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>
30 #include "print-tree.h"
31 #include "transaction.h"
34 #include "free-space-cache.h"
36 /* control flags for do_chunk_alloc's force field
37 * CHUNK_ALLOC_NO_FORCE means to only allocate a chunk
38 * if we really need one.
40 * CHUNK_ALLOC_FORCE means it must try to allocate 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
50 CHUNK_ALLOC_NO_FORCE = 0,
51 CHUNK_ALLOC_FORCE = 1,
52 CHUNK_ALLOC_LIMITED = 2,
56 * Control how reservations are dealt with.
58 * RESERVE_FREE - freeing a reservation.
59 * RESERVE_ALLOC - allocating space and we need to update bytes_may_use for
61 * RESERVE_ALLOC_NO_ACCOUNT - allocating space and we should not update
62 * bytes_may_use as the ENOSPC accounting is done elsewhere
67 RESERVE_ALLOC_NO_ACCOUNT = 2,
70 static int update_block_group(struct btrfs_trans_handle *trans,
71 struct btrfs_root *root,
72 u64 bytenr, u64 num_bytes, int alloc);
73 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
74 struct btrfs_root *root,
75 u64 bytenr, u64 num_bytes, u64 parent,
76 u64 root_objectid, u64 owner_objectid,
77 u64 owner_offset, int refs_to_drop,
78 struct btrfs_delayed_extent_op *extra_op);
79 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
80 struct extent_buffer *leaf,
81 struct btrfs_extent_item *ei);
82 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
83 struct btrfs_root *root,
84 u64 parent, u64 root_objectid,
85 u64 flags, u64 owner, u64 offset,
86 struct btrfs_key *ins, int ref_mod);
87 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
88 struct btrfs_root *root,
89 u64 parent, u64 root_objectid,
90 u64 flags, struct btrfs_disk_key *key,
91 int level, struct btrfs_key *ins);
92 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
93 struct btrfs_root *extent_root, u64 alloc_bytes,
94 u64 flags, int force);
95 static int find_next_key(struct btrfs_path *path, int level,
96 struct btrfs_key *key);
97 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
98 int dump_block_groups);
99 static int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache,
100 u64 num_bytes, int reserve);
103 block_group_cache_done(struct btrfs_block_group_cache *cache)
106 return cache->cached == BTRFS_CACHE_FINISHED;
109 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
111 return (cache->flags & bits) == bits;
114 static void btrfs_get_block_group(struct btrfs_block_group_cache *cache)
116 atomic_inc(&cache->count);
119 void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
121 if (atomic_dec_and_test(&cache->count)) {
122 WARN_ON(cache->pinned > 0);
123 WARN_ON(cache->reserved > 0);
124 kfree(cache->free_space_ctl);
130 * this adds the block group to the fs_info rb tree for the block group
133 static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
134 struct btrfs_block_group_cache *block_group)
137 struct rb_node *parent = NULL;
138 struct btrfs_block_group_cache *cache;
140 spin_lock(&info->block_group_cache_lock);
141 p = &info->block_group_cache_tree.rb_node;
145 cache = rb_entry(parent, struct btrfs_block_group_cache,
147 if (block_group->key.objectid < cache->key.objectid) {
149 } else if (block_group->key.objectid > cache->key.objectid) {
152 spin_unlock(&info->block_group_cache_lock);
157 rb_link_node(&block_group->cache_node, parent, p);
158 rb_insert_color(&block_group->cache_node,
159 &info->block_group_cache_tree);
160 spin_unlock(&info->block_group_cache_lock);
166 * This will return the block group at or after bytenr if contains is 0, else
167 * it will return the block group that contains the bytenr
169 static struct btrfs_block_group_cache *
170 block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
173 struct btrfs_block_group_cache *cache, *ret = NULL;
177 spin_lock(&info->block_group_cache_lock);
178 n = info->block_group_cache_tree.rb_node;
181 cache = rb_entry(n, struct btrfs_block_group_cache,
183 end = cache->key.objectid + cache->key.offset - 1;
184 start = cache->key.objectid;
186 if (bytenr < start) {
187 if (!contains && (!ret || start < ret->key.objectid))
190 } else if (bytenr > start) {
191 if (contains && bytenr <= end) {
202 btrfs_get_block_group(ret);
203 spin_unlock(&info->block_group_cache_lock);
208 static int add_excluded_extent(struct btrfs_root *root,
209 u64 start, u64 num_bytes)
211 u64 end = start + num_bytes - 1;
212 set_extent_bits(&root->fs_info->freed_extents[0],
213 start, end, EXTENT_UPTODATE, GFP_NOFS);
214 set_extent_bits(&root->fs_info->freed_extents[1],
215 start, end, EXTENT_UPTODATE, GFP_NOFS);
219 static void free_excluded_extents(struct btrfs_root *root,
220 struct btrfs_block_group_cache *cache)
224 start = cache->key.objectid;
225 end = start + cache->key.offset - 1;
227 clear_extent_bits(&root->fs_info->freed_extents[0],
228 start, end, EXTENT_UPTODATE, GFP_NOFS);
229 clear_extent_bits(&root->fs_info->freed_extents[1],
230 start, end, EXTENT_UPTODATE, GFP_NOFS);
233 static int exclude_super_stripes(struct btrfs_root *root,
234 struct btrfs_block_group_cache *cache)
241 if (cache->key.objectid < BTRFS_SUPER_INFO_OFFSET) {
242 stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->key.objectid;
243 cache->bytes_super += stripe_len;
244 ret = add_excluded_extent(root, cache->key.objectid,
249 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
250 bytenr = btrfs_sb_offset(i);
251 ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
252 cache->key.objectid, bytenr,
253 0, &logical, &nr, &stripe_len);
257 cache->bytes_super += stripe_len;
258 ret = add_excluded_extent(root, logical[nr],
268 static struct btrfs_caching_control *
269 get_caching_control(struct btrfs_block_group_cache *cache)
271 struct btrfs_caching_control *ctl;
273 spin_lock(&cache->lock);
274 if (cache->cached != BTRFS_CACHE_STARTED) {
275 spin_unlock(&cache->lock);
279 /* We're loading it the fast way, so we don't have a caching_ctl. */
280 if (!cache->caching_ctl) {
281 spin_unlock(&cache->lock);
285 ctl = cache->caching_ctl;
286 atomic_inc(&ctl->count);
287 spin_unlock(&cache->lock);
291 static void put_caching_control(struct btrfs_caching_control *ctl)
293 if (atomic_dec_and_test(&ctl->count))
298 * this is only called by cache_block_group, since we could have freed extents
299 * we need to check the pinned_extents for any extents that can't be used yet
300 * since their free space will be released as soon as the transaction commits.
302 static u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
303 struct btrfs_fs_info *info, u64 start, u64 end)
305 u64 extent_start, extent_end, size, total_added = 0;
308 while (start < end) {
309 ret = find_first_extent_bit(info->pinned_extents, start,
310 &extent_start, &extent_end,
311 EXTENT_DIRTY | EXTENT_UPTODATE);
315 if (extent_start <= start) {
316 start = extent_end + 1;
317 } else if (extent_start > start && extent_start < end) {
318 size = extent_start - start;
320 ret = btrfs_add_free_space(block_group, start,
323 start = extent_end + 1;
332 ret = btrfs_add_free_space(block_group, start, size);
339 static noinline void caching_thread(struct btrfs_work *work)
341 struct btrfs_block_group_cache *block_group;
342 struct btrfs_fs_info *fs_info;
343 struct btrfs_caching_control *caching_ctl;
344 struct btrfs_root *extent_root;
345 struct btrfs_path *path;
346 struct extent_buffer *leaf;
347 struct btrfs_key key;
353 caching_ctl = container_of(work, struct btrfs_caching_control, work);
354 block_group = caching_ctl->block_group;
355 fs_info = block_group->fs_info;
356 extent_root = fs_info->extent_root;
358 path = btrfs_alloc_path();
362 last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
365 * We don't want to deadlock with somebody trying to allocate a new
366 * extent for the extent root while also trying to search the extent
367 * root to add free space. So we skip locking and search the commit
368 * root, since its read-only
370 path->skip_locking = 1;
371 path->search_commit_root = 1;
376 key.type = BTRFS_EXTENT_ITEM_KEY;
378 mutex_lock(&caching_ctl->mutex);
379 /* need to make sure the commit_root doesn't disappear */
380 down_read(&fs_info->extent_commit_sem);
382 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
386 leaf = path->nodes[0];
387 nritems = btrfs_header_nritems(leaf);
390 if (btrfs_fs_closing(fs_info) > 1) {
395 if (path->slots[0] < nritems) {
396 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
398 ret = find_next_key(path, 0, &key);
402 if (need_resched() ||
403 btrfs_next_leaf(extent_root, path)) {
404 caching_ctl->progress = last;
405 btrfs_release_path(path);
406 up_read(&fs_info->extent_commit_sem);
407 mutex_unlock(&caching_ctl->mutex);
411 leaf = path->nodes[0];
412 nritems = btrfs_header_nritems(leaf);
416 if (key.objectid < block_group->key.objectid) {
421 if (key.objectid >= block_group->key.objectid +
422 block_group->key.offset)
425 if (key.type == BTRFS_EXTENT_ITEM_KEY) {
426 total_found += add_new_free_space(block_group,
429 last = key.objectid + key.offset;
431 if (total_found > (1024 * 1024 * 2)) {
433 wake_up(&caching_ctl->wait);
440 total_found += add_new_free_space(block_group, fs_info, last,
441 block_group->key.objectid +
442 block_group->key.offset);
443 caching_ctl->progress = (u64)-1;
445 spin_lock(&block_group->lock);
446 block_group->caching_ctl = NULL;
447 block_group->cached = BTRFS_CACHE_FINISHED;
448 spin_unlock(&block_group->lock);
451 btrfs_free_path(path);
452 up_read(&fs_info->extent_commit_sem);
454 free_excluded_extents(extent_root, block_group);
456 mutex_unlock(&caching_ctl->mutex);
458 wake_up(&caching_ctl->wait);
460 put_caching_control(caching_ctl);
461 btrfs_put_block_group(block_group);
464 static int cache_block_group(struct btrfs_block_group_cache *cache,
465 struct btrfs_trans_handle *trans,
466 struct btrfs_root *root,
469 struct btrfs_fs_info *fs_info = cache->fs_info;
470 struct btrfs_caching_control *caching_ctl;
474 if (cache->cached != BTRFS_CACHE_NO)
478 * We can't do the read from on-disk cache during a commit since we need
479 * to have the normal tree locking. Also if we are currently trying to
480 * allocate blocks for the tree root we can't do the fast caching since
481 * we likely hold important locks.
483 if (trans && (!trans->transaction->in_commit) &&
484 (root && root != root->fs_info->tree_root)) {
485 spin_lock(&cache->lock);
486 if (cache->cached != BTRFS_CACHE_NO) {
487 spin_unlock(&cache->lock);
490 cache->cached = BTRFS_CACHE_STARTED;
491 spin_unlock(&cache->lock);
493 ret = load_free_space_cache(fs_info, cache);
495 spin_lock(&cache->lock);
497 cache->cached = BTRFS_CACHE_FINISHED;
498 cache->last_byte_to_unpin = (u64)-1;
500 cache->cached = BTRFS_CACHE_NO;
502 spin_unlock(&cache->lock);
504 free_excluded_extents(fs_info->extent_root, cache);
512 caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_NOFS);
513 BUG_ON(!caching_ctl);
515 INIT_LIST_HEAD(&caching_ctl->list);
516 mutex_init(&caching_ctl->mutex);
517 init_waitqueue_head(&caching_ctl->wait);
518 caching_ctl->block_group = cache;
519 caching_ctl->progress = cache->key.objectid;
520 /* one for caching kthread, one for caching block group list */
521 atomic_set(&caching_ctl->count, 2);
522 caching_ctl->work.func = caching_thread;
524 spin_lock(&cache->lock);
525 if (cache->cached != BTRFS_CACHE_NO) {
526 spin_unlock(&cache->lock);
530 cache->caching_ctl = caching_ctl;
531 cache->cached = BTRFS_CACHE_STARTED;
532 spin_unlock(&cache->lock);
534 down_write(&fs_info->extent_commit_sem);
535 list_add_tail(&caching_ctl->list, &fs_info->caching_block_groups);
536 up_write(&fs_info->extent_commit_sem);
538 btrfs_get_block_group(cache);
540 btrfs_queue_worker(&fs_info->caching_workers, &caching_ctl->work);
546 * return the block group that starts at or after bytenr
548 static struct btrfs_block_group_cache *
549 btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr)
551 struct btrfs_block_group_cache *cache;
553 cache = block_group_cache_tree_search(info, bytenr, 0);
559 * return the block group that contains the given bytenr
561 struct btrfs_block_group_cache *btrfs_lookup_block_group(
562 struct btrfs_fs_info *info,
565 struct btrfs_block_group_cache *cache;
567 cache = block_group_cache_tree_search(info, bytenr, 1);
572 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
575 struct list_head *head = &info->space_info;
576 struct btrfs_space_info *found;
578 flags &= BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_SYSTEM |
579 BTRFS_BLOCK_GROUP_METADATA;
582 list_for_each_entry_rcu(found, head, list) {
583 if (found->flags & flags) {
593 * after adding space to the filesystem, we need to clear the full flags
594 * on all the space infos.
596 void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
598 struct list_head *head = &info->space_info;
599 struct btrfs_space_info *found;
602 list_for_each_entry_rcu(found, head, list)
607 static u64 div_factor(u64 num, int factor)
616 static u64 div_factor_fine(u64 num, int factor)
625 u64 btrfs_find_block_group(struct btrfs_root *root,
626 u64 search_start, u64 search_hint, int owner)
628 struct btrfs_block_group_cache *cache;
630 u64 last = max(search_hint, search_start);
637 cache = btrfs_lookup_first_block_group(root->fs_info, last);
641 spin_lock(&cache->lock);
642 last = cache->key.objectid + cache->key.offset;
643 used = btrfs_block_group_used(&cache->item);
645 if ((full_search || !cache->ro) &&
646 block_group_bits(cache, BTRFS_BLOCK_GROUP_METADATA)) {
647 if (used + cache->pinned + cache->reserved <
648 div_factor(cache->key.offset, factor)) {
649 group_start = cache->key.objectid;
650 spin_unlock(&cache->lock);
651 btrfs_put_block_group(cache);
655 spin_unlock(&cache->lock);
656 btrfs_put_block_group(cache);
664 if (!full_search && factor < 10) {
674 /* simple helper to search for an existing extent at a given offset */
675 int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len)
678 struct btrfs_key key;
679 struct btrfs_path *path;
681 path = btrfs_alloc_path();
685 key.objectid = start;
687 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
688 ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path,
690 btrfs_free_path(path);
695 * helper function to lookup reference count and flags of extent.
697 * the head node for delayed ref is used to store the sum of all the
698 * reference count modifications queued up in the rbtree. the head
699 * node may also store the extent flags to set. This way you can check
700 * to see what the reference count and extent flags would be if all of
701 * the delayed refs are not processed.
703 int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
704 struct btrfs_root *root, u64 bytenr,
705 u64 num_bytes, u64 *refs, u64 *flags)
707 struct btrfs_delayed_ref_head *head;
708 struct btrfs_delayed_ref_root *delayed_refs;
709 struct btrfs_path *path;
710 struct btrfs_extent_item *ei;
711 struct extent_buffer *leaf;
712 struct btrfs_key key;
718 path = btrfs_alloc_path();
722 key.objectid = bytenr;
723 key.type = BTRFS_EXTENT_ITEM_KEY;
724 key.offset = num_bytes;
726 path->skip_locking = 1;
727 path->search_commit_root = 1;
730 ret = btrfs_search_slot(trans, root->fs_info->extent_root,
736 leaf = path->nodes[0];
737 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
738 if (item_size >= sizeof(*ei)) {
739 ei = btrfs_item_ptr(leaf, path->slots[0],
740 struct btrfs_extent_item);
741 num_refs = btrfs_extent_refs(leaf, ei);
742 extent_flags = btrfs_extent_flags(leaf, ei);
744 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
745 struct btrfs_extent_item_v0 *ei0;
746 BUG_ON(item_size != sizeof(*ei0));
747 ei0 = btrfs_item_ptr(leaf, path->slots[0],
748 struct btrfs_extent_item_v0);
749 num_refs = btrfs_extent_refs_v0(leaf, ei0);
750 /* FIXME: this isn't correct for data */
751 extent_flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
756 BUG_ON(num_refs == 0);
766 delayed_refs = &trans->transaction->delayed_refs;
767 spin_lock(&delayed_refs->lock);
768 head = btrfs_find_delayed_ref_head(trans, bytenr);
770 if (!mutex_trylock(&head->mutex)) {
771 atomic_inc(&head->node.refs);
772 spin_unlock(&delayed_refs->lock);
774 btrfs_release_path(path);
777 * Mutex was contended, block until it's released and try
780 mutex_lock(&head->mutex);
781 mutex_unlock(&head->mutex);
782 btrfs_put_delayed_ref(&head->node);
785 if (head->extent_op && head->extent_op->update_flags)
786 extent_flags |= head->extent_op->flags_to_set;
788 BUG_ON(num_refs == 0);
790 num_refs += head->node.ref_mod;
791 mutex_unlock(&head->mutex);
793 spin_unlock(&delayed_refs->lock);
795 WARN_ON(num_refs == 0);
799 *flags = extent_flags;
801 btrfs_free_path(path);
806 * Back reference rules. Back refs have three main goals:
808 * 1) differentiate between all holders of references to an extent so that
809 * when a reference is dropped we can make sure it was a valid reference
810 * before freeing the extent.
812 * 2) Provide enough information to quickly find the holders of an extent
813 * if we notice a given block is corrupted or bad.
815 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
816 * maintenance. This is actually the same as #2, but with a slightly
817 * different use case.
819 * There are two kinds of back refs. The implicit back refs is optimized
820 * for pointers in non-shared tree blocks. For a given pointer in a block,
821 * back refs of this kind provide information about the block's owner tree
822 * and the pointer's key. These information allow us to find the block by
823 * b-tree searching. The full back refs is for pointers in tree blocks not
824 * referenced by their owner trees. The location of tree block is recorded
825 * in the back refs. Actually the full back refs is generic, and can be
826 * used in all cases the implicit back refs is used. The major shortcoming
827 * of the full back refs is its overhead. Every time a tree block gets
828 * COWed, we have to update back refs entry for all pointers in it.
830 * For a newly allocated tree block, we use implicit back refs for
831 * pointers in it. This means most tree related operations only involve
832 * implicit back refs. For a tree block created in old transaction, the
833 * only way to drop a reference to it is COW it. So we can detect the
834 * event that tree block loses its owner tree's reference and do the
835 * back refs conversion.
837 * When a tree block is COW'd through a tree, there are four cases:
839 * The reference count of the block is one and the tree is the block's
840 * owner tree. Nothing to do in this case.
842 * The reference count of the block is one and the tree is not the
843 * block's owner tree. In this case, full back refs is used for pointers
844 * in the block. Remove these full back refs, add implicit back refs for
845 * every pointers in the new block.
847 * The reference count of the block is greater than one and the tree is
848 * the block's owner tree. In this case, implicit back refs is used for
849 * pointers in the block. Add full back refs for every pointers in the
850 * block, increase lower level extents' reference counts. The original
851 * implicit back refs are entailed to the new block.
853 * The reference count of the block is greater than one and the tree is
854 * not the block's owner tree. Add implicit back refs for every pointer in
855 * the new block, increase lower level extents' reference count.
857 * Back Reference Key composing:
859 * The key objectid corresponds to the first byte in the extent,
860 * The key type is used to differentiate between types of back refs.
861 * There are different meanings of the key offset for different types
864 * File extents can be referenced by:
866 * - multiple snapshots, subvolumes, or different generations in one subvol
867 * - different files inside a single subvolume
868 * - different offsets inside a file (bookend extents in file.c)
870 * The extent ref structure for the implicit back refs has fields for:
872 * - Objectid of the subvolume root
873 * - objectid of the file holding the reference
874 * - original offset in the file
875 * - how many bookend extents
877 * The key offset for the implicit back refs is hash of the first
880 * The extent ref structure for the full back refs has field for:
882 * - number of pointers in the tree leaf
884 * The key offset for the implicit back refs is the first byte of
887 * When a file extent is allocated, The implicit back refs is used.
888 * the fields are filled in:
890 * (root_key.objectid, inode objectid, offset in file, 1)
892 * When a file extent is removed file truncation, we find the
893 * corresponding implicit back refs and check the following fields:
895 * (btrfs_header_owner(leaf), inode objectid, offset in file)
897 * Btree extents can be referenced by:
899 * - Different subvolumes
901 * Both the implicit back refs and the full back refs for tree blocks
902 * only consist of key. The key offset for the implicit back refs is
903 * objectid of block's owner tree. The key offset for the full back refs
904 * is the first byte of parent block.
906 * When implicit back refs is used, information about the lowest key and
907 * level of the tree block are required. These information are stored in
908 * tree block info structure.
911 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
912 static int convert_extent_item_v0(struct btrfs_trans_handle *trans,
913 struct btrfs_root *root,
914 struct btrfs_path *path,
915 u64 owner, u32 extra_size)
917 struct btrfs_extent_item *item;
918 struct btrfs_extent_item_v0 *ei0;
919 struct btrfs_extent_ref_v0 *ref0;
920 struct btrfs_tree_block_info *bi;
921 struct extent_buffer *leaf;
922 struct btrfs_key key;
923 struct btrfs_key found_key;
924 u32 new_size = sizeof(*item);
928 leaf = path->nodes[0];
929 BUG_ON(btrfs_item_size_nr(leaf, path->slots[0]) != sizeof(*ei0));
931 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
932 ei0 = btrfs_item_ptr(leaf, path->slots[0],
933 struct btrfs_extent_item_v0);
934 refs = btrfs_extent_refs_v0(leaf, ei0);
936 if (owner == (u64)-1) {
938 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
939 ret = btrfs_next_leaf(root, path);
943 leaf = path->nodes[0];
945 btrfs_item_key_to_cpu(leaf, &found_key,
947 BUG_ON(key.objectid != found_key.objectid);
948 if (found_key.type != BTRFS_EXTENT_REF_V0_KEY) {
952 ref0 = btrfs_item_ptr(leaf, path->slots[0],
953 struct btrfs_extent_ref_v0);
954 owner = btrfs_ref_objectid_v0(leaf, ref0);
958 btrfs_release_path(path);
960 if (owner < BTRFS_FIRST_FREE_OBJECTID)
961 new_size += sizeof(*bi);
963 new_size -= sizeof(*ei0);
964 ret = btrfs_search_slot(trans, root, &key, path,
965 new_size + extra_size, 1);
970 ret = btrfs_extend_item(trans, root, path, new_size);
972 leaf = path->nodes[0];
973 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
974 btrfs_set_extent_refs(leaf, item, refs);
975 /* FIXME: get real generation */
976 btrfs_set_extent_generation(leaf, item, 0);
977 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
978 btrfs_set_extent_flags(leaf, item,
979 BTRFS_EXTENT_FLAG_TREE_BLOCK |
980 BTRFS_BLOCK_FLAG_FULL_BACKREF);
981 bi = (struct btrfs_tree_block_info *)(item + 1);
982 /* FIXME: get first key of the block */
983 memset_extent_buffer(leaf, 0, (unsigned long)bi, sizeof(*bi));
984 btrfs_set_tree_block_level(leaf, bi, (int)owner);
986 btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_DATA);
988 btrfs_mark_buffer_dirty(leaf);
993 static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
995 u32 high_crc = ~(u32)0;
996 u32 low_crc = ~(u32)0;
999 lenum = cpu_to_le64(root_objectid);
1000 high_crc = crc32c(high_crc, &lenum, sizeof(lenum));
1001 lenum = cpu_to_le64(owner);
1002 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
1003 lenum = cpu_to_le64(offset);
1004 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
1006 return ((u64)high_crc << 31) ^ (u64)low_crc;
1009 static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
1010 struct btrfs_extent_data_ref *ref)
1012 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
1013 btrfs_extent_data_ref_objectid(leaf, ref),
1014 btrfs_extent_data_ref_offset(leaf, ref));
1017 static int match_extent_data_ref(struct extent_buffer *leaf,
1018 struct btrfs_extent_data_ref *ref,
1019 u64 root_objectid, u64 owner, u64 offset)
1021 if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
1022 btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
1023 btrfs_extent_data_ref_offset(leaf, ref) != offset)
1028 static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
1029 struct btrfs_root *root,
1030 struct btrfs_path *path,
1031 u64 bytenr, u64 parent,
1033 u64 owner, u64 offset)
1035 struct btrfs_key key;
1036 struct btrfs_extent_data_ref *ref;
1037 struct extent_buffer *leaf;
1043 key.objectid = bytenr;
1045 key.type = BTRFS_SHARED_DATA_REF_KEY;
1046 key.offset = parent;
1048 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1049 key.offset = hash_extent_data_ref(root_objectid,
1054 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1063 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1064 key.type = BTRFS_EXTENT_REF_V0_KEY;
1065 btrfs_release_path(path);
1066 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1077 leaf = path->nodes[0];
1078 nritems = btrfs_header_nritems(leaf);
1080 if (path->slots[0] >= nritems) {
1081 ret = btrfs_next_leaf(root, path);
1087 leaf = path->nodes[0];
1088 nritems = btrfs_header_nritems(leaf);
1092 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1093 if (key.objectid != bytenr ||
1094 key.type != BTRFS_EXTENT_DATA_REF_KEY)
1097 ref = btrfs_item_ptr(leaf, path->slots[0],
1098 struct btrfs_extent_data_ref);
1100 if (match_extent_data_ref(leaf, ref, root_objectid,
1103 btrfs_release_path(path);
1115 static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
1116 struct btrfs_root *root,
1117 struct btrfs_path *path,
1118 u64 bytenr, u64 parent,
1119 u64 root_objectid, u64 owner,
1120 u64 offset, int refs_to_add)
1122 struct btrfs_key key;
1123 struct extent_buffer *leaf;
1128 key.objectid = bytenr;
1130 key.type = BTRFS_SHARED_DATA_REF_KEY;
1131 key.offset = parent;
1132 size = sizeof(struct btrfs_shared_data_ref);
1134 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1135 key.offset = hash_extent_data_ref(root_objectid,
1137 size = sizeof(struct btrfs_extent_data_ref);
1140 ret = btrfs_insert_empty_item(trans, root, path, &key, size);
1141 if (ret && ret != -EEXIST)
1144 leaf = path->nodes[0];
1146 struct btrfs_shared_data_ref *ref;
1147 ref = btrfs_item_ptr(leaf, path->slots[0],
1148 struct btrfs_shared_data_ref);
1150 btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
1152 num_refs = btrfs_shared_data_ref_count(leaf, ref);
1153 num_refs += refs_to_add;
1154 btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
1157 struct btrfs_extent_data_ref *ref;
1158 while (ret == -EEXIST) {
1159 ref = btrfs_item_ptr(leaf, path->slots[0],
1160 struct btrfs_extent_data_ref);
1161 if (match_extent_data_ref(leaf, ref, root_objectid,
1164 btrfs_release_path(path);
1166 ret = btrfs_insert_empty_item(trans, root, path, &key,
1168 if (ret && ret != -EEXIST)
1171 leaf = path->nodes[0];
1173 ref = btrfs_item_ptr(leaf, path->slots[0],
1174 struct btrfs_extent_data_ref);
1176 btrfs_set_extent_data_ref_root(leaf, ref,
1178 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
1179 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
1180 btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
1182 num_refs = btrfs_extent_data_ref_count(leaf, ref);
1183 num_refs += refs_to_add;
1184 btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
1187 btrfs_mark_buffer_dirty(leaf);
1190 btrfs_release_path(path);
1194 static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
1195 struct btrfs_root *root,
1196 struct btrfs_path *path,
1199 struct btrfs_key key;
1200 struct btrfs_extent_data_ref *ref1 = NULL;
1201 struct btrfs_shared_data_ref *ref2 = NULL;
1202 struct extent_buffer *leaf;
1206 leaf = path->nodes[0];
1207 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1209 if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1210 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1211 struct btrfs_extent_data_ref);
1212 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1213 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1214 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1215 struct btrfs_shared_data_ref);
1216 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1217 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1218 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1219 struct btrfs_extent_ref_v0 *ref0;
1220 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1221 struct btrfs_extent_ref_v0);
1222 num_refs = btrfs_ref_count_v0(leaf, ref0);
1228 BUG_ON(num_refs < refs_to_drop);
1229 num_refs -= refs_to_drop;
1231 if (num_refs == 0) {
1232 ret = btrfs_del_item(trans, root, path);
1234 if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
1235 btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
1236 else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
1237 btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
1238 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1240 struct btrfs_extent_ref_v0 *ref0;
1241 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1242 struct btrfs_extent_ref_v0);
1243 btrfs_set_ref_count_v0(leaf, ref0, num_refs);
1246 btrfs_mark_buffer_dirty(leaf);
1251 static noinline u32 extent_data_ref_count(struct btrfs_root *root,
1252 struct btrfs_path *path,
1253 struct btrfs_extent_inline_ref *iref)
1255 struct btrfs_key key;
1256 struct extent_buffer *leaf;
1257 struct btrfs_extent_data_ref *ref1;
1258 struct btrfs_shared_data_ref *ref2;
1261 leaf = path->nodes[0];
1262 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1264 if (btrfs_extent_inline_ref_type(leaf, iref) ==
1265 BTRFS_EXTENT_DATA_REF_KEY) {
1266 ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
1267 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1269 ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
1270 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1272 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1273 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1274 struct btrfs_extent_data_ref);
1275 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1276 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1277 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1278 struct btrfs_shared_data_ref);
1279 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1280 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1281 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1282 struct btrfs_extent_ref_v0 *ref0;
1283 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1284 struct btrfs_extent_ref_v0);
1285 num_refs = btrfs_ref_count_v0(leaf, ref0);
1293 static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
1294 struct btrfs_root *root,
1295 struct btrfs_path *path,
1296 u64 bytenr, u64 parent,
1299 struct btrfs_key key;
1302 key.objectid = bytenr;
1304 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1305 key.offset = parent;
1307 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1308 key.offset = root_objectid;
1311 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1314 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1315 if (ret == -ENOENT && parent) {
1316 btrfs_release_path(path);
1317 key.type = BTRFS_EXTENT_REF_V0_KEY;
1318 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1326 static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
1327 struct btrfs_root *root,
1328 struct btrfs_path *path,
1329 u64 bytenr, u64 parent,
1332 struct btrfs_key key;
1335 key.objectid = bytenr;
1337 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1338 key.offset = parent;
1340 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1341 key.offset = root_objectid;
1344 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1345 btrfs_release_path(path);
1349 static inline int extent_ref_type(u64 parent, u64 owner)
1352 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1354 type = BTRFS_SHARED_BLOCK_REF_KEY;
1356 type = BTRFS_TREE_BLOCK_REF_KEY;
1359 type = BTRFS_SHARED_DATA_REF_KEY;
1361 type = BTRFS_EXTENT_DATA_REF_KEY;
1366 static int find_next_key(struct btrfs_path *path, int level,
1367 struct btrfs_key *key)
1370 for (; level < BTRFS_MAX_LEVEL; level++) {
1371 if (!path->nodes[level])
1373 if (path->slots[level] + 1 >=
1374 btrfs_header_nritems(path->nodes[level]))
1377 btrfs_item_key_to_cpu(path->nodes[level], key,
1378 path->slots[level] + 1);
1380 btrfs_node_key_to_cpu(path->nodes[level], key,
1381 path->slots[level] + 1);
1388 * look for inline back ref. if back ref is found, *ref_ret is set
1389 * to the address of inline back ref, and 0 is returned.
1391 * if back ref isn't found, *ref_ret is set to the address where it
1392 * should be inserted, and -ENOENT is returned.
1394 * if insert is true and there are too many inline back refs, the path
1395 * points to the extent item, and -EAGAIN is returned.
1397 * NOTE: inline back refs are ordered in the same way that back ref
1398 * items in the tree are ordered.
1400 static noinline_for_stack
1401 int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
1402 struct btrfs_root *root,
1403 struct btrfs_path *path,
1404 struct btrfs_extent_inline_ref **ref_ret,
1405 u64 bytenr, u64 num_bytes,
1406 u64 parent, u64 root_objectid,
1407 u64 owner, u64 offset, int insert)
1409 struct btrfs_key key;
1410 struct extent_buffer *leaf;
1411 struct btrfs_extent_item *ei;
1412 struct btrfs_extent_inline_ref *iref;
1423 key.objectid = bytenr;
1424 key.type = BTRFS_EXTENT_ITEM_KEY;
1425 key.offset = num_bytes;
1427 want = extent_ref_type(parent, owner);
1429 extra_size = btrfs_extent_inline_ref_size(want);
1430 path->keep_locks = 1;
1433 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
1440 leaf = path->nodes[0];
1441 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1442 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1443 if (item_size < sizeof(*ei)) {
1448 ret = convert_extent_item_v0(trans, root, path, owner,
1454 leaf = path->nodes[0];
1455 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1458 BUG_ON(item_size < sizeof(*ei));
1460 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1461 flags = btrfs_extent_flags(leaf, ei);
1463 ptr = (unsigned long)(ei + 1);
1464 end = (unsigned long)ei + item_size;
1466 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
1467 ptr += sizeof(struct btrfs_tree_block_info);
1470 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_DATA));
1479 iref = (struct btrfs_extent_inline_ref *)ptr;
1480 type = btrfs_extent_inline_ref_type(leaf, iref);
1484 ptr += btrfs_extent_inline_ref_size(type);
1488 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1489 struct btrfs_extent_data_ref *dref;
1490 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1491 if (match_extent_data_ref(leaf, dref, root_objectid,
1496 if (hash_extent_data_ref_item(leaf, dref) <
1497 hash_extent_data_ref(root_objectid, owner, offset))
1501 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1503 if (parent == ref_offset) {
1507 if (ref_offset < parent)
1510 if (root_objectid == ref_offset) {
1514 if (ref_offset < root_objectid)
1518 ptr += btrfs_extent_inline_ref_size(type);
1520 if (err == -ENOENT && insert) {
1521 if (item_size + extra_size >=
1522 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
1527 * To add new inline back ref, we have to make sure
1528 * there is no corresponding back ref item.
1529 * For simplicity, we just do not add new inline back
1530 * ref if there is any kind of item for this block
1532 if (find_next_key(path, 0, &key) == 0 &&
1533 key.objectid == bytenr &&
1534 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
1539 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
1542 path->keep_locks = 0;
1543 btrfs_unlock_up_safe(path, 1);
1549 * helper to add new inline back ref
1551 static noinline_for_stack
1552 int setup_inline_extent_backref(struct btrfs_trans_handle *trans,
1553 struct btrfs_root *root,
1554 struct btrfs_path *path,
1555 struct btrfs_extent_inline_ref *iref,
1556 u64 parent, u64 root_objectid,
1557 u64 owner, u64 offset, int refs_to_add,
1558 struct btrfs_delayed_extent_op *extent_op)
1560 struct extent_buffer *leaf;
1561 struct btrfs_extent_item *ei;
1564 unsigned long item_offset;
1570 leaf = path->nodes[0];
1571 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1572 item_offset = (unsigned long)iref - (unsigned long)ei;
1574 type = extent_ref_type(parent, owner);
1575 size = btrfs_extent_inline_ref_size(type);
1577 ret = btrfs_extend_item(trans, root, path, size);
1579 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1580 refs = btrfs_extent_refs(leaf, ei);
1581 refs += refs_to_add;
1582 btrfs_set_extent_refs(leaf, ei, refs);
1584 __run_delayed_extent_op(extent_op, leaf, ei);
1586 ptr = (unsigned long)ei + item_offset;
1587 end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
1588 if (ptr < end - size)
1589 memmove_extent_buffer(leaf, ptr + size, ptr,
1592 iref = (struct btrfs_extent_inline_ref *)ptr;
1593 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1594 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1595 struct btrfs_extent_data_ref *dref;
1596 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1597 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1598 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1599 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1600 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1601 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1602 struct btrfs_shared_data_ref *sref;
1603 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1604 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1605 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1606 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1607 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1609 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1611 btrfs_mark_buffer_dirty(leaf);
1615 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1616 struct btrfs_root *root,
1617 struct btrfs_path *path,
1618 struct btrfs_extent_inline_ref **ref_ret,
1619 u64 bytenr, u64 num_bytes, u64 parent,
1620 u64 root_objectid, u64 owner, u64 offset)
1624 ret = lookup_inline_extent_backref(trans, root, path, ref_ret,
1625 bytenr, num_bytes, parent,
1626 root_objectid, owner, offset, 0);
1630 btrfs_release_path(path);
1633 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1634 ret = lookup_tree_block_ref(trans, root, path, bytenr, parent,
1637 ret = lookup_extent_data_ref(trans, root, path, bytenr, parent,
1638 root_objectid, owner, offset);
1644 * helper to update/remove inline back ref
1646 static noinline_for_stack
1647 int update_inline_extent_backref(struct btrfs_trans_handle *trans,
1648 struct btrfs_root *root,
1649 struct btrfs_path *path,
1650 struct btrfs_extent_inline_ref *iref,
1652 struct btrfs_delayed_extent_op *extent_op)
1654 struct extent_buffer *leaf;
1655 struct btrfs_extent_item *ei;
1656 struct btrfs_extent_data_ref *dref = NULL;
1657 struct btrfs_shared_data_ref *sref = NULL;
1666 leaf = path->nodes[0];
1667 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1668 refs = btrfs_extent_refs(leaf, ei);
1669 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1670 refs += refs_to_mod;
1671 btrfs_set_extent_refs(leaf, ei, refs);
1673 __run_delayed_extent_op(extent_op, leaf, ei);
1675 type = btrfs_extent_inline_ref_type(leaf, iref);
1677 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1678 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1679 refs = btrfs_extent_data_ref_count(leaf, dref);
1680 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1681 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1682 refs = btrfs_shared_data_ref_count(leaf, sref);
1685 BUG_ON(refs_to_mod != -1);
1688 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1689 refs += refs_to_mod;
1692 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1693 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1695 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1697 size = btrfs_extent_inline_ref_size(type);
1698 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1699 ptr = (unsigned long)iref;
1700 end = (unsigned long)ei + item_size;
1701 if (ptr + size < end)
1702 memmove_extent_buffer(leaf, ptr, ptr + size,
1705 ret = btrfs_truncate_item(trans, root, path, item_size, 1);
1707 btrfs_mark_buffer_dirty(leaf);
1711 static noinline_for_stack
1712 int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1713 struct btrfs_root *root,
1714 struct btrfs_path *path,
1715 u64 bytenr, u64 num_bytes, u64 parent,
1716 u64 root_objectid, u64 owner,
1717 u64 offset, int refs_to_add,
1718 struct btrfs_delayed_extent_op *extent_op)
1720 struct btrfs_extent_inline_ref *iref;
1723 ret = lookup_inline_extent_backref(trans, root, path, &iref,
1724 bytenr, num_bytes, parent,
1725 root_objectid, owner, offset, 1);
1727 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
1728 ret = update_inline_extent_backref(trans, root, path, iref,
1729 refs_to_add, extent_op);
1730 } else if (ret == -ENOENT) {
1731 ret = setup_inline_extent_backref(trans, root, path, iref,
1732 parent, root_objectid,
1733 owner, offset, refs_to_add,
1739 static int insert_extent_backref(struct btrfs_trans_handle *trans,
1740 struct btrfs_root *root,
1741 struct btrfs_path *path,
1742 u64 bytenr, u64 parent, u64 root_objectid,
1743 u64 owner, u64 offset, int refs_to_add)
1746 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1747 BUG_ON(refs_to_add != 1);
1748 ret = insert_tree_block_ref(trans, root, path, bytenr,
1749 parent, root_objectid);
1751 ret = insert_extent_data_ref(trans, root, path, bytenr,
1752 parent, root_objectid,
1753 owner, offset, refs_to_add);
1758 static int remove_extent_backref(struct btrfs_trans_handle *trans,
1759 struct btrfs_root *root,
1760 struct btrfs_path *path,
1761 struct btrfs_extent_inline_ref *iref,
1762 int refs_to_drop, int is_data)
1766 BUG_ON(!is_data && refs_to_drop != 1);
1768 ret = update_inline_extent_backref(trans, root, path, iref,
1769 -refs_to_drop, NULL);
1770 } else if (is_data) {
1771 ret = remove_extent_data_ref(trans, root, path, refs_to_drop);
1773 ret = btrfs_del_item(trans, root, path);
1778 static int btrfs_issue_discard(struct block_device *bdev,
1781 return blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_NOFS, 0);
1784 static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
1785 u64 num_bytes, u64 *actual_bytes)
1788 u64 discarded_bytes = 0;
1789 struct btrfs_multi_bio *multi = NULL;
1792 /* Tell the block device(s) that the sectors can be discarded */
1793 ret = btrfs_map_block(&root->fs_info->mapping_tree, REQ_DISCARD,
1794 bytenr, &num_bytes, &multi, 0);
1796 struct btrfs_bio_stripe *stripe = multi->stripes;
1800 for (i = 0; i < multi->num_stripes; i++, stripe++) {
1801 if (!stripe->dev->can_discard)
1804 ret = btrfs_issue_discard(stripe->dev->bdev,
1808 discarded_bytes += stripe->length;
1809 else if (ret != -EOPNOTSUPP)
1813 * Just in case we get back EOPNOTSUPP for some reason,
1814 * just ignore the return value so we don't screw up
1815 * people calling discard_extent.
1823 *actual_bytes = discarded_bytes;
1829 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1830 struct btrfs_root *root,
1831 u64 bytenr, u64 num_bytes, u64 parent,
1832 u64 root_objectid, u64 owner, u64 offset)
1835 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID &&
1836 root_objectid == BTRFS_TREE_LOG_OBJECTID);
1838 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1839 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
1840 parent, root_objectid, (int)owner,
1841 BTRFS_ADD_DELAYED_REF, NULL);
1843 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
1844 parent, root_objectid, owner, offset,
1845 BTRFS_ADD_DELAYED_REF, NULL);
1850 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1851 struct btrfs_root *root,
1852 u64 bytenr, u64 num_bytes,
1853 u64 parent, u64 root_objectid,
1854 u64 owner, u64 offset, int refs_to_add,
1855 struct btrfs_delayed_extent_op *extent_op)
1857 struct btrfs_path *path;
1858 struct extent_buffer *leaf;
1859 struct btrfs_extent_item *item;
1864 path = btrfs_alloc_path();
1869 path->leave_spinning = 1;
1870 /* this will setup the path even if it fails to insert the back ref */
1871 ret = insert_inline_extent_backref(trans, root->fs_info->extent_root,
1872 path, bytenr, num_bytes, parent,
1873 root_objectid, owner, offset,
1874 refs_to_add, extent_op);
1878 if (ret != -EAGAIN) {
1883 leaf = path->nodes[0];
1884 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1885 refs = btrfs_extent_refs(leaf, item);
1886 btrfs_set_extent_refs(leaf, item, refs + refs_to_add);
1888 __run_delayed_extent_op(extent_op, leaf, item);
1890 btrfs_mark_buffer_dirty(leaf);
1891 btrfs_release_path(path);
1894 path->leave_spinning = 1;
1896 /* now insert the actual backref */
1897 ret = insert_extent_backref(trans, root->fs_info->extent_root,
1898 path, bytenr, parent, root_objectid,
1899 owner, offset, refs_to_add);
1902 btrfs_free_path(path);
1906 static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
1907 struct btrfs_root *root,
1908 struct btrfs_delayed_ref_node *node,
1909 struct btrfs_delayed_extent_op *extent_op,
1910 int insert_reserved)
1913 struct btrfs_delayed_data_ref *ref;
1914 struct btrfs_key ins;
1919 ins.objectid = node->bytenr;
1920 ins.offset = node->num_bytes;
1921 ins.type = BTRFS_EXTENT_ITEM_KEY;
1923 ref = btrfs_delayed_node_to_data_ref(node);
1924 if (node->type == BTRFS_SHARED_DATA_REF_KEY)
1925 parent = ref->parent;
1927 ref_root = ref->root;
1929 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
1931 BUG_ON(extent_op->update_key);
1932 flags |= extent_op->flags_to_set;
1934 ret = alloc_reserved_file_extent(trans, root,
1935 parent, ref_root, flags,
1936 ref->objectid, ref->offset,
1937 &ins, node->ref_mod);
1938 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
1939 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
1940 node->num_bytes, parent,
1941 ref_root, ref->objectid,
1942 ref->offset, node->ref_mod,
1944 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
1945 ret = __btrfs_free_extent(trans, root, node->bytenr,
1946 node->num_bytes, parent,
1947 ref_root, ref->objectid,
1948 ref->offset, node->ref_mod,
1956 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
1957 struct extent_buffer *leaf,
1958 struct btrfs_extent_item *ei)
1960 u64 flags = btrfs_extent_flags(leaf, ei);
1961 if (extent_op->update_flags) {
1962 flags |= extent_op->flags_to_set;
1963 btrfs_set_extent_flags(leaf, ei, flags);
1966 if (extent_op->update_key) {
1967 struct btrfs_tree_block_info *bi;
1968 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK));
1969 bi = (struct btrfs_tree_block_info *)(ei + 1);
1970 btrfs_set_tree_block_key(leaf, bi, &extent_op->key);
1974 static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
1975 struct btrfs_root *root,
1976 struct btrfs_delayed_ref_node *node,
1977 struct btrfs_delayed_extent_op *extent_op)
1979 struct btrfs_key key;
1980 struct btrfs_path *path;
1981 struct btrfs_extent_item *ei;
1982 struct extent_buffer *leaf;
1987 path = btrfs_alloc_path();
1991 key.objectid = node->bytenr;
1992 key.type = BTRFS_EXTENT_ITEM_KEY;
1993 key.offset = node->num_bytes;
1996 path->leave_spinning = 1;
1997 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key,
2008 leaf = path->nodes[0];
2009 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2010 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2011 if (item_size < sizeof(*ei)) {
2012 ret = convert_extent_item_v0(trans, root->fs_info->extent_root,
2018 leaf = path->nodes[0];
2019 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2022 BUG_ON(item_size < sizeof(*ei));
2023 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2024 __run_delayed_extent_op(extent_op, leaf, ei);
2026 btrfs_mark_buffer_dirty(leaf);
2028 btrfs_free_path(path);
2032 static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
2033 struct btrfs_root *root,
2034 struct btrfs_delayed_ref_node *node,
2035 struct btrfs_delayed_extent_op *extent_op,
2036 int insert_reserved)
2039 struct btrfs_delayed_tree_ref *ref;
2040 struct btrfs_key ins;
2044 ins.objectid = node->bytenr;
2045 ins.offset = node->num_bytes;
2046 ins.type = BTRFS_EXTENT_ITEM_KEY;
2048 ref = btrfs_delayed_node_to_tree_ref(node);
2049 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2050 parent = ref->parent;
2052 ref_root = ref->root;
2054 BUG_ON(node->ref_mod != 1);
2055 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
2056 BUG_ON(!extent_op || !extent_op->update_flags ||
2057 !extent_op->update_key);
2058 ret = alloc_reserved_tree_block(trans, root,
2060 extent_op->flags_to_set,
2063 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
2064 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
2065 node->num_bytes, parent, ref_root,
2066 ref->level, 0, 1, extent_op);
2067 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
2068 ret = __btrfs_free_extent(trans, root, node->bytenr,
2069 node->num_bytes, parent, ref_root,
2070 ref->level, 0, 1, extent_op);
2077 /* helper function to actually process a single delayed ref entry */
2078 static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
2079 struct btrfs_root *root,
2080 struct btrfs_delayed_ref_node *node,
2081 struct btrfs_delayed_extent_op *extent_op,
2082 int insert_reserved)
2085 if (btrfs_delayed_ref_is_head(node)) {
2086 struct btrfs_delayed_ref_head *head;
2088 * we've hit the end of the chain and we were supposed
2089 * to insert this extent into the tree. But, it got
2090 * deleted before we ever needed to insert it, so all
2091 * we have to do is clean up the accounting
2094 head = btrfs_delayed_node_to_head(node);
2095 if (insert_reserved) {
2096 btrfs_pin_extent(root, node->bytenr,
2097 node->num_bytes, 1);
2098 if (head->is_data) {
2099 ret = btrfs_del_csums(trans, root,
2105 mutex_unlock(&head->mutex);
2109 if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
2110 node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2111 ret = run_delayed_tree_ref(trans, root, node, extent_op,
2113 else if (node->type == BTRFS_EXTENT_DATA_REF_KEY ||
2114 node->type == BTRFS_SHARED_DATA_REF_KEY)
2115 ret = run_delayed_data_ref(trans, root, node, extent_op,
2122 static noinline struct btrfs_delayed_ref_node *
2123 select_delayed_ref(struct btrfs_delayed_ref_head *head)
2125 struct rb_node *node;
2126 struct btrfs_delayed_ref_node *ref;
2127 int action = BTRFS_ADD_DELAYED_REF;
2130 * select delayed ref of type BTRFS_ADD_DELAYED_REF first.
2131 * this prevents ref count from going down to zero when
2132 * there still are pending delayed ref.
2134 node = rb_prev(&head->node.rb_node);
2138 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2140 if (ref->bytenr != head->node.bytenr)
2142 if (ref->action == action)
2144 node = rb_prev(node);
2146 if (action == BTRFS_ADD_DELAYED_REF) {
2147 action = BTRFS_DROP_DELAYED_REF;
2153 static noinline int run_clustered_refs(struct btrfs_trans_handle *trans,
2154 struct btrfs_root *root,
2155 struct list_head *cluster)
2157 struct btrfs_delayed_ref_root *delayed_refs;
2158 struct btrfs_delayed_ref_node *ref;
2159 struct btrfs_delayed_ref_head *locked_ref = NULL;
2160 struct btrfs_delayed_extent_op *extent_op;
2163 int must_insert_reserved = 0;
2165 delayed_refs = &trans->transaction->delayed_refs;
2168 /* pick a new head ref from the cluster list */
2169 if (list_empty(cluster))
2172 locked_ref = list_entry(cluster->next,
2173 struct btrfs_delayed_ref_head, cluster);
2175 /* grab the lock that says we are going to process
2176 * all the refs for this head */
2177 ret = btrfs_delayed_ref_lock(trans, locked_ref);
2180 * we may have dropped the spin lock to get the head
2181 * mutex lock, and that might have given someone else
2182 * time to free the head. If that's true, it has been
2183 * removed from our list and we can move on.
2185 if (ret == -EAGAIN) {
2193 * record the must insert reserved flag before we
2194 * drop the spin lock.
2196 must_insert_reserved = locked_ref->must_insert_reserved;
2197 locked_ref->must_insert_reserved = 0;
2199 extent_op = locked_ref->extent_op;
2200 locked_ref->extent_op = NULL;
2203 * locked_ref is the head node, so we have to go one
2204 * node back for any delayed ref updates
2206 ref = select_delayed_ref(locked_ref);
2208 /* All delayed refs have been processed, Go ahead
2209 * and send the head node to run_one_delayed_ref,
2210 * so that any accounting fixes can happen
2212 ref = &locked_ref->node;
2214 if (extent_op && must_insert_reserved) {
2220 spin_unlock(&delayed_refs->lock);
2222 ret = run_delayed_extent_op(trans, root,
2228 spin_lock(&delayed_refs->lock);
2232 list_del_init(&locked_ref->cluster);
2237 rb_erase(&ref->rb_node, &delayed_refs->root);
2238 delayed_refs->num_entries--;
2240 spin_unlock(&delayed_refs->lock);
2242 ret = run_one_delayed_ref(trans, root, ref, extent_op,
2243 must_insert_reserved);
2246 btrfs_put_delayed_ref(ref);
2251 spin_lock(&delayed_refs->lock);
2257 * this starts processing the delayed reference count updates and
2258 * extent insertions we have queued up so far. count can be
2259 * 0, which means to process everything in the tree at the start
2260 * of the run (but not newly added entries), or it can be some target
2261 * number you'd like to process.
2263 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2264 struct btrfs_root *root, unsigned long count)
2266 struct rb_node *node;
2267 struct btrfs_delayed_ref_root *delayed_refs;
2268 struct btrfs_delayed_ref_node *ref;
2269 struct list_head cluster;
2271 int run_all = count == (unsigned long)-1;
2274 if (root == root->fs_info->extent_root)
2275 root = root->fs_info->tree_root;
2277 delayed_refs = &trans->transaction->delayed_refs;
2278 INIT_LIST_HEAD(&cluster);
2280 spin_lock(&delayed_refs->lock);
2282 count = delayed_refs->num_entries * 2;
2286 if (!(run_all || run_most) &&
2287 delayed_refs->num_heads_ready < 64)
2291 * go find something we can process in the rbtree. We start at
2292 * the beginning of the tree, and then build a cluster
2293 * of refs to process starting at the first one we are able to
2296 ret = btrfs_find_ref_cluster(trans, &cluster,
2297 delayed_refs->run_delayed_start);
2301 ret = run_clustered_refs(trans, root, &cluster);
2304 count -= min_t(unsigned long, ret, count);
2311 node = rb_first(&delayed_refs->root);
2314 count = (unsigned long)-1;
2317 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2319 if (btrfs_delayed_ref_is_head(ref)) {
2320 struct btrfs_delayed_ref_head *head;
2322 head = btrfs_delayed_node_to_head(ref);
2323 atomic_inc(&ref->refs);
2325 spin_unlock(&delayed_refs->lock);
2327 * Mutex was contended, block until it's
2328 * released and try again
2330 mutex_lock(&head->mutex);
2331 mutex_unlock(&head->mutex);
2333 btrfs_put_delayed_ref(ref);
2337 node = rb_next(node);
2339 spin_unlock(&delayed_refs->lock);
2340 schedule_timeout(1);
2344 spin_unlock(&delayed_refs->lock);
2348 int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
2349 struct btrfs_root *root,
2350 u64 bytenr, u64 num_bytes, u64 flags,
2353 struct btrfs_delayed_extent_op *extent_op;
2356 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
2360 extent_op->flags_to_set = flags;
2361 extent_op->update_flags = 1;
2362 extent_op->update_key = 0;
2363 extent_op->is_data = is_data ? 1 : 0;
2365 ret = btrfs_add_delayed_extent_op(trans, bytenr, num_bytes, extent_op);
2371 static noinline int check_delayed_ref(struct btrfs_trans_handle *trans,
2372 struct btrfs_root *root,
2373 struct btrfs_path *path,
2374 u64 objectid, u64 offset, u64 bytenr)
2376 struct btrfs_delayed_ref_head *head;
2377 struct btrfs_delayed_ref_node *ref;
2378 struct btrfs_delayed_data_ref *data_ref;
2379 struct btrfs_delayed_ref_root *delayed_refs;
2380 struct rb_node *node;
2384 delayed_refs = &trans->transaction->delayed_refs;
2385 spin_lock(&delayed_refs->lock);
2386 head = btrfs_find_delayed_ref_head(trans, bytenr);
2390 if (!mutex_trylock(&head->mutex)) {
2391 atomic_inc(&head->node.refs);
2392 spin_unlock(&delayed_refs->lock);
2394 btrfs_release_path(path);
2397 * Mutex was contended, block until it's released and let
2400 mutex_lock(&head->mutex);
2401 mutex_unlock(&head->mutex);
2402 btrfs_put_delayed_ref(&head->node);
2406 node = rb_prev(&head->node.rb_node);
2410 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2412 if (ref->bytenr != bytenr)
2416 if (ref->type != BTRFS_EXTENT_DATA_REF_KEY)
2419 data_ref = btrfs_delayed_node_to_data_ref(ref);
2421 node = rb_prev(node);
2423 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2424 if (ref->bytenr == bytenr)
2428 if (data_ref->root != root->root_key.objectid ||
2429 data_ref->objectid != objectid || data_ref->offset != offset)
2434 mutex_unlock(&head->mutex);
2436 spin_unlock(&delayed_refs->lock);
2440 static noinline int check_committed_ref(struct btrfs_trans_handle *trans,
2441 struct btrfs_root *root,
2442 struct btrfs_path *path,
2443 u64 objectid, u64 offset, u64 bytenr)
2445 struct btrfs_root *extent_root = root->fs_info->extent_root;
2446 struct extent_buffer *leaf;
2447 struct btrfs_extent_data_ref *ref;
2448 struct btrfs_extent_inline_ref *iref;
2449 struct btrfs_extent_item *ei;
2450 struct btrfs_key key;
2454 key.objectid = bytenr;
2455 key.offset = (u64)-1;
2456 key.type = BTRFS_EXTENT_ITEM_KEY;
2458 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
2464 if (path->slots[0] == 0)
2468 leaf = path->nodes[0];
2469 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2471 if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY)
2475 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2476 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2477 if (item_size < sizeof(*ei)) {
2478 WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0));
2482 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2484 if (item_size != sizeof(*ei) +
2485 btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY))
2488 if (btrfs_extent_generation(leaf, ei) <=
2489 btrfs_root_last_snapshot(&root->root_item))
2492 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
2493 if (btrfs_extent_inline_ref_type(leaf, iref) !=
2494 BTRFS_EXTENT_DATA_REF_KEY)
2497 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
2498 if (btrfs_extent_refs(leaf, ei) !=
2499 btrfs_extent_data_ref_count(leaf, ref) ||
2500 btrfs_extent_data_ref_root(leaf, ref) !=
2501 root->root_key.objectid ||
2502 btrfs_extent_data_ref_objectid(leaf, ref) != objectid ||
2503 btrfs_extent_data_ref_offset(leaf, ref) != offset)
2511 int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans,
2512 struct btrfs_root *root,
2513 u64 objectid, u64 offset, u64 bytenr)
2515 struct btrfs_path *path;
2519 path = btrfs_alloc_path();
2524 ret = check_committed_ref(trans, root, path, objectid,
2526 if (ret && ret != -ENOENT)
2529 ret2 = check_delayed_ref(trans, root, path, objectid,
2531 } while (ret2 == -EAGAIN);
2533 if (ret2 && ret2 != -ENOENT) {
2538 if (ret != -ENOENT || ret2 != -ENOENT)
2541 btrfs_free_path(path);
2542 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
2547 static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
2548 struct btrfs_root *root,
2549 struct extent_buffer *buf,
2550 int full_backref, int inc)
2557 struct btrfs_key key;
2558 struct btrfs_file_extent_item *fi;
2562 int (*process_func)(struct btrfs_trans_handle *, struct btrfs_root *,
2563 u64, u64, u64, u64, u64, u64);
2565 ref_root = btrfs_header_owner(buf);
2566 nritems = btrfs_header_nritems(buf);
2567 level = btrfs_header_level(buf);
2569 if (!root->ref_cows && level == 0)
2573 process_func = btrfs_inc_extent_ref;
2575 process_func = btrfs_free_extent;
2578 parent = buf->start;
2582 for (i = 0; i < nritems; i++) {
2584 btrfs_item_key_to_cpu(buf, &key, i);
2585 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2587 fi = btrfs_item_ptr(buf, i,
2588 struct btrfs_file_extent_item);
2589 if (btrfs_file_extent_type(buf, fi) ==
2590 BTRFS_FILE_EXTENT_INLINE)
2592 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2596 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
2597 key.offset -= btrfs_file_extent_offset(buf, fi);
2598 ret = process_func(trans, root, bytenr, num_bytes,
2599 parent, ref_root, key.objectid,
2604 bytenr = btrfs_node_blockptr(buf, i);
2605 num_bytes = btrfs_level_size(root, level - 1);
2606 ret = process_func(trans, root, bytenr, num_bytes,
2607 parent, ref_root, level - 1, 0);
2618 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2619 struct extent_buffer *buf, int full_backref)
2621 return __btrfs_mod_ref(trans, root, buf, full_backref, 1);
2624 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2625 struct extent_buffer *buf, int full_backref)
2627 return __btrfs_mod_ref(trans, root, buf, full_backref, 0);
2630 static int write_one_cache_group(struct btrfs_trans_handle *trans,
2631 struct btrfs_root *root,
2632 struct btrfs_path *path,
2633 struct btrfs_block_group_cache *cache)
2636 struct btrfs_root *extent_root = root->fs_info->extent_root;
2638 struct extent_buffer *leaf;
2640 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
2645 leaf = path->nodes[0];
2646 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
2647 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
2648 btrfs_mark_buffer_dirty(leaf);
2649 btrfs_release_path(path);
2657 static struct btrfs_block_group_cache *
2658 next_block_group(struct btrfs_root *root,
2659 struct btrfs_block_group_cache *cache)
2661 struct rb_node *node;
2662 spin_lock(&root->fs_info->block_group_cache_lock);
2663 node = rb_next(&cache->cache_node);
2664 btrfs_put_block_group(cache);
2666 cache = rb_entry(node, struct btrfs_block_group_cache,
2668 btrfs_get_block_group(cache);
2671 spin_unlock(&root->fs_info->block_group_cache_lock);
2675 static int cache_save_setup(struct btrfs_block_group_cache *block_group,
2676 struct btrfs_trans_handle *trans,
2677 struct btrfs_path *path)
2679 struct btrfs_root *root = block_group->fs_info->tree_root;
2680 struct inode *inode = NULL;
2682 int dcs = BTRFS_DC_ERROR;
2688 * If this block group is smaller than 100 megs don't bother caching the
2691 if (block_group->key.offset < (100 * 1024 * 1024)) {
2692 spin_lock(&block_group->lock);
2693 block_group->disk_cache_state = BTRFS_DC_WRITTEN;
2694 spin_unlock(&block_group->lock);
2699 inode = lookup_free_space_inode(root, block_group, path);
2700 if (IS_ERR(inode) && PTR_ERR(inode) != -ENOENT) {
2701 ret = PTR_ERR(inode);
2702 btrfs_release_path(path);
2706 if (IS_ERR(inode)) {
2710 if (block_group->ro)
2713 ret = create_free_space_inode(root, trans, block_group, path);
2720 * We want to set the generation to 0, that way if anything goes wrong
2721 * from here on out we know not to trust this cache when we load up next
2724 BTRFS_I(inode)->generation = 0;
2725 ret = btrfs_update_inode(trans, root, inode);
2728 if (i_size_read(inode) > 0) {
2729 ret = btrfs_truncate_free_space_cache(root, trans, path,
2735 spin_lock(&block_group->lock);
2736 if (block_group->cached != BTRFS_CACHE_FINISHED) {
2737 /* We're not cached, don't bother trying to write stuff out */
2738 dcs = BTRFS_DC_WRITTEN;
2739 spin_unlock(&block_group->lock);
2742 spin_unlock(&block_group->lock);
2744 num_pages = (int)div64_u64(block_group->key.offset, 1024 * 1024 * 1024);
2749 * Just to make absolutely sure we have enough space, we're going to
2750 * preallocate 12 pages worth of space for each block group. In
2751 * practice we ought to use at most 8, but we need extra space so we can
2752 * add our header and have a terminator between the extents and the
2756 num_pages *= PAGE_CACHE_SIZE;
2758 ret = btrfs_check_data_free_space(inode, num_pages);
2762 ret = btrfs_prealloc_file_range_trans(inode, trans, 0, 0, num_pages,
2763 num_pages, num_pages,
2766 dcs = BTRFS_DC_SETUP;
2767 btrfs_free_reserved_data_space(inode, num_pages);
2771 btrfs_release_path(path);
2773 spin_lock(&block_group->lock);
2774 block_group->disk_cache_state = dcs;
2775 spin_unlock(&block_group->lock);
2780 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
2781 struct btrfs_root *root)
2783 struct btrfs_block_group_cache *cache;
2785 struct btrfs_path *path;
2788 path = btrfs_alloc_path();
2794 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2796 if (cache->disk_cache_state == BTRFS_DC_CLEAR)
2798 cache = next_block_group(root, cache);
2806 err = cache_save_setup(cache, trans, path);
2807 last = cache->key.objectid + cache->key.offset;
2808 btrfs_put_block_group(cache);
2813 err = btrfs_run_delayed_refs(trans, root,
2818 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2820 if (cache->disk_cache_state == BTRFS_DC_CLEAR) {
2821 btrfs_put_block_group(cache);
2827 cache = next_block_group(root, cache);
2836 if (cache->disk_cache_state == BTRFS_DC_SETUP)
2837 cache->disk_cache_state = BTRFS_DC_NEED_WRITE;
2839 last = cache->key.objectid + cache->key.offset;
2841 err = write_one_cache_group(trans, root, path, cache);
2843 btrfs_put_block_group(cache);
2848 * I don't think this is needed since we're just marking our
2849 * preallocated extent as written, but just in case it can't
2853 err = btrfs_run_delayed_refs(trans, root,
2858 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2861 * Really this shouldn't happen, but it could if we
2862 * couldn't write the entire preallocated extent and
2863 * splitting the extent resulted in a new block.
2866 btrfs_put_block_group(cache);
2869 if (cache->disk_cache_state == BTRFS_DC_NEED_WRITE)
2871 cache = next_block_group(root, cache);
2880 btrfs_write_out_cache(root, trans, cache, path);
2883 * If we didn't have an error then the cache state is still
2884 * NEED_WRITE, so we can set it to WRITTEN.
2886 if (cache->disk_cache_state == BTRFS_DC_NEED_WRITE)
2887 cache->disk_cache_state = BTRFS_DC_WRITTEN;
2888 last = cache->key.objectid + cache->key.offset;
2889 btrfs_put_block_group(cache);
2892 btrfs_free_path(path);
2896 int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr)
2898 struct btrfs_block_group_cache *block_group;
2901 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
2902 if (!block_group || block_group->ro)
2905 btrfs_put_block_group(block_group);
2909 static int update_space_info(struct btrfs_fs_info *info, u64 flags,
2910 u64 total_bytes, u64 bytes_used,
2911 struct btrfs_space_info **space_info)
2913 struct btrfs_space_info *found;
2917 if (flags & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
2918 BTRFS_BLOCK_GROUP_RAID10))
2923 found = __find_space_info(info, flags);
2925 spin_lock(&found->lock);
2926 found->total_bytes += total_bytes;
2927 found->disk_total += total_bytes * factor;
2928 found->bytes_used += bytes_used;
2929 found->disk_used += bytes_used * factor;
2931 spin_unlock(&found->lock);
2932 *space_info = found;
2935 found = kzalloc(sizeof(*found), GFP_NOFS);
2939 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
2940 INIT_LIST_HEAD(&found->block_groups[i]);
2941 init_rwsem(&found->groups_sem);
2942 spin_lock_init(&found->lock);
2943 found->flags = flags & (BTRFS_BLOCK_GROUP_DATA |
2944 BTRFS_BLOCK_GROUP_SYSTEM |
2945 BTRFS_BLOCK_GROUP_METADATA);
2946 found->total_bytes = total_bytes;
2947 found->disk_total = total_bytes * factor;
2948 found->bytes_used = bytes_used;
2949 found->disk_used = bytes_used * factor;
2950 found->bytes_pinned = 0;
2951 found->bytes_reserved = 0;
2952 found->bytes_readonly = 0;
2953 found->bytes_may_use = 0;
2955 found->force_alloc = CHUNK_ALLOC_NO_FORCE;
2956 found->chunk_alloc = 0;
2958 init_waitqueue_head(&found->wait);
2959 *space_info = found;
2960 list_add_rcu(&found->list, &info->space_info);
2964 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
2966 u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 |
2967 BTRFS_BLOCK_GROUP_RAID1 |
2968 BTRFS_BLOCK_GROUP_RAID10 |
2969 BTRFS_BLOCK_GROUP_DUP);
2971 if (flags & BTRFS_BLOCK_GROUP_DATA)
2972 fs_info->avail_data_alloc_bits |= extra_flags;
2973 if (flags & BTRFS_BLOCK_GROUP_METADATA)
2974 fs_info->avail_metadata_alloc_bits |= extra_flags;
2975 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
2976 fs_info->avail_system_alloc_bits |= extra_flags;
2980 u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
2983 * we add in the count of missing devices because we want
2984 * to make sure that any RAID levels on a degraded FS
2985 * continue to be honored.
2987 u64 num_devices = root->fs_info->fs_devices->rw_devices +
2988 root->fs_info->fs_devices->missing_devices;
2990 if (num_devices == 1)
2991 flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0);
2992 if (num_devices < 4)
2993 flags &= ~BTRFS_BLOCK_GROUP_RAID10;
2995 if ((flags & BTRFS_BLOCK_GROUP_DUP) &&
2996 (flags & (BTRFS_BLOCK_GROUP_RAID1 |
2997 BTRFS_BLOCK_GROUP_RAID10))) {
2998 flags &= ~BTRFS_BLOCK_GROUP_DUP;
3001 if ((flags & BTRFS_BLOCK_GROUP_RAID1) &&
3002 (flags & BTRFS_BLOCK_GROUP_RAID10)) {
3003 flags &= ~BTRFS_BLOCK_GROUP_RAID1;
3006 if ((flags & BTRFS_BLOCK_GROUP_RAID0) &&
3007 ((flags & BTRFS_BLOCK_GROUP_RAID1) |
3008 (flags & BTRFS_BLOCK_GROUP_RAID10) |
3009 (flags & BTRFS_BLOCK_GROUP_DUP)))
3010 flags &= ~BTRFS_BLOCK_GROUP_RAID0;
3014 static u64 get_alloc_profile(struct btrfs_root *root, u64 flags)
3016 if (flags & BTRFS_BLOCK_GROUP_DATA)
3017 flags |= root->fs_info->avail_data_alloc_bits &
3018 root->fs_info->data_alloc_profile;
3019 else if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
3020 flags |= root->fs_info->avail_system_alloc_bits &
3021 root->fs_info->system_alloc_profile;
3022 else if (flags & BTRFS_BLOCK_GROUP_METADATA)
3023 flags |= root->fs_info->avail_metadata_alloc_bits &
3024 root->fs_info->metadata_alloc_profile;
3025 return btrfs_reduce_alloc_profile(root, flags);
3028 u64 btrfs_get_alloc_profile(struct btrfs_root *root, int data)
3033 flags = BTRFS_BLOCK_GROUP_DATA;
3034 else if (root == root->fs_info->chunk_root)
3035 flags = BTRFS_BLOCK_GROUP_SYSTEM;
3037 flags = BTRFS_BLOCK_GROUP_METADATA;
3039 return get_alloc_profile(root, flags);
3042 void btrfs_set_inode_space_info(struct btrfs_root *root, struct inode *inode)
3044 BTRFS_I(inode)->space_info = __find_space_info(root->fs_info,
3045 BTRFS_BLOCK_GROUP_DATA);
3049 * This will check the space that the inode allocates from to make sure we have
3050 * enough space for bytes.
3052 int btrfs_check_data_free_space(struct inode *inode, u64 bytes)
3054 struct btrfs_space_info *data_sinfo;
3055 struct btrfs_root *root = BTRFS_I(inode)->root;
3057 int ret = 0, committed = 0, alloc_chunk = 1;
3059 /* make sure bytes are sectorsize aligned */
3060 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3062 if (root == root->fs_info->tree_root ||
3063 BTRFS_I(inode)->location.objectid == BTRFS_FREE_INO_OBJECTID) {
3068 data_sinfo = BTRFS_I(inode)->space_info;
3073 /* make sure we have enough space to handle the data first */
3074 spin_lock(&data_sinfo->lock);
3075 used = data_sinfo->bytes_used + data_sinfo->bytes_reserved +
3076 data_sinfo->bytes_pinned + data_sinfo->bytes_readonly +
3077 data_sinfo->bytes_may_use;
3079 if (used + bytes > data_sinfo->total_bytes) {
3080 struct btrfs_trans_handle *trans;
3083 * if we don't have enough free bytes in this space then we need
3084 * to alloc a new chunk.
3086 if (!data_sinfo->full && alloc_chunk) {
3089 data_sinfo->force_alloc = CHUNK_ALLOC_FORCE;
3090 spin_unlock(&data_sinfo->lock);
3092 alloc_target = btrfs_get_alloc_profile(root, 1);
3093 trans = btrfs_join_transaction(root);
3095 return PTR_ERR(trans);
3097 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
3098 bytes + 2 * 1024 * 1024,
3100 CHUNK_ALLOC_NO_FORCE);
3101 btrfs_end_transaction(trans, root);
3110 btrfs_set_inode_space_info(root, inode);
3111 data_sinfo = BTRFS_I(inode)->space_info;
3117 * If we have less pinned bytes than we want to allocate then
3118 * don't bother committing the transaction, it won't help us.
3120 if (data_sinfo->bytes_pinned < bytes)
3122 spin_unlock(&data_sinfo->lock);
3124 /* commit the current transaction and try again */
3127 !atomic_read(&root->fs_info->open_ioctl_trans)) {
3129 trans = btrfs_join_transaction(root);
3131 return PTR_ERR(trans);
3132 ret = btrfs_commit_transaction(trans, root);
3140 data_sinfo->bytes_may_use += bytes;
3141 spin_unlock(&data_sinfo->lock);
3147 * Called if we need to clear a data reservation for this inode.
3149 void btrfs_free_reserved_data_space(struct inode *inode, u64 bytes)
3151 struct btrfs_root *root = BTRFS_I(inode)->root;
3152 struct btrfs_space_info *data_sinfo;
3154 /* make sure bytes are sectorsize aligned */
3155 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3157 data_sinfo = BTRFS_I(inode)->space_info;
3158 spin_lock(&data_sinfo->lock);
3159 data_sinfo->bytes_may_use -= bytes;
3160 spin_unlock(&data_sinfo->lock);
3163 static void force_metadata_allocation(struct btrfs_fs_info *info)
3165 struct list_head *head = &info->space_info;
3166 struct btrfs_space_info *found;
3169 list_for_each_entry_rcu(found, head, list) {
3170 if (found->flags & BTRFS_BLOCK_GROUP_METADATA)
3171 found->force_alloc = CHUNK_ALLOC_FORCE;
3176 static int should_alloc_chunk(struct btrfs_root *root,
3177 struct btrfs_space_info *sinfo, u64 alloc_bytes,
3180 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
3181 u64 num_bytes = sinfo->total_bytes - sinfo->bytes_readonly;
3182 u64 num_allocated = sinfo->bytes_used + sinfo->bytes_reserved;
3185 if (force == CHUNK_ALLOC_FORCE)
3189 * We need to take into account the global rsv because for all intents
3190 * and purposes it's used space. Don't worry about locking the
3191 * global_rsv, it doesn't change except when the transaction commits.
3193 num_allocated += global_rsv->size;
3196 * in limited mode, we want to have some free space up to
3197 * about 1% of the FS size.
3199 if (force == CHUNK_ALLOC_LIMITED) {
3200 thresh = btrfs_super_total_bytes(&root->fs_info->super_copy);
3201 thresh = max_t(u64, 64 * 1024 * 1024,
3202 div_factor_fine(thresh, 1));
3204 if (num_bytes - num_allocated < thresh)
3209 * we have two similar checks here, one based on percentage
3210 * and once based on a hard number of 256MB. The idea
3211 * is that if we have a good amount of free
3212 * room, don't allocate a chunk. A good mount is
3213 * less than 80% utilized of the chunks we have allocated,
3214 * or more than 256MB free
3216 if (num_allocated + alloc_bytes + 256 * 1024 * 1024 < num_bytes)
3219 if (num_allocated + alloc_bytes < div_factor(num_bytes, 8))
3222 thresh = btrfs_super_total_bytes(&root->fs_info->super_copy);
3224 /* 256MB or 5% of the FS */
3225 thresh = max_t(u64, 256 * 1024 * 1024, div_factor_fine(thresh, 5));
3227 if (num_bytes > thresh && sinfo->bytes_used < div_factor(num_bytes, 3))
3232 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
3233 struct btrfs_root *extent_root, u64 alloc_bytes,
3234 u64 flags, int force)
3236 struct btrfs_space_info *space_info;
3237 struct btrfs_fs_info *fs_info = extent_root->fs_info;
3238 int wait_for_alloc = 0;
3241 flags = btrfs_reduce_alloc_profile(extent_root, flags);
3243 space_info = __find_space_info(extent_root->fs_info, flags);
3245 ret = update_space_info(extent_root->fs_info, flags,
3249 BUG_ON(!space_info);
3252 spin_lock(&space_info->lock);
3253 if (space_info->force_alloc)
3254 force = space_info->force_alloc;
3255 if (space_info->full) {
3256 spin_unlock(&space_info->lock);
3260 if (!should_alloc_chunk(extent_root, space_info, alloc_bytes, force)) {
3261 spin_unlock(&space_info->lock);
3263 } else if (space_info->chunk_alloc) {
3266 space_info->chunk_alloc = 1;
3269 spin_unlock(&space_info->lock);
3271 mutex_lock(&fs_info->chunk_mutex);
3274 * The chunk_mutex is held throughout the entirety of a chunk
3275 * allocation, so once we've acquired the chunk_mutex we know that the
3276 * other guy is done and we need to recheck and see if we should
3279 if (wait_for_alloc) {
3280 mutex_unlock(&fs_info->chunk_mutex);
3286 * If we have mixed data/metadata chunks we want to make sure we keep
3287 * allocating mixed chunks instead of individual chunks.
3289 if (btrfs_mixed_space_info(space_info))
3290 flags |= (BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA);
3293 * if we're doing a data chunk, go ahead and make sure that
3294 * we keep a reasonable number of metadata chunks allocated in the
3297 if (flags & BTRFS_BLOCK_GROUP_DATA && fs_info->metadata_ratio) {
3298 fs_info->data_chunk_allocations++;
3299 if (!(fs_info->data_chunk_allocations %
3300 fs_info->metadata_ratio))
3301 force_metadata_allocation(fs_info);
3304 ret = btrfs_alloc_chunk(trans, extent_root, flags);
3305 if (ret < 0 && ret != -ENOSPC)
3308 spin_lock(&space_info->lock);
3310 space_info->full = 1;
3314 space_info->force_alloc = CHUNK_ALLOC_NO_FORCE;
3315 space_info->chunk_alloc = 0;
3316 spin_unlock(&space_info->lock);
3318 mutex_unlock(&extent_root->fs_info->chunk_mutex);
3323 * shrink metadata reservation for delalloc
3325 static int shrink_delalloc(struct btrfs_trans_handle *trans,
3326 struct btrfs_root *root, u64 to_reclaim, int sync)
3328 struct btrfs_block_rsv *block_rsv;
3329 struct btrfs_space_info *space_info;
3334 int nr_pages = (2 * 1024 * 1024) >> PAGE_CACHE_SHIFT;
3336 unsigned long progress;
3338 block_rsv = &root->fs_info->delalloc_block_rsv;
3339 space_info = block_rsv->space_info;
3342 reserved = space_info->bytes_may_use;
3343 progress = space_info->reservation_progress;
3349 if (root->fs_info->delalloc_bytes == 0) {
3352 btrfs_wait_ordered_extents(root, 0, 0);
3356 max_reclaim = min(reserved, to_reclaim);
3358 while (loops < 1024) {
3359 /* have the flusher threads jump in and do some IO */
3361 nr_pages = min_t(unsigned long, nr_pages,
3362 root->fs_info->delalloc_bytes >> PAGE_CACHE_SHIFT);
3363 writeback_inodes_sb_nr_if_idle(root->fs_info->sb, nr_pages);
3365 spin_lock(&space_info->lock);
3366 if (reserved > space_info->bytes_may_use)
3367 reclaimed += reserved - space_info->bytes_may_use;
3368 reserved = space_info->bytes_may_use;
3369 spin_unlock(&space_info->lock);
3373 if (reserved == 0 || reclaimed >= max_reclaim)
3376 if (trans && trans->transaction->blocked)
3379 time_left = schedule_timeout_interruptible(1);
3381 /* We were interrupted, exit */
3385 /* we've kicked the IO a few times, if anything has been freed,
3386 * exit. There is no sense in looping here for a long time
3387 * when we really need to commit the transaction, or there are
3388 * just too many writers without enough free space
3393 if (progress != space_info->reservation_progress)
3398 if (reclaimed >= to_reclaim && !trans)
3399 btrfs_wait_ordered_extents(root, 0, 0);
3400 return reclaimed >= to_reclaim;
3404 * Retries tells us how many times we've called reserve_metadata_bytes. The
3405 * idea is if this is the first call (retries == 0) then we will add to our
3406 * reserved count if we can't make the allocation in order to hold our place
3407 * while we go and try and free up space. That way for retries > 1 we don't try
3408 * and add space, we just check to see if the amount of unused space is >= the
3409 * total space, meaning that our reservation is valid.
3411 * However if we don't intend to retry this reservation, pass -1 as retries so
3412 * that it short circuits this logic.
3414 static int reserve_metadata_bytes(struct btrfs_trans_handle *trans,
3415 struct btrfs_root *root,
3416 struct btrfs_block_rsv *block_rsv,
3417 u64 orig_bytes, int flush)
3419 struct btrfs_space_info *space_info = block_rsv->space_info;
3421 u64 num_bytes = orig_bytes;
3424 bool committed = false;
3425 bool flushing = false;
3428 spin_lock(&space_info->lock);
3430 * We only want to wait if somebody other than us is flushing and we are
3431 * actually alloed to flush.
3433 while (flush && !flushing && space_info->flush) {
3434 spin_unlock(&space_info->lock);
3436 * If we have a trans handle we can't wait because the flusher
3437 * may have to commit the transaction, which would mean we would
3438 * deadlock since we are waiting for the flusher to finish, but
3439 * hold the current transaction open.
3443 ret = wait_event_interruptible(space_info->wait,
3444 !space_info->flush);
3445 /* Must have been interrupted, return */
3449 spin_lock(&space_info->lock);
3453 unused = space_info->bytes_used + space_info->bytes_reserved +
3454 space_info->bytes_pinned + space_info->bytes_readonly +
3455 space_info->bytes_may_use;
3458 * The idea here is that we've not already over-reserved the block group
3459 * then we can go ahead and save our reservation first and then start
3460 * flushing if we need to. Otherwise if we've already overcommitted
3461 * lets start flushing stuff first and then come back and try to make
3464 if (unused <= space_info->total_bytes) {
3465 unused = space_info->total_bytes - unused;
3466 if (unused >= num_bytes) {
3467 space_info->bytes_may_use += orig_bytes;
3471 * Ok set num_bytes to orig_bytes since we aren't
3472 * overocmmitted, this way we only try and reclaim what
3475 num_bytes = orig_bytes;
3479 * Ok we're over committed, set num_bytes to the overcommitted
3480 * amount plus the amount of bytes that we need for this
3483 num_bytes = unused - space_info->total_bytes +
3484 (orig_bytes * (retries + 1));
3488 * Couldn't make our reservation, save our place so while we're trying
3489 * to reclaim space we can actually use it instead of somebody else
3490 * stealing it from us.
3494 space_info->flush = 1;
3497 spin_unlock(&space_info->lock);
3503 * We do synchronous shrinking since we don't actually unreserve
3504 * metadata until after the IO is completed.
3506 ret = shrink_delalloc(trans, root, num_bytes, 1);
3513 * So if we were overcommitted it's possible that somebody else flushed
3514 * out enough space and we simply didn't have enough space to reclaim,
3515 * so go back around and try again.
3523 * Not enough space to be reclaimed, don't bother committing the
3526 spin_lock(&space_info->lock);
3527 if (space_info->bytes_pinned < orig_bytes)
3529 spin_unlock(&space_info->lock);
3541 trans = btrfs_join_transaction(root);
3544 ret = btrfs_commit_transaction(trans, root);
3553 spin_lock(&space_info->lock);
3554 space_info->flush = 0;
3555 wake_up_all(&space_info->wait);
3556 spin_unlock(&space_info->lock);
3561 static struct btrfs_block_rsv *get_block_rsv(struct btrfs_trans_handle *trans,
3562 struct btrfs_root *root)
3564 struct btrfs_block_rsv *block_rsv;
3566 block_rsv = trans->block_rsv;
3568 block_rsv = root->block_rsv;
3571 block_rsv = &root->fs_info->empty_block_rsv;
3576 static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
3580 spin_lock(&block_rsv->lock);
3581 if (block_rsv->reserved >= num_bytes) {
3582 block_rsv->reserved -= num_bytes;
3583 if (block_rsv->reserved < block_rsv->size)
3584 block_rsv->full = 0;
3587 spin_unlock(&block_rsv->lock);
3591 static void block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
3592 u64 num_bytes, int update_size)
3594 spin_lock(&block_rsv->lock);
3595 block_rsv->reserved += num_bytes;
3597 block_rsv->size += num_bytes;
3598 else if (block_rsv->reserved >= block_rsv->size)
3599 block_rsv->full = 1;
3600 spin_unlock(&block_rsv->lock);
3603 static void block_rsv_release_bytes(struct btrfs_block_rsv *block_rsv,
3604 struct btrfs_block_rsv *dest, u64 num_bytes)
3606 struct btrfs_space_info *space_info = block_rsv->space_info;
3608 spin_lock(&block_rsv->lock);
3609 if (num_bytes == (u64)-1)
3610 num_bytes = block_rsv->size;
3611 block_rsv->size -= num_bytes;
3612 if (block_rsv->reserved >= block_rsv->size) {
3613 num_bytes = block_rsv->reserved - block_rsv->size;
3614 block_rsv->reserved = block_rsv->size;
3615 block_rsv->full = 1;
3619 spin_unlock(&block_rsv->lock);
3621 if (num_bytes > 0) {
3623 spin_lock(&dest->lock);
3627 bytes_to_add = dest->size - dest->reserved;
3628 bytes_to_add = min(num_bytes, bytes_to_add);
3629 dest->reserved += bytes_to_add;
3630 if (dest->reserved >= dest->size)
3632 num_bytes -= bytes_to_add;
3634 spin_unlock(&dest->lock);
3637 spin_lock(&space_info->lock);
3638 space_info->bytes_may_use -= num_bytes;
3639 space_info->reservation_progress++;
3640 spin_unlock(&space_info->lock);
3645 static int block_rsv_migrate_bytes(struct btrfs_block_rsv *src,
3646 struct btrfs_block_rsv *dst, u64 num_bytes)
3650 ret = block_rsv_use_bytes(src, num_bytes);
3654 block_rsv_add_bytes(dst, num_bytes, 1);
3658 void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv)
3660 memset(rsv, 0, sizeof(*rsv));
3661 spin_lock_init(&rsv->lock);
3664 struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_root *root)
3666 struct btrfs_block_rsv *block_rsv;
3667 struct btrfs_fs_info *fs_info = root->fs_info;
3669 block_rsv = kmalloc(sizeof(*block_rsv), GFP_NOFS);
3673 btrfs_init_block_rsv(block_rsv);
3674 block_rsv->space_info = __find_space_info(fs_info,
3675 BTRFS_BLOCK_GROUP_METADATA);
3679 void btrfs_free_block_rsv(struct btrfs_root *root,
3680 struct btrfs_block_rsv *rsv)
3682 btrfs_block_rsv_release(root, rsv, (u64)-1);
3686 int btrfs_block_rsv_add(struct btrfs_trans_handle *trans,
3687 struct btrfs_root *root,
3688 struct btrfs_block_rsv *block_rsv,
3696 ret = reserve_metadata_bytes(trans, root, block_rsv, num_bytes, 1);
3698 block_rsv_add_bytes(block_rsv, num_bytes, 1);
3705 int btrfs_block_rsv_check(struct btrfs_trans_handle *trans,
3706 struct btrfs_root *root,
3707 struct btrfs_block_rsv *block_rsv,
3708 u64 min_reserved, int min_factor)
3716 spin_lock(&block_rsv->lock);
3718 num_bytes = div_factor(block_rsv->size, min_factor);
3719 if (min_reserved > num_bytes)
3720 num_bytes = min_reserved;
3722 if (block_rsv->reserved >= num_bytes)
3725 num_bytes -= block_rsv->reserved;
3726 spin_unlock(&block_rsv->lock);
3731 ret = reserve_metadata_bytes(trans, root, block_rsv, num_bytes, 0);
3733 block_rsv_add_bytes(block_rsv, num_bytes, 0);
3740 int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,
3741 struct btrfs_block_rsv *dst_rsv,
3744 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3747 void btrfs_block_rsv_release(struct btrfs_root *root,
3748 struct btrfs_block_rsv *block_rsv,
3751 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
3752 if (global_rsv->full || global_rsv == block_rsv ||
3753 block_rsv->space_info != global_rsv->space_info)
3755 block_rsv_release_bytes(block_rsv, global_rsv, num_bytes);
3759 * helper to calculate size of global block reservation.
3760 * the desired value is sum of space used by extent tree,
3761 * checksum tree and root tree
3763 static u64 calc_global_metadata_size(struct btrfs_fs_info *fs_info)
3765 struct btrfs_space_info *sinfo;
3769 int csum_size = btrfs_super_csum_size(&fs_info->super_copy);
3771 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_DATA);
3772 spin_lock(&sinfo->lock);
3773 data_used = sinfo->bytes_used;
3774 spin_unlock(&sinfo->lock);
3776 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
3777 spin_lock(&sinfo->lock);
3778 if (sinfo->flags & BTRFS_BLOCK_GROUP_DATA)
3780 meta_used = sinfo->bytes_used;
3781 spin_unlock(&sinfo->lock);
3783 num_bytes = (data_used >> fs_info->sb->s_blocksize_bits) *
3785 num_bytes += div64_u64(data_used + meta_used, 50);
3787 if (num_bytes * 3 > meta_used)
3788 num_bytes = div64_u64(meta_used, 3);
3790 return ALIGN(num_bytes, fs_info->extent_root->leafsize << 10);
3793 static void update_global_block_rsv(struct btrfs_fs_info *fs_info)
3795 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
3796 struct btrfs_space_info *sinfo = block_rsv->space_info;
3799 num_bytes = calc_global_metadata_size(fs_info);
3801 spin_lock(&block_rsv->lock);
3802 spin_lock(&sinfo->lock);
3804 block_rsv->size = num_bytes;
3806 num_bytes = sinfo->bytes_used + sinfo->bytes_pinned +
3807 sinfo->bytes_reserved + sinfo->bytes_readonly +
3808 sinfo->bytes_may_use;
3810 if (sinfo->total_bytes > num_bytes) {
3811 num_bytes = sinfo->total_bytes - num_bytes;
3812 block_rsv->reserved += num_bytes;
3813 sinfo->bytes_may_use += num_bytes;
3816 if (block_rsv->reserved >= block_rsv->size) {
3817 num_bytes = block_rsv->reserved - block_rsv->size;
3818 sinfo->bytes_may_use -= num_bytes;
3819 sinfo->reservation_progress++;
3820 block_rsv->reserved = block_rsv->size;
3821 block_rsv->full = 1;
3824 spin_unlock(&sinfo->lock);
3825 spin_unlock(&block_rsv->lock);
3828 static void init_global_block_rsv(struct btrfs_fs_info *fs_info)
3830 struct btrfs_space_info *space_info;
3832 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
3833 fs_info->chunk_block_rsv.space_info = space_info;
3835 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
3836 fs_info->global_block_rsv.space_info = space_info;
3837 fs_info->delalloc_block_rsv.space_info = space_info;
3838 fs_info->trans_block_rsv.space_info = space_info;
3839 fs_info->empty_block_rsv.space_info = space_info;
3841 fs_info->extent_root->block_rsv = &fs_info->global_block_rsv;
3842 fs_info->csum_root->block_rsv = &fs_info->global_block_rsv;
3843 fs_info->dev_root->block_rsv = &fs_info->global_block_rsv;
3844 fs_info->tree_root->block_rsv = &fs_info->global_block_rsv;
3845 fs_info->chunk_root->block_rsv = &fs_info->chunk_block_rsv;
3847 update_global_block_rsv(fs_info);
3850 static void release_global_block_rsv(struct btrfs_fs_info *fs_info)
3852 block_rsv_release_bytes(&fs_info->global_block_rsv, NULL, (u64)-1);
3853 WARN_ON(fs_info->delalloc_block_rsv.size > 0);
3854 WARN_ON(fs_info->delalloc_block_rsv.reserved > 0);
3855 WARN_ON(fs_info->trans_block_rsv.size > 0);
3856 WARN_ON(fs_info->trans_block_rsv.reserved > 0);
3857 WARN_ON(fs_info->chunk_block_rsv.size > 0);
3858 WARN_ON(fs_info->chunk_block_rsv.reserved > 0);
3861 void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans,
3862 struct btrfs_root *root)
3864 if (!trans->bytes_reserved)
3867 BUG_ON(trans->block_rsv != &root->fs_info->trans_block_rsv);
3868 btrfs_block_rsv_release(root, trans->block_rsv,
3869 trans->bytes_reserved);
3870 trans->bytes_reserved = 0;
3873 int btrfs_orphan_reserve_metadata(struct btrfs_trans_handle *trans,
3874 struct inode *inode)
3876 struct btrfs_root *root = BTRFS_I(inode)->root;
3877 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
3878 struct btrfs_block_rsv *dst_rsv = root->orphan_block_rsv;
3881 * We need to hold space in order to delete our orphan item once we've
3882 * added it, so this takes the reservation so we can release it later
3883 * when we are truly done with the orphan item.
3885 u64 num_bytes = btrfs_calc_trans_metadata_size(root, 1);
3886 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3889 void btrfs_orphan_release_metadata(struct inode *inode)
3891 struct btrfs_root *root = BTRFS_I(inode)->root;
3892 u64 num_bytes = btrfs_calc_trans_metadata_size(root, 1);
3893 btrfs_block_rsv_release(root, root->orphan_block_rsv, num_bytes);
3896 int btrfs_snap_reserve_metadata(struct btrfs_trans_handle *trans,
3897 struct btrfs_pending_snapshot *pending)
3899 struct btrfs_root *root = pending->root;
3900 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
3901 struct btrfs_block_rsv *dst_rsv = &pending->block_rsv;
3903 * two for root back/forward refs, two for directory entries
3904 * and one for root of the snapshot.
3906 u64 num_bytes = btrfs_calc_trans_metadata_size(root, 5);
3907 dst_rsv->space_info = src_rsv->space_info;
3908 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3912 * drop_outstanding_extent - drop an outstanding extent
3913 * @inode: the inode we're dropping the extent for
3915 * This is called when we are freeing up an outstanding extent, either called
3916 * after an error or after an extent is written. This will return the number of
3917 * reserved extents that need to be freed. This must be called with
3918 * BTRFS_I(inode)->lock held.
3920 static unsigned drop_outstanding_extent(struct inode *inode)
3922 unsigned dropped_extents = 0;
3924 BUG_ON(!BTRFS_I(inode)->outstanding_extents);
3925 BTRFS_I(inode)->outstanding_extents--;
3928 * If we have more or the same amount of outsanding extents than we have
3929 * reserved then we need to leave the reserved extents count alone.
3931 if (BTRFS_I(inode)->outstanding_extents >=
3932 BTRFS_I(inode)->reserved_extents)
3935 dropped_extents = BTRFS_I(inode)->reserved_extents -
3936 BTRFS_I(inode)->outstanding_extents;
3937 BTRFS_I(inode)->reserved_extents -= dropped_extents;
3938 return dropped_extents;
3942 * calc_csum_metadata_size - return the amount of metada space that must be
3943 * reserved/free'd for the given bytes.
3944 * @inode: the inode we're manipulating
3945 * @num_bytes: the number of bytes in question
3946 * @reserve: 1 if we are reserving space, 0 if we are freeing space
3948 * This adjusts the number of csum_bytes in the inode and then returns the
3949 * correct amount of metadata that must either be reserved or freed. We
3950 * calculate how many checksums we can fit into one leaf and then divide the
3951 * number of bytes that will need to be checksumed by this value to figure out
3952 * how many checksums will be required. If we are adding bytes then the number
3953 * may go up and we will return the number of additional bytes that must be
3954 * reserved. If it is going down we will return the number of bytes that must
3957 * This must be called with BTRFS_I(inode)->lock held.
3959 static u64 calc_csum_metadata_size(struct inode *inode, u64 num_bytes,
3962 struct btrfs_root *root = BTRFS_I(inode)->root;
3964 int num_csums_per_leaf;
3968 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM &&
3969 BTRFS_I(inode)->csum_bytes == 0)
3972 old_csums = (int)div64_u64(BTRFS_I(inode)->csum_bytes, root->sectorsize);
3974 BTRFS_I(inode)->csum_bytes += num_bytes;
3976 BTRFS_I(inode)->csum_bytes -= num_bytes;
3977 csum_size = BTRFS_LEAF_DATA_SIZE(root) - sizeof(struct btrfs_item);
3978 num_csums_per_leaf = (int)div64_u64(csum_size,
3979 sizeof(struct btrfs_csum_item) +
3980 sizeof(struct btrfs_disk_key));
3981 num_csums = (int)div64_u64(BTRFS_I(inode)->csum_bytes, root->sectorsize);
3982 num_csums = num_csums + num_csums_per_leaf - 1;
3983 num_csums = num_csums / num_csums_per_leaf;
3985 old_csums = old_csums + num_csums_per_leaf - 1;
3986 old_csums = old_csums / num_csums_per_leaf;
3988 /* No change, no need to reserve more */
3989 if (old_csums == num_csums)
3993 return btrfs_calc_trans_metadata_size(root,
3994 num_csums - old_csums);
3996 return btrfs_calc_trans_metadata_size(root, old_csums - num_csums);
3999 int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
4001 struct btrfs_root *root = BTRFS_I(inode)->root;
4002 struct btrfs_block_rsv *block_rsv = &root->fs_info->delalloc_block_rsv;
4004 unsigned nr_extents = 0;
4007 if (btrfs_transaction_in_commit(root->fs_info))
4008 schedule_timeout(1);
4010 num_bytes = ALIGN(num_bytes, root->sectorsize);
4012 spin_lock(&BTRFS_I(inode)->lock);
4013 BTRFS_I(inode)->outstanding_extents++;
4015 if (BTRFS_I(inode)->outstanding_extents >
4016 BTRFS_I(inode)->reserved_extents) {
4017 nr_extents = BTRFS_I(inode)->outstanding_extents -
4018 BTRFS_I(inode)->reserved_extents;
4019 BTRFS_I(inode)->reserved_extents += nr_extents;
4021 to_reserve = btrfs_calc_trans_metadata_size(root, nr_extents);
4023 to_reserve += calc_csum_metadata_size(inode, num_bytes, 1);
4024 spin_unlock(&BTRFS_I(inode)->lock);
4026 ret = reserve_metadata_bytes(NULL, root, block_rsv, to_reserve, 1);
4030 * We don't need the return value since our reservation failed,
4031 * we just need to clean up our counter.
4033 spin_lock(&BTRFS_I(inode)->lock);
4034 dropped = drop_outstanding_extent(inode);
4035 WARN_ON(dropped > 1);
4036 BTRFS_I(inode)->csum_bytes -= num_bytes;
4037 spin_unlock(&BTRFS_I(inode)->lock);
4041 block_rsv_add_bytes(block_rsv, to_reserve, 1);
4047 * btrfs_delalloc_release_metadata - release a metadata reservation for an inode
4048 * @inode: the inode to release the reservation for
4049 * @num_bytes: the number of bytes we're releasing
4051 * This will release the metadata reservation for an inode. This can be called
4052 * once we complete IO for a given set of bytes to release their metadata
4055 void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes)
4057 struct btrfs_root *root = BTRFS_I(inode)->root;
4061 num_bytes = ALIGN(num_bytes, root->sectorsize);
4062 spin_lock(&BTRFS_I(inode)->lock);
4063 dropped = drop_outstanding_extent(inode);
4065 to_free = calc_csum_metadata_size(inode, num_bytes, 0);
4066 spin_unlock(&BTRFS_I(inode)->lock);
4068 to_free += btrfs_calc_trans_metadata_size(root, dropped);
4070 btrfs_block_rsv_release(root, &root->fs_info->delalloc_block_rsv,
4075 * btrfs_delalloc_reserve_space - reserve data and metadata space for delalloc
4076 * @inode: inode we're writing to
4077 * @num_bytes: the number of bytes we want to allocate
4079 * This will do the following things
4081 * o reserve space in the data space info for num_bytes
4082 * o reserve space in the metadata space info based on number of outstanding
4083 * extents and how much csums will be needed
4084 * o add to the inodes ->delalloc_bytes
4085 * o add it to the fs_info's delalloc inodes list.
4087 * This will return 0 for success and -ENOSPC if there is no space left.
4089 int btrfs_delalloc_reserve_space(struct inode *inode, u64 num_bytes)
4093 ret = btrfs_check_data_free_space(inode, num_bytes);
4097 ret = btrfs_delalloc_reserve_metadata(inode, num_bytes);
4099 btrfs_free_reserved_data_space(inode, num_bytes);
4107 * btrfs_delalloc_release_space - release data and metadata space for delalloc
4108 * @inode: inode we're releasing space for
4109 * @num_bytes: the number of bytes we want to free up
4111 * This must be matched with a call to btrfs_delalloc_reserve_space. This is
4112 * called in the case that we don't need the metadata AND data reservations
4113 * anymore. So if there is an error or we insert an inline extent.
4115 * This function will release the metadata space that was not used and will
4116 * decrement ->delalloc_bytes and remove it from the fs_info delalloc_inodes
4117 * list if there are no delalloc bytes left.
4119 void btrfs_delalloc_release_space(struct inode *inode, u64 num_bytes)
4121 btrfs_delalloc_release_metadata(inode, num_bytes);
4122 btrfs_free_reserved_data_space(inode, num_bytes);
4125 static int update_block_group(struct btrfs_trans_handle *trans,
4126 struct btrfs_root *root,
4127 u64 bytenr, u64 num_bytes, int alloc)
4129 struct btrfs_block_group_cache *cache = NULL;
4130 struct btrfs_fs_info *info = root->fs_info;
4131 u64 total = num_bytes;
4136 /* block accounting for super block */
4137 spin_lock(&info->delalloc_lock);
4138 old_val = btrfs_super_bytes_used(&info->super_copy);
4140 old_val += num_bytes;
4142 old_val -= num_bytes;
4143 btrfs_set_super_bytes_used(&info->super_copy, old_val);
4144 spin_unlock(&info->delalloc_lock);
4147 cache = btrfs_lookup_block_group(info, bytenr);
4150 if (cache->flags & (BTRFS_BLOCK_GROUP_DUP |
4151 BTRFS_BLOCK_GROUP_RAID1 |
4152 BTRFS_BLOCK_GROUP_RAID10))
4157 * If this block group has free space cache written out, we
4158 * need to make sure to load it if we are removing space. This
4159 * is because we need the unpinning stage to actually add the
4160 * space back to the block group, otherwise we will leak space.
4162 if (!alloc && cache->cached == BTRFS_CACHE_NO)
4163 cache_block_group(cache, trans, NULL, 1);
4165 byte_in_group = bytenr - cache->key.objectid;
4166 WARN_ON(byte_in_group > cache->key.offset);
4168 spin_lock(&cache->space_info->lock);
4169 spin_lock(&cache->lock);
4171 if (btrfs_super_cache_generation(&info->super_copy) != 0 &&
4172 cache->disk_cache_state < BTRFS_DC_CLEAR)
4173 cache->disk_cache_state = BTRFS_DC_CLEAR;
4176 old_val = btrfs_block_group_used(&cache->item);
4177 num_bytes = min(total, cache->key.offset - byte_in_group);
4179 old_val += num_bytes;
4180 btrfs_set_block_group_used(&cache->item, old_val);
4181 cache->reserved -= num_bytes;
4182 cache->space_info->bytes_reserved -= num_bytes;
4183 cache->space_info->bytes_used += num_bytes;
4184 cache->space_info->disk_used += num_bytes * factor;
4185 spin_unlock(&cache->lock);
4186 spin_unlock(&cache->space_info->lock);
4188 old_val -= num_bytes;
4189 btrfs_set_block_group_used(&cache->item, old_val);
4190 cache->pinned += num_bytes;
4191 cache->space_info->bytes_pinned += num_bytes;
4192 cache->space_info->bytes_used -= num_bytes;
4193 cache->space_info->disk_used -= num_bytes * factor;
4194 spin_unlock(&cache->lock);
4195 spin_unlock(&cache->space_info->lock);
4197 set_extent_dirty(info->pinned_extents,
4198 bytenr, bytenr + num_bytes - 1,
4199 GFP_NOFS | __GFP_NOFAIL);
4201 btrfs_put_block_group(cache);
4203 bytenr += num_bytes;
4208 static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
4210 struct btrfs_block_group_cache *cache;
4213 cache = btrfs_lookup_first_block_group(root->fs_info, search_start);
4217 bytenr = cache->key.objectid;
4218 btrfs_put_block_group(cache);
4223 static int pin_down_extent(struct btrfs_root *root,
4224 struct btrfs_block_group_cache *cache,
4225 u64 bytenr, u64 num_bytes, int reserved)
4227 spin_lock(&cache->space_info->lock);
4228 spin_lock(&cache->lock);
4229 cache->pinned += num_bytes;
4230 cache->space_info->bytes_pinned += num_bytes;
4232 cache->reserved -= num_bytes;
4233 cache->space_info->bytes_reserved -= num_bytes;
4235 spin_unlock(&cache->lock);
4236 spin_unlock(&cache->space_info->lock);
4238 set_extent_dirty(root->fs_info->pinned_extents, bytenr,
4239 bytenr + num_bytes - 1, GFP_NOFS | __GFP_NOFAIL);
4244 * this function must be called within transaction
4246 int btrfs_pin_extent(struct btrfs_root *root,
4247 u64 bytenr, u64 num_bytes, int reserved)
4249 struct btrfs_block_group_cache *cache;
4251 cache = btrfs_lookup_block_group(root->fs_info, bytenr);
4254 pin_down_extent(root, cache, bytenr, num_bytes, reserved);
4256 btrfs_put_block_group(cache);
4261 * btrfs_update_reserved_bytes - update the block_group and space info counters
4262 * @cache: The cache we are manipulating
4263 * @num_bytes: The number of bytes in question
4264 * @reserve: One of the reservation enums
4266 * This is called by the allocator when it reserves space, or by somebody who is
4267 * freeing space that was never actually used on disk. For example if you
4268 * reserve some space for a new leaf in transaction A and before transaction A
4269 * commits you free that leaf, you call this with reserve set to 0 in order to
4270 * clear the reservation.
4272 * Metadata reservations should be called with RESERVE_ALLOC so we do the proper
4273 * ENOSPC accounting. For data we handle the reservation through clearing the
4274 * delalloc bits in the io_tree. We have to do this since we could end up
4275 * allocating less disk space for the amount of data we have reserved in the
4276 * case of compression.
4278 * If this is a reservation and the block group has become read only we cannot
4279 * make the reservation and return -EAGAIN, otherwise this function always
4282 static int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache,
4283 u64 num_bytes, int reserve)
4285 struct btrfs_space_info *space_info = cache->space_info;
4287 spin_lock(&space_info->lock);
4288 spin_lock(&cache->lock);
4289 if (reserve != RESERVE_FREE) {
4293 cache->reserved += num_bytes;
4294 space_info->bytes_reserved += num_bytes;
4295 if (reserve == RESERVE_ALLOC) {
4296 BUG_ON(space_info->bytes_may_use < num_bytes);
4297 space_info->bytes_may_use -= num_bytes;
4302 space_info->bytes_readonly += num_bytes;
4303 cache->reserved -= num_bytes;
4304 space_info->bytes_reserved -= num_bytes;
4305 space_info->reservation_progress++;
4307 spin_unlock(&cache->lock);
4308 spin_unlock(&space_info->lock);
4312 int btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
4313 struct btrfs_root *root)
4315 struct btrfs_fs_info *fs_info = root->fs_info;
4316 struct btrfs_caching_control *next;
4317 struct btrfs_caching_control *caching_ctl;
4318 struct btrfs_block_group_cache *cache;
4320 down_write(&fs_info->extent_commit_sem);
4322 list_for_each_entry_safe(caching_ctl, next,
4323 &fs_info->caching_block_groups, list) {
4324 cache = caching_ctl->block_group;
4325 if (block_group_cache_done(cache)) {
4326 cache->last_byte_to_unpin = (u64)-1;
4327 list_del_init(&caching_ctl->list);
4328 put_caching_control(caching_ctl);
4330 cache->last_byte_to_unpin = caching_ctl->progress;
4334 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
4335 fs_info->pinned_extents = &fs_info->freed_extents[1];
4337 fs_info->pinned_extents = &fs_info->freed_extents[0];
4339 up_write(&fs_info->extent_commit_sem);
4341 update_global_block_rsv(fs_info);
4345 static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
4347 struct btrfs_fs_info *fs_info = root->fs_info;
4348 struct btrfs_block_group_cache *cache = NULL;
4351 while (start <= end) {
4353 start >= cache->key.objectid + cache->key.offset) {
4355 btrfs_put_block_group(cache);
4356 cache = btrfs_lookup_block_group(fs_info, start);
4360 len = cache->key.objectid + cache->key.offset - start;
4361 len = min(len, end + 1 - start);
4363 if (start < cache->last_byte_to_unpin) {
4364 len = min(len, cache->last_byte_to_unpin - start);
4365 btrfs_add_free_space(cache, start, len);
4370 spin_lock(&cache->space_info->lock);
4371 spin_lock(&cache->lock);
4372 cache->pinned -= len;
4373 cache->space_info->bytes_pinned -= len;
4375 cache->space_info->bytes_readonly += len;
4376 spin_unlock(&cache->lock);
4377 spin_unlock(&cache->space_info->lock);
4381 btrfs_put_block_group(cache);
4385 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
4386 struct btrfs_root *root)
4388 struct btrfs_fs_info *fs_info = root->fs_info;
4389 struct extent_io_tree *unpin;
4394 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
4395 unpin = &fs_info->freed_extents[1];
4397 unpin = &fs_info->freed_extents[0];
4400 ret = find_first_extent_bit(unpin, 0, &start, &end,
4405 if (btrfs_test_opt(root, DISCARD))
4406 ret = btrfs_discard_extent(root, start,
4407 end + 1 - start, NULL);
4409 clear_extent_dirty(unpin, start, end, GFP_NOFS);
4410 unpin_extent_range(root, start, end);
4417 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
4418 struct btrfs_root *root,
4419 u64 bytenr, u64 num_bytes, u64 parent,
4420 u64 root_objectid, u64 owner_objectid,
4421 u64 owner_offset, int refs_to_drop,
4422 struct btrfs_delayed_extent_op *extent_op)
4424 struct btrfs_key key;
4425 struct btrfs_path *path;
4426 struct btrfs_fs_info *info = root->fs_info;
4427 struct btrfs_root *extent_root = info->extent_root;
4428 struct extent_buffer *leaf;
4429 struct btrfs_extent_item *ei;
4430 struct btrfs_extent_inline_ref *iref;
4433 int extent_slot = 0;
4434 int found_extent = 0;
4439 path = btrfs_alloc_path();
4444 path->leave_spinning = 1;
4446 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
4447 BUG_ON(!is_data && refs_to_drop != 1);
4449 ret = lookup_extent_backref(trans, extent_root, path, &iref,
4450 bytenr, num_bytes, parent,
4451 root_objectid, owner_objectid,
4454 extent_slot = path->slots[0];
4455 while (extent_slot >= 0) {
4456 btrfs_item_key_to_cpu(path->nodes[0], &key,
4458 if (key.objectid != bytenr)
4460 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
4461 key.offset == num_bytes) {
4465 if (path->slots[0] - extent_slot > 5)
4469 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
4470 item_size = btrfs_item_size_nr(path->nodes[0], extent_slot);
4471 if (found_extent && item_size < sizeof(*ei))
4474 if (!found_extent) {
4476 ret = remove_extent_backref(trans, extent_root, path,
4480 btrfs_release_path(path);
4481 path->leave_spinning = 1;
4483 key.objectid = bytenr;
4484 key.type = BTRFS_EXTENT_ITEM_KEY;
4485 key.offset = num_bytes;
4487 ret = btrfs_search_slot(trans, extent_root,
4490 printk(KERN_ERR "umm, got %d back from search"
4491 ", was looking for %llu\n", ret,
4492 (unsigned long long)bytenr);
4494 btrfs_print_leaf(extent_root,
4498 extent_slot = path->slots[0];
4501 btrfs_print_leaf(extent_root, path->nodes[0]);
4503 printk(KERN_ERR "btrfs unable to find ref byte nr %llu "
4504 "parent %llu root %llu owner %llu offset %llu\n",
4505 (unsigned long long)bytenr,
4506 (unsigned long long)parent,
4507 (unsigned long long)root_objectid,
4508 (unsigned long long)owner_objectid,
4509 (unsigned long long)owner_offset);
4512 leaf = path->nodes[0];
4513 item_size = btrfs_item_size_nr(leaf, extent_slot);
4514 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
4515 if (item_size < sizeof(*ei)) {
4516 BUG_ON(found_extent || extent_slot != path->slots[0]);
4517 ret = convert_extent_item_v0(trans, extent_root, path,
4521 btrfs_release_path(path);
4522 path->leave_spinning = 1;
4524 key.objectid = bytenr;
4525 key.type = BTRFS_EXTENT_ITEM_KEY;
4526 key.offset = num_bytes;
4528 ret = btrfs_search_slot(trans, extent_root, &key, path,
4531 printk(KERN_ERR "umm, got %d back from search"
4532 ", was looking for %llu\n", ret,
4533 (unsigned long long)bytenr);
4534 btrfs_print_leaf(extent_root, path->nodes[0]);
4537 extent_slot = path->slots[0];
4538 leaf = path->nodes[0];
4539 item_size = btrfs_item_size_nr(leaf, extent_slot);
4542 BUG_ON(item_size < sizeof(*ei));
4543 ei = btrfs_item_ptr(leaf, extent_slot,
4544 struct btrfs_extent_item);
4545 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID) {
4546 struct btrfs_tree_block_info *bi;
4547 BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
4548 bi = (struct btrfs_tree_block_info *)(ei + 1);
4549 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
4552 refs = btrfs_extent_refs(leaf, ei);
4553 BUG_ON(refs < refs_to_drop);
4554 refs -= refs_to_drop;
4558 __run_delayed_extent_op(extent_op, leaf, ei);
4560 * In the case of inline back ref, reference count will
4561 * be updated by remove_extent_backref
4564 BUG_ON(!found_extent);
4566 btrfs_set_extent_refs(leaf, ei, refs);
4567 btrfs_mark_buffer_dirty(leaf);
4570 ret = remove_extent_backref(trans, extent_root, path,
4577 BUG_ON(is_data && refs_to_drop !=
4578 extent_data_ref_count(root, path, iref));
4580 BUG_ON(path->slots[0] != extent_slot);
4582 BUG_ON(path->slots[0] != extent_slot + 1);
4583 path->slots[0] = extent_slot;
4588 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
4591 btrfs_release_path(path);
4594 ret = btrfs_del_csums(trans, root, bytenr, num_bytes);
4597 invalidate_mapping_pages(info->btree_inode->i_mapping,
4598 bytenr >> PAGE_CACHE_SHIFT,
4599 (bytenr + num_bytes - 1) >> PAGE_CACHE_SHIFT);
4602 ret = update_block_group(trans, root, bytenr, num_bytes, 0);
4605 btrfs_free_path(path);
4610 * when we free an block, it is possible (and likely) that we free the last
4611 * delayed ref for that extent as well. This searches the delayed ref tree for
4612 * a given extent, and if there are no other delayed refs to be processed, it
4613 * removes it from the tree.
4615 static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans,
4616 struct btrfs_root *root, u64 bytenr)
4618 struct btrfs_delayed_ref_head *head;
4619 struct btrfs_delayed_ref_root *delayed_refs;
4620 struct btrfs_delayed_ref_node *ref;
4621 struct rb_node *node;
4624 delayed_refs = &trans->transaction->delayed_refs;
4625 spin_lock(&delayed_refs->lock);
4626 head = btrfs_find_delayed_ref_head(trans, bytenr);
4630 node = rb_prev(&head->node.rb_node);
4634 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
4636 /* there are still entries for this ref, we can't drop it */
4637 if (ref->bytenr == bytenr)
4640 if (head->extent_op) {
4641 if (!head->must_insert_reserved)
4643 kfree(head->extent_op);
4644 head->extent_op = NULL;
4648 * waiting for the lock here would deadlock. If someone else has it
4649 * locked they are already in the process of dropping it anyway
4651 if (!mutex_trylock(&head->mutex))
4655 * at this point we have a head with no other entries. Go
4656 * ahead and process it.
4658 head->node.in_tree = 0;
4659 rb_erase(&head->node.rb_node, &delayed_refs->root);
4661 delayed_refs->num_entries--;
4664 * we don't take a ref on the node because we're removing it from the
4665 * tree, so we just steal the ref the tree was holding.
4667 delayed_refs->num_heads--;
4668 if (list_empty(&head->cluster))
4669 delayed_refs->num_heads_ready--;
4671 list_del_init(&head->cluster);
4672 spin_unlock(&delayed_refs->lock);
4674 BUG_ON(head->extent_op);
4675 if (head->must_insert_reserved)
4678 mutex_unlock(&head->mutex);
4679 btrfs_put_delayed_ref(&head->node);
4682 spin_unlock(&delayed_refs->lock);
4686 void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
4687 struct btrfs_root *root,
4688 struct extent_buffer *buf,
4689 u64 parent, int last_ref)
4691 struct btrfs_block_rsv *block_rsv;
4692 struct btrfs_block_group_cache *cache = NULL;
4695 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4696 ret = btrfs_add_delayed_tree_ref(trans, buf->start, buf->len,
4697 parent, root->root_key.objectid,
4698 btrfs_header_level(buf),
4699 BTRFS_DROP_DELAYED_REF, NULL);
4706 block_rsv = get_block_rsv(trans, root);
4707 cache = btrfs_lookup_block_group(root->fs_info, buf->start);
4708 if (block_rsv->space_info != cache->space_info)
4711 if (btrfs_header_generation(buf) == trans->transid) {
4712 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4713 ret = check_ref_cleanup(trans, root, buf->start);
4718 if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
4719 pin_down_extent(root, cache, buf->start, buf->len, 1);
4723 WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags));
4725 btrfs_add_free_space(cache, buf->start, buf->len);
4726 btrfs_update_reserved_bytes(cache, buf->len, RESERVE_FREE);
4730 * Deleting the buffer, clear the corrupt flag since it doesn't matter
4733 clear_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags);
4734 btrfs_put_block_group(cache);
4737 int btrfs_free_extent(struct btrfs_trans_handle *trans,
4738 struct btrfs_root *root,
4739 u64 bytenr, u64 num_bytes, u64 parent,
4740 u64 root_objectid, u64 owner, u64 offset)
4745 * tree log blocks never actually go into the extent allocation
4746 * tree, just update pinning info and exit early.
4748 if (root_objectid == BTRFS_TREE_LOG_OBJECTID) {
4749 WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID);
4750 /* unlocks the pinned mutex */
4751 btrfs_pin_extent(root, bytenr, num_bytes, 1);
4753 } else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
4754 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
4755 parent, root_objectid, (int)owner,
4756 BTRFS_DROP_DELAYED_REF, NULL);
4759 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
4760 parent, root_objectid, owner,
4761 offset, BTRFS_DROP_DELAYED_REF, NULL);
4767 static u64 stripe_align(struct btrfs_root *root, u64 val)
4769 u64 mask = ((u64)root->stripesize - 1);
4770 u64 ret = (val + mask) & ~mask;
4775 * when we wait for progress in the block group caching, its because
4776 * our allocation attempt failed at least once. So, we must sleep
4777 * and let some progress happen before we try again.
4779 * This function will sleep at least once waiting for new free space to
4780 * show up, and then it will check the block group free space numbers
4781 * for our min num_bytes. Another option is to have it go ahead
4782 * and look in the rbtree for a free extent of a given size, but this
4786 wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
4789 struct btrfs_caching_control *caching_ctl;
4792 caching_ctl = get_caching_control(cache);
4796 wait_event(caching_ctl->wait, block_group_cache_done(cache) ||
4797 (cache->free_space_ctl->free_space >= num_bytes));
4799 put_caching_control(caching_ctl);
4804 wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
4806 struct btrfs_caching_control *caching_ctl;
4809 caching_ctl = get_caching_control(cache);
4813 wait_event(caching_ctl->wait, block_group_cache_done(cache));
4815 put_caching_control(caching_ctl);
4819 static int get_block_group_index(struct btrfs_block_group_cache *cache)
4822 if (cache->flags & BTRFS_BLOCK_GROUP_RAID10)
4824 else if (cache->flags & BTRFS_BLOCK_GROUP_RAID1)
4826 else if (cache->flags & BTRFS_BLOCK_GROUP_DUP)
4828 else if (cache->flags & BTRFS_BLOCK_GROUP_RAID0)
4835 enum btrfs_loop_type {
4836 LOOP_FIND_IDEAL = 0,
4837 LOOP_CACHING_NOWAIT = 1,
4838 LOOP_CACHING_WAIT = 2,
4839 LOOP_ALLOC_CHUNK = 3,
4840 LOOP_NO_EMPTY_SIZE = 4,
4844 * walks the btree of allocated extents and find a hole of a given size.
4845 * The key ins is changed to record the hole:
4846 * ins->objectid == block start
4847 * ins->flags = BTRFS_EXTENT_ITEM_KEY
4848 * ins->offset == number of blocks
4849 * Any available blocks before search_start are skipped.
4851 static noinline int find_free_extent(struct btrfs_trans_handle *trans,
4852 struct btrfs_root *orig_root,
4853 u64 num_bytes, u64 empty_size,
4854 u64 search_start, u64 search_end,
4855 u64 hint_byte, struct btrfs_key *ins,
4859 struct btrfs_root *root = orig_root->fs_info->extent_root;
4860 struct btrfs_free_cluster *last_ptr = NULL;
4861 struct btrfs_block_group_cache *block_group = NULL;
4862 int empty_cluster = 2 * 1024 * 1024;
4863 int allowed_chunk_alloc = 0;
4864 int done_chunk_alloc = 0;
4865 struct btrfs_space_info *space_info;
4866 int last_ptr_loop = 0;
4869 int alloc_type = (data & BTRFS_BLOCK_GROUP_DATA) ?
4870 RESERVE_ALLOC_NO_ACCOUNT : RESERVE_ALLOC;
4871 bool found_uncached_bg = false;
4872 bool failed_cluster_refill = false;
4873 bool failed_alloc = false;
4874 bool use_cluster = true;
4875 u64 ideal_cache_percent = 0;
4876 u64 ideal_cache_offset = 0;
4878 WARN_ON(num_bytes < root->sectorsize);
4879 btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
4883 space_info = __find_space_info(root->fs_info, data);
4885 printk(KERN_ERR "No space info for %llu\n", data);
4890 * If the space info is for both data and metadata it means we have a
4891 * small filesystem and we can't use the clustering stuff.
4893 if (btrfs_mixed_space_info(space_info))
4894 use_cluster = false;
4896 if (orig_root->ref_cows || empty_size)
4897 allowed_chunk_alloc = 1;
4899 if (data & BTRFS_BLOCK_GROUP_METADATA && use_cluster) {
4900 last_ptr = &root->fs_info->meta_alloc_cluster;
4901 if (!btrfs_test_opt(root, SSD))
4902 empty_cluster = 64 * 1024;
4905 if ((data & BTRFS_BLOCK_GROUP_DATA) && use_cluster &&
4906 btrfs_test_opt(root, SSD)) {
4907 last_ptr = &root->fs_info->data_alloc_cluster;
4911 spin_lock(&last_ptr->lock);
4912 if (last_ptr->block_group)
4913 hint_byte = last_ptr->window_start;
4914 spin_unlock(&last_ptr->lock);
4917 search_start = max(search_start, first_logical_byte(root, 0));
4918 search_start = max(search_start, hint_byte);
4923 if (search_start == hint_byte) {
4925 block_group = btrfs_lookup_block_group(root->fs_info,
4928 * we don't want to use the block group if it doesn't match our
4929 * allocation bits, or if its not cached.
4931 * However if we are re-searching with an ideal block group
4932 * picked out then we don't care that the block group is cached.
4934 if (block_group && block_group_bits(block_group, data) &&
4935 (block_group->cached != BTRFS_CACHE_NO ||
4936 search_start == ideal_cache_offset)) {
4937 down_read(&space_info->groups_sem);
4938 if (list_empty(&block_group->list) ||
4941 * someone is removing this block group,
4942 * we can't jump into the have_block_group
4943 * target because our list pointers are not
4946 btrfs_put_block_group(block_group);
4947 up_read(&space_info->groups_sem);
4949 index = get_block_group_index(block_group);
4950 goto have_block_group;
4952 } else if (block_group) {
4953 btrfs_put_block_group(block_group);
4957 down_read(&space_info->groups_sem);
4958 list_for_each_entry(block_group, &space_info->block_groups[index],
4963 btrfs_get_block_group(block_group);
4964 search_start = block_group->key.objectid;
4967 * this can happen if we end up cycling through all the
4968 * raid types, but we want to make sure we only allocate
4969 * for the proper type.
4971 if (!block_group_bits(block_group, data)) {
4972 u64 extra = BTRFS_BLOCK_GROUP_DUP |
4973 BTRFS_BLOCK_GROUP_RAID1 |
4974 BTRFS_BLOCK_GROUP_RAID10;
4977 * if they asked for extra copies and this block group
4978 * doesn't provide them, bail. This does allow us to
4979 * fill raid0 from raid1.
4981 if ((data & extra) && !(block_group->flags & extra))
4986 if (unlikely(block_group->cached == BTRFS_CACHE_NO)) {
4989 ret = cache_block_group(block_group, trans,
4991 if (block_group->cached == BTRFS_CACHE_FINISHED)
4992 goto have_block_group;
4994 free_percent = btrfs_block_group_used(&block_group->item);
4995 free_percent *= 100;
4996 free_percent = div64_u64(free_percent,
4997 block_group->key.offset);
4998 free_percent = 100 - free_percent;
4999 if (free_percent > ideal_cache_percent &&
5000 likely(!block_group->ro)) {
5001 ideal_cache_offset = block_group->key.objectid;
5002 ideal_cache_percent = free_percent;
5006 * The caching workers are limited to 2 threads, so we
5007 * can queue as much work as we care to.
5009 if (loop > LOOP_FIND_IDEAL) {
5010 ret = cache_block_group(block_group, trans,
5014 found_uncached_bg = true;
5017 * If loop is set for cached only, try the next block
5020 if (loop == LOOP_FIND_IDEAL)
5024 cached = block_group_cache_done(block_group);
5025 if (unlikely(!cached))
5026 found_uncached_bg = true;
5028 if (unlikely(block_group->ro))
5031 spin_lock(&block_group->free_space_ctl->tree_lock);
5033 block_group->free_space_ctl->free_space <
5034 num_bytes + empty_size) {
5035 spin_unlock(&block_group->free_space_ctl->tree_lock);
5038 spin_unlock(&block_group->free_space_ctl->tree_lock);
5041 * Ok we want to try and use the cluster allocator, so lets look
5042 * there, unless we are on LOOP_NO_EMPTY_SIZE, since we will
5043 * have tried the cluster allocator plenty of times at this
5044 * point and not have found anything, so we are likely way too
5045 * fragmented for the clustering stuff to find anything, so lets
5046 * just skip it and let the allocator find whatever block it can
5049 if (last_ptr && loop < LOOP_NO_EMPTY_SIZE) {
5051 * the refill lock keeps out other
5052 * people trying to start a new cluster
5054 spin_lock(&last_ptr->refill_lock);
5055 if (last_ptr->block_group &&
5056 (last_ptr->block_group->ro ||
5057 !block_group_bits(last_ptr->block_group, data))) {
5059 goto refill_cluster;
5062 offset = btrfs_alloc_from_cluster(block_group, last_ptr,
5063 num_bytes, search_start);
5065 /* we have a block, we're done */
5066 spin_unlock(&last_ptr->refill_lock);
5070 spin_lock(&last_ptr->lock);
5072 * whoops, this cluster doesn't actually point to
5073 * this block group. Get a ref on the block
5074 * group is does point to and try again
5076 if (!last_ptr_loop && last_ptr->block_group &&
5077 last_ptr->block_group != block_group &&
5079 get_block_group_index(last_ptr->block_group)) {
5081 btrfs_put_block_group(block_group);
5082 block_group = last_ptr->block_group;
5083 btrfs_get_block_group(block_group);
5084 spin_unlock(&last_ptr->lock);
5085 spin_unlock(&last_ptr->refill_lock);
5088 search_start = block_group->key.objectid;
5090 * we know this block group is properly
5091 * in the list because
5092 * btrfs_remove_block_group, drops the
5093 * cluster before it removes the block
5094 * group from the list
5096 goto have_block_group;
5098 spin_unlock(&last_ptr->lock);
5101 * this cluster didn't work out, free it and
5104 btrfs_return_cluster_to_free_space(NULL, last_ptr);
5108 /* allocate a cluster in this block group */
5109 ret = btrfs_find_space_cluster(trans, root,
5110 block_group, last_ptr,
5112 empty_cluster + empty_size);
5115 * now pull our allocation out of this
5118 offset = btrfs_alloc_from_cluster(block_group,
5119 last_ptr, num_bytes,
5122 /* we found one, proceed */
5123 spin_unlock(&last_ptr->refill_lock);
5126 } else if (!cached && loop > LOOP_CACHING_NOWAIT
5127 && !failed_cluster_refill) {
5128 spin_unlock(&last_ptr->refill_lock);
5130 failed_cluster_refill = true;
5131 wait_block_group_cache_progress(block_group,
5132 num_bytes + empty_cluster + empty_size);
5133 goto have_block_group;
5137 * at this point we either didn't find a cluster
5138 * or we weren't able to allocate a block from our
5139 * cluster. Free the cluster we've been trying
5140 * to use, and go to the next block group
5142 btrfs_return_cluster_to_free_space(NULL, last_ptr);
5143 spin_unlock(&last_ptr->refill_lock);
5147 offset = btrfs_find_space_for_alloc(block_group, search_start,
5148 num_bytes, empty_size);
5150 * If we didn't find a chunk, and we haven't failed on this
5151 * block group before, and this block group is in the middle of
5152 * caching and we are ok with waiting, then go ahead and wait
5153 * for progress to be made, and set failed_alloc to true.
5155 * If failed_alloc is true then we've already waited on this
5156 * block group once and should move on to the next block group.
5158 if (!offset && !failed_alloc && !cached &&
5159 loop > LOOP_CACHING_NOWAIT) {
5160 wait_block_group_cache_progress(block_group,
5161 num_bytes + empty_size);
5162 failed_alloc = true;
5163 goto have_block_group;
5164 } else if (!offset) {
5168 search_start = stripe_align(root, offset);
5169 /* move on to the next group */
5170 if (search_start + num_bytes >= search_end) {
5171 btrfs_add_free_space(block_group, offset, num_bytes);
5175 /* move on to the next group */
5176 if (search_start + num_bytes >
5177 block_group->key.objectid + block_group->key.offset) {
5178 btrfs_add_free_space(block_group, offset, num_bytes);
5182 ins->objectid = search_start;
5183 ins->offset = num_bytes;
5185 if (offset < search_start)
5186 btrfs_add_free_space(block_group, offset,
5187 search_start - offset);
5188 BUG_ON(offset > search_start);
5190 ret = btrfs_update_reserved_bytes(block_group, num_bytes,
5192 if (ret == -EAGAIN) {
5193 btrfs_add_free_space(block_group, offset, num_bytes);
5197 /* we are all good, lets return */
5198 ins->objectid = search_start;
5199 ins->offset = num_bytes;
5201 if (offset < search_start)
5202 btrfs_add_free_space(block_group, offset,
5203 search_start - offset);
5204 BUG_ON(offset > search_start);
5205 btrfs_put_block_group(block_group);
5208 failed_cluster_refill = false;
5209 failed_alloc = false;
5210 BUG_ON(index != get_block_group_index(block_group));
5211 btrfs_put_block_group(block_group);
5213 up_read(&space_info->groups_sem);
5215 if (!ins->objectid && ++index < BTRFS_NR_RAID_TYPES)
5218 /* LOOP_FIND_IDEAL, only search caching/cached bg's, and don't wait for
5219 * for them to make caching progress. Also
5220 * determine the best possible bg to cache
5221 * LOOP_CACHING_NOWAIT, search partially cached block groups, kicking
5222 * caching kthreads as we move along
5223 * LOOP_CACHING_WAIT, search everything, and wait if our bg is caching
5224 * LOOP_ALLOC_CHUNK, force a chunk allocation and try again
5225 * LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try
5228 if (!ins->objectid && loop < LOOP_NO_EMPTY_SIZE) {
5230 if (loop == LOOP_FIND_IDEAL && found_uncached_bg) {
5231 found_uncached_bg = false;
5233 if (!ideal_cache_percent)
5237 * 1 of the following 2 things have happened so far
5239 * 1) We found an ideal block group for caching that
5240 * is mostly full and will cache quickly, so we might
5241 * as well wait for it.
5243 * 2) We searched for cached only and we didn't find
5244 * anything, and we didn't start any caching kthreads
5245 * either, so chances are we will loop through and
5246 * start a couple caching kthreads, and then come back
5247 * around and just wait for them. This will be slower
5248 * because we will have 2 caching kthreads reading at
5249 * the same time when we could have just started one
5250 * and waited for it to get far enough to give us an
5251 * allocation, so go ahead and go to the wait caching
5254 loop = LOOP_CACHING_WAIT;
5255 search_start = ideal_cache_offset;
5256 ideal_cache_percent = 0;
5258 } else if (loop == LOOP_FIND_IDEAL) {
5260 * Didn't find a uncached bg, wait on anything we find
5263 loop = LOOP_CACHING_WAIT;
5269 if (loop == LOOP_ALLOC_CHUNK) {
5270 if (allowed_chunk_alloc) {
5271 ret = do_chunk_alloc(trans, root, num_bytes +
5272 2 * 1024 * 1024, data,
5273 CHUNK_ALLOC_LIMITED);
5274 allowed_chunk_alloc = 0;
5276 done_chunk_alloc = 1;
5277 } else if (!done_chunk_alloc &&
5278 space_info->force_alloc ==
5279 CHUNK_ALLOC_NO_FORCE) {
5280 space_info->force_alloc = CHUNK_ALLOC_LIMITED;
5284 * We didn't allocate a chunk, go ahead and drop the
5285 * empty size and loop again.
5287 if (!done_chunk_alloc)
5288 loop = LOOP_NO_EMPTY_SIZE;
5291 if (loop == LOOP_NO_EMPTY_SIZE) {
5297 } else if (!ins->objectid) {
5299 } else if (ins->objectid) {
5306 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
5307 int dump_block_groups)
5309 struct btrfs_block_group_cache *cache;
5312 spin_lock(&info->lock);
5313 printk(KERN_INFO "space_info %llu has %llu free, is %sfull\n",
5314 (unsigned long long)info->flags,
5315 (unsigned long long)(info->total_bytes - info->bytes_used -
5316 info->bytes_pinned - info->bytes_reserved -
5317 info->bytes_readonly),
5318 (info->full) ? "" : "not ");
5319 printk(KERN_INFO "space_info total=%llu, used=%llu, pinned=%llu, "
5320 "reserved=%llu, may_use=%llu, readonly=%llu\n",
5321 (unsigned long long)info->total_bytes,
5322 (unsigned long long)info->bytes_used,
5323 (unsigned long long)info->bytes_pinned,
5324 (unsigned long long)info->bytes_reserved,
5325 (unsigned long long)info->bytes_may_use,
5326 (unsigned long long)info->bytes_readonly);
5327 spin_unlock(&info->lock);
5329 if (!dump_block_groups)
5332 down_read(&info->groups_sem);
5334 list_for_each_entry(cache, &info->block_groups[index], list) {
5335 spin_lock(&cache->lock);
5336 printk(KERN_INFO "block group %llu has %llu bytes, %llu used "
5337 "%llu pinned %llu reserved\n",
5338 (unsigned long long)cache->key.objectid,
5339 (unsigned long long)cache->key.offset,
5340 (unsigned long long)btrfs_block_group_used(&cache->item),
5341 (unsigned long long)cache->pinned,
5342 (unsigned long long)cache->reserved);
5343 btrfs_dump_free_space(cache, bytes);
5344 spin_unlock(&cache->lock);
5346 if (++index < BTRFS_NR_RAID_TYPES)
5348 up_read(&info->groups_sem);
5351 int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
5352 struct btrfs_root *root,
5353 u64 num_bytes, u64 min_alloc_size,
5354 u64 empty_size, u64 hint_byte,
5355 u64 search_end, struct btrfs_key *ins,
5359 u64 search_start = 0;
5361 data = btrfs_get_alloc_profile(root, data);
5364 * the only place that sets empty_size is btrfs_realloc_node, which
5365 * is not called recursively on allocations
5367 if (empty_size || root->ref_cows)
5368 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
5369 num_bytes + 2 * 1024 * 1024, data,
5370 CHUNK_ALLOC_NO_FORCE);
5372 WARN_ON(num_bytes < root->sectorsize);
5373 ret = find_free_extent(trans, root, num_bytes, empty_size,
5374 search_start, search_end, hint_byte,
5377 if (ret == -ENOSPC && num_bytes > min_alloc_size) {
5378 num_bytes = num_bytes >> 1;
5379 num_bytes = num_bytes & ~(root->sectorsize - 1);
5380 num_bytes = max(num_bytes, min_alloc_size);
5381 do_chunk_alloc(trans, root->fs_info->extent_root,
5382 num_bytes, data, CHUNK_ALLOC_FORCE);
5385 if (ret == -ENOSPC && btrfs_test_opt(root, ENOSPC_DEBUG)) {
5386 struct btrfs_space_info *sinfo;
5388 sinfo = __find_space_info(root->fs_info, data);
5389 printk(KERN_ERR "btrfs allocation failed flags %llu, "
5390 "wanted %llu\n", (unsigned long long)data,
5391 (unsigned long long)num_bytes);
5392 dump_space_info(sinfo, num_bytes, 1);
5395 trace_btrfs_reserved_extent_alloc(root, ins->objectid, ins->offset);
5400 int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len)
5402 struct btrfs_block_group_cache *cache;
5405 cache = btrfs_lookup_block_group(root->fs_info, start);
5407 printk(KERN_ERR "Unable to find block group for %llu\n",
5408 (unsigned long long)start);
5412 if (btrfs_test_opt(root, DISCARD))
5413 ret = btrfs_discard_extent(root, start, len, NULL);
5415 btrfs_add_free_space(cache, start, len);
5416 btrfs_update_reserved_bytes(cache, len, RESERVE_FREE);
5417 btrfs_put_block_group(cache);
5419 trace_btrfs_reserved_extent_free(root, start, len);
5424 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
5425 struct btrfs_root *root,
5426 u64 parent, u64 root_objectid,
5427 u64 flags, u64 owner, u64 offset,
5428 struct btrfs_key *ins, int ref_mod)
5431 struct btrfs_fs_info *fs_info = root->fs_info;
5432 struct btrfs_extent_item *extent_item;
5433 struct btrfs_extent_inline_ref *iref;
5434 struct btrfs_path *path;
5435 struct extent_buffer *leaf;
5440 type = BTRFS_SHARED_DATA_REF_KEY;
5442 type = BTRFS_EXTENT_DATA_REF_KEY;
5444 size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type);
5446 path = btrfs_alloc_path();
5450 path->leave_spinning = 1;
5451 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
5455 leaf = path->nodes[0];
5456 extent_item = btrfs_item_ptr(leaf, path->slots[0],
5457 struct btrfs_extent_item);
5458 btrfs_set_extent_refs(leaf, extent_item, ref_mod);
5459 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
5460 btrfs_set_extent_flags(leaf, extent_item,
5461 flags | BTRFS_EXTENT_FLAG_DATA);
5463 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
5464 btrfs_set_extent_inline_ref_type(leaf, iref, type);
5466 struct btrfs_shared_data_ref *ref;
5467 ref = (struct btrfs_shared_data_ref *)(iref + 1);
5468 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
5469 btrfs_set_shared_data_ref_count(leaf, ref, ref_mod);
5471 struct btrfs_extent_data_ref *ref;
5472 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
5473 btrfs_set_extent_data_ref_root(leaf, ref, root_objectid);
5474 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
5475 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
5476 btrfs_set_extent_data_ref_count(leaf, ref, ref_mod);
5479 btrfs_mark_buffer_dirty(path->nodes[0]);
5480 btrfs_free_path(path);
5482 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
5484 printk(KERN_ERR "btrfs update block group failed for %llu "
5485 "%llu\n", (unsigned long long)ins->objectid,
5486 (unsigned long long)ins->offset);
5492 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
5493 struct btrfs_root *root,
5494 u64 parent, u64 root_objectid,
5495 u64 flags, struct btrfs_disk_key *key,
5496 int level, struct btrfs_key *ins)
5499 struct btrfs_fs_info *fs_info = root->fs_info;
5500 struct btrfs_extent_item *extent_item;
5501 struct btrfs_tree_block_info *block_info;
5502 struct btrfs_extent_inline_ref *iref;
5503 struct btrfs_path *path;
5504 struct extent_buffer *leaf;
5505 u32 size = sizeof(*extent_item) + sizeof(*block_info) + sizeof(*iref);
5507 path = btrfs_alloc_path();
5511 path->leave_spinning = 1;
5512 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
5516 leaf = path->nodes[0];
5517 extent_item = btrfs_item_ptr(leaf, path->slots[0],
5518 struct btrfs_extent_item);
5519 btrfs_set_extent_refs(leaf, extent_item, 1);
5520 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
5521 btrfs_set_extent_flags(leaf, extent_item,
5522 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
5523 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
5525 btrfs_set_tree_block_key(leaf, block_info, key);
5526 btrfs_set_tree_block_level(leaf, block_info, level);
5528 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
5530 BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF));
5531 btrfs_set_extent_inline_ref_type(leaf, iref,
5532 BTRFS_SHARED_BLOCK_REF_KEY);
5533 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
5535 btrfs_set_extent_inline_ref_type(leaf, iref,
5536 BTRFS_TREE_BLOCK_REF_KEY);
5537 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
5540 btrfs_mark_buffer_dirty(leaf);
5541 btrfs_free_path(path);
5543 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
5545 printk(KERN_ERR "btrfs update block group failed for %llu "
5546 "%llu\n", (unsigned long long)ins->objectid,
5547 (unsigned long long)ins->offset);
5553 int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
5554 struct btrfs_root *root,
5555 u64 root_objectid, u64 owner,
5556 u64 offset, struct btrfs_key *ins)
5560 BUG_ON(root_objectid == BTRFS_TREE_LOG_OBJECTID);
5562 ret = btrfs_add_delayed_data_ref(trans, ins->objectid, ins->offset,
5563 0, root_objectid, owner, offset,
5564 BTRFS_ADD_DELAYED_EXTENT, NULL);
5569 * this is used by the tree logging recovery code. It records that
5570 * an extent has been allocated and makes sure to clear the free
5571 * space cache bits as well
5573 int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
5574 struct btrfs_root *root,
5575 u64 root_objectid, u64 owner, u64 offset,
5576 struct btrfs_key *ins)
5579 struct btrfs_block_group_cache *block_group;
5580 struct btrfs_caching_control *caching_ctl;
5581 u64 start = ins->objectid;
5582 u64 num_bytes = ins->offset;
5584 block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
5585 cache_block_group(block_group, trans, NULL, 0);
5586 caching_ctl = get_caching_control(block_group);
5589 BUG_ON(!block_group_cache_done(block_group));
5590 ret = btrfs_remove_free_space(block_group, start, num_bytes);
5593 mutex_lock(&caching_ctl->mutex);
5595 if (start >= caching_ctl->progress) {
5596 ret = add_excluded_extent(root, start, num_bytes);
5598 } else if (start + num_bytes <= caching_ctl->progress) {
5599 ret = btrfs_remove_free_space(block_group,
5603 num_bytes = caching_ctl->progress - start;
5604 ret = btrfs_remove_free_space(block_group,
5608 start = caching_ctl->progress;
5609 num_bytes = ins->objectid + ins->offset -
5610 caching_ctl->progress;
5611 ret = add_excluded_extent(root, start, num_bytes);
5615 mutex_unlock(&caching_ctl->mutex);
5616 put_caching_control(caching_ctl);
5619 ret = btrfs_update_reserved_bytes(block_group, ins->offset,
5620 RESERVE_ALLOC_NO_ACCOUNT);
5622 btrfs_put_block_group(block_group);
5623 ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,
5624 0, owner, offset, ins, 1);
5628 struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
5629 struct btrfs_root *root,
5630 u64 bytenr, u32 blocksize,
5633 struct extent_buffer *buf;
5635 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
5637 return ERR_PTR(-ENOMEM);
5638 btrfs_set_header_generation(buf, trans->transid);
5639 btrfs_set_buffer_lockdep_class(root->root_key.objectid, buf, level);
5640 btrfs_tree_lock(buf);
5641 clean_tree_block(trans, root, buf);
5643 btrfs_set_lock_blocking(buf);
5644 btrfs_set_buffer_uptodate(buf);
5646 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
5648 * we allow two log transactions at a time, use different
5649 * EXENT bit to differentiate dirty pages.
5651 if (root->log_transid % 2 == 0)
5652 set_extent_dirty(&root->dirty_log_pages, buf->start,
5653 buf->start + buf->len - 1, GFP_NOFS);
5655 set_extent_new(&root->dirty_log_pages, buf->start,
5656 buf->start + buf->len - 1, GFP_NOFS);
5658 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
5659 buf->start + buf->len - 1, GFP_NOFS);
5661 trans->blocks_used++;
5662 /* this returns a buffer locked for blocking */
5666 static struct btrfs_block_rsv *
5667 use_block_rsv(struct btrfs_trans_handle *trans,
5668 struct btrfs_root *root, u32 blocksize)
5670 struct btrfs_block_rsv *block_rsv;
5671 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
5674 block_rsv = get_block_rsv(trans, root);
5676 if (block_rsv->size == 0) {
5677 ret = reserve_metadata_bytes(trans, root, block_rsv,
5680 * If we couldn't reserve metadata bytes try and use some from
5681 * the global reserve.
5683 if (ret && block_rsv != global_rsv) {
5684 ret = block_rsv_use_bytes(global_rsv, blocksize);
5687 return ERR_PTR(ret);
5689 return ERR_PTR(ret);
5694 ret = block_rsv_use_bytes(block_rsv, blocksize);
5699 ret = reserve_metadata_bytes(trans, root, block_rsv, blocksize,
5702 spin_lock(&block_rsv->lock);
5703 block_rsv->size += blocksize;
5704 spin_unlock(&block_rsv->lock);
5706 } else if (ret && block_rsv != global_rsv) {
5707 ret = block_rsv_use_bytes(global_rsv, blocksize);
5713 return ERR_PTR(-ENOSPC);
5716 static void unuse_block_rsv(struct btrfs_block_rsv *block_rsv, u32 blocksize)
5718 block_rsv_add_bytes(block_rsv, blocksize, 0);
5719 block_rsv_release_bytes(block_rsv, NULL, 0);
5723 * finds a free extent and does all the dirty work required for allocation
5724 * returns the key for the extent through ins, and a tree buffer for
5725 * the first block of the extent through buf.
5727 * returns the tree buffer or NULL.
5729 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
5730 struct btrfs_root *root, u32 blocksize,
5731 u64 parent, u64 root_objectid,
5732 struct btrfs_disk_key *key, int level,
5733 u64 hint, u64 empty_size)
5735 struct btrfs_key ins;
5736 struct btrfs_block_rsv *block_rsv;
5737 struct extent_buffer *buf;
5742 block_rsv = use_block_rsv(trans, root, blocksize);
5743 if (IS_ERR(block_rsv))
5744 return ERR_CAST(block_rsv);
5746 ret = btrfs_reserve_extent(trans, root, blocksize, blocksize,
5747 empty_size, hint, (u64)-1, &ins, 0);
5749 unuse_block_rsv(block_rsv, blocksize);
5750 return ERR_PTR(ret);
5753 buf = btrfs_init_new_buffer(trans, root, ins.objectid,
5755 BUG_ON(IS_ERR(buf));
5757 if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
5759 parent = ins.objectid;
5760 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
5764 if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
5765 struct btrfs_delayed_extent_op *extent_op;
5766 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
5769 memcpy(&extent_op->key, key, sizeof(extent_op->key));
5771 memset(&extent_op->key, 0, sizeof(extent_op->key));
5772 extent_op->flags_to_set = flags;
5773 extent_op->update_key = 1;
5774 extent_op->update_flags = 1;
5775 extent_op->is_data = 0;
5777 ret = btrfs_add_delayed_tree_ref(trans, ins.objectid,
5778 ins.offset, parent, root_objectid,
5779 level, BTRFS_ADD_DELAYED_EXTENT,
5786 struct walk_control {
5787 u64 refs[BTRFS_MAX_LEVEL];
5788 u64 flags[BTRFS_MAX_LEVEL];
5789 struct btrfs_key update_progress;
5799 #define DROP_REFERENCE 1
5800 #define UPDATE_BACKREF 2
5802 static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
5803 struct btrfs_root *root,
5804 struct walk_control *wc,
5805 struct btrfs_path *path)
5813 struct btrfs_key key;
5814 struct extent_buffer *eb;
5819 if (path->slots[wc->level] < wc->reada_slot) {
5820 wc->reada_count = wc->reada_count * 2 / 3;
5821 wc->reada_count = max(wc->reada_count, 2);
5823 wc->reada_count = wc->reada_count * 3 / 2;
5824 wc->reada_count = min_t(int, wc->reada_count,
5825 BTRFS_NODEPTRS_PER_BLOCK(root));
5828 eb = path->nodes[wc->level];
5829 nritems = btrfs_header_nritems(eb);
5830 blocksize = btrfs_level_size(root, wc->level - 1);
5832 for (slot = path->slots[wc->level]; slot < nritems; slot++) {
5833 if (nread >= wc->reada_count)
5837 bytenr = btrfs_node_blockptr(eb, slot);
5838 generation = btrfs_node_ptr_generation(eb, slot);
5840 if (slot == path->slots[wc->level])
5843 if (wc->stage == UPDATE_BACKREF &&
5844 generation <= root->root_key.offset)
5847 /* We don't lock the tree block, it's OK to be racy here */
5848 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
5853 if (wc->stage == DROP_REFERENCE) {
5857 if (wc->level == 1 &&
5858 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5860 if (!wc->update_ref ||
5861 generation <= root->root_key.offset)
5863 btrfs_node_key_to_cpu(eb, &key, slot);
5864 ret = btrfs_comp_cpu_keys(&key,
5865 &wc->update_progress);
5869 if (wc->level == 1 &&
5870 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5874 ret = readahead_tree_block(root, bytenr, blocksize,
5880 wc->reada_slot = slot;
5884 * hepler to process tree block while walking down the tree.
5886 * when wc->stage == UPDATE_BACKREF, this function updates
5887 * back refs for pointers in the block.
5889 * NOTE: return value 1 means we should stop walking down.
5891 static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
5892 struct btrfs_root *root,
5893 struct btrfs_path *path,
5894 struct walk_control *wc, int lookup_info)
5896 int level = wc->level;
5897 struct extent_buffer *eb = path->nodes[level];
5898 u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF;
5901 if (wc->stage == UPDATE_BACKREF &&
5902 btrfs_header_owner(eb) != root->root_key.objectid)
5906 * when reference count of tree block is 1, it won't increase
5907 * again. once full backref flag is set, we never clear it.
5910 ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
5911 (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag)))) {
5912 BUG_ON(!path->locks[level]);
5913 ret = btrfs_lookup_extent_info(trans, root,
5918 BUG_ON(wc->refs[level] == 0);
5921 if (wc->stage == DROP_REFERENCE) {
5922 if (wc->refs[level] > 1)
5925 if (path->locks[level] && !wc->keep_locks) {
5926 btrfs_tree_unlock_rw(eb, path->locks[level]);
5927 path->locks[level] = 0;
5932 /* wc->stage == UPDATE_BACKREF */
5933 if (!(wc->flags[level] & flag)) {
5934 BUG_ON(!path->locks[level]);
5935 ret = btrfs_inc_ref(trans, root, eb, 1);
5937 ret = btrfs_dec_ref(trans, root, eb, 0);
5939 ret = btrfs_set_disk_extent_flags(trans, root, eb->start,
5942 wc->flags[level] |= flag;
5946 * the block is shared by multiple trees, so it's not good to
5947 * keep the tree lock
5949 if (path->locks[level] && level > 0) {
5950 btrfs_tree_unlock_rw(eb, path->locks[level]);
5951 path->locks[level] = 0;
5957 * hepler to process tree block pointer.
5959 * when wc->stage == DROP_REFERENCE, this function checks
5960 * reference count of the block pointed to. if the block
5961 * is shared and we need update back refs for the subtree
5962 * rooted at the block, this function changes wc->stage to
5963 * UPDATE_BACKREF. if the block is shared and there is no
5964 * need to update back, this function drops the reference
5967 * NOTE: return value 1 means we should stop walking down.
5969 static noinline int do_walk_down(struct btrfs_trans_handle *trans,
5970 struct btrfs_root *root,
5971 struct btrfs_path *path,
5972 struct walk_control *wc, int *lookup_info)
5978 struct btrfs_key key;
5979 struct extent_buffer *next;
5980 int level = wc->level;
5984 generation = btrfs_node_ptr_generation(path->nodes[level],
5985 path->slots[level]);
5987 * if the lower level block was created before the snapshot
5988 * was created, we know there is no need to update back refs
5991 if (wc->stage == UPDATE_BACKREF &&
5992 generation <= root->root_key.offset) {
5997 bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]);
5998 blocksize = btrfs_level_size(root, level - 1);
6000 next = btrfs_find_tree_block(root, bytenr, blocksize);
6002 next = btrfs_find_create_tree_block(root, bytenr, blocksize);
6007 btrfs_tree_lock(next);
6008 btrfs_set_lock_blocking(next);
6010 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
6011 &wc->refs[level - 1],
6012 &wc->flags[level - 1]);
6014 BUG_ON(wc->refs[level - 1] == 0);
6017 if (wc->stage == DROP_REFERENCE) {
6018 if (wc->refs[level - 1] > 1) {
6020 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
6023 if (!wc->update_ref ||
6024 generation <= root->root_key.offset)
6027 btrfs_node_key_to_cpu(path->nodes[level], &key,
6028 path->slots[level]);
6029 ret = btrfs_comp_cpu_keys(&key, &wc->update_progress);
6033 wc->stage = UPDATE_BACKREF;
6034 wc->shared_level = level - 1;
6038 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
6042 if (!btrfs_buffer_uptodate(next, generation)) {
6043 btrfs_tree_unlock(next);
6044 free_extent_buffer(next);
6050 if (reada && level == 1)
6051 reada_walk_down(trans, root, wc, path);
6052 next = read_tree_block(root, bytenr, blocksize, generation);
6055 btrfs_tree_lock(next);
6056 btrfs_set_lock_blocking(next);
6060 BUG_ON(level != btrfs_header_level(next));
6061 path->nodes[level] = next;
6062 path->slots[level] = 0;
6063 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6069 wc->refs[level - 1] = 0;
6070 wc->flags[level - 1] = 0;
6071 if (wc->stage == DROP_REFERENCE) {
6072 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
6073 parent = path->nodes[level]->start;
6075 BUG_ON(root->root_key.objectid !=
6076 btrfs_header_owner(path->nodes[level]));
6080 ret = btrfs_free_extent(trans, root, bytenr, blocksize, parent,
6081 root->root_key.objectid, level - 1, 0);
6084 btrfs_tree_unlock(next);
6085 free_extent_buffer(next);
6091 * hepler to process tree block while walking up the tree.
6093 * when wc->stage == DROP_REFERENCE, this function drops
6094 * reference count on the block.
6096 * when wc->stage == UPDATE_BACKREF, this function changes
6097 * wc->stage back to DROP_REFERENCE if we changed wc->stage
6098 * to UPDATE_BACKREF previously while processing the block.
6100 * NOTE: return value 1 means we should stop walking up.
6102 static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
6103 struct btrfs_root *root,
6104 struct btrfs_path *path,
6105 struct walk_control *wc)
6108 int level = wc->level;
6109 struct extent_buffer *eb = path->nodes[level];
6112 if (wc->stage == UPDATE_BACKREF) {
6113 BUG_ON(wc->shared_level < level);
6114 if (level < wc->shared_level)
6117 ret = find_next_key(path, level + 1, &wc->update_progress);
6121 wc->stage = DROP_REFERENCE;
6122 wc->shared_level = -1;
6123 path->slots[level] = 0;
6126 * check reference count again if the block isn't locked.
6127 * we should start walking down the tree again if reference
6130 if (!path->locks[level]) {
6132 btrfs_tree_lock(eb);
6133 btrfs_set_lock_blocking(eb);
6134 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6136 ret = btrfs_lookup_extent_info(trans, root,
6141 BUG_ON(wc->refs[level] == 0);
6142 if (wc->refs[level] == 1) {
6143 btrfs_tree_unlock_rw(eb, path->locks[level]);
6149 /* wc->stage == DROP_REFERENCE */
6150 BUG_ON(wc->refs[level] > 1 && !path->locks[level]);
6152 if (wc->refs[level] == 1) {
6154 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6155 ret = btrfs_dec_ref(trans, root, eb, 1);
6157 ret = btrfs_dec_ref(trans, root, eb, 0);
6160 /* make block locked assertion in clean_tree_block happy */
6161 if (!path->locks[level] &&
6162 btrfs_header_generation(eb) == trans->transid) {
6163 btrfs_tree_lock(eb);
6164 btrfs_set_lock_blocking(eb);
6165 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6167 clean_tree_block(trans, root, eb);
6170 if (eb == root->node) {
6171 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6174 BUG_ON(root->root_key.objectid !=
6175 btrfs_header_owner(eb));
6177 if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6178 parent = path->nodes[level + 1]->start;
6180 BUG_ON(root->root_key.objectid !=
6181 btrfs_header_owner(path->nodes[level + 1]));
6184 btrfs_free_tree_block(trans, root, eb, parent, wc->refs[level] == 1);
6186 wc->refs[level] = 0;
6187 wc->flags[level] = 0;
6191 static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
6192 struct btrfs_root *root,
6193 struct btrfs_path *path,
6194 struct walk_control *wc)
6196 int level = wc->level;
6197 int lookup_info = 1;
6200 while (level >= 0) {
6201 ret = walk_down_proc(trans, root, path, wc, lookup_info);
6208 if (path->slots[level] >=
6209 btrfs_header_nritems(path->nodes[level]))
6212 ret = do_walk_down(trans, root, path, wc, &lookup_info);
6214 path->slots[level]++;
6223 static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
6224 struct btrfs_root *root,
6225 struct btrfs_path *path,
6226 struct walk_control *wc, int max_level)
6228 int level = wc->level;
6231 path->slots[level] = btrfs_header_nritems(path->nodes[level]);
6232 while (level < max_level && path->nodes[level]) {
6234 if (path->slots[level] + 1 <
6235 btrfs_header_nritems(path->nodes[level])) {
6236 path->slots[level]++;
6239 ret = walk_up_proc(trans, root, path, wc);
6243 if (path->locks[level]) {
6244 btrfs_tree_unlock_rw(path->nodes[level],
6245 path->locks[level]);
6246 path->locks[level] = 0;
6248 free_extent_buffer(path->nodes[level]);
6249 path->nodes[level] = NULL;
6257 * drop a subvolume tree.
6259 * this function traverses the tree freeing any blocks that only
6260 * referenced by the tree.
6262 * when a shared tree block is found. this function decreases its
6263 * reference count by one. if update_ref is true, this function
6264 * also make sure backrefs for the shared block and all lower level
6265 * blocks are properly updated.
6267 void btrfs_drop_snapshot(struct btrfs_root *root,
6268 struct btrfs_block_rsv *block_rsv, int update_ref)
6270 struct btrfs_path *path;
6271 struct btrfs_trans_handle *trans;
6272 struct btrfs_root *tree_root = root->fs_info->tree_root;
6273 struct btrfs_root_item *root_item = &root->root_item;
6274 struct walk_control *wc;
6275 struct btrfs_key key;
6280 path = btrfs_alloc_path();
6286 wc = kzalloc(sizeof(*wc), GFP_NOFS);
6288 btrfs_free_path(path);
6293 trans = btrfs_start_transaction(tree_root, 0);
6294 BUG_ON(IS_ERR(trans));
6297 trans->block_rsv = block_rsv;
6299 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
6300 level = btrfs_header_level(root->node);
6301 path->nodes[level] = btrfs_lock_root_node(root);
6302 btrfs_set_lock_blocking(path->nodes[level]);
6303 path->slots[level] = 0;
6304 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6305 memset(&wc->update_progress, 0,
6306 sizeof(wc->update_progress));
6308 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
6309 memcpy(&wc->update_progress, &key,
6310 sizeof(wc->update_progress));
6312 level = root_item->drop_level;
6314 path->lowest_level = level;
6315 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6316 path->lowest_level = 0;
6324 * unlock our path, this is safe because only this
6325 * function is allowed to delete this snapshot
6327 btrfs_unlock_up_safe(path, 0);
6329 level = btrfs_header_level(root->node);
6331 btrfs_tree_lock(path->nodes[level]);
6332 btrfs_set_lock_blocking(path->nodes[level]);
6334 ret = btrfs_lookup_extent_info(trans, root,
6335 path->nodes[level]->start,
6336 path->nodes[level]->len,
6340 BUG_ON(wc->refs[level] == 0);
6342 if (level == root_item->drop_level)
6345 btrfs_tree_unlock(path->nodes[level]);
6346 WARN_ON(wc->refs[level] != 1);
6352 wc->shared_level = -1;
6353 wc->stage = DROP_REFERENCE;
6354 wc->update_ref = update_ref;
6356 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
6359 ret = walk_down_tree(trans, root, path, wc);
6365 ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL);
6372 BUG_ON(wc->stage != DROP_REFERENCE);
6376 if (wc->stage == DROP_REFERENCE) {
6378 btrfs_node_key(path->nodes[level],
6379 &root_item->drop_progress,
6380 path->slots[level]);
6381 root_item->drop_level = level;
6384 BUG_ON(wc->level == 0);
6385 if (btrfs_should_end_transaction(trans, tree_root)) {
6386 ret = btrfs_update_root(trans, tree_root,
6391 btrfs_end_transaction_throttle(trans, tree_root);
6392 trans = btrfs_start_transaction(tree_root, 0);
6393 BUG_ON(IS_ERR(trans));
6395 trans->block_rsv = block_rsv;
6398 btrfs_release_path(path);
6401 ret = btrfs_del_root(trans, tree_root, &root->root_key);
6404 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
6405 ret = btrfs_find_last_root(tree_root, root->root_key.objectid,
6409 /* if we fail to delete the orphan item this time
6410 * around, it'll get picked up the next time.
6412 * The most common failure here is just -ENOENT.
6414 btrfs_del_orphan_item(trans, tree_root,
6415 root->root_key.objectid);
6419 if (root->in_radix) {
6420 btrfs_free_fs_root(tree_root->fs_info, root);
6422 free_extent_buffer(root->node);
6423 free_extent_buffer(root->commit_root);
6427 btrfs_end_transaction_throttle(trans, tree_root);
6429 btrfs_free_path(path);
6432 btrfs_std_error(root->fs_info, err);
6437 * drop subtree rooted at tree block 'node'.
6439 * NOTE: this function will unlock and release tree block 'node'
6441 int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
6442 struct btrfs_root *root,
6443 struct extent_buffer *node,
6444 struct extent_buffer *parent)
6446 struct btrfs_path *path;
6447 struct walk_control *wc;
6453 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
6455 path = btrfs_alloc_path();
6459 wc = kzalloc(sizeof(*wc), GFP_NOFS);
6461 btrfs_free_path(path);
6465 btrfs_assert_tree_locked(parent);
6466 parent_level = btrfs_header_level(parent);
6467 extent_buffer_get(parent);
6468 path->nodes[parent_level] = parent;
6469 path->slots[parent_level] = btrfs_header_nritems(parent);
6471 btrfs_assert_tree_locked(node);
6472 level = btrfs_header_level(node);
6473 path->nodes[level] = node;
6474 path->slots[level] = 0;
6475 path->locks[level] = BTRFS_WRITE_LOCK_BLOCKING;
6477 wc->refs[parent_level] = 1;
6478 wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF;
6480 wc->shared_level = -1;
6481 wc->stage = DROP_REFERENCE;
6484 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
6487 wret = walk_down_tree(trans, root, path, wc);
6493 wret = walk_up_tree(trans, root, path, wc, parent_level);
6501 btrfs_free_path(path);
6505 static u64 update_block_group_flags(struct btrfs_root *root, u64 flags)
6508 u64 stripped = BTRFS_BLOCK_GROUP_RAID0 |
6509 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
6512 * we add in the count of missing devices because we want
6513 * to make sure that any RAID levels on a degraded FS
6514 * continue to be honored.
6516 num_devices = root->fs_info->fs_devices->rw_devices +
6517 root->fs_info->fs_devices->missing_devices;
6519 if (num_devices == 1) {
6520 stripped |= BTRFS_BLOCK_GROUP_DUP;
6521 stripped = flags & ~stripped;
6523 /* turn raid0 into single device chunks */
6524 if (flags & BTRFS_BLOCK_GROUP_RAID0)
6527 /* turn mirroring into duplication */
6528 if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
6529 BTRFS_BLOCK_GROUP_RAID10))
6530 return stripped | BTRFS_BLOCK_GROUP_DUP;
6533 /* they already had raid on here, just return */
6534 if (flags & stripped)
6537 stripped |= BTRFS_BLOCK_GROUP_DUP;
6538 stripped = flags & ~stripped;
6540 /* switch duplicated blocks with raid1 */
6541 if (flags & BTRFS_BLOCK_GROUP_DUP)
6542 return stripped | BTRFS_BLOCK_GROUP_RAID1;
6544 /* turn single device chunks into raid0 */
6545 return stripped | BTRFS_BLOCK_GROUP_RAID0;
6550 static int set_block_group_ro(struct btrfs_block_group_cache *cache, int force)
6552 struct btrfs_space_info *sinfo = cache->space_info;
6554 u64 min_allocable_bytes;
6559 * We need some metadata space and system metadata space for
6560 * allocating chunks in some corner cases until we force to set
6561 * it to be readonly.
6564 (BTRFS_BLOCK_GROUP_SYSTEM | BTRFS_BLOCK_GROUP_METADATA)) &&
6566 min_allocable_bytes = 1 * 1024 * 1024;
6568 min_allocable_bytes = 0;
6570 spin_lock(&sinfo->lock);
6571 spin_lock(&cache->lock);
6578 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
6579 cache->bytes_super - btrfs_block_group_used(&cache->item);
6581 if (sinfo->bytes_used + sinfo->bytes_reserved + sinfo->bytes_pinned +
6582 sinfo->bytes_may_use + sinfo->bytes_readonly + num_bytes +
6583 min_allocable_bytes <= sinfo->total_bytes) {
6584 sinfo->bytes_readonly += num_bytes;
6589 spin_unlock(&cache->lock);
6590 spin_unlock(&sinfo->lock);
6594 int btrfs_set_block_group_ro(struct btrfs_root *root,
6595 struct btrfs_block_group_cache *cache)
6598 struct btrfs_trans_handle *trans;
6604 trans = btrfs_join_transaction(root);
6605 BUG_ON(IS_ERR(trans));
6607 alloc_flags = update_block_group_flags(root, cache->flags);
6608 if (alloc_flags != cache->flags)
6609 do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags,
6612 ret = set_block_group_ro(cache, 0);
6615 alloc_flags = get_alloc_profile(root, cache->space_info->flags);
6616 ret = do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags,
6620 ret = set_block_group_ro(cache, 0);
6622 btrfs_end_transaction(trans, root);
6626 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans,
6627 struct btrfs_root *root, u64 type)
6629 u64 alloc_flags = get_alloc_profile(root, type);
6630 return do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags,
6635 * helper to account the unused space of all the readonly block group in the
6636 * list. takes mirrors into account.
6638 static u64 __btrfs_get_ro_block_group_free_space(struct list_head *groups_list)
6640 struct btrfs_block_group_cache *block_group;
6644 list_for_each_entry(block_group, groups_list, list) {
6645 spin_lock(&block_group->lock);
6647 if (!block_group->ro) {
6648 spin_unlock(&block_group->lock);
6652 if (block_group->flags & (BTRFS_BLOCK_GROUP_RAID1 |
6653 BTRFS_BLOCK_GROUP_RAID10 |
6654 BTRFS_BLOCK_GROUP_DUP))
6659 free_bytes += (block_group->key.offset -
6660 btrfs_block_group_used(&block_group->item)) *
6663 spin_unlock(&block_group->lock);
6670 * helper to account the unused space of all the readonly block group in the
6671 * space_info. takes mirrors into account.
6673 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo)
6678 spin_lock(&sinfo->lock);
6680 for(i = 0; i < BTRFS_NR_RAID_TYPES; i++)
6681 if (!list_empty(&sinfo->block_groups[i]))
6682 free_bytes += __btrfs_get_ro_block_group_free_space(
6683 &sinfo->block_groups[i]);
6685 spin_unlock(&sinfo->lock);
6690 int btrfs_set_block_group_rw(struct btrfs_root *root,
6691 struct btrfs_block_group_cache *cache)
6693 struct btrfs_space_info *sinfo = cache->space_info;
6698 spin_lock(&sinfo->lock);
6699 spin_lock(&cache->lock);
6700 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
6701 cache->bytes_super - btrfs_block_group_used(&cache->item);
6702 sinfo->bytes_readonly -= num_bytes;
6704 spin_unlock(&cache->lock);
6705 spin_unlock(&sinfo->lock);
6710 * checks to see if its even possible to relocate this block group.
6712 * @return - -1 if it's not a good idea to relocate this block group, 0 if its
6713 * ok to go ahead and try.
6715 int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
6717 struct btrfs_block_group_cache *block_group;
6718 struct btrfs_space_info *space_info;
6719 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
6720 struct btrfs_device *device;
6728 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
6730 /* odd, couldn't find the block group, leave it alone */
6734 min_free = btrfs_block_group_used(&block_group->item);
6736 /* no bytes used, we're good */
6740 space_info = block_group->space_info;
6741 spin_lock(&space_info->lock);
6743 full = space_info->full;
6746 * if this is the last block group we have in this space, we can't
6747 * relocate it unless we're able to allocate a new chunk below.
6749 * Otherwise, we need to make sure we have room in the space to handle
6750 * all of the extents from this block group. If we can, we're good
6752 if ((space_info->total_bytes != block_group->key.offset) &&
6753 (space_info->bytes_used + space_info->bytes_reserved +
6754 space_info->bytes_pinned + space_info->bytes_readonly +
6755 min_free < space_info->total_bytes)) {
6756 spin_unlock(&space_info->lock);
6759 spin_unlock(&space_info->lock);
6762 * ok we don't have enough space, but maybe we have free space on our
6763 * devices to allocate new chunks for relocation, so loop through our
6764 * alloc devices and guess if we have enough space. However, if we
6765 * were marked as full, then we know there aren't enough chunks, and we
6780 index = get_block_group_index(block_group);
6785 } else if (index == 1) {
6787 } else if (index == 2) {
6790 } else if (index == 3) {
6791 dev_min = fs_devices->rw_devices;
6792 do_div(min_free, dev_min);
6795 mutex_lock(&root->fs_info->chunk_mutex);
6796 list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
6800 * check to make sure we can actually find a chunk with enough
6801 * space to fit our block group in.
6803 if (device->total_bytes > device->bytes_used + min_free) {
6804 ret = find_free_dev_extent(NULL, device, min_free,
6809 if (dev_nr >= dev_min)
6815 mutex_unlock(&root->fs_info->chunk_mutex);
6817 btrfs_put_block_group(block_group);
6821 static int find_first_block_group(struct btrfs_root *root,
6822 struct btrfs_path *path, struct btrfs_key *key)
6825 struct btrfs_key found_key;
6826 struct extent_buffer *leaf;
6829 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
6834 slot = path->slots[0];
6835 leaf = path->nodes[0];
6836 if (slot >= btrfs_header_nritems(leaf)) {
6837 ret = btrfs_next_leaf(root, path);
6844 btrfs_item_key_to_cpu(leaf, &found_key, slot);
6846 if (found_key.objectid >= key->objectid &&
6847 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
6857 void btrfs_put_block_group_cache(struct btrfs_fs_info *info)
6859 struct btrfs_block_group_cache *block_group;
6863 struct inode *inode;
6865 block_group = btrfs_lookup_first_block_group(info, last);
6866 while (block_group) {
6867 spin_lock(&block_group->lock);
6868 if (block_group->iref)
6870 spin_unlock(&block_group->lock);
6871 block_group = next_block_group(info->tree_root,
6881 inode = block_group->inode;
6882 block_group->iref = 0;
6883 block_group->inode = NULL;
6884 spin_unlock(&block_group->lock);
6886 last = block_group->key.objectid + block_group->key.offset;
6887 btrfs_put_block_group(block_group);
6891 int btrfs_free_block_groups(struct btrfs_fs_info *info)
6893 struct btrfs_block_group_cache *block_group;
6894 struct btrfs_space_info *space_info;
6895 struct btrfs_caching_control *caching_ctl;
6898 down_write(&info->extent_commit_sem);
6899 while (!list_empty(&info->caching_block_groups)) {
6900 caching_ctl = list_entry(info->caching_block_groups.next,
6901 struct btrfs_caching_control, list);
6902 list_del(&caching_ctl->list);
6903 put_caching_control(caching_ctl);
6905 up_write(&info->extent_commit_sem);
6907 spin_lock(&info->block_group_cache_lock);
6908 while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
6909 block_group = rb_entry(n, struct btrfs_block_group_cache,
6911 rb_erase(&block_group->cache_node,
6912 &info->block_group_cache_tree);
6913 spin_unlock(&info->block_group_cache_lock);
6915 down_write(&block_group->space_info->groups_sem);
6916 list_del(&block_group->list);
6917 up_write(&block_group->space_info->groups_sem);
6919 if (block_group->cached == BTRFS_CACHE_STARTED)
6920 wait_block_group_cache_done(block_group);
6923 * We haven't cached this block group, which means we could
6924 * possibly have excluded extents on this block group.
6926 if (block_group->cached == BTRFS_CACHE_NO)
6927 free_excluded_extents(info->extent_root, block_group);
6929 btrfs_remove_free_space_cache(block_group);
6930 btrfs_put_block_group(block_group);
6932 spin_lock(&info->block_group_cache_lock);
6934 spin_unlock(&info->block_group_cache_lock);
6936 /* now that all the block groups are freed, go through and
6937 * free all the space_info structs. This is only called during
6938 * the final stages of unmount, and so we know nobody is
6939 * using them. We call synchronize_rcu() once before we start,
6940 * just to be on the safe side.
6944 release_global_block_rsv(info);
6946 while(!list_empty(&info->space_info)) {
6947 space_info = list_entry(info->space_info.next,
6948 struct btrfs_space_info,
6950 if (space_info->bytes_pinned > 0 ||
6951 space_info->bytes_reserved > 0 ||
6952 space_info->bytes_may_use > 0) {
6954 dump_space_info(space_info, 0, 0);
6956 list_del(&space_info->list);
6962 static void __link_block_group(struct btrfs_space_info *space_info,
6963 struct btrfs_block_group_cache *cache)
6965 int index = get_block_group_index(cache);
6967 down_write(&space_info->groups_sem);
6968 list_add_tail(&cache->list, &space_info->block_groups[index]);
6969 up_write(&space_info->groups_sem);
6972 int btrfs_read_block_groups(struct btrfs_root *root)
6974 struct btrfs_path *path;
6976 struct btrfs_block_group_cache *cache;
6977 struct btrfs_fs_info *info = root->fs_info;
6978 struct btrfs_space_info *space_info;
6979 struct btrfs_key key;
6980 struct btrfs_key found_key;
6981 struct extent_buffer *leaf;
6985 root = info->extent_root;
6988 btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
6989 path = btrfs_alloc_path();
6994 cache_gen = btrfs_super_cache_generation(&root->fs_info->super_copy);
6995 if (cache_gen != 0 &&
6996 btrfs_super_generation(&root->fs_info->super_copy) != cache_gen)
6998 if (btrfs_test_opt(root, CLEAR_CACHE))
7000 if (!btrfs_test_opt(root, SPACE_CACHE) && cache_gen)
7001 printk(KERN_INFO "btrfs: disk space caching is enabled\n");
7004 ret = find_first_block_group(root, path, &key);
7009 leaf = path->nodes[0];
7010 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
7011 cache = kzalloc(sizeof(*cache), GFP_NOFS);
7016 cache->free_space_ctl = kzalloc(sizeof(*cache->free_space_ctl),
7018 if (!cache->free_space_ctl) {
7024 atomic_set(&cache->count, 1);
7025 spin_lock_init(&cache->lock);
7026 cache->fs_info = info;
7027 INIT_LIST_HEAD(&cache->list);
7028 INIT_LIST_HEAD(&cache->cluster_list);
7031 cache->disk_cache_state = BTRFS_DC_CLEAR;
7033 read_extent_buffer(leaf, &cache->item,
7034 btrfs_item_ptr_offset(leaf, path->slots[0]),
7035 sizeof(cache->item));
7036 memcpy(&cache->key, &found_key, sizeof(found_key));
7038 key.objectid = found_key.objectid + found_key.offset;
7039 btrfs_release_path(path);
7040 cache->flags = btrfs_block_group_flags(&cache->item);
7041 cache->sectorsize = root->sectorsize;
7043 btrfs_init_free_space_ctl(cache);
7046 * We need to exclude the super stripes now so that the space
7047 * info has super bytes accounted for, otherwise we'll think
7048 * we have more space than we actually do.
7050 exclude_super_stripes(root, cache);
7053 * check for two cases, either we are full, and therefore
7054 * don't need to bother with the caching work since we won't
7055 * find any space, or we are empty, and we can just add all
7056 * the space in and be done with it. This saves us _alot_ of
7057 * time, particularly in the full case.
7059 if (found_key.offset == btrfs_block_group_used(&cache->item)) {
7060 cache->last_byte_to_unpin = (u64)-1;
7061 cache->cached = BTRFS_CACHE_FINISHED;
7062 free_excluded_extents(root, cache);
7063 } else if (btrfs_block_group_used(&cache->item) == 0) {
7064 cache->last_byte_to_unpin = (u64)-1;
7065 cache->cached = BTRFS_CACHE_FINISHED;
7066 add_new_free_space(cache, root->fs_info,
7068 found_key.objectid +
7070 free_excluded_extents(root, cache);
7073 ret = update_space_info(info, cache->flags, found_key.offset,
7074 btrfs_block_group_used(&cache->item),
7077 cache->space_info = space_info;
7078 spin_lock(&cache->space_info->lock);
7079 cache->space_info->bytes_readonly += cache->bytes_super;
7080 spin_unlock(&cache->space_info->lock);
7082 __link_block_group(space_info, cache);
7084 ret = btrfs_add_block_group_cache(root->fs_info, cache);
7087 set_avail_alloc_bits(root->fs_info, cache->flags);
7088 if (btrfs_chunk_readonly(root, cache->key.objectid))
7089 set_block_group_ro(cache, 1);
7092 list_for_each_entry_rcu(space_info, &root->fs_info->space_info, list) {
7093 if (!(get_alloc_profile(root, space_info->flags) &
7094 (BTRFS_BLOCK_GROUP_RAID10 |
7095 BTRFS_BLOCK_GROUP_RAID1 |
7096 BTRFS_BLOCK_GROUP_DUP)))
7099 * avoid allocating from un-mirrored block group if there are
7100 * mirrored block groups.
7102 list_for_each_entry(cache, &space_info->block_groups[3], list)
7103 set_block_group_ro(cache, 1);
7104 list_for_each_entry(cache, &space_info->block_groups[4], list)
7105 set_block_group_ro(cache, 1);
7108 init_global_block_rsv(info);
7111 btrfs_free_path(path);
7115 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
7116 struct btrfs_root *root, u64 bytes_used,
7117 u64 type, u64 chunk_objectid, u64 chunk_offset,
7121 struct btrfs_root *extent_root;
7122 struct btrfs_block_group_cache *cache;
7124 extent_root = root->fs_info->extent_root;
7126 root->fs_info->last_trans_log_full_commit = trans->transid;
7128 cache = kzalloc(sizeof(*cache), GFP_NOFS);
7131 cache->free_space_ctl = kzalloc(sizeof(*cache->free_space_ctl),
7133 if (!cache->free_space_ctl) {
7138 cache->key.objectid = chunk_offset;
7139 cache->key.offset = size;
7140 cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
7141 cache->sectorsize = root->sectorsize;
7142 cache->fs_info = root->fs_info;
7144 atomic_set(&cache->count, 1);
7145 spin_lock_init(&cache->lock);
7146 INIT_LIST_HEAD(&cache->list);
7147 INIT_LIST_HEAD(&cache->cluster_list);
7149 btrfs_init_free_space_ctl(cache);
7151 btrfs_set_block_group_used(&cache->item, bytes_used);
7152 btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
7153 cache->flags = type;
7154 btrfs_set_block_group_flags(&cache->item, type);
7156 cache->last_byte_to_unpin = (u64)-1;
7157 cache->cached = BTRFS_CACHE_FINISHED;
7158 exclude_super_stripes(root, cache);
7160 add_new_free_space(cache, root->fs_info, chunk_offset,
7161 chunk_offset + size);
7163 free_excluded_extents(root, cache);
7165 ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
7166 &cache->space_info);
7169 spin_lock(&cache->space_info->lock);
7170 cache->space_info->bytes_readonly += cache->bytes_super;
7171 spin_unlock(&cache->space_info->lock);
7173 __link_block_group(cache->space_info, cache);
7175 ret = btrfs_add_block_group_cache(root->fs_info, cache);
7178 ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
7179 sizeof(cache->item));
7182 set_avail_alloc_bits(extent_root->fs_info, type);
7187 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
7188 struct btrfs_root *root, u64 group_start)
7190 struct btrfs_path *path;
7191 struct btrfs_block_group_cache *block_group;
7192 struct btrfs_free_cluster *cluster;
7193 struct btrfs_root *tree_root = root->fs_info->tree_root;
7194 struct btrfs_key key;
7195 struct inode *inode;
7199 root = root->fs_info->extent_root;
7201 block_group = btrfs_lookup_block_group(root->fs_info, group_start);
7202 BUG_ON(!block_group);
7203 BUG_ON(!block_group->ro);
7206 * Free the reserved super bytes from this block group before
7209 free_excluded_extents(root, block_group);
7211 memcpy(&key, &block_group->key, sizeof(key));
7212 if (block_group->flags & (BTRFS_BLOCK_GROUP_DUP |
7213 BTRFS_BLOCK_GROUP_RAID1 |
7214 BTRFS_BLOCK_GROUP_RAID10))
7219 /* make sure this block group isn't part of an allocation cluster */
7220 cluster = &root->fs_info->data_alloc_cluster;
7221 spin_lock(&cluster->refill_lock);
7222 btrfs_return_cluster_to_free_space(block_group, cluster);
7223 spin_unlock(&cluster->refill_lock);
7226 * make sure this block group isn't part of a metadata
7227 * allocation cluster
7229 cluster = &root->fs_info->meta_alloc_cluster;
7230 spin_lock(&cluster->refill_lock);
7231 btrfs_return_cluster_to_free_space(block_group, cluster);
7232 spin_unlock(&cluster->refill_lock);
7234 path = btrfs_alloc_path();
7240 inode = lookup_free_space_inode(root, block_group, path);
7241 if (!IS_ERR(inode)) {
7242 ret = btrfs_orphan_add(trans, inode);
7245 /* One for the block groups ref */
7246 spin_lock(&block_group->lock);
7247 if (block_group->iref) {
7248 block_group->iref = 0;
7249 block_group->inode = NULL;
7250 spin_unlock(&block_group->lock);
7253 spin_unlock(&block_group->lock);
7255 /* One for our lookup ref */
7259 key.objectid = BTRFS_FREE_SPACE_OBJECTID;
7260 key.offset = block_group->key.objectid;
7263 ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1);
7267 btrfs_release_path(path);
7269 ret = btrfs_del_item(trans, tree_root, path);
7272 btrfs_release_path(path);
7275 spin_lock(&root->fs_info->block_group_cache_lock);
7276 rb_erase(&block_group->cache_node,
7277 &root->fs_info->block_group_cache_tree);
7278 spin_unlock(&root->fs_info->block_group_cache_lock);
7280 down_write(&block_group->space_info->groups_sem);
7282 * we must use list_del_init so people can check to see if they
7283 * are still on the list after taking the semaphore
7285 list_del_init(&block_group->list);
7286 up_write(&block_group->space_info->groups_sem);
7288 if (block_group->cached == BTRFS_CACHE_STARTED)
7289 wait_block_group_cache_done(block_group);
7291 btrfs_remove_free_space_cache(block_group);
7293 spin_lock(&block_group->space_info->lock);
7294 block_group->space_info->total_bytes -= block_group->key.offset;
7295 block_group->space_info->bytes_readonly -= block_group->key.offset;
7296 block_group->space_info->disk_total -= block_group->key.offset * factor;
7297 spin_unlock(&block_group->space_info->lock);
7299 memcpy(&key, &block_group->key, sizeof(key));
7301 btrfs_clear_space_info_full(root->fs_info);
7303 btrfs_put_block_group(block_group);
7304 btrfs_put_block_group(block_group);
7306 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
7312 ret = btrfs_del_item(trans, root, path);
7314 btrfs_free_path(path);
7318 int btrfs_init_space_info(struct btrfs_fs_info *fs_info)
7320 struct btrfs_space_info *space_info;
7321 struct btrfs_super_block *disk_super;
7327 disk_super = &fs_info->super_copy;
7328 if (!btrfs_super_root(disk_super))
7331 features = btrfs_super_incompat_flags(disk_super);
7332 if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
7335 flags = BTRFS_BLOCK_GROUP_SYSTEM;
7336 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
7341 flags = BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA;
7342 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
7344 flags = BTRFS_BLOCK_GROUP_METADATA;
7345 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
7349 flags = BTRFS_BLOCK_GROUP_DATA;
7350 ret = update_space_info(fs_info, flags, 0, 0, &space_info);
7356 int btrfs_error_unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
7358 return unpin_extent_range(root, start, end);
7361 int btrfs_error_discard_extent(struct btrfs_root *root, u64 bytenr,
7362 u64 num_bytes, u64 *actual_bytes)
7364 return btrfs_discard_extent(root, bytenr, num_bytes, actual_bytes);
7367 int btrfs_trim_fs(struct btrfs_root *root, struct fstrim_range *range)
7369 struct btrfs_fs_info *fs_info = root->fs_info;
7370 struct btrfs_block_group_cache *cache = NULL;
7377 cache = btrfs_lookup_block_group(fs_info, range->start);
7380 if (cache->key.objectid >= (range->start + range->len)) {
7381 btrfs_put_block_group(cache);
7385 start = max(range->start, cache->key.objectid);
7386 end = min(range->start + range->len,
7387 cache->key.objectid + cache->key.offset);
7389 if (end - start >= range->minlen) {
7390 if (!block_group_cache_done(cache)) {
7391 ret = cache_block_group(cache, NULL, root, 0);
7393 wait_block_group_cache_done(cache);
7395 ret = btrfs_trim_block_group(cache,
7401 trimmed += group_trimmed;
7403 btrfs_put_block_group(cache);
7408 cache = next_block_group(fs_info->tree_root, cache);
7411 range->len = trimmed;