2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
18 #include <linux/sched.h>
19 #include <linux/pagemap.h>
20 #include <linux/writeback.h>
21 #include <linux/blkdev.h>
22 #include <linux/sort.h>
23 #include <linux/rcupdate.h>
24 #include <linux/kthread.h>
25 #include <linux/slab.h>
26 #include <linux/ratelimit.h>
27 #include <linux/percpu_counter.h>
31 #include "print-tree.h"
35 #include "free-space-cache.h"
40 #undef SCRAMBLE_DELAYED_REFS
43 * control flags for do_chunk_alloc's force field
44 * CHUNK_ALLOC_NO_FORCE means to only allocate a chunk
45 * if we really need one.
47 * CHUNK_ALLOC_LIMITED means to only try and allocate one
48 * if we have very few chunks already allocated. This is
49 * used as part of the clustering code to help make sure
50 * we have a good pool of storage to cluster in, without
51 * filling the FS with empty chunks
53 * CHUNK_ALLOC_FORCE means it must try to allocate one
57 CHUNK_ALLOC_NO_FORCE = 0,
58 CHUNK_ALLOC_LIMITED = 1,
59 CHUNK_ALLOC_FORCE = 2,
63 * Control how reservations are dealt with.
65 * RESERVE_FREE - freeing a reservation.
66 * RESERVE_ALLOC - allocating space and we need to update bytes_may_use for
68 * RESERVE_ALLOC_NO_ACCOUNT - allocating space and we should not update
69 * bytes_may_use as the ENOSPC accounting is done elsewhere
74 RESERVE_ALLOC_NO_ACCOUNT = 2,
77 static int update_block_group(struct btrfs_trans_handle *trans,
78 struct btrfs_root *root, u64 bytenr,
79 u64 num_bytes, int alloc);
80 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
81 struct btrfs_root *root,
82 struct btrfs_delayed_ref_node *node, u64 parent,
83 u64 root_objectid, u64 owner_objectid,
84 u64 owner_offset, int refs_to_drop,
85 struct btrfs_delayed_extent_op *extra_op);
86 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
87 struct extent_buffer *leaf,
88 struct btrfs_extent_item *ei);
89 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
90 struct btrfs_root *root,
91 u64 parent, u64 root_objectid,
92 u64 flags, u64 owner, u64 offset,
93 struct btrfs_key *ins, int ref_mod);
94 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
95 struct btrfs_root *root,
96 u64 parent, u64 root_objectid,
97 u64 flags, struct btrfs_disk_key *key,
98 int level, struct btrfs_key *ins,
100 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
101 struct btrfs_root *extent_root, u64 flags,
103 static int find_next_key(struct btrfs_path *path, int level,
104 struct btrfs_key *key);
105 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
106 int dump_block_groups);
107 static int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache,
108 u64 num_bytes, int reserve,
110 static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
112 int btrfs_pin_extent(struct btrfs_root *root,
113 u64 bytenr, u64 num_bytes, int reserved);
116 block_group_cache_done(struct btrfs_block_group_cache *cache)
119 return cache->cached == BTRFS_CACHE_FINISHED ||
120 cache->cached == BTRFS_CACHE_ERROR;
123 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
125 return (cache->flags & bits) == bits;
128 static void btrfs_get_block_group(struct btrfs_block_group_cache *cache)
130 atomic_inc(&cache->count);
133 void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
135 if (atomic_dec_and_test(&cache->count)) {
136 WARN_ON(cache->pinned > 0);
137 WARN_ON(cache->reserved > 0);
138 kfree(cache->free_space_ctl);
144 * this adds the block group to the fs_info rb tree for the block group
147 static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
148 struct btrfs_block_group_cache *block_group)
151 struct rb_node *parent = NULL;
152 struct btrfs_block_group_cache *cache;
154 spin_lock(&info->block_group_cache_lock);
155 p = &info->block_group_cache_tree.rb_node;
159 cache = rb_entry(parent, struct btrfs_block_group_cache,
161 if (block_group->key.objectid < cache->key.objectid) {
163 } else if (block_group->key.objectid > cache->key.objectid) {
166 spin_unlock(&info->block_group_cache_lock);
171 rb_link_node(&block_group->cache_node, parent, p);
172 rb_insert_color(&block_group->cache_node,
173 &info->block_group_cache_tree);
175 if (info->first_logical_byte > block_group->key.objectid)
176 info->first_logical_byte = block_group->key.objectid;
178 spin_unlock(&info->block_group_cache_lock);
184 * This will return the block group at or after bytenr if contains is 0, else
185 * it will return the block group that contains the bytenr
187 static struct btrfs_block_group_cache *
188 block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
191 struct btrfs_block_group_cache *cache, *ret = NULL;
195 spin_lock(&info->block_group_cache_lock);
196 n = info->block_group_cache_tree.rb_node;
199 cache = rb_entry(n, struct btrfs_block_group_cache,
201 end = cache->key.objectid + cache->key.offset - 1;
202 start = cache->key.objectid;
204 if (bytenr < start) {
205 if (!contains && (!ret || start < ret->key.objectid))
208 } else if (bytenr > start) {
209 if (contains && bytenr <= end) {
220 btrfs_get_block_group(ret);
221 if (bytenr == 0 && info->first_logical_byte > ret->key.objectid)
222 info->first_logical_byte = ret->key.objectid;
224 spin_unlock(&info->block_group_cache_lock);
229 static int add_excluded_extent(struct btrfs_root *root,
230 u64 start, u64 num_bytes)
232 u64 end = start + num_bytes - 1;
233 set_extent_bits(&root->fs_info->freed_extents[0],
234 start, end, EXTENT_UPTODATE, GFP_NOFS);
235 set_extent_bits(&root->fs_info->freed_extents[1],
236 start, end, EXTENT_UPTODATE, GFP_NOFS);
240 static void free_excluded_extents(struct btrfs_root *root,
241 struct btrfs_block_group_cache *cache)
245 start = cache->key.objectid;
246 end = start + cache->key.offset - 1;
248 clear_extent_bits(&root->fs_info->freed_extents[0],
249 start, end, EXTENT_UPTODATE, GFP_NOFS);
250 clear_extent_bits(&root->fs_info->freed_extents[1],
251 start, end, EXTENT_UPTODATE, GFP_NOFS);
254 static int exclude_super_stripes(struct btrfs_root *root,
255 struct btrfs_block_group_cache *cache)
262 if (cache->key.objectid < BTRFS_SUPER_INFO_OFFSET) {
263 stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->key.objectid;
264 cache->bytes_super += stripe_len;
265 ret = add_excluded_extent(root, cache->key.objectid,
271 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
272 bytenr = btrfs_sb_offset(i);
273 ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
274 cache->key.objectid, bytenr,
275 0, &logical, &nr, &stripe_len);
282 if (logical[nr] > cache->key.objectid +
286 if (logical[nr] + stripe_len <= cache->key.objectid)
290 if (start < cache->key.objectid) {
291 start = cache->key.objectid;
292 len = (logical[nr] + stripe_len) - start;
294 len = min_t(u64, stripe_len,
295 cache->key.objectid +
296 cache->key.offset - start);
299 cache->bytes_super += len;
300 ret = add_excluded_extent(root, start, len);
312 static struct btrfs_caching_control *
313 get_caching_control(struct btrfs_block_group_cache *cache)
315 struct btrfs_caching_control *ctl;
317 spin_lock(&cache->lock);
318 if (!cache->caching_ctl) {
319 spin_unlock(&cache->lock);
323 ctl = cache->caching_ctl;
324 atomic_inc(&ctl->count);
325 spin_unlock(&cache->lock);
329 static void put_caching_control(struct btrfs_caching_control *ctl)
331 if (atomic_dec_and_test(&ctl->count))
336 * this is only called by cache_block_group, since we could have freed extents
337 * we need to check the pinned_extents for any extents that can't be used yet
338 * since their free space will be released as soon as the transaction commits.
340 static u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
341 struct btrfs_fs_info *info, u64 start, u64 end)
343 u64 extent_start, extent_end, size, total_added = 0;
346 while (start < end) {
347 ret = find_first_extent_bit(info->pinned_extents, start,
348 &extent_start, &extent_end,
349 EXTENT_DIRTY | EXTENT_UPTODATE,
354 if (extent_start <= start) {
355 start = extent_end + 1;
356 } else if (extent_start > start && extent_start < end) {
357 size = extent_start - start;
359 ret = btrfs_add_free_space(block_group, start,
361 BUG_ON(ret); /* -ENOMEM or logic error */
362 start = extent_end + 1;
371 ret = btrfs_add_free_space(block_group, start, size);
372 BUG_ON(ret); /* -ENOMEM or logic error */
378 static noinline void caching_thread(struct btrfs_work *work)
380 struct btrfs_block_group_cache *block_group;
381 struct btrfs_fs_info *fs_info;
382 struct btrfs_caching_control *caching_ctl;
383 struct btrfs_root *extent_root;
384 struct btrfs_path *path;
385 struct extent_buffer *leaf;
386 struct btrfs_key key;
392 caching_ctl = container_of(work, struct btrfs_caching_control, work);
393 block_group = caching_ctl->block_group;
394 fs_info = block_group->fs_info;
395 extent_root = fs_info->extent_root;
397 path = btrfs_alloc_path();
401 last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
404 * We don't want to deadlock with somebody trying to allocate a new
405 * extent for the extent root while also trying to search the extent
406 * root to add free space. So we skip locking and search the commit
407 * root, since its read-only
409 path->skip_locking = 1;
410 path->search_commit_root = 1;
415 key.type = BTRFS_EXTENT_ITEM_KEY;
417 mutex_lock(&caching_ctl->mutex);
418 /* need to make sure the commit_root doesn't disappear */
419 down_read(&fs_info->commit_root_sem);
422 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
426 leaf = path->nodes[0];
427 nritems = btrfs_header_nritems(leaf);
430 if (btrfs_fs_closing(fs_info) > 1) {
435 if (path->slots[0] < nritems) {
436 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
438 ret = find_next_key(path, 0, &key);
442 if (need_resched() ||
443 rwsem_is_contended(&fs_info->commit_root_sem)) {
444 caching_ctl->progress = last;
445 btrfs_release_path(path);
446 up_read(&fs_info->commit_root_sem);
447 mutex_unlock(&caching_ctl->mutex);
452 ret = btrfs_next_leaf(extent_root, path);
457 leaf = path->nodes[0];
458 nritems = btrfs_header_nritems(leaf);
462 if (key.objectid < last) {
465 key.type = BTRFS_EXTENT_ITEM_KEY;
467 caching_ctl->progress = last;
468 btrfs_release_path(path);
472 if (key.objectid < block_group->key.objectid) {
477 if (key.objectid >= block_group->key.objectid +
478 block_group->key.offset)
481 if (key.type == BTRFS_EXTENT_ITEM_KEY ||
482 key.type == BTRFS_METADATA_ITEM_KEY) {
483 total_found += add_new_free_space(block_group,
486 if (key.type == BTRFS_METADATA_ITEM_KEY)
487 last = key.objectid +
488 fs_info->tree_root->nodesize;
490 last = key.objectid + key.offset;
492 if (total_found > (1024 * 1024 * 2)) {
494 wake_up(&caching_ctl->wait);
501 total_found += add_new_free_space(block_group, fs_info, last,
502 block_group->key.objectid +
503 block_group->key.offset);
504 caching_ctl->progress = (u64)-1;
506 spin_lock(&block_group->lock);
507 block_group->caching_ctl = NULL;
508 block_group->cached = BTRFS_CACHE_FINISHED;
509 spin_unlock(&block_group->lock);
512 btrfs_free_path(path);
513 up_read(&fs_info->commit_root_sem);
515 free_excluded_extents(extent_root, block_group);
517 mutex_unlock(&caching_ctl->mutex);
520 spin_lock(&block_group->lock);
521 block_group->caching_ctl = NULL;
522 block_group->cached = BTRFS_CACHE_ERROR;
523 spin_unlock(&block_group->lock);
525 wake_up(&caching_ctl->wait);
527 put_caching_control(caching_ctl);
528 btrfs_put_block_group(block_group);
531 static int cache_block_group(struct btrfs_block_group_cache *cache,
535 struct btrfs_fs_info *fs_info = cache->fs_info;
536 struct btrfs_caching_control *caching_ctl;
539 caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_NOFS);
543 INIT_LIST_HEAD(&caching_ctl->list);
544 mutex_init(&caching_ctl->mutex);
545 init_waitqueue_head(&caching_ctl->wait);
546 caching_ctl->block_group = cache;
547 caching_ctl->progress = cache->key.objectid;
548 atomic_set(&caching_ctl->count, 1);
549 btrfs_init_work(&caching_ctl->work, btrfs_cache_helper,
550 caching_thread, NULL, NULL);
552 spin_lock(&cache->lock);
554 * This should be a rare occasion, but this could happen I think in the
555 * case where one thread starts to load the space cache info, and then
556 * some other thread starts a transaction commit which tries to do an
557 * allocation while the other thread is still loading the space cache
558 * info. The previous loop should have kept us from choosing this block
559 * group, but if we've moved to the state where we will wait on caching
560 * block groups we need to first check if we're doing a fast load here,
561 * so we can wait for it to finish, otherwise we could end up allocating
562 * from a block group who's cache gets evicted for one reason or
565 while (cache->cached == BTRFS_CACHE_FAST) {
566 struct btrfs_caching_control *ctl;
568 ctl = cache->caching_ctl;
569 atomic_inc(&ctl->count);
570 prepare_to_wait(&ctl->wait, &wait, TASK_UNINTERRUPTIBLE);
571 spin_unlock(&cache->lock);
575 finish_wait(&ctl->wait, &wait);
576 put_caching_control(ctl);
577 spin_lock(&cache->lock);
580 if (cache->cached != BTRFS_CACHE_NO) {
581 spin_unlock(&cache->lock);
585 WARN_ON(cache->caching_ctl);
586 cache->caching_ctl = caching_ctl;
587 cache->cached = BTRFS_CACHE_FAST;
588 spin_unlock(&cache->lock);
590 if (fs_info->mount_opt & BTRFS_MOUNT_SPACE_CACHE) {
591 mutex_lock(&caching_ctl->mutex);
592 ret = load_free_space_cache(fs_info, cache);
594 spin_lock(&cache->lock);
596 cache->caching_ctl = NULL;
597 cache->cached = BTRFS_CACHE_FINISHED;
598 cache->last_byte_to_unpin = (u64)-1;
599 caching_ctl->progress = (u64)-1;
601 if (load_cache_only) {
602 cache->caching_ctl = NULL;
603 cache->cached = BTRFS_CACHE_NO;
605 cache->cached = BTRFS_CACHE_STARTED;
606 cache->has_caching_ctl = 1;
609 spin_unlock(&cache->lock);
610 mutex_unlock(&caching_ctl->mutex);
612 wake_up(&caching_ctl->wait);
614 put_caching_control(caching_ctl);
615 free_excluded_extents(fs_info->extent_root, cache);
620 * We are not going to do the fast caching, set cached to the
621 * appropriate value and wakeup any waiters.
623 spin_lock(&cache->lock);
624 if (load_cache_only) {
625 cache->caching_ctl = NULL;
626 cache->cached = BTRFS_CACHE_NO;
628 cache->cached = BTRFS_CACHE_STARTED;
629 cache->has_caching_ctl = 1;
631 spin_unlock(&cache->lock);
632 wake_up(&caching_ctl->wait);
635 if (load_cache_only) {
636 put_caching_control(caching_ctl);
640 down_write(&fs_info->commit_root_sem);
641 atomic_inc(&caching_ctl->count);
642 list_add_tail(&caching_ctl->list, &fs_info->caching_block_groups);
643 up_write(&fs_info->commit_root_sem);
645 btrfs_get_block_group(cache);
647 btrfs_queue_work(fs_info->caching_workers, &caching_ctl->work);
653 * return the block group that starts at or after bytenr
655 static struct btrfs_block_group_cache *
656 btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr)
658 struct btrfs_block_group_cache *cache;
660 cache = block_group_cache_tree_search(info, bytenr, 0);
666 * return the block group that contains the given bytenr
668 struct btrfs_block_group_cache *btrfs_lookup_block_group(
669 struct btrfs_fs_info *info,
672 struct btrfs_block_group_cache *cache;
674 cache = block_group_cache_tree_search(info, bytenr, 1);
679 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
682 struct list_head *head = &info->space_info;
683 struct btrfs_space_info *found;
685 flags &= BTRFS_BLOCK_GROUP_TYPE_MASK;
688 list_for_each_entry_rcu(found, head, list) {
689 if (found->flags & flags) {
699 * after adding space to the filesystem, we need to clear the full flags
700 * on all the space infos.
702 void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
704 struct list_head *head = &info->space_info;
705 struct btrfs_space_info *found;
708 list_for_each_entry_rcu(found, head, list)
713 /* simple helper to search for an existing data extent at a given offset */
714 int btrfs_lookup_data_extent(struct btrfs_root *root, u64 start, u64 len)
717 struct btrfs_key key;
718 struct btrfs_path *path;
720 path = btrfs_alloc_path();
724 key.objectid = start;
726 key.type = BTRFS_EXTENT_ITEM_KEY;
727 ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path,
729 btrfs_free_path(path);
734 * helper function to lookup reference count and flags of a tree block.
736 * the head node for delayed ref is used to store the sum of all the
737 * reference count modifications queued up in the rbtree. the head
738 * node may also store the extent flags to set. This way you can check
739 * to see what the reference count and extent flags would be if all of
740 * the delayed refs are not processed.
742 int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
743 struct btrfs_root *root, u64 bytenr,
744 u64 offset, int metadata, u64 *refs, u64 *flags)
746 struct btrfs_delayed_ref_head *head;
747 struct btrfs_delayed_ref_root *delayed_refs;
748 struct btrfs_path *path;
749 struct btrfs_extent_item *ei;
750 struct extent_buffer *leaf;
751 struct btrfs_key key;
758 * If we don't have skinny metadata, don't bother doing anything
761 if (metadata && !btrfs_fs_incompat(root->fs_info, SKINNY_METADATA)) {
762 offset = root->nodesize;
766 path = btrfs_alloc_path();
771 path->skip_locking = 1;
772 path->search_commit_root = 1;
776 key.objectid = bytenr;
779 key.type = BTRFS_METADATA_ITEM_KEY;
781 key.type = BTRFS_EXTENT_ITEM_KEY;
783 ret = btrfs_search_slot(trans, root->fs_info->extent_root,
788 if (ret > 0 && metadata && key.type == BTRFS_METADATA_ITEM_KEY) {
789 if (path->slots[0]) {
791 btrfs_item_key_to_cpu(path->nodes[0], &key,
793 if (key.objectid == bytenr &&
794 key.type == BTRFS_EXTENT_ITEM_KEY &&
795 key.offset == root->nodesize)
801 leaf = path->nodes[0];
802 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
803 if (item_size >= sizeof(*ei)) {
804 ei = btrfs_item_ptr(leaf, path->slots[0],
805 struct btrfs_extent_item);
806 num_refs = btrfs_extent_refs(leaf, ei);
807 extent_flags = btrfs_extent_flags(leaf, ei);
809 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
810 struct btrfs_extent_item_v0 *ei0;
811 BUG_ON(item_size != sizeof(*ei0));
812 ei0 = btrfs_item_ptr(leaf, path->slots[0],
813 struct btrfs_extent_item_v0);
814 num_refs = btrfs_extent_refs_v0(leaf, ei0);
815 /* FIXME: this isn't correct for data */
816 extent_flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
821 BUG_ON(num_refs == 0);
831 delayed_refs = &trans->transaction->delayed_refs;
832 spin_lock(&delayed_refs->lock);
833 head = btrfs_find_delayed_ref_head(trans, bytenr);
835 if (!mutex_trylock(&head->mutex)) {
836 atomic_inc(&head->node.refs);
837 spin_unlock(&delayed_refs->lock);
839 btrfs_release_path(path);
842 * Mutex was contended, block until it's released and try
845 mutex_lock(&head->mutex);
846 mutex_unlock(&head->mutex);
847 btrfs_put_delayed_ref(&head->node);
850 spin_lock(&head->lock);
851 if (head->extent_op && head->extent_op->update_flags)
852 extent_flags |= head->extent_op->flags_to_set;
854 BUG_ON(num_refs == 0);
856 num_refs += head->node.ref_mod;
857 spin_unlock(&head->lock);
858 mutex_unlock(&head->mutex);
860 spin_unlock(&delayed_refs->lock);
862 WARN_ON(num_refs == 0);
866 *flags = extent_flags;
868 btrfs_free_path(path);
873 * Back reference rules. Back refs have three main goals:
875 * 1) differentiate between all holders of references to an extent so that
876 * when a reference is dropped we can make sure it was a valid reference
877 * before freeing the extent.
879 * 2) Provide enough information to quickly find the holders of an extent
880 * if we notice a given block is corrupted or bad.
882 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
883 * maintenance. This is actually the same as #2, but with a slightly
884 * different use case.
886 * There are two kinds of back refs. The implicit back refs is optimized
887 * for pointers in non-shared tree blocks. For a given pointer in a block,
888 * back refs of this kind provide information about the block's owner tree
889 * and the pointer's key. These information allow us to find the block by
890 * b-tree searching. The full back refs is for pointers in tree blocks not
891 * referenced by their owner trees. The location of tree block is recorded
892 * in the back refs. Actually the full back refs is generic, and can be
893 * used in all cases the implicit back refs is used. The major shortcoming
894 * of the full back refs is its overhead. Every time a tree block gets
895 * COWed, we have to update back refs entry for all pointers in it.
897 * For a newly allocated tree block, we use implicit back refs for
898 * pointers in it. This means most tree related operations only involve
899 * implicit back refs. For a tree block created in old transaction, the
900 * only way to drop a reference to it is COW it. So we can detect the
901 * event that tree block loses its owner tree's reference and do the
902 * back refs conversion.
904 * When a tree block is COW'd through a tree, there are four cases:
906 * The reference count of the block is one and the tree is the block's
907 * owner tree. Nothing to do in this case.
909 * The reference count of the block is one and the tree is not the
910 * block's owner tree. In this case, full back refs is used for pointers
911 * in the block. Remove these full back refs, add implicit back refs for
912 * every pointers in the new block.
914 * The reference count of the block is greater than one and the tree is
915 * the block's owner tree. In this case, implicit back refs is used for
916 * pointers in the block. Add full back refs for every pointers in the
917 * block, increase lower level extents' reference counts. The original
918 * implicit back refs are entailed to the new block.
920 * The reference count of the block is greater than one and the tree is
921 * not the block's owner tree. Add implicit back refs for every pointer in
922 * the new block, increase lower level extents' reference count.
924 * Back Reference Key composing:
926 * The key objectid corresponds to the first byte in the extent,
927 * The key type is used to differentiate between types of back refs.
928 * There are different meanings of the key offset for different types
931 * File extents can be referenced by:
933 * - multiple snapshots, subvolumes, or different generations in one subvol
934 * - different files inside a single subvolume
935 * - different offsets inside a file (bookend extents in file.c)
937 * The extent ref structure for the implicit back refs has fields for:
939 * - Objectid of the subvolume root
940 * - objectid of the file holding the reference
941 * - original offset in the file
942 * - how many bookend extents
944 * The key offset for the implicit back refs is hash of the first
947 * The extent ref structure for the full back refs has field for:
949 * - number of pointers in the tree leaf
951 * The key offset for the implicit back refs is the first byte of
954 * When a file extent is allocated, The implicit back refs is used.
955 * the fields are filled in:
957 * (root_key.objectid, inode objectid, offset in file, 1)
959 * When a file extent is removed file truncation, we find the
960 * corresponding implicit back refs and check the following fields:
962 * (btrfs_header_owner(leaf), inode objectid, offset in file)
964 * Btree extents can be referenced by:
966 * - Different subvolumes
968 * Both the implicit back refs and the full back refs for tree blocks
969 * only consist of key. The key offset for the implicit back refs is
970 * objectid of block's owner tree. The key offset for the full back refs
971 * is the first byte of parent block.
973 * When implicit back refs is used, information about the lowest key and
974 * level of the tree block are required. These information are stored in
975 * tree block info structure.
978 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
979 static int convert_extent_item_v0(struct btrfs_trans_handle *trans,
980 struct btrfs_root *root,
981 struct btrfs_path *path,
982 u64 owner, u32 extra_size)
984 struct btrfs_extent_item *item;
985 struct btrfs_extent_item_v0 *ei0;
986 struct btrfs_extent_ref_v0 *ref0;
987 struct btrfs_tree_block_info *bi;
988 struct extent_buffer *leaf;
989 struct btrfs_key key;
990 struct btrfs_key found_key;
991 u32 new_size = sizeof(*item);
995 leaf = path->nodes[0];
996 BUG_ON(btrfs_item_size_nr(leaf, path->slots[0]) != sizeof(*ei0));
998 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
999 ei0 = btrfs_item_ptr(leaf, path->slots[0],
1000 struct btrfs_extent_item_v0);
1001 refs = btrfs_extent_refs_v0(leaf, ei0);
1003 if (owner == (u64)-1) {
1005 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1006 ret = btrfs_next_leaf(root, path);
1009 BUG_ON(ret > 0); /* Corruption */
1010 leaf = path->nodes[0];
1012 btrfs_item_key_to_cpu(leaf, &found_key,
1014 BUG_ON(key.objectid != found_key.objectid);
1015 if (found_key.type != BTRFS_EXTENT_REF_V0_KEY) {
1019 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1020 struct btrfs_extent_ref_v0);
1021 owner = btrfs_ref_objectid_v0(leaf, ref0);
1025 btrfs_release_path(path);
1027 if (owner < BTRFS_FIRST_FREE_OBJECTID)
1028 new_size += sizeof(*bi);
1030 new_size -= sizeof(*ei0);
1031 ret = btrfs_search_slot(trans, root, &key, path,
1032 new_size + extra_size, 1);
1035 BUG_ON(ret); /* Corruption */
1037 btrfs_extend_item(root, path, new_size);
1039 leaf = path->nodes[0];
1040 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1041 btrfs_set_extent_refs(leaf, item, refs);
1042 /* FIXME: get real generation */
1043 btrfs_set_extent_generation(leaf, item, 0);
1044 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1045 btrfs_set_extent_flags(leaf, item,
1046 BTRFS_EXTENT_FLAG_TREE_BLOCK |
1047 BTRFS_BLOCK_FLAG_FULL_BACKREF);
1048 bi = (struct btrfs_tree_block_info *)(item + 1);
1049 /* FIXME: get first key of the block */
1050 memset_extent_buffer(leaf, 0, (unsigned long)bi, sizeof(*bi));
1051 btrfs_set_tree_block_level(leaf, bi, (int)owner);
1053 btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_DATA);
1055 btrfs_mark_buffer_dirty(leaf);
1060 static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
1062 u32 high_crc = ~(u32)0;
1063 u32 low_crc = ~(u32)0;
1066 lenum = cpu_to_le64(root_objectid);
1067 high_crc = btrfs_crc32c(high_crc, &lenum, sizeof(lenum));
1068 lenum = cpu_to_le64(owner);
1069 low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
1070 lenum = cpu_to_le64(offset);
1071 low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
1073 return ((u64)high_crc << 31) ^ (u64)low_crc;
1076 static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
1077 struct btrfs_extent_data_ref *ref)
1079 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
1080 btrfs_extent_data_ref_objectid(leaf, ref),
1081 btrfs_extent_data_ref_offset(leaf, ref));
1084 static int match_extent_data_ref(struct extent_buffer *leaf,
1085 struct btrfs_extent_data_ref *ref,
1086 u64 root_objectid, u64 owner, u64 offset)
1088 if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
1089 btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
1090 btrfs_extent_data_ref_offset(leaf, ref) != offset)
1095 static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
1096 struct btrfs_root *root,
1097 struct btrfs_path *path,
1098 u64 bytenr, u64 parent,
1100 u64 owner, u64 offset)
1102 struct btrfs_key key;
1103 struct btrfs_extent_data_ref *ref;
1104 struct extent_buffer *leaf;
1110 key.objectid = bytenr;
1112 key.type = BTRFS_SHARED_DATA_REF_KEY;
1113 key.offset = parent;
1115 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1116 key.offset = hash_extent_data_ref(root_objectid,
1121 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1130 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1131 key.type = BTRFS_EXTENT_REF_V0_KEY;
1132 btrfs_release_path(path);
1133 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1144 leaf = path->nodes[0];
1145 nritems = btrfs_header_nritems(leaf);
1147 if (path->slots[0] >= nritems) {
1148 ret = btrfs_next_leaf(root, path);
1154 leaf = path->nodes[0];
1155 nritems = btrfs_header_nritems(leaf);
1159 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1160 if (key.objectid != bytenr ||
1161 key.type != BTRFS_EXTENT_DATA_REF_KEY)
1164 ref = btrfs_item_ptr(leaf, path->slots[0],
1165 struct btrfs_extent_data_ref);
1167 if (match_extent_data_ref(leaf, ref, root_objectid,
1170 btrfs_release_path(path);
1182 static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
1183 struct btrfs_root *root,
1184 struct btrfs_path *path,
1185 u64 bytenr, u64 parent,
1186 u64 root_objectid, u64 owner,
1187 u64 offset, int refs_to_add)
1189 struct btrfs_key key;
1190 struct extent_buffer *leaf;
1195 key.objectid = bytenr;
1197 key.type = BTRFS_SHARED_DATA_REF_KEY;
1198 key.offset = parent;
1199 size = sizeof(struct btrfs_shared_data_ref);
1201 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1202 key.offset = hash_extent_data_ref(root_objectid,
1204 size = sizeof(struct btrfs_extent_data_ref);
1207 ret = btrfs_insert_empty_item(trans, root, path, &key, size);
1208 if (ret && ret != -EEXIST)
1211 leaf = path->nodes[0];
1213 struct btrfs_shared_data_ref *ref;
1214 ref = btrfs_item_ptr(leaf, path->slots[0],
1215 struct btrfs_shared_data_ref);
1217 btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
1219 num_refs = btrfs_shared_data_ref_count(leaf, ref);
1220 num_refs += refs_to_add;
1221 btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
1224 struct btrfs_extent_data_ref *ref;
1225 while (ret == -EEXIST) {
1226 ref = btrfs_item_ptr(leaf, path->slots[0],
1227 struct btrfs_extent_data_ref);
1228 if (match_extent_data_ref(leaf, ref, root_objectid,
1231 btrfs_release_path(path);
1233 ret = btrfs_insert_empty_item(trans, root, path, &key,
1235 if (ret && ret != -EEXIST)
1238 leaf = path->nodes[0];
1240 ref = btrfs_item_ptr(leaf, path->slots[0],
1241 struct btrfs_extent_data_ref);
1243 btrfs_set_extent_data_ref_root(leaf, ref,
1245 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
1246 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
1247 btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
1249 num_refs = btrfs_extent_data_ref_count(leaf, ref);
1250 num_refs += refs_to_add;
1251 btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
1254 btrfs_mark_buffer_dirty(leaf);
1257 btrfs_release_path(path);
1261 static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
1262 struct btrfs_root *root,
1263 struct btrfs_path *path,
1264 int refs_to_drop, int *last_ref)
1266 struct btrfs_key key;
1267 struct btrfs_extent_data_ref *ref1 = NULL;
1268 struct btrfs_shared_data_ref *ref2 = NULL;
1269 struct extent_buffer *leaf;
1273 leaf = path->nodes[0];
1274 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1276 if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1277 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1278 struct btrfs_extent_data_ref);
1279 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1280 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1281 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1282 struct btrfs_shared_data_ref);
1283 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1284 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1285 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1286 struct btrfs_extent_ref_v0 *ref0;
1287 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1288 struct btrfs_extent_ref_v0);
1289 num_refs = btrfs_ref_count_v0(leaf, ref0);
1295 BUG_ON(num_refs < refs_to_drop);
1296 num_refs -= refs_to_drop;
1298 if (num_refs == 0) {
1299 ret = btrfs_del_item(trans, root, path);
1302 if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
1303 btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
1304 else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
1305 btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
1306 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1308 struct btrfs_extent_ref_v0 *ref0;
1309 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1310 struct btrfs_extent_ref_v0);
1311 btrfs_set_ref_count_v0(leaf, ref0, num_refs);
1314 btrfs_mark_buffer_dirty(leaf);
1319 static noinline u32 extent_data_ref_count(struct btrfs_path *path,
1320 struct btrfs_extent_inline_ref *iref)
1322 struct btrfs_key key;
1323 struct extent_buffer *leaf;
1324 struct btrfs_extent_data_ref *ref1;
1325 struct btrfs_shared_data_ref *ref2;
1328 leaf = path->nodes[0];
1329 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1331 if (btrfs_extent_inline_ref_type(leaf, iref) ==
1332 BTRFS_EXTENT_DATA_REF_KEY) {
1333 ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
1334 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1336 ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
1337 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1339 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1340 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1341 struct btrfs_extent_data_ref);
1342 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1343 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1344 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1345 struct btrfs_shared_data_ref);
1346 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1347 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1348 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1349 struct btrfs_extent_ref_v0 *ref0;
1350 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1351 struct btrfs_extent_ref_v0);
1352 num_refs = btrfs_ref_count_v0(leaf, ref0);
1360 static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
1361 struct btrfs_root *root,
1362 struct btrfs_path *path,
1363 u64 bytenr, u64 parent,
1366 struct btrfs_key key;
1369 key.objectid = bytenr;
1371 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1372 key.offset = parent;
1374 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1375 key.offset = root_objectid;
1378 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1381 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1382 if (ret == -ENOENT && parent) {
1383 btrfs_release_path(path);
1384 key.type = BTRFS_EXTENT_REF_V0_KEY;
1385 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1393 static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
1394 struct btrfs_root *root,
1395 struct btrfs_path *path,
1396 u64 bytenr, u64 parent,
1399 struct btrfs_key key;
1402 key.objectid = bytenr;
1404 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1405 key.offset = parent;
1407 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1408 key.offset = root_objectid;
1411 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1412 btrfs_release_path(path);
1416 static inline int extent_ref_type(u64 parent, u64 owner)
1419 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1421 type = BTRFS_SHARED_BLOCK_REF_KEY;
1423 type = BTRFS_TREE_BLOCK_REF_KEY;
1426 type = BTRFS_SHARED_DATA_REF_KEY;
1428 type = BTRFS_EXTENT_DATA_REF_KEY;
1433 static int find_next_key(struct btrfs_path *path, int level,
1434 struct btrfs_key *key)
1437 for (; level < BTRFS_MAX_LEVEL; level++) {
1438 if (!path->nodes[level])
1440 if (path->slots[level] + 1 >=
1441 btrfs_header_nritems(path->nodes[level]))
1444 btrfs_item_key_to_cpu(path->nodes[level], key,
1445 path->slots[level] + 1);
1447 btrfs_node_key_to_cpu(path->nodes[level], key,
1448 path->slots[level] + 1);
1455 * look for inline back ref. if back ref is found, *ref_ret is set
1456 * to the address of inline back ref, and 0 is returned.
1458 * if back ref isn't found, *ref_ret is set to the address where it
1459 * should be inserted, and -ENOENT is returned.
1461 * if insert is true and there are too many inline back refs, the path
1462 * points to the extent item, and -EAGAIN is returned.
1464 * NOTE: inline back refs are ordered in the same way that back ref
1465 * items in the tree are ordered.
1467 static noinline_for_stack
1468 int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
1469 struct btrfs_root *root,
1470 struct btrfs_path *path,
1471 struct btrfs_extent_inline_ref **ref_ret,
1472 u64 bytenr, u64 num_bytes,
1473 u64 parent, u64 root_objectid,
1474 u64 owner, u64 offset, int insert)
1476 struct btrfs_key key;
1477 struct extent_buffer *leaf;
1478 struct btrfs_extent_item *ei;
1479 struct btrfs_extent_inline_ref *iref;
1489 bool skinny_metadata = btrfs_fs_incompat(root->fs_info,
1492 key.objectid = bytenr;
1493 key.type = BTRFS_EXTENT_ITEM_KEY;
1494 key.offset = num_bytes;
1496 want = extent_ref_type(parent, owner);
1498 extra_size = btrfs_extent_inline_ref_size(want);
1499 path->keep_locks = 1;
1504 * Owner is our parent level, so we can just add one to get the level
1505 * for the block we are interested in.
1507 if (skinny_metadata && owner < BTRFS_FIRST_FREE_OBJECTID) {
1508 key.type = BTRFS_METADATA_ITEM_KEY;
1513 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
1520 * We may be a newly converted file system which still has the old fat
1521 * extent entries for metadata, so try and see if we have one of those.
1523 if (ret > 0 && skinny_metadata) {
1524 skinny_metadata = false;
1525 if (path->slots[0]) {
1527 btrfs_item_key_to_cpu(path->nodes[0], &key,
1529 if (key.objectid == bytenr &&
1530 key.type == BTRFS_EXTENT_ITEM_KEY &&
1531 key.offset == num_bytes)
1535 key.objectid = bytenr;
1536 key.type = BTRFS_EXTENT_ITEM_KEY;
1537 key.offset = num_bytes;
1538 btrfs_release_path(path);
1543 if (ret && !insert) {
1546 } else if (WARN_ON(ret)) {
1551 leaf = path->nodes[0];
1552 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1553 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1554 if (item_size < sizeof(*ei)) {
1559 ret = convert_extent_item_v0(trans, root, path, owner,
1565 leaf = path->nodes[0];
1566 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1569 BUG_ON(item_size < sizeof(*ei));
1571 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1572 flags = btrfs_extent_flags(leaf, ei);
1574 ptr = (unsigned long)(ei + 1);
1575 end = (unsigned long)ei + item_size;
1577 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK && !skinny_metadata) {
1578 ptr += sizeof(struct btrfs_tree_block_info);
1588 iref = (struct btrfs_extent_inline_ref *)ptr;
1589 type = btrfs_extent_inline_ref_type(leaf, iref);
1593 ptr += btrfs_extent_inline_ref_size(type);
1597 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1598 struct btrfs_extent_data_ref *dref;
1599 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1600 if (match_extent_data_ref(leaf, dref, root_objectid,
1605 if (hash_extent_data_ref_item(leaf, dref) <
1606 hash_extent_data_ref(root_objectid, owner, offset))
1610 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1612 if (parent == ref_offset) {
1616 if (ref_offset < parent)
1619 if (root_objectid == ref_offset) {
1623 if (ref_offset < root_objectid)
1627 ptr += btrfs_extent_inline_ref_size(type);
1629 if (err == -ENOENT && insert) {
1630 if (item_size + extra_size >=
1631 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
1636 * To add new inline back ref, we have to make sure
1637 * there is no corresponding back ref item.
1638 * For simplicity, we just do not add new inline back
1639 * ref if there is any kind of item for this block
1641 if (find_next_key(path, 0, &key) == 0 &&
1642 key.objectid == bytenr &&
1643 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
1648 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
1651 path->keep_locks = 0;
1652 btrfs_unlock_up_safe(path, 1);
1658 * helper to add new inline back ref
1660 static noinline_for_stack
1661 void setup_inline_extent_backref(struct btrfs_root *root,
1662 struct btrfs_path *path,
1663 struct btrfs_extent_inline_ref *iref,
1664 u64 parent, u64 root_objectid,
1665 u64 owner, u64 offset, int refs_to_add,
1666 struct btrfs_delayed_extent_op *extent_op)
1668 struct extent_buffer *leaf;
1669 struct btrfs_extent_item *ei;
1672 unsigned long item_offset;
1677 leaf = path->nodes[0];
1678 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1679 item_offset = (unsigned long)iref - (unsigned long)ei;
1681 type = extent_ref_type(parent, owner);
1682 size = btrfs_extent_inline_ref_size(type);
1684 btrfs_extend_item(root, path, size);
1686 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1687 refs = btrfs_extent_refs(leaf, ei);
1688 refs += refs_to_add;
1689 btrfs_set_extent_refs(leaf, ei, refs);
1691 __run_delayed_extent_op(extent_op, leaf, ei);
1693 ptr = (unsigned long)ei + item_offset;
1694 end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
1695 if (ptr < end - size)
1696 memmove_extent_buffer(leaf, ptr + size, ptr,
1699 iref = (struct btrfs_extent_inline_ref *)ptr;
1700 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1701 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1702 struct btrfs_extent_data_ref *dref;
1703 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1704 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1705 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1706 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1707 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1708 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1709 struct btrfs_shared_data_ref *sref;
1710 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1711 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1712 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1713 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1714 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1716 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1718 btrfs_mark_buffer_dirty(leaf);
1721 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1722 struct btrfs_root *root,
1723 struct btrfs_path *path,
1724 struct btrfs_extent_inline_ref **ref_ret,
1725 u64 bytenr, u64 num_bytes, u64 parent,
1726 u64 root_objectid, u64 owner, u64 offset)
1730 ret = lookup_inline_extent_backref(trans, root, path, ref_ret,
1731 bytenr, num_bytes, parent,
1732 root_objectid, owner, offset, 0);
1736 btrfs_release_path(path);
1739 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1740 ret = lookup_tree_block_ref(trans, root, path, bytenr, parent,
1743 ret = lookup_extent_data_ref(trans, root, path, bytenr, parent,
1744 root_objectid, owner, offset);
1750 * helper to update/remove inline back ref
1752 static noinline_for_stack
1753 void update_inline_extent_backref(struct btrfs_root *root,
1754 struct btrfs_path *path,
1755 struct btrfs_extent_inline_ref *iref,
1757 struct btrfs_delayed_extent_op *extent_op,
1760 struct extent_buffer *leaf;
1761 struct btrfs_extent_item *ei;
1762 struct btrfs_extent_data_ref *dref = NULL;
1763 struct btrfs_shared_data_ref *sref = NULL;
1771 leaf = path->nodes[0];
1772 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1773 refs = btrfs_extent_refs(leaf, ei);
1774 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1775 refs += refs_to_mod;
1776 btrfs_set_extent_refs(leaf, ei, refs);
1778 __run_delayed_extent_op(extent_op, leaf, ei);
1780 type = btrfs_extent_inline_ref_type(leaf, iref);
1782 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1783 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1784 refs = btrfs_extent_data_ref_count(leaf, dref);
1785 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1786 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1787 refs = btrfs_shared_data_ref_count(leaf, sref);
1790 BUG_ON(refs_to_mod != -1);
1793 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1794 refs += refs_to_mod;
1797 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1798 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1800 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1803 size = btrfs_extent_inline_ref_size(type);
1804 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1805 ptr = (unsigned long)iref;
1806 end = (unsigned long)ei + item_size;
1807 if (ptr + size < end)
1808 memmove_extent_buffer(leaf, ptr, ptr + size,
1811 btrfs_truncate_item(root, path, item_size, 1);
1813 btrfs_mark_buffer_dirty(leaf);
1816 static noinline_for_stack
1817 int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1818 struct btrfs_root *root,
1819 struct btrfs_path *path,
1820 u64 bytenr, u64 num_bytes, u64 parent,
1821 u64 root_objectid, u64 owner,
1822 u64 offset, int refs_to_add,
1823 struct btrfs_delayed_extent_op *extent_op)
1825 struct btrfs_extent_inline_ref *iref;
1828 ret = lookup_inline_extent_backref(trans, root, path, &iref,
1829 bytenr, num_bytes, parent,
1830 root_objectid, owner, offset, 1);
1832 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
1833 update_inline_extent_backref(root, path, iref,
1834 refs_to_add, extent_op, NULL);
1835 } else if (ret == -ENOENT) {
1836 setup_inline_extent_backref(root, path, iref, parent,
1837 root_objectid, owner, offset,
1838 refs_to_add, extent_op);
1844 static int insert_extent_backref(struct btrfs_trans_handle *trans,
1845 struct btrfs_root *root,
1846 struct btrfs_path *path,
1847 u64 bytenr, u64 parent, u64 root_objectid,
1848 u64 owner, u64 offset, int refs_to_add)
1851 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1852 BUG_ON(refs_to_add != 1);
1853 ret = insert_tree_block_ref(trans, root, path, bytenr,
1854 parent, root_objectid);
1856 ret = insert_extent_data_ref(trans, root, path, bytenr,
1857 parent, root_objectid,
1858 owner, offset, refs_to_add);
1863 static int remove_extent_backref(struct btrfs_trans_handle *trans,
1864 struct btrfs_root *root,
1865 struct btrfs_path *path,
1866 struct btrfs_extent_inline_ref *iref,
1867 int refs_to_drop, int is_data, int *last_ref)
1871 BUG_ON(!is_data && refs_to_drop != 1);
1873 update_inline_extent_backref(root, path, iref,
1874 -refs_to_drop, NULL, last_ref);
1875 } else if (is_data) {
1876 ret = remove_extent_data_ref(trans, root, path, refs_to_drop,
1880 ret = btrfs_del_item(trans, root, path);
1885 #define in_range(b, first, len) ((b) >= (first) && (b) < (first) + (len))
1886 static int btrfs_issue_discard(struct block_device *bdev, u64 start, u64 len,
1887 u64 *discarded_bytes)
1890 u64 bytes_left, end;
1891 u64 aligned_start = ALIGN(start, 1 << 9);
1893 if (WARN_ON(start != aligned_start)) {
1894 len -= aligned_start - start;
1895 len = round_down(len, 1 << 9);
1896 start = aligned_start;
1899 *discarded_bytes = 0;
1907 /* Skip any superblocks on this device. */
1908 for (j = 0; j < BTRFS_SUPER_MIRROR_MAX; j++) {
1909 u64 sb_start = btrfs_sb_offset(j);
1910 u64 sb_end = sb_start + BTRFS_SUPER_INFO_SIZE;
1911 u64 size = sb_start - start;
1913 if (!in_range(sb_start, start, bytes_left) &&
1914 !in_range(sb_end, start, bytes_left) &&
1915 !in_range(start, sb_start, BTRFS_SUPER_INFO_SIZE))
1919 * Superblock spans beginning of range. Adjust start and
1922 if (sb_start <= start) {
1923 start += sb_end - start;
1928 bytes_left = end - start;
1933 ret = blkdev_issue_discard(bdev, start >> 9, size >> 9,
1936 *discarded_bytes += size;
1937 else if (ret != -EOPNOTSUPP)
1946 bytes_left = end - start;
1950 ret = blkdev_issue_discard(bdev, start >> 9, bytes_left >> 9,
1953 *discarded_bytes += bytes_left;
1958 int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
1959 u64 num_bytes, u64 *actual_bytes)
1962 u64 discarded_bytes = 0;
1963 struct btrfs_bio *bbio = NULL;
1966 /* Tell the block device(s) that the sectors can be discarded */
1967 ret = btrfs_map_block(root->fs_info, REQ_DISCARD,
1968 bytenr, &num_bytes, &bbio, 0);
1969 /* Error condition is -ENOMEM */
1971 struct btrfs_bio_stripe *stripe = bbio->stripes;
1975 for (i = 0; i < bbio->num_stripes; i++, stripe++) {
1977 if (!stripe->dev->can_discard)
1980 ret = btrfs_issue_discard(stripe->dev->bdev,
1985 discarded_bytes += bytes;
1986 else if (ret != -EOPNOTSUPP)
1987 break; /* Logic errors or -ENOMEM, or -EIO but I don't know how that could happen JDM */
1990 * Just in case we get back EOPNOTSUPP for some reason,
1991 * just ignore the return value so we don't screw up
1992 * people calling discard_extent.
1996 btrfs_put_bbio(bbio);
2000 *actual_bytes = discarded_bytes;
2003 if (ret == -EOPNOTSUPP)
2008 /* Can return -ENOMEM */
2009 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
2010 struct btrfs_root *root,
2011 u64 bytenr, u64 num_bytes, u64 parent,
2012 u64 root_objectid, u64 owner, u64 offset,
2016 struct btrfs_fs_info *fs_info = root->fs_info;
2018 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID &&
2019 root_objectid == BTRFS_TREE_LOG_OBJECTID);
2021 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
2022 ret = btrfs_add_delayed_tree_ref(fs_info, trans, bytenr,
2024 parent, root_objectid, (int)owner,
2025 BTRFS_ADD_DELAYED_REF, NULL, no_quota);
2027 ret = btrfs_add_delayed_data_ref(fs_info, trans, bytenr,
2029 parent, root_objectid, owner, offset,
2030 BTRFS_ADD_DELAYED_REF, NULL, no_quota);
2035 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
2036 struct btrfs_root *root,
2037 struct btrfs_delayed_ref_node *node,
2038 u64 parent, u64 root_objectid,
2039 u64 owner, u64 offset, int refs_to_add,
2040 struct btrfs_delayed_extent_op *extent_op)
2042 struct btrfs_fs_info *fs_info = root->fs_info;
2043 struct btrfs_path *path;
2044 struct extent_buffer *leaf;
2045 struct btrfs_extent_item *item;
2046 struct btrfs_key key;
2047 u64 bytenr = node->bytenr;
2048 u64 num_bytes = node->num_bytes;
2051 int no_quota = node->no_quota;
2053 path = btrfs_alloc_path();
2057 if (!is_fstree(root_objectid) || !root->fs_info->quota_enabled)
2061 path->leave_spinning = 1;
2062 /* this will setup the path even if it fails to insert the back ref */
2063 ret = insert_inline_extent_backref(trans, fs_info->extent_root, path,
2064 bytenr, num_bytes, parent,
2065 root_objectid, owner, offset,
2066 refs_to_add, extent_op);
2067 if ((ret < 0 && ret != -EAGAIN) || !ret)
2071 * Ok we had -EAGAIN which means we didn't have space to insert and
2072 * inline extent ref, so just update the reference count and add a
2075 leaf = path->nodes[0];
2076 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2077 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2078 refs = btrfs_extent_refs(leaf, item);
2079 btrfs_set_extent_refs(leaf, item, refs + refs_to_add);
2081 __run_delayed_extent_op(extent_op, leaf, item);
2083 btrfs_mark_buffer_dirty(leaf);
2084 btrfs_release_path(path);
2087 path->leave_spinning = 1;
2088 /* now insert the actual backref */
2089 ret = insert_extent_backref(trans, root->fs_info->extent_root,
2090 path, bytenr, parent, root_objectid,
2091 owner, offset, refs_to_add);
2093 btrfs_abort_transaction(trans, root, ret);
2095 btrfs_free_path(path);
2099 static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
2100 struct btrfs_root *root,
2101 struct btrfs_delayed_ref_node *node,
2102 struct btrfs_delayed_extent_op *extent_op,
2103 int insert_reserved)
2106 struct btrfs_delayed_data_ref *ref;
2107 struct btrfs_key ins;
2112 ins.objectid = node->bytenr;
2113 ins.offset = node->num_bytes;
2114 ins.type = BTRFS_EXTENT_ITEM_KEY;
2116 ref = btrfs_delayed_node_to_data_ref(node);
2117 trace_run_delayed_data_ref(node, ref, node->action);
2119 if (node->type == BTRFS_SHARED_DATA_REF_KEY)
2120 parent = ref->parent;
2121 ref_root = ref->root;
2123 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
2125 flags |= extent_op->flags_to_set;
2126 ret = alloc_reserved_file_extent(trans, root,
2127 parent, ref_root, flags,
2128 ref->objectid, ref->offset,
2129 &ins, node->ref_mod);
2130 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
2131 ret = __btrfs_inc_extent_ref(trans, root, node, parent,
2132 ref_root, ref->objectid,
2133 ref->offset, node->ref_mod,
2135 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
2136 ret = __btrfs_free_extent(trans, root, node, parent,
2137 ref_root, ref->objectid,
2138 ref->offset, node->ref_mod,
2146 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
2147 struct extent_buffer *leaf,
2148 struct btrfs_extent_item *ei)
2150 u64 flags = btrfs_extent_flags(leaf, ei);
2151 if (extent_op->update_flags) {
2152 flags |= extent_op->flags_to_set;
2153 btrfs_set_extent_flags(leaf, ei, flags);
2156 if (extent_op->update_key) {
2157 struct btrfs_tree_block_info *bi;
2158 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK));
2159 bi = (struct btrfs_tree_block_info *)(ei + 1);
2160 btrfs_set_tree_block_key(leaf, bi, &extent_op->key);
2164 static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
2165 struct btrfs_root *root,
2166 struct btrfs_delayed_ref_node *node,
2167 struct btrfs_delayed_extent_op *extent_op)
2169 struct btrfs_key key;
2170 struct btrfs_path *path;
2171 struct btrfs_extent_item *ei;
2172 struct extent_buffer *leaf;
2176 int metadata = !extent_op->is_data;
2181 if (metadata && !btrfs_fs_incompat(root->fs_info, SKINNY_METADATA))
2184 path = btrfs_alloc_path();
2188 key.objectid = node->bytenr;
2191 key.type = BTRFS_METADATA_ITEM_KEY;
2192 key.offset = extent_op->level;
2194 key.type = BTRFS_EXTENT_ITEM_KEY;
2195 key.offset = node->num_bytes;
2200 path->leave_spinning = 1;
2201 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key,
2209 if (path->slots[0] > 0) {
2211 btrfs_item_key_to_cpu(path->nodes[0], &key,
2213 if (key.objectid == node->bytenr &&
2214 key.type == BTRFS_EXTENT_ITEM_KEY &&
2215 key.offset == node->num_bytes)
2219 btrfs_release_path(path);
2222 key.objectid = node->bytenr;
2223 key.offset = node->num_bytes;
2224 key.type = BTRFS_EXTENT_ITEM_KEY;
2233 leaf = path->nodes[0];
2234 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2235 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2236 if (item_size < sizeof(*ei)) {
2237 ret = convert_extent_item_v0(trans, root->fs_info->extent_root,
2243 leaf = path->nodes[0];
2244 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2247 BUG_ON(item_size < sizeof(*ei));
2248 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2249 __run_delayed_extent_op(extent_op, leaf, ei);
2251 btrfs_mark_buffer_dirty(leaf);
2253 btrfs_free_path(path);
2257 static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
2258 struct btrfs_root *root,
2259 struct btrfs_delayed_ref_node *node,
2260 struct btrfs_delayed_extent_op *extent_op,
2261 int insert_reserved)
2264 struct btrfs_delayed_tree_ref *ref;
2265 struct btrfs_key ins;
2268 bool skinny_metadata = btrfs_fs_incompat(root->fs_info,
2271 ref = btrfs_delayed_node_to_tree_ref(node);
2272 trace_run_delayed_tree_ref(node, ref, node->action);
2274 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2275 parent = ref->parent;
2276 ref_root = ref->root;
2278 ins.objectid = node->bytenr;
2279 if (skinny_metadata) {
2280 ins.offset = ref->level;
2281 ins.type = BTRFS_METADATA_ITEM_KEY;
2283 ins.offset = node->num_bytes;
2284 ins.type = BTRFS_EXTENT_ITEM_KEY;
2287 BUG_ON(node->ref_mod != 1);
2288 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
2289 BUG_ON(!extent_op || !extent_op->update_flags);
2290 ret = alloc_reserved_tree_block(trans, root,
2292 extent_op->flags_to_set,
2296 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
2297 ret = __btrfs_inc_extent_ref(trans, root, node,
2301 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
2302 ret = __btrfs_free_extent(trans, root, node,
2304 ref->level, 0, 1, extent_op);
2311 /* helper function to actually process a single delayed ref entry */
2312 static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
2313 struct btrfs_root *root,
2314 struct btrfs_delayed_ref_node *node,
2315 struct btrfs_delayed_extent_op *extent_op,
2316 int insert_reserved)
2320 if (trans->aborted) {
2321 if (insert_reserved)
2322 btrfs_pin_extent(root, node->bytenr,
2323 node->num_bytes, 1);
2327 if (btrfs_delayed_ref_is_head(node)) {
2328 struct btrfs_delayed_ref_head *head;
2330 * we've hit the end of the chain and we were supposed
2331 * to insert this extent into the tree. But, it got
2332 * deleted before we ever needed to insert it, so all
2333 * we have to do is clean up the accounting
2336 head = btrfs_delayed_node_to_head(node);
2337 trace_run_delayed_ref_head(node, head, node->action);
2339 if (insert_reserved) {
2340 btrfs_pin_extent(root, node->bytenr,
2341 node->num_bytes, 1);
2342 if (head->is_data) {
2343 ret = btrfs_del_csums(trans, root,
2349 /* Also free its reserved qgroup space */
2350 btrfs_qgroup_free_delayed_ref(root->fs_info,
2351 head->qgroup_ref_root,
2352 head->qgroup_reserved);
2356 if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
2357 node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2358 ret = run_delayed_tree_ref(trans, root, node, extent_op,
2360 else if (node->type == BTRFS_EXTENT_DATA_REF_KEY ||
2361 node->type == BTRFS_SHARED_DATA_REF_KEY)
2362 ret = run_delayed_data_ref(trans, root, node, extent_op,
2369 static inline struct btrfs_delayed_ref_node *
2370 select_delayed_ref(struct btrfs_delayed_ref_head *head)
2372 struct btrfs_delayed_ref_node *ref;
2374 if (list_empty(&head->ref_list))
2378 * Select a delayed ref of type BTRFS_ADD_DELAYED_REF first.
2379 * This is to prevent a ref count from going down to zero, which deletes
2380 * the extent item from the extent tree, when there still are references
2381 * to add, which would fail because they would not find the extent item.
2383 list_for_each_entry(ref, &head->ref_list, list) {
2384 if (ref->action == BTRFS_ADD_DELAYED_REF)
2388 return list_entry(head->ref_list.next, struct btrfs_delayed_ref_node,
2393 * Returns 0 on success or if called with an already aborted transaction.
2394 * Returns -ENOMEM or -EIO on failure and will abort the transaction.
2396 static noinline int __btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2397 struct btrfs_root *root,
2400 struct btrfs_delayed_ref_root *delayed_refs;
2401 struct btrfs_delayed_ref_node *ref;
2402 struct btrfs_delayed_ref_head *locked_ref = NULL;
2403 struct btrfs_delayed_extent_op *extent_op;
2404 struct btrfs_fs_info *fs_info = root->fs_info;
2405 ktime_t start = ktime_get();
2407 unsigned long count = 0;
2408 unsigned long actual_count = 0;
2409 int must_insert_reserved = 0;
2411 delayed_refs = &trans->transaction->delayed_refs;
2417 spin_lock(&delayed_refs->lock);
2418 locked_ref = btrfs_select_ref_head(trans);
2420 spin_unlock(&delayed_refs->lock);
2424 /* grab the lock that says we are going to process
2425 * all the refs for this head */
2426 ret = btrfs_delayed_ref_lock(trans, locked_ref);
2427 spin_unlock(&delayed_refs->lock);
2429 * we may have dropped the spin lock to get the head
2430 * mutex lock, and that might have given someone else
2431 * time to free the head. If that's true, it has been
2432 * removed from our list and we can move on.
2434 if (ret == -EAGAIN) {
2441 spin_lock(&locked_ref->lock);
2444 * locked_ref is the head node, so we have to go one
2445 * node back for any delayed ref updates
2447 ref = select_delayed_ref(locked_ref);
2449 if (ref && ref->seq &&
2450 btrfs_check_delayed_seq(fs_info, delayed_refs, ref->seq)) {
2451 spin_unlock(&locked_ref->lock);
2452 btrfs_delayed_ref_unlock(locked_ref);
2453 spin_lock(&delayed_refs->lock);
2454 locked_ref->processing = 0;
2455 delayed_refs->num_heads_ready++;
2456 spin_unlock(&delayed_refs->lock);
2464 * record the must insert reserved flag before we
2465 * drop the spin lock.
2467 must_insert_reserved = locked_ref->must_insert_reserved;
2468 locked_ref->must_insert_reserved = 0;
2470 extent_op = locked_ref->extent_op;
2471 locked_ref->extent_op = NULL;
2476 /* All delayed refs have been processed, Go ahead
2477 * and send the head node to run_one_delayed_ref,
2478 * so that any accounting fixes can happen
2480 ref = &locked_ref->node;
2482 if (extent_op && must_insert_reserved) {
2483 btrfs_free_delayed_extent_op(extent_op);
2488 spin_unlock(&locked_ref->lock);
2489 ret = run_delayed_extent_op(trans, root,
2491 btrfs_free_delayed_extent_op(extent_op);
2495 * Need to reset must_insert_reserved if
2496 * there was an error so the abort stuff
2497 * can cleanup the reserved space
2500 if (must_insert_reserved)
2501 locked_ref->must_insert_reserved = 1;
2502 locked_ref->processing = 0;
2503 btrfs_debug(fs_info, "run_delayed_extent_op returned %d", ret);
2504 btrfs_delayed_ref_unlock(locked_ref);
2511 * Need to drop our head ref lock and re-aqcuire the
2512 * delayed ref lock and then re-check to make sure
2515 spin_unlock(&locked_ref->lock);
2516 spin_lock(&delayed_refs->lock);
2517 spin_lock(&locked_ref->lock);
2518 if (!list_empty(&locked_ref->ref_list) ||
2519 locked_ref->extent_op) {
2520 spin_unlock(&locked_ref->lock);
2521 spin_unlock(&delayed_refs->lock);
2525 delayed_refs->num_heads--;
2526 rb_erase(&locked_ref->href_node,
2527 &delayed_refs->href_root);
2528 spin_unlock(&delayed_refs->lock);
2532 list_del(&ref->list);
2534 atomic_dec(&delayed_refs->num_entries);
2536 if (!btrfs_delayed_ref_is_head(ref)) {
2538 * when we play the delayed ref, also correct the
2541 switch (ref->action) {
2542 case BTRFS_ADD_DELAYED_REF:
2543 case BTRFS_ADD_DELAYED_EXTENT:
2544 locked_ref->node.ref_mod -= ref->ref_mod;
2546 case BTRFS_DROP_DELAYED_REF:
2547 locked_ref->node.ref_mod += ref->ref_mod;
2553 spin_unlock(&locked_ref->lock);
2555 ret = run_one_delayed_ref(trans, root, ref, extent_op,
2556 must_insert_reserved);
2558 btrfs_free_delayed_extent_op(extent_op);
2560 locked_ref->processing = 0;
2561 btrfs_delayed_ref_unlock(locked_ref);
2562 btrfs_put_delayed_ref(ref);
2563 btrfs_debug(fs_info, "run_one_delayed_ref returned %d", ret);
2568 * If this node is a head, that means all the refs in this head
2569 * have been dealt with, and we will pick the next head to deal
2570 * with, so we must unlock the head and drop it from the cluster
2571 * list before we release it.
2573 if (btrfs_delayed_ref_is_head(ref)) {
2574 if (locked_ref->is_data &&
2575 locked_ref->total_ref_mod < 0) {
2576 spin_lock(&delayed_refs->lock);
2577 delayed_refs->pending_csums -= ref->num_bytes;
2578 spin_unlock(&delayed_refs->lock);
2580 btrfs_delayed_ref_unlock(locked_ref);
2583 btrfs_put_delayed_ref(ref);
2589 * We don't want to include ref heads since we can have empty ref heads
2590 * and those will drastically skew our runtime down since we just do
2591 * accounting, no actual extent tree updates.
2593 if (actual_count > 0) {
2594 u64 runtime = ktime_to_ns(ktime_sub(ktime_get(), start));
2598 * We weigh the current average higher than our current runtime
2599 * to avoid large swings in the average.
2601 spin_lock(&delayed_refs->lock);
2602 avg = fs_info->avg_delayed_ref_runtime * 3 + runtime;
2603 fs_info->avg_delayed_ref_runtime = avg >> 2; /* div by 4 */
2604 spin_unlock(&delayed_refs->lock);
2609 #ifdef SCRAMBLE_DELAYED_REFS
2611 * Normally delayed refs get processed in ascending bytenr order. This
2612 * correlates in most cases to the order added. To expose dependencies on this
2613 * order, we start to process the tree in the middle instead of the beginning
2615 static u64 find_middle(struct rb_root *root)
2617 struct rb_node *n = root->rb_node;
2618 struct btrfs_delayed_ref_node *entry;
2621 u64 first = 0, last = 0;
2625 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2626 first = entry->bytenr;
2630 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2631 last = entry->bytenr;
2636 entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node);
2637 WARN_ON(!entry->in_tree);
2639 middle = entry->bytenr;
2652 static inline u64 heads_to_leaves(struct btrfs_root *root, u64 heads)
2656 num_bytes = heads * (sizeof(struct btrfs_extent_item) +
2657 sizeof(struct btrfs_extent_inline_ref));
2658 if (!btrfs_fs_incompat(root->fs_info, SKINNY_METADATA))
2659 num_bytes += heads * sizeof(struct btrfs_tree_block_info);
2662 * We don't ever fill up leaves all the way so multiply by 2 just to be
2663 * closer to what we're really going to want to ouse.
2665 return div_u64(num_bytes, BTRFS_LEAF_DATA_SIZE(root));
2669 * Takes the number of bytes to be csumm'ed and figures out how many leaves it
2670 * would require to store the csums for that many bytes.
2672 u64 btrfs_csum_bytes_to_leaves(struct btrfs_root *root, u64 csum_bytes)
2675 u64 num_csums_per_leaf;
2678 csum_size = BTRFS_LEAF_DATA_SIZE(root) - sizeof(struct btrfs_item);
2679 num_csums_per_leaf = div64_u64(csum_size,
2680 (u64)btrfs_super_csum_size(root->fs_info->super_copy));
2681 num_csums = div64_u64(csum_bytes, root->sectorsize);
2682 num_csums += num_csums_per_leaf - 1;
2683 num_csums = div64_u64(num_csums, num_csums_per_leaf);
2687 int btrfs_check_space_for_delayed_refs(struct btrfs_trans_handle *trans,
2688 struct btrfs_root *root)
2690 struct btrfs_block_rsv *global_rsv;
2691 u64 num_heads = trans->transaction->delayed_refs.num_heads_ready;
2692 u64 csum_bytes = trans->transaction->delayed_refs.pending_csums;
2693 u64 num_dirty_bgs = trans->transaction->num_dirty_bgs;
2694 u64 num_bytes, num_dirty_bgs_bytes;
2697 num_bytes = btrfs_calc_trans_metadata_size(root, 1);
2698 num_heads = heads_to_leaves(root, num_heads);
2700 num_bytes += (num_heads - 1) * root->nodesize;
2702 num_bytes += btrfs_csum_bytes_to_leaves(root, csum_bytes) * root->nodesize;
2703 num_dirty_bgs_bytes = btrfs_calc_trans_metadata_size(root,
2705 global_rsv = &root->fs_info->global_block_rsv;
2708 * If we can't allocate any more chunks lets make sure we have _lots_ of
2709 * wiggle room since running delayed refs can create more delayed refs.
2711 if (global_rsv->space_info->full) {
2712 num_dirty_bgs_bytes <<= 1;
2716 spin_lock(&global_rsv->lock);
2717 if (global_rsv->reserved <= num_bytes + num_dirty_bgs_bytes)
2719 spin_unlock(&global_rsv->lock);
2723 int btrfs_should_throttle_delayed_refs(struct btrfs_trans_handle *trans,
2724 struct btrfs_root *root)
2726 struct btrfs_fs_info *fs_info = root->fs_info;
2728 atomic_read(&trans->transaction->delayed_refs.num_entries);
2733 avg_runtime = fs_info->avg_delayed_ref_runtime;
2734 val = num_entries * avg_runtime;
2735 if (num_entries * avg_runtime >= NSEC_PER_SEC)
2737 if (val >= NSEC_PER_SEC / 2)
2740 return btrfs_check_space_for_delayed_refs(trans, root);
2743 struct async_delayed_refs {
2744 struct btrfs_root *root;
2748 struct completion wait;
2749 struct btrfs_work work;
2752 static void delayed_ref_async_start(struct btrfs_work *work)
2754 struct async_delayed_refs *async;
2755 struct btrfs_trans_handle *trans;
2758 async = container_of(work, struct async_delayed_refs, work);
2760 trans = btrfs_join_transaction(async->root);
2761 if (IS_ERR(trans)) {
2762 async->error = PTR_ERR(trans);
2767 * trans->sync means that when we call end_transaciton, we won't
2768 * wait on delayed refs
2771 ret = btrfs_run_delayed_refs(trans, async->root, async->count);
2775 ret = btrfs_end_transaction(trans, async->root);
2776 if (ret && !async->error)
2780 complete(&async->wait);
2785 int btrfs_async_run_delayed_refs(struct btrfs_root *root,
2786 unsigned long count, int wait)
2788 struct async_delayed_refs *async;
2791 async = kmalloc(sizeof(*async), GFP_NOFS);
2795 async->root = root->fs_info->tree_root;
2796 async->count = count;
2802 init_completion(&async->wait);
2804 btrfs_init_work(&async->work, btrfs_extent_refs_helper,
2805 delayed_ref_async_start, NULL, NULL);
2807 btrfs_queue_work(root->fs_info->extent_workers, &async->work);
2810 wait_for_completion(&async->wait);
2819 * this starts processing the delayed reference count updates and
2820 * extent insertions we have queued up so far. count can be
2821 * 0, which means to process everything in the tree at the start
2822 * of the run (but not newly added entries), or it can be some target
2823 * number you'd like to process.
2825 * Returns 0 on success or if called with an aborted transaction
2826 * Returns <0 on error and aborts the transaction
2828 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2829 struct btrfs_root *root, unsigned long count)
2831 struct rb_node *node;
2832 struct btrfs_delayed_ref_root *delayed_refs;
2833 struct btrfs_delayed_ref_head *head;
2835 int run_all = count == (unsigned long)-1;
2836 bool can_flush_pending_bgs = trans->can_flush_pending_bgs;
2838 /* We'll clean this up in btrfs_cleanup_transaction */
2842 if (root == root->fs_info->extent_root)
2843 root = root->fs_info->tree_root;
2845 delayed_refs = &trans->transaction->delayed_refs;
2847 count = atomic_read(&delayed_refs->num_entries) * 2;
2850 #ifdef SCRAMBLE_DELAYED_REFS
2851 delayed_refs->run_delayed_start = find_middle(&delayed_refs->root);
2853 trans->can_flush_pending_bgs = false;
2854 ret = __btrfs_run_delayed_refs(trans, root, count);
2856 btrfs_abort_transaction(trans, root, ret);
2861 if (!list_empty(&trans->new_bgs))
2862 btrfs_create_pending_block_groups(trans, root);
2864 spin_lock(&delayed_refs->lock);
2865 node = rb_first(&delayed_refs->href_root);
2867 spin_unlock(&delayed_refs->lock);
2870 count = (unsigned long)-1;
2873 head = rb_entry(node, struct btrfs_delayed_ref_head,
2875 if (btrfs_delayed_ref_is_head(&head->node)) {
2876 struct btrfs_delayed_ref_node *ref;
2879 atomic_inc(&ref->refs);
2881 spin_unlock(&delayed_refs->lock);
2883 * Mutex was contended, block until it's
2884 * released and try again
2886 mutex_lock(&head->mutex);
2887 mutex_unlock(&head->mutex);
2889 btrfs_put_delayed_ref(ref);
2895 node = rb_next(node);
2897 spin_unlock(&delayed_refs->lock);
2902 assert_qgroups_uptodate(trans);
2903 trans->can_flush_pending_bgs = can_flush_pending_bgs;
2907 int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
2908 struct btrfs_root *root,
2909 u64 bytenr, u64 num_bytes, u64 flags,
2910 int level, int is_data)
2912 struct btrfs_delayed_extent_op *extent_op;
2915 extent_op = btrfs_alloc_delayed_extent_op();
2919 extent_op->flags_to_set = flags;
2920 extent_op->update_flags = 1;
2921 extent_op->update_key = 0;
2922 extent_op->is_data = is_data ? 1 : 0;
2923 extent_op->level = level;
2925 ret = btrfs_add_delayed_extent_op(root->fs_info, trans, bytenr,
2926 num_bytes, extent_op);
2928 btrfs_free_delayed_extent_op(extent_op);
2932 static noinline int check_delayed_ref(struct btrfs_trans_handle *trans,
2933 struct btrfs_root *root,
2934 struct btrfs_path *path,
2935 u64 objectid, u64 offset, u64 bytenr)
2937 struct btrfs_delayed_ref_head *head;
2938 struct btrfs_delayed_ref_node *ref;
2939 struct btrfs_delayed_data_ref *data_ref;
2940 struct btrfs_delayed_ref_root *delayed_refs;
2943 delayed_refs = &trans->transaction->delayed_refs;
2944 spin_lock(&delayed_refs->lock);
2945 head = btrfs_find_delayed_ref_head(trans, bytenr);
2947 spin_unlock(&delayed_refs->lock);
2951 if (!mutex_trylock(&head->mutex)) {
2952 atomic_inc(&head->node.refs);
2953 spin_unlock(&delayed_refs->lock);
2955 btrfs_release_path(path);
2958 * Mutex was contended, block until it's released and let
2961 mutex_lock(&head->mutex);
2962 mutex_unlock(&head->mutex);
2963 btrfs_put_delayed_ref(&head->node);
2966 spin_unlock(&delayed_refs->lock);
2968 spin_lock(&head->lock);
2969 list_for_each_entry(ref, &head->ref_list, list) {
2970 /* If it's a shared ref we know a cross reference exists */
2971 if (ref->type != BTRFS_EXTENT_DATA_REF_KEY) {
2976 data_ref = btrfs_delayed_node_to_data_ref(ref);
2979 * If our ref doesn't match the one we're currently looking at
2980 * then we have a cross reference.
2982 if (data_ref->root != root->root_key.objectid ||
2983 data_ref->objectid != objectid ||
2984 data_ref->offset != offset) {
2989 spin_unlock(&head->lock);
2990 mutex_unlock(&head->mutex);
2994 static noinline int check_committed_ref(struct btrfs_trans_handle *trans,
2995 struct btrfs_root *root,
2996 struct btrfs_path *path,
2997 u64 objectid, u64 offset, u64 bytenr)
2999 struct btrfs_root *extent_root = root->fs_info->extent_root;
3000 struct extent_buffer *leaf;
3001 struct btrfs_extent_data_ref *ref;
3002 struct btrfs_extent_inline_ref *iref;
3003 struct btrfs_extent_item *ei;
3004 struct btrfs_key key;
3008 key.objectid = bytenr;
3009 key.offset = (u64)-1;
3010 key.type = BTRFS_EXTENT_ITEM_KEY;
3012 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
3015 BUG_ON(ret == 0); /* Corruption */
3018 if (path->slots[0] == 0)
3022 leaf = path->nodes[0];
3023 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
3025 if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY)
3029 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
3030 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
3031 if (item_size < sizeof(*ei)) {
3032 WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0));
3036 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
3038 if (item_size != sizeof(*ei) +
3039 btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY))
3042 if (btrfs_extent_generation(leaf, ei) <=
3043 btrfs_root_last_snapshot(&root->root_item))
3046 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
3047 if (btrfs_extent_inline_ref_type(leaf, iref) !=
3048 BTRFS_EXTENT_DATA_REF_KEY)
3051 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
3052 if (btrfs_extent_refs(leaf, ei) !=
3053 btrfs_extent_data_ref_count(leaf, ref) ||
3054 btrfs_extent_data_ref_root(leaf, ref) !=
3055 root->root_key.objectid ||
3056 btrfs_extent_data_ref_objectid(leaf, ref) != objectid ||
3057 btrfs_extent_data_ref_offset(leaf, ref) != offset)
3065 int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans,
3066 struct btrfs_root *root,
3067 u64 objectid, u64 offset, u64 bytenr)
3069 struct btrfs_path *path;
3073 path = btrfs_alloc_path();
3078 ret = check_committed_ref(trans, root, path, objectid,
3080 if (ret && ret != -ENOENT)
3083 ret2 = check_delayed_ref(trans, root, path, objectid,
3085 } while (ret2 == -EAGAIN);
3087 if (ret2 && ret2 != -ENOENT) {
3092 if (ret != -ENOENT || ret2 != -ENOENT)
3095 btrfs_free_path(path);
3096 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
3101 static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
3102 struct btrfs_root *root,
3103 struct extent_buffer *buf,
3104 int full_backref, int inc)
3111 struct btrfs_key key;
3112 struct btrfs_file_extent_item *fi;
3116 int (*process_func)(struct btrfs_trans_handle *, struct btrfs_root *,
3117 u64, u64, u64, u64, u64, u64, int);
3120 if (btrfs_test_is_dummy_root(root))
3123 ref_root = btrfs_header_owner(buf);
3124 nritems = btrfs_header_nritems(buf);
3125 level = btrfs_header_level(buf);
3127 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state) && level == 0)
3131 process_func = btrfs_inc_extent_ref;
3133 process_func = btrfs_free_extent;
3136 parent = buf->start;
3140 for (i = 0; i < nritems; i++) {
3142 btrfs_item_key_to_cpu(buf, &key, i);
3143 if (key.type != BTRFS_EXTENT_DATA_KEY)
3145 fi = btrfs_item_ptr(buf, i,
3146 struct btrfs_file_extent_item);
3147 if (btrfs_file_extent_type(buf, fi) ==
3148 BTRFS_FILE_EXTENT_INLINE)
3150 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
3154 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
3155 key.offset -= btrfs_file_extent_offset(buf, fi);
3156 ret = process_func(trans, root, bytenr, num_bytes,
3157 parent, ref_root, key.objectid,
3162 bytenr = btrfs_node_blockptr(buf, i);
3163 num_bytes = root->nodesize;
3164 ret = process_func(trans, root, bytenr, num_bytes,
3165 parent, ref_root, level - 1, 0,
3176 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
3177 struct extent_buffer *buf, int full_backref)
3179 return __btrfs_mod_ref(trans, root, buf, full_backref, 1);
3182 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
3183 struct extent_buffer *buf, int full_backref)
3185 return __btrfs_mod_ref(trans, root, buf, full_backref, 0);
3188 static int write_one_cache_group(struct btrfs_trans_handle *trans,
3189 struct btrfs_root *root,
3190 struct btrfs_path *path,
3191 struct btrfs_block_group_cache *cache)
3194 struct btrfs_root *extent_root = root->fs_info->extent_root;
3196 struct extent_buffer *leaf;
3198 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
3205 leaf = path->nodes[0];
3206 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
3207 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
3208 btrfs_mark_buffer_dirty(leaf);
3210 btrfs_release_path(path);
3215 static struct btrfs_block_group_cache *
3216 next_block_group(struct btrfs_root *root,
3217 struct btrfs_block_group_cache *cache)
3219 struct rb_node *node;
3221 spin_lock(&root->fs_info->block_group_cache_lock);
3223 /* If our block group was removed, we need a full search. */
3224 if (RB_EMPTY_NODE(&cache->cache_node)) {
3225 const u64 next_bytenr = cache->key.objectid + cache->key.offset;
3227 spin_unlock(&root->fs_info->block_group_cache_lock);
3228 btrfs_put_block_group(cache);
3229 cache = btrfs_lookup_first_block_group(root->fs_info,
3233 node = rb_next(&cache->cache_node);
3234 btrfs_put_block_group(cache);
3236 cache = rb_entry(node, struct btrfs_block_group_cache,
3238 btrfs_get_block_group(cache);
3241 spin_unlock(&root->fs_info->block_group_cache_lock);
3245 static int cache_save_setup(struct btrfs_block_group_cache *block_group,
3246 struct btrfs_trans_handle *trans,
3247 struct btrfs_path *path)
3249 struct btrfs_root *root = block_group->fs_info->tree_root;
3250 struct inode *inode = NULL;
3252 int dcs = BTRFS_DC_ERROR;
3258 * If this block group is smaller than 100 megs don't bother caching the
3261 if (block_group->key.offset < (100 * 1024 * 1024)) {
3262 spin_lock(&block_group->lock);
3263 block_group->disk_cache_state = BTRFS_DC_WRITTEN;
3264 spin_unlock(&block_group->lock);
3271 inode = lookup_free_space_inode(root, block_group, path);
3272 if (IS_ERR(inode) && PTR_ERR(inode) != -ENOENT) {
3273 ret = PTR_ERR(inode);
3274 btrfs_release_path(path);
3278 if (IS_ERR(inode)) {
3282 if (block_group->ro)
3285 ret = create_free_space_inode(root, trans, block_group, path);
3291 /* We've already setup this transaction, go ahead and exit */
3292 if (block_group->cache_generation == trans->transid &&
3293 i_size_read(inode)) {
3294 dcs = BTRFS_DC_SETUP;
3299 * We want to set the generation to 0, that way if anything goes wrong
3300 * from here on out we know not to trust this cache when we load up next
3303 BTRFS_I(inode)->generation = 0;
3304 ret = btrfs_update_inode(trans, root, inode);
3307 * So theoretically we could recover from this, simply set the
3308 * super cache generation to 0 so we know to invalidate the
3309 * cache, but then we'd have to keep track of the block groups
3310 * that fail this way so we know we _have_ to reset this cache
3311 * before the next commit or risk reading stale cache. So to
3312 * limit our exposure to horrible edge cases lets just abort the
3313 * transaction, this only happens in really bad situations
3316 btrfs_abort_transaction(trans, root, ret);
3321 if (i_size_read(inode) > 0) {
3322 ret = btrfs_check_trunc_cache_free_space(root,
3323 &root->fs_info->global_block_rsv);
3327 ret = btrfs_truncate_free_space_cache(root, trans, NULL, inode);
3332 spin_lock(&block_group->lock);
3333 if (block_group->cached != BTRFS_CACHE_FINISHED ||
3334 !btrfs_test_opt(root, SPACE_CACHE)) {
3336 * don't bother trying to write stuff out _if_
3337 * a) we're not cached,
3338 * b) we're with nospace_cache mount option.
3340 dcs = BTRFS_DC_WRITTEN;
3341 spin_unlock(&block_group->lock);
3344 spin_unlock(&block_group->lock);
3347 * Try to preallocate enough space based on how big the block group is.
3348 * Keep in mind this has to include any pinned space which could end up
3349 * taking up quite a bit since it's not folded into the other space
3352 num_pages = div_u64(block_group->key.offset, 256 * 1024 * 1024);
3357 num_pages *= PAGE_CACHE_SIZE;
3359 ret = __btrfs_check_data_free_space(inode, 0, num_pages);
3363 ret = btrfs_prealloc_file_range_trans(inode, trans, 0, 0, num_pages,
3364 num_pages, num_pages,
3367 dcs = BTRFS_DC_SETUP;
3368 __btrfs_free_reserved_data_space(inode, 0, num_pages);
3373 btrfs_release_path(path);
3375 spin_lock(&block_group->lock);
3376 if (!ret && dcs == BTRFS_DC_SETUP)
3377 block_group->cache_generation = trans->transid;
3378 block_group->disk_cache_state = dcs;
3379 spin_unlock(&block_group->lock);
3384 int btrfs_setup_space_cache(struct btrfs_trans_handle *trans,
3385 struct btrfs_root *root)
3387 struct btrfs_block_group_cache *cache, *tmp;
3388 struct btrfs_transaction *cur_trans = trans->transaction;
3389 struct btrfs_path *path;
3391 if (list_empty(&cur_trans->dirty_bgs) ||
3392 !btrfs_test_opt(root, SPACE_CACHE))
3395 path = btrfs_alloc_path();
3399 /* Could add new block groups, use _safe just in case */
3400 list_for_each_entry_safe(cache, tmp, &cur_trans->dirty_bgs,
3402 if (cache->disk_cache_state == BTRFS_DC_CLEAR)
3403 cache_save_setup(cache, trans, path);
3406 btrfs_free_path(path);
3411 * transaction commit does final block group cache writeback during a
3412 * critical section where nothing is allowed to change the FS. This is
3413 * required in order for the cache to actually match the block group,
3414 * but can introduce a lot of latency into the commit.
3416 * So, btrfs_start_dirty_block_groups is here to kick off block group
3417 * cache IO. There's a chance we'll have to redo some of it if the
3418 * block group changes again during the commit, but it greatly reduces
3419 * the commit latency by getting rid of the easy block groups while
3420 * we're still allowing others to join the commit.
3422 int btrfs_start_dirty_block_groups(struct btrfs_trans_handle *trans,
3423 struct btrfs_root *root)
3425 struct btrfs_block_group_cache *cache;
3426 struct btrfs_transaction *cur_trans = trans->transaction;
3429 struct btrfs_path *path = NULL;
3431 struct list_head *io = &cur_trans->io_bgs;
3432 int num_started = 0;
3435 spin_lock(&cur_trans->dirty_bgs_lock);
3436 if (list_empty(&cur_trans->dirty_bgs)) {
3437 spin_unlock(&cur_trans->dirty_bgs_lock);
3440 list_splice_init(&cur_trans->dirty_bgs, &dirty);
3441 spin_unlock(&cur_trans->dirty_bgs_lock);
3445 * make sure all the block groups on our dirty list actually
3448 btrfs_create_pending_block_groups(trans, root);
3451 path = btrfs_alloc_path();
3457 * cache_write_mutex is here only to save us from balance or automatic
3458 * removal of empty block groups deleting this block group while we are
3459 * writing out the cache
3461 mutex_lock(&trans->transaction->cache_write_mutex);
3462 while (!list_empty(&dirty)) {
3463 cache = list_first_entry(&dirty,
3464 struct btrfs_block_group_cache,
3467 * this can happen if something re-dirties a block
3468 * group that is already under IO. Just wait for it to
3469 * finish and then do it all again
3471 if (!list_empty(&cache->io_list)) {
3472 list_del_init(&cache->io_list);
3473 btrfs_wait_cache_io(root, trans, cache,
3474 &cache->io_ctl, path,
3475 cache->key.objectid);
3476 btrfs_put_block_group(cache);
3481 * btrfs_wait_cache_io uses the cache->dirty_list to decide
3482 * if it should update the cache_state. Don't delete
3483 * until after we wait.
3485 * Since we're not running in the commit critical section
3486 * we need the dirty_bgs_lock to protect from update_block_group
3488 spin_lock(&cur_trans->dirty_bgs_lock);
3489 list_del_init(&cache->dirty_list);
3490 spin_unlock(&cur_trans->dirty_bgs_lock);
3494 cache_save_setup(cache, trans, path);
3496 if (cache->disk_cache_state == BTRFS_DC_SETUP) {
3497 cache->io_ctl.inode = NULL;
3498 ret = btrfs_write_out_cache(root, trans, cache, path);
3499 if (ret == 0 && cache->io_ctl.inode) {
3504 * the cache_write_mutex is protecting
3507 list_add_tail(&cache->io_list, io);
3510 * if we failed to write the cache, the
3511 * generation will be bad and life goes on
3517 ret = write_one_cache_group(trans, root, path, cache);
3519 * Our block group might still be attached to the list
3520 * of new block groups in the transaction handle of some
3521 * other task (struct btrfs_trans_handle->new_bgs). This
3522 * means its block group item isn't yet in the extent
3523 * tree. If this happens ignore the error, as we will
3524 * try again later in the critical section of the
3525 * transaction commit.
3527 if (ret == -ENOENT) {
3529 spin_lock(&cur_trans->dirty_bgs_lock);
3530 if (list_empty(&cache->dirty_list)) {
3531 list_add_tail(&cache->dirty_list,
3532 &cur_trans->dirty_bgs);
3533 btrfs_get_block_group(cache);
3535 spin_unlock(&cur_trans->dirty_bgs_lock);
3537 btrfs_abort_transaction(trans, root, ret);
3541 /* if its not on the io list, we need to put the block group */
3543 btrfs_put_block_group(cache);
3549 * Avoid blocking other tasks for too long. It might even save
3550 * us from writing caches for block groups that are going to be
3553 mutex_unlock(&trans->transaction->cache_write_mutex);
3554 mutex_lock(&trans->transaction->cache_write_mutex);
3556 mutex_unlock(&trans->transaction->cache_write_mutex);
3559 * go through delayed refs for all the stuff we've just kicked off
3560 * and then loop back (just once)
3562 ret = btrfs_run_delayed_refs(trans, root, 0);
3563 if (!ret && loops == 0) {
3565 spin_lock(&cur_trans->dirty_bgs_lock);
3566 list_splice_init(&cur_trans->dirty_bgs, &dirty);
3568 * dirty_bgs_lock protects us from concurrent block group
3569 * deletes too (not just cache_write_mutex).
3571 if (!list_empty(&dirty)) {
3572 spin_unlock(&cur_trans->dirty_bgs_lock);
3575 spin_unlock(&cur_trans->dirty_bgs_lock);
3578 btrfs_free_path(path);
3582 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
3583 struct btrfs_root *root)
3585 struct btrfs_block_group_cache *cache;
3586 struct btrfs_transaction *cur_trans = trans->transaction;
3589 struct btrfs_path *path;
3590 struct list_head *io = &cur_trans->io_bgs;
3591 int num_started = 0;
3593 path = btrfs_alloc_path();
3598 * We don't need the lock here since we are protected by the transaction
3599 * commit. We want to do the cache_save_setup first and then run the
3600 * delayed refs to make sure we have the best chance at doing this all
3603 while (!list_empty(&cur_trans->dirty_bgs)) {
3604 cache = list_first_entry(&cur_trans->dirty_bgs,
3605 struct btrfs_block_group_cache,
3609 * this can happen if cache_save_setup re-dirties a block
3610 * group that is already under IO. Just wait for it to
3611 * finish and then do it all again
3613 if (!list_empty(&cache->io_list)) {
3614 list_del_init(&cache->io_list);
3615 btrfs_wait_cache_io(root, trans, cache,
3616 &cache->io_ctl, path,
3617 cache->key.objectid);
3618 btrfs_put_block_group(cache);
3622 * don't remove from the dirty list until after we've waited
3625 list_del_init(&cache->dirty_list);
3628 cache_save_setup(cache, trans, path);
3631 ret = btrfs_run_delayed_refs(trans, root, (unsigned long) -1);
3633 if (!ret && cache->disk_cache_state == BTRFS_DC_SETUP) {
3634 cache->io_ctl.inode = NULL;
3635 ret = btrfs_write_out_cache(root, trans, cache, path);
3636 if (ret == 0 && cache->io_ctl.inode) {
3639 list_add_tail(&cache->io_list, io);
3642 * if we failed to write the cache, the
3643 * generation will be bad and life goes on
3649 ret = write_one_cache_group(trans, root, path, cache);
3651 btrfs_abort_transaction(trans, root, ret);
3654 /* if its not on the io list, we need to put the block group */
3656 btrfs_put_block_group(cache);
3659 while (!list_empty(io)) {
3660 cache = list_first_entry(io, struct btrfs_block_group_cache,
3662 list_del_init(&cache->io_list);
3663 btrfs_wait_cache_io(root, trans, cache,
3664 &cache->io_ctl, path, cache->key.objectid);
3665 btrfs_put_block_group(cache);
3668 btrfs_free_path(path);
3672 int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr)
3674 struct btrfs_block_group_cache *block_group;
3677 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
3678 if (!block_group || block_group->ro)
3681 btrfs_put_block_group(block_group);
3685 static const char *alloc_name(u64 flags)
3688 case BTRFS_BLOCK_GROUP_METADATA|BTRFS_BLOCK_GROUP_DATA:
3690 case BTRFS_BLOCK_GROUP_METADATA:
3692 case BTRFS_BLOCK_GROUP_DATA:
3694 case BTRFS_BLOCK_GROUP_SYSTEM:
3698 return "invalid-combination";
3702 static int update_space_info(struct btrfs_fs_info *info, u64 flags,
3703 u64 total_bytes, u64 bytes_used,
3704 struct btrfs_space_info **space_info)
3706 struct btrfs_space_info *found;
3711 if (flags & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
3712 BTRFS_BLOCK_GROUP_RAID10))
3717 found = __find_space_info(info, flags);
3719 spin_lock(&found->lock);
3720 found->total_bytes += total_bytes;
3721 found->disk_total += total_bytes * factor;
3722 found->bytes_used += bytes_used;
3723 found->disk_used += bytes_used * factor;
3724 if (total_bytes > 0)
3726 spin_unlock(&found->lock);
3727 *space_info = found;
3730 found = kzalloc(sizeof(*found), GFP_NOFS);
3734 ret = percpu_counter_init(&found->total_bytes_pinned, 0, GFP_KERNEL);
3740 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
3741 INIT_LIST_HEAD(&found->block_groups[i]);
3742 init_rwsem(&found->groups_sem);
3743 spin_lock_init(&found->lock);
3744 found->flags = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
3745 found->total_bytes = total_bytes;
3746 found->disk_total = total_bytes * factor;
3747 found->bytes_used = bytes_used;
3748 found->disk_used = bytes_used * factor;
3749 found->bytes_pinned = 0;
3750 found->bytes_reserved = 0;
3751 found->bytes_readonly = 0;
3752 found->bytes_may_use = 0;
3754 found->force_alloc = CHUNK_ALLOC_NO_FORCE;
3755 found->chunk_alloc = 0;
3757 init_waitqueue_head(&found->wait);
3758 INIT_LIST_HEAD(&found->ro_bgs);
3760 ret = kobject_init_and_add(&found->kobj, &space_info_ktype,
3761 info->space_info_kobj, "%s",
3762 alloc_name(found->flags));
3768 *space_info = found;
3769 list_add_rcu(&found->list, &info->space_info);
3770 if (flags & BTRFS_BLOCK_GROUP_DATA)
3771 info->data_sinfo = found;
3776 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
3778 u64 extra_flags = chunk_to_extended(flags) &
3779 BTRFS_EXTENDED_PROFILE_MASK;
3781 write_seqlock(&fs_info->profiles_lock);
3782 if (flags & BTRFS_BLOCK_GROUP_DATA)
3783 fs_info->avail_data_alloc_bits |= extra_flags;
3784 if (flags & BTRFS_BLOCK_GROUP_METADATA)
3785 fs_info->avail_metadata_alloc_bits |= extra_flags;
3786 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
3787 fs_info->avail_system_alloc_bits |= extra_flags;
3788 write_sequnlock(&fs_info->profiles_lock);
3792 * returns target flags in extended format or 0 if restripe for this
3793 * chunk_type is not in progress
3795 * should be called with either volume_mutex or balance_lock held
3797 static u64 get_restripe_target(struct btrfs_fs_info *fs_info, u64 flags)
3799 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3805 if (flags & BTRFS_BLOCK_GROUP_DATA &&
3806 bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3807 target = BTRFS_BLOCK_GROUP_DATA | bctl->data.target;
3808 } else if (flags & BTRFS_BLOCK_GROUP_SYSTEM &&
3809 bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3810 target = BTRFS_BLOCK_GROUP_SYSTEM | bctl->sys.target;
3811 } else if (flags & BTRFS_BLOCK_GROUP_METADATA &&
3812 bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3813 target = BTRFS_BLOCK_GROUP_METADATA | bctl->meta.target;
3820 * @flags: available profiles in extended format (see ctree.h)
3822 * Returns reduced profile in chunk format. If profile changing is in
3823 * progress (either running or paused) picks the target profile (if it's
3824 * already available), otherwise falls back to plain reducing.
3826 static u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
3828 u64 num_devices = root->fs_info->fs_devices->rw_devices;
3834 * see if restripe for this chunk_type is in progress, if so
3835 * try to reduce to the target profile
3837 spin_lock(&root->fs_info->balance_lock);
3838 target = get_restripe_target(root->fs_info, flags);
3840 /* pick target profile only if it's already available */
3841 if ((flags & target) & BTRFS_EXTENDED_PROFILE_MASK) {
3842 spin_unlock(&root->fs_info->balance_lock);
3843 return extended_to_chunk(target);
3846 spin_unlock(&root->fs_info->balance_lock);
3848 /* First, mask out the RAID levels which aren't possible */
3849 for (raid_type = 0; raid_type < BTRFS_NR_RAID_TYPES; raid_type++) {
3850 if (num_devices >= btrfs_raid_array[raid_type].devs_min)
3851 allowed |= btrfs_raid_group[raid_type];
3855 if (allowed & BTRFS_BLOCK_GROUP_RAID6)
3856 allowed = BTRFS_BLOCK_GROUP_RAID6;
3857 else if (allowed & BTRFS_BLOCK_GROUP_RAID5)
3858 allowed = BTRFS_BLOCK_GROUP_RAID5;
3859 else if (allowed & BTRFS_BLOCK_GROUP_RAID10)
3860 allowed = BTRFS_BLOCK_GROUP_RAID10;
3861 else if (allowed & BTRFS_BLOCK_GROUP_RAID1)
3862 allowed = BTRFS_BLOCK_GROUP_RAID1;
3863 else if (allowed & BTRFS_BLOCK_GROUP_RAID0)
3864 allowed = BTRFS_BLOCK_GROUP_RAID0;
3866 flags &= ~BTRFS_BLOCK_GROUP_PROFILE_MASK;
3868 return extended_to_chunk(flags | allowed);
3871 static u64 get_alloc_profile(struct btrfs_root *root, u64 orig_flags)
3878 seq = read_seqbegin(&root->fs_info->profiles_lock);
3880 if (flags & BTRFS_BLOCK_GROUP_DATA)
3881 flags |= root->fs_info->avail_data_alloc_bits;
3882 else if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
3883 flags |= root->fs_info->avail_system_alloc_bits;
3884 else if (flags & BTRFS_BLOCK_GROUP_METADATA)
3885 flags |= root->fs_info->avail_metadata_alloc_bits;
3886 } while (read_seqretry(&root->fs_info->profiles_lock, seq));
3888 return btrfs_reduce_alloc_profile(root, flags);
3891 u64 btrfs_get_alloc_profile(struct btrfs_root *root, int data)
3897 flags = BTRFS_BLOCK_GROUP_DATA;
3898 else if (root == root->fs_info->chunk_root)
3899 flags = BTRFS_BLOCK_GROUP_SYSTEM;
3901 flags = BTRFS_BLOCK_GROUP_METADATA;
3903 ret = get_alloc_profile(root, flags);
3907 int btrfs_alloc_data_chunk_ondemand(struct inode *inode, u64 bytes)
3909 struct btrfs_space_info *data_sinfo;
3910 struct btrfs_root *root = BTRFS_I(inode)->root;
3911 struct btrfs_fs_info *fs_info = root->fs_info;
3914 int need_commit = 2;
3915 int have_pinned_space;
3917 /* make sure bytes are sectorsize aligned */
3918 bytes = ALIGN(bytes, root->sectorsize);
3920 if (btrfs_is_free_space_inode(inode)) {
3922 ASSERT(current->journal_info);
3925 data_sinfo = fs_info->data_sinfo;
3930 /* make sure we have enough space to handle the data first */
3931 spin_lock(&data_sinfo->lock);
3932 used = data_sinfo->bytes_used + data_sinfo->bytes_reserved +
3933 data_sinfo->bytes_pinned + data_sinfo->bytes_readonly +
3934 data_sinfo->bytes_may_use;
3936 if (used + bytes > data_sinfo->total_bytes) {
3937 struct btrfs_trans_handle *trans;
3940 * if we don't have enough free bytes in this space then we need
3941 * to alloc a new chunk.
3943 if (!data_sinfo->full) {
3946 data_sinfo->force_alloc = CHUNK_ALLOC_FORCE;
3947 spin_unlock(&data_sinfo->lock);
3949 alloc_target = btrfs_get_alloc_profile(root, 1);
3951 * It is ugly that we don't call nolock join
3952 * transaction for the free space inode case here.
3953 * But it is safe because we only do the data space
3954 * reservation for the free space cache in the
3955 * transaction context, the common join transaction
3956 * just increase the counter of the current transaction
3957 * handler, doesn't try to acquire the trans_lock of
3960 trans = btrfs_join_transaction(root);
3962 return PTR_ERR(trans);
3964 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
3966 CHUNK_ALLOC_NO_FORCE);
3967 btrfs_end_transaction(trans, root);
3972 have_pinned_space = 1;
3978 data_sinfo = fs_info->data_sinfo;
3984 * If we don't have enough pinned space to deal with this
3985 * allocation, and no removed chunk in current transaction,
3986 * don't bother committing the transaction.
3988 have_pinned_space = percpu_counter_compare(
3989 &data_sinfo->total_bytes_pinned,
3990 used + bytes - data_sinfo->total_bytes);
3991 spin_unlock(&data_sinfo->lock);
3993 /* commit the current transaction and try again */
3996 !atomic_read(&root->fs_info->open_ioctl_trans)) {
3999 if (need_commit > 0)
4000 btrfs_wait_ordered_roots(fs_info, -1);
4002 trans = btrfs_join_transaction(root);
4004 return PTR_ERR(trans);
4005 if (have_pinned_space >= 0 ||
4006 trans->transaction->have_free_bgs ||
4008 ret = btrfs_commit_transaction(trans, root);
4012 * make sure that all running delayed iput are
4015 down_write(&root->fs_info->delayed_iput_sem);
4016 up_write(&root->fs_info->delayed_iput_sem);
4019 btrfs_end_transaction(trans, root);
4023 trace_btrfs_space_reservation(root->fs_info,
4024 "space_info:enospc",
4025 data_sinfo->flags, bytes, 1);
4028 data_sinfo->bytes_may_use += bytes;
4029 trace_btrfs_space_reservation(root->fs_info, "space_info",
4030 data_sinfo->flags, bytes, 1);
4031 spin_unlock(&data_sinfo->lock);
4037 * This will check the space that the inode allocates from to make sure we have
4038 * enough space for bytes.
4040 int btrfs_check_data_free_space(struct inode *inode, u64 bytes, u64 write_bytes)
4042 struct btrfs_root *root = BTRFS_I(inode)->root;
4045 ret = btrfs_alloc_data_chunk_ondemand(inode, bytes);
4048 ret = btrfs_qgroup_reserve(root, write_bytes);
4053 * New check_data_free_space() with ability for precious data reservation
4054 * Will replace old btrfs_check_data_free_space(), but for patch split,
4055 * add a new function first and then replace it.
4057 int __btrfs_check_data_free_space(struct inode *inode, u64 start, u64 len)
4059 struct btrfs_root *root = BTRFS_I(inode)->root;
4062 /* align the range */
4063 len = round_up(start + len, root->sectorsize) -
4064 round_down(start, root->sectorsize);
4065 start = round_down(start, root->sectorsize);
4067 ret = btrfs_alloc_data_chunk_ondemand(inode, len);
4071 /* Use new btrfs_qgroup_reserve_data to reserve precious data space */
4072 ret = btrfs_qgroup_reserve_data(inode, start, len);
4077 * Called if we need to clear a data reservation for this inode.
4079 void btrfs_free_reserved_data_space(struct inode *inode, u64 bytes)
4081 struct btrfs_root *root = BTRFS_I(inode)->root;
4082 struct btrfs_space_info *data_sinfo;
4084 /* make sure bytes are sectorsize aligned */
4085 bytes = ALIGN(bytes, root->sectorsize);
4087 data_sinfo = root->fs_info->data_sinfo;
4088 spin_lock(&data_sinfo->lock);
4089 WARN_ON(data_sinfo->bytes_may_use < bytes);
4090 data_sinfo->bytes_may_use -= bytes;
4091 trace_btrfs_space_reservation(root->fs_info, "space_info",
4092 data_sinfo->flags, bytes, 0);
4093 spin_unlock(&data_sinfo->lock);
4097 * Called if we need to clear a data reservation for this inode
4098 * Normally in a error case.
4100 * This one will handle the per-indoe data rsv map for accurate reserved
4103 void __btrfs_free_reserved_data_space(struct inode *inode, u64 start, u64 len)
4105 struct btrfs_root *root = BTRFS_I(inode)->root;
4106 struct btrfs_space_info *data_sinfo;
4108 /* Make sure the range is aligned to sectorsize */
4109 len = round_up(start + len, root->sectorsize) -
4110 round_down(start, root->sectorsize);
4111 start = round_down(start, root->sectorsize);
4114 * Free any reserved qgroup data space first
4115 * As it will alloc memory, we can't do it with data sinfo
4118 btrfs_qgroup_free_data(inode, start, len);
4120 data_sinfo = root->fs_info->data_sinfo;
4121 spin_lock(&data_sinfo->lock);
4122 if (WARN_ON(data_sinfo->bytes_may_use < len))
4123 data_sinfo->bytes_may_use = 0;
4125 data_sinfo->bytes_may_use -= len;
4126 trace_btrfs_space_reservation(root->fs_info, "space_info",
4127 data_sinfo->flags, len, 0);
4128 spin_unlock(&data_sinfo->lock);
4131 static void force_metadata_allocation(struct btrfs_fs_info *info)
4133 struct list_head *head = &info->space_info;
4134 struct btrfs_space_info *found;
4137 list_for_each_entry_rcu(found, head, list) {
4138 if (found->flags & BTRFS_BLOCK_GROUP_METADATA)
4139 found->force_alloc = CHUNK_ALLOC_FORCE;
4144 static inline u64 calc_global_rsv_need_space(struct btrfs_block_rsv *global)
4146 return (global->size << 1);
4149 static int should_alloc_chunk(struct btrfs_root *root,
4150 struct btrfs_space_info *sinfo, int force)
4152 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
4153 u64 num_bytes = sinfo->total_bytes - sinfo->bytes_readonly;
4154 u64 num_allocated = sinfo->bytes_used + sinfo->bytes_reserved;
4157 if (force == CHUNK_ALLOC_FORCE)
4161 * We need to take into account the global rsv because for all intents
4162 * and purposes it's used space. Don't worry about locking the
4163 * global_rsv, it doesn't change except when the transaction commits.
4165 if (sinfo->flags & BTRFS_BLOCK_GROUP_METADATA)
4166 num_allocated += calc_global_rsv_need_space(global_rsv);
4169 * in limited mode, we want to have some free space up to
4170 * about 1% of the FS size.
4172 if (force == CHUNK_ALLOC_LIMITED) {
4173 thresh = btrfs_super_total_bytes(root->fs_info->super_copy);
4174 thresh = max_t(u64, 64 * 1024 * 1024,
4175 div_factor_fine(thresh, 1));
4177 if (num_bytes - num_allocated < thresh)
4181 if (num_allocated + 2 * 1024 * 1024 < div_factor(num_bytes, 8))
4186 static u64 get_profile_num_devs(struct btrfs_root *root, u64 type)
4190 if (type & (BTRFS_BLOCK_GROUP_RAID10 |
4191 BTRFS_BLOCK_GROUP_RAID0 |
4192 BTRFS_BLOCK_GROUP_RAID5 |
4193 BTRFS_BLOCK_GROUP_RAID6))
4194 num_dev = root->fs_info->fs_devices->rw_devices;
4195 else if (type & BTRFS_BLOCK_GROUP_RAID1)
4198 num_dev = 1; /* DUP or single */
4204 * If @is_allocation is true, reserve space in the system space info necessary
4205 * for allocating a chunk, otherwise if it's false, reserve space necessary for
4208 void check_system_chunk(struct btrfs_trans_handle *trans,
4209 struct btrfs_root *root,
4212 struct btrfs_space_info *info;
4219 * Needed because we can end up allocating a system chunk and for an
4220 * atomic and race free space reservation in the chunk block reserve.
4222 ASSERT(mutex_is_locked(&root->fs_info->chunk_mutex));
4224 info = __find_space_info(root->fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
4225 spin_lock(&info->lock);
4226 left = info->total_bytes - info->bytes_used - info->bytes_pinned -
4227 info->bytes_reserved - info->bytes_readonly -
4228 info->bytes_may_use;
4229 spin_unlock(&info->lock);
4231 num_devs = get_profile_num_devs(root, type);
4233 /* num_devs device items to update and 1 chunk item to add or remove */
4234 thresh = btrfs_calc_trunc_metadata_size(root, num_devs) +
4235 btrfs_calc_trans_metadata_size(root, 1);
4237 if (left < thresh && btrfs_test_opt(root, ENOSPC_DEBUG)) {
4238 btrfs_info(root->fs_info, "left=%llu, need=%llu, flags=%llu",
4239 left, thresh, type);
4240 dump_space_info(info, 0, 0);
4243 if (left < thresh) {
4246 flags = btrfs_get_alloc_profile(root->fs_info->chunk_root, 0);
4248 * Ignore failure to create system chunk. We might end up not
4249 * needing it, as we might not need to COW all nodes/leafs from
4250 * the paths we visit in the chunk tree (they were already COWed
4251 * or created in the current transaction for example).
4253 ret = btrfs_alloc_chunk(trans, root, flags);
4257 ret = btrfs_block_rsv_add(root->fs_info->chunk_root,
4258 &root->fs_info->chunk_block_rsv,
4259 thresh, BTRFS_RESERVE_NO_FLUSH);
4261 trans->chunk_bytes_reserved += thresh;
4265 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
4266 struct btrfs_root *extent_root, u64 flags, int force)
4268 struct btrfs_space_info *space_info;
4269 struct btrfs_fs_info *fs_info = extent_root->fs_info;
4270 int wait_for_alloc = 0;
4273 /* Don't re-enter if we're already allocating a chunk */
4274 if (trans->allocating_chunk)
4277 space_info = __find_space_info(extent_root->fs_info, flags);
4279 ret = update_space_info(extent_root->fs_info, flags,
4281 BUG_ON(ret); /* -ENOMEM */
4283 BUG_ON(!space_info); /* Logic error */
4286 spin_lock(&space_info->lock);
4287 if (force < space_info->force_alloc)
4288 force = space_info->force_alloc;
4289 if (space_info->full) {
4290 if (should_alloc_chunk(extent_root, space_info, force))
4294 spin_unlock(&space_info->lock);
4298 if (!should_alloc_chunk(extent_root, space_info, force)) {
4299 spin_unlock(&space_info->lock);
4301 } else if (space_info->chunk_alloc) {
4304 space_info->chunk_alloc = 1;
4307 spin_unlock(&space_info->lock);
4309 mutex_lock(&fs_info->chunk_mutex);
4312 * The chunk_mutex is held throughout the entirety of a chunk
4313 * allocation, so once we've acquired the chunk_mutex we know that the
4314 * other guy is done and we need to recheck and see if we should
4317 if (wait_for_alloc) {
4318 mutex_unlock(&fs_info->chunk_mutex);
4323 trans->allocating_chunk = true;
4326 * If we have mixed data/metadata chunks we want to make sure we keep
4327 * allocating mixed chunks instead of individual chunks.
4329 if (btrfs_mixed_space_info(space_info))
4330 flags |= (BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA);
4333 * if we're doing a data chunk, go ahead and make sure that
4334 * we keep a reasonable number of metadata chunks allocated in the
4337 if (flags & BTRFS_BLOCK_GROUP_DATA && fs_info->metadata_ratio) {
4338 fs_info->data_chunk_allocations++;
4339 if (!(fs_info->data_chunk_allocations %
4340 fs_info->metadata_ratio))
4341 force_metadata_allocation(fs_info);
4345 * Check if we have enough space in SYSTEM chunk because we may need
4346 * to update devices.
4348 check_system_chunk(trans, extent_root, flags);
4350 ret = btrfs_alloc_chunk(trans, extent_root, flags);
4351 trans->allocating_chunk = false;
4353 spin_lock(&space_info->lock);
4354 if (ret < 0 && ret != -ENOSPC)
4357 space_info->full = 1;
4361 space_info->force_alloc = CHUNK_ALLOC_NO_FORCE;
4363 space_info->chunk_alloc = 0;
4364 spin_unlock(&space_info->lock);
4365 mutex_unlock(&fs_info->chunk_mutex);
4367 * When we allocate a new chunk we reserve space in the chunk block
4368 * reserve to make sure we can COW nodes/leafs in the chunk tree or
4369 * add new nodes/leafs to it if we end up needing to do it when
4370 * inserting the chunk item and updating device items as part of the
4371 * second phase of chunk allocation, performed by
4372 * btrfs_finish_chunk_alloc(). So make sure we don't accumulate a
4373 * large number of new block groups to create in our transaction
4374 * handle's new_bgs list to avoid exhausting the chunk block reserve
4375 * in extreme cases - like having a single transaction create many new
4376 * block groups when starting to write out the free space caches of all
4377 * the block groups that were made dirty during the lifetime of the
4380 if (trans->can_flush_pending_bgs &&
4381 trans->chunk_bytes_reserved >= (2 * 1024 * 1024ull)) {
4382 btrfs_create_pending_block_groups(trans, trans->root);
4383 btrfs_trans_release_chunk_metadata(trans);
4388 static int can_overcommit(struct btrfs_root *root,
4389 struct btrfs_space_info *space_info, u64 bytes,
4390 enum btrfs_reserve_flush_enum flush)
4392 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
4393 u64 profile = btrfs_get_alloc_profile(root, 0);
4398 used = space_info->bytes_used + space_info->bytes_reserved +
4399 space_info->bytes_pinned + space_info->bytes_readonly;
4402 * We only want to allow over committing if we have lots of actual space
4403 * free, but if we don't have enough space to handle the global reserve
4404 * space then we could end up having a real enospc problem when trying
4405 * to allocate a chunk or some other such important allocation.
4407 spin_lock(&global_rsv->lock);
4408 space_size = calc_global_rsv_need_space(global_rsv);
4409 spin_unlock(&global_rsv->lock);
4410 if (used + space_size >= space_info->total_bytes)
4413 used += space_info->bytes_may_use;
4415 spin_lock(&root->fs_info->free_chunk_lock);
4416 avail = root->fs_info->free_chunk_space;
4417 spin_unlock(&root->fs_info->free_chunk_lock);
4420 * If we have dup, raid1 or raid10 then only half of the free
4421 * space is actually useable. For raid56, the space info used
4422 * doesn't include the parity drive, so we don't have to
4425 if (profile & (BTRFS_BLOCK_GROUP_DUP |
4426 BTRFS_BLOCK_GROUP_RAID1 |
4427 BTRFS_BLOCK_GROUP_RAID10))
4431 * If we aren't flushing all things, let us overcommit up to
4432 * 1/2th of the space. If we can flush, don't let us overcommit
4433 * too much, let it overcommit up to 1/8 of the space.
4435 if (flush == BTRFS_RESERVE_FLUSH_ALL)
4440 if (used + bytes < space_info->total_bytes + avail)
4445 static void btrfs_writeback_inodes_sb_nr(struct btrfs_root *root,
4446 unsigned long nr_pages, int nr_items)
4448 struct super_block *sb = root->fs_info->sb;
4450 if (down_read_trylock(&sb->s_umount)) {
4451 writeback_inodes_sb_nr(sb, nr_pages, WB_REASON_FS_FREE_SPACE);
4452 up_read(&sb->s_umount);
4455 * We needn't worry the filesystem going from r/w to r/o though
4456 * we don't acquire ->s_umount mutex, because the filesystem
4457 * should guarantee the delalloc inodes list be empty after
4458 * the filesystem is readonly(all dirty pages are written to
4461 btrfs_start_delalloc_roots(root->fs_info, 0, nr_items);
4462 if (!current->journal_info)
4463 btrfs_wait_ordered_roots(root->fs_info, nr_items);
4467 static inline int calc_reclaim_items_nr(struct btrfs_root *root, u64 to_reclaim)
4472 bytes = btrfs_calc_trans_metadata_size(root, 1);
4473 nr = (int)div64_u64(to_reclaim, bytes);
4479 #define EXTENT_SIZE_PER_ITEM (256 * 1024)
4482 * shrink metadata reservation for delalloc
4484 static void shrink_delalloc(struct btrfs_root *root, u64 to_reclaim, u64 orig,
4487 struct btrfs_block_rsv *block_rsv;
4488 struct btrfs_space_info *space_info;
4489 struct btrfs_trans_handle *trans;
4493 unsigned long nr_pages;
4496 enum btrfs_reserve_flush_enum flush;
4498 /* Calc the number of the pages we need flush for space reservation */
4499 items = calc_reclaim_items_nr(root, to_reclaim);
4500 to_reclaim = items * EXTENT_SIZE_PER_ITEM;
4502 trans = (struct btrfs_trans_handle *)current->journal_info;
4503 block_rsv = &root->fs_info->delalloc_block_rsv;
4504 space_info = block_rsv->space_info;
4506 delalloc_bytes = percpu_counter_sum_positive(
4507 &root->fs_info->delalloc_bytes);
4508 if (delalloc_bytes == 0) {
4512 btrfs_wait_ordered_roots(root->fs_info, items);
4517 while (delalloc_bytes && loops < 3) {
4518 max_reclaim = min(delalloc_bytes, to_reclaim);
4519 nr_pages = max_reclaim >> PAGE_CACHE_SHIFT;
4520 btrfs_writeback_inodes_sb_nr(root, nr_pages, items);
4522 * We need to wait for the async pages to actually start before
4525 max_reclaim = atomic_read(&root->fs_info->async_delalloc_pages);
4529 if (max_reclaim <= nr_pages)
4532 max_reclaim -= nr_pages;
4534 wait_event(root->fs_info->async_submit_wait,
4535 atomic_read(&root->fs_info->async_delalloc_pages) <=
4539 flush = BTRFS_RESERVE_FLUSH_ALL;
4541 flush = BTRFS_RESERVE_NO_FLUSH;
4542 spin_lock(&space_info->lock);
4543 if (can_overcommit(root, space_info, orig, flush)) {
4544 spin_unlock(&space_info->lock);
4547 spin_unlock(&space_info->lock);
4550 if (wait_ordered && !trans) {
4551 btrfs_wait_ordered_roots(root->fs_info, items);
4553 time_left = schedule_timeout_killable(1);
4557 delalloc_bytes = percpu_counter_sum_positive(
4558 &root->fs_info->delalloc_bytes);
4563 * maybe_commit_transaction - possibly commit the transaction if its ok to
4564 * @root - the root we're allocating for
4565 * @bytes - the number of bytes we want to reserve
4566 * @force - force the commit
4568 * This will check to make sure that committing the transaction will actually
4569 * get us somewhere and then commit the transaction if it does. Otherwise it
4570 * will return -ENOSPC.
4572 static int may_commit_transaction(struct btrfs_root *root,
4573 struct btrfs_space_info *space_info,
4574 u64 bytes, int force)
4576 struct btrfs_block_rsv *delayed_rsv = &root->fs_info->delayed_block_rsv;
4577 struct btrfs_trans_handle *trans;
4579 trans = (struct btrfs_trans_handle *)current->journal_info;
4586 /* See if there is enough pinned space to make this reservation */
4587 if (percpu_counter_compare(&space_info->total_bytes_pinned,
4592 * See if there is some space in the delayed insertion reservation for
4595 if (space_info != delayed_rsv->space_info)
4598 spin_lock(&delayed_rsv->lock);
4599 if (percpu_counter_compare(&space_info->total_bytes_pinned,
4600 bytes - delayed_rsv->size) >= 0) {
4601 spin_unlock(&delayed_rsv->lock);
4604 spin_unlock(&delayed_rsv->lock);
4607 trans = btrfs_join_transaction(root);
4611 return btrfs_commit_transaction(trans, root);
4615 FLUSH_DELAYED_ITEMS_NR = 1,
4616 FLUSH_DELAYED_ITEMS = 2,
4618 FLUSH_DELALLOC_WAIT = 4,
4623 static int flush_space(struct btrfs_root *root,
4624 struct btrfs_space_info *space_info, u64 num_bytes,
4625 u64 orig_bytes, int state)
4627 struct btrfs_trans_handle *trans;
4632 case FLUSH_DELAYED_ITEMS_NR:
4633 case FLUSH_DELAYED_ITEMS:
4634 if (state == FLUSH_DELAYED_ITEMS_NR)
4635 nr = calc_reclaim_items_nr(root, num_bytes) * 2;
4639 trans = btrfs_join_transaction(root);
4640 if (IS_ERR(trans)) {
4641 ret = PTR_ERR(trans);
4644 ret = btrfs_run_delayed_items_nr(trans, root, nr);
4645 btrfs_end_transaction(trans, root);
4647 case FLUSH_DELALLOC:
4648 case FLUSH_DELALLOC_WAIT:
4649 shrink_delalloc(root, num_bytes * 2, orig_bytes,
4650 state == FLUSH_DELALLOC_WAIT);
4653 trans = btrfs_join_transaction(root);
4654 if (IS_ERR(trans)) {
4655 ret = PTR_ERR(trans);
4658 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
4659 btrfs_get_alloc_profile(root, 0),
4660 CHUNK_ALLOC_NO_FORCE);
4661 btrfs_end_transaction(trans, root);
4666 ret = may_commit_transaction(root, space_info, orig_bytes, 0);
4677 btrfs_calc_reclaim_metadata_size(struct btrfs_root *root,
4678 struct btrfs_space_info *space_info)
4684 to_reclaim = min_t(u64, num_online_cpus() * 1024 * 1024,
4686 spin_lock(&space_info->lock);
4687 if (can_overcommit(root, space_info, to_reclaim,
4688 BTRFS_RESERVE_FLUSH_ALL)) {
4693 used = space_info->bytes_used + space_info->bytes_reserved +
4694 space_info->bytes_pinned + space_info->bytes_readonly +
4695 space_info->bytes_may_use;
4696 if (can_overcommit(root, space_info, 1024 * 1024,
4697 BTRFS_RESERVE_FLUSH_ALL))
4698 expected = div_factor_fine(space_info->total_bytes, 95);
4700 expected = div_factor_fine(space_info->total_bytes, 90);
4702 if (used > expected)
4703 to_reclaim = used - expected;
4706 to_reclaim = min(to_reclaim, space_info->bytes_may_use +
4707 space_info->bytes_reserved);
4709 spin_unlock(&space_info->lock);
4714 static inline int need_do_async_reclaim(struct btrfs_space_info *space_info,
4715 struct btrfs_fs_info *fs_info, u64 used)
4717 u64 thresh = div_factor_fine(space_info->total_bytes, 98);
4719 /* If we're just plain full then async reclaim just slows us down. */
4720 if (space_info->bytes_used >= thresh)
4723 return (used >= thresh && !btrfs_fs_closing(fs_info) &&
4724 !test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state));
4727 static int btrfs_need_do_async_reclaim(struct btrfs_space_info *space_info,
4728 struct btrfs_fs_info *fs_info,
4733 spin_lock(&space_info->lock);
4735 * We run out of space and have not got any free space via flush_space,
4736 * so don't bother doing async reclaim.
4738 if (flush_state > COMMIT_TRANS && space_info->full) {
4739 spin_unlock(&space_info->lock);
4743 used = space_info->bytes_used + space_info->bytes_reserved +
4744 space_info->bytes_pinned + space_info->bytes_readonly +
4745 space_info->bytes_may_use;
4746 if (need_do_async_reclaim(space_info, fs_info, used)) {
4747 spin_unlock(&space_info->lock);
4750 spin_unlock(&space_info->lock);
4755 static void btrfs_async_reclaim_metadata_space(struct work_struct *work)
4757 struct btrfs_fs_info *fs_info;
4758 struct btrfs_space_info *space_info;
4762 fs_info = container_of(work, struct btrfs_fs_info, async_reclaim_work);
4763 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
4765 to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info->fs_root,
4770 flush_state = FLUSH_DELAYED_ITEMS_NR;
4772 flush_space(fs_info->fs_root, space_info, to_reclaim,
4773 to_reclaim, flush_state);
4775 if (!btrfs_need_do_async_reclaim(space_info, fs_info,
4778 } while (flush_state < COMMIT_TRANS);
4781 void btrfs_init_async_reclaim_work(struct work_struct *work)
4783 INIT_WORK(work, btrfs_async_reclaim_metadata_space);
4787 * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
4788 * @root - the root we're allocating for
4789 * @block_rsv - the block_rsv we're allocating for
4790 * @orig_bytes - the number of bytes we want
4791 * @flush - whether or not we can flush to make our reservation
4793 * This will reserve orgi_bytes number of bytes from the space info associated
4794 * with the block_rsv. If there is not enough space it will make an attempt to
4795 * flush out space to make room. It will do this by flushing delalloc if
4796 * possible or committing the transaction. If flush is 0 then no attempts to
4797 * regain reservations will be made and this will fail if there is not enough
4800 static int reserve_metadata_bytes(struct btrfs_root *root,
4801 struct btrfs_block_rsv *block_rsv,
4803 enum btrfs_reserve_flush_enum flush)
4805 struct btrfs_space_info *space_info = block_rsv->space_info;
4807 u64 num_bytes = orig_bytes;
4808 int flush_state = FLUSH_DELAYED_ITEMS_NR;
4810 bool flushing = false;
4814 spin_lock(&space_info->lock);
4816 * We only want to wait if somebody other than us is flushing and we
4817 * are actually allowed to flush all things.
4819 while (flush == BTRFS_RESERVE_FLUSH_ALL && !flushing &&
4820 space_info->flush) {
4821 spin_unlock(&space_info->lock);
4823 * If we have a trans handle we can't wait because the flusher
4824 * may have to commit the transaction, which would mean we would
4825 * deadlock since we are waiting for the flusher to finish, but
4826 * hold the current transaction open.
4828 if (current->journal_info)
4830 ret = wait_event_killable(space_info->wait, !space_info->flush);
4831 /* Must have been killed, return */
4835 spin_lock(&space_info->lock);
4839 used = space_info->bytes_used + space_info->bytes_reserved +
4840 space_info->bytes_pinned + space_info->bytes_readonly +
4841 space_info->bytes_may_use;
4844 * The idea here is that we've not already over-reserved the block group
4845 * then we can go ahead and save our reservation first and then start
4846 * flushing if we need to. Otherwise if we've already overcommitted
4847 * lets start flushing stuff first and then come back and try to make
4850 if (used <= space_info->total_bytes) {
4851 if (used + orig_bytes <= space_info->total_bytes) {
4852 space_info->bytes_may_use += orig_bytes;
4853 trace_btrfs_space_reservation(root->fs_info,
4854 "space_info", space_info->flags, orig_bytes, 1);
4858 * Ok set num_bytes to orig_bytes since we aren't
4859 * overocmmitted, this way we only try and reclaim what
4862 num_bytes = orig_bytes;
4866 * Ok we're over committed, set num_bytes to the overcommitted
4867 * amount plus the amount of bytes that we need for this
4870 num_bytes = used - space_info->total_bytes +
4874 if (ret && can_overcommit(root, space_info, orig_bytes, flush)) {
4875 space_info->bytes_may_use += orig_bytes;
4876 trace_btrfs_space_reservation(root->fs_info, "space_info",
4877 space_info->flags, orig_bytes,
4883 * Couldn't make our reservation, save our place so while we're trying
4884 * to reclaim space we can actually use it instead of somebody else
4885 * stealing it from us.
4887 * We make the other tasks wait for the flush only when we can flush
4890 if (ret && flush != BTRFS_RESERVE_NO_FLUSH) {
4892 space_info->flush = 1;
4893 } else if (!ret && space_info->flags & BTRFS_BLOCK_GROUP_METADATA) {
4896 * We will do the space reservation dance during log replay,
4897 * which means we won't have fs_info->fs_root set, so don't do
4898 * the async reclaim as we will panic.
4900 if (!root->fs_info->log_root_recovering &&
4901 need_do_async_reclaim(space_info, root->fs_info, used) &&
4902 !work_busy(&root->fs_info->async_reclaim_work))
4903 queue_work(system_unbound_wq,
4904 &root->fs_info->async_reclaim_work);
4906 spin_unlock(&space_info->lock);
4908 if (!ret || flush == BTRFS_RESERVE_NO_FLUSH)
4911 ret = flush_space(root, space_info, num_bytes, orig_bytes,
4916 * If we are FLUSH_LIMIT, we can not flush delalloc, or the deadlock
4917 * would happen. So skip delalloc flush.
4919 if (flush == BTRFS_RESERVE_FLUSH_LIMIT &&
4920 (flush_state == FLUSH_DELALLOC ||
4921 flush_state == FLUSH_DELALLOC_WAIT))
4922 flush_state = ALLOC_CHUNK;
4926 else if (flush == BTRFS_RESERVE_FLUSH_LIMIT &&
4927 flush_state < COMMIT_TRANS)
4929 else if (flush == BTRFS_RESERVE_FLUSH_ALL &&
4930 flush_state <= COMMIT_TRANS)
4934 if (ret == -ENOSPC &&
4935 unlikely(root->orphan_cleanup_state == ORPHAN_CLEANUP_STARTED)) {
4936 struct btrfs_block_rsv *global_rsv =
4937 &root->fs_info->global_block_rsv;
4939 if (block_rsv != global_rsv &&
4940 !block_rsv_use_bytes(global_rsv, orig_bytes))
4944 trace_btrfs_space_reservation(root->fs_info,
4945 "space_info:enospc",
4946 space_info->flags, orig_bytes, 1);
4948 spin_lock(&space_info->lock);
4949 space_info->flush = 0;
4950 wake_up_all(&space_info->wait);
4951 spin_unlock(&space_info->lock);
4956 static struct btrfs_block_rsv *get_block_rsv(
4957 const struct btrfs_trans_handle *trans,
4958 const struct btrfs_root *root)
4960 struct btrfs_block_rsv *block_rsv = NULL;
4962 if (test_bit(BTRFS_ROOT_REF_COWS, &root->state) ||
4963 (root == root->fs_info->csum_root && trans->adding_csums) ||
4964 (root == root->fs_info->uuid_root))
4965 block_rsv = trans->block_rsv;
4968 block_rsv = root->block_rsv;
4971 block_rsv = &root->fs_info->empty_block_rsv;
4976 static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
4980 spin_lock(&block_rsv->lock);
4981 if (block_rsv->reserved >= num_bytes) {
4982 block_rsv->reserved -= num_bytes;
4983 if (block_rsv->reserved < block_rsv->size)
4984 block_rsv->full = 0;
4987 spin_unlock(&block_rsv->lock);
4991 static void block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
4992 u64 num_bytes, int update_size)
4994 spin_lock(&block_rsv->lock);
4995 block_rsv->reserved += num_bytes;
4997 block_rsv->size += num_bytes;
4998 else if (block_rsv->reserved >= block_rsv->size)
4999 block_rsv->full = 1;
5000 spin_unlock(&block_rsv->lock);
5003 int btrfs_cond_migrate_bytes(struct btrfs_fs_info *fs_info,
5004 struct btrfs_block_rsv *dest, u64 num_bytes,
5007 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
5010 if (global_rsv->space_info != dest->space_info)
5013 spin_lock(&global_rsv->lock);
5014 min_bytes = div_factor(global_rsv->size, min_factor);
5015 if (global_rsv->reserved < min_bytes + num_bytes) {
5016 spin_unlock(&global_rsv->lock);
5019 global_rsv->reserved -= num_bytes;
5020 if (global_rsv->reserved < global_rsv->size)
5021 global_rsv->full = 0;
5022 spin_unlock(&global_rsv->lock);
5024 block_rsv_add_bytes(dest, num_bytes, 1);
5028 static void block_rsv_release_bytes(struct btrfs_fs_info *fs_info,
5029 struct btrfs_block_rsv *block_rsv,
5030 struct btrfs_block_rsv *dest, u64 num_bytes)
5032 struct btrfs_space_info *space_info = block_rsv->space_info;
5034 spin_lock(&block_rsv->lock);
5035 if (num_bytes == (u64)-1)
5036 num_bytes = block_rsv->size;
5037 block_rsv->size -= num_bytes;
5038 if (block_rsv->reserved >= block_rsv->size) {
5039 num_bytes = block_rsv->reserved - block_rsv->size;
5040 block_rsv->reserved = block_rsv->size;
5041 block_rsv->full = 1;
5045 spin_unlock(&block_rsv->lock);
5047 if (num_bytes > 0) {
5049 spin_lock(&dest->lock);
5053 bytes_to_add = dest->size - dest->reserved;
5054 bytes_to_add = min(num_bytes, bytes_to_add);
5055 dest->reserved += bytes_to_add;
5056 if (dest->reserved >= dest->size)
5058 num_bytes -= bytes_to_add;
5060 spin_unlock(&dest->lock);
5063 spin_lock(&space_info->lock);
5064 space_info->bytes_may_use -= num_bytes;
5065 trace_btrfs_space_reservation(fs_info, "space_info",
5066 space_info->flags, num_bytes, 0);
5067 spin_unlock(&space_info->lock);
5072 static int block_rsv_migrate_bytes(struct btrfs_block_rsv *src,
5073 struct btrfs_block_rsv *dst, u64 num_bytes)
5077 ret = block_rsv_use_bytes(src, num_bytes);
5081 block_rsv_add_bytes(dst, num_bytes, 1);
5085 void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv, unsigned short type)
5087 memset(rsv, 0, sizeof(*rsv));
5088 spin_lock_init(&rsv->lock);
5092 struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_root *root,
5093 unsigned short type)
5095 struct btrfs_block_rsv *block_rsv;
5096 struct btrfs_fs_info *fs_info = root->fs_info;
5098 block_rsv = kmalloc(sizeof(*block_rsv), GFP_NOFS);
5102 btrfs_init_block_rsv(block_rsv, type);
5103 block_rsv->space_info = __find_space_info(fs_info,
5104 BTRFS_BLOCK_GROUP_METADATA);
5108 void btrfs_free_block_rsv(struct btrfs_root *root,
5109 struct btrfs_block_rsv *rsv)
5113 btrfs_block_rsv_release(root, rsv, (u64)-1);
5117 void __btrfs_free_block_rsv(struct btrfs_block_rsv *rsv)
5122 int btrfs_block_rsv_add(struct btrfs_root *root,
5123 struct btrfs_block_rsv *block_rsv, u64 num_bytes,
5124 enum btrfs_reserve_flush_enum flush)
5131 ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
5133 block_rsv_add_bytes(block_rsv, num_bytes, 1);
5140 int btrfs_block_rsv_check(struct btrfs_root *root,
5141 struct btrfs_block_rsv *block_rsv, int min_factor)
5149 spin_lock(&block_rsv->lock);
5150 num_bytes = div_factor(block_rsv->size, min_factor);
5151 if (block_rsv->reserved >= num_bytes)
5153 spin_unlock(&block_rsv->lock);
5158 int btrfs_block_rsv_refill(struct btrfs_root *root,
5159 struct btrfs_block_rsv *block_rsv, u64 min_reserved,
5160 enum btrfs_reserve_flush_enum flush)
5168 spin_lock(&block_rsv->lock);
5169 num_bytes = min_reserved;
5170 if (block_rsv->reserved >= num_bytes)
5173 num_bytes -= block_rsv->reserved;
5174 spin_unlock(&block_rsv->lock);
5179 ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
5181 block_rsv_add_bytes(block_rsv, num_bytes, 0);
5188 int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,
5189 struct btrfs_block_rsv *dst_rsv,
5192 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
5195 void btrfs_block_rsv_release(struct btrfs_root *root,
5196 struct btrfs_block_rsv *block_rsv,
5199 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
5200 if (global_rsv == block_rsv ||
5201 block_rsv->space_info != global_rsv->space_info)
5203 block_rsv_release_bytes(root->fs_info, block_rsv, global_rsv,
5208 * helper to calculate size of global block reservation.
5209 * the desired value is sum of space used by extent tree,
5210 * checksum tree and root tree
5212 static u64 calc_global_metadata_size(struct btrfs_fs_info *fs_info)
5214 struct btrfs_space_info *sinfo;
5218 int csum_size = btrfs_super_csum_size(fs_info->super_copy);
5220 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_DATA);
5221 spin_lock(&sinfo->lock);
5222 data_used = sinfo->bytes_used;
5223 spin_unlock(&sinfo->lock);
5225 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
5226 spin_lock(&sinfo->lock);
5227 if (sinfo->flags & BTRFS_BLOCK_GROUP_DATA)
5229 meta_used = sinfo->bytes_used;
5230 spin_unlock(&sinfo->lock);
5232 num_bytes = (data_used >> fs_info->sb->s_blocksize_bits) *
5234 num_bytes += div_u64(data_used + meta_used, 50);
5236 if (num_bytes * 3 > meta_used)
5237 num_bytes = div_u64(meta_used, 3);
5239 return ALIGN(num_bytes, fs_info->extent_root->nodesize << 10);
5242 static void update_global_block_rsv(struct btrfs_fs_info *fs_info)
5244 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
5245 struct btrfs_space_info *sinfo = block_rsv->space_info;
5248 num_bytes = calc_global_metadata_size(fs_info);
5250 spin_lock(&sinfo->lock);
5251 spin_lock(&block_rsv->lock);
5253 block_rsv->size = min_t(u64, num_bytes, 512 * 1024 * 1024);
5255 num_bytes = sinfo->bytes_used + sinfo->bytes_pinned +
5256 sinfo->bytes_reserved + sinfo->bytes_readonly +
5257 sinfo->bytes_may_use;
5259 if (sinfo->total_bytes > num_bytes) {
5260 num_bytes = sinfo->total_bytes - num_bytes;
5261 block_rsv->reserved += num_bytes;
5262 sinfo->bytes_may_use += num_bytes;
5263 trace_btrfs_space_reservation(fs_info, "space_info",
5264 sinfo->flags, num_bytes, 1);
5267 if (block_rsv->reserved >= block_rsv->size) {
5268 num_bytes = block_rsv->reserved - block_rsv->size;
5269 sinfo->bytes_may_use -= num_bytes;
5270 trace_btrfs_space_reservation(fs_info, "space_info",
5271 sinfo->flags, num_bytes, 0);
5272 block_rsv->reserved = block_rsv->size;
5273 block_rsv->full = 1;
5276 spin_unlock(&block_rsv->lock);
5277 spin_unlock(&sinfo->lock);
5280 static void init_global_block_rsv(struct btrfs_fs_info *fs_info)
5282 struct btrfs_space_info *space_info;
5284 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
5285 fs_info->chunk_block_rsv.space_info = space_info;
5287 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
5288 fs_info->global_block_rsv.space_info = space_info;
5289 fs_info->delalloc_block_rsv.space_info = space_info;
5290 fs_info->trans_block_rsv.space_info = space_info;
5291 fs_info->empty_block_rsv.space_info = space_info;
5292 fs_info->delayed_block_rsv.space_info = space_info;
5294 fs_info->extent_root->block_rsv = &fs_info->global_block_rsv;
5295 fs_info->csum_root->block_rsv = &fs_info->global_block_rsv;
5296 fs_info->dev_root->block_rsv = &fs_info->global_block_rsv;
5297 fs_info->tree_root->block_rsv = &fs_info->global_block_rsv;
5298 if (fs_info->quota_root)
5299 fs_info->quota_root->block_rsv = &fs_info->global_block_rsv;
5300 fs_info->chunk_root->block_rsv = &fs_info->chunk_block_rsv;
5302 update_global_block_rsv(fs_info);
5305 static void release_global_block_rsv(struct btrfs_fs_info *fs_info)
5307 block_rsv_release_bytes(fs_info, &fs_info->global_block_rsv, NULL,
5309 WARN_ON(fs_info->delalloc_block_rsv.size > 0);
5310 WARN_ON(fs_info->delalloc_block_rsv.reserved > 0);
5311 WARN_ON(fs_info->trans_block_rsv.size > 0);
5312 WARN_ON(fs_info->trans_block_rsv.reserved > 0);
5313 WARN_ON(fs_info->chunk_block_rsv.size > 0);
5314 WARN_ON(fs_info->chunk_block_rsv.reserved > 0);
5315 WARN_ON(fs_info->delayed_block_rsv.size > 0);
5316 WARN_ON(fs_info->delayed_block_rsv.reserved > 0);
5319 void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans,
5320 struct btrfs_root *root)
5322 if (!trans->block_rsv)
5325 if (!trans->bytes_reserved)
5328 trace_btrfs_space_reservation(root->fs_info, "transaction",
5329 trans->transid, trans->bytes_reserved, 0);
5330 btrfs_block_rsv_release(root, trans->block_rsv, trans->bytes_reserved);
5331 trans->bytes_reserved = 0;
5335 * To be called after all the new block groups attached to the transaction
5336 * handle have been created (btrfs_create_pending_block_groups()).
5338 void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans)
5340 struct btrfs_fs_info *fs_info = trans->root->fs_info;
5342 if (!trans->chunk_bytes_reserved)
5345 WARN_ON_ONCE(!list_empty(&trans->new_bgs));
5347 block_rsv_release_bytes(fs_info, &fs_info->chunk_block_rsv, NULL,
5348 trans->chunk_bytes_reserved);
5349 trans->chunk_bytes_reserved = 0;
5352 /* Can only return 0 or -ENOSPC */
5353 int btrfs_orphan_reserve_metadata(struct btrfs_trans_handle *trans,
5354 struct inode *inode)
5356 struct btrfs_root *root = BTRFS_I(inode)->root;
5357 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
5358 struct btrfs_block_rsv *dst_rsv = root->orphan_block_rsv;
5361 * We need to hold space in order to delete our orphan item once we've
5362 * added it, so this takes the reservation so we can release it later
5363 * when we are truly done with the orphan item.
5365 u64 num_bytes = btrfs_calc_trans_metadata_size(root, 1);
5366 trace_btrfs_space_reservation(root->fs_info, "orphan",
5367 btrfs_ino(inode), num_bytes, 1);
5368 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
5371 void btrfs_orphan_release_metadata(struct inode *inode)
5373 struct btrfs_root *root = BTRFS_I(inode)->root;
5374 u64 num_bytes = btrfs_calc_trans_metadata_size(root, 1);
5375 trace_btrfs_space_reservation(root->fs_info, "orphan",
5376 btrfs_ino(inode), num_bytes, 0);
5377 btrfs_block_rsv_release(root, root->orphan_block_rsv, num_bytes);
5381 * btrfs_subvolume_reserve_metadata() - reserve space for subvolume operation
5382 * root: the root of the parent directory
5383 * rsv: block reservation
5384 * items: the number of items that we need do reservation
5385 * qgroup_reserved: used to return the reserved size in qgroup
5387 * This function is used to reserve the space for snapshot/subvolume
5388 * creation and deletion. Those operations are different with the
5389 * common file/directory operations, they change two fs/file trees
5390 * and root tree, the number of items that the qgroup reserves is
5391 * different with the free space reservation. So we can not use
5392 * the space reseravtion mechanism in start_transaction().
5394 int btrfs_subvolume_reserve_metadata(struct btrfs_root *root,
5395 struct btrfs_block_rsv *rsv,
5397 u64 *qgroup_reserved,
5398 bool use_global_rsv)
5402 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
5404 if (root->fs_info->quota_enabled) {
5405 /* One for parent inode, two for dir entries */
5406 num_bytes = 3 * root->nodesize;
5407 ret = btrfs_qgroup_reserve_meta(root, num_bytes);
5414 *qgroup_reserved = num_bytes;
5416 num_bytes = btrfs_calc_trans_metadata_size(root, items);
5417 rsv->space_info = __find_space_info(root->fs_info,
5418 BTRFS_BLOCK_GROUP_METADATA);
5419 ret = btrfs_block_rsv_add(root, rsv, num_bytes,
5420 BTRFS_RESERVE_FLUSH_ALL);
5422 if (ret == -ENOSPC && use_global_rsv)
5423 ret = btrfs_block_rsv_migrate(global_rsv, rsv, num_bytes);
5425 if (ret && *qgroup_reserved)
5426 btrfs_qgroup_free_meta(root, *qgroup_reserved);
5431 void btrfs_subvolume_release_metadata(struct btrfs_root *root,
5432 struct btrfs_block_rsv *rsv,
5433 u64 qgroup_reserved)
5435 btrfs_block_rsv_release(root, rsv, (u64)-1);
5439 * drop_outstanding_extent - drop an outstanding extent
5440 * @inode: the inode we're dropping the extent for
5441 * @num_bytes: the number of bytes we're relaseing.
5443 * This is called when we are freeing up an outstanding extent, either called
5444 * after an error or after an extent is written. This will return the number of
5445 * reserved extents that need to be freed. This must be called with
5446 * BTRFS_I(inode)->lock held.
5448 static unsigned drop_outstanding_extent(struct inode *inode, u64 num_bytes)
5450 unsigned drop_inode_space = 0;
5451 unsigned dropped_extents = 0;
5452 unsigned num_extents = 0;
5454 num_extents = (unsigned)div64_u64(num_bytes +
5455 BTRFS_MAX_EXTENT_SIZE - 1,
5456 BTRFS_MAX_EXTENT_SIZE);
5457 ASSERT(num_extents);
5458 ASSERT(BTRFS_I(inode)->outstanding_extents >= num_extents);
5459 BTRFS_I(inode)->outstanding_extents -= num_extents;
5461 if (BTRFS_I(inode)->outstanding_extents == 0 &&
5462 test_and_clear_bit(BTRFS_INODE_DELALLOC_META_RESERVED,
5463 &BTRFS_I(inode)->runtime_flags))
5464 drop_inode_space = 1;
5467 * If we have more or the same amount of outsanding extents than we have
5468 * reserved then we need to leave the reserved extents count alone.
5470 if (BTRFS_I(inode)->outstanding_extents >=
5471 BTRFS_I(inode)->reserved_extents)
5472 return drop_inode_space;
5474 dropped_extents = BTRFS_I(inode)->reserved_extents -
5475 BTRFS_I(inode)->outstanding_extents;
5476 BTRFS_I(inode)->reserved_extents -= dropped_extents;
5477 return dropped_extents + drop_inode_space;
5481 * calc_csum_metadata_size - return the amount of metada space that must be
5482 * reserved/free'd for the given bytes.
5483 * @inode: the inode we're manipulating
5484 * @num_bytes: the number of bytes in question
5485 * @reserve: 1 if we are reserving space, 0 if we are freeing space
5487 * This adjusts the number of csum_bytes in the inode and then returns the
5488 * correct amount of metadata that must either be reserved or freed. We
5489 * calculate how many checksums we can fit into one leaf and then divide the
5490 * number of bytes that will need to be checksumed by this value to figure out
5491 * how many checksums will be required. If we are adding bytes then the number
5492 * may go up and we will return the number of additional bytes that must be
5493 * reserved. If it is going down we will return the number of bytes that must
5496 * This must be called with BTRFS_I(inode)->lock held.
5498 static u64 calc_csum_metadata_size(struct inode *inode, u64 num_bytes,
5501 struct btrfs_root *root = BTRFS_I(inode)->root;
5502 u64 old_csums, num_csums;
5504 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM &&
5505 BTRFS_I(inode)->csum_bytes == 0)
5508 old_csums = btrfs_csum_bytes_to_leaves(root, BTRFS_I(inode)->csum_bytes);
5510 BTRFS_I(inode)->csum_bytes += num_bytes;
5512 BTRFS_I(inode)->csum_bytes -= num_bytes;
5513 num_csums = btrfs_csum_bytes_to_leaves(root, BTRFS_I(inode)->csum_bytes);
5515 /* No change, no need to reserve more */
5516 if (old_csums == num_csums)
5520 return btrfs_calc_trans_metadata_size(root,
5521 num_csums - old_csums);
5523 return btrfs_calc_trans_metadata_size(root, old_csums - num_csums);
5526 int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
5528 struct btrfs_root *root = BTRFS_I(inode)->root;
5529 struct btrfs_block_rsv *block_rsv = &root->fs_info->delalloc_block_rsv;
5532 unsigned nr_extents = 0;
5533 int extra_reserve = 0;
5534 enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_FLUSH_ALL;
5536 bool delalloc_lock = true;
5540 /* If we are a free space inode we need to not flush since we will be in
5541 * the middle of a transaction commit. We also don't need the delalloc
5542 * mutex since we won't race with anybody. We need this mostly to make
5543 * lockdep shut its filthy mouth.
5545 if (btrfs_is_free_space_inode(inode)) {
5546 flush = BTRFS_RESERVE_NO_FLUSH;
5547 delalloc_lock = false;
5550 if (flush != BTRFS_RESERVE_NO_FLUSH &&
5551 btrfs_transaction_in_commit(root->fs_info))
5552 schedule_timeout(1);
5555 mutex_lock(&BTRFS_I(inode)->delalloc_mutex);
5557 num_bytes = ALIGN(num_bytes, root->sectorsize);
5559 spin_lock(&BTRFS_I(inode)->lock);
5560 nr_extents = (unsigned)div64_u64(num_bytes +
5561 BTRFS_MAX_EXTENT_SIZE - 1,
5562 BTRFS_MAX_EXTENT_SIZE);
5563 BTRFS_I(inode)->outstanding_extents += nr_extents;
5566 if (BTRFS_I(inode)->outstanding_extents >
5567 BTRFS_I(inode)->reserved_extents)
5568 nr_extents = BTRFS_I(inode)->outstanding_extents -
5569 BTRFS_I(inode)->reserved_extents;
5572 * Add an item to reserve for updating the inode when we complete the
5575 if (!test_bit(BTRFS_INODE_DELALLOC_META_RESERVED,
5576 &BTRFS_I(inode)->runtime_flags)) {
5581 to_reserve = btrfs_calc_trans_metadata_size(root, nr_extents);
5582 to_reserve += calc_csum_metadata_size(inode, num_bytes, 1);
5583 csum_bytes = BTRFS_I(inode)->csum_bytes;
5584 spin_unlock(&BTRFS_I(inode)->lock);
5586 if (root->fs_info->quota_enabled) {
5587 ret = btrfs_qgroup_reserve_meta(root,
5588 nr_extents * root->nodesize);
5593 ret = reserve_metadata_bytes(root, block_rsv, to_reserve, flush);
5594 if (unlikely(ret)) {
5595 btrfs_qgroup_free_meta(root, nr_extents * root->nodesize);
5599 spin_lock(&BTRFS_I(inode)->lock);
5600 if (extra_reserve) {
5601 set_bit(BTRFS_INODE_DELALLOC_META_RESERVED,
5602 &BTRFS_I(inode)->runtime_flags);
5605 BTRFS_I(inode)->reserved_extents += nr_extents;
5606 spin_unlock(&BTRFS_I(inode)->lock);
5609 mutex_unlock(&BTRFS_I(inode)->delalloc_mutex);
5612 trace_btrfs_space_reservation(root->fs_info, "delalloc",
5613 btrfs_ino(inode), to_reserve, 1);
5614 block_rsv_add_bytes(block_rsv, to_reserve, 1);
5619 spin_lock(&BTRFS_I(inode)->lock);
5620 dropped = drop_outstanding_extent(inode, num_bytes);
5622 * If the inodes csum_bytes is the same as the original
5623 * csum_bytes then we know we haven't raced with any free()ers
5624 * so we can just reduce our inodes csum bytes and carry on.
5626 if (BTRFS_I(inode)->csum_bytes == csum_bytes) {
5627 calc_csum_metadata_size(inode, num_bytes, 0);
5629 u64 orig_csum_bytes = BTRFS_I(inode)->csum_bytes;
5633 * This is tricky, but first we need to figure out how much we
5634 * free'd from any free-ers that occured during this
5635 * reservation, so we reset ->csum_bytes to the csum_bytes
5636 * before we dropped our lock, and then call the free for the
5637 * number of bytes that were freed while we were trying our
5640 bytes = csum_bytes - BTRFS_I(inode)->csum_bytes;
5641 BTRFS_I(inode)->csum_bytes = csum_bytes;
5642 to_free = calc_csum_metadata_size(inode, bytes, 0);
5646 * Now we need to see how much we would have freed had we not
5647 * been making this reservation and our ->csum_bytes were not
5648 * artificially inflated.
5650 BTRFS_I(inode)->csum_bytes = csum_bytes - num_bytes;
5651 bytes = csum_bytes - orig_csum_bytes;
5652 bytes = calc_csum_metadata_size(inode, bytes, 0);
5655 * Now reset ->csum_bytes to what it should be. If bytes is
5656 * more than to_free then we would have free'd more space had we
5657 * not had an artificially high ->csum_bytes, so we need to free
5658 * the remainder. If bytes is the same or less then we don't
5659 * need to do anything, the other free-ers did the correct
5662 BTRFS_I(inode)->csum_bytes = orig_csum_bytes - num_bytes;
5663 if (bytes > to_free)
5664 to_free = bytes - to_free;
5668 spin_unlock(&BTRFS_I(inode)->lock);
5670 to_free += btrfs_calc_trans_metadata_size(root, dropped);
5673 btrfs_block_rsv_release(root, block_rsv, to_free);
5674 trace_btrfs_space_reservation(root->fs_info, "delalloc",
5675 btrfs_ino(inode), to_free, 0);
5678 mutex_unlock(&BTRFS_I(inode)->delalloc_mutex);
5683 * btrfs_delalloc_release_metadata - release a metadata reservation for an inode
5684 * @inode: the inode to release the reservation for
5685 * @num_bytes: the number of bytes we're releasing
5687 * This will release the metadata reservation for an inode. This can be called
5688 * once we complete IO for a given set of bytes to release their metadata
5691 void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes)
5693 struct btrfs_root *root = BTRFS_I(inode)->root;
5697 num_bytes = ALIGN(num_bytes, root->sectorsize);
5698 spin_lock(&BTRFS_I(inode)->lock);
5699 dropped = drop_outstanding_extent(inode, num_bytes);
5702 to_free = calc_csum_metadata_size(inode, num_bytes, 0);
5703 spin_unlock(&BTRFS_I(inode)->lock);
5705 to_free += btrfs_calc_trans_metadata_size(root, dropped);
5707 if (btrfs_test_is_dummy_root(root))
5710 trace_btrfs_space_reservation(root->fs_info, "delalloc",
5711 btrfs_ino(inode), to_free, 0);
5713 btrfs_block_rsv_release(root, &root->fs_info->delalloc_block_rsv,
5718 * btrfs_delalloc_reserve_space - reserve data and metadata space for delalloc
5719 * @inode: inode we're writing to
5720 * @num_bytes: the number of bytes we want to allocate
5722 * This will do the following things
5724 * o reserve space in the data space info for num_bytes
5725 * o reserve space in the metadata space info based on number of outstanding
5726 * extents and how much csums will be needed
5727 * o add to the inodes ->delalloc_bytes
5728 * o add it to the fs_info's delalloc inodes list.
5730 * This will return 0 for success and -ENOSPC if there is no space left.
5732 int btrfs_delalloc_reserve_space(struct inode *inode, u64 num_bytes)
5736 ret = btrfs_check_data_free_space(inode, num_bytes, num_bytes);
5740 ret = btrfs_delalloc_reserve_metadata(inode, num_bytes);
5742 btrfs_free_reserved_data_space(inode, num_bytes);
5750 * btrfs_delalloc_release_space - release data and metadata space for delalloc
5751 * @inode: inode we're releasing space for
5752 * @num_bytes: the number of bytes we want to free up
5754 * This must be matched with a call to btrfs_delalloc_reserve_space. This is
5755 * called in the case that we don't need the metadata AND data reservations
5756 * anymore. So if there is an error or we insert an inline extent.
5758 * This function will release the metadata space that was not used and will
5759 * decrement ->delalloc_bytes and remove it from the fs_info delalloc_inodes
5760 * list if there are no delalloc bytes left.
5762 void btrfs_delalloc_release_space(struct inode *inode, u64 num_bytes)
5764 btrfs_delalloc_release_metadata(inode, num_bytes);
5765 btrfs_free_reserved_data_space(inode, num_bytes);
5768 static int update_block_group(struct btrfs_trans_handle *trans,
5769 struct btrfs_root *root, u64 bytenr,
5770 u64 num_bytes, int alloc)
5772 struct btrfs_block_group_cache *cache = NULL;
5773 struct btrfs_fs_info *info = root->fs_info;
5774 u64 total = num_bytes;
5779 /* block accounting for super block */
5780 spin_lock(&info->delalloc_root_lock);
5781 old_val = btrfs_super_bytes_used(info->super_copy);
5783 old_val += num_bytes;
5785 old_val -= num_bytes;
5786 btrfs_set_super_bytes_used(info->super_copy, old_val);
5787 spin_unlock(&info->delalloc_root_lock);
5790 cache = btrfs_lookup_block_group(info, bytenr);
5793 if (cache->flags & (BTRFS_BLOCK_GROUP_DUP |
5794 BTRFS_BLOCK_GROUP_RAID1 |
5795 BTRFS_BLOCK_GROUP_RAID10))
5800 * If this block group has free space cache written out, we
5801 * need to make sure to load it if we are removing space. This
5802 * is because we need the unpinning stage to actually add the
5803 * space back to the block group, otherwise we will leak space.
5805 if (!alloc && cache->cached == BTRFS_CACHE_NO)
5806 cache_block_group(cache, 1);
5808 byte_in_group = bytenr - cache->key.objectid;
5809 WARN_ON(byte_in_group > cache->key.offset);
5811 spin_lock(&cache->space_info->lock);
5812 spin_lock(&cache->lock);
5814 if (btrfs_test_opt(root, SPACE_CACHE) &&
5815 cache->disk_cache_state < BTRFS_DC_CLEAR)
5816 cache->disk_cache_state = BTRFS_DC_CLEAR;
5818 old_val = btrfs_block_group_used(&cache->item);
5819 num_bytes = min(total, cache->key.offset - byte_in_group);
5821 old_val += num_bytes;
5822 btrfs_set_block_group_used(&cache->item, old_val);
5823 cache->reserved -= num_bytes;
5824 cache->space_info->bytes_reserved -= num_bytes;
5825 cache->space_info->bytes_used += num_bytes;
5826 cache->space_info->disk_used += num_bytes * factor;
5827 spin_unlock(&cache->lock);
5828 spin_unlock(&cache->space_info->lock);
5830 old_val -= num_bytes;
5831 btrfs_set_block_group_used(&cache->item, old_val);
5832 cache->pinned += num_bytes;
5833 cache->space_info->bytes_pinned += num_bytes;
5834 cache->space_info->bytes_used -= num_bytes;
5835 cache->space_info->disk_used -= num_bytes * factor;
5836 spin_unlock(&cache->lock);
5837 spin_unlock(&cache->space_info->lock);
5839 set_extent_dirty(info->pinned_extents,
5840 bytenr, bytenr + num_bytes - 1,
5841 GFP_NOFS | __GFP_NOFAIL);
5843 * No longer have used bytes in this block group, queue
5847 spin_lock(&info->unused_bgs_lock);
5848 if (list_empty(&cache->bg_list)) {
5849 btrfs_get_block_group(cache);
5850 list_add_tail(&cache->bg_list,
5853 spin_unlock(&info->unused_bgs_lock);
5857 spin_lock(&trans->transaction->dirty_bgs_lock);
5858 if (list_empty(&cache->dirty_list)) {
5859 list_add_tail(&cache->dirty_list,
5860 &trans->transaction->dirty_bgs);
5861 trans->transaction->num_dirty_bgs++;
5862 btrfs_get_block_group(cache);
5864 spin_unlock(&trans->transaction->dirty_bgs_lock);
5866 btrfs_put_block_group(cache);
5868 bytenr += num_bytes;
5873 static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
5875 struct btrfs_block_group_cache *cache;
5878 spin_lock(&root->fs_info->block_group_cache_lock);
5879 bytenr = root->fs_info->first_logical_byte;
5880 spin_unlock(&root->fs_info->block_group_cache_lock);
5882 if (bytenr < (u64)-1)
5885 cache = btrfs_lookup_first_block_group(root->fs_info, search_start);
5889 bytenr = cache->key.objectid;
5890 btrfs_put_block_group(cache);
5895 static int pin_down_extent(struct btrfs_root *root,
5896 struct btrfs_block_group_cache *cache,
5897 u64 bytenr, u64 num_bytes, int reserved)
5899 spin_lock(&cache->space_info->lock);
5900 spin_lock(&cache->lock);
5901 cache->pinned += num_bytes;
5902 cache->space_info->bytes_pinned += num_bytes;
5904 cache->reserved -= num_bytes;
5905 cache->space_info->bytes_reserved -= num_bytes;
5907 spin_unlock(&cache->lock);
5908 spin_unlock(&cache->space_info->lock);
5910 set_extent_dirty(root->fs_info->pinned_extents, bytenr,
5911 bytenr + num_bytes - 1, GFP_NOFS | __GFP_NOFAIL);
5913 trace_btrfs_reserved_extent_free(root, bytenr, num_bytes);
5918 * this function must be called within transaction
5920 int btrfs_pin_extent(struct btrfs_root *root,
5921 u64 bytenr, u64 num_bytes, int reserved)
5923 struct btrfs_block_group_cache *cache;
5925 cache = btrfs_lookup_block_group(root->fs_info, bytenr);
5926 BUG_ON(!cache); /* Logic error */
5928 pin_down_extent(root, cache, bytenr, num_bytes, reserved);
5930 btrfs_put_block_group(cache);
5935 * this function must be called within transaction
5937 int btrfs_pin_extent_for_log_replay(struct btrfs_root *root,
5938 u64 bytenr, u64 num_bytes)
5940 struct btrfs_block_group_cache *cache;
5943 cache = btrfs_lookup_block_group(root->fs_info, bytenr);
5948 * pull in the free space cache (if any) so that our pin
5949 * removes the free space from the cache. We have load_only set
5950 * to one because the slow code to read in the free extents does check
5951 * the pinned extents.
5953 cache_block_group(cache, 1);
5955 pin_down_extent(root, cache, bytenr, num_bytes, 0);
5957 /* remove us from the free space cache (if we're there at all) */
5958 ret = btrfs_remove_free_space(cache, bytenr, num_bytes);
5959 btrfs_put_block_group(cache);
5963 static int __exclude_logged_extent(struct btrfs_root *root, u64 start, u64 num_bytes)
5966 struct btrfs_block_group_cache *block_group;
5967 struct btrfs_caching_control *caching_ctl;
5969 block_group = btrfs_lookup_block_group(root->fs_info, start);
5973 cache_block_group(block_group, 0);
5974 caching_ctl = get_caching_control(block_group);
5978 BUG_ON(!block_group_cache_done(block_group));
5979 ret = btrfs_remove_free_space(block_group, start, num_bytes);
5981 mutex_lock(&caching_ctl->mutex);
5983 if (start >= caching_ctl->progress) {
5984 ret = add_excluded_extent(root, start, num_bytes);
5985 } else if (start + num_bytes <= caching_ctl->progress) {
5986 ret = btrfs_remove_free_space(block_group,
5989 num_bytes = caching_ctl->progress - start;
5990 ret = btrfs_remove_free_space(block_group,
5995 num_bytes = (start + num_bytes) -
5996 caching_ctl->progress;
5997 start = caching_ctl->progress;
5998 ret = add_excluded_extent(root, start, num_bytes);
6001 mutex_unlock(&caching_ctl->mutex);
6002 put_caching_control(caching_ctl);
6004 btrfs_put_block_group(block_group);
6008 int btrfs_exclude_logged_extents(struct btrfs_root *log,
6009 struct extent_buffer *eb)
6011 struct btrfs_file_extent_item *item;
6012 struct btrfs_key key;
6016 if (!btrfs_fs_incompat(log->fs_info, MIXED_GROUPS))
6019 for (i = 0; i < btrfs_header_nritems(eb); i++) {
6020 btrfs_item_key_to_cpu(eb, &key, i);
6021 if (key.type != BTRFS_EXTENT_DATA_KEY)
6023 item = btrfs_item_ptr(eb, i, struct btrfs_file_extent_item);
6024 found_type = btrfs_file_extent_type(eb, item);
6025 if (found_type == BTRFS_FILE_EXTENT_INLINE)
6027 if (btrfs_file_extent_disk_bytenr(eb, item) == 0)
6029 key.objectid = btrfs_file_extent_disk_bytenr(eb, item);
6030 key.offset = btrfs_file_extent_disk_num_bytes(eb, item);
6031 __exclude_logged_extent(log, key.objectid, key.offset);
6038 * btrfs_update_reserved_bytes - update the block_group and space info counters
6039 * @cache: The cache we are manipulating
6040 * @num_bytes: The number of bytes in question
6041 * @reserve: One of the reservation enums
6042 * @delalloc: The blocks are allocated for the delalloc write
6044 * This is called by the allocator when it reserves space, or by somebody who is
6045 * freeing space that was never actually used on disk. For example if you
6046 * reserve some space for a new leaf in transaction A and before transaction A
6047 * commits you free that leaf, you call this with reserve set to 0 in order to
6048 * clear the reservation.
6050 * Metadata reservations should be called with RESERVE_ALLOC so we do the proper
6051 * ENOSPC accounting. For data we handle the reservation through clearing the
6052 * delalloc bits in the io_tree. We have to do this since we could end up
6053 * allocating less disk space for the amount of data we have reserved in the
6054 * case of compression.
6056 * If this is a reservation and the block group has become read only we cannot
6057 * make the reservation and return -EAGAIN, otherwise this function always
6060 static int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache,
6061 u64 num_bytes, int reserve, int delalloc)
6063 struct btrfs_space_info *space_info = cache->space_info;
6066 spin_lock(&space_info->lock);
6067 spin_lock(&cache->lock);
6068 if (reserve != RESERVE_FREE) {
6072 cache->reserved += num_bytes;
6073 space_info->bytes_reserved += num_bytes;
6074 if (reserve == RESERVE_ALLOC) {
6075 trace_btrfs_space_reservation(cache->fs_info,
6076 "space_info", space_info->flags,
6078 space_info->bytes_may_use -= num_bytes;
6082 cache->delalloc_bytes += num_bytes;
6086 space_info->bytes_readonly += num_bytes;
6087 cache->reserved -= num_bytes;
6088 space_info->bytes_reserved -= num_bytes;
6091 cache->delalloc_bytes -= num_bytes;
6093 spin_unlock(&cache->lock);
6094 spin_unlock(&space_info->lock);
6098 void btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
6099 struct btrfs_root *root)
6101 struct btrfs_fs_info *fs_info = root->fs_info;
6102 struct btrfs_caching_control *next;
6103 struct btrfs_caching_control *caching_ctl;
6104 struct btrfs_block_group_cache *cache;
6106 down_write(&fs_info->commit_root_sem);
6108 list_for_each_entry_safe(caching_ctl, next,
6109 &fs_info->caching_block_groups, list) {
6110 cache = caching_ctl->block_group;
6111 if (block_group_cache_done(cache)) {
6112 cache->last_byte_to_unpin = (u64)-1;
6113 list_del_init(&caching_ctl->list);
6114 put_caching_control(caching_ctl);
6116 cache->last_byte_to_unpin = caching_ctl->progress;
6120 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
6121 fs_info->pinned_extents = &fs_info->freed_extents[1];
6123 fs_info->pinned_extents = &fs_info->freed_extents[0];
6125 up_write(&fs_info->commit_root_sem);
6127 update_global_block_rsv(fs_info);
6130 static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end,
6131 const bool return_free_space)
6133 struct btrfs_fs_info *fs_info = root->fs_info;
6134 struct btrfs_block_group_cache *cache = NULL;
6135 struct btrfs_space_info *space_info;
6136 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
6140 while (start <= end) {
6143 start >= cache->key.objectid + cache->key.offset) {
6145 btrfs_put_block_group(cache);
6146 cache = btrfs_lookup_block_group(fs_info, start);
6147 BUG_ON(!cache); /* Logic error */
6150 len = cache->key.objectid + cache->key.offset - start;
6151 len = min(len, end + 1 - start);
6153 if (start < cache->last_byte_to_unpin) {
6154 len = min(len, cache->last_byte_to_unpin - start);
6155 if (return_free_space)
6156 btrfs_add_free_space(cache, start, len);
6160 space_info = cache->space_info;
6162 spin_lock(&space_info->lock);
6163 spin_lock(&cache->lock);
6164 cache->pinned -= len;
6165 space_info->bytes_pinned -= len;
6166 percpu_counter_add(&space_info->total_bytes_pinned, -len);
6168 space_info->bytes_readonly += len;
6171 spin_unlock(&cache->lock);
6172 if (!readonly && global_rsv->space_info == space_info) {
6173 spin_lock(&global_rsv->lock);
6174 if (!global_rsv->full) {
6175 len = min(len, global_rsv->size -
6176 global_rsv->reserved);
6177 global_rsv->reserved += len;
6178 space_info->bytes_may_use += len;
6179 if (global_rsv->reserved >= global_rsv->size)
6180 global_rsv->full = 1;
6182 spin_unlock(&global_rsv->lock);
6184 spin_unlock(&space_info->lock);
6188 btrfs_put_block_group(cache);
6192 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
6193 struct btrfs_root *root)
6195 struct btrfs_fs_info *fs_info = root->fs_info;
6196 struct btrfs_block_group_cache *block_group, *tmp;
6197 struct list_head *deleted_bgs;
6198 struct extent_io_tree *unpin;
6203 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
6204 unpin = &fs_info->freed_extents[1];
6206 unpin = &fs_info->freed_extents[0];
6208 while (!trans->aborted) {
6209 mutex_lock(&fs_info->unused_bg_unpin_mutex);
6210 ret = find_first_extent_bit(unpin, 0, &start, &end,
6211 EXTENT_DIRTY, NULL);
6213 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
6217 if (btrfs_test_opt(root, DISCARD))
6218 ret = btrfs_discard_extent(root, start,
6219 end + 1 - start, NULL);
6221 clear_extent_dirty(unpin, start, end, GFP_NOFS);
6222 unpin_extent_range(root, start, end, true);
6223 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
6228 * Transaction is finished. We don't need the lock anymore. We
6229 * do need to clean up the block groups in case of a transaction
6232 deleted_bgs = &trans->transaction->deleted_bgs;
6233 list_for_each_entry_safe(block_group, tmp, deleted_bgs, bg_list) {
6237 if (!trans->aborted)
6238 ret = btrfs_discard_extent(root,
6239 block_group->key.objectid,
6240 block_group->key.offset,
6243 list_del_init(&block_group->bg_list);
6244 btrfs_put_block_group_trimming(block_group);
6245 btrfs_put_block_group(block_group);
6248 const char *errstr = btrfs_decode_error(ret);
6250 "Discard failed while removing blockgroup: errno=%d %s\n",
6258 static void add_pinned_bytes(struct btrfs_fs_info *fs_info, u64 num_bytes,
6259 u64 owner, u64 root_objectid)
6261 struct btrfs_space_info *space_info;
6264 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
6265 if (root_objectid == BTRFS_CHUNK_TREE_OBJECTID)
6266 flags = BTRFS_BLOCK_GROUP_SYSTEM;
6268 flags = BTRFS_BLOCK_GROUP_METADATA;
6270 flags = BTRFS_BLOCK_GROUP_DATA;
6273 space_info = __find_space_info(fs_info, flags);
6274 BUG_ON(!space_info); /* Logic bug */
6275 percpu_counter_add(&space_info->total_bytes_pinned, num_bytes);
6279 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
6280 struct btrfs_root *root,
6281 struct btrfs_delayed_ref_node *node, u64 parent,
6282 u64 root_objectid, u64 owner_objectid,
6283 u64 owner_offset, int refs_to_drop,
6284 struct btrfs_delayed_extent_op *extent_op)
6286 struct btrfs_key key;
6287 struct btrfs_path *path;
6288 struct btrfs_fs_info *info = root->fs_info;
6289 struct btrfs_root *extent_root = info->extent_root;
6290 struct extent_buffer *leaf;
6291 struct btrfs_extent_item *ei;
6292 struct btrfs_extent_inline_ref *iref;
6295 int extent_slot = 0;
6296 int found_extent = 0;
6298 int no_quota = node->no_quota;
6301 u64 bytenr = node->bytenr;
6302 u64 num_bytes = node->num_bytes;
6304 bool skinny_metadata = btrfs_fs_incompat(root->fs_info,
6307 if (!info->quota_enabled || !is_fstree(root_objectid))
6310 path = btrfs_alloc_path();
6315 path->leave_spinning = 1;
6317 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
6318 BUG_ON(!is_data && refs_to_drop != 1);
6321 skinny_metadata = 0;
6323 ret = lookup_extent_backref(trans, extent_root, path, &iref,
6324 bytenr, num_bytes, parent,
6325 root_objectid, owner_objectid,
6328 extent_slot = path->slots[0];
6329 while (extent_slot >= 0) {
6330 btrfs_item_key_to_cpu(path->nodes[0], &key,
6332 if (key.objectid != bytenr)
6334 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
6335 key.offset == num_bytes) {
6339 if (key.type == BTRFS_METADATA_ITEM_KEY &&
6340 key.offset == owner_objectid) {
6344 if (path->slots[0] - extent_slot > 5)
6348 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
6349 item_size = btrfs_item_size_nr(path->nodes[0], extent_slot);
6350 if (found_extent && item_size < sizeof(*ei))
6353 if (!found_extent) {
6355 ret = remove_extent_backref(trans, extent_root, path,
6357 is_data, &last_ref);
6359 btrfs_abort_transaction(trans, extent_root, ret);
6362 btrfs_release_path(path);
6363 path->leave_spinning = 1;
6365 key.objectid = bytenr;
6366 key.type = BTRFS_EXTENT_ITEM_KEY;
6367 key.offset = num_bytes;
6369 if (!is_data && skinny_metadata) {
6370 key.type = BTRFS_METADATA_ITEM_KEY;
6371 key.offset = owner_objectid;
6374 ret = btrfs_search_slot(trans, extent_root,
6376 if (ret > 0 && skinny_metadata && path->slots[0]) {
6378 * Couldn't find our skinny metadata item,
6379 * see if we have ye olde extent item.
6382 btrfs_item_key_to_cpu(path->nodes[0], &key,
6384 if (key.objectid == bytenr &&
6385 key.type == BTRFS_EXTENT_ITEM_KEY &&
6386 key.offset == num_bytes)
6390 if (ret > 0 && skinny_metadata) {
6391 skinny_metadata = false;
6392 key.objectid = bytenr;
6393 key.type = BTRFS_EXTENT_ITEM_KEY;
6394 key.offset = num_bytes;
6395 btrfs_release_path(path);
6396 ret = btrfs_search_slot(trans, extent_root,
6401 btrfs_err(info, "umm, got %d back from search, was looking for %llu",
6404 btrfs_print_leaf(extent_root,
6408 btrfs_abort_transaction(trans, extent_root, ret);
6411 extent_slot = path->slots[0];
6413 } else if (WARN_ON(ret == -ENOENT)) {
6414 btrfs_print_leaf(extent_root, path->nodes[0]);
6416 "unable to find ref byte nr %llu parent %llu root %llu owner %llu offset %llu",
6417 bytenr, parent, root_objectid, owner_objectid,
6419 btrfs_abort_transaction(trans, extent_root, ret);
6422 btrfs_abort_transaction(trans, extent_root, ret);
6426 leaf = path->nodes[0];
6427 item_size = btrfs_item_size_nr(leaf, extent_slot);
6428 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
6429 if (item_size < sizeof(*ei)) {
6430 BUG_ON(found_extent || extent_slot != path->slots[0]);
6431 ret = convert_extent_item_v0(trans, extent_root, path,
6434 btrfs_abort_transaction(trans, extent_root, ret);
6438 btrfs_release_path(path);
6439 path->leave_spinning = 1;
6441 key.objectid = bytenr;
6442 key.type = BTRFS_EXTENT_ITEM_KEY;
6443 key.offset = num_bytes;
6445 ret = btrfs_search_slot(trans, extent_root, &key, path,
6448 btrfs_err(info, "umm, got %d back from search, was looking for %llu",
6450 btrfs_print_leaf(extent_root, path->nodes[0]);
6453 btrfs_abort_transaction(trans, extent_root, ret);
6457 extent_slot = path->slots[0];
6458 leaf = path->nodes[0];
6459 item_size = btrfs_item_size_nr(leaf, extent_slot);
6462 BUG_ON(item_size < sizeof(*ei));
6463 ei = btrfs_item_ptr(leaf, extent_slot,
6464 struct btrfs_extent_item);
6465 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID &&
6466 key.type == BTRFS_EXTENT_ITEM_KEY) {
6467 struct btrfs_tree_block_info *bi;
6468 BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
6469 bi = (struct btrfs_tree_block_info *)(ei + 1);
6470 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
6473 refs = btrfs_extent_refs(leaf, ei);
6474 if (refs < refs_to_drop) {
6475 btrfs_err(info, "trying to drop %d refs but we only have %Lu "
6476 "for bytenr %Lu", refs_to_drop, refs, bytenr);
6478 btrfs_abort_transaction(trans, extent_root, ret);
6481 refs -= refs_to_drop;
6485 __run_delayed_extent_op(extent_op, leaf, ei);
6487 * In the case of inline back ref, reference count will
6488 * be updated by remove_extent_backref
6491 BUG_ON(!found_extent);
6493 btrfs_set_extent_refs(leaf, ei, refs);
6494 btrfs_mark_buffer_dirty(leaf);
6497 ret = remove_extent_backref(trans, extent_root, path,
6499 is_data, &last_ref);
6501 btrfs_abort_transaction(trans, extent_root, ret);
6505 add_pinned_bytes(root->fs_info, -num_bytes, owner_objectid,
6509 BUG_ON(is_data && refs_to_drop !=
6510 extent_data_ref_count(path, iref));
6512 BUG_ON(path->slots[0] != extent_slot);
6514 BUG_ON(path->slots[0] != extent_slot + 1);
6515 path->slots[0] = extent_slot;
6521 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
6524 btrfs_abort_transaction(trans, extent_root, ret);
6527 btrfs_release_path(path);
6530 ret = btrfs_del_csums(trans, root, bytenr, num_bytes);
6532 btrfs_abort_transaction(trans, extent_root, ret);
6537 ret = update_block_group(trans, root, bytenr, num_bytes, 0);
6539 btrfs_abort_transaction(trans, extent_root, ret);
6543 btrfs_release_path(path);
6546 btrfs_free_path(path);
6551 * when we free an block, it is possible (and likely) that we free the last
6552 * delayed ref for that extent as well. This searches the delayed ref tree for
6553 * a given extent, and if there are no other delayed refs to be processed, it
6554 * removes it from the tree.
6556 static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans,
6557 struct btrfs_root *root, u64 bytenr)
6559 struct btrfs_delayed_ref_head *head;
6560 struct btrfs_delayed_ref_root *delayed_refs;
6563 delayed_refs = &trans->transaction->delayed_refs;
6564 spin_lock(&delayed_refs->lock);
6565 head = btrfs_find_delayed_ref_head(trans, bytenr);
6567 goto out_delayed_unlock;
6569 spin_lock(&head->lock);
6570 if (!list_empty(&head->ref_list))
6573 if (head->extent_op) {
6574 if (!head->must_insert_reserved)
6576 btrfs_free_delayed_extent_op(head->extent_op);
6577 head->extent_op = NULL;
6581 * waiting for the lock here would deadlock. If someone else has it
6582 * locked they are already in the process of dropping it anyway
6584 if (!mutex_trylock(&head->mutex))
6588 * at this point we have a head with no other entries. Go
6589 * ahead and process it.
6591 head->node.in_tree = 0;
6592 rb_erase(&head->href_node, &delayed_refs->href_root);
6594 atomic_dec(&delayed_refs->num_entries);
6597 * we don't take a ref on the node because we're removing it from the
6598 * tree, so we just steal the ref the tree was holding.
6600 delayed_refs->num_heads--;
6601 if (head->processing == 0)
6602 delayed_refs->num_heads_ready--;
6603 head->processing = 0;
6604 spin_unlock(&head->lock);
6605 spin_unlock(&delayed_refs->lock);
6607 BUG_ON(head->extent_op);
6608 if (head->must_insert_reserved)
6611 mutex_unlock(&head->mutex);
6612 btrfs_put_delayed_ref(&head->node);
6615 spin_unlock(&head->lock);
6618 spin_unlock(&delayed_refs->lock);
6622 void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
6623 struct btrfs_root *root,
6624 struct extent_buffer *buf,
6625 u64 parent, int last_ref)
6630 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
6631 ret = btrfs_add_delayed_tree_ref(root->fs_info, trans,
6632 buf->start, buf->len,
6633 parent, root->root_key.objectid,
6634 btrfs_header_level(buf),
6635 BTRFS_DROP_DELAYED_REF, NULL, 0);
6636 BUG_ON(ret); /* -ENOMEM */
6642 if (btrfs_header_generation(buf) == trans->transid) {
6643 struct btrfs_block_group_cache *cache;
6645 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
6646 ret = check_ref_cleanup(trans, root, buf->start);
6651 cache = btrfs_lookup_block_group(root->fs_info, buf->start);
6653 if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
6654 pin_down_extent(root, cache, buf->start, buf->len, 1);
6655 btrfs_put_block_group(cache);
6659 WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags));
6661 btrfs_add_free_space(cache, buf->start, buf->len);
6662 btrfs_update_reserved_bytes(cache, buf->len, RESERVE_FREE, 0);
6663 btrfs_put_block_group(cache);
6664 trace_btrfs_reserved_extent_free(root, buf->start, buf->len);
6669 add_pinned_bytes(root->fs_info, buf->len,
6670 btrfs_header_level(buf),
6671 root->root_key.objectid);
6674 * Deleting the buffer, clear the corrupt flag since it doesn't matter
6677 clear_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags);
6680 /* Can return -ENOMEM */
6681 int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root *root,
6682 u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid,
6683 u64 owner, u64 offset, int no_quota)
6686 struct btrfs_fs_info *fs_info = root->fs_info;
6688 if (btrfs_test_is_dummy_root(root))
6691 add_pinned_bytes(root->fs_info, num_bytes, owner, root_objectid);
6694 * tree log blocks never actually go into the extent allocation
6695 * tree, just update pinning info and exit early.
6697 if (root_objectid == BTRFS_TREE_LOG_OBJECTID) {
6698 WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID);
6699 /* unlocks the pinned mutex */
6700 btrfs_pin_extent(root, bytenr, num_bytes, 1);
6702 } else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
6703 ret = btrfs_add_delayed_tree_ref(fs_info, trans, bytenr,
6705 parent, root_objectid, (int)owner,
6706 BTRFS_DROP_DELAYED_REF, NULL, no_quota);
6708 ret = btrfs_add_delayed_data_ref(fs_info, trans, bytenr,
6710 parent, root_objectid, owner,
6711 offset, BTRFS_DROP_DELAYED_REF,
6718 * when we wait for progress in the block group caching, its because
6719 * our allocation attempt failed at least once. So, we must sleep
6720 * and let some progress happen before we try again.
6722 * This function will sleep at least once waiting for new free space to
6723 * show up, and then it will check the block group free space numbers
6724 * for our min num_bytes. Another option is to have it go ahead
6725 * and look in the rbtree for a free extent of a given size, but this
6728 * Callers of this must check if cache->cached == BTRFS_CACHE_ERROR before using
6729 * any of the information in this block group.
6731 static noinline void
6732 wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
6735 struct btrfs_caching_control *caching_ctl;
6737 caching_ctl = get_caching_control(cache);
6741 wait_event(caching_ctl->wait, block_group_cache_done(cache) ||
6742 (cache->free_space_ctl->free_space >= num_bytes));
6744 put_caching_control(caching_ctl);
6748 wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
6750 struct btrfs_caching_control *caching_ctl;
6753 caching_ctl = get_caching_control(cache);
6755 return (cache->cached == BTRFS_CACHE_ERROR) ? -EIO : 0;
6757 wait_event(caching_ctl->wait, block_group_cache_done(cache));
6758 if (cache->cached == BTRFS_CACHE_ERROR)
6760 put_caching_control(caching_ctl);
6764 int __get_raid_index(u64 flags)
6766 if (flags & BTRFS_BLOCK_GROUP_RAID10)
6767 return BTRFS_RAID_RAID10;
6768 else if (flags & BTRFS_BLOCK_GROUP_RAID1)
6769 return BTRFS_RAID_RAID1;
6770 else if (flags & BTRFS_BLOCK_GROUP_DUP)
6771 return BTRFS_RAID_DUP;
6772 else if (flags & BTRFS_BLOCK_GROUP_RAID0)
6773 return BTRFS_RAID_RAID0;
6774 else if (flags & BTRFS_BLOCK_GROUP_RAID5)
6775 return BTRFS_RAID_RAID5;
6776 else if (flags & BTRFS_BLOCK_GROUP_RAID6)
6777 return BTRFS_RAID_RAID6;
6779 return BTRFS_RAID_SINGLE; /* BTRFS_BLOCK_GROUP_SINGLE */
6782 int get_block_group_index(struct btrfs_block_group_cache *cache)
6784 return __get_raid_index(cache->flags);
6787 static const char *btrfs_raid_type_names[BTRFS_NR_RAID_TYPES] = {
6788 [BTRFS_RAID_RAID10] = "raid10",
6789 [BTRFS_RAID_RAID1] = "raid1",
6790 [BTRFS_RAID_DUP] = "dup",
6791 [BTRFS_RAID_RAID0] = "raid0",
6792 [BTRFS_RAID_SINGLE] = "single",
6793 [BTRFS_RAID_RAID5] = "raid5",
6794 [BTRFS_RAID_RAID6] = "raid6",
6797 static const char *get_raid_name(enum btrfs_raid_types type)
6799 if (type >= BTRFS_NR_RAID_TYPES)
6802 return btrfs_raid_type_names[type];
6805 enum btrfs_loop_type {
6806 LOOP_CACHING_NOWAIT = 0,
6807 LOOP_CACHING_WAIT = 1,
6808 LOOP_ALLOC_CHUNK = 2,
6809 LOOP_NO_EMPTY_SIZE = 3,
6813 btrfs_lock_block_group(struct btrfs_block_group_cache *cache,
6817 down_read(&cache->data_rwsem);
6821 btrfs_grab_block_group(struct btrfs_block_group_cache *cache,
6824 btrfs_get_block_group(cache);
6826 down_read(&cache->data_rwsem);
6829 static struct btrfs_block_group_cache *
6830 btrfs_lock_cluster(struct btrfs_block_group_cache *block_group,
6831 struct btrfs_free_cluster *cluster,
6834 struct btrfs_block_group_cache *used_bg;
6835 bool locked = false;
6837 spin_lock(&cluster->refill_lock);
6839 if (used_bg == cluster->block_group)
6842 up_read(&used_bg->data_rwsem);
6843 btrfs_put_block_group(used_bg);
6846 used_bg = cluster->block_group;
6850 if (used_bg == block_group)
6853 btrfs_get_block_group(used_bg);
6858 if (down_read_trylock(&used_bg->data_rwsem))
6861 spin_unlock(&cluster->refill_lock);
6862 down_read(&used_bg->data_rwsem);
6868 btrfs_release_block_group(struct btrfs_block_group_cache *cache,
6872 up_read(&cache->data_rwsem);
6873 btrfs_put_block_group(cache);
6877 * walks the btree of allocated extents and find a hole of a given size.
6878 * The key ins is changed to record the hole:
6879 * ins->objectid == start position
6880 * ins->flags = BTRFS_EXTENT_ITEM_KEY
6881 * ins->offset == the size of the hole.
6882 * Any available blocks before search_start are skipped.
6884 * If there is no suitable free space, we will record the max size of
6885 * the free space extent currently.
6887 static noinline int find_free_extent(struct btrfs_root *orig_root,
6888 u64 num_bytes, u64 empty_size,
6889 u64 hint_byte, struct btrfs_key *ins,
6890 u64 flags, int delalloc)
6893 struct btrfs_root *root = orig_root->fs_info->extent_root;
6894 struct btrfs_free_cluster *last_ptr = NULL;
6895 struct btrfs_block_group_cache *block_group = NULL;
6896 u64 search_start = 0;
6897 u64 max_extent_size = 0;
6898 int empty_cluster = 2 * 1024 * 1024;
6899 struct btrfs_space_info *space_info;
6901 int index = __get_raid_index(flags);
6902 int alloc_type = (flags & BTRFS_BLOCK_GROUP_DATA) ?
6903 RESERVE_ALLOC_NO_ACCOUNT : RESERVE_ALLOC;
6904 bool failed_cluster_refill = false;
6905 bool failed_alloc = false;
6906 bool use_cluster = true;
6907 bool have_caching_bg = false;
6909 WARN_ON(num_bytes < root->sectorsize);
6910 ins->type = BTRFS_EXTENT_ITEM_KEY;
6914 trace_find_free_extent(orig_root, num_bytes, empty_size, flags);
6916 space_info = __find_space_info(root->fs_info, flags);
6918 btrfs_err(root->fs_info, "No space info for %llu", flags);
6923 * If the space info is for both data and metadata it means we have a
6924 * small filesystem and we can't use the clustering stuff.
6926 if (btrfs_mixed_space_info(space_info))
6927 use_cluster = false;
6929 if (flags & BTRFS_BLOCK_GROUP_METADATA && use_cluster) {
6930 last_ptr = &root->fs_info->meta_alloc_cluster;
6931 if (!btrfs_test_opt(root, SSD))
6932 empty_cluster = 64 * 1024;
6935 if ((flags & BTRFS_BLOCK_GROUP_DATA) && use_cluster &&
6936 btrfs_test_opt(root, SSD)) {
6937 last_ptr = &root->fs_info->data_alloc_cluster;
6941 spin_lock(&last_ptr->lock);
6942 if (last_ptr->block_group)
6943 hint_byte = last_ptr->window_start;
6944 spin_unlock(&last_ptr->lock);
6947 search_start = max(search_start, first_logical_byte(root, 0));
6948 search_start = max(search_start, hint_byte);
6953 if (search_start == hint_byte) {
6954 block_group = btrfs_lookup_block_group(root->fs_info,
6957 * we don't want to use the block group if it doesn't match our
6958 * allocation bits, or if its not cached.
6960 * However if we are re-searching with an ideal block group
6961 * picked out then we don't care that the block group is cached.
6963 if (block_group && block_group_bits(block_group, flags) &&
6964 block_group->cached != BTRFS_CACHE_NO) {
6965 down_read(&space_info->groups_sem);
6966 if (list_empty(&block_group->list) ||
6969 * someone is removing this block group,
6970 * we can't jump into the have_block_group
6971 * target because our list pointers are not
6974 btrfs_put_block_group(block_group);
6975 up_read(&space_info->groups_sem);
6977 index = get_block_group_index(block_group);
6978 btrfs_lock_block_group(block_group, delalloc);
6979 goto have_block_group;
6981 } else if (block_group) {
6982 btrfs_put_block_group(block_group);
6986 have_caching_bg = false;
6987 down_read(&space_info->groups_sem);
6988 list_for_each_entry(block_group, &space_info->block_groups[index],
6993 btrfs_grab_block_group(block_group, delalloc);
6994 search_start = block_group->key.objectid;
6997 * this can happen if we end up cycling through all the
6998 * raid types, but we want to make sure we only allocate
6999 * for the proper type.
7001 if (!block_group_bits(block_group, flags)) {
7002 u64 extra = BTRFS_BLOCK_GROUP_DUP |
7003 BTRFS_BLOCK_GROUP_RAID1 |
7004 BTRFS_BLOCK_GROUP_RAID5 |
7005 BTRFS_BLOCK_GROUP_RAID6 |
7006 BTRFS_BLOCK_GROUP_RAID10;
7009 * if they asked for extra copies and this block group
7010 * doesn't provide them, bail. This does allow us to
7011 * fill raid0 from raid1.
7013 if ((flags & extra) && !(block_group->flags & extra))
7018 cached = block_group_cache_done(block_group);
7019 if (unlikely(!cached)) {
7020 ret = cache_block_group(block_group, 0);
7025 if (unlikely(block_group->cached == BTRFS_CACHE_ERROR))
7027 if (unlikely(block_group->ro))
7031 * Ok we want to try and use the cluster allocator, so
7035 struct btrfs_block_group_cache *used_block_group;
7036 unsigned long aligned_cluster;
7038 * the refill lock keeps out other
7039 * people trying to start a new cluster
7041 used_block_group = btrfs_lock_cluster(block_group,
7044 if (!used_block_group)
7045 goto refill_cluster;
7047 if (used_block_group != block_group &&
7048 (used_block_group->ro ||
7049 !block_group_bits(used_block_group, flags)))
7050 goto release_cluster;
7052 offset = btrfs_alloc_from_cluster(used_block_group,
7055 used_block_group->key.objectid,
7058 /* we have a block, we're done */
7059 spin_unlock(&last_ptr->refill_lock);
7060 trace_btrfs_reserve_extent_cluster(root,
7062 search_start, num_bytes);
7063 if (used_block_group != block_group) {
7064 btrfs_release_block_group(block_group,
7066 block_group = used_block_group;
7071 WARN_ON(last_ptr->block_group != used_block_group);
7073 /* If we are on LOOP_NO_EMPTY_SIZE, we can't
7074 * set up a new clusters, so lets just skip it
7075 * and let the allocator find whatever block
7076 * it can find. If we reach this point, we
7077 * will have tried the cluster allocator
7078 * plenty of times and not have found
7079 * anything, so we are likely way too
7080 * fragmented for the clustering stuff to find
7083 * However, if the cluster is taken from the
7084 * current block group, release the cluster
7085 * first, so that we stand a better chance of
7086 * succeeding in the unclustered
7088 if (loop >= LOOP_NO_EMPTY_SIZE &&
7089 used_block_group != block_group) {
7090 spin_unlock(&last_ptr->refill_lock);
7091 btrfs_release_block_group(used_block_group,
7093 goto unclustered_alloc;
7097 * this cluster didn't work out, free it and
7100 btrfs_return_cluster_to_free_space(NULL, last_ptr);
7102 if (used_block_group != block_group)
7103 btrfs_release_block_group(used_block_group,
7106 if (loop >= LOOP_NO_EMPTY_SIZE) {
7107 spin_unlock(&last_ptr->refill_lock);
7108 goto unclustered_alloc;
7111 aligned_cluster = max_t(unsigned long,
7112 empty_cluster + empty_size,
7113 block_group->full_stripe_len);
7115 /* allocate a cluster in this block group */
7116 ret = btrfs_find_space_cluster(root, block_group,
7117 last_ptr, search_start,
7122 * now pull our allocation out of this
7125 offset = btrfs_alloc_from_cluster(block_group,
7131 /* we found one, proceed */
7132 spin_unlock(&last_ptr->refill_lock);
7133 trace_btrfs_reserve_extent_cluster(root,
7134 block_group, search_start,
7138 } else if (!cached && loop > LOOP_CACHING_NOWAIT
7139 && !failed_cluster_refill) {
7140 spin_unlock(&last_ptr->refill_lock);
7142 failed_cluster_refill = true;
7143 wait_block_group_cache_progress(block_group,
7144 num_bytes + empty_cluster + empty_size);
7145 goto have_block_group;
7149 * at this point we either didn't find a cluster
7150 * or we weren't able to allocate a block from our
7151 * cluster. Free the cluster we've been trying
7152 * to use, and go to the next block group
7154 btrfs_return_cluster_to_free_space(NULL, last_ptr);
7155 spin_unlock(&last_ptr->refill_lock);
7160 spin_lock(&block_group->free_space_ctl->tree_lock);
7162 block_group->free_space_ctl->free_space <
7163 num_bytes + empty_cluster + empty_size) {
7164 if (block_group->free_space_ctl->free_space >
7167 block_group->free_space_ctl->free_space;
7168 spin_unlock(&block_group->free_space_ctl->tree_lock);
7171 spin_unlock(&block_group->free_space_ctl->tree_lock);
7173 offset = btrfs_find_space_for_alloc(block_group, search_start,
7174 num_bytes, empty_size,
7177 * If we didn't find a chunk, and we haven't failed on this
7178 * block group before, and this block group is in the middle of
7179 * caching and we are ok with waiting, then go ahead and wait
7180 * for progress to be made, and set failed_alloc to true.
7182 * If failed_alloc is true then we've already waited on this
7183 * block group once and should move on to the next block group.
7185 if (!offset && !failed_alloc && !cached &&
7186 loop > LOOP_CACHING_NOWAIT) {
7187 wait_block_group_cache_progress(block_group,
7188 num_bytes + empty_size);
7189 failed_alloc = true;
7190 goto have_block_group;
7191 } else if (!offset) {
7193 have_caching_bg = true;
7197 search_start = ALIGN(offset, root->stripesize);
7199 /* move on to the next group */
7200 if (search_start + num_bytes >
7201 block_group->key.objectid + block_group->key.offset) {
7202 btrfs_add_free_space(block_group, offset, num_bytes);
7206 if (offset < search_start)
7207 btrfs_add_free_space(block_group, offset,
7208 search_start - offset);
7209 BUG_ON(offset > search_start);
7211 ret = btrfs_update_reserved_bytes(block_group, num_bytes,
7212 alloc_type, delalloc);
7213 if (ret == -EAGAIN) {
7214 btrfs_add_free_space(block_group, offset, num_bytes);
7218 /* we are all good, lets return */
7219 ins->objectid = search_start;
7220 ins->offset = num_bytes;
7222 trace_btrfs_reserve_extent(orig_root, block_group,
7223 search_start, num_bytes);
7224 btrfs_release_block_group(block_group, delalloc);
7227 failed_cluster_refill = false;
7228 failed_alloc = false;
7229 BUG_ON(index != get_block_group_index(block_group));
7230 btrfs_release_block_group(block_group, delalloc);
7232 up_read(&space_info->groups_sem);
7234 if (!ins->objectid && loop >= LOOP_CACHING_WAIT && have_caching_bg)
7237 if (!ins->objectid && ++index < BTRFS_NR_RAID_TYPES)
7241 * LOOP_CACHING_NOWAIT, search partially cached block groups, kicking
7242 * caching kthreads as we move along
7243 * LOOP_CACHING_WAIT, search everything, and wait if our bg is caching
7244 * LOOP_ALLOC_CHUNK, force a chunk allocation and try again
7245 * LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try
7248 if (!ins->objectid && loop < LOOP_NO_EMPTY_SIZE) {
7251 if (loop == LOOP_ALLOC_CHUNK) {
7252 struct btrfs_trans_handle *trans;
7255 trans = current->journal_info;
7259 trans = btrfs_join_transaction(root);
7261 if (IS_ERR(trans)) {
7262 ret = PTR_ERR(trans);
7266 ret = do_chunk_alloc(trans, root, flags,
7269 * Do not bail out on ENOSPC since we
7270 * can do more things.
7272 if (ret < 0 && ret != -ENOSPC)
7273 btrfs_abort_transaction(trans,
7278 btrfs_end_transaction(trans, root);
7283 if (loop == LOOP_NO_EMPTY_SIZE) {
7289 } else if (!ins->objectid) {
7291 } else if (ins->objectid) {
7296 ins->offset = max_extent_size;
7300 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
7301 int dump_block_groups)
7303 struct btrfs_block_group_cache *cache;
7306 spin_lock(&info->lock);
7307 printk(KERN_INFO "BTRFS: space_info %llu has %llu free, is %sfull\n",
7309 info->total_bytes - info->bytes_used - info->bytes_pinned -
7310 info->bytes_reserved - info->bytes_readonly,
7311 (info->full) ? "" : "not ");
7312 printk(KERN_INFO "BTRFS: space_info total=%llu, used=%llu, pinned=%llu, "
7313 "reserved=%llu, may_use=%llu, readonly=%llu\n",
7314 info->total_bytes, info->bytes_used, info->bytes_pinned,
7315 info->bytes_reserved, info->bytes_may_use,
7316 info->bytes_readonly);
7317 spin_unlock(&info->lock);
7319 if (!dump_block_groups)
7322 down_read(&info->groups_sem);
7324 list_for_each_entry(cache, &info->block_groups[index], list) {
7325 spin_lock(&cache->lock);
7326 printk(KERN_INFO "BTRFS: "
7327 "block group %llu has %llu bytes, "
7328 "%llu used %llu pinned %llu reserved %s\n",
7329 cache->key.objectid, cache->key.offset,
7330 btrfs_block_group_used(&cache->item), cache->pinned,
7331 cache->reserved, cache->ro ? "[readonly]" : "");
7332 btrfs_dump_free_space(cache, bytes);
7333 spin_unlock(&cache->lock);
7335 if (++index < BTRFS_NR_RAID_TYPES)
7337 up_read(&info->groups_sem);
7340 int btrfs_reserve_extent(struct btrfs_root *root,
7341 u64 num_bytes, u64 min_alloc_size,
7342 u64 empty_size, u64 hint_byte,
7343 struct btrfs_key *ins, int is_data, int delalloc)
7345 bool final_tried = false;
7349 flags = btrfs_get_alloc_profile(root, is_data);
7351 WARN_ON(num_bytes < root->sectorsize);
7352 ret = find_free_extent(root, num_bytes, empty_size, hint_byte, ins,
7355 if (ret == -ENOSPC) {
7356 if (!final_tried && ins->offset) {
7357 num_bytes = min(num_bytes >> 1, ins->offset);
7358 num_bytes = round_down(num_bytes, root->sectorsize);
7359 num_bytes = max(num_bytes, min_alloc_size);
7360 if (num_bytes == min_alloc_size)
7363 } else if (btrfs_test_opt(root, ENOSPC_DEBUG)) {
7364 struct btrfs_space_info *sinfo;
7366 sinfo = __find_space_info(root->fs_info, flags);
7367 btrfs_err(root->fs_info, "allocation failed flags %llu, wanted %llu",
7370 dump_space_info(sinfo, num_bytes, 1);
7377 static int __btrfs_free_reserved_extent(struct btrfs_root *root,
7379 int pin, int delalloc)
7381 struct btrfs_block_group_cache *cache;
7384 cache = btrfs_lookup_block_group(root->fs_info, start);
7386 btrfs_err(root->fs_info, "Unable to find block group for %llu",
7392 pin_down_extent(root, cache, start, len, 1);
7394 if (btrfs_test_opt(root, DISCARD))
7395 ret = btrfs_discard_extent(root, start, len, NULL);
7396 btrfs_add_free_space(cache, start, len);
7397 btrfs_update_reserved_bytes(cache, len, RESERVE_FREE, delalloc);
7400 btrfs_put_block_group(cache);
7402 trace_btrfs_reserved_extent_free(root, start, len);
7407 int btrfs_free_reserved_extent(struct btrfs_root *root,
7408 u64 start, u64 len, int delalloc)
7410 return __btrfs_free_reserved_extent(root, start, len, 0, delalloc);
7413 int btrfs_free_and_pin_reserved_extent(struct btrfs_root *root,
7416 return __btrfs_free_reserved_extent(root, start, len, 1, 0);
7419 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
7420 struct btrfs_root *root,
7421 u64 parent, u64 root_objectid,
7422 u64 flags, u64 owner, u64 offset,
7423 struct btrfs_key *ins, int ref_mod)
7426 struct btrfs_fs_info *fs_info = root->fs_info;
7427 struct btrfs_extent_item *extent_item;
7428 struct btrfs_extent_inline_ref *iref;
7429 struct btrfs_path *path;
7430 struct extent_buffer *leaf;
7435 type = BTRFS_SHARED_DATA_REF_KEY;
7437 type = BTRFS_EXTENT_DATA_REF_KEY;
7439 size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type);
7441 path = btrfs_alloc_path();
7445 path->leave_spinning = 1;
7446 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
7449 btrfs_free_path(path);
7453 leaf = path->nodes[0];
7454 extent_item = btrfs_item_ptr(leaf, path->slots[0],
7455 struct btrfs_extent_item);
7456 btrfs_set_extent_refs(leaf, extent_item, ref_mod);
7457 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
7458 btrfs_set_extent_flags(leaf, extent_item,
7459 flags | BTRFS_EXTENT_FLAG_DATA);
7461 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
7462 btrfs_set_extent_inline_ref_type(leaf, iref, type);
7464 struct btrfs_shared_data_ref *ref;
7465 ref = (struct btrfs_shared_data_ref *)(iref + 1);
7466 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
7467 btrfs_set_shared_data_ref_count(leaf, ref, ref_mod);
7469 struct btrfs_extent_data_ref *ref;
7470 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
7471 btrfs_set_extent_data_ref_root(leaf, ref, root_objectid);
7472 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
7473 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
7474 btrfs_set_extent_data_ref_count(leaf, ref, ref_mod);
7477 btrfs_mark_buffer_dirty(path->nodes[0]);
7478 btrfs_free_path(path);
7480 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
7481 if (ret) { /* -ENOENT, logic error */
7482 btrfs_err(fs_info, "update block group failed for %llu %llu",
7483 ins->objectid, ins->offset);
7486 trace_btrfs_reserved_extent_alloc(root, ins->objectid, ins->offset);
7490 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
7491 struct btrfs_root *root,
7492 u64 parent, u64 root_objectid,
7493 u64 flags, struct btrfs_disk_key *key,
7494 int level, struct btrfs_key *ins,
7498 struct btrfs_fs_info *fs_info = root->fs_info;
7499 struct btrfs_extent_item *extent_item;
7500 struct btrfs_tree_block_info *block_info;
7501 struct btrfs_extent_inline_ref *iref;
7502 struct btrfs_path *path;
7503 struct extent_buffer *leaf;
7504 u32 size = sizeof(*extent_item) + sizeof(*iref);
7505 u64 num_bytes = ins->offset;
7506 bool skinny_metadata = btrfs_fs_incompat(root->fs_info,
7509 if (!skinny_metadata)
7510 size += sizeof(*block_info);
7512 path = btrfs_alloc_path();
7514 btrfs_free_and_pin_reserved_extent(root, ins->objectid,
7519 path->leave_spinning = 1;
7520 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
7523 btrfs_free_path(path);
7524 btrfs_free_and_pin_reserved_extent(root, ins->objectid,
7529 leaf = path->nodes[0];
7530 extent_item = btrfs_item_ptr(leaf, path->slots[0],
7531 struct btrfs_extent_item);
7532 btrfs_set_extent_refs(leaf, extent_item, 1);
7533 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
7534 btrfs_set_extent_flags(leaf, extent_item,
7535 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
7537 if (skinny_metadata) {
7538 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
7539 num_bytes = root->nodesize;
7541 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
7542 btrfs_set_tree_block_key(leaf, block_info, key);
7543 btrfs_set_tree_block_level(leaf, block_info, level);
7544 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
7548 BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF));
7549 btrfs_set_extent_inline_ref_type(leaf, iref,
7550 BTRFS_SHARED_BLOCK_REF_KEY);
7551 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
7553 btrfs_set_extent_inline_ref_type(leaf, iref,
7554 BTRFS_TREE_BLOCK_REF_KEY);
7555 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
7558 btrfs_mark_buffer_dirty(leaf);
7559 btrfs_free_path(path);
7561 ret = update_block_group(trans, root, ins->objectid, root->nodesize,
7563 if (ret) { /* -ENOENT, logic error */
7564 btrfs_err(fs_info, "update block group failed for %llu %llu",
7565 ins->objectid, ins->offset);
7569 trace_btrfs_reserved_extent_alloc(root, ins->objectid, root->nodesize);
7573 int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
7574 struct btrfs_root *root,
7575 u64 root_objectid, u64 owner,
7576 u64 offset, struct btrfs_key *ins)
7580 BUG_ON(root_objectid == BTRFS_TREE_LOG_OBJECTID);
7582 ret = btrfs_add_delayed_data_ref(root->fs_info, trans, ins->objectid,
7584 root_objectid, owner, offset,
7585 BTRFS_ADD_DELAYED_EXTENT, NULL, 0);
7590 * this is used by the tree logging recovery code. It records that
7591 * an extent has been allocated and makes sure to clear the free
7592 * space cache bits as well
7594 int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
7595 struct btrfs_root *root,
7596 u64 root_objectid, u64 owner, u64 offset,
7597 struct btrfs_key *ins)
7600 struct btrfs_block_group_cache *block_group;
7603 * Mixed block groups will exclude before processing the log so we only
7604 * need to do the exlude dance if this fs isn't mixed.
7606 if (!btrfs_fs_incompat(root->fs_info, MIXED_GROUPS)) {
7607 ret = __exclude_logged_extent(root, ins->objectid, ins->offset);
7612 block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
7616 ret = btrfs_update_reserved_bytes(block_group, ins->offset,
7617 RESERVE_ALLOC_NO_ACCOUNT, 0);
7618 BUG_ON(ret); /* logic error */
7619 ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,
7620 0, owner, offset, ins, 1);
7621 btrfs_put_block_group(block_group);
7625 static struct extent_buffer *
7626 btrfs_init_new_buffer(struct btrfs_trans_handle *trans, struct btrfs_root *root,
7627 u64 bytenr, int level)
7629 struct extent_buffer *buf;
7631 buf = btrfs_find_create_tree_block(root, bytenr);
7633 return ERR_PTR(-ENOMEM);
7634 btrfs_set_header_generation(buf, trans->transid);
7635 btrfs_set_buffer_lockdep_class(root->root_key.objectid, buf, level);
7636 btrfs_tree_lock(buf);
7637 clean_tree_block(trans, root->fs_info, buf);
7638 clear_bit(EXTENT_BUFFER_STALE, &buf->bflags);
7640 btrfs_set_lock_blocking(buf);
7641 btrfs_set_buffer_uptodate(buf);
7643 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
7644 buf->log_index = root->log_transid % 2;
7646 * we allow two log transactions at a time, use different
7647 * EXENT bit to differentiate dirty pages.
7649 if (buf->log_index == 0)
7650 set_extent_dirty(&root->dirty_log_pages, buf->start,
7651 buf->start + buf->len - 1, GFP_NOFS);
7653 set_extent_new(&root->dirty_log_pages, buf->start,
7654 buf->start + buf->len - 1, GFP_NOFS);
7656 buf->log_index = -1;
7657 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
7658 buf->start + buf->len - 1, GFP_NOFS);
7660 trans->blocks_used++;
7661 /* this returns a buffer locked for blocking */
7665 static struct btrfs_block_rsv *
7666 use_block_rsv(struct btrfs_trans_handle *trans,
7667 struct btrfs_root *root, u32 blocksize)
7669 struct btrfs_block_rsv *block_rsv;
7670 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
7672 bool global_updated = false;
7674 block_rsv = get_block_rsv(trans, root);
7676 if (unlikely(block_rsv->size == 0))
7679 ret = block_rsv_use_bytes(block_rsv, blocksize);
7683 if (block_rsv->failfast)
7684 return ERR_PTR(ret);
7686 if (block_rsv->type == BTRFS_BLOCK_RSV_GLOBAL && !global_updated) {
7687 global_updated = true;
7688 update_global_block_rsv(root->fs_info);
7692 if (btrfs_test_opt(root, ENOSPC_DEBUG)) {
7693 static DEFINE_RATELIMIT_STATE(_rs,
7694 DEFAULT_RATELIMIT_INTERVAL * 10,
7695 /*DEFAULT_RATELIMIT_BURST*/ 1);
7696 if (__ratelimit(&_rs))
7698 "BTRFS: block rsv returned %d\n", ret);
7701 ret = reserve_metadata_bytes(root, block_rsv, blocksize,
7702 BTRFS_RESERVE_NO_FLUSH);
7706 * If we couldn't reserve metadata bytes try and use some from
7707 * the global reserve if its space type is the same as the global
7710 if (block_rsv->type != BTRFS_BLOCK_RSV_GLOBAL &&
7711 block_rsv->space_info == global_rsv->space_info) {
7712 ret = block_rsv_use_bytes(global_rsv, blocksize);
7716 return ERR_PTR(ret);
7719 static void unuse_block_rsv(struct btrfs_fs_info *fs_info,
7720 struct btrfs_block_rsv *block_rsv, u32 blocksize)
7722 block_rsv_add_bytes(block_rsv, blocksize, 0);
7723 block_rsv_release_bytes(fs_info, block_rsv, NULL, 0);
7727 * finds a free extent and does all the dirty work required for allocation
7728 * returns the tree buffer or an ERR_PTR on error.
7730 struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans,
7731 struct btrfs_root *root,
7732 u64 parent, u64 root_objectid,
7733 struct btrfs_disk_key *key, int level,
7734 u64 hint, u64 empty_size)
7736 struct btrfs_key ins;
7737 struct btrfs_block_rsv *block_rsv;
7738 struct extent_buffer *buf;
7739 struct btrfs_delayed_extent_op *extent_op;
7742 u32 blocksize = root->nodesize;
7743 bool skinny_metadata = btrfs_fs_incompat(root->fs_info,
7746 if (btrfs_test_is_dummy_root(root)) {
7747 buf = btrfs_init_new_buffer(trans, root, root->alloc_bytenr,
7750 root->alloc_bytenr += blocksize;
7754 block_rsv = use_block_rsv(trans, root, blocksize);
7755 if (IS_ERR(block_rsv))
7756 return ERR_CAST(block_rsv);
7758 ret = btrfs_reserve_extent(root, blocksize, blocksize,
7759 empty_size, hint, &ins, 0, 0);
7763 buf = btrfs_init_new_buffer(trans, root, ins.objectid, level);
7766 goto out_free_reserved;
7769 if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
7771 parent = ins.objectid;
7772 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
7776 if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
7777 extent_op = btrfs_alloc_delayed_extent_op();
7783 memcpy(&extent_op->key, key, sizeof(extent_op->key));
7785 memset(&extent_op->key, 0, sizeof(extent_op->key));
7786 extent_op->flags_to_set = flags;
7787 if (skinny_metadata)
7788 extent_op->update_key = 0;
7790 extent_op->update_key = 1;
7791 extent_op->update_flags = 1;
7792 extent_op->is_data = 0;
7793 extent_op->level = level;
7795 ret = btrfs_add_delayed_tree_ref(root->fs_info, trans,
7796 ins.objectid, ins.offset,
7797 parent, root_objectid, level,
7798 BTRFS_ADD_DELAYED_EXTENT,
7801 goto out_free_delayed;
7806 btrfs_free_delayed_extent_op(extent_op);
7808 free_extent_buffer(buf);
7810 btrfs_free_reserved_extent(root, ins.objectid, ins.offset, 0);
7812 unuse_block_rsv(root->fs_info, block_rsv, blocksize);
7813 return ERR_PTR(ret);
7816 struct walk_control {
7817 u64 refs[BTRFS_MAX_LEVEL];
7818 u64 flags[BTRFS_MAX_LEVEL];
7819 struct btrfs_key update_progress;
7830 #define DROP_REFERENCE 1
7831 #define UPDATE_BACKREF 2
7833 static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
7834 struct btrfs_root *root,
7835 struct walk_control *wc,
7836 struct btrfs_path *path)
7844 struct btrfs_key key;
7845 struct extent_buffer *eb;
7850 if (path->slots[wc->level] < wc->reada_slot) {
7851 wc->reada_count = wc->reada_count * 2 / 3;
7852 wc->reada_count = max(wc->reada_count, 2);
7854 wc->reada_count = wc->reada_count * 3 / 2;
7855 wc->reada_count = min_t(int, wc->reada_count,
7856 BTRFS_NODEPTRS_PER_BLOCK(root));
7859 eb = path->nodes[wc->level];
7860 nritems = btrfs_header_nritems(eb);
7861 blocksize = root->nodesize;
7863 for (slot = path->slots[wc->level]; slot < nritems; slot++) {
7864 if (nread >= wc->reada_count)
7868 bytenr = btrfs_node_blockptr(eb, slot);
7869 generation = btrfs_node_ptr_generation(eb, slot);
7871 if (slot == path->slots[wc->level])
7874 if (wc->stage == UPDATE_BACKREF &&
7875 generation <= root->root_key.offset)
7878 /* We don't lock the tree block, it's OK to be racy here */
7879 ret = btrfs_lookup_extent_info(trans, root, bytenr,
7880 wc->level - 1, 1, &refs,
7882 /* We don't care about errors in readahead. */
7887 if (wc->stage == DROP_REFERENCE) {
7891 if (wc->level == 1 &&
7892 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
7894 if (!wc->update_ref ||
7895 generation <= root->root_key.offset)
7897 btrfs_node_key_to_cpu(eb, &key, slot);
7898 ret = btrfs_comp_cpu_keys(&key,
7899 &wc->update_progress);
7903 if (wc->level == 1 &&
7904 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
7908 readahead_tree_block(root, bytenr);
7911 wc->reada_slot = slot;
7915 * TODO: Modify related function to add related node/leaf to dirty_extent_root,
7916 * for later qgroup accounting.
7918 * Current, this function does nothing.
7920 static int account_leaf_items(struct btrfs_trans_handle *trans,
7921 struct btrfs_root *root,
7922 struct extent_buffer *eb)
7924 int nr = btrfs_header_nritems(eb);
7926 struct btrfs_key key;
7927 struct btrfs_file_extent_item *fi;
7928 u64 bytenr, num_bytes;
7930 for (i = 0; i < nr; i++) {
7931 btrfs_item_key_to_cpu(eb, &key, i);
7933 if (key.type != BTRFS_EXTENT_DATA_KEY)
7936 fi = btrfs_item_ptr(eb, i, struct btrfs_file_extent_item);
7937 /* filter out non qgroup-accountable extents */
7938 extent_type = btrfs_file_extent_type(eb, fi);
7940 if (extent_type == BTRFS_FILE_EXTENT_INLINE)
7943 bytenr = btrfs_file_extent_disk_bytenr(eb, fi);
7947 num_bytes = btrfs_file_extent_disk_num_bytes(eb, fi);
7953 * Walk up the tree from the bottom, freeing leaves and any interior
7954 * nodes which have had all slots visited. If a node (leaf or
7955 * interior) is freed, the node above it will have it's slot
7956 * incremented. The root node will never be freed.
7958 * At the end of this function, we should have a path which has all
7959 * slots incremented to the next position for a search. If we need to
7960 * read a new node it will be NULL and the node above it will have the
7961 * correct slot selected for a later read.
7963 * If we increment the root nodes slot counter past the number of
7964 * elements, 1 is returned to signal completion of the search.
7966 static int adjust_slots_upwards(struct btrfs_root *root,
7967 struct btrfs_path *path, int root_level)
7971 struct extent_buffer *eb;
7973 if (root_level == 0)
7976 while (level <= root_level) {
7977 eb = path->nodes[level];
7978 nr = btrfs_header_nritems(eb);
7979 path->slots[level]++;
7980 slot = path->slots[level];
7981 if (slot >= nr || level == 0) {
7983 * Don't free the root - we will detect this
7984 * condition after our loop and return a
7985 * positive value for caller to stop walking the tree.
7987 if (level != root_level) {
7988 btrfs_tree_unlock_rw(eb, path->locks[level]);
7989 path->locks[level] = 0;
7991 free_extent_buffer(eb);
7992 path->nodes[level] = NULL;
7993 path->slots[level] = 0;
7997 * We have a valid slot to walk back down
7998 * from. Stop here so caller can process these
8007 eb = path->nodes[root_level];
8008 if (path->slots[root_level] >= btrfs_header_nritems(eb))
8015 * root_eb is the subtree root and is locked before this function is called.
8016 * TODO: Modify this function to mark all (including complete shared node)
8017 * to dirty_extent_root to allow it get accounted in qgroup.
8019 static int account_shared_subtree(struct btrfs_trans_handle *trans,
8020 struct btrfs_root *root,
8021 struct extent_buffer *root_eb,
8027 struct extent_buffer *eb = root_eb;
8028 struct btrfs_path *path = NULL;
8030 BUG_ON(root_level < 0 || root_level > BTRFS_MAX_LEVEL);
8031 BUG_ON(root_eb == NULL);
8033 if (!root->fs_info->quota_enabled)
8036 if (!extent_buffer_uptodate(root_eb)) {
8037 ret = btrfs_read_buffer(root_eb, root_gen);
8042 if (root_level == 0) {
8043 ret = account_leaf_items(trans, root, root_eb);
8047 path = btrfs_alloc_path();
8052 * Walk down the tree. Missing extent blocks are filled in as
8053 * we go. Metadata is accounted every time we read a new
8056 * When we reach a leaf, we account for file extent items in it,
8057 * walk back up the tree (adjusting slot pointers as we go)
8058 * and restart the search process.
8060 extent_buffer_get(root_eb); /* For path */
8061 path->nodes[root_level] = root_eb;
8062 path->slots[root_level] = 0;
8063 path->locks[root_level] = 0; /* so release_path doesn't try to unlock */
8066 while (level >= 0) {
8067 if (path->nodes[level] == NULL) {
8072 /* We need to get child blockptr/gen from
8073 * parent before we can read it. */
8074 eb = path->nodes[level + 1];
8075 parent_slot = path->slots[level + 1];
8076 child_bytenr = btrfs_node_blockptr(eb, parent_slot);
8077 child_gen = btrfs_node_ptr_generation(eb, parent_slot);
8079 eb = read_tree_block(root, child_bytenr, child_gen);
8083 } else if (!extent_buffer_uptodate(eb)) {
8084 free_extent_buffer(eb);
8089 path->nodes[level] = eb;
8090 path->slots[level] = 0;
8092 btrfs_tree_read_lock(eb);
8093 btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
8094 path->locks[level] = BTRFS_READ_LOCK_BLOCKING;
8098 ret = account_leaf_items(trans, root, path->nodes[level]);
8102 /* Nonzero return here means we completed our search */
8103 ret = adjust_slots_upwards(root, path, root_level);
8107 /* Restart search with new slots */
8116 btrfs_free_path(path);
8122 * helper to process tree block while walking down the tree.
8124 * when wc->stage == UPDATE_BACKREF, this function updates
8125 * back refs for pointers in the block.
8127 * NOTE: return value 1 means we should stop walking down.
8129 static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
8130 struct btrfs_root *root,
8131 struct btrfs_path *path,
8132 struct walk_control *wc, int lookup_info)
8134 int level = wc->level;
8135 struct extent_buffer *eb = path->nodes[level];
8136 u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF;
8139 if (wc->stage == UPDATE_BACKREF &&
8140 btrfs_header_owner(eb) != root->root_key.objectid)
8144 * when reference count of tree block is 1, it won't increase
8145 * again. once full backref flag is set, we never clear it.
8148 ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
8149 (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag)))) {
8150 BUG_ON(!path->locks[level]);
8151 ret = btrfs_lookup_extent_info(trans, root,
8152 eb->start, level, 1,
8155 BUG_ON(ret == -ENOMEM);
8158 BUG_ON(wc->refs[level] == 0);
8161 if (wc->stage == DROP_REFERENCE) {
8162 if (wc->refs[level] > 1)
8165 if (path->locks[level] && !wc->keep_locks) {
8166 btrfs_tree_unlock_rw(eb, path->locks[level]);
8167 path->locks[level] = 0;
8172 /* wc->stage == UPDATE_BACKREF */
8173 if (!(wc->flags[level] & flag)) {
8174 BUG_ON(!path->locks[level]);
8175 ret = btrfs_inc_ref(trans, root, eb, 1);
8176 BUG_ON(ret); /* -ENOMEM */
8177 ret = btrfs_dec_ref(trans, root, eb, 0);
8178 BUG_ON(ret); /* -ENOMEM */
8179 ret = btrfs_set_disk_extent_flags(trans, root, eb->start,
8181 btrfs_header_level(eb), 0);
8182 BUG_ON(ret); /* -ENOMEM */
8183 wc->flags[level] |= flag;
8187 * the block is shared by multiple trees, so it's not good to
8188 * keep the tree lock
8190 if (path->locks[level] && level > 0) {
8191 btrfs_tree_unlock_rw(eb, path->locks[level]);
8192 path->locks[level] = 0;
8198 * helper to process tree block pointer.
8200 * when wc->stage == DROP_REFERENCE, this function checks
8201 * reference count of the block pointed to. if the block
8202 * is shared and we need update back refs for the subtree
8203 * rooted at the block, this function changes wc->stage to
8204 * UPDATE_BACKREF. if the block is shared and there is no
8205 * need to update back, this function drops the reference
8208 * NOTE: return value 1 means we should stop walking down.
8210 static noinline int do_walk_down(struct btrfs_trans_handle *trans,
8211 struct btrfs_root *root,
8212 struct btrfs_path *path,
8213 struct walk_control *wc, int *lookup_info)
8219 struct btrfs_key key;
8220 struct extent_buffer *next;
8221 int level = wc->level;
8224 bool need_account = false;
8226 generation = btrfs_node_ptr_generation(path->nodes[level],
8227 path->slots[level]);
8229 * if the lower level block was created before the snapshot
8230 * was created, we know there is no need to update back refs
8233 if (wc->stage == UPDATE_BACKREF &&
8234 generation <= root->root_key.offset) {
8239 bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]);
8240 blocksize = root->nodesize;
8242 next = btrfs_find_tree_block(root->fs_info, bytenr);
8244 next = btrfs_find_create_tree_block(root, bytenr);
8247 btrfs_set_buffer_lockdep_class(root->root_key.objectid, next,
8251 btrfs_tree_lock(next);
8252 btrfs_set_lock_blocking(next);
8254 ret = btrfs_lookup_extent_info(trans, root, bytenr, level - 1, 1,
8255 &wc->refs[level - 1],
8256 &wc->flags[level - 1]);
8258 btrfs_tree_unlock(next);
8262 if (unlikely(wc->refs[level - 1] == 0)) {
8263 btrfs_err(root->fs_info, "Missing references.");
8268 if (wc->stage == DROP_REFERENCE) {
8269 if (wc->refs[level - 1] > 1) {
8270 need_account = true;
8272 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
8275 if (!wc->update_ref ||
8276 generation <= root->root_key.offset)
8279 btrfs_node_key_to_cpu(path->nodes[level], &key,
8280 path->slots[level]);
8281 ret = btrfs_comp_cpu_keys(&key, &wc->update_progress);
8285 wc->stage = UPDATE_BACKREF;
8286 wc->shared_level = level - 1;
8290 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
8294 if (!btrfs_buffer_uptodate(next, generation, 0)) {
8295 btrfs_tree_unlock(next);
8296 free_extent_buffer(next);
8302 if (reada && level == 1)
8303 reada_walk_down(trans, root, wc, path);
8304 next = read_tree_block(root, bytenr, generation);
8306 return PTR_ERR(next);
8307 } else if (!extent_buffer_uptodate(next)) {
8308 free_extent_buffer(next);
8311 btrfs_tree_lock(next);
8312 btrfs_set_lock_blocking(next);
8316 BUG_ON(level != btrfs_header_level(next));
8317 path->nodes[level] = next;
8318 path->slots[level] = 0;
8319 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
8325 wc->refs[level - 1] = 0;
8326 wc->flags[level - 1] = 0;
8327 if (wc->stage == DROP_REFERENCE) {
8328 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
8329 parent = path->nodes[level]->start;
8331 BUG_ON(root->root_key.objectid !=
8332 btrfs_header_owner(path->nodes[level]));
8337 ret = account_shared_subtree(trans, root, next,
8338 generation, level - 1);
8340 btrfs_err_rl(root->fs_info,
8342 "%d accounting shared subtree. Quota "
8343 "is out of sync, rescan required.",
8347 ret = btrfs_free_extent(trans, root, bytenr, blocksize, parent,
8348 root->root_key.objectid, level - 1, 0, 0);
8349 BUG_ON(ret); /* -ENOMEM */
8351 btrfs_tree_unlock(next);
8352 free_extent_buffer(next);
8358 * helper to process tree block while walking up the tree.
8360 * when wc->stage == DROP_REFERENCE, this function drops
8361 * reference count on the block.
8363 * when wc->stage == UPDATE_BACKREF, this function changes
8364 * wc->stage back to DROP_REFERENCE if we changed wc->stage
8365 * to UPDATE_BACKREF previously while processing the block.
8367 * NOTE: return value 1 means we should stop walking up.
8369 static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
8370 struct btrfs_root *root,
8371 struct btrfs_path *path,
8372 struct walk_control *wc)
8375 int level = wc->level;
8376 struct extent_buffer *eb = path->nodes[level];
8379 if (wc->stage == UPDATE_BACKREF) {
8380 BUG_ON(wc->shared_level < level);
8381 if (level < wc->shared_level)
8384 ret = find_next_key(path, level + 1, &wc->update_progress);
8388 wc->stage = DROP_REFERENCE;
8389 wc->shared_level = -1;
8390 path->slots[level] = 0;
8393 * check reference count again if the block isn't locked.
8394 * we should start walking down the tree again if reference
8397 if (!path->locks[level]) {
8399 btrfs_tree_lock(eb);
8400 btrfs_set_lock_blocking(eb);
8401 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
8403 ret = btrfs_lookup_extent_info(trans, root,
8404 eb->start, level, 1,
8408 btrfs_tree_unlock_rw(eb, path->locks[level]);
8409 path->locks[level] = 0;
8412 BUG_ON(wc->refs[level] == 0);
8413 if (wc->refs[level] == 1) {
8414 btrfs_tree_unlock_rw(eb, path->locks[level]);
8415 path->locks[level] = 0;
8421 /* wc->stage == DROP_REFERENCE */
8422 BUG_ON(wc->refs[level] > 1 && !path->locks[level]);
8424 if (wc->refs[level] == 1) {
8426 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
8427 ret = btrfs_dec_ref(trans, root, eb, 1);
8429 ret = btrfs_dec_ref(trans, root, eb, 0);
8430 BUG_ON(ret); /* -ENOMEM */
8431 ret = account_leaf_items(trans, root, eb);
8433 btrfs_err_rl(root->fs_info,
8435 "%d accounting leaf items. Quota "
8436 "is out of sync, rescan required.",
8440 /* make block locked assertion in clean_tree_block happy */
8441 if (!path->locks[level] &&
8442 btrfs_header_generation(eb) == trans->transid) {
8443 btrfs_tree_lock(eb);
8444 btrfs_set_lock_blocking(eb);
8445 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
8447 clean_tree_block(trans, root->fs_info, eb);
8450 if (eb == root->node) {
8451 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
8454 BUG_ON(root->root_key.objectid !=
8455 btrfs_header_owner(eb));
8457 if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
8458 parent = path->nodes[level + 1]->start;
8460 BUG_ON(root->root_key.objectid !=
8461 btrfs_header_owner(path->nodes[level + 1]));
8464 btrfs_free_tree_block(trans, root, eb, parent, wc->refs[level] == 1);
8466 wc->refs[level] = 0;
8467 wc->flags[level] = 0;
8471 static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
8472 struct btrfs_root *root,
8473 struct btrfs_path *path,
8474 struct walk_control *wc)
8476 int level = wc->level;
8477 int lookup_info = 1;
8480 while (level >= 0) {
8481 ret = walk_down_proc(trans, root, path, wc, lookup_info);
8488 if (path->slots[level] >=
8489 btrfs_header_nritems(path->nodes[level]))
8492 ret = do_walk_down(trans, root, path, wc, &lookup_info);
8494 path->slots[level]++;
8503 static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
8504 struct btrfs_root *root,
8505 struct btrfs_path *path,
8506 struct walk_control *wc, int max_level)
8508 int level = wc->level;
8511 path->slots[level] = btrfs_header_nritems(path->nodes[level]);
8512 while (level < max_level && path->nodes[level]) {
8514 if (path->slots[level] + 1 <
8515 btrfs_header_nritems(path->nodes[level])) {
8516 path->slots[level]++;
8519 ret = walk_up_proc(trans, root, path, wc);
8523 if (path->locks[level]) {
8524 btrfs_tree_unlock_rw(path->nodes[level],
8525 path->locks[level]);
8526 path->locks[level] = 0;
8528 free_extent_buffer(path->nodes[level]);
8529 path->nodes[level] = NULL;
8537 * drop a subvolume tree.
8539 * this function traverses the tree freeing any blocks that only
8540 * referenced by the tree.
8542 * when a shared tree block is found. this function decreases its
8543 * reference count by one. if update_ref is true, this function
8544 * also make sure backrefs for the shared block and all lower level
8545 * blocks are properly updated.
8547 * If called with for_reloc == 0, may exit early with -EAGAIN
8549 int btrfs_drop_snapshot(struct btrfs_root *root,
8550 struct btrfs_block_rsv *block_rsv, int update_ref,
8553 struct btrfs_path *path;
8554 struct btrfs_trans_handle *trans;
8555 struct btrfs_root *tree_root = root->fs_info->tree_root;
8556 struct btrfs_root_item *root_item = &root->root_item;
8557 struct walk_control *wc;
8558 struct btrfs_key key;
8562 bool root_dropped = false;
8564 btrfs_debug(root->fs_info, "Drop subvolume %llu", root->objectid);
8566 path = btrfs_alloc_path();
8572 wc = kzalloc(sizeof(*wc), GFP_NOFS);
8574 btrfs_free_path(path);
8579 trans = btrfs_start_transaction(tree_root, 0);
8580 if (IS_ERR(trans)) {
8581 err = PTR_ERR(trans);
8586 trans->block_rsv = block_rsv;
8588 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
8589 level = btrfs_header_level(root->node);
8590 path->nodes[level] = btrfs_lock_root_node(root);
8591 btrfs_set_lock_blocking(path->nodes[level]);
8592 path->slots[level] = 0;
8593 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
8594 memset(&wc->update_progress, 0,
8595 sizeof(wc->update_progress));
8597 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
8598 memcpy(&wc->update_progress, &key,
8599 sizeof(wc->update_progress));
8601 level = root_item->drop_level;
8603 path->lowest_level = level;
8604 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
8605 path->lowest_level = 0;
8613 * unlock our path, this is safe because only this
8614 * function is allowed to delete this snapshot
8616 btrfs_unlock_up_safe(path, 0);
8618 level = btrfs_header_level(root->node);
8620 btrfs_tree_lock(path->nodes[level]);
8621 btrfs_set_lock_blocking(path->nodes[level]);
8622 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
8624 ret = btrfs_lookup_extent_info(trans, root,
8625 path->nodes[level]->start,
8626 level, 1, &wc->refs[level],
8632 BUG_ON(wc->refs[level] == 0);
8634 if (level == root_item->drop_level)
8637 btrfs_tree_unlock(path->nodes[level]);
8638 path->locks[level] = 0;
8639 WARN_ON(wc->refs[level] != 1);
8645 wc->shared_level = -1;
8646 wc->stage = DROP_REFERENCE;
8647 wc->update_ref = update_ref;
8649 wc->for_reloc = for_reloc;
8650 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
8654 ret = walk_down_tree(trans, root, path, wc);
8660 ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL);
8667 BUG_ON(wc->stage != DROP_REFERENCE);
8671 if (wc->stage == DROP_REFERENCE) {
8673 btrfs_node_key(path->nodes[level],
8674 &root_item->drop_progress,
8675 path->slots[level]);
8676 root_item->drop_level = level;
8679 BUG_ON(wc->level == 0);
8680 if (btrfs_should_end_transaction(trans, tree_root) ||
8681 (!for_reloc && btrfs_need_cleaner_sleep(root))) {
8682 ret = btrfs_update_root(trans, tree_root,
8686 btrfs_abort_transaction(trans, tree_root, ret);
8691 btrfs_end_transaction_throttle(trans, tree_root);
8692 if (!for_reloc && btrfs_need_cleaner_sleep(root)) {
8693 pr_debug("BTRFS: drop snapshot early exit\n");
8698 trans = btrfs_start_transaction(tree_root, 0);
8699 if (IS_ERR(trans)) {
8700 err = PTR_ERR(trans);
8704 trans->block_rsv = block_rsv;
8707 btrfs_release_path(path);
8711 ret = btrfs_del_root(trans, tree_root, &root->root_key);
8713 btrfs_abort_transaction(trans, tree_root, ret);
8717 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
8718 ret = btrfs_find_root(tree_root, &root->root_key, path,
8721 btrfs_abort_transaction(trans, tree_root, ret);
8724 } else if (ret > 0) {
8725 /* if we fail to delete the orphan item this time
8726 * around, it'll get picked up the next time.
8728 * The most common failure here is just -ENOENT.
8730 btrfs_del_orphan_item(trans, tree_root,
8731 root->root_key.objectid);
8735 if (test_bit(BTRFS_ROOT_IN_RADIX, &root->state)) {
8736 btrfs_add_dropped_root(trans, root);
8738 free_extent_buffer(root->node);
8739 free_extent_buffer(root->commit_root);
8740 btrfs_put_fs_root(root);
8742 root_dropped = true;
8744 btrfs_end_transaction_throttle(trans, tree_root);
8747 btrfs_free_path(path);
8750 * So if we need to stop dropping the snapshot for whatever reason we
8751 * need to make sure to add it back to the dead root list so that we
8752 * keep trying to do the work later. This also cleans up roots if we
8753 * don't have it in the radix (like when we recover after a power fail
8754 * or unmount) so we don't leak memory.
8756 if (!for_reloc && root_dropped == false)
8757 btrfs_add_dead_root(root);
8758 if (err && err != -EAGAIN)
8759 btrfs_std_error(root->fs_info, err, NULL);
8764 * drop subtree rooted at tree block 'node'.
8766 * NOTE: this function will unlock and release tree block 'node'
8767 * only used by relocation code
8769 int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
8770 struct btrfs_root *root,
8771 struct extent_buffer *node,
8772 struct extent_buffer *parent)
8774 struct btrfs_path *path;
8775 struct walk_control *wc;
8781 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
8783 path = btrfs_alloc_path();
8787 wc = kzalloc(sizeof(*wc), GFP_NOFS);
8789 btrfs_free_path(path);
8793 btrfs_assert_tree_locked(parent);
8794 parent_level = btrfs_header_level(parent);
8795 extent_buffer_get(parent);
8796 path->nodes[parent_level] = parent;
8797 path->slots[parent_level] = btrfs_header_nritems(parent);
8799 btrfs_assert_tree_locked(node);
8800 level = btrfs_header_level(node);
8801 path->nodes[level] = node;
8802 path->slots[level] = 0;
8803 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
8805 wc->refs[parent_level] = 1;
8806 wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF;
8808 wc->shared_level = -1;
8809 wc->stage = DROP_REFERENCE;
8813 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
8816 wret = walk_down_tree(trans, root, path, wc);
8822 wret = walk_up_tree(trans, root, path, wc, parent_level);
8830 btrfs_free_path(path);
8834 static u64 update_block_group_flags(struct btrfs_root *root, u64 flags)
8840 * if restripe for this chunk_type is on pick target profile and
8841 * return, otherwise do the usual balance
8843 stripped = get_restripe_target(root->fs_info, flags);
8845 return extended_to_chunk(stripped);
8847 num_devices = root->fs_info->fs_devices->rw_devices;
8849 stripped = BTRFS_BLOCK_GROUP_RAID0 |
8850 BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6 |
8851 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
8853 if (num_devices == 1) {
8854 stripped |= BTRFS_BLOCK_GROUP_DUP;
8855 stripped = flags & ~stripped;
8857 /* turn raid0 into single device chunks */
8858 if (flags & BTRFS_BLOCK_GROUP_RAID0)
8861 /* turn mirroring into duplication */
8862 if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
8863 BTRFS_BLOCK_GROUP_RAID10))
8864 return stripped | BTRFS_BLOCK_GROUP_DUP;
8866 /* they already had raid on here, just return */
8867 if (flags & stripped)
8870 stripped |= BTRFS_BLOCK_GROUP_DUP;
8871 stripped = flags & ~stripped;
8873 /* switch duplicated blocks with raid1 */
8874 if (flags & BTRFS_BLOCK_GROUP_DUP)
8875 return stripped | BTRFS_BLOCK_GROUP_RAID1;
8877 /* this is drive concat, leave it alone */
8883 static int inc_block_group_ro(struct btrfs_block_group_cache *cache, int force)
8885 struct btrfs_space_info *sinfo = cache->space_info;
8887 u64 min_allocable_bytes;
8891 * We need some metadata space and system metadata space for
8892 * allocating chunks in some corner cases until we force to set
8893 * it to be readonly.
8896 (BTRFS_BLOCK_GROUP_SYSTEM | BTRFS_BLOCK_GROUP_METADATA)) &&
8898 min_allocable_bytes = 1 * 1024 * 1024;
8900 min_allocable_bytes = 0;
8902 spin_lock(&sinfo->lock);
8903 spin_lock(&cache->lock);
8911 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
8912 cache->bytes_super - btrfs_block_group_used(&cache->item);
8914 if (sinfo->bytes_used + sinfo->bytes_reserved + sinfo->bytes_pinned +
8915 sinfo->bytes_may_use + sinfo->bytes_readonly + num_bytes +
8916 min_allocable_bytes <= sinfo->total_bytes) {
8917 sinfo->bytes_readonly += num_bytes;
8919 list_add_tail(&cache->ro_list, &sinfo->ro_bgs);
8923 spin_unlock(&cache->lock);
8924 spin_unlock(&sinfo->lock);
8928 int btrfs_inc_block_group_ro(struct btrfs_root *root,
8929 struct btrfs_block_group_cache *cache)
8932 struct btrfs_trans_handle *trans;
8937 trans = btrfs_join_transaction(root);
8939 return PTR_ERR(trans);
8942 * we're not allowed to set block groups readonly after the dirty
8943 * block groups cache has started writing. If it already started,
8944 * back off and let this transaction commit
8946 mutex_lock(&root->fs_info->ro_block_group_mutex);
8947 if (trans->transaction->dirty_bg_run) {
8948 u64 transid = trans->transid;
8950 mutex_unlock(&root->fs_info->ro_block_group_mutex);
8951 btrfs_end_transaction(trans, root);
8953 ret = btrfs_wait_for_commit(root, transid);
8960 * if we are changing raid levels, try to allocate a corresponding
8961 * block group with the new raid level.
8963 alloc_flags = update_block_group_flags(root, cache->flags);
8964 if (alloc_flags != cache->flags) {
8965 ret = do_chunk_alloc(trans, root, alloc_flags,
8968 * ENOSPC is allowed here, we may have enough space
8969 * already allocated at the new raid level to
8978 ret = inc_block_group_ro(cache, 0);
8981 alloc_flags = get_alloc_profile(root, cache->space_info->flags);
8982 ret = do_chunk_alloc(trans, root, alloc_flags,
8986 ret = inc_block_group_ro(cache, 0);
8988 if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM) {
8989 alloc_flags = update_block_group_flags(root, cache->flags);
8990 lock_chunks(root->fs_info->chunk_root);
8991 check_system_chunk(trans, root, alloc_flags);
8992 unlock_chunks(root->fs_info->chunk_root);
8994 mutex_unlock(&root->fs_info->ro_block_group_mutex);
8996 btrfs_end_transaction(trans, root);
9000 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans,
9001 struct btrfs_root *root, u64 type)
9003 u64 alloc_flags = get_alloc_profile(root, type);
9004 return do_chunk_alloc(trans, root, alloc_flags,
9009 * helper to account the unused space of all the readonly block group in the
9010 * space_info. takes mirrors into account.
9012 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo)
9014 struct btrfs_block_group_cache *block_group;
9018 /* It's df, we don't care if it's racey */
9019 if (list_empty(&sinfo->ro_bgs))
9022 spin_lock(&sinfo->lock);
9023 list_for_each_entry(block_group, &sinfo->ro_bgs, ro_list) {
9024 spin_lock(&block_group->lock);
9026 if (!block_group->ro) {
9027 spin_unlock(&block_group->lock);
9031 if (block_group->flags & (BTRFS_BLOCK_GROUP_RAID1 |
9032 BTRFS_BLOCK_GROUP_RAID10 |
9033 BTRFS_BLOCK_GROUP_DUP))
9038 free_bytes += (block_group->key.offset -
9039 btrfs_block_group_used(&block_group->item)) *
9042 spin_unlock(&block_group->lock);
9044 spin_unlock(&sinfo->lock);
9049 void btrfs_dec_block_group_ro(struct btrfs_root *root,
9050 struct btrfs_block_group_cache *cache)
9052 struct btrfs_space_info *sinfo = cache->space_info;
9057 spin_lock(&sinfo->lock);
9058 spin_lock(&cache->lock);
9060 num_bytes = cache->key.offset - cache->reserved -
9061 cache->pinned - cache->bytes_super -
9062 btrfs_block_group_used(&cache->item);
9063 sinfo->bytes_readonly -= num_bytes;
9064 list_del_init(&cache->ro_list);
9066 spin_unlock(&cache->lock);
9067 spin_unlock(&sinfo->lock);
9071 * checks to see if its even possible to relocate this block group.
9073 * @return - -1 if it's not a good idea to relocate this block group, 0 if its
9074 * ok to go ahead and try.
9076 int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
9078 struct btrfs_block_group_cache *block_group;
9079 struct btrfs_space_info *space_info;
9080 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
9081 struct btrfs_device *device;
9082 struct btrfs_trans_handle *trans;
9091 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
9093 /* odd, couldn't find the block group, leave it alone */
9097 min_free = btrfs_block_group_used(&block_group->item);
9099 /* no bytes used, we're good */
9103 space_info = block_group->space_info;
9104 spin_lock(&space_info->lock);
9106 full = space_info->full;
9109 * if this is the last block group we have in this space, we can't
9110 * relocate it unless we're able to allocate a new chunk below.
9112 * Otherwise, we need to make sure we have room in the space to handle
9113 * all of the extents from this block group. If we can, we're good
9115 if ((space_info->total_bytes != block_group->key.offset) &&
9116 (space_info->bytes_used + space_info->bytes_reserved +
9117 space_info->bytes_pinned + space_info->bytes_readonly +
9118 min_free < space_info->total_bytes)) {
9119 spin_unlock(&space_info->lock);
9122 spin_unlock(&space_info->lock);
9125 * ok we don't have enough space, but maybe we have free space on our
9126 * devices to allocate new chunks for relocation, so loop through our
9127 * alloc devices and guess if we have enough space. if this block
9128 * group is going to be restriped, run checks against the target
9129 * profile instead of the current one.
9141 target = get_restripe_target(root->fs_info, block_group->flags);
9143 index = __get_raid_index(extended_to_chunk(target));
9146 * this is just a balance, so if we were marked as full
9147 * we know there is no space for a new chunk
9152 index = get_block_group_index(block_group);
9155 if (index == BTRFS_RAID_RAID10) {
9159 } else if (index == BTRFS_RAID_RAID1) {
9161 } else if (index == BTRFS_RAID_DUP) {
9164 } else if (index == BTRFS_RAID_RAID0) {
9165 dev_min = fs_devices->rw_devices;
9166 min_free = div64_u64(min_free, dev_min);
9169 /* We need to do this so that we can look at pending chunks */
9170 trans = btrfs_join_transaction(root);
9171 if (IS_ERR(trans)) {
9172 ret = PTR_ERR(trans);
9176 mutex_lock(&root->fs_info->chunk_mutex);
9177 list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
9181 * check to make sure we can actually find a chunk with enough
9182 * space to fit our block group in.
9184 if (device->total_bytes > device->bytes_used + min_free &&
9185 !device->is_tgtdev_for_dev_replace) {
9186 ret = find_free_dev_extent(trans, device, min_free,
9191 if (dev_nr >= dev_min)
9197 mutex_unlock(&root->fs_info->chunk_mutex);
9198 btrfs_end_transaction(trans, root);
9200 btrfs_put_block_group(block_group);
9204 static int find_first_block_group(struct btrfs_root *root,
9205 struct btrfs_path *path, struct btrfs_key *key)
9208 struct btrfs_key found_key;
9209 struct extent_buffer *leaf;
9212 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
9217 slot = path->slots[0];
9218 leaf = path->nodes[0];
9219 if (slot >= btrfs_header_nritems(leaf)) {
9220 ret = btrfs_next_leaf(root, path);
9227 btrfs_item_key_to_cpu(leaf, &found_key, slot);
9229 if (found_key.objectid >= key->objectid &&
9230 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
9240 void btrfs_put_block_group_cache(struct btrfs_fs_info *info)
9242 struct btrfs_block_group_cache *block_group;
9246 struct inode *inode;
9248 block_group = btrfs_lookup_first_block_group(info, last);
9249 while (block_group) {
9250 spin_lock(&block_group->lock);
9251 if (block_group->iref)
9253 spin_unlock(&block_group->lock);
9254 block_group = next_block_group(info->tree_root,
9264 inode = block_group->inode;
9265 block_group->iref = 0;
9266 block_group->inode = NULL;
9267 spin_unlock(&block_group->lock);
9269 last = block_group->key.objectid + block_group->key.offset;
9270 btrfs_put_block_group(block_group);
9274 int btrfs_free_block_groups(struct btrfs_fs_info *info)
9276 struct btrfs_block_group_cache *block_group;
9277 struct btrfs_space_info *space_info;
9278 struct btrfs_caching_control *caching_ctl;
9281 down_write(&info->commit_root_sem);
9282 while (!list_empty(&info->caching_block_groups)) {
9283 caching_ctl = list_entry(info->caching_block_groups.next,
9284 struct btrfs_caching_control, list);
9285 list_del(&caching_ctl->list);
9286 put_caching_control(caching_ctl);
9288 up_write(&info->commit_root_sem);
9290 spin_lock(&info->unused_bgs_lock);
9291 while (!list_empty(&info->unused_bgs)) {
9292 block_group = list_first_entry(&info->unused_bgs,
9293 struct btrfs_block_group_cache,
9295 list_del_init(&block_group->bg_list);
9296 btrfs_put_block_group(block_group);
9298 spin_unlock(&info->unused_bgs_lock);
9300 spin_lock(&info->block_group_cache_lock);
9301 while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
9302 block_group = rb_entry(n, struct btrfs_block_group_cache,
9304 rb_erase(&block_group->cache_node,
9305 &info->block_group_cache_tree);
9306 RB_CLEAR_NODE(&block_group->cache_node);
9307 spin_unlock(&info->block_group_cache_lock);
9309 down_write(&block_group->space_info->groups_sem);
9310 list_del(&block_group->list);
9311 up_write(&block_group->space_info->groups_sem);
9313 if (block_group->cached == BTRFS_CACHE_STARTED)
9314 wait_block_group_cache_done(block_group);
9317 * We haven't cached this block group, which means we could
9318 * possibly have excluded extents on this block group.
9320 if (block_group->cached == BTRFS_CACHE_NO ||
9321 block_group->cached == BTRFS_CACHE_ERROR)
9322 free_excluded_extents(info->extent_root, block_group);
9324 btrfs_remove_free_space_cache(block_group);
9325 btrfs_put_block_group(block_group);
9327 spin_lock(&info->block_group_cache_lock);
9329 spin_unlock(&info->block_group_cache_lock);
9331 /* now that all the block groups are freed, go through and
9332 * free all the space_info structs. This is only called during
9333 * the final stages of unmount, and so we know nobody is
9334 * using them. We call synchronize_rcu() once before we start,
9335 * just to be on the safe side.
9339 release_global_block_rsv(info);
9341 while (!list_empty(&info->space_info)) {
9344 space_info = list_entry(info->space_info.next,
9345 struct btrfs_space_info,
9347 if (btrfs_test_opt(info->tree_root, ENOSPC_DEBUG)) {
9348 if (WARN_ON(space_info->bytes_pinned > 0 ||
9349 space_info->bytes_reserved > 0 ||
9350 space_info->bytes_may_use > 0)) {
9351 dump_space_info(space_info, 0, 0);
9354 list_del(&space_info->list);
9355 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
9356 struct kobject *kobj;
9357 kobj = space_info->block_group_kobjs[i];
9358 space_info->block_group_kobjs[i] = NULL;
9364 kobject_del(&space_info->kobj);
9365 kobject_put(&space_info->kobj);
9370 static void __link_block_group(struct btrfs_space_info *space_info,
9371 struct btrfs_block_group_cache *cache)
9373 int index = get_block_group_index(cache);
9376 down_write(&space_info->groups_sem);
9377 if (list_empty(&space_info->block_groups[index]))
9379 list_add_tail(&cache->list, &space_info->block_groups[index]);
9380 up_write(&space_info->groups_sem);
9383 struct raid_kobject *rkobj;
9386 rkobj = kzalloc(sizeof(*rkobj), GFP_NOFS);
9389 rkobj->raid_type = index;
9390 kobject_init(&rkobj->kobj, &btrfs_raid_ktype);
9391 ret = kobject_add(&rkobj->kobj, &space_info->kobj,
9392 "%s", get_raid_name(index));
9394 kobject_put(&rkobj->kobj);
9397 space_info->block_group_kobjs[index] = &rkobj->kobj;
9402 pr_warn("BTRFS: failed to add kobject for block cache. ignoring.\n");
9405 static struct btrfs_block_group_cache *
9406 btrfs_create_block_group_cache(struct btrfs_root *root, u64 start, u64 size)
9408 struct btrfs_block_group_cache *cache;
9410 cache = kzalloc(sizeof(*cache), GFP_NOFS);
9414 cache->free_space_ctl = kzalloc(sizeof(*cache->free_space_ctl),
9416 if (!cache->free_space_ctl) {
9421 cache->key.objectid = start;
9422 cache->key.offset = size;
9423 cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
9425 cache->sectorsize = root->sectorsize;
9426 cache->fs_info = root->fs_info;
9427 cache->full_stripe_len = btrfs_full_stripe_len(root,
9428 &root->fs_info->mapping_tree,
9430 atomic_set(&cache->count, 1);
9431 spin_lock_init(&cache->lock);
9432 init_rwsem(&cache->data_rwsem);
9433 INIT_LIST_HEAD(&cache->list);
9434 INIT_LIST_HEAD(&cache->cluster_list);
9435 INIT_LIST_HEAD(&cache->bg_list);
9436 INIT_LIST_HEAD(&cache->ro_list);
9437 INIT_LIST_HEAD(&cache->dirty_list);
9438 INIT_LIST_HEAD(&cache->io_list);
9439 btrfs_init_free_space_ctl(cache);
9440 atomic_set(&cache->trimming, 0);
9445 int btrfs_read_block_groups(struct btrfs_root *root)
9447 struct btrfs_path *path;
9449 struct btrfs_block_group_cache *cache;
9450 struct btrfs_fs_info *info = root->fs_info;
9451 struct btrfs_space_info *space_info;
9452 struct btrfs_key key;
9453 struct btrfs_key found_key;
9454 struct extent_buffer *leaf;
9458 root = info->extent_root;
9461 key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
9462 path = btrfs_alloc_path();
9467 cache_gen = btrfs_super_cache_generation(root->fs_info->super_copy);
9468 if (btrfs_test_opt(root, SPACE_CACHE) &&
9469 btrfs_super_generation(root->fs_info->super_copy) != cache_gen)
9471 if (btrfs_test_opt(root, CLEAR_CACHE))
9475 ret = find_first_block_group(root, path, &key);
9481 leaf = path->nodes[0];
9482 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
9484 cache = btrfs_create_block_group_cache(root, found_key.objectid,
9493 * When we mount with old space cache, we need to
9494 * set BTRFS_DC_CLEAR and set dirty flag.
9496 * a) Setting 'BTRFS_DC_CLEAR' makes sure that we
9497 * truncate the old free space cache inode and
9499 * b) Setting 'dirty flag' makes sure that we flush
9500 * the new space cache info onto disk.
9502 if (btrfs_test_opt(root, SPACE_CACHE))
9503 cache->disk_cache_state = BTRFS_DC_CLEAR;
9506 read_extent_buffer(leaf, &cache->item,
9507 btrfs_item_ptr_offset(leaf, path->slots[0]),
9508 sizeof(cache->item));
9509 cache->flags = btrfs_block_group_flags(&cache->item);
9511 key.objectid = found_key.objectid + found_key.offset;
9512 btrfs_release_path(path);
9515 * We need to exclude the super stripes now so that the space
9516 * info has super bytes accounted for, otherwise we'll think
9517 * we have more space than we actually do.
9519 ret = exclude_super_stripes(root, cache);
9522 * We may have excluded something, so call this just in
9525 free_excluded_extents(root, cache);
9526 btrfs_put_block_group(cache);
9531 * check for two cases, either we are full, and therefore
9532 * don't need to bother with the caching work since we won't
9533 * find any space, or we are empty, and we can just add all
9534 * the space in and be done with it. This saves us _alot_ of
9535 * time, particularly in the full case.
9537 if (found_key.offset == btrfs_block_group_used(&cache->item)) {
9538 cache->last_byte_to_unpin = (u64)-1;
9539 cache->cached = BTRFS_CACHE_FINISHED;
9540 free_excluded_extents(root, cache);
9541 } else if (btrfs_block_group_used(&cache->item) == 0) {
9542 cache->last_byte_to_unpin = (u64)-1;
9543 cache->cached = BTRFS_CACHE_FINISHED;
9544 add_new_free_space(cache, root->fs_info,
9546 found_key.objectid +
9548 free_excluded_extents(root, cache);
9551 ret = btrfs_add_block_group_cache(root->fs_info, cache);
9553 btrfs_remove_free_space_cache(cache);
9554 btrfs_put_block_group(cache);
9558 ret = update_space_info(info, cache->flags, found_key.offset,
9559 btrfs_block_group_used(&cache->item),
9562 btrfs_remove_free_space_cache(cache);
9563 spin_lock(&info->block_group_cache_lock);
9564 rb_erase(&cache->cache_node,
9565 &info->block_group_cache_tree);
9566 RB_CLEAR_NODE(&cache->cache_node);
9567 spin_unlock(&info->block_group_cache_lock);
9568 btrfs_put_block_group(cache);
9572 cache->space_info = space_info;
9573 spin_lock(&cache->space_info->lock);
9574 cache->space_info->bytes_readonly += cache->bytes_super;
9575 spin_unlock(&cache->space_info->lock);
9577 __link_block_group(space_info, cache);
9579 set_avail_alloc_bits(root->fs_info, cache->flags);
9580 if (btrfs_chunk_readonly(root, cache->key.objectid)) {
9581 inc_block_group_ro(cache, 1);
9582 } else if (btrfs_block_group_used(&cache->item) == 0) {
9583 spin_lock(&info->unused_bgs_lock);
9584 /* Should always be true but just in case. */
9585 if (list_empty(&cache->bg_list)) {
9586 btrfs_get_block_group(cache);
9587 list_add_tail(&cache->bg_list,
9590 spin_unlock(&info->unused_bgs_lock);
9594 list_for_each_entry_rcu(space_info, &root->fs_info->space_info, list) {
9595 if (!(get_alloc_profile(root, space_info->flags) &
9596 (BTRFS_BLOCK_GROUP_RAID10 |
9597 BTRFS_BLOCK_GROUP_RAID1 |
9598 BTRFS_BLOCK_GROUP_RAID5 |
9599 BTRFS_BLOCK_GROUP_RAID6 |
9600 BTRFS_BLOCK_GROUP_DUP)))
9603 * avoid allocating from un-mirrored block group if there are
9604 * mirrored block groups.
9606 list_for_each_entry(cache,
9607 &space_info->block_groups[BTRFS_RAID_RAID0],
9609 inc_block_group_ro(cache, 1);
9610 list_for_each_entry(cache,
9611 &space_info->block_groups[BTRFS_RAID_SINGLE],
9613 inc_block_group_ro(cache, 1);
9616 init_global_block_rsv(info);
9619 btrfs_free_path(path);
9623 void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans,
9624 struct btrfs_root *root)
9626 struct btrfs_block_group_cache *block_group, *tmp;
9627 struct btrfs_root *extent_root = root->fs_info->extent_root;
9628 struct btrfs_block_group_item item;
9629 struct btrfs_key key;
9631 bool can_flush_pending_bgs = trans->can_flush_pending_bgs;
9633 trans->can_flush_pending_bgs = false;
9634 list_for_each_entry_safe(block_group, tmp, &trans->new_bgs, bg_list) {
9638 spin_lock(&block_group->lock);
9639 memcpy(&item, &block_group->item, sizeof(item));
9640 memcpy(&key, &block_group->key, sizeof(key));
9641 spin_unlock(&block_group->lock);
9643 ret = btrfs_insert_item(trans, extent_root, &key, &item,
9646 btrfs_abort_transaction(trans, extent_root, ret);
9647 ret = btrfs_finish_chunk_alloc(trans, extent_root,
9648 key.objectid, key.offset);
9650 btrfs_abort_transaction(trans, extent_root, ret);
9652 list_del_init(&block_group->bg_list);
9654 trans->can_flush_pending_bgs = can_flush_pending_bgs;
9657 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
9658 struct btrfs_root *root, u64 bytes_used,
9659 u64 type, u64 chunk_objectid, u64 chunk_offset,
9663 struct btrfs_root *extent_root;
9664 struct btrfs_block_group_cache *cache;
9666 extent_root = root->fs_info->extent_root;
9668 btrfs_set_log_full_commit(root->fs_info, trans);
9670 cache = btrfs_create_block_group_cache(root, chunk_offset, size);
9674 btrfs_set_block_group_used(&cache->item, bytes_used);
9675 btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
9676 btrfs_set_block_group_flags(&cache->item, type);
9678 cache->flags = type;
9679 cache->last_byte_to_unpin = (u64)-1;
9680 cache->cached = BTRFS_CACHE_FINISHED;
9681 ret = exclude_super_stripes(root, cache);
9684 * We may have excluded something, so call this just in
9687 free_excluded_extents(root, cache);
9688 btrfs_put_block_group(cache);
9692 add_new_free_space(cache, root->fs_info, chunk_offset,
9693 chunk_offset + size);
9695 free_excluded_extents(root, cache);
9698 * Call to ensure the corresponding space_info object is created and
9699 * assigned to our block group, but don't update its counters just yet.
9700 * We want our bg to be added to the rbtree with its ->space_info set.
9702 ret = update_space_info(root->fs_info, cache->flags, 0, 0,
9703 &cache->space_info);
9705 btrfs_remove_free_space_cache(cache);
9706 btrfs_put_block_group(cache);
9710 ret = btrfs_add_block_group_cache(root->fs_info, cache);
9712 btrfs_remove_free_space_cache(cache);
9713 btrfs_put_block_group(cache);
9718 * Now that our block group has its ->space_info set and is inserted in
9719 * the rbtree, update the space info's counters.
9721 ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
9722 &cache->space_info);
9724 btrfs_remove_free_space_cache(cache);
9725 spin_lock(&root->fs_info->block_group_cache_lock);
9726 rb_erase(&cache->cache_node,
9727 &root->fs_info->block_group_cache_tree);
9728 RB_CLEAR_NODE(&cache->cache_node);
9729 spin_unlock(&root->fs_info->block_group_cache_lock);
9730 btrfs_put_block_group(cache);
9733 update_global_block_rsv(root->fs_info);
9735 spin_lock(&cache->space_info->lock);
9736 cache->space_info->bytes_readonly += cache->bytes_super;
9737 spin_unlock(&cache->space_info->lock);
9739 __link_block_group(cache->space_info, cache);
9741 list_add_tail(&cache->bg_list, &trans->new_bgs);
9743 set_avail_alloc_bits(extent_root->fs_info, type);
9748 static void clear_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
9750 u64 extra_flags = chunk_to_extended(flags) &
9751 BTRFS_EXTENDED_PROFILE_MASK;
9753 write_seqlock(&fs_info->profiles_lock);
9754 if (flags & BTRFS_BLOCK_GROUP_DATA)
9755 fs_info->avail_data_alloc_bits &= ~extra_flags;
9756 if (flags & BTRFS_BLOCK_GROUP_METADATA)
9757 fs_info->avail_metadata_alloc_bits &= ~extra_flags;
9758 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
9759 fs_info->avail_system_alloc_bits &= ~extra_flags;
9760 write_sequnlock(&fs_info->profiles_lock);
9763 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
9764 struct btrfs_root *root, u64 group_start,
9765 struct extent_map *em)
9767 struct btrfs_path *path;
9768 struct btrfs_block_group_cache *block_group;
9769 struct btrfs_free_cluster *cluster;
9770 struct btrfs_root *tree_root = root->fs_info->tree_root;
9771 struct btrfs_key key;
9772 struct inode *inode;
9773 struct kobject *kobj = NULL;
9777 struct btrfs_caching_control *caching_ctl = NULL;
9780 root = root->fs_info->extent_root;
9782 block_group = btrfs_lookup_block_group(root->fs_info, group_start);
9783 BUG_ON(!block_group);
9784 BUG_ON(!block_group->ro);
9787 * Free the reserved super bytes from this block group before
9790 free_excluded_extents(root, block_group);
9792 memcpy(&key, &block_group->key, sizeof(key));
9793 index = get_block_group_index(block_group);
9794 if (block_group->flags & (BTRFS_BLOCK_GROUP_DUP |
9795 BTRFS_BLOCK_GROUP_RAID1 |
9796 BTRFS_BLOCK_GROUP_RAID10))
9801 /* make sure this block group isn't part of an allocation cluster */
9802 cluster = &root->fs_info->data_alloc_cluster;
9803 spin_lock(&cluster->refill_lock);
9804 btrfs_return_cluster_to_free_space(block_group, cluster);
9805 spin_unlock(&cluster->refill_lock);
9808 * make sure this block group isn't part of a metadata
9809 * allocation cluster
9811 cluster = &root->fs_info->meta_alloc_cluster;
9812 spin_lock(&cluster->refill_lock);
9813 btrfs_return_cluster_to_free_space(block_group, cluster);
9814 spin_unlock(&cluster->refill_lock);
9816 path = btrfs_alloc_path();
9823 * get the inode first so any iput calls done for the io_list
9824 * aren't the final iput (no unlinks allowed now)
9826 inode = lookup_free_space_inode(tree_root, block_group, path);
9828 mutex_lock(&trans->transaction->cache_write_mutex);
9830 * make sure our free spache cache IO is done before remove the
9833 spin_lock(&trans->transaction->dirty_bgs_lock);
9834 if (!list_empty(&block_group->io_list)) {
9835 list_del_init(&block_group->io_list);
9837 WARN_ON(!IS_ERR(inode) && inode != block_group->io_ctl.inode);
9839 spin_unlock(&trans->transaction->dirty_bgs_lock);
9840 btrfs_wait_cache_io(root, trans, block_group,
9841 &block_group->io_ctl, path,
9842 block_group->key.objectid);
9843 btrfs_put_block_group(block_group);
9844 spin_lock(&trans->transaction->dirty_bgs_lock);
9847 if (!list_empty(&block_group->dirty_list)) {
9848 list_del_init(&block_group->dirty_list);
9849 btrfs_put_block_group(block_group);
9851 spin_unlock(&trans->transaction->dirty_bgs_lock);
9852 mutex_unlock(&trans->transaction->cache_write_mutex);
9854 if (!IS_ERR(inode)) {
9855 ret = btrfs_orphan_add(trans, inode);
9857 btrfs_add_delayed_iput(inode);
9861 /* One for the block groups ref */
9862 spin_lock(&block_group->lock);
9863 if (block_group->iref) {
9864 block_group->iref = 0;
9865 block_group->inode = NULL;
9866 spin_unlock(&block_group->lock);
9869 spin_unlock(&block_group->lock);
9871 /* One for our lookup ref */
9872 btrfs_add_delayed_iput(inode);
9875 key.objectid = BTRFS_FREE_SPACE_OBJECTID;
9876 key.offset = block_group->key.objectid;
9879 ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1);
9883 btrfs_release_path(path);
9885 ret = btrfs_del_item(trans, tree_root, path);
9888 btrfs_release_path(path);
9891 spin_lock(&root->fs_info->block_group_cache_lock);
9892 rb_erase(&block_group->cache_node,
9893 &root->fs_info->block_group_cache_tree);
9894 RB_CLEAR_NODE(&block_group->cache_node);
9896 if (root->fs_info->first_logical_byte == block_group->key.objectid)
9897 root->fs_info->first_logical_byte = (u64)-1;
9898 spin_unlock(&root->fs_info->block_group_cache_lock);
9900 down_write(&block_group->space_info->groups_sem);
9902 * we must use list_del_init so people can check to see if they
9903 * are still on the list after taking the semaphore
9905 list_del_init(&block_group->list);
9906 if (list_empty(&block_group->space_info->block_groups[index])) {
9907 kobj = block_group->space_info->block_group_kobjs[index];
9908 block_group->space_info->block_group_kobjs[index] = NULL;
9909 clear_avail_alloc_bits(root->fs_info, block_group->flags);
9911 up_write(&block_group->space_info->groups_sem);
9917 if (block_group->has_caching_ctl)
9918 caching_ctl = get_caching_control(block_group);
9919 if (block_group->cached == BTRFS_CACHE_STARTED)
9920 wait_block_group_cache_done(block_group);
9921 if (block_group->has_caching_ctl) {
9922 down_write(&root->fs_info->commit_root_sem);
9924 struct btrfs_caching_control *ctl;
9926 list_for_each_entry(ctl,
9927 &root->fs_info->caching_block_groups, list)
9928 if (ctl->block_group == block_group) {
9930 atomic_inc(&caching_ctl->count);
9935 list_del_init(&caching_ctl->list);
9936 up_write(&root->fs_info->commit_root_sem);
9938 /* Once for the caching bgs list and once for us. */
9939 put_caching_control(caching_ctl);
9940 put_caching_control(caching_ctl);
9944 spin_lock(&trans->transaction->dirty_bgs_lock);
9945 if (!list_empty(&block_group->dirty_list)) {
9948 if (!list_empty(&block_group->io_list)) {
9951 spin_unlock(&trans->transaction->dirty_bgs_lock);
9952 btrfs_remove_free_space_cache(block_group);
9954 spin_lock(&block_group->space_info->lock);
9955 list_del_init(&block_group->ro_list);
9957 if (btrfs_test_opt(root, ENOSPC_DEBUG)) {
9958 WARN_ON(block_group->space_info->total_bytes
9959 < block_group->key.offset);
9960 WARN_ON(block_group->space_info->bytes_readonly
9961 < block_group->key.offset);
9962 WARN_ON(block_group->space_info->disk_total
9963 < block_group->key.offset * factor);
9965 block_group->space_info->total_bytes -= block_group->key.offset;
9966 block_group->space_info->bytes_readonly -= block_group->key.offset;
9967 block_group->space_info->disk_total -= block_group->key.offset * factor;
9969 spin_unlock(&block_group->space_info->lock);
9971 memcpy(&key, &block_group->key, sizeof(key));
9974 if (!list_empty(&em->list)) {
9975 /* We're in the transaction->pending_chunks list. */
9976 free_extent_map(em);
9978 spin_lock(&block_group->lock);
9979 block_group->removed = 1;
9981 * At this point trimming can't start on this block group, because we
9982 * removed the block group from the tree fs_info->block_group_cache_tree
9983 * so no one can't find it anymore and even if someone already got this
9984 * block group before we removed it from the rbtree, they have already
9985 * incremented block_group->trimming - if they didn't, they won't find
9986 * any free space entries because we already removed them all when we
9987 * called btrfs_remove_free_space_cache().
9989 * And we must not remove the extent map from the fs_info->mapping_tree
9990 * to prevent the same logical address range and physical device space
9991 * ranges from being reused for a new block group. This is because our
9992 * fs trim operation (btrfs_trim_fs() / btrfs_ioctl_fitrim()) is
9993 * completely transactionless, so while it is trimming a range the
9994 * currently running transaction might finish and a new one start,
9995 * allowing for new block groups to be created that can reuse the same
9996 * physical device locations unless we take this special care.
9998 * There may also be an implicit trim operation if the file system
9999 * is mounted with -odiscard. The same protections must remain
10000 * in place until the extents have been discarded completely when
10001 * the transaction commit has completed.
10003 remove_em = (atomic_read(&block_group->trimming) == 0);
10005 * Make sure a trimmer task always sees the em in the pinned_chunks list
10006 * if it sees block_group->removed == 1 (needs to lock block_group->lock
10007 * before checking block_group->removed).
10011 * Our em might be in trans->transaction->pending_chunks which
10012 * is protected by fs_info->chunk_mutex ([lock|unlock]_chunks),
10013 * and so is the fs_info->pinned_chunks list.
10015 * So at this point we must be holding the chunk_mutex to avoid
10016 * any races with chunk allocation (more specifically at
10017 * volumes.c:contains_pending_extent()), to ensure it always
10018 * sees the em, either in the pending_chunks list or in the
10019 * pinned_chunks list.
10021 list_move_tail(&em->list, &root->fs_info->pinned_chunks);
10023 spin_unlock(&block_group->lock);
10026 struct extent_map_tree *em_tree;
10028 em_tree = &root->fs_info->mapping_tree.map_tree;
10029 write_lock(&em_tree->lock);
10031 * The em might be in the pending_chunks list, so make sure the
10032 * chunk mutex is locked, since remove_extent_mapping() will
10033 * delete us from that list.
10035 remove_extent_mapping(em_tree, em);
10036 write_unlock(&em_tree->lock);
10037 /* once for the tree */
10038 free_extent_map(em);
10041 unlock_chunks(root);
10043 btrfs_put_block_group(block_group);
10044 btrfs_put_block_group(block_group);
10046 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
10052 ret = btrfs_del_item(trans, root, path);
10054 btrfs_free_path(path);
10059 * Process the unused_bgs list and remove any that don't have any allocated
10060 * space inside of them.
10062 void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info)
10064 struct btrfs_block_group_cache *block_group;
10065 struct btrfs_space_info *space_info;
10066 struct btrfs_root *root = fs_info->extent_root;
10067 struct btrfs_trans_handle *trans;
10070 if (!fs_info->open)
10073 spin_lock(&fs_info->unused_bgs_lock);
10074 while (!list_empty(&fs_info->unused_bgs)) {
10078 block_group = list_first_entry(&fs_info->unused_bgs,
10079 struct btrfs_block_group_cache,
10081 space_info = block_group->space_info;
10082 list_del_init(&block_group->bg_list);
10083 if (ret || btrfs_mixed_space_info(space_info)) {
10084 btrfs_put_block_group(block_group);
10087 spin_unlock(&fs_info->unused_bgs_lock);
10089 mutex_lock(&root->fs_info->delete_unused_bgs_mutex);
10091 /* Don't want to race with allocators so take the groups_sem */
10092 down_write(&space_info->groups_sem);
10093 spin_lock(&block_group->lock);
10094 if (block_group->reserved ||
10095 btrfs_block_group_used(&block_group->item) ||
10098 * We want to bail if we made new allocations or have
10099 * outstanding allocations in this block group. We do
10100 * the ro check in case balance is currently acting on
10101 * this block group.
10103 spin_unlock(&block_group->lock);
10104 up_write(&space_info->groups_sem);
10107 spin_unlock(&block_group->lock);
10109 /* We don't want to force the issue, only flip if it's ok. */
10110 ret = inc_block_group_ro(block_group, 0);
10111 up_write(&space_info->groups_sem);
10118 * Want to do this before we do anything else so we can recover
10119 * properly if we fail to join the transaction.
10121 /* 1 for btrfs_orphan_reserve_metadata() */
10122 trans = btrfs_start_transaction(root, 1);
10123 if (IS_ERR(trans)) {
10124 btrfs_dec_block_group_ro(root, block_group);
10125 ret = PTR_ERR(trans);
10130 * We could have pending pinned extents for this block group,
10131 * just delete them, we don't care about them anymore.
10133 start = block_group->key.objectid;
10134 end = start + block_group->key.offset - 1;
10136 * Hold the unused_bg_unpin_mutex lock to avoid racing with
10137 * btrfs_finish_extent_commit(). If we are at transaction N,
10138 * another task might be running finish_extent_commit() for the
10139 * previous transaction N - 1, and have seen a range belonging
10140 * to the block group in freed_extents[] before we were able to
10141 * clear the whole block group range from freed_extents[]. This
10142 * means that task can lookup for the block group after we
10143 * unpinned it from freed_extents[] and removed it, leading to
10144 * a BUG_ON() at btrfs_unpin_extent_range().
10146 mutex_lock(&fs_info->unused_bg_unpin_mutex);
10147 ret = clear_extent_bits(&fs_info->freed_extents[0], start, end,
10148 EXTENT_DIRTY, GFP_NOFS);
10150 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
10151 btrfs_dec_block_group_ro(root, block_group);
10154 ret = clear_extent_bits(&fs_info->freed_extents[1], start, end,
10155 EXTENT_DIRTY, GFP_NOFS);
10157 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
10158 btrfs_dec_block_group_ro(root, block_group);
10161 mutex_unlock(&fs_info->unused_bg_unpin_mutex);
10163 /* Reset pinned so btrfs_put_block_group doesn't complain */
10164 spin_lock(&space_info->lock);
10165 spin_lock(&block_group->lock);
10167 space_info->bytes_pinned -= block_group->pinned;
10168 space_info->bytes_readonly += block_group->pinned;
10169 percpu_counter_add(&space_info->total_bytes_pinned,
10170 -block_group->pinned);
10171 block_group->pinned = 0;
10173 spin_unlock(&block_group->lock);
10174 spin_unlock(&space_info->lock);
10176 /* DISCARD can flip during remount */
10177 trimming = btrfs_test_opt(root, DISCARD);
10179 /* Implicit trim during transaction commit. */
10181 btrfs_get_block_group_trimming(block_group);
10184 * Btrfs_remove_chunk will abort the transaction if things go
10187 ret = btrfs_remove_chunk(trans, root,
10188 block_group->key.objectid);
10192 btrfs_put_block_group_trimming(block_group);
10197 * If we're not mounted with -odiscard, we can just forget
10198 * about this block group. Otherwise we'll need to wait
10199 * until transaction commit to do the actual discard.
10202 WARN_ON(!list_empty(&block_group->bg_list));
10203 spin_lock(&trans->transaction->deleted_bgs_lock);
10204 list_move(&block_group->bg_list,
10205 &trans->transaction->deleted_bgs);
10206 spin_unlock(&trans->transaction->deleted_bgs_lock);
10207 btrfs_get_block_group(block_group);
10210 btrfs_end_transaction(trans, root);
10212 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
10213 btrfs_put_block_group(block_group);
10214 spin_lock(&fs_info->unused_bgs_lock);
10216 spin_unlock(&fs_info->unused_bgs_lock);
10219 int btrfs_init_space_info(struct btrfs_fs_info *fs_info)
10221 struct btrfs_space_info *space_info;
10222 struct btrfs_super_block *disk_super;
10228 disk_super = fs_info->super_copy;
10229 if (!btrfs_super_root(disk_super))
10232 features = btrfs_super_incompat_flags(disk_super);
10233 if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
10236 flags = BTRFS_BLOCK_GROUP_SYSTEM;
10237 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
10242 flags = BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA;
10243 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
10245 flags = BTRFS_BLOCK_GROUP_METADATA;
10246 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
10250 flags = BTRFS_BLOCK_GROUP_DATA;
10251 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
10257 int btrfs_error_unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
10259 return unpin_extent_range(root, start, end, false);
10263 * It used to be that old block groups would be left around forever.
10264 * Iterating over them would be enough to trim unused space. Since we
10265 * now automatically remove them, we also need to iterate over unallocated
10268 * We don't want a transaction for this since the discard may take a
10269 * substantial amount of time. We don't require that a transaction be
10270 * running, but we do need to take a running transaction into account
10271 * to ensure that we're not discarding chunks that were released in
10272 * the current transaction.
10274 * Holding the chunks lock will prevent other threads from allocating
10275 * or releasing chunks, but it won't prevent a running transaction
10276 * from committing and releasing the memory that the pending chunks
10277 * list head uses. For that, we need to take a reference to the
10280 static int btrfs_trim_free_extents(struct btrfs_device *device,
10281 u64 minlen, u64 *trimmed)
10283 u64 start = 0, len = 0;
10288 /* Not writeable = nothing to do. */
10289 if (!device->writeable)
10292 /* No free space = nothing to do. */
10293 if (device->total_bytes <= device->bytes_used)
10299 struct btrfs_fs_info *fs_info = device->dev_root->fs_info;
10300 struct btrfs_transaction *trans;
10303 ret = mutex_lock_interruptible(&fs_info->chunk_mutex);
10307 down_read(&fs_info->commit_root_sem);
10309 spin_lock(&fs_info->trans_lock);
10310 trans = fs_info->running_transaction;
10312 atomic_inc(&trans->use_count);
10313 spin_unlock(&fs_info->trans_lock);
10315 ret = find_free_dev_extent_start(trans, device, minlen, start,
10318 btrfs_put_transaction(trans);
10321 up_read(&fs_info->commit_root_sem);
10322 mutex_unlock(&fs_info->chunk_mutex);
10323 if (ret == -ENOSPC)
10328 ret = btrfs_issue_discard(device->bdev, start, len, &bytes);
10329 up_read(&fs_info->commit_root_sem);
10330 mutex_unlock(&fs_info->chunk_mutex);
10338 if (fatal_signal_pending(current)) {
10339 ret = -ERESTARTSYS;
10349 int btrfs_trim_fs(struct btrfs_root *root, struct fstrim_range *range)
10351 struct btrfs_fs_info *fs_info = root->fs_info;
10352 struct btrfs_block_group_cache *cache = NULL;
10353 struct btrfs_device *device;
10354 struct list_head *devices;
10359 u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
10363 * try to trim all FS space, our block group may start from non-zero.
10365 if (range->len == total_bytes)
10366 cache = btrfs_lookup_first_block_group(fs_info, range->start);
10368 cache = btrfs_lookup_block_group(fs_info, range->start);
10371 if (cache->key.objectid >= (range->start + range->len)) {
10372 btrfs_put_block_group(cache);
10376 start = max(range->start, cache->key.objectid);
10377 end = min(range->start + range->len,
10378 cache->key.objectid + cache->key.offset);
10380 if (end - start >= range->minlen) {
10381 if (!block_group_cache_done(cache)) {
10382 ret = cache_block_group(cache, 0);
10384 btrfs_put_block_group(cache);
10387 ret = wait_block_group_cache_done(cache);
10389 btrfs_put_block_group(cache);
10393 ret = btrfs_trim_block_group(cache,
10399 trimmed += group_trimmed;
10401 btrfs_put_block_group(cache);
10406 cache = next_block_group(fs_info->tree_root, cache);
10409 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
10410 devices = &root->fs_info->fs_devices->alloc_list;
10411 list_for_each_entry(device, devices, dev_alloc_list) {
10412 ret = btrfs_trim_free_extents(device, range->minlen,
10417 trimmed += group_trimmed;
10419 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
10421 range->len = trimmed;
10426 * btrfs_{start,end}_write_no_snapshoting() are similar to
10427 * mnt_{want,drop}_write(), they are used to prevent some tasks from writing
10428 * data into the page cache through nocow before the subvolume is snapshoted,
10429 * but flush the data into disk after the snapshot creation, or to prevent
10430 * operations while snapshoting is ongoing and that cause the snapshot to be
10431 * inconsistent (writes followed by expanding truncates for example).
10433 void btrfs_end_write_no_snapshoting(struct btrfs_root *root)
10435 percpu_counter_dec(&root->subv_writers->counter);
10437 * Make sure counter is updated before we wake up waiters.
10440 if (waitqueue_active(&root->subv_writers->wait))
10441 wake_up(&root->subv_writers->wait);
10444 int btrfs_start_write_no_snapshoting(struct btrfs_root *root)
10446 if (atomic_read(&root->will_be_snapshoted))
10449 percpu_counter_inc(&root->subv_writers->counter);
10451 * Make sure counter is updated before we check for snapshot creation.
10454 if (atomic_read(&root->will_be_snapshoted)) {
10455 btrfs_end_write_no_snapshoting(root);