1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (C) 2007 Oracle. All rights reserved.
6 #include <linux/sched.h>
7 #include <linux/sched/signal.h>
8 #include <linux/pagemap.h>
9 #include <linux/writeback.h>
10 #include <linux/blkdev.h>
11 #include <linux/sort.h>
12 #include <linux/rcupdate.h>
13 #include <linux/kthread.h>
14 #include <linux/slab.h>
15 #include <linux/ratelimit.h>
16 #include <linux/percpu_counter.h>
17 #include <linux/lockdep.h>
18 #include <linux/crc32c.h>
21 #include "print-tree.h"
25 #include "free-space-cache.h"
26 #include "free-space-tree.h"
30 #include "ref-verify.h"
32 #undef SCRAMBLE_DELAYED_REFS
35 * control flags for do_chunk_alloc's force field
36 * CHUNK_ALLOC_NO_FORCE means to only allocate a chunk
37 * if we really need one.
39 * CHUNK_ALLOC_LIMITED means to only try and allocate one
40 * if we have very few chunks already allocated. This is
41 * used as part of the clustering code to help make sure
42 * we have a good pool of storage to cluster in, without
43 * filling the FS with empty chunks
45 * CHUNK_ALLOC_FORCE means it must try to allocate one
49 CHUNK_ALLOC_NO_FORCE = 0,
50 CHUNK_ALLOC_LIMITED = 1,
51 CHUNK_ALLOC_FORCE = 2,
55 * Declare a helper function to detect underflow of various space info members
57 #define DECLARE_SPACE_INFO_UPDATE(name) \
58 static inline void update_##name(struct btrfs_space_info *sinfo, \
61 if (bytes < 0 && sinfo->name < -bytes) { \
66 sinfo->name += bytes; \
69 DECLARE_SPACE_INFO_UPDATE(bytes_may_use);
70 DECLARE_SPACE_INFO_UPDATE(bytes_pinned);
72 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
73 struct btrfs_delayed_ref_node *node, u64 parent,
74 u64 root_objectid, u64 owner_objectid,
75 u64 owner_offset, int refs_to_drop,
76 struct btrfs_delayed_extent_op *extra_op);
77 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
78 struct extent_buffer *leaf,
79 struct btrfs_extent_item *ei);
80 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
81 u64 parent, u64 root_objectid,
82 u64 flags, u64 owner, u64 offset,
83 struct btrfs_key *ins, int ref_mod);
84 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
85 struct btrfs_delayed_ref_node *node,
86 struct btrfs_delayed_extent_op *extent_op);
87 static int do_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
89 static int find_next_key(struct btrfs_path *path, int level,
90 struct btrfs_key *key);
91 static void dump_space_info(struct btrfs_fs_info *fs_info,
92 struct btrfs_space_info *info, u64 bytes,
93 int dump_block_groups);
94 static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
96 static void space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
97 struct btrfs_space_info *space_info,
99 static void space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
100 struct btrfs_space_info *space_info,
104 block_group_cache_done(struct btrfs_block_group_cache *cache)
107 return cache->cached == BTRFS_CACHE_FINISHED ||
108 cache->cached == BTRFS_CACHE_ERROR;
111 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
113 return (cache->flags & bits) == bits;
116 void btrfs_get_block_group(struct btrfs_block_group_cache *cache)
118 atomic_inc(&cache->count);
121 void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
123 if (atomic_dec_and_test(&cache->count)) {
124 WARN_ON(cache->pinned > 0);
125 WARN_ON(cache->reserved > 0);
128 * If not empty, someone is still holding mutex of
129 * full_stripe_lock, which can only be released by caller.
130 * And it will definitely cause use-after-free when caller
131 * tries to release full stripe lock.
133 * No better way to resolve, but only to warn.
135 WARN_ON(!RB_EMPTY_ROOT(&cache->full_stripe_locks_root.root));
136 kfree(cache->free_space_ctl);
142 * this adds the block group to the fs_info rb tree for the block group
145 static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
146 struct btrfs_block_group_cache *block_group)
149 struct rb_node *parent = NULL;
150 struct btrfs_block_group_cache *cache;
152 spin_lock(&info->block_group_cache_lock);
153 p = &info->block_group_cache_tree.rb_node;
157 cache = rb_entry(parent, struct btrfs_block_group_cache,
159 if (block_group->key.objectid < cache->key.objectid) {
161 } else if (block_group->key.objectid > cache->key.objectid) {
164 spin_unlock(&info->block_group_cache_lock);
169 rb_link_node(&block_group->cache_node, parent, p);
170 rb_insert_color(&block_group->cache_node,
171 &info->block_group_cache_tree);
173 if (info->first_logical_byte > block_group->key.objectid)
174 info->first_logical_byte = block_group->key.objectid;
176 spin_unlock(&info->block_group_cache_lock);
182 * This will return the block group at or after bytenr if contains is 0, else
183 * it will return the block group that contains the bytenr
185 static struct btrfs_block_group_cache *
186 block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
189 struct btrfs_block_group_cache *cache, *ret = NULL;
193 spin_lock(&info->block_group_cache_lock);
194 n = info->block_group_cache_tree.rb_node;
197 cache = rb_entry(n, struct btrfs_block_group_cache,
199 end = cache->key.objectid + cache->key.offset - 1;
200 start = cache->key.objectid;
202 if (bytenr < start) {
203 if (!contains && (!ret || start < ret->key.objectid))
206 } else if (bytenr > start) {
207 if (contains && bytenr <= end) {
218 btrfs_get_block_group(ret);
219 if (bytenr == 0 && info->first_logical_byte > ret->key.objectid)
220 info->first_logical_byte = ret->key.objectid;
222 spin_unlock(&info->block_group_cache_lock);
227 static int add_excluded_extent(struct btrfs_fs_info *fs_info,
228 u64 start, u64 num_bytes)
230 u64 end = start + num_bytes - 1;
231 set_extent_bits(&fs_info->freed_extents[0],
232 start, end, EXTENT_UPTODATE);
233 set_extent_bits(&fs_info->freed_extents[1],
234 start, end, EXTENT_UPTODATE);
238 static void free_excluded_extents(struct btrfs_block_group_cache *cache)
240 struct btrfs_fs_info *fs_info = cache->fs_info;
243 start = cache->key.objectid;
244 end = start + cache->key.offset - 1;
246 clear_extent_bits(&fs_info->freed_extents[0],
247 start, end, EXTENT_UPTODATE);
248 clear_extent_bits(&fs_info->freed_extents[1],
249 start, end, EXTENT_UPTODATE);
252 static int exclude_super_stripes(struct btrfs_block_group_cache *cache)
254 struct btrfs_fs_info *fs_info = cache->fs_info;
260 if (cache->key.objectid < BTRFS_SUPER_INFO_OFFSET) {
261 stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->key.objectid;
262 cache->bytes_super += stripe_len;
263 ret = add_excluded_extent(fs_info, cache->key.objectid,
269 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
270 bytenr = btrfs_sb_offset(i);
271 ret = btrfs_rmap_block(fs_info, cache->key.objectid,
272 bytenr, &logical, &nr, &stripe_len);
279 if (logical[nr] > cache->key.objectid +
283 if (logical[nr] + stripe_len <= cache->key.objectid)
287 if (start < cache->key.objectid) {
288 start = cache->key.objectid;
289 len = (logical[nr] + stripe_len) - start;
291 len = min_t(u64, stripe_len,
292 cache->key.objectid +
293 cache->key.offset - start);
296 cache->bytes_super += len;
297 ret = add_excluded_extent(fs_info, start, len);
309 static struct btrfs_caching_control *
310 get_caching_control(struct btrfs_block_group_cache *cache)
312 struct btrfs_caching_control *ctl;
314 spin_lock(&cache->lock);
315 if (!cache->caching_ctl) {
316 spin_unlock(&cache->lock);
320 ctl = cache->caching_ctl;
321 refcount_inc(&ctl->count);
322 spin_unlock(&cache->lock);
326 static void put_caching_control(struct btrfs_caching_control *ctl)
328 if (refcount_dec_and_test(&ctl->count))
332 #ifdef CONFIG_BTRFS_DEBUG
333 static void fragment_free_space(struct btrfs_block_group_cache *block_group)
335 struct btrfs_fs_info *fs_info = block_group->fs_info;
336 u64 start = block_group->key.objectid;
337 u64 len = block_group->key.offset;
338 u64 chunk = block_group->flags & BTRFS_BLOCK_GROUP_METADATA ?
339 fs_info->nodesize : fs_info->sectorsize;
340 u64 step = chunk << 1;
342 while (len > chunk) {
343 btrfs_remove_free_space(block_group, start, chunk);
354 * this is only called by cache_block_group, since we could have freed extents
355 * we need to check the pinned_extents for any extents that can't be used yet
356 * since their free space will be released as soon as the transaction commits.
358 u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
361 struct btrfs_fs_info *info = block_group->fs_info;
362 u64 extent_start, extent_end, size, total_added = 0;
365 while (start < end) {
366 ret = find_first_extent_bit(info->pinned_extents, start,
367 &extent_start, &extent_end,
368 EXTENT_DIRTY | EXTENT_UPTODATE,
373 if (extent_start <= start) {
374 start = extent_end + 1;
375 } else if (extent_start > start && extent_start < end) {
376 size = extent_start - start;
378 ret = btrfs_add_free_space(block_group, start,
380 BUG_ON(ret); /* -ENOMEM or logic error */
381 start = extent_end + 1;
390 ret = btrfs_add_free_space(block_group, start, size);
391 BUG_ON(ret); /* -ENOMEM or logic error */
397 static int load_extent_tree_free(struct btrfs_caching_control *caching_ctl)
399 struct btrfs_block_group_cache *block_group = caching_ctl->block_group;
400 struct btrfs_fs_info *fs_info = block_group->fs_info;
401 struct btrfs_root *extent_root = fs_info->extent_root;
402 struct btrfs_path *path;
403 struct extent_buffer *leaf;
404 struct btrfs_key key;
411 path = btrfs_alloc_path();
415 last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
417 #ifdef CONFIG_BTRFS_DEBUG
419 * If we're fragmenting we don't want to make anybody think we can
420 * allocate from this block group until we've had a chance to fragment
423 if (btrfs_should_fragment_free_space(block_group))
427 * We don't want to deadlock with somebody trying to allocate a new
428 * extent for the extent root while also trying to search the extent
429 * root to add free space. So we skip locking and search the commit
430 * root, since its read-only
432 path->skip_locking = 1;
433 path->search_commit_root = 1;
434 path->reada = READA_FORWARD;
438 key.type = BTRFS_EXTENT_ITEM_KEY;
441 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
445 leaf = path->nodes[0];
446 nritems = btrfs_header_nritems(leaf);
449 if (btrfs_fs_closing(fs_info) > 1) {
454 if (path->slots[0] < nritems) {
455 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
457 ret = find_next_key(path, 0, &key);
461 if (need_resched() ||
462 rwsem_is_contended(&fs_info->commit_root_sem)) {
464 caching_ctl->progress = last;
465 btrfs_release_path(path);
466 up_read(&fs_info->commit_root_sem);
467 mutex_unlock(&caching_ctl->mutex);
469 mutex_lock(&caching_ctl->mutex);
470 down_read(&fs_info->commit_root_sem);
474 ret = btrfs_next_leaf(extent_root, path);
479 leaf = path->nodes[0];
480 nritems = btrfs_header_nritems(leaf);
484 if (key.objectid < last) {
487 key.type = BTRFS_EXTENT_ITEM_KEY;
490 caching_ctl->progress = last;
491 btrfs_release_path(path);
495 if (key.objectid < block_group->key.objectid) {
500 if (key.objectid >= block_group->key.objectid +
501 block_group->key.offset)
504 if (key.type == BTRFS_EXTENT_ITEM_KEY ||
505 key.type == BTRFS_METADATA_ITEM_KEY) {
506 total_found += add_new_free_space(block_group, last,
508 if (key.type == BTRFS_METADATA_ITEM_KEY)
509 last = key.objectid +
512 last = key.objectid + key.offset;
514 if (total_found > CACHING_CTL_WAKE_UP) {
517 wake_up(&caching_ctl->wait);
524 total_found += add_new_free_space(block_group, last,
525 block_group->key.objectid +
526 block_group->key.offset);
527 caching_ctl->progress = (u64)-1;
530 btrfs_free_path(path);
534 static noinline void caching_thread(struct btrfs_work *work)
536 struct btrfs_block_group_cache *block_group;
537 struct btrfs_fs_info *fs_info;
538 struct btrfs_caching_control *caching_ctl;
541 caching_ctl = container_of(work, struct btrfs_caching_control, work);
542 block_group = caching_ctl->block_group;
543 fs_info = block_group->fs_info;
545 mutex_lock(&caching_ctl->mutex);
546 down_read(&fs_info->commit_root_sem);
548 if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE))
549 ret = load_free_space_tree(caching_ctl);
551 ret = load_extent_tree_free(caching_ctl);
553 spin_lock(&block_group->lock);
554 block_group->caching_ctl = NULL;
555 block_group->cached = ret ? BTRFS_CACHE_ERROR : BTRFS_CACHE_FINISHED;
556 spin_unlock(&block_group->lock);
558 #ifdef CONFIG_BTRFS_DEBUG
559 if (btrfs_should_fragment_free_space(block_group)) {
562 spin_lock(&block_group->space_info->lock);
563 spin_lock(&block_group->lock);
564 bytes_used = block_group->key.offset -
565 btrfs_block_group_used(&block_group->item);
566 block_group->space_info->bytes_used += bytes_used >> 1;
567 spin_unlock(&block_group->lock);
568 spin_unlock(&block_group->space_info->lock);
569 fragment_free_space(block_group);
573 caching_ctl->progress = (u64)-1;
575 up_read(&fs_info->commit_root_sem);
576 free_excluded_extents(block_group);
577 mutex_unlock(&caching_ctl->mutex);
579 wake_up(&caching_ctl->wait);
581 put_caching_control(caching_ctl);
582 btrfs_put_block_group(block_group);
585 static int cache_block_group(struct btrfs_block_group_cache *cache,
589 struct btrfs_fs_info *fs_info = cache->fs_info;
590 struct btrfs_caching_control *caching_ctl;
593 caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_NOFS);
597 INIT_LIST_HEAD(&caching_ctl->list);
598 mutex_init(&caching_ctl->mutex);
599 init_waitqueue_head(&caching_ctl->wait);
600 caching_ctl->block_group = cache;
601 caching_ctl->progress = cache->key.objectid;
602 refcount_set(&caching_ctl->count, 1);
603 btrfs_init_work(&caching_ctl->work, btrfs_cache_helper,
604 caching_thread, NULL, NULL);
606 spin_lock(&cache->lock);
608 * This should be a rare occasion, but this could happen I think in the
609 * case where one thread starts to load the space cache info, and then
610 * some other thread starts a transaction commit which tries to do an
611 * allocation while the other thread is still loading the space cache
612 * info. The previous loop should have kept us from choosing this block
613 * group, but if we've moved to the state where we will wait on caching
614 * block groups we need to first check if we're doing a fast load here,
615 * so we can wait for it to finish, otherwise we could end up allocating
616 * from a block group who's cache gets evicted for one reason or
619 while (cache->cached == BTRFS_CACHE_FAST) {
620 struct btrfs_caching_control *ctl;
622 ctl = cache->caching_ctl;
623 refcount_inc(&ctl->count);
624 prepare_to_wait(&ctl->wait, &wait, TASK_UNINTERRUPTIBLE);
625 spin_unlock(&cache->lock);
629 finish_wait(&ctl->wait, &wait);
630 put_caching_control(ctl);
631 spin_lock(&cache->lock);
634 if (cache->cached != BTRFS_CACHE_NO) {
635 spin_unlock(&cache->lock);
639 WARN_ON(cache->caching_ctl);
640 cache->caching_ctl = caching_ctl;
641 cache->cached = BTRFS_CACHE_FAST;
642 spin_unlock(&cache->lock);
644 if (btrfs_test_opt(fs_info, SPACE_CACHE)) {
645 mutex_lock(&caching_ctl->mutex);
646 ret = load_free_space_cache(fs_info, cache);
648 spin_lock(&cache->lock);
650 cache->caching_ctl = NULL;
651 cache->cached = BTRFS_CACHE_FINISHED;
652 cache->last_byte_to_unpin = (u64)-1;
653 caching_ctl->progress = (u64)-1;
655 if (load_cache_only) {
656 cache->caching_ctl = NULL;
657 cache->cached = BTRFS_CACHE_NO;
659 cache->cached = BTRFS_CACHE_STARTED;
660 cache->has_caching_ctl = 1;
663 spin_unlock(&cache->lock);
664 #ifdef CONFIG_BTRFS_DEBUG
666 btrfs_should_fragment_free_space(cache)) {
669 spin_lock(&cache->space_info->lock);
670 spin_lock(&cache->lock);
671 bytes_used = cache->key.offset -
672 btrfs_block_group_used(&cache->item);
673 cache->space_info->bytes_used += bytes_used >> 1;
674 spin_unlock(&cache->lock);
675 spin_unlock(&cache->space_info->lock);
676 fragment_free_space(cache);
679 mutex_unlock(&caching_ctl->mutex);
681 wake_up(&caching_ctl->wait);
683 put_caching_control(caching_ctl);
684 free_excluded_extents(cache);
689 * We're either using the free space tree or no caching at all.
690 * Set cached to the appropriate value and wakeup any waiters.
692 spin_lock(&cache->lock);
693 if (load_cache_only) {
694 cache->caching_ctl = NULL;
695 cache->cached = BTRFS_CACHE_NO;
697 cache->cached = BTRFS_CACHE_STARTED;
698 cache->has_caching_ctl = 1;
700 spin_unlock(&cache->lock);
701 wake_up(&caching_ctl->wait);
704 if (load_cache_only) {
705 put_caching_control(caching_ctl);
709 down_write(&fs_info->commit_root_sem);
710 refcount_inc(&caching_ctl->count);
711 list_add_tail(&caching_ctl->list, &fs_info->caching_block_groups);
712 up_write(&fs_info->commit_root_sem);
714 btrfs_get_block_group(cache);
716 btrfs_queue_work(fs_info->caching_workers, &caching_ctl->work);
722 * return the block group that starts at or after bytenr
724 static struct btrfs_block_group_cache *
725 btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr)
727 return block_group_cache_tree_search(info, bytenr, 0);
731 * return the block group that contains the given bytenr
733 struct btrfs_block_group_cache *btrfs_lookup_block_group(
734 struct btrfs_fs_info *info,
737 return block_group_cache_tree_search(info, bytenr, 1);
740 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
743 struct list_head *head = &info->space_info;
744 struct btrfs_space_info *found;
746 flags &= BTRFS_BLOCK_GROUP_TYPE_MASK;
749 list_for_each_entry_rcu(found, head, list) {
750 if (found->flags & flags) {
759 static void add_pinned_bytes(struct btrfs_fs_info *fs_info, s64 num_bytes,
760 bool metadata, u64 root_objectid)
762 struct btrfs_space_info *space_info;
766 if (root_objectid == BTRFS_CHUNK_TREE_OBJECTID)
767 flags = BTRFS_BLOCK_GROUP_SYSTEM;
769 flags = BTRFS_BLOCK_GROUP_METADATA;
771 flags = BTRFS_BLOCK_GROUP_DATA;
774 space_info = __find_space_info(fs_info, flags);
776 percpu_counter_add_batch(&space_info->total_bytes_pinned, num_bytes,
777 BTRFS_TOTAL_BYTES_PINNED_BATCH);
781 * after adding space to the filesystem, we need to clear the full flags
782 * on all the space infos.
784 void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
786 struct list_head *head = &info->space_info;
787 struct btrfs_space_info *found;
790 list_for_each_entry_rcu(found, head, list)
795 /* simple helper to search for an existing data extent at a given offset */
796 int btrfs_lookup_data_extent(struct btrfs_fs_info *fs_info, u64 start, u64 len)
799 struct btrfs_key key;
800 struct btrfs_path *path;
802 path = btrfs_alloc_path();
806 key.objectid = start;
808 key.type = BTRFS_EXTENT_ITEM_KEY;
809 ret = btrfs_search_slot(NULL, fs_info->extent_root, &key, path, 0, 0);
810 btrfs_free_path(path);
815 * helper function to lookup reference count and flags of a tree block.
817 * the head node for delayed ref is used to store the sum of all the
818 * reference count modifications queued up in the rbtree. the head
819 * node may also store the extent flags to set. This way you can check
820 * to see what the reference count and extent flags would be if all of
821 * the delayed refs are not processed.
823 int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
824 struct btrfs_fs_info *fs_info, u64 bytenr,
825 u64 offset, int metadata, u64 *refs, u64 *flags)
827 struct btrfs_delayed_ref_head *head;
828 struct btrfs_delayed_ref_root *delayed_refs;
829 struct btrfs_path *path;
830 struct btrfs_extent_item *ei;
831 struct extent_buffer *leaf;
832 struct btrfs_key key;
839 * If we don't have skinny metadata, don't bother doing anything
842 if (metadata && !btrfs_fs_incompat(fs_info, SKINNY_METADATA)) {
843 offset = fs_info->nodesize;
847 path = btrfs_alloc_path();
852 path->skip_locking = 1;
853 path->search_commit_root = 1;
857 key.objectid = bytenr;
860 key.type = BTRFS_METADATA_ITEM_KEY;
862 key.type = BTRFS_EXTENT_ITEM_KEY;
864 ret = btrfs_search_slot(trans, fs_info->extent_root, &key, path, 0, 0);
868 if (ret > 0 && metadata && key.type == BTRFS_METADATA_ITEM_KEY) {
869 if (path->slots[0]) {
871 btrfs_item_key_to_cpu(path->nodes[0], &key,
873 if (key.objectid == bytenr &&
874 key.type == BTRFS_EXTENT_ITEM_KEY &&
875 key.offset == fs_info->nodesize)
881 leaf = path->nodes[0];
882 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
883 if (item_size >= sizeof(*ei)) {
884 ei = btrfs_item_ptr(leaf, path->slots[0],
885 struct btrfs_extent_item);
886 num_refs = btrfs_extent_refs(leaf, ei);
887 extent_flags = btrfs_extent_flags(leaf, ei);
890 btrfs_print_v0_err(fs_info);
892 btrfs_abort_transaction(trans, ret);
894 btrfs_handle_fs_error(fs_info, ret, NULL);
899 BUG_ON(num_refs == 0);
909 delayed_refs = &trans->transaction->delayed_refs;
910 spin_lock(&delayed_refs->lock);
911 head = btrfs_find_delayed_ref_head(delayed_refs, bytenr);
913 if (!mutex_trylock(&head->mutex)) {
914 refcount_inc(&head->refs);
915 spin_unlock(&delayed_refs->lock);
917 btrfs_release_path(path);
920 * Mutex was contended, block until it's released and try
923 mutex_lock(&head->mutex);
924 mutex_unlock(&head->mutex);
925 btrfs_put_delayed_ref_head(head);
928 spin_lock(&head->lock);
929 if (head->extent_op && head->extent_op->update_flags)
930 extent_flags |= head->extent_op->flags_to_set;
932 BUG_ON(num_refs == 0);
934 num_refs += head->ref_mod;
935 spin_unlock(&head->lock);
936 mutex_unlock(&head->mutex);
938 spin_unlock(&delayed_refs->lock);
940 WARN_ON(num_refs == 0);
944 *flags = extent_flags;
946 btrfs_free_path(path);
951 * Back reference rules. Back refs have three main goals:
953 * 1) differentiate between all holders of references to an extent so that
954 * when a reference is dropped we can make sure it was a valid reference
955 * before freeing the extent.
957 * 2) Provide enough information to quickly find the holders of an extent
958 * if we notice a given block is corrupted or bad.
960 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
961 * maintenance. This is actually the same as #2, but with a slightly
962 * different use case.
964 * There are two kinds of back refs. The implicit back refs is optimized
965 * for pointers in non-shared tree blocks. For a given pointer in a block,
966 * back refs of this kind provide information about the block's owner tree
967 * and the pointer's key. These information allow us to find the block by
968 * b-tree searching. The full back refs is for pointers in tree blocks not
969 * referenced by their owner trees. The location of tree block is recorded
970 * in the back refs. Actually the full back refs is generic, and can be
971 * used in all cases the implicit back refs is used. The major shortcoming
972 * of the full back refs is its overhead. Every time a tree block gets
973 * COWed, we have to update back refs entry for all pointers in it.
975 * For a newly allocated tree block, we use implicit back refs for
976 * pointers in it. This means most tree related operations only involve
977 * implicit back refs. For a tree block created in old transaction, the
978 * only way to drop a reference to it is COW it. So we can detect the
979 * event that tree block loses its owner tree's reference and do the
980 * back refs conversion.
982 * When a tree block is COWed through a tree, there are four cases:
984 * The reference count of the block is one and the tree is the block's
985 * owner tree. Nothing to do in this case.
987 * The reference count of the block is one and the tree is not the
988 * block's owner tree. In this case, full back refs is used for pointers
989 * in the block. Remove these full back refs, add implicit back refs for
990 * every pointers in the new block.
992 * The reference count of the block is greater than one and the tree is
993 * the block's owner tree. In this case, implicit back refs is used for
994 * pointers in the block. Add full back refs for every pointers in the
995 * block, increase lower level extents' reference counts. The original
996 * implicit back refs are entailed to the new block.
998 * The reference count of the block is greater than one and the tree is
999 * not the block's owner tree. Add implicit back refs for every pointer in
1000 * the new block, increase lower level extents' reference count.
1002 * Back Reference Key composing:
1004 * The key objectid corresponds to the first byte in the extent,
1005 * The key type is used to differentiate between types of back refs.
1006 * There are different meanings of the key offset for different types
1009 * File extents can be referenced by:
1011 * - multiple snapshots, subvolumes, or different generations in one subvol
1012 * - different files inside a single subvolume
1013 * - different offsets inside a file (bookend extents in file.c)
1015 * The extent ref structure for the implicit back refs has fields for:
1017 * - Objectid of the subvolume root
1018 * - objectid of the file holding the reference
1019 * - original offset in the file
1020 * - how many bookend extents
1022 * The key offset for the implicit back refs is hash of the first
1025 * The extent ref structure for the full back refs has field for:
1027 * - number of pointers in the tree leaf
1029 * The key offset for the implicit back refs is the first byte of
1032 * When a file extent is allocated, The implicit back refs is used.
1033 * the fields are filled in:
1035 * (root_key.objectid, inode objectid, offset in file, 1)
1037 * When a file extent is removed file truncation, we find the
1038 * corresponding implicit back refs and check the following fields:
1040 * (btrfs_header_owner(leaf), inode objectid, offset in file)
1042 * Btree extents can be referenced by:
1044 * - Different subvolumes
1046 * Both the implicit back refs and the full back refs for tree blocks
1047 * only consist of key. The key offset for the implicit back refs is
1048 * objectid of block's owner tree. The key offset for the full back refs
1049 * is the first byte of parent block.
1051 * When implicit back refs is used, information about the lowest key and
1052 * level of the tree block are required. These information are stored in
1053 * tree block info structure.
1057 * is_data == BTRFS_REF_TYPE_BLOCK, tree block type is required,
1058 * is_data == BTRFS_REF_TYPE_DATA, data type is requiried,
1059 * is_data == BTRFS_REF_TYPE_ANY, either type is OK.
1061 int btrfs_get_extent_inline_ref_type(const struct extent_buffer *eb,
1062 struct btrfs_extent_inline_ref *iref,
1063 enum btrfs_inline_ref_type is_data)
1065 int type = btrfs_extent_inline_ref_type(eb, iref);
1066 u64 offset = btrfs_extent_inline_ref_offset(eb, iref);
1068 if (type == BTRFS_TREE_BLOCK_REF_KEY ||
1069 type == BTRFS_SHARED_BLOCK_REF_KEY ||
1070 type == BTRFS_SHARED_DATA_REF_KEY ||
1071 type == BTRFS_EXTENT_DATA_REF_KEY) {
1072 if (is_data == BTRFS_REF_TYPE_BLOCK) {
1073 if (type == BTRFS_TREE_BLOCK_REF_KEY)
1075 if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1076 ASSERT(eb->fs_info);
1078 * Every shared one has parent tree
1079 * block, which must be aligned to
1083 IS_ALIGNED(offset, eb->fs_info->nodesize))
1086 } else if (is_data == BTRFS_REF_TYPE_DATA) {
1087 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1089 if (type == BTRFS_SHARED_DATA_REF_KEY) {
1090 ASSERT(eb->fs_info);
1092 * Every shared one has parent tree
1093 * block, which must be aligned to
1097 IS_ALIGNED(offset, eb->fs_info->nodesize))
1101 ASSERT(is_data == BTRFS_REF_TYPE_ANY);
1106 btrfs_print_leaf((struct extent_buffer *)eb);
1107 btrfs_err(eb->fs_info, "eb %llu invalid extent inline ref type %d",
1111 return BTRFS_REF_TYPE_INVALID;
1114 static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
1116 u32 high_crc = ~(u32)0;
1117 u32 low_crc = ~(u32)0;
1120 lenum = cpu_to_le64(root_objectid);
1121 high_crc = crc32c(high_crc, &lenum, sizeof(lenum));
1122 lenum = cpu_to_le64(owner);
1123 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
1124 lenum = cpu_to_le64(offset);
1125 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
1127 return ((u64)high_crc << 31) ^ (u64)low_crc;
1130 static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
1131 struct btrfs_extent_data_ref *ref)
1133 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
1134 btrfs_extent_data_ref_objectid(leaf, ref),
1135 btrfs_extent_data_ref_offset(leaf, ref));
1138 static int match_extent_data_ref(struct extent_buffer *leaf,
1139 struct btrfs_extent_data_ref *ref,
1140 u64 root_objectid, u64 owner, u64 offset)
1142 if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
1143 btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
1144 btrfs_extent_data_ref_offset(leaf, ref) != offset)
1149 static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
1150 struct btrfs_path *path,
1151 u64 bytenr, u64 parent,
1153 u64 owner, u64 offset)
1155 struct btrfs_root *root = trans->fs_info->extent_root;
1156 struct btrfs_key key;
1157 struct btrfs_extent_data_ref *ref;
1158 struct extent_buffer *leaf;
1164 key.objectid = bytenr;
1166 key.type = BTRFS_SHARED_DATA_REF_KEY;
1167 key.offset = parent;
1169 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1170 key.offset = hash_extent_data_ref(root_objectid,
1175 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1187 leaf = path->nodes[0];
1188 nritems = btrfs_header_nritems(leaf);
1190 if (path->slots[0] >= nritems) {
1191 ret = btrfs_next_leaf(root, path);
1197 leaf = path->nodes[0];
1198 nritems = btrfs_header_nritems(leaf);
1202 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1203 if (key.objectid != bytenr ||
1204 key.type != BTRFS_EXTENT_DATA_REF_KEY)
1207 ref = btrfs_item_ptr(leaf, path->slots[0],
1208 struct btrfs_extent_data_ref);
1210 if (match_extent_data_ref(leaf, ref, root_objectid,
1213 btrfs_release_path(path);
1225 static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
1226 struct btrfs_path *path,
1227 u64 bytenr, u64 parent,
1228 u64 root_objectid, u64 owner,
1229 u64 offset, int refs_to_add)
1231 struct btrfs_root *root = trans->fs_info->extent_root;
1232 struct btrfs_key key;
1233 struct extent_buffer *leaf;
1238 key.objectid = bytenr;
1240 key.type = BTRFS_SHARED_DATA_REF_KEY;
1241 key.offset = parent;
1242 size = sizeof(struct btrfs_shared_data_ref);
1244 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1245 key.offset = hash_extent_data_ref(root_objectid,
1247 size = sizeof(struct btrfs_extent_data_ref);
1250 ret = btrfs_insert_empty_item(trans, root, path, &key, size);
1251 if (ret && ret != -EEXIST)
1254 leaf = path->nodes[0];
1256 struct btrfs_shared_data_ref *ref;
1257 ref = btrfs_item_ptr(leaf, path->slots[0],
1258 struct btrfs_shared_data_ref);
1260 btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
1262 num_refs = btrfs_shared_data_ref_count(leaf, ref);
1263 num_refs += refs_to_add;
1264 btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
1267 struct btrfs_extent_data_ref *ref;
1268 while (ret == -EEXIST) {
1269 ref = btrfs_item_ptr(leaf, path->slots[0],
1270 struct btrfs_extent_data_ref);
1271 if (match_extent_data_ref(leaf, ref, root_objectid,
1274 btrfs_release_path(path);
1276 ret = btrfs_insert_empty_item(trans, root, path, &key,
1278 if (ret && ret != -EEXIST)
1281 leaf = path->nodes[0];
1283 ref = btrfs_item_ptr(leaf, path->slots[0],
1284 struct btrfs_extent_data_ref);
1286 btrfs_set_extent_data_ref_root(leaf, ref,
1288 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
1289 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
1290 btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
1292 num_refs = btrfs_extent_data_ref_count(leaf, ref);
1293 num_refs += refs_to_add;
1294 btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
1297 btrfs_mark_buffer_dirty(leaf);
1300 btrfs_release_path(path);
1304 static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
1305 struct btrfs_path *path,
1306 int refs_to_drop, int *last_ref)
1308 struct btrfs_key key;
1309 struct btrfs_extent_data_ref *ref1 = NULL;
1310 struct btrfs_shared_data_ref *ref2 = NULL;
1311 struct extent_buffer *leaf;
1315 leaf = path->nodes[0];
1316 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1318 if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1319 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1320 struct btrfs_extent_data_ref);
1321 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1322 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1323 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1324 struct btrfs_shared_data_ref);
1325 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1326 } else if (unlikely(key.type == BTRFS_EXTENT_REF_V0_KEY)) {
1327 btrfs_print_v0_err(trans->fs_info);
1328 btrfs_abort_transaction(trans, -EINVAL);
1334 BUG_ON(num_refs < refs_to_drop);
1335 num_refs -= refs_to_drop;
1337 if (num_refs == 0) {
1338 ret = btrfs_del_item(trans, trans->fs_info->extent_root, path);
1341 if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
1342 btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
1343 else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
1344 btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
1345 btrfs_mark_buffer_dirty(leaf);
1350 static noinline u32 extent_data_ref_count(struct btrfs_path *path,
1351 struct btrfs_extent_inline_ref *iref)
1353 struct btrfs_key key;
1354 struct extent_buffer *leaf;
1355 struct btrfs_extent_data_ref *ref1;
1356 struct btrfs_shared_data_ref *ref2;
1360 leaf = path->nodes[0];
1361 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1363 BUG_ON(key.type == BTRFS_EXTENT_REF_V0_KEY);
1366 * If type is invalid, we should have bailed out earlier than
1369 type = btrfs_get_extent_inline_ref_type(leaf, iref, BTRFS_REF_TYPE_DATA);
1370 ASSERT(type != BTRFS_REF_TYPE_INVALID);
1371 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1372 ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
1373 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1375 ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
1376 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1378 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1379 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1380 struct btrfs_extent_data_ref);
1381 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1382 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1383 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1384 struct btrfs_shared_data_ref);
1385 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1392 static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
1393 struct btrfs_path *path,
1394 u64 bytenr, u64 parent,
1397 struct btrfs_root *root = trans->fs_info->extent_root;
1398 struct btrfs_key key;
1401 key.objectid = bytenr;
1403 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1404 key.offset = parent;
1406 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1407 key.offset = root_objectid;
1410 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1416 static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
1417 struct btrfs_path *path,
1418 u64 bytenr, u64 parent,
1421 struct btrfs_key key;
1424 key.objectid = bytenr;
1426 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1427 key.offset = parent;
1429 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1430 key.offset = root_objectid;
1433 ret = btrfs_insert_empty_item(trans, trans->fs_info->extent_root,
1435 btrfs_release_path(path);
1439 static inline int extent_ref_type(u64 parent, u64 owner)
1442 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1444 type = BTRFS_SHARED_BLOCK_REF_KEY;
1446 type = BTRFS_TREE_BLOCK_REF_KEY;
1449 type = BTRFS_SHARED_DATA_REF_KEY;
1451 type = BTRFS_EXTENT_DATA_REF_KEY;
1456 static int find_next_key(struct btrfs_path *path, int level,
1457 struct btrfs_key *key)
1460 for (; level < BTRFS_MAX_LEVEL; level++) {
1461 if (!path->nodes[level])
1463 if (path->slots[level] + 1 >=
1464 btrfs_header_nritems(path->nodes[level]))
1467 btrfs_item_key_to_cpu(path->nodes[level], key,
1468 path->slots[level] + 1);
1470 btrfs_node_key_to_cpu(path->nodes[level], key,
1471 path->slots[level] + 1);
1478 * look for inline back ref. if back ref is found, *ref_ret is set
1479 * to the address of inline back ref, and 0 is returned.
1481 * if back ref isn't found, *ref_ret is set to the address where it
1482 * should be inserted, and -ENOENT is returned.
1484 * if insert is true and there are too many inline back refs, the path
1485 * points to the extent item, and -EAGAIN is returned.
1487 * NOTE: inline back refs are ordered in the same way that back ref
1488 * items in the tree are ordered.
1490 static noinline_for_stack
1491 int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
1492 struct btrfs_path *path,
1493 struct btrfs_extent_inline_ref **ref_ret,
1494 u64 bytenr, u64 num_bytes,
1495 u64 parent, u64 root_objectid,
1496 u64 owner, u64 offset, int insert)
1498 struct btrfs_fs_info *fs_info = trans->fs_info;
1499 struct btrfs_root *root = fs_info->extent_root;
1500 struct btrfs_key key;
1501 struct extent_buffer *leaf;
1502 struct btrfs_extent_item *ei;
1503 struct btrfs_extent_inline_ref *iref;
1513 bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
1516 key.objectid = bytenr;
1517 key.type = BTRFS_EXTENT_ITEM_KEY;
1518 key.offset = num_bytes;
1520 want = extent_ref_type(parent, owner);
1522 extra_size = btrfs_extent_inline_ref_size(want);
1523 path->keep_locks = 1;
1528 * Owner is our level, so we can just add one to get the level for the
1529 * block we are interested in.
1531 if (skinny_metadata && owner < BTRFS_FIRST_FREE_OBJECTID) {
1532 key.type = BTRFS_METADATA_ITEM_KEY;
1537 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
1544 * We may be a newly converted file system which still has the old fat
1545 * extent entries for metadata, so try and see if we have one of those.
1547 if (ret > 0 && skinny_metadata) {
1548 skinny_metadata = false;
1549 if (path->slots[0]) {
1551 btrfs_item_key_to_cpu(path->nodes[0], &key,
1553 if (key.objectid == bytenr &&
1554 key.type == BTRFS_EXTENT_ITEM_KEY &&
1555 key.offset == num_bytes)
1559 key.objectid = bytenr;
1560 key.type = BTRFS_EXTENT_ITEM_KEY;
1561 key.offset = num_bytes;
1562 btrfs_release_path(path);
1567 if (ret && !insert) {
1570 } else if (WARN_ON(ret)) {
1575 leaf = path->nodes[0];
1576 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1577 if (unlikely(item_size < sizeof(*ei))) {
1579 btrfs_print_v0_err(fs_info);
1580 btrfs_abort_transaction(trans, err);
1584 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1585 flags = btrfs_extent_flags(leaf, ei);
1587 ptr = (unsigned long)(ei + 1);
1588 end = (unsigned long)ei + item_size;
1590 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK && !skinny_metadata) {
1591 ptr += sizeof(struct btrfs_tree_block_info);
1595 if (owner >= BTRFS_FIRST_FREE_OBJECTID)
1596 needed = BTRFS_REF_TYPE_DATA;
1598 needed = BTRFS_REF_TYPE_BLOCK;
1606 iref = (struct btrfs_extent_inline_ref *)ptr;
1607 type = btrfs_get_extent_inline_ref_type(leaf, iref, needed);
1608 if (type == BTRFS_REF_TYPE_INVALID) {
1616 ptr += btrfs_extent_inline_ref_size(type);
1620 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1621 struct btrfs_extent_data_ref *dref;
1622 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1623 if (match_extent_data_ref(leaf, dref, root_objectid,
1628 if (hash_extent_data_ref_item(leaf, dref) <
1629 hash_extent_data_ref(root_objectid, owner, offset))
1633 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1635 if (parent == ref_offset) {
1639 if (ref_offset < parent)
1642 if (root_objectid == ref_offset) {
1646 if (ref_offset < root_objectid)
1650 ptr += btrfs_extent_inline_ref_size(type);
1652 if (err == -ENOENT && insert) {
1653 if (item_size + extra_size >=
1654 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
1659 * To add new inline back ref, we have to make sure
1660 * there is no corresponding back ref item.
1661 * For simplicity, we just do not add new inline back
1662 * ref if there is any kind of item for this block
1664 if (find_next_key(path, 0, &key) == 0 &&
1665 key.objectid == bytenr &&
1666 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
1671 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
1674 path->keep_locks = 0;
1675 btrfs_unlock_up_safe(path, 1);
1681 * helper to add new inline back ref
1683 static noinline_for_stack
1684 void setup_inline_extent_backref(struct btrfs_fs_info *fs_info,
1685 struct btrfs_path *path,
1686 struct btrfs_extent_inline_ref *iref,
1687 u64 parent, u64 root_objectid,
1688 u64 owner, u64 offset, int refs_to_add,
1689 struct btrfs_delayed_extent_op *extent_op)
1691 struct extent_buffer *leaf;
1692 struct btrfs_extent_item *ei;
1695 unsigned long item_offset;
1700 leaf = path->nodes[0];
1701 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1702 item_offset = (unsigned long)iref - (unsigned long)ei;
1704 type = extent_ref_type(parent, owner);
1705 size = btrfs_extent_inline_ref_size(type);
1707 btrfs_extend_item(fs_info, path, size);
1709 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1710 refs = btrfs_extent_refs(leaf, ei);
1711 refs += refs_to_add;
1712 btrfs_set_extent_refs(leaf, ei, refs);
1714 __run_delayed_extent_op(extent_op, leaf, ei);
1716 ptr = (unsigned long)ei + item_offset;
1717 end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
1718 if (ptr < end - size)
1719 memmove_extent_buffer(leaf, ptr + size, ptr,
1722 iref = (struct btrfs_extent_inline_ref *)ptr;
1723 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1724 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1725 struct btrfs_extent_data_ref *dref;
1726 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1727 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1728 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1729 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1730 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1731 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1732 struct btrfs_shared_data_ref *sref;
1733 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1734 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1735 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1736 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1737 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1739 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1741 btrfs_mark_buffer_dirty(leaf);
1744 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1745 struct btrfs_path *path,
1746 struct btrfs_extent_inline_ref **ref_ret,
1747 u64 bytenr, u64 num_bytes, u64 parent,
1748 u64 root_objectid, u64 owner, u64 offset)
1752 ret = lookup_inline_extent_backref(trans, path, ref_ret, bytenr,
1753 num_bytes, parent, root_objectid,
1758 btrfs_release_path(path);
1761 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1762 ret = lookup_tree_block_ref(trans, path, bytenr, parent,
1765 ret = lookup_extent_data_ref(trans, path, bytenr, parent,
1766 root_objectid, owner, offset);
1772 * helper to update/remove inline back ref
1774 static noinline_for_stack
1775 void update_inline_extent_backref(struct btrfs_path *path,
1776 struct btrfs_extent_inline_ref *iref,
1778 struct btrfs_delayed_extent_op *extent_op,
1781 struct extent_buffer *leaf = path->nodes[0];
1782 struct btrfs_fs_info *fs_info = leaf->fs_info;
1783 struct btrfs_extent_item *ei;
1784 struct btrfs_extent_data_ref *dref = NULL;
1785 struct btrfs_shared_data_ref *sref = NULL;
1793 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1794 refs = btrfs_extent_refs(leaf, ei);
1795 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1796 refs += refs_to_mod;
1797 btrfs_set_extent_refs(leaf, ei, refs);
1799 __run_delayed_extent_op(extent_op, leaf, ei);
1802 * If type is invalid, we should have bailed out after
1803 * lookup_inline_extent_backref().
1805 type = btrfs_get_extent_inline_ref_type(leaf, iref, BTRFS_REF_TYPE_ANY);
1806 ASSERT(type != BTRFS_REF_TYPE_INVALID);
1808 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1809 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1810 refs = btrfs_extent_data_ref_count(leaf, dref);
1811 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1812 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1813 refs = btrfs_shared_data_ref_count(leaf, sref);
1816 BUG_ON(refs_to_mod != -1);
1819 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1820 refs += refs_to_mod;
1823 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1824 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1826 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1829 size = btrfs_extent_inline_ref_size(type);
1830 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1831 ptr = (unsigned long)iref;
1832 end = (unsigned long)ei + item_size;
1833 if (ptr + size < end)
1834 memmove_extent_buffer(leaf, ptr, ptr + size,
1837 btrfs_truncate_item(fs_info, path, item_size, 1);
1839 btrfs_mark_buffer_dirty(leaf);
1842 static noinline_for_stack
1843 int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1844 struct btrfs_path *path,
1845 u64 bytenr, u64 num_bytes, u64 parent,
1846 u64 root_objectid, u64 owner,
1847 u64 offset, int refs_to_add,
1848 struct btrfs_delayed_extent_op *extent_op)
1850 struct btrfs_extent_inline_ref *iref;
1853 ret = lookup_inline_extent_backref(trans, path, &iref, bytenr,
1854 num_bytes, parent, root_objectid,
1857 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
1858 update_inline_extent_backref(path, iref, refs_to_add,
1860 } else if (ret == -ENOENT) {
1861 setup_inline_extent_backref(trans->fs_info, path, iref, parent,
1862 root_objectid, owner, offset,
1863 refs_to_add, extent_op);
1869 static int insert_extent_backref(struct btrfs_trans_handle *trans,
1870 struct btrfs_path *path,
1871 u64 bytenr, u64 parent, u64 root_objectid,
1872 u64 owner, u64 offset, int refs_to_add)
1875 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1876 BUG_ON(refs_to_add != 1);
1877 ret = insert_tree_block_ref(trans, path, bytenr, parent,
1880 ret = insert_extent_data_ref(trans, path, bytenr, parent,
1881 root_objectid, owner, offset,
1887 static int remove_extent_backref(struct btrfs_trans_handle *trans,
1888 struct btrfs_path *path,
1889 struct btrfs_extent_inline_ref *iref,
1890 int refs_to_drop, int is_data, int *last_ref)
1894 BUG_ON(!is_data && refs_to_drop != 1);
1896 update_inline_extent_backref(path, iref, -refs_to_drop, NULL,
1898 } else if (is_data) {
1899 ret = remove_extent_data_ref(trans, path, refs_to_drop,
1903 ret = btrfs_del_item(trans, trans->fs_info->extent_root, path);
1908 #define in_range(b, first, len) ((b) >= (first) && (b) < (first) + (len))
1909 static int btrfs_issue_discard(struct block_device *bdev, u64 start, u64 len,
1910 u64 *discarded_bytes)
1913 u64 bytes_left, end;
1914 u64 aligned_start = ALIGN(start, 1 << 9);
1916 if (WARN_ON(start != aligned_start)) {
1917 len -= aligned_start - start;
1918 len = round_down(len, 1 << 9);
1919 start = aligned_start;
1922 *discarded_bytes = 0;
1930 /* Skip any superblocks on this device. */
1931 for (j = 0; j < BTRFS_SUPER_MIRROR_MAX; j++) {
1932 u64 sb_start = btrfs_sb_offset(j);
1933 u64 sb_end = sb_start + BTRFS_SUPER_INFO_SIZE;
1934 u64 size = sb_start - start;
1936 if (!in_range(sb_start, start, bytes_left) &&
1937 !in_range(sb_end, start, bytes_left) &&
1938 !in_range(start, sb_start, BTRFS_SUPER_INFO_SIZE))
1942 * Superblock spans beginning of range. Adjust start and
1945 if (sb_start <= start) {
1946 start += sb_end - start;
1951 bytes_left = end - start;
1956 ret = blkdev_issue_discard(bdev, start >> 9, size >> 9,
1959 *discarded_bytes += size;
1960 else if (ret != -EOPNOTSUPP)
1969 bytes_left = end - start;
1973 ret = blkdev_issue_discard(bdev, start >> 9, bytes_left >> 9,
1976 *discarded_bytes += bytes_left;
1981 int btrfs_discard_extent(struct btrfs_fs_info *fs_info, u64 bytenr,
1982 u64 num_bytes, u64 *actual_bytes)
1985 u64 discarded_bytes = 0;
1986 struct btrfs_bio *bbio = NULL;
1990 * Avoid races with device replace and make sure our bbio has devices
1991 * associated to its stripes that don't go away while we are discarding.
1993 btrfs_bio_counter_inc_blocked(fs_info);
1994 /* Tell the block device(s) that the sectors can be discarded */
1995 ret = btrfs_map_block(fs_info, BTRFS_MAP_DISCARD, bytenr, &num_bytes,
1997 /* Error condition is -ENOMEM */
1999 struct btrfs_bio_stripe *stripe = bbio->stripes;
2003 for (i = 0; i < bbio->num_stripes; i++, stripe++) {
2005 struct request_queue *req_q;
2007 if (!stripe->dev->bdev) {
2008 ASSERT(btrfs_test_opt(fs_info, DEGRADED));
2011 req_q = bdev_get_queue(stripe->dev->bdev);
2012 if (!blk_queue_discard(req_q))
2015 ret = btrfs_issue_discard(stripe->dev->bdev,
2020 discarded_bytes += bytes;
2021 else if (ret != -EOPNOTSUPP)
2022 break; /* Logic errors or -ENOMEM, or -EIO but I don't know how that could happen JDM */
2025 * Just in case we get back EOPNOTSUPP for some reason,
2026 * just ignore the return value so we don't screw up
2027 * people calling discard_extent.
2031 btrfs_put_bbio(bbio);
2033 btrfs_bio_counter_dec(fs_info);
2036 *actual_bytes = discarded_bytes;
2039 if (ret == -EOPNOTSUPP)
2044 /* Can return -ENOMEM */
2045 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
2046 struct btrfs_root *root,
2047 u64 bytenr, u64 num_bytes, u64 parent,
2048 u64 root_objectid, u64 owner, u64 offset)
2050 struct btrfs_fs_info *fs_info = root->fs_info;
2051 int old_ref_mod, new_ref_mod;
2054 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID &&
2055 root_objectid == BTRFS_TREE_LOG_OBJECTID);
2057 btrfs_ref_tree_mod(root, bytenr, num_bytes, parent, root_objectid,
2058 owner, offset, BTRFS_ADD_DELAYED_REF);
2060 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
2061 ret = btrfs_add_delayed_tree_ref(trans, bytenr,
2063 root_objectid, (int)owner,
2064 BTRFS_ADD_DELAYED_REF, NULL,
2065 &old_ref_mod, &new_ref_mod);
2067 ret = btrfs_add_delayed_data_ref(trans, bytenr,
2069 root_objectid, owner, offset,
2070 0, BTRFS_ADD_DELAYED_REF,
2071 &old_ref_mod, &new_ref_mod);
2074 if (ret == 0 && old_ref_mod < 0 && new_ref_mod >= 0) {
2075 bool metadata = owner < BTRFS_FIRST_FREE_OBJECTID;
2077 add_pinned_bytes(fs_info, -num_bytes, metadata, root_objectid);
2084 * __btrfs_inc_extent_ref - insert backreference for a given extent
2086 * @trans: Handle of transaction
2088 * @node: The delayed ref node used to get the bytenr/length for
2089 * extent whose references are incremented.
2091 * @parent: If this is a shared extent (BTRFS_SHARED_DATA_REF_KEY/
2092 * BTRFS_SHARED_BLOCK_REF_KEY) then it holds the logical
2093 * bytenr of the parent block. Since new extents are always
2094 * created with indirect references, this will only be the case
2095 * when relocating a shared extent. In that case, root_objectid
2096 * will be BTRFS_TREE_RELOC_OBJECTID. Otheriwse, parent must
2099 * @root_objectid: The id of the root where this modification has originated,
2100 * this can be either one of the well-known metadata trees or
2101 * the subvolume id which references this extent.
2103 * @owner: For data extents it is the inode number of the owning file.
2104 * For metadata extents this parameter holds the level in the
2105 * tree of the extent.
2107 * @offset: For metadata extents the offset is ignored and is currently
2108 * always passed as 0. For data extents it is the fileoffset
2109 * this extent belongs to.
2111 * @refs_to_add Number of references to add
2113 * @extent_op Pointer to a structure, holding information necessary when
2114 * updating a tree block's flags
2117 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
2118 struct btrfs_delayed_ref_node *node,
2119 u64 parent, u64 root_objectid,
2120 u64 owner, u64 offset, int refs_to_add,
2121 struct btrfs_delayed_extent_op *extent_op)
2123 struct btrfs_path *path;
2124 struct extent_buffer *leaf;
2125 struct btrfs_extent_item *item;
2126 struct btrfs_key key;
2127 u64 bytenr = node->bytenr;
2128 u64 num_bytes = node->num_bytes;
2132 path = btrfs_alloc_path();
2136 path->reada = READA_FORWARD;
2137 path->leave_spinning = 1;
2138 /* this will setup the path even if it fails to insert the back ref */
2139 ret = insert_inline_extent_backref(trans, path, bytenr, num_bytes,
2140 parent, root_objectid, owner,
2141 offset, refs_to_add, extent_op);
2142 if ((ret < 0 && ret != -EAGAIN) || !ret)
2146 * Ok we had -EAGAIN which means we didn't have space to insert and
2147 * inline extent ref, so just update the reference count and add a
2150 leaf = path->nodes[0];
2151 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2152 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2153 refs = btrfs_extent_refs(leaf, item);
2154 btrfs_set_extent_refs(leaf, item, refs + refs_to_add);
2156 __run_delayed_extent_op(extent_op, leaf, item);
2158 btrfs_mark_buffer_dirty(leaf);
2159 btrfs_release_path(path);
2161 path->reada = READA_FORWARD;
2162 path->leave_spinning = 1;
2163 /* now insert the actual backref */
2164 ret = insert_extent_backref(trans, path, bytenr, parent, root_objectid,
2165 owner, offset, refs_to_add);
2167 btrfs_abort_transaction(trans, ret);
2169 btrfs_free_path(path);
2173 static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
2174 struct btrfs_delayed_ref_node *node,
2175 struct btrfs_delayed_extent_op *extent_op,
2176 int insert_reserved)
2179 struct btrfs_delayed_data_ref *ref;
2180 struct btrfs_key ins;
2185 ins.objectid = node->bytenr;
2186 ins.offset = node->num_bytes;
2187 ins.type = BTRFS_EXTENT_ITEM_KEY;
2189 ref = btrfs_delayed_node_to_data_ref(node);
2190 trace_run_delayed_data_ref(trans->fs_info, node, ref, node->action);
2192 if (node->type == BTRFS_SHARED_DATA_REF_KEY)
2193 parent = ref->parent;
2194 ref_root = ref->root;
2196 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
2198 flags |= extent_op->flags_to_set;
2199 ret = alloc_reserved_file_extent(trans, parent, ref_root,
2200 flags, ref->objectid,
2203 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
2204 ret = __btrfs_inc_extent_ref(trans, node, parent, ref_root,
2205 ref->objectid, ref->offset,
2206 node->ref_mod, extent_op);
2207 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
2208 ret = __btrfs_free_extent(trans, node, parent,
2209 ref_root, ref->objectid,
2210 ref->offset, node->ref_mod,
2218 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
2219 struct extent_buffer *leaf,
2220 struct btrfs_extent_item *ei)
2222 u64 flags = btrfs_extent_flags(leaf, ei);
2223 if (extent_op->update_flags) {
2224 flags |= extent_op->flags_to_set;
2225 btrfs_set_extent_flags(leaf, ei, flags);
2228 if (extent_op->update_key) {
2229 struct btrfs_tree_block_info *bi;
2230 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK));
2231 bi = (struct btrfs_tree_block_info *)(ei + 1);
2232 btrfs_set_tree_block_key(leaf, bi, &extent_op->key);
2236 static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
2237 struct btrfs_delayed_ref_head *head,
2238 struct btrfs_delayed_extent_op *extent_op)
2240 struct btrfs_fs_info *fs_info = trans->fs_info;
2241 struct btrfs_key key;
2242 struct btrfs_path *path;
2243 struct btrfs_extent_item *ei;
2244 struct extent_buffer *leaf;
2248 int metadata = !extent_op->is_data;
2253 if (metadata && !btrfs_fs_incompat(fs_info, SKINNY_METADATA))
2256 path = btrfs_alloc_path();
2260 key.objectid = head->bytenr;
2263 key.type = BTRFS_METADATA_ITEM_KEY;
2264 key.offset = extent_op->level;
2266 key.type = BTRFS_EXTENT_ITEM_KEY;
2267 key.offset = head->num_bytes;
2271 path->reada = READA_FORWARD;
2272 path->leave_spinning = 1;
2273 ret = btrfs_search_slot(trans, fs_info->extent_root, &key, path, 0, 1);
2280 if (path->slots[0] > 0) {
2282 btrfs_item_key_to_cpu(path->nodes[0], &key,
2284 if (key.objectid == head->bytenr &&
2285 key.type == BTRFS_EXTENT_ITEM_KEY &&
2286 key.offset == head->num_bytes)
2290 btrfs_release_path(path);
2293 key.objectid = head->bytenr;
2294 key.offset = head->num_bytes;
2295 key.type = BTRFS_EXTENT_ITEM_KEY;
2304 leaf = path->nodes[0];
2305 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2307 if (unlikely(item_size < sizeof(*ei))) {
2309 btrfs_print_v0_err(fs_info);
2310 btrfs_abort_transaction(trans, err);
2314 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2315 __run_delayed_extent_op(extent_op, leaf, ei);
2317 btrfs_mark_buffer_dirty(leaf);
2319 btrfs_free_path(path);
2323 static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
2324 struct btrfs_delayed_ref_node *node,
2325 struct btrfs_delayed_extent_op *extent_op,
2326 int insert_reserved)
2329 struct btrfs_delayed_tree_ref *ref;
2333 ref = btrfs_delayed_node_to_tree_ref(node);
2334 trace_run_delayed_tree_ref(trans->fs_info, node, ref, node->action);
2336 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2337 parent = ref->parent;
2338 ref_root = ref->root;
2340 if (node->ref_mod != 1) {
2341 btrfs_err(trans->fs_info,
2342 "btree block(%llu) has %d references rather than 1: action %d ref_root %llu parent %llu",
2343 node->bytenr, node->ref_mod, node->action, ref_root,
2347 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
2348 BUG_ON(!extent_op || !extent_op->update_flags);
2349 ret = alloc_reserved_tree_block(trans, node, extent_op);
2350 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
2351 ret = __btrfs_inc_extent_ref(trans, node, parent, ref_root,
2352 ref->level, 0, 1, extent_op);
2353 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
2354 ret = __btrfs_free_extent(trans, node, parent, ref_root,
2355 ref->level, 0, 1, extent_op);
2362 /* helper function to actually process a single delayed ref entry */
2363 static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
2364 struct btrfs_delayed_ref_node *node,
2365 struct btrfs_delayed_extent_op *extent_op,
2366 int insert_reserved)
2370 if (trans->aborted) {
2371 if (insert_reserved)
2372 btrfs_pin_extent(trans->fs_info, node->bytenr,
2373 node->num_bytes, 1);
2377 if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
2378 node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2379 ret = run_delayed_tree_ref(trans, node, extent_op,
2381 else if (node->type == BTRFS_EXTENT_DATA_REF_KEY ||
2382 node->type == BTRFS_SHARED_DATA_REF_KEY)
2383 ret = run_delayed_data_ref(trans, node, extent_op,
2387 if (ret && insert_reserved)
2388 btrfs_pin_extent(trans->fs_info, node->bytenr,
2389 node->num_bytes, 1);
2393 static inline struct btrfs_delayed_ref_node *
2394 select_delayed_ref(struct btrfs_delayed_ref_head *head)
2396 struct btrfs_delayed_ref_node *ref;
2398 if (RB_EMPTY_ROOT(&head->ref_tree.rb_root))
2402 * Select a delayed ref of type BTRFS_ADD_DELAYED_REF first.
2403 * This is to prevent a ref count from going down to zero, which deletes
2404 * the extent item from the extent tree, when there still are references
2405 * to add, which would fail because they would not find the extent item.
2407 if (!list_empty(&head->ref_add_list))
2408 return list_first_entry(&head->ref_add_list,
2409 struct btrfs_delayed_ref_node, add_list);
2411 ref = rb_entry(rb_first_cached(&head->ref_tree),
2412 struct btrfs_delayed_ref_node, ref_node);
2413 ASSERT(list_empty(&ref->add_list));
2417 static void unselect_delayed_ref_head(struct btrfs_delayed_ref_root *delayed_refs,
2418 struct btrfs_delayed_ref_head *head)
2420 spin_lock(&delayed_refs->lock);
2421 head->processing = 0;
2422 delayed_refs->num_heads_ready++;
2423 spin_unlock(&delayed_refs->lock);
2424 btrfs_delayed_ref_unlock(head);
2427 static struct btrfs_delayed_extent_op *cleanup_extent_op(
2428 struct btrfs_delayed_ref_head *head)
2430 struct btrfs_delayed_extent_op *extent_op = head->extent_op;
2435 if (head->must_insert_reserved) {
2436 head->extent_op = NULL;
2437 btrfs_free_delayed_extent_op(extent_op);
2443 static int run_and_cleanup_extent_op(struct btrfs_trans_handle *trans,
2444 struct btrfs_delayed_ref_head *head)
2446 struct btrfs_delayed_extent_op *extent_op;
2449 extent_op = cleanup_extent_op(head);
2452 head->extent_op = NULL;
2453 spin_unlock(&head->lock);
2454 ret = run_delayed_extent_op(trans, head, extent_op);
2455 btrfs_free_delayed_extent_op(extent_op);
2456 return ret ? ret : 1;
2459 void btrfs_cleanup_ref_head_accounting(struct btrfs_fs_info *fs_info,
2460 struct btrfs_delayed_ref_root *delayed_refs,
2461 struct btrfs_delayed_ref_head *head)
2463 int nr_items = 1; /* Dropping this ref head update. */
2465 if (head->total_ref_mod < 0) {
2466 struct btrfs_space_info *space_info;
2470 flags = BTRFS_BLOCK_GROUP_DATA;
2471 else if (head->is_system)
2472 flags = BTRFS_BLOCK_GROUP_SYSTEM;
2474 flags = BTRFS_BLOCK_GROUP_METADATA;
2475 space_info = __find_space_info(fs_info, flags);
2477 percpu_counter_add_batch(&space_info->total_bytes_pinned,
2479 BTRFS_TOTAL_BYTES_PINNED_BATCH);
2482 * We had csum deletions accounted for in our delayed refs rsv,
2483 * we need to drop the csum leaves for this update from our
2486 if (head->is_data) {
2487 spin_lock(&delayed_refs->lock);
2488 delayed_refs->pending_csums -= head->num_bytes;
2489 spin_unlock(&delayed_refs->lock);
2490 nr_items += btrfs_csum_bytes_to_leaves(fs_info,
2495 btrfs_delayed_refs_rsv_release(fs_info, nr_items);
2498 static int cleanup_ref_head(struct btrfs_trans_handle *trans,
2499 struct btrfs_delayed_ref_head *head)
2502 struct btrfs_fs_info *fs_info = trans->fs_info;
2503 struct btrfs_delayed_ref_root *delayed_refs;
2506 delayed_refs = &trans->transaction->delayed_refs;
2508 ret = run_and_cleanup_extent_op(trans, head);
2510 unselect_delayed_ref_head(delayed_refs, head);
2511 btrfs_debug(fs_info, "run_delayed_extent_op returned %d", ret);
2518 * Need to drop our head ref lock and re-acquire the delayed ref lock
2519 * and then re-check to make sure nobody got added.
2521 spin_unlock(&head->lock);
2522 spin_lock(&delayed_refs->lock);
2523 spin_lock(&head->lock);
2524 if (!RB_EMPTY_ROOT(&head->ref_tree.rb_root) || head->extent_op) {
2525 spin_unlock(&head->lock);
2526 spin_unlock(&delayed_refs->lock);
2529 btrfs_delete_ref_head(delayed_refs, head);
2530 spin_unlock(&head->lock);
2531 spin_unlock(&delayed_refs->lock);
2533 if (head->must_insert_reserved) {
2534 btrfs_pin_extent(fs_info, head->bytenr,
2535 head->num_bytes, 1);
2536 if (head->is_data) {
2537 ret = btrfs_del_csums(trans, fs_info, head->bytenr,
2542 btrfs_cleanup_ref_head_accounting(fs_info, delayed_refs, head);
2544 trace_run_delayed_ref_head(fs_info, head, 0);
2545 btrfs_delayed_ref_unlock(head);
2546 btrfs_put_delayed_ref_head(head);
2550 static struct btrfs_delayed_ref_head *btrfs_obtain_ref_head(
2551 struct btrfs_trans_handle *trans)
2553 struct btrfs_delayed_ref_root *delayed_refs =
2554 &trans->transaction->delayed_refs;
2555 struct btrfs_delayed_ref_head *head = NULL;
2558 spin_lock(&delayed_refs->lock);
2559 head = btrfs_select_ref_head(delayed_refs);
2561 spin_unlock(&delayed_refs->lock);
2566 * Grab the lock that says we are going to process all the refs for
2569 ret = btrfs_delayed_ref_lock(delayed_refs, head);
2570 spin_unlock(&delayed_refs->lock);
2573 * We may have dropped the spin lock to get the head mutex lock, and
2574 * that might have given someone else time to free the head. If that's
2575 * true, it has been removed from our list and we can move on.
2578 head = ERR_PTR(-EAGAIN);
2583 static int btrfs_run_delayed_refs_for_head(struct btrfs_trans_handle *trans,
2584 struct btrfs_delayed_ref_head *locked_ref,
2585 unsigned long *run_refs)
2587 struct btrfs_fs_info *fs_info = trans->fs_info;
2588 struct btrfs_delayed_ref_root *delayed_refs;
2589 struct btrfs_delayed_extent_op *extent_op;
2590 struct btrfs_delayed_ref_node *ref;
2591 int must_insert_reserved = 0;
2594 delayed_refs = &trans->transaction->delayed_refs;
2596 lockdep_assert_held(&locked_ref->mutex);
2597 lockdep_assert_held(&locked_ref->lock);
2599 while ((ref = select_delayed_ref(locked_ref))) {
2601 btrfs_check_delayed_seq(fs_info, ref->seq)) {
2602 spin_unlock(&locked_ref->lock);
2603 unselect_delayed_ref_head(delayed_refs, locked_ref);
2609 rb_erase_cached(&ref->ref_node, &locked_ref->ref_tree);
2610 RB_CLEAR_NODE(&ref->ref_node);
2611 if (!list_empty(&ref->add_list))
2612 list_del(&ref->add_list);
2614 * When we play the delayed ref, also correct the ref_mod on
2617 switch (ref->action) {
2618 case BTRFS_ADD_DELAYED_REF:
2619 case BTRFS_ADD_DELAYED_EXTENT:
2620 locked_ref->ref_mod -= ref->ref_mod;
2622 case BTRFS_DROP_DELAYED_REF:
2623 locked_ref->ref_mod += ref->ref_mod;
2628 atomic_dec(&delayed_refs->num_entries);
2631 * Record the must_insert_reserved flag before we drop the
2634 must_insert_reserved = locked_ref->must_insert_reserved;
2635 locked_ref->must_insert_reserved = 0;
2637 extent_op = locked_ref->extent_op;
2638 locked_ref->extent_op = NULL;
2639 spin_unlock(&locked_ref->lock);
2641 ret = run_one_delayed_ref(trans, ref, extent_op,
2642 must_insert_reserved);
2644 btrfs_free_delayed_extent_op(extent_op);
2646 unselect_delayed_ref_head(delayed_refs, locked_ref);
2647 btrfs_put_delayed_ref(ref);
2648 btrfs_debug(fs_info, "run_one_delayed_ref returned %d",
2653 btrfs_put_delayed_ref(ref);
2656 spin_lock(&locked_ref->lock);
2657 btrfs_merge_delayed_refs(trans, delayed_refs, locked_ref);
2664 * Returns 0 on success or if called with an already aborted transaction.
2665 * Returns -ENOMEM or -EIO on failure and will abort the transaction.
2667 static noinline int __btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2670 struct btrfs_fs_info *fs_info = trans->fs_info;
2671 struct btrfs_delayed_ref_root *delayed_refs;
2672 struct btrfs_delayed_ref_head *locked_ref = NULL;
2673 ktime_t start = ktime_get();
2675 unsigned long count = 0;
2676 unsigned long actual_count = 0;
2678 delayed_refs = &trans->transaction->delayed_refs;
2681 locked_ref = btrfs_obtain_ref_head(trans);
2682 if (IS_ERR_OR_NULL(locked_ref)) {
2683 if (PTR_ERR(locked_ref) == -EAGAIN) {
2692 * We need to try and merge add/drops of the same ref since we
2693 * can run into issues with relocate dropping the implicit ref
2694 * and then it being added back again before the drop can
2695 * finish. If we merged anything we need to re-loop so we can
2697 * Or we can get node references of the same type that weren't
2698 * merged when created due to bumps in the tree mod seq, and
2699 * we need to merge them to prevent adding an inline extent
2700 * backref before dropping it (triggering a BUG_ON at
2701 * insert_inline_extent_backref()).
2703 spin_lock(&locked_ref->lock);
2704 btrfs_merge_delayed_refs(trans, delayed_refs, locked_ref);
2706 ret = btrfs_run_delayed_refs_for_head(trans, locked_ref,
2708 if (ret < 0 && ret != -EAGAIN) {
2710 * Error, btrfs_run_delayed_refs_for_head already
2711 * unlocked everything so just bail out
2716 * Success, perform the usual cleanup of a processed
2719 ret = cleanup_ref_head(trans, locked_ref);
2721 /* We dropped our lock, we need to loop. */
2730 * Either success case or btrfs_run_delayed_refs_for_head
2731 * returned -EAGAIN, meaning we need to select another head
2736 } while ((nr != -1 && count < nr) || locked_ref);
2739 * We don't want to include ref heads since we can have empty ref heads
2740 * and those will drastically skew our runtime down since we just do
2741 * accounting, no actual extent tree updates.
2743 if (actual_count > 0) {
2744 u64 runtime = ktime_to_ns(ktime_sub(ktime_get(), start));
2748 * We weigh the current average higher than our current runtime
2749 * to avoid large swings in the average.
2751 spin_lock(&delayed_refs->lock);
2752 avg = fs_info->avg_delayed_ref_runtime * 3 + runtime;
2753 fs_info->avg_delayed_ref_runtime = avg >> 2; /* div by 4 */
2754 spin_unlock(&delayed_refs->lock);
2759 #ifdef SCRAMBLE_DELAYED_REFS
2761 * Normally delayed refs get processed in ascending bytenr order. This
2762 * correlates in most cases to the order added. To expose dependencies on this
2763 * order, we start to process the tree in the middle instead of the beginning
2765 static u64 find_middle(struct rb_root *root)
2767 struct rb_node *n = root->rb_node;
2768 struct btrfs_delayed_ref_node *entry;
2771 u64 first = 0, last = 0;
2775 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2776 first = entry->bytenr;
2780 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2781 last = entry->bytenr;
2786 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2787 WARN_ON(!entry->in_tree);
2789 middle = entry->bytenr;
2802 static inline u64 heads_to_leaves(struct btrfs_fs_info *fs_info, u64 heads)
2806 num_bytes = heads * (sizeof(struct btrfs_extent_item) +
2807 sizeof(struct btrfs_extent_inline_ref));
2808 if (!btrfs_fs_incompat(fs_info, SKINNY_METADATA))
2809 num_bytes += heads * sizeof(struct btrfs_tree_block_info);
2812 * We don't ever fill up leaves all the way so multiply by 2 just to be
2813 * closer to what we're really going to want to use.
2815 return div_u64(num_bytes, BTRFS_LEAF_DATA_SIZE(fs_info));
2819 * Takes the number of bytes to be csumm'ed and figures out how many leaves it
2820 * would require to store the csums for that many bytes.
2822 u64 btrfs_csum_bytes_to_leaves(struct btrfs_fs_info *fs_info, u64 csum_bytes)
2825 u64 num_csums_per_leaf;
2828 csum_size = BTRFS_MAX_ITEM_SIZE(fs_info);
2829 num_csums_per_leaf = div64_u64(csum_size,
2830 (u64)btrfs_super_csum_size(fs_info->super_copy));
2831 num_csums = div64_u64(csum_bytes, fs_info->sectorsize);
2832 num_csums += num_csums_per_leaf - 1;
2833 num_csums = div64_u64(num_csums, num_csums_per_leaf);
2837 bool btrfs_check_space_for_delayed_refs(struct btrfs_fs_info *fs_info)
2839 struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
2840 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
2844 spin_lock(&global_rsv->lock);
2845 reserved = global_rsv->reserved;
2846 spin_unlock(&global_rsv->lock);
2849 * Since the global reserve is just kind of magic we don't really want
2850 * to rely on it to save our bacon, so if our size is more than the
2851 * delayed_refs_rsv and the global rsv then it's time to think about
2854 spin_lock(&delayed_refs_rsv->lock);
2855 reserved += delayed_refs_rsv->reserved;
2856 if (delayed_refs_rsv->size >= reserved)
2858 spin_unlock(&delayed_refs_rsv->lock);
2862 int btrfs_should_throttle_delayed_refs(struct btrfs_trans_handle *trans)
2865 atomic_read(&trans->transaction->delayed_refs.num_entries);
2870 avg_runtime = trans->fs_info->avg_delayed_ref_runtime;
2871 val = num_entries * avg_runtime;
2872 if (val >= NSEC_PER_SEC)
2874 if (val >= NSEC_PER_SEC / 2)
2877 return btrfs_check_space_for_delayed_refs(trans->fs_info);
2880 struct async_delayed_refs {
2881 struct btrfs_root *root;
2886 struct completion wait;
2887 struct btrfs_work work;
2890 static inline struct async_delayed_refs *
2891 to_async_delayed_refs(struct btrfs_work *work)
2893 return container_of(work, struct async_delayed_refs, work);
2896 static void delayed_ref_async_start(struct btrfs_work *work)
2898 struct async_delayed_refs *async = to_async_delayed_refs(work);
2899 struct btrfs_trans_handle *trans;
2900 struct btrfs_fs_info *fs_info = async->root->fs_info;
2903 /* if the commit is already started, we don't need to wait here */
2904 if (btrfs_transaction_blocked(fs_info))
2907 trans = btrfs_join_transaction(async->root);
2908 if (IS_ERR(trans)) {
2909 async->error = PTR_ERR(trans);
2914 * trans->sync means that when we call end_transaction, we won't
2915 * wait on delayed refs
2919 /* Don't bother flushing if we got into a different transaction */
2920 if (trans->transid > async->transid)
2923 ret = btrfs_run_delayed_refs(trans, async->count);
2927 ret = btrfs_end_transaction(trans);
2928 if (ret && !async->error)
2932 complete(&async->wait);
2937 int btrfs_async_run_delayed_refs(struct btrfs_fs_info *fs_info,
2938 unsigned long count, u64 transid, int wait)
2940 struct async_delayed_refs *async;
2943 async = kmalloc(sizeof(*async), GFP_NOFS);
2947 async->root = fs_info->tree_root;
2948 async->count = count;
2950 async->transid = transid;
2955 init_completion(&async->wait);
2957 btrfs_init_work(&async->work, btrfs_extent_refs_helper,
2958 delayed_ref_async_start, NULL, NULL);
2960 btrfs_queue_work(fs_info->extent_workers, &async->work);
2963 wait_for_completion(&async->wait);
2972 * this starts processing the delayed reference count updates and
2973 * extent insertions we have queued up so far. count can be
2974 * 0, which means to process everything in the tree at the start
2975 * of the run (but not newly added entries), or it can be some target
2976 * number you'd like to process.
2978 * Returns 0 on success or if called with an aborted transaction
2979 * Returns <0 on error and aborts the transaction
2981 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2982 unsigned long count)
2984 struct btrfs_fs_info *fs_info = trans->fs_info;
2985 struct rb_node *node;
2986 struct btrfs_delayed_ref_root *delayed_refs;
2987 struct btrfs_delayed_ref_head *head;
2989 int run_all = count == (unsigned long)-1;
2991 /* We'll clean this up in btrfs_cleanup_transaction */
2995 if (test_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags))
2998 delayed_refs = &trans->transaction->delayed_refs;
3000 count = atomic_read(&delayed_refs->num_entries) * 2;
3003 #ifdef SCRAMBLE_DELAYED_REFS
3004 delayed_refs->run_delayed_start = find_middle(&delayed_refs->root);
3006 ret = __btrfs_run_delayed_refs(trans, count);
3008 btrfs_abort_transaction(trans, ret);
3013 btrfs_create_pending_block_groups(trans);
3015 spin_lock(&delayed_refs->lock);
3016 node = rb_first_cached(&delayed_refs->href_root);
3018 spin_unlock(&delayed_refs->lock);
3021 head = rb_entry(node, struct btrfs_delayed_ref_head,
3023 refcount_inc(&head->refs);
3024 spin_unlock(&delayed_refs->lock);
3026 /* Mutex was contended, block until it's released and retry. */
3027 mutex_lock(&head->mutex);
3028 mutex_unlock(&head->mutex);
3030 btrfs_put_delayed_ref_head(head);
3038 int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
3039 struct btrfs_fs_info *fs_info,
3040 u64 bytenr, u64 num_bytes, u64 flags,
3041 int level, int is_data)
3043 struct btrfs_delayed_extent_op *extent_op;
3046 extent_op = btrfs_alloc_delayed_extent_op();
3050 extent_op->flags_to_set = flags;
3051 extent_op->update_flags = true;
3052 extent_op->update_key = false;
3053 extent_op->is_data = is_data ? true : false;
3054 extent_op->level = level;
3056 ret = btrfs_add_delayed_extent_op(fs_info, trans, bytenr,
3057 num_bytes, extent_op);
3059 btrfs_free_delayed_extent_op(extent_op);
3063 static noinline int check_delayed_ref(struct btrfs_root *root,
3064 struct btrfs_path *path,
3065 u64 objectid, u64 offset, u64 bytenr)
3067 struct btrfs_delayed_ref_head *head;
3068 struct btrfs_delayed_ref_node *ref;
3069 struct btrfs_delayed_data_ref *data_ref;
3070 struct btrfs_delayed_ref_root *delayed_refs;
3071 struct btrfs_transaction *cur_trans;
3072 struct rb_node *node;
3075 spin_lock(&root->fs_info->trans_lock);
3076 cur_trans = root->fs_info->running_transaction;
3078 refcount_inc(&cur_trans->use_count);
3079 spin_unlock(&root->fs_info->trans_lock);
3083 delayed_refs = &cur_trans->delayed_refs;
3084 spin_lock(&delayed_refs->lock);
3085 head = btrfs_find_delayed_ref_head(delayed_refs, bytenr);
3087 spin_unlock(&delayed_refs->lock);
3088 btrfs_put_transaction(cur_trans);
3092 if (!mutex_trylock(&head->mutex)) {
3093 refcount_inc(&head->refs);
3094 spin_unlock(&delayed_refs->lock);
3096 btrfs_release_path(path);
3099 * Mutex was contended, block until it's released and let
3102 mutex_lock(&head->mutex);
3103 mutex_unlock(&head->mutex);
3104 btrfs_put_delayed_ref_head(head);
3105 btrfs_put_transaction(cur_trans);
3108 spin_unlock(&delayed_refs->lock);
3110 spin_lock(&head->lock);
3112 * XXX: We should replace this with a proper search function in the
3115 for (node = rb_first_cached(&head->ref_tree); node;
3116 node = rb_next(node)) {
3117 ref = rb_entry(node, struct btrfs_delayed_ref_node, ref_node);
3118 /* If it's a shared ref we know a cross reference exists */
3119 if (ref->type != BTRFS_EXTENT_DATA_REF_KEY) {
3124 data_ref = btrfs_delayed_node_to_data_ref(ref);
3127 * If our ref doesn't match the one we're currently looking at
3128 * then we have a cross reference.
3130 if (data_ref->root != root->root_key.objectid ||
3131 data_ref->objectid != objectid ||
3132 data_ref->offset != offset) {
3137 spin_unlock(&head->lock);
3138 mutex_unlock(&head->mutex);
3139 btrfs_put_transaction(cur_trans);
3143 static noinline int check_committed_ref(struct btrfs_root *root,
3144 struct btrfs_path *path,
3145 u64 objectid, u64 offset, u64 bytenr)
3147 struct btrfs_fs_info *fs_info = root->fs_info;
3148 struct btrfs_root *extent_root = fs_info->extent_root;
3149 struct extent_buffer *leaf;
3150 struct btrfs_extent_data_ref *ref;
3151 struct btrfs_extent_inline_ref *iref;
3152 struct btrfs_extent_item *ei;
3153 struct btrfs_key key;
3158 key.objectid = bytenr;
3159 key.offset = (u64)-1;
3160 key.type = BTRFS_EXTENT_ITEM_KEY;
3162 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
3165 BUG_ON(ret == 0); /* Corruption */
3168 if (path->slots[0] == 0)
3172 leaf = path->nodes[0];
3173 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
3175 if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY)
3179 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
3180 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
3182 if (item_size != sizeof(*ei) +
3183 btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY))
3186 if (btrfs_extent_generation(leaf, ei) <=
3187 btrfs_root_last_snapshot(&root->root_item))
3190 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
3192 type = btrfs_get_extent_inline_ref_type(leaf, iref, BTRFS_REF_TYPE_DATA);
3193 if (type != BTRFS_EXTENT_DATA_REF_KEY)
3196 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
3197 if (btrfs_extent_refs(leaf, ei) !=
3198 btrfs_extent_data_ref_count(leaf, ref) ||
3199 btrfs_extent_data_ref_root(leaf, ref) !=
3200 root->root_key.objectid ||
3201 btrfs_extent_data_ref_objectid(leaf, ref) != objectid ||
3202 btrfs_extent_data_ref_offset(leaf, ref) != offset)
3210 int btrfs_cross_ref_exist(struct btrfs_root *root, u64 objectid, u64 offset,
3213 struct btrfs_path *path;
3216 path = btrfs_alloc_path();
3221 ret = check_committed_ref(root, path, objectid,
3223 if (ret && ret != -ENOENT)
3226 ret = check_delayed_ref(root, path, objectid, offset, bytenr);
3227 } while (ret == -EAGAIN);
3230 btrfs_free_path(path);
3231 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
3236 static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
3237 struct btrfs_root *root,
3238 struct extent_buffer *buf,
3239 int full_backref, int inc)
3241 struct btrfs_fs_info *fs_info = root->fs_info;
3247 struct btrfs_key key;
3248 struct btrfs_file_extent_item *fi;
3252 int (*process_func)(struct btrfs_trans_handle *,
3253 struct btrfs_root *,
3254 u64, u64, u64, u64, u64, u64);
3257 if (btrfs_is_testing(fs_info))
3260 ref_root = btrfs_header_owner(buf);
3261 nritems = btrfs_header_nritems(buf);
3262 level = btrfs_header_level(buf);
3264 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state) && level == 0)
3268 process_func = btrfs_inc_extent_ref;
3270 process_func = btrfs_free_extent;
3273 parent = buf->start;
3277 for (i = 0; i < nritems; i++) {
3279 btrfs_item_key_to_cpu(buf, &key, i);
3280 if (key.type != BTRFS_EXTENT_DATA_KEY)
3282 fi = btrfs_item_ptr(buf, i,
3283 struct btrfs_file_extent_item);
3284 if (btrfs_file_extent_type(buf, fi) ==
3285 BTRFS_FILE_EXTENT_INLINE)
3287 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
3291 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
3292 key.offset -= btrfs_file_extent_offset(buf, fi);
3293 ret = process_func(trans, root, bytenr, num_bytes,
3294 parent, ref_root, key.objectid,
3299 bytenr = btrfs_node_blockptr(buf, i);
3300 num_bytes = fs_info->nodesize;
3301 ret = process_func(trans, root, bytenr, num_bytes,
3302 parent, ref_root, level - 1, 0);
3312 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
3313 struct extent_buffer *buf, int full_backref)
3315 return __btrfs_mod_ref(trans, root, buf, full_backref, 1);
3318 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
3319 struct extent_buffer *buf, int full_backref)
3321 return __btrfs_mod_ref(trans, root, buf, full_backref, 0);
3324 static int write_one_cache_group(struct btrfs_trans_handle *trans,
3325 struct btrfs_fs_info *fs_info,
3326 struct btrfs_path *path,
3327 struct btrfs_block_group_cache *cache)
3330 struct btrfs_root *extent_root = fs_info->extent_root;
3332 struct extent_buffer *leaf;
3334 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
3341 leaf = path->nodes[0];
3342 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
3343 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
3344 btrfs_mark_buffer_dirty(leaf);
3346 btrfs_release_path(path);
3351 static struct btrfs_block_group_cache *
3352 next_block_group(struct btrfs_fs_info *fs_info,
3353 struct btrfs_block_group_cache *cache)
3355 struct rb_node *node;
3357 spin_lock(&fs_info->block_group_cache_lock);
3359 /* If our block group was removed, we need a full search. */
3360 if (RB_EMPTY_NODE(&cache->cache_node)) {
3361 const u64 next_bytenr = cache->key.objectid + cache->key.offset;
3363 spin_unlock(&fs_info->block_group_cache_lock);
3364 btrfs_put_block_group(cache);
3365 cache = btrfs_lookup_first_block_group(fs_info, next_bytenr); return cache;
3367 node = rb_next(&cache->cache_node);
3368 btrfs_put_block_group(cache);
3370 cache = rb_entry(node, struct btrfs_block_group_cache,
3372 btrfs_get_block_group(cache);
3375 spin_unlock(&fs_info->block_group_cache_lock);
3379 static int cache_save_setup(struct btrfs_block_group_cache *block_group,
3380 struct btrfs_trans_handle *trans,
3381 struct btrfs_path *path)
3383 struct btrfs_fs_info *fs_info = block_group->fs_info;
3384 struct btrfs_root *root = fs_info->tree_root;
3385 struct inode *inode = NULL;
3386 struct extent_changeset *data_reserved = NULL;
3388 int dcs = BTRFS_DC_ERROR;
3394 * If this block group is smaller than 100 megs don't bother caching the
3397 if (block_group->key.offset < (100 * SZ_1M)) {
3398 spin_lock(&block_group->lock);
3399 block_group->disk_cache_state = BTRFS_DC_WRITTEN;
3400 spin_unlock(&block_group->lock);
3407 inode = lookup_free_space_inode(fs_info, block_group, path);
3408 if (IS_ERR(inode) && PTR_ERR(inode) != -ENOENT) {
3409 ret = PTR_ERR(inode);
3410 btrfs_release_path(path);
3414 if (IS_ERR(inode)) {
3418 if (block_group->ro)
3421 ret = create_free_space_inode(fs_info, trans, block_group,
3429 * We want to set the generation to 0, that way if anything goes wrong
3430 * from here on out we know not to trust this cache when we load up next
3433 BTRFS_I(inode)->generation = 0;
3434 ret = btrfs_update_inode(trans, root, inode);
3437 * So theoretically we could recover from this, simply set the
3438 * super cache generation to 0 so we know to invalidate the
3439 * cache, but then we'd have to keep track of the block groups
3440 * that fail this way so we know we _have_ to reset this cache
3441 * before the next commit or risk reading stale cache. So to
3442 * limit our exposure to horrible edge cases lets just abort the
3443 * transaction, this only happens in really bad situations
3446 btrfs_abort_transaction(trans, ret);
3451 /* We've already setup this transaction, go ahead and exit */
3452 if (block_group->cache_generation == trans->transid &&
3453 i_size_read(inode)) {
3454 dcs = BTRFS_DC_SETUP;
3458 if (i_size_read(inode) > 0) {
3459 ret = btrfs_check_trunc_cache_free_space(fs_info,
3460 &fs_info->global_block_rsv);
3464 ret = btrfs_truncate_free_space_cache(trans, NULL, inode);
3469 spin_lock(&block_group->lock);
3470 if (block_group->cached != BTRFS_CACHE_FINISHED ||
3471 !btrfs_test_opt(fs_info, SPACE_CACHE)) {
3473 * don't bother trying to write stuff out _if_
3474 * a) we're not cached,
3475 * b) we're with nospace_cache mount option,
3476 * c) we're with v2 space_cache (FREE_SPACE_TREE).
3478 dcs = BTRFS_DC_WRITTEN;
3479 spin_unlock(&block_group->lock);
3482 spin_unlock(&block_group->lock);
3485 * We hit an ENOSPC when setting up the cache in this transaction, just
3486 * skip doing the setup, we've already cleared the cache so we're safe.
3488 if (test_bit(BTRFS_TRANS_CACHE_ENOSPC, &trans->transaction->flags)) {
3494 * Try to preallocate enough space based on how big the block group is.
3495 * Keep in mind this has to include any pinned space which could end up
3496 * taking up quite a bit since it's not folded into the other space
3499 num_pages = div_u64(block_group->key.offset, SZ_256M);
3504 num_pages *= PAGE_SIZE;
3506 ret = btrfs_check_data_free_space(inode, &data_reserved, 0, num_pages);
3510 ret = btrfs_prealloc_file_range_trans(inode, trans, 0, 0, num_pages,
3511 num_pages, num_pages,
3514 * Our cache requires contiguous chunks so that we don't modify a bunch
3515 * of metadata or split extents when writing the cache out, which means
3516 * we can enospc if we are heavily fragmented in addition to just normal
3517 * out of space conditions. So if we hit this just skip setting up any
3518 * other block groups for this transaction, maybe we'll unpin enough
3519 * space the next time around.
3522 dcs = BTRFS_DC_SETUP;
3523 else if (ret == -ENOSPC)
3524 set_bit(BTRFS_TRANS_CACHE_ENOSPC, &trans->transaction->flags);
3529 btrfs_release_path(path);
3531 spin_lock(&block_group->lock);
3532 if (!ret && dcs == BTRFS_DC_SETUP)
3533 block_group->cache_generation = trans->transid;
3534 block_group->disk_cache_state = dcs;
3535 spin_unlock(&block_group->lock);
3537 extent_changeset_free(data_reserved);
3541 int btrfs_setup_space_cache(struct btrfs_trans_handle *trans,
3542 struct btrfs_fs_info *fs_info)
3544 struct btrfs_block_group_cache *cache, *tmp;
3545 struct btrfs_transaction *cur_trans = trans->transaction;
3546 struct btrfs_path *path;
3548 if (list_empty(&cur_trans->dirty_bgs) ||
3549 !btrfs_test_opt(fs_info, SPACE_CACHE))
3552 path = btrfs_alloc_path();
3556 /* Could add new block groups, use _safe just in case */
3557 list_for_each_entry_safe(cache, tmp, &cur_trans->dirty_bgs,
3559 if (cache->disk_cache_state == BTRFS_DC_CLEAR)
3560 cache_save_setup(cache, trans, path);
3563 btrfs_free_path(path);
3568 * transaction commit does final block group cache writeback during a
3569 * critical section where nothing is allowed to change the FS. This is
3570 * required in order for the cache to actually match the block group,
3571 * but can introduce a lot of latency into the commit.
3573 * So, btrfs_start_dirty_block_groups is here to kick off block group
3574 * cache IO. There's a chance we'll have to redo some of it if the
3575 * block group changes again during the commit, but it greatly reduces
3576 * the commit latency by getting rid of the easy block groups while
3577 * we're still allowing others to join the commit.
3579 int btrfs_start_dirty_block_groups(struct btrfs_trans_handle *trans)
3581 struct btrfs_fs_info *fs_info = trans->fs_info;
3582 struct btrfs_block_group_cache *cache;
3583 struct btrfs_transaction *cur_trans = trans->transaction;
3586 struct btrfs_path *path = NULL;
3588 struct list_head *io = &cur_trans->io_bgs;
3589 int num_started = 0;
3592 spin_lock(&cur_trans->dirty_bgs_lock);
3593 if (list_empty(&cur_trans->dirty_bgs)) {
3594 spin_unlock(&cur_trans->dirty_bgs_lock);
3597 list_splice_init(&cur_trans->dirty_bgs, &dirty);
3598 spin_unlock(&cur_trans->dirty_bgs_lock);
3602 * make sure all the block groups on our dirty list actually
3605 btrfs_create_pending_block_groups(trans);
3608 path = btrfs_alloc_path();
3614 * cache_write_mutex is here only to save us from balance or automatic
3615 * removal of empty block groups deleting this block group while we are
3616 * writing out the cache
3618 mutex_lock(&trans->transaction->cache_write_mutex);
3619 while (!list_empty(&dirty)) {
3620 bool drop_reserve = true;
3622 cache = list_first_entry(&dirty,
3623 struct btrfs_block_group_cache,
3626 * this can happen if something re-dirties a block
3627 * group that is already under IO. Just wait for it to
3628 * finish and then do it all again
3630 if (!list_empty(&cache->io_list)) {
3631 list_del_init(&cache->io_list);
3632 btrfs_wait_cache_io(trans, cache, path);
3633 btrfs_put_block_group(cache);
3638 * btrfs_wait_cache_io uses the cache->dirty_list to decide
3639 * if it should update the cache_state. Don't delete
3640 * until after we wait.
3642 * Since we're not running in the commit critical section
3643 * we need the dirty_bgs_lock to protect from update_block_group
3645 spin_lock(&cur_trans->dirty_bgs_lock);
3646 list_del_init(&cache->dirty_list);
3647 spin_unlock(&cur_trans->dirty_bgs_lock);
3651 cache_save_setup(cache, trans, path);
3653 if (cache->disk_cache_state == BTRFS_DC_SETUP) {
3654 cache->io_ctl.inode = NULL;
3655 ret = btrfs_write_out_cache(fs_info, trans,
3657 if (ret == 0 && cache->io_ctl.inode) {
3662 * The cache_write_mutex is protecting the
3663 * io_list, also refer to the definition of
3664 * btrfs_transaction::io_bgs for more details
3666 list_add_tail(&cache->io_list, io);
3669 * if we failed to write the cache, the
3670 * generation will be bad and life goes on
3676 ret = write_one_cache_group(trans, fs_info,
3679 * Our block group might still be attached to the list
3680 * of new block groups in the transaction handle of some
3681 * other task (struct btrfs_trans_handle->new_bgs). This
3682 * means its block group item isn't yet in the extent
3683 * tree. If this happens ignore the error, as we will
3684 * try again later in the critical section of the
3685 * transaction commit.
3687 if (ret == -ENOENT) {
3689 spin_lock(&cur_trans->dirty_bgs_lock);
3690 if (list_empty(&cache->dirty_list)) {
3691 list_add_tail(&cache->dirty_list,
3692 &cur_trans->dirty_bgs);
3693 btrfs_get_block_group(cache);
3694 drop_reserve = false;
3696 spin_unlock(&cur_trans->dirty_bgs_lock);
3698 btrfs_abort_transaction(trans, ret);
3702 /* if it's not on the io list, we need to put the block group */
3704 btrfs_put_block_group(cache);
3706 btrfs_delayed_refs_rsv_release(fs_info, 1);
3712 * Avoid blocking other tasks for too long. It might even save
3713 * us from writing caches for block groups that are going to be
3716 mutex_unlock(&trans->transaction->cache_write_mutex);
3717 mutex_lock(&trans->transaction->cache_write_mutex);
3719 mutex_unlock(&trans->transaction->cache_write_mutex);
3722 * go through delayed refs for all the stuff we've just kicked off
3723 * and then loop back (just once)
3725 ret = btrfs_run_delayed_refs(trans, 0);
3726 if (!ret && loops == 0) {
3728 spin_lock(&cur_trans->dirty_bgs_lock);
3729 list_splice_init(&cur_trans->dirty_bgs, &dirty);
3731 * dirty_bgs_lock protects us from concurrent block group
3732 * deletes too (not just cache_write_mutex).
3734 if (!list_empty(&dirty)) {
3735 spin_unlock(&cur_trans->dirty_bgs_lock);
3738 spin_unlock(&cur_trans->dirty_bgs_lock);
3739 } else if (ret < 0) {
3740 btrfs_cleanup_dirty_bgs(cur_trans, fs_info);
3743 btrfs_free_path(path);
3747 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
3748 struct btrfs_fs_info *fs_info)
3750 struct btrfs_block_group_cache *cache;
3751 struct btrfs_transaction *cur_trans = trans->transaction;
3754 struct btrfs_path *path;
3755 struct list_head *io = &cur_trans->io_bgs;
3756 int num_started = 0;
3758 path = btrfs_alloc_path();
3763 * Even though we are in the critical section of the transaction commit,
3764 * we can still have concurrent tasks adding elements to this
3765 * transaction's list of dirty block groups. These tasks correspond to
3766 * endio free space workers started when writeback finishes for a
3767 * space cache, which run inode.c:btrfs_finish_ordered_io(), and can
3768 * allocate new block groups as a result of COWing nodes of the root
3769 * tree when updating the free space inode. The writeback for the space
3770 * caches is triggered by an earlier call to
3771 * btrfs_start_dirty_block_groups() and iterations of the following
3773 * Also we want to do the cache_save_setup first and then run the
3774 * delayed refs to make sure we have the best chance at doing this all
3777 spin_lock(&cur_trans->dirty_bgs_lock);
3778 while (!list_empty(&cur_trans->dirty_bgs)) {
3779 cache = list_first_entry(&cur_trans->dirty_bgs,
3780 struct btrfs_block_group_cache,
3784 * this can happen if cache_save_setup re-dirties a block
3785 * group that is already under IO. Just wait for it to
3786 * finish and then do it all again
3788 if (!list_empty(&cache->io_list)) {
3789 spin_unlock(&cur_trans->dirty_bgs_lock);
3790 list_del_init(&cache->io_list);
3791 btrfs_wait_cache_io(trans, cache, path);
3792 btrfs_put_block_group(cache);
3793 spin_lock(&cur_trans->dirty_bgs_lock);
3797 * don't remove from the dirty list until after we've waited
3800 list_del_init(&cache->dirty_list);
3801 spin_unlock(&cur_trans->dirty_bgs_lock);
3804 cache_save_setup(cache, trans, path);
3807 ret = btrfs_run_delayed_refs(trans,
3808 (unsigned long) -1);
3810 if (!ret && cache->disk_cache_state == BTRFS_DC_SETUP) {
3811 cache->io_ctl.inode = NULL;
3812 ret = btrfs_write_out_cache(fs_info, trans,
3814 if (ret == 0 && cache->io_ctl.inode) {
3817 list_add_tail(&cache->io_list, io);
3820 * if we failed to write the cache, the
3821 * generation will be bad and life goes on
3827 ret = write_one_cache_group(trans, fs_info,
3830 * One of the free space endio workers might have
3831 * created a new block group while updating a free space
3832 * cache's inode (at inode.c:btrfs_finish_ordered_io())
3833 * and hasn't released its transaction handle yet, in
3834 * which case the new block group is still attached to
3835 * its transaction handle and its creation has not
3836 * finished yet (no block group item in the extent tree
3837 * yet, etc). If this is the case, wait for all free
3838 * space endio workers to finish and retry. This is a
3839 * a very rare case so no need for a more efficient and
3842 if (ret == -ENOENT) {
3843 wait_event(cur_trans->writer_wait,
3844 atomic_read(&cur_trans->num_writers) == 1);
3845 ret = write_one_cache_group(trans, fs_info,
3849 btrfs_abort_transaction(trans, ret);
3852 /* if its not on the io list, we need to put the block group */
3854 btrfs_put_block_group(cache);
3855 btrfs_delayed_refs_rsv_release(fs_info, 1);
3856 spin_lock(&cur_trans->dirty_bgs_lock);
3858 spin_unlock(&cur_trans->dirty_bgs_lock);
3861 * Refer to the definition of io_bgs member for details why it's safe
3862 * to use it without any locking
3864 while (!list_empty(io)) {
3865 cache = list_first_entry(io, struct btrfs_block_group_cache,
3867 list_del_init(&cache->io_list);
3868 btrfs_wait_cache_io(trans, cache, path);
3869 btrfs_put_block_group(cache);
3872 btrfs_free_path(path);
3876 int btrfs_extent_readonly(struct btrfs_fs_info *fs_info, u64 bytenr)
3878 struct btrfs_block_group_cache *block_group;
3881 block_group = btrfs_lookup_block_group(fs_info, bytenr);
3882 if (!block_group || block_group->ro)
3885 btrfs_put_block_group(block_group);
3889 bool btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr)
3891 struct btrfs_block_group_cache *bg;
3894 bg = btrfs_lookup_block_group(fs_info, bytenr);
3898 spin_lock(&bg->lock);
3902 atomic_inc(&bg->nocow_writers);
3903 spin_unlock(&bg->lock);
3905 /* no put on block group, done by btrfs_dec_nocow_writers */
3907 btrfs_put_block_group(bg);
3913 void btrfs_dec_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr)
3915 struct btrfs_block_group_cache *bg;
3917 bg = btrfs_lookup_block_group(fs_info, bytenr);
3919 if (atomic_dec_and_test(&bg->nocow_writers))
3920 wake_up_var(&bg->nocow_writers);
3922 * Once for our lookup and once for the lookup done by a previous call
3923 * to btrfs_inc_nocow_writers()
3925 btrfs_put_block_group(bg);
3926 btrfs_put_block_group(bg);
3929 void btrfs_wait_nocow_writers(struct btrfs_block_group_cache *bg)
3931 wait_var_event(&bg->nocow_writers, !atomic_read(&bg->nocow_writers));
3934 static const char *alloc_name(u64 flags)
3937 case BTRFS_BLOCK_GROUP_METADATA|BTRFS_BLOCK_GROUP_DATA:
3939 case BTRFS_BLOCK_GROUP_METADATA:
3941 case BTRFS_BLOCK_GROUP_DATA:
3943 case BTRFS_BLOCK_GROUP_SYSTEM:
3947 return "invalid-combination";
3951 static int create_space_info(struct btrfs_fs_info *info, u64 flags)
3954 struct btrfs_space_info *space_info;
3958 space_info = kzalloc(sizeof(*space_info), GFP_NOFS);
3962 ret = percpu_counter_init(&space_info->total_bytes_pinned, 0,
3969 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
3970 INIT_LIST_HEAD(&space_info->block_groups[i]);
3971 init_rwsem(&space_info->groups_sem);
3972 spin_lock_init(&space_info->lock);
3973 space_info->flags = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
3974 space_info->force_alloc = CHUNK_ALLOC_NO_FORCE;
3975 init_waitqueue_head(&space_info->wait);
3976 INIT_LIST_HEAD(&space_info->ro_bgs);
3977 INIT_LIST_HEAD(&space_info->tickets);
3978 INIT_LIST_HEAD(&space_info->priority_tickets);
3980 ret = kobject_init_and_add(&space_info->kobj, &space_info_ktype,
3981 info->space_info_kobj, "%s",
3982 alloc_name(space_info->flags));
3984 percpu_counter_destroy(&space_info->total_bytes_pinned);
3989 list_add_rcu(&space_info->list, &info->space_info);
3990 if (flags & BTRFS_BLOCK_GROUP_DATA)
3991 info->data_sinfo = space_info;
3996 static void update_space_info(struct btrfs_fs_info *info, u64 flags,
3997 u64 total_bytes, u64 bytes_used,
3999 struct btrfs_space_info **space_info)
4001 struct btrfs_space_info *found;
4004 factor = btrfs_bg_type_to_factor(flags);
4006 found = __find_space_info(info, flags);
4008 spin_lock(&found->lock);
4009 found->total_bytes += total_bytes;
4010 found->disk_total += total_bytes * factor;
4011 found->bytes_used += bytes_used;
4012 found->disk_used += bytes_used * factor;
4013 found->bytes_readonly += bytes_readonly;
4014 if (total_bytes > 0)
4016 space_info_add_new_bytes(info, found, total_bytes -
4017 bytes_used - bytes_readonly);
4018 spin_unlock(&found->lock);
4019 *space_info = found;
4022 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
4024 u64 extra_flags = chunk_to_extended(flags) &
4025 BTRFS_EXTENDED_PROFILE_MASK;
4027 write_seqlock(&fs_info->profiles_lock);
4028 if (flags & BTRFS_BLOCK_GROUP_DATA)
4029 fs_info->avail_data_alloc_bits |= extra_flags;
4030 if (flags & BTRFS_BLOCK_GROUP_METADATA)
4031 fs_info->avail_metadata_alloc_bits |= extra_flags;
4032 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
4033 fs_info->avail_system_alloc_bits |= extra_flags;
4034 write_sequnlock(&fs_info->profiles_lock);
4038 * returns target flags in extended format or 0 if restripe for this
4039 * chunk_type is not in progress
4041 * should be called with balance_lock held
4043 static u64 get_restripe_target(struct btrfs_fs_info *fs_info, u64 flags)
4045 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4051 if (flags & BTRFS_BLOCK_GROUP_DATA &&
4052 bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) {
4053 target = BTRFS_BLOCK_GROUP_DATA | bctl->data.target;
4054 } else if (flags & BTRFS_BLOCK_GROUP_SYSTEM &&
4055 bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
4056 target = BTRFS_BLOCK_GROUP_SYSTEM | bctl->sys.target;
4057 } else if (flags & BTRFS_BLOCK_GROUP_METADATA &&
4058 bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) {
4059 target = BTRFS_BLOCK_GROUP_METADATA | bctl->meta.target;
4066 * @flags: available profiles in extended format (see ctree.h)
4068 * Returns reduced profile in chunk format. If profile changing is in
4069 * progress (either running or paused) picks the target profile (if it's
4070 * already available), otherwise falls back to plain reducing.
4072 static u64 btrfs_reduce_alloc_profile(struct btrfs_fs_info *fs_info, u64 flags)
4074 u64 num_devices = fs_info->fs_devices->rw_devices;
4080 * see if restripe for this chunk_type is in progress, if so
4081 * try to reduce to the target profile
4083 spin_lock(&fs_info->balance_lock);
4084 target = get_restripe_target(fs_info, flags);
4086 /* pick target profile only if it's already available */
4087 if ((flags & target) & BTRFS_EXTENDED_PROFILE_MASK) {
4088 spin_unlock(&fs_info->balance_lock);
4089 return extended_to_chunk(target);
4092 spin_unlock(&fs_info->balance_lock);
4094 /* First, mask out the RAID levels which aren't possible */
4095 for (raid_type = 0; raid_type < BTRFS_NR_RAID_TYPES; raid_type++) {
4096 if (num_devices >= btrfs_raid_array[raid_type].devs_min)
4097 allowed |= btrfs_raid_array[raid_type].bg_flag;
4101 if (allowed & BTRFS_BLOCK_GROUP_RAID6)
4102 allowed = BTRFS_BLOCK_GROUP_RAID6;
4103 else if (allowed & BTRFS_BLOCK_GROUP_RAID5)
4104 allowed = BTRFS_BLOCK_GROUP_RAID5;
4105 else if (allowed & BTRFS_BLOCK_GROUP_RAID10)
4106 allowed = BTRFS_BLOCK_GROUP_RAID10;
4107 else if (allowed & BTRFS_BLOCK_GROUP_RAID1)
4108 allowed = BTRFS_BLOCK_GROUP_RAID1;
4109 else if (allowed & BTRFS_BLOCK_GROUP_RAID0)
4110 allowed = BTRFS_BLOCK_GROUP_RAID0;
4112 flags &= ~BTRFS_BLOCK_GROUP_PROFILE_MASK;
4114 return extended_to_chunk(flags | allowed);
4117 static u64 get_alloc_profile(struct btrfs_fs_info *fs_info, u64 orig_flags)
4124 seq = read_seqbegin(&fs_info->profiles_lock);
4126 if (flags & BTRFS_BLOCK_GROUP_DATA)
4127 flags |= fs_info->avail_data_alloc_bits;
4128 else if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
4129 flags |= fs_info->avail_system_alloc_bits;
4130 else if (flags & BTRFS_BLOCK_GROUP_METADATA)
4131 flags |= fs_info->avail_metadata_alloc_bits;
4132 } while (read_seqretry(&fs_info->profiles_lock, seq));
4134 return btrfs_reduce_alloc_profile(fs_info, flags);
4137 static u64 get_alloc_profile_by_root(struct btrfs_root *root, int data)
4139 struct btrfs_fs_info *fs_info = root->fs_info;
4144 flags = BTRFS_BLOCK_GROUP_DATA;
4145 else if (root == fs_info->chunk_root)
4146 flags = BTRFS_BLOCK_GROUP_SYSTEM;
4148 flags = BTRFS_BLOCK_GROUP_METADATA;
4150 ret = get_alloc_profile(fs_info, flags);
4154 u64 btrfs_data_alloc_profile(struct btrfs_fs_info *fs_info)
4156 return get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_DATA);
4159 u64 btrfs_metadata_alloc_profile(struct btrfs_fs_info *fs_info)
4161 return get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_METADATA);
4164 u64 btrfs_system_alloc_profile(struct btrfs_fs_info *fs_info)
4166 return get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
4169 static u64 btrfs_space_info_used(struct btrfs_space_info *s_info,
4170 bool may_use_included)
4173 return s_info->bytes_used + s_info->bytes_reserved +
4174 s_info->bytes_pinned + s_info->bytes_readonly +
4175 (may_use_included ? s_info->bytes_may_use : 0);
4178 int btrfs_alloc_data_chunk_ondemand(struct btrfs_inode *inode, u64 bytes)
4180 struct btrfs_root *root = inode->root;
4181 struct btrfs_fs_info *fs_info = root->fs_info;
4182 struct btrfs_space_info *data_sinfo = fs_info->data_sinfo;
4185 int need_commit = 2;
4186 int have_pinned_space;
4188 /* make sure bytes are sectorsize aligned */
4189 bytes = ALIGN(bytes, fs_info->sectorsize);
4191 if (btrfs_is_free_space_inode(inode)) {
4193 ASSERT(current->journal_info);
4197 /* make sure we have enough space to handle the data first */
4198 spin_lock(&data_sinfo->lock);
4199 used = btrfs_space_info_used(data_sinfo, true);
4201 if (used + bytes > data_sinfo->total_bytes) {
4202 struct btrfs_trans_handle *trans;
4205 * if we don't have enough free bytes in this space then we need
4206 * to alloc a new chunk.
4208 if (!data_sinfo->full) {
4211 data_sinfo->force_alloc = CHUNK_ALLOC_FORCE;
4212 spin_unlock(&data_sinfo->lock);
4214 alloc_target = btrfs_data_alloc_profile(fs_info);
4216 * It is ugly that we don't call nolock join
4217 * transaction for the free space inode case here.
4218 * But it is safe because we only do the data space
4219 * reservation for the free space cache in the
4220 * transaction context, the common join transaction
4221 * just increase the counter of the current transaction
4222 * handler, doesn't try to acquire the trans_lock of
4225 trans = btrfs_join_transaction(root);
4227 return PTR_ERR(trans);
4229 ret = do_chunk_alloc(trans, alloc_target,
4230 CHUNK_ALLOC_NO_FORCE);
4231 btrfs_end_transaction(trans);
4236 have_pinned_space = 1;
4245 * If we don't have enough pinned space to deal with this
4246 * allocation, and no removed chunk in current transaction,
4247 * don't bother committing the transaction.
4249 have_pinned_space = __percpu_counter_compare(
4250 &data_sinfo->total_bytes_pinned,
4251 used + bytes - data_sinfo->total_bytes,
4252 BTRFS_TOTAL_BYTES_PINNED_BATCH);
4253 spin_unlock(&data_sinfo->lock);
4255 /* commit the current transaction and try again */
4260 if (need_commit > 0) {
4261 btrfs_start_delalloc_roots(fs_info, -1);
4262 btrfs_wait_ordered_roots(fs_info, U64_MAX, 0,
4266 trans = btrfs_join_transaction(root);
4268 return PTR_ERR(trans);
4269 if (have_pinned_space >= 0 ||
4270 test_bit(BTRFS_TRANS_HAVE_FREE_BGS,
4271 &trans->transaction->flags) ||
4273 ret = btrfs_commit_transaction(trans);
4277 * The cleaner kthread might still be doing iput
4278 * operations. Wait for it to finish so that
4279 * more space is released. We don't need to
4280 * explicitly run the delayed iputs here because
4281 * the commit_transaction would have woken up
4284 ret = btrfs_wait_on_delayed_iputs(fs_info);
4289 btrfs_end_transaction(trans);
4293 trace_btrfs_space_reservation(fs_info,
4294 "space_info:enospc",
4295 data_sinfo->flags, bytes, 1);
4298 update_bytes_may_use(data_sinfo, bytes);
4299 trace_btrfs_space_reservation(fs_info, "space_info",
4300 data_sinfo->flags, bytes, 1);
4301 spin_unlock(&data_sinfo->lock);
4306 int btrfs_check_data_free_space(struct inode *inode,
4307 struct extent_changeset **reserved, u64 start, u64 len)
4309 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4312 /* align the range */
4313 len = round_up(start + len, fs_info->sectorsize) -
4314 round_down(start, fs_info->sectorsize);
4315 start = round_down(start, fs_info->sectorsize);
4317 ret = btrfs_alloc_data_chunk_ondemand(BTRFS_I(inode), len);
4321 /* Use new btrfs_qgroup_reserve_data to reserve precious data space. */
4322 ret = btrfs_qgroup_reserve_data(inode, reserved, start, len);
4324 btrfs_free_reserved_data_space_noquota(inode, start, len);
4331 * Called if we need to clear a data reservation for this inode
4332 * Normally in a error case.
4334 * This one will *NOT* use accurate qgroup reserved space API, just for case
4335 * which we can't sleep and is sure it won't affect qgroup reserved space.
4336 * Like clear_bit_hook().
4338 void btrfs_free_reserved_data_space_noquota(struct inode *inode, u64 start,
4341 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4342 struct btrfs_space_info *data_sinfo;
4344 /* Make sure the range is aligned to sectorsize */
4345 len = round_up(start + len, fs_info->sectorsize) -
4346 round_down(start, fs_info->sectorsize);
4347 start = round_down(start, fs_info->sectorsize);
4349 data_sinfo = fs_info->data_sinfo;
4350 spin_lock(&data_sinfo->lock);
4351 update_bytes_may_use(data_sinfo, -len);
4352 trace_btrfs_space_reservation(fs_info, "space_info",
4353 data_sinfo->flags, len, 0);
4354 spin_unlock(&data_sinfo->lock);
4358 * Called if we need to clear a data reservation for this inode
4359 * Normally in a error case.
4361 * This one will handle the per-inode data rsv map for accurate reserved
4364 void btrfs_free_reserved_data_space(struct inode *inode,
4365 struct extent_changeset *reserved, u64 start, u64 len)
4367 struct btrfs_root *root = BTRFS_I(inode)->root;
4369 /* Make sure the range is aligned to sectorsize */
4370 len = round_up(start + len, root->fs_info->sectorsize) -
4371 round_down(start, root->fs_info->sectorsize);
4372 start = round_down(start, root->fs_info->sectorsize);
4374 btrfs_free_reserved_data_space_noquota(inode, start, len);
4375 btrfs_qgroup_free_data(inode, reserved, start, len);
4378 static void force_metadata_allocation(struct btrfs_fs_info *info)
4380 struct list_head *head = &info->space_info;
4381 struct btrfs_space_info *found;
4384 list_for_each_entry_rcu(found, head, list) {
4385 if (found->flags & BTRFS_BLOCK_GROUP_METADATA)
4386 found->force_alloc = CHUNK_ALLOC_FORCE;
4391 static inline u64 calc_global_rsv_need_space(struct btrfs_block_rsv *global)
4393 return (global->size << 1);
4396 static int should_alloc_chunk(struct btrfs_fs_info *fs_info,
4397 struct btrfs_space_info *sinfo, int force)
4399 u64 bytes_used = btrfs_space_info_used(sinfo, false);
4402 if (force == CHUNK_ALLOC_FORCE)
4406 * in limited mode, we want to have some free space up to
4407 * about 1% of the FS size.
4409 if (force == CHUNK_ALLOC_LIMITED) {
4410 thresh = btrfs_super_total_bytes(fs_info->super_copy);
4411 thresh = max_t(u64, SZ_64M, div_factor_fine(thresh, 1));
4413 if (sinfo->total_bytes - bytes_used < thresh)
4417 if (bytes_used + SZ_2M < div_factor(sinfo->total_bytes, 8))
4422 static u64 get_profile_num_devs(struct btrfs_fs_info *fs_info, u64 type)
4426 if (type & (BTRFS_BLOCK_GROUP_RAID10 |
4427 BTRFS_BLOCK_GROUP_RAID0 |
4428 BTRFS_BLOCK_GROUP_RAID5 |
4429 BTRFS_BLOCK_GROUP_RAID6))
4430 num_dev = fs_info->fs_devices->rw_devices;
4431 else if (type & BTRFS_BLOCK_GROUP_RAID1)
4434 num_dev = 1; /* DUP or single */
4440 * If @is_allocation is true, reserve space in the system space info necessary
4441 * for allocating a chunk, otherwise if it's false, reserve space necessary for
4444 void check_system_chunk(struct btrfs_trans_handle *trans, u64 type)
4446 struct btrfs_fs_info *fs_info = trans->fs_info;
4447 struct btrfs_space_info *info;
4454 * Needed because we can end up allocating a system chunk and for an
4455 * atomic and race free space reservation in the chunk block reserve.
4457 lockdep_assert_held(&fs_info->chunk_mutex);
4459 info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
4460 spin_lock(&info->lock);
4461 left = info->total_bytes - btrfs_space_info_used(info, true);
4462 spin_unlock(&info->lock);
4464 num_devs = get_profile_num_devs(fs_info, type);
4466 /* num_devs device items to update and 1 chunk item to add or remove */
4467 thresh = btrfs_calc_trunc_metadata_size(fs_info, num_devs) +
4468 btrfs_calc_trans_metadata_size(fs_info, 1);
4470 if (left < thresh && btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
4471 btrfs_info(fs_info, "left=%llu, need=%llu, flags=%llu",
4472 left, thresh, type);
4473 dump_space_info(fs_info, info, 0, 0);
4476 if (left < thresh) {
4477 u64 flags = btrfs_system_alloc_profile(fs_info);
4480 * Ignore failure to create system chunk. We might end up not
4481 * needing it, as we might not need to COW all nodes/leafs from
4482 * the paths we visit in the chunk tree (they were already COWed
4483 * or created in the current transaction for example).
4485 ret = btrfs_alloc_chunk(trans, flags);
4489 ret = btrfs_block_rsv_add(fs_info->chunk_root,
4490 &fs_info->chunk_block_rsv,
4491 thresh, BTRFS_RESERVE_NO_FLUSH);
4493 trans->chunk_bytes_reserved += thresh;
4498 * If force is CHUNK_ALLOC_FORCE:
4499 * - return 1 if it successfully allocates a chunk,
4500 * - return errors including -ENOSPC otherwise.
4501 * If force is NOT CHUNK_ALLOC_FORCE:
4502 * - return 0 if it doesn't need to allocate a new chunk,
4503 * - return 1 if it successfully allocates a chunk,
4504 * - return errors including -ENOSPC otherwise.
4506 static int do_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags,
4509 struct btrfs_fs_info *fs_info = trans->fs_info;
4510 struct btrfs_space_info *space_info;
4511 bool wait_for_alloc = false;
4512 bool should_alloc = false;
4515 /* Don't re-enter if we're already allocating a chunk */
4516 if (trans->allocating_chunk)
4519 space_info = __find_space_info(fs_info, flags);
4523 spin_lock(&space_info->lock);
4524 if (force < space_info->force_alloc)
4525 force = space_info->force_alloc;
4526 should_alloc = should_alloc_chunk(fs_info, space_info, force);
4527 if (space_info->full) {
4528 /* No more free physical space */
4533 spin_unlock(&space_info->lock);
4535 } else if (!should_alloc) {
4536 spin_unlock(&space_info->lock);
4538 } else if (space_info->chunk_alloc) {
4540 * Someone is already allocating, so we need to block
4541 * until this someone is finished and then loop to
4542 * recheck if we should continue with our allocation
4545 wait_for_alloc = true;
4546 spin_unlock(&space_info->lock);
4547 mutex_lock(&fs_info->chunk_mutex);
4548 mutex_unlock(&fs_info->chunk_mutex);
4550 /* Proceed with allocation */
4551 space_info->chunk_alloc = 1;
4552 wait_for_alloc = false;
4553 spin_unlock(&space_info->lock);
4557 } while (wait_for_alloc);
4559 mutex_lock(&fs_info->chunk_mutex);
4560 trans->allocating_chunk = true;
4563 * If we have mixed data/metadata chunks we want to make sure we keep
4564 * allocating mixed chunks instead of individual chunks.
4566 if (btrfs_mixed_space_info(space_info))
4567 flags |= (BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA);
4570 * if we're doing a data chunk, go ahead and make sure that
4571 * we keep a reasonable number of metadata chunks allocated in the
4574 if (flags & BTRFS_BLOCK_GROUP_DATA && fs_info->metadata_ratio) {
4575 fs_info->data_chunk_allocations++;
4576 if (!(fs_info->data_chunk_allocations %
4577 fs_info->metadata_ratio))
4578 force_metadata_allocation(fs_info);
4582 * Check if we have enough space in SYSTEM chunk because we may need
4583 * to update devices.
4585 check_system_chunk(trans, flags);
4587 ret = btrfs_alloc_chunk(trans, flags);
4588 trans->allocating_chunk = false;
4590 spin_lock(&space_info->lock);
4593 space_info->full = 1;
4598 space_info->max_extent_size = 0;
4601 space_info->force_alloc = CHUNK_ALLOC_NO_FORCE;
4603 space_info->chunk_alloc = 0;
4604 spin_unlock(&space_info->lock);
4605 mutex_unlock(&fs_info->chunk_mutex);
4607 * When we allocate a new chunk we reserve space in the chunk block
4608 * reserve to make sure we can COW nodes/leafs in the chunk tree or
4609 * add new nodes/leafs to it if we end up needing to do it when
4610 * inserting the chunk item and updating device items as part of the
4611 * second phase of chunk allocation, performed by
4612 * btrfs_finish_chunk_alloc(). So make sure we don't accumulate a
4613 * large number of new block groups to create in our transaction
4614 * handle's new_bgs list to avoid exhausting the chunk block reserve
4615 * in extreme cases - like having a single transaction create many new
4616 * block groups when starting to write out the free space caches of all
4617 * the block groups that were made dirty during the lifetime of the
4620 if (trans->chunk_bytes_reserved >= (u64)SZ_2M)
4621 btrfs_create_pending_block_groups(trans);
4626 static int can_overcommit(struct btrfs_fs_info *fs_info,
4627 struct btrfs_space_info *space_info, u64 bytes,
4628 enum btrfs_reserve_flush_enum flush,
4631 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
4638 /* Don't overcommit when in mixed mode. */
4639 if (space_info->flags & BTRFS_BLOCK_GROUP_DATA)
4643 profile = btrfs_system_alloc_profile(fs_info);
4645 profile = btrfs_metadata_alloc_profile(fs_info);
4647 used = btrfs_space_info_used(space_info, false);
4650 * We only want to allow over committing if we have lots of actual space
4651 * free, but if we don't have enough space to handle the global reserve
4652 * space then we could end up having a real enospc problem when trying
4653 * to allocate a chunk or some other such important allocation.
4655 spin_lock(&global_rsv->lock);
4656 space_size = calc_global_rsv_need_space(global_rsv);
4657 spin_unlock(&global_rsv->lock);
4658 if (used + space_size >= space_info->total_bytes)
4661 used += space_info->bytes_may_use;
4663 avail = atomic64_read(&fs_info->free_chunk_space);
4666 * If we have dup, raid1 or raid10 then only half of the free
4667 * space is actually usable. For raid56, the space info used
4668 * doesn't include the parity drive, so we don't have to
4671 factor = btrfs_bg_type_to_factor(profile);
4672 avail = div_u64(avail, factor);
4675 * If we aren't flushing all things, let us overcommit up to
4676 * 1/2th of the space. If we can flush, don't let us overcommit
4677 * too much, let it overcommit up to 1/8 of the space.
4679 if (flush == BTRFS_RESERVE_FLUSH_ALL)
4684 if (used + bytes < space_info->total_bytes + avail)
4689 static void btrfs_writeback_inodes_sb_nr(struct btrfs_fs_info *fs_info,
4690 unsigned long nr_pages, int nr_items)
4692 struct super_block *sb = fs_info->sb;
4694 if (down_read_trylock(&sb->s_umount)) {
4695 writeback_inodes_sb_nr(sb, nr_pages, WB_REASON_FS_FREE_SPACE);
4696 up_read(&sb->s_umount);
4699 * We needn't worry the filesystem going from r/w to r/o though
4700 * we don't acquire ->s_umount mutex, because the filesystem
4701 * should guarantee the delalloc inodes list be empty after
4702 * the filesystem is readonly(all dirty pages are written to
4705 btrfs_start_delalloc_roots(fs_info, nr_items);
4706 if (!current->journal_info)
4707 btrfs_wait_ordered_roots(fs_info, nr_items, 0, (u64)-1);
4711 static inline u64 calc_reclaim_items_nr(struct btrfs_fs_info *fs_info,
4717 bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
4718 nr = div64_u64(to_reclaim, bytes);
4724 #define EXTENT_SIZE_PER_ITEM SZ_256K
4727 * shrink metadata reservation for delalloc
4729 static void shrink_delalloc(struct btrfs_fs_info *fs_info, u64 to_reclaim,
4730 u64 orig, bool wait_ordered)
4732 struct btrfs_space_info *space_info;
4733 struct btrfs_trans_handle *trans;
4738 unsigned long nr_pages;
4741 /* Calc the number of the pages we need flush for space reservation */
4742 items = calc_reclaim_items_nr(fs_info, to_reclaim);
4743 to_reclaim = items * EXTENT_SIZE_PER_ITEM;
4745 trans = (struct btrfs_trans_handle *)current->journal_info;
4746 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
4748 delalloc_bytes = percpu_counter_sum_positive(
4749 &fs_info->delalloc_bytes);
4750 if (delalloc_bytes == 0) {
4754 btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1);
4759 while (delalloc_bytes && loops < 3) {
4760 nr_pages = min(delalloc_bytes, to_reclaim) >> PAGE_SHIFT;
4763 * Triggers inode writeback for up to nr_pages. This will invoke
4764 * ->writepages callback and trigger delalloc filling
4765 * (btrfs_run_delalloc_range()).
4767 btrfs_writeback_inodes_sb_nr(fs_info, nr_pages, items);
4770 * We need to wait for the compressed pages to start before
4773 async_pages = atomic_read(&fs_info->async_delalloc_pages);
4778 * Calculate how many compressed pages we want to be written
4779 * before we continue. I.e if there are more async pages than we
4780 * require wait_event will wait until nr_pages are written.
4782 if (async_pages <= nr_pages)
4785 async_pages -= nr_pages;
4787 wait_event(fs_info->async_submit_wait,
4788 atomic_read(&fs_info->async_delalloc_pages) <=
4791 spin_lock(&space_info->lock);
4792 if (list_empty(&space_info->tickets) &&
4793 list_empty(&space_info->priority_tickets)) {
4794 spin_unlock(&space_info->lock);
4797 spin_unlock(&space_info->lock);
4800 if (wait_ordered && !trans) {
4801 btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1);
4803 time_left = schedule_timeout_killable(1);
4807 delalloc_bytes = percpu_counter_sum_positive(
4808 &fs_info->delalloc_bytes);
4812 struct reserve_ticket {
4816 struct list_head list;
4817 wait_queue_head_t wait;
4821 * maybe_commit_transaction - possibly commit the transaction if its ok to
4822 * @root - the root we're allocating for
4823 * @bytes - the number of bytes we want to reserve
4824 * @force - force the commit
4826 * This will check to make sure that committing the transaction will actually
4827 * get us somewhere and then commit the transaction if it does. Otherwise it
4828 * will return -ENOSPC.
4830 static int may_commit_transaction(struct btrfs_fs_info *fs_info,
4831 struct btrfs_space_info *space_info)
4833 struct reserve_ticket *ticket = NULL;
4834 struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_block_rsv;
4835 struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
4836 struct btrfs_trans_handle *trans;
4838 u64 reclaim_bytes = 0;
4840 trans = (struct btrfs_trans_handle *)current->journal_info;
4844 spin_lock(&space_info->lock);
4845 if (!list_empty(&space_info->priority_tickets))
4846 ticket = list_first_entry(&space_info->priority_tickets,
4847 struct reserve_ticket, list);
4848 else if (!list_empty(&space_info->tickets))
4849 ticket = list_first_entry(&space_info->tickets,
4850 struct reserve_ticket, list);
4851 bytes_needed = (ticket) ? ticket->bytes : 0;
4852 spin_unlock(&space_info->lock);
4857 trans = btrfs_join_transaction(fs_info->extent_root);
4859 return PTR_ERR(trans);
4862 * See if there is enough pinned space to make this reservation, or if
4863 * we have block groups that are going to be freed, allowing us to
4864 * possibly do a chunk allocation the next loop through.
4866 if (test_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags) ||
4867 __percpu_counter_compare(&space_info->total_bytes_pinned,
4869 BTRFS_TOTAL_BYTES_PINNED_BATCH) >= 0)
4873 * See if there is some space in the delayed insertion reservation for
4876 if (space_info != delayed_rsv->space_info)
4879 spin_lock(&delayed_rsv->lock);
4880 reclaim_bytes += delayed_rsv->reserved;
4881 spin_unlock(&delayed_rsv->lock);
4883 spin_lock(&delayed_refs_rsv->lock);
4884 reclaim_bytes += delayed_refs_rsv->reserved;
4885 spin_unlock(&delayed_refs_rsv->lock);
4886 if (reclaim_bytes >= bytes_needed)
4888 bytes_needed -= reclaim_bytes;
4890 if (__percpu_counter_compare(&space_info->total_bytes_pinned,
4892 BTRFS_TOTAL_BYTES_PINNED_BATCH) < 0)
4896 return btrfs_commit_transaction(trans);
4898 btrfs_end_transaction(trans);
4903 * Try to flush some data based on policy set by @state. This is only advisory
4904 * and may fail for various reasons. The caller is supposed to examine the
4905 * state of @space_info to detect the outcome.
4907 static void flush_space(struct btrfs_fs_info *fs_info,
4908 struct btrfs_space_info *space_info, u64 num_bytes,
4911 struct btrfs_root *root = fs_info->extent_root;
4912 struct btrfs_trans_handle *trans;
4917 case FLUSH_DELAYED_ITEMS_NR:
4918 case FLUSH_DELAYED_ITEMS:
4919 if (state == FLUSH_DELAYED_ITEMS_NR)
4920 nr = calc_reclaim_items_nr(fs_info, num_bytes) * 2;
4924 trans = btrfs_join_transaction(root);
4925 if (IS_ERR(trans)) {
4926 ret = PTR_ERR(trans);
4929 ret = btrfs_run_delayed_items_nr(trans, nr);
4930 btrfs_end_transaction(trans);
4932 case FLUSH_DELALLOC:
4933 case FLUSH_DELALLOC_WAIT:
4934 shrink_delalloc(fs_info, num_bytes * 2, num_bytes,
4935 state == FLUSH_DELALLOC_WAIT);
4937 case FLUSH_DELAYED_REFS_NR:
4938 case FLUSH_DELAYED_REFS:
4939 trans = btrfs_join_transaction(root);
4940 if (IS_ERR(trans)) {
4941 ret = PTR_ERR(trans);
4944 if (state == FLUSH_DELAYED_REFS_NR)
4945 nr = calc_reclaim_items_nr(fs_info, num_bytes);
4948 btrfs_run_delayed_refs(trans, nr);
4949 btrfs_end_transaction(trans);
4952 case ALLOC_CHUNK_FORCE:
4953 trans = btrfs_join_transaction(root);
4954 if (IS_ERR(trans)) {
4955 ret = PTR_ERR(trans);
4958 ret = do_chunk_alloc(trans,
4959 btrfs_metadata_alloc_profile(fs_info),
4960 (state == ALLOC_CHUNK) ?
4961 CHUNK_ALLOC_NO_FORCE : CHUNK_ALLOC_FORCE);
4962 btrfs_end_transaction(trans);
4963 if (ret > 0 || ret == -ENOSPC)
4968 * If we have pending delayed iputs then we could free up a
4969 * bunch of pinned space, so make sure we run the iputs before
4970 * we do our pinned bytes check below.
4972 btrfs_run_delayed_iputs(fs_info);
4973 btrfs_wait_on_delayed_iputs(fs_info);
4975 ret = may_commit_transaction(fs_info, space_info);
4982 trace_btrfs_flush_space(fs_info, space_info->flags, num_bytes, state,
4988 btrfs_calc_reclaim_metadata_size(struct btrfs_fs_info *fs_info,
4989 struct btrfs_space_info *space_info,
4992 struct reserve_ticket *ticket;
4997 list_for_each_entry(ticket, &space_info->tickets, list)
4998 to_reclaim += ticket->bytes;
4999 list_for_each_entry(ticket, &space_info->priority_tickets, list)
5000 to_reclaim += ticket->bytes;
5004 to_reclaim = min_t(u64, num_online_cpus() * SZ_1M, SZ_16M);
5005 if (can_overcommit(fs_info, space_info, to_reclaim,
5006 BTRFS_RESERVE_FLUSH_ALL, system_chunk))
5009 used = btrfs_space_info_used(space_info, true);
5011 if (can_overcommit(fs_info, space_info, SZ_1M,
5012 BTRFS_RESERVE_FLUSH_ALL, system_chunk))
5013 expected = div_factor_fine(space_info->total_bytes, 95);
5015 expected = div_factor_fine(space_info->total_bytes, 90);
5017 if (used > expected)
5018 to_reclaim = used - expected;
5021 to_reclaim = min(to_reclaim, space_info->bytes_may_use +
5022 space_info->bytes_reserved);
5026 static inline int need_do_async_reclaim(struct btrfs_fs_info *fs_info,
5027 struct btrfs_space_info *space_info,
5028 u64 used, bool system_chunk)
5030 u64 thresh = div_factor_fine(space_info->total_bytes, 98);
5032 /* If we're just plain full then async reclaim just slows us down. */
5033 if ((space_info->bytes_used + space_info->bytes_reserved) >= thresh)
5036 if (!btrfs_calc_reclaim_metadata_size(fs_info, space_info,
5040 return (used >= thresh && !btrfs_fs_closing(fs_info) &&
5041 !test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state));
5044 static bool wake_all_tickets(struct list_head *head)
5046 struct reserve_ticket *ticket;
5048 while (!list_empty(head)) {
5049 ticket = list_first_entry(head, struct reserve_ticket, list);
5050 list_del_init(&ticket->list);
5051 ticket->error = -ENOSPC;
5052 wake_up(&ticket->wait);
5053 if (ticket->bytes != ticket->orig_bytes)
5060 * This is for normal flushers, we can wait all goddamned day if we want to. We
5061 * will loop and continuously try to flush as long as we are making progress.
5062 * We count progress as clearing off tickets each time we have to loop.
5064 static void btrfs_async_reclaim_metadata_space(struct work_struct *work)
5066 struct btrfs_fs_info *fs_info;
5067 struct btrfs_space_info *space_info;
5070 int commit_cycles = 0;
5071 u64 last_tickets_id;
5073 fs_info = container_of(work, struct btrfs_fs_info, async_reclaim_work);
5074 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
5076 spin_lock(&space_info->lock);
5077 to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info,
5080 space_info->flush = 0;
5081 spin_unlock(&space_info->lock);
5084 last_tickets_id = space_info->tickets_id;
5085 spin_unlock(&space_info->lock);
5087 flush_state = FLUSH_DELAYED_ITEMS_NR;
5089 flush_space(fs_info, space_info, to_reclaim, flush_state);
5090 spin_lock(&space_info->lock);
5091 if (list_empty(&space_info->tickets)) {
5092 space_info->flush = 0;
5093 spin_unlock(&space_info->lock);
5096 to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info,
5099 if (last_tickets_id == space_info->tickets_id) {
5102 last_tickets_id = space_info->tickets_id;
5103 flush_state = FLUSH_DELAYED_ITEMS_NR;
5109 * We don't want to force a chunk allocation until we've tried
5110 * pretty hard to reclaim space. Think of the case where we
5111 * freed up a bunch of space and so have a lot of pinned space
5112 * to reclaim. We would rather use that than possibly create a
5113 * underutilized metadata chunk. So if this is our first run
5114 * through the flushing state machine skip ALLOC_CHUNK_FORCE and
5115 * commit the transaction. If nothing has changed the next go
5116 * around then we can force a chunk allocation.
5118 if (flush_state == ALLOC_CHUNK_FORCE && !commit_cycles)
5121 if (flush_state > COMMIT_TRANS) {
5123 if (commit_cycles > 2) {
5124 if (wake_all_tickets(&space_info->tickets)) {
5125 flush_state = FLUSH_DELAYED_ITEMS_NR;
5128 space_info->flush = 0;
5131 flush_state = FLUSH_DELAYED_ITEMS_NR;
5134 spin_unlock(&space_info->lock);
5135 } while (flush_state <= COMMIT_TRANS);
5138 void btrfs_init_async_reclaim_work(struct work_struct *work)
5140 INIT_WORK(work, btrfs_async_reclaim_metadata_space);
5143 static const enum btrfs_flush_state priority_flush_states[] = {
5144 FLUSH_DELAYED_ITEMS_NR,
5145 FLUSH_DELAYED_ITEMS,
5149 static void priority_reclaim_metadata_space(struct btrfs_fs_info *fs_info,
5150 struct btrfs_space_info *space_info,
5151 struct reserve_ticket *ticket)
5156 spin_lock(&space_info->lock);
5157 to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info,
5160 spin_unlock(&space_info->lock);
5163 spin_unlock(&space_info->lock);
5167 flush_space(fs_info, space_info, to_reclaim,
5168 priority_flush_states[flush_state]);
5170 spin_lock(&space_info->lock);
5171 if (ticket->bytes == 0) {
5172 spin_unlock(&space_info->lock);
5175 spin_unlock(&space_info->lock);
5176 } while (flush_state < ARRAY_SIZE(priority_flush_states));
5179 static int wait_reserve_ticket(struct btrfs_fs_info *fs_info,
5180 struct btrfs_space_info *space_info,
5181 struct reserve_ticket *ticket)
5185 u64 reclaim_bytes = 0;
5188 spin_lock(&space_info->lock);
5189 while (ticket->bytes > 0 && ticket->error == 0) {
5190 ret = prepare_to_wait_event(&ticket->wait, &wait, TASK_KILLABLE);
5195 spin_unlock(&space_info->lock);
5199 finish_wait(&ticket->wait, &wait);
5200 spin_lock(&space_info->lock);
5203 ret = ticket->error;
5204 if (!list_empty(&ticket->list))
5205 list_del_init(&ticket->list);
5206 if (ticket->bytes && ticket->bytes < ticket->orig_bytes)
5207 reclaim_bytes = ticket->orig_bytes - ticket->bytes;
5208 spin_unlock(&space_info->lock);
5211 space_info_add_old_bytes(fs_info, space_info, reclaim_bytes);
5216 * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
5217 * @root - the root we're allocating for
5218 * @space_info - the space info we want to allocate from
5219 * @orig_bytes - the number of bytes we want
5220 * @flush - whether or not we can flush to make our reservation
5222 * This will reserve orig_bytes number of bytes from the space info associated
5223 * with the block_rsv. If there is not enough space it will make an attempt to
5224 * flush out space to make room. It will do this by flushing delalloc if
5225 * possible or committing the transaction. If flush is 0 then no attempts to
5226 * regain reservations will be made and this will fail if there is not enough
5229 static int __reserve_metadata_bytes(struct btrfs_fs_info *fs_info,
5230 struct btrfs_space_info *space_info,
5232 enum btrfs_reserve_flush_enum flush,
5235 struct reserve_ticket ticket;
5237 u64 reclaim_bytes = 0;
5241 ASSERT(!current->journal_info || flush != BTRFS_RESERVE_FLUSH_ALL);
5243 spin_lock(&space_info->lock);
5245 used = btrfs_space_info_used(space_info, true);
5248 * If we have enough space then hooray, make our reservation and carry
5249 * on. If not see if we can overcommit, and if we can, hooray carry on.
5250 * If not things get more complicated.
5252 if (used + orig_bytes <= space_info->total_bytes) {
5253 update_bytes_may_use(space_info, orig_bytes);
5254 trace_btrfs_space_reservation(fs_info, "space_info",
5255 space_info->flags, orig_bytes, 1);
5257 } else if (can_overcommit(fs_info, space_info, orig_bytes, flush,
5259 update_bytes_may_use(space_info, orig_bytes);
5260 trace_btrfs_space_reservation(fs_info, "space_info",
5261 space_info->flags, orig_bytes, 1);
5266 * If we couldn't make a reservation then setup our reservation ticket
5267 * and kick the async worker if it's not already running.
5269 * If we are a priority flusher then we just need to add our ticket to
5270 * the list and we will do our own flushing further down.
5272 if (ret && flush != BTRFS_RESERVE_NO_FLUSH) {
5273 ticket.orig_bytes = orig_bytes;
5274 ticket.bytes = orig_bytes;
5276 init_waitqueue_head(&ticket.wait);
5277 if (flush == BTRFS_RESERVE_FLUSH_ALL) {
5278 list_add_tail(&ticket.list, &space_info->tickets);
5279 if (!space_info->flush) {
5280 space_info->flush = 1;
5281 trace_btrfs_trigger_flush(fs_info,
5285 queue_work(system_unbound_wq,
5286 &fs_info->async_reclaim_work);
5289 list_add_tail(&ticket.list,
5290 &space_info->priority_tickets);
5292 } else if (!ret && space_info->flags & BTRFS_BLOCK_GROUP_METADATA) {
5295 * We will do the space reservation dance during log replay,
5296 * which means we won't have fs_info->fs_root set, so don't do
5297 * the async reclaim as we will panic.
5299 if (!test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags) &&
5300 need_do_async_reclaim(fs_info, space_info,
5301 used, system_chunk) &&
5302 !work_busy(&fs_info->async_reclaim_work)) {
5303 trace_btrfs_trigger_flush(fs_info, space_info->flags,
5304 orig_bytes, flush, "preempt");
5305 queue_work(system_unbound_wq,
5306 &fs_info->async_reclaim_work);
5309 spin_unlock(&space_info->lock);
5310 if (!ret || flush == BTRFS_RESERVE_NO_FLUSH)
5313 if (flush == BTRFS_RESERVE_FLUSH_ALL)
5314 return wait_reserve_ticket(fs_info, space_info, &ticket);
5317 priority_reclaim_metadata_space(fs_info, space_info, &ticket);
5318 spin_lock(&space_info->lock);
5320 if (ticket.bytes < orig_bytes)
5321 reclaim_bytes = orig_bytes - ticket.bytes;
5322 list_del_init(&ticket.list);
5325 spin_unlock(&space_info->lock);
5328 space_info_add_old_bytes(fs_info, space_info, reclaim_bytes);
5329 ASSERT(list_empty(&ticket.list));
5334 * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
5335 * @root - the root we're allocating for
5336 * @block_rsv - the block_rsv we're allocating for
5337 * @orig_bytes - the number of bytes we want
5338 * @flush - whether or not we can flush to make our reservation
5340 * This will reserve orig_bytes number of bytes from the space info associated
5341 * with the block_rsv. If there is not enough space it will make an attempt to
5342 * flush out space to make room. It will do this by flushing delalloc if
5343 * possible or committing the transaction. If flush is 0 then no attempts to
5344 * regain reservations will be made and this will fail if there is not enough
5347 static int reserve_metadata_bytes(struct btrfs_root *root,
5348 struct btrfs_block_rsv *block_rsv,
5350 enum btrfs_reserve_flush_enum flush)
5352 struct btrfs_fs_info *fs_info = root->fs_info;
5353 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
5355 bool system_chunk = (root == fs_info->chunk_root);
5357 ret = __reserve_metadata_bytes(fs_info, block_rsv->space_info,
5358 orig_bytes, flush, system_chunk);
5359 if (ret == -ENOSPC &&
5360 unlikely(root->orphan_cleanup_state == ORPHAN_CLEANUP_STARTED)) {
5361 if (block_rsv != global_rsv &&
5362 !block_rsv_use_bytes(global_rsv, orig_bytes))
5365 if (ret == -ENOSPC) {
5366 trace_btrfs_space_reservation(fs_info, "space_info:enospc",
5367 block_rsv->space_info->flags,
5370 if (btrfs_test_opt(fs_info, ENOSPC_DEBUG))
5371 dump_space_info(fs_info, block_rsv->space_info,
5377 static struct btrfs_block_rsv *get_block_rsv(
5378 const struct btrfs_trans_handle *trans,
5379 const struct btrfs_root *root)
5381 struct btrfs_fs_info *fs_info = root->fs_info;
5382 struct btrfs_block_rsv *block_rsv = NULL;
5384 if (test_bit(BTRFS_ROOT_REF_COWS, &root->state) ||
5385 (root == fs_info->csum_root && trans->adding_csums) ||
5386 (root == fs_info->uuid_root))
5387 block_rsv = trans->block_rsv;
5390 block_rsv = root->block_rsv;
5393 block_rsv = &fs_info->empty_block_rsv;
5398 static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
5402 spin_lock(&block_rsv->lock);
5403 if (block_rsv->reserved >= num_bytes) {
5404 block_rsv->reserved -= num_bytes;
5405 if (block_rsv->reserved < block_rsv->size)
5406 block_rsv->full = 0;
5409 spin_unlock(&block_rsv->lock);
5413 static void block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
5414 u64 num_bytes, bool update_size)
5416 spin_lock(&block_rsv->lock);
5417 block_rsv->reserved += num_bytes;
5419 block_rsv->size += num_bytes;
5420 else if (block_rsv->reserved >= block_rsv->size)
5421 block_rsv->full = 1;
5422 spin_unlock(&block_rsv->lock);
5425 int btrfs_cond_migrate_bytes(struct btrfs_fs_info *fs_info,
5426 struct btrfs_block_rsv *dest, u64 num_bytes,
5429 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
5432 if (global_rsv->space_info != dest->space_info)
5435 spin_lock(&global_rsv->lock);
5436 min_bytes = div_factor(global_rsv->size, min_factor);
5437 if (global_rsv->reserved < min_bytes + num_bytes) {
5438 spin_unlock(&global_rsv->lock);
5441 global_rsv->reserved -= num_bytes;
5442 if (global_rsv->reserved < global_rsv->size)
5443 global_rsv->full = 0;
5444 spin_unlock(&global_rsv->lock);
5446 block_rsv_add_bytes(dest, num_bytes, true);
5451 * btrfs_migrate_to_delayed_refs_rsv - transfer bytes to our delayed refs rsv.
5452 * @fs_info - the fs info for our fs.
5453 * @src - the source block rsv to transfer from.
5454 * @num_bytes - the number of bytes to transfer.
5456 * This transfers up to the num_bytes amount from the src rsv to the
5457 * delayed_refs_rsv. Any extra bytes are returned to the space info.
5459 void btrfs_migrate_to_delayed_refs_rsv(struct btrfs_fs_info *fs_info,
5460 struct btrfs_block_rsv *src,
5463 struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
5466 spin_lock(&src->lock);
5467 src->reserved -= num_bytes;
5468 src->size -= num_bytes;
5469 spin_unlock(&src->lock);
5471 spin_lock(&delayed_refs_rsv->lock);
5472 if (delayed_refs_rsv->size > delayed_refs_rsv->reserved) {
5473 u64 delta = delayed_refs_rsv->size -
5474 delayed_refs_rsv->reserved;
5475 if (num_bytes > delta) {
5476 to_free = num_bytes - delta;
5480 to_free = num_bytes;
5485 delayed_refs_rsv->reserved += num_bytes;
5486 if (delayed_refs_rsv->reserved >= delayed_refs_rsv->size)
5487 delayed_refs_rsv->full = 1;
5488 spin_unlock(&delayed_refs_rsv->lock);
5491 trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv",
5494 space_info_add_old_bytes(fs_info, delayed_refs_rsv->space_info,
5499 * btrfs_delayed_refs_rsv_refill - refill based on our delayed refs usage.
5500 * @fs_info - the fs_info for our fs.
5501 * @flush - control how we can flush for this reservation.
5503 * This will refill the delayed block_rsv up to 1 items size worth of space and
5504 * will return -ENOSPC if we can't make the reservation.
5506 int btrfs_delayed_refs_rsv_refill(struct btrfs_fs_info *fs_info,
5507 enum btrfs_reserve_flush_enum flush)
5509 struct btrfs_block_rsv *block_rsv = &fs_info->delayed_refs_rsv;
5510 u64 limit = btrfs_calc_trans_metadata_size(fs_info, 1);
5514 spin_lock(&block_rsv->lock);
5515 if (block_rsv->reserved < block_rsv->size) {
5516 num_bytes = block_rsv->size - block_rsv->reserved;
5517 num_bytes = min(num_bytes, limit);
5519 spin_unlock(&block_rsv->lock);
5524 ret = reserve_metadata_bytes(fs_info->extent_root, block_rsv,
5528 block_rsv_add_bytes(block_rsv, num_bytes, 0);
5529 trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv",
5535 * This is for space we already have accounted in space_info->bytes_may_use, so
5536 * basically when we're returning space from block_rsv's.
5538 static void space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
5539 struct btrfs_space_info *space_info,
5542 struct reserve_ticket *ticket;
5543 struct list_head *head;
5545 enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_NO_FLUSH;
5546 bool check_overcommit = false;
5548 spin_lock(&space_info->lock);
5549 head = &space_info->priority_tickets;
5552 * If we are over our limit then we need to check and see if we can
5553 * overcommit, and if we can't then we just need to free up our space
5554 * and not satisfy any requests.
5556 used = btrfs_space_info_used(space_info, true);
5557 if (used - num_bytes >= space_info->total_bytes)
5558 check_overcommit = true;
5560 while (!list_empty(head) && num_bytes) {
5561 ticket = list_first_entry(head, struct reserve_ticket,
5564 * We use 0 bytes because this space is already reserved, so
5565 * adding the ticket space would be a double count.
5567 if (check_overcommit &&
5568 !can_overcommit(fs_info, space_info, 0, flush, false))
5570 if (num_bytes >= ticket->bytes) {
5571 list_del_init(&ticket->list);
5572 num_bytes -= ticket->bytes;
5574 space_info->tickets_id++;
5575 wake_up(&ticket->wait);
5577 ticket->bytes -= num_bytes;
5582 if (num_bytes && head == &space_info->priority_tickets) {
5583 head = &space_info->tickets;
5584 flush = BTRFS_RESERVE_FLUSH_ALL;
5587 update_bytes_may_use(space_info, -num_bytes);
5588 trace_btrfs_space_reservation(fs_info, "space_info",
5589 space_info->flags, num_bytes, 0);
5590 spin_unlock(&space_info->lock);
5594 * This is for newly allocated space that isn't accounted in
5595 * space_info->bytes_may_use yet. So if we allocate a chunk or unpin an extent
5596 * we use this helper.
5598 static void space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
5599 struct btrfs_space_info *space_info,
5602 struct reserve_ticket *ticket;
5603 struct list_head *head = &space_info->priority_tickets;
5606 while (!list_empty(head) && num_bytes) {
5607 ticket = list_first_entry(head, struct reserve_ticket,
5609 if (num_bytes >= ticket->bytes) {
5610 trace_btrfs_space_reservation(fs_info, "space_info",
5613 list_del_init(&ticket->list);
5614 num_bytes -= ticket->bytes;
5615 update_bytes_may_use(space_info, ticket->bytes);
5617 space_info->tickets_id++;
5618 wake_up(&ticket->wait);
5620 trace_btrfs_space_reservation(fs_info, "space_info",
5623 update_bytes_may_use(space_info, num_bytes);
5624 ticket->bytes -= num_bytes;
5629 if (num_bytes && head == &space_info->priority_tickets) {
5630 head = &space_info->tickets;
5635 static u64 block_rsv_release_bytes(struct btrfs_fs_info *fs_info,
5636 struct btrfs_block_rsv *block_rsv,
5637 struct btrfs_block_rsv *dest, u64 num_bytes,
5638 u64 *qgroup_to_release_ret)
5640 struct btrfs_space_info *space_info = block_rsv->space_info;
5641 u64 qgroup_to_release = 0;
5644 spin_lock(&block_rsv->lock);
5645 if (num_bytes == (u64)-1) {
5646 num_bytes = block_rsv->size;
5647 qgroup_to_release = block_rsv->qgroup_rsv_size;
5649 block_rsv->size -= num_bytes;
5650 if (block_rsv->reserved >= block_rsv->size) {
5651 num_bytes = block_rsv->reserved - block_rsv->size;
5652 block_rsv->reserved = block_rsv->size;
5653 block_rsv->full = 1;
5657 if (block_rsv->qgroup_rsv_reserved >= block_rsv->qgroup_rsv_size) {
5658 qgroup_to_release = block_rsv->qgroup_rsv_reserved -
5659 block_rsv->qgroup_rsv_size;
5660 block_rsv->qgroup_rsv_reserved = block_rsv->qgroup_rsv_size;
5662 qgroup_to_release = 0;
5664 spin_unlock(&block_rsv->lock);
5667 if (num_bytes > 0) {
5669 spin_lock(&dest->lock);
5673 bytes_to_add = dest->size - dest->reserved;
5674 bytes_to_add = min(num_bytes, bytes_to_add);
5675 dest->reserved += bytes_to_add;
5676 if (dest->reserved >= dest->size)
5678 num_bytes -= bytes_to_add;
5680 spin_unlock(&dest->lock);
5683 space_info_add_old_bytes(fs_info, space_info,
5686 if (qgroup_to_release_ret)
5687 *qgroup_to_release_ret = qgroup_to_release;
5691 int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src,
5692 struct btrfs_block_rsv *dst, u64 num_bytes,
5697 ret = block_rsv_use_bytes(src, num_bytes);
5701 block_rsv_add_bytes(dst, num_bytes, update_size);
5705 void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv, unsigned short type)
5707 memset(rsv, 0, sizeof(*rsv));
5708 spin_lock_init(&rsv->lock);
5712 void btrfs_init_metadata_block_rsv(struct btrfs_fs_info *fs_info,
5713 struct btrfs_block_rsv *rsv,
5714 unsigned short type)
5716 btrfs_init_block_rsv(rsv, type);
5717 rsv->space_info = __find_space_info(fs_info,
5718 BTRFS_BLOCK_GROUP_METADATA);
5721 struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_fs_info *fs_info,
5722 unsigned short type)
5724 struct btrfs_block_rsv *block_rsv;
5726 block_rsv = kmalloc(sizeof(*block_rsv), GFP_NOFS);
5730 btrfs_init_metadata_block_rsv(fs_info, block_rsv, type);
5734 void btrfs_free_block_rsv(struct btrfs_fs_info *fs_info,
5735 struct btrfs_block_rsv *rsv)
5739 btrfs_block_rsv_release(fs_info, rsv, (u64)-1);
5743 int btrfs_block_rsv_add(struct btrfs_root *root,
5744 struct btrfs_block_rsv *block_rsv, u64 num_bytes,
5745 enum btrfs_reserve_flush_enum flush)
5752 ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
5754 block_rsv_add_bytes(block_rsv, num_bytes, true);
5759 int btrfs_block_rsv_check(struct btrfs_block_rsv *block_rsv, int min_factor)
5767 spin_lock(&block_rsv->lock);
5768 num_bytes = div_factor(block_rsv->size, min_factor);
5769 if (block_rsv->reserved >= num_bytes)
5771 spin_unlock(&block_rsv->lock);
5776 int btrfs_block_rsv_refill(struct btrfs_root *root,
5777 struct btrfs_block_rsv *block_rsv, u64 min_reserved,
5778 enum btrfs_reserve_flush_enum flush)
5786 spin_lock(&block_rsv->lock);
5787 num_bytes = min_reserved;
5788 if (block_rsv->reserved >= num_bytes)
5791 num_bytes -= block_rsv->reserved;
5792 spin_unlock(&block_rsv->lock);
5797 ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
5799 block_rsv_add_bytes(block_rsv, num_bytes, false);
5806 static void calc_refill_bytes(struct btrfs_block_rsv *block_rsv,
5807 u64 *metadata_bytes, u64 *qgroup_bytes)
5809 *metadata_bytes = 0;
5812 spin_lock(&block_rsv->lock);
5813 if (block_rsv->reserved < block_rsv->size)
5814 *metadata_bytes = block_rsv->size - block_rsv->reserved;
5815 if (block_rsv->qgroup_rsv_reserved < block_rsv->qgroup_rsv_size)
5816 *qgroup_bytes = block_rsv->qgroup_rsv_size -
5817 block_rsv->qgroup_rsv_reserved;
5818 spin_unlock(&block_rsv->lock);
5822 * btrfs_inode_rsv_refill - refill the inode block rsv.
5823 * @inode - the inode we are refilling.
5824 * @flush - the flushing restriction.
5826 * Essentially the same as btrfs_block_rsv_refill, except it uses the
5827 * block_rsv->size as the minimum size. We'll either refill the missing amount
5828 * or return if we already have enough space. This will also handle the reserve
5829 * tracepoint for the reserved amount.
5831 static int btrfs_inode_rsv_refill(struct btrfs_inode *inode,
5832 enum btrfs_reserve_flush_enum flush)
5834 struct btrfs_root *root = inode->root;
5835 struct btrfs_block_rsv *block_rsv = &inode->block_rsv;
5836 u64 num_bytes, last = 0;
5837 u64 qgroup_num_bytes;
5840 calc_refill_bytes(block_rsv, &num_bytes, &qgroup_num_bytes);
5845 ret = btrfs_qgroup_reserve_meta_prealloc(root, qgroup_num_bytes,
5849 ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
5851 btrfs_qgroup_free_meta_prealloc(root, qgroup_num_bytes);
5854 * If we are fragmented we can end up with a lot of
5855 * outstanding extents which will make our size be much
5856 * larger than our reserved amount.
5858 * If the reservation happens here, it might be very
5859 * big though not needed in the end, if the delalloc
5862 * If this is the case try and do the reserve again.
5864 if (flush == BTRFS_RESERVE_FLUSH_ALL)
5865 calc_refill_bytes(block_rsv, &num_bytes,
5870 } while (ret && last != num_bytes);
5873 block_rsv_add_bytes(block_rsv, num_bytes, false);
5874 trace_btrfs_space_reservation(root->fs_info, "delalloc",
5875 btrfs_ino(inode), num_bytes, 1);
5877 /* Don't forget to increase qgroup_rsv_reserved */
5878 spin_lock(&block_rsv->lock);
5879 block_rsv->qgroup_rsv_reserved += qgroup_num_bytes;
5880 spin_unlock(&block_rsv->lock);
5885 static u64 __btrfs_block_rsv_release(struct btrfs_fs_info *fs_info,
5886 struct btrfs_block_rsv *block_rsv,
5887 u64 num_bytes, u64 *qgroup_to_release)
5889 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
5890 struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_refs_rsv;
5891 struct btrfs_block_rsv *target = delayed_rsv;
5893 if (target->full || target == block_rsv)
5894 target = global_rsv;
5896 if (block_rsv->space_info != target->space_info)
5899 return block_rsv_release_bytes(fs_info, block_rsv, target, num_bytes,
5903 void btrfs_block_rsv_release(struct btrfs_fs_info *fs_info,
5904 struct btrfs_block_rsv *block_rsv,
5907 __btrfs_block_rsv_release(fs_info, block_rsv, num_bytes, NULL);
5911 * btrfs_inode_rsv_release - release any excessive reservation.
5912 * @inode - the inode we need to release from.
5913 * @qgroup_free - free or convert qgroup meta.
5914 * Unlike normal operation, qgroup meta reservation needs to know if we are
5915 * freeing qgroup reservation or just converting it into per-trans. Normally
5916 * @qgroup_free is true for error handling, and false for normal release.
5918 * This is the same as btrfs_block_rsv_release, except that it handles the
5919 * tracepoint for the reservation.
5921 static void btrfs_inode_rsv_release(struct btrfs_inode *inode, bool qgroup_free)
5923 struct btrfs_fs_info *fs_info = inode->root->fs_info;
5924 struct btrfs_block_rsv *block_rsv = &inode->block_rsv;
5926 u64 qgroup_to_release = 0;
5929 * Since we statically set the block_rsv->size we just want to say we
5930 * are releasing 0 bytes, and then we'll just get the reservation over
5933 released = __btrfs_block_rsv_release(fs_info, block_rsv, 0,
5934 &qgroup_to_release);
5936 trace_btrfs_space_reservation(fs_info, "delalloc",
5937 btrfs_ino(inode), released, 0);
5939 btrfs_qgroup_free_meta_prealloc(inode->root, qgroup_to_release);
5941 btrfs_qgroup_convert_reserved_meta(inode->root,
5946 * btrfs_delayed_refs_rsv_release - release a ref head's reservation.
5947 * @fs_info - the fs_info for our fs.
5948 * @nr - the number of items to drop.
5950 * This drops the delayed ref head's count from the delayed refs rsv and frees
5951 * any excess reservation we had.
5953 void btrfs_delayed_refs_rsv_release(struct btrfs_fs_info *fs_info, int nr)
5955 struct btrfs_block_rsv *block_rsv = &fs_info->delayed_refs_rsv;
5956 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
5957 u64 num_bytes = btrfs_calc_trans_metadata_size(fs_info, nr);
5960 released = block_rsv_release_bytes(fs_info, block_rsv, global_rsv,
5963 trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv",
5967 static void update_global_block_rsv(struct btrfs_fs_info *fs_info)
5969 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
5970 struct btrfs_space_info *sinfo = block_rsv->space_info;
5974 * The global block rsv is based on the size of the extent tree, the
5975 * checksum tree and the root tree. If the fs is empty we want to set
5976 * it to a minimal amount for safety.
5978 num_bytes = btrfs_root_used(&fs_info->extent_root->root_item) +
5979 btrfs_root_used(&fs_info->csum_root->root_item) +
5980 btrfs_root_used(&fs_info->tree_root->root_item);
5981 num_bytes = max_t(u64, num_bytes, SZ_16M);
5983 spin_lock(&sinfo->lock);
5984 spin_lock(&block_rsv->lock);
5986 block_rsv->size = min_t(u64, num_bytes, SZ_512M);
5988 if (block_rsv->reserved < block_rsv->size) {
5989 num_bytes = btrfs_space_info_used(sinfo, true);
5990 if (sinfo->total_bytes > num_bytes) {
5991 num_bytes = sinfo->total_bytes - num_bytes;
5992 num_bytes = min(num_bytes,
5993 block_rsv->size - block_rsv->reserved);
5994 block_rsv->reserved += num_bytes;
5995 update_bytes_may_use(sinfo, num_bytes);
5996 trace_btrfs_space_reservation(fs_info, "space_info",
5997 sinfo->flags, num_bytes,
6000 } else if (block_rsv->reserved > block_rsv->size) {
6001 num_bytes = block_rsv->reserved - block_rsv->size;
6002 update_bytes_may_use(sinfo, -num_bytes);
6003 trace_btrfs_space_reservation(fs_info, "space_info",
6004 sinfo->flags, num_bytes, 0);
6005 block_rsv->reserved = block_rsv->size;
6008 if (block_rsv->reserved == block_rsv->size)
6009 block_rsv->full = 1;
6011 block_rsv->full = 0;
6013 spin_unlock(&block_rsv->lock);
6014 spin_unlock(&sinfo->lock);
6017 static void init_global_block_rsv(struct btrfs_fs_info *fs_info)
6019 struct btrfs_space_info *space_info;
6021 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
6022 fs_info->chunk_block_rsv.space_info = space_info;
6024 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
6025 fs_info->global_block_rsv.space_info = space_info;
6026 fs_info->trans_block_rsv.space_info = space_info;
6027 fs_info->empty_block_rsv.space_info = space_info;
6028 fs_info->delayed_block_rsv.space_info = space_info;
6029 fs_info->delayed_refs_rsv.space_info = space_info;
6031 fs_info->extent_root->block_rsv = &fs_info->delayed_refs_rsv;
6032 fs_info->csum_root->block_rsv = &fs_info->delayed_refs_rsv;
6033 fs_info->dev_root->block_rsv = &fs_info->global_block_rsv;
6034 fs_info->tree_root->block_rsv = &fs_info->global_block_rsv;
6035 if (fs_info->quota_root)
6036 fs_info->quota_root->block_rsv = &fs_info->global_block_rsv;
6037 fs_info->chunk_root->block_rsv = &fs_info->chunk_block_rsv;
6039 update_global_block_rsv(fs_info);
6042 static void release_global_block_rsv(struct btrfs_fs_info *fs_info)
6044 block_rsv_release_bytes(fs_info, &fs_info->global_block_rsv, NULL,
6046 WARN_ON(fs_info->trans_block_rsv.size > 0);
6047 WARN_ON(fs_info->trans_block_rsv.reserved > 0);
6048 WARN_ON(fs_info->chunk_block_rsv.size > 0);
6049 WARN_ON(fs_info->chunk_block_rsv.reserved > 0);
6050 WARN_ON(fs_info->delayed_block_rsv.size > 0);
6051 WARN_ON(fs_info->delayed_block_rsv.reserved > 0);
6052 WARN_ON(fs_info->delayed_refs_rsv.reserved > 0);
6053 WARN_ON(fs_info->delayed_refs_rsv.size > 0);
6057 * btrfs_update_delayed_refs_rsv - adjust the size of the delayed refs rsv
6058 * @trans - the trans that may have generated delayed refs
6060 * This is to be called anytime we may have adjusted trans->delayed_ref_updates,
6061 * it'll calculate the additional size and add it to the delayed_refs_rsv.
6063 void btrfs_update_delayed_refs_rsv(struct btrfs_trans_handle *trans)
6065 struct btrfs_fs_info *fs_info = trans->fs_info;
6066 struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_refs_rsv;
6069 if (!trans->delayed_ref_updates)
6072 num_bytes = btrfs_calc_trans_metadata_size(fs_info,
6073 trans->delayed_ref_updates);
6074 spin_lock(&delayed_rsv->lock);
6075 delayed_rsv->size += num_bytes;
6076 delayed_rsv->full = 0;
6077 spin_unlock(&delayed_rsv->lock);
6078 trans->delayed_ref_updates = 0;
6082 * To be called after all the new block groups attached to the transaction
6083 * handle have been created (btrfs_create_pending_block_groups()).
6085 void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans)
6087 struct btrfs_fs_info *fs_info = trans->fs_info;
6089 if (!trans->chunk_bytes_reserved)
6092 WARN_ON_ONCE(!list_empty(&trans->new_bgs));
6094 block_rsv_release_bytes(fs_info, &fs_info->chunk_block_rsv, NULL,
6095 trans->chunk_bytes_reserved, NULL);
6096 trans->chunk_bytes_reserved = 0;
6100 * btrfs_subvolume_reserve_metadata() - reserve space for subvolume operation
6101 * root: the root of the parent directory
6102 * rsv: block reservation
6103 * items: the number of items that we need do reservation
6104 * use_global_rsv: allow fallback to the global block reservation
6106 * This function is used to reserve the space for snapshot/subvolume
6107 * creation and deletion. Those operations are different with the
6108 * common file/directory operations, they change two fs/file trees
6109 * and root tree, the number of items that the qgroup reserves is
6110 * different with the free space reservation. So we can not use
6111 * the space reservation mechanism in start_transaction().
6113 int btrfs_subvolume_reserve_metadata(struct btrfs_root *root,
6114 struct btrfs_block_rsv *rsv, int items,
6115 bool use_global_rsv)
6117 u64 qgroup_num_bytes = 0;
6120 struct btrfs_fs_info *fs_info = root->fs_info;
6121 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
6123 if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)) {
6124 /* One for parent inode, two for dir entries */
6125 qgroup_num_bytes = 3 * fs_info->nodesize;
6126 ret = btrfs_qgroup_reserve_meta_prealloc(root,
6127 qgroup_num_bytes, true);
6132 num_bytes = btrfs_calc_trans_metadata_size(fs_info, items);
6133 rsv->space_info = __find_space_info(fs_info,
6134 BTRFS_BLOCK_GROUP_METADATA);
6135 ret = btrfs_block_rsv_add(root, rsv, num_bytes,
6136 BTRFS_RESERVE_FLUSH_ALL);
6138 if (ret == -ENOSPC && use_global_rsv)
6139 ret = btrfs_block_rsv_migrate(global_rsv, rsv, num_bytes, true);
6141 if (ret && qgroup_num_bytes)
6142 btrfs_qgroup_free_meta_prealloc(root, qgroup_num_bytes);
6147 void btrfs_subvolume_release_metadata(struct btrfs_fs_info *fs_info,
6148 struct btrfs_block_rsv *rsv)
6150 btrfs_block_rsv_release(fs_info, rsv, (u64)-1);
6153 static void btrfs_calculate_inode_block_rsv_size(struct btrfs_fs_info *fs_info,
6154 struct btrfs_inode *inode)
6156 struct btrfs_block_rsv *block_rsv = &inode->block_rsv;
6157 u64 reserve_size = 0;
6158 u64 qgroup_rsv_size = 0;
6160 unsigned outstanding_extents;
6162 lockdep_assert_held(&inode->lock);
6163 outstanding_extents = inode->outstanding_extents;
6164 if (outstanding_extents)
6165 reserve_size = btrfs_calc_trans_metadata_size(fs_info,
6166 outstanding_extents + 1);
6167 csum_leaves = btrfs_csum_bytes_to_leaves(fs_info,
6169 reserve_size += btrfs_calc_trans_metadata_size(fs_info,
6172 * For qgroup rsv, the calculation is very simple:
6173 * account one nodesize for each outstanding extent
6175 * This is overestimating in most cases.
6177 qgroup_rsv_size = (u64)outstanding_extents * fs_info->nodesize;
6179 spin_lock(&block_rsv->lock);
6180 block_rsv->size = reserve_size;
6181 block_rsv->qgroup_rsv_size = qgroup_rsv_size;
6182 spin_unlock(&block_rsv->lock);
6185 int btrfs_delalloc_reserve_metadata(struct btrfs_inode *inode, u64 num_bytes)
6187 struct btrfs_fs_info *fs_info = inode->root->fs_info;
6188 unsigned nr_extents;
6189 enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_FLUSH_ALL;
6191 bool delalloc_lock = true;
6193 /* If we are a free space inode we need to not flush since we will be in
6194 * the middle of a transaction commit. We also don't need the delalloc
6195 * mutex since we won't race with anybody. We need this mostly to make
6196 * lockdep shut its filthy mouth.
6198 * If we have a transaction open (can happen if we call truncate_block
6199 * from truncate), then we need FLUSH_LIMIT so we don't deadlock.
6201 if (btrfs_is_free_space_inode(inode)) {
6202 flush = BTRFS_RESERVE_NO_FLUSH;
6203 delalloc_lock = false;
6205 if (current->journal_info)
6206 flush = BTRFS_RESERVE_FLUSH_LIMIT;
6208 if (btrfs_transaction_in_commit(fs_info))
6209 schedule_timeout(1);
6213 mutex_lock(&inode->delalloc_mutex);
6215 num_bytes = ALIGN(num_bytes, fs_info->sectorsize);
6217 /* Add our new extents and calculate the new rsv size. */
6218 spin_lock(&inode->lock);
6219 nr_extents = count_max_extents(num_bytes);
6220 btrfs_mod_outstanding_extents(inode, nr_extents);
6221 inode->csum_bytes += num_bytes;
6222 btrfs_calculate_inode_block_rsv_size(fs_info, inode);
6223 spin_unlock(&inode->lock);
6225 ret = btrfs_inode_rsv_refill(inode, flush);
6230 mutex_unlock(&inode->delalloc_mutex);
6234 spin_lock(&inode->lock);
6235 nr_extents = count_max_extents(num_bytes);
6236 btrfs_mod_outstanding_extents(inode, -nr_extents);
6237 inode->csum_bytes -= num_bytes;
6238 btrfs_calculate_inode_block_rsv_size(fs_info, inode);
6239 spin_unlock(&inode->lock);
6241 btrfs_inode_rsv_release(inode, true);
6243 mutex_unlock(&inode->delalloc_mutex);
6248 * btrfs_delalloc_release_metadata - release a metadata reservation for an inode
6249 * @inode: the inode to release the reservation for.
6250 * @num_bytes: the number of bytes we are releasing.
6251 * @qgroup_free: free qgroup reservation or convert it to per-trans reservation
6253 * This will release the metadata reservation for an inode. This can be called
6254 * once we complete IO for a given set of bytes to release their metadata
6255 * reservations, or on error for the same reason.
6257 void btrfs_delalloc_release_metadata(struct btrfs_inode *inode, u64 num_bytes,
6260 struct btrfs_fs_info *fs_info = inode->root->fs_info;
6262 num_bytes = ALIGN(num_bytes, fs_info->sectorsize);
6263 spin_lock(&inode->lock);
6264 inode->csum_bytes -= num_bytes;
6265 btrfs_calculate_inode_block_rsv_size(fs_info, inode);
6266 spin_unlock(&inode->lock);
6268 if (btrfs_is_testing(fs_info))
6271 btrfs_inode_rsv_release(inode, qgroup_free);
6275 * btrfs_delalloc_release_extents - release our outstanding_extents
6276 * @inode: the inode to balance the reservation for.
6277 * @num_bytes: the number of bytes we originally reserved with
6278 * @qgroup_free: do we need to free qgroup meta reservation or convert them.
6280 * When we reserve space we increase outstanding_extents for the extents we may
6281 * add. Once we've set the range as delalloc or created our ordered extents we
6282 * have outstanding_extents to track the real usage, so we use this to free our
6283 * temporarily tracked outstanding_extents. This _must_ be used in conjunction
6284 * with btrfs_delalloc_reserve_metadata.
6286 void btrfs_delalloc_release_extents(struct btrfs_inode *inode, u64 num_bytes,
6289 struct btrfs_fs_info *fs_info = inode->root->fs_info;
6290 unsigned num_extents;
6292 spin_lock(&inode->lock);
6293 num_extents = count_max_extents(num_bytes);
6294 btrfs_mod_outstanding_extents(inode, -num_extents);
6295 btrfs_calculate_inode_block_rsv_size(fs_info, inode);
6296 spin_unlock(&inode->lock);
6298 if (btrfs_is_testing(fs_info))
6301 btrfs_inode_rsv_release(inode, qgroup_free);
6305 * btrfs_delalloc_reserve_space - reserve data and metadata space for
6307 * @inode: inode we're writing to
6308 * @start: start range we are writing to
6309 * @len: how long the range we are writing to
6310 * @reserved: mandatory parameter, record actually reserved qgroup ranges of
6311 * current reservation.
6313 * This will do the following things
6315 * o reserve space in data space info for num bytes
6316 * and reserve precious corresponding qgroup space
6317 * (Done in check_data_free_space)
6319 * o reserve space for metadata space, based on the number of outstanding
6320 * extents and how much csums will be needed
6321 * also reserve metadata space in a per root over-reserve method.
6322 * o add to the inodes->delalloc_bytes
6323 * o add it to the fs_info's delalloc inodes list.
6324 * (Above 3 all done in delalloc_reserve_metadata)
6326 * Return 0 for success
6327 * Return <0 for error(-ENOSPC or -EQUOT)
6329 int btrfs_delalloc_reserve_space(struct inode *inode,
6330 struct extent_changeset **reserved, u64 start, u64 len)
6334 ret = btrfs_check_data_free_space(inode, reserved, start, len);
6337 ret = btrfs_delalloc_reserve_metadata(BTRFS_I(inode), len);
6339 btrfs_free_reserved_data_space(inode, *reserved, start, len);
6344 * btrfs_delalloc_release_space - release data and metadata space for delalloc
6345 * @inode: inode we're releasing space for
6346 * @start: start position of the space already reserved
6347 * @len: the len of the space already reserved
6348 * @release_bytes: the len of the space we consumed or didn't use
6350 * This function will release the metadata space that was not used and will
6351 * decrement ->delalloc_bytes and remove it from the fs_info delalloc_inodes
6352 * list if there are no delalloc bytes left.
6353 * Also it will handle the qgroup reserved space.
6355 void btrfs_delalloc_release_space(struct inode *inode,
6356 struct extent_changeset *reserved,
6357 u64 start, u64 len, bool qgroup_free)
6359 btrfs_delalloc_release_metadata(BTRFS_I(inode), len, qgroup_free);
6360 btrfs_free_reserved_data_space(inode, reserved, start, len);
6363 static int update_block_group(struct btrfs_trans_handle *trans,
6364 struct btrfs_fs_info *info, u64 bytenr,
6365 u64 num_bytes, int alloc)
6367 struct btrfs_block_group_cache *cache = NULL;
6368 u64 total = num_bytes;
6374 /* block accounting for super block */
6375 spin_lock(&info->delalloc_root_lock);
6376 old_val = btrfs_super_bytes_used(info->super_copy);
6378 old_val += num_bytes;
6380 old_val -= num_bytes;
6381 btrfs_set_super_bytes_used(info->super_copy, old_val);
6382 spin_unlock(&info->delalloc_root_lock);
6385 cache = btrfs_lookup_block_group(info, bytenr);
6390 factor = btrfs_bg_type_to_factor(cache->flags);
6393 * If this block group has free space cache written out, we
6394 * need to make sure to load it if we are removing space. This
6395 * is because we need the unpinning stage to actually add the
6396 * space back to the block group, otherwise we will leak space.
6398 if (!alloc && cache->cached == BTRFS_CACHE_NO)
6399 cache_block_group(cache, 1);
6401 byte_in_group = bytenr - cache->key.objectid;
6402 WARN_ON(byte_in_group > cache->key.offset);
6404 spin_lock(&cache->space_info->lock);
6405 spin_lock(&cache->lock);
6407 if (btrfs_test_opt(info, SPACE_CACHE) &&
6408 cache->disk_cache_state < BTRFS_DC_CLEAR)
6409 cache->disk_cache_state = BTRFS_DC_CLEAR;
6411 old_val = btrfs_block_group_used(&cache->item);
6412 num_bytes = min(total, cache->key.offset - byte_in_group);
6414 old_val += num_bytes;
6415 btrfs_set_block_group_used(&cache->item, old_val);
6416 cache->reserved -= num_bytes;
6417 cache->space_info->bytes_reserved -= num_bytes;
6418 cache->space_info->bytes_used += num_bytes;
6419 cache->space_info->disk_used += num_bytes * factor;
6420 spin_unlock(&cache->lock);
6421 spin_unlock(&cache->space_info->lock);
6423 old_val -= num_bytes;
6424 btrfs_set_block_group_used(&cache->item, old_val);
6425 cache->pinned += num_bytes;
6426 update_bytes_pinned(cache->space_info, num_bytes);
6427 cache->space_info->bytes_used -= num_bytes;
6428 cache->space_info->disk_used -= num_bytes * factor;
6429 spin_unlock(&cache->lock);
6430 spin_unlock(&cache->space_info->lock);
6432 trace_btrfs_space_reservation(info, "pinned",
6433 cache->space_info->flags,
6435 percpu_counter_add_batch(&cache->space_info->total_bytes_pinned,
6437 BTRFS_TOTAL_BYTES_PINNED_BATCH);
6438 set_extent_dirty(info->pinned_extents,
6439 bytenr, bytenr + num_bytes - 1,
6440 GFP_NOFS | __GFP_NOFAIL);
6443 spin_lock(&trans->transaction->dirty_bgs_lock);
6444 if (list_empty(&cache->dirty_list)) {
6445 list_add_tail(&cache->dirty_list,
6446 &trans->transaction->dirty_bgs);
6447 trans->transaction->num_dirty_bgs++;
6448 trans->delayed_ref_updates++;
6449 btrfs_get_block_group(cache);
6451 spin_unlock(&trans->transaction->dirty_bgs_lock);
6454 * No longer have used bytes in this block group, queue it for
6455 * deletion. We do this after adding the block group to the
6456 * dirty list to avoid races between cleaner kthread and space
6459 if (!alloc && old_val == 0)
6460 btrfs_mark_bg_unused(cache);
6462 btrfs_put_block_group(cache);
6464 bytenr += num_bytes;
6467 /* Modified block groups are accounted for in the delayed_refs_rsv. */
6468 btrfs_update_delayed_refs_rsv(trans);
6472 static u64 first_logical_byte(struct btrfs_fs_info *fs_info, u64 search_start)
6474 struct btrfs_block_group_cache *cache;
6477 spin_lock(&fs_info->block_group_cache_lock);
6478 bytenr = fs_info->first_logical_byte;
6479 spin_unlock(&fs_info->block_group_cache_lock);
6481 if (bytenr < (u64)-1)
6484 cache = btrfs_lookup_first_block_group(fs_info, search_start);
6488 bytenr = cache->key.objectid;
6489 btrfs_put_block_group(cache);
6494 static int pin_down_extent(struct btrfs_fs_info *fs_info,
6495 struct btrfs_block_group_cache *cache,
6496 u64 bytenr, u64 num_bytes, int reserved)
6498 spin_lock(&cache->space_info->lock);
6499 spin_lock(&cache->lock);
6500 cache->pinned += num_bytes;
6501 update_bytes_pinned(cache->space_info, num_bytes);
6503 cache->reserved -= num_bytes;
6504 cache->space_info->bytes_reserved -= num_bytes;
6506 spin_unlock(&cache->lock);
6507 spin_unlock(&cache->space_info->lock);
6509 trace_btrfs_space_reservation(fs_info, "pinned",
6510 cache->space_info->flags, num_bytes, 1);
6511 percpu_counter_add_batch(&cache->space_info->total_bytes_pinned,
6512 num_bytes, BTRFS_TOTAL_BYTES_PINNED_BATCH);
6513 set_extent_dirty(fs_info->pinned_extents, bytenr,
6514 bytenr + num_bytes - 1, GFP_NOFS | __GFP_NOFAIL);
6519 * this function must be called within transaction
6521 int btrfs_pin_extent(struct btrfs_fs_info *fs_info,
6522 u64 bytenr, u64 num_bytes, int reserved)
6524 struct btrfs_block_group_cache *cache;
6526 cache = btrfs_lookup_block_group(fs_info, bytenr);
6527 BUG_ON(!cache); /* Logic error */
6529 pin_down_extent(fs_info, cache, bytenr, num_bytes, reserved);
6531 btrfs_put_block_group(cache);
6536 * this function must be called within transaction
6538 int btrfs_pin_extent_for_log_replay(struct btrfs_fs_info *fs_info,
6539 u64 bytenr, u64 num_bytes)
6541 struct btrfs_block_group_cache *cache;
6544 cache = btrfs_lookup_block_group(fs_info, bytenr);
6549 * pull in the free space cache (if any) so that our pin
6550 * removes the free space from the cache. We have load_only set
6551 * to one because the slow code to read in the free extents does check
6552 * the pinned extents.
6554 cache_block_group(cache, 1);
6556 pin_down_extent(fs_info, cache, bytenr, num_bytes, 0);
6558 /* remove us from the free space cache (if we're there at all) */
6559 ret = btrfs_remove_free_space(cache, bytenr, num_bytes);
6560 btrfs_put_block_group(cache);
6564 static int __exclude_logged_extent(struct btrfs_fs_info *fs_info,
6565 u64 start, u64 num_bytes)
6568 struct btrfs_block_group_cache *block_group;
6569 struct btrfs_caching_control *caching_ctl;
6571 block_group = btrfs_lookup_block_group(fs_info, start);
6575 cache_block_group(block_group, 0);
6576 caching_ctl = get_caching_control(block_group);
6580 BUG_ON(!block_group_cache_done(block_group));
6581 ret = btrfs_remove_free_space(block_group, start, num_bytes);
6583 mutex_lock(&caching_ctl->mutex);
6585 if (start >= caching_ctl->progress) {
6586 ret = add_excluded_extent(fs_info, start, num_bytes);
6587 } else if (start + num_bytes <= caching_ctl->progress) {
6588 ret = btrfs_remove_free_space(block_group,
6591 num_bytes = caching_ctl->progress - start;
6592 ret = btrfs_remove_free_space(block_group,
6597 num_bytes = (start + num_bytes) -
6598 caching_ctl->progress;
6599 start = caching_ctl->progress;
6600 ret = add_excluded_extent(fs_info, start, num_bytes);
6603 mutex_unlock(&caching_ctl->mutex);
6604 put_caching_control(caching_ctl);
6606 btrfs_put_block_group(block_group);
6610 int btrfs_exclude_logged_extents(struct btrfs_fs_info *fs_info,
6611 struct extent_buffer *eb)
6613 struct btrfs_file_extent_item *item;
6614 struct btrfs_key key;
6619 if (!btrfs_fs_incompat(fs_info, MIXED_GROUPS))
6622 for (i = 0; i < btrfs_header_nritems(eb); i++) {
6623 btrfs_item_key_to_cpu(eb, &key, i);
6624 if (key.type != BTRFS_EXTENT_DATA_KEY)
6626 item = btrfs_item_ptr(eb, i, struct btrfs_file_extent_item);
6627 found_type = btrfs_file_extent_type(eb, item);
6628 if (found_type == BTRFS_FILE_EXTENT_INLINE)
6630 if (btrfs_file_extent_disk_bytenr(eb, item) == 0)
6632 key.objectid = btrfs_file_extent_disk_bytenr(eb, item);
6633 key.offset = btrfs_file_extent_disk_num_bytes(eb, item);
6634 ret = __exclude_logged_extent(fs_info, key.objectid, key.offset);
6643 btrfs_inc_block_group_reservations(struct btrfs_block_group_cache *bg)
6645 atomic_inc(&bg->reservations);
6648 void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info,
6651 struct btrfs_block_group_cache *bg;
6653 bg = btrfs_lookup_block_group(fs_info, start);
6655 if (atomic_dec_and_test(&bg->reservations))
6656 wake_up_var(&bg->reservations);
6657 btrfs_put_block_group(bg);
6660 void btrfs_wait_block_group_reservations(struct btrfs_block_group_cache *bg)
6662 struct btrfs_space_info *space_info = bg->space_info;
6666 if (!(bg->flags & BTRFS_BLOCK_GROUP_DATA))
6670 * Our block group is read only but before we set it to read only,
6671 * some task might have had allocated an extent from it already, but it
6672 * has not yet created a respective ordered extent (and added it to a
6673 * root's list of ordered extents).
6674 * Therefore wait for any task currently allocating extents, since the
6675 * block group's reservations counter is incremented while a read lock
6676 * on the groups' semaphore is held and decremented after releasing
6677 * the read access on that semaphore and creating the ordered extent.
6679 down_write(&space_info->groups_sem);
6680 up_write(&space_info->groups_sem);
6682 wait_var_event(&bg->reservations, !atomic_read(&bg->reservations));
6686 * btrfs_add_reserved_bytes - update the block_group and space info counters
6687 * @cache: The cache we are manipulating
6688 * @ram_bytes: The number of bytes of file content, and will be same to
6689 * @num_bytes except for the compress path.
6690 * @num_bytes: The number of bytes in question
6691 * @delalloc: The blocks are allocated for the delalloc write
6693 * This is called by the allocator when it reserves space. If this is a
6694 * reservation and the block group has become read only we cannot make the
6695 * reservation and return -EAGAIN, otherwise this function always succeeds.
6697 static int btrfs_add_reserved_bytes(struct btrfs_block_group_cache *cache,
6698 u64 ram_bytes, u64 num_bytes, int delalloc)
6700 struct btrfs_space_info *space_info = cache->space_info;
6703 spin_lock(&space_info->lock);
6704 spin_lock(&cache->lock);
6708 cache->reserved += num_bytes;
6709 space_info->bytes_reserved += num_bytes;
6710 update_bytes_may_use(space_info, -ram_bytes);
6712 cache->delalloc_bytes += num_bytes;
6714 spin_unlock(&cache->lock);
6715 spin_unlock(&space_info->lock);
6720 * btrfs_free_reserved_bytes - update the block_group and space info counters
6721 * @cache: The cache we are manipulating
6722 * @num_bytes: The number of bytes in question
6723 * @delalloc: The blocks are allocated for the delalloc write
6725 * This is called by somebody who is freeing space that was never actually used
6726 * on disk. For example if you reserve some space for a new leaf in transaction
6727 * A and before transaction A commits you free that leaf, you call this with
6728 * reserve set to 0 in order to clear the reservation.
6731 static void btrfs_free_reserved_bytes(struct btrfs_block_group_cache *cache,
6732 u64 num_bytes, int delalloc)
6734 struct btrfs_space_info *space_info = cache->space_info;
6736 spin_lock(&space_info->lock);
6737 spin_lock(&cache->lock);
6739 space_info->bytes_readonly += num_bytes;
6740 cache->reserved -= num_bytes;
6741 space_info->bytes_reserved -= num_bytes;
6742 space_info->max_extent_size = 0;
6745 cache->delalloc_bytes -= num_bytes;
6746 spin_unlock(&cache->lock);
6747 spin_unlock(&space_info->lock);
6749 void btrfs_prepare_extent_commit(struct btrfs_fs_info *fs_info)
6751 struct btrfs_caching_control *next;
6752 struct btrfs_caching_control *caching_ctl;
6753 struct btrfs_block_group_cache *cache;
6755 down_write(&fs_info->commit_root_sem);
6757 list_for_each_entry_safe(caching_ctl, next,
6758 &fs_info->caching_block_groups, list) {
6759 cache = caching_ctl->block_group;
6760 if (block_group_cache_done(cache)) {
6761 cache->last_byte_to_unpin = (u64)-1;
6762 list_del_init(&caching_ctl->list);
6763 put_caching_control(caching_ctl);
6765 cache->last_byte_to_unpin = caching_ctl->progress;
6769 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
6770 fs_info->pinned_extents = &fs_info->freed_extents[1];
6772 fs_info->pinned_extents = &fs_info->freed_extents[0];
6774 up_write(&fs_info->commit_root_sem);
6776 update_global_block_rsv(fs_info);
6780 * Returns the free cluster for the given space info and sets empty_cluster to
6781 * what it should be based on the mount options.
6783 static struct btrfs_free_cluster *
6784 fetch_cluster_info(struct btrfs_fs_info *fs_info,
6785 struct btrfs_space_info *space_info, u64 *empty_cluster)
6787 struct btrfs_free_cluster *ret = NULL;
6790 if (btrfs_mixed_space_info(space_info))
6793 if (space_info->flags & BTRFS_BLOCK_GROUP_METADATA) {
6794 ret = &fs_info->meta_alloc_cluster;
6795 if (btrfs_test_opt(fs_info, SSD))
6796 *empty_cluster = SZ_2M;
6798 *empty_cluster = SZ_64K;
6799 } else if ((space_info->flags & BTRFS_BLOCK_GROUP_DATA) &&
6800 btrfs_test_opt(fs_info, SSD_SPREAD)) {
6801 *empty_cluster = SZ_2M;
6802 ret = &fs_info->data_alloc_cluster;
6808 static int unpin_extent_range(struct btrfs_fs_info *fs_info,
6810 const bool return_free_space)
6812 struct btrfs_block_group_cache *cache = NULL;
6813 struct btrfs_space_info *space_info;
6814 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
6815 struct btrfs_free_cluster *cluster = NULL;
6817 u64 total_unpinned = 0;
6818 u64 empty_cluster = 0;
6821 while (start <= end) {
6824 start >= cache->key.objectid + cache->key.offset) {
6826 btrfs_put_block_group(cache);
6828 cache = btrfs_lookup_block_group(fs_info, start);
6829 BUG_ON(!cache); /* Logic error */
6831 cluster = fetch_cluster_info(fs_info,
6834 empty_cluster <<= 1;
6837 len = cache->key.objectid + cache->key.offset - start;
6838 len = min(len, end + 1 - start);
6840 if (start < cache->last_byte_to_unpin) {
6841 len = min(len, cache->last_byte_to_unpin - start);
6842 if (return_free_space)
6843 btrfs_add_free_space(cache, start, len);
6847 total_unpinned += len;
6848 space_info = cache->space_info;
6851 * If this space cluster has been marked as fragmented and we've
6852 * unpinned enough in this block group to potentially allow a
6853 * cluster to be created inside of it go ahead and clear the
6856 if (cluster && cluster->fragmented &&
6857 total_unpinned > empty_cluster) {
6858 spin_lock(&cluster->lock);
6859 cluster->fragmented = 0;
6860 spin_unlock(&cluster->lock);
6863 spin_lock(&space_info->lock);
6864 spin_lock(&cache->lock);
6865 cache->pinned -= len;
6866 update_bytes_pinned(space_info, -len);
6868 trace_btrfs_space_reservation(fs_info, "pinned",
6869 space_info->flags, len, 0);
6870 space_info->max_extent_size = 0;
6871 percpu_counter_add_batch(&space_info->total_bytes_pinned,
6872 -len, BTRFS_TOTAL_BYTES_PINNED_BATCH);
6874 space_info->bytes_readonly += len;
6877 spin_unlock(&cache->lock);
6878 if (!readonly && return_free_space &&
6879 global_rsv->space_info == space_info) {
6882 spin_lock(&global_rsv->lock);
6883 if (!global_rsv->full) {
6884 to_add = min(len, global_rsv->size -
6885 global_rsv->reserved);
6886 global_rsv->reserved += to_add;
6887 update_bytes_may_use(space_info, to_add);
6888 if (global_rsv->reserved >= global_rsv->size)
6889 global_rsv->full = 1;
6890 trace_btrfs_space_reservation(fs_info,
6896 spin_unlock(&global_rsv->lock);
6897 /* Add to any tickets we may have */
6899 space_info_add_new_bytes(fs_info, space_info,
6902 spin_unlock(&space_info->lock);
6906 btrfs_put_block_group(cache);
6910 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans)
6912 struct btrfs_fs_info *fs_info = trans->fs_info;
6913 struct btrfs_block_group_cache *block_group, *tmp;
6914 struct list_head *deleted_bgs;
6915 struct extent_io_tree *unpin;
6920 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
6921 unpin = &fs_info->freed_extents[1];
6923 unpin = &fs_info->freed_extents[0];
6925 while (!trans->aborted) {
6926 struct extent_state *cached_state = NULL;
6928 mutex_lock(&fs_info->unused_bg_unpin_mutex);
6929 ret = find_first_extent_bit(unpin, 0, &start, &end,
6930 EXTENT_DIRTY, &cached_state);
6932 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
6936 if (btrfs_test_opt(fs_info, DISCARD))
6937 ret = btrfs_discard_extent(fs_info, start,
6938 end + 1 - start, NULL);
6940 clear_extent_dirty(unpin, start, end, &cached_state);
6941 unpin_extent_range(fs_info, start, end, true);
6942 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
6943 free_extent_state(cached_state);
6948 * Transaction is finished. We don't need the lock anymore. We
6949 * do need to clean up the block groups in case of a transaction
6952 deleted_bgs = &trans->transaction->deleted_bgs;
6953 list_for_each_entry_safe(block_group, tmp, deleted_bgs, bg_list) {
6957 if (!trans->aborted)
6958 ret = btrfs_discard_extent(fs_info,
6959 block_group->key.objectid,
6960 block_group->key.offset,
6963 list_del_init(&block_group->bg_list);
6964 btrfs_put_block_group_trimming(block_group);
6965 btrfs_put_block_group(block_group);
6968 const char *errstr = btrfs_decode_error(ret);
6970 "discard failed while removing blockgroup: errno=%d %s",
6978 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
6979 struct btrfs_delayed_ref_node *node, u64 parent,
6980 u64 root_objectid, u64 owner_objectid,
6981 u64 owner_offset, int refs_to_drop,
6982 struct btrfs_delayed_extent_op *extent_op)
6984 struct btrfs_fs_info *info = trans->fs_info;
6985 struct btrfs_key key;
6986 struct btrfs_path *path;
6987 struct btrfs_root *extent_root = info->extent_root;
6988 struct extent_buffer *leaf;
6989 struct btrfs_extent_item *ei;
6990 struct btrfs_extent_inline_ref *iref;
6993 int extent_slot = 0;
6994 int found_extent = 0;
6998 u64 bytenr = node->bytenr;
6999 u64 num_bytes = node->num_bytes;
7001 bool skinny_metadata = btrfs_fs_incompat(info, SKINNY_METADATA);
7003 path = btrfs_alloc_path();
7007 path->reada = READA_FORWARD;
7008 path->leave_spinning = 1;
7010 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
7011 BUG_ON(!is_data && refs_to_drop != 1);
7014 skinny_metadata = false;
7016 ret = lookup_extent_backref(trans, path, &iref, bytenr, num_bytes,
7017 parent, root_objectid, owner_objectid,
7020 extent_slot = path->slots[0];
7021 while (extent_slot >= 0) {
7022 btrfs_item_key_to_cpu(path->nodes[0], &key,
7024 if (key.objectid != bytenr)
7026 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
7027 key.offset == num_bytes) {
7031 if (key.type == BTRFS_METADATA_ITEM_KEY &&
7032 key.offset == owner_objectid) {
7036 if (path->slots[0] - extent_slot > 5)
7041 if (!found_extent) {
7043 ret = remove_extent_backref(trans, path, NULL,
7045 is_data, &last_ref);
7047 btrfs_abort_transaction(trans, ret);
7050 btrfs_release_path(path);
7051 path->leave_spinning = 1;
7053 key.objectid = bytenr;
7054 key.type = BTRFS_EXTENT_ITEM_KEY;
7055 key.offset = num_bytes;
7057 if (!is_data && skinny_metadata) {
7058 key.type = BTRFS_METADATA_ITEM_KEY;
7059 key.offset = owner_objectid;
7062 ret = btrfs_search_slot(trans, extent_root,
7064 if (ret > 0 && skinny_metadata && path->slots[0]) {
7066 * Couldn't find our skinny metadata item,
7067 * see if we have ye olde extent item.
7070 btrfs_item_key_to_cpu(path->nodes[0], &key,
7072 if (key.objectid == bytenr &&
7073 key.type == BTRFS_EXTENT_ITEM_KEY &&
7074 key.offset == num_bytes)
7078 if (ret > 0 && skinny_metadata) {
7079 skinny_metadata = false;
7080 key.objectid = bytenr;
7081 key.type = BTRFS_EXTENT_ITEM_KEY;
7082 key.offset = num_bytes;
7083 btrfs_release_path(path);
7084 ret = btrfs_search_slot(trans, extent_root,
7090 "umm, got %d back from search, was looking for %llu",
7093 btrfs_print_leaf(path->nodes[0]);
7096 btrfs_abort_transaction(trans, ret);
7099 extent_slot = path->slots[0];
7101 } else if (WARN_ON(ret == -ENOENT)) {
7102 btrfs_print_leaf(path->nodes[0]);
7104 "unable to find ref byte nr %llu parent %llu root %llu owner %llu offset %llu",
7105 bytenr, parent, root_objectid, owner_objectid,
7107 btrfs_abort_transaction(trans, ret);
7110 btrfs_abort_transaction(trans, ret);
7114 leaf = path->nodes[0];
7115 item_size = btrfs_item_size_nr(leaf, extent_slot);
7116 if (unlikely(item_size < sizeof(*ei))) {
7118 btrfs_print_v0_err(info);
7119 btrfs_abort_transaction(trans, ret);
7122 ei = btrfs_item_ptr(leaf, extent_slot,
7123 struct btrfs_extent_item);
7124 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID &&
7125 key.type == BTRFS_EXTENT_ITEM_KEY) {
7126 struct btrfs_tree_block_info *bi;
7127 BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
7128 bi = (struct btrfs_tree_block_info *)(ei + 1);
7129 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
7132 refs = btrfs_extent_refs(leaf, ei);
7133 if (refs < refs_to_drop) {
7135 "trying to drop %d refs but we only have %Lu for bytenr %Lu",
7136 refs_to_drop, refs, bytenr);
7138 btrfs_abort_transaction(trans, ret);
7141 refs -= refs_to_drop;
7145 __run_delayed_extent_op(extent_op, leaf, ei);
7147 * In the case of inline back ref, reference count will
7148 * be updated by remove_extent_backref
7151 BUG_ON(!found_extent);
7153 btrfs_set_extent_refs(leaf, ei, refs);
7154 btrfs_mark_buffer_dirty(leaf);
7157 ret = remove_extent_backref(trans, path, iref,
7158 refs_to_drop, is_data,
7161 btrfs_abort_transaction(trans, ret);
7167 BUG_ON(is_data && refs_to_drop !=
7168 extent_data_ref_count(path, iref));
7170 BUG_ON(path->slots[0] != extent_slot);
7172 BUG_ON(path->slots[0] != extent_slot + 1);
7173 path->slots[0] = extent_slot;
7179 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
7182 btrfs_abort_transaction(trans, ret);
7185 btrfs_release_path(path);
7188 ret = btrfs_del_csums(trans, info, bytenr, num_bytes);
7190 btrfs_abort_transaction(trans, ret);
7195 ret = add_to_free_space_tree(trans, bytenr, num_bytes);
7197 btrfs_abort_transaction(trans, ret);
7201 ret = update_block_group(trans, info, bytenr, num_bytes, 0);
7203 btrfs_abort_transaction(trans, ret);
7207 btrfs_release_path(path);
7210 btrfs_free_path(path);
7215 * when we free an block, it is possible (and likely) that we free the last
7216 * delayed ref for that extent as well. This searches the delayed ref tree for
7217 * a given extent, and if there are no other delayed refs to be processed, it
7218 * removes it from the tree.
7220 static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans,
7223 struct btrfs_delayed_ref_head *head;
7224 struct btrfs_delayed_ref_root *delayed_refs;
7227 delayed_refs = &trans->transaction->delayed_refs;
7228 spin_lock(&delayed_refs->lock);
7229 head = btrfs_find_delayed_ref_head(delayed_refs, bytenr);
7231 goto out_delayed_unlock;
7233 spin_lock(&head->lock);
7234 if (!RB_EMPTY_ROOT(&head->ref_tree.rb_root))
7237 if (cleanup_extent_op(head) != NULL)
7241 * waiting for the lock here would deadlock. If someone else has it
7242 * locked they are already in the process of dropping it anyway
7244 if (!mutex_trylock(&head->mutex))
7247 btrfs_delete_ref_head(delayed_refs, head);
7248 head->processing = 0;
7250 spin_unlock(&head->lock);
7251 spin_unlock(&delayed_refs->lock);
7253 BUG_ON(head->extent_op);
7254 if (head->must_insert_reserved)
7257 btrfs_cleanup_ref_head_accounting(trans->fs_info, delayed_refs, head);
7258 mutex_unlock(&head->mutex);
7259 btrfs_put_delayed_ref_head(head);
7262 spin_unlock(&head->lock);
7265 spin_unlock(&delayed_refs->lock);
7269 void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
7270 struct btrfs_root *root,
7271 struct extent_buffer *buf,
7272 u64 parent, int last_ref)
7274 struct btrfs_fs_info *fs_info = root->fs_info;
7278 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
7279 int old_ref_mod, new_ref_mod;
7281 btrfs_ref_tree_mod(root, buf->start, buf->len, parent,
7282 root->root_key.objectid,
7283 btrfs_header_level(buf), 0,
7284 BTRFS_DROP_DELAYED_REF);
7285 ret = btrfs_add_delayed_tree_ref(trans, buf->start,
7287 root->root_key.objectid,
7288 btrfs_header_level(buf),
7289 BTRFS_DROP_DELAYED_REF, NULL,
7290 &old_ref_mod, &new_ref_mod);
7291 BUG_ON(ret); /* -ENOMEM */
7292 pin = old_ref_mod >= 0 && new_ref_mod < 0;
7295 if (last_ref && btrfs_header_generation(buf) == trans->transid) {
7296 struct btrfs_block_group_cache *cache;
7298 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
7299 ret = check_ref_cleanup(trans, buf->start);
7305 cache = btrfs_lookup_block_group(fs_info, buf->start);
7307 if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
7308 pin_down_extent(fs_info, cache, buf->start,
7310 btrfs_put_block_group(cache);
7314 WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags));
7316 btrfs_add_free_space(cache, buf->start, buf->len);
7317 btrfs_free_reserved_bytes(cache, buf->len, 0);
7318 btrfs_put_block_group(cache);
7319 trace_btrfs_reserved_extent_free(fs_info, buf->start, buf->len);
7323 add_pinned_bytes(fs_info, buf->len, true,
7324 root->root_key.objectid);
7328 * Deleting the buffer, clear the corrupt flag since it doesn't
7331 clear_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags);
7335 /* Can return -ENOMEM */
7336 int btrfs_free_extent(struct btrfs_trans_handle *trans,
7337 struct btrfs_root *root,
7338 u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid,
7339 u64 owner, u64 offset)
7341 struct btrfs_fs_info *fs_info = root->fs_info;
7342 int old_ref_mod, new_ref_mod;
7345 if (btrfs_is_testing(fs_info))
7348 if (root_objectid != BTRFS_TREE_LOG_OBJECTID)
7349 btrfs_ref_tree_mod(root, bytenr, num_bytes, parent,
7350 root_objectid, owner, offset,
7351 BTRFS_DROP_DELAYED_REF);
7354 * tree log blocks never actually go into the extent allocation
7355 * tree, just update pinning info and exit early.
7357 if (root_objectid == BTRFS_TREE_LOG_OBJECTID) {
7358 WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID);
7359 /* unlocks the pinned mutex */
7360 btrfs_pin_extent(fs_info, bytenr, num_bytes, 1);
7361 old_ref_mod = new_ref_mod = 0;
7363 } else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
7364 ret = btrfs_add_delayed_tree_ref(trans, bytenr,
7366 root_objectid, (int)owner,
7367 BTRFS_DROP_DELAYED_REF, NULL,
7368 &old_ref_mod, &new_ref_mod);
7370 ret = btrfs_add_delayed_data_ref(trans, bytenr,
7372 root_objectid, owner, offset,
7373 0, BTRFS_DROP_DELAYED_REF,
7374 &old_ref_mod, &new_ref_mod);
7377 if (ret == 0 && old_ref_mod >= 0 && new_ref_mod < 0) {
7378 bool metadata = owner < BTRFS_FIRST_FREE_OBJECTID;
7380 add_pinned_bytes(fs_info, num_bytes, metadata, root_objectid);
7387 * when we wait for progress in the block group caching, its because
7388 * our allocation attempt failed at least once. So, we must sleep
7389 * and let some progress happen before we try again.
7391 * This function will sleep at least once waiting for new free space to
7392 * show up, and then it will check the block group free space numbers
7393 * for our min num_bytes. Another option is to have it go ahead
7394 * and look in the rbtree for a free extent of a given size, but this
7397 * Callers of this must check if cache->cached == BTRFS_CACHE_ERROR before using
7398 * any of the information in this block group.
7400 static noinline void
7401 wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
7404 struct btrfs_caching_control *caching_ctl;
7406 caching_ctl = get_caching_control(cache);
7410 wait_event(caching_ctl->wait, block_group_cache_done(cache) ||
7411 (cache->free_space_ctl->free_space >= num_bytes));
7413 put_caching_control(caching_ctl);
7417 wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
7419 struct btrfs_caching_control *caching_ctl;
7422 caching_ctl = get_caching_control(cache);
7424 return (cache->cached == BTRFS_CACHE_ERROR) ? -EIO : 0;
7426 wait_event(caching_ctl->wait, block_group_cache_done(cache));
7427 if (cache->cached == BTRFS_CACHE_ERROR)
7429 put_caching_control(caching_ctl);
7433 enum btrfs_loop_type {
7434 LOOP_CACHING_NOWAIT = 0,
7435 LOOP_CACHING_WAIT = 1,
7436 LOOP_ALLOC_CHUNK = 2,
7437 LOOP_NO_EMPTY_SIZE = 3,
7441 btrfs_lock_block_group(struct btrfs_block_group_cache *cache,
7445 down_read(&cache->data_rwsem);
7449 btrfs_grab_block_group(struct btrfs_block_group_cache *cache,
7452 btrfs_get_block_group(cache);
7454 down_read(&cache->data_rwsem);
7457 static struct btrfs_block_group_cache *
7458 btrfs_lock_cluster(struct btrfs_block_group_cache *block_group,
7459 struct btrfs_free_cluster *cluster,
7462 struct btrfs_block_group_cache *used_bg = NULL;
7464 spin_lock(&cluster->refill_lock);
7466 used_bg = cluster->block_group;
7470 if (used_bg == block_group)
7473 btrfs_get_block_group(used_bg);
7478 if (down_read_trylock(&used_bg->data_rwsem))
7481 spin_unlock(&cluster->refill_lock);
7483 /* We should only have one-level nested. */
7484 down_read_nested(&used_bg->data_rwsem, SINGLE_DEPTH_NESTING);
7486 spin_lock(&cluster->refill_lock);
7487 if (used_bg == cluster->block_group)
7490 up_read(&used_bg->data_rwsem);
7491 btrfs_put_block_group(used_bg);
7496 btrfs_release_block_group(struct btrfs_block_group_cache *cache,
7500 up_read(&cache->data_rwsem);
7501 btrfs_put_block_group(cache);
7505 * Structure used internally for find_free_extent() function. Wraps needed
7508 struct find_free_extent_ctl {
7509 /* Basic allocation info */
7516 /* Where to start the search inside the bg */
7519 /* For clustered allocation */
7522 bool have_caching_bg;
7523 bool orig_have_caching_bg;
7525 /* RAID index, converted from flags */
7529 * Current loop number, check find_free_extent_update_loop() for details
7534 * Whether we're refilling a cluster, if true we need to re-search
7535 * current block group but don't try to refill the cluster again.
7537 bool retry_clustered;
7540 * Whether we're updating free space cache, if true we need to re-search
7541 * current block group but don't try updating free space cache again.
7543 bool retry_unclustered;
7545 /* If current block group is cached */
7548 /* Max contiguous hole found */
7549 u64 max_extent_size;
7551 /* Total free space from free space cache, not always contiguous */
7552 u64 total_free_space;
7560 * Helper function for find_free_extent().
7562 * Return -ENOENT to inform caller that we need fallback to unclustered mode.
7563 * Return -EAGAIN to inform caller that we need to re-search this block group
7564 * Return >0 to inform caller that we find nothing
7565 * Return 0 means we have found a location and set ffe_ctl->found_offset.
7567 static int find_free_extent_clustered(struct btrfs_block_group_cache *bg,
7568 struct btrfs_free_cluster *last_ptr,
7569 struct find_free_extent_ctl *ffe_ctl,
7570 struct btrfs_block_group_cache **cluster_bg_ret)
7572 struct btrfs_fs_info *fs_info = bg->fs_info;
7573 struct btrfs_block_group_cache *cluster_bg;
7574 u64 aligned_cluster;
7578 cluster_bg = btrfs_lock_cluster(bg, last_ptr, ffe_ctl->delalloc);
7580 goto refill_cluster;
7581 if (cluster_bg != bg && (cluster_bg->ro ||
7582 !block_group_bits(cluster_bg, ffe_ctl->flags)))
7583 goto release_cluster;
7585 offset = btrfs_alloc_from_cluster(cluster_bg, last_ptr,
7586 ffe_ctl->num_bytes, cluster_bg->key.objectid,
7587 &ffe_ctl->max_extent_size);
7589 /* We have a block, we're done */
7590 spin_unlock(&last_ptr->refill_lock);
7591 trace_btrfs_reserve_extent_cluster(cluster_bg,
7592 ffe_ctl->search_start, ffe_ctl->num_bytes);
7593 *cluster_bg_ret = cluster_bg;
7594 ffe_ctl->found_offset = offset;
7597 WARN_ON(last_ptr->block_group != cluster_bg);
7601 * If we are on LOOP_NO_EMPTY_SIZE, we can't set up a new clusters, so
7602 * lets just skip it and let the allocator find whatever block it can
7603 * find. If we reach this point, we will have tried the cluster
7604 * allocator plenty of times and not have found anything, so we are
7605 * likely way too fragmented for the clustering stuff to find anything.
7607 * However, if the cluster is taken from the current block group,
7608 * release the cluster first, so that we stand a better chance of
7609 * succeeding in the unclustered allocation.
7611 if (ffe_ctl->loop >= LOOP_NO_EMPTY_SIZE && cluster_bg != bg) {
7612 spin_unlock(&last_ptr->refill_lock);
7613 btrfs_release_block_group(cluster_bg, ffe_ctl->delalloc);
7617 /* This cluster didn't work out, free it and start over */
7618 btrfs_return_cluster_to_free_space(NULL, last_ptr);
7620 if (cluster_bg != bg)
7621 btrfs_release_block_group(cluster_bg, ffe_ctl->delalloc);
7624 if (ffe_ctl->loop >= LOOP_NO_EMPTY_SIZE) {
7625 spin_unlock(&last_ptr->refill_lock);
7629 aligned_cluster = max_t(u64,
7630 ffe_ctl->empty_cluster + ffe_ctl->empty_size,
7631 bg->full_stripe_len);
7632 ret = btrfs_find_space_cluster(fs_info, bg, last_ptr,
7633 ffe_ctl->search_start, ffe_ctl->num_bytes,
7636 /* Now pull our allocation out of this cluster */
7637 offset = btrfs_alloc_from_cluster(bg, last_ptr,
7638 ffe_ctl->num_bytes, ffe_ctl->search_start,
7639 &ffe_ctl->max_extent_size);
7641 /* We found one, proceed */
7642 spin_unlock(&last_ptr->refill_lock);
7643 trace_btrfs_reserve_extent_cluster(bg,
7644 ffe_ctl->search_start,
7645 ffe_ctl->num_bytes);
7646 ffe_ctl->found_offset = offset;
7649 } else if (!ffe_ctl->cached && ffe_ctl->loop > LOOP_CACHING_NOWAIT &&
7650 !ffe_ctl->retry_clustered) {
7651 spin_unlock(&last_ptr->refill_lock);
7653 ffe_ctl->retry_clustered = true;
7654 wait_block_group_cache_progress(bg, ffe_ctl->num_bytes +
7655 ffe_ctl->empty_cluster + ffe_ctl->empty_size);
7659 * At this point we either didn't find a cluster or we weren't able to
7660 * allocate a block from our cluster. Free the cluster we've been
7661 * trying to use, and go to the next block group.
7663 btrfs_return_cluster_to_free_space(NULL, last_ptr);
7664 spin_unlock(&last_ptr->refill_lock);
7669 * Return >0 to inform caller that we find nothing
7670 * Return 0 when we found an free extent and set ffe_ctrl->found_offset
7671 * Return -EAGAIN to inform caller that we need to re-search this block group
7673 static int find_free_extent_unclustered(struct btrfs_block_group_cache *bg,
7674 struct btrfs_free_cluster *last_ptr,
7675 struct find_free_extent_ctl *ffe_ctl)
7680 * We are doing an unclustered allocation, set the fragmented flag so
7681 * we don't bother trying to setup a cluster again until we get more
7684 if (unlikely(last_ptr)) {
7685 spin_lock(&last_ptr->lock);
7686 last_ptr->fragmented = 1;
7687 spin_unlock(&last_ptr->lock);
7689 if (ffe_ctl->cached) {
7690 struct btrfs_free_space_ctl *free_space_ctl;
7692 free_space_ctl = bg->free_space_ctl;
7693 spin_lock(&free_space_ctl->tree_lock);
7694 if (free_space_ctl->free_space <
7695 ffe_ctl->num_bytes + ffe_ctl->empty_cluster +
7696 ffe_ctl->empty_size) {
7697 ffe_ctl->total_free_space = max_t(u64,
7698 ffe_ctl->total_free_space,
7699 free_space_ctl->free_space);
7700 spin_unlock(&free_space_ctl->tree_lock);
7703 spin_unlock(&free_space_ctl->tree_lock);
7706 offset = btrfs_find_space_for_alloc(bg, ffe_ctl->search_start,
7707 ffe_ctl->num_bytes, ffe_ctl->empty_size,
7708 &ffe_ctl->max_extent_size);
7711 * If we didn't find a chunk, and we haven't failed on this block group
7712 * before, and this block group is in the middle of caching and we are
7713 * ok with waiting, then go ahead and wait for progress to be made, and
7714 * set @retry_unclustered to true.
7716 * If @retry_unclustered is true then we've already waited on this
7717 * block group once and should move on to the next block group.
7719 if (!offset && !ffe_ctl->retry_unclustered && !ffe_ctl->cached &&
7720 ffe_ctl->loop > LOOP_CACHING_NOWAIT) {
7721 wait_block_group_cache_progress(bg, ffe_ctl->num_bytes +
7722 ffe_ctl->empty_size);
7723 ffe_ctl->retry_unclustered = true;
7725 } else if (!offset) {
7728 ffe_ctl->found_offset = offset;
7733 * Return >0 means caller needs to re-search for free extent
7734 * Return 0 means we have the needed free extent.
7735 * Return <0 means we failed to locate any free extent.
7737 static int find_free_extent_update_loop(struct btrfs_fs_info *fs_info,
7738 struct btrfs_free_cluster *last_ptr,
7739 struct btrfs_key *ins,
7740 struct find_free_extent_ctl *ffe_ctl,
7741 int full_search, bool use_cluster)
7743 struct btrfs_root *root = fs_info->extent_root;
7746 if ((ffe_ctl->loop == LOOP_CACHING_NOWAIT) &&
7747 ffe_ctl->have_caching_bg && !ffe_ctl->orig_have_caching_bg)
7748 ffe_ctl->orig_have_caching_bg = true;
7750 if (!ins->objectid && ffe_ctl->loop >= LOOP_CACHING_WAIT &&
7751 ffe_ctl->have_caching_bg)
7754 if (!ins->objectid && ++(ffe_ctl->index) < BTRFS_NR_RAID_TYPES)
7757 if (ins->objectid) {
7758 if (!use_cluster && last_ptr) {
7759 spin_lock(&last_ptr->lock);
7760 last_ptr->window_start = ins->objectid;
7761 spin_unlock(&last_ptr->lock);
7767 * LOOP_CACHING_NOWAIT, search partially cached block groups, kicking
7768 * caching kthreads as we move along
7769 * LOOP_CACHING_WAIT, search everything, and wait if our bg is caching
7770 * LOOP_ALLOC_CHUNK, force a chunk allocation and try again
7771 * LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try
7774 if (ffe_ctl->loop < LOOP_NO_EMPTY_SIZE) {
7776 if (ffe_ctl->loop == LOOP_CACHING_NOWAIT) {
7778 * We want to skip the LOOP_CACHING_WAIT step if we
7779 * don't have any uncached bgs and we've already done a
7780 * full search through.
7782 if (ffe_ctl->orig_have_caching_bg || !full_search)
7783 ffe_ctl->loop = LOOP_CACHING_WAIT;
7785 ffe_ctl->loop = LOOP_ALLOC_CHUNK;
7790 if (ffe_ctl->loop == LOOP_ALLOC_CHUNK) {
7791 struct btrfs_trans_handle *trans;
7794 trans = current->journal_info;
7798 trans = btrfs_join_transaction(root);
7800 if (IS_ERR(trans)) {
7801 ret = PTR_ERR(trans);
7805 ret = do_chunk_alloc(trans, ffe_ctl->flags,
7809 * If we can't allocate a new chunk we've already looped
7810 * through at least once, move on to the NO_EMPTY_SIZE
7814 ffe_ctl->loop = LOOP_NO_EMPTY_SIZE;
7816 /* Do not bail out on ENOSPC since we can do more. */
7817 if (ret < 0 && ret != -ENOSPC)
7818 btrfs_abort_transaction(trans, ret);
7822 btrfs_end_transaction(trans);
7827 if (ffe_ctl->loop == LOOP_NO_EMPTY_SIZE) {
7829 * Don't loop again if we already have no empty_size and
7832 if (ffe_ctl->empty_size == 0 &&
7833 ffe_ctl->empty_cluster == 0)
7835 ffe_ctl->empty_size = 0;
7836 ffe_ctl->empty_cluster = 0;
7844 * walks the btree of allocated extents and find a hole of a given size.
7845 * The key ins is changed to record the hole:
7846 * ins->objectid == start position
7847 * ins->flags = BTRFS_EXTENT_ITEM_KEY
7848 * ins->offset == the size of the hole.
7849 * Any available blocks before search_start are skipped.
7851 * If there is no suitable free space, we will record the max size of
7852 * the free space extent currently.
7854 * The overall logic and call chain:
7856 * find_free_extent()
7857 * |- Iterate through all block groups
7858 * | |- Get a valid block group
7859 * | |- Try to do clustered allocation in that block group
7860 * | |- Try to do unclustered allocation in that block group
7861 * | |- Check if the result is valid
7862 * | | |- If valid, then exit
7863 * | |- Jump to next block group
7865 * |- Push harder to find free extents
7866 * |- If not found, re-iterate all block groups
7868 static noinline int find_free_extent(struct btrfs_fs_info *fs_info,
7869 u64 ram_bytes, u64 num_bytes, u64 empty_size,
7870 u64 hint_byte, struct btrfs_key *ins,
7871 u64 flags, int delalloc)
7874 struct btrfs_free_cluster *last_ptr = NULL;
7875 struct btrfs_block_group_cache *block_group = NULL;
7876 struct find_free_extent_ctl ffe_ctl = {0};
7877 struct btrfs_space_info *space_info;
7878 bool use_cluster = true;
7879 bool full_search = false;
7881 WARN_ON(num_bytes < fs_info->sectorsize);
7883 ffe_ctl.ram_bytes = ram_bytes;
7884 ffe_ctl.num_bytes = num_bytes;
7885 ffe_ctl.empty_size = empty_size;
7886 ffe_ctl.flags = flags;
7887 ffe_ctl.search_start = 0;
7888 ffe_ctl.retry_clustered = false;
7889 ffe_ctl.retry_unclustered = false;
7890 ffe_ctl.delalloc = delalloc;
7891 ffe_ctl.index = btrfs_bg_flags_to_raid_index(flags);
7892 ffe_ctl.have_caching_bg = false;
7893 ffe_ctl.orig_have_caching_bg = false;
7894 ffe_ctl.found_offset = 0;
7896 ins->type = BTRFS_EXTENT_ITEM_KEY;
7900 trace_find_free_extent(fs_info, num_bytes, empty_size, flags);
7902 space_info = __find_space_info(fs_info, flags);
7904 btrfs_err(fs_info, "No space info for %llu", flags);
7909 * If our free space is heavily fragmented we may not be able to make
7910 * big contiguous allocations, so instead of doing the expensive search
7911 * for free space, simply return ENOSPC with our max_extent_size so we
7912 * can go ahead and search for a more manageable chunk.
7914 * If our max_extent_size is large enough for our allocation simply
7915 * disable clustering since we will likely not be able to find enough
7916 * space to create a cluster and induce latency trying.
7918 if (unlikely(space_info->max_extent_size)) {
7919 spin_lock(&space_info->lock);
7920 if (space_info->max_extent_size &&
7921 num_bytes > space_info->max_extent_size) {
7922 ins->offset = space_info->max_extent_size;
7923 spin_unlock(&space_info->lock);
7925 } else if (space_info->max_extent_size) {
7926 use_cluster = false;
7928 spin_unlock(&space_info->lock);
7931 last_ptr = fetch_cluster_info(fs_info, space_info,
7932 &ffe_ctl.empty_cluster);
7934 spin_lock(&last_ptr->lock);
7935 if (last_ptr->block_group)
7936 hint_byte = last_ptr->window_start;
7937 if (last_ptr->fragmented) {
7939 * We still set window_start so we can keep track of the
7940 * last place we found an allocation to try and save
7943 hint_byte = last_ptr->window_start;
7944 use_cluster = false;
7946 spin_unlock(&last_ptr->lock);
7949 ffe_ctl.search_start = max(ffe_ctl.search_start,
7950 first_logical_byte(fs_info, 0));
7951 ffe_ctl.search_start = max(ffe_ctl.search_start, hint_byte);
7952 if (ffe_ctl.search_start == hint_byte) {
7953 block_group = btrfs_lookup_block_group(fs_info,
7954 ffe_ctl.search_start);
7956 * we don't want to use the block group if it doesn't match our
7957 * allocation bits, or if its not cached.
7959 * However if we are re-searching with an ideal block group
7960 * picked out then we don't care that the block group is cached.
7962 if (block_group && block_group_bits(block_group, flags) &&
7963 block_group->cached != BTRFS_CACHE_NO) {
7964 down_read(&space_info->groups_sem);
7965 if (list_empty(&block_group->list) ||
7968 * someone is removing this block group,
7969 * we can't jump into the have_block_group
7970 * target because our list pointers are not
7973 btrfs_put_block_group(block_group);
7974 up_read(&space_info->groups_sem);
7976 ffe_ctl.index = btrfs_bg_flags_to_raid_index(
7977 block_group->flags);
7978 btrfs_lock_block_group(block_group, delalloc);
7979 goto have_block_group;
7981 } else if (block_group) {
7982 btrfs_put_block_group(block_group);
7986 ffe_ctl.have_caching_bg = false;
7987 if (ffe_ctl.index == btrfs_bg_flags_to_raid_index(flags) ||
7990 down_read(&space_info->groups_sem);
7991 list_for_each_entry(block_group,
7992 &space_info->block_groups[ffe_ctl.index], list) {
7993 /* If the block group is read-only, we can skip it entirely. */
7994 if (unlikely(block_group->ro))
7997 btrfs_grab_block_group(block_group, delalloc);
7998 ffe_ctl.search_start = block_group->key.objectid;
8001 * this can happen if we end up cycling through all the
8002 * raid types, but we want to make sure we only allocate
8003 * for the proper type.
8005 if (!block_group_bits(block_group, flags)) {
8006 u64 extra = BTRFS_BLOCK_GROUP_DUP |
8007 BTRFS_BLOCK_GROUP_RAID1 |
8008 BTRFS_BLOCK_GROUP_RAID5 |
8009 BTRFS_BLOCK_GROUP_RAID6 |
8010 BTRFS_BLOCK_GROUP_RAID10;
8013 * if they asked for extra copies and this block group
8014 * doesn't provide them, bail. This does allow us to
8015 * fill raid0 from raid1.
8017 if ((flags & extra) && !(block_group->flags & extra))
8022 ffe_ctl.cached = block_group_cache_done(block_group);
8023 if (unlikely(!ffe_ctl.cached)) {
8024 ffe_ctl.have_caching_bg = true;
8025 ret = cache_block_group(block_group, 0);
8030 if (unlikely(block_group->cached == BTRFS_CACHE_ERROR))
8034 * Ok we want to try and use the cluster allocator, so
8037 if (last_ptr && use_cluster) {
8038 struct btrfs_block_group_cache *cluster_bg = NULL;
8040 ret = find_free_extent_clustered(block_group, last_ptr,
8041 &ffe_ctl, &cluster_bg);
8044 if (cluster_bg && cluster_bg != block_group) {
8045 btrfs_release_block_group(block_group,
8047 block_group = cluster_bg;
8050 } else if (ret == -EAGAIN) {
8051 goto have_block_group;
8052 } else if (ret > 0) {
8055 /* ret == -ENOENT case falls through */
8058 ret = find_free_extent_unclustered(block_group, last_ptr,
8061 goto have_block_group;
8064 /* ret == 0 case falls through */
8066 ffe_ctl.search_start = round_up(ffe_ctl.found_offset,
8067 fs_info->stripesize);
8069 /* move on to the next group */
8070 if (ffe_ctl.search_start + num_bytes >
8071 block_group->key.objectid + block_group->key.offset) {
8072 btrfs_add_free_space(block_group, ffe_ctl.found_offset,
8077 if (ffe_ctl.found_offset < ffe_ctl.search_start)
8078 btrfs_add_free_space(block_group, ffe_ctl.found_offset,
8079 ffe_ctl.search_start - ffe_ctl.found_offset);
8081 ret = btrfs_add_reserved_bytes(block_group, ram_bytes,
8082 num_bytes, delalloc);
8083 if (ret == -EAGAIN) {
8084 btrfs_add_free_space(block_group, ffe_ctl.found_offset,
8088 btrfs_inc_block_group_reservations(block_group);
8090 /* we are all good, lets return */
8091 ins->objectid = ffe_ctl.search_start;
8092 ins->offset = num_bytes;
8094 trace_btrfs_reserve_extent(block_group, ffe_ctl.search_start,
8096 btrfs_release_block_group(block_group, delalloc);
8099 ffe_ctl.retry_clustered = false;
8100 ffe_ctl.retry_unclustered = false;
8101 BUG_ON(btrfs_bg_flags_to_raid_index(block_group->flags) !=
8103 btrfs_release_block_group(block_group, delalloc);
8106 up_read(&space_info->groups_sem);
8108 ret = find_free_extent_update_loop(fs_info, last_ptr, ins, &ffe_ctl,
8109 full_search, use_cluster);
8113 if (ret == -ENOSPC) {
8115 * Use ffe_ctl->total_free_space as fallback if we can't find
8116 * any contiguous hole.
8118 if (!ffe_ctl.max_extent_size)
8119 ffe_ctl.max_extent_size = ffe_ctl.total_free_space;
8120 spin_lock(&space_info->lock);
8121 space_info->max_extent_size = ffe_ctl.max_extent_size;
8122 spin_unlock(&space_info->lock);
8123 ins->offset = ffe_ctl.max_extent_size;
8128 #define DUMP_BLOCK_RSV(fs_info, rsv_name) \
8130 struct btrfs_block_rsv *__rsv = &(fs_info)->rsv_name; \
8131 spin_lock(&__rsv->lock); \
8132 btrfs_info(fs_info, #rsv_name ": size %llu reserved %llu", \
8133 __rsv->size, __rsv->reserved); \
8134 spin_unlock(&__rsv->lock); \
8137 static void dump_space_info(struct btrfs_fs_info *fs_info,
8138 struct btrfs_space_info *info, u64 bytes,
8139 int dump_block_groups)
8141 struct btrfs_block_group_cache *cache;
8144 spin_lock(&info->lock);
8145 btrfs_info(fs_info, "space_info %llu has %llu free, is %sfull",
8147 info->total_bytes - btrfs_space_info_used(info, true),
8148 info->full ? "" : "not ");
8150 "space_info total=%llu, used=%llu, pinned=%llu, reserved=%llu, may_use=%llu, readonly=%llu",
8151 info->total_bytes, info->bytes_used, info->bytes_pinned,
8152 info->bytes_reserved, info->bytes_may_use,
8153 info->bytes_readonly);
8154 spin_unlock(&info->lock);
8156 DUMP_BLOCK_RSV(fs_info, global_block_rsv);
8157 DUMP_BLOCK_RSV(fs_info, trans_block_rsv);
8158 DUMP_BLOCK_RSV(fs_info, chunk_block_rsv);
8159 DUMP_BLOCK_RSV(fs_info, delayed_block_rsv);
8160 DUMP_BLOCK_RSV(fs_info, delayed_refs_rsv);
8162 if (!dump_block_groups)
8165 down_read(&info->groups_sem);
8167 list_for_each_entry(cache, &info->block_groups[index], list) {
8168 spin_lock(&cache->lock);
8170 "block group %llu has %llu bytes, %llu used %llu pinned %llu reserved %s",
8171 cache->key.objectid, cache->key.offset,
8172 btrfs_block_group_used(&cache->item), cache->pinned,
8173 cache->reserved, cache->ro ? "[readonly]" : "");
8174 btrfs_dump_free_space(cache, bytes);
8175 spin_unlock(&cache->lock);
8177 if (++index < BTRFS_NR_RAID_TYPES)
8179 up_read(&info->groups_sem);
8183 * btrfs_reserve_extent - entry point to the extent allocator. Tries to find a
8184 * hole that is at least as big as @num_bytes.
8186 * @root - The root that will contain this extent
8188 * @ram_bytes - The amount of space in ram that @num_bytes take. This
8189 * is used for accounting purposes. This value differs
8190 * from @num_bytes only in the case of compressed extents.
8192 * @num_bytes - Number of bytes to allocate on-disk.
8194 * @min_alloc_size - Indicates the minimum amount of space that the
8195 * allocator should try to satisfy. In some cases
8196 * @num_bytes may be larger than what is required and if
8197 * the filesystem is fragmented then allocation fails.
8198 * However, the presence of @min_alloc_size gives a
8199 * chance to try and satisfy the smaller allocation.
8201 * @empty_size - A hint that you plan on doing more COW. This is the
8202 * size in bytes the allocator should try to find free
8203 * next to the block it returns. This is just a hint and
8204 * may be ignored by the allocator.
8206 * @hint_byte - Hint to the allocator to start searching above the byte
8207 * address passed. It might be ignored.
8209 * @ins - This key is modified to record the found hole. It will
8210 * have the following values:
8211 * ins->objectid == start position
8212 * ins->flags = BTRFS_EXTENT_ITEM_KEY
8213 * ins->offset == the size of the hole.
8215 * @is_data - Boolean flag indicating whether an extent is
8216 * allocated for data (true) or metadata (false)
8218 * @delalloc - Boolean flag indicating whether this allocation is for
8219 * delalloc or not. If 'true' data_rwsem of block groups
8220 * is going to be acquired.
8223 * Returns 0 when an allocation succeeded or < 0 when an error occurred. In
8224 * case -ENOSPC is returned then @ins->offset will contain the size of the
8225 * largest available hole the allocator managed to find.
8227 int btrfs_reserve_extent(struct btrfs_root *root, u64 ram_bytes,
8228 u64 num_bytes, u64 min_alloc_size,
8229 u64 empty_size, u64 hint_byte,
8230 struct btrfs_key *ins, int is_data, int delalloc)
8232 struct btrfs_fs_info *fs_info = root->fs_info;
8233 bool final_tried = num_bytes == min_alloc_size;
8237 flags = get_alloc_profile_by_root(root, is_data);
8239 WARN_ON(num_bytes < fs_info->sectorsize);
8240 ret = find_free_extent(fs_info, ram_bytes, num_bytes, empty_size,
8241 hint_byte, ins, flags, delalloc);
8242 if (!ret && !is_data) {
8243 btrfs_dec_block_group_reservations(fs_info, ins->objectid);
8244 } else if (ret == -ENOSPC) {
8245 if (!final_tried && ins->offset) {
8246 num_bytes = min(num_bytes >> 1, ins->offset);
8247 num_bytes = round_down(num_bytes,
8248 fs_info->sectorsize);
8249 num_bytes = max(num_bytes, min_alloc_size);
8250 ram_bytes = num_bytes;
8251 if (num_bytes == min_alloc_size)
8254 } else if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
8255 struct btrfs_space_info *sinfo;
8257 sinfo = __find_space_info(fs_info, flags);
8259 "allocation failed flags %llu, wanted %llu",
8262 dump_space_info(fs_info, sinfo, num_bytes, 1);
8269 static int __btrfs_free_reserved_extent(struct btrfs_fs_info *fs_info,
8271 int pin, int delalloc)
8273 struct btrfs_block_group_cache *cache;
8276 cache = btrfs_lookup_block_group(fs_info, start);
8278 btrfs_err(fs_info, "Unable to find block group for %llu",
8284 pin_down_extent(fs_info, cache, start, len, 1);
8286 if (btrfs_test_opt(fs_info, DISCARD))
8287 ret = btrfs_discard_extent(fs_info, start, len, NULL);
8288 btrfs_add_free_space(cache, start, len);
8289 btrfs_free_reserved_bytes(cache, len, delalloc);
8290 trace_btrfs_reserved_extent_free(fs_info, start, len);
8293 btrfs_put_block_group(cache);
8297 int btrfs_free_reserved_extent(struct btrfs_fs_info *fs_info,
8298 u64 start, u64 len, int delalloc)
8300 return __btrfs_free_reserved_extent(fs_info, start, len, 0, delalloc);
8303 int btrfs_free_and_pin_reserved_extent(struct btrfs_fs_info *fs_info,
8306 return __btrfs_free_reserved_extent(fs_info, start, len, 1, 0);
8309 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
8310 u64 parent, u64 root_objectid,
8311 u64 flags, u64 owner, u64 offset,
8312 struct btrfs_key *ins, int ref_mod)
8314 struct btrfs_fs_info *fs_info = trans->fs_info;
8316 struct btrfs_extent_item *extent_item;
8317 struct btrfs_extent_inline_ref *iref;
8318 struct btrfs_path *path;
8319 struct extent_buffer *leaf;
8324 type = BTRFS_SHARED_DATA_REF_KEY;
8326 type = BTRFS_EXTENT_DATA_REF_KEY;
8328 size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type);
8330 path = btrfs_alloc_path();
8334 path->leave_spinning = 1;
8335 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
8338 btrfs_free_path(path);
8342 leaf = path->nodes[0];
8343 extent_item = btrfs_item_ptr(leaf, path->slots[0],
8344 struct btrfs_extent_item);
8345 btrfs_set_extent_refs(leaf, extent_item, ref_mod);
8346 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
8347 btrfs_set_extent_flags(leaf, extent_item,
8348 flags | BTRFS_EXTENT_FLAG_DATA);
8350 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
8351 btrfs_set_extent_inline_ref_type(leaf, iref, type);
8353 struct btrfs_shared_data_ref *ref;
8354 ref = (struct btrfs_shared_data_ref *)(iref + 1);
8355 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
8356 btrfs_set_shared_data_ref_count(leaf, ref, ref_mod);
8358 struct btrfs_extent_data_ref *ref;
8359 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
8360 btrfs_set_extent_data_ref_root(leaf, ref, root_objectid);
8361 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
8362 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
8363 btrfs_set_extent_data_ref_count(leaf, ref, ref_mod);
8366 btrfs_mark_buffer_dirty(path->nodes[0]);
8367 btrfs_free_path(path);
8369 ret = remove_from_free_space_tree(trans, ins->objectid, ins->offset);
8373 ret = update_block_group(trans, fs_info, ins->objectid, ins->offset, 1);
8374 if (ret) { /* -ENOENT, logic error */
8375 btrfs_err(fs_info, "update block group failed for %llu %llu",
8376 ins->objectid, ins->offset);
8379 trace_btrfs_reserved_extent_alloc(fs_info, ins->objectid, ins->offset);
8383 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
8384 struct btrfs_delayed_ref_node *node,
8385 struct btrfs_delayed_extent_op *extent_op)
8387 struct btrfs_fs_info *fs_info = trans->fs_info;
8389 struct btrfs_extent_item *extent_item;
8390 struct btrfs_key extent_key;
8391 struct btrfs_tree_block_info *block_info;
8392 struct btrfs_extent_inline_ref *iref;
8393 struct btrfs_path *path;
8394 struct extent_buffer *leaf;
8395 struct btrfs_delayed_tree_ref *ref;
8396 u32 size = sizeof(*extent_item) + sizeof(*iref);
8398 u64 flags = extent_op->flags_to_set;
8399 bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
8401 ref = btrfs_delayed_node_to_tree_ref(node);
8403 extent_key.objectid = node->bytenr;
8404 if (skinny_metadata) {
8405 extent_key.offset = ref->level;
8406 extent_key.type = BTRFS_METADATA_ITEM_KEY;
8407 num_bytes = fs_info->nodesize;
8409 extent_key.offset = node->num_bytes;
8410 extent_key.type = BTRFS_EXTENT_ITEM_KEY;
8411 size += sizeof(*block_info);
8412 num_bytes = node->num_bytes;
8415 path = btrfs_alloc_path();
8419 path->leave_spinning = 1;
8420 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
8423 btrfs_free_path(path);
8427 leaf = path->nodes[0];
8428 extent_item = btrfs_item_ptr(leaf, path->slots[0],
8429 struct btrfs_extent_item);
8430 btrfs_set_extent_refs(leaf, extent_item, 1);
8431 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
8432 btrfs_set_extent_flags(leaf, extent_item,
8433 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
8435 if (skinny_metadata) {
8436 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
8438 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
8439 btrfs_set_tree_block_key(leaf, block_info, &extent_op->key);
8440 btrfs_set_tree_block_level(leaf, block_info, ref->level);
8441 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
8444 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY) {
8445 BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF));
8446 btrfs_set_extent_inline_ref_type(leaf, iref,
8447 BTRFS_SHARED_BLOCK_REF_KEY);
8448 btrfs_set_extent_inline_ref_offset(leaf, iref, ref->parent);
8450 btrfs_set_extent_inline_ref_type(leaf, iref,
8451 BTRFS_TREE_BLOCK_REF_KEY);
8452 btrfs_set_extent_inline_ref_offset(leaf, iref, ref->root);
8455 btrfs_mark_buffer_dirty(leaf);
8456 btrfs_free_path(path);
8458 ret = remove_from_free_space_tree(trans, extent_key.objectid,
8463 ret = update_block_group(trans, fs_info, extent_key.objectid,
8464 fs_info->nodesize, 1);
8465 if (ret) { /* -ENOENT, logic error */
8466 btrfs_err(fs_info, "update block group failed for %llu %llu",
8467 extent_key.objectid, extent_key.offset);
8471 trace_btrfs_reserved_extent_alloc(fs_info, extent_key.objectid,
8476 int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
8477 struct btrfs_root *root, u64 owner,
8478 u64 offset, u64 ram_bytes,
8479 struct btrfs_key *ins)
8483 BUG_ON(root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID);
8485 btrfs_ref_tree_mod(root, ins->objectid, ins->offset, 0,
8486 root->root_key.objectid, owner, offset,
8487 BTRFS_ADD_DELAYED_EXTENT);
8489 ret = btrfs_add_delayed_data_ref(trans, ins->objectid,
8491 root->root_key.objectid, owner,
8493 BTRFS_ADD_DELAYED_EXTENT, NULL, NULL);
8498 * this is used by the tree logging recovery code. It records that
8499 * an extent has been allocated and makes sure to clear the free
8500 * space cache bits as well
8502 int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
8503 u64 root_objectid, u64 owner, u64 offset,
8504 struct btrfs_key *ins)
8506 struct btrfs_fs_info *fs_info = trans->fs_info;
8508 struct btrfs_block_group_cache *block_group;
8509 struct btrfs_space_info *space_info;
8512 * Mixed block groups will exclude before processing the log so we only
8513 * need to do the exclude dance if this fs isn't mixed.
8515 if (!btrfs_fs_incompat(fs_info, MIXED_GROUPS)) {
8516 ret = __exclude_logged_extent(fs_info, ins->objectid,
8522 block_group = btrfs_lookup_block_group(fs_info, ins->objectid);
8526 space_info = block_group->space_info;
8527 spin_lock(&space_info->lock);
8528 spin_lock(&block_group->lock);
8529 space_info->bytes_reserved += ins->offset;
8530 block_group->reserved += ins->offset;
8531 spin_unlock(&block_group->lock);
8532 spin_unlock(&space_info->lock);
8534 ret = alloc_reserved_file_extent(trans, 0, root_objectid, 0, owner,
8536 btrfs_put_block_group(block_group);
8540 static struct extent_buffer *
8541 btrfs_init_new_buffer(struct btrfs_trans_handle *trans, struct btrfs_root *root,
8542 u64 bytenr, int level, u64 owner)
8544 struct btrfs_fs_info *fs_info = root->fs_info;
8545 struct extent_buffer *buf;
8547 buf = btrfs_find_create_tree_block(fs_info, bytenr);
8552 * Extra safety check in case the extent tree is corrupted and extent
8553 * allocator chooses to use a tree block which is already used and
8556 if (buf->lock_owner == current->pid) {
8557 btrfs_err_rl(fs_info,
8558 "tree block %llu owner %llu already locked by pid=%d, extent tree corruption detected",
8559 buf->start, btrfs_header_owner(buf), current->pid);
8560 free_extent_buffer(buf);
8561 return ERR_PTR(-EUCLEAN);
8564 btrfs_set_buffer_lockdep_class(root->root_key.objectid, buf, level);
8565 btrfs_tree_lock(buf);
8566 clean_tree_block(fs_info, buf);
8567 clear_bit(EXTENT_BUFFER_STALE, &buf->bflags);
8569 btrfs_set_lock_blocking_write(buf);
8570 set_extent_buffer_uptodate(buf);
8572 memzero_extent_buffer(buf, 0, sizeof(struct btrfs_header));
8573 btrfs_set_header_level(buf, level);
8574 btrfs_set_header_bytenr(buf, buf->start);
8575 btrfs_set_header_generation(buf, trans->transid);
8576 btrfs_set_header_backref_rev(buf, BTRFS_MIXED_BACKREF_REV);
8577 btrfs_set_header_owner(buf, owner);
8578 write_extent_buffer_fsid(buf, fs_info->fs_devices->metadata_uuid);
8579 write_extent_buffer_chunk_tree_uuid(buf, fs_info->chunk_tree_uuid);
8580 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
8581 buf->log_index = root->log_transid % 2;
8583 * we allow two log transactions at a time, use different
8584 * EXTENT bit to differentiate dirty pages.
8586 if (buf->log_index == 0)
8587 set_extent_dirty(&root->dirty_log_pages, buf->start,
8588 buf->start + buf->len - 1, GFP_NOFS);
8590 set_extent_new(&root->dirty_log_pages, buf->start,
8591 buf->start + buf->len - 1);
8593 buf->log_index = -1;
8594 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
8595 buf->start + buf->len - 1, GFP_NOFS);
8597 trans->dirty = true;
8598 /* this returns a buffer locked for blocking */
8602 static struct btrfs_block_rsv *
8603 use_block_rsv(struct btrfs_trans_handle *trans,
8604 struct btrfs_root *root, u32 blocksize)
8606 struct btrfs_fs_info *fs_info = root->fs_info;
8607 struct btrfs_block_rsv *block_rsv;
8608 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
8610 bool global_updated = false;
8612 block_rsv = get_block_rsv(trans, root);
8614 if (unlikely(block_rsv->size == 0))
8617 ret = block_rsv_use_bytes(block_rsv, blocksize);
8621 if (block_rsv->failfast)
8622 return ERR_PTR(ret);
8624 if (block_rsv->type == BTRFS_BLOCK_RSV_GLOBAL && !global_updated) {
8625 global_updated = true;
8626 update_global_block_rsv(fs_info);
8631 * The global reserve still exists to save us from ourselves, so don't
8632 * warn_on if we are short on our delayed refs reserve.
8634 if (block_rsv->type != BTRFS_BLOCK_RSV_DELREFS &&
8635 btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
8636 static DEFINE_RATELIMIT_STATE(_rs,
8637 DEFAULT_RATELIMIT_INTERVAL * 10,
8638 /*DEFAULT_RATELIMIT_BURST*/ 1);
8639 if (__ratelimit(&_rs))
8641 "BTRFS: block rsv returned %d\n", ret);
8644 ret = reserve_metadata_bytes(root, block_rsv, blocksize,
8645 BTRFS_RESERVE_NO_FLUSH);
8649 * If we couldn't reserve metadata bytes try and use some from
8650 * the global reserve if its space type is the same as the global
8653 if (block_rsv->type != BTRFS_BLOCK_RSV_GLOBAL &&
8654 block_rsv->space_info == global_rsv->space_info) {
8655 ret = block_rsv_use_bytes(global_rsv, blocksize);
8659 return ERR_PTR(ret);
8662 static void unuse_block_rsv(struct btrfs_fs_info *fs_info,
8663 struct btrfs_block_rsv *block_rsv, u32 blocksize)
8665 block_rsv_add_bytes(block_rsv, blocksize, false);
8666 block_rsv_release_bytes(fs_info, block_rsv, NULL, 0, NULL);
8670 * finds a free extent and does all the dirty work required for allocation
8671 * returns the tree buffer or an ERR_PTR on error.
8673 struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans,
8674 struct btrfs_root *root,
8675 u64 parent, u64 root_objectid,
8676 const struct btrfs_disk_key *key,
8677 int level, u64 hint,
8680 struct btrfs_fs_info *fs_info = root->fs_info;
8681 struct btrfs_key ins;
8682 struct btrfs_block_rsv *block_rsv;
8683 struct extent_buffer *buf;
8684 struct btrfs_delayed_extent_op *extent_op;
8687 u32 blocksize = fs_info->nodesize;
8688 bool skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
8690 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
8691 if (btrfs_is_testing(fs_info)) {
8692 buf = btrfs_init_new_buffer(trans, root, root->alloc_bytenr,
8693 level, root_objectid);
8695 root->alloc_bytenr += blocksize;
8700 block_rsv = use_block_rsv(trans, root, blocksize);
8701 if (IS_ERR(block_rsv))
8702 return ERR_CAST(block_rsv);
8704 ret = btrfs_reserve_extent(root, blocksize, blocksize, blocksize,
8705 empty_size, hint, &ins, 0, 0);
8709 buf = btrfs_init_new_buffer(trans, root, ins.objectid, level,
8713 goto out_free_reserved;
8716 if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
8718 parent = ins.objectid;
8719 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
8723 if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
8724 extent_op = btrfs_alloc_delayed_extent_op();
8730 memcpy(&extent_op->key, key, sizeof(extent_op->key));
8732 memset(&extent_op->key, 0, sizeof(extent_op->key));
8733 extent_op->flags_to_set = flags;
8734 extent_op->update_key = skinny_metadata ? false : true;
8735 extent_op->update_flags = true;
8736 extent_op->is_data = false;
8737 extent_op->level = level;
8739 btrfs_ref_tree_mod(root, ins.objectid, ins.offset, parent,
8740 root_objectid, level, 0,
8741 BTRFS_ADD_DELAYED_EXTENT);
8742 ret = btrfs_add_delayed_tree_ref(trans, ins.objectid,
8744 root_objectid, level,
8745 BTRFS_ADD_DELAYED_EXTENT,
8746 extent_op, NULL, NULL);
8748 goto out_free_delayed;
8753 btrfs_free_delayed_extent_op(extent_op);
8755 free_extent_buffer(buf);
8757 btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 0);
8759 unuse_block_rsv(fs_info, block_rsv, blocksize);
8760 return ERR_PTR(ret);
8763 struct walk_control {
8764 u64 refs[BTRFS_MAX_LEVEL];
8765 u64 flags[BTRFS_MAX_LEVEL];
8766 struct btrfs_key update_progress;
8767 struct btrfs_key drop_progress;
8779 #define DROP_REFERENCE 1
8780 #define UPDATE_BACKREF 2
8782 static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
8783 struct btrfs_root *root,
8784 struct walk_control *wc,
8785 struct btrfs_path *path)
8787 struct btrfs_fs_info *fs_info = root->fs_info;
8793 struct btrfs_key key;
8794 struct extent_buffer *eb;
8799 if (path->slots[wc->level] < wc->reada_slot) {
8800 wc->reada_count = wc->reada_count * 2 / 3;
8801 wc->reada_count = max(wc->reada_count, 2);
8803 wc->reada_count = wc->reada_count * 3 / 2;
8804 wc->reada_count = min_t(int, wc->reada_count,
8805 BTRFS_NODEPTRS_PER_BLOCK(fs_info));
8808 eb = path->nodes[wc->level];
8809 nritems = btrfs_header_nritems(eb);
8811 for (slot = path->slots[wc->level]; slot < nritems; slot++) {
8812 if (nread >= wc->reada_count)
8816 bytenr = btrfs_node_blockptr(eb, slot);
8817 generation = btrfs_node_ptr_generation(eb, slot);
8819 if (slot == path->slots[wc->level])
8822 if (wc->stage == UPDATE_BACKREF &&
8823 generation <= root->root_key.offset)
8826 /* We don't lock the tree block, it's OK to be racy here */
8827 ret = btrfs_lookup_extent_info(trans, fs_info, bytenr,
8828 wc->level - 1, 1, &refs,
8830 /* We don't care about errors in readahead. */
8835 if (wc->stage == DROP_REFERENCE) {
8839 if (wc->level == 1 &&
8840 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
8842 if (!wc->update_ref ||
8843 generation <= root->root_key.offset)
8845 btrfs_node_key_to_cpu(eb, &key, slot);
8846 ret = btrfs_comp_cpu_keys(&key,
8847 &wc->update_progress);
8851 if (wc->level == 1 &&
8852 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
8856 readahead_tree_block(fs_info, bytenr);
8859 wc->reada_slot = slot;
8863 * helper to process tree block while walking down the tree.
8865 * when wc->stage == UPDATE_BACKREF, this function updates
8866 * back refs for pointers in the block.
8868 * NOTE: return value 1 means we should stop walking down.
8870 static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
8871 struct btrfs_root *root,
8872 struct btrfs_path *path,
8873 struct walk_control *wc, int lookup_info)
8875 struct btrfs_fs_info *fs_info = root->fs_info;
8876 int level = wc->level;
8877 struct extent_buffer *eb = path->nodes[level];
8878 u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF;
8881 if (wc->stage == UPDATE_BACKREF &&
8882 btrfs_header_owner(eb) != root->root_key.objectid)
8886 * when reference count of tree block is 1, it won't increase
8887 * again. once full backref flag is set, we never clear it.
8890 ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
8891 (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag)))) {
8892 BUG_ON(!path->locks[level]);
8893 ret = btrfs_lookup_extent_info(trans, fs_info,
8894 eb->start, level, 1,
8897 BUG_ON(ret == -ENOMEM);
8900 BUG_ON(wc->refs[level] == 0);
8903 if (wc->stage == DROP_REFERENCE) {
8904 if (wc->refs[level] > 1)
8907 if (path->locks[level] && !wc->keep_locks) {
8908 btrfs_tree_unlock_rw(eb, path->locks[level]);
8909 path->locks[level] = 0;
8914 /* wc->stage == UPDATE_BACKREF */
8915 if (!(wc->flags[level] & flag)) {
8916 BUG_ON(!path->locks[level]);
8917 ret = btrfs_inc_ref(trans, root, eb, 1);
8918 BUG_ON(ret); /* -ENOMEM */
8919 ret = btrfs_dec_ref(trans, root, eb, 0);
8920 BUG_ON(ret); /* -ENOMEM */
8921 ret = btrfs_set_disk_extent_flags(trans, fs_info, eb->start,
8923 btrfs_header_level(eb), 0);
8924 BUG_ON(ret); /* -ENOMEM */
8925 wc->flags[level] |= flag;
8929 * the block is shared by multiple trees, so it's not good to
8930 * keep the tree lock
8932 if (path->locks[level] && level > 0) {
8933 btrfs_tree_unlock_rw(eb, path->locks[level]);
8934 path->locks[level] = 0;
8940 * This is used to verify a ref exists for this root to deal with a bug where we
8941 * would have a drop_progress key that hadn't been updated properly.
8943 static int check_ref_exists(struct btrfs_trans_handle *trans,
8944 struct btrfs_root *root, u64 bytenr, u64 parent,
8947 struct btrfs_path *path;
8948 struct btrfs_extent_inline_ref *iref;
8951 path = btrfs_alloc_path();
8955 ret = lookup_extent_backref(trans, path, &iref, bytenr,
8956 root->fs_info->nodesize, parent,
8957 root->root_key.objectid, level, 0);
8958 btrfs_free_path(path);
8967 * helper to process tree block pointer.
8969 * when wc->stage == DROP_REFERENCE, this function checks
8970 * reference count of the block pointed to. if the block
8971 * is shared and we need update back refs for the subtree
8972 * rooted at the block, this function changes wc->stage to
8973 * UPDATE_BACKREF. if the block is shared and there is no
8974 * need to update back, this function drops the reference
8977 * NOTE: return value 1 means we should stop walking down.
8979 static noinline int do_walk_down(struct btrfs_trans_handle *trans,
8980 struct btrfs_root *root,
8981 struct btrfs_path *path,
8982 struct walk_control *wc, int *lookup_info)
8984 struct btrfs_fs_info *fs_info = root->fs_info;
8988 struct btrfs_key key;
8989 struct btrfs_key first_key;
8990 struct extent_buffer *next;
8991 int level = wc->level;
8994 bool need_account = false;
8996 generation = btrfs_node_ptr_generation(path->nodes[level],
8997 path->slots[level]);
8999 * if the lower level block was created before the snapshot
9000 * was created, we know there is no need to update back refs
9003 if (wc->stage == UPDATE_BACKREF &&
9004 generation <= root->root_key.offset) {
9009 bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]);
9010 btrfs_node_key_to_cpu(path->nodes[level], &first_key,
9011 path->slots[level]);
9013 next = find_extent_buffer(fs_info, bytenr);
9015 next = btrfs_find_create_tree_block(fs_info, bytenr);
9017 return PTR_ERR(next);
9019 btrfs_set_buffer_lockdep_class(root->root_key.objectid, next,
9023 btrfs_tree_lock(next);
9024 btrfs_set_lock_blocking_write(next);
9026 ret = btrfs_lookup_extent_info(trans, fs_info, bytenr, level - 1, 1,
9027 &wc->refs[level - 1],
9028 &wc->flags[level - 1]);
9032 if (unlikely(wc->refs[level - 1] == 0)) {
9033 btrfs_err(fs_info, "Missing references.");
9039 if (wc->stage == DROP_REFERENCE) {
9040 if (wc->refs[level - 1] > 1) {
9041 need_account = true;
9043 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
9046 if (!wc->update_ref ||
9047 generation <= root->root_key.offset)
9050 btrfs_node_key_to_cpu(path->nodes[level], &key,
9051 path->slots[level]);
9052 ret = btrfs_comp_cpu_keys(&key, &wc->update_progress);
9056 wc->stage = UPDATE_BACKREF;
9057 wc->shared_level = level - 1;
9061 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
9065 if (!btrfs_buffer_uptodate(next, generation, 0)) {
9066 btrfs_tree_unlock(next);
9067 free_extent_buffer(next);
9073 if (reada && level == 1)
9074 reada_walk_down(trans, root, wc, path);
9075 next = read_tree_block(fs_info, bytenr, generation, level - 1,
9078 return PTR_ERR(next);
9079 } else if (!extent_buffer_uptodate(next)) {
9080 free_extent_buffer(next);
9083 btrfs_tree_lock(next);
9084 btrfs_set_lock_blocking_write(next);
9088 ASSERT(level == btrfs_header_level(next));
9089 if (level != btrfs_header_level(next)) {
9090 btrfs_err(root->fs_info, "mismatched level");
9094 path->nodes[level] = next;
9095 path->slots[level] = 0;
9096 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
9102 wc->refs[level - 1] = 0;
9103 wc->flags[level - 1] = 0;
9104 if (wc->stage == DROP_REFERENCE) {
9105 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
9106 parent = path->nodes[level]->start;
9108 ASSERT(root->root_key.objectid ==
9109 btrfs_header_owner(path->nodes[level]));
9110 if (root->root_key.objectid !=
9111 btrfs_header_owner(path->nodes[level])) {
9112 btrfs_err(root->fs_info,
9113 "mismatched block owner");
9121 * If we had a drop_progress we need to verify the refs are set
9122 * as expected. If we find our ref then we know that from here
9123 * on out everything should be correct, and we can clear the
9126 if (wc->restarted) {
9127 ret = check_ref_exists(trans, root, bytenr, parent,
9138 * Reloc tree doesn't contribute to qgroup numbers, and we have
9139 * already accounted them at merge time (replace_path),
9140 * thus we could skip expensive subtree trace here.
9142 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID &&
9144 ret = btrfs_qgroup_trace_subtree(trans, next,
9145 generation, level - 1);
9147 btrfs_err_rl(fs_info,
9148 "Error %d accounting shared subtree. Quota is out of sync, rescan required.",
9154 * We need to update the next key in our walk control so we can
9155 * update the drop_progress key accordingly. We don't care if
9156 * find_next_key doesn't find a key because that means we're at
9157 * the end and are going to clean up now.
9159 wc->drop_level = level;
9160 find_next_key(path, level, &wc->drop_progress);
9162 ret = btrfs_free_extent(trans, root, bytenr, fs_info->nodesize,
9163 parent, root->root_key.objectid,
9173 btrfs_tree_unlock(next);
9174 free_extent_buffer(next);
9180 * helper to process tree block while walking up the tree.
9182 * when wc->stage == DROP_REFERENCE, this function drops
9183 * reference count on the block.
9185 * when wc->stage == UPDATE_BACKREF, this function changes
9186 * wc->stage back to DROP_REFERENCE if we changed wc->stage
9187 * to UPDATE_BACKREF previously while processing the block.
9189 * NOTE: return value 1 means we should stop walking up.
9191 static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
9192 struct btrfs_root *root,
9193 struct btrfs_path *path,
9194 struct walk_control *wc)
9196 struct btrfs_fs_info *fs_info = root->fs_info;
9198 int level = wc->level;
9199 struct extent_buffer *eb = path->nodes[level];
9202 if (wc->stage == UPDATE_BACKREF) {
9203 BUG_ON(wc->shared_level < level);
9204 if (level < wc->shared_level)
9207 ret = find_next_key(path, level + 1, &wc->update_progress);
9211 wc->stage = DROP_REFERENCE;
9212 wc->shared_level = -1;
9213 path->slots[level] = 0;
9216 * check reference count again if the block isn't locked.
9217 * we should start walking down the tree again if reference
9220 if (!path->locks[level]) {
9222 btrfs_tree_lock(eb);
9223 btrfs_set_lock_blocking_write(eb);
9224 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
9226 ret = btrfs_lookup_extent_info(trans, fs_info,
9227 eb->start, level, 1,
9231 btrfs_tree_unlock_rw(eb, path->locks[level]);
9232 path->locks[level] = 0;
9235 BUG_ON(wc->refs[level] == 0);
9236 if (wc->refs[level] == 1) {
9237 btrfs_tree_unlock_rw(eb, path->locks[level]);
9238 path->locks[level] = 0;
9244 /* wc->stage == DROP_REFERENCE */
9245 BUG_ON(wc->refs[level] > 1 && !path->locks[level]);
9247 if (wc->refs[level] == 1) {
9249 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
9250 ret = btrfs_dec_ref(trans, root, eb, 1);
9252 ret = btrfs_dec_ref(trans, root, eb, 0);
9253 BUG_ON(ret); /* -ENOMEM */
9254 ret = btrfs_qgroup_trace_leaf_items(trans, eb);
9256 btrfs_err_rl(fs_info,
9257 "error %d accounting leaf items. Quota is out of sync, rescan required.",
9261 /* make block locked assertion in clean_tree_block happy */
9262 if (!path->locks[level] &&
9263 btrfs_header_generation(eb) == trans->transid) {
9264 btrfs_tree_lock(eb);
9265 btrfs_set_lock_blocking_write(eb);
9266 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
9268 clean_tree_block(fs_info, eb);
9271 if (eb == root->node) {
9272 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
9274 else if (root->root_key.objectid != btrfs_header_owner(eb))
9275 goto owner_mismatch;
9277 if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
9278 parent = path->nodes[level + 1]->start;
9279 else if (root->root_key.objectid !=
9280 btrfs_header_owner(path->nodes[level + 1]))
9281 goto owner_mismatch;
9284 btrfs_free_tree_block(trans, root, eb, parent, wc->refs[level] == 1);
9286 wc->refs[level] = 0;
9287 wc->flags[level] = 0;
9291 btrfs_err_rl(fs_info, "unexpected tree owner, have %llu expect %llu",
9292 btrfs_header_owner(eb), root->root_key.objectid);
9296 static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
9297 struct btrfs_root *root,
9298 struct btrfs_path *path,
9299 struct walk_control *wc)
9301 int level = wc->level;
9302 int lookup_info = 1;
9305 while (level >= 0) {
9306 ret = walk_down_proc(trans, root, path, wc, lookup_info);
9313 if (path->slots[level] >=
9314 btrfs_header_nritems(path->nodes[level]))
9317 ret = do_walk_down(trans, root, path, wc, &lookup_info);
9319 path->slots[level]++;
9328 static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
9329 struct btrfs_root *root,
9330 struct btrfs_path *path,
9331 struct walk_control *wc, int max_level)
9333 int level = wc->level;
9336 path->slots[level] = btrfs_header_nritems(path->nodes[level]);
9337 while (level < max_level && path->nodes[level]) {
9339 if (path->slots[level] + 1 <
9340 btrfs_header_nritems(path->nodes[level])) {
9341 path->slots[level]++;
9344 ret = walk_up_proc(trans, root, path, wc);
9350 if (path->locks[level]) {
9351 btrfs_tree_unlock_rw(path->nodes[level],
9352 path->locks[level]);
9353 path->locks[level] = 0;
9355 free_extent_buffer(path->nodes[level]);
9356 path->nodes[level] = NULL;
9364 * drop a subvolume tree.
9366 * this function traverses the tree freeing any blocks that only
9367 * referenced by the tree.
9369 * when a shared tree block is found. this function decreases its
9370 * reference count by one. if update_ref is true, this function
9371 * also make sure backrefs for the shared block and all lower level
9372 * blocks are properly updated.
9374 * If called with for_reloc == 0, may exit early with -EAGAIN
9376 int btrfs_drop_snapshot(struct btrfs_root *root,
9377 struct btrfs_block_rsv *block_rsv, int update_ref,
9380 struct btrfs_fs_info *fs_info = root->fs_info;
9381 struct btrfs_path *path;
9382 struct btrfs_trans_handle *trans;
9383 struct btrfs_root *tree_root = fs_info->tree_root;
9384 struct btrfs_root_item *root_item = &root->root_item;
9385 struct walk_control *wc;
9386 struct btrfs_key key;
9390 bool root_dropped = false;
9392 btrfs_debug(fs_info, "Drop subvolume %llu", root->root_key.objectid);
9394 path = btrfs_alloc_path();
9400 wc = kzalloc(sizeof(*wc), GFP_NOFS);
9402 btrfs_free_path(path);
9407 trans = btrfs_start_transaction(tree_root, 0);
9408 if (IS_ERR(trans)) {
9409 err = PTR_ERR(trans);
9413 err = btrfs_run_delayed_items(trans);
9418 trans->block_rsv = block_rsv;
9421 * This will help us catch people modifying the fs tree while we're
9422 * dropping it. It is unsafe to mess with the fs tree while it's being
9423 * dropped as we unlock the root node and parent nodes as we walk down
9424 * the tree, assuming nothing will change. If something does change
9425 * then we'll have stale information and drop references to blocks we've
9428 set_bit(BTRFS_ROOT_DELETING, &root->state);
9429 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
9430 level = btrfs_header_level(root->node);
9431 path->nodes[level] = btrfs_lock_root_node(root);
9432 btrfs_set_lock_blocking_write(path->nodes[level]);
9433 path->slots[level] = 0;
9434 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
9435 memset(&wc->update_progress, 0,
9436 sizeof(wc->update_progress));
9438 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
9439 memcpy(&wc->update_progress, &key,
9440 sizeof(wc->update_progress));
9442 level = root_item->drop_level;
9444 path->lowest_level = level;
9445 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
9446 path->lowest_level = 0;
9454 * unlock our path, this is safe because only this
9455 * function is allowed to delete this snapshot
9457 btrfs_unlock_up_safe(path, 0);
9459 level = btrfs_header_level(root->node);
9461 btrfs_tree_lock(path->nodes[level]);
9462 btrfs_set_lock_blocking_write(path->nodes[level]);
9463 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
9465 ret = btrfs_lookup_extent_info(trans, fs_info,
9466 path->nodes[level]->start,
9467 level, 1, &wc->refs[level],
9473 BUG_ON(wc->refs[level] == 0);
9475 if (level == root_item->drop_level)
9478 btrfs_tree_unlock(path->nodes[level]);
9479 path->locks[level] = 0;
9480 WARN_ON(wc->refs[level] != 1);
9485 wc->restarted = test_bit(BTRFS_ROOT_DEAD_TREE, &root->state);
9487 wc->shared_level = -1;
9488 wc->stage = DROP_REFERENCE;
9489 wc->update_ref = update_ref;
9491 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(fs_info);
9495 ret = walk_down_tree(trans, root, path, wc);
9501 ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL);
9508 BUG_ON(wc->stage != DROP_REFERENCE);
9512 if (wc->stage == DROP_REFERENCE) {
9513 wc->drop_level = wc->level;
9514 btrfs_node_key_to_cpu(path->nodes[wc->drop_level],
9516 path->slots[wc->drop_level]);
9518 btrfs_cpu_key_to_disk(&root_item->drop_progress,
9519 &wc->drop_progress);
9520 root_item->drop_level = wc->drop_level;
9522 BUG_ON(wc->level == 0);
9523 if (btrfs_should_end_transaction(trans) ||
9524 (!for_reloc && btrfs_need_cleaner_sleep(fs_info))) {
9525 ret = btrfs_update_root(trans, tree_root,
9529 btrfs_abort_transaction(trans, ret);
9534 btrfs_end_transaction_throttle(trans);
9535 if (!for_reloc && btrfs_need_cleaner_sleep(fs_info)) {
9536 btrfs_debug(fs_info,
9537 "drop snapshot early exit");
9542 trans = btrfs_start_transaction(tree_root, 0);
9543 if (IS_ERR(trans)) {
9544 err = PTR_ERR(trans);
9548 trans->block_rsv = block_rsv;
9551 btrfs_release_path(path);
9555 ret = btrfs_del_root(trans, &root->root_key);
9557 btrfs_abort_transaction(trans, ret);
9562 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
9563 ret = btrfs_find_root(tree_root, &root->root_key, path,
9566 btrfs_abort_transaction(trans, ret);
9569 } else if (ret > 0) {
9570 /* if we fail to delete the orphan item this time
9571 * around, it'll get picked up the next time.
9573 * The most common failure here is just -ENOENT.
9575 btrfs_del_orphan_item(trans, tree_root,
9576 root->root_key.objectid);
9580 if (test_bit(BTRFS_ROOT_IN_RADIX, &root->state)) {
9581 btrfs_add_dropped_root(trans, root);
9583 free_extent_buffer(root->node);
9584 free_extent_buffer(root->commit_root);
9585 btrfs_put_fs_root(root);
9587 root_dropped = true;
9589 btrfs_end_transaction_throttle(trans);
9592 btrfs_free_path(path);
9595 * So if we need to stop dropping the snapshot for whatever reason we
9596 * need to make sure to add it back to the dead root list so that we
9597 * keep trying to do the work later. This also cleans up roots if we
9598 * don't have it in the radix (like when we recover after a power fail
9599 * or unmount) so we don't leak memory.
9601 if (!for_reloc && !root_dropped)
9602 btrfs_add_dead_root(root);
9603 if (err && err != -EAGAIN)
9604 btrfs_handle_fs_error(fs_info, err, NULL);
9609 * drop subtree rooted at tree block 'node'.
9611 * NOTE: this function will unlock and release tree block 'node'
9612 * only used by relocation code
9614 int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
9615 struct btrfs_root *root,
9616 struct extent_buffer *node,
9617 struct extent_buffer *parent)
9619 struct btrfs_fs_info *fs_info = root->fs_info;
9620 struct btrfs_path *path;
9621 struct walk_control *wc;
9627 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
9629 path = btrfs_alloc_path();
9633 wc = kzalloc(sizeof(*wc), GFP_NOFS);
9635 btrfs_free_path(path);
9639 btrfs_assert_tree_locked(parent);
9640 parent_level = btrfs_header_level(parent);
9641 extent_buffer_get(parent);
9642 path->nodes[parent_level] = parent;
9643 path->slots[parent_level] = btrfs_header_nritems(parent);
9645 btrfs_assert_tree_locked(node);
9646 level = btrfs_header_level(node);
9647 path->nodes[level] = node;
9648 path->slots[level] = 0;
9649 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
9651 wc->refs[parent_level] = 1;
9652 wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF;
9654 wc->shared_level = -1;
9655 wc->stage = DROP_REFERENCE;
9658 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(fs_info);
9661 wret = walk_down_tree(trans, root, path, wc);
9667 wret = walk_up_tree(trans, root, path, wc, parent_level);
9675 btrfs_free_path(path);
9679 static u64 update_block_group_flags(struct btrfs_fs_info *fs_info, u64 flags)
9685 * if restripe for this chunk_type is on pick target profile and
9686 * return, otherwise do the usual balance
9688 stripped = get_restripe_target(fs_info, flags);
9690 return extended_to_chunk(stripped);
9692 num_devices = fs_info->fs_devices->rw_devices;
9694 stripped = BTRFS_BLOCK_GROUP_RAID0 |
9695 BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6 |
9696 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
9698 if (num_devices == 1) {
9699 stripped |= BTRFS_BLOCK_GROUP_DUP;
9700 stripped = flags & ~stripped;
9702 /* turn raid0 into single device chunks */
9703 if (flags & BTRFS_BLOCK_GROUP_RAID0)
9706 /* turn mirroring into duplication */
9707 if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
9708 BTRFS_BLOCK_GROUP_RAID10))
9709 return stripped | BTRFS_BLOCK_GROUP_DUP;
9711 /* they already had raid on here, just return */
9712 if (flags & stripped)
9715 stripped |= BTRFS_BLOCK_GROUP_DUP;
9716 stripped = flags & ~stripped;
9718 /* switch duplicated blocks with raid1 */
9719 if (flags & BTRFS_BLOCK_GROUP_DUP)
9720 return stripped | BTRFS_BLOCK_GROUP_RAID1;
9722 /* this is drive concat, leave it alone */
9728 static int inc_block_group_ro(struct btrfs_block_group_cache *cache, int force)
9730 struct btrfs_space_info *sinfo = cache->space_info;
9733 u64 min_allocable_bytes;
9737 * We need some metadata space and system metadata space for
9738 * allocating chunks in some corner cases until we force to set
9739 * it to be readonly.
9742 (BTRFS_BLOCK_GROUP_SYSTEM | BTRFS_BLOCK_GROUP_METADATA)) &&
9744 min_allocable_bytes = SZ_1M;
9746 min_allocable_bytes = 0;
9748 spin_lock(&sinfo->lock);
9749 spin_lock(&cache->lock);
9757 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
9758 cache->bytes_super - btrfs_block_group_used(&cache->item);
9759 sinfo_used = btrfs_space_info_used(sinfo, true);
9761 if (sinfo_used + num_bytes + min_allocable_bytes <=
9762 sinfo->total_bytes) {
9763 sinfo->bytes_readonly += num_bytes;
9765 list_add_tail(&cache->ro_list, &sinfo->ro_bgs);
9769 spin_unlock(&cache->lock);
9770 spin_unlock(&sinfo->lock);
9771 if (ret == -ENOSPC && btrfs_test_opt(cache->fs_info, ENOSPC_DEBUG)) {
9772 btrfs_info(cache->fs_info,
9773 "unable to make block group %llu ro",
9774 cache->key.objectid);
9775 btrfs_info(cache->fs_info,
9776 "sinfo_used=%llu bg_num_bytes=%llu min_allocable=%llu",
9777 sinfo_used, num_bytes, min_allocable_bytes);
9778 dump_space_info(cache->fs_info, cache->space_info, 0, 0);
9783 int btrfs_inc_block_group_ro(struct btrfs_block_group_cache *cache)
9786 struct btrfs_fs_info *fs_info = cache->fs_info;
9787 struct btrfs_trans_handle *trans;
9792 trans = btrfs_join_transaction(fs_info->extent_root);
9794 return PTR_ERR(trans);
9797 * we're not allowed to set block groups readonly after the dirty
9798 * block groups cache has started writing. If it already started,
9799 * back off and let this transaction commit
9801 mutex_lock(&fs_info->ro_block_group_mutex);
9802 if (test_bit(BTRFS_TRANS_DIRTY_BG_RUN, &trans->transaction->flags)) {
9803 u64 transid = trans->transid;
9805 mutex_unlock(&fs_info->ro_block_group_mutex);
9806 btrfs_end_transaction(trans);
9808 ret = btrfs_wait_for_commit(fs_info, transid);
9815 * if we are changing raid levels, try to allocate a corresponding
9816 * block group with the new raid level.
9818 alloc_flags = update_block_group_flags(fs_info, cache->flags);
9819 if (alloc_flags != cache->flags) {
9820 ret = do_chunk_alloc(trans, alloc_flags,
9823 * ENOSPC is allowed here, we may have enough space
9824 * already allocated at the new raid level to
9833 ret = inc_block_group_ro(cache, 0);
9836 alloc_flags = get_alloc_profile(fs_info, cache->space_info->flags);
9837 ret = do_chunk_alloc(trans, alloc_flags, CHUNK_ALLOC_FORCE);
9840 ret = inc_block_group_ro(cache, 0);
9842 if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM) {
9843 alloc_flags = update_block_group_flags(fs_info, cache->flags);
9844 mutex_lock(&fs_info->chunk_mutex);
9845 check_system_chunk(trans, alloc_flags);
9846 mutex_unlock(&fs_info->chunk_mutex);
9848 mutex_unlock(&fs_info->ro_block_group_mutex);
9850 btrfs_end_transaction(trans);
9854 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans, u64 type)
9856 u64 alloc_flags = get_alloc_profile(trans->fs_info, type);
9858 return do_chunk_alloc(trans, alloc_flags, CHUNK_ALLOC_FORCE);
9862 * helper to account the unused space of all the readonly block group in the
9863 * space_info. takes mirrors into account.
9865 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo)
9867 struct btrfs_block_group_cache *block_group;
9871 /* It's df, we don't care if it's racy */
9872 if (list_empty(&sinfo->ro_bgs))
9875 spin_lock(&sinfo->lock);
9876 list_for_each_entry(block_group, &sinfo->ro_bgs, ro_list) {
9877 spin_lock(&block_group->lock);
9879 if (!block_group->ro) {
9880 spin_unlock(&block_group->lock);
9884 factor = btrfs_bg_type_to_factor(block_group->flags);
9885 free_bytes += (block_group->key.offset -
9886 btrfs_block_group_used(&block_group->item)) *
9889 spin_unlock(&block_group->lock);
9891 spin_unlock(&sinfo->lock);
9896 void btrfs_dec_block_group_ro(struct btrfs_block_group_cache *cache)
9898 struct btrfs_space_info *sinfo = cache->space_info;
9903 spin_lock(&sinfo->lock);
9904 spin_lock(&cache->lock);
9906 num_bytes = cache->key.offset - cache->reserved -
9907 cache->pinned - cache->bytes_super -
9908 btrfs_block_group_used(&cache->item);
9909 sinfo->bytes_readonly -= num_bytes;
9910 list_del_init(&cache->ro_list);
9912 spin_unlock(&cache->lock);
9913 spin_unlock(&sinfo->lock);
9917 * Checks to see if it's even possible to relocate this block group.
9919 * @return - -1 if it's not a good idea to relocate this block group, 0 if its
9920 * ok to go ahead and try.
9922 int btrfs_can_relocate(struct btrfs_fs_info *fs_info, u64 bytenr)
9924 struct btrfs_root *root = fs_info->extent_root;
9925 struct btrfs_block_group_cache *block_group;
9926 struct btrfs_space_info *space_info;
9927 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
9928 struct btrfs_device *device;
9929 struct btrfs_trans_handle *trans;
9939 debug = btrfs_test_opt(fs_info, ENOSPC_DEBUG);
9941 block_group = btrfs_lookup_block_group(fs_info, bytenr);
9943 /* odd, couldn't find the block group, leave it alone */
9947 "can't find block group for bytenr %llu",
9952 min_free = btrfs_block_group_used(&block_group->item);
9954 /* no bytes used, we're good */
9958 space_info = block_group->space_info;
9959 spin_lock(&space_info->lock);
9961 full = space_info->full;
9964 * if this is the last block group we have in this space, we can't
9965 * relocate it unless we're able to allocate a new chunk below.
9967 * Otherwise, we need to make sure we have room in the space to handle
9968 * all of the extents from this block group. If we can, we're good
9970 if ((space_info->total_bytes != block_group->key.offset) &&
9971 (btrfs_space_info_used(space_info, false) + min_free <
9972 space_info->total_bytes)) {
9973 spin_unlock(&space_info->lock);
9976 spin_unlock(&space_info->lock);
9979 * ok we don't have enough space, but maybe we have free space on our
9980 * devices to allocate new chunks for relocation, so loop through our
9981 * alloc devices and guess if we have enough space. if this block
9982 * group is going to be restriped, run checks against the target
9983 * profile instead of the current one.
9995 target = get_restripe_target(fs_info, block_group->flags);
9997 index = btrfs_bg_flags_to_raid_index(extended_to_chunk(target));
10000 * this is just a balance, so if we were marked as full
10001 * we know there is no space for a new chunk
10005 btrfs_warn(fs_info,
10006 "no space to alloc new chunk for block group %llu",
10007 block_group->key.objectid);
10011 index = btrfs_bg_flags_to_raid_index(block_group->flags);
10014 if (index == BTRFS_RAID_RAID10) {
10018 } else if (index == BTRFS_RAID_RAID1) {
10020 } else if (index == BTRFS_RAID_DUP) {
10021 /* Multiply by 2 */
10023 } else if (index == BTRFS_RAID_RAID0) {
10024 dev_min = fs_devices->rw_devices;
10025 min_free = div64_u64(min_free, dev_min);
10028 /* We need to do this so that we can look at pending chunks */
10029 trans = btrfs_join_transaction(root);
10030 if (IS_ERR(trans)) {
10031 ret = PTR_ERR(trans);
10035 mutex_lock(&fs_info->chunk_mutex);
10036 list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
10040 * check to make sure we can actually find a chunk with enough
10041 * space to fit our block group in.
10043 if (device->total_bytes > device->bytes_used + min_free &&
10044 !test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
10045 ret = find_free_dev_extent(trans, device, min_free,
10046 &dev_offset, NULL);
10050 if (dev_nr >= dev_min)
10056 if (debug && ret == -1)
10057 btrfs_warn(fs_info,
10058 "no space to allocate a new chunk for block group %llu",
10059 block_group->key.objectid);
10060 mutex_unlock(&fs_info->chunk_mutex);
10061 btrfs_end_transaction(trans);
10063 btrfs_put_block_group(block_group);
10067 static int find_first_block_group(struct btrfs_fs_info *fs_info,
10068 struct btrfs_path *path,
10069 struct btrfs_key *key)
10071 struct btrfs_root *root = fs_info->extent_root;
10073 struct btrfs_key found_key;
10074 struct extent_buffer *leaf;
10075 struct btrfs_block_group_item bg;
10079 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
10084 slot = path->slots[0];
10085 leaf = path->nodes[0];
10086 if (slot >= btrfs_header_nritems(leaf)) {
10087 ret = btrfs_next_leaf(root, path);
10094 btrfs_item_key_to_cpu(leaf, &found_key, slot);
10096 if (found_key.objectid >= key->objectid &&
10097 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
10098 struct extent_map_tree *em_tree;
10099 struct extent_map *em;
10101 em_tree = &root->fs_info->mapping_tree.map_tree;
10102 read_lock(&em_tree->lock);
10103 em = lookup_extent_mapping(em_tree, found_key.objectid,
10105 read_unlock(&em_tree->lock);
10108 "logical %llu len %llu found bg but no related chunk",
10109 found_key.objectid, found_key.offset);
10111 } else if (em->start != found_key.objectid ||
10112 em->len != found_key.offset) {
10114 "block group %llu len %llu mismatch with chunk %llu len %llu",
10115 found_key.objectid, found_key.offset,
10116 em->start, em->len);
10119 read_extent_buffer(leaf, &bg,
10120 btrfs_item_ptr_offset(leaf, slot),
10122 flags = btrfs_block_group_flags(&bg) &
10123 BTRFS_BLOCK_GROUP_TYPE_MASK;
10125 if (flags != (em->map_lookup->type &
10126 BTRFS_BLOCK_GROUP_TYPE_MASK)) {
10128 "block group %llu len %llu type flags 0x%llx mismatch with chunk type flags 0x%llx",
10129 found_key.objectid,
10130 found_key.offset, flags,
10131 (BTRFS_BLOCK_GROUP_TYPE_MASK &
10132 em->map_lookup->type));
10138 free_extent_map(em);
10147 void btrfs_put_block_group_cache(struct btrfs_fs_info *info)
10149 struct btrfs_block_group_cache *block_group;
10153 struct inode *inode;
10155 block_group = btrfs_lookup_first_block_group(info, last);
10156 while (block_group) {
10157 wait_block_group_cache_done(block_group);
10158 spin_lock(&block_group->lock);
10159 if (block_group->iref)
10161 spin_unlock(&block_group->lock);
10162 block_group = next_block_group(info, block_group);
10164 if (!block_group) {
10171 inode = block_group->inode;
10172 block_group->iref = 0;
10173 block_group->inode = NULL;
10174 spin_unlock(&block_group->lock);
10175 ASSERT(block_group->io_ctl.inode == NULL);
10177 last = block_group->key.objectid + block_group->key.offset;
10178 btrfs_put_block_group(block_group);
10183 * Must be called only after stopping all workers, since we could have block
10184 * group caching kthreads running, and therefore they could race with us if we
10185 * freed the block groups before stopping them.
10187 int btrfs_free_block_groups(struct btrfs_fs_info *info)
10189 struct btrfs_block_group_cache *block_group;
10190 struct btrfs_space_info *space_info;
10191 struct btrfs_caching_control *caching_ctl;
10194 down_write(&info->commit_root_sem);
10195 while (!list_empty(&info->caching_block_groups)) {
10196 caching_ctl = list_entry(info->caching_block_groups.next,
10197 struct btrfs_caching_control, list);
10198 list_del(&caching_ctl->list);
10199 put_caching_control(caching_ctl);
10201 up_write(&info->commit_root_sem);
10203 spin_lock(&info->unused_bgs_lock);
10204 while (!list_empty(&info->unused_bgs)) {
10205 block_group = list_first_entry(&info->unused_bgs,
10206 struct btrfs_block_group_cache,
10208 list_del_init(&block_group->bg_list);
10209 btrfs_put_block_group(block_group);
10211 spin_unlock(&info->unused_bgs_lock);
10213 spin_lock(&info->block_group_cache_lock);
10214 while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
10215 block_group = rb_entry(n, struct btrfs_block_group_cache,
10217 rb_erase(&block_group->cache_node,
10218 &info->block_group_cache_tree);
10219 RB_CLEAR_NODE(&block_group->cache_node);
10220 spin_unlock(&info->block_group_cache_lock);
10222 down_write(&block_group->space_info->groups_sem);
10223 list_del(&block_group->list);
10224 up_write(&block_group->space_info->groups_sem);
10227 * We haven't cached this block group, which means we could
10228 * possibly have excluded extents on this block group.
10230 if (block_group->cached == BTRFS_CACHE_NO ||
10231 block_group->cached == BTRFS_CACHE_ERROR)
10232 free_excluded_extents(block_group);
10234 btrfs_remove_free_space_cache(block_group);
10235 ASSERT(block_group->cached != BTRFS_CACHE_STARTED);
10236 ASSERT(list_empty(&block_group->dirty_list));
10237 ASSERT(list_empty(&block_group->io_list));
10238 ASSERT(list_empty(&block_group->bg_list));
10239 ASSERT(atomic_read(&block_group->count) == 1);
10240 btrfs_put_block_group(block_group);
10242 spin_lock(&info->block_group_cache_lock);
10244 spin_unlock(&info->block_group_cache_lock);
10246 /* now that all the block groups are freed, go through and
10247 * free all the space_info structs. This is only called during
10248 * the final stages of unmount, and so we know nobody is
10249 * using them. We call synchronize_rcu() once before we start,
10250 * just to be on the safe side.
10254 release_global_block_rsv(info);
10256 while (!list_empty(&info->space_info)) {
10259 space_info = list_entry(info->space_info.next,
10260 struct btrfs_space_info,
10264 * Do not hide this behind enospc_debug, this is actually
10265 * important and indicates a real bug if this happens.
10267 if (WARN_ON(space_info->bytes_pinned > 0 ||
10268 space_info->bytes_reserved > 0 ||
10269 space_info->bytes_may_use > 0))
10270 dump_space_info(info, space_info, 0, 0);
10271 list_del(&space_info->list);
10272 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
10273 struct kobject *kobj;
10274 kobj = space_info->block_group_kobjs[i];
10275 space_info->block_group_kobjs[i] = NULL;
10281 kobject_del(&space_info->kobj);
10282 kobject_put(&space_info->kobj);
10287 /* link_block_group will queue up kobjects to add when we're reclaim-safe */
10288 void btrfs_add_raid_kobjects(struct btrfs_fs_info *fs_info)
10290 struct btrfs_space_info *space_info;
10291 struct raid_kobject *rkobj;
10296 spin_lock(&fs_info->pending_raid_kobjs_lock);
10297 list_splice_init(&fs_info->pending_raid_kobjs, &list);
10298 spin_unlock(&fs_info->pending_raid_kobjs_lock);
10300 list_for_each_entry(rkobj, &list, list) {
10301 space_info = __find_space_info(fs_info, rkobj->flags);
10302 index = btrfs_bg_flags_to_raid_index(rkobj->flags);
10304 ret = kobject_add(&rkobj->kobj, &space_info->kobj,
10305 "%s", get_raid_name(index));
10307 kobject_put(&rkobj->kobj);
10312 btrfs_warn(fs_info,
10313 "failed to add kobject for block cache, ignoring");
10316 static void link_block_group(struct btrfs_block_group_cache *cache)
10318 struct btrfs_space_info *space_info = cache->space_info;
10319 struct btrfs_fs_info *fs_info = cache->fs_info;
10320 int index = btrfs_bg_flags_to_raid_index(cache->flags);
10321 bool first = false;
10323 down_write(&space_info->groups_sem);
10324 if (list_empty(&space_info->block_groups[index]))
10326 list_add_tail(&cache->list, &space_info->block_groups[index]);
10327 up_write(&space_info->groups_sem);
10330 struct raid_kobject *rkobj = kzalloc(sizeof(*rkobj), GFP_NOFS);
10332 btrfs_warn(cache->fs_info,
10333 "couldn't alloc memory for raid level kobject");
10336 rkobj->flags = cache->flags;
10337 kobject_init(&rkobj->kobj, &btrfs_raid_ktype);
10339 spin_lock(&fs_info->pending_raid_kobjs_lock);
10340 list_add_tail(&rkobj->list, &fs_info->pending_raid_kobjs);
10341 spin_unlock(&fs_info->pending_raid_kobjs_lock);
10342 space_info->block_group_kobjs[index] = &rkobj->kobj;
10346 static struct btrfs_block_group_cache *
10347 btrfs_create_block_group_cache(struct btrfs_fs_info *fs_info,
10348 u64 start, u64 size)
10350 struct btrfs_block_group_cache *cache;
10352 cache = kzalloc(sizeof(*cache), GFP_NOFS);
10356 cache->free_space_ctl = kzalloc(sizeof(*cache->free_space_ctl),
10358 if (!cache->free_space_ctl) {
10363 cache->key.objectid = start;
10364 cache->key.offset = size;
10365 cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
10367 cache->fs_info = fs_info;
10368 cache->full_stripe_len = btrfs_full_stripe_len(fs_info, start);
10369 set_free_space_tree_thresholds(cache);
10371 atomic_set(&cache->count, 1);
10372 spin_lock_init(&cache->lock);
10373 init_rwsem(&cache->data_rwsem);
10374 INIT_LIST_HEAD(&cache->list);
10375 INIT_LIST_HEAD(&cache->cluster_list);
10376 INIT_LIST_HEAD(&cache->bg_list);
10377 INIT_LIST_HEAD(&cache->ro_list);
10378 INIT_LIST_HEAD(&cache->dirty_list);
10379 INIT_LIST_HEAD(&cache->io_list);
10380 btrfs_init_free_space_ctl(cache);
10381 atomic_set(&cache->trimming, 0);
10382 mutex_init(&cache->free_space_lock);
10383 btrfs_init_full_stripe_locks_tree(&cache->full_stripe_locks_root);
10390 * Iterate all chunks and verify that each of them has the corresponding block
10393 static int check_chunk_block_group_mappings(struct btrfs_fs_info *fs_info)
10395 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
10396 struct extent_map *em;
10397 struct btrfs_block_group_cache *bg;
10402 read_lock(&map_tree->map_tree.lock);
10404 * lookup_extent_mapping will return the first extent map
10405 * intersecting the range, so setting @len to 1 is enough to
10406 * get the first chunk.
10408 em = lookup_extent_mapping(&map_tree->map_tree, start, 1);
10409 read_unlock(&map_tree->map_tree.lock);
10413 bg = btrfs_lookup_block_group(fs_info, em->start);
10416 "chunk start=%llu len=%llu doesn't have corresponding block group",
10417 em->start, em->len);
10419 free_extent_map(em);
10422 if (bg->key.objectid != em->start ||
10423 bg->key.offset != em->len ||
10424 (bg->flags & BTRFS_BLOCK_GROUP_TYPE_MASK) !=
10425 (em->map_lookup->type & BTRFS_BLOCK_GROUP_TYPE_MASK)) {
10427 "chunk start=%llu len=%llu flags=0x%llx doesn't match block group start=%llu len=%llu flags=0x%llx",
10428 em->start, em->len,
10429 em->map_lookup->type & BTRFS_BLOCK_GROUP_TYPE_MASK,
10430 bg->key.objectid, bg->key.offset,
10431 bg->flags & BTRFS_BLOCK_GROUP_TYPE_MASK);
10433 free_extent_map(em);
10434 btrfs_put_block_group(bg);
10437 start = em->start + em->len;
10438 free_extent_map(em);
10439 btrfs_put_block_group(bg);
10444 int btrfs_read_block_groups(struct btrfs_fs_info *info)
10446 struct btrfs_path *path;
10448 struct btrfs_block_group_cache *cache;
10449 struct btrfs_space_info *space_info;
10450 struct btrfs_key key;
10451 struct btrfs_key found_key;
10452 struct extent_buffer *leaf;
10453 int need_clear = 0;
10458 feature = btrfs_super_incompat_flags(info->super_copy);
10459 mixed = !!(feature & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS);
10463 key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
10464 path = btrfs_alloc_path();
10467 path->reada = READA_FORWARD;
10469 cache_gen = btrfs_super_cache_generation(info->super_copy);
10470 if (btrfs_test_opt(info, SPACE_CACHE) &&
10471 btrfs_super_generation(info->super_copy) != cache_gen)
10473 if (btrfs_test_opt(info, CLEAR_CACHE))
10477 ret = find_first_block_group(info, path, &key);
10483 leaf = path->nodes[0];
10484 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
10486 cache = btrfs_create_block_group_cache(info, found_key.objectid,
10495 * When we mount with old space cache, we need to
10496 * set BTRFS_DC_CLEAR and set dirty flag.
10498 * a) Setting 'BTRFS_DC_CLEAR' makes sure that we
10499 * truncate the old free space cache inode and
10501 * b) Setting 'dirty flag' makes sure that we flush
10502 * the new space cache info onto disk.
10504 if (btrfs_test_opt(info, SPACE_CACHE))
10505 cache->disk_cache_state = BTRFS_DC_CLEAR;
10508 read_extent_buffer(leaf, &cache->item,
10509 btrfs_item_ptr_offset(leaf, path->slots[0]),
10510 sizeof(cache->item));
10511 cache->flags = btrfs_block_group_flags(&cache->item);
10513 ((cache->flags & BTRFS_BLOCK_GROUP_METADATA) &&
10514 (cache->flags & BTRFS_BLOCK_GROUP_DATA))) {
10516 "bg %llu is a mixed block group but filesystem hasn't enabled mixed block groups",
10517 cache->key.objectid);
10522 key.objectid = found_key.objectid + found_key.offset;
10523 btrfs_release_path(path);
10526 * We need to exclude the super stripes now so that the space
10527 * info has super bytes accounted for, otherwise we'll think
10528 * we have more space than we actually do.
10530 ret = exclude_super_stripes(cache);
10533 * We may have excluded something, so call this just in
10536 free_excluded_extents(cache);
10537 btrfs_put_block_group(cache);
10542 * check for two cases, either we are full, and therefore
10543 * don't need to bother with the caching work since we won't
10544 * find any space, or we are empty, and we can just add all
10545 * the space in and be done with it. This saves us _a_lot_ of
10546 * time, particularly in the full case.
10548 if (found_key.offset == btrfs_block_group_used(&cache->item)) {
10549 cache->last_byte_to_unpin = (u64)-1;
10550 cache->cached = BTRFS_CACHE_FINISHED;
10551 free_excluded_extents(cache);
10552 } else if (btrfs_block_group_used(&cache->item) == 0) {
10553 cache->last_byte_to_unpin = (u64)-1;
10554 cache->cached = BTRFS_CACHE_FINISHED;
10555 add_new_free_space(cache, found_key.objectid,
10556 found_key.objectid +
10558 free_excluded_extents(cache);
10561 ret = btrfs_add_block_group_cache(info, cache);
10563 btrfs_remove_free_space_cache(cache);
10564 btrfs_put_block_group(cache);
10568 trace_btrfs_add_block_group(info, cache, 0);
10569 update_space_info(info, cache->flags, found_key.offset,
10570 btrfs_block_group_used(&cache->item),
10571 cache->bytes_super, &space_info);
10573 cache->space_info = space_info;
10575 link_block_group(cache);
10577 set_avail_alloc_bits(info, cache->flags);
10578 if (btrfs_chunk_readonly(info, cache->key.objectid)) {
10579 inc_block_group_ro(cache, 1);
10580 } else if (btrfs_block_group_used(&cache->item) == 0) {
10581 ASSERT(list_empty(&cache->bg_list));
10582 btrfs_mark_bg_unused(cache);
10586 list_for_each_entry_rcu(space_info, &info->space_info, list) {
10587 if (!(get_alloc_profile(info, space_info->flags) &
10588 (BTRFS_BLOCK_GROUP_RAID10 |
10589 BTRFS_BLOCK_GROUP_RAID1 |
10590 BTRFS_BLOCK_GROUP_RAID5 |
10591 BTRFS_BLOCK_GROUP_RAID6 |
10592 BTRFS_BLOCK_GROUP_DUP)))
10595 * avoid allocating from un-mirrored block group if there are
10596 * mirrored block groups.
10598 list_for_each_entry(cache,
10599 &space_info->block_groups[BTRFS_RAID_RAID0],
10601 inc_block_group_ro(cache, 1);
10602 list_for_each_entry(cache,
10603 &space_info->block_groups[BTRFS_RAID_SINGLE],
10605 inc_block_group_ro(cache, 1);
10608 btrfs_add_raid_kobjects(info);
10609 init_global_block_rsv(info);
10610 ret = check_chunk_block_group_mappings(info);
10612 btrfs_free_path(path);
10616 void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans)
10618 struct btrfs_fs_info *fs_info = trans->fs_info;
10619 struct btrfs_block_group_cache *block_group;
10620 struct btrfs_root *extent_root = fs_info->extent_root;
10621 struct btrfs_block_group_item item;
10622 struct btrfs_key key;
10625 if (!trans->can_flush_pending_bgs)
10628 while (!list_empty(&trans->new_bgs)) {
10629 block_group = list_first_entry(&trans->new_bgs,
10630 struct btrfs_block_group_cache,
10635 spin_lock(&block_group->lock);
10636 memcpy(&item, &block_group->item, sizeof(item));
10637 memcpy(&key, &block_group->key, sizeof(key));
10638 spin_unlock(&block_group->lock);
10640 ret = btrfs_insert_item(trans, extent_root, &key, &item,
10643 btrfs_abort_transaction(trans, ret);
10644 ret = btrfs_finish_chunk_alloc(trans, key.objectid, key.offset);
10646 btrfs_abort_transaction(trans, ret);
10647 add_block_group_free_space(trans, block_group);
10648 /* already aborted the transaction if it failed. */
10650 btrfs_delayed_refs_rsv_release(fs_info, 1);
10651 list_del_init(&block_group->bg_list);
10653 btrfs_trans_release_chunk_metadata(trans);
10656 int btrfs_make_block_group(struct btrfs_trans_handle *trans, u64 bytes_used,
10657 u64 type, u64 chunk_offset, u64 size)
10659 struct btrfs_fs_info *fs_info = trans->fs_info;
10660 struct btrfs_block_group_cache *cache;
10663 btrfs_set_log_full_commit(fs_info, trans);
10665 cache = btrfs_create_block_group_cache(fs_info, chunk_offset, size);
10669 btrfs_set_block_group_used(&cache->item, bytes_used);
10670 btrfs_set_block_group_chunk_objectid(&cache->item,
10671 BTRFS_FIRST_CHUNK_TREE_OBJECTID);
10672 btrfs_set_block_group_flags(&cache->item, type);
10674 cache->flags = type;
10675 cache->last_byte_to_unpin = (u64)-1;
10676 cache->cached = BTRFS_CACHE_FINISHED;
10677 cache->needs_free_space = 1;
10678 ret = exclude_super_stripes(cache);
10681 * We may have excluded something, so call this just in
10684 free_excluded_extents(cache);
10685 btrfs_put_block_group(cache);
10689 add_new_free_space(cache, chunk_offset, chunk_offset + size);
10691 free_excluded_extents(cache);
10693 #ifdef CONFIG_BTRFS_DEBUG
10694 if (btrfs_should_fragment_free_space(cache)) {
10695 u64 new_bytes_used = size - bytes_used;
10697 bytes_used += new_bytes_used >> 1;
10698 fragment_free_space(cache);
10702 * Ensure the corresponding space_info object is created and
10703 * assigned to our block group. We want our bg to be added to the rbtree
10704 * with its ->space_info set.
10706 cache->space_info = __find_space_info(fs_info, cache->flags);
10707 ASSERT(cache->space_info);
10709 ret = btrfs_add_block_group_cache(fs_info, cache);
10711 btrfs_remove_free_space_cache(cache);
10712 btrfs_put_block_group(cache);
10717 * Now that our block group has its ->space_info set and is inserted in
10718 * the rbtree, update the space info's counters.
10720 trace_btrfs_add_block_group(fs_info, cache, 1);
10721 update_space_info(fs_info, cache->flags, size, bytes_used,
10722 cache->bytes_super, &cache->space_info);
10723 update_global_block_rsv(fs_info);
10725 link_block_group(cache);
10727 list_add_tail(&cache->bg_list, &trans->new_bgs);
10728 trans->delayed_ref_updates++;
10729 btrfs_update_delayed_refs_rsv(trans);
10731 set_avail_alloc_bits(fs_info, type);
10735 static void clear_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
10737 u64 extra_flags = chunk_to_extended(flags) &
10738 BTRFS_EXTENDED_PROFILE_MASK;
10740 write_seqlock(&fs_info->profiles_lock);
10741 if (flags & BTRFS_BLOCK_GROUP_DATA)
10742 fs_info->avail_data_alloc_bits &= ~extra_flags;
10743 if (flags & BTRFS_BLOCK_GROUP_METADATA)
10744 fs_info->avail_metadata_alloc_bits &= ~extra_flags;
10745 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
10746 fs_info->avail_system_alloc_bits &= ~extra_flags;
10747 write_sequnlock(&fs_info->profiles_lock);
10750 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
10751 u64 group_start, struct extent_map *em)
10753 struct btrfs_fs_info *fs_info = trans->fs_info;
10754 struct btrfs_root *root = fs_info->extent_root;
10755 struct btrfs_path *path;
10756 struct btrfs_block_group_cache *block_group;
10757 struct btrfs_free_cluster *cluster;
10758 struct btrfs_root *tree_root = fs_info->tree_root;
10759 struct btrfs_key key;
10760 struct inode *inode;
10761 struct kobject *kobj = NULL;
10765 struct btrfs_caching_control *caching_ctl = NULL;
10767 bool remove_rsv = false;
10769 block_group = btrfs_lookup_block_group(fs_info, group_start);
10770 BUG_ON(!block_group);
10771 BUG_ON(!block_group->ro);
10773 trace_btrfs_remove_block_group(block_group);
10775 * Free the reserved super bytes from this block group before
10778 free_excluded_extents(block_group);
10779 btrfs_free_ref_tree_range(fs_info, block_group->key.objectid,
10780 block_group->key.offset);
10782 memcpy(&key, &block_group->key, sizeof(key));
10783 index = btrfs_bg_flags_to_raid_index(block_group->flags);
10784 factor = btrfs_bg_type_to_factor(block_group->flags);
10786 /* make sure this block group isn't part of an allocation cluster */
10787 cluster = &fs_info->data_alloc_cluster;
10788 spin_lock(&cluster->refill_lock);
10789 btrfs_return_cluster_to_free_space(block_group, cluster);
10790 spin_unlock(&cluster->refill_lock);
10793 * make sure this block group isn't part of a metadata
10794 * allocation cluster
10796 cluster = &fs_info->meta_alloc_cluster;
10797 spin_lock(&cluster->refill_lock);
10798 btrfs_return_cluster_to_free_space(block_group, cluster);
10799 spin_unlock(&cluster->refill_lock);
10801 path = btrfs_alloc_path();
10808 * get the inode first so any iput calls done for the io_list
10809 * aren't the final iput (no unlinks allowed now)
10811 inode = lookup_free_space_inode(fs_info, block_group, path);
10813 mutex_lock(&trans->transaction->cache_write_mutex);
10815 * Make sure our free space cache IO is done before removing the
10818 spin_lock(&trans->transaction->dirty_bgs_lock);
10819 if (!list_empty(&block_group->io_list)) {
10820 list_del_init(&block_group->io_list);
10822 WARN_ON(!IS_ERR(inode) && inode != block_group->io_ctl.inode);
10824 spin_unlock(&trans->transaction->dirty_bgs_lock);
10825 btrfs_wait_cache_io(trans, block_group, path);
10826 btrfs_put_block_group(block_group);
10827 spin_lock(&trans->transaction->dirty_bgs_lock);
10830 if (!list_empty(&block_group->dirty_list)) {
10831 list_del_init(&block_group->dirty_list);
10833 btrfs_put_block_group(block_group);
10835 spin_unlock(&trans->transaction->dirty_bgs_lock);
10836 mutex_unlock(&trans->transaction->cache_write_mutex);
10838 if (!IS_ERR(inode)) {
10839 ret = btrfs_orphan_add(trans, BTRFS_I(inode));
10841 btrfs_add_delayed_iput(inode);
10844 clear_nlink(inode);
10845 /* One for the block groups ref */
10846 spin_lock(&block_group->lock);
10847 if (block_group->iref) {
10848 block_group->iref = 0;
10849 block_group->inode = NULL;
10850 spin_unlock(&block_group->lock);
10853 spin_unlock(&block_group->lock);
10855 /* One for our lookup ref */
10856 btrfs_add_delayed_iput(inode);
10859 key.objectid = BTRFS_FREE_SPACE_OBJECTID;
10860 key.offset = block_group->key.objectid;
10863 ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1);
10867 btrfs_release_path(path);
10869 ret = btrfs_del_item(trans, tree_root, path);
10872 btrfs_release_path(path);
10875 spin_lock(&fs_info->block_group_cache_lock);
10876 rb_erase(&block_group->cache_node,
10877 &fs_info->block_group_cache_tree);
10878 RB_CLEAR_NODE(&block_group->cache_node);
10880 if (fs_info->first_logical_byte == block_group->key.objectid)
10881 fs_info->first_logical_byte = (u64)-1;
10882 spin_unlock(&fs_info->block_group_cache_lock);
10884 down_write(&block_group->space_info->groups_sem);
10886 * we must use list_del_init so people can check to see if they
10887 * are still on the list after taking the semaphore
10889 list_del_init(&block_group->list);
10890 if (list_empty(&block_group->space_info->block_groups[index])) {
10891 kobj = block_group->space_info->block_group_kobjs[index];
10892 block_group->space_info->block_group_kobjs[index] = NULL;
10893 clear_avail_alloc_bits(fs_info, block_group->flags);
10895 up_write(&block_group->space_info->groups_sem);
10901 if (block_group->has_caching_ctl)
10902 caching_ctl = get_caching_control(block_group);
10903 if (block_group->cached == BTRFS_CACHE_STARTED)
10904 wait_block_group_cache_done(block_group);
10905 if (block_group->has_caching_ctl) {
10906 down_write(&fs_info->commit_root_sem);
10907 if (!caching_ctl) {
10908 struct btrfs_caching_control *ctl;
10910 list_for_each_entry(ctl,
10911 &fs_info->caching_block_groups, list)
10912 if (ctl->block_group == block_group) {
10914 refcount_inc(&caching_ctl->count);
10919 list_del_init(&caching_ctl->list);
10920 up_write(&fs_info->commit_root_sem);
10922 /* Once for the caching bgs list and once for us. */
10923 put_caching_control(caching_ctl);
10924 put_caching_control(caching_ctl);
10928 spin_lock(&trans->transaction->dirty_bgs_lock);
10929 WARN_ON(!list_empty(&block_group->dirty_list));
10930 WARN_ON(!list_empty(&block_group->io_list));
10931 spin_unlock(&trans->transaction->dirty_bgs_lock);
10933 btrfs_remove_free_space_cache(block_group);
10935 spin_lock(&block_group->space_info->lock);
10936 list_del_init(&block_group->ro_list);
10938 if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
10939 WARN_ON(block_group->space_info->total_bytes
10940 < block_group->key.offset);
10941 WARN_ON(block_group->space_info->bytes_readonly
10942 < block_group->key.offset);
10943 WARN_ON(block_group->space_info->disk_total
10944 < block_group->key.offset * factor);
10946 block_group->space_info->total_bytes -= block_group->key.offset;
10947 block_group->space_info->bytes_readonly -= block_group->key.offset;
10948 block_group->space_info->disk_total -= block_group->key.offset * factor;
10950 spin_unlock(&block_group->space_info->lock);
10952 memcpy(&key, &block_group->key, sizeof(key));
10954 mutex_lock(&fs_info->chunk_mutex);
10955 if (!list_empty(&em->list)) {
10956 /* We're in the transaction->pending_chunks list. */
10957 free_extent_map(em);
10959 spin_lock(&block_group->lock);
10960 block_group->removed = 1;
10962 * At this point trimming can't start on this block group, because we
10963 * removed the block group from the tree fs_info->block_group_cache_tree
10964 * so no one can't find it anymore and even if someone already got this
10965 * block group before we removed it from the rbtree, they have already
10966 * incremented block_group->trimming - if they didn't, they won't find
10967 * any free space entries because we already removed them all when we
10968 * called btrfs_remove_free_space_cache().
10970 * And we must not remove the extent map from the fs_info->mapping_tree
10971 * to prevent the same logical address range and physical device space
10972 * ranges from being reused for a new block group. This is because our
10973 * fs trim operation (btrfs_trim_fs() / btrfs_ioctl_fitrim()) is
10974 * completely transactionless, so while it is trimming a range the
10975 * currently running transaction might finish and a new one start,
10976 * allowing for new block groups to be created that can reuse the same
10977 * physical device locations unless we take this special care.
10979 * There may also be an implicit trim operation if the file system
10980 * is mounted with -odiscard. The same protections must remain
10981 * in place until the extents have been discarded completely when
10982 * the transaction commit has completed.
10984 remove_em = (atomic_read(&block_group->trimming) == 0);
10986 * Make sure a trimmer task always sees the em in the pinned_chunks list
10987 * if it sees block_group->removed == 1 (needs to lock block_group->lock
10988 * before checking block_group->removed).
10992 * Our em might be in trans->transaction->pending_chunks which
10993 * is protected by fs_info->chunk_mutex ([lock|unlock]_chunks),
10994 * and so is the fs_info->pinned_chunks list.
10996 * So at this point we must be holding the chunk_mutex to avoid
10997 * any races with chunk allocation (more specifically at
10998 * volumes.c:contains_pending_extent()), to ensure it always
10999 * sees the em, either in the pending_chunks list or in the
11000 * pinned_chunks list.
11002 list_move_tail(&em->list, &fs_info->pinned_chunks);
11004 spin_unlock(&block_group->lock);
11007 struct extent_map_tree *em_tree;
11009 em_tree = &fs_info->mapping_tree.map_tree;
11010 write_lock(&em_tree->lock);
11012 * The em might be in the pending_chunks list, so make sure the
11013 * chunk mutex is locked, since remove_extent_mapping() will
11014 * delete us from that list.
11016 remove_extent_mapping(em_tree, em);
11017 write_unlock(&em_tree->lock);
11018 /* once for the tree */
11019 free_extent_map(em);
11022 mutex_unlock(&fs_info->chunk_mutex);
11024 ret = remove_block_group_free_space(trans, block_group);
11028 btrfs_put_block_group(block_group);
11029 btrfs_put_block_group(block_group);
11031 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
11037 ret = btrfs_del_item(trans, root, path);
11040 btrfs_delayed_refs_rsv_release(fs_info, 1);
11041 btrfs_free_path(path);
11045 struct btrfs_trans_handle *
11046 btrfs_start_trans_remove_block_group(struct btrfs_fs_info *fs_info,
11047 const u64 chunk_offset)
11049 struct extent_map_tree *em_tree = &fs_info->mapping_tree.map_tree;
11050 struct extent_map *em;
11051 struct map_lookup *map;
11052 unsigned int num_items;
11054 read_lock(&em_tree->lock);
11055 em = lookup_extent_mapping(em_tree, chunk_offset, 1);
11056 read_unlock(&em_tree->lock);
11057 ASSERT(em && em->start == chunk_offset);
11060 * We need to reserve 3 + N units from the metadata space info in order
11061 * to remove a block group (done at btrfs_remove_chunk() and at
11062 * btrfs_remove_block_group()), which are used for:
11064 * 1 unit for adding the free space inode's orphan (located in the tree
11066 * 1 unit for deleting the block group item (located in the extent
11068 * 1 unit for deleting the free space item (located in tree of tree
11070 * N units for deleting N device extent items corresponding to each
11071 * stripe (located in the device tree).
11073 * In order to remove a block group we also need to reserve units in the
11074 * system space info in order to update the chunk tree (update one or
11075 * more device items and remove one chunk item), but this is done at
11076 * btrfs_remove_chunk() through a call to check_system_chunk().
11078 map = em->map_lookup;
11079 num_items = 3 + map->num_stripes;
11080 free_extent_map(em);
11082 return btrfs_start_transaction_fallback_global_rsv(fs_info->extent_root,
11087 * Process the unused_bgs list and remove any that don't have any allocated
11088 * space inside of them.
11090 void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info)
11092 struct btrfs_block_group_cache *block_group;
11093 struct btrfs_space_info *space_info;
11094 struct btrfs_trans_handle *trans;
11097 if (!test_bit(BTRFS_FS_OPEN, &fs_info->flags))
11100 spin_lock(&fs_info->unused_bgs_lock);
11101 while (!list_empty(&fs_info->unused_bgs)) {
11105 block_group = list_first_entry(&fs_info->unused_bgs,
11106 struct btrfs_block_group_cache,
11108 list_del_init(&block_group->bg_list);
11110 space_info = block_group->space_info;
11112 if (ret || btrfs_mixed_space_info(space_info)) {
11113 btrfs_put_block_group(block_group);
11116 spin_unlock(&fs_info->unused_bgs_lock);
11118 mutex_lock(&fs_info->delete_unused_bgs_mutex);
11120 /* Don't want to race with allocators so take the groups_sem */
11121 down_write(&space_info->groups_sem);
11122 spin_lock(&block_group->lock);
11123 if (block_group->reserved || block_group->pinned ||
11124 btrfs_block_group_used(&block_group->item) ||
11126 list_is_singular(&block_group->list)) {
11128 * We want to bail if we made new allocations or have
11129 * outstanding allocations in this block group. We do
11130 * the ro check in case balance is currently acting on
11131 * this block group.
11133 trace_btrfs_skip_unused_block_group(block_group);
11134 spin_unlock(&block_group->lock);
11135 up_write(&space_info->groups_sem);
11138 spin_unlock(&block_group->lock);
11140 /* We don't want to force the issue, only flip if it's ok. */
11141 ret = inc_block_group_ro(block_group, 0);
11142 up_write(&space_info->groups_sem);
11149 * Want to do this before we do anything else so we can recover
11150 * properly if we fail to join the transaction.
11152 trans = btrfs_start_trans_remove_block_group(fs_info,
11153 block_group->key.objectid);
11154 if (IS_ERR(trans)) {
11155 btrfs_dec_block_group_ro(block_group);
11156 ret = PTR_ERR(trans);
11161 * We could have pending pinned extents for this block group,
11162 * just delete them, we don't care about them anymore.
11164 start = block_group->key.objectid;
11165 end = start + block_group->key.offset - 1;
11167 * Hold the unused_bg_unpin_mutex lock to avoid racing with
11168 * btrfs_finish_extent_commit(). If we are at transaction N,
11169 * another task might be running finish_extent_commit() for the
11170 * previous transaction N - 1, and have seen a range belonging
11171 * to the block group in freed_extents[] before we were able to
11172 * clear the whole block group range from freed_extents[]. This
11173 * means that task can lookup for the block group after we
11174 * unpinned it from freed_extents[] and removed it, leading to
11175 * a BUG_ON() at btrfs_unpin_extent_range().
11177 mutex_lock(&fs_info->unused_bg_unpin_mutex);
11178 ret = clear_extent_bits(&fs_info->freed_extents[0], start, end,
11181 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
11182 btrfs_dec_block_group_ro(block_group);
11185 ret = clear_extent_bits(&fs_info->freed_extents[1], start, end,
11188 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
11189 btrfs_dec_block_group_ro(block_group);
11192 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
11194 /* Reset pinned so btrfs_put_block_group doesn't complain */
11195 spin_lock(&space_info->lock);
11196 spin_lock(&block_group->lock);
11198 update_bytes_pinned(space_info, -block_group->pinned);
11199 space_info->bytes_readonly += block_group->pinned;
11200 percpu_counter_add_batch(&space_info->total_bytes_pinned,
11201 -block_group->pinned,
11202 BTRFS_TOTAL_BYTES_PINNED_BATCH);
11203 block_group->pinned = 0;
11205 spin_unlock(&block_group->lock);
11206 spin_unlock(&space_info->lock);
11208 /* DISCARD can flip during remount */
11209 trimming = btrfs_test_opt(fs_info, DISCARD);
11211 /* Implicit trim during transaction commit. */
11213 btrfs_get_block_group_trimming(block_group);
11216 * Btrfs_remove_chunk will abort the transaction if things go
11219 ret = btrfs_remove_chunk(trans, block_group->key.objectid);
11223 btrfs_put_block_group_trimming(block_group);
11228 * If we're not mounted with -odiscard, we can just forget
11229 * about this block group. Otherwise we'll need to wait
11230 * until transaction commit to do the actual discard.
11233 spin_lock(&fs_info->unused_bgs_lock);
11235 * A concurrent scrub might have added us to the list
11236 * fs_info->unused_bgs, so use a list_move operation
11237 * to add the block group to the deleted_bgs list.
11239 list_move(&block_group->bg_list,
11240 &trans->transaction->deleted_bgs);
11241 spin_unlock(&fs_info->unused_bgs_lock);
11242 btrfs_get_block_group(block_group);
11245 btrfs_end_transaction(trans);
11247 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
11248 btrfs_put_block_group(block_group);
11249 spin_lock(&fs_info->unused_bgs_lock);
11251 spin_unlock(&fs_info->unused_bgs_lock);
11254 int btrfs_init_space_info(struct btrfs_fs_info *fs_info)
11256 struct btrfs_super_block *disk_super;
11262 disk_super = fs_info->super_copy;
11263 if (!btrfs_super_root(disk_super))
11266 features = btrfs_super_incompat_flags(disk_super);
11267 if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
11270 flags = BTRFS_BLOCK_GROUP_SYSTEM;
11271 ret = create_space_info(fs_info, flags);
11276 flags = BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA;
11277 ret = create_space_info(fs_info, flags);
11279 flags = BTRFS_BLOCK_GROUP_METADATA;
11280 ret = create_space_info(fs_info, flags);
11284 flags = BTRFS_BLOCK_GROUP_DATA;
11285 ret = create_space_info(fs_info, flags);
11291 int btrfs_error_unpin_extent_range(struct btrfs_fs_info *fs_info,
11292 u64 start, u64 end)
11294 return unpin_extent_range(fs_info, start, end, false);
11298 * It used to be that old block groups would be left around forever.
11299 * Iterating over them would be enough to trim unused space. Since we
11300 * now automatically remove them, we also need to iterate over unallocated
11303 * We don't want a transaction for this since the discard may take a
11304 * substantial amount of time. We don't require that a transaction be
11305 * running, but we do need to take a running transaction into account
11306 * to ensure that we're not discarding chunks that were released or
11307 * allocated in the current transaction.
11309 * Holding the chunks lock will prevent other threads from allocating
11310 * or releasing chunks, but it won't prevent a running transaction
11311 * from committing and releasing the memory that the pending chunks
11312 * list head uses. For that, we need to take a reference to the
11313 * transaction and hold the commit root sem. We only need to hold
11314 * it while performing the free space search since we have already
11315 * held back allocations.
11317 static int btrfs_trim_free_extents(struct btrfs_device *device,
11318 u64 minlen, u64 *trimmed)
11320 u64 start = 0, len = 0;
11325 /* Discard not supported = nothing to do. */
11326 if (!blk_queue_discard(bdev_get_queue(device->bdev)))
11329 /* Not writable = nothing to do. */
11330 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state))
11333 /* No free space = nothing to do. */
11334 if (device->total_bytes <= device->bytes_used)
11340 struct btrfs_fs_info *fs_info = device->fs_info;
11341 struct btrfs_transaction *trans;
11344 ret = mutex_lock_interruptible(&fs_info->chunk_mutex);
11348 ret = down_read_killable(&fs_info->commit_root_sem);
11350 mutex_unlock(&fs_info->chunk_mutex);
11354 spin_lock(&fs_info->trans_lock);
11355 trans = fs_info->running_transaction;
11357 refcount_inc(&trans->use_count);
11358 spin_unlock(&fs_info->trans_lock);
11361 up_read(&fs_info->commit_root_sem);
11363 ret = find_free_dev_extent_start(trans, device, minlen, start,
11366 up_read(&fs_info->commit_root_sem);
11367 btrfs_put_transaction(trans);
11371 mutex_unlock(&fs_info->chunk_mutex);
11372 if (ret == -ENOSPC)
11377 ret = btrfs_issue_discard(device->bdev, start, len, &bytes);
11378 mutex_unlock(&fs_info->chunk_mutex);
11386 if (fatal_signal_pending(current)) {
11387 ret = -ERESTARTSYS;
11398 * Trim the whole filesystem by:
11399 * 1) trimming the free space in each block group
11400 * 2) trimming the unallocated space on each device
11402 * This will also continue trimming even if a block group or device encounters
11403 * an error. The return value will be the last error, or 0 if nothing bad
11406 int btrfs_trim_fs(struct btrfs_fs_info *fs_info, struct fstrim_range *range)
11408 struct btrfs_block_group_cache *cache = NULL;
11409 struct btrfs_device *device;
11410 struct list_head *devices;
11416 u64 dev_failed = 0;
11421 cache = btrfs_lookup_first_block_group(fs_info, range->start);
11422 for (; cache; cache = next_block_group(fs_info, cache)) {
11423 if (cache->key.objectid >= (range->start + range->len)) {
11424 btrfs_put_block_group(cache);
11428 start = max(range->start, cache->key.objectid);
11429 end = min(range->start + range->len,
11430 cache->key.objectid + cache->key.offset);
11432 if (end - start >= range->minlen) {
11433 if (!block_group_cache_done(cache)) {
11434 ret = cache_block_group(cache, 0);
11440 ret = wait_block_group_cache_done(cache);
11447 ret = btrfs_trim_block_group(cache,
11453 trimmed += group_trimmed;
11463 btrfs_warn(fs_info,
11464 "failed to trim %llu block group(s), last error %d",
11465 bg_failed, bg_ret);
11466 mutex_lock(&fs_info->fs_devices->device_list_mutex);
11467 devices = &fs_info->fs_devices->devices;
11468 list_for_each_entry(device, devices, dev_list) {
11469 ret = btrfs_trim_free_extents(device, range->minlen,
11477 trimmed += group_trimmed;
11479 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
11482 btrfs_warn(fs_info,
11483 "failed to trim %llu device(s), last error %d",
11484 dev_failed, dev_ret);
11485 range->len = trimmed;
11492 * btrfs_{start,end}_write_no_snapshotting() are similar to
11493 * mnt_{want,drop}_write(), they are used to prevent some tasks from writing
11494 * data into the page cache through nocow before the subvolume is snapshoted,
11495 * but flush the data into disk after the snapshot creation, or to prevent
11496 * operations while snapshotting is ongoing and that cause the snapshot to be
11497 * inconsistent (writes followed by expanding truncates for example).
11499 void btrfs_end_write_no_snapshotting(struct btrfs_root *root)
11501 percpu_counter_dec(&root->subv_writers->counter);
11502 cond_wake_up(&root->subv_writers->wait);
11505 int btrfs_start_write_no_snapshotting(struct btrfs_root *root)
11507 if (atomic_read(&root->will_be_snapshotted))
11510 percpu_counter_inc(&root->subv_writers->counter);
11512 * Make sure counter is updated before we check for snapshot creation.
11515 if (atomic_read(&root->will_be_snapshotted)) {
11516 btrfs_end_write_no_snapshotting(root);
11522 void btrfs_wait_for_snapshot_creation(struct btrfs_root *root)
11527 ret = btrfs_start_write_no_snapshotting(root);
11530 wait_var_event(&root->will_be_snapshotted,
11531 !atomic_read(&root->will_be_snapshotted));
11535 void btrfs_mark_bg_unused(struct btrfs_block_group_cache *bg)
11537 struct btrfs_fs_info *fs_info = bg->fs_info;
11539 spin_lock(&fs_info->unused_bgs_lock);
11540 if (list_empty(&bg->bg_list)) {
11541 btrfs_get_block_group(bg);
11542 trace_btrfs_add_unused_block_group(bg);
11543 list_add_tail(&bg->bg_list, &fs_info->unused_bgs);
11545 spin_unlock(&fs_info->unused_bgs_lock);