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>
31 #include "print-tree.h"
32 #include "transaction.h"
35 #include "free-space-cache.h"
38 * control flags for do_chunk_alloc's force field
39 * CHUNK_ALLOC_NO_FORCE means to only allocate a chunk
40 * if we really need one.
42 * CHUNK_ALLOC_LIMITED means to only try and allocate one
43 * if we have very few chunks already allocated. This is
44 * used as part of the clustering code to help make sure
45 * we have a good pool of storage to cluster in, without
46 * filling the FS with empty chunks
48 * CHUNK_ALLOC_FORCE means it must try to allocate one
52 CHUNK_ALLOC_NO_FORCE = 0,
53 CHUNK_ALLOC_LIMITED = 1,
54 CHUNK_ALLOC_FORCE = 2,
58 * Control how reservations are dealt with.
60 * RESERVE_FREE - freeing a reservation.
61 * RESERVE_ALLOC - allocating space and we need to update bytes_may_use for
63 * RESERVE_ALLOC_NO_ACCOUNT - allocating space and we should not update
64 * bytes_may_use as the ENOSPC accounting is done elsewhere
69 RESERVE_ALLOC_NO_ACCOUNT = 2,
72 static int update_block_group(struct btrfs_trans_handle *trans,
73 struct btrfs_root *root,
74 u64 bytenr, u64 num_bytes, int alloc);
75 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
76 struct btrfs_root *root,
77 u64 bytenr, u64 num_bytes, u64 parent,
78 u64 root_objectid, u64 owner_objectid,
79 u64 owner_offset, int refs_to_drop,
80 struct btrfs_delayed_extent_op *extra_op);
81 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
82 struct extent_buffer *leaf,
83 struct btrfs_extent_item *ei);
84 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
85 struct btrfs_root *root,
86 u64 parent, u64 root_objectid,
87 u64 flags, u64 owner, u64 offset,
88 struct btrfs_key *ins, int ref_mod);
89 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
90 struct btrfs_root *root,
91 u64 parent, u64 root_objectid,
92 u64 flags, struct btrfs_disk_key *key,
93 int level, struct btrfs_key *ins);
94 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
95 struct btrfs_root *extent_root, u64 alloc_bytes,
96 u64 flags, int force);
97 static int find_next_key(struct btrfs_path *path, int level,
98 struct btrfs_key *key);
99 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
100 int dump_block_groups);
101 static int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache,
102 u64 num_bytes, int reserve);
105 block_group_cache_done(struct btrfs_block_group_cache *cache)
108 return cache->cached == BTRFS_CACHE_FINISHED;
111 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
113 return (cache->flags & bits) == bits;
116 static void btrfs_get_block_group(struct btrfs_block_group_cache *cache)
118 atomic_inc(&cache->count);
121 void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
123 if (atomic_dec_and_test(&cache->count)) {
124 WARN_ON(cache->pinned > 0);
125 WARN_ON(cache->reserved > 0);
126 kfree(cache->free_space_ctl);
132 * this adds the block group to the fs_info rb tree for the block group
135 static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
136 struct btrfs_block_group_cache *block_group)
139 struct rb_node *parent = NULL;
140 struct btrfs_block_group_cache *cache;
142 spin_lock(&info->block_group_cache_lock);
143 p = &info->block_group_cache_tree.rb_node;
147 cache = rb_entry(parent, struct btrfs_block_group_cache,
149 if (block_group->key.objectid < cache->key.objectid) {
151 } else if (block_group->key.objectid > cache->key.objectid) {
154 spin_unlock(&info->block_group_cache_lock);
159 rb_link_node(&block_group->cache_node, parent, p);
160 rb_insert_color(&block_group->cache_node,
161 &info->block_group_cache_tree);
162 spin_unlock(&info->block_group_cache_lock);
168 * This will return the block group at or after bytenr if contains is 0, else
169 * it will return the block group that contains the bytenr
171 static struct btrfs_block_group_cache *
172 block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
175 struct btrfs_block_group_cache *cache, *ret = NULL;
179 spin_lock(&info->block_group_cache_lock);
180 n = info->block_group_cache_tree.rb_node;
183 cache = rb_entry(n, struct btrfs_block_group_cache,
185 end = cache->key.objectid + cache->key.offset - 1;
186 start = cache->key.objectid;
188 if (bytenr < start) {
189 if (!contains && (!ret || start < ret->key.objectid))
192 } else if (bytenr > start) {
193 if (contains && bytenr <= end) {
204 btrfs_get_block_group(ret);
205 spin_unlock(&info->block_group_cache_lock);
210 static int add_excluded_extent(struct btrfs_root *root,
211 u64 start, u64 num_bytes)
213 u64 end = start + num_bytes - 1;
214 set_extent_bits(&root->fs_info->freed_extents[0],
215 start, end, EXTENT_UPTODATE, GFP_NOFS);
216 set_extent_bits(&root->fs_info->freed_extents[1],
217 start, end, EXTENT_UPTODATE, GFP_NOFS);
221 static void free_excluded_extents(struct btrfs_root *root,
222 struct btrfs_block_group_cache *cache)
226 start = cache->key.objectid;
227 end = start + cache->key.offset - 1;
229 clear_extent_bits(&root->fs_info->freed_extents[0],
230 start, end, EXTENT_UPTODATE, GFP_NOFS);
231 clear_extent_bits(&root->fs_info->freed_extents[1],
232 start, end, EXTENT_UPTODATE, GFP_NOFS);
235 static int exclude_super_stripes(struct btrfs_root *root,
236 struct btrfs_block_group_cache *cache)
243 if (cache->key.objectid < BTRFS_SUPER_INFO_OFFSET) {
244 stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->key.objectid;
245 cache->bytes_super += stripe_len;
246 ret = add_excluded_extent(root, cache->key.objectid,
251 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
252 bytenr = btrfs_sb_offset(i);
253 ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
254 cache->key.objectid, bytenr,
255 0, &logical, &nr, &stripe_len);
259 cache->bytes_super += stripe_len;
260 ret = add_excluded_extent(root, logical[nr],
270 static struct btrfs_caching_control *
271 get_caching_control(struct btrfs_block_group_cache *cache)
273 struct btrfs_caching_control *ctl;
275 spin_lock(&cache->lock);
276 if (cache->cached != BTRFS_CACHE_STARTED) {
277 spin_unlock(&cache->lock);
281 /* We're loading it the fast way, so we don't have a caching_ctl. */
282 if (!cache->caching_ctl) {
283 spin_unlock(&cache->lock);
287 ctl = cache->caching_ctl;
288 atomic_inc(&ctl->count);
289 spin_unlock(&cache->lock);
293 static void put_caching_control(struct btrfs_caching_control *ctl)
295 if (atomic_dec_and_test(&ctl->count))
300 * this is only called by cache_block_group, since we could have freed extents
301 * we need to check the pinned_extents for any extents that can't be used yet
302 * since their free space will be released as soon as the transaction commits.
304 static u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
305 struct btrfs_fs_info *info, u64 start, u64 end)
307 u64 extent_start, extent_end, size, total_added = 0;
310 while (start < end) {
311 ret = find_first_extent_bit(info->pinned_extents, start,
312 &extent_start, &extent_end,
313 EXTENT_DIRTY | EXTENT_UPTODATE);
317 if (extent_start <= start) {
318 start = extent_end + 1;
319 } else if (extent_start > start && extent_start < end) {
320 size = extent_start - start;
322 ret = btrfs_add_free_space(block_group, start,
325 start = extent_end + 1;
334 ret = btrfs_add_free_space(block_group, start, size);
341 static noinline void caching_thread(struct btrfs_work *work)
343 struct btrfs_block_group_cache *block_group;
344 struct btrfs_fs_info *fs_info;
345 struct btrfs_caching_control *caching_ctl;
346 struct btrfs_root *extent_root;
347 struct btrfs_path *path;
348 struct extent_buffer *leaf;
349 struct btrfs_key key;
355 caching_ctl = container_of(work, struct btrfs_caching_control, work);
356 block_group = caching_ctl->block_group;
357 fs_info = block_group->fs_info;
358 extent_root = fs_info->extent_root;
360 path = btrfs_alloc_path();
364 last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
367 * We don't want to deadlock with somebody trying to allocate a new
368 * extent for the extent root while also trying to search the extent
369 * root to add free space. So we skip locking and search the commit
370 * root, since its read-only
372 path->skip_locking = 1;
373 path->search_commit_root = 1;
378 key.type = BTRFS_EXTENT_ITEM_KEY;
380 mutex_lock(&caching_ctl->mutex);
381 /* need to make sure the commit_root doesn't disappear */
382 down_read(&fs_info->extent_commit_sem);
384 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
388 leaf = path->nodes[0];
389 nritems = btrfs_header_nritems(leaf);
392 if (btrfs_fs_closing(fs_info) > 1) {
397 if (path->slots[0] < nritems) {
398 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
400 ret = find_next_key(path, 0, &key);
404 if (need_resched() ||
405 btrfs_next_leaf(extent_root, path)) {
406 caching_ctl->progress = last;
407 btrfs_release_path(path);
408 up_read(&fs_info->extent_commit_sem);
409 mutex_unlock(&caching_ctl->mutex);
413 leaf = path->nodes[0];
414 nritems = btrfs_header_nritems(leaf);
418 if (key.objectid < block_group->key.objectid) {
423 if (key.objectid >= block_group->key.objectid +
424 block_group->key.offset)
427 if (key.type == BTRFS_EXTENT_ITEM_KEY) {
428 total_found += add_new_free_space(block_group,
431 last = key.objectid + key.offset;
433 if (total_found > (1024 * 1024 * 2)) {
435 wake_up(&caching_ctl->wait);
442 total_found += add_new_free_space(block_group, fs_info, last,
443 block_group->key.objectid +
444 block_group->key.offset);
445 caching_ctl->progress = (u64)-1;
447 spin_lock(&block_group->lock);
448 block_group->caching_ctl = NULL;
449 block_group->cached = BTRFS_CACHE_FINISHED;
450 spin_unlock(&block_group->lock);
453 btrfs_free_path(path);
454 up_read(&fs_info->extent_commit_sem);
456 free_excluded_extents(extent_root, block_group);
458 mutex_unlock(&caching_ctl->mutex);
460 wake_up(&caching_ctl->wait);
462 put_caching_control(caching_ctl);
463 btrfs_put_block_group(block_group);
466 static int cache_block_group(struct btrfs_block_group_cache *cache,
467 struct btrfs_trans_handle *trans,
468 struct btrfs_root *root,
472 struct btrfs_fs_info *fs_info = cache->fs_info;
473 struct btrfs_caching_control *caching_ctl;
476 caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_NOFS);
477 BUG_ON(!caching_ctl);
479 INIT_LIST_HEAD(&caching_ctl->list);
480 mutex_init(&caching_ctl->mutex);
481 init_waitqueue_head(&caching_ctl->wait);
482 caching_ctl->block_group = cache;
483 caching_ctl->progress = cache->key.objectid;
484 atomic_set(&caching_ctl->count, 1);
485 caching_ctl->work.func = caching_thread;
487 spin_lock(&cache->lock);
489 * This should be a rare occasion, but this could happen I think in the
490 * case where one thread starts to load the space cache info, and then
491 * some other thread starts a transaction commit which tries to do an
492 * allocation while the other thread is still loading the space cache
493 * info. The previous loop should have kept us from choosing this block
494 * group, but if we've moved to the state where we will wait on caching
495 * block groups we need to first check if we're doing a fast load here,
496 * so we can wait for it to finish, otherwise we could end up allocating
497 * from a block group who's cache gets evicted for one reason or
500 while (cache->cached == BTRFS_CACHE_FAST) {
501 struct btrfs_caching_control *ctl;
503 ctl = cache->caching_ctl;
504 atomic_inc(&ctl->count);
505 prepare_to_wait(&ctl->wait, &wait, TASK_UNINTERRUPTIBLE);
506 spin_unlock(&cache->lock);
510 finish_wait(&ctl->wait, &wait);
511 put_caching_control(ctl);
512 spin_lock(&cache->lock);
515 if (cache->cached != BTRFS_CACHE_NO) {
516 spin_unlock(&cache->lock);
520 WARN_ON(cache->caching_ctl);
521 cache->caching_ctl = caching_ctl;
522 cache->cached = BTRFS_CACHE_FAST;
523 spin_unlock(&cache->lock);
526 * We can't do the read from on-disk cache during a commit since we need
527 * to have the normal tree locking. Also if we are currently trying to
528 * allocate blocks for the tree root we can't do the fast caching since
529 * we likely hold important locks.
531 if (trans && (!trans->transaction->in_commit) &&
532 (root && root != root->fs_info->tree_root) &&
533 btrfs_test_opt(root, SPACE_CACHE)) {
534 ret = load_free_space_cache(fs_info, cache);
536 spin_lock(&cache->lock);
538 cache->caching_ctl = NULL;
539 cache->cached = BTRFS_CACHE_FINISHED;
540 cache->last_byte_to_unpin = (u64)-1;
542 if (load_cache_only) {
543 cache->caching_ctl = NULL;
544 cache->cached = BTRFS_CACHE_NO;
546 cache->cached = BTRFS_CACHE_STARTED;
549 spin_unlock(&cache->lock);
550 wake_up(&caching_ctl->wait);
552 put_caching_control(caching_ctl);
553 free_excluded_extents(fs_info->extent_root, cache);
558 * We are not going to do the fast caching, set cached to the
559 * appropriate value and wakeup any waiters.
561 spin_lock(&cache->lock);
562 if (load_cache_only) {
563 cache->caching_ctl = NULL;
564 cache->cached = BTRFS_CACHE_NO;
566 cache->cached = BTRFS_CACHE_STARTED;
568 spin_unlock(&cache->lock);
569 wake_up(&caching_ctl->wait);
572 if (load_cache_only) {
573 put_caching_control(caching_ctl);
577 down_write(&fs_info->extent_commit_sem);
578 atomic_inc(&caching_ctl->count);
579 list_add_tail(&caching_ctl->list, &fs_info->caching_block_groups);
580 up_write(&fs_info->extent_commit_sem);
582 btrfs_get_block_group(cache);
584 btrfs_queue_worker(&fs_info->caching_workers, &caching_ctl->work);
590 * return the block group that starts at or after bytenr
592 static struct btrfs_block_group_cache *
593 btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr)
595 struct btrfs_block_group_cache *cache;
597 cache = block_group_cache_tree_search(info, bytenr, 0);
603 * return the block group that contains the given bytenr
605 struct btrfs_block_group_cache *btrfs_lookup_block_group(
606 struct btrfs_fs_info *info,
609 struct btrfs_block_group_cache *cache;
611 cache = block_group_cache_tree_search(info, bytenr, 1);
616 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
619 struct list_head *head = &info->space_info;
620 struct btrfs_space_info *found;
622 flags &= BTRFS_BLOCK_GROUP_TYPE_MASK;
625 list_for_each_entry_rcu(found, head, list) {
626 if (found->flags & flags) {
636 * after adding space to the filesystem, we need to clear the full flags
637 * on all the space infos.
639 void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
641 struct list_head *head = &info->space_info;
642 struct btrfs_space_info *found;
645 list_for_each_entry_rcu(found, head, list)
650 static u64 div_factor(u64 num, int factor)
659 static u64 div_factor_fine(u64 num, int factor)
668 u64 btrfs_find_block_group(struct btrfs_root *root,
669 u64 search_start, u64 search_hint, int owner)
671 struct btrfs_block_group_cache *cache;
673 u64 last = max(search_hint, search_start);
680 cache = btrfs_lookup_first_block_group(root->fs_info, last);
684 spin_lock(&cache->lock);
685 last = cache->key.objectid + cache->key.offset;
686 used = btrfs_block_group_used(&cache->item);
688 if ((full_search || !cache->ro) &&
689 block_group_bits(cache, BTRFS_BLOCK_GROUP_METADATA)) {
690 if (used + cache->pinned + cache->reserved <
691 div_factor(cache->key.offset, factor)) {
692 group_start = cache->key.objectid;
693 spin_unlock(&cache->lock);
694 btrfs_put_block_group(cache);
698 spin_unlock(&cache->lock);
699 btrfs_put_block_group(cache);
707 if (!full_search && factor < 10) {
717 /* simple helper to search for an existing extent at a given offset */
718 int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len)
721 struct btrfs_key key;
722 struct btrfs_path *path;
724 path = btrfs_alloc_path();
728 key.objectid = start;
730 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
731 ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path,
733 btrfs_free_path(path);
738 * helper function to lookup reference count and flags of extent.
740 * the head node for delayed ref is used to store the sum of all the
741 * reference count modifications queued up in the rbtree. the head
742 * node may also store the extent flags to set. This way you can check
743 * to see what the reference count and extent flags would be if all of
744 * the delayed refs are not processed.
746 int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
747 struct btrfs_root *root, u64 bytenr,
748 u64 num_bytes, u64 *refs, u64 *flags)
750 struct btrfs_delayed_ref_head *head;
751 struct btrfs_delayed_ref_root *delayed_refs;
752 struct btrfs_path *path;
753 struct btrfs_extent_item *ei;
754 struct extent_buffer *leaf;
755 struct btrfs_key key;
761 path = btrfs_alloc_path();
765 key.objectid = bytenr;
766 key.type = BTRFS_EXTENT_ITEM_KEY;
767 key.offset = num_bytes;
769 path->skip_locking = 1;
770 path->search_commit_root = 1;
773 ret = btrfs_search_slot(trans, root->fs_info->extent_root,
779 leaf = path->nodes[0];
780 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
781 if (item_size >= sizeof(*ei)) {
782 ei = btrfs_item_ptr(leaf, path->slots[0],
783 struct btrfs_extent_item);
784 num_refs = btrfs_extent_refs(leaf, ei);
785 extent_flags = btrfs_extent_flags(leaf, ei);
787 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
788 struct btrfs_extent_item_v0 *ei0;
789 BUG_ON(item_size != sizeof(*ei0));
790 ei0 = btrfs_item_ptr(leaf, path->slots[0],
791 struct btrfs_extent_item_v0);
792 num_refs = btrfs_extent_refs_v0(leaf, ei0);
793 /* FIXME: this isn't correct for data */
794 extent_flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
799 BUG_ON(num_refs == 0);
809 delayed_refs = &trans->transaction->delayed_refs;
810 spin_lock(&delayed_refs->lock);
811 head = btrfs_find_delayed_ref_head(trans, bytenr);
813 if (!mutex_trylock(&head->mutex)) {
814 atomic_inc(&head->node.refs);
815 spin_unlock(&delayed_refs->lock);
817 btrfs_release_path(path);
820 * Mutex was contended, block until it's released and try
823 mutex_lock(&head->mutex);
824 mutex_unlock(&head->mutex);
825 btrfs_put_delayed_ref(&head->node);
828 if (head->extent_op && head->extent_op->update_flags)
829 extent_flags |= head->extent_op->flags_to_set;
831 BUG_ON(num_refs == 0);
833 num_refs += head->node.ref_mod;
834 mutex_unlock(&head->mutex);
836 spin_unlock(&delayed_refs->lock);
838 WARN_ON(num_refs == 0);
842 *flags = extent_flags;
844 btrfs_free_path(path);
849 * Back reference rules. Back refs have three main goals:
851 * 1) differentiate between all holders of references to an extent so that
852 * when a reference is dropped we can make sure it was a valid reference
853 * before freeing the extent.
855 * 2) Provide enough information to quickly find the holders of an extent
856 * if we notice a given block is corrupted or bad.
858 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
859 * maintenance. This is actually the same as #2, but with a slightly
860 * different use case.
862 * There are two kinds of back refs. The implicit back refs is optimized
863 * for pointers in non-shared tree blocks. For a given pointer in a block,
864 * back refs of this kind provide information about the block's owner tree
865 * and the pointer's key. These information allow us to find the block by
866 * b-tree searching. The full back refs is for pointers in tree blocks not
867 * referenced by their owner trees. The location of tree block is recorded
868 * in the back refs. Actually the full back refs is generic, and can be
869 * used in all cases the implicit back refs is used. The major shortcoming
870 * of the full back refs is its overhead. Every time a tree block gets
871 * COWed, we have to update back refs entry for all pointers in it.
873 * For a newly allocated tree block, we use implicit back refs for
874 * pointers in it. This means most tree related operations only involve
875 * implicit back refs. For a tree block created in old transaction, the
876 * only way to drop a reference to it is COW it. So we can detect the
877 * event that tree block loses its owner tree's reference and do the
878 * back refs conversion.
880 * When a tree block is COW'd through a tree, there are four cases:
882 * The reference count of the block is one and the tree is the block's
883 * owner tree. Nothing to do in this case.
885 * The reference count of the block is one and the tree is not the
886 * block's owner tree. In this case, full back refs is used for pointers
887 * in the block. Remove these full back refs, add implicit back refs for
888 * every pointers in the new block.
890 * The reference count of the block is greater than one and the tree is
891 * the block's owner tree. In this case, implicit back refs is used for
892 * pointers in the block. Add full back refs for every pointers in the
893 * block, increase lower level extents' reference counts. The original
894 * implicit back refs are entailed to the new block.
896 * The reference count of the block is greater than one and the tree is
897 * not the block's owner tree. Add implicit back refs for every pointer in
898 * the new block, increase lower level extents' reference count.
900 * Back Reference Key composing:
902 * The key objectid corresponds to the first byte in the extent,
903 * The key type is used to differentiate between types of back refs.
904 * There are different meanings of the key offset for different types
907 * File extents can be referenced by:
909 * - multiple snapshots, subvolumes, or different generations in one subvol
910 * - different files inside a single subvolume
911 * - different offsets inside a file (bookend extents in file.c)
913 * The extent ref structure for the implicit back refs has fields for:
915 * - Objectid of the subvolume root
916 * - objectid of the file holding the reference
917 * - original offset in the file
918 * - how many bookend extents
920 * The key offset for the implicit back refs is hash of the first
923 * The extent ref structure for the full back refs has field for:
925 * - number of pointers in the tree leaf
927 * The key offset for the implicit back refs is the first byte of
930 * When a file extent is allocated, The implicit back refs is used.
931 * the fields are filled in:
933 * (root_key.objectid, inode objectid, offset in file, 1)
935 * When a file extent is removed file truncation, we find the
936 * corresponding implicit back refs and check the following fields:
938 * (btrfs_header_owner(leaf), inode objectid, offset in file)
940 * Btree extents can be referenced by:
942 * - Different subvolumes
944 * Both the implicit back refs and the full back refs for tree blocks
945 * only consist of key. The key offset for the implicit back refs is
946 * objectid of block's owner tree. The key offset for the full back refs
947 * is the first byte of parent block.
949 * When implicit back refs is used, information about the lowest key and
950 * level of the tree block are required. These information are stored in
951 * tree block info structure.
954 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
955 static int convert_extent_item_v0(struct btrfs_trans_handle *trans,
956 struct btrfs_root *root,
957 struct btrfs_path *path,
958 u64 owner, u32 extra_size)
960 struct btrfs_extent_item *item;
961 struct btrfs_extent_item_v0 *ei0;
962 struct btrfs_extent_ref_v0 *ref0;
963 struct btrfs_tree_block_info *bi;
964 struct extent_buffer *leaf;
965 struct btrfs_key key;
966 struct btrfs_key found_key;
967 u32 new_size = sizeof(*item);
971 leaf = path->nodes[0];
972 BUG_ON(btrfs_item_size_nr(leaf, path->slots[0]) != sizeof(*ei0));
974 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
975 ei0 = btrfs_item_ptr(leaf, path->slots[0],
976 struct btrfs_extent_item_v0);
977 refs = btrfs_extent_refs_v0(leaf, ei0);
979 if (owner == (u64)-1) {
981 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
982 ret = btrfs_next_leaf(root, path);
986 leaf = path->nodes[0];
988 btrfs_item_key_to_cpu(leaf, &found_key,
990 BUG_ON(key.objectid != found_key.objectid);
991 if (found_key.type != BTRFS_EXTENT_REF_V0_KEY) {
995 ref0 = btrfs_item_ptr(leaf, path->slots[0],
996 struct btrfs_extent_ref_v0);
997 owner = btrfs_ref_objectid_v0(leaf, ref0);
1001 btrfs_release_path(path);
1003 if (owner < BTRFS_FIRST_FREE_OBJECTID)
1004 new_size += sizeof(*bi);
1006 new_size -= sizeof(*ei0);
1007 ret = btrfs_search_slot(trans, root, &key, path,
1008 new_size + extra_size, 1);
1013 btrfs_extend_item(trans, root, path, new_size);
1015 leaf = path->nodes[0];
1016 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1017 btrfs_set_extent_refs(leaf, item, refs);
1018 /* FIXME: get real generation */
1019 btrfs_set_extent_generation(leaf, item, 0);
1020 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1021 btrfs_set_extent_flags(leaf, item,
1022 BTRFS_EXTENT_FLAG_TREE_BLOCK |
1023 BTRFS_BLOCK_FLAG_FULL_BACKREF);
1024 bi = (struct btrfs_tree_block_info *)(item + 1);
1025 /* FIXME: get first key of the block */
1026 memset_extent_buffer(leaf, 0, (unsigned long)bi, sizeof(*bi));
1027 btrfs_set_tree_block_level(leaf, bi, (int)owner);
1029 btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_DATA);
1031 btrfs_mark_buffer_dirty(leaf);
1036 static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
1038 u32 high_crc = ~(u32)0;
1039 u32 low_crc = ~(u32)0;
1042 lenum = cpu_to_le64(root_objectid);
1043 high_crc = crc32c(high_crc, &lenum, sizeof(lenum));
1044 lenum = cpu_to_le64(owner);
1045 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
1046 lenum = cpu_to_le64(offset);
1047 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
1049 return ((u64)high_crc << 31) ^ (u64)low_crc;
1052 static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
1053 struct btrfs_extent_data_ref *ref)
1055 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
1056 btrfs_extent_data_ref_objectid(leaf, ref),
1057 btrfs_extent_data_ref_offset(leaf, ref));
1060 static int match_extent_data_ref(struct extent_buffer *leaf,
1061 struct btrfs_extent_data_ref *ref,
1062 u64 root_objectid, u64 owner, u64 offset)
1064 if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
1065 btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
1066 btrfs_extent_data_ref_offset(leaf, ref) != offset)
1071 static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
1072 struct btrfs_root *root,
1073 struct btrfs_path *path,
1074 u64 bytenr, u64 parent,
1076 u64 owner, u64 offset)
1078 struct btrfs_key key;
1079 struct btrfs_extent_data_ref *ref;
1080 struct extent_buffer *leaf;
1086 key.objectid = bytenr;
1088 key.type = BTRFS_SHARED_DATA_REF_KEY;
1089 key.offset = parent;
1091 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1092 key.offset = hash_extent_data_ref(root_objectid,
1097 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1106 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1107 key.type = BTRFS_EXTENT_REF_V0_KEY;
1108 btrfs_release_path(path);
1109 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1120 leaf = path->nodes[0];
1121 nritems = btrfs_header_nritems(leaf);
1123 if (path->slots[0] >= nritems) {
1124 ret = btrfs_next_leaf(root, path);
1130 leaf = path->nodes[0];
1131 nritems = btrfs_header_nritems(leaf);
1135 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1136 if (key.objectid != bytenr ||
1137 key.type != BTRFS_EXTENT_DATA_REF_KEY)
1140 ref = btrfs_item_ptr(leaf, path->slots[0],
1141 struct btrfs_extent_data_ref);
1143 if (match_extent_data_ref(leaf, ref, root_objectid,
1146 btrfs_release_path(path);
1158 static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
1159 struct btrfs_root *root,
1160 struct btrfs_path *path,
1161 u64 bytenr, u64 parent,
1162 u64 root_objectid, u64 owner,
1163 u64 offset, int refs_to_add)
1165 struct btrfs_key key;
1166 struct extent_buffer *leaf;
1171 key.objectid = bytenr;
1173 key.type = BTRFS_SHARED_DATA_REF_KEY;
1174 key.offset = parent;
1175 size = sizeof(struct btrfs_shared_data_ref);
1177 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1178 key.offset = hash_extent_data_ref(root_objectid,
1180 size = sizeof(struct btrfs_extent_data_ref);
1183 ret = btrfs_insert_empty_item(trans, root, path, &key, size);
1184 if (ret && ret != -EEXIST)
1187 leaf = path->nodes[0];
1189 struct btrfs_shared_data_ref *ref;
1190 ref = btrfs_item_ptr(leaf, path->slots[0],
1191 struct btrfs_shared_data_ref);
1193 btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
1195 num_refs = btrfs_shared_data_ref_count(leaf, ref);
1196 num_refs += refs_to_add;
1197 btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
1200 struct btrfs_extent_data_ref *ref;
1201 while (ret == -EEXIST) {
1202 ref = btrfs_item_ptr(leaf, path->slots[0],
1203 struct btrfs_extent_data_ref);
1204 if (match_extent_data_ref(leaf, ref, root_objectid,
1207 btrfs_release_path(path);
1209 ret = btrfs_insert_empty_item(trans, root, path, &key,
1211 if (ret && ret != -EEXIST)
1214 leaf = path->nodes[0];
1216 ref = btrfs_item_ptr(leaf, path->slots[0],
1217 struct btrfs_extent_data_ref);
1219 btrfs_set_extent_data_ref_root(leaf, ref,
1221 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
1222 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
1223 btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
1225 num_refs = btrfs_extent_data_ref_count(leaf, ref);
1226 num_refs += refs_to_add;
1227 btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
1230 btrfs_mark_buffer_dirty(leaf);
1233 btrfs_release_path(path);
1237 static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
1238 struct btrfs_root *root,
1239 struct btrfs_path *path,
1242 struct btrfs_key key;
1243 struct btrfs_extent_data_ref *ref1 = NULL;
1244 struct btrfs_shared_data_ref *ref2 = NULL;
1245 struct extent_buffer *leaf;
1249 leaf = path->nodes[0];
1250 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1252 if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1253 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1254 struct btrfs_extent_data_ref);
1255 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1256 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1257 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1258 struct btrfs_shared_data_ref);
1259 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1260 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1261 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1262 struct btrfs_extent_ref_v0 *ref0;
1263 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1264 struct btrfs_extent_ref_v0);
1265 num_refs = btrfs_ref_count_v0(leaf, ref0);
1271 BUG_ON(num_refs < refs_to_drop);
1272 num_refs -= refs_to_drop;
1274 if (num_refs == 0) {
1275 ret = btrfs_del_item(trans, root, path);
1277 if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
1278 btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
1279 else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
1280 btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
1281 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1283 struct btrfs_extent_ref_v0 *ref0;
1284 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1285 struct btrfs_extent_ref_v0);
1286 btrfs_set_ref_count_v0(leaf, ref0, num_refs);
1289 btrfs_mark_buffer_dirty(leaf);
1294 static noinline u32 extent_data_ref_count(struct btrfs_root *root,
1295 struct btrfs_path *path,
1296 struct btrfs_extent_inline_ref *iref)
1298 struct btrfs_key key;
1299 struct extent_buffer *leaf;
1300 struct btrfs_extent_data_ref *ref1;
1301 struct btrfs_shared_data_ref *ref2;
1304 leaf = path->nodes[0];
1305 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1307 if (btrfs_extent_inline_ref_type(leaf, iref) ==
1308 BTRFS_EXTENT_DATA_REF_KEY) {
1309 ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
1310 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1312 ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
1313 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1315 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1316 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1317 struct btrfs_extent_data_ref);
1318 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1319 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1320 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1321 struct btrfs_shared_data_ref);
1322 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1323 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1324 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1325 struct btrfs_extent_ref_v0 *ref0;
1326 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1327 struct btrfs_extent_ref_v0);
1328 num_refs = btrfs_ref_count_v0(leaf, ref0);
1336 static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
1337 struct btrfs_root *root,
1338 struct btrfs_path *path,
1339 u64 bytenr, u64 parent,
1342 struct btrfs_key key;
1345 key.objectid = bytenr;
1347 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1348 key.offset = parent;
1350 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1351 key.offset = root_objectid;
1354 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1357 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1358 if (ret == -ENOENT && parent) {
1359 btrfs_release_path(path);
1360 key.type = BTRFS_EXTENT_REF_V0_KEY;
1361 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1369 static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
1370 struct btrfs_root *root,
1371 struct btrfs_path *path,
1372 u64 bytenr, u64 parent,
1375 struct btrfs_key key;
1378 key.objectid = bytenr;
1380 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1381 key.offset = parent;
1383 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1384 key.offset = root_objectid;
1387 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1388 btrfs_release_path(path);
1392 static inline int extent_ref_type(u64 parent, u64 owner)
1395 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1397 type = BTRFS_SHARED_BLOCK_REF_KEY;
1399 type = BTRFS_TREE_BLOCK_REF_KEY;
1402 type = BTRFS_SHARED_DATA_REF_KEY;
1404 type = BTRFS_EXTENT_DATA_REF_KEY;
1409 static int find_next_key(struct btrfs_path *path, int level,
1410 struct btrfs_key *key)
1413 for (; level < BTRFS_MAX_LEVEL; level++) {
1414 if (!path->nodes[level])
1416 if (path->slots[level] + 1 >=
1417 btrfs_header_nritems(path->nodes[level]))
1420 btrfs_item_key_to_cpu(path->nodes[level], key,
1421 path->slots[level] + 1);
1423 btrfs_node_key_to_cpu(path->nodes[level], key,
1424 path->slots[level] + 1);
1431 * look for inline back ref. if back ref is found, *ref_ret is set
1432 * to the address of inline back ref, and 0 is returned.
1434 * if back ref isn't found, *ref_ret is set to the address where it
1435 * should be inserted, and -ENOENT is returned.
1437 * if insert is true and there are too many inline back refs, the path
1438 * points to the extent item, and -EAGAIN is returned.
1440 * NOTE: inline back refs are ordered in the same way that back ref
1441 * items in the tree are ordered.
1443 static noinline_for_stack
1444 int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
1445 struct btrfs_root *root,
1446 struct btrfs_path *path,
1447 struct btrfs_extent_inline_ref **ref_ret,
1448 u64 bytenr, u64 num_bytes,
1449 u64 parent, u64 root_objectid,
1450 u64 owner, u64 offset, int insert)
1452 struct btrfs_key key;
1453 struct extent_buffer *leaf;
1454 struct btrfs_extent_item *ei;
1455 struct btrfs_extent_inline_ref *iref;
1466 key.objectid = bytenr;
1467 key.type = BTRFS_EXTENT_ITEM_KEY;
1468 key.offset = num_bytes;
1470 want = extent_ref_type(parent, owner);
1472 extra_size = btrfs_extent_inline_ref_size(want);
1473 path->keep_locks = 1;
1476 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
1483 leaf = path->nodes[0];
1484 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1485 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1486 if (item_size < sizeof(*ei)) {
1491 ret = convert_extent_item_v0(trans, root, path, owner,
1497 leaf = path->nodes[0];
1498 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1501 BUG_ON(item_size < sizeof(*ei));
1503 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1504 flags = btrfs_extent_flags(leaf, ei);
1506 ptr = (unsigned long)(ei + 1);
1507 end = (unsigned long)ei + item_size;
1509 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
1510 ptr += sizeof(struct btrfs_tree_block_info);
1513 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_DATA));
1522 iref = (struct btrfs_extent_inline_ref *)ptr;
1523 type = btrfs_extent_inline_ref_type(leaf, iref);
1527 ptr += btrfs_extent_inline_ref_size(type);
1531 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1532 struct btrfs_extent_data_ref *dref;
1533 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1534 if (match_extent_data_ref(leaf, dref, root_objectid,
1539 if (hash_extent_data_ref_item(leaf, dref) <
1540 hash_extent_data_ref(root_objectid, owner, offset))
1544 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1546 if (parent == ref_offset) {
1550 if (ref_offset < parent)
1553 if (root_objectid == ref_offset) {
1557 if (ref_offset < root_objectid)
1561 ptr += btrfs_extent_inline_ref_size(type);
1563 if (err == -ENOENT && insert) {
1564 if (item_size + extra_size >=
1565 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
1570 * To add new inline back ref, we have to make sure
1571 * there is no corresponding back ref item.
1572 * For simplicity, we just do not add new inline back
1573 * ref if there is any kind of item for this block
1575 if (find_next_key(path, 0, &key) == 0 &&
1576 key.objectid == bytenr &&
1577 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
1582 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
1585 path->keep_locks = 0;
1586 btrfs_unlock_up_safe(path, 1);
1592 * helper to add new inline back ref
1594 static noinline_for_stack
1595 void setup_inline_extent_backref(struct btrfs_trans_handle *trans,
1596 struct btrfs_root *root,
1597 struct btrfs_path *path,
1598 struct btrfs_extent_inline_ref *iref,
1599 u64 parent, u64 root_objectid,
1600 u64 owner, u64 offset, int refs_to_add,
1601 struct btrfs_delayed_extent_op *extent_op)
1603 struct extent_buffer *leaf;
1604 struct btrfs_extent_item *ei;
1607 unsigned long item_offset;
1612 leaf = path->nodes[0];
1613 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1614 item_offset = (unsigned long)iref - (unsigned long)ei;
1616 type = extent_ref_type(parent, owner);
1617 size = btrfs_extent_inline_ref_size(type);
1619 btrfs_extend_item(trans, root, path, size);
1621 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1622 refs = btrfs_extent_refs(leaf, ei);
1623 refs += refs_to_add;
1624 btrfs_set_extent_refs(leaf, ei, refs);
1626 __run_delayed_extent_op(extent_op, leaf, ei);
1628 ptr = (unsigned long)ei + item_offset;
1629 end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
1630 if (ptr < end - size)
1631 memmove_extent_buffer(leaf, ptr + size, ptr,
1634 iref = (struct btrfs_extent_inline_ref *)ptr;
1635 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1636 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1637 struct btrfs_extent_data_ref *dref;
1638 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1639 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1640 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1641 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1642 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1643 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1644 struct btrfs_shared_data_ref *sref;
1645 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1646 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1647 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1648 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1649 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1651 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1653 btrfs_mark_buffer_dirty(leaf);
1656 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1657 struct btrfs_root *root,
1658 struct btrfs_path *path,
1659 struct btrfs_extent_inline_ref **ref_ret,
1660 u64 bytenr, u64 num_bytes, u64 parent,
1661 u64 root_objectid, u64 owner, u64 offset)
1665 ret = lookup_inline_extent_backref(trans, root, path, ref_ret,
1666 bytenr, num_bytes, parent,
1667 root_objectid, owner, offset, 0);
1671 btrfs_release_path(path);
1674 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1675 ret = lookup_tree_block_ref(trans, root, path, bytenr, parent,
1678 ret = lookup_extent_data_ref(trans, root, path, bytenr, parent,
1679 root_objectid, owner, offset);
1685 * helper to update/remove inline back ref
1687 static noinline_for_stack
1688 void update_inline_extent_backref(struct btrfs_trans_handle *trans,
1689 struct btrfs_root *root,
1690 struct btrfs_path *path,
1691 struct btrfs_extent_inline_ref *iref,
1693 struct btrfs_delayed_extent_op *extent_op)
1695 struct extent_buffer *leaf;
1696 struct btrfs_extent_item *ei;
1697 struct btrfs_extent_data_ref *dref = NULL;
1698 struct btrfs_shared_data_ref *sref = NULL;
1706 leaf = path->nodes[0];
1707 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1708 refs = btrfs_extent_refs(leaf, ei);
1709 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1710 refs += refs_to_mod;
1711 btrfs_set_extent_refs(leaf, ei, refs);
1713 __run_delayed_extent_op(extent_op, leaf, ei);
1715 type = btrfs_extent_inline_ref_type(leaf, iref);
1717 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1718 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1719 refs = btrfs_extent_data_ref_count(leaf, dref);
1720 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1721 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1722 refs = btrfs_shared_data_ref_count(leaf, sref);
1725 BUG_ON(refs_to_mod != -1);
1728 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1729 refs += refs_to_mod;
1732 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1733 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1735 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1737 size = btrfs_extent_inline_ref_size(type);
1738 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1739 ptr = (unsigned long)iref;
1740 end = (unsigned long)ei + item_size;
1741 if (ptr + size < end)
1742 memmove_extent_buffer(leaf, ptr, ptr + size,
1745 btrfs_truncate_item(trans, root, path, item_size, 1);
1747 btrfs_mark_buffer_dirty(leaf);
1750 static noinline_for_stack
1751 int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1752 struct btrfs_root *root,
1753 struct btrfs_path *path,
1754 u64 bytenr, u64 num_bytes, u64 parent,
1755 u64 root_objectid, u64 owner,
1756 u64 offset, int refs_to_add,
1757 struct btrfs_delayed_extent_op *extent_op)
1759 struct btrfs_extent_inline_ref *iref;
1762 ret = lookup_inline_extent_backref(trans, root, path, &iref,
1763 bytenr, num_bytes, parent,
1764 root_objectid, owner, offset, 1);
1766 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
1767 update_inline_extent_backref(trans, root, path, iref,
1768 refs_to_add, extent_op);
1769 } else if (ret == -ENOENT) {
1770 setup_inline_extent_backref(trans, root, path, iref, parent,
1771 root_objectid, owner, offset,
1772 refs_to_add, extent_op);
1778 static int insert_extent_backref(struct btrfs_trans_handle *trans,
1779 struct btrfs_root *root,
1780 struct btrfs_path *path,
1781 u64 bytenr, u64 parent, u64 root_objectid,
1782 u64 owner, u64 offset, int refs_to_add)
1785 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1786 BUG_ON(refs_to_add != 1);
1787 ret = insert_tree_block_ref(trans, root, path, bytenr,
1788 parent, root_objectid);
1790 ret = insert_extent_data_ref(trans, root, path, bytenr,
1791 parent, root_objectid,
1792 owner, offset, refs_to_add);
1797 static int remove_extent_backref(struct btrfs_trans_handle *trans,
1798 struct btrfs_root *root,
1799 struct btrfs_path *path,
1800 struct btrfs_extent_inline_ref *iref,
1801 int refs_to_drop, int is_data)
1805 BUG_ON(!is_data && refs_to_drop != 1);
1807 update_inline_extent_backref(trans, root, path, iref,
1808 -refs_to_drop, NULL);
1809 } else if (is_data) {
1810 ret = remove_extent_data_ref(trans, root, path, refs_to_drop);
1812 ret = btrfs_del_item(trans, root, path);
1817 static int btrfs_issue_discard(struct block_device *bdev,
1820 return blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_NOFS, 0);
1823 static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
1824 u64 num_bytes, u64 *actual_bytes)
1827 u64 discarded_bytes = 0;
1828 struct btrfs_bio *bbio = NULL;
1831 /* Tell the block device(s) that the sectors can be discarded */
1832 ret = btrfs_map_block(&root->fs_info->mapping_tree, REQ_DISCARD,
1833 bytenr, &num_bytes, &bbio, 0);
1835 struct btrfs_bio_stripe *stripe = bbio->stripes;
1839 for (i = 0; i < bbio->num_stripes; i++, stripe++) {
1840 if (!stripe->dev->can_discard)
1843 ret = btrfs_issue_discard(stripe->dev->bdev,
1847 discarded_bytes += stripe->length;
1848 else if (ret != -EOPNOTSUPP)
1852 * Just in case we get back EOPNOTSUPP for some reason,
1853 * just ignore the return value so we don't screw up
1854 * people calling discard_extent.
1862 *actual_bytes = discarded_bytes;
1868 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1869 struct btrfs_root *root,
1870 u64 bytenr, u64 num_bytes, u64 parent,
1871 u64 root_objectid, u64 owner, u64 offset, int for_cow)
1874 struct btrfs_fs_info *fs_info = root->fs_info;
1876 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID &&
1877 root_objectid == BTRFS_TREE_LOG_OBJECTID);
1879 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1880 ret = btrfs_add_delayed_tree_ref(fs_info, trans, bytenr,
1882 parent, root_objectid, (int)owner,
1883 BTRFS_ADD_DELAYED_REF, NULL, for_cow);
1885 ret = btrfs_add_delayed_data_ref(fs_info, trans, bytenr,
1887 parent, root_objectid, owner, offset,
1888 BTRFS_ADD_DELAYED_REF, NULL, for_cow);
1893 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1894 struct btrfs_root *root,
1895 u64 bytenr, u64 num_bytes,
1896 u64 parent, u64 root_objectid,
1897 u64 owner, u64 offset, int refs_to_add,
1898 struct btrfs_delayed_extent_op *extent_op)
1900 struct btrfs_path *path;
1901 struct extent_buffer *leaf;
1902 struct btrfs_extent_item *item;
1907 path = btrfs_alloc_path();
1912 path->leave_spinning = 1;
1913 /* this will setup the path even if it fails to insert the back ref */
1914 ret = insert_inline_extent_backref(trans, root->fs_info->extent_root,
1915 path, bytenr, num_bytes, parent,
1916 root_objectid, owner, offset,
1917 refs_to_add, extent_op);
1921 if (ret != -EAGAIN) {
1926 leaf = path->nodes[0];
1927 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1928 refs = btrfs_extent_refs(leaf, item);
1929 btrfs_set_extent_refs(leaf, item, refs + refs_to_add);
1931 __run_delayed_extent_op(extent_op, leaf, item);
1933 btrfs_mark_buffer_dirty(leaf);
1934 btrfs_release_path(path);
1937 path->leave_spinning = 1;
1939 /* now insert the actual backref */
1940 ret = insert_extent_backref(trans, root->fs_info->extent_root,
1941 path, bytenr, parent, root_objectid,
1942 owner, offset, refs_to_add);
1945 btrfs_free_path(path);
1949 static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
1950 struct btrfs_root *root,
1951 struct btrfs_delayed_ref_node *node,
1952 struct btrfs_delayed_extent_op *extent_op,
1953 int insert_reserved)
1956 struct btrfs_delayed_data_ref *ref;
1957 struct btrfs_key ins;
1962 ins.objectid = node->bytenr;
1963 ins.offset = node->num_bytes;
1964 ins.type = BTRFS_EXTENT_ITEM_KEY;
1966 ref = btrfs_delayed_node_to_data_ref(node);
1967 if (node->type == BTRFS_SHARED_DATA_REF_KEY)
1968 parent = ref->parent;
1970 ref_root = ref->root;
1972 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
1974 BUG_ON(extent_op->update_key);
1975 flags |= extent_op->flags_to_set;
1977 ret = alloc_reserved_file_extent(trans, root,
1978 parent, ref_root, flags,
1979 ref->objectid, ref->offset,
1980 &ins, node->ref_mod);
1981 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
1982 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
1983 node->num_bytes, parent,
1984 ref_root, ref->objectid,
1985 ref->offset, node->ref_mod,
1987 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
1988 ret = __btrfs_free_extent(trans, root, node->bytenr,
1989 node->num_bytes, parent,
1990 ref_root, ref->objectid,
1991 ref->offset, node->ref_mod,
1999 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
2000 struct extent_buffer *leaf,
2001 struct btrfs_extent_item *ei)
2003 u64 flags = btrfs_extent_flags(leaf, ei);
2004 if (extent_op->update_flags) {
2005 flags |= extent_op->flags_to_set;
2006 btrfs_set_extent_flags(leaf, ei, flags);
2009 if (extent_op->update_key) {
2010 struct btrfs_tree_block_info *bi;
2011 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK));
2012 bi = (struct btrfs_tree_block_info *)(ei + 1);
2013 btrfs_set_tree_block_key(leaf, bi, &extent_op->key);
2017 static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
2018 struct btrfs_root *root,
2019 struct btrfs_delayed_ref_node *node,
2020 struct btrfs_delayed_extent_op *extent_op)
2022 struct btrfs_key key;
2023 struct btrfs_path *path;
2024 struct btrfs_extent_item *ei;
2025 struct extent_buffer *leaf;
2030 path = btrfs_alloc_path();
2034 key.objectid = node->bytenr;
2035 key.type = BTRFS_EXTENT_ITEM_KEY;
2036 key.offset = node->num_bytes;
2039 path->leave_spinning = 1;
2040 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key,
2051 leaf = path->nodes[0];
2052 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2053 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2054 if (item_size < sizeof(*ei)) {
2055 ret = convert_extent_item_v0(trans, root->fs_info->extent_root,
2061 leaf = path->nodes[0];
2062 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2065 BUG_ON(item_size < sizeof(*ei));
2066 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2067 __run_delayed_extent_op(extent_op, leaf, ei);
2069 btrfs_mark_buffer_dirty(leaf);
2071 btrfs_free_path(path);
2075 static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
2076 struct btrfs_root *root,
2077 struct btrfs_delayed_ref_node *node,
2078 struct btrfs_delayed_extent_op *extent_op,
2079 int insert_reserved)
2082 struct btrfs_delayed_tree_ref *ref;
2083 struct btrfs_key ins;
2087 ins.objectid = node->bytenr;
2088 ins.offset = node->num_bytes;
2089 ins.type = BTRFS_EXTENT_ITEM_KEY;
2091 ref = btrfs_delayed_node_to_tree_ref(node);
2092 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2093 parent = ref->parent;
2095 ref_root = ref->root;
2097 BUG_ON(node->ref_mod != 1);
2098 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
2099 BUG_ON(!extent_op || !extent_op->update_flags ||
2100 !extent_op->update_key);
2101 ret = alloc_reserved_tree_block(trans, root,
2103 extent_op->flags_to_set,
2106 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
2107 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
2108 node->num_bytes, parent, ref_root,
2109 ref->level, 0, 1, extent_op);
2110 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
2111 ret = __btrfs_free_extent(trans, root, node->bytenr,
2112 node->num_bytes, parent, ref_root,
2113 ref->level, 0, 1, extent_op);
2120 /* helper function to actually process a single delayed ref entry */
2121 static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
2122 struct btrfs_root *root,
2123 struct btrfs_delayed_ref_node *node,
2124 struct btrfs_delayed_extent_op *extent_op,
2125 int insert_reserved)
2128 if (btrfs_delayed_ref_is_head(node)) {
2129 struct btrfs_delayed_ref_head *head;
2131 * we've hit the end of the chain and we were supposed
2132 * to insert this extent into the tree. But, it got
2133 * deleted before we ever needed to insert it, so all
2134 * we have to do is clean up the accounting
2137 head = btrfs_delayed_node_to_head(node);
2138 if (insert_reserved) {
2139 btrfs_pin_extent(root, node->bytenr,
2140 node->num_bytes, 1);
2141 if (head->is_data) {
2142 ret = btrfs_del_csums(trans, root,
2148 mutex_unlock(&head->mutex);
2152 if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
2153 node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2154 ret = run_delayed_tree_ref(trans, root, node, extent_op,
2156 else if (node->type == BTRFS_EXTENT_DATA_REF_KEY ||
2157 node->type == BTRFS_SHARED_DATA_REF_KEY)
2158 ret = run_delayed_data_ref(trans, root, node, extent_op,
2165 static noinline struct btrfs_delayed_ref_node *
2166 select_delayed_ref(struct btrfs_delayed_ref_head *head)
2168 struct rb_node *node;
2169 struct btrfs_delayed_ref_node *ref;
2170 int action = BTRFS_ADD_DELAYED_REF;
2173 * select delayed ref of type BTRFS_ADD_DELAYED_REF first.
2174 * this prevents ref count from going down to zero when
2175 * there still are pending delayed ref.
2177 node = rb_prev(&head->node.rb_node);
2181 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2183 if (ref->bytenr != head->node.bytenr)
2185 if (ref->action == action)
2187 node = rb_prev(node);
2189 if (action == BTRFS_ADD_DELAYED_REF) {
2190 action = BTRFS_DROP_DELAYED_REF;
2196 static noinline int run_clustered_refs(struct btrfs_trans_handle *trans,
2197 struct btrfs_root *root,
2198 struct list_head *cluster)
2200 struct btrfs_delayed_ref_root *delayed_refs;
2201 struct btrfs_delayed_ref_node *ref;
2202 struct btrfs_delayed_ref_head *locked_ref = NULL;
2203 struct btrfs_delayed_extent_op *extent_op;
2206 int must_insert_reserved = 0;
2208 delayed_refs = &trans->transaction->delayed_refs;
2211 /* pick a new head ref from the cluster list */
2212 if (list_empty(cluster))
2215 locked_ref = list_entry(cluster->next,
2216 struct btrfs_delayed_ref_head, cluster);
2218 /* grab the lock that says we are going to process
2219 * all the refs for this head */
2220 ret = btrfs_delayed_ref_lock(trans, locked_ref);
2223 * we may have dropped the spin lock to get the head
2224 * mutex lock, and that might have given someone else
2225 * time to free the head. If that's true, it has been
2226 * removed from our list and we can move on.
2228 if (ret == -EAGAIN) {
2236 * locked_ref is the head node, so we have to go one
2237 * node back for any delayed ref updates
2239 ref = select_delayed_ref(locked_ref);
2241 if (ref && ref->seq &&
2242 btrfs_check_delayed_seq(delayed_refs, ref->seq)) {
2244 * there are still refs with lower seq numbers in the
2245 * process of being added. Don't run this ref yet.
2247 list_del_init(&locked_ref->cluster);
2248 mutex_unlock(&locked_ref->mutex);
2250 delayed_refs->num_heads_ready++;
2251 spin_unlock(&delayed_refs->lock);
2253 spin_lock(&delayed_refs->lock);
2258 * record the must insert reserved flag before we
2259 * drop the spin lock.
2261 must_insert_reserved = locked_ref->must_insert_reserved;
2262 locked_ref->must_insert_reserved = 0;
2264 extent_op = locked_ref->extent_op;
2265 locked_ref->extent_op = NULL;
2268 /* All delayed refs have been processed, Go ahead
2269 * and send the head node to run_one_delayed_ref,
2270 * so that any accounting fixes can happen
2272 ref = &locked_ref->node;
2274 if (extent_op && must_insert_reserved) {
2280 spin_unlock(&delayed_refs->lock);
2282 ret = run_delayed_extent_op(trans, root,
2290 list_del_init(&locked_ref->cluster);
2295 rb_erase(&ref->rb_node, &delayed_refs->root);
2296 delayed_refs->num_entries--;
2298 * we modified num_entries, but as we're currently running
2299 * delayed refs, skip
2300 * wake_up(&delayed_refs->seq_wait);
2303 spin_unlock(&delayed_refs->lock);
2305 ret = run_one_delayed_ref(trans, root, ref, extent_op,
2306 must_insert_reserved);
2309 btrfs_put_delayed_ref(ref);
2313 do_chunk_alloc(trans, root->fs_info->extent_root,
2315 btrfs_get_alloc_profile(root, 0),
2316 CHUNK_ALLOC_NO_FORCE);
2318 spin_lock(&delayed_refs->lock);
2324 static void wait_for_more_refs(struct btrfs_delayed_ref_root *delayed_refs,
2325 unsigned long num_refs)
2327 struct list_head *first_seq = delayed_refs->seq_head.next;
2329 spin_unlock(&delayed_refs->lock);
2330 pr_debug("waiting for more refs (num %ld, first %p)\n",
2331 num_refs, first_seq);
2332 wait_event(delayed_refs->seq_wait,
2333 num_refs != delayed_refs->num_entries ||
2334 delayed_refs->seq_head.next != first_seq);
2335 pr_debug("done waiting for more refs (num %ld, first %p)\n",
2336 delayed_refs->num_entries, delayed_refs->seq_head.next);
2337 spin_lock(&delayed_refs->lock);
2341 * this starts processing the delayed reference count updates and
2342 * extent insertions we have queued up so far. count can be
2343 * 0, which means to process everything in the tree at the start
2344 * of the run (but not newly added entries), or it can be some target
2345 * number you'd like to process.
2347 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2348 struct btrfs_root *root, unsigned long count)
2350 struct rb_node *node;
2351 struct btrfs_delayed_ref_root *delayed_refs;
2352 struct btrfs_delayed_ref_node *ref;
2353 struct list_head cluster;
2356 int run_all = count == (unsigned long)-1;
2358 unsigned long num_refs = 0;
2359 int consider_waiting;
2361 if (root == root->fs_info->extent_root)
2362 root = root->fs_info->tree_root;
2364 do_chunk_alloc(trans, root->fs_info->extent_root,
2365 2 * 1024 * 1024, btrfs_get_alloc_profile(root, 0),
2366 CHUNK_ALLOC_NO_FORCE);
2368 delayed_refs = &trans->transaction->delayed_refs;
2369 INIT_LIST_HEAD(&cluster);
2371 consider_waiting = 0;
2372 spin_lock(&delayed_refs->lock);
2374 count = delayed_refs->num_entries * 2;
2378 if (!(run_all || run_most) &&
2379 delayed_refs->num_heads_ready < 64)
2383 * go find something we can process in the rbtree. We start at
2384 * the beginning of the tree, and then build a cluster
2385 * of refs to process starting at the first one we are able to
2388 delayed_start = delayed_refs->run_delayed_start;
2389 ret = btrfs_find_ref_cluster(trans, &cluster,
2390 delayed_refs->run_delayed_start);
2394 if (delayed_start >= delayed_refs->run_delayed_start) {
2395 if (consider_waiting == 0) {
2397 * btrfs_find_ref_cluster looped. let's do one
2398 * more cycle. if we don't run any delayed ref
2399 * during that cycle (because we can't because
2400 * all of them are blocked) and if the number of
2401 * refs doesn't change, we avoid busy waiting.
2403 consider_waiting = 1;
2404 num_refs = delayed_refs->num_entries;
2406 wait_for_more_refs(delayed_refs, num_refs);
2408 * after waiting, things have changed. we
2409 * dropped the lock and someone else might have
2410 * run some refs, built new clusters and so on.
2411 * therefore, we restart staleness detection.
2413 consider_waiting = 0;
2417 ret = run_clustered_refs(trans, root, &cluster);
2420 count -= min_t(unsigned long, ret, count);
2425 if (ret || delayed_refs->run_delayed_start == 0) {
2426 /* refs were run, let's reset staleness detection */
2427 consider_waiting = 0;
2432 node = rb_first(&delayed_refs->root);
2435 count = (unsigned long)-1;
2438 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2440 if (btrfs_delayed_ref_is_head(ref)) {
2441 struct btrfs_delayed_ref_head *head;
2443 head = btrfs_delayed_node_to_head(ref);
2444 atomic_inc(&ref->refs);
2446 spin_unlock(&delayed_refs->lock);
2448 * Mutex was contended, block until it's
2449 * released and try again
2451 mutex_lock(&head->mutex);
2452 mutex_unlock(&head->mutex);
2454 btrfs_put_delayed_ref(ref);
2458 node = rb_next(node);
2460 spin_unlock(&delayed_refs->lock);
2461 schedule_timeout(1);
2465 spin_unlock(&delayed_refs->lock);
2469 int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
2470 struct btrfs_root *root,
2471 u64 bytenr, u64 num_bytes, u64 flags,
2474 struct btrfs_delayed_extent_op *extent_op;
2477 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
2481 extent_op->flags_to_set = flags;
2482 extent_op->update_flags = 1;
2483 extent_op->update_key = 0;
2484 extent_op->is_data = is_data ? 1 : 0;
2486 ret = btrfs_add_delayed_extent_op(root->fs_info, trans, bytenr,
2487 num_bytes, extent_op);
2493 static noinline int check_delayed_ref(struct btrfs_trans_handle *trans,
2494 struct btrfs_root *root,
2495 struct btrfs_path *path,
2496 u64 objectid, u64 offset, u64 bytenr)
2498 struct btrfs_delayed_ref_head *head;
2499 struct btrfs_delayed_ref_node *ref;
2500 struct btrfs_delayed_data_ref *data_ref;
2501 struct btrfs_delayed_ref_root *delayed_refs;
2502 struct rb_node *node;
2506 delayed_refs = &trans->transaction->delayed_refs;
2507 spin_lock(&delayed_refs->lock);
2508 head = btrfs_find_delayed_ref_head(trans, bytenr);
2512 if (!mutex_trylock(&head->mutex)) {
2513 atomic_inc(&head->node.refs);
2514 spin_unlock(&delayed_refs->lock);
2516 btrfs_release_path(path);
2519 * Mutex was contended, block until it's released and let
2522 mutex_lock(&head->mutex);
2523 mutex_unlock(&head->mutex);
2524 btrfs_put_delayed_ref(&head->node);
2528 node = rb_prev(&head->node.rb_node);
2532 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2534 if (ref->bytenr != bytenr)
2538 if (ref->type != BTRFS_EXTENT_DATA_REF_KEY)
2541 data_ref = btrfs_delayed_node_to_data_ref(ref);
2543 node = rb_prev(node);
2545 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2546 if (ref->bytenr == bytenr)
2550 if (data_ref->root != root->root_key.objectid ||
2551 data_ref->objectid != objectid || data_ref->offset != offset)
2556 mutex_unlock(&head->mutex);
2558 spin_unlock(&delayed_refs->lock);
2562 static noinline int check_committed_ref(struct btrfs_trans_handle *trans,
2563 struct btrfs_root *root,
2564 struct btrfs_path *path,
2565 u64 objectid, u64 offset, u64 bytenr)
2567 struct btrfs_root *extent_root = root->fs_info->extent_root;
2568 struct extent_buffer *leaf;
2569 struct btrfs_extent_data_ref *ref;
2570 struct btrfs_extent_inline_ref *iref;
2571 struct btrfs_extent_item *ei;
2572 struct btrfs_key key;
2576 key.objectid = bytenr;
2577 key.offset = (u64)-1;
2578 key.type = BTRFS_EXTENT_ITEM_KEY;
2580 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
2586 if (path->slots[0] == 0)
2590 leaf = path->nodes[0];
2591 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2593 if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY)
2597 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2598 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2599 if (item_size < sizeof(*ei)) {
2600 WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0));
2604 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2606 if (item_size != sizeof(*ei) +
2607 btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY))
2610 if (btrfs_extent_generation(leaf, ei) <=
2611 btrfs_root_last_snapshot(&root->root_item))
2614 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
2615 if (btrfs_extent_inline_ref_type(leaf, iref) !=
2616 BTRFS_EXTENT_DATA_REF_KEY)
2619 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
2620 if (btrfs_extent_refs(leaf, ei) !=
2621 btrfs_extent_data_ref_count(leaf, ref) ||
2622 btrfs_extent_data_ref_root(leaf, ref) !=
2623 root->root_key.objectid ||
2624 btrfs_extent_data_ref_objectid(leaf, ref) != objectid ||
2625 btrfs_extent_data_ref_offset(leaf, ref) != offset)
2633 int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans,
2634 struct btrfs_root *root,
2635 u64 objectid, u64 offset, u64 bytenr)
2637 struct btrfs_path *path;
2641 path = btrfs_alloc_path();
2646 ret = check_committed_ref(trans, root, path, objectid,
2648 if (ret && ret != -ENOENT)
2651 ret2 = check_delayed_ref(trans, root, path, objectid,
2653 } while (ret2 == -EAGAIN);
2655 if (ret2 && ret2 != -ENOENT) {
2660 if (ret != -ENOENT || ret2 != -ENOENT)
2663 btrfs_free_path(path);
2664 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
2669 static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
2670 struct btrfs_root *root,
2671 struct extent_buffer *buf,
2672 int full_backref, int inc, int for_cow)
2679 struct btrfs_key key;
2680 struct btrfs_file_extent_item *fi;
2684 int (*process_func)(struct btrfs_trans_handle *, struct btrfs_root *,
2685 u64, u64, u64, u64, u64, u64, int);
2687 ref_root = btrfs_header_owner(buf);
2688 nritems = btrfs_header_nritems(buf);
2689 level = btrfs_header_level(buf);
2691 if (!root->ref_cows && level == 0)
2695 process_func = btrfs_inc_extent_ref;
2697 process_func = btrfs_free_extent;
2700 parent = buf->start;
2704 for (i = 0; i < nritems; i++) {
2706 btrfs_item_key_to_cpu(buf, &key, i);
2707 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2709 fi = btrfs_item_ptr(buf, i,
2710 struct btrfs_file_extent_item);
2711 if (btrfs_file_extent_type(buf, fi) ==
2712 BTRFS_FILE_EXTENT_INLINE)
2714 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2718 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
2719 key.offset -= btrfs_file_extent_offset(buf, fi);
2720 ret = process_func(trans, root, bytenr, num_bytes,
2721 parent, ref_root, key.objectid,
2722 key.offset, for_cow);
2726 bytenr = btrfs_node_blockptr(buf, i);
2727 num_bytes = btrfs_level_size(root, level - 1);
2728 ret = process_func(trans, root, bytenr, num_bytes,
2729 parent, ref_root, level - 1, 0,
2741 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2742 struct extent_buffer *buf, int full_backref, int for_cow)
2744 return __btrfs_mod_ref(trans, root, buf, full_backref, 1, for_cow);
2747 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2748 struct extent_buffer *buf, int full_backref, int for_cow)
2750 return __btrfs_mod_ref(trans, root, buf, full_backref, 0, for_cow);
2753 static int write_one_cache_group(struct btrfs_trans_handle *trans,
2754 struct btrfs_root *root,
2755 struct btrfs_path *path,
2756 struct btrfs_block_group_cache *cache)
2759 struct btrfs_root *extent_root = root->fs_info->extent_root;
2761 struct extent_buffer *leaf;
2763 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
2768 leaf = path->nodes[0];
2769 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
2770 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
2771 btrfs_mark_buffer_dirty(leaf);
2772 btrfs_release_path(path);
2780 static struct btrfs_block_group_cache *
2781 next_block_group(struct btrfs_root *root,
2782 struct btrfs_block_group_cache *cache)
2784 struct rb_node *node;
2785 spin_lock(&root->fs_info->block_group_cache_lock);
2786 node = rb_next(&cache->cache_node);
2787 btrfs_put_block_group(cache);
2789 cache = rb_entry(node, struct btrfs_block_group_cache,
2791 btrfs_get_block_group(cache);
2794 spin_unlock(&root->fs_info->block_group_cache_lock);
2798 static int cache_save_setup(struct btrfs_block_group_cache *block_group,
2799 struct btrfs_trans_handle *trans,
2800 struct btrfs_path *path)
2802 struct btrfs_root *root = block_group->fs_info->tree_root;
2803 struct inode *inode = NULL;
2805 int dcs = BTRFS_DC_ERROR;
2811 * If this block group is smaller than 100 megs don't bother caching the
2814 if (block_group->key.offset < (100 * 1024 * 1024)) {
2815 spin_lock(&block_group->lock);
2816 block_group->disk_cache_state = BTRFS_DC_WRITTEN;
2817 spin_unlock(&block_group->lock);
2822 inode = lookup_free_space_inode(root, block_group, path);
2823 if (IS_ERR(inode) && PTR_ERR(inode) != -ENOENT) {
2824 ret = PTR_ERR(inode);
2825 btrfs_release_path(path);
2829 if (IS_ERR(inode)) {
2833 if (block_group->ro)
2836 ret = create_free_space_inode(root, trans, block_group, path);
2842 /* We've already setup this transaction, go ahead and exit */
2843 if (block_group->cache_generation == trans->transid &&
2844 i_size_read(inode)) {
2845 dcs = BTRFS_DC_SETUP;
2850 * We want to set the generation to 0, that way if anything goes wrong
2851 * from here on out we know not to trust this cache when we load up next
2854 BTRFS_I(inode)->generation = 0;
2855 ret = btrfs_update_inode(trans, root, inode);
2858 if (i_size_read(inode) > 0) {
2859 ret = btrfs_truncate_free_space_cache(root, trans, path,
2865 spin_lock(&block_group->lock);
2866 if (block_group->cached != BTRFS_CACHE_FINISHED) {
2867 /* We're not cached, don't bother trying to write stuff out */
2868 dcs = BTRFS_DC_WRITTEN;
2869 spin_unlock(&block_group->lock);
2872 spin_unlock(&block_group->lock);
2874 num_pages = (int)div64_u64(block_group->key.offset, 1024 * 1024 * 1024);
2879 * Just to make absolutely sure we have enough space, we're going to
2880 * preallocate 12 pages worth of space for each block group. In
2881 * practice we ought to use at most 8, but we need extra space so we can
2882 * add our header and have a terminator between the extents and the
2886 num_pages *= PAGE_CACHE_SIZE;
2888 ret = btrfs_check_data_free_space(inode, num_pages);
2892 ret = btrfs_prealloc_file_range_trans(inode, trans, 0, 0, num_pages,
2893 num_pages, num_pages,
2896 dcs = BTRFS_DC_SETUP;
2897 btrfs_free_reserved_data_space(inode, num_pages);
2902 btrfs_release_path(path);
2904 spin_lock(&block_group->lock);
2905 if (!ret && dcs == BTRFS_DC_SETUP)
2906 block_group->cache_generation = trans->transid;
2907 block_group->disk_cache_state = dcs;
2908 spin_unlock(&block_group->lock);
2913 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
2914 struct btrfs_root *root)
2916 struct btrfs_block_group_cache *cache;
2918 struct btrfs_path *path;
2921 path = btrfs_alloc_path();
2927 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2929 if (cache->disk_cache_state == BTRFS_DC_CLEAR)
2931 cache = next_block_group(root, cache);
2939 err = cache_save_setup(cache, trans, path);
2940 last = cache->key.objectid + cache->key.offset;
2941 btrfs_put_block_group(cache);
2946 err = btrfs_run_delayed_refs(trans, root,
2951 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2953 if (cache->disk_cache_state == BTRFS_DC_CLEAR) {
2954 btrfs_put_block_group(cache);
2960 cache = next_block_group(root, cache);
2969 if (cache->disk_cache_state == BTRFS_DC_SETUP)
2970 cache->disk_cache_state = BTRFS_DC_NEED_WRITE;
2972 last = cache->key.objectid + cache->key.offset;
2974 err = write_one_cache_group(trans, root, path, cache);
2976 btrfs_put_block_group(cache);
2981 * I don't think this is needed since we're just marking our
2982 * preallocated extent as written, but just in case it can't
2986 err = btrfs_run_delayed_refs(trans, root,
2991 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2994 * Really this shouldn't happen, but it could if we
2995 * couldn't write the entire preallocated extent and
2996 * splitting the extent resulted in a new block.
2999 btrfs_put_block_group(cache);
3002 if (cache->disk_cache_state == BTRFS_DC_NEED_WRITE)
3004 cache = next_block_group(root, cache);
3013 btrfs_write_out_cache(root, trans, cache, path);
3016 * If we didn't have an error then the cache state is still
3017 * NEED_WRITE, so we can set it to WRITTEN.
3019 if (cache->disk_cache_state == BTRFS_DC_NEED_WRITE)
3020 cache->disk_cache_state = BTRFS_DC_WRITTEN;
3021 last = cache->key.objectid + cache->key.offset;
3022 btrfs_put_block_group(cache);
3025 btrfs_free_path(path);
3029 int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr)
3031 struct btrfs_block_group_cache *block_group;
3034 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
3035 if (!block_group || block_group->ro)
3038 btrfs_put_block_group(block_group);
3042 static int update_space_info(struct btrfs_fs_info *info, u64 flags,
3043 u64 total_bytes, u64 bytes_used,
3044 struct btrfs_space_info **space_info)
3046 struct btrfs_space_info *found;
3050 if (flags & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
3051 BTRFS_BLOCK_GROUP_RAID10))
3056 found = __find_space_info(info, flags);
3058 spin_lock(&found->lock);
3059 found->total_bytes += total_bytes;
3060 found->disk_total += total_bytes * factor;
3061 found->bytes_used += bytes_used;
3062 found->disk_used += bytes_used * factor;
3064 spin_unlock(&found->lock);
3065 *space_info = found;
3068 found = kzalloc(sizeof(*found), GFP_NOFS);
3072 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
3073 INIT_LIST_HEAD(&found->block_groups[i]);
3074 init_rwsem(&found->groups_sem);
3075 spin_lock_init(&found->lock);
3076 found->flags = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
3077 found->total_bytes = total_bytes;
3078 found->disk_total = total_bytes * factor;
3079 found->bytes_used = bytes_used;
3080 found->disk_used = bytes_used * factor;
3081 found->bytes_pinned = 0;
3082 found->bytes_reserved = 0;
3083 found->bytes_readonly = 0;
3084 found->bytes_may_use = 0;
3086 found->force_alloc = CHUNK_ALLOC_NO_FORCE;
3087 found->chunk_alloc = 0;
3089 init_waitqueue_head(&found->wait);
3090 *space_info = found;
3091 list_add_rcu(&found->list, &info->space_info);
3095 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
3097 u64 extra_flags = flags & BTRFS_BLOCK_GROUP_PROFILE_MASK;
3099 /* chunk -> extended profile */
3100 if (extra_flags == 0)
3101 extra_flags = BTRFS_AVAIL_ALLOC_BIT_SINGLE;
3103 if (flags & BTRFS_BLOCK_GROUP_DATA)
3104 fs_info->avail_data_alloc_bits |= extra_flags;
3105 if (flags & BTRFS_BLOCK_GROUP_METADATA)
3106 fs_info->avail_metadata_alloc_bits |= extra_flags;
3107 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
3108 fs_info->avail_system_alloc_bits |= extra_flags;
3112 * @flags: available profiles in extended format (see ctree.h)
3114 * Returns reduced profile in chunk format. If profile changing is in
3115 * progress (either running or paused) picks the target profile (if it's
3116 * already available), otherwise falls back to plain reducing.
3118 u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
3121 * we add in the count of missing devices because we want
3122 * to make sure that any RAID levels on a degraded FS
3123 * continue to be honored.
3125 u64 num_devices = root->fs_info->fs_devices->rw_devices +
3126 root->fs_info->fs_devices->missing_devices;
3128 /* pick restriper's target profile if it's available */
3129 spin_lock(&root->fs_info->balance_lock);
3130 if (root->fs_info->balance_ctl) {
3131 struct btrfs_balance_control *bctl = root->fs_info->balance_ctl;
3134 if ((flags & BTRFS_BLOCK_GROUP_DATA) &&
3135 (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3136 (flags & bctl->data.target)) {
3137 tgt = BTRFS_BLOCK_GROUP_DATA | bctl->data.target;
3138 } else if ((flags & BTRFS_BLOCK_GROUP_SYSTEM) &&
3139 (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3140 (flags & bctl->sys.target)) {
3141 tgt = BTRFS_BLOCK_GROUP_SYSTEM | bctl->sys.target;
3142 } else if ((flags & BTRFS_BLOCK_GROUP_METADATA) &&
3143 (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3144 (flags & bctl->meta.target)) {
3145 tgt = BTRFS_BLOCK_GROUP_METADATA | bctl->meta.target;
3149 spin_unlock(&root->fs_info->balance_lock);
3154 spin_unlock(&root->fs_info->balance_lock);
3156 if (num_devices == 1)
3157 flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0);
3158 if (num_devices < 4)
3159 flags &= ~BTRFS_BLOCK_GROUP_RAID10;
3161 if ((flags & BTRFS_BLOCK_GROUP_DUP) &&
3162 (flags & (BTRFS_BLOCK_GROUP_RAID1 |
3163 BTRFS_BLOCK_GROUP_RAID10))) {
3164 flags &= ~BTRFS_BLOCK_GROUP_DUP;
3167 if ((flags & BTRFS_BLOCK_GROUP_RAID1) &&
3168 (flags & BTRFS_BLOCK_GROUP_RAID10)) {
3169 flags &= ~BTRFS_BLOCK_GROUP_RAID1;
3172 if ((flags & BTRFS_BLOCK_GROUP_RAID0) &&
3173 ((flags & BTRFS_BLOCK_GROUP_RAID1) |
3174 (flags & BTRFS_BLOCK_GROUP_RAID10) |
3175 (flags & BTRFS_BLOCK_GROUP_DUP))) {
3176 flags &= ~BTRFS_BLOCK_GROUP_RAID0;
3180 /* extended -> chunk profile */
3181 flags &= ~BTRFS_AVAIL_ALLOC_BIT_SINGLE;
3185 static u64 get_alloc_profile(struct btrfs_root *root, u64 flags)
3187 if (flags & BTRFS_BLOCK_GROUP_DATA)
3188 flags |= root->fs_info->avail_data_alloc_bits;
3189 else if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
3190 flags |= root->fs_info->avail_system_alloc_bits;
3191 else if (flags & BTRFS_BLOCK_GROUP_METADATA)
3192 flags |= root->fs_info->avail_metadata_alloc_bits;
3194 return btrfs_reduce_alloc_profile(root, flags);
3197 u64 btrfs_get_alloc_profile(struct btrfs_root *root, int data)
3202 flags = BTRFS_BLOCK_GROUP_DATA;
3203 else if (root == root->fs_info->chunk_root)
3204 flags = BTRFS_BLOCK_GROUP_SYSTEM;
3206 flags = BTRFS_BLOCK_GROUP_METADATA;
3208 return get_alloc_profile(root, flags);
3211 void btrfs_set_inode_space_info(struct btrfs_root *root, struct inode *inode)
3213 BTRFS_I(inode)->space_info = __find_space_info(root->fs_info,
3214 BTRFS_BLOCK_GROUP_DATA);
3218 * This will check the space that the inode allocates from to make sure we have
3219 * enough space for bytes.
3221 int btrfs_check_data_free_space(struct inode *inode, u64 bytes)
3223 struct btrfs_space_info *data_sinfo;
3224 struct btrfs_root *root = BTRFS_I(inode)->root;
3226 int ret = 0, committed = 0, alloc_chunk = 1;
3228 /* make sure bytes are sectorsize aligned */
3229 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3231 if (root == root->fs_info->tree_root ||
3232 BTRFS_I(inode)->location.objectid == BTRFS_FREE_INO_OBJECTID) {
3237 data_sinfo = BTRFS_I(inode)->space_info;
3242 /* make sure we have enough space to handle the data first */
3243 spin_lock(&data_sinfo->lock);
3244 used = data_sinfo->bytes_used + data_sinfo->bytes_reserved +
3245 data_sinfo->bytes_pinned + data_sinfo->bytes_readonly +
3246 data_sinfo->bytes_may_use;
3248 if (used + bytes > data_sinfo->total_bytes) {
3249 struct btrfs_trans_handle *trans;
3252 * if we don't have enough free bytes in this space then we need
3253 * to alloc a new chunk.
3255 if (!data_sinfo->full && alloc_chunk) {
3258 data_sinfo->force_alloc = CHUNK_ALLOC_FORCE;
3259 spin_unlock(&data_sinfo->lock);
3261 alloc_target = btrfs_get_alloc_profile(root, 1);
3262 trans = btrfs_join_transaction(root);
3264 return PTR_ERR(trans);
3266 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
3267 bytes + 2 * 1024 * 1024,
3269 CHUNK_ALLOC_NO_FORCE);
3270 btrfs_end_transaction(trans, root);
3279 btrfs_set_inode_space_info(root, inode);
3280 data_sinfo = BTRFS_I(inode)->space_info;
3286 * If we have less pinned bytes than we want to allocate then
3287 * don't bother committing the transaction, it won't help us.
3289 if (data_sinfo->bytes_pinned < bytes)
3291 spin_unlock(&data_sinfo->lock);
3293 /* commit the current transaction and try again */
3296 !atomic_read(&root->fs_info->open_ioctl_trans)) {
3298 trans = btrfs_join_transaction(root);
3300 return PTR_ERR(trans);
3301 ret = btrfs_commit_transaction(trans, root);
3309 data_sinfo->bytes_may_use += bytes;
3310 trace_btrfs_space_reservation(root->fs_info, "space_info",
3311 (u64)(unsigned long)data_sinfo,
3313 spin_unlock(&data_sinfo->lock);
3319 * Called if we need to clear a data reservation for this inode.
3321 void btrfs_free_reserved_data_space(struct inode *inode, u64 bytes)
3323 struct btrfs_root *root = BTRFS_I(inode)->root;
3324 struct btrfs_space_info *data_sinfo;
3326 /* make sure bytes are sectorsize aligned */
3327 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3329 data_sinfo = BTRFS_I(inode)->space_info;
3330 spin_lock(&data_sinfo->lock);
3331 data_sinfo->bytes_may_use -= bytes;
3332 trace_btrfs_space_reservation(root->fs_info, "space_info",
3333 (u64)(unsigned long)data_sinfo,
3335 spin_unlock(&data_sinfo->lock);
3338 static void force_metadata_allocation(struct btrfs_fs_info *info)
3340 struct list_head *head = &info->space_info;
3341 struct btrfs_space_info *found;
3344 list_for_each_entry_rcu(found, head, list) {
3345 if (found->flags & BTRFS_BLOCK_GROUP_METADATA)
3346 found->force_alloc = CHUNK_ALLOC_FORCE;
3351 static int should_alloc_chunk(struct btrfs_root *root,
3352 struct btrfs_space_info *sinfo, u64 alloc_bytes,
3355 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
3356 u64 num_bytes = sinfo->total_bytes - sinfo->bytes_readonly;
3357 u64 num_allocated = sinfo->bytes_used + sinfo->bytes_reserved;
3360 if (force == CHUNK_ALLOC_FORCE)
3364 * We need to take into account the global rsv because for all intents
3365 * and purposes it's used space. Don't worry about locking the
3366 * global_rsv, it doesn't change except when the transaction commits.
3368 num_allocated += global_rsv->size;
3371 * in limited mode, we want to have some free space up to
3372 * about 1% of the FS size.
3374 if (force == CHUNK_ALLOC_LIMITED) {
3375 thresh = btrfs_super_total_bytes(root->fs_info->super_copy);
3376 thresh = max_t(u64, 64 * 1024 * 1024,
3377 div_factor_fine(thresh, 1));
3379 if (num_bytes - num_allocated < thresh)
3382 thresh = btrfs_super_total_bytes(root->fs_info->super_copy);
3384 /* 256MB or 2% of the FS */
3385 thresh = max_t(u64, 256 * 1024 * 1024, div_factor_fine(thresh, 2));
3386 /* system chunks need a much small threshold */
3387 if (sinfo->flags & BTRFS_BLOCK_GROUP_SYSTEM)
3388 thresh = 32 * 1024 * 1024;
3390 if (num_bytes > thresh && sinfo->bytes_used < div_factor(num_bytes, 8))
3395 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
3396 struct btrfs_root *extent_root, u64 alloc_bytes,
3397 u64 flags, int force)
3399 struct btrfs_space_info *space_info;
3400 struct btrfs_fs_info *fs_info = extent_root->fs_info;
3401 int wait_for_alloc = 0;
3404 BUG_ON(!profile_is_valid(flags, 0));
3406 space_info = __find_space_info(extent_root->fs_info, flags);
3408 ret = update_space_info(extent_root->fs_info, flags,
3412 BUG_ON(!space_info);
3415 spin_lock(&space_info->lock);
3416 if (force < space_info->force_alloc)
3417 force = space_info->force_alloc;
3418 if (space_info->full) {
3419 spin_unlock(&space_info->lock);
3423 if (!should_alloc_chunk(extent_root, space_info, alloc_bytes, force)) {
3424 spin_unlock(&space_info->lock);
3426 } else if (space_info->chunk_alloc) {
3429 space_info->chunk_alloc = 1;
3432 spin_unlock(&space_info->lock);
3434 mutex_lock(&fs_info->chunk_mutex);
3437 * The chunk_mutex is held throughout the entirety of a chunk
3438 * allocation, so once we've acquired the chunk_mutex we know that the
3439 * other guy is done and we need to recheck and see if we should
3442 if (wait_for_alloc) {
3443 mutex_unlock(&fs_info->chunk_mutex);
3449 * If we have mixed data/metadata chunks we want to make sure we keep
3450 * allocating mixed chunks instead of individual chunks.
3452 if (btrfs_mixed_space_info(space_info))
3453 flags |= (BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA);
3456 * if we're doing a data chunk, go ahead and make sure that
3457 * we keep a reasonable number of metadata chunks allocated in the
3460 if (flags & BTRFS_BLOCK_GROUP_DATA && fs_info->metadata_ratio) {
3461 fs_info->data_chunk_allocations++;
3462 if (!(fs_info->data_chunk_allocations %
3463 fs_info->metadata_ratio))
3464 force_metadata_allocation(fs_info);
3467 ret = btrfs_alloc_chunk(trans, extent_root, flags);
3468 if (ret < 0 && ret != -ENOSPC)
3471 spin_lock(&space_info->lock);
3473 space_info->full = 1;
3477 space_info->force_alloc = CHUNK_ALLOC_NO_FORCE;
3478 space_info->chunk_alloc = 0;
3479 spin_unlock(&space_info->lock);
3481 mutex_unlock(&extent_root->fs_info->chunk_mutex);
3486 * shrink metadata reservation for delalloc
3488 static int shrink_delalloc(struct btrfs_root *root, u64 to_reclaim,
3491 struct btrfs_block_rsv *block_rsv;
3492 struct btrfs_space_info *space_info;
3493 struct btrfs_trans_handle *trans;
3498 unsigned long nr_pages = (2 * 1024 * 1024) >> PAGE_CACHE_SHIFT;
3500 unsigned long progress;
3502 trans = (struct btrfs_trans_handle *)current->journal_info;
3503 block_rsv = &root->fs_info->delalloc_block_rsv;
3504 space_info = block_rsv->space_info;
3507 reserved = space_info->bytes_may_use;
3508 progress = space_info->reservation_progress;
3514 if (root->fs_info->delalloc_bytes == 0) {
3517 btrfs_wait_ordered_extents(root, 0, 0);
3521 max_reclaim = min(reserved, to_reclaim);
3522 nr_pages = max_t(unsigned long, nr_pages,
3523 max_reclaim >> PAGE_CACHE_SHIFT);
3524 while (loops < 1024) {
3525 /* have the flusher threads jump in and do some IO */
3527 nr_pages = min_t(unsigned long, nr_pages,
3528 root->fs_info->delalloc_bytes >> PAGE_CACHE_SHIFT);
3529 writeback_inodes_sb_nr_if_idle(root->fs_info->sb, nr_pages,
3530 WB_REASON_FS_FREE_SPACE);
3532 spin_lock(&space_info->lock);
3533 if (reserved > space_info->bytes_may_use)
3534 reclaimed += reserved - space_info->bytes_may_use;
3535 reserved = space_info->bytes_may_use;
3536 spin_unlock(&space_info->lock);
3540 if (reserved == 0 || reclaimed >= max_reclaim)
3543 if (trans && trans->transaction->blocked)
3546 if (wait_ordered && !trans) {
3547 btrfs_wait_ordered_extents(root, 0, 0);
3549 time_left = schedule_timeout_interruptible(1);
3551 /* We were interrupted, exit */
3556 /* we've kicked the IO a few times, if anything has been freed,
3557 * exit. There is no sense in looping here for a long time
3558 * when we really need to commit the transaction, or there are
3559 * just too many writers without enough free space
3564 if (progress != space_info->reservation_progress)
3570 return reclaimed >= to_reclaim;
3574 * maybe_commit_transaction - possibly commit the transaction if its ok to
3575 * @root - the root we're allocating for
3576 * @bytes - the number of bytes we want to reserve
3577 * @force - force the commit
3579 * This will check to make sure that committing the transaction will actually
3580 * get us somewhere and then commit the transaction if it does. Otherwise it
3581 * will return -ENOSPC.
3583 static int may_commit_transaction(struct btrfs_root *root,
3584 struct btrfs_space_info *space_info,
3585 u64 bytes, int force)
3587 struct btrfs_block_rsv *delayed_rsv = &root->fs_info->delayed_block_rsv;
3588 struct btrfs_trans_handle *trans;
3590 trans = (struct btrfs_trans_handle *)current->journal_info;
3597 /* See if there is enough pinned space to make this reservation */
3598 spin_lock(&space_info->lock);
3599 if (space_info->bytes_pinned >= bytes) {
3600 spin_unlock(&space_info->lock);
3603 spin_unlock(&space_info->lock);
3606 * See if there is some space in the delayed insertion reservation for
3609 if (space_info != delayed_rsv->space_info)
3612 spin_lock(&space_info->lock);
3613 spin_lock(&delayed_rsv->lock);
3614 if (space_info->bytes_pinned + delayed_rsv->size < bytes) {
3615 spin_unlock(&delayed_rsv->lock);
3616 spin_unlock(&space_info->lock);
3619 spin_unlock(&delayed_rsv->lock);
3620 spin_unlock(&space_info->lock);
3623 trans = btrfs_join_transaction(root);
3627 return btrfs_commit_transaction(trans, root);
3631 * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
3632 * @root - the root we're allocating for
3633 * @block_rsv - the block_rsv we're allocating for
3634 * @orig_bytes - the number of bytes we want
3635 * @flush - wether or not we can flush to make our reservation
3637 * This will reserve orgi_bytes number of bytes from the space info associated
3638 * with the block_rsv. If there is not enough space it will make an attempt to
3639 * flush out space to make room. It will do this by flushing delalloc if
3640 * possible or committing the transaction. If flush is 0 then no attempts to
3641 * regain reservations will be made and this will fail if there is not enough
3644 static int reserve_metadata_bytes(struct btrfs_root *root,
3645 struct btrfs_block_rsv *block_rsv,
3646 u64 orig_bytes, int flush)
3648 struct btrfs_space_info *space_info = block_rsv->space_info;
3650 u64 num_bytes = orig_bytes;
3653 bool committed = false;
3654 bool flushing = false;
3655 bool wait_ordered = false;
3659 spin_lock(&space_info->lock);
3661 * We only want to wait if somebody other than us is flushing and we are
3662 * actually alloed to flush.
3664 while (flush && !flushing && space_info->flush) {
3665 spin_unlock(&space_info->lock);
3667 * If we have a trans handle we can't wait because the flusher
3668 * may have to commit the transaction, which would mean we would
3669 * deadlock since we are waiting for the flusher to finish, but
3670 * hold the current transaction open.
3672 if (current->journal_info)
3674 ret = wait_event_interruptible(space_info->wait,
3675 !space_info->flush);
3676 /* Must have been interrupted, return */
3680 spin_lock(&space_info->lock);
3684 used = space_info->bytes_used + space_info->bytes_reserved +
3685 space_info->bytes_pinned + space_info->bytes_readonly +
3686 space_info->bytes_may_use;
3689 * The idea here is that we've not already over-reserved the block group
3690 * then we can go ahead and save our reservation first and then start
3691 * flushing if we need to. Otherwise if we've already overcommitted
3692 * lets start flushing stuff first and then come back and try to make
3695 if (used <= space_info->total_bytes) {
3696 if (used + orig_bytes <= space_info->total_bytes) {
3697 space_info->bytes_may_use += orig_bytes;
3698 trace_btrfs_space_reservation(root->fs_info,
3700 (u64)(unsigned long)space_info,
3705 * Ok set num_bytes to orig_bytes since we aren't
3706 * overocmmitted, this way we only try and reclaim what
3709 num_bytes = orig_bytes;
3713 * Ok we're over committed, set num_bytes to the overcommitted
3714 * amount plus the amount of bytes that we need for this
3717 wait_ordered = true;
3718 num_bytes = used - space_info->total_bytes +
3719 (orig_bytes * (retries + 1));
3723 u64 profile = btrfs_get_alloc_profile(root, 0);
3727 * If we have a lot of space that's pinned, don't bother doing
3728 * the overcommit dance yet and just commit the transaction.
3730 avail = (space_info->total_bytes - space_info->bytes_used) * 8;
3732 if (space_info->bytes_pinned >= avail && flush && !committed) {
3733 space_info->flush = 1;
3735 spin_unlock(&space_info->lock);
3736 ret = may_commit_transaction(root, space_info,
3744 spin_lock(&root->fs_info->free_chunk_lock);
3745 avail = root->fs_info->free_chunk_space;
3748 * If we have dup, raid1 or raid10 then only half of the free
3749 * space is actually useable.
3751 if (profile & (BTRFS_BLOCK_GROUP_DUP |
3752 BTRFS_BLOCK_GROUP_RAID1 |
3753 BTRFS_BLOCK_GROUP_RAID10))
3757 * If we aren't flushing don't let us overcommit too much, say
3758 * 1/8th of the space. If we can flush, let it overcommit up to
3765 spin_unlock(&root->fs_info->free_chunk_lock);
3767 if (used + num_bytes < space_info->total_bytes + avail) {
3768 space_info->bytes_may_use += orig_bytes;
3769 trace_btrfs_space_reservation(root->fs_info,
3771 (u64)(unsigned long)space_info,
3775 wait_ordered = true;
3780 * Couldn't make our reservation, save our place so while we're trying
3781 * to reclaim space we can actually use it instead of somebody else
3782 * stealing it from us.
3786 space_info->flush = 1;
3789 spin_unlock(&space_info->lock);
3795 * We do synchronous shrinking since we don't actually unreserve
3796 * metadata until after the IO is completed.
3798 ret = shrink_delalloc(root, num_bytes, wait_ordered);
3805 * So if we were overcommitted it's possible that somebody else flushed
3806 * out enough space and we simply didn't have enough space to reclaim,
3807 * so go back around and try again.
3810 wait_ordered = true;
3819 ret = may_commit_transaction(root, space_info, orig_bytes, 0);
3827 spin_lock(&space_info->lock);
3828 space_info->flush = 0;
3829 wake_up_all(&space_info->wait);
3830 spin_unlock(&space_info->lock);
3835 static struct btrfs_block_rsv *get_block_rsv(struct btrfs_trans_handle *trans,
3836 struct btrfs_root *root)
3838 struct btrfs_block_rsv *block_rsv = NULL;
3840 if (root->ref_cows || root == root->fs_info->csum_root)
3841 block_rsv = trans->block_rsv;
3844 block_rsv = root->block_rsv;
3847 block_rsv = &root->fs_info->empty_block_rsv;
3852 static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
3856 spin_lock(&block_rsv->lock);
3857 if (block_rsv->reserved >= num_bytes) {
3858 block_rsv->reserved -= num_bytes;
3859 if (block_rsv->reserved < block_rsv->size)
3860 block_rsv->full = 0;
3863 spin_unlock(&block_rsv->lock);
3867 static void block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
3868 u64 num_bytes, int update_size)
3870 spin_lock(&block_rsv->lock);
3871 block_rsv->reserved += num_bytes;
3873 block_rsv->size += num_bytes;
3874 else if (block_rsv->reserved >= block_rsv->size)
3875 block_rsv->full = 1;
3876 spin_unlock(&block_rsv->lock);
3879 static void block_rsv_release_bytes(struct btrfs_fs_info *fs_info,
3880 struct btrfs_block_rsv *block_rsv,
3881 struct btrfs_block_rsv *dest, u64 num_bytes)
3883 struct btrfs_space_info *space_info = block_rsv->space_info;
3885 spin_lock(&block_rsv->lock);
3886 if (num_bytes == (u64)-1)
3887 num_bytes = block_rsv->size;
3888 block_rsv->size -= num_bytes;
3889 if (block_rsv->reserved >= block_rsv->size) {
3890 num_bytes = block_rsv->reserved - block_rsv->size;
3891 block_rsv->reserved = block_rsv->size;
3892 block_rsv->full = 1;
3896 spin_unlock(&block_rsv->lock);
3898 if (num_bytes > 0) {
3900 spin_lock(&dest->lock);
3904 bytes_to_add = dest->size - dest->reserved;
3905 bytes_to_add = min(num_bytes, bytes_to_add);
3906 dest->reserved += bytes_to_add;
3907 if (dest->reserved >= dest->size)
3909 num_bytes -= bytes_to_add;
3911 spin_unlock(&dest->lock);
3914 spin_lock(&space_info->lock);
3915 space_info->bytes_may_use -= num_bytes;
3916 trace_btrfs_space_reservation(fs_info, "space_info",
3917 (u64)(unsigned long)space_info,
3919 space_info->reservation_progress++;
3920 spin_unlock(&space_info->lock);
3925 static int block_rsv_migrate_bytes(struct btrfs_block_rsv *src,
3926 struct btrfs_block_rsv *dst, u64 num_bytes)
3930 ret = block_rsv_use_bytes(src, num_bytes);
3934 block_rsv_add_bytes(dst, num_bytes, 1);
3938 void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv)
3940 memset(rsv, 0, sizeof(*rsv));
3941 spin_lock_init(&rsv->lock);
3944 struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_root *root)
3946 struct btrfs_block_rsv *block_rsv;
3947 struct btrfs_fs_info *fs_info = root->fs_info;
3949 block_rsv = kmalloc(sizeof(*block_rsv), GFP_NOFS);
3953 btrfs_init_block_rsv(block_rsv);
3954 block_rsv->space_info = __find_space_info(fs_info,
3955 BTRFS_BLOCK_GROUP_METADATA);
3959 void btrfs_free_block_rsv(struct btrfs_root *root,
3960 struct btrfs_block_rsv *rsv)
3962 btrfs_block_rsv_release(root, rsv, (u64)-1);
3966 static inline int __block_rsv_add(struct btrfs_root *root,
3967 struct btrfs_block_rsv *block_rsv,
3968 u64 num_bytes, int flush)
3975 ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
3977 block_rsv_add_bytes(block_rsv, num_bytes, 1);
3984 int btrfs_block_rsv_add(struct btrfs_root *root,
3985 struct btrfs_block_rsv *block_rsv,
3988 return __block_rsv_add(root, block_rsv, num_bytes, 1);
3991 int btrfs_block_rsv_add_noflush(struct btrfs_root *root,
3992 struct btrfs_block_rsv *block_rsv,
3995 return __block_rsv_add(root, block_rsv, num_bytes, 0);
3998 int btrfs_block_rsv_check(struct btrfs_root *root,
3999 struct btrfs_block_rsv *block_rsv, int min_factor)
4007 spin_lock(&block_rsv->lock);
4008 num_bytes = div_factor(block_rsv->size, min_factor);
4009 if (block_rsv->reserved >= num_bytes)
4011 spin_unlock(&block_rsv->lock);
4016 static inline int __btrfs_block_rsv_refill(struct btrfs_root *root,
4017 struct btrfs_block_rsv *block_rsv,
4018 u64 min_reserved, int flush)
4026 spin_lock(&block_rsv->lock);
4027 num_bytes = min_reserved;
4028 if (block_rsv->reserved >= num_bytes)
4031 num_bytes -= block_rsv->reserved;
4032 spin_unlock(&block_rsv->lock);
4037 ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
4039 block_rsv_add_bytes(block_rsv, num_bytes, 0);
4046 int btrfs_block_rsv_refill(struct btrfs_root *root,
4047 struct btrfs_block_rsv *block_rsv,
4050 return __btrfs_block_rsv_refill(root, block_rsv, min_reserved, 1);
4053 int btrfs_block_rsv_refill_noflush(struct btrfs_root *root,
4054 struct btrfs_block_rsv *block_rsv,
4057 return __btrfs_block_rsv_refill(root, block_rsv, min_reserved, 0);
4060 int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,
4061 struct btrfs_block_rsv *dst_rsv,
4064 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
4067 void btrfs_block_rsv_release(struct btrfs_root *root,
4068 struct btrfs_block_rsv *block_rsv,
4071 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
4072 if (global_rsv->full || global_rsv == block_rsv ||
4073 block_rsv->space_info != global_rsv->space_info)
4075 block_rsv_release_bytes(root->fs_info, block_rsv, global_rsv,
4080 * helper to calculate size of global block reservation.
4081 * the desired value is sum of space used by extent tree,
4082 * checksum tree and root tree
4084 static u64 calc_global_metadata_size(struct btrfs_fs_info *fs_info)
4086 struct btrfs_space_info *sinfo;
4090 int csum_size = btrfs_super_csum_size(fs_info->super_copy);
4092 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_DATA);
4093 spin_lock(&sinfo->lock);
4094 data_used = sinfo->bytes_used;
4095 spin_unlock(&sinfo->lock);
4097 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
4098 spin_lock(&sinfo->lock);
4099 if (sinfo->flags & BTRFS_BLOCK_GROUP_DATA)
4101 meta_used = sinfo->bytes_used;
4102 spin_unlock(&sinfo->lock);
4104 num_bytes = (data_used >> fs_info->sb->s_blocksize_bits) *
4106 num_bytes += div64_u64(data_used + meta_used, 50);
4108 if (num_bytes * 3 > meta_used)
4109 num_bytes = div64_u64(meta_used, 3) * 2;
4111 return ALIGN(num_bytes, fs_info->extent_root->leafsize << 10);
4114 static void update_global_block_rsv(struct btrfs_fs_info *fs_info)
4116 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
4117 struct btrfs_space_info *sinfo = block_rsv->space_info;
4120 num_bytes = calc_global_metadata_size(fs_info);
4122 spin_lock(&block_rsv->lock);
4123 spin_lock(&sinfo->lock);
4125 block_rsv->size = num_bytes;
4127 num_bytes = sinfo->bytes_used + sinfo->bytes_pinned +
4128 sinfo->bytes_reserved + sinfo->bytes_readonly +
4129 sinfo->bytes_may_use;
4131 if (sinfo->total_bytes > num_bytes) {
4132 num_bytes = sinfo->total_bytes - num_bytes;
4133 block_rsv->reserved += num_bytes;
4134 sinfo->bytes_may_use += num_bytes;
4135 trace_btrfs_space_reservation(fs_info, "space_info",
4136 (u64)(unsigned long)sinfo, num_bytes, 1);
4139 if (block_rsv->reserved >= block_rsv->size) {
4140 num_bytes = block_rsv->reserved - block_rsv->size;
4141 sinfo->bytes_may_use -= num_bytes;
4142 trace_btrfs_space_reservation(fs_info, "space_info",
4143 (u64)(unsigned long)sinfo, num_bytes, 0);
4144 sinfo->reservation_progress++;
4145 block_rsv->reserved = block_rsv->size;
4146 block_rsv->full = 1;
4149 spin_unlock(&sinfo->lock);
4150 spin_unlock(&block_rsv->lock);
4153 static void init_global_block_rsv(struct btrfs_fs_info *fs_info)
4155 struct btrfs_space_info *space_info;
4157 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
4158 fs_info->chunk_block_rsv.space_info = space_info;
4160 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
4161 fs_info->global_block_rsv.space_info = space_info;
4162 fs_info->delalloc_block_rsv.space_info = space_info;
4163 fs_info->trans_block_rsv.space_info = space_info;
4164 fs_info->empty_block_rsv.space_info = space_info;
4165 fs_info->delayed_block_rsv.space_info = space_info;
4167 fs_info->extent_root->block_rsv = &fs_info->global_block_rsv;
4168 fs_info->csum_root->block_rsv = &fs_info->global_block_rsv;
4169 fs_info->dev_root->block_rsv = &fs_info->global_block_rsv;
4170 fs_info->tree_root->block_rsv = &fs_info->global_block_rsv;
4171 fs_info->chunk_root->block_rsv = &fs_info->chunk_block_rsv;
4173 update_global_block_rsv(fs_info);
4176 static void release_global_block_rsv(struct btrfs_fs_info *fs_info)
4178 block_rsv_release_bytes(fs_info, &fs_info->global_block_rsv, NULL,
4180 WARN_ON(fs_info->delalloc_block_rsv.size > 0);
4181 WARN_ON(fs_info->delalloc_block_rsv.reserved > 0);
4182 WARN_ON(fs_info->trans_block_rsv.size > 0);
4183 WARN_ON(fs_info->trans_block_rsv.reserved > 0);
4184 WARN_ON(fs_info->chunk_block_rsv.size > 0);
4185 WARN_ON(fs_info->chunk_block_rsv.reserved > 0);
4186 WARN_ON(fs_info->delayed_block_rsv.size > 0);
4187 WARN_ON(fs_info->delayed_block_rsv.reserved > 0);
4190 void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans,
4191 struct btrfs_root *root)
4193 if (!trans->bytes_reserved)
4196 trace_btrfs_space_reservation(root->fs_info, "transaction",
4197 (u64)(unsigned long)trans,
4198 trans->bytes_reserved, 0);
4199 btrfs_block_rsv_release(root, trans->block_rsv, trans->bytes_reserved);
4200 trans->bytes_reserved = 0;
4203 int btrfs_orphan_reserve_metadata(struct btrfs_trans_handle *trans,
4204 struct inode *inode)
4206 struct btrfs_root *root = BTRFS_I(inode)->root;
4207 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
4208 struct btrfs_block_rsv *dst_rsv = root->orphan_block_rsv;
4211 * We need to hold space in order to delete our orphan item once we've
4212 * added it, so this takes the reservation so we can release it later
4213 * when we are truly done with the orphan item.
4215 u64 num_bytes = btrfs_calc_trans_metadata_size(root, 1);
4216 trace_btrfs_space_reservation(root->fs_info, "orphan",
4217 btrfs_ino(inode), num_bytes, 1);
4218 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
4221 void btrfs_orphan_release_metadata(struct inode *inode)
4223 struct btrfs_root *root = BTRFS_I(inode)->root;
4224 u64 num_bytes = btrfs_calc_trans_metadata_size(root, 1);
4225 trace_btrfs_space_reservation(root->fs_info, "orphan",
4226 btrfs_ino(inode), num_bytes, 0);
4227 btrfs_block_rsv_release(root, root->orphan_block_rsv, num_bytes);
4230 int btrfs_snap_reserve_metadata(struct btrfs_trans_handle *trans,
4231 struct btrfs_pending_snapshot *pending)
4233 struct btrfs_root *root = pending->root;
4234 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
4235 struct btrfs_block_rsv *dst_rsv = &pending->block_rsv;
4237 * two for root back/forward refs, two for directory entries
4238 * and one for root of the snapshot.
4240 u64 num_bytes = btrfs_calc_trans_metadata_size(root, 5);
4241 dst_rsv->space_info = src_rsv->space_info;
4242 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
4246 * drop_outstanding_extent - drop an outstanding extent
4247 * @inode: the inode we're dropping the extent for
4249 * This is called when we are freeing up an outstanding extent, either called
4250 * after an error or after an extent is written. This will return the number of
4251 * reserved extents that need to be freed. This must be called with
4252 * BTRFS_I(inode)->lock held.
4254 static unsigned drop_outstanding_extent(struct inode *inode)
4256 unsigned drop_inode_space = 0;
4257 unsigned dropped_extents = 0;
4259 BUG_ON(!BTRFS_I(inode)->outstanding_extents);
4260 BTRFS_I(inode)->outstanding_extents--;
4262 if (BTRFS_I(inode)->outstanding_extents == 0 &&
4263 BTRFS_I(inode)->delalloc_meta_reserved) {
4264 drop_inode_space = 1;
4265 BTRFS_I(inode)->delalloc_meta_reserved = 0;
4269 * If we have more or the same amount of outsanding extents than we have
4270 * reserved then we need to leave the reserved extents count alone.
4272 if (BTRFS_I(inode)->outstanding_extents >=
4273 BTRFS_I(inode)->reserved_extents)
4274 return drop_inode_space;
4276 dropped_extents = BTRFS_I(inode)->reserved_extents -
4277 BTRFS_I(inode)->outstanding_extents;
4278 BTRFS_I(inode)->reserved_extents -= dropped_extents;
4279 return dropped_extents + drop_inode_space;
4283 * calc_csum_metadata_size - return the amount of metada space that must be
4284 * reserved/free'd for the given bytes.
4285 * @inode: the inode we're manipulating
4286 * @num_bytes: the number of bytes in question
4287 * @reserve: 1 if we are reserving space, 0 if we are freeing space
4289 * This adjusts the number of csum_bytes in the inode and then returns the
4290 * correct amount of metadata that must either be reserved or freed. We
4291 * calculate how many checksums we can fit into one leaf and then divide the
4292 * number of bytes that will need to be checksumed by this value to figure out
4293 * how many checksums will be required. If we are adding bytes then the number
4294 * may go up and we will return the number of additional bytes that must be
4295 * reserved. If it is going down we will return the number of bytes that must
4298 * This must be called with BTRFS_I(inode)->lock held.
4300 static u64 calc_csum_metadata_size(struct inode *inode, u64 num_bytes,
4303 struct btrfs_root *root = BTRFS_I(inode)->root;
4305 int num_csums_per_leaf;
4309 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM &&
4310 BTRFS_I(inode)->csum_bytes == 0)
4313 old_csums = (int)div64_u64(BTRFS_I(inode)->csum_bytes, root->sectorsize);
4315 BTRFS_I(inode)->csum_bytes += num_bytes;
4317 BTRFS_I(inode)->csum_bytes -= num_bytes;
4318 csum_size = BTRFS_LEAF_DATA_SIZE(root) - sizeof(struct btrfs_item);
4319 num_csums_per_leaf = (int)div64_u64(csum_size,
4320 sizeof(struct btrfs_csum_item) +
4321 sizeof(struct btrfs_disk_key));
4322 num_csums = (int)div64_u64(BTRFS_I(inode)->csum_bytes, root->sectorsize);
4323 num_csums = num_csums + num_csums_per_leaf - 1;
4324 num_csums = num_csums / num_csums_per_leaf;
4326 old_csums = old_csums + num_csums_per_leaf - 1;
4327 old_csums = old_csums / num_csums_per_leaf;
4329 /* No change, no need to reserve more */
4330 if (old_csums == num_csums)
4334 return btrfs_calc_trans_metadata_size(root,
4335 num_csums - old_csums);
4337 return btrfs_calc_trans_metadata_size(root, old_csums - num_csums);
4340 int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
4342 struct btrfs_root *root = BTRFS_I(inode)->root;
4343 struct btrfs_block_rsv *block_rsv = &root->fs_info->delalloc_block_rsv;
4346 unsigned nr_extents = 0;
4347 int extra_reserve = 0;
4351 /* Need to be holding the i_mutex here if we aren't free space cache */
4352 if (btrfs_is_free_space_inode(root, inode))
4355 if (flush && btrfs_transaction_in_commit(root->fs_info))
4356 schedule_timeout(1);
4358 mutex_lock(&BTRFS_I(inode)->delalloc_mutex);
4359 num_bytes = ALIGN(num_bytes, root->sectorsize);
4361 spin_lock(&BTRFS_I(inode)->lock);
4362 BTRFS_I(inode)->outstanding_extents++;
4364 if (BTRFS_I(inode)->outstanding_extents >
4365 BTRFS_I(inode)->reserved_extents)
4366 nr_extents = BTRFS_I(inode)->outstanding_extents -
4367 BTRFS_I(inode)->reserved_extents;
4370 * Add an item to reserve for updating the inode when we complete the
4373 if (!BTRFS_I(inode)->delalloc_meta_reserved) {
4378 to_reserve = btrfs_calc_trans_metadata_size(root, nr_extents);
4379 to_reserve += calc_csum_metadata_size(inode, num_bytes, 1);
4380 csum_bytes = BTRFS_I(inode)->csum_bytes;
4381 spin_unlock(&BTRFS_I(inode)->lock);
4383 ret = reserve_metadata_bytes(root, block_rsv, to_reserve, flush);
4388 spin_lock(&BTRFS_I(inode)->lock);
4389 dropped = drop_outstanding_extent(inode);
4391 * If the inodes csum_bytes is the same as the original
4392 * csum_bytes then we know we haven't raced with any free()ers
4393 * so we can just reduce our inodes csum bytes and carry on.
4394 * Otherwise we have to do the normal free thing to account for
4395 * the case that the free side didn't free up its reserve
4396 * because of this outstanding reservation.
4398 if (BTRFS_I(inode)->csum_bytes == csum_bytes)
4399 calc_csum_metadata_size(inode, num_bytes, 0);
4401 to_free = calc_csum_metadata_size(inode, num_bytes, 0);
4402 spin_unlock(&BTRFS_I(inode)->lock);
4404 to_free += btrfs_calc_trans_metadata_size(root, dropped);
4407 btrfs_block_rsv_release(root, block_rsv, to_free);
4408 trace_btrfs_space_reservation(root->fs_info,
4413 mutex_unlock(&BTRFS_I(inode)->delalloc_mutex);
4417 spin_lock(&BTRFS_I(inode)->lock);
4418 if (extra_reserve) {
4419 BTRFS_I(inode)->delalloc_meta_reserved = 1;
4422 BTRFS_I(inode)->reserved_extents += nr_extents;
4423 spin_unlock(&BTRFS_I(inode)->lock);
4424 mutex_unlock(&BTRFS_I(inode)->delalloc_mutex);
4427 trace_btrfs_space_reservation(root->fs_info,"delalloc",
4428 btrfs_ino(inode), to_reserve, 1);
4429 block_rsv_add_bytes(block_rsv, to_reserve, 1);
4435 * btrfs_delalloc_release_metadata - release a metadata reservation for an inode
4436 * @inode: the inode to release the reservation for
4437 * @num_bytes: the number of bytes we're releasing
4439 * This will release the metadata reservation for an inode. This can be called
4440 * once we complete IO for a given set of bytes to release their metadata
4443 void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes)
4445 struct btrfs_root *root = BTRFS_I(inode)->root;
4449 num_bytes = ALIGN(num_bytes, root->sectorsize);
4450 spin_lock(&BTRFS_I(inode)->lock);
4451 dropped = drop_outstanding_extent(inode);
4453 to_free = calc_csum_metadata_size(inode, num_bytes, 0);
4454 spin_unlock(&BTRFS_I(inode)->lock);
4456 to_free += btrfs_calc_trans_metadata_size(root, dropped);
4458 trace_btrfs_space_reservation(root->fs_info, "delalloc",
4459 btrfs_ino(inode), to_free, 0);
4460 btrfs_block_rsv_release(root, &root->fs_info->delalloc_block_rsv,
4465 * btrfs_delalloc_reserve_space - reserve data and metadata space for delalloc
4466 * @inode: inode we're writing to
4467 * @num_bytes: the number of bytes we want to allocate
4469 * This will do the following things
4471 * o reserve space in the data space info for num_bytes
4472 * o reserve space in the metadata space info based on number of outstanding
4473 * extents and how much csums will be needed
4474 * o add to the inodes ->delalloc_bytes
4475 * o add it to the fs_info's delalloc inodes list.
4477 * This will return 0 for success and -ENOSPC if there is no space left.
4479 int btrfs_delalloc_reserve_space(struct inode *inode, u64 num_bytes)
4483 ret = btrfs_check_data_free_space(inode, num_bytes);
4487 ret = btrfs_delalloc_reserve_metadata(inode, num_bytes);
4489 btrfs_free_reserved_data_space(inode, num_bytes);
4497 * btrfs_delalloc_release_space - release data and metadata space for delalloc
4498 * @inode: inode we're releasing space for
4499 * @num_bytes: the number of bytes we want to free up
4501 * This must be matched with a call to btrfs_delalloc_reserve_space. This is
4502 * called in the case that we don't need the metadata AND data reservations
4503 * anymore. So if there is an error or we insert an inline extent.
4505 * This function will release the metadata space that was not used and will
4506 * decrement ->delalloc_bytes and remove it from the fs_info delalloc_inodes
4507 * list if there are no delalloc bytes left.
4509 void btrfs_delalloc_release_space(struct inode *inode, u64 num_bytes)
4511 btrfs_delalloc_release_metadata(inode, num_bytes);
4512 btrfs_free_reserved_data_space(inode, num_bytes);
4515 static int update_block_group(struct btrfs_trans_handle *trans,
4516 struct btrfs_root *root,
4517 u64 bytenr, u64 num_bytes, int alloc)
4519 struct btrfs_block_group_cache *cache = NULL;
4520 struct btrfs_fs_info *info = root->fs_info;
4521 u64 total = num_bytes;
4526 /* block accounting for super block */
4527 spin_lock(&info->delalloc_lock);
4528 old_val = btrfs_super_bytes_used(info->super_copy);
4530 old_val += num_bytes;
4532 old_val -= num_bytes;
4533 btrfs_set_super_bytes_used(info->super_copy, old_val);
4534 spin_unlock(&info->delalloc_lock);
4537 cache = btrfs_lookup_block_group(info, bytenr);
4540 if (cache->flags & (BTRFS_BLOCK_GROUP_DUP |
4541 BTRFS_BLOCK_GROUP_RAID1 |
4542 BTRFS_BLOCK_GROUP_RAID10))
4547 * If this block group has free space cache written out, we
4548 * need to make sure to load it if we are removing space. This
4549 * is because we need the unpinning stage to actually add the
4550 * space back to the block group, otherwise we will leak space.
4552 if (!alloc && cache->cached == BTRFS_CACHE_NO)
4553 cache_block_group(cache, trans, NULL, 1);
4555 byte_in_group = bytenr - cache->key.objectid;
4556 WARN_ON(byte_in_group > cache->key.offset);
4558 spin_lock(&cache->space_info->lock);
4559 spin_lock(&cache->lock);
4561 if (btrfs_test_opt(root, SPACE_CACHE) &&
4562 cache->disk_cache_state < BTRFS_DC_CLEAR)
4563 cache->disk_cache_state = BTRFS_DC_CLEAR;
4566 old_val = btrfs_block_group_used(&cache->item);
4567 num_bytes = min(total, cache->key.offset - byte_in_group);
4569 old_val += num_bytes;
4570 btrfs_set_block_group_used(&cache->item, old_val);
4571 cache->reserved -= num_bytes;
4572 cache->space_info->bytes_reserved -= num_bytes;
4573 cache->space_info->bytes_used += num_bytes;
4574 cache->space_info->disk_used += num_bytes * factor;
4575 spin_unlock(&cache->lock);
4576 spin_unlock(&cache->space_info->lock);
4578 old_val -= num_bytes;
4579 btrfs_set_block_group_used(&cache->item, old_val);
4580 cache->pinned += num_bytes;
4581 cache->space_info->bytes_pinned += num_bytes;
4582 cache->space_info->bytes_used -= num_bytes;
4583 cache->space_info->disk_used -= num_bytes * factor;
4584 spin_unlock(&cache->lock);
4585 spin_unlock(&cache->space_info->lock);
4587 set_extent_dirty(info->pinned_extents,
4588 bytenr, bytenr + num_bytes - 1,
4589 GFP_NOFS | __GFP_NOFAIL);
4591 btrfs_put_block_group(cache);
4593 bytenr += num_bytes;
4598 static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
4600 struct btrfs_block_group_cache *cache;
4603 cache = btrfs_lookup_first_block_group(root->fs_info, search_start);
4607 bytenr = cache->key.objectid;
4608 btrfs_put_block_group(cache);
4613 static int pin_down_extent(struct btrfs_root *root,
4614 struct btrfs_block_group_cache *cache,
4615 u64 bytenr, u64 num_bytes, int reserved)
4617 spin_lock(&cache->space_info->lock);
4618 spin_lock(&cache->lock);
4619 cache->pinned += num_bytes;
4620 cache->space_info->bytes_pinned += num_bytes;
4622 cache->reserved -= num_bytes;
4623 cache->space_info->bytes_reserved -= num_bytes;
4625 spin_unlock(&cache->lock);
4626 spin_unlock(&cache->space_info->lock);
4628 set_extent_dirty(root->fs_info->pinned_extents, bytenr,
4629 bytenr + num_bytes - 1, GFP_NOFS | __GFP_NOFAIL);
4634 * this function must be called within transaction
4636 int btrfs_pin_extent(struct btrfs_root *root,
4637 u64 bytenr, u64 num_bytes, int reserved)
4639 struct btrfs_block_group_cache *cache;
4641 cache = btrfs_lookup_block_group(root->fs_info, bytenr);
4644 pin_down_extent(root, cache, bytenr, num_bytes, reserved);
4646 btrfs_put_block_group(cache);
4651 * this function must be called within transaction
4653 int btrfs_pin_extent_for_log_replay(struct btrfs_trans_handle *trans,
4654 struct btrfs_root *root,
4655 u64 bytenr, u64 num_bytes)
4657 struct btrfs_block_group_cache *cache;
4659 cache = btrfs_lookup_block_group(root->fs_info, bytenr);
4663 * pull in the free space cache (if any) so that our pin
4664 * removes the free space from the cache. We have load_only set
4665 * to one because the slow code to read in the free extents does check
4666 * the pinned extents.
4668 cache_block_group(cache, trans, root, 1);
4670 pin_down_extent(root, cache, bytenr, num_bytes, 0);
4672 /* remove us from the free space cache (if we're there at all) */
4673 btrfs_remove_free_space(cache, bytenr, num_bytes);
4674 btrfs_put_block_group(cache);
4679 * btrfs_update_reserved_bytes - update the block_group and space info counters
4680 * @cache: The cache we are manipulating
4681 * @num_bytes: The number of bytes in question
4682 * @reserve: One of the reservation enums
4684 * This is called by the allocator when it reserves space, or by somebody who is
4685 * freeing space that was never actually used on disk. For example if you
4686 * reserve some space for a new leaf in transaction A and before transaction A
4687 * commits you free that leaf, you call this with reserve set to 0 in order to
4688 * clear the reservation.
4690 * Metadata reservations should be called with RESERVE_ALLOC so we do the proper
4691 * ENOSPC accounting. For data we handle the reservation through clearing the
4692 * delalloc bits in the io_tree. We have to do this since we could end up
4693 * allocating less disk space for the amount of data we have reserved in the
4694 * case of compression.
4696 * If this is a reservation and the block group has become read only we cannot
4697 * make the reservation and return -EAGAIN, otherwise this function always
4700 static int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache,
4701 u64 num_bytes, int reserve)
4703 struct btrfs_space_info *space_info = cache->space_info;
4705 spin_lock(&space_info->lock);
4706 spin_lock(&cache->lock);
4707 if (reserve != RESERVE_FREE) {
4711 cache->reserved += num_bytes;
4712 space_info->bytes_reserved += num_bytes;
4713 if (reserve == RESERVE_ALLOC) {
4714 trace_btrfs_space_reservation(cache->fs_info,
4716 (u64)(unsigned long)space_info,
4718 space_info->bytes_may_use -= num_bytes;
4723 space_info->bytes_readonly += num_bytes;
4724 cache->reserved -= num_bytes;
4725 space_info->bytes_reserved -= num_bytes;
4726 space_info->reservation_progress++;
4728 spin_unlock(&cache->lock);
4729 spin_unlock(&space_info->lock);
4733 void btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
4734 struct btrfs_root *root)
4736 struct btrfs_fs_info *fs_info = root->fs_info;
4737 struct btrfs_caching_control *next;
4738 struct btrfs_caching_control *caching_ctl;
4739 struct btrfs_block_group_cache *cache;
4741 down_write(&fs_info->extent_commit_sem);
4743 list_for_each_entry_safe(caching_ctl, next,
4744 &fs_info->caching_block_groups, list) {
4745 cache = caching_ctl->block_group;
4746 if (block_group_cache_done(cache)) {
4747 cache->last_byte_to_unpin = (u64)-1;
4748 list_del_init(&caching_ctl->list);
4749 put_caching_control(caching_ctl);
4751 cache->last_byte_to_unpin = caching_ctl->progress;
4755 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
4756 fs_info->pinned_extents = &fs_info->freed_extents[1];
4758 fs_info->pinned_extents = &fs_info->freed_extents[0];
4760 up_write(&fs_info->extent_commit_sem);
4762 update_global_block_rsv(fs_info);
4765 static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
4767 struct btrfs_fs_info *fs_info = root->fs_info;
4768 struct btrfs_block_group_cache *cache = NULL;
4771 while (start <= end) {
4773 start >= cache->key.objectid + cache->key.offset) {
4775 btrfs_put_block_group(cache);
4776 cache = btrfs_lookup_block_group(fs_info, start);
4780 len = cache->key.objectid + cache->key.offset - start;
4781 len = min(len, end + 1 - start);
4783 if (start < cache->last_byte_to_unpin) {
4784 len = min(len, cache->last_byte_to_unpin - start);
4785 btrfs_add_free_space(cache, start, len);
4790 spin_lock(&cache->space_info->lock);
4791 spin_lock(&cache->lock);
4792 cache->pinned -= len;
4793 cache->space_info->bytes_pinned -= len;
4795 cache->space_info->bytes_readonly += len;
4796 spin_unlock(&cache->lock);
4797 spin_unlock(&cache->space_info->lock);
4801 btrfs_put_block_group(cache);
4805 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
4806 struct btrfs_root *root)
4808 struct btrfs_fs_info *fs_info = root->fs_info;
4809 struct extent_io_tree *unpin;
4814 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
4815 unpin = &fs_info->freed_extents[1];
4817 unpin = &fs_info->freed_extents[0];
4820 ret = find_first_extent_bit(unpin, 0, &start, &end,
4825 if (btrfs_test_opt(root, DISCARD))
4826 ret = btrfs_discard_extent(root, start,
4827 end + 1 - start, NULL);
4829 clear_extent_dirty(unpin, start, end, GFP_NOFS);
4830 unpin_extent_range(root, start, end);
4837 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
4838 struct btrfs_root *root,
4839 u64 bytenr, u64 num_bytes, u64 parent,
4840 u64 root_objectid, u64 owner_objectid,
4841 u64 owner_offset, int refs_to_drop,
4842 struct btrfs_delayed_extent_op *extent_op)
4844 struct btrfs_key key;
4845 struct btrfs_path *path;
4846 struct btrfs_fs_info *info = root->fs_info;
4847 struct btrfs_root *extent_root = info->extent_root;
4848 struct extent_buffer *leaf;
4849 struct btrfs_extent_item *ei;
4850 struct btrfs_extent_inline_ref *iref;
4853 int extent_slot = 0;
4854 int found_extent = 0;
4859 path = btrfs_alloc_path();
4864 path->leave_spinning = 1;
4866 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
4867 BUG_ON(!is_data && refs_to_drop != 1);
4869 ret = lookup_extent_backref(trans, extent_root, path, &iref,
4870 bytenr, num_bytes, parent,
4871 root_objectid, owner_objectid,
4874 extent_slot = path->slots[0];
4875 while (extent_slot >= 0) {
4876 btrfs_item_key_to_cpu(path->nodes[0], &key,
4878 if (key.objectid != bytenr)
4880 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
4881 key.offset == num_bytes) {
4885 if (path->slots[0] - extent_slot > 5)
4889 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
4890 item_size = btrfs_item_size_nr(path->nodes[0], extent_slot);
4891 if (found_extent && item_size < sizeof(*ei))
4894 if (!found_extent) {
4896 ret = remove_extent_backref(trans, extent_root, path,
4900 btrfs_release_path(path);
4901 path->leave_spinning = 1;
4903 key.objectid = bytenr;
4904 key.type = BTRFS_EXTENT_ITEM_KEY;
4905 key.offset = num_bytes;
4907 ret = btrfs_search_slot(trans, extent_root,
4910 printk(KERN_ERR "umm, got %d back from search"
4911 ", was looking for %llu\n", ret,
4912 (unsigned long long)bytenr);
4914 btrfs_print_leaf(extent_root,
4918 extent_slot = path->slots[0];
4921 btrfs_print_leaf(extent_root, path->nodes[0]);
4923 printk(KERN_ERR "btrfs unable to find ref byte nr %llu "
4924 "parent %llu root %llu owner %llu offset %llu\n",
4925 (unsigned long long)bytenr,
4926 (unsigned long long)parent,
4927 (unsigned long long)root_objectid,
4928 (unsigned long long)owner_objectid,
4929 (unsigned long long)owner_offset);
4932 leaf = path->nodes[0];
4933 item_size = btrfs_item_size_nr(leaf, extent_slot);
4934 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
4935 if (item_size < sizeof(*ei)) {
4936 BUG_ON(found_extent || extent_slot != path->slots[0]);
4937 ret = convert_extent_item_v0(trans, extent_root, path,
4941 btrfs_release_path(path);
4942 path->leave_spinning = 1;
4944 key.objectid = bytenr;
4945 key.type = BTRFS_EXTENT_ITEM_KEY;
4946 key.offset = num_bytes;
4948 ret = btrfs_search_slot(trans, extent_root, &key, path,
4951 printk(KERN_ERR "umm, got %d back from search"
4952 ", was looking for %llu\n", ret,
4953 (unsigned long long)bytenr);
4954 btrfs_print_leaf(extent_root, path->nodes[0]);
4957 extent_slot = path->slots[0];
4958 leaf = path->nodes[0];
4959 item_size = btrfs_item_size_nr(leaf, extent_slot);
4962 BUG_ON(item_size < sizeof(*ei));
4963 ei = btrfs_item_ptr(leaf, extent_slot,
4964 struct btrfs_extent_item);
4965 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID) {
4966 struct btrfs_tree_block_info *bi;
4967 BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
4968 bi = (struct btrfs_tree_block_info *)(ei + 1);
4969 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
4972 refs = btrfs_extent_refs(leaf, ei);
4973 BUG_ON(refs < refs_to_drop);
4974 refs -= refs_to_drop;
4978 __run_delayed_extent_op(extent_op, leaf, ei);
4980 * In the case of inline back ref, reference count will
4981 * be updated by remove_extent_backref
4984 BUG_ON(!found_extent);
4986 btrfs_set_extent_refs(leaf, ei, refs);
4987 btrfs_mark_buffer_dirty(leaf);
4990 ret = remove_extent_backref(trans, extent_root, path,
4997 BUG_ON(is_data && refs_to_drop !=
4998 extent_data_ref_count(root, path, iref));
5000 BUG_ON(path->slots[0] != extent_slot);
5002 BUG_ON(path->slots[0] != extent_slot + 1);
5003 path->slots[0] = extent_slot;
5008 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
5011 btrfs_release_path(path);
5014 ret = btrfs_del_csums(trans, root, bytenr, num_bytes);
5017 invalidate_mapping_pages(info->btree_inode->i_mapping,
5018 bytenr >> PAGE_CACHE_SHIFT,
5019 (bytenr + num_bytes - 1) >> PAGE_CACHE_SHIFT);
5022 ret = update_block_group(trans, root, bytenr, num_bytes, 0);
5025 btrfs_free_path(path);
5030 * when we free an block, it is possible (and likely) that we free the last
5031 * delayed ref for that extent as well. This searches the delayed ref tree for
5032 * a given extent, and if there are no other delayed refs to be processed, it
5033 * removes it from the tree.
5035 static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans,
5036 struct btrfs_root *root, u64 bytenr)
5038 struct btrfs_delayed_ref_head *head;
5039 struct btrfs_delayed_ref_root *delayed_refs;
5040 struct btrfs_delayed_ref_node *ref;
5041 struct rb_node *node;
5044 delayed_refs = &trans->transaction->delayed_refs;
5045 spin_lock(&delayed_refs->lock);
5046 head = btrfs_find_delayed_ref_head(trans, bytenr);
5050 node = rb_prev(&head->node.rb_node);
5054 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
5056 /* there are still entries for this ref, we can't drop it */
5057 if (ref->bytenr == bytenr)
5060 if (head->extent_op) {
5061 if (!head->must_insert_reserved)
5063 kfree(head->extent_op);
5064 head->extent_op = NULL;
5068 * waiting for the lock here would deadlock. If someone else has it
5069 * locked they are already in the process of dropping it anyway
5071 if (!mutex_trylock(&head->mutex))
5075 * at this point we have a head with no other entries. Go
5076 * ahead and process it.
5078 head->node.in_tree = 0;
5079 rb_erase(&head->node.rb_node, &delayed_refs->root);
5081 delayed_refs->num_entries--;
5082 if (waitqueue_active(&delayed_refs->seq_wait))
5083 wake_up(&delayed_refs->seq_wait);
5086 * we don't take a ref on the node because we're removing it from the
5087 * tree, so we just steal the ref the tree was holding.
5089 delayed_refs->num_heads--;
5090 if (list_empty(&head->cluster))
5091 delayed_refs->num_heads_ready--;
5093 list_del_init(&head->cluster);
5094 spin_unlock(&delayed_refs->lock);
5096 BUG_ON(head->extent_op);
5097 if (head->must_insert_reserved)
5100 mutex_unlock(&head->mutex);
5101 btrfs_put_delayed_ref(&head->node);
5104 spin_unlock(&delayed_refs->lock);
5108 void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
5109 struct btrfs_root *root,
5110 struct extent_buffer *buf,
5111 u64 parent, int last_ref, int for_cow)
5113 struct btrfs_block_group_cache *cache = NULL;
5116 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
5117 ret = btrfs_add_delayed_tree_ref(root->fs_info, trans,
5118 buf->start, buf->len,
5119 parent, root->root_key.objectid,
5120 btrfs_header_level(buf),
5121 BTRFS_DROP_DELAYED_REF, NULL, for_cow);
5128 cache = btrfs_lookup_block_group(root->fs_info, buf->start);
5130 if (btrfs_header_generation(buf) == trans->transid) {
5131 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
5132 ret = check_ref_cleanup(trans, root, buf->start);
5137 if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
5138 pin_down_extent(root, cache, buf->start, buf->len, 1);
5142 WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags));
5144 btrfs_add_free_space(cache, buf->start, buf->len);
5145 btrfs_update_reserved_bytes(cache, buf->len, RESERVE_FREE);
5149 * Deleting the buffer, clear the corrupt flag since it doesn't matter
5152 clear_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags);
5153 btrfs_put_block_group(cache);
5156 int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root *root,
5157 u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid,
5158 u64 owner, u64 offset, int for_cow)
5161 struct btrfs_fs_info *fs_info = root->fs_info;
5164 * tree log blocks never actually go into the extent allocation
5165 * tree, just update pinning info and exit early.
5167 if (root_objectid == BTRFS_TREE_LOG_OBJECTID) {
5168 WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID);
5169 /* unlocks the pinned mutex */
5170 btrfs_pin_extent(root, bytenr, num_bytes, 1);
5172 } else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
5173 ret = btrfs_add_delayed_tree_ref(fs_info, trans, bytenr,
5175 parent, root_objectid, (int)owner,
5176 BTRFS_DROP_DELAYED_REF, NULL, for_cow);
5179 ret = btrfs_add_delayed_data_ref(fs_info, trans, bytenr,
5181 parent, root_objectid, owner,
5182 offset, BTRFS_DROP_DELAYED_REF,
5189 static u64 stripe_align(struct btrfs_root *root, u64 val)
5191 u64 mask = ((u64)root->stripesize - 1);
5192 u64 ret = (val + mask) & ~mask;
5197 * when we wait for progress in the block group caching, its because
5198 * our allocation attempt failed at least once. So, we must sleep
5199 * and let some progress happen before we try again.
5201 * This function will sleep at least once waiting for new free space to
5202 * show up, and then it will check the block group free space numbers
5203 * for our min num_bytes. Another option is to have it go ahead
5204 * and look in the rbtree for a free extent of a given size, but this
5208 wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
5211 struct btrfs_caching_control *caching_ctl;
5214 caching_ctl = get_caching_control(cache);
5218 wait_event(caching_ctl->wait, block_group_cache_done(cache) ||
5219 (cache->free_space_ctl->free_space >= num_bytes));
5221 put_caching_control(caching_ctl);
5226 wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
5228 struct btrfs_caching_control *caching_ctl;
5231 caching_ctl = get_caching_control(cache);
5235 wait_event(caching_ctl->wait, block_group_cache_done(cache));
5237 put_caching_control(caching_ctl);
5241 static int get_block_group_index(struct btrfs_block_group_cache *cache)
5244 if (cache->flags & BTRFS_BLOCK_GROUP_RAID10)
5246 else if (cache->flags & BTRFS_BLOCK_GROUP_RAID1)
5248 else if (cache->flags & BTRFS_BLOCK_GROUP_DUP)
5250 else if (cache->flags & BTRFS_BLOCK_GROUP_RAID0)
5257 enum btrfs_loop_type {
5258 LOOP_FIND_IDEAL = 0,
5259 LOOP_CACHING_NOWAIT = 1,
5260 LOOP_CACHING_WAIT = 2,
5261 LOOP_ALLOC_CHUNK = 3,
5262 LOOP_NO_EMPTY_SIZE = 4,
5266 * walks the btree of allocated extents and find a hole of a given size.
5267 * The key ins is changed to record the hole:
5268 * ins->objectid == block start
5269 * ins->flags = BTRFS_EXTENT_ITEM_KEY
5270 * ins->offset == number of blocks
5271 * Any available blocks before search_start are skipped.
5273 static noinline int find_free_extent(struct btrfs_trans_handle *trans,
5274 struct btrfs_root *orig_root,
5275 u64 num_bytes, u64 empty_size,
5276 u64 search_start, u64 search_end,
5277 u64 hint_byte, struct btrfs_key *ins,
5281 struct btrfs_root *root = orig_root->fs_info->extent_root;
5282 struct btrfs_free_cluster *last_ptr = NULL;
5283 struct btrfs_block_group_cache *block_group = NULL;
5284 struct btrfs_block_group_cache *used_block_group;
5285 int empty_cluster = 2 * 1024 * 1024;
5286 int allowed_chunk_alloc = 0;
5287 int done_chunk_alloc = 0;
5288 struct btrfs_space_info *space_info;
5291 int alloc_type = (data & BTRFS_BLOCK_GROUP_DATA) ?
5292 RESERVE_ALLOC_NO_ACCOUNT : RESERVE_ALLOC;
5293 bool found_uncached_bg = false;
5294 bool failed_cluster_refill = false;
5295 bool failed_alloc = false;
5296 bool use_cluster = true;
5297 bool have_caching_bg = false;
5298 u64 ideal_cache_percent = 0;
5299 u64 ideal_cache_offset = 0;
5301 WARN_ON(num_bytes < root->sectorsize);
5302 btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
5306 trace_find_free_extent(orig_root, num_bytes, empty_size, data);
5308 space_info = __find_space_info(root->fs_info, data);
5310 printk(KERN_ERR "No space info for %llu\n", data);
5315 * If the space info is for both data and metadata it means we have a
5316 * small filesystem and we can't use the clustering stuff.
5318 if (btrfs_mixed_space_info(space_info))
5319 use_cluster = false;
5321 if (orig_root->ref_cows || empty_size)
5322 allowed_chunk_alloc = 1;
5324 if (data & BTRFS_BLOCK_GROUP_METADATA && use_cluster) {
5325 last_ptr = &root->fs_info->meta_alloc_cluster;
5326 if (!btrfs_test_opt(root, SSD))
5327 empty_cluster = 64 * 1024;
5330 if ((data & BTRFS_BLOCK_GROUP_DATA) && use_cluster &&
5331 btrfs_test_opt(root, SSD)) {
5332 last_ptr = &root->fs_info->data_alloc_cluster;
5336 spin_lock(&last_ptr->lock);
5337 if (last_ptr->block_group)
5338 hint_byte = last_ptr->window_start;
5339 spin_unlock(&last_ptr->lock);
5342 search_start = max(search_start, first_logical_byte(root, 0));
5343 search_start = max(search_start, hint_byte);
5348 if (search_start == hint_byte) {
5350 block_group = btrfs_lookup_block_group(root->fs_info,
5352 used_block_group = block_group;
5354 * we don't want to use the block group if it doesn't match our
5355 * allocation bits, or if its not cached.
5357 * However if we are re-searching with an ideal block group
5358 * picked out then we don't care that the block group is cached.
5360 if (block_group && block_group_bits(block_group, data) &&
5361 (block_group->cached != BTRFS_CACHE_NO ||
5362 search_start == ideal_cache_offset)) {
5363 down_read(&space_info->groups_sem);
5364 if (list_empty(&block_group->list) ||
5367 * someone is removing this block group,
5368 * we can't jump into the have_block_group
5369 * target because our list pointers are not
5372 btrfs_put_block_group(block_group);
5373 up_read(&space_info->groups_sem);
5375 index = get_block_group_index(block_group);
5376 goto have_block_group;
5378 } else if (block_group) {
5379 btrfs_put_block_group(block_group);
5383 have_caching_bg = false;
5384 down_read(&space_info->groups_sem);
5385 list_for_each_entry(block_group, &space_info->block_groups[index],
5390 used_block_group = block_group;
5391 btrfs_get_block_group(block_group);
5392 search_start = block_group->key.objectid;
5395 * this can happen if we end up cycling through all the
5396 * raid types, but we want to make sure we only allocate
5397 * for the proper type.
5399 if (!block_group_bits(block_group, data)) {
5400 u64 extra = BTRFS_BLOCK_GROUP_DUP |
5401 BTRFS_BLOCK_GROUP_RAID1 |
5402 BTRFS_BLOCK_GROUP_RAID10;
5405 * if they asked for extra copies and this block group
5406 * doesn't provide them, bail. This does allow us to
5407 * fill raid0 from raid1.
5409 if ((data & extra) && !(block_group->flags & extra))
5414 cached = block_group_cache_done(block_group);
5415 if (unlikely(!cached)) {
5418 found_uncached_bg = true;
5419 ret = cache_block_group(block_group, trans,
5421 if (block_group->cached == BTRFS_CACHE_FINISHED)
5424 free_percent = btrfs_block_group_used(&block_group->item);
5425 free_percent *= 100;
5426 free_percent = div64_u64(free_percent,
5427 block_group->key.offset);
5428 free_percent = 100 - free_percent;
5429 if (free_percent > ideal_cache_percent &&
5430 likely(!block_group->ro)) {
5431 ideal_cache_offset = block_group->key.objectid;
5432 ideal_cache_percent = free_percent;
5436 * The caching workers are limited to 2 threads, so we
5437 * can queue as much work as we care to.
5439 if (loop > LOOP_FIND_IDEAL) {
5440 ret = cache_block_group(block_group, trans,
5446 * If loop is set for cached only, try the next block
5449 if (loop == LOOP_FIND_IDEAL)
5454 if (unlikely(block_group->ro))
5458 * Ok we want to try and use the cluster allocator, so
5463 * the refill lock keeps out other
5464 * people trying to start a new cluster
5466 spin_lock(&last_ptr->refill_lock);
5467 used_block_group = last_ptr->block_group;
5468 if (used_block_group != block_group &&
5469 (!used_block_group ||
5470 used_block_group->ro ||
5471 !block_group_bits(used_block_group, data))) {
5472 used_block_group = block_group;
5473 goto refill_cluster;
5476 if (used_block_group != block_group)
5477 btrfs_get_block_group(used_block_group);
5479 offset = btrfs_alloc_from_cluster(used_block_group,
5480 last_ptr, num_bytes, used_block_group->key.objectid);
5482 /* we have a block, we're done */
5483 spin_unlock(&last_ptr->refill_lock);
5484 trace_btrfs_reserve_extent_cluster(root,
5485 block_group, search_start, num_bytes);
5489 WARN_ON(last_ptr->block_group != used_block_group);
5490 if (used_block_group != block_group) {
5491 btrfs_put_block_group(used_block_group);
5492 used_block_group = block_group;
5495 BUG_ON(used_block_group != block_group);
5496 /* If we are on LOOP_NO_EMPTY_SIZE, we can't
5497 * set up a new clusters, so lets just skip it
5498 * and let the allocator find whatever block
5499 * it can find. If we reach this point, we
5500 * will have tried the cluster allocator
5501 * plenty of times and not have found
5502 * anything, so we are likely way too
5503 * fragmented for the clustering stuff to find
5506 * However, if the cluster is taken from the
5507 * current block group, release the cluster
5508 * first, so that we stand a better chance of
5509 * succeeding in the unclustered
5511 if (loop >= LOOP_NO_EMPTY_SIZE &&
5512 last_ptr->block_group != block_group) {
5513 spin_unlock(&last_ptr->refill_lock);
5514 goto unclustered_alloc;
5518 * this cluster didn't work out, free it and
5521 btrfs_return_cluster_to_free_space(NULL, last_ptr);
5523 if (loop >= LOOP_NO_EMPTY_SIZE) {
5524 spin_unlock(&last_ptr->refill_lock);
5525 goto unclustered_alloc;
5528 /* allocate a cluster in this block group */
5529 ret = btrfs_find_space_cluster(trans, root,
5530 block_group, last_ptr,
5531 search_start, num_bytes,
5532 empty_cluster + empty_size);
5535 * now pull our allocation out of this
5538 offset = btrfs_alloc_from_cluster(block_group,
5539 last_ptr, num_bytes,
5542 /* we found one, proceed */
5543 spin_unlock(&last_ptr->refill_lock);
5544 trace_btrfs_reserve_extent_cluster(root,
5545 block_group, search_start,
5549 } else if (!cached && loop > LOOP_CACHING_NOWAIT
5550 && !failed_cluster_refill) {
5551 spin_unlock(&last_ptr->refill_lock);
5553 failed_cluster_refill = true;
5554 wait_block_group_cache_progress(block_group,
5555 num_bytes + empty_cluster + empty_size);
5556 goto have_block_group;
5560 * at this point we either didn't find a cluster
5561 * or we weren't able to allocate a block from our
5562 * cluster. Free the cluster we've been trying
5563 * to use, and go to the next block group
5565 btrfs_return_cluster_to_free_space(NULL, last_ptr);
5566 spin_unlock(&last_ptr->refill_lock);
5571 spin_lock(&block_group->free_space_ctl->tree_lock);
5573 block_group->free_space_ctl->free_space <
5574 num_bytes + empty_cluster + empty_size) {
5575 spin_unlock(&block_group->free_space_ctl->tree_lock);
5578 spin_unlock(&block_group->free_space_ctl->tree_lock);
5580 offset = btrfs_find_space_for_alloc(block_group, search_start,
5581 num_bytes, empty_size);
5583 * If we didn't find a chunk, and we haven't failed on this
5584 * block group before, and this block group is in the middle of
5585 * caching and we are ok with waiting, then go ahead and wait
5586 * for progress to be made, and set failed_alloc to true.
5588 * If failed_alloc is true then we've already waited on this
5589 * block group once and should move on to the next block group.
5591 if (!offset && !failed_alloc && !cached &&
5592 loop > LOOP_CACHING_NOWAIT) {
5593 wait_block_group_cache_progress(block_group,
5594 num_bytes + empty_size);
5595 failed_alloc = true;
5596 goto have_block_group;
5597 } else if (!offset) {
5599 have_caching_bg = true;
5603 search_start = stripe_align(root, offset);
5604 /* move on to the next group */
5605 if (search_start + num_bytes >= search_end) {
5606 btrfs_add_free_space(used_block_group, offset, num_bytes);
5610 /* move on to the next group */
5611 if (search_start + num_bytes >
5612 used_block_group->key.objectid + used_block_group->key.offset) {
5613 btrfs_add_free_space(used_block_group, offset, num_bytes);
5617 if (offset < search_start)
5618 btrfs_add_free_space(used_block_group, offset,
5619 search_start - offset);
5620 BUG_ON(offset > search_start);
5622 ret = btrfs_update_reserved_bytes(used_block_group, num_bytes,
5624 if (ret == -EAGAIN) {
5625 btrfs_add_free_space(used_block_group, offset, num_bytes);
5629 /* we are all good, lets return */
5630 ins->objectid = search_start;
5631 ins->offset = num_bytes;
5633 trace_btrfs_reserve_extent(orig_root, block_group,
5634 search_start, num_bytes);
5635 if (offset < search_start)
5636 btrfs_add_free_space(used_block_group, offset,
5637 search_start - offset);
5638 BUG_ON(offset > search_start);
5639 if (used_block_group != block_group)
5640 btrfs_put_block_group(used_block_group);
5641 btrfs_put_block_group(block_group);
5644 failed_cluster_refill = false;
5645 failed_alloc = false;
5646 BUG_ON(index != get_block_group_index(block_group));
5647 if (used_block_group != block_group)
5648 btrfs_put_block_group(used_block_group);
5649 btrfs_put_block_group(block_group);
5651 up_read(&space_info->groups_sem);
5653 if (!ins->objectid && loop >= LOOP_CACHING_WAIT && have_caching_bg)
5656 if (!ins->objectid && ++index < BTRFS_NR_RAID_TYPES)
5659 /* LOOP_FIND_IDEAL, only search caching/cached bg's, and don't wait for
5660 * for them to make caching progress. Also
5661 * determine the best possible bg to cache
5662 * LOOP_CACHING_NOWAIT, search partially cached block groups, kicking
5663 * caching kthreads as we move along
5664 * LOOP_CACHING_WAIT, search everything, and wait if our bg is caching
5665 * LOOP_ALLOC_CHUNK, force a chunk allocation and try again
5666 * LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try
5669 if (!ins->objectid && loop < LOOP_NO_EMPTY_SIZE) {
5671 if (loop == LOOP_FIND_IDEAL && found_uncached_bg) {
5672 found_uncached_bg = false;
5674 if (!ideal_cache_percent)
5678 * 1 of the following 2 things have happened so far
5680 * 1) We found an ideal block group for caching that
5681 * is mostly full and will cache quickly, so we might
5682 * as well wait for it.
5684 * 2) We searched for cached only and we didn't find
5685 * anything, and we didn't start any caching kthreads
5686 * either, so chances are we will loop through and
5687 * start a couple caching kthreads, and then come back
5688 * around and just wait for them. This will be slower
5689 * because we will have 2 caching kthreads reading at
5690 * the same time when we could have just started one
5691 * and waited for it to get far enough to give us an
5692 * allocation, so go ahead and go to the wait caching
5695 loop = LOOP_CACHING_WAIT;
5696 search_start = ideal_cache_offset;
5697 ideal_cache_percent = 0;
5699 } else if (loop == LOOP_FIND_IDEAL) {
5701 * Didn't find a uncached bg, wait on anything we find
5704 loop = LOOP_CACHING_WAIT;
5710 if (loop == LOOP_ALLOC_CHUNK) {
5711 if (allowed_chunk_alloc) {
5712 ret = do_chunk_alloc(trans, root, num_bytes +
5713 2 * 1024 * 1024, data,
5714 CHUNK_ALLOC_LIMITED);
5715 allowed_chunk_alloc = 0;
5717 done_chunk_alloc = 1;
5718 } else if (!done_chunk_alloc &&
5719 space_info->force_alloc ==
5720 CHUNK_ALLOC_NO_FORCE) {
5721 space_info->force_alloc = CHUNK_ALLOC_LIMITED;
5725 * We didn't allocate a chunk, go ahead and drop the
5726 * empty size and loop again.
5728 if (!done_chunk_alloc)
5729 loop = LOOP_NO_EMPTY_SIZE;
5732 if (loop == LOOP_NO_EMPTY_SIZE) {
5738 } else if (!ins->objectid) {
5740 } else if (ins->objectid) {
5747 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
5748 int dump_block_groups)
5750 struct btrfs_block_group_cache *cache;
5753 spin_lock(&info->lock);
5754 printk(KERN_INFO "space_info %llu has %llu free, is %sfull\n",
5755 (unsigned long long)info->flags,
5756 (unsigned long long)(info->total_bytes - info->bytes_used -
5757 info->bytes_pinned - info->bytes_reserved -
5758 info->bytes_readonly),
5759 (info->full) ? "" : "not ");
5760 printk(KERN_INFO "space_info total=%llu, used=%llu, pinned=%llu, "
5761 "reserved=%llu, may_use=%llu, readonly=%llu\n",
5762 (unsigned long long)info->total_bytes,
5763 (unsigned long long)info->bytes_used,
5764 (unsigned long long)info->bytes_pinned,
5765 (unsigned long long)info->bytes_reserved,
5766 (unsigned long long)info->bytes_may_use,
5767 (unsigned long long)info->bytes_readonly);
5768 spin_unlock(&info->lock);
5770 if (!dump_block_groups)
5773 down_read(&info->groups_sem);
5775 list_for_each_entry(cache, &info->block_groups[index], list) {
5776 spin_lock(&cache->lock);
5777 printk(KERN_INFO "block group %llu has %llu bytes, %llu used "
5778 "%llu pinned %llu reserved\n",
5779 (unsigned long long)cache->key.objectid,
5780 (unsigned long long)cache->key.offset,
5781 (unsigned long long)btrfs_block_group_used(&cache->item),
5782 (unsigned long long)cache->pinned,
5783 (unsigned long long)cache->reserved);
5784 btrfs_dump_free_space(cache, bytes);
5785 spin_unlock(&cache->lock);
5787 if (++index < BTRFS_NR_RAID_TYPES)
5789 up_read(&info->groups_sem);
5792 int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
5793 struct btrfs_root *root,
5794 u64 num_bytes, u64 min_alloc_size,
5795 u64 empty_size, u64 hint_byte,
5796 u64 search_end, struct btrfs_key *ins,
5799 bool final_tried = false;
5801 u64 search_start = 0;
5803 data = btrfs_get_alloc_profile(root, data);
5806 * the only place that sets empty_size is btrfs_realloc_node, which
5807 * is not called recursively on allocations
5809 if (empty_size || root->ref_cows)
5810 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
5811 num_bytes + 2 * 1024 * 1024, data,
5812 CHUNK_ALLOC_NO_FORCE);
5814 WARN_ON(num_bytes < root->sectorsize);
5815 ret = find_free_extent(trans, root, num_bytes, empty_size,
5816 search_start, search_end, hint_byte,
5819 if (ret == -ENOSPC) {
5821 num_bytes = num_bytes >> 1;
5822 num_bytes = num_bytes & ~(root->sectorsize - 1);
5823 num_bytes = max(num_bytes, min_alloc_size);
5824 do_chunk_alloc(trans, root->fs_info->extent_root,
5825 num_bytes, data, CHUNK_ALLOC_FORCE);
5826 if (num_bytes == min_alloc_size)
5829 } else if (btrfs_test_opt(root, ENOSPC_DEBUG)) {
5830 struct btrfs_space_info *sinfo;
5832 sinfo = __find_space_info(root->fs_info, data);
5833 printk(KERN_ERR "btrfs allocation failed flags %llu, "
5834 "wanted %llu\n", (unsigned long long)data,
5835 (unsigned long long)num_bytes);
5837 dump_space_info(sinfo, num_bytes, 1);
5841 trace_btrfs_reserved_extent_alloc(root, ins->objectid, ins->offset);
5846 static int __btrfs_free_reserved_extent(struct btrfs_root *root,
5847 u64 start, u64 len, int pin)
5849 struct btrfs_block_group_cache *cache;
5852 cache = btrfs_lookup_block_group(root->fs_info, start);
5854 printk(KERN_ERR "Unable to find block group for %llu\n",
5855 (unsigned long long)start);
5859 if (btrfs_test_opt(root, DISCARD))
5860 ret = btrfs_discard_extent(root, start, len, NULL);
5863 pin_down_extent(root, cache, start, len, 1);
5865 btrfs_add_free_space(cache, start, len);
5866 btrfs_update_reserved_bytes(cache, len, RESERVE_FREE);
5868 btrfs_put_block_group(cache);
5870 trace_btrfs_reserved_extent_free(root, start, len);
5875 int btrfs_free_reserved_extent(struct btrfs_root *root,
5878 return __btrfs_free_reserved_extent(root, start, len, 0);
5881 int btrfs_free_and_pin_reserved_extent(struct btrfs_root *root,
5884 return __btrfs_free_reserved_extent(root, start, len, 1);
5887 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
5888 struct btrfs_root *root,
5889 u64 parent, u64 root_objectid,
5890 u64 flags, u64 owner, u64 offset,
5891 struct btrfs_key *ins, int ref_mod)
5894 struct btrfs_fs_info *fs_info = root->fs_info;
5895 struct btrfs_extent_item *extent_item;
5896 struct btrfs_extent_inline_ref *iref;
5897 struct btrfs_path *path;
5898 struct extent_buffer *leaf;
5903 type = BTRFS_SHARED_DATA_REF_KEY;
5905 type = BTRFS_EXTENT_DATA_REF_KEY;
5907 size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type);
5909 path = btrfs_alloc_path();
5913 path->leave_spinning = 1;
5914 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
5918 leaf = path->nodes[0];
5919 extent_item = btrfs_item_ptr(leaf, path->slots[0],
5920 struct btrfs_extent_item);
5921 btrfs_set_extent_refs(leaf, extent_item, ref_mod);
5922 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
5923 btrfs_set_extent_flags(leaf, extent_item,
5924 flags | BTRFS_EXTENT_FLAG_DATA);
5926 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
5927 btrfs_set_extent_inline_ref_type(leaf, iref, type);
5929 struct btrfs_shared_data_ref *ref;
5930 ref = (struct btrfs_shared_data_ref *)(iref + 1);
5931 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
5932 btrfs_set_shared_data_ref_count(leaf, ref, ref_mod);
5934 struct btrfs_extent_data_ref *ref;
5935 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
5936 btrfs_set_extent_data_ref_root(leaf, ref, root_objectid);
5937 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
5938 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
5939 btrfs_set_extent_data_ref_count(leaf, ref, ref_mod);
5942 btrfs_mark_buffer_dirty(path->nodes[0]);
5943 btrfs_free_path(path);
5945 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
5947 printk(KERN_ERR "btrfs update block group failed for %llu "
5948 "%llu\n", (unsigned long long)ins->objectid,
5949 (unsigned long long)ins->offset);
5955 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
5956 struct btrfs_root *root,
5957 u64 parent, u64 root_objectid,
5958 u64 flags, struct btrfs_disk_key *key,
5959 int level, struct btrfs_key *ins)
5962 struct btrfs_fs_info *fs_info = root->fs_info;
5963 struct btrfs_extent_item *extent_item;
5964 struct btrfs_tree_block_info *block_info;
5965 struct btrfs_extent_inline_ref *iref;
5966 struct btrfs_path *path;
5967 struct extent_buffer *leaf;
5968 u32 size = sizeof(*extent_item) + sizeof(*block_info) + sizeof(*iref);
5970 path = btrfs_alloc_path();
5974 path->leave_spinning = 1;
5975 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
5979 leaf = path->nodes[0];
5980 extent_item = btrfs_item_ptr(leaf, path->slots[0],
5981 struct btrfs_extent_item);
5982 btrfs_set_extent_refs(leaf, extent_item, 1);
5983 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
5984 btrfs_set_extent_flags(leaf, extent_item,
5985 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
5986 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
5988 btrfs_set_tree_block_key(leaf, block_info, key);
5989 btrfs_set_tree_block_level(leaf, block_info, level);
5991 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
5993 BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF));
5994 btrfs_set_extent_inline_ref_type(leaf, iref,
5995 BTRFS_SHARED_BLOCK_REF_KEY);
5996 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
5998 btrfs_set_extent_inline_ref_type(leaf, iref,
5999 BTRFS_TREE_BLOCK_REF_KEY);
6000 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
6003 btrfs_mark_buffer_dirty(leaf);
6004 btrfs_free_path(path);
6006 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
6008 printk(KERN_ERR "btrfs update block group failed for %llu "
6009 "%llu\n", (unsigned long long)ins->objectid,
6010 (unsigned long long)ins->offset);
6016 int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
6017 struct btrfs_root *root,
6018 u64 root_objectid, u64 owner,
6019 u64 offset, struct btrfs_key *ins)
6023 BUG_ON(root_objectid == BTRFS_TREE_LOG_OBJECTID);
6025 ret = btrfs_add_delayed_data_ref(root->fs_info, trans, ins->objectid,
6027 root_objectid, owner, offset,
6028 BTRFS_ADD_DELAYED_EXTENT, NULL, 0);
6033 * this is used by the tree logging recovery code. It records that
6034 * an extent has been allocated and makes sure to clear the free
6035 * space cache bits as well
6037 int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
6038 struct btrfs_root *root,
6039 u64 root_objectid, u64 owner, u64 offset,
6040 struct btrfs_key *ins)
6043 struct btrfs_block_group_cache *block_group;
6044 struct btrfs_caching_control *caching_ctl;
6045 u64 start = ins->objectid;
6046 u64 num_bytes = ins->offset;
6048 block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
6049 cache_block_group(block_group, trans, NULL, 0);
6050 caching_ctl = get_caching_control(block_group);
6053 BUG_ON(!block_group_cache_done(block_group));
6054 ret = btrfs_remove_free_space(block_group, start, num_bytes);
6057 mutex_lock(&caching_ctl->mutex);
6059 if (start >= caching_ctl->progress) {
6060 ret = add_excluded_extent(root, start, num_bytes);
6062 } else if (start + num_bytes <= caching_ctl->progress) {
6063 ret = btrfs_remove_free_space(block_group,
6067 num_bytes = caching_ctl->progress - start;
6068 ret = btrfs_remove_free_space(block_group,
6072 start = caching_ctl->progress;
6073 num_bytes = ins->objectid + ins->offset -
6074 caching_ctl->progress;
6075 ret = add_excluded_extent(root, start, num_bytes);
6079 mutex_unlock(&caching_ctl->mutex);
6080 put_caching_control(caching_ctl);
6083 ret = btrfs_update_reserved_bytes(block_group, ins->offset,
6084 RESERVE_ALLOC_NO_ACCOUNT);
6086 btrfs_put_block_group(block_group);
6087 ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,
6088 0, owner, offset, ins, 1);
6092 struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
6093 struct btrfs_root *root,
6094 u64 bytenr, u32 blocksize,
6097 struct extent_buffer *buf;
6099 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
6101 return ERR_PTR(-ENOMEM);
6102 btrfs_set_header_generation(buf, trans->transid);
6103 btrfs_set_buffer_lockdep_class(root->root_key.objectid, buf, level);
6104 btrfs_tree_lock(buf);
6105 clean_tree_block(trans, root, buf);
6107 btrfs_set_lock_blocking(buf);
6108 btrfs_set_buffer_uptodate(buf);
6110 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
6112 * we allow two log transactions at a time, use different
6113 * EXENT bit to differentiate dirty pages.
6115 if (root->log_transid % 2 == 0)
6116 set_extent_dirty(&root->dirty_log_pages, buf->start,
6117 buf->start + buf->len - 1, GFP_NOFS);
6119 set_extent_new(&root->dirty_log_pages, buf->start,
6120 buf->start + buf->len - 1, GFP_NOFS);
6122 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
6123 buf->start + buf->len - 1, GFP_NOFS);
6125 trans->blocks_used++;
6126 /* this returns a buffer locked for blocking */
6130 static struct btrfs_block_rsv *
6131 use_block_rsv(struct btrfs_trans_handle *trans,
6132 struct btrfs_root *root, u32 blocksize)
6134 struct btrfs_block_rsv *block_rsv;
6135 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
6138 block_rsv = get_block_rsv(trans, root);
6140 if (block_rsv->size == 0) {
6141 ret = reserve_metadata_bytes(root, block_rsv, blocksize, 0);
6143 * If we couldn't reserve metadata bytes try and use some from
6144 * the global reserve.
6146 if (ret && block_rsv != global_rsv) {
6147 ret = block_rsv_use_bytes(global_rsv, blocksize);
6150 return ERR_PTR(ret);
6152 return ERR_PTR(ret);
6157 ret = block_rsv_use_bytes(block_rsv, blocksize);
6161 static DEFINE_RATELIMIT_STATE(_rs,
6162 DEFAULT_RATELIMIT_INTERVAL,
6163 /*DEFAULT_RATELIMIT_BURST*/ 2);
6164 if (__ratelimit(&_rs)) {
6165 printk(KERN_DEBUG "btrfs: block rsv returned %d\n", ret);
6168 ret = reserve_metadata_bytes(root, block_rsv, blocksize, 0);
6171 } else if (ret && block_rsv != global_rsv) {
6172 ret = block_rsv_use_bytes(global_rsv, blocksize);
6178 return ERR_PTR(-ENOSPC);
6181 static void unuse_block_rsv(struct btrfs_fs_info *fs_info,
6182 struct btrfs_block_rsv *block_rsv, u32 blocksize)
6184 block_rsv_add_bytes(block_rsv, blocksize, 0);
6185 block_rsv_release_bytes(fs_info, block_rsv, NULL, 0);
6189 * finds a free extent and does all the dirty work required for allocation
6190 * returns the key for the extent through ins, and a tree buffer for
6191 * the first block of the extent through buf.
6193 * returns the tree buffer or NULL.
6195 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
6196 struct btrfs_root *root, u32 blocksize,
6197 u64 parent, u64 root_objectid,
6198 struct btrfs_disk_key *key, int level,
6199 u64 hint, u64 empty_size, int for_cow)
6201 struct btrfs_key ins;
6202 struct btrfs_block_rsv *block_rsv;
6203 struct extent_buffer *buf;
6208 block_rsv = use_block_rsv(trans, root, blocksize);
6209 if (IS_ERR(block_rsv))
6210 return ERR_CAST(block_rsv);
6212 ret = btrfs_reserve_extent(trans, root, blocksize, blocksize,
6213 empty_size, hint, (u64)-1, &ins, 0);
6215 unuse_block_rsv(root->fs_info, block_rsv, blocksize);
6216 return ERR_PTR(ret);
6219 buf = btrfs_init_new_buffer(trans, root, ins.objectid,
6221 BUG_ON(IS_ERR(buf));
6223 if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
6225 parent = ins.objectid;
6226 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
6230 if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
6231 struct btrfs_delayed_extent_op *extent_op;
6232 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
6235 memcpy(&extent_op->key, key, sizeof(extent_op->key));
6237 memset(&extent_op->key, 0, sizeof(extent_op->key));
6238 extent_op->flags_to_set = flags;
6239 extent_op->update_key = 1;
6240 extent_op->update_flags = 1;
6241 extent_op->is_data = 0;
6243 ret = btrfs_add_delayed_tree_ref(root->fs_info, trans,
6245 ins.offset, parent, root_objectid,
6246 level, BTRFS_ADD_DELAYED_EXTENT,
6247 extent_op, for_cow);
6253 struct walk_control {
6254 u64 refs[BTRFS_MAX_LEVEL];
6255 u64 flags[BTRFS_MAX_LEVEL];
6256 struct btrfs_key update_progress;
6267 #define DROP_REFERENCE 1
6268 #define UPDATE_BACKREF 2
6270 static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
6271 struct btrfs_root *root,
6272 struct walk_control *wc,
6273 struct btrfs_path *path)
6281 struct btrfs_key key;
6282 struct extent_buffer *eb;
6287 if (path->slots[wc->level] < wc->reada_slot) {
6288 wc->reada_count = wc->reada_count * 2 / 3;
6289 wc->reada_count = max(wc->reada_count, 2);
6291 wc->reada_count = wc->reada_count * 3 / 2;
6292 wc->reada_count = min_t(int, wc->reada_count,
6293 BTRFS_NODEPTRS_PER_BLOCK(root));
6296 eb = path->nodes[wc->level];
6297 nritems = btrfs_header_nritems(eb);
6298 blocksize = btrfs_level_size(root, wc->level - 1);
6300 for (slot = path->slots[wc->level]; slot < nritems; slot++) {
6301 if (nread >= wc->reada_count)
6305 bytenr = btrfs_node_blockptr(eb, slot);
6306 generation = btrfs_node_ptr_generation(eb, slot);
6308 if (slot == path->slots[wc->level])
6311 if (wc->stage == UPDATE_BACKREF &&
6312 generation <= root->root_key.offset)
6315 /* We don't lock the tree block, it's OK to be racy here */
6316 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
6321 if (wc->stage == DROP_REFERENCE) {
6325 if (wc->level == 1 &&
6326 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
6328 if (!wc->update_ref ||
6329 generation <= root->root_key.offset)
6331 btrfs_node_key_to_cpu(eb, &key, slot);
6332 ret = btrfs_comp_cpu_keys(&key,
6333 &wc->update_progress);
6337 if (wc->level == 1 &&
6338 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
6342 ret = readahead_tree_block(root, bytenr, blocksize,
6348 wc->reada_slot = slot;
6352 * hepler to process tree block while walking down the tree.
6354 * when wc->stage == UPDATE_BACKREF, this function updates
6355 * back refs for pointers in the block.
6357 * NOTE: return value 1 means we should stop walking down.
6359 static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
6360 struct btrfs_root *root,
6361 struct btrfs_path *path,
6362 struct walk_control *wc, int lookup_info)
6364 int level = wc->level;
6365 struct extent_buffer *eb = path->nodes[level];
6366 u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF;
6369 if (wc->stage == UPDATE_BACKREF &&
6370 btrfs_header_owner(eb) != root->root_key.objectid)
6374 * when reference count of tree block is 1, it won't increase
6375 * again. once full backref flag is set, we never clear it.
6378 ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
6379 (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag)))) {
6380 BUG_ON(!path->locks[level]);
6381 ret = btrfs_lookup_extent_info(trans, root,
6386 BUG_ON(wc->refs[level] == 0);
6389 if (wc->stage == DROP_REFERENCE) {
6390 if (wc->refs[level] > 1)
6393 if (path->locks[level] && !wc->keep_locks) {
6394 btrfs_tree_unlock_rw(eb, path->locks[level]);
6395 path->locks[level] = 0;
6400 /* wc->stage == UPDATE_BACKREF */
6401 if (!(wc->flags[level] & flag)) {
6402 BUG_ON(!path->locks[level]);
6403 ret = btrfs_inc_ref(trans, root, eb, 1, wc->for_reloc);
6405 ret = btrfs_dec_ref(trans, root, eb, 0, wc->for_reloc);
6407 ret = btrfs_set_disk_extent_flags(trans, root, eb->start,
6410 wc->flags[level] |= flag;
6414 * the block is shared by multiple trees, so it's not good to
6415 * keep the tree lock
6417 if (path->locks[level] && level > 0) {
6418 btrfs_tree_unlock_rw(eb, path->locks[level]);
6419 path->locks[level] = 0;
6425 * hepler to process tree block pointer.
6427 * when wc->stage == DROP_REFERENCE, this function checks
6428 * reference count of the block pointed to. if the block
6429 * is shared and we need update back refs for the subtree
6430 * rooted at the block, this function changes wc->stage to
6431 * UPDATE_BACKREF. if the block is shared and there is no
6432 * need to update back, this function drops the reference
6435 * NOTE: return value 1 means we should stop walking down.
6437 static noinline int do_walk_down(struct btrfs_trans_handle *trans,
6438 struct btrfs_root *root,
6439 struct btrfs_path *path,
6440 struct walk_control *wc, int *lookup_info)
6446 struct btrfs_key key;
6447 struct extent_buffer *next;
6448 int level = wc->level;
6452 generation = btrfs_node_ptr_generation(path->nodes[level],
6453 path->slots[level]);
6455 * if the lower level block was created before the snapshot
6456 * was created, we know there is no need to update back refs
6459 if (wc->stage == UPDATE_BACKREF &&
6460 generation <= root->root_key.offset) {
6465 bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]);
6466 blocksize = btrfs_level_size(root, level - 1);
6468 next = btrfs_find_tree_block(root, bytenr, blocksize);
6470 next = btrfs_find_create_tree_block(root, bytenr, blocksize);
6475 btrfs_tree_lock(next);
6476 btrfs_set_lock_blocking(next);
6478 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
6479 &wc->refs[level - 1],
6480 &wc->flags[level - 1]);
6482 BUG_ON(wc->refs[level - 1] == 0);
6485 if (wc->stage == DROP_REFERENCE) {
6486 if (wc->refs[level - 1] > 1) {
6488 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
6491 if (!wc->update_ref ||
6492 generation <= root->root_key.offset)
6495 btrfs_node_key_to_cpu(path->nodes[level], &key,
6496 path->slots[level]);
6497 ret = btrfs_comp_cpu_keys(&key, &wc->update_progress);
6501 wc->stage = UPDATE_BACKREF;
6502 wc->shared_level = level - 1;
6506 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
6510 if (!btrfs_buffer_uptodate(next, generation)) {
6511 btrfs_tree_unlock(next);
6512 free_extent_buffer(next);
6518 if (reada && level == 1)
6519 reada_walk_down(trans, root, wc, path);
6520 next = read_tree_block(root, bytenr, blocksize, generation);
6523 btrfs_tree_lock(next);
6524 btrfs_set_lock_blocking(next);
6528 BUG_ON(level != btrfs_header_level(next));
6529 path->nodes[level] = next;
6530 path->slots[level] = 0;
6531 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6537 wc->refs[level - 1] = 0;
6538 wc->flags[level - 1] = 0;
6539 if (wc->stage == DROP_REFERENCE) {
6540 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
6541 parent = path->nodes[level]->start;
6543 BUG_ON(root->root_key.objectid !=
6544 btrfs_header_owner(path->nodes[level]));
6548 ret = btrfs_free_extent(trans, root, bytenr, blocksize, parent,
6549 root->root_key.objectid, level - 1, 0, 0);
6552 btrfs_tree_unlock(next);
6553 free_extent_buffer(next);
6559 * hepler to process tree block while walking up the tree.
6561 * when wc->stage == DROP_REFERENCE, this function drops
6562 * reference count on the block.
6564 * when wc->stage == UPDATE_BACKREF, this function changes
6565 * wc->stage back to DROP_REFERENCE if we changed wc->stage
6566 * to UPDATE_BACKREF previously while processing the block.
6568 * NOTE: return value 1 means we should stop walking up.
6570 static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
6571 struct btrfs_root *root,
6572 struct btrfs_path *path,
6573 struct walk_control *wc)
6576 int level = wc->level;
6577 struct extent_buffer *eb = path->nodes[level];
6580 if (wc->stage == UPDATE_BACKREF) {
6581 BUG_ON(wc->shared_level < level);
6582 if (level < wc->shared_level)
6585 ret = find_next_key(path, level + 1, &wc->update_progress);
6589 wc->stage = DROP_REFERENCE;
6590 wc->shared_level = -1;
6591 path->slots[level] = 0;
6594 * check reference count again if the block isn't locked.
6595 * we should start walking down the tree again if reference
6598 if (!path->locks[level]) {
6600 btrfs_tree_lock(eb);
6601 btrfs_set_lock_blocking(eb);
6602 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6604 ret = btrfs_lookup_extent_info(trans, root,
6609 BUG_ON(wc->refs[level] == 0);
6610 if (wc->refs[level] == 1) {
6611 btrfs_tree_unlock_rw(eb, path->locks[level]);
6617 /* wc->stage == DROP_REFERENCE */
6618 BUG_ON(wc->refs[level] > 1 && !path->locks[level]);
6620 if (wc->refs[level] == 1) {
6622 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6623 ret = btrfs_dec_ref(trans, root, eb, 1,
6626 ret = btrfs_dec_ref(trans, root, eb, 0,
6630 /* make block locked assertion in clean_tree_block happy */
6631 if (!path->locks[level] &&
6632 btrfs_header_generation(eb) == trans->transid) {
6633 btrfs_tree_lock(eb);
6634 btrfs_set_lock_blocking(eb);
6635 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6637 clean_tree_block(trans, root, eb);
6640 if (eb == root->node) {
6641 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6644 BUG_ON(root->root_key.objectid !=
6645 btrfs_header_owner(eb));
6647 if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6648 parent = path->nodes[level + 1]->start;
6650 BUG_ON(root->root_key.objectid !=
6651 btrfs_header_owner(path->nodes[level + 1]));
6654 btrfs_free_tree_block(trans, root, eb, parent, wc->refs[level] == 1, 0);
6656 wc->refs[level] = 0;
6657 wc->flags[level] = 0;
6661 static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
6662 struct btrfs_root *root,
6663 struct btrfs_path *path,
6664 struct walk_control *wc)
6666 int level = wc->level;
6667 int lookup_info = 1;
6670 while (level >= 0) {
6671 ret = walk_down_proc(trans, root, path, wc, lookup_info);
6678 if (path->slots[level] >=
6679 btrfs_header_nritems(path->nodes[level]))
6682 ret = do_walk_down(trans, root, path, wc, &lookup_info);
6684 path->slots[level]++;
6693 static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
6694 struct btrfs_root *root,
6695 struct btrfs_path *path,
6696 struct walk_control *wc, int max_level)
6698 int level = wc->level;
6701 path->slots[level] = btrfs_header_nritems(path->nodes[level]);
6702 while (level < max_level && path->nodes[level]) {
6704 if (path->slots[level] + 1 <
6705 btrfs_header_nritems(path->nodes[level])) {
6706 path->slots[level]++;
6709 ret = walk_up_proc(trans, root, path, wc);
6713 if (path->locks[level]) {
6714 btrfs_tree_unlock_rw(path->nodes[level],
6715 path->locks[level]);
6716 path->locks[level] = 0;
6718 free_extent_buffer(path->nodes[level]);
6719 path->nodes[level] = NULL;
6727 * drop a subvolume tree.
6729 * this function traverses the tree freeing any blocks that only
6730 * referenced by the tree.
6732 * when a shared tree block is found. this function decreases its
6733 * reference count by one. if update_ref is true, this function
6734 * also make sure backrefs for the shared block and all lower level
6735 * blocks are properly updated.
6737 void btrfs_drop_snapshot(struct btrfs_root *root,
6738 struct btrfs_block_rsv *block_rsv, int update_ref,
6741 struct btrfs_path *path;
6742 struct btrfs_trans_handle *trans;
6743 struct btrfs_root *tree_root = root->fs_info->tree_root;
6744 struct btrfs_root_item *root_item = &root->root_item;
6745 struct walk_control *wc;
6746 struct btrfs_key key;
6751 path = btrfs_alloc_path();
6757 wc = kzalloc(sizeof(*wc), GFP_NOFS);
6759 btrfs_free_path(path);
6764 trans = btrfs_start_transaction(tree_root, 0);
6765 BUG_ON(IS_ERR(trans));
6768 trans->block_rsv = block_rsv;
6770 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
6771 level = btrfs_header_level(root->node);
6772 path->nodes[level] = btrfs_lock_root_node(root);
6773 btrfs_set_lock_blocking(path->nodes[level]);
6774 path->slots[level] = 0;
6775 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6776 memset(&wc->update_progress, 0,
6777 sizeof(wc->update_progress));
6779 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
6780 memcpy(&wc->update_progress, &key,
6781 sizeof(wc->update_progress));
6783 level = root_item->drop_level;
6785 path->lowest_level = level;
6786 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6787 path->lowest_level = 0;
6795 * unlock our path, this is safe because only this
6796 * function is allowed to delete this snapshot
6798 btrfs_unlock_up_safe(path, 0);
6800 level = btrfs_header_level(root->node);
6802 btrfs_tree_lock(path->nodes[level]);
6803 btrfs_set_lock_blocking(path->nodes[level]);
6805 ret = btrfs_lookup_extent_info(trans, root,
6806 path->nodes[level]->start,
6807 path->nodes[level]->len,
6811 BUG_ON(wc->refs[level] == 0);
6813 if (level == root_item->drop_level)
6816 btrfs_tree_unlock(path->nodes[level]);
6817 WARN_ON(wc->refs[level] != 1);
6823 wc->shared_level = -1;
6824 wc->stage = DROP_REFERENCE;
6825 wc->update_ref = update_ref;
6827 wc->for_reloc = for_reloc;
6828 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
6831 ret = walk_down_tree(trans, root, path, wc);
6837 ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL);
6844 BUG_ON(wc->stage != DROP_REFERENCE);
6848 if (wc->stage == DROP_REFERENCE) {
6850 btrfs_node_key(path->nodes[level],
6851 &root_item->drop_progress,
6852 path->slots[level]);
6853 root_item->drop_level = level;
6856 BUG_ON(wc->level == 0);
6857 if (btrfs_should_end_transaction(trans, tree_root)) {
6858 ret = btrfs_update_root(trans, tree_root,
6863 btrfs_end_transaction_throttle(trans, tree_root);
6864 trans = btrfs_start_transaction(tree_root, 0);
6865 BUG_ON(IS_ERR(trans));
6867 trans->block_rsv = block_rsv;
6870 btrfs_release_path(path);
6873 ret = btrfs_del_root(trans, tree_root, &root->root_key);
6876 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
6877 ret = btrfs_find_last_root(tree_root, root->root_key.objectid,
6881 /* if we fail to delete the orphan item this time
6882 * around, it'll get picked up the next time.
6884 * The most common failure here is just -ENOENT.
6886 btrfs_del_orphan_item(trans, tree_root,
6887 root->root_key.objectid);
6891 if (root->in_radix) {
6892 btrfs_free_fs_root(tree_root->fs_info, root);
6894 free_extent_buffer(root->node);
6895 free_extent_buffer(root->commit_root);
6899 btrfs_end_transaction_throttle(trans, tree_root);
6901 btrfs_free_path(path);
6904 btrfs_std_error(root->fs_info, err);
6909 * drop subtree rooted at tree block 'node'.
6911 * NOTE: this function will unlock and release tree block 'node'
6912 * only used by relocation code
6914 int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
6915 struct btrfs_root *root,
6916 struct extent_buffer *node,
6917 struct extent_buffer *parent)
6919 struct btrfs_path *path;
6920 struct walk_control *wc;
6926 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
6928 path = btrfs_alloc_path();
6932 wc = kzalloc(sizeof(*wc), GFP_NOFS);
6934 btrfs_free_path(path);
6938 btrfs_assert_tree_locked(parent);
6939 parent_level = btrfs_header_level(parent);
6940 extent_buffer_get(parent);
6941 path->nodes[parent_level] = parent;
6942 path->slots[parent_level] = btrfs_header_nritems(parent);
6944 btrfs_assert_tree_locked(node);
6945 level = btrfs_header_level(node);
6946 path->nodes[level] = node;
6947 path->slots[level] = 0;
6948 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6950 wc->refs[parent_level] = 1;
6951 wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF;
6953 wc->shared_level = -1;
6954 wc->stage = DROP_REFERENCE;
6958 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
6961 wret = walk_down_tree(trans, root, path, wc);
6967 wret = walk_up_tree(trans, root, path, wc, parent_level);
6975 btrfs_free_path(path);
6979 static u64 update_block_group_flags(struct btrfs_root *root, u64 flags)
6982 u64 stripped = BTRFS_BLOCK_GROUP_RAID0 |
6983 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
6985 if (root->fs_info->balance_ctl) {
6986 struct btrfs_balance_control *bctl = root->fs_info->balance_ctl;
6989 /* pick restriper's target profile and return */
6990 if (flags & BTRFS_BLOCK_GROUP_DATA &&
6991 bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) {
6992 tgt = BTRFS_BLOCK_GROUP_DATA | bctl->data.target;
6993 } else if (flags & BTRFS_BLOCK_GROUP_SYSTEM &&
6994 bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
6995 tgt = BTRFS_BLOCK_GROUP_SYSTEM | bctl->sys.target;
6996 } else if (flags & BTRFS_BLOCK_GROUP_METADATA &&
6997 bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) {
6998 tgt = BTRFS_BLOCK_GROUP_METADATA | bctl->meta.target;
7002 /* extended -> chunk profile */
7003 tgt &= ~BTRFS_AVAIL_ALLOC_BIT_SINGLE;
7009 * we add in the count of missing devices because we want
7010 * to make sure that any RAID levels on a degraded FS
7011 * continue to be honored.
7013 num_devices = root->fs_info->fs_devices->rw_devices +
7014 root->fs_info->fs_devices->missing_devices;
7016 if (num_devices == 1) {
7017 stripped |= BTRFS_BLOCK_GROUP_DUP;
7018 stripped = flags & ~stripped;
7020 /* turn raid0 into single device chunks */
7021 if (flags & BTRFS_BLOCK_GROUP_RAID0)
7024 /* turn mirroring into duplication */
7025 if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
7026 BTRFS_BLOCK_GROUP_RAID10))
7027 return stripped | BTRFS_BLOCK_GROUP_DUP;
7030 /* they already had raid on here, just return */
7031 if (flags & stripped)
7034 stripped |= BTRFS_BLOCK_GROUP_DUP;
7035 stripped = flags & ~stripped;
7037 /* switch duplicated blocks with raid1 */
7038 if (flags & BTRFS_BLOCK_GROUP_DUP)
7039 return stripped | BTRFS_BLOCK_GROUP_RAID1;
7041 /* turn single device chunks into raid0 */
7042 return stripped | BTRFS_BLOCK_GROUP_RAID0;
7047 static int set_block_group_ro(struct btrfs_block_group_cache *cache, int force)
7049 struct btrfs_space_info *sinfo = cache->space_info;
7051 u64 min_allocable_bytes;
7056 * We need some metadata space and system metadata space for
7057 * allocating chunks in some corner cases until we force to set
7058 * it to be readonly.
7061 (BTRFS_BLOCK_GROUP_SYSTEM | BTRFS_BLOCK_GROUP_METADATA)) &&
7063 min_allocable_bytes = 1 * 1024 * 1024;
7065 min_allocable_bytes = 0;
7067 spin_lock(&sinfo->lock);
7068 spin_lock(&cache->lock);
7075 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
7076 cache->bytes_super - btrfs_block_group_used(&cache->item);
7078 if (sinfo->bytes_used + sinfo->bytes_reserved + sinfo->bytes_pinned +
7079 sinfo->bytes_may_use + sinfo->bytes_readonly + num_bytes +
7080 min_allocable_bytes <= sinfo->total_bytes) {
7081 sinfo->bytes_readonly += num_bytes;
7086 spin_unlock(&cache->lock);
7087 spin_unlock(&sinfo->lock);
7091 int btrfs_set_block_group_ro(struct btrfs_root *root,
7092 struct btrfs_block_group_cache *cache)
7095 struct btrfs_trans_handle *trans;
7101 trans = btrfs_join_transaction(root);
7102 BUG_ON(IS_ERR(trans));
7104 alloc_flags = update_block_group_flags(root, cache->flags);
7105 if (alloc_flags != cache->flags)
7106 do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags,
7109 ret = set_block_group_ro(cache, 0);
7112 alloc_flags = get_alloc_profile(root, cache->space_info->flags);
7113 ret = do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags,
7117 ret = set_block_group_ro(cache, 0);
7119 btrfs_end_transaction(trans, root);
7123 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans,
7124 struct btrfs_root *root, u64 type)
7126 u64 alloc_flags = get_alloc_profile(root, type);
7127 return do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags,
7132 * helper to account the unused space of all the readonly block group in the
7133 * list. takes mirrors into account.
7135 static u64 __btrfs_get_ro_block_group_free_space(struct list_head *groups_list)
7137 struct btrfs_block_group_cache *block_group;
7141 list_for_each_entry(block_group, groups_list, list) {
7142 spin_lock(&block_group->lock);
7144 if (!block_group->ro) {
7145 spin_unlock(&block_group->lock);
7149 if (block_group->flags & (BTRFS_BLOCK_GROUP_RAID1 |
7150 BTRFS_BLOCK_GROUP_RAID10 |
7151 BTRFS_BLOCK_GROUP_DUP))
7156 free_bytes += (block_group->key.offset -
7157 btrfs_block_group_used(&block_group->item)) *
7160 spin_unlock(&block_group->lock);
7167 * helper to account the unused space of all the readonly block group in the
7168 * space_info. takes mirrors into account.
7170 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo)
7175 spin_lock(&sinfo->lock);
7177 for(i = 0; i < BTRFS_NR_RAID_TYPES; i++)
7178 if (!list_empty(&sinfo->block_groups[i]))
7179 free_bytes += __btrfs_get_ro_block_group_free_space(
7180 &sinfo->block_groups[i]);
7182 spin_unlock(&sinfo->lock);
7187 void btrfs_set_block_group_rw(struct btrfs_root *root,
7188 struct btrfs_block_group_cache *cache)
7190 struct btrfs_space_info *sinfo = cache->space_info;
7195 spin_lock(&sinfo->lock);
7196 spin_lock(&cache->lock);
7197 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
7198 cache->bytes_super - btrfs_block_group_used(&cache->item);
7199 sinfo->bytes_readonly -= num_bytes;
7201 spin_unlock(&cache->lock);
7202 spin_unlock(&sinfo->lock);
7206 * checks to see if its even possible to relocate this block group.
7208 * @return - -1 if it's not a good idea to relocate this block group, 0 if its
7209 * ok to go ahead and try.
7211 int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
7213 struct btrfs_block_group_cache *block_group;
7214 struct btrfs_space_info *space_info;
7215 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
7216 struct btrfs_device *device;
7224 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
7226 /* odd, couldn't find the block group, leave it alone */
7230 min_free = btrfs_block_group_used(&block_group->item);
7232 /* no bytes used, we're good */
7236 space_info = block_group->space_info;
7237 spin_lock(&space_info->lock);
7239 full = space_info->full;
7242 * if this is the last block group we have in this space, we can't
7243 * relocate it unless we're able to allocate a new chunk below.
7245 * Otherwise, we need to make sure we have room in the space to handle
7246 * all of the extents from this block group. If we can, we're good
7248 if ((space_info->total_bytes != block_group->key.offset) &&
7249 (space_info->bytes_used + space_info->bytes_reserved +
7250 space_info->bytes_pinned + space_info->bytes_readonly +
7251 min_free < space_info->total_bytes)) {
7252 spin_unlock(&space_info->lock);
7255 spin_unlock(&space_info->lock);
7258 * ok we don't have enough space, but maybe we have free space on our
7259 * devices to allocate new chunks for relocation, so loop through our
7260 * alloc devices and guess if we have enough space. However, if we
7261 * were marked as full, then we know there aren't enough chunks, and we
7276 index = get_block_group_index(block_group);
7281 } else if (index == 1) {
7283 } else if (index == 2) {
7286 } else if (index == 3) {
7287 dev_min = fs_devices->rw_devices;
7288 do_div(min_free, dev_min);
7291 mutex_lock(&root->fs_info->chunk_mutex);
7292 list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
7296 * check to make sure we can actually find a chunk with enough
7297 * space to fit our block group in.
7299 if (device->total_bytes > device->bytes_used + min_free) {
7300 ret = find_free_dev_extent(device, min_free,
7305 if (dev_nr >= dev_min)
7311 mutex_unlock(&root->fs_info->chunk_mutex);
7313 btrfs_put_block_group(block_group);
7317 static int find_first_block_group(struct btrfs_root *root,
7318 struct btrfs_path *path, struct btrfs_key *key)
7321 struct btrfs_key found_key;
7322 struct extent_buffer *leaf;
7325 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
7330 slot = path->slots[0];
7331 leaf = path->nodes[0];
7332 if (slot >= btrfs_header_nritems(leaf)) {
7333 ret = btrfs_next_leaf(root, path);
7340 btrfs_item_key_to_cpu(leaf, &found_key, slot);
7342 if (found_key.objectid >= key->objectid &&
7343 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
7353 void btrfs_put_block_group_cache(struct btrfs_fs_info *info)
7355 struct btrfs_block_group_cache *block_group;
7359 struct inode *inode;
7361 block_group = btrfs_lookup_first_block_group(info, last);
7362 while (block_group) {
7363 spin_lock(&block_group->lock);
7364 if (block_group->iref)
7366 spin_unlock(&block_group->lock);
7367 block_group = next_block_group(info->tree_root,
7377 inode = block_group->inode;
7378 block_group->iref = 0;
7379 block_group->inode = NULL;
7380 spin_unlock(&block_group->lock);
7382 last = block_group->key.objectid + block_group->key.offset;
7383 btrfs_put_block_group(block_group);
7387 int btrfs_free_block_groups(struct btrfs_fs_info *info)
7389 struct btrfs_block_group_cache *block_group;
7390 struct btrfs_space_info *space_info;
7391 struct btrfs_caching_control *caching_ctl;
7394 down_write(&info->extent_commit_sem);
7395 while (!list_empty(&info->caching_block_groups)) {
7396 caching_ctl = list_entry(info->caching_block_groups.next,
7397 struct btrfs_caching_control, list);
7398 list_del(&caching_ctl->list);
7399 put_caching_control(caching_ctl);
7401 up_write(&info->extent_commit_sem);
7403 spin_lock(&info->block_group_cache_lock);
7404 while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
7405 block_group = rb_entry(n, struct btrfs_block_group_cache,
7407 rb_erase(&block_group->cache_node,
7408 &info->block_group_cache_tree);
7409 spin_unlock(&info->block_group_cache_lock);
7411 down_write(&block_group->space_info->groups_sem);
7412 list_del(&block_group->list);
7413 up_write(&block_group->space_info->groups_sem);
7415 if (block_group->cached == BTRFS_CACHE_STARTED)
7416 wait_block_group_cache_done(block_group);
7419 * We haven't cached this block group, which means we could
7420 * possibly have excluded extents on this block group.
7422 if (block_group->cached == BTRFS_CACHE_NO)
7423 free_excluded_extents(info->extent_root, block_group);
7425 btrfs_remove_free_space_cache(block_group);
7426 btrfs_put_block_group(block_group);
7428 spin_lock(&info->block_group_cache_lock);
7430 spin_unlock(&info->block_group_cache_lock);
7432 /* now that all the block groups are freed, go through and
7433 * free all the space_info structs. This is only called during
7434 * the final stages of unmount, and so we know nobody is
7435 * using them. We call synchronize_rcu() once before we start,
7436 * just to be on the safe side.
7440 release_global_block_rsv(info);
7442 while(!list_empty(&info->space_info)) {
7443 space_info = list_entry(info->space_info.next,
7444 struct btrfs_space_info,
7446 if (space_info->bytes_pinned > 0 ||
7447 space_info->bytes_reserved > 0 ||
7448 space_info->bytes_may_use > 0) {
7450 dump_space_info(space_info, 0, 0);
7452 list_del(&space_info->list);
7458 static void __link_block_group(struct btrfs_space_info *space_info,
7459 struct btrfs_block_group_cache *cache)
7461 int index = get_block_group_index(cache);
7463 down_write(&space_info->groups_sem);
7464 list_add_tail(&cache->list, &space_info->block_groups[index]);
7465 up_write(&space_info->groups_sem);
7468 int btrfs_read_block_groups(struct btrfs_root *root)
7470 struct btrfs_path *path;
7472 struct btrfs_block_group_cache *cache;
7473 struct btrfs_fs_info *info = root->fs_info;
7474 struct btrfs_space_info *space_info;
7475 struct btrfs_key key;
7476 struct btrfs_key found_key;
7477 struct extent_buffer *leaf;
7481 root = info->extent_root;
7484 btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
7485 path = btrfs_alloc_path();
7490 cache_gen = btrfs_super_cache_generation(root->fs_info->super_copy);
7491 if (btrfs_test_opt(root, SPACE_CACHE) &&
7492 btrfs_super_generation(root->fs_info->super_copy) != cache_gen)
7494 if (btrfs_test_opt(root, CLEAR_CACHE))
7498 ret = find_first_block_group(root, path, &key);
7503 leaf = path->nodes[0];
7504 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
7505 cache = kzalloc(sizeof(*cache), GFP_NOFS);
7510 cache->free_space_ctl = kzalloc(sizeof(*cache->free_space_ctl),
7512 if (!cache->free_space_ctl) {
7518 atomic_set(&cache->count, 1);
7519 spin_lock_init(&cache->lock);
7520 cache->fs_info = info;
7521 INIT_LIST_HEAD(&cache->list);
7522 INIT_LIST_HEAD(&cache->cluster_list);
7525 cache->disk_cache_state = BTRFS_DC_CLEAR;
7527 read_extent_buffer(leaf, &cache->item,
7528 btrfs_item_ptr_offset(leaf, path->slots[0]),
7529 sizeof(cache->item));
7530 memcpy(&cache->key, &found_key, sizeof(found_key));
7532 key.objectid = found_key.objectid + found_key.offset;
7533 btrfs_release_path(path);
7534 cache->flags = btrfs_block_group_flags(&cache->item);
7535 cache->sectorsize = root->sectorsize;
7537 btrfs_init_free_space_ctl(cache);
7540 * We need to exclude the super stripes now so that the space
7541 * info has super bytes accounted for, otherwise we'll think
7542 * we have more space than we actually do.
7544 exclude_super_stripes(root, cache);
7547 * check for two cases, either we are full, and therefore
7548 * don't need to bother with the caching work since we won't
7549 * find any space, or we are empty, and we can just add all
7550 * the space in and be done with it. This saves us _alot_ of
7551 * time, particularly in the full case.
7553 if (found_key.offset == btrfs_block_group_used(&cache->item)) {
7554 cache->last_byte_to_unpin = (u64)-1;
7555 cache->cached = BTRFS_CACHE_FINISHED;
7556 free_excluded_extents(root, cache);
7557 } else if (btrfs_block_group_used(&cache->item) == 0) {
7558 cache->last_byte_to_unpin = (u64)-1;
7559 cache->cached = BTRFS_CACHE_FINISHED;
7560 add_new_free_space(cache, root->fs_info,
7562 found_key.objectid +
7564 free_excluded_extents(root, cache);
7567 ret = update_space_info(info, cache->flags, found_key.offset,
7568 btrfs_block_group_used(&cache->item),
7571 cache->space_info = space_info;
7572 spin_lock(&cache->space_info->lock);
7573 cache->space_info->bytes_readonly += cache->bytes_super;
7574 spin_unlock(&cache->space_info->lock);
7576 __link_block_group(space_info, cache);
7578 ret = btrfs_add_block_group_cache(root->fs_info, cache);
7581 set_avail_alloc_bits(root->fs_info, cache->flags);
7582 if (btrfs_chunk_readonly(root, cache->key.objectid))
7583 set_block_group_ro(cache, 1);
7586 list_for_each_entry_rcu(space_info, &root->fs_info->space_info, list) {
7587 if (!(get_alloc_profile(root, space_info->flags) &
7588 (BTRFS_BLOCK_GROUP_RAID10 |
7589 BTRFS_BLOCK_GROUP_RAID1 |
7590 BTRFS_BLOCK_GROUP_DUP)))
7593 * avoid allocating from un-mirrored block group if there are
7594 * mirrored block groups.
7596 list_for_each_entry(cache, &space_info->block_groups[3], list)
7597 set_block_group_ro(cache, 1);
7598 list_for_each_entry(cache, &space_info->block_groups[4], list)
7599 set_block_group_ro(cache, 1);
7602 init_global_block_rsv(info);
7605 btrfs_free_path(path);
7609 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
7610 struct btrfs_root *root, u64 bytes_used,
7611 u64 type, u64 chunk_objectid, u64 chunk_offset,
7615 struct btrfs_root *extent_root;
7616 struct btrfs_block_group_cache *cache;
7618 extent_root = root->fs_info->extent_root;
7620 root->fs_info->last_trans_log_full_commit = trans->transid;
7622 cache = kzalloc(sizeof(*cache), GFP_NOFS);
7625 cache->free_space_ctl = kzalloc(sizeof(*cache->free_space_ctl),
7627 if (!cache->free_space_ctl) {
7632 cache->key.objectid = chunk_offset;
7633 cache->key.offset = size;
7634 cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
7635 cache->sectorsize = root->sectorsize;
7636 cache->fs_info = root->fs_info;
7638 atomic_set(&cache->count, 1);
7639 spin_lock_init(&cache->lock);
7640 INIT_LIST_HEAD(&cache->list);
7641 INIT_LIST_HEAD(&cache->cluster_list);
7643 btrfs_init_free_space_ctl(cache);
7645 btrfs_set_block_group_used(&cache->item, bytes_used);
7646 btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
7647 cache->flags = type;
7648 btrfs_set_block_group_flags(&cache->item, type);
7650 cache->last_byte_to_unpin = (u64)-1;
7651 cache->cached = BTRFS_CACHE_FINISHED;
7652 exclude_super_stripes(root, cache);
7654 add_new_free_space(cache, root->fs_info, chunk_offset,
7655 chunk_offset + size);
7657 free_excluded_extents(root, cache);
7659 ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
7660 &cache->space_info);
7662 update_global_block_rsv(root->fs_info);
7664 spin_lock(&cache->space_info->lock);
7665 cache->space_info->bytes_readonly += cache->bytes_super;
7666 spin_unlock(&cache->space_info->lock);
7668 __link_block_group(cache->space_info, cache);
7670 ret = btrfs_add_block_group_cache(root->fs_info, cache);
7673 ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
7674 sizeof(cache->item));
7677 set_avail_alloc_bits(extent_root->fs_info, type);
7682 static void clear_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
7684 u64 extra_flags = flags & BTRFS_BLOCK_GROUP_PROFILE_MASK;
7686 /* chunk -> extended profile */
7687 if (extra_flags == 0)
7688 extra_flags = BTRFS_AVAIL_ALLOC_BIT_SINGLE;
7690 if (flags & BTRFS_BLOCK_GROUP_DATA)
7691 fs_info->avail_data_alloc_bits &= ~extra_flags;
7692 if (flags & BTRFS_BLOCK_GROUP_METADATA)
7693 fs_info->avail_metadata_alloc_bits &= ~extra_flags;
7694 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
7695 fs_info->avail_system_alloc_bits &= ~extra_flags;
7698 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
7699 struct btrfs_root *root, u64 group_start)
7701 struct btrfs_path *path;
7702 struct btrfs_block_group_cache *block_group;
7703 struct btrfs_free_cluster *cluster;
7704 struct btrfs_root *tree_root = root->fs_info->tree_root;
7705 struct btrfs_key key;
7706 struct inode *inode;
7711 root = root->fs_info->extent_root;
7713 block_group = btrfs_lookup_block_group(root->fs_info, group_start);
7714 BUG_ON(!block_group);
7715 BUG_ON(!block_group->ro);
7718 * Free the reserved super bytes from this block group before
7721 free_excluded_extents(root, block_group);
7723 memcpy(&key, &block_group->key, sizeof(key));
7724 index = get_block_group_index(block_group);
7725 if (block_group->flags & (BTRFS_BLOCK_GROUP_DUP |
7726 BTRFS_BLOCK_GROUP_RAID1 |
7727 BTRFS_BLOCK_GROUP_RAID10))
7732 /* make sure this block group isn't part of an allocation cluster */
7733 cluster = &root->fs_info->data_alloc_cluster;
7734 spin_lock(&cluster->refill_lock);
7735 btrfs_return_cluster_to_free_space(block_group, cluster);
7736 spin_unlock(&cluster->refill_lock);
7739 * make sure this block group isn't part of a metadata
7740 * allocation cluster
7742 cluster = &root->fs_info->meta_alloc_cluster;
7743 spin_lock(&cluster->refill_lock);
7744 btrfs_return_cluster_to_free_space(block_group, cluster);
7745 spin_unlock(&cluster->refill_lock);
7747 path = btrfs_alloc_path();
7753 inode = lookup_free_space_inode(tree_root, block_group, path);
7754 if (!IS_ERR(inode)) {
7755 ret = btrfs_orphan_add(trans, inode);
7758 /* One for the block groups ref */
7759 spin_lock(&block_group->lock);
7760 if (block_group->iref) {
7761 block_group->iref = 0;
7762 block_group->inode = NULL;
7763 spin_unlock(&block_group->lock);
7766 spin_unlock(&block_group->lock);
7768 /* One for our lookup ref */
7769 btrfs_add_delayed_iput(inode);
7772 key.objectid = BTRFS_FREE_SPACE_OBJECTID;
7773 key.offset = block_group->key.objectid;
7776 ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1);
7780 btrfs_release_path(path);
7782 ret = btrfs_del_item(trans, tree_root, path);
7785 btrfs_release_path(path);
7788 spin_lock(&root->fs_info->block_group_cache_lock);
7789 rb_erase(&block_group->cache_node,
7790 &root->fs_info->block_group_cache_tree);
7791 spin_unlock(&root->fs_info->block_group_cache_lock);
7793 down_write(&block_group->space_info->groups_sem);
7795 * we must use list_del_init so people can check to see if they
7796 * are still on the list after taking the semaphore
7798 list_del_init(&block_group->list);
7799 if (list_empty(&block_group->space_info->block_groups[index]))
7800 clear_avail_alloc_bits(root->fs_info, block_group->flags);
7801 up_write(&block_group->space_info->groups_sem);
7803 if (block_group->cached == BTRFS_CACHE_STARTED)
7804 wait_block_group_cache_done(block_group);
7806 btrfs_remove_free_space_cache(block_group);
7808 spin_lock(&block_group->space_info->lock);
7809 block_group->space_info->total_bytes -= block_group->key.offset;
7810 block_group->space_info->bytes_readonly -= block_group->key.offset;
7811 block_group->space_info->disk_total -= block_group->key.offset * factor;
7812 spin_unlock(&block_group->space_info->lock);
7814 memcpy(&key, &block_group->key, sizeof(key));
7816 btrfs_clear_space_info_full(root->fs_info);
7818 btrfs_put_block_group(block_group);
7819 btrfs_put_block_group(block_group);
7821 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
7827 ret = btrfs_del_item(trans, root, path);
7829 btrfs_free_path(path);
7833 int btrfs_init_space_info(struct btrfs_fs_info *fs_info)
7835 struct btrfs_space_info *space_info;
7836 struct btrfs_super_block *disk_super;
7842 disk_super = fs_info->super_copy;
7843 if (!btrfs_super_root(disk_super))
7846 features = btrfs_super_incompat_flags(disk_super);
7847 if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
7850 flags = BTRFS_BLOCK_GROUP_SYSTEM;
7851 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
7856 flags = BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA;
7857 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
7859 flags = BTRFS_BLOCK_GROUP_METADATA;
7860 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
7864 flags = BTRFS_BLOCK_GROUP_DATA;
7865 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
7871 int btrfs_error_unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
7873 return unpin_extent_range(root, start, end);
7876 int btrfs_error_discard_extent(struct btrfs_root *root, u64 bytenr,
7877 u64 num_bytes, u64 *actual_bytes)
7879 return btrfs_discard_extent(root, bytenr, num_bytes, actual_bytes);
7882 int btrfs_trim_fs(struct btrfs_root *root, struct fstrim_range *range)
7884 struct btrfs_fs_info *fs_info = root->fs_info;
7885 struct btrfs_block_group_cache *cache = NULL;
7890 u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
7894 * try to trim all FS space, our block group may start from non-zero.
7896 if (range->len == total_bytes)
7897 cache = btrfs_lookup_first_block_group(fs_info, range->start);
7899 cache = btrfs_lookup_block_group(fs_info, range->start);
7902 if (cache->key.objectid >= (range->start + range->len)) {
7903 btrfs_put_block_group(cache);
7907 start = max(range->start, cache->key.objectid);
7908 end = min(range->start + range->len,
7909 cache->key.objectid + cache->key.offset);
7911 if (end - start >= range->minlen) {
7912 if (!block_group_cache_done(cache)) {
7913 ret = cache_block_group(cache, NULL, root, 0);
7915 wait_block_group_cache_done(cache);
7917 ret = btrfs_trim_block_group(cache,
7923 trimmed += group_trimmed;
7925 btrfs_put_block_group(cache);
7930 cache = next_block_group(fs_info->tree_root, cache);
7933 range->len = trimmed;