refs for
964 * pointers in it. This means most tree related operations only involve
965 * implicit back refs. For a tree block created in old transaction, the
966 * only way to drop a reference to it is COW it. So we can detect the
967 * event that tree block loses its owner tree's reference and do the
968 * back refs conversion.
970 * When a tree block is COWed through a tree, there are four cases:
972 * The reference count of the block is one and the tree is the block's
973 * owner tree. Nothing to do in this case.
975 * The reference count of the block is one and the tree is not the
976 * block's owner tree. In this case, full back refs is used for pointers
977 * in the block. Remove these full back refs, add implicit back refs for
978 * every pointers in the new block.
980 * The reference count of the block is greater than one and the tree is
981 * the block's owner tree. In this case, implicit back refs is used for
982 * pointers in the block. Add full back refs for every pointers in the
983 * block, increase lower level extents' reference counts. The original
984 * implicit back refs are entailed to the new block.
986 * The reference count of the block is greater than one and the tree is
987 * not the block's owner tree. Add implicit back refs for every pointer in
988 * the new block, increase lower level extents' reference count.
990 * Back Reference Key composing:
992 * The key objectid corresponds to the first byte in the extent,
993 * The key type is used to differentiate between types of back refs.
994 * There are different meanings of the key offset for different types
997 * File extents can be referenced by:
999 * - multiple snapshots, subvolumes, or different generations in one subvol
1000 * - different files inside a single subvolume
1001 * - different offsets inside a file (bookend extents in file.c)
1003 * The extent ref structure for the implicit back refs has fields for:
1005 * - Objectid of the subvolume root
1006 * - objectid of the file holding the reference
1007 * - original offset in the file
1008 * - how many bookend extents
1010 * The key offset for the implicit back refs is hash of the first
1013 * The extent ref structure for the full back refs has field for:
1015 * - number of pointers in the tree leaf
1017 * The key offset for the implicit back refs is the first byte of
1020 * When a file extent is allocated, The implicit back refs is used.
1021 * the fields are filled in:
1023 * (root_key.objectid, inode objectid, offset in file, 1)
1025 * When a file extent is removed file truncation, we find the
1026 * corresponding implicit back refs and check the following fields:
1028 * (btrfs_header_owner(leaf), inode objectid, offset in file)
1030 * Btree extents can be referenced by:
1032 * - Different subvolumes
1034 * Both the implicit back refs and the full back refs for tree blocks
1035 * only consist of key. The key offset for the implicit back refs is
1036 * objectid of block's owner tree. The key offset for the full back refs
1037 * is the first byte of parent block.
1039 * When implicit back refs is used, information about the lowest key and
1040 * level of the tree block are required. These information are stored in
1041 * tree block info structure.
1044 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1045 static int convert_extent_item_v0(struct btrfs_trans_handle *trans,
1046 struct btrfs_fs_info *fs_info,
1047 struct btrfs_path *path,
1048 u64 owner, u32 extra_size)
1050 struct btrfs_root *root = fs_info->extent_root;
1051 struct btrfs_extent_item *item;
1052 struct btrfs_extent_item_v0 *ei0;
1053 struct btrfs_extent_ref_v0 *ref0;
1054 struct btrfs_tree_block_info *bi;
1055 struct extent_buffer *leaf;
1056 struct btrfs_key key;
1057 struct btrfs_key found_key;
1058 u32 new_size = sizeof(*item);
1062 leaf = path->nodes[0];
1063 BUG_ON(btrfs_item_size_nr(leaf, path->slots[0]) != sizeof(*ei0));
1065 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1066 ei0 = btrfs_item_ptr(leaf, path->slots[0],
1067 struct btrfs_extent_item_v0);
1068 refs = btrfs_extent_refs_v0(leaf, ei0);
1070 if (owner == (u64)-1) {
1072 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1073 ret = btrfs_next_leaf(root, path);
1076 BUG_ON(ret > 0); /* Corruption */
1077 leaf = path->nodes[0];
1079 btrfs_item_key_to_cpu(leaf, &found_key,
1081 BUG_ON(key.objectid != found_key.objectid);
1082 if (found_key.type != BTRFS_EXTENT_REF_V0_KEY) {
1086 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1087 struct btrfs_extent_ref_v0);
1088 owner = btrfs_ref_objectid_v0(leaf, ref0);
1092 btrfs_release_path(path);
1094 if (owner < BTRFS_FIRST_FREE_OBJECTID)
1095 new_size += sizeof(*bi);
1097 new_size -= sizeof(*ei0);
1098 ret = btrfs_search_slot(trans, root, &key, path,
1099 new_size + extra_size, 1);
1102 BUG_ON(ret); /* Corruption */
1104 btrfs_extend_item(fs_info, path, new_size);
1106 leaf = path->nodes[0];
1107 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1108 btrfs_set_extent_refs(leaf, item, refs);
1109 /* FIXME: get real generation */
1110 btrfs_set_extent_generation(leaf, item, 0);
1111 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1112 btrfs_set_extent_flags(leaf, item,
1113 BTRFS_EXTENT_FLAG_TREE_BLOCK |
1114 BTRFS_BLOCK_FLAG_FULL_BACKREF);
1115 bi = (struct btrfs_tree_block_info *)(item + 1);
1116 /* FIXME: get first key of the block */
1117 memzero_extent_buffer(leaf, (unsigned long)bi, sizeof(*bi));
1118 btrfs_set_tree_block_level(leaf, bi, (int)owner);
1120 btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_DATA);
1122 btrfs_mark_buffer_dirty(leaf);
1128 * is_data == BTRFS_REF_TYPE_BLOCK, tree block type is required,
1129 * is_data == BTRFS_REF_TYPE_DATA, data type is requried,
1130 * is_data == BTRFS_REF_TYPE_ANY, either type is OK.
1132 int btrfs_get_extent_inline_ref_type(const struct extent_buffer *eb,
1133 struct btrfs_extent_inline_ref *iref,
1134 enum btrfs_inline_ref_type is_data)
1136 int type = btrfs_extent_inline_ref_type(eb, iref);
1137 u64 offset = btrfs_extent_inline_ref_offset(eb, iref);
1139 if (type == BTRFS_TREE_BLOCK_REF_KEY ||
1140 type == BTRFS_SHARED_BLOCK_REF_KEY ||
1141 type == BTRFS_SHARED_DATA_REF_KEY ||
1142 type == BTRFS_EXTENT_DATA_REF_KEY) {
1143 if (is_data == BTRFS_REF_TYPE_BLOCK) {
1144 if (type == BTRFS_TREE_BLOCK_REF_KEY)
1146 if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1147 ASSERT(eb->fs_info);
1149 * Every shared one has parent tree
1150 * block, which must be aligned to
1154 IS_ALIGNED(offset, eb->fs_info->nodesize))
1157 } else if (is_data == BTRFS_REF_TYPE_DATA) {
1158 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1160 if (type == BTRFS_SHARED_DATA_REF_KEY) {
1161 ASSERT(eb->fs_info);
1163 * Every shared one has parent tree
1164 * block, which must be aligned to
1168 IS_ALIGNED(offset, eb->fs_info->nodesize))
1172 ASSERT(is_data == BTRFS_REF_TYPE_ANY);
1177 btrfs_print_leaf((struct extent_buffer *)eb);
1178 btrfs_err(eb->fs_info, "eb %llu invalid extent inline ref type %d",
1182 return BTRFS_REF_TYPE_INVALID;
1185 static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
1187 u32 high_crc = ~(u32)0;
1188 u32 low_crc = ~(u32)0;
1191 lenum = cpu_to_le64(root_objectid);
1192 high_crc = crc32c(high_crc, &lenum, sizeof(lenum));
1193 lenum = cpu_to_le64(owner);
1194 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
1195 lenum = cpu_to_le64(offset);
1196 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
1198 return ((u64)high_crc << 31) ^ (u64)low_crc;
1201 static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
1202 struct btrfs_extent_data_ref *ref)
1204 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
1205 btrfs_extent_data_ref_objectid(leaf, ref),
1206 btrfs_extent_data_ref_offset(leaf, ref));
1209 static int match_extent_data_ref(struct extent_buffer *leaf,
1210 struct btrfs_extent_data_ref *ref,
1211 u64 root_objectid, u64 owner, u64 offset)
1213 if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
1214 btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
1215 btrfs_extent_data_ref_offset(leaf, ref) != offset)
1220 static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
1221 struct btrfs_fs_info *fs_info,
1222 struct btrfs_path *path,
1223 u64 bytenr, u64 parent,
1225 u64 owner, u64 offset)
1227 struct btrfs_root *root = fs_info->extent_root;
1228 struct btrfs_key key;
1229 struct btrfs_extent_data_ref *ref;
1230 struct extent_buffer *leaf;
1236 key.objectid = bytenr;
1238 key.type = BTRFS_SHARED_DATA_REF_KEY;
1239 key.offset = parent;
1241 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1242 key.offset = hash_extent_data_ref(root_objectid,
1247 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1256 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1257 key.type = BTRFS_EXTENT_REF_V0_KEY;
1258 btrfs_release_path(path);
1259 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1270 leaf = path->nodes[0];
1271 nritems = btrfs_header_nritems(leaf);
1273 if (path->slots[0] >= nritems) {
1274 ret = btrfs_next_leaf(root, path);
1280 leaf = path->nodes[0];
1281 nritems = btrfs_header_nritems(leaf);
1285 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1286 if (key.objectid != bytenr ||
1287 key.type != BTRFS_EXTENT_DATA_REF_KEY)
1290 ref = btrfs_item_ptr(leaf, path->slots[0],
1291 struct btrfs_extent_data_ref);
1293 if (match_extent_data_ref(leaf, ref, root_objectid,
1296 btrfs_release_path(path);
1308 static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
1309 struct btrfs_fs_info *fs_info,
1310 struct btrfs_path *path,
1311 u64 bytenr, u64 parent,
1312 u64 root_objectid, u64 owner,
1313 u64 offset, int refs_to_add)
1315 struct btrfs_root *root = fs_info->extent_root;
1316 struct btrfs_key key;
1317 struct extent_buffer *leaf;
1322 key.objectid = bytenr;
1324 key.type = BTRFS_SHARED_DATA_REF_KEY;
1325 key.offset = parent;
1326 size = sizeof(struct btrfs_shared_data_ref);
1328 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1329 key.offset = hash_extent_data_ref(root_objectid,
1331 size = sizeof(struct btrfs_extent_data_ref);
1334 ret = btrfs_insert_empty_item(trans, root, path, &key, size);
1335 if (ret && ret != -EEXIST)
1338 leaf = path->nodes[0];
1340 struct btrfs_shared_data_ref *ref;
1341 ref = btrfs_item_ptr(leaf, path->slots[0],
1342 struct btrfs_shared_data_ref);
1344 btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
1346 num_refs = btrfs_shared_data_ref_count(leaf, ref);
1347 num_refs += refs_to_add;
1348 btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
1351 struct btrfs_extent_data_ref *ref;
1352 while (ret == -EEXIST) {
1353 ref = btrfs_item_ptr(leaf, path->slots[0],
1354 struct btrfs_extent_data_ref);
1355 if (match_extent_data_ref(leaf, ref, root_objectid,
1358 btrfs_release_path(path);
1360 ret = btrfs_insert_empty_item(trans, root, path, &key,
1362 if (ret && ret != -EEXIST)
1365 leaf = path->nodes[0];
1367 ref = btrfs_item_ptr(leaf, path->slots[0],
1368 struct btrfs_extent_data_ref);
1370 btrfs_set_extent_data_ref_root(leaf, ref,
1372 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
1373 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
1374 btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
1376 num_refs = btrfs_extent_data_ref_count(leaf, ref);
1377 num_refs += refs_to_add;
1378 btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
1381 btrfs_mark_buffer_dirty(leaf);
1384 btrfs_release_path(path);
1388 static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
1389 struct btrfs_fs_info *fs_info,
1390 struct btrfs_path *path,
1391 int refs_to_drop, int *last_ref)
1393 struct btrfs_key key;
1394 struct btrfs_extent_data_ref *ref1 = NULL;
1395 struct btrfs_shared_data_ref *ref2 = NULL;
1396 struct extent_buffer *leaf;
1400 leaf = path->nodes[0];
1401 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1403 if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1404 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1405 struct btrfs_extent_data_ref);
1406 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1407 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1408 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1409 struct btrfs_shared_data_ref);
1410 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1411 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1412 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1413 struct btrfs_extent_ref_v0 *ref0;
1414 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1415 struct btrfs_extent_ref_v0);
1416 num_refs = btrfs_ref_count_v0(leaf, ref0);
1422 BUG_ON(num_refs < refs_to_drop);
1423 num_refs -= refs_to_drop;
1425 if (num_refs == 0) {
1426 ret = btrfs_del_item(trans, fs_info->extent_root, path);
1429 if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
1430 btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
1431 else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
1432 btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
1433 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1435 struct btrfs_extent_ref_v0 *ref0;
1436 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1437 struct btrfs_extent_ref_v0);
1438 btrfs_set_ref_count_v0(leaf, ref0, num_refs);
1441 btrfs_mark_buffer_dirty(leaf);
1446 static noinline u32 extent_data_ref_count(struct btrfs_path *path,
1447 struct btrfs_extent_inline_ref *iref)
1449 struct btrfs_key key;
1450 struct extent_buffer *leaf;
1451 struct btrfs_extent_data_ref *ref1;
1452 struct btrfs_shared_data_ref *ref2;
1456 leaf = path->nodes[0];
1457 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1460 * If type is invalid, we should have bailed out earlier than
1463 type = btrfs_get_extent_inline_ref_type(leaf, iref, BTRFS_REF_TYPE_DATA);
1464 ASSERT(type != BTRFS_REF_TYPE_INVALID);
1465 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1466 ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
1467 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1469 ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
1470 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1472 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1473 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1474 struct btrfs_extent_data_ref);
1475 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1476 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1477 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1478 struct btrfs_shared_data_ref);
1479 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1480 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1481 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1482 struct btrfs_extent_ref_v0 *ref0;
1483 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1484 struct btrfs_extent_ref_v0);
1485 num_refs = btrfs_ref_count_v0(leaf, ref0);
1493 static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
1494 struct btrfs_fs_info *fs_info,
1495 struct btrfs_path *path,
1496 u64 bytenr, u64 parent,
1499 struct btrfs_root *root = fs_info->extent_root;
1500 struct btrfs_key key;
1503 key.objectid = bytenr;
1505 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1506 key.offset = parent;
1508 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1509 key.offset = root_objectid;
1512 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1515 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1516 if (ret == -ENOENT && parent) {
1517 btrfs_release_path(path);
1518 key.type = BTRFS_EXTENT_REF_V0_KEY;
1519 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1527 static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
1528 struct btrfs_fs_info *fs_info,
1529 struct btrfs_path *path,
1530 u64 bytenr, u64 parent,
1533 struct btrfs_key key;
1536 key.objectid = bytenr;
1538 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1539 key.offset = parent;
1541 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1542 key.offset = root_objectid;
1545 ret = btrfs_insert_empty_item(trans, fs_info->extent_root,
1547 btrfs_release_path(path);
1551 static inline int extent_ref_type(u64 parent, u64 owner)
1554 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1556 type = BTRFS_SHARED_BLOCK_REF_KEY;
1558 type = BTRFS_TREE_BLOCK_REF_KEY;
1561 type = BTRFS_SHARED_DATA_REF_KEY;
1563 type = BTRFS_EXTENT_DATA_REF_KEY;
1568 static int find_next_key(struct btrfs_path *path, int level,
1569 struct btrfs_key *key)
1572 for (; level < BTRFS_MAX_LEVEL; level++) {
1573 if (!path->nodes[level])
1575 if (path->slots[level] + 1 >=
1576 btrfs_header_nritems(path->nodes[level]))
1579 btrfs_item_key_to_cpu(path->nodes[level], key,
1580 path->slots[level] + 1);
1582 btrfs_node_key_to_cpu(path->nodes[level], key,
1583 path->slots[level] + 1);
1590 * look for inline back ref. if back ref is found, *ref_ret is set
1591 * to the address of inline back ref, and 0 is returned.
1593 * if back ref isn't found, *ref_ret is set to the address where it
1594 * should be inserted, and -ENOENT is returned.
1596 * if insert is true and there are too many inline back refs, the path
1597 * points to the extent item, and -EAGAIN is returned.
1599 * NOTE: inline back refs are ordered in the same way that back ref
1600 * items in the tree are ordered.
1602 static noinline_for_stack
1603 int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
1604 struct btrfs_fs_info *fs_info,
1605 struct btrfs_path *path,
1606 struct btrfs_extent_inline_ref **ref_ret,
1607 u64 bytenr, u64 num_bytes,
1608 u64 parent, u64 root_objectid,
1609 u64 owner, u64 offset, int insert)
1611 struct btrfs_root *root = fs_info->extent_root;
1612 struct btrfs_key key;
1613 struct extent_buffer *leaf;
1614 struct btrfs_extent_item *ei;
1615 struct btrfs_extent_inline_ref *iref;
1625 bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
1628 key.objectid = bytenr;
1629 key.type = BTRFS_EXTENT_ITEM_KEY;
1630 key.offset = num_bytes;
1632 want = extent_ref_type(parent, owner);
1634 extra_size = btrfs_extent_inline_ref_size(want);
1635 path->keep_locks = 1;
1640 * Owner is our parent level, so we can just add one to get the level
1641 * for the block we are interested in.
1643 if (skinny_metadata && owner < BTRFS_FIRST_FREE_OBJECTID) {
1644 key.type = BTRFS_METADATA_ITEM_KEY;
1649 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
1656 * We may be a newly converted file system which still has the old fat
1657 * extent entries for metadata, so try and see if we have one of those.
1659 if (ret > 0 && skinny_metadata) {
1660 skinny_metadata = false;
1661 if (path->slots[0]) {
1663 btrfs_item_key_to_cpu(path->nodes[0], &key,
1665 if (key.objectid == bytenr &&
1666 key.type == BTRFS_EXTENT_ITEM_KEY &&
1667 key.offset == num_bytes)
1671 key.objectid = bytenr;
1672 key.type = BTRFS_EXTENT_ITEM_KEY;
1673 key.offset = num_bytes;
1674 btrfs_release_path(path);
1679 if (ret && !insert) {
1682 } else if (WARN_ON(ret)) {
1687 leaf = path->nodes[0];
1688 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1689 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1690 if (item_size < sizeof(*ei)) {
1695 ret = convert_extent_item_v0(trans, fs_info, path, owner,
1701 leaf = path->nodes[0];
1702 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1705 BUG_ON(item_size < sizeof(*ei));
1707 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1708 flags = btrfs_extent_flags(leaf, ei);
1710 ptr = (unsigned long)(ei + 1);
1711 end = (unsigned long)ei + item_size;
1713 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK && !skinny_metadata) {
1714 ptr += sizeof(struct btrfs_tree_block_info);
1718 if (owner >= BTRFS_FIRST_FREE_OBJECTID)
1719 needed = BTRFS_REF_TYPE_DATA;
1721 needed = BTRFS_REF_TYPE_BLOCK;
1729 iref = (struct btrfs_extent_inline_ref *)ptr;
1730 type = btrfs_get_extent_inline_ref_type(leaf, iref, needed);
1731 if (type == BTRFS_REF_TYPE_INVALID) {
1739 ptr += btrfs_extent_inline_ref_size(type);
1743 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1744 struct btrfs_extent_data_ref *dref;
1745 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1746 if (match_extent_data_ref(leaf, dref, root_objectid,
1751 if (hash_extent_data_ref_item(leaf, dref) <
1752 hash_extent_data_ref(root_objectid, owner, offset))
1756 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1758 if (parent == ref_offset) {
1762 if (ref_offset < parent)
1765 if (root_objectid == ref_offset) {
1769 if (ref_offset < root_objectid)
1773 ptr += btrfs_extent_inline_ref_size(type);
1775 if (err == -ENOENT && insert) {
1776 if (item_size + extra_size >=
1777 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
1782 * To add new inline back ref, we have to make sure
1783 * there is no corresponding back ref item.
1784 * For simplicity, we just do not add new inline back
1785 * ref if there is any kind of item for this block
1787 if (find_next_key(path, 0, &key) == 0 &&
1788 key.objectid == bytenr &&
1789 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
1794 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
1797 path->keep_locks = 0;
1798 btrfs_unlock_up_safe(path, 1);
1804 * helper to add new inline back ref
1806 static noinline_for_stack
1807 void setup_inline_extent_backref(struct btrfs_fs_info *fs_info,
1808 struct btrfs_path *path,
1809 struct btrfs_extent_inline_ref *iref,
1810 u64 parent, u64 root_objectid,
1811 u64 owner, u64 offset, int refs_to_add,
1812 struct btrfs_delayed_extent_op *extent_op)
1814 struct extent_buffer *leaf;
1815 struct btrfs_extent_item *ei;
1818 unsigned long item_offset;
1823 leaf = path->nodes[0];
1824 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1825 item_offset = (unsigned long)iref - (unsigned long)ei;
1827 type = extent_ref_type(parent, owner);
1828 size = btrfs_extent_inline_ref_size(type);
1830 btrfs_extend_item(fs_info, path, size);
1832 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1833 refs = btrfs_extent_refs(leaf, ei);
1834 refs += refs_to_add;
1835 btrfs_set_extent_refs(leaf, ei, refs);
1837 __run_delayed_extent_op(extent_op, leaf, ei);
1839 ptr = (unsigned long)ei + item_offset;
1840 end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
1841 if (ptr < end - size)
1842 memmove_extent_buffer(leaf, ptr + size, ptr,
1845 iref = (struct btrfs_extent_inline_ref *)ptr;
1846 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1847 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1848 struct btrfs_extent_data_ref *dref;
1849 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1850 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1851 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1852 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1853 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1854 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1855 struct btrfs_shared_data_ref *sref;
1856 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1857 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1858 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1859 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1860 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1862 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1864 btrfs_mark_buffer_dirty(leaf);
1867 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1868 struct btrfs_fs_info *fs_info,
1869 struct btrfs_path *path,
1870 struct btrfs_extent_inline_ref **ref_ret,
1871 u64 bytenr, u64 num_bytes, u64 parent,
1872 u64 root_objectid, u64 owner, u64 offset)
1876 ret = lookup_inline_extent_backref(trans, fs_info, path, ref_ret,
1877 bytenr, num_bytes, parent,
1878 root_objectid, owner, offset, 0);
1882 btrfs_release_path(path);
1885 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1886 ret = lookup_tree_block_ref(trans, fs_info, path, bytenr,
1887 parent, root_objectid);
1889 ret = lookup_extent_data_ref(trans, fs_info, path, bytenr,
1890 parent, root_objectid, owner,
1897 * helper to update/remove inline back ref
1899 static noinline_for_stack
1900 void update_inline_extent_backref(struct btrfs_fs_info *fs_info,
1901 struct btrfs_path *path,
1902 struct btrfs_extent_inline_ref *iref,
1904 struct btrfs_delayed_extent_op *extent_op,
1907 struct extent_buffer *leaf;
1908 struct btrfs_extent_item *ei;
1909 struct btrfs_extent_data_ref *dref = NULL;
1910 struct btrfs_shared_data_ref *sref = NULL;
1918 leaf = path->nodes[0];
1919 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1920 refs = btrfs_extent_refs(leaf, ei);
1921 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1922 refs += refs_to_mod;
1923 btrfs_set_extent_refs(leaf, ei, refs);
1925 __run_delayed_extent_op(extent_op, leaf, ei);
1928 * If type is invalid, we should have bailed out after
1929 * lookup_inline_extent_backref().
1931 type = btrfs_get_extent_inline_ref_type(leaf, iref, BTRFS_REF_TYPE_ANY);
1932 ASSERT(type != BTRFS_REF_TYPE_INVALID);
1934 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1935 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1936 refs = btrfs_extent_data_ref_count(leaf, dref);
1937 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1938 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1939 refs = btrfs_shared_data_ref_count(leaf, sref);
1942 BUG_ON(refs_to_mod != -1);
1945 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1946 refs += refs_to_mod;
1949 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1950 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1952 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1955 size = btrfs_extent_inline_ref_size(type);
1956 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1957 ptr = (unsigned long)iref;
1958 end = (unsigned long)ei + item_size;
1959 if (ptr + size < end)
1960 memmove_extent_buffer(leaf, ptr, ptr + size,
1963 btrfs_truncate_item(fs_info, path, item_size, 1);
1965 btrfs_mark_buffer_dirty(leaf);
1968 static noinline_for_stack
1969 int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1970 struct btrfs_fs_info *fs_info,
1971 struct btrfs_path *path,
1972 u64 bytenr, u64 num_bytes, u64 parent,
1973 u64 root_objectid, u64 owner,
1974 u64 offset, int refs_to_add,
1975 struct btrfs_delayed_extent_op *extent_op)
1977 struct btrfs_extent_inline_ref *iref;
1980 ret = lookup_inline_extent_backref(trans, fs_info, path, &iref,
1981 bytenr, num_bytes, parent,
1982 root_objectid, owner, offset, 1);
1984 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
1985 update_inline_extent_backref(fs_info, path, iref,
1986 refs_to_add, extent_op, NULL);
1987 } else if (ret == -ENOENT) {
1988 setup_inline_extent_backref(fs_info, path, iref, parent,
1989 root_objectid, owner, offset,
1990 refs_to_add, extent_op);
1996 static int insert_extent_backref(struct btrfs_trans_handle *trans,
1997 struct btrfs_fs_info *fs_info,
1998 struct btrfs_path *path,
1999 u64 bytenr, u64 parent, u64 root_objectid,
2000 u64 owner, u64 offset, int refs_to_add)
2003 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
2004 BUG_ON(refs_to_add != 1);
2005 ret = insert_tree_block_ref(trans, fs_info, path, bytenr,
2006 parent, root_objectid);
2008 ret = insert_extent_data_ref(trans, fs_info, path, bytenr,
2009 parent, root_objectid,
2010 owner, offset, refs_to_add);
2015 static int remove_extent_backref(struct btrfs_trans_handle *trans,
2016 struct btrfs_fs_info *fs_info,
2017 struct btrfs_path *path,
2018 struct btrfs_extent_inline_ref *iref,
2019 int refs_to_drop, int is_data, int *last_ref)
2023 BUG_ON(!is_data && refs_to_drop != 1);
2025 update_inline_extent_backref(fs_info, path, iref,
2026 -refs_to_drop, NULL, last_ref);
2027 } else if (is_data) {
2028 ret = remove_extent_data_ref(trans, fs_info, path, refs_to_drop,
2032 ret = btrfs_del_item(trans, fs_info->extent_root, path);
2037 #define in_range(b, first, len) ((b) >= (first) && (b) < (first) + (len))
2038 static int btrfs_issue_discard(struct block_device *bdev, u64 start, u64 len,
2039 u64 *discarded_bytes)
2042 u64 bytes_left, end;
2043 u64 aligned_start = ALIGN(start, 1 << 9);
2045 if (WARN_ON(start != aligned_start)) {
2046 len -= aligned_start - start;
2047 len = round_down(len, 1 << 9);
2048 start = aligned_start;
2051 *discarded_bytes = 0;
2059 /* Skip any superblocks on this device. */
2060 for (j = 0; j < BTRFS_SUPER_MIRROR_MAX; j++) {
2061 u64 sb_start = btrfs_sb_offset(j);
2062 u64 sb_end = sb_start + BTRFS_SUPER_INFO_SIZE;
2063 u64 size = sb_start - start;
2065 if (!in_range(sb_start, start, bytes_left) &&
2066 !in_range(sb_end, start, bytes_left) &&
2067 !in_range(start, sb_start, BTRFS_SUPER_INFO_SIZE))
2071 * Superblock spans beginning of range. Adjust start and
2074 if (sb_start <= start) {
2075 start += sb_end - start;
2080 bytes_left = end - start;
2085 ret = blkdev_issue_discard(bdev, start >> 9, size >> 9,
2088 *discarded_bytes += size;
2089 else if (ret != -EOPNOTSUPP)
2098 bytes_left = end - start;
2102 ret = blkdev_issue_discard(bdev, start >> 9, bytes_left >> 9,
2105 *discarded_bytes += bytes_left;
2110 int btrfs_discard_extent(struct btrfs_fs_info *fs_info, u64 bytenr,
2111 u64 num_bytes, u64 *actual_bytes)
2114 u64 discarded_bytes = 0;
2115 struct btrfs_bio *bbio = NULL;
2119 * Avoid races with device replace and make sure our bbio has devices
2120 * associated to its stripes that don't go away while we are discarding.
2122 btrfs_bio_counter_inc_blocked(fs_info);
2123 /* Tell the block device(s) that the sectors can be discarded */
2124 ret = btrfs_map_block(fs_info, BTRFS_MAP_DISCARD, bytenr, &num_bytes,
2126 /* Error condition is -ENOMEM */
2128 struct btrfs_bio_stripe *stripe = bbio->stripes;
2132 for (i = 0; i < bbio->num_stripes; i++, stripe++) {
2134 struct request_queue *req_q;
2136 if (!stripe->dev->bdev) {
2137 ASSERT(btrfs_test_opt(fs_info, DEGRADED));
2140 req_q = bdev_get_queue(stripe->dev->bdev);
2141 if (!blk_queue_discard(req_q))
2144 ret = btrfs_issue_discard(stripe->dev->bdev,
2149 discarded_bytes += bytes;
2150 else if (ret != -EOPNOTSUPP)
2151 break; /* Logic errors or -ENOMEM, or -EIO but I don't know how that could happen JDM */
2154 * Just in case we get back EOPNOTSUPP for some reason,
2155 * just ignore the return value so we don't screw up
2156 * people calling discard_extent.
2160 btrfs_put_bbio(bbio);
2162 btrfs_bio_counter_dec(fs_info);
2165 *actual_bytes = discarded_bytes;
2168 if (ret == -EOPNOTSUPP)
2173 /* Can return -ENOMEM */
2174 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
2175 struct btrfs_root *root,
2176 u64 bytenr, u64 num_bytes, u64 parent,
2177 u64 root_objectid, u64 owner, u64 offset)
2179 struct btrfs_fs_info *fs_info = root->fs_info;
2180 int old_ref_mod, new_ref_mod;
2183 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID &&
2184 root_objectid == BTRFS_TREE_LOG_OBJECTID);
2186 btrfs_ref_tree_mod(root, bytenr, num_bytes, parent, root_objectid,
2187 owner, offset, BTRFS_ADD_DELAYED_REF);
2189 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
2190 ret = btrfs_add_delayed_tree_ref(fs_info, trans, bytenr,
2192 root_objectid, (int)owner,
2193 BTRFS_ADD_DELAYED_REF, NULL,
2194 &old_ref_mod, &new_ref_mod);
2196 ret = btrfs_add_delayed_data_ref(fs_info, trans, bytenr,
2198 root_objectid, owner, offset,
2199 0, BTRFS_ADD_DELAYED_REF,
2200 &old_ref_mod, &new_ref_mod);
2203 if (ret == 0 && old_ref_mod < 0 && new_ref_mod >= 0)
2204 add_pinned_bytes(fs_info, -num_bytes, owner, root_objectid);
2209 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
2210 struct btrfs_fs_info *fs_info,
2211 struct btrfs_delayed_ref_node *node,
2212 u64 parent, u64 root_objectid,
2213 u64 owner, u64 offset, int refs_to_add,
2214 struct btrfs_delayed_extent_op *extent_op)
2216 struct btrfs_path *path;
2217 struct extent_buffer *leaf;
2218 struct btrfs_extent_item *item;
2219 struct btrfs_key key;
2220 u64 bytenr = node->bytenr;
2221 u64 num_bytes = node->num_bytes;
2225 path = btrfs_alloc_path();
2229 path->reada = READA_FORWARD;
2230 path->leave_spinning = 1;
2231 /* this will setup the path even if it fails to insert the back ref */
2232 ret = insert_inline_extent_backref(trans, fs_info, path, bytenr,
2233 num_bytes, parent, root_objectid,
2235 refs_to_add, extent_op);
2236 if ((ret < 0 && ret != -EAGAIN) || !ret)
2240 * Ok we had -EAGAIN which means we didn't have space to insert and
2241 * inline extent ref, so just update the reference count and add a
2244 leaf = path->nodes[0];
2245 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2246 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2247 refs = btrfs_extent_refs(leaf, item);
2248 btrfs_set_extent_refs(leaf, item, refs + refs_to_add);
2250 __run_delayed_extent_op(extent_op, leaf, item);
2252 btrfs_mark_buffer_dirty(leaf);
2253 btrfs_release_path(path);
2255 path->reada = READA_FORWARD;
2256 path->leave_spinning = 1;
2257 /* now insert the actual backref */
2258 ret = insert_extent_backref(trans, fs_info, path, bytenr, parent,
2259 root_objectid, owner, offset, refs_to_add);
2261 btrfs_abort_transaction(trans, ret);
2263 btrfs_free_path(path);
2267 static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
2268 struct btrfs_fs_info *fs_info,
2269 struct btrfs_delayed_ref_node *node,
2270 struct btrfs_delayed_extent_op *extent_op,
2271 int insert_reserved)
2274 struct btrfs_delayed_data_ref *ref;
2275 struct btrfs_key ins;
2280 ins.objectid = node->bytenr;
2281 ins.offset = node->num_bytes;
2282 ins.type = BTRFS_EXTENT_ITEM_KEY;
2284 ref = btrfs_delayed_node_to_data_ref(node);
2285 trace_run_delayed_data_ref(fs_info, node, ref, node->action);
2287 if (node->type == BTRFS_SHARED_DATA_REF_KEY)
2288 parent = ref->parent;
2289 ref_root = ref->root;
2291 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
2293 flags |= extent_op->flags_to_set;
2294 ret = alloc_reserved_file_extent(trans, fs_info,
2295 parent, ref_root, flags,
2296 ref->objectid, ref->offset,
2297 &ins, node->ref_mod);
2298 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
2299 ret = __btrfs_inc_extent_ref(trans, fs_info, node, parent,
2300 ref_root, ref->objectid,
2301 ref->offset, node->ref_mod,
2303 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
2304 ret = __btrfs_free_extent(trans, fs_info, node, parent,
2305 ref_root, ref->objectid,
2306 ref->offset, node->ref_mod,
2314 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
2315 struct extent_buffer *leaf,
2316 struct btrfs_extent_item *ei)
2318 u64 flags = btrfs_extent_flags(leaf, ei);
2319 if (extent_op->update_flags) {
2320 flags |= extent_op->flags_to_set;
2321 btrfs_set_extent_flags(leaf, ei, flags);
2324 if (extent_op->update_key) {
2325 struct btrfs_tree_block_info *bi;
2326 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK));
2327 bi = (struct btrfs_tree_block_info *)(ei + 1);
2328 btrfs_set_tree_block_key(leaf, bi, &extent_op->key);
2332 static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
2333 struct btrfs_fs_info *fs_info,
2334 struct btrfs_delayed_ref_head *head,
2335 struct btrfs_delayed_extent_op *extent_op)
2337 struct btrfs_key key;
2338 struct btrfs_path *path;
2339 struct btrfs_extent_item *ei;
2340 struct extent_buffer *leaf;
2344 int metadata = !extent_op->is_data;
2349 if (metadata && !btrfs_fs_incompat(fs_info, SKINNY_METADATA))
2352 path = btrfs_alloc_path();
2356 key.objectid = head->bytenr;
2359 key.type = BTRFS_METADATA_ITEM_KEY;
2360 key.offset = extent_op->level;
2362 key.type = BTRFS_EXTENT_ITEM_KEY;
2363 key.offset = head->num_bytes;
2367 path->reada = READA_FORWARD;
2368 path->leave_spinning = 1;
2369 ret = btrfs_search_slot(trans, fs_info->extent_root, &key, path, 0, 1);
2376 if (path->slots[0] > 0) {
2378 btrfs_item_key_to_cpu(path->nodes[0], &key,
2380 if (key.objectid == head->bytenr &&
2381 key.type == BTRFS_EXTENT_ITEM_KEY &&
2382 key.offset == head->num_bytes)
2386 btrfs_release_path(path);
2389 key.objectid = head->bytenr;
2390 key.offset = head->num_bytes;
2391 key.type = BTRFS_EXTENT_ITEM_KEY;
2400 leaf = path->nodes[0];
2401 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2402 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2403 if (item_size < sizeof(*ei)) {
2404 ret = convert_extent_item_v0(trans, fs_info, path, (u64)-1, 0);
2409 leaf = path->nodes[0];
2410 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2413 BUG_ON(item_size < sizeof(*ei));
2414 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2415 __run_delayed_extent_op(extent_op, leaf, ei);
2417 btrfs_mark_buffer_dirty(leaf);
2419 btrfs_free_path(path);
2423 static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
2424 struct btrfs_fs_info *fs_info,
2425 struct btrfs_delayed_ref_node *node,
2426 struct btrfs_delayed_extent_op *extent_op,
2427 int insert_reserved)
2430 struct btrfs_delayed_tree_ref *ref;
2431 struct btrfs_key ins;
2434 bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
2436 ref = btrfs_delayed_node_to_tree_ref(node);
2437 trace_run_delayed_tree_ref(fs_info, node, ref, node->action);
2439 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2440 parent = ref->parent;
2441 ref_root = ref->root;
2443 ins.objectid = node->bytenr;
2444 if (skinny_metadata) {
2445 ins.offset = ref->level;
2446 ins.type = BTRFS_METADATA_ITEM_KEY;
2448 ins.offset = node->num_bytes;
2449 ins.type = BTRFS_EXTENT_ITEM_KEY;
2452 if (node->ref_mod != 1) {
2454 "btree block(%llu) has %d references rather than 1: action %d ref_root %llu parent %llu",
2455 node->bytenr, node->ref_mod, node->action, ref_root,
2459 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
2460 BUG_ON(!extent_op || !extent_op->update_flags);
2461 ret = alloc_reserved_tree_block(trans, fs_info,
2463 extent_op->flags_to_set,
2466 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
2467 ret = __btrfs_inc_extent_ref(trans, fs_info, node,
2471 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
2472 ret = __btrfs_free_extent(trans, fs_info, node,
2474 ref->level, 0, 1, extent_op);
2481 /* helper function to actually process a single delayed ref entry */
2482 static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
2483 struct btrfs_fs_info *fs_info,
2484 struct btrfs_delayed_ref_node *node,
2485 struct btrfs_delayed_extent_op *extent_op,
2486 int insert_reserved)
2490 if (trans->aborted) {
2491 if (insert_reserved)
2492 btrfs_pin_extent(fs_info, node->bytenr,
2493 node->num_bytes, 1);
2497 if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
2498 node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2499 ret = run_delayed_tree_ref(trans, fs_info, node, extent_op,
2501 else if (node->type == BTRFS_EXTENT_DATA_REF_KEY ||
2502 node->type == BTRFS_SHARED_DATA_REF_KEY)
2503 ret = run_delayed_data_ref(trans, fs_info, node, extent_op,
2510 static inline struct btrfs_delayed_ref_node *
2511 select_delayed_ref(struct btrfs_delayed_ref_head *head)
2513 struct btrfs_delayed_ref_node *ref;
2515 if (RB_EMPTY_ROOT(&head->ref_tree))
2519 * Select a delayed ref of type BTRFS_ADD_DELAYED_REF first.
2520 * This is to prevent a ref count from going down to zero, which deletes
2521 * the extent item from the extent tree, when there still are references
2522 * to add, which would fail because they would not find the extent item.
2524 if (!list_empty(&head->ref_add_list))
2525 return list_first_entry(&head->ref_add_list,
2526 struct btrfs_delayed_ref_node, add_list);
2528 ref = rb_entry(rb_first(&head->ref_tree),
2529 struct btrfs_delayed_ref_node, ref_node);
2530 ASSERT(list_empty(&ref->add_list));
2534 static void unselect_delayed_ref_head(struct btrfs_delayed_ref_root *delayed_refs,
2535 struct btrfs_delayed_ref_head *head)
2537 spin_lock(&delayed_refs->lock);
2538 head->processing = 0;
2539 delayed_refs->num_heads_ready++;
2540 spin_unlock(&delayed_refs->lock);
2541 btrfs_delayed_ref_unlock(head);
2544 static int cleanup_extent_op(struct btrfs_trans_handle *trans,
2545 struct btrfs_fs_info *fs_info,
2546 struct btrfs_delayed_ref_head *head)
2548 struct btrfs_delayed_extent_op *extent_op = head->extent_op;
2553 head->extent_op = NULL;
2554 if (head->must_insert_reserved) {
2555 btrfs_free_delayed_extent_op(extent_op);
2558 spin_unlock(&head->lock);
2559 ret = run_delayed_extent_op(trans, fs_info, head, extent_op);
2560 btrfs_free_delayed_extent_op(extent_op);
2561 return ret ? ret : 1;
2564 static int cleanup_ref_head(struct btrfs_trans_handle *trans,
2565 struct btrfs_fs_info *fs_info,
2566 struct btrfs_delayed_ref_head *head)
2568 struct btrfs_delayed_ref_root *delayed_refs;
2571 delayed_refs = &trans->transaction->delayed_refs;
2573 ret = cleanup_extent_op(trans, fs_info, head);
2575 unselect_delayed_ref_head(delayed_refs, head);
2576 btrfs_debug(fs_info, "run_delayed_extent_op returned %d", ret);
2583 * Need to drop our head ref lock and re-acquire the delayed ref lock
2584 * and then re-check to make sure nobody got added.
2586 spin_unlock(&head->lock);
2587 spin_lock(&delayed_refs->lock);
2588 spin_lock(&head->lock);
2589 if (!RB_EMPTY_ROOT(&head->ref_tree) || head->extent_op) {
2590 spin_unlock(&head->lock);
2591 spin_unlock(&delayed_refs->lock);
2594 delayed_refs->num_heads--;
2595 rb_erase(&head->href_node, &delayed_refs->href_root);
2596 RB_CLEAR_NODE(&head->href_node);
2597 spin_unlock(&delayed_refs->lock);
2598 spin_unlock(&head->lock);
2599 atomic_dec(&delayed_refs->num_entries);
2601 trace_run_delayed_ref_head(fs_info, head, 0);
2603 if (head->total_ref_mod < 0) {
2604 struct btrfs_space_info *space_info;
2608 flags = BTRFS_BLOCK_GROUP_DATA;
2609 else if (head->is_system)
2610 flags = BTRFS_BLOCK_GROUP_SYSTEM;
2612 flags = BTRFS_BLOCK_GROUP_METADATA;
2613 space_info = __find_space_info(fs_info, flags);
2615 percpu_counter_add(&space_info->total_bytes_pinned,
2618 if (head->is_data) {
2619 spin_lock(&delayed_refs->lock);
2620 delayed_refs->pending_csums -= head->num_bytes;
2621 spin_unlock(&delayed_refs->lock);
2625 if (head->must_insert_reserved) {
2626 btrfs_pin_extent(fs_info, head->bytenr,
2627 head->num_bytes, 1);
2628 if (head->is_data) {
2629 ret = btrfs_del_csums(trans, fs_info, head->bytenr,
2634 /* Also free its reserved qgroup space */
2635 btrfs_qgroup_free_delayed_ref(fs_info, head->qgroup_ref_root,
2636 head->qgroup_reserved);
2637 btrfs_delayed_ref_unlock(head);
2638 btrfs_put_delayed_ref_head(head);
2643 * Returns 0 on success or if called with an already aborted transaction.
2644 * Returns -ENOMEM or -EIO on failure and will abort the transaction.
2646 static noinline int __btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2649 struct btrfs_fs_info *fs_info = trans->fs_info;
2650 struct btrfs_delayed_ref_root *delayed_refs;
2651 struct btrfs_delayed_ref_node *ref;
2652 struct btrfs_delayed_ref_head *locked_ref = NULL;
2653 struct btrfs_delayed_extent_op *extent_op;
2654 ktime_t start = ktime_get();
2656 unsigned long count = 0;
2657 unsigned long actual_count = 0;
2658 int must_insert_reserved = 0;
2660 delayed_refs = &trans->transaction->delayed_refs;
2666 spin_lock(&delayed_refs->lock);
2667 locked_ref = btrfs_select_ref_head(trans);
2669 spin_unlock(&delayed_refs->lock);
2673 /* grab the lock that says we are going to process
2674 * all the refs for this head */
2675 ret = btrfs_delayed_ref_lock(trans, locked_ref);
2676 spin_unlock(&delayed_refs->lock);
2678 * we may have dropped the spin lock to get the head
2679 * mutex lock, and that might have given someone else
2680 * time to free the head. If that's true, it has been
2681 * removed from our list and we can move on.
2683 if (ret == -EAGAIN) {
2691 * We need to try and merge add/drops of the same ref since we
2692 * can run into issues with relocate dropping the implicit ref
2693 * and then it being added back again before the drop can
2694 * finish. If we merged anything we need to re-loop so we can
2696 * Or we can get node references of the same type that weren't
2697 * merged when created due to bumps in the tree mod seq, and
2698 * we need to merge them to prevent adding an inline extent
2699 * backref before dropping it (triggering a BUG_ON at
2700 * insert_inline_extent_backref()).
2702 spin_lock(&locked_ref->lock);
2703 btrfs_merge_delayed_refs(trans, fs_info, delayed_refs,
2707 * locked_ref is the head node, so we have to go one
2708 * node back for any delayed ref updates
2710 ref = select_delayed_ref(locked_ref);
2712 if (ref && ref->seq &&
2713 btrfs_check_delayed_seq(fs_info, delayed_refs, ref->seq)) {
2714 spin_unlock(&locked_ref->lock);
2715 unselect_delayed_ref_head(delayed_refs, locked_ref);
2723 * We're done processing refs in this ref_head, clean everything
2724 * up and move on to the next ref_head.
2727 ret = cleanup_ref_head(trans, fs_info, locked_ref);
2729 /* We dropped our lock, we need to loop. */
2742 rb_erase(&ref->ref_node, &locked_ref->ref_tree);
2743 RB_CLEAR_NODE(&ref->ref_node);
2744 if (!list_empty(&ref->add_list))
2745 list_del(&ref->add_list);
2747 * When we play the delayed ref, also correct the ref_mod on
2750 switch (ref->action) {
2751 case BTRFS_ADD_DELAYED_REF:
2752 case BTRFS_ADD_DELAYED_EXTENT:
2753 locked_ref->ref_mod -= ref->ref_mod;
2755 case BTRFS_DROP_DELAYED_REF:
2756 locked_ref->ref_mod += ref->ref_mod;
2761 atomic_dec(&delayed_refs->num_entries);
2764 * Record the must-insert_reserved flag before we drop the spin
2767 must_insert_reserved = locked_ref->must_insert_reserved;
2768 locked_ref->must_insert_reserved = 0;
2770 extent_op = locked_ref->extent_op;
2771 locked_ref->extent_op = NULL;
2772 spin_unlock(&locked_ref->lock);
2774 ret = run_one_delayed_ref(trans, fs_info, ref, extent_op,
2775 must_insert_reserved);
2777 btrfs_free_delayed_extent_op(extent_op);
2779 unselect_delayed_ref_head(delayed_refs, locked_ref);
2780 btrfs_put_delayed_ref(ref);
2781 btrfs_debug(fs_info, "run_one_delayed_ref returned %d",
2786 btrfs_put_delayed_ref(ref);
2792 * We don't want to include ref heads since we can have empty ref heads
2793 * and those will drastically skew our runtime down since we just do
2794 * accounting, no actual extent tree updates.
2796 if (actual_count > 0) {
2797 u64 runtime = ktime_to_ns(ktime_sub(ktime_get(), start));
2801 * We weigh the current average higher than our current runtime
2802 * to avoid large swings in the average.
2804 spin_lock(&delayed_refs->lock);
2805 avg = fs_info->avg_delayed_ref_runtime * 3 + runtime;
2806 fs_info->avg_delayed_ref_runtime = avg >> 2; /* div by 4 */
2807 spin_unlock(&delayed_refs->lock);
2812 #ifdef SCRAMBLE_DELAYED_REFS
2814 * Normally delayed refs get processed in ascending bytenr order. This
2815 * correlates in most cases to the order added. To expose dependencies on this
2816 * order, we start to process the tree in the middle instead of the beginning
2818 static u64 find_middle(struct rb_root *root)
2820 struct rb_node *n = root->rb_node;
2821 struct btrfs_delayed_ref_node *entry;
2824 u64 first = 0, last = 0;
2828 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2829 first = entry->bytenr;
2833 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2834 last = entry->bytenr;
2839 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2840 WARN_ON(!entry->in_tree);
2842 middle = entry->bytenr;
2855 static inline u64 heads_to_leaves(struct btrfs_fs_info *fs_info, u64 heads)
2859 num_bytes = heads * (sizeof(struct btrfs_extent_item) +
2860 sizeof(struct btrfs_extent_inline_ref));
2861 if (!btrfs_fs_incompat(fs_info, SKINNY_METADATA))
2862 num_bytes += heads * sizeof(struct btrfs_tree_block_info);
2865 * We don't ever fill up leaves all the way so multiply by 2 just to be
2866 * closer to what we're really going to want to use.
2868 return div_u64(num_bytes, BTRFS_LEAF_DATA_SIZE(fs_info));
2872 * Takes the number of bytes to be csumm'ed and figures out how many leaves it
2873 * would require to store the csums for that many bytes.
2875 u64 btrfs_csum_bytes_to_leaves(struct btrfs_fs_info *fs_info, u64 csum_bytes)
2878 u64 num_csums_per_leaf;
2881 csum_size = BTRFS_MAX_ITEM_SIZE(fs_info);
2882 num_csums_per_leaf = div64_u64(csum_size,
2883 (u64)btrfs_super_csum_size(fs_info->super_copy));
2884 num_csums = div64_u64(csum_bytes, fs_info->sectorsize);
2885 num_csums += num_csums_per_leaf - 1;
2886 num_csums = div64_u64(num_csums, num_csums_per_leaf);
2890 int btrfs_check_space_for_delayed_refs(struct btrfs_trans_handle *trans,
2891 struct btrfs_fs_info *fs_info)
2893 struct btrfs_block_rsv *global_rsv;
2894 u64 num_heads = trans->transaction->delayed_refs.num_heads_ready;
2895 u64 csum_bytes = trans->transaction->delayed_refs.pending_csums;
2896 unsigned int num_dirty_bgs = trans->transaction->num_dirty_bgs;
2897 u64 num_bytes, num_dirty_bgs_bytes;
2900 num_bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
2901 num_heads = heads_to_leaves(fs_info, num_heads);
2903 num_bytes += (num_heads - 1) * fs_info->nodesize;
2905 num_bytes += btrfs_csum_bytes_to_leaves(fs_info, csum_bytes) *
2907 num_dirty_bgs_bytes = btrfs_calc_trans_metadata_size(fs_info,
2909 global_rsv = &fs_info->global_block_rsv;
2912 * If we can't allocate any more chunks lets make sure we have _lots_ of
2913 * wiggle room since running delayed refs can create more delayed refs.
2915 if (global_rsv->space_info->full) {
2916 num_dirty_bgs_bytes <<= 1;
2920 spin_lock(&global_rsv->lock);
2921 if (global_rsv->reserved <= num_bytes + num_dirty_bgs_bytes)
2923 spin_unlock(&global_rsv->lock);
2927 int btrfs_should_throttle_delayed_refs(struct btrfs_trans_handle *trans,
2928 struct btrfs_fs_info *fs_info)
2931 atomic_read(&trans->transaction->delayed_refs.num_entries);
2936 avg_runtime = fs_info->avg_delayed_ref_runtime;
2937 val = num_entries * avg_runtime;
2938 if (val >= NSEC_PER_SEC)
2940 if (val >= NSEC_PER_SEC / 2)
2943 return btrfs_check_space_for_delayed_refs(trans, fs_info);
2946 struct async_delayed_refs {
2947 struct btrfs_root *root;
2952 struct completion wait;
2953 struct btrfs_work work;
2956 static inline struct async_delayed_refs *
2957 to_async_delayed_refs(struct btrfs_work *work)
2959 return container_of(work, struct async_delayed_refs, work);
2962 static void delayed_ref_async_start(struct btrfs_work *work)
2964 struct async_delayed_refs *async = to_async_delayed_refs(work);
2965 struct btrfs_trans_handle *trans;
2966 struct btrfs_fs_info *fs_info = async->root->fs_info;
2969 /* if the commit is already started, we don't need to wait here */
2970 if (btrfs_transaction_blocked(fs_info))
2973 trans = btrfs_join_transaction(async->root);
2974 if (IS_ERR(trans)) {
2975 async->error = PTR_ERR(trans);
2980 * trans->sync means that when we call end_transaction, we won't
2981 * wait on delayed refs
2985 /* Don't bother flushing if we got into a different transaction */
2986 if (trans->transid > async->transid)
2989 ret = btrfs_run_delayed_refs(trans, async->count);
2993 ret = btrfs_end_transaction(trans);
2994 if (ret && !async->error)
2998 complete(&async->wait);
3003 int btrfs_async_run_delayed_refs(struct btrfs_fs_info *fs_info,
3004 unsigned long count, u64 transid, int wait)
3006 struct async_delayed_refs *async;
3009 async = kmalloc(sizeof(*async), GFP_NOFS);
3013 async->root = fs_info->tree_root;
3014 async->count = count;
3016 async->transid = transid;
3021 init_completion(&async->wait);
3023 btrfs_init_work(&async->work, btrfs_extent_refs_helper,
3024 delayed_ref_async_start, NULL, NULL);
3026 btrfs_queue_work(fs_info->extent_workers, &async->work);
3029 wait_for_completion(&async->wait);
3038 * this starts processing the delayed reference count updates and
3039 * extent insertions we have queued up so far. count can be
3040 * 0, which means to process everything in the tree at the start
3041 * of the run (but not newly added entries), or it can be some target
3042 * number you'd like to process.
3044 * Returns 0 on success or if called with an aborted transaction
3045 * Returns <0 on error and aborts the transaction
3047 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
3048 unsigned long count)
3050 struct btrfs_fs_info *fs_info = trans->fs_info;
3051 struct rb_node *node;
3052 struct btrfs_delayed_ref_root *delayed_refs;
3053 struct btrfs_delayed_ref_head *head;
3055 int run_all = count == (unsigned long)-1;
3056 bool can_flush_pending_bgs = trans->can_flush_pending_bgs;
3058 /* We'll clean this up in btrfs_cleanup_transaction */
3062 if (test_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags))
3065 delayed_refs = &trans->transaction->delayed_refs;
3067 count = atomic_read(&delayed_refs->num_entries) * 2;
3070 #ifdef SCRAMBLE_DELAYED_REFS
3071 delayed_refs->run_delayed_start = find_middle(&delayed_refs->root);
3073 trans->can_flush_pending_bgs = false;
3074 ret = __btrfs_run_delayed_refs(trans, count);
3076 btrfs_abort_transaction(trans, ret);
3081 if (!list_empty(&trans->new_bgs))
3082 btrfs_create_pending_block_groups(trans);
3084 spin_lock(&delayed_refs->lock);
3085 node = rb_first(&delayed_refs->href_root);
3087 spin_unlock(&delayed_refs->lock);
3090 head = rb_entry(node, struct btrfs_delayed_ref_head,
3092 refcount_inc(&head->refs);
3093 spin_unlock(&delayed_refs->lock);
3095 /* Mutex was contended, block until it's released and retry. */
3096 mutex_lock(&head->mutex);
3097 mutex_unlock(&head->mutex);
3099 btrfs_put_delayed_ref_head(head);
3104 trans->can_flush_pending_bgs = can_flush_pending_bgs;
3108 int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
3109 struct btrfs_fs_info *fs_info,
3110 u64 bytenr, u64 num_bytes, u64 flags,
3111 int level, int is_data)
3113 struct btrfs_delayed_extent_op *extent_op;
3116 extent_op = btrfs_alloc_delayed_extent_op();
3120 extent_op->flags_to_set = flags;
3121 extent_op->update_flags = true;
3122 extent_op->update_key = false;
3123 extent_op->is_data = is_data ? true : false;
3124 extent_op->level = level;
3126 ret = btrfs_add_delayed_extent_op(fs_info, trans, bytenr,
3127 num_bytes, extent_op);
3129 btrfs_free_delayed_extent_op(extent_op);
3133 static noinline int check_delayed_ref(struct btrfs_root *root,
3134 struct btrfs_path *path,
3135 u64 objectid, u64 offset, u64 bytenr)
3137 struct btrfs_delayed_ref_head *head;
3138 struct btrfs_delayed_ref_node *ref;
3139 struct btrfs_delayed_data_ref *data_ref;
3140 struct btrfs_delayed_ref_root *delayed_refs;
3141 struct btrfs_transaction *cur_trans;
3142 struct rb_node *node;
3145 spin_lock(&root->fs_info->trans_lock);
3146 cur_trans = root->fs_info->running_transaction;
3148 refcount_inc(&cur_trans->use_count);
3149 spin_unlock(&root->fs_info->trans_lock);
3153 delayed_refs = &cur_trans->delayed_refs;
3154 spin_lock(&delayed_refs->lock);
3155 head = btrfs_find_delayed_ref_head(delayed_refs, bytenr);
3157 spin_unlock(&delayed_refs->lock);
3158 btrfs_put_transaction(cur_trans);
3162 if (!mutex_trylock(&head->mutex)) {
3163 refcount_inc(&head->refs);
3164 spin_unlock(&delayed_refs->lock);
3166 btrfs_release_path(path);
3169 * Mutex was contended, block until it's released and let
3172 mutex_lock(&head->mutex);
3173 mutex_unlock(&head->mutex);
3174 btrfs_put_delayed_ref_head(head);
3175 btrfs_put_transaction(cur_trans);
3178 spin_unlock(&delayed_refs->lock);
3180 spin_lock(&head->lock);
3182 * XXX: We should replace this with a proper search function in the
3185 for (node = rb_first(&head->ref_tree); node; node = rb_next(node)) {
3186 ref = rb_entry(node, struct btrfs_delayed_ref_node, ref_node);
3187 /* If it's a shared ref we know a cross reference exists */
3188 if (ref->type != BTRFS_EXTENT_DATA_REF_KEY) {
3193 data_ref = btrfs_delayed_node_to_data_ref(ref);
3196 * If our ref doesn't match the one we're currently looking at
3197 * then we have a cross reference.
3199 if (data_ref->root != root->root_key.objectid ||
3200 data_ref->objectid != objectid ||
3201 data_ref->offset != offset) {
3206 spin_unlock(&head->lock);
3207 mutex_unlock(&head->mutex);
3208 btrfs_put_transaction(cur_trans);
3212 static noinline int check_committed_ref(struct btrfs_root *root,
3213 struct btrfs_path *path,
3214 u64 objectid, u64 offset, u64 bytenr)
3216 struct btrfs_fs_info *fs_info = root->fs_info;
3217 struct btrfs_root *extent_root = fs_info->extent_root;
3218 struct extent_buffer *leaf;
3219 struct btrfs_extent_data_ref *ref;
3220 struct btrfs_extent_inline_ref *iref;
3221 struct btrfs_extent_item *ei;
3222 struct btrfs_key key;
3227 key.objectid = bytenr;
3228 key.offset = (u64)-1;
3229 key.type = BTRFS_EXTENT_ITEM_KEY;
3231 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
3234 BUG_ON(ret == 0); /* Corruption */
3237 if (path->slots[0] == 0)
3241 leaf = path->nodes[0];
3242 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
3244 if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY)
3248 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
3249 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
3250 if (item_size < sizeof(*ei)) {
3251 WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0));
3255 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
3257 if (item_size != sizeof(*ei) +
3258 btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY))
3261 if (btrfs_extent_generation(leaf, ei) <=
3262 btrfs_root_last_snapshot(&root->root_item))
3265 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
3267 type = btrfs_get_extent_inline_ref_type(leaf, iref, BTRFS_REF_TYPE_DATA);
3268 if (type != BTRFS_EXTENT_DATA_REF_KEY)
3271 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
3272 if (btrfs_extent_refs(leaf, ei) !=
3273 btrfs_extent_data_ref_count(leaf, ref) ||
3274 btrfs_extent_data_ref_root(leaf, ref) !=
3275 root->root_key.objectid ||
3276 btrfs_extent_data_ref_objectid(leaf, ref) != objectid ||
3277 btrfs_extent_data_ref_offset(leaf, ref) != offset)
3285 int btrfs_cross_ref_exist(struct btrfs_root *root, u64 objectid, u64 offset,
3288 struct btrfs_path *path;
3292 path = btrfs_alloc_path();
3297 ret = check_committed_ref(root, path, objectid,
3299 if (ret && ret != -ENOENT)
3302 ret2 = check_delayed_ref(root, path, objectid,
3304 } while (ret2 == -EAGAIN);
3306 if (ret2 && ret2 != -ENOENT) {
3311 if (ret != -ENOENT || ret2 != -ENOENT)
3314 btrfs_free_path(path);
3315 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
3320 static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
3321 struct btrfs_root *root,
3322 struct extent_buffer *buf,
3323 int full_backref, int inc)
3325 struct btrfs_fs_info *fs_info = root->fs_info;
3331 struct btrfs_key key;
3332 struct btrfs_file_extent_item *fi;
3336 int (*process_func)(struct btrfs_trans_handle *,
3337 struct btrfs_root *,
3338 u64, u64, u64, u64, u64, u64);
3341 if (btrfs_is_testing(fs_info))
3344 ref_root = btrfs_header_owner(buf);
3345 nritems = btrfs_header_nritems(buf);
3346 level = btrfs_header_level(buf);
3348 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state) && level == 0)
3352 process_func = btrfs_inc_extent_ref;
3354 process_func = btrfs_free_extent;
3357 parent = buf->start;
3361 for (i = 0; i < nritems; i++) {
3363 btrfs_item_key_to_cpu(buf, &key, i);
3364 if (key.type != BTRFS_EXTENT_DATA_KEY)
3366 fi = btrfs_item_ptr(buf, i,
3367 struct btrfs_file_extent_item);
3368 if (btrfs_file_extent_type(buf, fi) ==
3369 BTRFS_FILE_EXTENT_INLINE)
3371 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
3375 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
3376 key.offset -= btrfs_file_extent_offset(buf, fi);
3377 ret = process_func(trans, root, bytenr, num_bytes,
3378 parent, ref_root, key.objectid,
3383 bytenr = btrfs_node_blockptr(buf, i);
3384 num_bytes = fs_info->nodesize;
3385 ret = process_func(trans, root, bytenr, num_bytes,
3386 parent, ref_root, level - 1, 0);
3396 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
3397 struct extent_buffer *buf, int full_backref)
3399 return __btrfs_mod_ref(trans, root, buf, full_backref, 1);
3402 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
3403 struct extent_buffer *buf, int full_backref)
3405 return __btrfs_mod_ref(trans, root, buf, full_backref, 0);
3408 static int write_one_cache_group(struct btrfs_trans_handle *trans,
3409 struct btrfs_fs_info *fs_info,
3410 struct btrfs_path *path,
3411 struct btrfs_block_group_cache *cache)
3414 struct btrfs_root *extent_root = fs_info->extent_root;
3416 struct extent_buffer *leaf;
3418 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
3425 leaf = path->nodes[0];
3426 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
3427 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
3428 btrfs_mark_buffer_dirty(leaf);
3430 btrfs_release_path(path);
3435 static struct btrfs_block_group_cache *
3436 next_block_group(struct btrfs_fs_info *fs_info,
3437 struct btrfs_block_group_cache *cache)
3439 struct rb_node *node;
3441 spin_lock(&fs_info->block_group_cache_lock);
3443 /* If our block group was removed, we need a full search. */
3444 if (RB_EMPTY_NODE(&cache->cache_node)) {
3445 const u64 next_bytenr = cache->key.objectid + cache->key.offset;
3447 spin_unlock(&fs_info->block_group_cache_lock);
3448 btrfs_put_block_group(cache);
3449 cache = btrfs_lookup_first_block_group(fs_info, next_bytenr); return cache;
3451 node = rb_next(&cache->cache_node);
3452 btrfs_put_block_group(cache);
3454 cache = rb_entry(node, struct btrfs_block_group_cache,
3456 btrfs_get_block_group(cache);
3459 spin_unlock(&fs_info->block_group_cache_lock);
3463 static int cache_save_setup(struct btrfs_block_group_cache *block_group,
3464 struct btrfs_trans_handle *trans,
3465 struct btrfs_path *path)
3467 struct btrfs_fs_info *fs_info = block_group->fs_info;
3468 struct btrfs_root *root = fs_info->tree_root;
3469 struct inode *inode = NULL;
3470 struct extent_changeset *data_reserved = NULL;
3472 int dcs = BTRFS_DC_ERROR;
3478 * If this block group is smaller than 100 megs don't bother caching the
3481 if (block_group->key.offset < (100 * SZ_1M)) {
3482 spin_lock(&block_group->lock);
3483 block_group->disk_cache_state = BTRFS_DC_WRITTEN;
3484 spin_unlock(&block_group->lock);
3491 inode = lookup_free_space_inode(fs_info, block_group, path);
3492 if (IS_ERR(inode) && PTR_ERR(inode) != -ENOENT) {
3493 ret = PTR_ERR(inode);
3494 btrfs_release_path(path);
3498 if (IS_ERR(inode)) {
3502 if (block_group->ro)
3505 ret = create_free_space_inode(fs_info, trans, block_group,
3513 * We want to set the generation to 0, that way if anything goes wrong
3514 * from here on out we know not to trust this cache when we load up next
3517 BTRFS_I(inode)->generation = 0;
3518 ret = btrfs_update_inode(trans, root, inode);
3521 * So theoretically we could recover from this, simply set the
3522 * super cache generation to 0 so we know to invalidate the
3523 * cache, but then we'd have to keep track of the block groups
3524 * that fail this way so we know we _have_ to reset this cache
3525 * before the next commit or risk reading stale cache. So to
3526 * limit our exposure to horrible edge cases lets just abort the
3527 * transaction, this only happens in really bad situations
3530 btrfs_abort_transaction(trans, ret);
3535 /* We've already setup this transaction, go ahead and exit */
3536 if (block_group->cache_generation == trans->transid &&
3537 i_size_read(inode)) {
3538 dcs = BTRFS_DC_SETUP;
3542 if (i_size_read(inode) > 0) {
3543 ret = btrfs_check_trunc_cache_free_space(fs_info,
3544 &fs_info->global_block_rsv);
3548 ret = btrfs_truncate_free_space_cache(trans, NULL, inode);
3553 spin_lock(&block_group->lock);
3554 if (block_group->cached != BTRFS_CACHE_FINISHED ||
3555 !btrfs_test_opt(fs_info, SPACE_CACHE)) {
3557 * don't bother trying to write stuff out _if_
3558 * a) we're not cached,
3559 * b) we're with nospace_cache mount option,
3560 * c) we're with v2 space_cache (FREE_SPACE_TREE).
3562 dcs = BTRFS_DC_WRITTEN;
3563 spin_unlock(&block_group->lock);
3566 spin_unlock(&block_group->lock);
3569 * We hit an ENOSPC when setting up the cache in this transaction, just
3570 * skip doing the setup, we've already cleared the cache so we're safe.
3572 if (test_bit(BTRFS_TRANS_CACHE_ENOSPC, &trans->transaction->flags)) {
3578 * Try to preallocate enough space based on how big the block group is.
3579 * Keep in mind this has to include any pinned space which could end up
3580 * taking up quite a bit since it's not folded into the other space
3583 num_pages = div_u64(block_group->key.offset, SZ_256M);
3588 num_pages *= PAGE_SIZE;
3590 ret = btrfs_check_data_free_space(inode, &data_reserved, 0, num_pages);
3594 ret = btrfs_prealloc_file_range_trans(inode, trans, 0, 0, num_pages,
3595 num_pages, num_pages,
3598 * Our cache requires contiguous chunks so that we don't modify a bunch
3599 * of metadata or split extents when writing the cache out, which means
3600 * we can enospc if we are heavily fragmented in addition to just normal
3601 * out of space conditions. So if we hit this just skip setting up any
3602 * other block groups for this transaction, maybe we'll unpin enough
3603 * space the next time around.
3606 dcs = BTRFS_DC_SETUP;
3607 else if (ret == -ENOSPC)
3608 set_bit(BTRFS_TRANS_CACHE_ENOSPC, &trans->transaction->flags);
3613 btrfs_release_path(path);
3615 spin_lock(&block_group->lock);
3616 if (!ret && dcs == BTRFS_DC_SETUP)
3617 block_group->cache_generation = trans->transid;
3618 block_group->disk_cache_state = dcs;
3619 spin_unlock(&block_group->lock);
3621 extent_changeset_free(data_reserved);
3625 int btrfs_setup_space_cache(struct btrfs_trans_handle *trans,
3626 struct btrfs_fs_info *fs_info)
3628 struct btrfs_block_group_cache *cache, *tmp;
3629 struct btrfs_transaction *cur_trans = trans->transaction;
3630 struct btrfs_path *path;
3632 if (list_empty(&cur_trans->dirty_bgs) ||
3633 !btrfs_test_opt(fs_info, SPACE_CACHE))
3636 path = btrfs_alloc_path();
3640 /* Could add new block groups, use _safe just in case */
3641 list_for_each_entry_safe(cache, tmp, &cur_trans->dirty_bgs,
3643 if (cache->disk_cache_state == BTRFS_DC_CLEAR)
3644 cache_save_setup(cache, trans, path);
3647 btrfs_free_path(path);
3652 * transaction commit does final block group cache writeback during a
3653 * critical section where nothing is allowed to change the FS. This is
3654 * required in order for the cache to actually match the block group,
3655 * but can introduce a lot of latency into the commit.
3657 * So, btrfs_start_dirty_block_groups is here to kick off block group
3658 * cache IO. There's a chance we'll have to redo some of it if the
3659 * block group changes again during the commit, but it greatly reduces
3660 * the commit latency by getting rid of the easy block groups while
3661 * we're still allowing others to join the commit.
3663 int btrfs_start_dirty_block_groups(struct btrfs_trans_handle *trans)
3665 struct btrfs_fs_info *fs_info = trans->fs_info;
3666 struct btrfs_block_group_cache *cache;
3667 struct btrfs_transaction *cur_trans = trans->transaction;
3670 struct btrfs_path *path = NULL;
3672 struct list_head *io = &cur_trans->io_bgs;
3673 int num_started = 0;
3676 spin_lock(&cur_trans->dirty_bgs_lock);
3677 if (list_empty(&cur_trans->dirty_bgs)) {
3678 spin_unlock(&cur_trans->dirty_bgs_lock);
3681 list_splice_init(&cur_trans->dirty_bgs, &dirty);
3682 spin_unlock(&cur_trans->dirty_bgs_lock);
3686 * make sure all the block groups on our dirty list actually
3689 btrfs_create_pending_block_groups(trans);
3692 path = btrfs_alloc_path();
3698 * cache_write_mutex is here only to save us from balance or automatic
3699 * removal of empty block groups deleting this block group while we are
3700 * writing out the cache
3702 mutex_lock(&trans->transaction->cache_write_mutex);
3703 while (!list_empty(&dirty)) {
3704 cache = list_first_entry(&dirty,
3705 struct btrfs_block_group_cache,
3708 * this can happen if something re-dirties a block
3709 * group that is already under IO. Just wait for it to
3710 * finish and then do it all again
3712 if (!list_empty(&cache->io_list)) {
3713 list_del_init(&cache->io_list);
3714 btrfs_wait_cache_io(trans, cache, path);
3715 btrfs_put_block_group(cache);
3720 * btrfs_wait_cache_io uses the cache->dirty_list to decide
3721 * if it should update the cache_state. Don't delete
3722 * until after we wait.
3724 * Since we're not running in the commit critical section
3725 * we need the dirty_bgs_lock to protect from update_block_group
3727 spin_lock(&cur_trans->dirty_bgs_lock);
3728 list_del_init(&cache->dirty_list);
3729 spin_unlock(&cur_trans->dirty_bgs_lock);
3733 cache_save_setup(cache, trans, path);
3735 if (cache->disk_cache_state == BTRFS_DC_SETUP) {
3736 cache->io_ctl.inode = NULL;
3737 ret = btrfs_write_out_cache(fs_info, trans,
3739 if (ret == 0 && cache->io_ctl.inode) {
3744 * The cache_write_mutex is protecting the
3745 * io_list, also refer to the definition of
3746 * btrfs_transaction::io_bgs for more details
3748 list_add_tail(&cache->io_list, io);
3751 * if we failed to write the cache, the
3752 * generation will be bad and life goes on
3758 ret = write_one_cache_group(trans, fs_info,
3761 * Our block group might still be attached to the list
3762 * of new block groups in the transaction handle of some
3763 * other task (struct btrfs_trans_handle->new_bgs). This
3764 * means its block group item isn't yet in the extent
3765 * tree. If this happens ignore the error, as we will
3766 * try again later in the critical section of the
3767 * transaction commit.
3769 if (ret == -ENOENT) {
3771 spin_lock(&cur_trans->dirty_bgs_lock);
3772 if (list_empty(&cache->dirty_list)) {
3773 list_add_tail(&cache->dirty_list,
3774 &cur_trans->dirty_bgs);
3775 btrfs_get_block_group(cache);
3777 spin_unlock(&cur_trans->dirty_bgs_lock);
3779 btrfs_abort_transaction(trans, ret);
3783 /* if its not on the io list, we need to put the block group */
3785 btrfs_put_block_group(cache);
3791 * Avoid blocking other tasks for too long. It might even save
3792 * us from writing caches for block groups that are going to be
3795 mutex_unlock(&trans->transaction->cache_write_mutex);
3796 mutex_lock(&trans->transaction->cache_write_mutex);
3798 mutex_unlock(&trans->transaction->cache_write_mutex);
3801 * go through delayed refs for all the stuff we've just kicked off
3802 * and then loop back (just once)
3804 ret = btrfs_run_delayed_refs(trans, 0);
3805 if (!ret && loops == 0) {
3807 spin_lock(&cur_trans->dirty_bgs_lock);
3808 list_splice_init(&cur_trans->dirty_bgs, &dirty);
3810 * dirty_bgs_lock protects us from concurrent block group
3811 * deletes too (not just cache_write_mutex).
3813 if (!list_empty(&dirty)) {
3814 spin_unlock(&cur_trans->dirty_bgs_lock);
3817 spin_unlock(&cur_trans->dirty_bgs_lock);
3818 } else if (ret < 0) {
3819 btrfs_cleanup_dirty_bgs(cur_trans, fs_info);
3822 btrfs_free_path(path);
3826 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
3827 struct btrfs_fs_info *fs_info)
3829 struct btrfs_block_group_cache *cache;
3830 struct btrfs_transaction *cur_trans = trans->transaction;
3833 struct btrfs_path *path;
3834 struct list_head *io = &cur_trans->io_bgs;
3835 int num_started = 0;
3837 path = btrfs_alloc_path();
3842 * Even though we are in the critical section of the transaction commit,
3843 * we can still have concurrent tasks adding elements to this
3844 * transaction's list of dirty block groups. These tasks correspond to
3845 * endio free space workers started when writeback finishes for a
3846 * space cache, which run inode.c:btrfs_finish_ordered_io(), and can
3847 * allocate new block groups as a result of COWing nodes of the root
3848 * tree when updating the free space inode. The writeback for the space
3849 * caches is triggered by an earlier call to
3850 * btrfs_start_dirty_block_groups() and iterations of the following
3852 * Also we want to do the cache_save_setup first and then run the
3853 * delayed refs to make sure we have the best chance at doing this all
3856 spin_lock(&cur_trans->dirty_bgs_lock);
3857 while (!list_empty(&cur_trans->dirty_bgs)) {
3858 cache = list_first_entry(&cur_trans->dirty_bgs,
3859 struct btrfs_block_group_cache,
3863 * this can happen if cache_save_setup re-dirties a block
3864 * group that is already under IO. Just wait for it to
3865 * finish and then do it all again
3867 if (!list_empty(&cache->io_list)) {
3868 spin_unlock(&cur_trans->dirty_bgs_lock);
3869 list_del_init(&cache->io_list);
3870 btrfs_wait_cache_io(trans, cache, path);
3871 btrfs_put_block_group(cache);
3872 spin_lock(&cur_trans->dirty_bgs_lock);
3876 * don't remove from the dirty list until after we've waited
3879 list_del_init(&cache->dirty_list);
3880 spin_unlock(&cur_trans->dirty_bgs_lock);
3883 cache_save_setup(cache, trans, path);
3886 ret = btrfs_run_delayed_refs(trans,
3887 (unsigned long) -1);
3889 if (!ret && cache->disk_cache_state == BTRFS_DC_SETUP) {
3890 cache->io_ctl.inode = NULL;
3891 ret = btrfs_write_out_cache(fs_info, trans,
3893 if (ret == 0 && cache->io_ctl.inode) {
3896 list_add_tail(&cache->io_list, io);
3899 * if we failed to write the cache, the
3900 * generation will be bad and life goes on
3906 ret = write_one_cache_group(trans, fs_info,
3909 * One of the free space endio workers might have
3910 * created a new block group while updating a free space
3911 * cache's inode (at inode.c:btrfs_finish_ordered_io())
3912 * and hasn't released its transaction handle yet, in
3913 * which case the new block group is still attached to
3914 * its transaction handle and its creation has not
3915 * finished yet (no block group item in the extent tree
3916 * yet, etc). If this is the case, wait for all free
3917 * space endio workers to finish and retry. This is a
3918 * a very rare case so no need for a more efficient and
3921 if (ret == -ENOENT) {
3922 wait_event(cur_trans->writer_wait,
3923 atomic_read(&cur_trans->num_writers) == 1);
3924 ret = write_one_cache_group(trans, fs_info,
3928 btrfs_abort_transaction(trans, ret);
3931 /* if its not on the io list, we need to put the block group */
3933 btrfs_put_block_group(cache);
3934 spin_lock(&cur_trans->dirty_bgs_lock);
3936 spin_unlock(&cur_trans->dirty_bgs_lock);
3939 * Refer to the definition of io_bgs member for details why it's safe
3940 * to use it without any locking
3942 while (!list_empty(io)) {
3943 cache = list_first_entry(io, struct btrfs_block_group_cache,
3945 list_del_init(&cache->io_list);
3946 btrfs_wait_cache_io(trans, cache, path);
3947 btrfs_put_block_group(cache);
3950 btrfs_free_path(path);
3954 int btrfs_extent_readonly(struct btrfs_fs_info *fs_info, u64 bytenr)
3956 struct btrfs_block_group_cache *block_group;
3959 block_group = btrfs_lookup_block_group(fs_info, bytenr);
3960 if (!block_group || block_group->ro)
3963 btrfs_put_block_group(block_group);
3967 bool btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr)
3969 struct btrfs_block_group_cache *bg;
3972 bg = btrfs_lookup_block_group(fs_info, bytenr);
3976 spin_lock(&bg->lock);
3980 atomic_inc(&bg->nocow_writers);
3981 spin_unlock(&bg->lock);
3983 /* no put on block group, done by btrfs_dec_nocow_writers */
3985 btrfs_put_block_group(bg);
3991 void btrfs_dec_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr)
3993 struct btrfs_block_group_cache *bg;
3995 bg = btrfs_lookup_block_group(fs_info, bytenr);
3997 if (atomic_dec_and_test(&bg->nocow_writers))
3998 wake_up_var(&bg->nocow_writers);
4000 * Once for our lookup and once for the lookup done by a previous call
4001 * to btrfs_inc_nocow_writers()
4003 btrfs_put_block_group(bg);
4004 btrfs_put_block_group(bg);
4007 void btrfs_wait_nocow_writers(struct btrfs_block_group_cache *bg)
4009 wait_var_event(&bg->nocow_writers, !atomic_read(&bg->nocow_writers));
4012 static const char *alloc_name(u64 flags)
4015 case BTRFS_BLOCK_GROUP_METADATA|BTRFS_BLOCK_GROUP_DATA:
4017 case BTRFS_BLOCK_GROUP_METADATA:
4019 case BTRFS_BLOCK_GROUP_DATA:
4021 case BTRFS_BLOCK_GROUP_SYSTEM:
4025 return "invalid-combination";
4029 static int create_space_info(struct btrfs_fs_info *info, u64 flags,
4030 struct btrfs_space_info **new)
4033 struct btrfs_space_info *space_info;
4037 space_info = kzalloc(sizeof(*space_info), GFP_NOFS);
4041 ret = percpu_counter_init(&space_info->total_bytes_pinned, 0,
4048 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
4049 INIT_LIST_HEAD(&space_info->block_groups[i]);
4050 init_rwsem(&space_info->groups_sem);
4051 spin_lock_init(&space_info->lock);
4052 space_info->flags = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
4053 space_info->force_alloc = CHUNK_ALLOC_NO_FORCE;
4054 init_waitqueue_head(&space_info->wait);
4055 INIT_LIST_HEAD(&space_info->ro_bgs);
4056 INIT_LIST_HEAD(&space_info->tickets);
4057 INIT_LIST_HEAD(&space_info->priority_tickets);
4059 ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype,
4060 info->space_info_kobj, "%s",
4061 alloc_name(space_info->flags));
4063 percpu_counter_destroy(&space_info->total_bytes_pinned);
4069 list_add_rcu(&space_info->list, &info->space_info);
4070 if (flags & BTRFS_BLOCK_GROUP_DATA)
4071 info->data_sinfo = space_info;
4076 static void update_space_info(struct btrfs_fs_info *info, u64 flags,
4077 u64 total_bytes, u64 bytes_used,
4079 struct btrfs_space_info **space_info)
4081 struct btrfs_space_info *found;
4084 if (flags & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
4085 BTRFS_BLOCK_GROUP_RAID10))
4090 found = __find_space_info(info, flags);
4092 spin_lock(&found->lock);
4093 found->total_bytes += total_bytes;
4094 found->disk_total += total_bytes * factor;
4095 found->bytes_used += bytes_used;
4096 found->disk_used += bytes_used * factor;
4097 found->bytes_readonly += bytes_readonly;
4098 if (total_bytes > 0)
4100 space_info_add_new_bytes(info, found, total_bytes -
4101 bytes_used - bytes_readonly);
4102 spin_unlock(&found->lock);
4103 *space_info = found;
4106 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
4108 u64 extra_flags = chunk_to_extended(flags) &
4109 BTRFS_EXTENDED_PROFILE_MASK;
4111 write_seqlock(&fs_info->profiles_lock);
4112 if (flags & BTRFS_BLOCK_GROUP_DATA)
4113 fs_info->avail_data_alloc_bits |= extra_flags;
4114 if (flags & BTRFS_BLOCK_GROUP_METADATA)
4115 fs_info->avail_metadata_alloc_bits |= extra_flags;
4116 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
4117 fs_info->avail_system_alloc_bits |= extra_flags;
4118 write_sequnlock(&fs_info->profiles_lock);
4122 * returns target flags in extended format or 0 if restripe for this
4123 * chunk_type is not in progress
4125 * should be called with either volume_mutex or balance_lock held
4127 static u64 get_restripe_target(struct btrfs_fs_info *fs_info, u64 flags)
4129 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4135 if (flags & BTRFS_BLOCK_GROUP_DATA &&
4136 bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) {
4137 target = BTRFS_BLOCK_GROUP_DATA | bctl->data.target;
4138 } else if (flags & BTRFS_BLOCK_GROUP_SYSTEM &&
4139 bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
4140 target = BTRFS_BLOCK_GROUP_SYSTEM | bctl->sys.target;
4141 } else if (flags & BTRFS_BLOCK_GROUP_METADATA &&
4142 bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) {
4143 target = BTRFS_BLOCK_GROUP_METADATA | bctl->meta.target;
4150 * @flags: available profiles in extended format (see ctree.h)
4152 * Returns reduced profile in chunk format. If profile changing is in
4153 * progress (either running or paused) picks the target profile (if it's
4154 * already available), otherwise falls back to plain reducing.
4156 static u64 btrfs_reduce_alloc_profile(struct btrfs_fs_info *fs_info, u64 flags)
4158 u64 num_devices = fs_info->fs_devices->rw_devices;
4164 * see if restripe for this chunk_type is in progress, if so
4165 * try to reduce to the target profile
4167 spin_lock(&fs_info->balance_lock);
4168 target = get_restripe_target(fs_info, flags);
4170 /* pick target profile only if it's already available */
4171 if ((flags & target) & BTRFS_EXTENDED_PROFILE_MASK) {
4172 spin_unlock(&fs_info->balance_lock);
4173 return extended_to_chunk(target);
4176 spin_unlock(&fs_info->balance_lock);
4178 /* First, mask out the RAID levels which aren't possible */
4179 for (raid_type = 0; raid_type < BTRFS_NR_RAID_TYPES; raid_type++) {
4180 if (num_devices >= btrfs_raid_array[raid_type].devs_min)
4181 allowed |= btrfs_raid_group[raid_type];
4185 if (allowed & BTRFS_BLOCK_GROUP_RAID6)
4186 allowed = BTRFS_BLOCK_GROUP_RAID6;
4187 else if (allowed & BTRFS_BLOCK_GROUP_RAID5)
4188 allowed = BTRFS_BLOCK_GROUP_RAID5;
4189 else if (allowed & BTRFS_BLOCK_GROUP_RAID10)
4190 allowed = BTRFS_BLOCK_GROUP_RAID10;
4191 else if (allowed & BTRFS_BLOCK_GROUP_RAID1)
4192 allowed = BTRFS_BLOCK_GROUP_RAID1;
4193 else if (allowed & BTRFS_BLOCK_GROUP_RAID0)
4194 allowed = BTRFS_BLOCK_GROUP_RAID0;
4196 flags &= ~BTRFS_BLOCK_GROUP_PROFILE_MASK;
4198 return extended_to_chunk(flags | allowed);
4201 static u64 get_alloc_profile(struct btrfs_fs_info *fs_info, u64 orig_flags)
4208 seq = read_seqbegin(&fs_info->profiles_lock);
4210 if (flags & BTRFS_BLOCK_GROUP_DATA)
4211 flags |= fs_info->avail_data_alloc_bits;
4212 else if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
4213 flags |= fs_info->avail_system_alloc_bits;
4214 else if (flags & BTRFS_BLOCK_GROUP_METADATA)
4215 flags |= fs_info->avail_metadata_alloc_bits;
4216 } while (read_seqretry(&fs_info->profiles_lock, seq));
4218 return btrfs_reduce_alloc_profile(fs_info, flags);
4221 static u64 get_alloc_profile_by_root(struct btrfs_root *root, int data)
4223 struct btrfs_fs_info *fs_info = root->fs_info;
4228 flags = BTRFS_BLOCK_GROUP_DATA;
4229 else if (root == fs_info->chunk_root)
4230 flags = BTRFS_BLOCK_GROUP_SYSTEM;
4232 flags = BTRFS_BLOCK_GROUP_METADATA;
4234 ret = get_alloc_profile(fs_info, flags);
4238 u64 btrfs_data_alloc_profile(struct btrfs_fs_info *fs_info)
4240 return get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_DATA);
4243 u64 btrfs_metadata_alloc_profile(struct btrfs_fs_info *fs_info)
4245 return get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_METADATA);
4248 u64 btrfs_system_alloc_profile(struct btrfs_fs_info *fs_info)
4250 return get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
4253 static u64 btrfs_space_info_used(struct btrfs_space_info *s_info,
4254 bool may_use_included)
4257 return s_info->bytes_used + s_info->bytes_reserved +
4258 s_info->bytes_pinned + s_info->bytes_readonly +
4259 (may_use_included ? s_info->bytes_may_use : 0);
4262 int btrfs_alloc_data_chunk_ondemand(struct btrfs_inode *inode, u64 bytes)
4264 struct btrfs_root *root = inode->root;
4265 struct btrfs_fs_info *fs_info = root->fs_info;
4266 struct btrfs_space_info *data_sinfo = fs_info->data_sinfo;
4269 int need_commit = 2;
4270 int have_pinned_space;
4272 /* make sure bytes are sectorsize aligned */
4273 bytes = ALIGN(bytes, fs_info->sectorsize);
4275 if (btrfs_is_free_space_inode(inode)) {
4277 ASSERT(current->journal_info);
4281 /* make sure we have enough space to handle the data first */
4282 spin_lock(&data_sinfo->lock);
4283 used = btrfs_space_info_used(data_sinfo, true);
4285 if (used + bytes > data_sinfo->total_bytes) {
4286 struct btrfs_trans_handle *trans;
4289 * if we don't have enough free bytes in this space then we need
4290 * to alloc a new chunk.
4292 if (!data_sinfo->full) {
4295 data_sinfo->force_alloc = CHUNK_ALLOC_FORCE;
4296 spin_unlock(&data_sinfo->lock);
4298 alloc_target = btrfs_data_alloc_profile(fs_info);
4300 * It is ugly that we don't call nolock join
4301 * transaction for the free space inode case here.
4302 * But it is safe because we only do the data space
4303 * reservation for the free space cache in the
4304 * transaction context, the common join transaction
4305 * just increase the counter of the current transaction
4306 * handler, doesn't try to acquire the trans_lock of
4309 trans = btrfs_join_transaction(root);
4311 return PTR_ERR(trans);
4313 ret = do_chunk_alloc(trans, fs_info, alloc_target,
4314 CHUNK_ALLOC_NO_FORCE);
4315 btrfs_end_transaction(trans);
4320 have_pinned_space = 1;
4329 * If we don't have enough pinned space to deal with this
4330 * allocation, and no removed chunk in current transaction,
4331 * don't bother committing the transaction.
4333 have_pinned_space = percpu_counter_compare(
4334 &data_sinfo->total_bytes_pinned,
4335 used + bytes - data_sinfo->total_bytes);
4336 spin_unlock(&data_sinfo->lock);
4338 /* commit the current transaction and try again */
4343 if (need_commit > 0) {
4344 btrfs_start_delalloc_roots(fs_info, 0, -1);
4345 btrfs_wait_ordered_roots(fs_info, U64_MAX, 0,
4349 trans = btrfs_join_transaction(root);
4351 return PTR_ERR(trans);
4352 if (have_pinned_space >= 0 ||
4353 test_bit(BTRFS_TRANS_HAVE_FREE_BGS,
4354 &trans->transaction->flags) ||
4356 ret = btrfs_commit_transaction(trans);
4360 * The cleaner kthread might still be doing iput
4361 * operations. Wait for it to finish so that
4362 * more space is released.
4364 mutex_lock(&fs_info->cleaner_delayed_iput_mutex);
4365 mutex_unlock(&fs_info->cleaner_delayed_iput_mutex);
4368 btrfs_end_transaction(trans);
4372 trace_btrfs_space_reservation(fs_info,
4373 "space_info:enospc",
4374 data_sinfo->flags, bytes, 1);
4377 data_sinfo->bytes_may_use += bytes;
4378 trace_btrfs_space_reservation(fs_info, "space_info",
4379 data_sinfo->flags, bytes, 1);
4380 spin_unlock(&data_sinfo->lock);
4385 int btrfs_check_data_free_space(struct inode *inode,
4386 struct extent_changeset **reserved, u64 start, u64 len)
4388 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4391 /* align the range */
4392 len = round_up(start + len, fs_info->sectorsize) -
4393 round_down(start, fs_info->sectorsize);
4394 start = round_down(start, fs_info->sectorsize);
4396 ret = btrfs_alloc_data_chunk_ondemand(BTRFS_I(inode), len);
4400 /* Use new btrfs_qgroup_reserve_data to reserve precious data space. */
4401 ret = btrfs_qgroup_reserve_data(inode, reserved, start, len);
4403 btrfs_free_reserved_data_space_noquota(inode, start, len);
4410 * Called if we need to clear a data reservation for this inode
4411 * Normally in a error case.
4413 * This one will *NOT* use accurate qgroup reserved space API, just for case
4414 * which we can't sleep and is sure it won't affect qgroup reserved space.
4415 * Like clear_bit_hook().
4417 void btrfs_free_reserved_data_space_noquota(struct inode *inode, u64 start,
4420 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4421 struct btrfs_space_info *data_sinfo;
4423 /* Make sure the range is aligned to sectorsize */
4424 len = round_up(start + len, fs_info->sectorsize) -
4425 round_down(start, fs_info->sectorsize);
4426 start = round_down(start, fs_info->sectorsize);
4428 data_sinfo = fs_info->data_sinfo;
4429 spin_lock(&data_sinfo->lock);
4430 if (WARN_ON(data_sinfo->bytes_may_use < len))
4431 data_sinfo->bytes_may_use = 0;
4433 data_sinfo->bytes_may_use -= len;
4434 trace_btrfs_space_reservation(fs_info, "space_info",
4435 data_sinfo->flags, len, 0);
4436 spin_unlock(&data_sinfo->lock);
4440 * Called if we need to clear a data reservation for this inode
4441 * Normally in a error case.
4443 * This one will handle the per-inode data rsv map for accurate reserved
4446 void btrfs_free_reserved_data_space(struct inode *inode,
4447 struct extent_changeset *reserved, u64 start, u64 len)
4449 struct btrfs_root *root = BTRFS_I(inode)->root;
4451 /* Make sure the range is aligned to sectorsize */
4452 len = round_up(start + len, root->fs_info->sectorsize) -
4453 round_down(start, root->fs_info->sectorsize);
4454 start = round_down(start, root->fs_info->sectorsize);
4456 btrfs_free_reserved_data_space_noquota(inode, start, len);
4457 btrfs_qgroup_free_data(inode, reserved, start, len);
4460 static void force_metadata_allocation(struct btrfs_fs_info *info)
4462 struct list_head *head = &info->space_info;
4463 struct btrfs_space_info *found;
4466 list_for_each_entry_rcu(found, head, list) {
4467 if (found->flags & BTRFS_BLOCK_GROUP_METADATA)
4468 found->force_alloc = CHUNK_ALLOC_FORCE;
4473 static inline u64 calc_global_rsv_need_space(struct btrfs_block_rsv *global)
4475 return (global->size << 1);
4478 static int should_alloc_chunk(struct btrfs_fs_info *fs_info,
4479 struct btrfs_space_info *sinfo, int force)
4481 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
4482 u64 bytes_used = btrfs_space_info_used(sinfo, false);
4485 if (force == CHUNK_ALLOC_FORCE)
4489 * We need to take into account the global rsv because for all intents
4490 * and purposes it's used space. Don't worry about locking the
4491 * global_rsv, it doesn't change except when the transaction commits.
4493 if (sinfo->flags & BTRFS_BLOCK_GROUP_METADATA)
4494 bytes_used += calc_global_rsv_need_space(global_rsv);
4497 * in limited mode, we want to have some free space up to
4498 * about 1% of the FS size.
4500 if (force == CHUNK_ALLOC_LIMITED) {
4501 thresh = btrfs_super_total_bytes(fs_info->super_copy);
4502 thresh = max_t(u64, SZ_64M, div_factor_fine(thresh, 1));
4504 if (sinfo->total_bytes - bytes_used < thresh)
4508 if (bytes_used + SZ_2M < div_factor(sinfo->total_bytes, 8))
4513 static u64 get_profile_num_devs(struct btrfs_fs_info *fs_info, u64 type)
4517 if (type & (BTRFS_BLOCK_GROUP_RAID10 |
4518 BTRFS_BLOCK_GROUP_RAID0 |
4519 BTRFS_BLOCK_GROUP_RAID5 |
4520 BTRFS_BLOCK_GROUP_RAID6))
4521 num_dev = fs_info->fs_devices->rw_devices;
4522 else if (type & BTRFS_BLOCK_GROUP_RAID1)
4525 num_dev = 1; /* DUP or single */
4531 * If @is_allocation is true, reserve space in the system space info necessary
4532 * for allocating a chunk, otherwise if it's false, reserve space necessary for
4535 void check_system_chunk(struct btrfs_trans_handle *trans,
4536 struct btrfs_fs_info *fs_info, u64 type)
4538 struct btrfs_space_info *info;
4545 * Needed because we can end up allocating a system chunk and for an
4546 * atomic and race free space reservation in the chunk block reserve.
4548 lockdep_assert_held(&fs_info->chunk_mutex);
4550 info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
4551 spin_lock(&info->lock);
4552 left = info->total_bytes - btrfs_space_info_used(info, true);
4553 spin_unlock(&info->lock);
4555 num_devs = get_profile_num_devs(fs_info, type);
4557 /* num_devs device items to update and 1 chunk item to add or remove */
4558 thresh = btrfs_calc_trunc_metadata_size(fs_info, num_devs) +
4559 btrfs_calc_trans_metadata_size(fs_info, 1);
4561 if (left < thresh && btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
4562 btrfs_info(fs_info, "left=%llu, need=%llu, flags=%llu",
4563 left, thresh, type);
4564 dump_space_info(fs_info, info, 0, 0);
4567 if (left < thresh) {
4568 u64 flags = btrfs_system_alloc_profile(fs_info);
4571 * Ignore failure to create system chunk. We might end up not
4572 * needing it, as we might not need to COW all nodes/leafs from
4573 * the paths we visit in the chunk tree (they were already COWed
4574 * or created in the current transaction for example).
4576 ret = btrfs_alloc_chunk(trans, fs_info, flags);
4580 ret = btrfs_block_rsv_add(fs_info->chunk_root,
4581 &fs_info->chunk_block_rsv,
4582 thresh, BTRFS_RESERVE_NO_FLUSH);
4584 trans->chunk_bytes_reserved += thresh;
4589 * If force is CHUNK_ALLOC_FORCE:
4590 * - return 1 if it successfully allocates a chunk,
4591 * - return errors including -ENOSPC otherwise.
4592 * If force is NOT CHUNK_ALLOC_FORCE:
4593 * - return 0 if it doesn't need to allocate a new chunk,
4594 * - return 1 if it successfully allocates a chunk,
4595 * - return errors including -ENOSPC otherwise.
4597 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
4598 struct btrfs_fs_info *fs_info, u64 flags, int force)
4600 struct btrfs_space_info *space_info;
4601 int wait_for_alloc = 0;
4604 /* Don't re-enter if we're already allocating a chunk */
4605 if (trans->allocating_chunk)
4608 space_info = __find_space_info(fs_info, flags);
4612 spin_lock(&space_info->lock);
4613 if (force < space_info->force_alloc)
4614 force = space_info->force_alloc;
4615 if (space_info->full) {
4616 if (should_alloc_chunk(fs_info, space_info, force))
4620 spin_unlock(&space_info->lock);
4624 if (!should_alloc_chunk(fs_info, space_info, force)) {
4625 spin_unlock(&space_info->lock);
4627 } else if (space_info->chunk_alloc) {
4630 space_info->chunk_alloc = 1;
4633 spin_unlock(&space_info->lock);
4635 mutex_lock(&fs_info->chunk_mutex);
4638 * The chunk_mutex is held throughout the entirety of a chunk
4639 * allocation, so once we've acquired the chunk_mutex we know that the
4640 * other guy is done and we need to recheck and see if we should
4643 if (wait_for_alloc) {
4644 mutex_unlock(&fs_info->chunk_mutex);
4650 trans->allocating_chunk = true;
4653 * If we have mixed data/metadata chunks we want to make sure we keep
4654 * allocating mixed chunks instead of individual chunks.
4656 if (btrfs_mixed_space_info(space_info))
4657 flags |= (BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA);
4660 * if we're doing a data chunk, go ahead and make sure that
4661 * we keep a reasonable number of metadata chunks allocated in the
4664 if (flags & BTRFS_BLOCK_GROUP_DATA && fs_info->metadata_ratio) {
4665 fs_info->data_chunk_allocations++;
4666 if (!(fs_info->data_chunk_allocations %
4667 fs_info->metadata_ratio))
4668 force_metadata_allocation(fs_info);
4672 * Check if we have enough space in SYSTEM chunk because we may need
4673 * to update devices.
4675 check_system_chunk(trans, fs_info, flags);
4677 ret = btrfs_alloc_chunk(trans, fs_info, flags);
4678 trans->allocating_chunk = false;
4680 spin_lock(&space_info->lock);
4681 if (ret < 0 && ret != -ENOSPC)
4684 space_info->full = 1;
4688 space_info->force_alloc = CHUNK_ALLOC_NO_FORCE;
4690 space_info->chunk_alloc = 0;
4691 spin_unlock(&space_info->lock);
4692 mutex_unlock(&fs_info->chunk_mutex);
4694 * When we allocate a new chunk we reserve space in the chunk block
4695 * reserve to make sure we can COW nodes/leafs in the chunk tree or
4696 * add new nodes/leafs to it if we end up needing to do it when
4697 * inserting the chunk item and updating device items as part of the
4698 * second phase of chunk allocation, performed by
4699 * btrfs_finish_chunk_alloc(). So make sure we don't accumulate a
4700 * large number of new block groups to create in our transaction
4701 * handle's new_bgs list to avoid exhausting the chunk block reserve
4702 * in extreme cases - like having a single transaction create many new
4703 * block groups when starting to write out the free space caches of all
4704 * the block groups that were made dirty during the lifetime of the
4707 if (trans->can_flush_pending_bgs &&
4708 trans->chunk_bytes_reserved >= (u64)SZ_2M) {
4709 btrfs_create_pending_block_groups(trans);
4710 btrfs_trans_release_chunk_metadata(trans);
4715 static int can_overcommit(struct btrfs_fs_info *fs_info,
4716 struct btrfs_space_info *space_info, u64 bytes,
4717 enum btrfs_reserve_flush_enum flush,
4720 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
4726 /* Don't overcommit when in mixed mode. */
4727 if (space_info->flags & BTRFS_BLOCK_GROUP_DATA)
4731 profile = btrfs_system_alloc_profile(fs_info);
4733 profile = btrfs_metadata_alloc_profile(fs_info);
4735 used = btrfs_space_info_used(space_info, false);
4738 * We only want to allow over committing if we have lots of actual space
4739 * free, but if we don't have enough space to handle the global reserve
4740 * space then we could end up having a real enospc problem when trying
4741 * to allocate a chunk or some other such important allocation.
4743 spin_lock(&global_rsv->lock);
4744 space_size = calc_global_rsv_need_space(global_rsv);
4745 spin_unlock(&global_rsv->lock);
4746 if (used + space_size >= space_info->total_bytes)
4749 used += space_info->bytes_may_use;
4751 avail = atomic64_read(&fs_info->free_chunk_space);
4754 * If we have dup, raid1 or raid10 then only half of the free
4755 * space is actually useable. For raid56, the space info used
4756 * doesn't include the parity drive, so we don't have to
4759 if (profile & (BTRFS_BLOCK_GROUP_DUP |
4760 BTRFS_BLOCK_GROUP_RAID1 |
4761 BTRFS_BLOCK_GROUP_RAID10))
4765 * If we aren't flushing all things, let us overcommit up to
4766 * 1/2th of the space. If we can flush, don't let us overcommit
4767 * too much, let it overcommit up to 1/8 of the space.
4769 if (flush == BTRFS_RESERVE_FLUSH_ALL)
4774 if (used + bytes < space_info->total_bytes + avail)
4779 static void btrfs_writeback_inodes_sb_nr(struct btrfs_fs_info *fs_info,
4780 unsigned long nr_pages, int nr_items)
4782 struct super_block *sb = fs_info->sb;
4784 if (down_read_trylock(&sb->s_umount)) {
4785 writeback_inodes_sb_nr(sb, nr_pages, WB_REASON_FS_FREE_SPACE);
4786 up_read(&sb->s_umount);
4789 * We needn't worry the filesystem going from r/w to r/o though
4790 * we don't acquire ->s_umount mutex, because the filesystem
4791 * should guarantee the delalloc inodes list be empty after
4792 * the filesystem is readonly(all dirty pages are written to
4795 btrfs_start_delalloc_roots(fs_info, 0, nr_items);
4796 if (!current->journal_info)
4797 btrfs_wait_ordered_roots(fs_info, nr_items, 0, (u64)-1);
4801 static inline u64 calc_reclaim_items_nr(struct btrfs_fs_info *fs_info,
4807 bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
4808 nr = div64_u64(to_reclaim, bytes);
4814 #define EXTENT_SIZE_PER_ITEM SZ_256K
4817 * shrink metadata reservation for delalloc
4819 static void shrink_delalloc(struct btrfs_fs_info *fs_info, u64 to_reclaim,
4820 u64 orig, bool wait_ordered)
4822 struct btrfs_space_info *space_info;
4823 struct btrfs_trans_handle *trans;
4828 unsigned long nr_pages;
4831 /* Calc the number of the pages we need flush for space reservation */
4832 items = calc_reclaim_items_nr(fs_info, to_reclaim);
4833 to_reclaim = items * EXTENT_SIZE_PER_ITEM;
4835 trans = (struct btrfs_trans_handle *)current->journal_info;
4836 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
4838 delalloc_bytes = percpu_counter_sum_positive(
4839 &fs_info->delalloc_bytes);
4840 if (delalloc_bytes == 0) {
4844 btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1);
4849 while (delalloc_bytes && loops < 3) {
4850 max_reclaim = min(delalloc_bytes, to_reclaim);
4851 nr_pages = max_reclaim >> PAGE_SHIFT;
4852 btrfs_writeback_inodes_sb_nr(fs_info, nr_pages, items);
4854 * We need to wait for the async pages to actually start before
4857 max_reclaim = atomic_read(&fs_info->async_delalloc_pages);
4861 if (max_reclaim <= nr_pages)
4864 max_reclaim -= nr_pages;
4866 wait_event(fs_info->async_submit_wait,
4867 atomic_read(&fs_info->async_delalloc_pages) <=
4870 spin_lock(&space_info->lock);
4871 if (list_empty(&space_info->tickets) &&
4872 list_empty(&space_info->priority_tickets)) {
4873 spin_unlock(&space_info->lock);
4876 spin_unlock(&space_info->lock);
4879 if (wait_ordered && !trans) {
4880 btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1);
4882 time_left = schedule_timeout_killable(1);
4886 delalloc_bytes = percpu_counter_sum_positive(
4887 &fs_info->delalloc_bytes);
4891 struct reserve_ticket {
4894 struct list_head list;
4895 wait_queue_head_t wait;
4899 * maybe_commit_transaction - possibly commit the transaction if its ok to
4900 * @root - the root we're allocating for
4901 * @bytes - the number of bytes we want to reserve
4902 * @force - force the commit
4904 * This will check to make sure that committing the transaction will actually
4905 * get us somewhere and then commit the transaction if it does. Otherwise it
4906 * will return -ENOSPC.
4908 static int may_commit_transaction(struct btrfs_fs_info *fs_info,
4909 struct btrfs_space_info *space_info)
4911 struct reserve_ticket *ticket = NULL;
4912 struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_block_rsv;
4913 struct btrfs_trans_handle *trans;
4916 trans = (struct btrfs_trans_handle *)current->journal_info;
4920 spin_lock(&space_info->lock);
4921 if (!list_empty(&space_info->priority_tickets))
4922 ticket = list_first_entry(&space_info->priority_tickets,
4923 struct reserve_ticket, list);
4924 else if (!list_empty(&space_info->tickets))
4925 ticket = list_first_entry(&space_info->tickets,
4926 struct reserve_ticket, list);
4927 bytes = (ticket) ? ticket->bytes : 0;
4928 spin_unlock(&space_info->lock);
4933 /* See if there is enough pinned space to make this reservation */
4934 if (percpu_counter_compare(&space_info->total_bytes_pinned,
4939 * See if there is some space in the delayed insertion reservation for
4942 if (space_info != delayed_rsv->space_info)
4945 spin_lock(&delayed_rsv->lock);
4946 if (delayed_rsv->size > bytes)
4949 bytes -= delayed_rsv->size;
4950 spin_unlock(&delayed_rsv->lock);
4952 if (percpu_counter_compare(&space_info->total_bytes_pinned,
4958 trans = btrfs_join_transaction(fs_info->extent_root);
4962 return btrfs_commit_transaction(trans);
4966 * Try to flush some data based on policy set by @state. This is only advisory
4967 * and may fail for various reasons. The caller is supposed to examine the
4968 * state of @space_info to detect the outcome.
4970 static void flush_space(struct btrfs_fs_info *fs_info,
4971 struct btrfs_space_info *space_info, u64 num_bytes,
4974 struct btrfs_root *root = fs_info->extent_root;
4975 struct btrfs_trans_handle *trans;
4980 case FLUSH_DELAYED_ITEMS_NR:
4981 case FLUSH_DELAYED_ITEMS:
4982 if (state == FLUSH_DELAYED_ITEMS_NR)
4983 nr = calc_reclaim_items_nr(fs_info, num_bytes) * 2;
4987 trans = btrfs_join_transaction(root);
4988 if (IS_ERR(trans)) {
4989 ret = PTR_ERR(trans);
4992 ret = btrfs_run_delayed_items_nr(trans, nr);
4993 btrfs_end_transaction(trans);
4995 case FLUSH_DELALLOC:
4996 case FLUSH_DELALLOC_WAIT:
4997 shrink_delalloc(fs_info, num_bytes * 2, num_bytes,
4998 state == FLUSH_DELALLOC_WAIT);
5001 trans = btrfs_join_transaction(root);
5002 if (IS_ERR(trans)) {
5003 ret = PTR_ERR(trans);
5006 ret = do_chunk_alloc(trans, fs_info,
5007 btrfs_metadata_alloc_profile(fs_info),
5008 CHUNK_ALLOC_NO_FORCE);
5009 btrfs_end_transaction(trans);
5010 if (ret > 0 || ret == -ENOSPC)
5014 ret = may_commit_transaction(fs_info, space_info);
5021 trace_btrfs_flush_space(fs_info, space_info->flags, num_bytes, state,
5027 btrfs_calc_reclaim_metadata_size(struct btrfs_fs_info *fs_info,
5028 struct btrfs_space_info *space_info,
5031 struct reserve_ticket *ticket;
5036 list_for_each_entry(ticket, &space_info->tickets, list)
5037 to_reclaim += ticket->bytes;
5038 list_for_each_entry(ticket, &space_info->priority_tickets, list)
5039 to_reclaim += ticket->bytes;
5043 to_reclaim = min_t(u64, num_online_cpus() * SZ_1M, SZ_16M);
5044 if (can_overcommit(fs_info, space_info, to_reclaim,
5045 BTRFS_RESERVE_FLUSH_ALL, system_chunk))
5048 used = btrfs_space_info_used(space_info, true);
5050 if (can_overcommit(fs_info, space_info, SZ_1M,
5051 BTRFS_RESERVE_FLUSH_ALL, system_chunk))
5052 expected = div_factor_fine(space_info->total_bytes, 95);
5054 expected = div_factor_fine(space_info->total_bytes, 90);
5056 if (used > expected)
5057 to_reclaim = used - expected;
5060 to_reclaim = min(to_reclaim, space_info->bytes_may_use +
5061 space_info->bytes_reserved);
5065 static inline int need_do_async_reclaim(struct btrfs_fs_info *fs_info,
5066 struct btrfs_space_info *space_info,
5067 u64 used, bool system_chunk)
5069 u64 thresh = div_factor_fine(space_info->total_bytes, 98);
5071 /* If we're just plain full then async reclaim just slows us down. */
5072 if ((space_info->bytes_used + space_info->bytes_reserved) >= thresh)
5075 if (!btrfs_calc_reclaim_metadata_size(fs_info, space_info,
5079 return (used >= thresh && !btrfs_fs_closing(fs_info) &&
5080 !test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state));
5083 static void wake_all_tickets(struct list_head *head)
5085 struct reserve_ticket *ticket;
5087 while (!list_empty(head)) {
5088 ticket = list_first_entry(head, struct reserve_ticket, list);
5089 list_del_init(&ticket->list);
5090 ticket->error = -ENOSPC;
5091 wake_up(&ticket->wait);
5096 * This is for normal flushers, we can wait all goddamned day if we want to. We
5097 * will loop and continuously try to flush as long as we are making progress.
5098 * We count progress as clearing off tickets each time we have to loop.
5100 static void btrfs_async_reclaim_metadata_space(struct work_struct *work)
5102 struct btrfs_fs_info *fs_info;
5103 struct btrfs_space_info *space_info;
5106 int commit_cycles = 0;
5107 u64 last_tickets_id;
5109 fs_info = container_of(work, struct btrfs_fs_info, async_reclaim_work);
5110 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
5112 spin_lock(&space_info->lock);
5113 to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info,
5116 space_info->flush = 0;
5117 spin_unlock(&space_info->lock);
5120 last_tickets_id = space_info->tickets_id;
5121 spin_unlock(&space_info->lock);
5123 flush_state = FLUSH_DELAYED_ITEMS_NR;
5125 flush_space(fs_info, space_info, to_reclaim, flush_state);
5126 spin_lock(&space_info->lock);
5127 if (list_empty(&space_info->tickets)) {
5128 space_info->flush = 0;
5129 spin_unlock(&space_info->lock);
5132 to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info,
5135 if (last_tickets_id == space_info->tickets_id) {
5138 last_tickets_id = space_info->tickets_id;
5139 flush_state = FLUSH_DELAYED_ITEMS_NR;
5144 if (flush_state > COMMIT_TRANS) {
5146 if (commit_cycles > 2) {
5147 wake_all_tickets(&space_info->tickets);
5148 space_info->flush = 0;
5150 flush_state = FLUSH_DELAYED_ITEMS_NR;
5153 spin_unlock(&space_info->lock);
5154 } while (flush_state <= COMMIT_TRANS);
5157 void btrfs_init_async_reclaim_work(struct work_struct *work)
5159 INIT_WORK(work, btrfs_async_reclaim_metadata_space);
5162 static void priority_reclaim_metadata_space(struct btrfs_fs_info *fs_info,
5163 struct btrfs_space_info *space_info,
5164 struct reserve_ticket *ticket)
5167 int flush_state = FLUSH_DELAYED_ITEMS_NR;
5169 spin_lock(&space_info->lock);
5170 to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info,
5173 spin_unlock(&space_info->lock);
5176 spin_unlock(&space_info->lock);
5179 flush_space(fs_info, space_info, to_reclaim, flush_state);
5181 spin_lock(&space_info->lock);
5182 if (ticket->bytes == 0) {
5183 spin_unlock(&space_info->lock);
5186 spin_unlock(&space_info->lock);
5189 * Priority flushers can't wait on delalloc without
5192 if (flush_state == FLUSH_DELALLOC ||
5193 flush_state == FLUSH_DELALLOC_WAIT)
5194 flush_state = ALLOC_CHUNK;
5195 } while (flush_state < COMMIT_TRANS);
5198 static int wait_reserve_ticket(struct btrfs_fs_info *fs_info,
5199 struct btrfs_space_info *space_info,
5200 struct reserve_ticket *ticket, u64 orig_bytes)
5206 spin_lock(&space_info->lock);
5207 while (ticket->bytes > 0 && ticket->error == 0) {
5208 ret = prepare_to_wait_event(&ticket->wait, &wait, TASK_KILLABLE);
5213 spin_unlock(&space_info->lock);
5217 finish_wait(&ticket->wait, &wait);
5218 spin_lock(&space_info->lock);
5221 ret = ticket->error;
5222 if (!list_empty(&ticket->list))
5223 list_del_init(&ticket->list);
5224 if (ticket->bytes && ticket->bytes < orig_bytes) {
5225 u64 num_bytes = orig_bytes - ticket->bytes;
5226 space_info->bytes_may_use -= num_bytes;
5227 trace_btrfs_space_reservation(fs_info, "space_info",
5228 space_info->flags, num_bytes, 0);
5230 spin_unlock(&space_info->lock);
5236 * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
5237 * @root - the root we're allocating for
5238 * @space_info - the space info we want to allocate from
5239 * @orig_bytes - the number of bytes we want
5240 * @flush - whether or not we can flush to make our reservation
5242 * This will reserve orig_bytes number of bytes from the space info associated
5243 * with the block_rsv. If there is not enough space it will make an attempt to
5244 * flush out space to make room. It will do this by flushing delalloc if
5245 * possible or committing the transaction. If flush is 0 then no attempts to
5246 * regain reservations will be made and this will fail if there is not enough
5249 static int __reserve_metadata_bytes(struct btrfs_fs_info *fs_info,
5250 struct btrfs_space_info *space_info,
5252 enum btrfs_reserve_flush_enum flush,
5255 struct reserve_ticket ticket;
5260 ASSERT(!current->journal_info || flush != BTRFS_RESERVE_FLUSH_ALL);
5262 spin_lock(&space_info->lock);
5264 used = btrfs_space_info_used(space_info, true);
5267 * If we have enough space then hooray, make our reservation and carry
5268 * on. If not see if we can overcommit, and if we can, hooray carry on.
5269 * If not things get more complicated.
5271 if (used + orig_bytes <= space_info->total_bytes) {
5272 space_info->bytes_may_use += orig_bytes;
5273 trace_btrfs_space_reservation(fs_info, "space_info",
5274 space_info->flags, orig_bytes, 1);
5276 } else if (can_overcommit(fs_info, space_info, orig_bytes, flush,
5278 space_info->bytes_may_use += orig_bytes;
5279 trace_btrfs_space_reservation(fs_info, "space_info",
5280 space_info->flags, orig_bytes, 1);
5285 * If we couldn't make a reservation then setup our reservation ticket
5286 * and kick the async worker if it's not already running.
5288 * If we are a priority flusher then we just need to add our ticket to
5289 * the list and we will do our own flushing further down.
5291 if (ret && flush != BTRFS_RESERVE_NO_FLUSH) {
5292 ticket.bytes = orig_bytes;
5294 init_waitqueue_head(&ticket.wait);
5295 if (flush == BTRFS_RESERVE_FLUSH_ALL) {
5296 list_add_tail(&ticket.list, &space_info->tickets);
5297 if (!space_info->flush) {
5298 space_info->flush = 1;
5299 trace_btrfs_trigger_flush(fs_info,
5303 queue_work(system_unbound_wq,
5304 &fs_info->async_reclaim_work);
5307 list_add_tail(&ticket.list,
5308 &space_info->priority_tickets);
5310 } else if (!ret && space_info->flags & BTRFS_BLOCK_GROUP_METADATA) {
5313 * We will do the space reservation dance during log replay,
5314 * which means we won't have fs_info->fs_root set, so don't do
5315 * the async reclaim as we will panic.
5317 if (!test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags) &&
5318 need_do_async_reclaim(fs_info, space_info,
5319 used, system_chunk) &&
5320 !work_busy(&fs_info->async_reclaim_work)) {
5321 trace_btrfs_trigger_flush(fs_info, space_info->flags,
5322 orig_bytes, flush, "preempt");
5323 queue_work(system_unbound_wq,
5324 &fs_info->async_reclaim_work);
5327 spin_unlock(&space_info->lock);
5328 if (!ret || flush == BTRFS_RESERVE_NO_FLUSH)
5331 if (flush == BTRFS_RESERVE_FLUSH_ALL)
5332 return wait_reserve_ticket(fs_info, space_info, &ticket,
5336 priority_reclaim_metadata_space(fs_info, space_info, &ticket);
5337 spin_lock(&space_info->lock);
5339 if (ticket.bytes < orig_bytes) {
5340 u64 num_bytes = orig_bytes - ticket.bytes;
5341 space_info->bytes_may_use -= num_bytes;
5342 trace_btrfs_space_reservation(fs_info, "space_info",
5347 list_del_init(&ticket.list);
5350 spin_unlock(&space_info->lock);
5351 ASSERT(list_empty(&ticket.list));
5356 * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
5357 * @root - the root we're allocating for
5358 * @block_rsv - the block_rsv we're allocating for
5359 * @orig_bytes - the number of bytes we want
5360 * @flush - whether or not we can flush to make our reservation
5362 * This will reserve orgi_bytes number of bytes from the space info associated
5363 * with the block_rsv. If there is not enough space it will make an attempt to
5364 * flush out space to make room. It will do this by flushing delalloc if
5365 * possible or committing the transaction. If flush is 0 then no attempts to
5366 * regain reservations will be made and this will fail if there is not enough
5369 static int reserve_metadata_bytes(struct btrfs_root *root,
5370 struct btrfs_block_rsv *block_rsv,
5372 enum btrfs_reserve_flush_enum flush)
5374 struct btrfs_fs_info *fs_info = root->fs_info;
5375 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
5377 bool system_chunk = (root == fs_info->chunk_root);
5379 ret = __reserve_metadata_bytes(fs_info, block_rsv->space_info,
5380 orig_bytes, flush, system_chunk);
5381 if (ret == -ENOSPC &&
5382 unlikely(root->orphan_cleanup_state == ORPHAN_CLEANUP_STARTED)) {
5383 if (block_rsv != global_rsv &&
5384 !block_rsv_use_bytes(global_rsv, orig_bytes))
5387 if (ret == -ENOSPC) {
5388 trace_btrfs_space_reservation(fs_info, "space_info:enospc",
5389 block_rsv->space_info->flags,
5392 if (btrfs_test_opt(fs_info, ENOSPC_DEBUG))
5393 dump_space_info(fs_info, block_rsv->space_info,
5399 static struct btrfs_block_rsv *get_block_rsv(
5400 const struct btrfs_trans_handle *trans,
5401 const struct btrfs_root *root)
5403 struct btrfs_fs_info *fs_info = root->fs_info;
5404 struct btrfs_block_rsv *block_rsv = NULL;
5406 if (test_bit(BTRFS_ROOT_REF_COWS, &root->state) ||
5407 (root == fs_info->csum_root && trans->adding_csums) ||
5408 (root == fs_info->uuid_root))
5409 block_rsv = trans->block_rsv;
5412 block_rsv = root->block_rsv;
5415 block_rsv = &fs_info->empty_block_rsv;
5420 static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
5424 spin_lock(&block_rsv->lock);
5425 if (block_rsv->reserved >= num_bytes) {
5426 block_rsv->reserved -= num_bytes;
5427 if (block_rsv->reserved < block_rsv->size)
5428 block_rsv->full = 0;
5431 spin_unlock(&block_rsv->lock);
5435 static void block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
5436 u64 num_bytes, int update_size)
5438 spin_lock(&block_rsv->lock);
5439 block_rsv->reserved += num_bytes;
5441 block_rsv->size += num_bytes;
5442 else if (block_rsv->reserved >= block_rsv->size)
5443 block_rsv->full = 1;
5444 spin_unlock(&block_rsv->lock);
5447 int btrfs_cond_migrate_bytes(struct btrfs_fs_info *fs_info,
5448 struct btrfs_block_rsv *dest, u64 num_bytes,
5451 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
5454 if (global_rsv->space_info != dest->space_info)
5457 spin_lock(&global_rsv->lock);
5458 min_bytes = div_factor(global_rsv->size, min_factor);
5459 if (global_rsv->reserved < min_bytes + num_bytes) {
5460 spin_unlock(&global_rsv->lock);
5463 global_rsv->reserved -= num_bytes;
5464 if (global_rsv->reserved < global_rsv->size)
5465 global_rsv->full = 0;
5466 spin_unlock(&global_rsv->lock);
5468 block_rsv_add_bytes(dest, num_bytes, 1);
5473 * This is for space we already have accounted in space_info->bytes_may_use, so
5474 * basically when we're returning space from block_rsv's.
5476 static void space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
5477 struct btrfs_space_info *space_info,
5480 struct reserve_ticket *ticket;
5481 struct list_head *head;
5483 enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_NO_FLUSH;
5484 bool check_overcommit = false;
5486 spin_lock(&space_info->lock);
5487 head = &space_info->priority_tickets;
5490 * If we are over our limit then we need to check and see if we can
5491 * overcommit, and if we can't then we just need to free up our space
5492 * and not satisfy any requests.
5494 used = btrfs_space_info_used(space_info, true);
5495 if (used - num_bytes >= space_info->total_bytes)
5496 check_overcommit = true;
5498 while (!list_empty(head) && num_bytes) {
5499 ticket = list_first_entry(head, struct reserve_ticket,
5502 * We use 0 bytes because this space is already reserved, so
5503 * adding the ticket space would be a double count.
5505 if (check_overcommit &&
5506 !can_overcommit(fs_info, space_info, 0, flush, false))
5508 if (num_bytes >= ticket->bytes) {
5509 list_del_init(&ticket->list);
5510 num_bytes -= ticket->bytes;
5512 space_info->tickets_id++;
5513 wake_up(&ticket->wait);
5515 ticket->bytes -= num_bytes;
5520 if (num_bytes && head == &space_info->priority_tickets) {
5521 head = &space_info->tickets;
5522 flush = BTRFS_RESERVE_FLUSH_ALL;
5525 space_info->bytes_may_use -= num_bytes;
5526 trace_btrfs_space_reservation(fs_info, "space_info",
5527 space_info->flags, num_bytes, 0);
5528 spin_unlock(&space_info->lock);
5532 * This is for newly allocated space that isn't accounted in
5533 * space_info->bytes_may_use yet. So if we allocate a chunk or unpin an extent
5534 * we use this helper.
5536 static void space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
5537 struct btrfs_space_info *space_info,
5540 struct reserve_ticket *ticket;
5541 struct list_head *head = &space_info->priority_tickets;
5544 while (!list_empty(head) && num_bytes) {
5545 ticket = list_first_entry(head, struct reserve_ticket,
5547 if (num_bytes >= ticket->bytes) {
5548 trace_btrfs_space_reservation(fs_info, "space_info",
5551 list_del_init(&ticket->list);
5552 num_bytes -= ticket->bytes;
5553 space_info->bytes_may_use += ticket->bytes;
5555 space_info->tickets_id++;
5556 wake_up(&ticket->wait);
5558 trace_btrfs_space_reservation(fs_info, "space_info",
5561 space_info->bytes_may_use += num_bytes;
5562 ticket->bytes -= num_bytes;
5567 if (num_bytes && head == &space_info->priority_tickets) {
5568 head = &space_info->tickets;
5573 static u64 block_rsv_release_bytes(struct btrfs_fs_info *fs_info,
5574 struct btrfs_block_rsv *block_rsv,
5575 struct btrfs_block_rsv *dest, u64 num_bytes,
5576 u64 *qgroup_to_release_ret)
5578 struct btrfs_space_info *space_info = block_rsv->space_info;
5579 u64 qgroup_to_release = 0;
5582 spin_lock(&block_rsv->lock);
5583 if (num_bytes == (u64)-1) {
5584 num_bytes = block_rsv->size;
5585 qgroup_to_release = block_rsv->qgroup_rsv_size;
5587 block_rsv->size -= num_bytes;
5588 if (block_rsv->reserved >= block_rsv->size) {
5589 num_bytes = block_rsv->reserved - block_rsv->size;
5590 block_rsv->reserved = block_rsv->size;
5591 block_rsv->full = 1;
5595 if (block_rsv->qgroup_rsv_reserved >= block_rsv->qgroup_rsv_size) {
5596 qgroup_to_release = block_rsv->qgroup_rsv_reserved -
5597 block_rsv->qgroup_rsv_size;
5598 block_rsv->qgroup_rsv_reserved = block_rsv->qgroup_rsv_size;
5600 qgroup_to_release = 0;
5602 spin_unlock(&block_rsv->lock);
5605 if (num_bytes > 0) {
5607 spin_lock(&dest->lock);
5611 bytes_to_add = dest->size - dest->reserved;
5612 bytes_to_add = min(num_bytes, bytes_to_add);
5613 dest->reserved += bytes_to_add;
5614 if (dest->reserved >= dest->size)
5616 num_bytes -= bytes_to_add;
5618 spin_unlock(&dest->lock);
5621 space_info_add_old_bytes(fs_info, space_info,
5624 if (qgroup_to_release_ret)
5625 *qgroup_to_release_ret = qgroup_to_release;
5629 int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src,
5630 struct btrfs_block_rsv *dst, u64 num_bytes,
5635 ret = block_rsv_use_bytes(src, num_bytes);
5639 block_rsv_add_bytes(dst, num_bytes, update_size);
5643 void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv, unsigned short type)
5645 memset(rsv, 0, sizeof(*rsv));
5646 spin_lock_init(&rsv->lock);
5650 void btrfs_init_metadata_block_rsv(struct btrfs_fs_info *fs_info,
5651 struct btrfs_block_rsv *rsv,
5652 unsigned short type)
5654 btrfs_init_block_rsv(rsv, type);
5655 rsv->space_info = __find_space_info(fs_info,
5656 BTRFS_BLOCK_GROUP_METADATA);
5659 struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_fs_info *fs_info,
5660 unsigned short type)
5662 struct btrfs_block_rsv *block_rsv;
5664 block_rsv = kmalloc(sizeof(*block_rsv), GFP_NOFS);
5668 btrfs_init_metadata_block_rsv(fs_info, block_rsv, type);
5672 void btrfs_free_block_rsv(struct btrfs_fs_info *fs_info,
5673 struct btrfs_block_rsv *rsv)
5677 btrfs_block_rsv_release(fs_info, rsv, (u64)-1);
5681 void __btrfs_free_block_rsv(struct btrfs_block_rsv *rsv)
5686 int btrfs_block_rsv_add(struct btrfs_root *root,
5687 struct btrfs_block_rsv *block_rsv, u64 num_bytes,
5688 enum btrfs_reserve_flush_enum flush)
5695 ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
5697 block_rsv_add_bytes(block_rsv, num_bytes, 1);
5704 int btrfs_block_rsv_check(struct btrfs_block_rsv *block_rsv, int min_factor)
5712 spin_lock(&block_rsv->lock);
5713 num_bytes = div_factor(block_rsv->size, min_factor);
5714 if (block_rsv->reserved >= num_bytes)
5716 spin_unlock(&block_rsv->lock);
5721 int btrfs_block_rsv_refill(struct btrfs_root *root,
5722 struct btrfs_block_rsv *block_rsv, u64 min_reserved,
5723 enum btrfs_reserve_flush_enum flush)
5731 spin_lock(&block_rsv->lock);
5732 num_bytes = min_reserved;
5733 if (block_rsv->reserved >= num_bytes)
5736 num_bytes -= block_rsv->reserved;
5737 spin_unlock(&block_rsv->lock);
5742 ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
5744 block_rsv_add_bytes(block_rsv, num_bytes, 0);
5752 * btrfs_inode_rsv_refill - refill the inode block rsv.
5753 * @inode - the inode we are refilling.
5754 * @flush - the flusing restriction.
5756 * Essentially the same as btrfs_block_rsv_refill, except it uses the
5757 * block_rsv->size as the minimum size. We'll either refill the missing amount
5758 * or return if we already have enough space. This will also handle the resreve
5759 * tracepoint for the reserved amount.
5761 static int btrfs_inode_rsv_refill(struct btrfs_inode *inode,
5762 enum btrfs_reserve_flush_enum flush)
5764 struct btrfs_root *root = inode->root;
5765 struct btrfs_block_rsv *block_rsv = &inode->block_rsv;
5767 u64 qgroup_num_bytes = 0;
5770 spin_lock(&block_rsv->lock);
5771 if (block_rsv->reserved < block_rsv->size)
5772 num_bytes = block_rsv->size - block_rsv->reserved;
5773 if (block_rsv->qgroup_rsv_reserved < block_rsv->qgroup_rsv_size)
5774 qgroup_num_bytes = block_rsv->qgroup_rsv_size -
5775 block_rsv->qgroup_rsv_reserved;
5776 spin_unlock(&block_rsv->lock);
5781 ret = btrfs_qgroup_reserve_meta_prealloc(root, qgroup_num_bytes, true);
5784 ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
5786 block_rsv_add_bytes(block_rsv, num_bytes, 0);
5787 trace_btrfs_space_reservation(root->fs_info, "delalloc",
5788 btrfs_ino(inode), num_bytes, 1);
5790 /* Don't forget to increase qgroup_rsv_reserved */
5791 spin_lock(&block_rsv->lock);
5792 block_rsv->qgroup_rsv_reserved += qgroup_num_bytes;
5793 spin_unlock(&block_rsv->lock);
5795 btrfs_qgroup_free_meta_prealloc(root, qgroup_num_bytes);
5800 * btrfs_inode_rsv_release - release any excessive reservation.
5801 * @inode - the inode we need to release from.
5802 * @qgroup_free - free or convert qgroup meta.
5803 * Unlike normal operation, qgroup meta reservation needs to know if we are
5804 * freeing qgroup reservation or just converting it into per-trans. Normally
5805 * @qgroup_free is true for error handling, and false for normal release.
5807 * This is the same as btrfs_block_rsv_release, except that it handles the
5808 * tracepoint for the reservation.
5810 static void btrfs_inode_rsv_release(struct btrfs_inode *inode, bool qgroup_free)
5812 struct btrfs_fs_info *fs_info = inode->root->fs_info;
5813 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
5814 struct btrfs_block_rsv *block_rsv = &inode->block_rsv;
5816 u64 qgroup_to_release = 0;
5819 * Since we statically set the block_rsv->size we just want to say we
5820 * are releasing 0 bytes, and then we'll just get the reservation over
5823 released = block_rsv_release_bytes(fs_info, block_rsv, global_rsv, 0,
5824 &qgroup_to_release);
5826 trace_btrfs_space_reservation(fs_info, "delalloc",
5827 btrfs_ino(inode), released, 0);
5829 btrfs_qgroup_free_meta_prealloc(inode->root, qgroup_to_release);
5831 btrfs_qgroup_convert_reserved_meta(inode->root,
5835 void btrfs_block_rsv_release(struct btrfs_fs_info *fs_info,
5836 struct btrfs_block_rsv *block_rsv,
5839 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
5841 if (global_rsv == block_rsv ||
5842 block_rsv->space_info != global_rsv->space_info)
5844 block_rsv_release_bytes(fs_info, block_rsv, global_rsv, num_bytes, NULL);
5847 static void update_global_block_rsv(struct btrfs_fs_info *fs_info)
5849 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
5850 struct btrfs_space_info *sinfo = block_rsv->space_info;
5854 * The global block rsv is based on the size of the extent tree, the
5855 * checksum tree and the root tree. If the fs is empty we want to set
5856 * it to a minimal amount for safety.
5858 num_bytes = btrfs_root_used(&fs_info->extent_root->root_item) +
5859 btrfs_root_used(&fs_info->csum_root->root_item) +
5860 btrfs_root_used(&fs_info->tree_root->root_item);
5861 num_bytes = max_t(u64, num_bytes, SZ_16M);
5863 spin_lock(&sinfo->lock);
5864 spin_lock(&block_rsv->lock);
5866 block_rsv->size = min_t(u64, num_bytes, SZ_512M);
5868 if (block_rsv->reserved < block_rsv->size) {
5869 num_bytes = btrfs_space_info_used(sinfo, true);
5870 if (sinfo->total_bytes > num_bytes) {
5871 num_bytes = sinfo->total_bytes - num_bytes;
5872 num_bytes = min(num_bytes,
5873 block_rsv->size - block_rsv->reserved);
5874 block_rsv->reserved += num_bytes;
5875 sinfo->bytes_may_use += num_bytes;
5876 trace_btrfs_space_reservation(fs_info, "space_info",
5877 sinfo->flags, num_bytes,
5880 } else if (block_rsv->reserved > block_rsv->size) {
5881 num_bytes = block_rsv->reserved - block_rsv->size;
5882 sinfo->bytes_may_use -= num_bytes;
5883 trace_btrfs_space_reservation(fs_info, "space_info",
5884 sinfo->flags, num_bytes, 0);
5885 block_rsv->reserved = block_rsv->size;
5888 if (block_rsv->reserved == block_rsv->size)
5889 block_rsv->full = 1;
5891 block_rsv->full = 0;
5893 spin_unlock(&block_rsv->lock);
5894 spin_unlock(&sinfo->lock);
5897 static void init_global_block_rsv(struct btrfs_fs_info *fs_info)
5899 struct btrfs_space_info *space_info;
5901 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
5902 fs_info->chunk_block_rsv.space_info = space_info;
5904 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
5905 fs_info->global_block_rsv.space_info = space_info;
5906 fs_info->trans_block_rsv.space_info = space_info;
5907 fs_info->empty_block_rsv.space_info = space_info;
5908 fs_info->delayed_block_rsv.space_info = space_info;
5910 fs_info->extent_root->block_rsv = &fs_info->global_block_rsv;
5911 fs_info->csum_root->block_rsv = &fs_info->global_block_rsv;
5912 fs_info->dev_root->block_rsv = &fs_info->global_block_rsv;
5913 fs_info->tree_root->block_rsv = &fs_info->global_block_rsv;
5914 if (fs_info->quota_root)
5915 fs_info->quota_root->block_rsv = &fs_info->global_block_rsv;
5916 fs_info->chunk_root->block_rsv = &fs_info->chunk_block_rsv;
5918 update_global_block_rsv(fs_info);
5921 static void release_global_block_rsv(struct btrfs_fs_info *fs_info)
5923 block_rsv_release_bytes(fs_info, &fs_info->global_block_rsv, NULL,
5925 WARN_ON(fs_info->trans_block_rsv.size > 0);
5926 WARN_ON(fs_info->trans_block_rsv.reserved > 0);
5927 WARN_ON(fs_info->chunk_block_rsv.size > 0);
5928 WARN_ON(fs_info->chunk_block_rsv.reserved > 0);
5929 WARN_ON(fs_info->delayed_block_rsv.size > 0);
5930 WARN_ON(fs_info->delayed_block_rsv.reserved > 0);
5935 * To be called after all the new block groups attached to the transaction
5936 * handle have been created (btrfs_create_pending_block_groups()).
5938 void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans)
5940 struct btrfs_fs_info *fs_info = trans->fs_info;
5942 if (!trans->chunk_bytes_reserved)
5945 WARN_ON_ONCE(!list_empty(&trans->new_bgs));
5947 block_rsv_release_bytes(fs_info, &fs_info->chunk_block_rsv, NULL,
5948 trans->chunk_bytes_reserved, NULL);
5949 trans->chunk_bytes_reserved = 0;
5952 /* Can only return 0 or -ENOSPC */
5953 int btrfs_orphan_reserve_metadata(struct btrfs_trans_handle *trans,
5954 struct btrfs_inode *inode)
5956 struct btrfs_fs_info *fs_info = btrfs_sb(inode->vfs_inode.i_sb);
5957 struct btrfs_root *root = inode->root;
5959 * We always use trans->block_rsv here as we will have reserved space
5960 * for our orphan when starting the transaction, using get_block_rsv()
5961 * here will sometimes make us choose the wrong block rsv as we could be
5962 * doing a reloc inode for a non refcounted root.
5964 struct btrfs_block_rsv *src_rsv = trans->block_rsv;
5965 struct btrfs_block_rsv *dst_rsv = root->orphan_block_rsv;
5968 * We need to hold space in order to delete our orphan item once we've
5969 * added it, so this takes the reservation so we can release it later
5970 * when we are truly done with the orphan item.
5972 u64 num_bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
5974 trace_btrfs_space_reservation(fs_info, "orphan", btrfs_ino(inode),
5976 return btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes, 1);
5979 void btrfs_orphan_release_metadata(struct btrfs_inode *inode)
5981 struct btrfs_fs_info *fs_info = btrfs_sb(inode->vfs_inode.i_sb);
5982 struct btrfs_root *root = inode->root;
5983 u64 num_bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
5985 trace_btrfs_space_reservation(fs_info, "orphan", btrfs_ino(inode),
5987 btrfs_block_rsv_release(fs_info, root->orphan_block_rsv, num_bytes);
5991 * btrfs_subvolume_reserve_metadata() - reserve space for subvolume operation
5992 * root: the root of the parent directory
5993 * rsv: block reservation
5994 * items: the number of items that we need do reservation
5995 * qgroup_reserved: used to return the reserved size in qgroup
5997 * This function is used to reserve the space for snapshot/subvolume
5998 * creation and deletion. Those operations are different with the
5999 * common file/directory operations, they change two fs/file trees
6000 * and root tree, the number of items that the qgroup reserves is
6001 * different with the free space reservation. So we can not use
6002 * the space reservation mechanism in start_transaction().
6004 int btrfs_subvolume_reserve_metadata(struct btrfs_root *root,
6005 struct btrfs_block_rsv *rsv,
6007 u64 *qgroup_reserved,
6008 bool use_global_rsv)
6012 struct btrfs_fs_info *fs_info = root->fs_info;
6013 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
6015 if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)) {
6016 /* One for parent inode, two for dir entries */
6017 num_bytes = 3 * fs_info->nodesize;
6018 ret = btrfs_qgroup_reserve_meta_prealloc(root, num_bytes, true);
6025 *qgroup_reserved = num_bytes;
6027 num_bytes = btrfs_calc_trans_metadata_size(fs_info, items);
6028 rsv->space_info = __find_space_info(fs_info,
6029 BTRFS_BLOCK_GROUP_METADATA);
6030 ret = btrfs_block_rsv_add(root, rsv, num_bytes,
6031 BTRFS_RESERVE_FLUSH_ALL);
6033 if (ret == -ENOSPC && use_global_rsv)
6034 ret = btrfs_block_rsv_migrate(global_rsv, rsv, num_bytes, 1);
6036 if (ret && *qgroup_reserved)
6037 btrfs_qgroup_free_meta_prealloc(root, *qgroup_reserved);
6042 void btrfs_subvolume_release_metadata(struct btrfs_fs_info *fs_info,
6043 struct btrfs_block_rsv *rsv)
6045 btrfs_block_rsv_release(fs_info, rsv, (u64)-1);
6048 static void btrfs_calculate_inode_block_rsv_size(struct btrfs_fs_info *fs_info,
6049 struct btrfs_inode *inode)
6051 struct btrfs_block_rsv *block_rsv = &inode->block_rsv;
6052 u64 reserve_size = 0;
6053 u64 qgroup_rsv_size = 0;
6055 unsigned outstanding_extents;
6057 lockdep_assert_held(&inode->lock);
6058 outstanding_extents = inode->outstanding_extents;
6059 if (outstanding_extents)
6060 reserve_size = btrfs_calc_trans_metadata_size(fs_info,
6061 outstanding_extents + 1);
6062 csum_leaves = btrfs_csum_bytes_to_leaves(fs_info,
6064 reserve_size += btrfs_calc_trans_metadata_size(fs_info,
6067 * For qgroup rsv, the calculation is very simple:
6068 * account one nodesize for each outstanding extent
6070 * This is overestimating in most cases.
6072 qgroup_rsv_size = outstanding_extents * fs_info->nodesize;
6074 spin_lock(&block_rsv->lock);
6075 block_rsv->size = reserve_size;
6076 block_rsv->qgroup_rsv_size = qgroup_rsv_size;
6077 spin_unlock(&block_rsv->lock);
6080 int btrfs_delalloc_reserve_metadata(struct btrfs_inode *inode, u64 num_bytes)
6082 struct btrfs_fs_info *fs_info = btrfs_sb(inode->vfs_inode.i_sb);
6083 unsigned nr_extents;
6084 enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_FLUSH_ALL;
6086 bool delalloc_lock = true;
6088 /* If we are a free space inode we need to not flush since we will be in
6089 * the middle of a transaction commit. We also don't need the delalloc
6090 * mutex since we won't race with anybody. We need this mostly to make
6091 * lockdep shut its filthy mouth.
6093 * If we have a transaction open (can happen if we call truncate_block
6094 * from truncate), then we need FLUSH_LIMIT so we don't deadlock.
6096 if (btrfs_is_free_space_inode(inode)) {
6097 flush = BTRFS_RESERVE_NO_FLUSH;
6098 delalloc_lock = false;
6100 if (current->journal_info)
6101 flush = BTRFS_RESERVE_FLUSH_LIMIT;
6103 if (btrfs_transaction_in_commit(fs_info))
6104 schedule_timeout(1);
6108 mutex_lock(&inode->delalloc_mutex);
6110 num_bytes = ALIGN(num_bytes, fs_info->sectorsize);
6112 /* Add our new extents and calculate the new rsv size. */
6113 spin_lock(&inode->lock);
6114 nr_extents = count_max_extents(num_bytes);
6115 btrfs_mod_outstanding_extents(inode, nr_extents);
6116 inode->csum_bytes += num_bytes;
6117 btrfs_calculate_inode_block_rsv_size(fs_info, inode);
6118 spin_unlock(&inode->lock);
6120 ret = btrfs_inode_rsv_refill(inode, flush);
6125 mutex_unlock(&inode->delalloc_mutex);
6129 spin_lock(&inode->lock);
6130 nr_extents = count_max_extents(num_bytes);
6131 btrfs_mod_outstanding_extents(inode, -nr_extents);
6132 inode->csum_bytes -= num_bytes;
6133 btrfs_calculate_inode_block_rsv_size(fs_info, inode);
6134 spin_unlock(&inode->lock);
6136 btrfs_inode_rsv_release(inode, true);
6138 mutex_unlock(&inode->delalloc_mutex);
6143 * btrfs_delalloc_release_metadata - release a metadata reservation for an inode
6144 * @inode: the inode to release the reservation for.
6145 * @num_bytes: the number of bytes we are releasing.
6146 * @qgroup_free: free qgroup reservation or convert it to per-trans reservation
6148 * This will release the metadata reservation for an inode. This can be called
6149 * once we complete IO for a given set of bytes to release their metadata
6150 * reservations, or on error for the same reason.
6152 void btrfs_delalloc_release_metadata(struct btrfs_inode *inode, u64 num_bytes,
6155 struct btrfs_fs_info *fs_info = btrfs_sb(inode->vfs_inode.i_sb);
6157 num_bytes = ALIGN(num_bytes, fs_info->sectorsize);
6158 spin_lock(&inode->lock);
6159 inode->csum_bytes -= num_bytes;
6160 btrfs_calculate_inode_block_rsv_size(fs_info, inode);
6161 spin_unlock(&inode->lock);
6163 if (btrfs_is_testing(fs_info))
6166 btrfs_inode_rsv_release(inode, qgroup_free);
6170 * btrfs_delalloc_release_extents - release our outstanding_extents
6171 * @inode: the inode to balance the reservation for.
6172 * @num_bytes: the number of bytes we originally reserved with
6173 * @qgroup_free: do we need to free qgroup meta reservation or convert them.
6175 * When we reserve space we increase outstanding_extents for the extents we may
6176 * add. Once we've set the range as delalloc or created our ordered extents we
6177 * have outstanding_extents to track the real usage, so we use this to free our
6178 * temporarily tracked outstanding_extents. This _must_ be used in conjunction
6179 * with btrfs_delalloc_reserve_metadata.
6181 void btrfs_delalloc_release_extents(struct btrfs_inode *inode, u64 num_bytes,
6184 struct btrfs_fs_info *fs_info = btrfs_sb(inode->vfs_inode.i_sb);
6185 unsigned num_extents;
6187 spin_lock(&inode->lock);
6188 num_extents = count_max_extents(num_bytes);
6189 btrfs_mod_outstanding_extents(inode, -num_extents);
6190 btrfs_calculate_inode_block_rsv_size(fs_info, inode);
6191 spin_unlock(&inode->lock);
6193 if (btrfs_is_testing(fs_info))
6196 btrfs_inode_rsv_release(inode, qgroup_free);
6200 * btrfs_delalloc_reserve_space - reserve data and metadata space for
6202 * @inode: inode we're writing to
6203 * @start: start range we are writing to
6204 * @len: how long the range we are writing to
6205 * @reserved: mandatory parameter, record actually reserved qgroup ranges of
6206 * current reservation.
6208 * This will do the following things
6210 * o reserve space in data space info for num bytes
6211 * and reserve precious corresponding qgroup space
6212 * (Done in check_data_free_space)
6214 * o reserve space for metadata space, based on the number of outstanding
6215 * extents and how much csums will be needed
6216 * also reserve metadata space in a per root over-reserve method.
6217 * o add to the inodes->delalloc_bytes
6218 * o add it to the fs_info's delalloc inodes list.
6219 * (Above 3 all done in delalloc_reserve_metadata)
6221 * Return 0 for success
6222 * Return <0 for error(-ENOSPC or -EQUOT)
6224 int btrfs_delalloc_reserve_space(struct inode *inode,
6225 struct extent_changeset **reserved, u64 start, u64 len)
6229 ret = btrfs_check_data_free_space(inode, reserved, start, len);
6232 ret = btrfs_delalloc_reserve_metadata(BTRFS_I(inode), len);
6234 btrfs_free_reserved_data_space(inode, *reserved, start, len);
6239 * btrfs_delalloc_release_space - release data and metadata space for delalloc
6240 * @inode: inode we're releasing space for
6241 * @start: start position of the space already reserved
6242 * @len: the len of the space already reserved
6243 * @release_bytes: the len of the space we consumed or didn't use
6245 * This function will release the metadata space that was not used and will
6246 * decrement ->delalloc_bytes and remove it from the fs_info delalloc_inodes
6247 * list if there are no delalloc bytes left.
6248 * Also it will handle the qgroup reserved space.
6250 void btrfs_delalloc_release_space(struct inode *inode,
6251 struct extent_changeset *reserved,
6252 u64 start, u64 len, bool qgroup_free)
6254 btrfs_delalloc_release_metadata(BTRFS_I(inode), len, qgroup_free);
6255 btrfs_free_reserved_data_space(inode, reserved, start, len);
6258 static int update_block_group(struct btrfs_trans_handle *trans,
6259 struct btrfs_fs_info *info, u64 bytenr,
6260 u64 num_bytes, int alloc)
6262 struct btrfs_block_group_cache *cache = NULL;
6263 u64 total = num_bytes;
6268 /* block accounting for super block */
6269 spin_lock(&info->delalloc_root_lock);
6270 old_val = btrfs_super_bytes_used(info->super_copy);
6272 old_val += num_bytes;
6274 old_val -= num_bytes;
6275 btrfs_set_super_bytes_used(info->super_copy, old_val);
6276 spin_unlock(&info->delalloc_root_lock);
6279 cache = btrfs_lookup_block_group(info, bytenr);
6282 if (cache->flags & (BTRFS_BLOCK_GROUP_DUP |
6283 BTRFS_BLOCK_GROUP_RAID1 |
6284 BTRFS_BLOCK_GROUP_RAID10))
6289 * If this block group has free space cache written out, we
6290 * need to make sure to load it if we are removing space. This
6291 * is because we need the unpinning stage to actually add the
6292 * space back to the block group, otherwise we will leak space.
6294 if (!alloc && cache->cached == BTRFS_CACHE_NO)
6295 cache_block_group(cache, 1);
6297 byte_in_group = bytenr - cache->key.objectid;
6298 WARN_ON(byte_in_group > cache->key.offset);
6300 spin_lock(&cache->space_info->lock);
6301 spin_lock(&cache->lock);
6303 if (btrfs_test_opt(info, SPACE_CACHE) &&
6304 cache->disk_cache_state < BTRFS_DC_CLEAR)
6305 cache->disk_cache_state = BTRFS_DC_CLEAR;
6307 old_val = btrfs_block_group_used(&cache->item);
6308 num_bytes = min(total, cache->key.offset - byte_in_group);
6310 old_val += num_bytes;
6311 btrfs_set_block_group_used(&cache->item, old_val);
6312 cache->reserved -= num_bytes;
6313 cache->space_info->bytes_reserved -= num_bytes;
6314 cache->space_info->bytes_used += num_bytes;
6315 cache->space_info->disk_used += num_bytes * factor;
6316 spin_unlock(&cache->lock);
6317 spin_unlock(&cache->space_info->lock);
6319 old_val -= num_bytes;
6320 btrfs_set_block_group_used(&cache->item, old_val);
6321 cache->pinned += num_bytes;
6322 cache->space_info->bytes_pinned += num_bytes;
6323 cache->space_info->bytes_used -= num_bytes;
6324 cache->space_info->disk_used -= num_bytes * factor;
6325 spin_unlock(&cache->lock);
6326 spin_unlock(&cache->space_info->lock);
6328 trace_btrfs_space_reservation(info, "pinned",
6329 cache->space_info->flags,
6331 percpu_counter_add(&cache->space_info->total_bytes_pinned,
6333 set_extent_dirty(info->pinned_extents,
6334 bytenr, bytenr + num_bytes - 1,
6335 GFP_NOFS | __GFP_NOFAIL);
6338 spin_lock(&trans->transaction->dirty_bgs_lock);
6339 if (list_empty(&cache->dirty_list)) {
6340 list_add_tail(&cache->dirty_list,
6341 &trans->transaction->dirty_bgs);
6342 trans->transaction->num_dirty_bgs++;
6343 btrfs_get_block_group(cache);
6345 spin_unlock(&trans->transaction->dirty_bgs_lock);
6348 * No longer have used bytes in this block group, queue it for
6349 * deletion. We do this after adding the block group to the
6350 * dirty list to avoid races between cleaner kthread and space
6353 if (!alloc && old_val == 0) {
6354 spin_lock(&info->unused_bgs_lock);
6355 if (list_empty(&cache->bg_list)) {
6356 btrfs_get_block_group(cache);
6357 list_add_tail(&cache->bg_list,
6360 spin_unlock(&info->unused_bgs_lock);
6363 btrfs_put_block_group(cache);
6365 bytenr += num_bytes;
6370 static u64 first_logical_byte(struct btrfs_fs_info *fs_info, u64 search_start)
6372 struct btrfs_block_group_cache *cache;
6375 spin_lock(&fs_info->block_group_cache_lock);
6376 bytenr = fs_info->first_logical_byte;
6377 spin_unlock(&fs_info->block_group_cache_lock);
6379 if (bytenr < (u64)-1)
6382 cache = btrfs_lookup_first_block_group(fs_info, search_start);
6386 bytenr = cache->key.objectid;
6387 btrfs_put_block_group(cache);
6392 static int pin_down_extent(struct btrfs_fs_info *fs_info,
6393 struct btrfs_block_group_cache *cache,
6394 u64 bytenr, u64 num_bytes, int reserved)
6396 spin_lock(&cache->space_info->lock);
6397 spin_lock(&cache->lock);
6398 cache->pinned += num_bytes;
6399 cache->space_info->bytes_pinned += num_bytes;
6401 cache->reserved -= num_bytes;
6402 cache->space_info->bytes_reserved -= num_bytes;
6404 spin_unlock(&cache->lock);
6405 spin_unlock(&cache->space_info->lock);
6407 trace_btrfs_space_reservation(fs_info, "pinned",
6408 cache->space_info->flags, num_bytes, 1);
6409 percpu_counter_add(&cache->space_info->total_bytes_pinned, num_bytes);
6410 set_extent_dirty(fs_info->pinned_extents, bytenr,
6411 bytenr + num_bytes - 1, GFP_NOFS | __GFP_NOFAIL);
6416 * this function must be called within transaction
6418 int btrfs_pin_extent(struct btrfs_fs_info *fs_info,
6419 u64 bytenr, u64 num_bytes, int reserved)
6421 struct btrfs_block_group_cache *cache;
6423 cache = btrfs_lookup_block_group(fs_info, bytenr);
6424 BUG_ON(!cache); /* Logic error */
6426 pin_down_extent(fs_info, cache, bytenr, num_bytes, reserved);
6428 btrfs_put_block_group(cache);
6433 * this function must be called within transaction
6435 int btrfs_pin_extent_for_log_replay(struct btrfs_fs_info *fs_info,
6436 u64 bytenr, u64 num_bytes)
6438 struct btrfs_block_group_cache *cache;
6441 cache = btrfs_lookup_block_group(fs_info, bytenr);
6446 * pull in the free space cache (if any) so that our pin
6447 * removes the free space from the cache. We have load_only set
6448 * to one because the slow code to read in the free extents does check
6449 * the pinned extents.
6451 cache_block_group(cache, 1);
6453 pin_down_extent(fs_info, cache, bytenr, num_bytes, 0);
6455 /* remove us from the free space cache (if we're there at all) */
6456 ret = btrfs_remove_free_space(cache, bytenr, num_bytes);
6457 btrfs_put_block_group(cache);
6461 static int __exclude_logged_extent(struct btrfs_fs_info *fs_info,
6462 u64 start, u64 num_bytes)
6465 struct btrfs_block_group_cache *block_group;
6466 struct btrfs_caching_control *caching_ctl;
6468 block_group = btrfs_lookup_block_group(fs_info, start);
6472 cache_block_group(block_group, 0);
6473 caching_ctl = get_caching_control(block_group);
6477 BUG_ON(!block_group_cache_done(block_group));
6478 ret = btrfs_remove_free_space(block_group, start, num_bytes);
6480 mutex_lock(&caching_ctl->mutex);
6482 if (start >= caching_ctl->progress) {
6483 ret = add_excluded_extent(fs_info, start, num_bytes);
6484 } else if (start + num_bytes <= caching_ctl->progress) {
6485 ret = btrfs_remove_free_space(block_group,
6488 num_bytes = caching_ctl->progress - start;
6489 ret = btrfs_remove_free_space(block_group,
6494 num_bytes = (start + num_bytes) -
6495 caching_ctl->progress;
6496 start = caching_ctl->progress;
6497 ret = add_excluded_extent(fs_info, start, num_bytes);
6500 mutex_unlock(&caching_ctl->mutex);
6501 put_caching_control(caching_ctl);
6503 btrfs_put_block_group(block_group);
6507 int btrfs_exclude_logged_extents(struct btrfs_fs_info *fs_info,
6508 struct extent_buffer *eb)
6510 struct btrfs_file_extent_item *item;
6511 struct btrfs_key key;
6515 if (!btrfs_fs_incompat(fs_info, MIXED_GROUPS))
6518 for (i = 0; i < btrfs_header_nritems(eb); i++) {
6519 btrfs_item_key_to_cpu(eb, &key, i);
6520 if (key.type != BTRFS_EXTENT_DATA_KEY)
6522 item = btrfs_item_ptr(eb, i, struct btrfs_file_extent_item);
6523 found_type = btrfs_file_extent_type(eb, item);
6524 if (found_type == BTRFS_FILE_EXTENT_INLINE)
6526 if (btrfs_file_extent_disk_bytenr(eb, item) == 0)
6528 key.objectid = btrfs_file_extent_disk_bytenr(eb, item);
6529 key.offset = btrfs_file_extent_disk_num_bytes(eb, item);
6530 __exclude_logged_extent(fs_info, key.objectid, key.offset);
6537 btrfs_inc_block_group_reservations(struct btrfs_block_group_cache *bg)
6539 atomic_inc(&bg->reservations);
6542 void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info,
6545 struct btrfs_block_group_cache *bg;
6547 bg = btrfs_lookup_block_group(fs_info, start);
6549 if (atomic_dec_and_test(&bg->reservations))
6550 wake_up_var(&bg->reservations);
6551 btrfs_put_block_group(bg);
6554 void btrfs_wait_block_group_reservations(struct btrfs_block_group_cache *bg)
6556 struct btrfs_space_info *space_info = bg->space_info;
6560 if (!(bg->flags & BTRFS_BLOCK_GROUP_DATA))
6564 * Our block group is read only but before we set it to read only,
6565 * some task might have had allocated an extent from it already, but it
6566 * has not yet created a respective ordered extent (and added it to a
6567 * root's list of ordered extents).
6568 * Therefore wait for any task currently allocating extents, since the
6569 * block group's reservations counter is incremented while a read lock
6570 * on the groups' semaphore is held and decremented after releasing
6571 * the read access on that semaphore and creating the ordered extent.
6573 down_write(&space_info->groups_sem);
6574 up_write(&space_info->groups_sem);
6576 wait_var_event(&bg->reservations, !atomic_read(&bg->reservations));
6580 * btrfs_add_reserved_bytes - update the block_group and space info counters
6581 * @cache: The cache we are manipulating
6582 * @ram_bytes: The number of bytes of file content, and will be same to
6583 * @num_bytes except for the compress path.
6584 * @num_bytes: The number of bytes in question
6585 * @delalloc: The blocks are allocated for the delalloc write
6587 * This is called by the allocator when it reserves space. If this is a
6588 * reservation and the block group has become read only we cannot make the
6589 * reservation and return -EAGAIN, otherwise this function always succeeds.
6591 static int btrfs_add_reserved_bytes(struct btrfs_block_group_cache *cache,
6592 u64 ram_bytes, u64 num_bytes, int delalloc)
6594 struct btrfs_space_info *space_info = cache->space_info;
6597 spin_lock(&space_info->lock);
6598 spin_lock(&cache->lock);
6602 cache->reserved += num_bytes;
6603 space_info->bytes_reserved += num_bytes;
6605 trace_btrfs_space_reservation(cache->fs_info,
6606 "space_info", space_info->flags,
6608 space_info->bytes_may_use -= ram_bytes;
6610 cache->delalloc_bytes += num_bytes;
6612 spin_unlock(&cache->lock);
6613 spin_unlock(&space_info->lock);
6618 * btrfs_free_reserved_bytes - update the block_group and space info counters
6619 * @cache: The cache we are manipulating
6620 * @num_bytes: The number of bytes in question
6621 * @delalloc: The blocks are allocated for the delalloc write
6623 * This is called by somebody who is freeing space that was never actually used
6624 * on disk. For example if you reserve some space for a new leaf in transaction
6625 * A and before transaction A commits you free that leaf, you call this with
6626 * reserve set to 0 in order to clear the reservation.
6629 static int btrfs_free_reserved_bytes(struct btrfs_block_group_cache *cache,
6630 u64 num_bytes, int delalloc)
6632 struct btrfs_space_info *space_info = cache->space_info;
6635 spin_lock(&space_info->lock);
6636 spin_lock(&cache->lock);
6638 space_info->bytes_readonly += num_bytes;
6639 cache->reserved -= num_bytes;
6640 space_info->bytes_reserved -= num_bytes;
6643 cache->delalloc_bytes -= num_bytes;
6644 spin_unlock(&cache->lock);
6645 spin_unlock(&space_info->lock);
6648 void btrfs_prepare_extent_commit(struct btrfs_fs_info *fs_info)
6650 struct btrfs_caching_control *next;
6651 struct btrfs_caching_control *caching_ctl;
6652 struct btrfs_block_group_cache *cache;
6654 down_write(&fs_info->commit_root_sem);
6656 list_for_each_entry_safe(caching_ctl, next,
6657 &fs_info->caching_block_groups, list) {
6658 cache = caching_ctl->block_group;
6659 if (block_group_cache_done(cache)) {
6660 cache->last_byte_to_unpin = (u64)-1;
6661 list_del_init(&caching_ctl->list);
6662 put_caching_control(caching_ctl);
6664 cache->last_byte_to_unpin = caching_ctl->progress;
6668 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
6669 fs_info->pinned_extents = &fs_info->freed_extents[1];
6671 fs_info->pinned_extents = &fs_info->freed_extents[0];
6673 up_write(&fs_info->commit_root_sem);
6675 update_global_block_rsv(fs_info);
6679 * Returns the free cluster for the given space info and sets empty_cluster to
6680 * what it should be based on the mount options.
6682 static struct btrfs_free_cluster *
6683 fetch_cluster_info(struct btrfs_fs_info *fs_info,
6684 struct btrfs_space_info *space_info, u64 *empty_cluster)
6686 struct btrfs_free_cluster *ret = NULL;
6689 if (btrfs_mixed_space_info(space_info))
6692 if (space_info->flags & BTRFS_BLOCK_GROUP_METADATA) {
6693 ret = &fs_info->meta_alloc_cluster;
6694 if (btrfs_test_opt(fs_info, SSD))
6695 *empty_cluster = SZ_2M;
6697 *empty_cluster = SZ_64K;
6698 } else if ((space_info->flags & BTRFS_BLOCK_GROUP_DATA) &&
6699 btrfs_test_opt(fs_info, SSD_SPREAD)) {
6700 *empty_cluster = SZ_2M;
6701 ret = &fs_info->data_alloc_cluster;
6707 static int unpin_extent_range(struct btrfs_fs_info *fs_info,
6709 const bool return_free_space)
6711 struct btrfs_block_group_cache *cache = NULL;
6712 struct btrfs_space_info *space_info;
6713 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
6714 struct btrfs_free_cluster *cluster = NULL;
6716 u64 total_unpinned = 0;
6717 u64 empty_cluster = 0;
6720 while (start <= end) {
6723 start >= cache->key.objectid + cache->key.offset) {
6725 btrfs_put_block_group(cache);
6727 cache = btrfs_lookup_block_group(fs_info, start);
6728 BUG_ON(!cache); /* Logic error */
6730 cluster = fetch_cluster_info(fs_info,
6733 empty_cluster <<= 1;
6736 len = cache->key.objectid + cache->key.offset - start;
6737 len = min(len, end + 1 - start);
6739 if (start < cache->last_byte_to_unpin) {
6740 len = min(len, cache->last_byte_to_unpin - start);
6741 if (return_free_space)
6742 btrfs_add_free_space(cache, start, len);
6746 total_unpinned += len;
6747 space_info = cache->space_info;
6750 * If this space cluster has been marked as fragmented and we've
6751 * unpinned enough in this block group to potentially allow a
6752 * cluster to be created inside of it go ahead and clear the
6755 if (cluster && cluster->fragmented &&
6756 total_unpinned > empty_cluster) {
6757 spin_lock(&cluster->lock);
6758 cluster->fragmented = 0;
6759 spin_unlock(&cluster->lock);
6762 spin_lock(&space_info->lock);
6763 spin_lock(&cache->lock);
6764 cache->pinned -= len;
6765 space_info->bytes_pinned -= len;
6767 trace_btrfs_space_reservation(fs_info, "pinned",
6768 space_info->flags, len, 0);
6769 space_info->max_extent_size = 0;
6770 percpu_counter_add(&space_info->total_bytes_pinned, -len);
6772 space_info->bytes_readonly += len;
6775 spin_unlock(&cache->lock);
6776 if (!readonly && return_free_space &&
6777 global_rsv->space_info == space_info) {
6780 spin_lock(&global_rsv->lock);
6781 if (!global_rsv->full) {
6782 to_add = min(len, global_rsv->size -
6783 global_rsv->reserved);
6784 global_rsv->reserved += to_add;
6785 space_info->bytes_may_use += to_add;
6786 if (global_rsv->reserved >= global_rsv->size)
6787 global_rsv->full = 1;
6788 trace_btrfs_space_reservation(fs_info,
6794 spin_unlock(&global_rsv->lock);
6795 /* Add to any tickets we may have */
6797 space_info_add_new_bytes(fs_info, space_info,
6800 spin_unlock(&space_info->lock);
6804 btrfs_put_block_group(cache);
6808 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans)
6810 struct btrfs_fs_info *fs_info = trans->fs_info;
6811 struct btrfs_block_group_cache *block_group, *tmp;
6812 struct list_head *deleted_bgs;
6813 struct extent_io_tree *unpin;
6818 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
6819 unpin = &fs_info->freed_extents[1];
6821 unpin = &fs_info->freed_extents[0];
6823 while (!trans->aborted) {
6824 mutex_lock(&fs_info->unused_bg_unpin_mutex);
6825 ret = find_first_extent_bit(unpin, 0, &start, &end,
6826 EXTENT_DIRTY, NULL);
6828 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
6832 if (btrfs_test_opt(fs_info, DISCARD))
6833 ret = btrfs_discard_extent(fs_info, start,
6834 end + 1 - start, NULL);
6836 clear_extent_dirty(unpin, start, end);
6837 unpin_extent_range(fs_info, start, end, true);
6838 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
6843 * Transaction is finished. We don't need the lock anymore. We
6844 * do need to clean up the block groups in case of a transaction
6847 deleted_bgs = &trans->transaction->deleted_bgs;
6848 list_for_each_entry_safe(block_group, tmp, deleted_bgs, bg_list) {
6852 if (!trans->aborted)
6853 ret = btrfs_discard_extent(fs_info,
6854 block_group->key.objectid,
6855 block_group->key.offset,
6858 list_del_init(&block_group->bg_list);
6859 btrfs_put_block_group_trimming(block_group);
6860 btrfs_put_block_group(block_group);
6863 const char *errstr = btrfs_decode_error(ret);
6865 "discard failed while removing blockgroup: errno=%d %s",
6873 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
6874 struct btrfs_fs_info *info,
6875 struct btrfs_delayed_ref_node *node, u64 parent,
6876 u64 root_objectid, u64 owner_objectid,
6877 u64 owner_offset, int refs_to_drop,
6878 struct btrfs_delayed_extent_op *extent_op)
6880 struct btrfs_key key;
6881 struct btrfs_path *path;
6882 struct btrfs_root *extent_root = info->extent_root;
6883 struct extent_buffer *leaf;
6884 struct btrfs_extent_item *ei;
6885 struct btrfs_extent_inline_ref *iref;
6888 int extent_slot = 0;
6889 int found_extent = 0;
6893 u64 bytenr = node->bytenr;
6894 u64 num_bytes = node->num_bytes;
6896 bool skinny_metadata = btrfs_fs_incompat(info, SKINNY_METADATA);
6898 path = btrfs_alloc_path();
6902 path->reada = READA_FORWARD;
6903 path->leave_spinning = 1;
6905 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
6906 BUG_ON(!is_data && refs_to_drop != 1);
6909 skinny_metadata = false;
6911 ret = lookup_extent_backref(trans, info, path, &iref,
6912 bytenr, num_bytes, parent,
6913 root_objectid, owner_objectid,
6916 extent_slot = path->slots[0];
6917 while (extent_slot >= 0) {
6918 btrfs_item_key_to_cpu(path->nodes[0], &key,
6920 if (key.objectid != bytenr)
6922 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
6923 key.offset == num_bytes) {
6927 if (key.type == BTRFS_METADATA_ITEM_KEY &&
6928 key.offset == owner_objectid) {
6932 if (path->slots[0] - extent_slot > 5)
6936 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
6937 item_size = btrfs_item_size_nr(path->nodes[0], extent_slot);
6938 if (found_extent && item_size < sizeof(*ei))
6941 if (!found_extent) {
6943 ret = remove_extent_backref(trans, info, path, NULL,
6945 is_data, &last_ref);
6947 btrfs_abort_transaction(trans, ret);
6950 btrfs_release_path(path);
6951 path->leave_spinning = 1;
6953 key.objectid = bytenr;
6954 key.type = BTRFS_EXTENT_ITEM_KEY;
6955 key.offset = num_bytes;
6957 if (!is_data && skinny_metadata) {
6958 key.type = BTRFS_METADATA_ITEM_KEY;
6959 key.offset = owner_objectid;
6962 ret = btrfs_search_slot(trans, extent_root,
6964 if (ret > 0 && skinny_metadata && path->slots[0]) {
6966 * Couldn't find our skinny metadata item,
6967 * see if we have ye olde extent item.
6970 btrfs_item_key_to_cpu(path->nodes[0], &key,
6972 if (key.objectid == bytenr &&
6973 key.type == BTRFS_EXTENT_ITEM_KEY &&
6974 key.offset == num_bytes)
6978 if (ret > 0 && skinny_metadata) {
6979 skinny_metadata = false;
6980 key.objectid = bytenr;
6981 key.type = BTRFS_EXTENT_ITEM_KEY;
6982 key.offset = num_bytes;
6983 btrfs_release_path(path);
6984 ret = btrfs_search_slot(trans, extent_root,
6990 "umm, got %d back from search, was looking for %llu",
6993 btrfs_print_leaf(path->nodes[0]);
6996 btrfs_abort_transaction(trans, ret);
6999 extent_slot = path->slots[0];
7001 } else if (WARN_ON(ret == -ENOENT)) {
7002 btrfs_print_leaf(path->nodes[0]);
7004 "unable to find ref byte nr %llu parent %llu root %llu owner %llu offset %llu",
7005 bytenr, parent, root_objectid, owner_objectid,
7007 btrfs_abort_transaction(trans, ret);
7010 btrfs_abort_transaction(trans, ret);
7014 leaf = path->nodes[0];
7015 item_size = btrfs_item_size_nr(leaf, extent_slot);
7016 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
7017 if (item_size < sizeof(*ei)) {
7018 BUG_ON(found_extent || extent_slot != path->slots[0]);
7019 ret = convert_extent_item_v0(trans, info, path, owner_objectid,
7022 btrfs_abort_transaction(trans, ret);
7026 btrfs_release_path(path);
7027 path->leave_spinning = 1;
7029 key.objectid = bytenr;
7030 key.type = BTRFS_EXTENT_ITEM_KEY;
7031 key.offset = num_bytes;
7033 ret = btrfs_search_slot(trans, extent_root, &key, path,
7037 "umm, got %d back from search, was looking for %llu",
7039 btrfs_print_leaf(path->nodes[0]);
7042 btrfs_abort_transaction(trans, ret);
7046 extent_slot = path->slots[0];
7047 leaf = path->nodes[0];
7048 item_size = btrfs_item_size_nr(leaf, extent_slot);
7051 BUG_ON(item_size < sizeof(*ei));
7052 ei = btrfs_item_ptr(leaf, extent_slot,
7053 struct btrfs_extent_item);
7054 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID &&
7055 key.type == BTRFS_EXTENT_ITEM_KEY) {
7056 struct btrfs_tree_block_info *bi;
7057 BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
7058 bi = (struct btrfs_tree_block_info *)(ei + 1);
7059 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
7062 refs = btrfs_extent_refs(leaf, ei);
7063 if (refs < refs_to_drop) {
7065 "trying to drop %d refs but we only have %Lu for bytenr %Lu",
7066 refs_to_drop, refs, bytenr);
7068 btrfs_abort_transaction(trans, ret);
7071 refs -= refs_to_drop;
7075 __run_delayed_extent_op(extent_op, leaf, ei);
7077 * In the case of inline back ref, reference count will
7078 * be updated by remove_extent_backref
7081 BUG_ON(!found_extent);
7083 btrfs_set_extent_refs(leaf, ei, refs);
7084 btrfs_mark_buffer_dirty(leaf);
7087 ret = remove_extent_backref(trans, info, path,
7089 is_data, &last_ref);
7091 btrfs_abort_transaction(trans, ret);
7097 BUG_ON(is_data && refs_to_drop !=
7098 extent_data_ref_count(path, iref));
7100 BUG_ON(path->slots[0] != extent_slot);
7102 BUG_ON(path->slots[0] != extent_slot + 1);
7103 path->slots[0] = extent_slot;
7109 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
7112 btrfs_abort_transaction(trans, ret);
7115 btrfs_release_path(path);
7118 ret = btrfs_del_csums(trans, info, bytenr, num_bytes);
7120 btrfs_abort_transaction(trans, ret);
7125 ret = add_to_free_space_tree(trans, info, bytenr, num_bytes);
7127 btrfs_abort_transaction(trans, ret);
7131 ret = update_block_group(trans, info, bytenr, num_bytes, 0);
7133 btrfs_abort_transaction(trans, ret);
7137 btrfs_release_path(path);
7140 btrfs_free_path(path);
7145 * when we free an block, it is possible (and likely) that we free the last
7146 * delayed ref for that extent as well. This searches the delayed ref tree for
7147 * a given extent, and if there are no other delayed refs to be processed, it
7148 * removes it from the tree.
7150 static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans,
7153 struct btrfs_delayed_ref_head *head;
7154 struct btrfs_delayed_ref_root *delayed_refs;
7157 delayed_refs = &trans->transaction->delayed_refs;
7158 spin_lock(&delayed_refs->lock);
7159 head = btrfs_find_delayed_ref_head(delayed_refs, bytenr);
7161 goto out_delayed_unlock;
7163 spin_lock(&head->lock);
7164 if (!RB_EMPTY_ROOT(&head->ref_tree))
7167 if (head->extent_op) {
7168 if (!head->must_insert_reserved)
7170 btrfs_free_delayed_extent_op(head->extent_op);
7171 head->extent_op = NULL;
7175 * waiting for the lock here would deadlock. If someone else has it
7176 * locked they are already in the process of dropping it anyway
7178 if (!mutex_trylock(&head->mutex))
7182 * at this point we have a head with no other entries. Go
7183 * ahead and process it.
7185 rb_erase(&head->href_node, &delayed_refs->href_root);
7186 RB_CLEAR_NODE(&head->href_node);
7187 atomic_dec(&delayed_refs->num_entries);
7190 * we don't take a ref on the node because we're removing it from the
7191 * tree, so we just steal the ref the tree was holding.
7193 delayed_refs->num_heads--;
7194 if (head->processing == 0)
7195 delayed_refs->num_heads_ready--;
7196 head->processing = 0;
7197 spin_unlock(&head->lock);
7198 spin_unlock(&delayed_refs->lock);
7200 BUG_ON(head->extent_op);
7201 if (head->must_insert_reserved)
7204 mutex_unlock(&head->mutex);
7205 btrfs_put_delayed_ref_head(head);
7208 spin_unlock(&head->lock);
7211 spin_unlock(&delayed_refs->lock);
7215 void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
7216 struct btrfs_root *root,
7217 struct extent_buffer *buf,
7218 u64 parent, int last_ref)
7220 struct btrfs_fs_info *fs_info = root->fs_info;
7224 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
7225 int old_ref_mod, new_ref_mod;
7227 btrfs_ref_tree_mod(root, buf->start, buf->len, parent,
7228 root->root_key.objectid,
7229 btrfs_header_level(buf), 0,
7230 BTRFS_DROP_DELAYED_REF);
7231 ret = btrfs_add_delayed_tree_ref(fs_info, trans, buf->start,
7233 root->root_key.objectid,
7234 btrfs_header_level(buf),
7235 BTRFS_DROP_DELAYED_REF, NULL,
7236 &old_ref_mod, &new_ref_mod);
7237 BUG_ON(ret); /* -ENOMEM */
7238 pin = old_ref_mod >= 0 && new_ref_mod < 0;
7241 if (last_ref && btrfs_header_generation(buf) == trans->transid) {
7242 struct btrfs_block_group_cache *cache;
7244 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
7245 ret = check_ref_cleanup(trans, buf->start);
7251 cache = btrfs_lookup_block_group(fs_info, buf->start);
7253 if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
7254 pin_down_extent(fs_info, cache, buf->start,
7256 btrfs_put_block_group(cache);
7260 WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags));
7262 btrfs_add_free_space(cache, buf->start, buf->len);
7263 btrfs_free_reserved_bytes(cache, buf->len, 0);
7264 btrfs_put_block_group(cache);
7265 trace_btrfs_reserved_extent_free(fs_info, buf->start, buf->len);
7269 add_pinned_bytes(fs_info, buf->len, btrfs_header_level(buf),
7270 root->root_key.objectid);
7274 * Deleting the buffer, clear the corrupt flag since it doesn't
7277 clear_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags);
7281 /* Can return -ENOMEM */
7282 int btrfs_free_extent(struct btrfs_trans_handle *trans,
7283 struct btrfs_root *root,
7284 u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid,
7285 u64 owner, u64 offset)
7287 struct btrfs_fs_info *fs_info = root->fs_info;
7288 int old_ref_mod, new_ref_mod;
7291 if (btrfs_is_testing(fs_info))
7294 if (root_objectid != BTRFS_TREE_LOG_OBJECTID)
7295 btrfs_ref_tree_mod(root, bytenr, num_bytes, parent,
7296 root_objectid, owner, offset,
7297 BTRFS_DROP_DELAYED_REF);
7300 * tree log blocks never actually go into the extent allocation
7301 * tree, just update pinning info and exit early.
7303 if (root_objectid == BTRFS_TREE_LOG_OBJECTID) {
7304 WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID);
7305 /* unlocks the pinned mutex */
7306 btrfs_pin_extent(fs_info, bytenr, num_bytes, 1);
7307 old_ref_mod = new_ref_mod = 0;
7309 } else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
7310 ret = btrfs_add_delayed_tree_ref(fs_info, trans, bytenr,
7312 root_objectid, (int)owner,
7313 BTRFS_DROP_DELAYED_REF, NULL,
7314 &old_ref_mod, &new_ref_mod);
7316 ret = btrfs_add_delayed_data_ref(fs_info, trans, bytenr,
7318 root_objectid, owner, offset,
7319 0, BTRFS_DROP_DELAYED_REF,
7320 &old_ref_mod, &new_ref_mod);
7323 if (ret == 0 && old_ref_mod >= 0 && new_ref_mod < 0)
7324 add_pinned_bytes(fs_info, num_bytes, owner, root_objectid);
7330 * when we wait for progress in the block group caching, its because
7331 * our allocation attempt failed at least once. So, we must sleep
7332 * and let some progress happen before we try again.
7334 * This function will sleep at least once waiting for new free space to
7335 * show up, and then it will check the block group free space numbers
7336 * for our min num_bytes. Another option is to have it go ahead
7337 * and look in the rbtree for a free extent of a given size, but this
7340 * Callers of this must check if cache->cached == BTRFS_CACHE_ERROR before using
7341 * any of the information in this block group.
7343 static noinline void
7344 wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
7347 struct btrfs_caching_control *caching_ctl;
7349 caching_ctl = get_caching_control(cache);
7353 wait_event(caching_ctl->wait, block_group_cache_done(cache) ||
7354 (cache->free_space_ctl->free_space >= num_bytes));
7356 put_caching_control(caching_ctl);
7360 wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
7362 struct btrfs_caching_control *caching_ctl;
7365 caching_ctl = get_caching_control(cache);
7367 return (cache->cached == BTRFS_CACHE_ERROR) ? -EIO : 0;
7369 wait_event(caching_ctl->wait, block_group_cache_done(cache));
7370 if (cache->cached == BTRFS_CACHE_ERROR)
7372 put_caching_control(caching_ctl);
7376 static const char *btrfs_raid_type_names[BTRFS_NR_RAID_TYPES] = {
7377 [BTRFS_RAID_RAID10] = "raid10",
7378 [BTRFS_RAID_RAID1] = "raid1",
7379 [BTRFS_RAID_DUP] = "dup",
7380 [BTRFS_RAID_RAID0] = "raid0",
7381 [BTRFS_RAID_SINGLE] = "single",
7382 [BTRFS_RAID_RAID5] = "raid5",
7383 [BTRFS_RAID_RAID6] = "raid6",
7386 static const char *get_raid_name(enum btrfs_raid_types type)
7388 if (type >= BTRFS_NR_RAID_TYPES)
7391 return btrfs_raid_type_names[type];
7394 enum btrfs_loop_type {
7395 LOOP_CACHING_NOWAIT = 0,
7396 LOOP_CACHING_WAIT = 1,
7397 LOOP_ALLOC_CHUNK = 2,
7398 LOOP_NO_EMPTY_SIZE = 3,
7402 btrfs_lock_block_group(struct btrfs_block_group_cache *cache,
7406 down_read(&cache->data_rwsem);
7410 btrfs_grab_block_group(struct btrfs_block_group_cache *cache,
7413 btrfs_get_block_group(cache);
7415 down_read(&cache->data_rwsem);
7418 static struct btrfs_block_group_cache *
7419 btrfs_lock_cluster(struct btrfs_block_group_cache *block_group,
7420 struct btrfs_free_cluster *cluster,
7423 struct btrfs_block_group_cache *used_bg = NULL;
7425 spin_lock(&cluster->refill_lock);
7427 used_bg = cluster->block_group;
7431 if (used_bg == block_group)
7434 btrfs_get_block_group(used_bg);
7439 if (down_read_trylock(&used_bg->data_rwsem))
7442 spin_unlock(&cluster->refill_lock);
7444 /* We should only have one-level nested. */
7445 down_read_nested(&used_bg->data_rwsem, SINGLE_DEPTH_NESTING);
7447 spin_lock(&cluster->refill_lock);
7448 if (used_bg == cluster->block_group)
7451 up_read(&used_bg->data_rwsem);
7452 btrfs_put_block_group(used_bg);
7457 btrfs_release_block_group(struct btrfs_block_group_cache *cache,
7461 up_read(&cache->data_rwsem);
7462 btrfs_put_block_group(cache);
7466 * walks the btree of allocated extents and find a hole of a given size.
7467 * The key ins is changed to record the hole:
7468 * ins->objectid == start position
7469 * ins->flags = BTRFS_EXTENT_ITEM_KEY
7470 * ins->offset == the size of the hole.
7471 * Any available blocks before search_start are skipped.
7473 * If there is no suitable free space, we will record the max size of
7474 * the free space extent currently.
7476 static noinline int find_free_extent(struct btrfs_fs_info *fs_info,
7477 u64 ram_bytes, u64 num_bytes, u64 empty_size,
7478 u64 hint_byte, struct btrfs_key *ins,
7479 u64 flags, int delalloc)
7482 struct btrfs_root *root = fs_info->extent_root;
7483 struct btrfs_free_cluster *last_ptr = NULL;
7484 struct btrfs_block_group_cache *block_group = NULL;
7485 u64 search_start = 0;
7486 u64 max_extent_size = 0;
7487 u64 empty_cluster = 0;
7488 struct btrfs_space_info *space_info;
7490 int index = btrfs_bg_flags_to_raid_index(flags);
7491 bool failed_cluster_refill = false;
7492 bool failed_alloc = false;
7493 bool use_cluster = true;
7494 bool have_caching_bg = false;
7495 bool orig_have_caching_bg = false;
7496 bool full_search = false;
7498 WARN_ON(num_bytes < fs_info->sectorsize);
7499 ins->type = BTRFS_EXTENT_ITEM_KEY;
7503 trace_find_free_extent(fs_info, num_bytes, empty_size, flags);
7505 space_info = __find_space_info(fs_info, flags);
7507 btrfs_err(fs_info, "No space info for %llu", flags);
7512 * If our free space is heavily fragmented we may not be able to make
7513 * big contiguous allocations, so instead of doing the expensive search
7514 * for free space, simply return ENOSPC with our max_extent_size so we
7515 * can go ahead and search for a more manageable chunk.
7517 * If our max_extent_size is large enough for our allocation simply
7518 * disable clustering since we will likely not be able to find enough
7519 * space to create a cluster and induce latency trying.
7521 if (unlikely(space_info->max_extent_size)) {
7522 spin_lock(&space_info->lock);
7523 if (space_info->max_extent_size &&
7524 num_bytes > space_info->max_extent_size) {
7525 ins->offset = space_info->max_extent_size;
7526 spin_unlock(&space_info->lock);
7528 } else if (space_info->max_extent_size) {
7529 use_cluster = false;
7531 spin_unlock(&space_info->lock);
7534 last_ptr = fetch_cluster_info(fs_info, space_info, &empty_cluster);
7536 spin_lock(&last_ptr->lock);
7537 if (last_ptr->block_group)
7538 hint_byte = last_ptr->window_start;
7539 if (last_ptr->fragmented) {
7541 * We still set window_start so we can keep track of the
7542 * last place we found an allocation to try and save
7545 hint_byte = last_ptr->window_start;
7546 use_cluster = false;
7548 spin_unlock(&last_ptr->lock);
7551 search_start = max(search_start, first_logical_byte(fs_info, 0));
7552 search_start = max(search_start, hint_byte);
7553 if (search_start == hint_byte) {
7554 block_group = btrfs_lookup_block_group(fs_info, search_start);
7556 * we don't want to use the block group if it doesn't match our
7557 * allocation bits, or if its not cached.
7559 * However if we are re-searching with an ideal block group
7560 * picked out then we don't care that the block group is cached.
7562 if (block_group && block_group_bits(block_group, flags) &&
7563 block_group->cached != BTRFS_CACHE_NO) {
7564 down_read(&space_info->groups_sem);
7565 if (list_empty(&block_group->list) ||
7568 * someone is removing this block group,
7569 * we can't jump into the have_block_group
7570 * target because our list pointers are not
7573 btrfs_put_block_group(block_group);
7574 up_read(&space_info->groups_sem);
7576 index = btrfs_bg_flags_to_raid_index(
7577 block_group->flags);
7578 btrfs_lock_block_group(block_group, delalloc);
7579 goto have_block_group;
7581 } else if (block_group) {
7582 btrfs_put_block_group(block_group);
7586 have_caching_bg = false;
7587 if (index == 0 || index == btrfs_bg_flags_to_raid_index(flags))
7589 down_read(&space_info->groups_sem);
7590 list_for_each_entry(block_group, &space_info->block_groups[index],
7595 /* If the block group is read-only, we can skip it entirely. */
7596 if (unlikely(block_group->ro))
7599 btrfs_grab_block_group(block_group, delalloc);
7600 search_start = block_group->key.objectid;
7603 * this can happen if we end up cycling through all the
7604 * raid types, but we want to make sure we only allocate
7605 * for the proper type.
7607 if (!block_group_bits(block_group, flags)) {
7608 u64 extra = BTRFS_BLOCK_GROUP_DUP |
7609 BTRFS_BLOCK_GROUP_RAID1 |
7610 BTRFS_BLOCK_GROUP_RAID5 |
7611 BTRFS_BLOCK_GROUP_RAID6 |
7612 BTRFS_BLOCK_GROUP_RAID10;
7615 * if they asked for extra copies and this block group
7616 * doesn't provide them, bail. This does allow us to
7617 * fill raid0 from raid1.
7619 if ((flags & extra) && !(block_group->flags & extra))
7624 cached = block_group_cache_done(block_group);
7625 if (unlikely(!cached)) {
7626 have_caching_bg = true;
7627 ret = cache_block_group(block_group, 0);
7632 if (unlikely(block_group->cached == BTRFS_CACHE_ERROR))
7636 * Ok we want to try and use the cluster allocator, so
7639 if (last_ptr && use_cluster) {
7640 struct btrfs_block_group_cache *used_block_group;
7641 unsigned long aligned_cluster;
7643 * the refill lock keeps out other
7644 * people trying to start a new cluster
7646 used_block_group = btrfs_lock_cluster(block_group,
7649 if (!used_block_group)
7650 goto refill_cluster;
7652 if (used_block_group != block_group &&
7653 (used_block_group->ro ||
7654 !block_group_bits(used_block_group, flags)))
7655 goto release_cluster;
7657 offset = btrfs_alloc_from_cluster(used_block_group,
7660 used_block_group->key.objectid,
7663 /* we have a block, we're done */
7664 spin_unlock(&last_ptr->refill_lock);
7665 trace_btrfs_reserve_extent_cluster(fs_info,
7667 search_start, num_bytes);
7668 if (used_block_group != block_group) {
7669 btrfs_release_block_group(block_group,
7671 block_group = used_block_group;
7676 WARN_ON(last_ptr->block_group != used_block_group);
7678 /* If we are on LOOP_NO_EMPTY_SIZE, we can't
7679 * set up a new clusters, so lets just skip it
7680 * and let the allocator find whatever block
7681 * it can find. If we reach this point, we
7682 * will have tried the cluster allocator
7683 * plenty of times and not have found
7684 * anything, so we are likely way too
7685 * fragmented for the clustering stuff to find
7688 * However, if the cluster is taken from the
7689 * current block group, release the cluster
7690 * first, so that we stand a better chance of
7691 * succeeding in the unclustered
7693 if (loop >= LOOP_NO_EMPTY_SIZE &&
7694 used_block_group != block_group) {
7695 spin_unlock(&last_ptr->refill_lock);
7696 btrfs_release_block_group(used_block_group,
7698 goto unclustered_alloc;
7702 * this cluster didn't work out, free it and
7705 btrfs_return_cluster_to_free_space(NULL, last_ptr);
7707 if (used_block_group != block_group)
7708 btrfs_release_block_group(used_block_group,
7711 if (loop >= LOOP_NO_EMPTY_SIZE) {
7712 spin_unlock(&last_ptr->refill_lock);
7713 goto unclustered_alloc;
7716 aligned_cluster = max_t(unsigned long,
7717 empty_cluster + empty_size,
7718 block_group->full_stripe_len);
7720 /* allocate a cluster in this block group */
7721 ret = btrfs_find_space_cluster(fs_info, block_group,
7722 last_ptr, search_start,
7727 * now pull our allocation out of this
7730 offset = btrfs_alloc_from_cluster(block_group,
7736 /* we found one, proceed */
7737 spin_unlock(&last_ptr->refill_lock);
7738 trace_btrfs_reserve_extent_cluster(fs_info,
7739 block_group, search_start,
7743 } else if (!cached && loop > LOOP_CACHING_NOWAIT
7744 && !failed_cluster_refill) {
7745 spin_unlock(&last_ptr->refill_lock);
7747 failed_cluster_refill = true;
7748 wait_block_group_cache_progress(block_group,
7749 num_bytes + empty_cluster + empty_size);
7750 goto have_block_group;
7754 * at this point we either didn't find a cluster
7755 * or we weren't able to allocate a block from our
7756 * cluster. Free the cluster we've been trying
7757 * to use, and go to the next block group
7759 btrfs_return_cluster_to_free_space(NULL, last_ptr);
7760 spin_unlock(&last_ptr->refill_lock);
7766 * We are doing an unclustered alloc, set the fragmented flag so
7767 * we don't bother trying to setup a cluster again until we get
7770 if (unlikely(last_ptr)) {
7771 spin_lock(&last_ptr->lock);
7772 last_ptr->fragmented = 1;
7773 spin_unlock(&last_ptr->lock);
7776 struct btrfs_free_space_ctl *ctl =
7777 block_group->free_space_ctl;
7779 spin_lock(&ctl->tree_lock);
7780 if (ctl->free_space <
7781 num_bytes + empty_cluster + empty_size) {
7782 if (ctl->free_space > max_extent_size)
7783 max_extent_size = ctl->free_space;
7784 spin_unlock(&ctl->tree_lock);
7787 spin_unlock(&ctl->tree_lock);
7790 offset = btrfs_find_space_for_alloc(block_group, search_start,
7791 num_bytes, empty_size,
7794 * If we didn't find a chunk, and we haven't failed on this
7795 * block group before, and this block group is in the middle of
7796 * caching and we are ok with waiting, then go ahead and wait
7797 * for progress to be made, and set failed_alloc to true.
7799 * If failed_alloc is true then we've already waited on this
7800 * block group once and should move on to the next block group.
7802 if (!offset && !failed_alloc && !cached &&
7803 loop > LOOP_CACHING_NOWAIT) {
7804 wait_block_group_cache_progress(block_group,
7805 num_bytes + empty_size);
7806 failed_alloc = true;
7807 goto have_block_group;
7808 } else if (!offset) {
7812 search_start = ALIGN(offset, fs_info->stripesize);
7814 /* move on to the next group */
7815 if (search_start + num_bytes >
7816 block_group->key.objectid + block_group->key.offset) {
7817 btrfs_add_free_space(block_group, offset, num_bytes);
7821 if (offset < search_start)
7822 btrfs_add_free_space(block_group, offset,
7823 search_start - offset);
7824 BUG_ON(offset > search_start);
7826 ret = btrfs_add_reserved_bytes(block_group, ram_bytes,
7827 num_bytes, delalloc);
7828 if (ret == -EAGAIN) {
7829 btrfs_add_free_space(block_group, offset, num_bytes);
7832 btrfs_inc_block_group_reservations(block_group);
7834 /* we are all good, lets return */
7835 ins->objectid = search_start;
7836 ins->offset = num_bytes;
7838 trace_btrfs_reserve_extent(fs_info, block_group,
7839 search_start, num_bytes);
7840 btrfs_release_block_group(block_group, delalloc);
7843 failed_cluster_refill = false;
7844 failed_alloc = false;
7845 BUG_ON(btrfs_bg_flags_to_raid_index(block_group->flags) !=
7847 btrfs_release_block_group(block_group, delalloc);
7850 up_read(&space_info->groups_sem);
7852 if ((loop == LOOP_CACHING_NOWAIT) && have_caching_bg
7853 && !orig_have_caching_bg)
7854 orig_have_caching_bg = true;
7856 if (!ins->objectid && loop >= LOOP_CACHING_WAIT && have_caching_bg)
7859 if (!ins->objectid && ++index < BTRFS_NR_RAID_TYPES)
7863 * LOOP_CACHING_NOWAIT, search partially cached block groups, kicking
7864 * caching kthreads as we move along
7865 * LOOP_CACHING_WAIT, search everything, and wait if our bg is caching
7866 * LOOP_ALLOC_CHUNK, force a chunk allocation and try again
7867 * LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try
7870 if (!ins->objectid && loop < LOOP_NO_EMPTY_SIZE) {
7872 if (loop == LOOP_CACHING_NOWAIT) {
7874 * We want to skip the LOOP_CACHING_WAIT step if we
7875 * don't have any uncached bgs and we've already done a
7876 * full search through.
7878 if (orig_have_caching_bg || !full_search)
7879 loop = LOOP_CACHING_WAIT;
7881 loop = LOOP_ALLOC_CHUNK;
7886 if (loop == LOOP_ALLOC_CHUNK) {
7887 struct btrfs_trans_handle *trans;
7890 trans = current->journal_info;
7894 trans = btrfs_join_transaction(root);
7896 if (IS_ERR(trans)) {
7897 ret = PTR_ERR(trans);
7901 ret = do_chunk_alloc(trans, fs_info, flags,
7905 * If we can't allocate a new chunk we've already looped
7906 * through at least once, move on to the NO_EMPTY_SIZE
7910 loop = LOOP_NO_EMPTY_SIZE;
7913 * Do not bail out on ENOSPC since we
7914 * can do more things.
7916 if (ret < 0 && ret != -ENOSPC)
7917 btrfs_abort_transaction(trans, ret);
7921 btrfs_end_transaction(trans);
7926 if (loop == LOOP_NO_EMPTY_SIZE) {
7928 * Don't loop again if we already have no empty_size and
7931 if (empty_size == 0 &&
7932 empty_cluster == 0) {
7941 } else if (!ins->objectid) {
7943 } else if (ins->objectid) {
7944 if (!use_cluster && last_ptr) {
7945 spin_lock(&last_ptr->lock);
7946 last_ptr->window_start = ins->objectid;
7947 spin_unlock(&last_ptr->lock);
7952 if (ret == -ENOSPC) {
7953 spin_lock(&space_info->lock);
7954 space_info->max_extent_size = max_extent_size;
7955 spin_unlock(&space_info->lock);
7956 ins->offset = max_extent_size;
7961 static void dump_space_info(struct btrfs_fs_info *fs_info,
7962 struct btrfs_space_info *info, u64 bytes,
7963 int dump_block_groups)
7965 struct btrfs_block_group_cache *cache;
7968 spin_lock(&info->lock);
7969 btrfs_info(fs_info, "space_info %llu has %llu free, is %sfull",
7971 info->total_bytes - btrfs_space_info_used(info, true),
7972 info->full ? "" : "not ");
7974 "space_info total=%llu, used=%llu, pinned=%llu, reserved=%llu, may_use=%llu, readonly=%llu",
7975 info->total_bytes, info->bytes_used, info->bytes_pinned,
7976 info->bytes_reserved, info->bytes_may_use,
7977 info->bytes_readonly);
7978 spin_unlock(&info->lock);
7980 if (!dump_block_groups)
7983 down_read(&info->groups_sem);
7985 list_for_each_entry(cache, &info->block_groups[index], list) {
7986 spin_lock(&cache->lock);
7988 "block group %llu has %llu bytes, %llu used %llu pinned %llu reserved %s",
7989 cache->key.objectid, cache->key.offset,
7990 btrfs_block_group_used(&cache->item), cache->pinned,
7991 cache->reserved, cache->ro ? "[readonly]" : "");
7992 btrfs_dump_free_space(cache, bytes);
7993 spin_unlock(&cache->lock);
7995 if (++index < BTRFS_NR_RAID_TYPES)
7997 up_read(&info->groups_sem);
8001 * btrfs_reserve_extent - entry point to the extent allocator. Tries to find a
8002 * hole that is at least as big as @num_bytes.
8004 * @root - The root that will contain this extent
8006 * @ram_bytes - The amount of space in ram that @num_bytes take. This
8007 * is used for accounting purposes. This value differs
8008 * from @num_bytes only in the case of compressed extents.
8010 * @num_bytes - Number of bytes to allocate on-disk.
8012 * @min_alloc_size - Indicates the minimum amount of space that the
8013 * allocator should try to satisfy. In some cases
8014 * @num_bytes may be larger than what is required and if
8015 * the filesystem is fragmented then allocation fails.
8016 * However, the presence of @min_alloc_size gives a
8017 * chance to try and satisfy the smaller allocation.
8019 * @empty_size - A hint that you plan on doing more COW. This is the
8020 * size in bytes the allocator should try to find free
8021 * next to the block it returns. This is just a hint and
8022 * may be ignored by the allocator.
8024 * @hint_byte - Hint to the allocator to start searching above the byte
8025 * address passed. It might be ignored.
8027 * @ins - This key is modified to record the found hole. It will
8028 * have the following values:
8029 * ins->objectid == start position
8030 * ins->flags = BTRFS_EXTENT_ITEM_KEY
8031 * ins->offset == the size of the hole.
8033 * @is_data - Boolean flag indicating whether an extent is
8034 * allocated for data (true) or metadata (false)
8036 * @delalloc - Boolean flag indicating whether this allocation is for
8037 * delalloc or not. If 'true' data_rwsem of block groups
8038 * is going to be acquired.
8041 * Returns 0 when an allocation succeeded or < 0 when an error occurred. In
8042 * case -ENOSPC is returned then @ins->offset will contain the size of the
8043 * largest available hole the allocator managed to find.
8045 int btrfs_reserve_extent(struct btrfs_root *root, u64 ram_bytes,
8046 u64 num_bytes, u64 min_alloc_size,
8047 u64 empty_size, u64 hint_byte,
8048 struct btrfs_key *ins, int is_data, int delalloc)
8050 struct btrfs_fs_info *fs_info = root->fs_info;
8051 bool final_tried = num_bytes == min_alloc_size;
8055 flags = get_alloc_profile_by_root(root, is_data);
8057 WARN_ON(num_bytes < fs_info->sectorsize);
8058 ret = find_free_extent(fs_info, ram_bytes, num_bytes, empty_size,
8059 hint_byte, ins, flags, delalloc);
8060 if (!ret && !is_data) {
8061 btrfs_dec_block_group_reservations(fs_info, ins->objectid);
8062 } else if (ret == -ENOSPC) {
8063 if (!final_tried && ins->offset) {
8064 num_bytes = min(num_bytes >> 1, ins->offset);
8065 num_bytes = round_down(num_bytes,
8066 fs_info->sectorsize);
8067 num_bytes = max(num_bytes, min_alloc_size);
8068 ram_bytes = num_bytes;
8069 if (num_bytes == min_alloc_size)
8072 } else if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
8073 struct btrfs_space_info *sinfo;
8075 sinfo = __find_space_info(fs_info, flags);
8077 "allocation failed flags %llu, wanted %llu",
8080 dump_space_info(fs_info, sinfo, num_bytes, 1);
8087 static int __btrfs_free_reserved_extent(struct btrfs_fs_info *fs_info,
8089 int pin, int delalloc)
8091 struct btrfs_block_group_cache *cache;
8094 cache = btrfs_lookup_block_group(fs_info, start);
8096 btrfs_err(fs_info, "Unable to find block group for %llu",
8102 pin_down_extent(fs_info, cache, start, len, 1);
8104 if (btrfs_test_opt(fs_info, DISCARD))
8105 ret = btrfs_discard_extent(fs_info, start, len, NULL);
8106 btrfs_add_free_space(cache, start, len);
8107 btrfs_free_reserved_bytes(cache, len, delalloc);
8108 trace_btrfs_reserved_extent_free(fs_info, start, len);
8111 btrfs_put_block_group(cache);
8115 int btrfs_free_reserved_extent(struct btrfs_fs_info *fs_info,
8116 u64 start, u64 len, int delalloc)
8118 return __btrfs_free_reserved_extent(fs_info, start, len, 0, delalloc);
8121 int btrfs_free_and_pin_reserved_extent(struct btrfs_fs_info *fs_info,
8124 return __btrfs_free_reserved_extent(fs_info, start, len, 1, 0);
8127 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
8128 struct btrfs_fs_info *fs_info,
8129 u64 parent, u64 root_objectid,
8130 u64 flags, u64 owner, u64 offset,
8131 struct btrfs_key *ins, int ref_mod)
8134 struct btrfs_extent_item *extent_item;
8135 struct btrfs_extent_inline_ref *iref;
8136 struct btrfs_path *path;
8137 struct extent_buffer *leaf;
8142 type = BTRFS_SHARED_DATA_REF_KEY;
8144 type = BTRFS_EXTENT_DATA_REF_KEY;
8146 size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type);
8148 path = btrfs_alloc_path();
8152 path->leave_spinning = 1;
8153 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
8156 btrfs_free_path(path);
8160 leaf = path->nodes[0];
8161 extent_item = btrfs_item_ptr(leaf, path->slots[0],
8162 struct btrfs_extent_item);
8163 btrfs_set_extent_refs(leaf, extent_item, ref_mod);
8164 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
8165 btrfs_set_extent_flags(leaf, extent_item,
8166 flags | BTRFS_EXTENT_FLAG_DATA);
8168 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
8169 btrfs_set_extent_inline_ref_type(leaf, iref, type);
8171 struct btrfs_shared_data_ref *ref;
8172 ref = (struct btrfs_shared_data_ref *)(iref + 1);
8173 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
8174 btrfs_set_shared_data_ref_count(leaf, ref, ref_mod);
8176 struct btrfs_extent_data_ref *ref;
8177 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
8178 btrfs_set_extent_data_ref_root(leaf, ref, root_objectid);
8179 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
8180 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
8181 btrfs_set_extent_data_ref_count(leaf, ref, ref_mod);
8184 btrfs_mark_buffer_dirty(path->nodes[0]);
8185 btrfs_free_path(path);
8187 ret = remove_from_free_space_tree(trans, fs_info, ins->objectid,
8192 ret = update_block_group(trans, fs_info, ins->objectid, ins->offset, 1);
8193 if (ret) { /* -ENOENT, logic error */
8194 btrfs_err(fs_info, "update block group failed for %llu %llu",
8195 ins->objectid, ins->offset);
8198 trace_btrfs_reserved_extent_alloc(fs_info, ins->objectid, ins->offset);
8202 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
8203 struct btrfs_fs_info *fs_info,
8204 u64 parent, u64 root_objectid,
8205 u64 flags, struct btrfs_disk_key *key,
8206 int level, struct btrfs_key *ins)
8209 struct btrfs_extent_item *extent_item;
8210 struct btrfs_tree_block_info *block_info;
8211 struct btrfs_extent_inline_ref *iref;
8212 struct btrfs_path *path;
8213 struct extent_buffer *leaf;
8214 u32 size = sizeof(*extent_item) + sizeof(*iref);
8215 u64 num_bytes = ins->offset;
8216 bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
8218 if (!skinny_metadata)
8219 size += sizeof(*block_info);
8221 path = btrfs_alloc_path();
8223 btrfs_free_and_pin_reserved_extent(fs_info, ins->objectid,
8228 path->leave_spinning = 1;
8229 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
8232 btrfs_free_path(path);
8233 btrfs_free_and_pin_reserved_extent(fs_info, ins->objectid,
8238 leaf = path->nodes[0];
8239 extent_item = btrfs_item_ptr(leaf, path->slots[0],
8240 struct btrfs_extent_item);
8241 btrfs_set_extent_refs(leaf, extent_item, 1);
8242 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
8243 btrfs_set_extent_flags(leaf, extent_item,
8244 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
8246 if (skinny_metadata) {
8247 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
8248 num_bytes = fs_info->nodesize;
8250 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
8251 btrfs_set_tree_block_key(leaf, block_info, key);
8252 btrfs_set_tree_block_level(leaf, block_info, level);
8253 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
8257 BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF));
8258 btrfs_set_extent_inline_ref_type(leaf, iref,
8259 BTRFS_SHARED_BLOCK_REF_KEY);
8260 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
8262 btrfs_set_extent_inline_ref_type(leaf, iref,
8263 BTRFS_TREE_BLOCK_REF_KEY);
8264 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
8267 btrfs_mark_buffer_dirty(leaf);
8268 btrfs_free_path(path);
8270 ret = remove_from_free_space_tree(trans, fs_info, ins->objectid,
8275 ret = update_block_group(trans, fs_info, ins->objectid,
8276 fs_info->nodesize, 1);
8277 if (ret) { /* -ENOENT, logic error */
8278 btrfs_err(fs_info, "update block group failed for %llu %llu",
8279 ins->objectid, ins->offset);
8283 trace_btrfs_reserved_extent_alloc(fs_info, ins->objectid,
8288 int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
8289 struct btrfs_root *root, u64 owner,
8290 u64 offset, u64 ram_bytes,
8291 struct btrfs_key *ins)
8293 struct btrfs_fs_info *fs_info = root->fs_info;
8296 BUG_ON(root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID);
8298 btrfs_ref_tree_mod(root, ins->objectid, ins->offset, 0,
8299 root->root_key.objectid, owner, offset,
8300 BTRFS_ADD_DELAYED_EXTENT);
8302 ret = btrfs_add_delayed_data_ref(fs_info, trans, ins->objectid,
8304 root->root_key.objectid, owner,
8306 BTRFS_ADD_DELAYED_EXTENT, NULL, NULL);
8311 * this is used by the tree logging recovery code. It records that
8312 * an extent has been allocated and makes sure to clear the free
8313 * space cache bits as well
8315 int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
8316 struct btrfs_fs_info *fs_info,
8317 u64 root_objectid, u64 owner, u64 offset,
8318 struct btrfs_key *ins)
8321 struct btrfs_block_group_cache *block_group;
8322 struct btrfs_space_info *space_info;
8325 * Mixed block groups will exclude before processing the log so we only
8326 * need to do the exclude dance if this fs isn't mixed.
8328 if (!btrfs_fs_incompat(fs_info, MIXED_GROUPS)) {
8329 ret = __exclude_logged_extent(fs_info, ins->objectid,
8335 block_group = btrfs_lookup_block_group(fs_info, ins->objectid);
8339 space_info = block_group->space_info;
8340 spin_lock(&space_info->lock);
8341 spin_lock(&block_group->lock);
8342 space_info->bytes_reserved += ins->offset;
8343 block_group->reserved += ins->offset;
8344 spin_unlock(&block_group->lock);
8345 spin_unlock(&space_info->lock);
8347 ret = alloc_reserved_file_extent(trans, fs_info, 0, root_objectid,
8348 0, owner, offset, ins, 1);
8349 btrfs_put_block_group(block_group);
8353 static struct extent_buffer *
8354 btrfs_init_new_buffer(struct btrfs_trans_handle *trans, struct btrfs_root *root,
8355 u64 bytenr, int level)
8357 struct btrfs_fs_info *fs_info = root->fs_info;
8358 struct extent_buffer *buf;
8360 buf = btrfs_find_create_tree_block(fs_info, bytenr);
8364 btrfs_set_header_generation(buf, trans->transid);
8365 btrfs_set_buffer_lockdep_class(root->root_key.objectid, buf, level);
8366 btrfs_tree_lock(buf);
8367 clean_tree_block(fs_info, buf);
8368 clear_bit(EXTENT_BUFFER_STALE, &buf->bflags);
8370 btrfs_set_lock_blocking(buf);
8371 set_extent_buffer_uptodate(buf);
8373 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
8374 buf->log_index = root->log_transid % 2;
8376 * we allow two log transactions at a time, use different
8377 * EXENT bit to differentiate dirty pages.
8379 if (buf->log_index == 0)
8380 set_extent_dirty(&root->dirty_log_pages, buf->start,
8381 buf->start + buf->len - 1, GFP_NOFS);
8383 set_extent_new(&root->dirty_log_pages, buf->start,
8384 buf->start + buf->len - 1);
8386 buf->log_index = -1;
8387 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
8388 buf->start + buf->len - 1, GFP_NOFS);
8390 trans->dirty = true;
8391 /* this returns a buffer locked for blocking */
8395 static struct btrfs_block_rsv *
8396 use_block_rsv(struct btrfs_trans_handle *trans,
8397 struct btrfs_root *root, u32 blocksize)
8399 struct btrfs_fs_info *fs_info = root->fs_info;
8400 struct btrfs_block_rsv *block_rsv;
8401 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
8403 bool global_updated = false;
8405 block_rsv = get_block_rsv(trans, root);
8407 if (unlikely(block_rsv->size == 0))
8410 ret = block_rsv_use_bytes(block_rsv, blocksize);
8414 if (block_rsv->failfast)
8415 return ERR_PTR(ret);
8417 if (block_rsv->type == BTRFS_BLOCK_RSV_GLOBAL && !global_updated) {
8418 global_updated = true;
8419 update_global_block_rsv(fs_info);
8423 if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
8424 static DEFINE_RATELIMIT_STATE(_rs,
8425 DEFAULT_RATELIMIT_INTERVAL * 10,
8426 /*DEFAULT_RATELIMIT_BURST*/ 1);
8427 if (__ratelimit(&_rs))
8429 "BTRFS: block rsv returned %d\n", ret);
8432 ret = reserve_metadata_bytes(root, block_rsv, blocksize,
8433 BTRFS_RESERVE_NO_FLUSH);
8437 * If we couldn't reserve metadata bytes try and use some from
8438 * the global reserve if its space type is the same as the global
8441 if (block_rsv->type != BTRFS_BLOCK_RSV_GLOBAL &&
8442 block_rsv->space_info == global_rsv->space_info) {
8443 ret = block_rsv_use_bytes(global_rsv, blocksize);
8447 return ERR_PTR(ret);
8450 static void unuse_block_rsv(struct btrfs_fs_info *fs_info,
8451 struct btrfs_block_rsv *block_rsv, u32 blocksize)
8453 block_rsv_add_bytes(block_rsv, blocksize, 0);
8454 block_rsv_release_bytes(fs_info, block_rsv, NULL, 0, NULL);
8458 * finds a free extent and does all the dirty work required for allocation
8459 * returns the tree buffer or an ERR_PTR on error.
8461 struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans,
8462 struct btrfs_root *root,
8463 u64 parent, u64 root_objectid,
8464 const struct btrfs_disk_key *key,
8465 int level, u64 hint,
8468 struct btrfs_fs_info *fs_info = root->fs_info;
8469 struct btrfs_key ins;
8470 struct btrfs_block_rsv *block_rsv;
8471 struct extent_buffer *buf;
8472 struct btrfs_delayed_extent_op *extent_op;
8475 u32 blocksize = fs_info->nodesize;
8476 bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
8478 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
8479 if (btrfs_is_testing(fs_info)) {
8480 buf = btrfs_init_new_buffer(trans, root, root->alloc_bytenr,
8483 root->alloc_bytenr += blocksize;
8488 block_rsv = use_block_rsv(trans, root, blocksize);
8489 if (IS_ERR(block_rsv))
8490 return ERR_CAST(block_rsv);
8492 ret = btrfs_reserve_extent(root, blocksize, blocksize, blocksize,
8493 empty_size, hint, &ins, 0, 0);
8497 buf = btrfs_init_new_buffer(trans, root, ins.objectid, level);
8500 goto out_free_reserved;
8503 if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
8505 parent = ins.objectid;
8506 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
8510 if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
8511 extent_op = btrfs_alloc_delayed_extent_op();
8517 memcpy(&extent_op->key, key, sizeof(extent_op->key));
8519 memset(&extent_op->key, 0, sizeof(extent_op->key));
8520 extent_op->flags_to_set = flags;
8521 extent_op->update_key = skinny_metadata ? false : true;
8522 extent_op->update_flags = true;
8523 extent_op->is_data = false;
8524 extent_op->level = level;
8526 btrfs_ref_tree_mod(root, ins.objectid, ins.offset, parent,
8527 root_objectid, level, 0,
8528 BTRFS_ADD_DELAYED_EXTENT);
8529 ret = btrfs_add_delayed_tree_ref(fs_info, trans, ins.objectid,
8531 root_objectid, level,
8532 BTRFS_ADD_DELAYED_EXTENT,
8533 extent_op, NULL, NULL);
8535 goto out_free_delayed;
8540 btrfs_free_delayed_extent_op(extent_op);
8542 free_extent_buffer(buf);
8544 btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 0);
8546 unuse_block_rsv(fs_info, block_rsv, blocksize);
8547 return ERR_PTR(ret);
8550 struct walk_control {
8551 u64 refs[BTRFS_MAX_LEVEL];
8552 u64 flags[BTRFS_MAX_LEVEL];
8553 struct btrfs_key update_progress;
8564 #define DROP_REFERENCE 1
8565 #define UPDATE_BACKREF 2
8567 static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
8568 struct btrfs_root *root,
8569 struct walk_control *wc,
8570 struct btrfs_path *path)
8572 struct btrfs_fs_info *fs_info = root->fs_info;
8578 struct btrfs_key key;
8579 struct extent_buffer *eb;
8584 if (path->slots[wc->level] < wc->reada_slot) {
8585 wc->reada_count = wc->reada_count * 2 / 3;
8586 wc->reada_count = max(wc->reada_count, 2);
8588 wc->reada_count = wc->reada_count * 3 / 2;
8589 wc->reada_count = min_t(int, wc->reada_count,
8590 BTRFS_NODEPTRS_PER_BLOCK(fs_info));
8593 eb = path->nodes[wc->level];
8594 nritems = btrfs_header_nritems(eb);
8596 for (slot = path->slots[wc->level]; slot < nritems; slot++) {
8597 if (nread >= wc->reada_count)
8601 bytenr = btrfs_node_blockptr(eb, slot);
8602 generation = btrfs_node_ptr_generation(eb, slot);
8604 if (slot == path->slots[wc->level])
8607 if (wc->stage == UPDATE_BACKREF &&
8608 generation <= root->root_key.offset)
8611 /* We don't lock the tree block, it's OK to be racy here */
8612 ret = btrfs_lookup_extent_info(trans, fs_info, bytenr,
8613 wc->level - 1, 1, &refs,
8615 /* We don't care about errors in readahead. */
8620 if (wc->stage == DROP_REFERENCE) {
8624 if (wc->level == 1 &&
8625 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
8627 if (!wc->update_ref ||
8628 generation <= root->root_key.offset)
8630 btrfs_node_key_to_cpu(eb, &key, slot);
8631 ret = btrfs_comp_cpu_keys(&key,
8632 &wc->update_progress);
8636 if (wc->level == 1 &&
8637 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
8641 readahead_tree_block(fs_info, bytenr);
8644 wc->reada_slot = slot;
8648 * helper to process tree block while walking down the tree.
8650 * when wc->stage == UPDATE_BACKREF, this function updates
8651 * back refs for pointers in the block.
8653 * NOTE: return value 1 means we should stop walking down.
8655 static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
8656 struct btrfs_root *root,
8657 struct btrfs_path *path,
8658 struct walk_control *wc, int lookup_info)
8660 struct btrfs_fs_info *fs_info = root->fs_info;
8661 int level = wc->level;
8662 struct extent_buffer *eb = path->nodes[level];
8663 u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF;
8666 if (wc->stage == UPDATE_BACKREF &&
8667 btrfs_header_owner(eb) != root->root_key.objectid)
8671 * when reference count of tree block is 1, it won't increase
8672 * again. once full backref flag is set, we never clear it.
8675 ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
8676 (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag)))) {
8677 BUG_ON(!path->locks[level]);
8678 ret = btrfs_lookup_extent_info(trans, fs_info,
8679 eb->start, level, 1,
8682 BUG_ON(ret == -ENOMEM);
8685 BUG_ON(wc->refs[level] == 0);
8688 if (wc->stage == DROP_REFERENCE) {
8689 if (wc->refs[level] > 1)
8692 if (path->locks[level] && !wc->keep_locks) {
8693 btrfs_tree_unlock_rw(eb, path->locks[level]);
8694 path->locks[level] = 0;
8699 /* wc->stage == UPDATE_BACKREF */
8700 if (!(wc->flags[level] & flag)) {
8701 BUG_ON(!path->locks[level]);
8702 ret = btrfs_inc_ref(trans, root, eb, 1);
8703 BUG_ON(ret); /* -ENOMEM */
8704 ret = btrfs_dec_ref(trans, root, eb, 0);
8705 BUG_ON(ret); /* -ENOMEM */
8706 ret = btrfs_set_disk_extent_flags(trans, fs_info, eb->start,
8708 btrfs_header_level(eb), 0);
8709 BUG_ON(ret); /* -ENOMEM */
8710 wc->flags[level] |= flag;
8714 * the block is shared by multiple trees, so it's not good to
8715 * keep the tree lock
8717 if (path->locks[level] && level > 0) {
8718 btrfs_tree_unlock_rw(eb, path->locks[level]);
8719 path->locks[level] = 0;
8725 * helper to process tree block pointer.
8727 * when wc->stage == DROP_REFERENCE, this function checks
8728 * reference count of the block pointed to. if the block
8729 * is shared and we need update back refs for the subtree
8730 * rooted at the block, this function changes wc->stage to
8731 * UPDATE_BACKREF. if the block is shared and there is no
8732 * need to update back, this function drops the reference
8735 * NOTE: return value 1 means we should stop walking down.
8737 static noinline int do_walk_down(struct btrfs_trans_handle *trans,
8738 struct btrfs_root *root,
8739 struct btrfs_path *path,
8740 struct walk_control *wc, int *lookup_info)
8742 struct btrfs_fs_info *fs_info = root->fs_info;
8747 struct btrfs_key key;
8748 struct btrfs_key first_key;
8749 struct extent_buffer *next;
8750 int level = wc->level;
8753 bool need_account = false;
8755 generation = btrfs_node_ptr_generation(path->nodes[level],
8756 path->slots[level]);
8758 * if the lower level block was created before the snapshot
8759 * was created, we know there is no need to update back refs
8762 if (wc->stage == UPDATE_BACKREF &&
8763 generation <= root->root_key.offset) {
8768 bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]);
8769 btrfs_node_key_to_cpu(path->nodes[level], &first_key,
8770 path->slots[level]);
8771 blocksize = fs_info->nodesize;
8773 next = find_extent_buffer(fs_info, bytenr);
8775 next = btrfs_find_create_tree_block(fs_info, bytenr);
8777 return PTR_ERR(next);
8779 btrfs_set_buffer_lockdep_class(root->root_key.objectid, next,
8783 btrfs_tree_lock(next);
8784 btrfs_set_lock_blocking(next);
8786 ret = btrfs_lookup_extent_info(trans, fs_info, bytenr, level - 1, 1,
8787 &wc->refs[level - 1],
8788 &wc->flags[level - 1]);
8792 if (unlikely(wc->refs[level - 1] == 0)) {
8793 btrfs_err(fs_info, "Missing references.");
8799 if (wc->stage == DROP_REFERENCE) {
8800 if (wc->refs[level - 1] > 1) {
8801 need_account = true;
8803 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
8806 if (!wc->update_ref ||
8807 generation <= root->root_key.offset)
8810 btrfs_node_key_to_cpu(path->nodes[level], &key,
8811 path->slots[level]);
8812 ret = btrfs_comp_cpu_keys(&key, &wc->update_progress);
8816 wc->stage = UPDATE_BACKREF;
8817 wc->shared_level = level - 1;
8821 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
8825 if (!btrfs_buffer_uptodate(next, generation, 0)) {
8826 btrfs_tree_unlock(next);
8827 free_extent_buffer(next);
8833 if (reada && level == 1)
8834 reada_walk_down(trans, root, wc, path);
8835 next = read_tree_block(fs_info, bytenr, generation, level - 1,
8838 return PTR_ERR(next);
8839 } else if (!extent_buffer_uptodate(next)) {
8840 free_extent_buffer(next);
8843 btrfs_tree_lock(next);
8844 btrfs_set_lock_blocking(next);
8848 ASSERT(level == btrfs_header_level(next));
8849 if (level != btrfs_header_level(next)) {
8850 btrfs_err(root->fs_info, "mismatched level");
8854 path->nodes[level] = next;
8855 path->slots[level] = 0;
8856 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
8862 wc->refs[level - 1] = 0;
8863 wc->flags[level - 1] = 0;
8864 if (wc->stage == DROP_REFERENCE) {
8865 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
8866 parent = path->nodes[level]->start;
8868 ASSERT(root->root_key.objectid ==
8869 btrfs_header_owner(path->nodes[level]));
8870 if (root->root_key.objectid !=
8871 btrfs_header_owner(path->nodes[level])) {
8872 btrfs_err(root->fs_info,
8873 "mismatched block owner");
8881 ret = btrfs_qgroup_trace_subtree(trans, root, next,
8882 generation, level - 1);
8884 btrfs_err_rl(fs_info,
8885 "Error %d accounting shared subtree. Quota is out of sync, rescan required.",
8889 ret = btrfs_free_extent(trans, root, bytenr, blocksize,
8890 parent, root->root_key.objectid,
8900 btrfs_tree_unlock(next);
8901 free_extent_buffer(next);
8907 * helper to process tree block while walking up the tree.
8909 * when wc->stage == DROP_REFERENCE, this function drops
8910 * reference count on the block.
8912 * when wc->stage == UPDATE_BACKREF, this function changes
8913 * wc->stage back to DROP_REFERENCE if we changed wc->stage
8914 * to UPDATE_BACKREF previously while processing the block.
8916 * NOTE: return value 1 means we should stop walking up.
8918 static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
8919 struct btrfs_root *root,
8920 struct btrfs_path *path,
8921 struct walk_control *wc)
8923 struct btrfs_fs_info *fs_info = root->fs_info;
8925 int level = wc->level;
8926 struct extent_buffer *eb = path->nodes[level];
8929 if (wc->stage == UPDATE_BACKREF) {
8930 BUG_ON(wc->shared_level < level);
8931 if (level < wc->shared_level)
8934 ret = find_next_key(path, level + 1, &wc->update_progress);
8938 wc->stage = DROP_REFERENCE;
8939 wc->shared_level = -1;
8940 path->slots[level] = 0;
8943 * check reference count again if the block isn't locked.
8944 * we should start walking down the tree again if reference
8947 if (!path->locks[level]) {
8949 btrfs_tree_lock(eb);
8950 btrfs_set_lock_blocking(eb);
8951 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
8953 ret = btrfs_lookup_extent_info(trans, fs_info,
8954 eb->start, level, 1,
8958 btrfs_tree_unlock_rw(eb, path->locks[level]);
8959 path->locks[level] = 0;
8962 BUG_ON(wc->refs[level] == 0);
8963 if (wc->refs[level] == 1) {
8964 btrfs_tree_unlock_rw(eb, path->locks[level]);
8965 path->locks[level] = 0;
8971 /* wc->stage == DROP_REFERENCE */
8972 BUG_ON(wc->refs[level] > 1 && !path->locks[level]);
8974 if (wc->refs[level] == 1) {
8976 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
8977 ret = btrfs_dec_ref(trans, root, eb, 1);
8979 ret = btrfs_dec_ref(trans, root, eb, 0);
8980 BUG_ON(ret); /* -ENOMEM */
8981 ret = btrfs_qgroup_trace_leaf_items(trans, fs_info, eb);
8983 btrfs_err_rl(fs_info,
8984 "error %d accounting leaf items. Quota is out of sync, rescan required.",
8988 /* make block locked assertion in clean_tree_block happy */
8989 if (!path->locks[level] &&
8990 btrfs_header_generation(eb) == trans->transid) {
8991 btrfs_tree_lock(eb);
8992 btrfs_set_lock_blocking(eb);
8993 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
8995 clean_tree_block(fs_info, eb);
8998 if (eb == root->node) {
8999 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
9002 BUG_ON(root->root_key.objectid !=
9003 btrfs_header_owner(eb));
9005 if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
9006 parent = path->nodes[level + 1]->start;
9008 BUG_ON(root->root_key.objectid !=
9009 btrfs_header_owner(path->nodes[level + 1]));
9012 btrfs_free_tree_block(trans, root, eb, parent, wc->refs[level] == 1);
9014 wc->refs[level] = 0;
9015 wc->flags[level] = 0;
9019 static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
9020 struct btrfs_root *root,
9021 struct btrfs_path *path,
9022 struct walk_control *wc)
9024 int level = wc->level;
9025 int lookup_info = 1;
9028 while (level >= 0) {
9029 ret = walk_down_proc(trans, root, path, wc, lookup_info);
9036 if (path->slots[level] >=
9037 btrfs_header_nritems(path->nodes[level]))
9040 ret = do_walk_down(trans, root, path, wc, &lookup_info);
9042 path->slots[level]++;
9051 static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
9052 struct btrfs_root *root,
9053 struct btrfs_path *path,
9054 struct walk_control *wc, int max_level)
9056 int level = wc->level;
9059 path->slots[level] = btrfs_header_nritems(path->nodes[level]);
9060 while (level < max_level && path->nodes[level]) {
9062 if (path->slots[level] + 1 <
9063 btrfs_header_nritems(path->nodes[level])) {
9064 path->slots[level]++;
9067 ret = walk_up_proc(trans, root, path, wc);
9071 if (path->locks[level]) {
9072 btrfs_tree_unlock_rw(path->nodes[level],
9073 path->locks[level]);
9074 path->locks[level] = 0;
9076 free_extent_buffer(path->nodes[level]);
9077 path->nodes[level] = NULL;
9085 * drop a subvolume tree.
9087 * this function traverses the tree freeing any blocks that only
9088 * referenced by the tree.
9090 * when a shared tree block is found. this function decreases its
9091 * reference count by one. if update_ref is true, this function
9092 * also make sure backrefs for the shared block and all lower level
9093 * blocks are properly updated.
9095 * If called with for_reloc == 0, may exit early with -EAGAIN
9097 int btrfs_drop_snapshot(struct btrfs_root *root,
9098 struct btrfs_block_rsv *block_rsv, int update_ref,
9101 struct btrfs_fs_info *fs_info = root->fs_info;
9102 struct btrfs_path *path;
9103 struct btrfs_trans_handle *trans;
9104 struct btrfs_root *tree_root = fs_info->tree_root;
9105 struct btrfs_root_item *root_item = &root->root_item;
9106 struct walk_control *wc;
9107 struct btrfs_key key;
9111 bool root_dropped = false;
9113 btrfs_debug(fs_info, "Drop subvolume %llu", root->objectid);
9115 path = btrfs_alloc_path();
9121 wc = kzalloc(sizeof(*wc), GFP_NOFS);
9123 btrfs_free_path(path);
9128 trans = btrfs_start_transaction(tree_root, 0);
9129 if (IS_ERR(trans)) {
9130 err = PTR_ERR(trans);
9135 trans->block_rsv = block_rsv;
9137 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
9138 level = btrfs_header_level(root->node);
9139 path->nodes[level] = btrfs_lock_root_node(root);
9140 btrfs_set_lock_blocking(path->nodes[level]);
9141 path->slots[level] = 0;
9142 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
9143 memset(&wc->update_progress, 0,
9144 sizeof(wc->update_progress));
9146 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
9147 memcpy(&wc->update_progress, &key,
9148 sizeof(wc->update_progress));
9150 level = root_item->drop_level;
9152 path->lowest_level = level;
9153 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
9154 path->lowest_level = 0;
9162 * unlock our path, this is safe because only this
9163 * function is allowed to delete this snapshot
9165 btrfs_unlock_up_safe(path, 0);
9167 level = btrfs_header_level(root->node);
9169 btrfs_tree_lock(path->nodes[level]);
9170 btrfs_set_lock_blocking(path->nodes[level]);
9171 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
9173 ret = btrfs_lookup_extent_info(trans, fs_info,
9174 path->nodes[level]->start,
9175 level, 1, &wc->refs[level],
9181 BUG_ON(wc->refs[level] == 0);
9183 if (level == root_item->drop_level)
9186 btrfs_tree_unlock(path->nodes[level]);
9187 path->locks[level] = 0;
9188 WARN_ON(wc->refs[level] != 1);
9194 wc->shared_level = -1;
9195 wc->stage = DROP_REFERENCE;
9196 wc->update_ref = update_ref;
9198 wc->for_reloc = for_reloc;
9199 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(fs_info);
9203 ret = walk_down_tree(trans, root, path, wc);
9209 ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL);
9216 BUG_ON(wc->stage != DROP_REFERENCE);
9220 if (wc->stage == DROP_REFERENCE) {
9222 btrfs_node_key(path->nodes[level],
9223 &root_item->drop_progress,
9224 path->slots[level]);
9225 root_item->drop_level = level;
9228 BUG_ON(wc->level == 0);
9229 if (btrfs_should_end_transaction(trans) ||
9230 (!for_reloc && btrfs_need_cleaner_sleep(fs_info))) {
9231 ret = btrfs_update_root(trans, tree_root,
9235 btrfs_abort_transaction(trans, ret);
9240 btrfs_end_transaction_throttle(trans);
9241 if (!for_reloc && btrfs_need_cleaner_sleep(fs_info)) {
9242 btrfs_debug(fs_info,
9243 "drop snapshot early exit");
9248 trans = btrfs_start_transaction(tree_root, 0);
9249 if (IS_ERR(trans)) {
9250 err = PTR_ERR(trans);
9254 trans->block_rsv = block_rsv;
9257 btrfs_release_path(path);
9261 ret = btrfs_del_root(trans, fs_info, &root->root_key);
9263 btrfs_abort_transaction(trans, ret);
9268 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
9269 ret = btrfs_find_root(tree_root, &root->root_key, path,
9272 btrfs_abort_transaction(trans, ret);
9275 } else if (ret > 0) {
9276 /* if we fail to delete the orphan item this time
9277 * around, it'll get picked up the next time.
9279 * The most common failure here is just -ENOENT.
9281 btrfs_del_orphan_item(trans, tree_root,
9282 root->root_key.objectid);
9286 if (test_bit(BTRFS_ROOT_IN_RADIX, &root->state)) {
9287 btrfs_add_dropped_root(trans, root);
9289 free_extent_buffer(root->node);
9290 free_extent_buffer(root->commit_root);
9291 btrfs_put_fs_root(root);
9293 root_dropped = true;
9295 btrfs_end_transaction_throttle(trans);
9298 btrfs_free_path(path);
9301 * So if we need to stop dropping the snapshot for whatever reason we
9302 * need to make sure to add it back to the dead root list so that we
9303 * keep trying to do the work later. This also cleans up roots if we
9304 * don't have it in the radix (like when we recover after a power fail
9305 * or unmount) so we don't leak memory.
9307 if (!for_reloc && !root_dropped)
9308 btrfs_add_dead_root(root);
9309 if (err && err != -EAGAIN)
9310 btrfs_handle_fs_error(fs_info, err, NULL);
9315 * drop subtree rooted at tree block 'node'.
9317 * NOTE: this function will unlock and release tree block 'node'
9318 * only used by relocation code
9320 int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
9321 struct btrfs_root *root,
9322 struct extent_buffer *node,
9323 struct extent_buffer *parent)
9325 struct btrfs_fs_info *fs_info = root->fs_info;
9326 struct btrfs_path *path;
9327 struct walk_control *wc;
9333 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
9335 path = btrfs_alloc_path();
9339 wc = kzalloc(sizeof(*wc), GFP_NOFS);
9341 btrfs_free_path(path);
9345 btrfs_assert_tree_locked(parent);
9346 parent_level = btrfs_header_level(parent);
9347 extent_buffer_get(parent);
9348 path->nodes[parent_level] = parent;
9349 path->slots[parent_level] = btrfs_header_nritems(parent);
9351 btrfs_assert_tree_locked(node);
9352 level = btrfs_header_level(node);
9353 path->nodes[level] = node;
9354 path->slots[level] = 0;
9355 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
9357 wc->refs[parent_level] = 1;
9358 wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF;
9360 wc->shared_level = -1;
9361 wc->stage = DROP_REFERENCE;
9365 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(fs_info);
9368 wret = walk_down_tree(trans, root, path, wc);
9374 wret = walk_up_tree(trans, root, path, wc, parent_level);
9382 btrfs_free_path(path);
9386 static u64 update_block_group_flags(struct btrfs_fs_info *fs_info, u64 flags)
9392 * if restripe for this chunk_type is on pick target profile and
9393 * return, otherwise do the usual balance
9395 stripped = get_restripe_target(fs_info, flags);
9397 return extended_to_chunk(stripped);
9399 num_devices = fs_info->fs_devices->rw_devices;
9401 stripped = BTRFS_BLOCK_GROUP_RAID0 |
9402 BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6 |
9403 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
9405 if (num_devices == 1) {
9406 stripped |= BTRFS_BLOCK_GROUP_DUP;
9407 stripped = flags & ~stripped;
9409 /* turn raid0 into single device chunks */
9410 if (flags & BTRFS_BLOCK_GROUP_RAID0)
9413 /* turn mirroring into duplication */
9414 if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
9415 BTRFS_BLOCK_GROUP_RAID10))
9416 return stripped | BTRFS_BLOCK_GROUP_DUP;
9418 /* they already had raid on here, just return */
9419 if (flags & stripped)
9422 stripped |= BTRFS_BLOCK_GROUP_DUP;
9423 stripped = flags & ~stripped;
9425 /* switch duplicated blocks with raid1 */
9426 if (flags & BTRFS_BLOCK_GROUP_DUP)
9427 return stripped | BTRFS_BLOCK_GROUP_RAID1;
9429 /* this is drive concat, leave it alone */
9435 static int inc_block_group_ro(struct btrfs_block_group_cache *cache, int force)
9437 struct btrfs_space_info *sinfo = cache->space_info;
9439 u64 min_allocable_bytes;
9443 * We need some metadata space and system metadata space for
9444 * allocating chunks in some corner cases until we force to set
9445 * it to be readonly.
9448 (BTRFS_BLOCK_GROUP_SYSTEM | BTRFS_BLOCK_GROUP_METADATA)) &&
9450 min_allocable_bytes = SZ_1M;
9452 min_allocable_bytes = 0;
9454 spin_lock(&sinfo->lock);
9455 spin_lock(&cache->lock);
9463 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
9464 cache->bytes_super - btrfs_block_group_used(&cache->item);
9466 if (btrfs_space_info_used(sinfo, true) + num_bytes +
9467 min_allocable_bytes <= sinfo->total_bytes) {
9468 sinfo->bytes_readonly += num_bytes;
9470 list_add_tail(&cache->ro_list, &sinfo->ro_bgs);
9474 spin_unlock(&cache->lock);
9475 spin_unlock(&sinfo->lock);
9479 int btrfs_inc_block_group_ro(struct btrfs_fs_info *fs_info,
9480 struct btrfs_block_group_cache *cache)
9483 struct btrfs_trans_handle *trans;
9488 trans = btrfs_join_transaction(fs_info->extent_root);
9490 return PTR_ERR(trans);
9493 * we're not allowed to set block groups readonly after the dirty
9494 * block groups cache has started writing. If it already started,
9495 * back off and let this transaction commit
9497 mutex_lock(&fs_info->ro_block_group_mutex);
9498 if (test_bit(BTRFS_TRANS_DIRTY_BG_RUN, &trans->transaction->flags)) {
9499 u64 transid = trans->transid;
9501 mutex_unlock(&fs_info->ro_block_group_mutex);
9502 btrfs_end_transaction(trans);
9504 ret = btrfs_wait_for_commit(fs_info, transid);
9511 * if we are changing raid levels, try to allocate a corresponding
9512 * block group with the new raid level.
9514 alloc_flags = update_block_group_flags(fs_info, cache->flags);
9515 if (alloc_flags != cache->flags) {
9516 ret = do_chunk_alloc(trans, fs_info, alloc_flags,
9519 * ENOSPC is allowed here, we may have enough space
9520 * already allocated at the new raid level to
9529 ret = inc_block_group_ro(cache, 0);
9532 alloc_flags = get_alloc_profile(fs_info, cache->space_info->flags);
9533 ret = do_chunk_alloc(trans, fs_info, alloc_flags,
9537 ret = inc_block_group_ro(cache, 0);
9539 if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM) {
9540 alloc_flags = update_block_group_flags(fs_info, cache->flags);
9541 mutex_lock(&fs_info->chunk_mutex);
9542 check_system_chunk(trans, fs_info, alloc_flags);
9543 mutex_unlock(&fs_info->chunk_mutex);
9545 mutex_unlock(&fs_info->ro_block_group_mutex);
9547 btrfs_end_transaction(trans);
9551 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans,
9552 struct btrfs_fs_info *fs_info, u64 type)
9554 u64 alloc_flags = get_alloc_profile(fs_info, type);
9556 return do_chunk_alloc(trans, fs_info, alloc_flags, CHUNK_ALLOC_FORCE);
9560 * helper to account the unused space of all the readonly block group in the
9561 * space_info. takes mirrors into account.
9563 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo)
9565 struct btrfs_block_group_cache *block_group;
9569 /* It's df, we don't care if it's racy */
9570 if (list_empty(&sinfo->ro_bgs))
9573 spin_lock(&sinfo->lock);
9574 list_for_each_entry(block_group, &sinfo->ro_bgs, ro_list) {
9575 spin_lock(&block_group->lock);
9577 if (!block_group->ro) {
9578 spin_unlock(&block_group->lock);
9582 if (block_group->flags & (BTRFS_BLOCK_GROUP_RAID1 |
9583 BTRFS_BLOCK_GROUP_RAID10 |
9584 BTRFS_BLOCK_GROUP_DUP))
9589 free_bytes += (block_group->key.offset -
9590 btrfs_block_group_used(&block_group->item)) *
9593 spin_unlock(&block_group->lock);
9595 spin_unlock(&sinfo->lock);
9600 void btrfs_dec_block_group_ro(struct btrfs_block_group_cache *cache)
9602 struct btrfs_space_info *sinfo = cache->space_info;
9607 spin_lock(&sinfo->lock);
9608 spin_lock(&cache->lock);
9610 num_bytes = cache->key.offset - cache->reserved -
9611 cache->pinned - cache->bytes_super -
9612 btrfs_block_group_used(&cache->item);
9613 sinfo->bytes_readonly -= num_bytes;
9614 list_del_init(&cache->ro_list);
9616 spin_unlock(&cache->lock);
9617 spin_unlock(&sinfo->lock);
9621 * checks to see if its even possible to relocate this block group.
9623 * @return - -1 if it's not a good idea to relocate this block group, 0 if its
9624 * ok to go ahead and try.
9626 int btrfs_can_relocate(struct btrfs_fs_info *fs_info, u64 bytenr)
9628 struct btrfs_root *root = fs_info->extent_root;
9629 struct btrfs_block_group_cache *block_group;
9630 struct btrfs_space_info *space_info;
9631 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
9632 struct btrfs_device *device;
9633 struct btrfs_trans_handle *trans;
9643 debug = btrfs_test_opt(fs_info, ENOSPC_DEBUG);
9645 block_group = btrfs_lookup_block_group(fs_info, bytenr);
9647 /* odd, couldn't find the block group, leave it alone */
9651 "can't find block group for bytenr %llu",
9656 min_free = btrfs_block_group_used(&block_group->item);
9658 /* no bytes used, we're good */
9662 space_info = block_group->space_info;
9663 spin_lock(&space_info->lock);
9665 full = space_info->full;
9668 * if this is the last block group we have in this space, we can't
9669 * relocate it unless we're able to allocate a new chunk below.
9671 * Otherwise, we need to make sure we have room in the space to handle
9672 * all of the extents from this block group. If we can, we're good
9674 if ((space_info->total_bytes != block_group->key.offset) &&
9675 (btrfs_space_info_used(space_info, false) + min_free <
9676 space_info->total_bytes)) {
9677 spin_unlock(&space_info->lock);
9680 spin_unlock(&space_info->lock);
9683 * ok we don't have enough space, but maybe we have free space on our
9684 * devices to allocate new chunks for relocation, so loop through our
9685 * alloc devices and guess if we have enough space. if this block
9686 * group is going to be restriped, run checks against the target
9687 * profile instead of the current one.
9699 target = get_restripe_target(fs_info, block_group->flags);
9701 index = btrfs_bg_flags_to_raid_index(extended_to_chunk(target));
9704 * this is just a balance, so if we were marked as full
9705 * we know there is no space for a new chunk
9710 "no space to alloc new chunk for block group %llu",
9711 block_group->key.objectid);
9715 index = btrfs_bg_flags_to_raid_index(block_group->flags);
9718 if (index == BTRFS_RAID_RAID10) {
9722 } else if (index == BTRFS_RAID_RAID1) {
9724 } else if (index == BTRFS_RAID_DUP) {
9727 } else if (index == BTRFS_RAID_RAID0) {
9728 dev_min = fs_devices->rw_devices;
9729 min_free = div64_u64(min_free, dev_min);
9732 /* We need to do this so that we can look at pending chunks */
9733 trans = btrfs_join_transaction(root);
9734 if (IS_ERR(trans)) {
9735 ret = PTR_ERR(trans);
9739 mutex_lock(&fs_info->chunk_mutex);
9740 list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
9744 * check to make sure we can actually find a chunk with enough
9745 * space to fit our block group in.
9747 if (device->total_bytes > device->bytes_used + min_free &&
9748 !test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
9749 ret = find_free_dev_extent(trans, device, min_free,
9754 if (dev_nr >= dev_min)
9760 if (debug && ret == -1)
9762 "no space to allocate a new chunk for block group %llu",
9763 block_group->key.objectid);
9764 mutex_unlock(&fs_info->chunk_mutex);
9765 btrfs_end_transaction(trans);
9767 btrfs_put_block_group(block_group);
9771 static int find_first_block_group(struct btrfs_fs_info *fs_info,
9772 struct btrfs_path *path,
9773 struct btrfs_key *key)
9775 struct btrfs_root *root = fs_info->extent_root;
9777 struct btrfs_key found_key;
9778 struct extent_buffer *leaf;
9781 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
9786 slot = path->slots[0];
9787 leaf = path->nodes[0];
9788 if (slot >= btrfs_header_nritems(leaf)) {
9789 ret = btrfs_next_leaf(root, path);
9796 btrfs_item_key_to_cpu(leaf, &found_key, slot);
9798 if (found_key.objectid >= key->objectid &&
9799 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
9800 struct extent_map_tree *em_tree;
9801 struct extent_map *em;
9803 em_tree = &root->fs_info->mapping_tree.map_tree;
9804 read_lock(&em_tree->lock);
9805 em = lookup_extent_mapping(em_tree, found_key.objectid,
9807 read_unlock(&em_tree->lock);
9810 "logical %llu len %llu found bg but no related chunk",
9811 found_key.objectid, found_key.offset);
9816 free_extent_map(em);
9825 void btrfs_put_block_group_cache(struct btrfs_fs_info *info)
9827 struct btrfs_block_group_cache *block_group;
9831 struct inode *inode;
9833 block_group = btrfs_lookup_first_block_group(info, last);
9834 while (block_group) {
9835 spin_lock(&block_group->lock);
9836 if (block_group->iref)
9838 spin_unlock(&block_group->lock);
9839 block_group = next_block_group(info, block_group);
9848 inode = block_group->inode;
9849 block_group->iref = 0;
9850 block_group->inode = NULL;
9851 spin_unlock(&block_group->lock);
9852 ASSERT(block_group->io_ctl.inode == NULL);
9854 last = block_group->key.objectid + block_group->key.offset;
9855 btrfs_put_block_group(block_group);
9860 * Must be called only after stopping all workers, since we could have block
9861 * group caching kthreads running, and therefore they could race with us if we
9862 * freed the block groups before stopping them.
9864 int btrfs_free_block_groups(struct btrfs_fs_info *info)
9866 struct btrfs_block_group_cache *block_group;
9867 struct btrfs_space_info *space_info;
9868 struct btrfs_caching_control *caching_ctl;
9871 down_write(&info->commit_root_sem);
9872 while (!list_empty(&info->caching_block_groups)) {
9873 caching_ctl = list_entry(info->caching_block_groups.next,
9874 struct btrfs_caching_control, list);
9875 list_del(&caching_ctl->list);
9876 put_caching_control(caching_ctl);
9878 up_write(&info->commit_root_sem);
9880 spin_lock(&info->unused_bgs_lock);
9881 while (!list_empty(&info->unused_bgs)) {
9882 block_group = list_first_entry(&info->unused_bgs,
9883 struct btrfs_block_group_cache,
9885 list_del_init(&block_group->bg_list);
9886 btrfs_put_block_group(block_group);
9888 spin_unlock(&info->unused_bgs_lock);
9890 spin_lock(&info->block_group_cache_lock);
9891 while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
9892 block_group = rb_entry(n, struct btrfs_block_group_cache,
9894 rb_erase(&block_group->cache_node,
9895 &info->block_group_cache_tree);
9896 RB_CLEAR_NODE(&block_group->cache_node);
9897 spin_unlock(&info->block_group_cache_lock);
9899 down_write(&block_group->space_info->groups_sem);
9900 list_del(&block_group->list);
9901 up_write(&block_group->space_info->groups_sem);
9904 * We haven't cached this block group, which means we could
9905 * possibly have excluded extents on this block group.
9907 if (block_group->cached == BTRFS_CACHE_NO ||
9908 block_group->cached == BTRFS_CACHE_ERROR)
9909 free_excluded_extents(info, block_group);
9911 btrfs_remove_free_space_cache(block_group);
9912 ASSERT(block_group->cached != BTRFS_CACHE_STARTED);
9913 ASSERT(list_empty(&block_group->dirty_list));
9914 ASSERT(list_empty(&block_group->io_list));
9915 ASSERT(list_empty(&block_group->bg_list));
9916 ASSERT(atomic_read(&block_group->count) == 1);
9917 btrfs_put_block_group(block_group);
9919 spin_lock(&info->block_group_cache_lock);
9921 spin_unlock(&info->block_group_cache_lock);
9923 /* now that all the block groups are freed, go through and
9924 * free all the space_info structs. This is only called during
9925 * the final stages of unmount, and so we know nobody is
9926 * using them. We call synchronize_rcu() once before we start,
9927 * just to be on the safe side.
9931 release_global_block_rsv(info);
9933 while (!list_empty(&info->space_info)) {
9936 space_info = list_entry(info->space_info.next,
9937 struct btrfs_space_info,
9941 * Do not hide this behind enospc_debug, this is actually
9942 * important and indicates a real bug if this happens.
9944 if (WARN_ON(space_info->bytes_pinned > 0 ||
9945 space_info->bytes_reserved > 0 ||
9946 space_info->bytes_may_use > 0))
9947 dump_space_info(info, space_info, 0, 0);
9948 list_del(&space_info->list);
9949 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
9950 struct kobject *kobj;
9951 kobj = space_info->block_group_kobjs[i];
9952 space_info->block_group_kobjs[i] = NULL;
9958 kobject_del(&space_info->kobj);
9959 kobject_put(&space_info->kobj);
9964 /* link_block_group will queue up kobjects to add when we're reclaim-safe */
9965 void btrfs_add_raid_kobjects(struct btrfs_fs_info *fs_info)
9967 struct btrfs_space_info *space_info;
9968 struct raid_kobject *rkobj;
9973 spin_lock(&fs_info->pending_raid_kobjs_lock);
9974 list_splice_init(&fs_info->pending_raid_kobjs, &list);
9975 spin_unlock(&fs_info->pending_raid_kobjs_lock);
9977 list_for_each_entry(rkobj, &list, list) {
9978 space_info = __find_space_info(fs_info, rkobj->flags);
9979 index = btrfs_bg_flags_to_raid_index(rkobj->flags);
9981 ret = kobject_add(&rkobj->kobj, &space_info->kobj,
9982 "%s", get_raid_name(index));
9984 kobject_put(&rkobj->kobj);
9990 "failed to add kobject for block cache, ignoring");
9993 static void link_block_group(struct btrfs_block_group_cache *cache)
9995 struct btrfs_space_info *space_info = cache->space_info;
9996 struct btrfs_fs_info *fs_info = cache->fs_info;
9997 int index = btrfs_bg_flags_to_raid_index(cache->flags);
10000 down_write(&space_info->groups_sem);
10001 if (list_empty(&space_info->block_groups[index]))
10003 list_add_tail(&cache->list, &space_info->block_groups[index]);
10004 up_write(&space_info->groups_sem);
10007 struct raid_kobject *rkobj = kzalloc(sizeof(*rkobj), GFP_NOFS);
10009 btrfs_warn(cache->fs_info,
10010 "couldn't alloc memory for raid level kobject");
10013 rkobj->flags = cache->flags;
10014 kobject_init(&rkobj->kobj, &btrfs_raid_ktype);
10016 spin_lock(&fs_info->pending_raid_kobjs_lock);
10017 list_add_tail(&rkobj->list, &fs_info->pending_raid_kobjs);
10018 spin_unlock(&fs_info->pending_raid_kobjs_lock);
10019 space_info->block_group_kobjs[index] = &rkobj->kobj;
10023 static struct btrfs_block_group_cache *
10024 btrfs_create_block_group_cache(struct btrfs_fs_info *fs_info,
10025 u64 start, u64 size)
10027 struct btrfs_block_group_cache *cache;
10029 cache = kzalloc(sizeof(*cache), GFP_NOFS);
10033 cache->free_space_ctl = kzalloc(sizeof(*cache->free_space_ctl),
10035 if (!cache->free_space_ctl) {
10040 cache->key.objectid = start;
10041 cache->key.offset = size;
10042 cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
10044 cache->fs_info = fs_info;
10045 cache->full_stripe_len = btrfs_full_stripe_len(fs_info, start);
10046 set_free_space_tree_thresholds(cache);
10048 atomic_set(&cache->count, 1);
10049 spin_lock_init(&cache->lock);
10050 init_rwsem(&cache->data_rwsem);
10051 INIT_LIST_HEAD(&cache->list);
10052 INIT_LIST_HEAD(&cache->cluster_list);
10053 INIT_LIST_HEAD(&cache->bg_list);
10054 INIT_LIST_HEAD(&cache->ro_list);
10055 INIT_LIST_HEAD(&cache->dirty_list);
10056 INIT_LIST_HEAD(&cache->io_list);
10057 btrfs_init_free_space_ctl(cache);
10058 atomic_set(&cache->trimming, 0);
10059 mutex_init(&cache->free_space_lock);
10060 btrfs_init_full_stripe_locks_tree(&cache->full_stripe_locks_root);
10065 int btrfs_read_block_groups(struct btrfs_fs_info *info)
10067 struct btrfs_path *path;
10069 struct btrfs_block_group_cache *cache;
10070 struct btrfs_space_info *space_info;
10071 struct btrfs_key key;
10072 struct btrfs_key found_key;
10073 struct extent_buffer *leaf;
10074 int need_clear = 0;
10079 feature = btrfs_super_incompat_flags(info->super_copy);
10080 mixed = !!(feature & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS);
10084 key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
10085 path = btrfs_alloc_path();
10088 path->reada = READA_FORWARD;
10090 cache_gen = btrfs_super_cache_generation(info->super_copy);
10091 if (btrfs_test_opt(info, SPACE_CACHE) &&
10092 btrfs_super_generation(info->super_copy) != cache_gen)
10094 if (btrfs_test_opt(info, CLEAR_CACHE))
10098 ret = find_first_block_group(info, path, &key);
10104 leaf = path->nodes[0];
10105 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
10107 cache = btrfs_create_block_group_cache(info, found_key.objectid,
10116 * When we mount with old space cache, we need to
10117 * set BTRFS_DC_CLEAR and set dirty flag.
10119 * a) Setting 'BTRFS_DC_CLEAR' makes sure that we
10120 * truncate the old free space cache inode and
10122 * b) Setting 'dirty flag' makes sure that we flush
10123 * the new space cache info onto disk.
10125 if (btrfs_test_opt(info, SPACE_CACHE))
10126 cache->disk_cache_state = BTRFS_DC_CLEAR;
10129 read_extent_buffer(leaf, &cache->item,
10130 btrfs_item_ptr_offset(leaf, path->slots[0]),
10131 sizeof(cache->item));
10132 cache->flags = btrfs_block_group_flags(&cache->item);
10134 ((cache->flags & BTRFS_BLOCK_GROUP_METADATA) &&
10135 (cache->flags & BTRFS_BLOCK_GROUP_DATA))) {
10137 "bg %llu is a mixed block group but filesystem hasn't enabled mixed block groups",
10138 cache->key.objectid);
10143 key.objectid = found_key.objectid + found_key.offset;
10144 btrfs_release_path(path);
10147 * We need to exclude the super stripes now so that the space
10148 * info has super bytes accounted for, otherwise we'll think
10149 * we have more space than we actually do.
10151 ret = exclude_super_stripes(info, cache);
10154 * We may have excluded something, so call this just in
10157 free_excluded_extents(info, cache);
10158 btrfs_put_block_group(cache);
10163 * check for two cases, either we are full, and therefore
10164 * don't need to bother with the caching work since we won't
10165 * find any space, or we are empty, and we can just add all
10166 * the space in and be done with it. This saves us _alot_ of
10167 * time, particularly in the full case.
10169 if (found_key.offset == btrfs_block_group_used(&cache->item)) {
10170 cache->last_byte_to_unpin = (u64)-1;
10171 cache->cached = BTRFS_CACHE_FINISHED;
10172 free_excluded_extents(info, cache);
10173 } else if (btrfs_block_group_used(&cache->item) == 0) {
10174 cache->last_byte_to_unpin = (u64)-1;
10175 cache->cached = BTRFS_CACHE_FINISHED;
10176 add_new_free_space(cache, info,
10177 found_key.objectid,
10178 found_key.objectid +
10180 free_excluded_extents(info, cache);
10183 ret = btrfs_add_block_group_cache(info, cache);
10185 btrfs_remove_free_space_cache(cache);
10186 btrfs_put_block_group(cache);
10190 trace_btrfs_add_block_group(info, cache, 0);
10191 update_space_info(info, cache->flags, found_key.offset,
10192 btrfs_block_group_used(&cache->item),
10193 cache->bytes_super, &space_info);
10195 cache->space_info = space_info;
10197 link_block_group(cache);
10199 set_avail_alloc_bits(info, cache->flags);
10200 if (btrfs_chunk_readonly(info, cache->key.objectid)) {
10201 inc_block_group_ro(cache, 1);
10202 } else if (btrfs_block_group_used(&cache->item) == 0) {
10203 spin_lock(&info->unused_bgs_lock);
10204 /* Should always be true but just in case. */
10205 if (list_empty(&cache->bg_list)) {
10206 btrfs_get_block_group(cache);
10207 list_add_tail(&cache->bg_list,
10208 &info->unused_bgs);
10210 spin_unlock(&info->unused_bgs_lock);
10214 list_for_each_entry_rcu(space_info, &info->space_info, list) {
10215 if (!(get_alloc_profile(info, space_info->flags) &
10216 (BTRFS_BLOCK_GROUP_RAID10 |
10217 BTRFS_BLOCK_GROUP_RAID1 |
10218 BTRFS_BLOCK_GROUP_RAID5 |
10219 BTRFS_BLOCK_GROUP_RAID6 |
10220 BTRFS_BLOCK_GROUP_DUP)))
10223 * avoid allocating from un-mirrored block group if there are
10224 * mirrored block groups.
10226 list_for_each_entry(cache,
10227 &space_info->block_groups[BTRFS_RAID_RAID0],
10229 inc_block_group_ro(cache, 1);
10230 list_for_each_entry(cache,
10231 &space_info->block_groups[BTRFS_RAID_SINGLE],
10233 inc_block_group_ro(cache, 1);
10236 btrfs_add_raid_kobjects(info);
10237 init_global_block_rsv(info);
10240 btrfs_free_path(path);
10244 void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans)
10246 struct btrfs_fs_info *fs_info = trans->fs_info;
10247 struct btrfs_block_group_cache *block_group, *tmp;
10248 struct btrfs_root *extent_root = fs_info->extent_root;
10249 struct btrfs_block_group_item item;
10250 struct btrfs_key key;
10252 bool can_flush_pending_bgs = trans->can_flush_pending_bgs;
10254 trans->can_flush_pending_bgs = false;
10255 list_for_each_entry_safe(block_group, tmp, &trans->new_bgs, bg_list) {
10259 spin_lock(&block_group->lock);
10260 memcpy(&item, &block_group->item, sizeof(item));
10261 memcpy(&key, &block_group->key, sizeof(key));
10262 spin_unlock(&block_group->lock);
10264 ret = btrfs_insert_item(trans, extent_root, &key, &item,
10267 btrfs_abort_transaction(trans, ret);
10268 ret = btrfs_finish_chunk_alloc(trans, fs_info, key.objectid,
10271 btrfs_abort_transaction(trans, ret);
10272 add_block_group_free_space(trans, fs_info, block_group);
10273 /* already aborted the transaction if it failed. */
10275 list_del_init(&block_group->bg_list);
10277 trans->can_flush_pending_bgs = can_flush_pending_bgs;
10280 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
10281 struct btrfs_fs_info *fs_info, u64 bytes_used,
10282 u64 type, u64 chunk_offset, u64 size)
10284 struct btrfs_block_group_cache *cache;
10287 btrfs_set_log_full_commit(fs_info, trans);
10289 cache = btrfs_create_block_group_cache(fs_info, chunk_offset, size);
10293 btrfs_set_block_group_used(&cache->item, bytes_used);
10294 btrfs_set_block_group_chunk_objectid(&cache->item,
10295 BTRFS_FIRST_CHUNK_TREE_OBJECTID);
10296 btrfs_set_block_group_flags(&cache->item, type);
10298 cache->flags = type;
10299 cache->last_byte_to_unpin = (u64)-1;
10300 cache->cached = BTRFS_CACHE_FINISHED;
10301 cache->needs_free_space = 1;
10302 ret = exclude_super_stripes(fs_info, cache);
10305 * We may have excluded something, so call this just in
10308 free_excluded_extents(fs_info, cache);
10309 btrfs_put_block_group(cache);
10313 add_new_free_space(cache, fs_info, chunk_offset, chunk_offset + size);
10315 free_excluded_extents(fs_info, cache);
10317 #ifdef CONFIG_BTRFS_DEBUG
10318 if (btrfs_should_fragment_free_space(cache)) {
10319 u64 new_bytes_used = size - bytes_used;
10321 bytes_used += new_bytes_used >> 1;
10322 fragment_free_space(cache);
10326 * Ensure the corresponding space_info object is created and
10327 * assigned to our block group. We want our bg to be added to the rbtree
10328 * with its ->space_info set.
10330 cache->space_info = __find_space_info(fs_info, cache->flags);
10331 ASSERT(cache->space_info);
10333 ret = btrfs_add_block_group_cache(fs_info, cache);
10335 btrfs_remove_free_space_cache(cache);
10336 btrfs_put_block_group(cache);
10341 * Now that our block group has its ->space_info set and is inserted in
10342 * the rbtree, update the space info's counters.
10344 trace_btrfs_add_block_group(fs_info, cache, 1);
10345 update_space_info(fs_info, cache->flags, size, bytes_used,
10346 cache->bytes_super, &cache->space_info);
10347 update_global_block_rsv(fs_info);
10349 link_block_group(cache);
10351 list_add_tail(&cache->bg_list, &trans->new_bgs);
10353 set_avail_alloc_bits(fs_info, type);
10357 static void clear_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
10359 u64 extra_flags = chunk_to_extended(flags) &
10360 BTRFS_EXTENDED_PROFILE_MASK;
10362 write_seqlock(&fs_info->profiles_lock);
10363 if (flags & BTRFS_BLOCK_GROUP_DATA)
10364 fs_info->avail_data_alloc_bits &= ~extra_flags;
10365 if (flags & BTRFS_BLOCK_GROUP_METADATA)
10366 fs_info->avail_metadata_alloc_bits &= ~extra_flags;
10367 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
10368 fs_info->avail_system_alloc_bits &= ~extra_flags;
10369 write_sequnlock(&fs_info->profiles_lock);
10372 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
10373 struct btrfs_fs_info *fs_info, u64 group_start,
10374 struct extent_map *em)
10376 struct btrfs_root *root = fs_info->extent_root;
10377 struct btrfs_path *path;
10378 struct btrfs_block_group_cache *block_group;
10379 struct btrfs_free_cluster *cluster;
10380 struct btrfs_root *tree_root = fs_info->tree_root;
10381 struct btrfs_key key;
10382 struct inode *inode;
10383 struct kobject *kobj = NULL;
10387 struct btrfs_caching_control *caching_ctl = NULL;
10390 block_group = btrfs_lookup_block_group(fs_info, group_start);
10391 BUG_ON(!block_group);
10392 BUG_ON(!block_group->ro);
10395 * Free the reserved super bytes from this block group before
10398 free_excluded_extents(fs_info, block_group);
10399 btrfs_free_ref_tree_range(fs_info, block_group->key.objectid,
10400 block_group->key.offset);
10402 memcpy(&key, &block_group->key, sizeof(key));
10403 index = btrfs_bg_flags_to_raid_index(block_group->flags);
10404 if (block_group->flags & (BTRFS_BLOCK_GROUP_DUP |
10405 BTRFS_BLOCK_GROUP_RAID1 |
10406 BTRFS_BLOCK_GROUP_RAID10))
10411 /* make sure this block group isn't part of an allocation cluster */
10412 cluster = &fs_info->data_alloc_cluster;
10413 spin_lock(&cluster->refill_lock);
10414 btrfs_return_cluster_to_free_space(block_group, cluster);
10415 spin_unlock(&cluster->refill_lock);
10418 * make sure this block group isn't part of a metadata
10419 * allocation cluster
10421 cluster = &fs_info->meta_alloc_cluster;
10422 spin_lock(&cluster->refill_lock);
10423 btrfs_return_cluster_to_free_space(block_group, cluster);
10424 spin_unlock(&cluster->refill_lock);
10426 path = btrfs_alloc_path();
10433 * get the inode first so any iput calls done for the io_list
10434 * aren't the final iput (no unlinks allowed now)
10436 inode = lookup_free_space_inode(fs_info, block_group, path);
10438 mutex_lock(&trans->transaction->cache_write_mutex);
10440 * make sure our free spache cache IO is done before remove the
10443 spin_lock(&trans->transaction->dirty_bgs_lock);
10444 if (!list_empty(&block_group->io_list)) {
10445 list_del_init(&block_group->io_list);
10447 WARN_ON(!IS_ERR(inode) && inode != block_group->io_ctl.inode);
10449 spin_unlock(&trans->transaction->dirty_bgs_lock);
10450 btrfs_wait_cache_io(trans, block_group, path);
10451 btrfs_put_block_group(block_group);
10452 spin_lock(&trans->transaction->dirty_bgs_lock);
10455 if (!list_empty(&block_group->dirty_list)) {
10456 list_del_init(&block_group->dirty_list);
10457 btrfs_put_block_group(block_group);
10459 spin_unlock(&trans->transaction->dirty_bgs_lock);
10460 mutex_unlock(&trans->transaction->cache_write_mutex);
10462 if (!IS_ERR(inode)) {
10463 ret = btrfs_orphan_add(trans, BTRFS_I(inode));
10465 btrfs_add_delayed_iput(inode);
10468 clear_nlink(inode);
10469 /* One for the block groups ref */
10470 spin_lock(&block_group->lock);
10471 if (block_group->iref) {
10472 block_group->iref = 0;
10473 block_group->inode = NULL;
10474 spin_unlock(&block_group->lock);
10477 spin_unlock(&block_group->lock);
10479 /* One for our lookup ref */
10480 btrfs_add_delayed_iput(inode);
10483 key.objectid = BTRFS_FREE_SPACE_OBJECTID;
10484 key.offset = block_group->key.objectid;
10487 ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1);
10491 btrfs_release_path(path);
10493 ret = btrfs_del_item(trans, tree_root, path);
10496 btrfs_release_path(path);
10499 spin_lock(&fs_info->block_group_cache_lock);
10500 rb_erase(&block_group->cache_node,
10501 &fs_info->block_group_cache_tree);
10502 RB_CLEAR_NODE(&block_group->cache_node);
10504 if (fs_info->first_logical_byte == block_group->key.objectid)
10505 fs_info->first_logical_byte = (u64)-1;
10506 spin_unlock(&fs_info->block_group_cache_lock);
10508 down_write(&block_group->space_info->groups_sem);
10510 * we must use list_del_init so people can check to see if they
10511 * are still on the list after taking the semaphore
10513 list_del_init(&block_group->list);
10514 if (list_empty(&block_group->space_info->block_groups[index])) {
10515 kobj = block_group->space_info->block_group_kobjs[index];
10516 block_group->space_info->block_group_kobjs[index] = NULL;
10517 clear_avail_alloc_bits(fs_info, block_group->flags);
10519 up_write(&block_group->space_info->groups_sem);
10525 if (block_group->has_caching_ctl)
10526 caching_ctl = get_caching_control(block_group);
10527 if (block_group->cached == BTRFS_CACHE_STARTED)
10528 wait_block_group_cache_done(block_group);
10529 if (block_group->has_caching_ctl) {
10530 down_write(&fs_info->commit_root_sem);
10531 if (!caching_ctl) {
10532 struct btrfs_caching_control *ctl;
10534 list_for_each_entry(ctl,
10535 &fs_info->caching_block_groups, list)
10536 if (ctl->block_group == block_group) {
10538 refcount_inc(&caching_ctl->count);
10543 list_del_init(&caching_ctl->list);
10544 up_write(&fs_info->commit_root_sem);
10546 /* Once for the caching bgs list and once for us. */
10547 put_caching_control(caching_ctl);
10548 put_caching_control(caching_ctl);
10552 spin_lock(&trans->transaction->dirty_bgs_lock);
10553 if (!list_empty(&block_group->dirty_list)) {
10556 if (!list_empty(&block_group->io_list)) {
10559 spin_unlock(&trans->transaction->dirty_bgs_lock);
10560 btrfs_remove_free_space_cache(block_group);
10562 spin_lock(&block_group->space_info->lock);
10563 list_del_init(&block_group->ro_list);
10565 if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
10566 WARN_ON(block_group->space_info->total_bytes
10567 < block_group->key.offset);
10568 WARN_ON(block_group->space_info->bytes_readonly
10569 < block_group->key.offset);
10570 WARN_ON(block_group->space_info->disk_total
10571 < block_group->key.offset * factor);
10573 block_group->space_info->total_bytes -= block_group->key.offset;
10574 block_group->space_info->bytes_readonly -= block_group->key.offset;
10575 block_group->space_info->disk_total -= block_group->key.offset * factor;
10577 spin_unlock(&block_group->space_info->lock);
10579 memcpy(&key, &block_group->key, sizeof(key));
10581 mutex_lock(&fs_info->chunk_mutex);
10582 if (!list_empty(&em->list)) {
10583 /* We're in the transaction->pending_chunks list. */
10584 free_extent_map(em);
10586 spin_lock(&block_group->lock);
10587 block_group->removed = 1;
10589 * At this point trimming can't start on this block group, because we
10590 * removed the block group from the tree fs_info->block_group_cache_tree
10591 * so no one can't find it anymore and even if someone already got this
10592 * block group before we removed it from the rbtree, they have already
10593 * incremented block_group->trimming - if they didn't, they won't find
10594 * any free space entries because we already removed them all when we
10595 * called btrfs_remove_free_space_cache().
10597 * And we must not remove the extent map from the fs_info->mapping_tree
10598 * to prevent the same logical address range and physical device space
10599 * ranges from being reused for a new block group. This is because our
10600 * fs trim operation (btrfs_trim_fs() / btrfs_ioctl_fitrim()) is
10601 * completely transactionless, so while it is trimming a range the
10602 * currently running transaction might finish and a new one start,
10603 * allowing for new block groups to be created that can reuse the same
10604 * physical device locations unless we take this special care.
10606 * There may also be an implicit trim operation if the file system
10607 * is mounted with -odiscard. The same protections must remain
10608 * in place until the extents have been discarded completely when
10609 * the transaction commit has completed.
10611 remove_em = (atomic_read(&block_group->trimming) == 0);
10613 * Make sure a trimmer task always sees the em in the pinned_chunks list
10614 * if it sees block_group->removed == 1 (needs to lock block_group->lock
10615 * before checking block_group->removed).
10619 * Our em might be in trans->transaction->pending_chunks which
10620 * is protected by fs_info->chunk_mutex ([lock|unlock]_chunks),
10621 * and so is the fs_info->pinned_chunks list.
10623 * So at this point we must be holding the chunk_mutex to avoid
10624 * any races with chunk allocation (more specifically at
10625 * volumes.c:contains_pending_extent()), to ensure it always
10626 * sees the em, either in the pending_chunks list or in the
10627 * pinned_chunks list.
10629 list_move_tail(&em->list, &fs_info->pinned_chunks);
10631 spin_unlock(&block_group->lock);
10634 struct extent_map_tree *em_tree;
10636 em_tree = &fs_info->mapping_tree.map_tree;
10637 write_lock(&em_tree->lock);
10639 * The em might be in the pending_chunks list, so make sure the
10640 * chunk mutex is locked, since remove_extent_mapping() will
10641 * delete us from that list.
10643 remove_extent_mapping(em_tree, em);
10644 write_unlock(&em_tree->lock);
10645 /* once for the tree */
10646 free_extent_map(em);
10649 mutex_unlock(&fs_info->chunk_mutex);
10651 ret = remove_block_group_free_space(trans, fs_info, block_group);
10655 btrfs_put_block_group(block_group);
10656 btrfs_put_block_group(block_group);
10658 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
10664 ret = btrfs_del_item(trans, root, path);
10666 btrfs_free_path(path);
10670 struct btrfs_trans_handle *
10671 btrfs_start_trans_remove_block_group(struct btrfs_fs_info *fs_info,
10672 const u64 chunk_offset)
10674 struct extent_map_tree *em_tree = &fs_info->mapping_tree.map_tree;
10675 struct extent_map *em;
10676 struct map_lookup *map;
10677 unsigned int num_items;
10679 read_lock(&em_tree->lock);
10680 em = lookup_extent_mapping(em_tree, chunk_offset, 1);
10681 read_unlock(&em_tree->lock);
10682 ASSERT(em && em->start == chunk_offset);
10685 * We need to reserve 3 + N units from the metadata space info in order
10686 * to remove a block group (done at btrfs_remove_chunk() and at
10687 * btrfs_remove_block_group()), which are used for:
10689 * 1 unit for adding the free space inode's orphan (located in the tree
10691 * 1 unit for deleting the block group item (located in the extent
10693 * 1 unit for deleting the free space item (located in tree of tree
10695 * N units for deleting N device extent items corresponding to each
10696 * stripe (located in the device tree).
10698 * In order to remove a block group we also need to reserve units in the
10699 * system space info in order to update the chunk tree (update one or
10700 * more device items and remove one chunk item), but this is done at
10701 * btrfs_remove_chunk() through a call to check_system_chunk().
10703 map = em->map_lookup;
10704 num_items = 3 + map->num_stripes;
10705 free_extent_map(em);
10707 return btrfs_start_transaction_fallback_global_rsv(fs_info->extent_root,
10712 * Process the unused_bgs list and remove any that don't have any allocated
10713 * space inside of them.
10715 void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info)
10717 struct btrfs_block_group_cache *block_group;
10718 struct btrfs_space_info *space_info;
10719 struct btrfs_trans_handle *trans;
10722 if (!test_bit(BTRFS_FS_OPEN, &fs_info->flags))
10725 spin_lock(&fs_info->unused_bgs_lock);
10726 while (!list_empty(&fs_info->unused_bgs)) {
10730 block_group = list_first_entry(&fs_info->unused_bgs,
10731 struct btrfs_block_group_cache,
10733 list_del_init(&block_group->bg_list);
10735 space_info = block_group->space_info;
10737 if (ret || btrfs_mixed_space_info(space_info)) {
10738 btrfs_put_block_group(block_group);
10741 spin_unlock(&fs_info->unused_bgs_lock);
10743 mutex_lock(&fs_info->delete_unused_bgs_mutex);
10745 /* Don't want to race with allocators so take the groups_sem */
10746 down_write(&space_info->groups_sem);
10747 spin_lock(&block_group->lock);
10748 if (block_group->reserved ||
10749 btrfs_block_group_used(&block_group->item) ||
10751 list_is_singular(&block_group->list)) {
10753 * We want to bail if we made new allocations or have
10754 * outstanding allocations in this block group. We do
10755 * the ro check in case balance is currently acting on
10756 * this block group.
10758 spin_unlock(&block_group->lock);
10759 up_write(&space_info->groups_sem);
10762 spin_unlock(&block_group->lock);
10764 /* We don't want to force the issue, only flip if it's ok. */
10765 ret = inc_block_group_ro(block_group, 0);
10766 up_write(&space_info->groups_sem);
10773 * Want to do this before we do anything else so we can recover
10774 * properly if we fail to join the transaction.
10776 trans = btrfs_start_trans_remove_block_group(fs_info,
10777 block_group->key.objectid);
10778 if (IS_ERR(trans)) {
10779 btrfs_dec_block_group_ro(block_group);
10780 ret = PTR_ERR(trans);
10785 * We could have pending pinned extents for this block group,
10786 * just delete them, we don't care about them anymore.
10788 start = block_group->key.objectid;
10789 end = start + block_group->key.offset - 1;
10791 * Hold the unused_bg_unpin_mutex lock to avoid racing with
10792 * btrfs_finish_extent_commit(). If we are at transaction N,
10793 * another task might be running finish_extent_commit() for the
10794 * previous transaction N - 1, and have seen a range belonging
10795 * to the block group in freed_extents[] before we were able to
10796 * clear the whole block group range from freed_extents[]. This
10797 * means that task can lookup for the block group after we
10798 * unpinned it from freed_extents[] and removed it, leading to
10799 * a BUG_ON() at btrfs_unpin_extent_range().
10801 mutex_lock(&fs_info->unused_bg_unpin_mutex);
10802 ret = clear_extent_bits(&fs_info->freed_extents[0], start, end,
10805 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
10806 btrfs_dec_block_group_ro(block_group);
10809 ret = clear_extent_bits(&fs_info->freed_extents[1], start, end,
10812 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
10813 btrfs_dec_block_group_ro(block_group);
10816 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
10818 /* Reset pinned so btrfs_put_block_group doesn't complain */
10819 spin_lock(&space_info->lock);
10820 spin_lock(&block_group->lock);
10822 space_info->bytes_pinned -= block_group->pinned;
10823 space_info->bytes_readonly += block_group->pinned;
10824 percpu_counter_add(&space_info->total_bytes_pinned,
10825 -block_group->pinned);
10826 block_group->pinned = 0;
10828 spin_unlock(&block_group->lock);
10829 spin_unlock(&space_info->lock);
10831 /* DISCARD can flip during remount */
10832 trimming = btrfs_test_opt(fs_info, DISCARD);
10834 /* Implicit trim during transaction commit. */
10836 btrfs_get_block_group_trimming(block_group);
10839 * Btrfs_remove_chunk will abort the transaction if things go
10842 ret = btrfs_remove_chunk(trans, fs_info,
10843 block_group->key.objectid);
10847 btrfs_put_block_group_trimming(block_group);
10852 * If we're not mounted with -odiscard, we can just forget
10853 * about this block group. Otherwise we'll need to wait
10854 * until transaction commit to do the actual discard.
10857 spin_lock(&fs_info->unused_bgs_lock);
10859 * A concurrent scrub might have added us to the list
10860 * fs_info->unused_bgs, so use a list_move operation
10861 * to add the block group to the deleted_bgs list.
10863 list_move(&block_group->bg_list,
10864 &trans->transaction->deleted_bgs);
10865 spin_unlock(&fs_info->unused_bgs_lock);
10866 btrfs_get_block_group(block_group);
10869 btrfs_end_transaction(trans);
10871 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
10872 btrfs_put_block_group(block_group);
10873 spin_lock(&fs_info->unused_bgs_lock);
10875 spin_unlock(&fs_info->unused_bgs_lock);
10878 int btrfs_init_space_info(struct btrfs_fs_info *fs_info)
10880 struct btrfs_space_info *space_info;
10881 struct btrfs_super_block *disk_super;
10887 disk_super = fs_info->super_copy;
10888 if (!btrfs_super_root(disk_super))
10891 features = btrfs_super_incompat_flags(disk_super);
10892 if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
10895 flags = BTRFS_BLOCK_GROUP_SYSTEM;
10896 ret = create_space_info(fs_info, flags, &space_info);
10901 flags = BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA;
10902 ret = create_space_info(fs_info, flags, &space_info);
10904 flags = BTRFS_BLOCK_GROUP_METADATA;
10905 ret = create_space_info(fs_info, flags, &space_info);
10909 flags = BTRFS_BLOCK_GROUP_DATA;
10910 ret = create_space_info(fs_info, flags, &space_info);
10916 int btrfs_error_unpin_extent_range(struct btrfs_fs_info *fs_info,
10917 u64 start, u64 end)
10919 return unpin_extent_range(fs_info, start, end, false);
10923 * It used to be that old block groups would be left around forever.
10924 * Iterating over them would be enough to trim unused space. Since we
10925 * now automatically remove them, we also need to iterate over unallocated
10928 * We don't want a transaction for this since the discard may take a
10929 * substantial amount of time. We don't require that a transaction be
10930 * running, but we do need to take a running transaction into account
10931 * to ensure that we're not discarding chunks that were released in
10932 * the current transaction.
10934 * Holding the chunks lock will prevent other threads from allocating
10935 * or releasing chunks, but it won't prevent a running transaction
10936 * from committing and releasing the memory that the pending chunks
10937 * list head uses. For that, we need to take a reference to the
10940 static int btrfs_trim_free_extents(struct btrfs_device *device,
10941 u64 minlen, u64 *trimmed)
10943 u64 start = 0, len = 0;
10948 /* Not writeable = nothing to do. */
10949 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state))
10952 /* No free space = nothing to do. */
10953 if (device->total_bytes <= device->bytes_used)
10959 struct btrfs_fs_info *fs_info = device->fs_info;
10960 struct btrfs_transaction *trans;
10963 ret = mutex_lock_interruptible(&fs_info->chunk_mutex);
10967 down_read(&fs_info->commit_root_sem);
10969 spin_lock(&fs_info->trans_lock);
10970 trans = fs_info->running_transaction;
10972 refcount_inc(&trans->use_count);
10973 spin_unlock(&fs_info->trans_lock);
10975 ret = find_free_dev_extent_start(trans, device, minlen, start,
10978 btrfs_put_transaction(trans);
10981 up_read(&fs_info->commit_root_sem);
10982 mutex_unlock(&fs_info->chunk_mutex);
10983 if (ret == -ENOSPC)
10988 ret = btrfs_issue_discard(device->bdev, start, len, &bytes);
10989 up_read(&fs_info->commit_root_sem);
10990 mutex_unlock(&fs_info->chunk_mutex);
10998 if (fatal_signal_pending(current)) {
10999 ret = -ERESTARTSYS;
11009 int btrfs_trim_fs(struct btrfs_fs_info *fs_info, struct fstrim_range *range)
11011 struct btrfs_block_group_cache *cache = NULL;
11012 struct btrfs_device *device;
11013 struct list_head *devices;
11018 u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
11022 * try to trim all FS space, our block group may start from non-zero.
11024 if (range->len == total_bytes)
11025 cache = btrfs_lookup_first_block_group(fs_info, range->start);
11027 cache = btrfs_lookup_block_group(fs_info, range->start);
11030 if (cache->key.objectid >= (range->start + range->len)) {
11031 btrfs_put_block_group(cache);
11035 start = max(range->start, cache->key.objectid);
11036 end = min(range->start + range->len,
11037 cache->key.objectid + cache->key.offset);
11039 if (end - start >= range->minlen) {
11040 if (!block_group_cache_done(cache)) {
11041 ret = cache_block_group(cache, 0);
11043 btrfs_put_block_group(cache);
11046 ret = wait_block_group_cache_done(cache);
11048 btrfs_put_block_group(cache);
11052 ret = btrfs_trim_block_group(cache,
11058 trimmed += group_trimmed;
11060 btrfs_put_block_group(cache);
11065 cache = next_block_group(fs_info, cache);
11068 mutex_lock(&fs_info->fs_devices->device_list_mutex);
11069 devices = &fs_info->fs_devices->alloc_list;
11070 list_for_each_entry(device, devices, dev_alloc_list) {
11071 ret = btrfs_trim_free_extents(device, range->minlen,
11076 trimmed += group_trimmed;
11078 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
11080 range->len = trimmed;
11085 * btrfs_{start,end}_write_no_snapshotting() are similar to
11086 * mnt_{want,drop}_write(), they are used to prevent some tasks from writing
11087 * data into the page cache through nocow before the subvolume is snapshoted,
11088 * but flush the data into disk after the snapshot creation, or to prevent
11089 * operations while snapshotting is ongoing and that cause the snapshot to be
11090 * inconsistent (writes followed by expanding truncates for example).
11092 void btrfs_end_write_no_snapshotting(struct btrfs_root *root)
11094 percpu_counter_dec(&root->subv_writers->counter);
11096 * Make sure counter is updated before we wake up waiters.
11099 if (waitqueue_active(&root->subv_writers->wait))
11100 wake_up(&root->subv_writers->wait);
11103 int btrfs_start_write_no_snapshotting(struct btrfs_root *root)
11105 if (atomic_read(&root->will_be_snapshotted))
11108 percpu_counter_inc(&root->subv_writers->counter);
11110 * Make sure counter is updated before we check for snapshot creation.
11113 if (atomic_read(&root->will_be_snapshotted)) {
11114 btrfs_end_write_no_snapshotting(root);
11120 void btrfs_wait_for_snapshot_creation(struct btrfs_root *root)
11125 ret = btrfs_start_write_no_snapshotting(root);
11128 wait_var_event(&root->will_be_snapshotted,
11129 !atomic_read(&root->will_be_snapshotted));