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 static int update_block_group(struct btrfs_trans_handle *trans,
37 struct btrfs_root *root,
38 u64 bytenr, u64 num_bytes, int alloc);
39 static int update_reserved_bytes(struct btrfs_block_group_cache *cache,
40 u64 num_bytes, int reserve, int sinfo);
41 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
42 struct btrfs_root *root,
43 u64 bytenr, u64 num_bytes, u64 parent,
44 u64 root_objectid, u64 owner_objectid,
45 u64 owner_offset, int refs_to_drop,
46 struct btrfs_delayed_extent_op *extra_op);
47 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
48 struct extent_buffer *leaf,
49 struct btrfs_extent_item *ei);
50 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
51 struct btrfs_root *root,
52 u64 parent, u64 root_objectid,
53 u64 flags, u64 owner, u64 offset,
54 struct btrfs_key *ins, int ref_mod);
55 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
56 struct btrfs_root *root,
57 u64 parent, u64 root_objectid,
58 u64 flags, struct btrfs_disk_key *key,
59 int level, struct btrfs_key *ins);
60 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
61 struct btrfs_root *extent_root, u64 alloc_bytes,
62 u64 flags, int force);
63 static int find_next_key(struct btrfs_path *path, int level,
64 struct btrfs_key *key);
65 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
66 int dump_block_groups);
69 block_group_cache_done(struct btrfs_block_group_cache *cache)
72 return cache->cached == BTRFS_CACHE_FINISHED;
75 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
77 return (cache->flags & bits) == bits;
80 void btrfs_get_block_group(struct btrfs_block_group_cache *cache)
82 atomic_inc(&cache->count);
85 void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
87 if (atomic_dec_and_test(&cache->count)) {
88 WARN_ON(cache->pinned > 0);
89 WARN_ON(cache->reserved > 0);
90 WARN_ON(cache->reserved_pinned > 0);
96 * this adds the block group to the fs_info rb tree for the block group
99 static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
100 struct btrfs_block_group_cache *block_group)
103 struct rb_node *parent = NULL;
104 struct btrfs_block_group_cache *cache;
106 spin_lock(&info->block_group_cache_lock);
107 p = &info->block_group_cache_tree.rb_node;
111 cache = rb_entry(parent, struct btrfs_block_group_cache,
113 if (block_group->key.objectid < cache->key.objectid) {
115 } else if (block_group->key.objectid > cache->key.objectid) {
118 spin_unlock(&info->block_group_cache_lock);
123 rb_link_node(&block_group->cache_node, parent, p);
124 rb_insert_color(&block_group->cache_node,
125 &info->block_group_cache_tree);
126 spin_unlock(&info->block_group_cache_lock);
132 * This will return the block group at or after bytenr if contains is 0, else
133 * it will return the block group that contains the bytenr
135 static struct btrfs_block_group_cache *
136 block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
139 struct btrfs_block_group_cache *cache, *ret = NULL;
143 spin_lock(&info->block_group_cache_lock);
144 n = info->block_group_cache_tree.rb_node;
147 cache = rb_entry(n, struct btrfs_block_group_cache,
149 end = cache->key.objectid + cache->key.offset - 1;
150 start = cache->key.objectid;
152 if (bytenr < start) {
153 if (!contains && (!ret || start < ret->key.objectid))
156 } else if (bytenr > start) {
157 if (contains && bytenr <= end) {
168 btrfs_get_block_group(ret);
169 spin_unlock(&info->block_group_cache_lock);
174 static int add_excluded_extent(struct btrfs_root *root,
175 u64 start, u64 num_bytes)
177 u64 end = start + num_bytes - 1;
178 set_extent_bits(&root->fs_info->freed_extents[0],
179 start, end, EXTENT_UPTODATE, GFP_NOFS);
180 set_extent_bits(&root->fs_info->freed_extents[1],
181 start, end, EXTENT_UPTODATE, GFP_NOFS);
185 static void free_excluded_extents(struct btrfs_root *root,
186 struct btrfs_block_group_cache *cache)
190 start = cache->key.objectid;
191 end = start + cache->key.offset - 1;
193 clear_extent_bits(&root->fs_info->freed_extents[0],
194 start, end, EXTENT_UPTODATE, GFP_NOFS);
195 clear_extent_bits(&root->fs_info->freed_extents[1],
196 start, end, EXTENT_UPTODATE, GFP_NOFS);
199 static int exclude_super_stripes(struct btrfs_root *root,
200 struct btrfs_block_group_cache *cache)
207 if (cache->key.objectid < BTRFS_SUPER_INFO_OFFSET) {
208 stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->key.objectid;
209 cache->bytes_super += stripe_len;
210 ret = add_excluded_extent(root, cache->key.objectid,
215 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
216 bytenr = btrfs_sb_offset(i);
217 ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
218 cache->key.objectid, bytenr,
219 0, &logical, &nr, &stripe_len);
223 cache->bytes_super += stripe_len;
224 ret = add_excluded_extent(root, logical[nr],
234 static struct btrfs_caching_control *
235 get_caching_control(struct btrfs_block_group_cache *cache)
237 struct btrfs_caching_control *ctl;
239 spin_lock(&cache->lock);
240 if (cache->cached != BTRFS_CACHE_STARTED) {
241 spin_unlock(&cache->lock);
245 /* We're loading it the fast way, so we don't have a caching_ctl. */
246 if (!cache->caching_ctl) {
247 spin_unlock(&cache->lock);
251 ctl = cache->caching_ctl;
252 atomic_inc(&ctl->count);
253 spin_unlock(&cache->lock);
257 static void put_caching_control(struct btrfs_caching_control *ctl)
259 if (atomic_dec_and_test(&ctl->count))
264 * this is only called by cache_block_group, since we could have freed extents
265 * we need to check the pinned_extents for any extents that can't be used yet
266 * since their free space will be released as soon as the transaction commits.
268 static u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
269 struct btrfs_fs_info *info, u64 start, u64 end)
271 u64 extent_start, extent_end, size, total_added = 0;
274 while (start < end) {
275 ret = find_first_extent_bit(info->pinned_extents, start,
276 &extent_start, &extent_end,
277 EXTENT_DIRTY | EXTENT_UPTODATE);
281 if (extent_start <= start) {
282 start = extent_end + 1;
283 } else if (extent_start > start && extent_start < end) {
284 size = extent_start - start;
286 ret = btrfs_add_free_space(block_group, start,
289 start = extent_end + 1;
298 ret = btrfs_add_free_space(block_group, start, size);
305 static int caching_kthread(void *data)
307 struct btrfs_block_group_cache *block_group = data;
308 struct btrfs_fs_info *fs_info = block_group->fs_info;
309 struct btrfs_caching_control *caching_ctl = block_group->caching_ctl;
310 struct btrfs_root *extent_root = fs_info->extent_root;
311 struct btrfs_path *path;
312 struct extent_buffer *leaf;
313 struct btrfs_key key;
319 path = btrfs_alloc_path();
323 exclude_super_stripes(extent_root, block_group);
324 spin_lock(&block_group->space_info->lock);
325 block_group->space_info->bytes_readonly += block_group->bytes_super;
326 spin_unlock(&block_group->space_info->lock);
328 last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
331 * We don't want to deadlock with somebody trying to allocate a new
332 * extent for the extent root while also trying to search the extent
333 * root to add free space. So we skip locking and search the commit
334 * root, since its read-only
336 path->skip_locking = 1;
337 path->search_commit_root = 1;
342 key.type = BTRFS_EXTENT_ITEM_KEY;
344 mutex_lock(&caching_ctl->mutex);
345 /* need to make sure the commit_root doesn't disappear */
346 down_read(&fs_info->extent_commit_sem);
348 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
352 leaf = path->nodes[0];
353 nritems = btrfs_header_nritems(leaf);
357 if (fs_info->closing > 1) {
362 if (path->slots[0] < nritems) {
363 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
365 ret = find_next_key(path, 0, &key);
369 caching_ctl->progress = last;
370 btrfs_release_path(extent_root, path);
371 up_read(&fs_info->extent_commit_sem);
372 mutex_unlock(&caching_ctl->mutex);
373 if (btrfs_transaction_in_commit(fs_info))
380 if (key.objectid < block_group->key.objectid) {
385 if (key.objectid >= block_group->key.objectid +
386 block_group->key.offset)
389 if (key.type == BTRFS_EXTENT_ITEM_KEY) {
390 total_found += add_new_free_space(block_group,
393 last = key.objectid + key.offset;
395 if (total_found > (1024 * 1024 * 2)) {
397 wake_up(&caching_ctl->wait);
404 total_found += add_new_free_space(block_group, fs_info, last,
405 block_group->key.objectid +
406 block_group->key.offset);
407 caching_ctl->progress = (u64)-1;
409 spin_lock(&block_group->lock);
410 block_group->caching_ctl = NULL;
411 block_group->cached = BTRFS_CACHE_FINISHED;
412 spin_unlock(&block_group->lock);
415 btrfs_free_path(path);
416 up_read(&fs_info->extent_commit_sem);
418 free_excluded_extents(extent_root, block_group);
420 mutex_unlock(&caching_ctl->mutex);
421 wake_up(&caching_ctl->wait);
423 put_caching_control(caching_ctl);
424 atomic_dec(&block_group->space_info->caching_threads);
425 btrfs_put_block_group(block_group);
430 static int cache_block_group(struct btrfs_block_group_cache *cache,
431 struct btrfs_trans_handle *trans,
434 struct btrfs_fs_info *fs_info = cache->fs_info;
435 struct btrfs_caching_control *caching_ctl;
436 struct task_struct *tsk;
440 if (cache->cached != BTRFS_CACHE_NO)
444 * We can't do the read from on-disk cache during a commit since we need
445 * to have the normal tree locking.
447 if (!trans->transaction->in_commit) {
448 spin_lock(&cache->lock);
449 if (cache->cached != BTRFS_CACHE_NO) {
450 spin_unlock(&cache->lock);
453 cache->cached = BTRFS_CACHE_STARTED;
454 spin_unlock(&cache->lock);
456 ret = load_free_space_cache(fs_info, cache);
458 spin_lock(&cache->lock);
460 cache->cached = BTRFS_CACHE_FINISHED;
461 cache->last_byte_to_unpin = (u64)-1;
463 cache->cached = BTRFS_CACHE_NO;
465 spin_unlock(&cache->lock);
473 caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_KERNEL);
474 BUG_ON(!caching_ctl);
476 INIT_LIST_HEAD(&caching_ctl->list);
477 mutex_init(&caching_ctl->mutex);
478 init_waitqueue_head(&caching_ctl->wait);
479 caching_ctl->block_group = cache;
480 caching_ctl->progress = cache->key.objectid;
481 /* one for caching kthread, one for caching block group list */
482 atomic_set(&caching_ctl->count, 2);
484 spin_lock(&cache->lock);
485 if (cache->cached != BTRFS_CACHE_NO) {
486 spin_unlock(&cache->lock);
490 cache->caching_ctl = caching_ctl;
491 cache->cached = BTRFS_CACHE_STARTED;
492 spin_unlock(&cache->lock);
494 down_write(&fs_info->extent_commit_sem);
495 list_add_tail(&caching_ctl->list, &fs_info->caching_block_groups);
496 up_write(&fs_info->extent_commit_sem);
498 atomic_inc(&cache->space_info->caching_threads);
499 btrfs_get_block_group(cache);
501 tsk = kthread_run(caching_kthread, cache, "btrfs-cache-%llu\n",
502 cache->key.objectid);
505 printk(KERN_ERR "error running thread %d\n", ret);
513 * return the block group that starts at or after bytenr
515 static struct btrfs_block_group_cache *
516 btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr)
518 struct btrfs_block_group_cache *cache;
520 cache = block_group_cache_tree_search(info, bytenr, 0);
526 * return the block group that contains the given bytenr
528 struct btrfs_block_group_cache *btrfs_lookup_block_group(
529 struct btrfs_fs_info *info,
532 struct btrfs_block_group_cache *cache;
534 cache = block_group_cache_tree_search(info, bytenr, 1);
539 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
542 struct list_head *head = &info->space_info;
543 struct btrfs_space_info *found;
545 flags &= BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_SYSTEM |
546 BTRFS_BLOCK_GROUP_METADATA;
549 list_for_each_entry_rcu(found, head, list) {
550 if (found->flags & flags) {
560 * after adding space to the filesystem, we need to clear the full flags
561 * on all the space infos.
563 void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
565 struct list_head *head = &info->space_info;
566 struct btrfs_space_info *found;
569 list_for_each_entry_rcu(found, head, list)
574 static u64 div_factor(u64 num, int factor)
583 static u64 div_factor_fine(u64 num, int factor)
592 u64 btrfs_find_block_group(struct btrfs_root *root,
593 u64 search_start, u64 search_hint, int owner)
595 struct btrfs_block_group_cache *cache;
597 u64 last = max(search_hint, search_start);
604 cache = btrfs_lookup_first_block_group(root->fs_info, last);
608 spin_lock(&cache->lock);
609 last = cache->key.objectid + cache->key.offset;
610 used = btrfs_block_group_used(&cache->item);
612 if ((full_search || !cache->ro) &&
613 block_group_bits(cache, BTRFS_BLOCK_GROUP_METADATA)) {
614 if (used + cache->pinned + cache->reserved <
615 div_factor(cache->key.offset, factor)) {
616 group_start = cache->key.objectid;
617 spin_unlock(&cache->lock);
618 btrfs_put_block_group(cache);
622 spin_unlock(&cache->lock);
623 btrfs_put_block_group(cache);
631 if (!full_search && factor < 10) {
641 /* simple helper to search for an existing extent at a given offset */
642 int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len)
645 struct btrfs_key key;
646 struct btrfs_path *path;
648 path = btrfs_alloc_path();
650 key.objectid = start;
652 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
653 ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path,
655 btrfs_free_path(path);
660 * helper function to lookup reference count and flags of extent.
662 * the head node for delayed ref is used to store the sum of all the
663 * reference count modifications queued up in the rbtree. the head
664 * node may also store the extent flags to set. This way you can check
665 * to see what the reference count and extent flags would be if all of
666 * the delayed refs are not processed.
668 int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
669 struct btrfs_root *root, u64 bytenr,
670 u64 num_bytes, u64 *refs, u64 *flags)
672 struct btrfs_delayed_ref_head *head;
673 struct btrfs_delayed_ref_root *delayed_refs;
674 struct btrfs_path *path;
675 struct btrfs_extent_item *ei;
676 struct extent_buffer *leaf;
677 struct btrfs_key key;
683 path = btrfs_alloc_path();
687 key.objectid = bytenr;
688 key.type = BTRFS_EXTENT_ITEM_KEY;
689 key.offset = num_bytes;
691 path->skip_locking = 1;
692 path->search_commit_root = 1;
695 ret = btrfs_search_slot(trans, root->fs_info->extent_root,
701 leaf = path->nodes[0];
702 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
703 if (item_size >= sizeof(*ei)) {
704 ei = btrfs_item_ptr(leaf, path->slots[0],
705 struct btrfs_extent_item);
706 num_refs = btrfs_extent_refs(leaf, ei);
707 extent_flags = btrfs_extent_flags(leaf, ei);
709 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
710 struct btrfs_extent_item_v0 *ei0;
711 BUG_ON(item_size != sizeof(*ei0));
712 ei0 = btrfs_item_ptr(leaf, path->slots[0],
713 struct btrfs_extent_item_v0);
714 num_refs = btrfs_extent_refs_v0(leaf, ei0);
715 /* FIXME: this isn't correct for data */
716 extent_flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
721 BUG_ON(num_refs == 0);
731 delayed_refs = &trans->transaction->delayed_refs;
732 spin_lock(&delayed_refs->lock);
733 head = btrfs_find_delayed_ref_head(trans, bytenr);
735 if (!mutex_trylock(&head->mutex)) {
736 atomic_inc(&head->node.refs);
737 spin_unlock(&delayed_refs->lock);
739 btrfs_release_path(root->fs_info->extent_root, path);
741 mutex_lock(&head->mutex);
742 mutex_unlock(&head->mutex);
743 btrfs_put_delayed_ref(&head->node);
746 if (head->extent_op && head->extent_op->update_flags)
747 extent_flags |= head->extent_op->flags_to_set;
749 BUG_ON(num_refs == 0);
751 num_refs += head->node.ref_mod;
752 mutex_unlock(&head->mutex);
754 spin_unlock(&delayed_refs->lock);
756 WARN_ON(num_refs == 0);
760 *flags = extent_flags;
762 btrfs_free_path(path);
767 * Back reference rules. Back refs have three main goals:
769 * 1) differentiate between all holders of references to an extent so that
770 * when a reference is dropped we can make sure it was a valid reference
771 * before freeing the extent.
773 * 2) Provide enough information to quickly find the holders of an extent
774 * if we notice a given block is corrupted or bad.
776 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
777 * maintenance. This is actually the same as #2, but with a slightly
778 * different use case.
780 * There are two kinds of back refs. The implicit back refs is optimized
781 * for pointers in non-shared tree blocks. For a given pointer in a block,
782 * back refs of this kind provide information about the block's owner tree
783 * and the pointer's key. These information allow us to find the block by
784 * b-tree searching. The full back refs is for pointers in tree blocks not
785 * referenced by their owner trees. The location of tree block is recorded
786 * in the back refs. Actually the full back refs is generic, and can be
787 * used in all cases the implicit back refs is used. The major shortcoming
788 * of the full back refs is its overhead. Every time a tree block gets
789 * COWed, we have to update back refs entry for all pointers in it.
791 * For a newly allocated tree block, we use implicit back refs for
792 * pointers in it. This means most tree related operations only involve
793 * implicit back refs. For a tree block created in old transaction, the
794 * only way to drop a reference to it is COW it. So we can detect the
795 * event that tree block loses its owner tree's reference and do the
796 * back refs conversion.
798 * When a tree block is COW'd through a tree, there are four cases:
800 * The reference count of the block is one and the tree is the block's
801 * owner tree. Nothing to do in this case.
803 * The reference count of the block is one and the tree is not the
804 * block's owner tree. In this case, full back refs is used for pointers
805 * in the block. Remove these full back refs, add implicit back refs for
806 * every pointers in the new block.
808 * The reference count of the block is greater than one and the tree is
809 * the block's owner tree. In this case, implicit back refs is used for
810 * pointers in the block. Add full back refs for every pointers in the
811 * block, increase lower level extents' reference counts. The original
812 * implicit back refs are entailed to the new block.
814 * The reference count of the block is greater than one and the tree is
815 * not the block's owner tree. Add implicit back refs for every pointer in
816 * the new block, increase lower level extents' reference count.
818 * Back Reference Key composing:
820 * The key objectid corresponds to the first byte in the extent,
821 * The key type is used to differentiate between types of back refs.
822 * There are different meanings of the key offset for different types
825 * File extents can be referenced by:
827 * - multiple snapshots, subvolumes, or different generations in one subvol
828 * - different files inside a single subvolume
829 * - different offsets inside a file (bookend extents in file.c)
831 * The extent ref structure for the implicit back refs has fields for:
833 * - Objectid of the subvolume root
834 * - objectid of the file holding the reference
835 * - original offset in the file
836 * - how many bookend extents
838 * The key offset for the implicit back refs is hash of the first
841 * The extent ref structure for the full back refs has field for:
843 * - number of pointers in the tree leaf
845 * The key offset for the implicit back refs is the first byte of
848 * When a file extent is allocated, The implicit back refs is used.
849 * the fields are filled in:
851 * (root_key.objectid, inode objectid, offset in file, 1)
853 * When a file extent is removed file truncation, we find the
854 * corresponding implicit back refs and check the following fields:
856 * (btrfs_header_owner(leaf), inode objectid, offset in file)
858 * Btree extents can be referenced by:
860 * - Different subvolumes
862 * Both the implicit back refs and the full back refs for tree blocks
863 * only consist of key. The key offset for the implicit back refs is
864 * objectid of block's owner tree. The key offset for the full back refs
865 * is the first byte of parent block.
867 * When implicit back refs is used, information about the lowest key and
868 * level of the tree block are required. These information are stored in
869 * tree block info structure.
872 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
873 static int convert_extent_item_v0(struct btrfs_trans_handle *trans,
874 struct btrfs_root *root,
875 struct btrfs_path *path,
876 u64 owner, u32 extra_size)
878 struct btrfs_extent_item *item;
879 struct btrfs_extent_item_v0 *ei0;
880 struct btrfs_extent_ref_v0 *ref0;
881 struct btrfs_tree_block_info *bi;
882 struct extent_buffer *leaf;
883 struct btrfs_key key;
884 struct btrfs_key found_key;
885 u32 new_size = sizeof(*item);
889 leaf = path->nodes[0];
890 BUG_ON(btrfs_item_size_nr(leaf, path->slots[0]) != sizeof(*ei0));
892 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
893 ei0 = btrfs_item_ptr(leaf, path->slots[0],
894 struct btrfs_extent_item_v0);
895 refs = btrfs_extent_refs_v0(leaf, ei0);
897 if (owner == (u64)-1) {
899 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
900 ret = btrfs_next_leaf(root, path);
904 leaf = path->nodes[0];
906 btrfs_item_key_to_cpu(leaf, &found_key,
908 BUG_ON(key.objectid != found_key.objectid);
909 if (found_key.type != BTRFS_EXTENT_REF_V0_KEY) {
913 ref0 = btrfs_item_ptr(leaf, path->slots[0],
914 struct btrfs_extent_ref_v0);
915 owner = btrfs_ref_objectid_v0(leaf, ref0);
919 btrfs_release_path(root, path);
921 if (owner < BTRFS_FIRST_FREE_OBJECTID)
922 new_size += sizeof(*bi);
924 new_size -= sizeof(*ei0);
925 ret = btrfs_search_slot(trans, root, &key, path,
926 new_size + extra_size, 1);
931 ret = btrfs_extend_item(trans, root, path, new_size);
934 leaf = path->nodes[0];
935 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
936 btrfs_set_extent_refs(leaf, item, refs);
937 /* FIXME: get real generation */
938 btrfs_set_extent_generation(leaf, item, 0);
939 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
940 btrfs_set_extent_flags(leaf, item,
941 BTRFS_EXTENT_FLAG_TREE_BLOCK |
942 BTRFS_BLOCK_FLAG_FULL_BACKREF);
943 bi = (struct btrfs_tree_block_info *)(item + 1);
944 /* FIXME: get first key of the block */
945 memset_extent_buffer(leaf, 0, (unsigned long)bi, sizeof(*bi));
946 btrfs_set_tree_block_level(leaf, bi, (int)owner);
948 btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_DATA);
950 btrfs_mark_buffer_dirty(leaf);
955 static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
957 u32 high_crc = ~(u32)0;
958 u32 low_crc = ~(u32)0;
961 lenum = cpu_to_le64(root_objectid);
962 high_crc = crc32c(high_crc, &lenum, sizeof(lenum));
963 lenum = cpu_to_le64(owner);
964 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
965 lenum = cpu_to_le64(offset);
966 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
968 return ((u64)high_crc << 31) ^ (u64)low_crc;
971 static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
972 struct btrfs_extent_data_ref *ref)
974 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
975 btrfs_extent_data_ref_objectid(leaf, ref),
976 btrfs_extent_data_ref_offset(leaf, ref));
979 static int match_extent_data_ref(struct extent_buffer *leaf,
980 struct btrfs_extent_data_ref *ref,
981 u64 root_objectid, u64 owner, u64 offset)
983 if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
984 btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
985 btrfs_extent_data_ref_offset(leaf, ref) != offset)
990 static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
991 struct btrfs_root *root,
992 struct btrfs_path *path,
993 u64 bytenr, u64 parent,
995 u64 owner, u64 offset)
997 struct btrfs_key key;
998 struct btrfs_extent_data_ref *ref;
999 struct extent_buffer *leaf;
1005 key.objectid = bytenr;
1007 key.type = BTRFS_SHARED_DATA_REF_KEY;
1008 key.offset = parent;
1010 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1011 key.offset = hash_extent_data_ref(root_objectid,
1016 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1025 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1026 key.type = BTRFS_EXTENT_REF_V0_KEY;
1027 btrfs_release_path(root, path);
1028 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1039 leaf = path->nodes[0];
1040 nritems = btrfs_header_nritems(leaf);
1042 if (path->slots[0] >= nritems) {
1043 ret = btrfs_next_leaf(root, path);
1049 leaf = path->nodes[0];
1050 nritems = btrfs_header_nritems(leaf);
1054 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1055 if (key.objectid != bytenr ||
1056 key.type != BTRFS_EXTENT_DATA_REF_KEY)
1059 ref = btrfs_item_ptr(leaf, path->slots[0],
1060 struct btrfs_extent_data_ref);
1062 if (match_extent_data_ref(leaf, ref, root_objectid,
1065 btrfs_release_path(root, path);
1077 static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
1078 struct btrfs_root *root,
1079 struct btrfs_path *path,
1080 u64 bytenr, u64 parent,
1081 u64 root_objectid, u64 owner,
1082 u64 offset, int refs_to_add)
1084 struct btrfs_key key;
1085 struct extent_buffer *leaf;
1090 key.objectid = bytenr;
1092 key.type = BTRFS_SHARED_DATA_REF_KEY;
1093 key.offset = parent;
1094 size = sizeof(struct btrfs_shared_data_ref);
1096 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1097 key.offset = hash_extent_data_ref(root_objectid,
1099 size = sizeof(struct btrfs_extent_data_ref);
1102 ret = btrfs_insert_empty_item(trans, root, path, &key, size);
1103 if (ret && ret != -EEXIST)
1106 leaf = path->nodes[0];
1108 struct btrfs_shared_data_ref *ref;
1109 ref = btrfs_item_ptr(leaf, path->slots[0],
1110 struct btrfs_shared_data_ref);
1112 btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
1114 num_refs = btrfs_shared_data_ref_count(leaf, ref);
1115 num_refs += refs_to_add;
1116 btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
1119 struct btrfs_extent_data_ref *ref;
1120 while (ret == -EEXIST) {
1121 ref = btrfs_item_ptr(leaf, path->slots[0],
1122 struct btrfs_extent_data_ref);
1123 if (match_extent_data_ref(leaf, ref, root_objectid,
1126 btrfs_release_path(root, path);
1128 ret = btrfs_insert_empty_item(trans, root, path, &key,
1130 if (ret && ret != -EEXIST)
1133 leaf = path->nodes[0];
1135 ref = btrfs_item_ptr(leaf, path->slots[0],
1136 struct btrfs_extent_data_ref);
1138 btrfs_set_extent_data_ref_root(leaf, ref,
1140 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
1141 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
1142 btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
1144 num_refs = btrfs_extent_data_ref_count(leaf, ref);
1145 num_refs += refs_to_add;
1146 btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
1149 btrfs_mark_buffer_dirty(leaf);
1152 btrfs_release_path(root, path);
1156 static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
1157 struct btrfs_root *root,
1158 struct btrfs_path *path,
1161 struct btrfs_key key;
1162 struct btrfs_extent_data_ref *ref1 = NULL;
1163 struct btrfs_shared_data_ref *ref2 = NULL;
1164 struct extent_buffer *leaf;
1168 leaf = path->nodes[0];
1169 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1171 if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1172 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1173 struct btrfs_extent_data_ref);
1174 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1175 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1176 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1177 struct btrfs_shared_data_ref);
1178 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1179 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1180 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1181 struct btrfs_extent_ref_v0 *ref0;
1182 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1183 struct btrfs_extent_ref_v0);
1184 num_refs = btrfs_ref_count_v0(leaf, ref0);
1190 BUG_ON(num_refs < refs_to_drop);
1191 num_refs -= refs_to_drop;
1193 if (num_refs == 0) {
1194 ret = btrfs_del_item(trans, root, path);
1196 if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
1197 btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
1198 else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
1199 btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
1200 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1202 struct btrfs_extent_ref_v0 *ref0;
1203 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1204 struct btrfs_extent_ref_v0);
1205 btrfs_set_ref_count_v0(leaf, ref0, num_refs);
1208 btrfs_mark_buffer_dirty(leaf);
1213 static noinline u32 extent_data_ref_count(struct btrfs_root *root,
1214 struct btrfs_path *path,
1215 struct btrfs_extent_inline_ref *iref)
1217 struct btrfs_key key;
1218 struct extent_buffer *leaf;
1219 struct btrfs_extent_data_ref *ref1;
1220 struct btrfs_shared_data_ref *ref2;
1223 leaf = path->nodes[0];
1224 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1226 if (btrfs_extent_inline_ref_type(leaf, iref) ==
1227 BTRFS_EXTENT_DATA_REF_KEY) {
1228 ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
1229 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1231 ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
1232 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1234 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1235 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1236 struct btrfs_extent_data_ref);
1237 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1238 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1239 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1240 struct btrfs_shared_data_ref);
1241 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1242 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1243 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1244 struct btrfs_extent_ref_v0 *ref0;
1245 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1246 struct btrfs_extent_ref_v0);
1247 num_refs = btrfs_ref_count_v0(leaf, ref0);
1255 static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
1256 struct btrfs_root *root,
1257 struct btrfs_path *path,
1258 u64 bytenr, u64 parent,
1261 struct btrfs_key key;
1264 key.objectid = bytenr;
1266 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1267 key.offset = parent;
1269 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1270 key.offset = root_objectid;
1273 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1276 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1277 if (ret == -ENOENT && parent) {
1278 btrfs_release_path(root, path);
1279 key.type = BTRFS_EXTENT_REF_V0_KEY;
1280 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1288 static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
1289 struct btrfs_root *root,
1290 struct btrfs_path *path,
1291 u64 bytenr, u64 parent,
1294 struct btrfs_key key;
1297 key.objectid = bytenr;
1299 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1300 key.offset = parent;
1302 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1303 key.offset = root_objectid;
1306 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1307 btrfs_release_path(root, path);
1311 static inline int extent_ref_type(u64 parent, u64 owner)
1314 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1316 type = BTRFS_SHARED_BLOCK_REF_KEY;
1318 type = BTRFS_TREE_BLOCK_REF_KEY;
1321 type = BTRFS_SHARED_DATA_REF_KEY;
1323 type = BTRFS_EXTENT_DATA_REF_KEY;
1328 static int find_next_key(struct btrfs_path *path, int level,
1329 struct btrfs_key *key)
1332 for (; level < BTRFS_MAX_LEVEL; level++) {
1333 if (!path->nodes[level])
1335 if (path->slots[level] + 1 >=
1336 btrfs_header_nritems(path->nodes[level]))
1339 btrfs_item_key_to_cpu(path->nodes[level], key,
1340 path->slots[level] + 1);
1342 btrfs_node_key_to_cpu(path->nodes[level], key,
1343 path->slots[level] + 1);
1350 * look for inline back ref. if back ref is found, *ref_ret is set
1351 * to the address of inline back ref, and 0 is returned.
1353 * if back ref isn't found, *ref_ret is set to the address where it
1354 * should be inserted, and -ENOENT is returned.
1356 * if insert is true and there are too many inline back refs, the path
1357 * points to the extent item, and -EAGAIN is returned.
1359 * NOTE: inline back refs are ordered in the same way that back ref
1360 * items in the tree are ordered.
1362 static noinline_for_stack
1363 int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
1364 struct btrfs_root *root,
1365 struct btrfs_path *path,
1366 struct btrfs_extent_inline_ref **ref_ret,
1367 u64 bytenr, u64 num_bytes,
1368 u64 parent, u64 root_objectid,
1369 u64 owner, u64 offset, int insert)
1371 struct btrfs_key key;
1372 struct extent_buffer *leaf;
1373 struct btrfs_extent_item *ei;
1374 struct btrfs_extent_inline_ref *iref;
1385 key.objectid = bytenr;
1386 key.type = BTRFS_EXTENT_ITEM_KEY;
1387 key.offset = num_bytes;
1389 want = extent_ref_type(parent, owner);
1391 extra_size = btrfs_extent_inline_ref_size(want);
1392 path->keep_locks = 1;
1395 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
1402 leaf = path->nodes[0];
1403 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1404 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1405 if (item_size < sizeof(*ei)) {
1410 ret = convert_extent_item_v0(trans, root, path, owner,
1416 leaf = path->nodes[0];
1417 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1420 BUG_ON(item_size < sizeof(*ei));
1422 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1423 flags = btrfs_extent_flags(leaf, ei);
1425 ptr = (unsigned long)(ei + 1);
1426 end = (unsigned long)ei + item_size;
1428 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
1429 ptr += sizeof(struct btrfs_tree_block_info);
1432 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_DATA));
1441 iref = (struct btrfs_extent_inline_ref *)ptr;
1442 type = btrfs_extent_inline_ref_type(leaf, iref);
1446 ptr += btrfs_extent_inline_ref_size(type);
1450 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1451 struct btrfs_extent_data_ref *dref;
1452 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1453 if (match_extent_data_ref(leaf, dref, root_objectid,
1458 if (hash_extent_data_ref_item(leaf, dref) <
1459 hash_extent_data_ref(root_objectid, owner, offset))
1463 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1465 if (parent == ref_offset) {
1469 if (ref_offset < parent)
1472 if (root_objectid == ref_offset) {
1476 if (ref_offset < root_objectid)
1480 ptr += btrfs_extent_inline_ref_size(type);
1482 if (err == -ENOENT && insert) {
1483 if (item_size + extra_size >=
1484 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
1489 * To add new inline back ref, we have to make sure
1490 * there is no corresponding back ref item.
1491 * For simplicity, we just do not add new inline back
1492 * ref if there is any kind of item for this block
1494 if (find_next_key(path, 0, &key) == 0 &&
1495 key.objectid == bytenr &&
1496 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
1501 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
1504 path->keep_locks = 0;
1505 btrfs_unlock_up_safe(path, 1);
1511 * helper to add new inline back ref
1513 static noinline_for_stack
1514 int setup_inline_extent_backref(struct btrfs_trans_handle *trans,
1515 struct btrfs_root *root,
1516 struct btrfs_path *path,
1517 struct btrfs_extent_inline_ref *iref,
1518 u64 parent, u64 root_objectid,
1519 u64 owner, u64 offset, int refs_to_add,
1520 struct btrfs_delayed_extent_op *extent_op)
1522 struct extent_buffer *leaf;
1523 struct btrfs_extent_item *ei;
1526 unsigned long item_offset;
1532 leaf = path->nodes[0];
1533 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1534 item_offset = (unsigned long)iref - (unsigned long)ei;
1536 type = extent_ref_type(parent, owner);
1537 size = btrfs_extent_inline_ref_size(type);
1539 ret = btrfs_extend_item(trans, root, path, size);
1542 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1543 refs = btrfs_extent_refs(leaf, ei);
1544 refs += refs_to_add;
1545 btrfs_set_extent_refs(leaf, ei, refs);
1547 __run_delayed_extent_op(extent_op, leaf, ei);
1549 ptr = (unsigned long)ei + item_offset;
1550 end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
1551 if (ptr < end - size)
1552 memmove_extent_buffer(leaf, ptr + size, ptr,
1555 iref = (struct btrfs_extent_inline_ref *)ptr;
1556 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1557 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1558 struct btrfs_extent_data_ref *dref;
1559 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1560 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1561 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1562 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1563 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1564 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1565 struct btrfs_shared_data_ref *sref;
1566 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1567 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1568 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1569 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1570 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1572 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1574 btrfs_mark_buffer_dirty(leaf);
1578 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1579 struct btrfs_root *root,
1580 struct btrfs_path *path,
1581 struct btrfs_extent_inline_ref **ref_ret,
1582 u64 bytenr, u64 num_bytes, u64 parent,
1583 u64 root_objectid, u64 owner, u64 offset)
1587 ret = lookup_inline_extent_backref(trans, root, path, ref_ret,
1588 bytenr, num_bytes, parent,
1589 root_objectid, owner, offset, 0);
1593 btrfs_release_path(root, path);
1596 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1597 ret = lookup_tree_block_ref(trans, root, path, bytenr, parent,
1600 ret = lookup_extent_data_ref(trans, root, path, bytenr, parent,
1601 root_objectid, owner, offset);
1607 * helper to update/remove inline back ref
1609 static noinline_for_stack
1610 int update_inline_extent_backref(struct btrfs_trans_handle *trans,
1611 struct btrfs_root *root,
1612 struct btrfs_path *path,
1613 struct btrfs_extent_inline_ref *iref,
1615 struct btrfs_delayed_extent_op *extent_op)
1617 struct extent_buffer *leaf;
1618 struct btrfs_extent_item *ei;
1619 struct btrfs_extent_data_ref *dref = NULL;
1620 struct btrfs_shared_data_ref *sref = NULL;
1629 leaf = path->nodes[0];
1630 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1631 refs = btrfs_extent_refs(leaf, ei);
1632 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1633 refs += refs_to_mod;
1634 btrfs_set_extent_refs(leaf, ei, refs);
1636 __run_delayed_extent_op(extent_op, leaf, ei);
1638 type = btrfs_extent_inline_ref_type(leaf, iref);
1640 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1641 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1642 refs = btrfs_extent_data_ref_count(leaf, dref);
1643 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1644 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1645 refs = btrfs_shared_data_ref_count(leaf, sref);
1648 BUG_ON(refs_to_mod != -1);
1651 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1652 refs += refs_to_mod;
1655 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1656 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1658 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1660 size = btrfs_extent_inline_ref_size(type);
1661 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1662 ptr = (unsigned long)iref;
1663 end = (unsigned long)ei + item_size;
1664 if (ptr + size < end)
1665 memmove_extent_buffer(leaf, ptr, ptr + size,
1668 ret = btrfs_truncate_item(trans, root, path, item_size, 1);
1671 btrfs_mark_buffer_dirty(leaf);
1675 static noinline_for_stack
1676 int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1677 struct btrfs_root *root,
1678 struct btrfs_path *path,
1679 u64 bytenr, u64 num_bytes, u64 parent,
1680 u64 root_objectid, u64 owner,
1681 u64 offset, int refs_to_add,
1682 struct btrfs_delayed_extent_op *extent_op)
1684 struct btrfs_extent_inline_ref *iref;
1687 ret = lookup_inline_extent_backref(trans, root, path, &iref,
1688 bytenr, num_bytes, parent,
1689 root_objectid, owner, offset, 1);
1691 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
1692 ret = update_inline_extent_backref(trans, root, path, iref,
1693 refs_to_add, extent_op);
1694 } else if (ret == -ENOENT) {
1695 ret = setup_inline_extent_backref(trans, root, path, iref,
1696 parent, root_objectid,
1697 owner, offset, refs_to_add,
1703 static int insert_extent_backref(struct btrfs_trans_handle *trans,
1704 struct btrfs_root *root,
1705 struct btrfs_path *path,
1706 u64 bytenr, u64 parent, u64 root_objectid,
1707 u64 owner, u64 offset, int refs_to_add)
1710 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1711 BUG_ON(refs_to_add != 1);
1712 ret = insert_tree_block_ref(trans, root, path, bytenr,
1713 parent, root_objectid);
1715 ret = insert_extent_data_ref(trans, root, path, bytenr,
1716 parent, root_objectid,
1717 owner, offset, refs_to_add);
1722 static int remove_extent_backref(struct btrfs_trans_handle *trans,
1723 struct btrfs_root *root,
1724 struct btrfs_path *path,
1725 struct btrfs_extent_inline_ref *iref,
1726 int refs_to_drop, int is_data)
1730 BUG_ON(!is_data && refs_to_drop != 1);
1732 ret = update_inline_extent_backref(trans, root, path, iref,
1733 -refs_to_drop, NULL);
1734 } else if (is_data) {
1735 ret = remove_extent_data_ref(trans, root, path, refs_to_drop);
1737 ret = btrfs_del_item(trans, root, path);
1742 static void btrfs_issue_discard(struct block_device *bdev,
1745 blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_KERNEL,
1746 BLKDEV_IFL_WAIT | BLKDEV_IFL_BARRIER);
1749 static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
1753 u64 map_length = num_bytes;
1754 struct btrfs_multi_bio *multi = NULL;
1756 if (!btrfs_test_opt(root, DISCARD))
1759 /* Tell the block device(s) that the sectors can be discarded */
1760 ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
1761 bytenr, &map_length, &multi, 0);
1763 struct btrfs_bio_stripe *stripe = multi->stripes;
1766 if (map_length > num_bytes)
1767 map_length = num_bytes;
1769 for (i = 0; i < multi->num_stripes; i++, stripe++) {
1770 btrfs_issue_discard(stripe->dev->bdev,
1780 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1781 struct btrfs_root *root,
1782 u64 bytenr, u64 num_bytes, u64 parent,
1783 u64 root_objectid, u64 owner, u64 offset)
1786 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID &&
1787 root_objectid == BTRFS_TREE_LOG_OBJECTID);
1789 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1790 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
1791 parent, root_objectid, (int)owner,
1792 BTRFS_ADD_DELAYED_REF, NULL);
1794 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
1795 parent, root_objectid, owner, offset,
1796 BTRFS_ADD_DELAYED_REF, NULL);
1801 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1802 struct btrfs_root *root,
1803 u64 bytenr, u64 num_bytes,
1804 u64 parent, u64 root_objectid,
1805 u64 owner, u64 offset, int refs_to_add,
1806 struct btrfs_delayed_extent_op *extent_op)
1808 struct btrfs_path *path;
1809 struct extent_buffer *leaf;
1810 struct btrfs_extent_item *item;
1815 path = btrfs_alloc_path();
1820 path->leave_spinning = 1;
1821 /* this will setup the path even if it fails to insert the back ref */
1822 ret = insert_inline_extent_backref(trans, root->fs_info->extent_root,
1823 path, bytenr, num_bytes, parent,
1824 root_objectid, owner, offset,
1825 refs_to_add, extent_op);
1829 if (ret != -EAGAIN) {
1834 leaf = path->nodes[0];
1835 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1836 refs = btrfs_extent_refs(leaf, item);
1837 btrfs_set_extent_refs(leaf, item, refs + refs_to_add);
1839 __run_delayed_extent_op(extent_op, leaf, item);
1841 btrfs_mark_buffer_dirty(leaf);
1842 btrfs_release_path(root->fs_info->extent_root, path);
1845 path->leave_spinning = 1;
1847 /* now insert the actual backref */
1848 ret = insert_extent_backref(trans, root->fs_info->extent_root,
1849 path, bytenr, parent, root_objectid,
1850 owner, offset, refs_to_add);
1853 btrfs_free_path(path);
1857 static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
1858 struct btrfs_root *root,
1859 struct btrfs_delayed_ref_node *node,
1860 struct btrfs_delayed_extent_op *extent_op,
1861 int insert_reserved)
1864 struct btrfs_delayed_data_ref *ref;
1865 struct btrfs_key ins;
1870 ins.objectid = node->bytenr;
1871 ins.offset = node->num_bytes;
1872 ins.type = BTRFS_EXTENT_ITEM_KEY;
1874 ref = btrfs_delayed_node_to_data_ref(node);
1875 if (node->type == BTRFS_SHARED_DATA_REF_KEY)
1876 parent = ref->parent;
1878 ref_root = ref->root;
1880 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
1882 BUG_ON(extent_op->update_key);
1883 flags |= extent_op->flags_to_set;
1885 ret = alloc_reserved_file_extent(trans, root,
1886 parent, ref_root, flags,
1887 ref->objectid, ref->offset,
1888 &ins, node->ref_mod);
1889 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
1890 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
1891 node->num_bytes, parent,
1892 ref_root, ref->objectid,
1893 ref->offset, node->ref_mod,
1895 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
1896 ret = __btrfs_free_extent(trans, root, node->bytenr,
1897 node->num_bytes, parent,
1898 ref_root, ref->objectid,
1899 ref->offset, node->ref_mod,
1907 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
1908 struct extent_buffer *leaf,
1909 struct btrfs_extent_item *ei)
1911 u64 flags = btrfs_extent_flags(leaf, ei);
1912 if (extent_op->update_flags) {
1913 flags |= extent_op->flags_to_set;
1914 btrfs_set_extent_flags(leaf, ei, flags);
1917 if (extent_op->update_key) {
1918 struct btrfs_tree_block_info *bi;
1919 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK));
1920 bi = (struct btrfs_tree_block_info *)(ei + 1);
1921 btrfs_set_tree_block_key(leaf, bi, &extent_op->key);
1925 static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
1926 struct btrfs_root *root,
1927 struct btrfs_delayed_ref_node *node,
1928 struct btrfs_delayed_extent_op *extent_op)
1930 struct btrfs_key key;
1931 struct btrfs_path *path;
1932 struct btrfs_extent_item *ei;
1933 struct extent_buffer *leaf;
1938 path = btrfs_alloc_path();
1942 key.objectid = node->bytenr;
1943 key.type = BTRFS_EXTENT_ITEM_KEY;
1944 key.offset = node->num_bytes;
1947 path->leave_spinning = 1;
1948 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key,
1959 leaf = path->nodes[0];
1960 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1961 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1962 if (item_size < sizeof(*ei)) {
1963 ret = convert_extent_item_v0(trans, root->fs_info->extent_root,
1969 leaf = path->nodes[0];
1970 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1973 BUG_ON(item_size < sizeof(*ei));
1974 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1975 __run_delayed_extent_op(extent_op, leaf, ei);
1977 btrfs_mark_buffer_dirty(leaf);
1979 btrfs_free_path(path);
1983 static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
1984 struct btrfs_root *root,
1985 struct btrfs_delayed_ref_node *node,
1986 struct btrfs_delayed_extent_op *extent_op,
1987 int insert_reserved)
1990 struct btrfs_delayed_tree_ref *ref;
1991 struct btrfs_key ins;
1995 ins.objectid = node->bytenr;
1996 ins.offset = node->num_bytes;
1997 ins.type = BTRFS_EXTENT_ITEM_KEY;
1999 ref = btrfs_delayed_node_to_tree_ref(node);
2000 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2001 parent = ref->parent;
2003 ref_root = ref->root;
2005 BUG_ON(node->ref_mod != 1);
2006 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
2007 BUG_ON(!extent_op || !extent_op->update_flags ||
2008 !extent_op->update_key);
2009 ret = alloc_reserved_tree_block(trans, root,
2011 extent_op->flags_to_set,
2014 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
2015 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
2016 node->num_bytes, parent, ref_root,
2017 ref->level, 0, 1, extent_op);
2018 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
2019 ret = __btrfs_free_extent(trans, root, node->bytenr,
2020 node->num_bytes, parent, ref_root,
2021 ref->level, 0, 1, extent_op);
2028 /* helper function to actually process a single delayed ref entry */
2029 static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
2030 struct btrfs_root *root,
2031 struct btrfs_delayed_ref_node *node,
2032 struct btrfs_delayed_extent_op *extent_op,
2033 int insert_reserved)
2036 if (btrfs_delayed_ref_is_head(node)) {
2037 struct btrfs_delayed_ref_head *head;
2039 * we've hit the end of the chain and we were supposed
2040 * to insert this extent into the tree. But, it got
2041 * deleted before we ever needed to insert it, so all
2042 * we have to do is clean up the accounting
2045 head = btrfs_delayed_node_to_head(node);
2046 if (insert_reserved) {
2047 btrfs_pin_extent(root, node->bytenr,
2048 node->num_bytes, 1);
2049 if (head->is_data) {
2050 ret = btrfs_del_csums(trans, root,
2056 mutex_unlock(&head->mutex);
2060 if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
2061 node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2062 ret = run_delayed_tree_ref(trans, root, node, extent_op,
2064 else if (node->type == BTRFS_EXTENT_DATA_REF_KEY ||
2065 node->type == BTRFS_SHARED_DATA_REF_KEY)
2066 ret = run_delayed_data_ref(trans, root, node, extent_op,
2073 static noinline struct btrfs_delayed_ref_node *
2074 select_delayed_ref(struct btrfs_delayed_ref_head *head)
2076 struct rb_node *node;
2077 struct btrfs_delayed_ref_node *ref;
2078 int action = BTRFS_ADD_DELAYED_REF;
2081 * select delayed ref of type BTRFS_ADD_DELAYED_REF first.
2082 * this prevents ref count from going down to zero when
2083 * there still are pending delayed ref.
2085 node = rb_prev(&head->node.rb_node);
2089 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2091 if (ref->bytenr != head->node.bytenr)
2093 if (ref->action == action)
2095 node = rb_prev(node);
2097 if (action == BTRFS_ADD_DELAYED_REF) {
2098 action = BTRFS_DROP_DELAYED_REF;
2104 static noinline int run_clustered_refs(struct btrfs_trans_handle *trans,
2105 struct btrfs_root *root,
2106 struct list_head *cluster)
2108 struct btrfs_delayed_ref_root *delayed_refs;
2109 struct btrfs_delayed_ref_node *ref;
2110 struct btrfs_delayed_ref_head *locked_ref = NULL;
2111 struct btrfs_delayed_extent_op *extent_op;
2114 int must_insert_reserved = 0;
2116 delayed_refs = &trans->transaction->delayed_refs;
2119 /* pick a new head ref from the cluster list */
2120 if (list_empty(cluster))
2123 locked_ref = list_entry(cluster->next,
2124 struct btrfs_delayed_ref_head, cluster);
2126 /* grab the lock that says we are going to process
2127 * all the refs for this head */
2128 ret = btrfs_delayed_ref_lock(trans, locked_ref);
2131 * we may have dropped the spin lock to get the head
2132 * mutex lock, and that might have given someone else
2133 * time to free the head. If that's true, it has been
2134 * removed from our list and we can move on.
2136 if (ret == -EAGAIN) {
2144 * record the must insert reserved flag before we
2145 * drop the spin lock.
2147 must_insert_reserved = locked_ref->must_insert_reserved;
2148 locked_ref->must_insert_reserved = 0;
2150 extent_op = locked_ref->extent_op;
2151 locked_ref->extent_op = NULL;
2154 * locked_ref is the head node, so we have to go one
2155 * node back for any delayed ref updates
2157 ref = select_delayed_ref(locked_ref);
2159 /* All delayed refs have been processed, Go ahead
2160 * and send the head node to run_one_delayed_ref,
2161 * so that any accounting fixes can happen
2163 ref = &locked_ref->node;
2165 if (extent_op && must_insert_reserved) {
2171 spin_unlock(&delayed_refs->lock);
2173 ret = run_delayed_extent_op(trans, root,
2179 spin_lock(&delayed_refs->lock);
2183 list_del_init(&locked_ref->cluster);
2188 rb_erase(&ref->rb_node, &delayed_refs->root);
2189 delayed_refs->num_entries--;
2191 spin_unlock(&delayed_refs->lock);
2193 ret = run_one_delayed_ref(trans, root, ref, extent_op,
2194 must_insert_reserved);
2197 btrfs_put_delayed_ref(ref);
2202 spin_lock(&delayed_refs->lock);
2208 * this starts processing the delayed reference count updates and
2209 * extent insertions we have queued up so far. count can be
2210 * 0, which means to process everything in the tree at the start
2211 * of the run (but not newly added entries), or it can be some target
2212 * number you'd like to process.
2214 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2215 struct btrfs_root *root, unsigned long count)
2217 struct rb_node *node;
2218 struct btrfs_delayed_ref_root *delayed_refs;
2219 struct btrfs_delayed_ref_node *ref;
2220 struct list_head cluster;
2222 int run_all = count == (unsigned long)-1;
2225 if (root == root->fs_info->extent_root)
2226 root = root->fs_info->tree_root;
2228 delayed_refs = &trans->transaction->delayed_refs;
2229 INIT_LIST_HEAD(&cluster);
2231 spin_lock(&delayed_refs->lock);
2233 count = delayed_refs->num_entries * 2;
2237 if (!(run_all || run_most) &&
2238 delayed_refs->num_heads_ready < 64)
2242 * go find something we can process in the rbtree. We start at
2243 * the beginning of the tree, and then build a cluster
2244 * of refs to process starting at the first one we are able to
2247 ret = btrfs_find_ref_cluster(trans, &cluster,
2248 delayed_refs->run_delayed_start);
2252 ret = run_clustered_refs(trans, root, &cluster);
2255 count -= min_t(unsigned long, ret, count);
2262 node = rb_first(&delayed_refs->root);
2265 count = (unsigned long)-1;
2268 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2270 if (btrfs_delayed_ref_is_head(ref)) {
2271 struct btrfs_delayed_ref_head *head;
2273 head = btrfs_delayed_node_to_head(ref);
2274 atomic_inc(&ref->refs);
2276 spin_unlock(&delayed_refs->lock);
2277 mutex_lock(&head->mutex);
2278 mutex_unlock(&head->mutex);
2280 btrfs_put_delayed_ref(ref);
2284 node = rb_next(node);
2286 spin_unlock(&delayed_refs->lock);
2287 schedule_timeout(1);
2291 spin_unlock(&delayed_refs->lock);
2295 int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
2296 struct btrfs_root *root,
2297 u64 bytenr, u64 num_bytes, u64 flags,
2300 struct btrfs_delayed_extent_op *extent_op;
2303 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
2307 extent_op->flags_to_set = flags;
2308 extent_op->update_flags = 1;
2309 extent_op->update_key = 0;
2310 extent_op->is_data = is_data ? 1 : 0;
2312 ret = btrfs_add_delayed_extent_op(trans, bytenr, num_bytes, extent_op);
2318 static noinline int check_delayed_ref(struct btrfs_trans_handle *trans,
2319 struct btrfs_root *root,
2320 struct btrfs_path *path,
2321 u64 objectid, u64 offset, u64 bytenr)
2323 struct btrfs_delayed_ref_head *head;
2324 struct btrfs_delayed_ref_node *ref;
2325 struct btrfs_delayed_data_ref *data_ref;
2326 struct btrfs_delayed_ref_root *delayed_refs;
2327 struct rb_node *node;
2331 delayed_refs = &trans->transaction->delayed_refs;
2332 spin_lock(&delayed_refs->lock);
2333 head = btrfs_find_delayed_ref_head(trans, bytenr);
2337 if (!mutex_trylock(&head->mutex)) {
2338 atomic_inc(&head->node.refs);
2339 spin_unlock(&delayed_refs->lock);
2341 btrfs_release_path(root->fs_info->extent_root, path);
2343 mutex_lock(&head->mutex);
2344 mutex_unlock(&head->mutex);
2345 btrfs_put_delayed_ref(&head->node);
2349 node = rb_prev(&head->node.rb_node);
2353 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2355 if (ref->bytenr != bytenr)
2359 if (ref->type != BTRFS_EXTENT_DATA_REF_KEY)
2362 data_ref = btrfs_delayed_node_to_data_ref(ref);
2364 node = rb_prev(node);
2366 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2367 if (ref->bytenr == bytenr)
2371 if (data_ref->root != root->root_key.objectid ||
2372 data_ref->objectid != objectid || data_ref->offset != offset)
2377 mutex_unlock(&head->mutex);
2379 spin_unlock(&delayed_refs->lock);
2383 static noinline int check_committed_ref(struct btrfs_trans_handle *trans,
2384 struct btrfs_root *root,
2385 struct btrfs_path *path,
2386 u64 objectid, u64 offset, u64 bytenr)
2388 struct btrfs_root *extent_root = root->fs_info->extent_root;
2389 struct extent_buffer *leaf;
2390 struct btrfs_extent_data_ref *ref;
2391 struct btrfs_extent_inline_ref *iref;
2392 struct btrfs_extent_item *ei;
2393 struct btrfs_key key;
2397 key.objectid = bytenr;
2398 key.offset = (u64)-1;
2399 key.type = BTRFS_EXTENT_ITEM_KEY;
2401 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
2407 if (path->slots[0] == 0)
2411 leaf = path->nodes[0];
2412 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2414 if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY)
2418 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2419 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2420 if (item_size < sizeof(*ei)) {
2421 WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0));
2425 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2427 if (item_size != sizeof(*ei) +
2428 btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY))
2431 if (btrfs_extent_generation(leaf, ei) <=
2432 btrfs_root_last_snapshot(&root->root_item))
2435 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
2436 if (btrfs_extent_inline_ref_type(leaf, iref) !=
2437 BTRFS_EXTENT_DATA_REF_KEY)
2440 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
2441 if (btrfs_extent_refs(leaf, ei) !=
2442 btrfs_extent_data_ref_count(leaf, ref) ||
2443 btrfs_extent_data_ref_root(leaf, ref) !=
2444 root->root_key.objectid ||
2445 btrfs_extent_data_ref_objectid(leaf, ref) != objectid ||
2446 btrfs_extent_data_ref_offset(leaf, ref) != offset)
2454 int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans,
2455 struct btrfs_root *root,
2456 u64 objectid, u64 offset, u64 bytenr)
2458 struct btrfs_path *path;
2462 path = btrfs_alloc_path();
2467 ret = check_committed_ref(trans, root, path, objectid,
2469 if (ret && ret != -ENOENT)
2472 ret2 = check_delayed_ref(trans, root, path, objectid,
2474 } while (ret2 == -EAGAIN);
2476 if (ret2 && ret2 != -ENOENT) {
2481 if (ret != -ENOENT || ret2 != -ENOENT)
2484 btrfs_free_path(path);
2485 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
2491 int btrfs_cache_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2492 struct extent_buffer *buf, u32 nr_extents)
2494 struct btrfs_key key;
2495 struct btrfs_file_extent_item *fi;
2503 if (!root->ref_cows)
2506 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
2508 root_gen = root->root_key.offset;
2511 root_gen = trans->transid - 1;
2514 level = btrfs_header_level(buf);
2515 nritems = btrfs_header_nritems(buf);
2518 struct btrfs_leaf_ref *ref;
2519 struct btrfs_extent_info *info;
2521 ref = btrfs_alloc_leaf_ref(root, nr_extents);
2527 ref->root_gen = root_gen;
2528 ref->bytenr = buf->start;
2529 ref->owner = btrfs_header_owner(buf);
2530 ref->generation = btrfs_header_generation(buf);
2531 ref->nritems = nr_extents;
2532 info = ref->extents;
2534 for (i = 0; nr_extents > 0 && i < nritems; i++) {
2536 btrfs_item_key_to_cpu(buf, &key, i);
2537 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2539 fi = btrfs_item_ptr(buf, i,
2540 struct btrfs_file_extent_item);
2541 if (btrfs_file_extent_type(buf, fi) ==
2542 BTRFS_FILE_EXTENT_INLINE)
2544 disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2545 if (disk_bytenr == 0)
2548 info->bytenr = disk_bytenr;
2550 btrfs_file_extent_disk_num_bytes(buf, fi);
2551 info->objectid = key.objectid;
2552 info->offset = key.offset;
2556 ret = btrfs_add_leaf_ref(root, ref, shared);
2557 if (ret == -EEXIST && shared) {
2558 struct btrfs_leaf_ref *old;
2559 old = btrfs_lookup_leaf_ref(root, ref->bytenr);
2561 btrfs_remove_leaf_ref(root, old);
2562 btrfs_free_leaf_ref(root, old);
2563 ret = btrfs_add_leaf_ref(root, ref, shared);
2566 btrfs_free_leaf_ref(root, ref);
2572 /* when a block goes through cow, we update the reference counts of
2573 * everything that block points to. The internal pointers of the block
2574 * can be in just about any order, and it is likely to have clusters of
2575 * things that are close together and clusters of things that are not.
2577 * To help reduce the seeks that come with updating all of these reference
2578 * counts, sort them by byte number before actual updates are done.
2580 * struct refsort is used to match byte number to slot in the btree block.
2581 * we sort based on the byte number and then use the slot to actually
2584 * struct refsort is smaller than strcut btrfs_item and smaller than
2585 * struct btrfs_key_ptr. Since we're currently limited to the page size
2586 * for a btree block, there's no way for a kmalloc of refsorts for a
2587 * single node to be bigger than a page.
2595 * for passing into sort()
2597 static int refsort_cmp(const void *a_void, const void *b_void)
2599 const struct refsort *a = a_void;
2600 const struct refsort *b = b_void;
2602 if (a->bytenr < b->bytenr)
2604 if (a->bytenr > b->bytenr)
2610 static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
2611 struct btrfs_root *root,
2612 struct extent_buffer *buf,
2613 int full_backref, int inc)
2620 struct btrfs_key key;
2621 struct btrfs_file_extent_item *fi;
2625 int (*process_func)(struct btrfs_trans_handle *, struct btrfs_root *,
2626 u64, u64, u64, u64, u64, u64);
2628 ref_root = btrfs_header_owner(buf);
2629 nritems = btrfs_header_nritems(buf);
2630 level = btrfs_header_level(buf);
2632 if (!root->ref_cows && level == 0)
2636 process_func = btrfs_inc_extent_ref;
2638 process_func = btrfs_free_extent;
2641 parent = buf->start;
2645 for (i = 0; i < nritems; i++) {
2647 btrfs_item_key_to_cpu(buf, &key, i);
2648 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2650 fi = btrfs_item_ptr(buf, i,
2651 struct btrfs_file_extent_item);
2652 if (btrfs_file_extent_type(buf, fi) ==
2653 BTRFS_FILE_EXTENT_INLINE)
2655 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2659 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
2660 key.offset -= btrfs_file_extent_offset(buf, fi);
2661 ret = process_func(trans, root, bytenr, num_bytes,
2662 parent, ref_root, key.objectid,
2667 bytenr = btrfs_node_blockptr(buf, i);
2668 num_bytes = btrfs_level_size(root, level - 1);
2669 ret = process_func(trans, root, bytenr, num_bytes,
2670 parent, ref_root, level - 1, 0);
2681 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2682 struct extent_buffer *buf, int full_backref)
2684 return __btrfs_mod_ref(trans, root, buf, full_backref, 1);
2687 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2688 struct extent_buffer *buf, int full_backref)
2690 return __btrfs_mod_ref(trans, root, buf, full_backref, 0);
2693 static int write_one_cache_group(struct btrfs_trans_handle *trans,
2694 struct btrfs_root *root,
2695 struct btrfs_path *path,
2696 struct btrfs_block_group_cache *cache)
2699 struct btrfs_root *extent_root = root->fs_info->extent_root;
2701 struct extent_buffer *leaf;
2703 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
2708 leaf = path->nodes[0];
2709 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
2710 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
2711 btrfs_mark_buffer_dirty(leaf);
2712 btrfs_release_path(extent_root, path);
2720 static struct btrfs_block_group_cache *
2721 next_block_group(struct btrfs_root *root,
2722 struct btrfs_block_group_cache *cache)
2724 struct rb_node *node;
2725 spin_lock(&root->fs_info->block_group_cache_lock);
2726 node = rb_next(&cache->cache_node);
2727 btrfs_put_block_group(cache);
2729 cache = rb_entry(node, struct btrfs_block_group_cache,
2731 btrfs_get_block_group(cache);
2734 spin_unlock(&root->fs_info->block_group_cache_lock);
2738 static int cache_save_setup(struct btrfs_block_group_cache *block_group,
2739 struct btrfs_trans_handle *trans,
2740 struct btrfs_path *path)
2742 struct btrfs_root *root = block_group->fs_info->tree_root;
2743 struct inode *inode = NULL;
2750 * If this block group is smaller than 100 megs don't bother caching the
2753 if (block_group->key.offset < (100 * 1024 * 1024)) {
2754 spin_lock(&block_group->lock);
2755 block_group->disk_cache_state = BTRFS_DC_WRITTEN;
2756 spin_unlock(&block_group->lock);
2761 inode = lookup_free_space_inode(root, block_group, path);
2762 if (IS_ERR(inode) && PTR_ERR(inode) != -ENOENT) {
2763 ret = PTR_ERR(inode);
2764 btrfs_release_path(root, path);
2768 if (IS_ERR(inode)) {
2772 if (block_group->ro)
2775 ret = create_free_space_inode(root, trans, block_group, path);
2782 * We want to set the generation to 0, that way if anything goes wrong
2783 * from here on out we know not to trust this cache when we load up next
2786 BTRFS_I(inode)->generation = 0;
2787 ret = btrfs_update_inode(trans, root, inode);
2790 if (i_size_read(inode) > 0) {
2791 ret = btrfs_truncate_free_space_cache(root, trans, path,
2797 spin_lock(&block_group->lock);
2798 if (block_group->cached != BTRFS_CACHE_FINISHED) {
2799 spin_unlock(&block_group->lock);
2802 spin_unlock(&block_group->lock);
2804 num_pages = (int)div64_u64(block_group->key.offset, 1024 * 1024 * 1024);
2809 * Just to make absolutely sure we have enough space, we're going to
2810 * preallocate 12 pages worth of space for each block group. In
2811 * practice we ought to use at most 8, but we need extra space so we can
2812 * add our header and have a terminator between the extents and the
2816 num_pages *= PAGE_CACHE_SIZE;
2818 ret = btrfs_check_data_free_space(inode, num_pages);
2822 ret = btrfs_prealloc_file_range_trans(inode, trans, 0, 0, num_pages,
2823 num_pages, num_pages,
2825 btrfs_free_reserved_data_space(inode, num_pages);
2829 btrfs_release_path(root, path);
2831 spin_lock(&block_group->lock);
2833 block_group->disk_cache_state = BTRFS_DC_ERROR;
2835 block_group->disk_cache_state = BTRFS_DC_SETUP;
2836 spin_unlock(&block_group->lock);
2841 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
2842 struct btrfs_root *root)
2844 struct btrfs_block_group_cache *cache;
2846 struct btrfs_path *path;
2849 path = btrfs_alloc_path();
2855 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2857 if (cache->disk_cache_state == BTRFS_DC_CLEAR)
2859 cache = next_block_group(root, cache);
2867 err = cache_save_setup(cache, trans, path);
2868 last = cache->key.objectid + cache->key.offset;
2869 btrfs_put_block_group(cache);
2874 err = btrfs_run_delayed_refs(trans, root,
2879 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2881 if (cache->disk_cache_state == BTRFS_DC_CLEAR) {
2882 btrfs_put_block_group(cache);
2888 cache = next_block_group(root, cache);
2897 if (cache->disk_cache_state == BTRFS_DC_SETUP)
2898 cache->disk_cache_state = BTRFS_DC_NEED_WRITE;
2900 last = cache->key.objectid + cache->key.offset;
2902 err = write_one_cache_group(trans, root, path, cache);
2904 btrfs_put_block_group(cache);
2909 * I don't think this is needed since we're just marking our
2910 * preallocated extent as written, but just in case it can't
2914 err = btrfs_run_delayed_refs(trans, root,
2919 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2922 * Really this shouldn't happen, but it could if we
2923 * couldn't write the entire preallocated extent and
2924 * splitting the extent resulted in a new block.
2927 btrfs_put_block_group(cache);
2930 if (cache->disk_cache_state == BTRFS_DC_NEED_WRITE)
2932 cache = next_block_group(root, cache);
2941 btrfs_write_out_cache(root, trans, cache, path);
2944 * If we didn't have an error then the cache state is still
2945 * NEED_WRITE, so we can set it to WRITTEN.
2947 if (cache->disk_cache_state == BTRFS_DC_NEED_WRITE)
2948 cache->disk_cache_state = BTRFS_DC_WRITTEN;
2949 last = cache->key.objectid + cache->key.offset;
2950 btrfs_put_block_group(cache);
2953 btrfs_free_path(path);
2957 int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr)
2959 struct btrfs_block_group_cache *block_group;
2962 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
2963 if (!block_group || block_group->ro)
2966 btrfs_put_block_group(block_group);
2970 static int update_space_info(struct btrfs_fs_info *info, u64 flags,
2971 u64 total_bytes, u64 bytes_used,
2972 struct btrfs_space_info **space_info)
2974 struct btrfs_space_info *found;
2978 if (flags & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
2979 BTRFS_BLOCK_GROUP_RAID10))
2984 found = __find_space_info(info, flags);
2986 spin_lock(&found->lock);
2987 found->total_bytes += total_bytes;
2988 found->disk_total += total_bytes * factor;
2989 found->bytes_used += bytes_used;
2990 found->disk_used += bytes_used * factor;
2992 spin_unlock(&found->lock);
2993 *space_info = found;
2996 found = kzalloc(sizeof(*found), GFP_NOFS);
3000 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
3001 INIT_LIST_HEAD(&found->block_groups[i]);
3002 init_rwsem(&found->groups_sem);
3003 spin_lock_init(&found->lock);
3004 found->flags = flags & (BTRFS_BLOCK_GROUP_DATA |
3005 BTRFS_BLOCK_GROUP_SYSTEM |
3006 BTRFS_BLOCK_GROUP_METADATA);
3007 found->total_bytes = total_bytes;
3008 found->disk_total = total_bytes * factor;
3009 found->bytes_used = bytes_used;
3010 found->disk_used = bytes_used * factor;
3011 found->bytes_pinned = 0;
3012 found->bytes_reserved = 0;
3013 found->bytes_readonly = 0;
3014 found->bytes_may_use = 0;
3016 found->force_alloc = 0;
3017 *space_info = found;
3018 list_add_rcu(&found->list, &info->space_info);
3019 atomic_set(&found->caching_threads, 0);
3023 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
3025 u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 |
3026 BTRFS_BLOCK_GROUP_RAID1 |
3027 BTRFS_BLOCK_GROUP_RAID10 |
3028 BTRFS_BLOCK_GROUP_DUP);
3030 if (flags & BTRFS_BLOCK_GROUP_DATA)
3031 fs_info->avail_data_alloc_bits |= extra_flags;
3032 if (flags & BTRFS_BLOCK_GROUP_METADATA)
3033 fs_info->avail_metadata_alloc_bits |= extra_flags;
3034 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
3035 fs_info->avail_system_alloc_bits |= extra_flags;
3039 u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
3041 u64 num_devices = root->fs_info->fs_devices->rw_devices;
3043 if (num_devices == 1)
3044 flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0);
3045 if (num_devices < 4)
3046 flags &= ~BTRFS_BLOCK_GROUP_RAID10;
3048 if ((flags & BTRFS_BLOCK_GROUP_DUP) &&
3049 (flags & (BTRFS_BLOCK_GROUP_RAID1 |
3050 BTRFS_BLOCK_GROUP_RAID10))) {
3051 flags &= ~BTRFS_BLOCK_GROUP_DUP;
3054 if ((flags & BTRFS_BLOCK_GROUP_RAID1) &&
3055 (flags & BTRFS_BLOCK_GROUP_RAID10)) {
3056 flags &= ~BTRFS_BLOCK_GROUP_RAID1;
3059 if ((flags & BTRFS_BLOCK_GROUP_RAID0) &&
3060 ((flags & BTRFS_BLOCK_GROUP_RAID1) |
3061 (flags & BTRFS_BLOCK_GROUP_RAID10) |
3062 (flags & BTRFS_BLOCK_GROUP_DUP)))
3063 flags &= ~BTRFS_BLOCK_GROUP_RAID0;
3067 static u64 get_alloc_profile(struct btrfs_root *root, u64 flags)
3069 if (flags & BTRFS_BLOCK_GROUP_DATA)
3070 flags |= root->fs_info->avail_data_alloc_bits &
3071 root->fs_info->data_alloc_profile;
3072 else if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
3073 flags |= root->fs_info->avail_system_alloc_bits &
3074 root->fs_info->system_alloc_profile;
3075 else if (flags & BTRFS_BLOCK_GROUP_METADATA)
3076 flags |= root->fs_info->avail_metadata_alloc_bits &
3077 root->fs_info->metadata_alloc_profile;
3078 return btrfs_reduce_alloc_profile(root, flags);
3081 static u64 btrfs_get_alloc_profile(struct btrfs_root *root, int data)
3086 flags = BTRFS_BLOCK_GROUP_DATA;
3087 else if (root == root->fs_info->chunk_root)
3088 flags = BTRFS_BLOCK_GROUP_SYSTEM;
3090 flags = BTRFS_BLOCK_GROUP_METADATA;
3092 return get_alloc_profile(root, flags);
3095 void btrfs_set_inode_space_info(struct btrfs_root *root, struct inode *inode)
3097 BTRFS_I(inode)->space_info = __find_space_info(root->fs_info,
3098 BTRFS_BLOCK_GROUP_DATA);
3102 * This will check the space that the inode allocates from to make sure we have
3103 * enough space for bytes.
3105 int btrfs_check_data_free_space(struct inode *inode, u64 bytes)
3107 struct btrfs_space_info *data_sinfo;
3108 struct btrfs_root *root = BTRFS_I(inode)->root;
3110 int ret = 0, committed = 0, alloc_chunk = 1;
3112 /* make sure bytes are sectorsize aligned */
3113 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3115 if (root == root->fs_info->tree_root) {
3120 data_sinfo = BTRFS_I(inode)->space_info;
3125 /* make sure we have enough space to handle the data first */
3126 spin_lock(&data_sinfo->lock);
3127 used = data_sinfo->bytes_used + data_sinfo->bytes_reserved +
3128 data_sinfo->bytes_pinned + data_sinfo->bytes_readonly +
3129 data_sinfo->bytes_may_use;
3131 if (used + bytes > data_sinfo->total_bytes) {
3132 struct btrfs_trans_handle *trans;
3135 * if we don't have enough free bytes in this space then we need
3136 * to alloc a new chunk.
3138 if (!data_sinfo->full && alloc_chunk) {
3141 data_sinfo->force_alloc = 1;
3142 spin_unlock(&data_sinfo->lock);
3144 alloc_target = btrfs_get_alloc_profile(root, 1);
3145 trans = btrfs_join_transaction(root, 1);
3147 return PTR_ERR(trans);
3149 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
3150 bytes + 2 * 1024 * 1024,
3152 btrfs_end_transaction(trans, root);
3157 btrfs_set_inode_space_info(root, inode);
3158 data_sinfo = BTRFS_I(inode)->space_info;
3162 spin_unlock(&data_sinfo->lock);
3164 /* commit the current transaction and try again */
3165 if (!committed && !root->fs_info->open_ioctl_trans) {
3167 trans = btrfs_join_transaction(root, 1);
3169 return PTR_ERR(trans);
3170 ret = btrfs_commit_transaction(trans, root);
3176 #if 0 /* I hope we never need this code again, just in case */
3177 printk(KERN_ERR "no space left, need %llu, %llu bytes_used, "
3178 "%llu bytes_reserved, " "%llu bytes_pinned, "
3179 "%llu bytes_readonly, %llu may use %llu total\n",
3180 (unsigned long long)bytes,
3181 (unsigned long long)data_sinfo->bytes_used,
3182 (unsigned long long)data_sinfo->bytes_reserved,
3183 (unsigned long long)data_sinfo->bytes_pinned,
3184 (unsigned long long)data_sinfo->bytes_readonly,
3185 (unsigned long long)data_sinfo->bytes_may_use,
3186 (unsigned long long)data_sinfo->total_bytes);
3190 data_sinfo->bytes_may_use += bytes;
3191 BTRFS_I(inode)->reserved_bytes += bytes;
3192 spin_unlock(&data_sinfo->lock);
3198 * called when we are clearing an delalloc extent from the
3199 * inode's io_tree or there was an error for whatever reason
3200 * after calling btrfs_check_data_free_space
3202 void btrfs_free_reserved_data_space(struct inode *inode, u64 bytes)
3204 struct btrfs_root *root = BTRFS_I(inode)->root;
3205 struct btrfs_space_info *data_sinfo;
3207 /* make sure bytes are sectorsize aligned */
3208 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3210 data_sinfo = BTRFS_I(inode)->space_info;
3211 spin_lock(&data_sinfo->lock);
3212 data_sinfo->bytes_may_use -= bytes;
3213 BTRFS_I(inode)->reserved_bytes -= bytes;
3214 spin_unlock(&data_sinfo->lock);
3217 static void force_metadata_allocation(struct btrfs_fs_info *info)
3219 struct list_head *head = &info->space_info;
3220 struct btrfs_space_info *found;
3223 list_for_each_entry_rcu(found, head, list) {
3224 if (found->flags & BTRFS_BLOCK_GROUP_METADATA)
3225 found->force_alloc = 1;
3230 static int should_alloc_chunk(struct btrfs_root *root,
3231 struct btrfs_space_info *sinfo, u64 alloc_bytes)
3233 u64 num_bytes = sinfo->total_bytes - sinfo->bytes_readonly;
3236 if (sinfo->bytes_used + sinfo->bytes_reserved +
3237 alloc_bytes + 256 * 1024 * 1024 < num_bytes)
3240 if (sinfo->bytes_used + sinfo->bytes_reserved +
3241 alloc_bytes < div_factor(num_bytes, 8))
3244 thresh = btrfs_super_total_bytes(&root->fs_info->super_copy);
3245 thresh = max_t(u64, 256 * 1024 * 1024, div_factor_fine(thresh, 5));
3247 if (num_bytes > thresh && sinfo->bytes_used < div_factor(num_bytes, 3))
3253 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
3254 struct btrfs_root *extent_root, u64 alloc_bytes,
3255 u64 flags, int force)
3257 struct btrfs_space_info *space_info;
3258 struct btrfs_fs_info *fs_info = extent_root->fs_info;
3261 mutex_lock(&fs_info->chunk_mutex);
3263 flags = btrfs_reduce_alloc_profile(extent_root, flags);
3265 space_info = __find_space_info(extent_root->fs_info, flags);
3267 ret = update_space_info(extent_root->fs_info, flags,
3271 BUG_ON(!space_info);
3273 spin_lock(&space_info->lock);
3274 if (space_info->force_alloc)
3276 if (space_info->full) {
3277 spin_unlock(&space_info->lock);
3281 if (!force && !should_alloc_chunk(extent_root, space_info,
3283 spin_unlock(&space_info->lock);
3286 spin_unlock(&space_info->lock);
3289 * If we have mixed data/metadata chunks we want to make sure we keep
3290 * allocating mixed chunks instead of individual chunks.
3292 if (btrfs_mixed_space_info(space_info))
3293 flags |= (BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA);
3296 * if we're doing a data chunk, go ahead and make sure that
3297 * we keep a reasonable number of metadata chunks allocated in the
3300 if (flags & BTRFS_BLOCK_GROUP_DATA && fs_info->metadata_ratio) {
3301 fs_info->data_chunk_allocations++;
3302 if (!(fs_info->data_chunk_allocations %
3303 fs_info->metadata_ratio))
3304 force_metadata_allocation(fs_info);
3307 ret = btrfs_alloc_chunk(trans, extent_root, flags);
3308 spin_lock(&space_info->lock);
3310 space_info->full = 1;
3313 space_info->force_alloc = 0;
3314 spin_unlock(&space_info->lock);
3316 mutex_unlock(&extent_root->fs_info->chunk_mutex);
3321 * shrink metadata reservation for delalloc
3323 static int shrink_delalloc(struct btrfs_trans_handle *trans,
3324 struct btrfs_root *root, u64 to_reclaim, int sync)
3326 struct btrfs_block_rsv *block_rsv;
3327 struct btrfs_space_info *space_info;
3332 int nr_pages = (2 * 1024 * 1024) >> PAGE_CACHE_SHIFT;
3334 block_rsv = &root->fs_info->delalloc_block_rsv;
3335 space_info = block_rsv->space_info;
3338 reserved = space_info->bytes_reserved;
3343 max_reclaim = min(reserved, to_reclaim);
3346 /* have the flusher threads jump in and do some IO */
3348 nr_pages = min_t(unsigned long, nr_pages,
3349 root->fs_info->delalloc_bytes >> PAGE_CACHE_SHIFT);
3350 writeback_inodes_sb_nr_if_idle(root->fs_info->sb, nr_pages);
3352 spin_lock(&space_info->lock);
3353 if (reserved > space_info->bytes_reserved)
3354 reclaimed += reserved - space_info->bytes_reserved;
3355 reserved = space_info->bytes_reserved;
3356 spin_unlock(&space_info->lock);
3358 if (reserved == 0 || reclaimed >= max_reclaim)
3361 if (trans && trans->transaction->blocked)
3364 __set_current_state(TASK_INTERRUPTIBLE);
3365 schedule_timeout(pause);
3367 if (pause > HZ / 10)
3371 return reclaimed >= to_reclaim;
3375 * Retries tells us how many times we've called reserve_metadata_bytes. The
3376 * idea is if this is the first call (retries == 0) then we will add to our
3377 * reserved count if we can't make the allocation in order to hold our place
3378 * while we go and try and free up space. That way for retries > 1 we don't try
3379 * and add space, we just check to see if the amount of unused space is >= the
3380 * total space, meaning that our reservation is valid.
3382 * However if we don't intend to retry this reservation, pass -1 as retries so
3383 * that it short circuits this logic.
3385 static int reserve_metadata_bytes(struct btrfs_trans_handle *trans,
3386 struct btrfs_root *root,
3387 struct btrfs_block_rsv *block_rsv,
3388 u64 orig_bytes, int flush)
3390 struct btrfs_space_info *space_info = block_rsv->space_info;
3392 u64 num_bytes = orig_bytes;
3395 bool reserved = false;
3396 bool committed = false;
3403 spin_lock(&space_info->lock);
3404 unused = space_info->bytes_used + space_info->bytes_reserved +
3405 space_info->bytes_pinned + space_info->bytes_readonly +
3406 space_info->bytes_may_use;
3409 * The idea here is that we've not already over-reserved the block group
3410 * then we can go ahead and save our reservation first and then start
3411 * flushing if we need to. Otherwise if we've already overcommitted
3412 * lets start flushing stuff first and then come back and try to make
3415 if (unused <= space_info->total_bytes) {
3416 unused -= space_info->total_bytes;
3417 if (unused >= num_bytes) {
3419 space_info->bytes_reserved += orig_bytes;
3423 * Ok set num_bytes to orig_bytes since we aren't
3424 * overocmmitted, this way we only try and reclaim what
3427 num_bytes = orig_bytes;
3431 * Ok we're over committed, set num_bytes to the overcommitted
3432 * amount plus the amount of bytes that we need for this
3435 num_bytes = unused - space_info->total_bytes +
3436 (orig_bytes * (retries + 1));
3440 * Couldn't make our reservation, save our place so while we're trying
3441 * to reclaim space we can actually use it instead of somebody else
3442 * stealing it from us.
3444 if (ret && !reserved) {
3445 space_info->bytes_reserved += orig_bytes;
3449 spin_unlock(&space_info->lock);
3458 * We do synchronous shrinking since we don't actually unreserve
3459 * metadata until after the IO is completed.
3461 ret = shrink_delalloc(trans, root, num_bytes, 1);
3468 * So if we were overcommitted it's possible that somebody else flushed
3469 * out enough space and we simply didn't have enough space to reclaim,
3470 * so go back around and try again.
3477 spin_lock(&space_info->lock);
3479 * Not enough space to be reclaimed, don't bother committing the
3482 if (space_info->bytes_pinned < orig_bytes)
3484 spin_unlock(&space_info->lock);
3489 if (trans || committed)
3493 trans = btrfs_join_transaction(root, 1);
3496 ret = btrfs_commit_transaction(trans, root);
3505 spin_lock(&space_info->lock);
3506 space_info->bytes_reserved -= orig_bytes;
3507 spin_unlock(&space_info->lock);
3513 static struct btrfs_block_rsv *get_block_rsv(struct btrfs_trans_handle *trans,
3514 struct btrfs_root *root)
3516 struct btrfs_block_rsv *block_rsv;
3518 block_rsv = trans->block_rsv;
3520 block_rsv = root->block_rsv;
3523 block_rsv = &root->fs_info->empty_block_rsv;
3528 static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
3532 spin_lock(&block_rsv->lock);
3533 if (block_rsv->reserved >= num_bytes) {
3534 block_rsv->reserved -= num_bytes;
3535 if (block_rsv->reserved < block_rsv->size)
3536 block_rsv->full = 0;
3539 spin_unlock(&block_rsv->lock);
3543 static void block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
3544 u64 num_bytes, int update_size)
3546 spin_lock(&block_rsv->lock);
3547 block_rsv->reserved += num_bytes;
3549 block_rsv->size += num_bytes;
3550 else if (block_rsv->reserved >= block_rsv->size)
3551 block_rsv->full = 1;
3552 spin_unlock(&block_rsv->lock);
3555 void block_rsv_release_bytes(struct btrfs_block_rsv *block_rsv,
3556 struct btrfs_block_rsv *dest, u64 num_bytes)
3558 struct btrfs_space_info *space_info = block_rsv->space_info;
3560 spin_lock(&block_rsv->lock);
3561 if (num_bytes == (u64)-1)
3562 num_bytes = block_rsv->size;
3563 block_rsv->size -= num_bytes;
3564 if (block_rsv->reserved >= block_rsv->size) {
3565 num_bytes = block_rsv->reserved - block_rsv->size;
3566 block_rsv->reserved = block_rsv->size;
3567 block_rsv->full = 1;
3571 spin_unlock(&block_rsv->lock);
3573 if (num_bytes > 0) {
3575 block_rsv_add_bytes(dest, num_bytes, 0);
3577 spin_lock(&space_info->lock);
3578 space_info->bytes_reserved -= num_bytes;
3579 spin_unlock(&space_info->lock);
3584 static int block_rsv_migrate_bytes(struct btrfs_block_rsv *src,
3585 struct btrfs_block_rsv *dst, u64 num_bytes)
3589 ret = block_rsv_use_bytes(src, num_bytes);
3593 block_rsv_add_bytes(dst, num_bytes, 1);
3597 void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv)
3599 memset(rsv, 0, sizeof(*rsv));
3600 spin_lock_init(&rsv->lock);
3601 atomic_set(&rsv->usage, 1);
3603 INIT_LIST_HEAD(&rsv->list);
3606 struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_root *root)
3608 struct btrfs_block_rsv *block_rsv;
3609 struct btrfs_fs_info *fs_info = root->fs_info;
3611 block_rsv = kmalloc(sizeof(*block_rsv), GFP_NOFS);
3615 btrfs_init_block_rsv(block_rsv);
3616 block_rsv->space_info = __find_space_info(fs_info,
3617 BTRFS_BLOCK_GROUP_METADATA);
3621 void btrfs_free_block_rsv(struct btrfs_root *root,
3622 struct btrfs_block_rsv *rsv)
3624 if (rsv && atomic_dec_and_test(&rsv->usage)) {
3625 btrfs_block_rsv_release(root, rsv, (u64)-1);
3632 * make the block_rsv struct be able to capture freed space.
3633 * the captured space will re-add to the the block_rsv struct
3634 * after transaction commit
3636 void btrfs_add_durable_block_rsv(struct btrfs_fs_info *fs_info,
3637 struct btrfs_block_rsv *block_rsv)
3639 block_rsv->durable = 1;
3640 mutex_lock(&fs_info->durable_block_rsv_mutex);
3641 list_add_tail(&block_rsv->list, &fs_info->durable_block_rsv_list);
3642 mutex_unlock(&fs_info->durable_block_rsv_mutex);
3645 int btrfs_block_rsv_add(struct btrfs_trans_handle *trans,
3646 struct btrfs_root *root,
3647 struct btrfs_block_rsv *block_rsv,
3655 ret = reserve_metadata_bytes(trans, root, block_rsv, num_bytes, 1);
3657 block_rsv_add_bytes(block_rsv, num_bytes, 1);
3664 int btrfs_block_rsv_check(struct btrfs_trans_handle *trans,
3665 struct btrfs_root *root,
3666 struct btrfs_block_rsv *block_rsv,
3667 u64 min_reserved, int min_factor)
3670 int commit_trans = 0;
3676 spin_lock(&block_rsv->lock);
3678 num_bytes = div_factor(block_rsv->size, min_factor);
3679 if (min_reserved > num_bytes)
3680 num_bytes = min_reserved;
3682 if (block_rsv->reserved >= num_bytes) {
3685 num_bytes -= block_rsv->reserved;
3686 if (block_rsv->durable &&
3687 block_rsv->freed[0] + block_rsv->freed[1] >= num_bytes)
3690 spin_unlock(&block_rsv->lock);
3694 if (block_rsv->refill_used) {
3695 ret = reserve_metadata_bytes(trans, root, block_rsv,
3698 block_rsv_add_bytes(block_rsv, num_bytes, 0);
3707 trans = btrfs_join_transaction(root, 1);
3708 BUG_ON(IS_ERR(trans));
3709 ret = btrfs_commit_transaction(trans, root);
3714 printk(KERN_INFO"block_rsv size %llu reserved %llu freed %llu %llu\n",
3715 block_rsv->size, block_rsv->reserved,
3716 block_rsv->freed[0], block_rsv->freed[1]);
3721 int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,
3722 struct btrfs_block_rsv *dst_rsv,
3725 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3728 void btrfs_block_rsv_release(struct btrfs_root *root,
3729 struct btrfs_block_rsv *block_rsv,
3732 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
3733 if (global_rsv->full || global_rsv == block_rsv ||
3734 block_rsv->space_info != global_rsv->space_info)
3736 block_rsv_release_bytes(block_rsv, global_rsv, num_bytes);
3740 * helper to calculate size of global block reservation.
3741 * the desired value is sum of space used by extent tree,
3742 * checksum tree and root tree
3744 static u64 calc_global_metadata_size(struct btrfs_fs_info *fs_info)
3746 struct btrfs_space_info *sinfo;
3750 int csum_size = btrfs_super_csum_size(&fs_info->super_copy);
3753 * per tree used space accounting can be inaccuracy, so we
3756 spin_lock(&fs_info->extent_root->accounting_lock);
3757 num_bytes = btrfs_root_used(&fs_info->extent_root->root_item);
3758 spin_unlock(&fs_info->extent_root->accounting_lock);
3760 spin_lock(&fs_info->csum_root->accounting_lock);
3761 num_bytes += btrfs_root_used(&fs_info->csum_root->root_item);
3762 spin_unlock(&fs_info->csum_root->accounting_lock);
3764 spin_lock(&fs_info->tree_root->accounting_lock);
3765 num_bytes += btrfs_root_used(&fs_info->tree_root->root_item);
3766 spin_unlock(&fs_info->tree_root->accounting_lock);
3768 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_DATA);
3769 spin_lock(&sinfo->lock);
3770 data_used = sinfo->bytes_used;
3771 spin_unlock(&sinfo->lock);
3773 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
3774 spin_lock(&sinfo->lock);
3775 if (sinfo->flags & BTRFS_BLOCK_GROUP_DATA)
3777 meta_used = sinfo->bytes_used;
3778 spin_unlock(&sinfo->lock);
3780 num_bytes = (data_used >> fs_info->sb->s_blocksize_bits) *
3782 num_bytes += div64_u64(data_used + meta_used, 50);
3784 if (num_bytes * 3 > meta_used)
3785 num_bytes = div64_u64(meta_used, 3);
3787 return ALIGN(num_bytes, fs_info->extent_root->leafsize << 10);
3790 static void update_global_block_rsv(struct btrfs_fs_info *fs_info)
3792 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
3793 struct btrfs_space_info *sinfo = block_rsv->space_info;
3796 num_bytes = calc_global_metadata_size(fs_info);
3798 spin_lock(&block_rsv->lock);
3799 spin_lock(&sinfo->lock);
3801 block_rsv->size = num_bytes;
3803 num_bytes = sinfo->bytes_used + sinfo->bytes_pinned +
3804 sinfo->bytes_reserved + sinfo->bytes_readonly +
3805 sinfo->bytes_may_use;
3807 if (sinfo->total_bytes > num_bytes) {
3808 num_bytes = sinfo->total_bytes - num_bytes;
3809 block_rsv->reserved += num_bytes;
3810 sinfo->bytes_reserved += num_bytes;
3813 if (block_rsv->reserved >= block_rsv->size) {
3814 num_bytes = block_rsv->reserved - block_rsv->size;
3815 sinfo->bytes_reserved -= num_bytes;
3816 block_rsv->reserved = block_rsv->size;
3817 block_rsv->full = 1;
3820 printk(KERN_INFO"global block rsv size %llu reserved %llu\n",
3821 block_rsv->size, block_rsv->reserved);
3823 spin_unlock(&sinfo->lock);
3824 spin_unlock(&block_rsv->lock);
3827 static void init_global_block_rsv(struct btrfs_fs_info *fs_info)
3829 struct btrfs_space_info *space_info;
3831 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
3832 fs_info->chunk_block_rsv.space_info = space_info;
3833 fs_info->chunk_block_rsv.priority = 10;
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->global_block_rsv.priority = 10;
3838 fs_info->global_block_rsv.refill_used = 1;
3839 fs_info->delalloc_block_rsv.space_info = space_info;
3840 fs_info->trans_block_rsv.space_info = space_info;
3841 fs_info->empty_block_rsv.space_info = space_info;
3842 fs_info->empty_block_rsv.priority = 10;
3844 fs_info->extent_root->block_rsv = &fs_info->global_block_rsv;
3845 fs_info->csum_root->block_rsv = &fs_info->global_block_rsv;
3846 fs_info->dev_root->block_rsv = &fs_info->global_block_rsv;
3847 fs_info->tree_root->block_rsv = &fs_info->global_block_rsv;
3848 fs_info->chunk_root->block_rsv = &fs_info->chunk_block_rsv;
3850 btrfs_add_durable_block_rsv(fs_info, &fs_info->global_block_rsv);
3852 btrfs_add_durable_block_rsv(fs_info, &fs_info->delalloc_block_rsv);
3854 update_global_block_rsv(fs_info);
3857 static void release_global_block_rsv(struct btrfs_fs_info *fs_info)
3859 block_rsv_release_bytes(&fs_info->global_block_rsv, NULL, (u64)-1);
3860 WARN_ON(fs_info->delalloc_block_rsv.size > 0);
3861 WARN_ON(fs_info->delalloc_block_rsv.reserved > 0);
3862 WARN_ON(fs_info->trans_block_rsv.size > 0);
3863 WARN_ON(fs_info->trans_block_rsv.reserved > 0);
3864 WARN_ON(fs_info->chunk_block_rsv.size > 0);
3865 WARN_ON(fs_info->chunk_block_rsv.reserved > 0);
3868 static u64 calc_trans_metadata_size(struct btrfs_root *root, int num_items)
3870 return (root->leafsize + root->nodesize * (BTRFS_MAX_LEVEL - 1)) *
3874 int btrfs_trans_reserve_metadata(struct btrfs_trans_handle *trans,
3875 struct btrfs_root *root,
3881 if (num_items == 0 || root->fs_info->chunk_root == root)
3884 num_bytes = calc_trans_metadata_size(root, num_items);
3885 ret = btrfs_block_rsv_add(trans, root, &root->fs_info->trans_block_rsv,
3888 trans->bytes_reserved += num_bytes;
3889 trans->block_rsv = &root->fs_info->trans_block_rsv;
3894 void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans,
3895 struct btrfs_root *root)
3897 if (!trans->bytes_reserved)
3900 BUG_ON(trans->block_rsv != &root->fs_info->trans_block_rsv);
3901 btrfs_block_rsv_release(root, trans->block_rsv,
3902 trans->bytes_reserved);
3903 trans->bytes_reserved = 0;
3906 int btrfs_orphan_reserve_metadata(struct btrfs_trans_handle *trans,
3907 struct inode *inode)
3909 struct btrfs_root *root = BTRFS_I(inode)->root;
3910 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
3911 struct btrfs_block_rsv *dst_rsv = root->orphan_block_rsv;
3914 * one for deleting orphan item, one for updating inode and
3915 * two for calling btrfs_truncate_inode_items.
3917 * btrfs_truncate_inode_items is a delete operation, it frees
3918 * more space than it uses in most cases. So two units of
3919 * metadata space should be enough for calling it many times.
3920 * If all of the metadata space is used, we can commit
3921 * transaction and use space it freed.
3923 u64 num_bytes = calc_trans_metadata_size(root, 4);
3924 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3927 void btrfs_orphan_release_metadata(struct inode *inode)
3929 struct btrfs_root *root = BTRFS_I(inode)->root;
3930 u64 num_bytes = calc_trans_metadata_size(root, 4);
3931 btrfs_block_rsv_release(root, root->orphan_block_rsv, num_bytes);
3934 int btrfs_snap_reserve_metadata(struct btrfs_trans_handle *trans,
3935 struct btrfs_pending_snapshot *pending)
3937 struct btrfs_root *root = pending->root;
3938 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
3939 struct btrfs_block_rsv *dst_rsv = &pending->block_rsv;
3941 * two for root back/forward refs, two for directory entries
3942 * and one for root of the snapshot.
3944 u64 num_bytes = calc_trans_metadata_size(root, 5);
3945 dst_rsv->space_info = src_rsv->space_info;
3946 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3949 static u64 calc_csum_metadata_size(struct inode *inode, u64 num_bytes)
3951 return num_bytes >>= 3;
3954 int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
3956 struct btrfs_root *root = BTRFS_I(inode)->root;
3957 struct btrfs_block_rsv *block_rsv = &root->fs_info->delalloc_block_rsv;
3962 if (btrfs_transaction_in_commit(root->fs_info))
3963 schedule_timeout(1);
3965 num_bytes = ALIGN(num_bytes, root->sectorsize);
3967 spin_lock(&BTRFS_I(inode)->accounting_lock);
3968 nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents) + 1;
3969 if (nr_extents > BTRFS_I(inode)->reserved_extents) {
3970 nr_extents -= BTRFS_I(inode)->reserved_extents;
3971 to_reserve = calc_trans_metadata_size(root, nr_extents);
3976 spin_unlock(&BTRFS_I(inode)->accounting_lock);
3978 to_reserve += calc_csum_metadata_size(inode, num_bytes);
3979 ret = reserve_metadata_bytes(NULL, root, block_rsv, to_reserve, 1);
3983 spin_lock(&BTRFS_I(inode)->accounting_lock);
3984 BTRFS_I(inode)->reserved_extents += nr_extents;
3985 atomic_inc(&BTRFS_I(inode)->outstanding_extents);
3986 spin_unlock(&BTRFS_I(inode)->accounting_lock);
3988 block_rsv_add_bytes(block_rsv, to_reserve, 1);
3990 if (block_rsv->size > 512 * 1024 * 1024)
3991 shrink_delalloc(NULL, root, to_reserve, 0);
3996 void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes)
3998 struct btrfs_root *root = BTRFS_I(inode)->root;
4002 num_bytes = ALIGN(num_bytes, root->sectorsize);
4003 atomic_dec(&BTRFS_I(inode)->outstanding_extents);
4005 spin_lock(&BTRFS_I(inode)->accounting_lock);
4006 nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents);
4007 if (nr_extents < BTRFS_I(inode)->reserved_extents) {
4008 nr_extents = BTRFS_I(inode)->reserved_extents - nr_extents;
4009 BTRFS_I(inode)->reserved_extents -= nr_extents;
4013 spin_unlock(&BTRFS_I(inode)->accounting_lock);
4015 to_free = calc_csum_metadata_size(inode, num_bytes);
4017 to_free += calc_trans_metadata_size(root, nr_extents);
4019 btrfs_block_rsv_release(root, &root->fs_info->delalloc_block_rsv,
4023 int btrfs_delalloc_reserve_space(struct inode *inode, u64 num_bytes)
4027 ret = btrfs_check_data_free_space(inode, num_bytes);
4031 ret = btrfs_delalloc_reserve_metadata(inode, num_bytes);
4033 btrfs_free_reserved_data_space(inode, num_bytes);
4040 void btrfs_delalloc_release_space(struct inode *inode, u64 num_bytes)
4042 btrfs_delalloc_release_metadata(inode, num_bytes);
4043 btrfs_free_reserved_data_space(inode, num_bytes);
4046 static int update_block_group(struct btrfs_trans_handle *trans,
4047 struct btrfs_root *root,
4048 u64 bytenr, u64 num_bytes, int alloc)
4050 struct btrfs_block_group_cache *cache = NULL;
4051 struct btrfs_fs_info *info = root->fs_info;
4052 u64 total = num_bytes;
4057 /* block accounting for super block */
4058 spin_lock(&info->delalloc_lock);
4059 old_val = btrfs_super_bytes_used(&info->super_copy);
4061 old_val += num_bytes;
4063 old_val -= num_bytes;
4064 btrfs_set_super_bytes_used(&info->super_copy, old_val);
4065 spin_unlock(&info->delalloc_lock);
4068 cache = btrfs_lookup_block_group(info, bytenr);
4071 if (cache->flags & (BTRFS_BLOCK_GROUP_DUP |
4072 BTRFS_BLOCK_GROUP_RAID1 |
4073 BTRFS_BLOCK_GROUP_RAID10))
4078 * If this block group has free space cache written out, we
4079 * need to make sure to load it if we are removing space. This
4080 * is because we need the unpinning stage to actually add the
4081 * space back to the block group, otherwise we will leak space.
4083 if (!alloc && cache->cached == BTRFS_CACHE_NO)
4084 cache_block_group(cache, trans, 1);
4086 byte_in_group = bytenr - cache->key.objectid;
4087 WARN_ON(byte_in_group > cache->key.offset);
4089 spin_lock(&cache->space_info->lock);
4090 spin_lock(&cache->lock);
4092 if (btrfs_super_cache_generation(&info->super_copy) != 0 &&
4093 cache->disk_cache_state < BTRFS_DC_CLEAR)
4094 cache->disk_cache_state = BTRFS_DC_CLEAR;
4097 old_val = btrfs_block_group_used(&cache->item);
4098 num_bytes = min(total, cache->key.offset - byte_in_group);
4100 old_val += num_bytes;
4101 btrfs_set_block_group_used(&cache->item, old_val);
4102 cache->reserved -= num_bytes;
4103 cache->space_info->bytes_reserved -= num_bytes;
4104 cache->space_info->bytes_used += num_bytes;
4105 cache->space_info->disk_used += num_bytes * factor;
4106 spin_unlock(&cache->lock);
4107 spin_unlock(&cache->space_info->lock);
4109 old_val -= num_bytes;
4110 btrfs_set_block_group_used(&cache->item, old_val);
4111 cache->pinned += num_bytes;
4112 cache->space_info->bytes_pinned += num_bytes;
4113 cache->space_info->bytes_used -= num_bytes;
4114 cache->space_info->disk_used -= num_bytes * factor;
4115 spin_unlock(&cache->lock);
4116 spin_unlock(&cache->space_info->lock);
4118 set_extent_dirty(info->pinned_extents,
4119 bytenr, bytenr + num_bytes - 1,
4120 GFP_NOFS | __GFP_NOFAIL);
4122 btrfs_put_block_group(cache);
4124 bytenr += num_bytes;
4129 static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
4131 struct btrfs_block_group_cache *cache;
4134 cache = btrfs_lookup_first_block_group(root->fs_info, search_start);
4138 bytenr = cache->key.objectid;
4139 btrfs_put_block_group(cache);
4144 static int pin_down_extent(struct btrfs_root *root,
4145 struct btrfs_block_group_cache *cache,
4146 u64 bytenr, u64 num_bytes, int reserved)
4148 spin_lock(&cache->space_info->lock);
4149 spin_lock(&cache->lock);
4150 cache->pinned += num_bytes;
4151 cache->space_info->bytes_pinned += num_bytes;
4153 cache->reserved -= num_bytes;
4154 cache->space_info->bytes_reserved -= num_bytes;
4156 spin_unlock(&cache->lock);
4157 spin_unlock(&cache->space_info->lock);
4159 set_extent_dirty(root->fs_info->pinned_extents, bytenr,
4160 bytenr + num_bytes - 1, GFP_NOFS | __GFP_NOFAIL);
4165 * this function must be called within transaction
4167 int btrfs_pin_extent(struct btrfs_root *root,
4168 u64 bytenr, u64 num_bytes, int reserved)
4170 struct btrfs_block_group_cache *cache;
4172 cache = btrfs_lookup_block_group(root->fs_info, bytenr);
4175 pin_down_extent(root, cache, bytenr, num_bytes, reserved);
4177 btrfs_put_block_group(cache);
4182 * update size of reserved extents. this function may return -EAGAIN
4183 * if 'reserve' is true or 'sinfo' is false.
4185 static int update_reserved_bytes(struct btrfs_block_group_cache *cache,
4186 u64 num_bytes, int reserve, int sinfo)
4190 struct btrfs_space_info *space_info = cache->space_info;
4191 spin_lock(&space_info->lock);
4192 spin_lock(&cache->lock);
4197 cache->reserved += num_bytes;
4198 space_info->bytes_reserved += num_bytes;
4202 space_info->bytes_readonly += num_bytes;
4203 cache->reserved -= num_bytes;
4204 space_info->bytes_reserved -= num_bytes;
4206 spin_unlock(&cache->lock);
4207 spin_unlock(&space_info->lock);
4209 spin_lock(&cache->lock);
4214 cache->reserved += num_bytes;
4216 cache->reserved -= num_bytes;
4218 spin_unlock(&cache->lock);
4223 int btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
4224 struct btrfs_root *root)
4226 struct btrfs_fs_info *fs_info = root->fs_info;
4227 struct btrfs_caching_control *next;
4228 struct btrfs_caching_control *caching_ctl;
4229 struct btrfs_block_group_cache *cache;
4231 down_write(&fs_info->extent_commit_sem);
4233 list_for_each_entry_safe(caching_ctl, next,
4234 &fs_info->caching_block_groups, list) {
4235 cache = caching_ctl->block_group;
4236 if (block_group_cache_done(cache)) {
4237 cache->last_byte_to_unpin = (u64)-1;
4238 list_del_init(&caching_ctl->list);
4239 put_caching_control(caching_ctl);
4241 cache->last_byte_to_unpin = caching_ctl->progress;
4245 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
4246 fs_info->pinned_extents = &fs_info->freed_extents[1];
4248 fs_info->pinned_extents = &fs_info->freed_extents[0];
4250 up_write(&fs_info->extent_commit_sem);
4252 update_global_block_rsv(fs_info);
4256 static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
4258 struct btrfs_fs_info *fs_info = root->fs_info;
4259 struct btrfs_block_group_cache *cache = NULL;
4262 while (start <= end) {
4264 start >= cache->key.objectid + cache->key.offset) {
4266 btrfs_put_block_group(cache);
4267 cache = btrfs_lookup_block_group(fs_info, start);
4271 len = cache->key.objectid + cache->key.offset - start;
4272 len = min(len, end + 1 - start);
4274 if (start < cache->last_byte_to_unpin) {
4275 len = min(len, cache->last_byte_to_unpin - start);
4276 btrfs_add_free_space(cache, start, len);
4281 spin_lock(&cache->space_info->lock);
4282 spin_lock(&cache->lock);
4283 cache->pinned -= len;
4284 cache->space_info->bytes_pinned -= len;
4286 cache->space_info->bytes_readonly += len;
4287 } else if (cache->reserved_pinned > 0) {
4288 len = min(len, cache->reserved_pinned);
4289 cache->reserved_pinned -= len;
4290 cache->space_info->bytes_reserved += len;
4292 spin_unlock(&cache->lock);
4293 spin_unlock(&cache->space_info->lock);
4297 btrfs_put_block_group(cache);
4301 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
4302 struct btrfs_root *root)
4304 struct btrfs_fs_info *fs_info = root->fs_info;
4305 struct extent_io_tree *unpin;
4306 struct btrfs_block_rsv *block_rsv;
4307 struct btrfs_block_rsv *next_rsv;
4313 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
4314 unpin = &fs_info->freed_extents[1];
4316 unpin = &fs_info->freed_extents[0];
4319 ret = find_first_extent_bit(unpin, 0, &start, &end,
4324 ret = btrfs_discard_extent(root, start, end + 1 - start);
4326 clear_extent_dirty(unpin, start, end, GFP_NOFS);
4327 unpin_extent_range(root, start, end);
4331 mutex_lock(&fs_info->durable_block_rsv_mutex);
4332 list_for_each_entry_safe(block_rsv, next_rsv,
4333 &fs_info->durable_block_rsv_list, list) {
4335 idx = trans->transid & 0x1;
4336 if (block_rsv->freed[idx] > 0) {
4337 block_rsv_add_bytes(block_rsv,
4338 block_rsv->freed[idx], 0);
4339 block_rsv->freed[idx] = 0;
4341 if (atomic_read(&block_rsv->usage) == 0) {
4342 btrfs_block_rsv_release(root, block_rsv, (u64)-1);
4344 if (block_rsv->freed[0] == 0 &&
4345 block_rsv->freed[1] == 0) {
4346 list_del_init(&block_rsv->list);
4350 btrfs_block_rsv_release(root, block_rsv, 0);
4353 mutex_unlock(&fs_info->durable_block_rsv_mutex);
4358 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
4359 struct btrfs_root *root,
4360 u64 bytenr, u64 num_bytes, u64 parent,
4361 u64 root_objectid, u64 owner_objectid,
4362 u64 owner_offset, int refs_to_drop,
4363 struct btrfs_delayed_extent_op *extent_op)
4365 struct btrfs_key key;
4366 struct btrfs_path *path;
4367 struct btrfs_fs_info *info = root->fs_info;
4368 struct btrfs_root *extent_root = info->extent_root;
4369 struct extent_buffer *leaf;
4370 struct btrfs_extent_item *ei;
4371 struct btrfs_extent_inline_ref *iref;
4374 int extent_slot = 0;
4375 int found_extent = 0;
4380 path = btrfs_alloc_path();
4385 path->leave_spinning = 1;
4387 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
4388 BUG_ON(!is_data && refs_to_drop != 1);
4390 ret = lookup_extent_backref(trans, extent_root, path, &iref,
4391 bytenr, num_bytes, parent,
4392 root_objectid, owner_objectid,
4395 extent_slot = path->slots[0];
4396 while (extent_slot >= 0) {
4397 btrfs_item_key_to_cpu(path->nodes[0], &key,
4399 if (key.objectid != bytenr)
4401 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
4402 key.offset == num_bytes) {
4406 if (path->slots[0] - extent_slot > 5)
4410 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
4411 item_size = btrfs_item_size_nr(path->nodes[0], extent_slot);
4412 if (found_extent && item_size < sizeof(*ei))
4415 if (!found_extent) {
4417 ret = remove_extent_backref(trans, extent_root, path,
4421 btrfs_release_path(extent_root, path);
4422 path->leave_spinning = 1;
4424 key.objectid = bytenr;
4425 key.type = BTRFS_EXTENT_ITEM_KEY;
4426 key.offset = num_bytes;
4428 ret = btrfs_search_slot(trans, extent_root,
4431 printk(KERN_ERR "umm, got %d back from search"
4432 ", was looking for %llu\n", ret,
4433 (unsigned long long)bytenr);
4434 btrfs_print_leaf(extent_root, path->nodes[0]);
4437 extent_slot = path->slots[0];
4440 btrfs_print_leaf(extent_root, path->nodes[0]);
4442 printk(KERN_ERR "btrfs unable to find ref byte nr %llu "
4443 "parent %llu root %llu owner %llu offset %llu\n",
4444 (unsigned long long)bytenr,
4445 (unsigned long long)parent,
4446 (unsigned long long)root_objectid,
4447 (unsigned long long)owner_objectid,
4448 (unsigned long long)owner_offset);
4451 leaf = path->nodes[0];
4452 item_size = btrfs_item_size_nr(leaf, extent_slot);
4453 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
4454 if (item_size < sizeof(*ei)) {
4455 BUG_ON(found_extent || extent_slot != path->slots[0]);
4456 ret = convert_extent_item_v0(trans, extent_root, path,
4460 btrfs_release_path(extent_root, path);
4461 path->leave_spinning = 1;
4463 key.objectid = bytenr;
4464 key.type = BTRFS_EXTENT_ITEM_KEY;
4465 key.offset = num_bytes;
4467 ret = btrfs_search_slot(trans, extent_root, &key, path,
4470 printk(KERN_ERR "umm, got %d back from search"
4471 ", was looking for %llu\n", ret,
4472 (unsigned long long)bytenr);
4473 btrfs_print_leaf(extent_root, path->nodes[0]);
4476 extent_slot = path->slots[0];
4477 leaf = path->nodes[0];
4478 item_size = btrfs_item_size_nr(leaf, extent_slot);
4481 BUG_ON(item_size < sizeof(*ei));
4482 ei = btrfs_item_ptr(leaf, extent_slot,
4483 struct btrfs_extent_item);
4484 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID) {
4485 struct btrfs_tree_block_info *bi;
4486 BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
4487 bi = (struct btrfs_tree_block_info *)(ei + 1);
4488 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
4491 refs = btrfs_extent_refs(leaf, ei);
4492 BUG_ON(refs < refs_to_drop);
4493 refs -= refs_to_drop;
4497 __run_delayed_extent_op(extent_op, leaf, ei);
4499 * In the case of inline back ref, reference count will
4500 * be updated by remove_extent_backref
4503 BUG_ON(!found_extent);
4505 btrfs_set_extent_refs(leaf, ei, refs);
4506 btrfs_mark_buffer_dirty(leaf);
4509 ret = remove_extent_backref(trans, extent_root, path,
4516 BUG_ON(is_data && refs_to_drop !=
4517 extent_data_ref_count(root, path, iref));
4519 BUG_ON(path->slots[0] != extent_slot);
4521 BUG_ON(path->slots[0] != extent_slot + 1);
4522 path->slots[0] = extent_slot;
4527 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
4530 btrfs_release_path(extent_root, path);
4533 ret = btrfs_del_csums(trans, root, bytenr, num_bytes);
4536 invalidate_mapping_pages(info->btree_inode->i_mapping,
4537 bytenr >> PAGE_CACHE_SHIFT,
4538 (bytenr + num_bytes - 1) >> PAGE_CACHE_SHIFT);
4541 ret = update_block_group(trans, root, bytenr, num_bytes, 0);
4544 btrfs_free_path(path);
4549 * when we free an block, it is possible (and likely) that we free the last
4550 * delayed ref for that extent as well. This searches the delayed ref tree for
4551 * a given extent, and if there are no other delayed refs to be processed, it
4552 * removes it from the tree.
4554 static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans,
4555 struct btrfs_root *root, u64 bytenr)
4557 struct btrfs_delayed_ref_head *head;
4558 struct btrfs_delayed_ref_root *delayed_refs;
4559 struct btrfs_delayed_ref_node *ref;
4560 struct rb_node *node;
4563 delayed_refs = &trans->transaction->delayed_refs;
4564 spin_lock(&delayed_refs->lock);
4565 head = btrfs_find_delayed_ref_head(trans, bytenr);
4569 node = rb_prev(&head->node.rb_node);
4573 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
4575 /* there are still entries for this ref, we can't drop it */
4576 if (ref->bytenr == bytenr)
4579 if (head->extent_op) {
4580 if (!head->must_insert_reserved)
4582 kfree(head->extent_op);
4583 head->extent_op = NULL;
4587 * waiting for the lock here would deadlock. If someone else has it
4588 * locked they are already in the process of dropping it anyway
4590 if (!mutex_trylock(&head->mutex))
4594 * at this point we have a head with no other entries. Go
4595 * ahead and process it.
4597 head->node.in_tree = 0;
4598 rb_erase(&head->node.rb_node, &delayed_refs->root);
4600 delayed_refs->num_entries--;
4603 * we don't take a ref on the node because we're removing it from the
4604 * tree, so we just steal the ref the tree was holding.
4606 delayed_refs->num_heads--;
4607 if (list_empty(&head->cluster))
4608 delayed_refs->num_heads_ready--;
4610 list_del_init(&head->cluster);
4611 spin_unlock(&delayed_refs->lock);
4613 BUG_ON(head->extent_op);
4614 if (head->must_insert_reserved)
4617 mutex_unlock(&head->mutex);
4618 btrfs_put_delayed_ref(&head->node);
4621 spin_unlock(&delayed_refs->lock);
4625 void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
4626 struct btrfs_root *root,
4627 struct extent_buffer *buf,
4628 u64 parent, int last_ref)
4630 struct btrfs_block_rsv *block_rsv;
4631 struct btrfs_block_group_cache *cache = NULL;
4634 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4635 ret = btrfs_add_delayed_tree_ref(trans, buf->start, buf->len,
4636 parent, root->root_key.objectid,
4637 btrfs_header_level(buf),
4638 BTRFS_DROP_DELAYED_REF, NULL);
4645 block_rsv = get_block_rsv(trans, root);
4646 cache = btrfs_lookup_block_group(root->fs_info, buf->start);
4647 if (block_rsv->space_info != cache->space_info)
4650 if (btrfs_header_generation(buf) == trans->transid) {
4651 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4652 ret = check_ref_cleanup(trans, root, buf->start);
4657 if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
4658 pin_down_extent(root, cache, buf->start, buf->len, 1);
4662 WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags));
4664 btrfs_add_free_space(cache, buf->start, buf->len);
4665 ret = update_reserved_bytes(cache, buf->len, 0, 0);
4666 if (ret == -EAGAIN) {
4667 /* block group became read-only */
4668 update_reserved_bytes(cache, buf->len, 0, 1);
4673 spin_lock(&block_rsv->lock);
4674 if (block_rsv->reserved < block_rsv->size) {
4675 block_rsv->reserved += buf->len;
4678 spin_unlock(&block_rsv->lock);
4681 spin_lock(&cache->space_info->lock);
4682 cache->space_info->bytes_reserved -= buf->len;
4683 spin_unlock(&cache->space_info->lock);
4688 if (block_rsv->durable && !cache->ro) {
4690 spin_lock(&cache->lock);
4692 cache->reserved_pinned += buf->len;
4695 spin_unlock(&cache->lock);
4698 spin_lock(&block_rsv->lock);
4699 block_rsv->freed[trans->transid & 0x1] += buf->len;
4700 spin_unlock(&block_rsv->lock);
4704 btrfs_put_block_group(cache);
4707 int btrfs_free_extent(struct btrfs_trans_handle *trans,
4708 struct btrfs_root *root,
4709 u64 bytenr, u64 num_bytes, u64 parent,
4710 u64 root_objectid, u64 owner, u64 offset)
4715 * tree log blocks never actually go into the extent allocation
4716 * tree, just update pinning info and exit early.
4718 if (root_objectid == BTRFS_TREE_LOG_OBJECTID) {
4719 WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID);
4720 /* unlocks the pinned mutex */
4721 btrfs_pin_extent(root, bytenr, num_bytes, 1);
4723 } else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
4724 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
4725 parent, root_objectid, (int)owner,
4726 BTRFS_DROP_DELAYED_REF, NULL);
4729 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
4730 parent, root_objectid, owner,
4731 offset, BTRFS_DROP_DELAYED_REF, NULL);
4737 static u64 stripe_align(struct btrfs_root *root, u64 val)
4739 u64 mask = ((u64)root->stripesize - 1);
4740 u64 ret = (val + mask) & ~mask;
4745 * when we wait for progress in the block group caching, its because
4746 * our allocation attempt failed at least once. So, we must sleep
4747 * and let some progress happen before we try again.
4749 * This function will sleep at least once waiting for new free space to
4750 * show up, and then it will check the block group free space numbers
4751 * for our min num_bytes. Another option is to have it go ahead
4752 * and look in the rbtree for a free extent of a given size, but this
4756 wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
4759 struct btrfs_caching_control *caching_ctl;
4762 caching_ctl = get_caching_control(cache);
4766 wait_event(caching_ctl->wait, block_group_cache_done(cache) ||
4767 (cache->free_space >= num_bytes));
4769 put_caching_control(caching_ctl);
4774 wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
4776 struct btrfs_caching_control *caching_ctl;
4779 caching_ctl = get_caching_control(cache);
4783 wait_event(caching_ctl->wait, block_group_cache_done(cache));
4785 put_caching_control(caching_ctl);
4789 static int get_block_group_index(struct btrfs_block_group_cache *cache)
4792 if (cache->flags & BTRFS_BLOCK_GROUP_RAID10)
4794 else if (cache->flags & BTRFS_BLOCK_GROUP_RAID1)
4796 else if (cache->flags & BTRFS_BLOCK_GROUP_DUP)
4798 else if (cache->flags & BTRFS_BLOCK_GROUP_RAID0)
4805 enum btrfs_loop_type {
4806 LOOP_FIND_IDEAL = 0,
4807 LOOP_CACHING_NOWAIT = 1,
4808 LOOP_CACHING_WAIT = 2,
4809 LOOP_ALLOC_CHUNK = 3,
4810 LOOP_NO_EMPTY_SIZE = 4,
4814 * walks the btree of allocated extents and find a hole of a given size.
4815 * The key ins is changed to record the hole:
4816 * ins->objectid == block start
4817 * ins->flags = BTRFS_EXTENT_ITEM_KEY
4818 * ins->offset == number of blocks
4819 * Any available blocks before search_start are skipped.
4821 static noinline int find_free_extent(struct btrfs_trans_handle *trans,
4822 struct btrfs_root *orig_root,
4823 u64 num_bytes, u64 empty_size,
4824 u64 search_start, u64 search_end,
4825 u64 hint_byte, struct btrfs_key *ins,
4829 struct btrfs_root *root = orig_root->fs_info->extent_root;
4830 struct btrfs_free_cluster *last_ptr = NULL;
4831 struct btrfs_block_group_cache *block_group = NULL;
4832 int empty_cluster = 2 * 1024 * 1024;
4833 int allowed_chunk_alloc = 0;
4834 int done_chunk_alloc = 0;
4835 struct btrfs_space_info *space_info;
4836 int last_ptr_loop = 0;
4839 bool found_uncached_bg = false;
4840 bool failed_cluster_refill = false;
4841 bool failed_alloc = false;
4842 bool use_cluster = true;
4843 u64 ideal_cache_percent = 0;
4844 u64 ideal_cache_offset = 0;
4846 WARN_ON(num_bytes < root->sectorsize);
4847 btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
4851 space_info = __find_space_info(root->fs_info, data);
4853 printk(KERN_ERR "No space info for %d\n", data);
4858 * If the space info is for both data and metadata it means we have a
4859 * small filesystem and we can't use the clustering stuff.
4861 if (btrfs_mixed_space_info(space_info))
4862 use_cluster = false;
4864 if (orig_root->ref_cows || empty_size)
4865 allowed_chunk_alloc = 1;
4867 if (data & BTRFS_BLOCK_GROUP_METADATA && use_cluster) {
4868 last_ptr = &root->fs_info->meta_alloc_cluster;
4869 if (!btrfs_test_opt(root, SSD))
4870 empty_cluster = 64 * 1024;
4873 if ((data & BTRFS_BLOCK_GROUP_DATA) && use_cluster &&
4874 btrfs_test_opt(root, SSD)) {
4875 last_ptr = &root->fs_info->data_alloc_cluster;
4879 spin_lock(&last_ptr->lock);
4880 if (last_ptr->block_group)
4881 hint_byte = last_ptr->window_start;
4882 spin_unlock(&last_ptr->lock);
4885 search_start = max(search_start, first_logical_byte(root, 0));
4886 search_start = max(search_start, hint_byte);
4891 if (search_start == hint_byte) {
4893 block_group = btrfs_lookup_block_group(root->fs_info,
4896 * we don't want to use the block group if it doesn't match our
4897 * allocation bits, or if its not cached.
4899 * However if we are re-searching with an ideal block group
4900 * picked out then we don't care that the block group is cached.
4902 if (block_group && block_group_bits(block_group, data) &&
4903 (block_group->cached != BTRFS_CACHE_NO ||
4904 search_start == ideal_cache_offset)) {
4905 down_read(&space_info->groups_sem);
4906 if (list_empty(&block_group->list) ||
4909 * someone is removing this block group,
4910 * we can't jump into the have_block_group
4911 * target because our list pointers are not
4914 btrfs_put_block_group(block_group);
4915 up_read(&space_info->groups_sem);
4917 index = get_block_group_index(block_group);
4918 goto have_block_group;
4920 } else if (block_group) {
4921 btrfs_put_block_group(block_group);
4925 down_read(&space_info->groups_sem);
4926 list_for_each_entry(block_group, &space_info->block_groups[index],
4931 btrfs_get_block_group(block_group);
4932 search_start = block_group->key.objectid;
4935 if (unlikely(block_group->cached == BTRFS_CACHE_NO)) {
4938 ret = cache_block_group(block_group, trans, 1);
4939 if (block_group->cached == BTRFS_CACHE_FINISHED)
4940 goto have_block_group;
4942 free_percent = btrfs_block_group_used(&block_group->item);
4943 free_percent *= 100;
4944 free_percent = div64_u64(free_percent,
4945 block_group->key.offset);
4946 free_percent = 100 - free_percent;
4947 if (free_percent > ideal_cache_percent &&
4948 likely(!block_group->ro)) {
4949 ideal_cache_offset = block_group->key.objectid;
4950 ideal_cache_percent = free_percent;
4954 * We only want to start kthread caching if we are at
4955 * the point where we will wait for caching to make
4956 * progress, or if our ideal search is over and we've
4957 * found somebody to start caching.
4959 if (loop > LOOP_CACHING_NOWAIT ||
4960 (loop > LOOP_FIND_IDEAL &&
4961 atomic_read(&space_info->caching_threads) < 2)) {
4962 ret = cache_block_group(block_group, trans, 0);
4965 found_uncached_bg = true;
4968 * If loop is set for cached only, try the next block
4971 if (loop == LOOP_FIND_IDEAL)
4975 cached = block_group_cache_done(block_group);
4976 if (unlikely(!cached))
4977 found_uncached_bg = true;
4979 if (unlikely(block_group->ro))
4983 * Ok we want to try and use the cluster allocator, so lets look
4984 * there, unless we are on LOOP_NO_EMPTY_SIZE, since we will
4985 * have tried the cluster allocator plenty of times at this
4986 * point and not have found anything, so we are likely way too
4987 * fragmented for the clustering stuff to find anything, so lets
4988 * just skip it and let the allocator find whatever block it can
4991 if (last_ptr && loop < LOOP_NO_EMPTY_SIZE) {
4993 * the refill lock keeps out other
4994 * people trying to start a new cluster
4996 spin_lock(&last_ptr->refill_lock);
4997 if (last_ptr->block_group &&
4998 (last_ptr->block_group->ro ||
4999 !block_group_bits(last_ptr->block_group, data))) {
5001 goto refill_cluster;
5004 offset = btrfs_alloc_from_cluster(block_group, last_ptr,
5005 num_bytes, search_start);
5007 /* we have a block, we're done */
5008 spin_unlock(&last_ptr->refill_lock);
5012 spin_lock(&last_ptr->lock);
5014 * whoops, this cluster doesn't actually point to
5015 * this block group. Get a ref on the block
5016 * group is does point to and try again
5018 if (!last_ptr_loop && last_ptr->block_group &&
5019 last_ptr->block_group != block_group) {
5021 btrfs_put_block_group(block_group);
5022 block_group = last_ptr->block_group;
5023 btrfs_get_block_group(block_group);
5024 spin_unlock(&last_ptr->lock);
5025 spin_unlock(&last_ptr->refill_lock);
5028 search_start = block_group->key.objectid;
5030 * we know this block group is properly
5031 * in the list because
5032 * btrfs_remove_block_group, drops the
5033 * cluster before it removes the block
5034 * group from the list
5036 goto have_block_group;
5038 spin_unlock(&last_ptr->lock);
5041 * this cluster didn't work out, free it and
5044 btrfs_return_cluster_to_free_space(NULL, last_ptr);
5048 /* allocate a cluster in this block group */
5049 ret = btrfs_find_space_cluster(trans, root,
5050 block_group, last_ptr,
5052 empty_cluster + empty_size);
5055 * now pull our allocation out of this
5058 offset = btrfs_alloc_from_cluster(block_group,
5059 last_ptr, num_bytes,
5062 /* we found one, proceed */
5063 spin_unlock(&last_ptr->refill_lock);
5066 } else if (!cached && loop > LOOP_CACHING_NOWAIT
5067 && !failed_cluster_refill) {
5068 spin_unlock(&last_ptr->refill_lock);
5070 failed_cluster_refill = true;
5071 wait_block_group_cache_progress(block_group,
5072 num_bytes + empty_cluster + empty_size);
5073 goto have_block_group;
5077 * at this point we either didn't find a cluster
5078 * or we weren't able to allocate a block from our
5079 * cluster. Free the cluster we've been trying
5080 * to use, and go to the next block group
5082 btrfs_return_cluster_to_free_space(NULL, last_ptr);
5083 spin_unlock(&last_ptr->refill_lock);
5087 offset = btrfs_find_space_for_alloc(block_group, search_start,
5088 num_bytes, empty_size);
5090 * If we didn't find a chunk, and we haven't failed on this
5091 * block group before, and this block group is in the middle of
5092 * caching and we are ok with waiting, then go ahead and wait
5093 * for progress to be made, and set failed_alloc to true.
5095 * If failed_alloc is true then we've already waited on this
5096 * block group once and should move on to the next block group.
5098 if (!offset && !failed_alloc && !cached &&
5099 loop > LOOP_CACHING_NOWAIT) {
5100 wait_block_group_cache_progress(block_group,
5101 num_bytes + empty_size);
5102 failed_alloc = true;
5103 goto have_block_group;
5104 } else if (!offset) {
5108 search_start = stripe_align(root, offset);
5109 /* move on to the next group */
5110 if (search_start + num_bytes >= search_end) {
5111 btrfs_add_free_space(block_group, offset, num_bytes);
5115 /* move on to the next group */
5116 if (search_start + num_bytes >
5117 block_group->key.objectid + block_group->key.offset) {
5118 btrfs_add_free_space(block_group, offset, num_bytes);
5122 ins->objectid = search_start;
5123 ins->offset = num_bytes;
5125 if (offset < search_start)
5126 btrfs_add_free_space(block_group, offset,
5127 search_start - offset);
5128 BUG_ON(offset > search_start);
5130 ret = update_reserved_bytes(block_group, num_bytes, 1,
5131 (data & BTRFS_BLOCK_GROUP_DATA));
5132 if (ret == -EAGAIN) {
5133 btrfs_add_free_space(block_group, offset, num_bytes);
5137 /* we are all good, lets return */
5138 ins->objectid = search_start;
5139 ins->offset = num_bytes;
5141 if (offset < search_start)
5142 btrfs_add_free_space(block_group, offset,
5143 search_start - offset);
5144 BUG_ON(offset > search_start);
5147 failed_cluster_refill = false;
5148 failed_alloc = false;
5149 BUG_ON(index != get_block_group_index(block_group));
5150 btrfs_put_block_group(block_group);
5152 up_read(&space_info->groups_sem);
5154 if (!ins->objectid && ++index < BTRFS_NR_RAID_TYPES)
5157 /* LOOP_FIND_IDEAL, only search caching/cached bg's, and don't wait for
5158 * for them to make caching progress. Also
5159 * determine the best possible bg to cache
5160 * LOOP_CACHING_NOWAIT, search partially cached block groups, kicking
5161 * caching kthreads as we move along
5162 * LOOP_CACHING_WAIT, search everything, and wait if our bg is caching
5163 * LOOP_ALLOC_CHUNK, force a chunk allocation and try again
5164 * LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try
5167 if (!ins->objectid && loop < LOOP_NO_EMPTY_SIZE &&
5168 (found_uncached_bg || empty_size || empty_cluster ||
5169 allowed_chunk_alloc)) {
5171 if (loop == LOOP_FIND_IDEAL && found_uncached_bg) {
5172 found_uncached_bg = false;
5174 if (!ideal_cache_percent &&
5175 atomic_read(&space_info->caching_threads))
5179 * 1 of the following 2 things have happened so far
5181 * 1) We found an ideal block group for caching that
5182 * is mostly full and will cache quickly, so we might
5183 * as well wait for it.
5185 * 2) We searched for cached only and we didn't find
5186 * anything, and we didn't start any caching kthreads
5187 * either, so chances are we will loop through and
5188 * start a couple caching kthreads, and then come back
5189 * around and just wait for them. This will be slower
5190 * because we will have 2 caching kthreads reading at
5191 * the same time when we could have just started one
5192 * and waited for it to get far enough to give us an
5193 * allocation, so go ahead and go to the wait caching
5196 loop = LOOP_CACHING_WAIT;
5197 search_start = ideal_cache_offset;
5198 ideal_cache_percent = 0;
5200 } else if (loop == LOOP_FIND_IDEAL) {
5202 * Didn't find a uncached bg, wait on anything we find
5205 loop = LOOP_CACHING_WAIT;
5209 if (loop < LOOP_CACHING_WAIT) {
5214 if (loop == LOOP_ALLOC_CHUNK) {
5219 if (allowed_chunk_alloc) {
5220 ret = do_chunk_alloc(trans, root, num_bytes +
5221 2 * 1024 * 1024, data, 1);
5222 allowed_chunk_alloc = 0;
5223 done_chunk_alloc = 1;
5224 } else if (!done_chunk_alloc) {
5225 space_info->force_alloc = 1;
5228 if (loop < LOOP_NO_EMPTY_SIZE) {
5233 } else if (!ins->objectid) {
5237 /* we found what we needed */
5238 if (ins->objectid) {
5239 if (!(data & BTRFS_BLOCK_GROUP_DATA))
5240 trans->block_group = block_group->key.objectid;
5242 btrfs_put_block_group(block_group);
5249 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
5250 int dump_block_groups)
5252 struct btrfs_block_group_cache *cache;
5255 spin_lock(&info->lock);
5256 printk(KERN_INFO "space_info has %llu free, is %sfull\n",
5257 (unsigned long long)(info->total_bytes - info->bytes_used -
5258 info->bytes_pinned - info->bytes_reserved -
5259 info->bytes_readonly),
5260 (info->full) ? "" : "not ");
5261 printk(KERN_INFO "space_info total=%llu, used=%llu, pinned=%llu, "
5262 "reserved=%llu, may_use=%llu, readonly=%llu\n",
5263 (unsigned long long)info->total_bytes,
5264 (unsigned long long)info->bytes_used,
5265 (unsigned long long)info->bytes_pinned,
5266 (unsigned long long)info->bytes_reserved,
5267 (unsigned long long)info->bytes_may_use,
5268 (unsigned long long)info->bytes_readonly);
5269 spin_unlock(&info->lock);
5271 if (!dump_block_groups)
5274 down_read(&info->groups_sem);
5276 list_for_each_entry(cache, &info->block_groups[index], list) {
5277 spin_lock(&cache->lock);
5278 printk(KERN_INFO "block group %llu has %llu bytes, %llu used "
5279 "%llu pinned %llu reserved\n",
5280 (unsigned long long)cache->key.objectid,
5281 (unsigned long long)cache->key.offset,
5282 (unsigned long long)btrfs_block_group_used(&cache->item),
5283 (unsigned long long)cache->pinned,
5284 (unsigned long long)cache->reserved);
5285 btrfs_dump_free_space(cache, bytes);
5286 spin_unlock(&cache->lock);
5288 if (++index < BTRFS_NR_RAID_TYPES)
5290 up_read(&info->groups_sem);
5293 int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
5294 struct btrfs_root *root,
5295 u64 num_bytes, u64 min_alloc_size,
5296 u64 empty_size, u64 hint_byte,
5297 u64 search_end, struct btrfs_key *ins,
5301 u64 search_start = 0;
5303 data = btrfs_get_alloc_profile(root, data);
5306 * the only place that sets empty_size is btrfs_realloc_node, which
5307 * is not called recursively on allocations
5309 if (empty_size || root->ref_cows)
5310 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
5311 num_bytes + 2 * 1024 * 1024, data, 0);
5313 WARN_ON(num_bytes < root->sectorsize);
5314 ret = find_free_extent(trans, root, num_bytes, empty_size,
5315 search_start, search_end, hint_byte,
5318 if (ret == -ENOSPC && num_bytes > min_alloc_size) {
5319 num_bytes = num_bytes >> 1;
5320 num_bytes = num_bytes & ~(root->sectorsize - 1);
5321 num_bytes = max(num_bytes, min_alloc_size);
5322 do_chunk_alloc(trans, root->fs_info->extent_root,
5323 num_bytes, data, 1);
5326 if (ret == -ENOSPC) {
5327 struct btrfs_space_info *sinfo;
5329 sinfo = __find_space_info(root->fs_info, data);
5330 printk(KERN_ERR "btrfs allocation failed flags %llu, "
5331 "wanted %llu\n", (unsigned long long)data,
5332 (unsigned long long)num_bytes);
5333 dump_space_info(sinfo, num_bytes, 1);
5339 int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len)
5341 struct btrfs_block_group_cache *cache;
5344 cache = btrfs_lookup_block_group(root->fs_info, start);
5346 printk(KERN_ERR "Unable to find block group for %llu\n",
5347 (unsigned long long)start);
5351 ret = btrfs_discard_extent(root, start, len);
5353 btrfs_add_free_space(cache, start, len);
5354 update_reserved_bytes(cache, len, 0, 1);
5355 btrfs_put_block_group(cache);
5360 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
5361 struct btrfs_root *root,
5362 u64 parent, u64 root_objectid,
5363 u64 flags, u64 owner, u64 offset,
5364 struct btrfs_key *ins, int ref_mod)
5367 struct btrfs_fs_info *fs_info = root->fs_info;
5368 struct btrfs_extent_item *extent_item;
5369 struct btrfs_extent_inline_ref *iref;
5370 struct btrfs_path *path;
5371 struct extent_buffer *leaf;
5376 type = BTRFS_SHARED_DATA_REF_KEY;
5378 type = BTRFS_EXTENT_DATA_REF_KEY;
5380 size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type);
5382 path = btrfs_alloc_path();
5385 path->leave_spinning = 1;
5386 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
5390 leaf = path->nodes[0];
5391 extent_item = btrfs_item_ptr(leaf, path->slots[0],
5392 struct btrfs_extent_item);
5393 btrfs_set_extent_refs(leaf, extent_item, ref_mod);
5394 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
5395 btrfs_set_extent_flags(leaf, extent_item,
5396 flags | BTRFS_EXTENT_FLAG_DATA);
5398 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
5399 btrfs_set_extent_inline_ref_type(leaf, iref, type);
5401 struct btrfs_shared_data_ref *ref;
5402 ref = (struct btrfs_shared_data_ref *)(iref + 1);
5403 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
5404 btrfs_set_shared_data_ref_count(leaf, ref, ref_mod);
5406 struct btrfs_extent_data_ref *ref;
5407 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
5408 btrfs_set_extent_data_ref_root(leaf, ref, root_objectid);
5409 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
5410 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
5411 btrfs_set_extent_data_ref_count(leaf, ref, ref_mod);
5414 btrfs_mark_buffer_dirty(path->nodes[0]);
5415 btrfs_free_path(path);
5417 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
5419 printk(KERN_ERR "btrfs update block group failed for %llu "
5420 "%llu\n", (unsigned long long)ins->objectid,
5421 (unsigned long long)ins->offset);
5427 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
5428 struct btrfs_root *root,
5429 u64 parent, u64 root_objectid,
5430 u64 flags, struct btrfs_disk_key *key,
5431 int level, struct btrfs_key *ins)
5434 struct btrfs_fs_info *fs_info = root->fs_info;
5435 struct btrfs_extent_item *extent_item;
5436 struct btrfs_tree_block_info *block_info;
5437 struct btrfs_extent_inline_ref *iref;
5438 struct btrfs_path *path;
5439 struct extent_buffer *leaf;
5440 u32 size = sizeof(*extent_item) + sizeof(*block_info) + sizeof(*iref);
5442 path = btrfs_alloc_path();
5445 path->leave_spinning = 1;
5446 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
5450 leaf = path->nodes[0];
5451 extent_item = btrfs_item_ptr(leaf, path->slots[0],
5452 struct btrfs_extent_item);
5453 btrfs_set_extent_refs(leaf, extent_item, 1);
5454 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
5455 btrfs_set_extent_flags(leaf, extent_item,
5456 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
5457 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
5459 btrfs_set_tree_block_key(leaf, block_info, key);
5460 btrfs_set_tree_block_level(leaf, block_info, level);
5462 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
5464 BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF));
5465 btrfs_set_extent_inline_ref_type(leaf, iref,
5466 BTRFS_SHARED_BLOCK_REF_KEY);
5467 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
5469 btrfs_set_extent_inline_ref_type(leaf, iref,
5470 BTRFS_TREE_BLOCK_REF_KEY);
5471 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
5474 btrfs_mark_buffer_dirty(leaf);
5475 btrfs_free_path(path);
5477 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
5479 printk(KERN_ERR "btrfs update block group failed for %llu "
5480 "%llu\n", (unsigned long long)ins->objectid,
5481 (unsigned long long)ins->offset);
5487 int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
5488 struct btrfs_root *root,
5489 u64 root_objectid, u64 owner,
5490 u64 offset, struct btrfs_key *ins)
5494 BUG_ON(root_objectid == BTRFS_TREE_LOG_OBJECTID);
5496 ret = btrfs_add_delayed_data_ref(trans, ins->objectid, ins->offset,
5497 0, root_objectid, owner, offset,
5498 BTRFS_ADD_DELAYED_EXTENT, NULL);
5503 * this is used by the tree logging recovery code. It records that
5504 * an extent has been allocated and makes sure to clear the free
5505 * space cache bits as well
5507 int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
5508 struct btrfs_root *root,
5509 u64 root_objectid, u64 owner, u64 offset,
5510 struct btrfs_key *ins)
5513 struct btrfs_block_group_cache *block_group;
5514 struct btrfs_caching_control *caching_ctl;
5515 u64 start = ins->objectid;
5516 u64 num_bytes = ins->offset;
5518 block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
5519 cache_block_group(block_group, trans, 0);
5520 caching_ctl = get_caching_control(block_group);
5523 BUG_ON(!block_group_cache_done(block_group));
5524 ret = btrfs_remove_free_space(block_group, start, num_bytes);
5527 mutex_lock(&caching_ctl->mutex);
5529 if (start >= caching_ctl->progress) {
5530 ret = add_excluded_extent(root, start, num_bytes);
5532 } else if (start + num_bytes <= caching_ctl->progress) {
5533 ret = btrfs_remove_free_space(block_group,
5537 num_bytes = caching_ctl->progress - start;
5538 ret = btrfs_remove_free_space(block_group,
5542 start = caching_ctl->progress;
5543 num_bytes = ins->objectid + ins->offset -
5544 caching_ctl->progress;
5545 ret = add_excluded_extent(root, start, num_bytes);
5549 mutex_unlock(&caching_ctl->mutex);
5550 put_caching_control(caching_ctl);
5553 ret = update_reserved_bytes(block_group, ins->offset, 1, 1);
5555 btrfs_put_block_group(block_group);
5556 ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,
5557 0, owner, offset, ins, 1);
5561 struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
5562 struct btrfs_root *root,
5563 u64 bytenr, u32 blocksize,
5566 struct extent_buffer *buf;
5568 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
5570 return ERR_PTR(-ENOMEM);
5571 btrfs_set_header_generation(buf, trans->transid);
5572 btrfs_set_buffer_lockdep_class(buf, level);
5573 btrfs_tree_lock(buf);
5574 clean_tree_block(trans, root, buf);
5576 btrfs_set_lock_blocking(buf);
5577 btrfs_set_buffer_uptodate(buf);
5579 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
5581 * we allow two log transactions at a time, use different
5582 * EXENT bit to differentiate dirty pages.
5584 if (root->log_transid % 2 == 0)
5585 set_extent_dirty(&root->dirty_log_pages, buf->start,
5586 buf->start + buf->len - 1, GFP_NOFS);
5588 set_extent_new(&root->dirty_log_pages, buf->start,
5589 buf->start + buf->len - 1, GFP_NOFS);
5591 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
5592 buf->start + buf->len - 1, GFP_NOFS);
5594 trans->blocks_used++;
5595 /* this returns a buffer locked for blocking */
5599 static struct btrfs_block_rsv *
5600 use_block_rsv(struct btrfs_trans_handle *trans,
5601 struct btrfs_root *root, u32 blocksize)
5603 struct btrfs_block_rsv *block_rsv;
5606 block_rsv = get_block_rsv(trans, root);
5608 if (block_rsv->size == 0) {
5609 ret = reserve_metadata_bytes(trans, root, block_rsv,
5612 return ERR_PTR(ret);
5616 ret = block_rsv_use_bytes(block_rsv, blocksize);
5620 return ERR_PTR(-ENOSPC);
5623 static void unuse_block_rsv(struct btrfs_block_rsv *block_rsv, u32 blocksize)
5625 block_rsv_add_bytes(block_rsv, blocksize, 0);
5626 block_rsv_release_bytes(block_rsv, NULL, 0);
5630 * finds a free extent and does all the dirty work required for allocation
5631 * returns the key for the extent through ins, and a tree buffer for
5632 * the first block of the extent through buf.
5634 * returns the tree buffer or NULL.
5636 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
5637 struct btrfs_root *root, u32 blocksize,
5638 u64 parent, u64 root_objectid,
5639 struct btrfs_disk_key *key, int level,
5640 u64 hint, u64 empty_size)
5642 struct btrfs_key ins;
5643 struct btrfs_block_rsv *block_rsv;
5644 struct extent_buffer *buf;
5649 block_rsv = use_block_rsv(trans, root, blocksize);
5650 if (IS_ERR(block_rsv))
5651 return ERR_CAST(block_rsv);
5653 ret = btrfs_reserve_extent(trans, root, blocksize, blocksize,
5654 empty_size, hint, (u64)-1, &ins, 0);
5656 unuse_block_rsv(block_rsv, blocksize);
5657 return ERR_PTR(ret);
5660 buf = btrfs_init_new_buffer(trans, root, ins.objectid,
5662 BUG_ON(IS_ERR(buf));
5664 if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
5666 parent = ins.objectid;
5667 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
5671 if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
5672 struct btrfs_delayed_extent_op *extent_op;
5673 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
5676 memcpy(&extent_op->key, key, sizeof(extent_op->key));
5678 memset(&extent_op->key, 0, sizeof(extent_op->key));
5679 extent_op->flags_to_set = flags;
5680 extent_op->update_key = 1;
5681 extent_op->update_flags = 1;
5682 extent_op->is_data = 0;
5684 ret = btrfs_add_delayed_tree_ref(trans, ins.objectid,
5685 ins.offset, parent, root_objectid,
5686 level, BTRFS_ADD_DELAYED_EXTENT,
5693 struct walk_control {
5694 u64 refs[BTRFS_MAX_LEVEL];
5695 u64 flags[BTRFS_MAX_LEVEL];
5696 struct btrfs_key update_progress;
5706 #define DROP_REFERENCE 1
5707 #define UPDATE_BACKREF 2
5709 static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
5710 struct btrfs_root *root,
5711 struct walk_control *wc,
5712 struct btrfs_path *path)
5720 struct btrfs_key key;
5721 struct extent_buffer *eb;
5726 if (path->slots[wc->level] < wc->reada_slot) {
5727 wc->reada_count = wc->reada_count * 2 / 3;
5728 wc->reada_count = max(wc->reada_count, 2);
5730 wc->reada_count = wc->reada_count * 3 / 2;
5731 wc->reada_count = min_t(int, wc->reada_count,
5732 BTRFS_NODEPTRS_PER_BLOCK(root));
5735 eb = path->nodes[wc->level];
5736 nritems = btrfs_header_nritems(eb);
5737 blocksize = btrfs_level_size(root, wc->level - 1);
5739 for (slot = path->slots[wc->level]; slot < nritems; slot++) {
5740 if (nread >= wc->reada_count)
5744 bytenr = btrfs_node_blockptr(eb, slot);
5745 generation = btrfs_node_ptr_generation(eb, slot);
5747 if (slot == path->slots[wc->level])
5750 if (wc->stage == UPDATE_BACKREF &&
5751 generation <= root->root_key.offset)
5754 /* We don't lock the tree block, it's OK to be racy here */
5755 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
5760 if (wc->stage == DROP_REFERENCE) {
5764 if (wc->level == 1 &&
5765 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5767 if (!wc->update_ref ||
5768 generation <= root->root_key.offset)
5770 btrfs_node_key_to_cpu(eb, &key, slot);
5771 ret = btrfs_comp_cpu_keys(&key,
5772 &wc->update_progress);
5776 if (wc->level == 1 &&
5777 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5781 ret = readahead_tree_block(root, bytenr, blocksize,
5787 wc->reada_slot = slot;
5791 * hepler to process tree block while walking down the tree.
5793 * when wc->stage == UPDATE_BACKREF, this function updates
5794 * back refs for pointers in the block.
5796 * NOTE: return value 1 means we should stop walking down.
5798 static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
5799 struct btrfs_root *root,
5800 struct btrfs_path *path,
5801 struct walk_control *wc, int lookup_info)
5803 int level = wc->level;
5804 struct extent_buffer *eb = path->nodes[level];
5805 u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF;
5808 if (wc->stage == UPDATE_BACKREF &&
5809 btrfs_header_owner(eb) != root->root_key.objectid)
5813 * when reference count of tree block is 1, it won't increase
5814 * again. once full backref flag is set, we never clear it.
5817 ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
5818 (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag)))) {
5819 BUG_ON(!path->locks[level]);
5820 ret = btrfs_lookup_extent_info(trans, root,
5825 BUG_ON(wc->refs[level] == 0);
5828 if (wc->stage == DROP_REFERENCE) {
5829 if (wc->refs[level] > 1)
5832 if (path->locks[level] && !wc->keep_locks) {
5833 btrfs_tree_unlock(eb);
5834 path->locks[level] = 0;
5839 /* wc->stage == UPDATE_BACKREF */
5840 if (!(wc->flags[level] & flag)) {
5841 BUG_ON(!path->locks[level]);
5842 ret = btrfs_inc_ref(trans, root, eb, 1);
5844 ret = btrfs_dec_ref(trans, root, eb, 0);
5846 ret = btrfs_set_disk_extent_flags(trans, root, eb->start,
5849 wc->flags[level] |= flag;
5853 * the block is shared by multiple trees, so it's not good to
5854 * keep the tree lock
5856 if (path->locks[level] && level > 0) {
5857 btrfs_tree_unlock(eb);
5858 path->locks[level] = 0;
5864 * hepler to process tree block pointer.
5866 * when wc->stage == DROP_REFERENCE, this function checks
5867 * reference count of the block pointed to. if the block
5868 * is shared and we need update back refs for the subtree
5869 * rooted at the block, this function changes wc->stage to
5870 * UPDATE_BACKREF. if the block is shared and there is no
5871 * need to update back, this function drops the reference
5874 * NOTE: return value 1 means we should stop walking down.
5876 static noinline int do_walk_down(struct btrfs_trans_handle *trans,
5877 struct btrfs_root *root,
5878 struct btrfs_path *path,
5879 struct walk_control *wc, int *lookup_info)
5885 struct btrfs_key key;
5886 struct extent_buffer *next;
5887 int level = wc->level;
5891 generation = btrfs_node_ptr_generation(path->nodes[level],
5892 path->slots[level]);
5894 * if the lower level block was created before the snapshot
5895 * was created, we know there is no need to update back refs
5898 if (wc->stage == UPDATE_BACKREF &&
5899 generation <= root->root_key.offset) {
5904 bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]);
5905 blocksize = btrfs_level_size(root, level - 1);
5907 next = btrfs_find_tree_block(root, bytenr, blocksize);
5909 next = btrfs_find_create_tree_block(root, bytenr, blocksize);
5914 btrfs_tree_lock(next);
5915 btrfs_set_lock_blocking(next);
5917 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
5918 &wc->refs[level - 1],
5919 &wc->flags[level - 1]);
5921 BUG_ON(wc->refs[level - 1] == 0);
5924 if (wc->stage == DROP_REFERENCE) {
5925 if (wc->refs[level - 1] > 1) {
5927 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5930 if (!wc->update_ref ||
5931 generation <= root->root_key.offset)
5934 btrfs_node_key_to_cpu(path->nodes[level], &key,
5935 path->slots[level]);
5936 ret = btrfs_comp_cpu_keys(&key, &wc->update_progress);
5940 wc->stage = UPDATE_BACKREF;
5941 wc->shared_level = level - 1;
5945 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5949 if (!btrfs_buffer_uptodate(next, generation)) {
5950 btrfs_tree_unlock(next);
5951 free_extent_buffer(next);
5957 if (reada && level == 1)
5958 reada_walk_down(trans, root, wc, path);
5959 next = read_tree_block(root, bytenr, blocksize, generation);
5960 btrfs_tree_lock(next);
5961 btrfs_set_lock_blocking(next);
5965 BUG_ON(level != btrfs_header_level(next));
5966 path->nodes[level] = next;
5967 path->slots[level] = 0;
5968 path->locks[level] = 1;
5974 wc->refs[level - 1] = 0;
5975 wc->flags[level - 1] = 0;
5976 if (wc->stage == DROP_REFERENCE) {
5977 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
5978 parent = path->nodes[level]->start;
5980 BUG_ON(root->root_key.objectid !=
5981 btrfs_header_owner(path->nodes[level]));
5985 ret = btrfs_free_extent(trans, root, bytenr, blocksize, parent,
5986 root->root_key.objectid, level - 1, 0);
5989 btrfs_tree_unlock(next);
5990 free_extent_buffer(next);
5996 * hepler to process tree block while walking up the tree.
5998 * when wc->stage == DROP_REFERENCE, this function drops
5999 * reference count on the block.
6001 * when wc->stage == UPDATE_BACKREF, this function changes
6002 * wc->stage back to DROP_REFERENCE if we changed wc->stage
6003 * to UPDATE_BACKREF previously while processing the block.
6005 * NOTE: return value 1 means we should stop walking up.
6007 static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
6008 struct btrfs_root *root,
6009 struct btrfs_path *path,
6010 struct walk_control *wc)
6013 int level = wc->level;
6014 struct extent_buffer *eb = path->nodes[level];
6017 if (wc->stage == UPDATE_BACKREF) {
6018 BUG_ON(wc->shared_level < level);
6019 if (level < wc->shared_level)
6022 ret = find_next_key(path, level + 1, &wc->update_progress);
6026 wc->stage = DROP_REFERENCE;
6027 wc->shared_level = -1;
6028 path->slots[level] = 0;
6031 * check reference count again if the block isn't locked.
6032 * we should start walking down the tree again if reference
6035 if (!path->locks[level]) {
6037 btrfs_tree_lock(eb);
6038 btrfs_set_lock_blocking(eb);
6039 path->locks[level] = 1;
6041 ret = btrfs_lookup_extent_info(trans, root,
6046 BUG_ON(wc->refs[level] == 0);
6047 if (wc->refs[level] == 1) {
6048 btrfs_tree_unlock(eb);
6049 path->locks[level] = 0;
6055 /* wc->stage == DROP_REFERENCE */
6056 BUG_ON(wc->refs[level] > 1 && !path->locks[level]);
6058 if (wc->refs[level] == 1) {
6060 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6061 ret = btrfs_dec_ref(trans, root, eb, 1);
6063 ret = btrfs_dec_ref(trans, root, eb, 0);
6066 /* make block locked assertion in clean_tree_block happy */
6067 if (!path->locks[level] &&
6068 btrfs_header_generation(eb) == trans->transid) {
6069 btrfs_tree_lock(eb);
6070 btrfs_set_lock_blocking(eb);
6071 path->locks[level] = 1;
6073 clean_tree_block(trans, root, eb);
6076 if (eb == root->node) {
6077 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6080 BUG_ON(root->root_key.objectid !=
6081 btrfs_header_owner(eb));
6083 if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6084 parent = path->nodes[level + 1]->start;
6086 BUG_ON(root->root_key.objectid !=
6087 btrfs_header_owner(path->nodes[level + 1]));
6090 btrfs_free_tree_block(trans, root, eb, parent, wc->refs[level] == 1);
6092 wc->refs[level] = 0;
6093 wc->flags[level] = 0;
6097 static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
6098 struct btrfs_root *root,
6099 struct btrfs_path *path,
6100 struct walk_control *wc)
6102 int level = wc->level;
6103 int lookup_info = 1;
6106 while (level >= 0) {
6107 ret = walk_down_proc(trans, root, path, wc, lookup_info);
6114 if (path->slots[level] >=
6115 btrfs_header_nritems(path->nodes[level]))
6118 ret = do_walk_down(trans, root, path, wc, &lookup_info);
6120 path->slots[level]++;
6129 static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
6130 struct btrfs_root *root,
6131 struct btrfs_path *path,
6132 struct walk_control *wc, int max_level)
6134 int level = wc->level;
6137 path->slots[level] = btrfs_header_nritems(path->nodes[level]);
6138 while (level < max_level && path->nodes[level]) {
6140 if (path->slots[level] + 1 <
6141 btrfs_header_nritems(path->nodes[level])) {
6142 path->slots[level]++;
6145 ret = walk_up_proc(trans, root, path, wc);
6149 if (path->locks[level]) {
6150 btrfs_tree_unlock(path->nodes[level]);
6151 path->locks[level] = 0;
6153 free_extent_buffer(path->nodes[level]);
6154 path->nodes[level] = NULL;
6162 * drop a subvolume tree.
6164 * this function traverses the tree freeing any blocks that only
6165 * referenced by the tree.
6167 * when a shared tree block is found. this function decreases its
6168 * reference count by one. if update_ref is true, this function
6169 * also make sure backrefs for the shared block and all lower level
6170 * blocks are properly updated.
6172 int btrfs_drop_snapshot(struct btrfs_root *root,
6173 struct btrfs_block_rsv *block_rsv, int update_ref)
6175 struct btrfs_path *path;
6176 struct btrfs_trans_handle *trans;
6177 struct btrfs_root *tree_root = root->fs_info->tree_root;
6178 struct btrfs_root_item *root_item = &root->root_item;
6179 struct walk_control *wc;
6180 struct btrfs_key key;
6185 path = btrfs_alloc_path();
6188 wc = kzalloc(sizeof(*wc), GFP_NOFS);
6191 trans = btrfs_start_transaction(tree_root, 0);
6193 trans->block_rsv = block_rsv;
6195 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
6196 level = btrfs_header_level(root->node);
6197 path->nodes[level] = btrfs_lock_root_node(root);
6198 btrfs_set_lock_blocking(path->nodes[level]);
6199 path->slots[level] = 0;
6200 path->locks[level] = 1;
6201 memset(&wc->update_progress, 0,
6202 sizeof(wc->update_progress));
6204 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
6205 memcpy(&wc->update_progress, &key,
6206 sizeof(wc->update_progress));
6208 level = root_item->drop_level;
6210 path->lowest_level = level;
6211 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6212 path->lowest_level = 0;
6220 * unlock our path, this is safe because only this
6221 * function is allowed to delete this snapshot
6223 btrfs_unlock_up_safe(path, 0);
6225 level = btrfs_header_level(root->node);
6227 btrfs_tree_lock(path->nodes[level]);
6228 btrfs_set_lock_blocking(path->nodes[level]);
6230 ret = btrfs_lookup_extent_info(trans, root,
6231 path->nodes[level]->start,
6232 path->nodes[level]->len,
6236 BUG_ON(wc->refs[level] == 0);
6238 if (level == root_item->drop_level)
6241 btrfs_tree_unlock(path->nodes[level]);
6242 WARN_ON(wc->refs[level] != 1);
6248 wc->shared_level = -1;
6249 wc->stage = DROP_REFERENCE;
6250 wc->update_ref = update_ref;
6252 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
6255 ret = walk_down_tree(trans, root, path, wc);
6261 ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL);
6268 BUG_ON(wc->stage != DROP_REFERENCE);
6272 if (wc->stage == DROP_REFERENCE) {
6274 btrfs_node_key(path->nodes[level],
6275 &root_item->drop_progress,
6276 path->slots[level]);
6277 root_item->drop_level = level;
6280 BUG_ON(wc->level == 0);
6281 if (btrfs_should_end_transaction(trans, tree_root)) {
6282 ret = btrfs_update_root(trans, tree_root,
6287 btrfs_end_transaction_throttle(trans, tree_root);
6288 trans = btrfs_start_transaction(tree_root, 0);
6290 trans->block_rsv = block_rsv;
6293 btrfs_release_path(root, path);
6296 ret = btrfs_del_root(trans, tree_root, &root->root_key);
6299 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
6300 ret = btrfs_find_last_root(tree_root, root->root_key.objectid,
6304 ret = btrfs_del_orphan_item(trans, tree_root,
6305 root->root_key.objectid);
6310 if (root->in_radix) {
6311 btrfs_free_fs_root(tree_root->fs_info, root);
6313 free_extent_buffer(root->node);
6314 free_extent_buffer(root->commit_root);
6318 btrfs_end_transaction_throttle(trans, tree_root);
6320 btrfs_free_path(path);
6325 * drop subtree rooted at tree block 'node'.
6327 * NOTE: this function will unlock and release tree block 'node'
6329 int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
6330 struct btrfs_root *root,
6331 struct extent_buffer *node,
6332 struct extent_buffer *parent)
6334 struct btrfs_path *path;
6335 struct walk_control *wc;
6341 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
6343 path = btrfs_alloc_path();
6346 wc = kzalloc(sizeof(*wc), GFP_NOFS);
6349 btrfs_assert_tree_locked(parent);
6350 parent_level = btrfs_header_level(parent);
6351 extent_buffer_get(parent);
6352 path->nodes[parent_level] = parent;
6353 path->slots[parent_level] = btrfs_header_nritems(parent);
6355 btrfs_assert_tree_locked(node);
6356 level = btrfs_header_level(node);
6357 path->nodes[level] = node;
6358 path->slots[level] = 0;
6359 path->locks[level] = 1;
6361 wc->refs[parent_level] = 1;
6362 wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF;
6364 wc->shared_level = -1;
6365 wc->stage = DROP_REFERENCE;
6368 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
6371 wret = walk_down_tree(trans, root, path, wc);
6377 wret = walk_up_tree(trans, root, path, wc, parent_level);
6385 btrfs_free_path(path);
6390 static unsigned long calc_ra(unsigned long start, unsigned long last,
6393 return min(last, start + nr - 1);
6396 static noinline int relocate_inode_pages(struct inode *inode, u64 start,
6401 unsigned long first_index;
6402 unsigned long last_index;
6405 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
6406 struct file_ra_state *ra;
6407 struct btrfs_ordered_extent *ordered;
6408 unsigned int total_read = 0;
6409 unsigned int total_dirty = 0;
6412 ra = kzalloc(sizeof(*ra), GFP_NOFS);
6414 mutex_lock(&inode->i_mutex);
6415 first_index = start >> PAGE_CACHE_SHIFT;
6416 last_index = (start + len - 1) >> PAGE_CACHE_SHIFT;
6418 /* make sure the dirty trick played by the caller work */
6419 ret = invalidate_inode_pages2_range(inode->i_mapping,
6420 first_index, last_index);
6424 file_ra_state_init(ra, inode->i_mapping);
6426 for (i = first_index ; i <= last_index; i++) {
6427 if (total_read % ra->ra_pages == 0) {
6428 btrfs_force_ra(inode->i_mapping, ra, NULL, i,
6429 calc_ra(i, last_index, ra->ra_pages));
6433 if (((u64)i << PAGE_CACHE_SHIFT) > i_size_read(inode))
6435 page = grab_cache_page(inode->i_mapping, i);
6440 if (!PageUptodate(page)) {
6441 btrfs_readpage(NULL, page);
6443 if (!PageUptodate(page)) {
6445 page_cache_release(page);
6450 wait_on_page_writeback(page);
6452 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
6453 page_end = page_start + PAGE_CACHE_SIZE - 1;
6454 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
6456 ordered = btrfs_lookup_ordered_extent(inode, page_start);
6458 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
6460 page_cache_release(page);
6461 btrfs_start_ordered_extent(inode, ordered, 1);
6462 btrfs_put_ordered_extent(ordered);
6465 set_page_extent_mapped(page);
6467 if (i == first_index)
6468 set_extent_bits(io_tree, page_start, page_end,
6469 EXTENT_BOUNDARY, GFP_NOFS);
6470 btrfs_set_extent_delalloc(inode, page_start, page_end);
6472 set_page_dirty(page);
6475 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
6477 page_cache_release(page);
6482 mutex_unlock(&inode->i_mutex);
6483 balance_dirty_pages_ratelimited_nr(inode->i_mapping, total_dirty);
6487 static noinline int relocate_data_extent(struct inode *reloc_inode,
6488 struct btrfs_key *extent_key,
6491 struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
6492 struct extent_map_tree *em_tree = &BTRFS_I(reloc_inode)->extent_tree;
6493 struct extent_map *em;
6494 u64 start = extent_key->objectid - offset;
6495 u64 end = start + extent_key->offset - 1;
6497 em = alloc_extent_map(GFP_NOFS);
6498 BUG_ON(!em || IS_ERR(em));
6501 em->len = extent_key->offset;
6502 em->block_len = extent_key->offset;
6503 em->block_start = extent_key->objectid;
6504 em->bdev = root->fs_info->fs_devices->latest_bdev;
6505 set_bit(EXTENT_FLAG_PINNED, &em->flags);
6507 /* setup extent map to cheat btrfs_readpage */
6508 lock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
6511 write_lock(&em_tree->lock);
6512 ret = add_extent_mapping(em_tree, em);
6513 write_unlock(&em_tree->lock);
6514 if (ret != -EEXIST) {
6515 free_extent_map(em);
6518 btrfs_drop_extent_cache(reloc_inode, start, end, 0);
6520 unlock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
6522 return relocate_inode_pages(reloc_inode, start, extent_key->offset);
6525 struct btrfs_ref_path {
6527 u64 nodes[BTRFS_MAX_LEVEL];
6529 u64 root_generation;
6536 struct btrfs_key node_keys[BTRFS_MAX_LEVEL];
6537 u64 new_nodes[BTRFS_MAX_LEVEL];
6540 struct disk_extent {
6551 static int is_cowonly_root(u64 root_objectid)
6553 if (root_objectid == BTRFS_ROOT_TREE_OBJECTID ||
6554 root_objectid == BTRFS_EXTENT_TREE_OBJECTID ||
6555 root_objectid == BTRFS_CHUNK_TREE_OBJECTID ||
6556 root_objectid == BTRFS_DEV_TREE_OBJECTID ||
6557 root_objectid == BTRFS_TREE_LOG_OBJECTID ||
6558 root_objectid == BTRFS_CSUM_TREE_OBJECTID)
6563 static noinline int __next_ref_path(struct btrfs_trans_handle *trans,
6564 struct btrfs_root *extent_root,
6565 struct btrfs_ref_path *ref_path,
6568 struct extent_buffer *leaf;
6569 struct btrfs_path *path;
6570 struct btrfs_extent_ref *ref;
6571 struct btrfs_key key;
6572 struct btrfs_key found_key;
6578 path = btrfs_alloc_path();
6583 ref_path->lowest_level = -1;
6584 ref_path->current_level = -1;
6585 ref_path->shared_level = -1;
6589 level = ref_path->current_level - 1;
6590 while (level >= -1) {
6592 if (level < ref_path->lowest_level)
6596 bytenr = ref_path->nodes[level];
6598 bytenr = ref_path->extent_start;
6599 BUG_ON(bytenr == 0);
6601 parent = ref_path->nodes[level + 1];
6602 ref_path->nodes[level + 1] = 0;
6603 ref_path->current_level = level;
6604 BUG_ON(parent == 0);
6606 key.objectid = bytenr;
6607 key.offset = parent + 1;
6608 key.type = BTRFS_EXTENT_REF_KEY;
6610 ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0);
6615 leaf = path->nodes[0];
6616 nritems = btrfs_header_nritems(leaf);
6617 if (path->slots[0] >= nritems) {
6618 ret = btrfs_next_leaf(extent_root, path);
6623 leaf = path->nodes[0];
6626 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6627 if (found_key.objectid == bytenr &&
6628 found_key.type == BTRFS_EXTENT_REF_KEY) {
6629 if (level < ref_path->shared_level)
6630 ref_path->shared_level = level;
6635 btrfs_release_path(extent_root, path);
6638 /* reached lowest level */
6642 level = ref_path->current_level;
6643 while (level < BTRFS_MAX_LEVEL - 1) {
6647 bytenr = ref_path->nodes[level];
6649 bytenr = ref_path->extent_start;
6651 BUG_ON(bytenr == 0);
6653 key.objectid = bytenr;
6655 key.type = BTRFS_EXTENT_REF_KEY;
6657 ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0);
6661 leaf = path->nodes[0];
6662 nritems = btrfs_header_nritems(leaf);
6663 if (path->slots[0] >= nritems) {
6664 ret = btrfs_next_leaf(extent_root, path);
6668 /* the extent was freed by someone */
6669 if (ref_path->lowest_level == level)
6671 btrfs_release_path(extent_root, path);
6674 leaf = path->nodes[0];
6677 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6678 if (found_key.objectid != bytenr ||
6679 found_key.type != BTRFS_EXTENT_REF_KEY) {
6680 /* the extent was freed by someone */
6681 if (ref_path->lowest_level == level) {
6685 btrfs_release_path(extent_root, path);
6689 ref = btrfs_item_ptr(leaf, path->slots[0],
6690 struct btrfs_extent_ref);
6691 ref_objectid = btrfs_ref_objectid(leaf, ref);
6692 if (ref_objectid < BTRFS_FIRST_FREE_OBJECTID) {
6694 level = (int)ref_objectid;
6695 BUG_ON(level >= BTRFS_MAX_LEVEL);
6696 ref_path->lowest_level = level;
6697 ref_path->current_level = level;
6698 ref_path->nodes[level] = bytenr;
6700 WARN_ON(ref_objectid != level);
6703 WARN_ON(level != -1);
6707 if (ref_path->lowest_level == level) {
6708 ref_path->owner_objectid = ref_objectid;
6709 ref_path->num_refs = btrfs_ref_num_refs(leaf, ref);
6713 * the block is tree root or the block isn't in reference
6716 if (found_key.objectid == found_key.offset ||
6717 is_cowonly_root(btrfs_ref_root(leaf, ref))) {
6718 ref_path->root_objectid = btrfs_ref_root(leaf, ref);
6719 ref_path->root_generation =
6720 btrfs_ref_generation(leaf, ref);
6722 /* special reference from the tree log */
6723 ref_path->nodes[0] = found_key.offset;
6724 ref_path->current_level = 0;
6731 BUG_ON(ref_path->nodes[level] != 0);
6732 ref_path->nodes[level] = found_key.offset;
6733 ref_path->current_level = level;
6736 * the reference was created in the running transaction,
6737 * no need to continue walking up.
6739 if (btrfs_ref_generation(leaf, ref) == trans->transid) {
6740 ref_path->root_objectid = btrfs_ref_root(leaf, ref);
6741 ref_path->root_generation =
6742 btrfs_ref_generation(leaf, ref);
6747 btrfs_release_path(extent_root, path);
6750 /* reached max tree level, but no tree root found. */
6753 btrfs_free_path(path);
6757 static int btrfs_first_ref_path(struct btrfs_trans_handle *trans,
6758 struct btrfs_root *extent_root,
6759 struct btrfs_ref_path *ref_path,
6762 memset(ref_path, 0, sizeof(*ref_path));
6763 ref_path->extent_start = extent_start;
6765 return __next_ref_path(trans, extent_root, ref_path, 1);
6768 static int btrfs_next_ref_path(struct btrfs_trans_handle *trans,
6769 struct btrfs_root *extent_root,
6770 struct btrfs_ref_path *ref_path)
6772 return __next_ref_path(trans, extent_root, ref_path, 0);
6775 static noinline int get_new_locations(struct inode *reloc_inode,
6776 struct btrfs_key *extent_key,
6777 u64 offset, int no_fragment,
6778 struct disk_extent **extents,
6781 struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
6782 struct btrfs_path *path;
6783 struct btrfs_file_extent_item *fi;
6784 struct extent_buffer *leaf;
6785 struct disk_extent *exts = *extents;
6786 struct btrfs_key found_key;
6791 int max = *nr_extents;
6794 WARN_ON(!no_fragment && *extents);
6797 exts = kmalloc(sizeof(*exts) * max, GFP_NOFS);
6802 path = btrfs_alloc_path();
6805 cur_pos = extent_key->objectid - offset;
6806 last_byte = extent_key->objectid + extent_key->offset;
6807 ret = btrfs_lookup_file_extent(NULL, root, path, reloc_inode->i_ino,
6817 leaf = path->nodes[0];
6818 nritems = btrfs_header_nritems(leaf);
6819 if (path->slots[0] >= nritems) {
6820 ret = btrfs_next_leaf(root, path);
6825 leaf = path->nodes[0];
6828 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6829 if (found_key.offset != cur_pos ||
6830 found_key.type != BTRFS_EXTENT_DATA_KEY ||
6831 found_key.objectid != reloc_inode->i_ino)
6834 fi = btrfs_item_ptr(leaf, path->slots[0],
6835 struct btrfs_file_extent_item);
6836 if (btrfs_file_extent_type(leaf, fi) !=
6837 BTRFS_FILE_EXTENT_REG ||
6838 btrfs_file_extent_disk_bytenr(leaf, fi) == 0)
6842 struct disk_extent *old = exts;
6844 exts = kzalloc(sizeof(*exts) * max, GFP_NOFS);
6845 memcpy(exts, old, sizeof(*exts) * nr);
6846 if (old != *extents)
6850 exts[nr].disk_bytenr =
6851 btrfs_file_extent_disk_bytenr(leaf, fi);
6852 exts[nr].disk_num_bytes =
6853 btrfs_file_extent_disk_num_bytes(leaf, fi);
6854 exts[nr].offset = btrfs_file_extent_offset(leaf, fi);
6855 exts[nr].num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
6856 exts[nr].ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
6857 exts[nr].compression = btrfs_file_extent_compression(leaf, fi);
6858 exts[nr].encryption = btrfs_file_extent_encryption(leaf, fi);
6859 exts[nr].other_encoding = btrfs_file_extent_other_encoding(leaf,
6861 BUG_ON(exts[nr].offset > 0);
6862 BUG_ON(exts[nr].compression || exts[nr].encryption);
6863 BUG_ON(exts[nr].num_bytes != exts[nr].disk_num_bytes);
6865 cur_pos += exts[nr].num_bytes;
6868 if (cur_pos + offset >= last_byte)
6878 BUG_ON(cur_pos + offset > last_byte);
6879 if (cur_pos + offset < last_byte) {
6885 btrfs_free_path(path);
6887 if (exts != *extents)
6896 static noinline int replace_one_extent(struct btrfs_trans_handle *trans,
6897 struct btrfs_root *root,
6898 struct btrfs_path *path,
6899 struct btrfs_key *extent_key,
6900 struct btrfs_key *leaf_key,
6901 struct btrfs_ref_path *ref_path,
6902 struct disk_extent *new_extents,
6905 struct extent_buffer *leaf;
6906 struct btrfs_file_extent_item *fi;
6907 struct inode *inode = NULL;
6908 struct btrfs_key key;
6913 u64 search_end = (u64)-1;
6916 int extent_locked = 0;
6920 memcpy(&key, leaf_key, sizeof(key));
6921 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) {
6922 if (key.objectid < ref_path->owner_objectid ||
6923 (key.objectid == ref_path->owner_objectid &&
6924 key.type < BTRFS_EXTENT_DATA_KEY)) {
6925 key.objectid = ref_path->owner_objectid;
6926 key.type = BTRFS_EXTENT_DATA_KEY;
6932 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
6936 leaf = path->nodes[0];
6937 nritems = btrfs_header_nritems(leaf);
6939 if (extent_locked && ret > 0) {
6941 * the file extent item was modified by someone
6942 * before the extent got locked.
6944 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
6945 lock_end, GFP_NOFS);
6949 if (path->slots[0] >= nritems) {
6950 if (++nr_scaned > 2)
6953 BUG_ON(extent_locked);
6954 ret = btrfs_next_leaf(root, path);
6959 leaf = path->nodes[0];
6960 nritems = btrfs_header_nritems(leaf);
6963 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
6965 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) {
6966 if ((key.objectid > ref_path->owner_objectid) ||
6967 (key.objectid == ref_path->owner_objectid &&
6968 key.type > BTRFS_EXTENT_DATA_KEY) ||
6969 key.offset >= search_end)
6973 if (inode && key.objectid != inode->i_ino) {
6974 BUG_ON(extent_locked);
6975 btrfs_release_path(root, path);
6976 mutex_unlock(&inode->i_mutex);
6982 if (key.type != BTRFS_EXTENT_DATA_KEY) {
6987 fi = btrfs_item_ptr(leaf, path->slots[0],
6988 struct btrfs_file_extent_item);
6989 extent_type = btrfs_file_extent_type(leaf, fi);
6990 if ((extent_type != BTRFS_FILE_EXTENT_REG &&
6991 extent_type != BTRFS_FILE_EXTENT_PREALLOC) ||
6992 (btrfs_file_extent_disk_bytenr(leaf, fi) !=
6993 extent_key->objectid)) {
6999 num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
7000 ext_offset = btrfs_file_extent_offset(leaf, fi);
7002 if (search_end == (u64)-1) {
7003 search_end = key.offset - ext_offset +
7004 btrfs_file_extent_ram_bytes(leaf, fi);
7007 if (!extent_locked) {
7008 lock_start = key.offset;
7009 lock_end = lock_start + num_bytes - 1;
7011 if (lock_start > key.offset ||
7012 lock_end + 1 < key.offset + num_bytes) {
7013 unlock_extent(&BTRFS_I(inode)->io_tree,
7014 lock_start, lock_end, GFP_NOFS);
7020 btrfs_release_path(root, path);
7022 inode = btrfs_iget_locked(root->fs_info->sb,
7023 key.objectid, root);
7024 if (inode->i_state & I_NEW) {
7025 BTRFS_I(inode)->root = root;
7026 BTRFS_I(inode)->location.objectid =
7028 BTRFS_I(inode)->location.type =
7029 BTRFS_INODE_ITEM_KEY;
7030 BTRFS_I(inode)->location.offset = 0;
7031 btrfs_read_locked_inode(inode);
7032 unlock_new_inode(inode);
7035 * some code call btrfs_commit_transaction while
7036 * holding the i_mutex, so we can't use mutex_lock
7039 if (is_bad_inode(inode) ||
7040 !mutex_trylock(&inode->i_mutex)) {
7043 key.offset = (u64)-1;
7048 if (!extent_locked) {
7049 struct btrfs_ordered_extent *ordered;
7051 btrfs_release_path(root, path);
7053 lock_extent(&BTRFS_I(inode)->io_tree, lock_start,
7054 lock_end, GFP_NOFS);
7055 ordered = btrfs_lookup_first_ordered_extent(inode,
7058 ordered->file_offset <= lock_end &&
7059 ordered->file_offset + ordered->len > lock_start) {
7060 unlock_extent(&BTRFS_I(inode)->io_tree,
7061 lock_start, lock_end, GFP_NOFS);
7062 btrfs_start_ordered_extent(inode, ordered, 1);
7063 btrfs_put_ordered_extent(ordered);
7064 key.offset += num_bytes;
7068 btrfs_put_ordered_extent(ordered);
7074 if (nr_extents == 1) {
7075 /* update extent pointer in place */
7076 btrfs_set_file_extent_disk_bytenr(leaf, fi,
7077 new_extents[0].disk_bytenr);
7078 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
7079 new_extents[0].disk_num_bytes);
7080 btrfs_mark_buffer_dirty(leaf);
7082 btrfs_drop_extent_cache(inode, key.offset,
7083 key.offset + num_bytes - 1, 0);
7085 ret = btrfs_inc_extent_ref(trans, root,
7086 new_extents[0].disk_bytenr,
7087 new_extents[0].disk_num_bytes,
7089 root->root_key.objectid,
7094 ret = btrfs_free_extent(trans, root,
7095 extent_key->objectid,
7098 btrfs_header_owner(leaf),
7099 btrfs_header_generation(leaf),
7103 btrfs_release_path(root, path);
7104 key.offset += num_bytes;
7112 * drop old extent pointer at first, then insert the
7113 * new pointers one bye one
7115 btrfs_release_path(root, path);
7116 ret = btrfs_drop_extents(trans, root, inode, key.offset,
7117 key.offset + num_bytes,
7118 key.offset, &alloc_hint);
7121 for (i = 0; i < nr_extents; i++) {
7122 if (ext_offset >= new_extents[i].num_bytes) {
7123 ext_offset -= new_extents[i].num_bytes;
7126 extent_len = min(new_extents[i].num_bytes -
7127 ext_offset, num_bytes);
7129 ret = btrfs_insert_empty_item(trans, root,
7134 leaf = path->nodes[0];
7135 fi = btrfs_item_ptr(leaf, path->slots[0],
7136 struct btrfs_file_extent_item);
7137 btrfs_set_file_extent_generation(leaf, fi,
7139 btrfs_set_file_extent_type(leaf, fi,
7140 BTRFS_FILE_EXTENT_REG);
7141 btrfs_set_file_extent_disk_bytenr(leaf, fi,
7142 new_extents[i].disk_bytenr);
7143 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
7144 new_extents[i].disk_num_bytes);
7145 btrfs_set_file_extent_ram_bytes(leaf, fi,
7146 new_extents[i].ram_bytes);
7148 btrfs_set_file_extent_compression(leaf, fi,
7149 new_extents[i].compression);
7150 btrfs_set_file_extent_encryption(leaf, fi,
7151 new_extents[i].encryption);
7152 btrfs_set_file_extent_other_encoding(leaf, fi,
7153 new_extents[i].other_encoding);
7155 btrfs_set_file_extent_num_bytes(leaf, fi,
7157 ext_offset += new_extents[i].offset;
7158 btrfs_set_file_extent_offset(leaf, fi,
7160 btrfs_mark_buffer_dirty(leaf);
7162 btrfs_drop_extent_cache(inode, key.offset,
7163 key.offset + extent_len - 1, 0);
7165 ret = btrfs_inc_extent_ref(trans, root,
7166 new_extents[i].disk_bytenr,
7167 new_extents[i].disk_num_bytes,
7169 root->root_key.objectid,
7170 trans->transid, key.objectid);
7172 btrfs_release_path(root, path);
7174 inode_add_bytes(inode, extent_len);
7177 num_bytes -= extent_len;
7178 key.offset += extent_len;
7183 BUG_ON(i >= nr_extents);
7187 if (extent_locked) {
7188 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
7189 lock_end, GFP_NOFS);
7193 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS &&
7194 key.offset >= search_end)
7201 btrfs_release_path(root, path);
7203 mutex_unlock(&inode->i_mutex);
7204 if (extent_locked) {
7205 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
7206 lock_end, GFP_NOFS);
7213 int btrfs_reloc_tree_cache_ref(struct btrfs_trans_handle *trans,
7214 struct btrfs_root *root,
7215 struct extent_buffer *buf, u64 orig_start)
7220 BUG_ON(btrfs_header_generation(buf) != trans->transid);
7221 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
7223 level = btrfs_header_level(buf);
7225 struct btrfs_leaf_ref *ref;
7226 struct btrfs_leaf_ref *orig_ref;
7228 orig_ref = btrfs_lookup_leaf_ref(root, orig_start);
7232 ref = btrfs_alloc_leaf_ref(root, orig_ref->nritems);
7234 btrfs_free_leaf_ref(root, orig_ref);
7238 ref->nritems = orig_ref->nritems;
7239 memcpy(ref->extents, orig_ref->extents,
7240 sizeof(ref->extents[0]) * ref->nritems);
7242 btrfs_free_leaf_ref(root, orig_ref);
7244 ref->root_gen = trans->transid;
7245 ref->bytenr = buf->start;
7246 ref->owner = btrfs_header_owner(buf);
7247 ref->generation = btrfs_header_generation(buf);
7249 ret = btrfs_add_leaf_ref(root, ref, 0);
7251 btrfs_free_leaf_ref(root, ref);
7256 static noinline int invalidate_extent_cache(struct btrfs_root *root,
7257 struct extent_buffer *leaf,
7258 struct btrfs_block_group_cache *group,
7259 struct btrfs_root *target_root)
7261 struct btrfs_key key;
7262 struct inode *inode = NULL;
7263 struct btrfs_file_extent_item *fi;
7264 struct extent_state *cached_state = NULL;
7266 u64 skip_objectid = 0;
7270 nritems = btrfs_header_nritems(leaf);
7271 for (i = 0; i < nritems; i++) {
7272 btrfs_item_key_to_cpu(leaf, &key, i);
7273 if (key.objectid == skip_objectid ||
7274 key.type != BTRFS_EXTENT_DATA_KEY)
7276 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
7277 if (btrfs_file_extent_type(leaf, fi) ==
7278 BTRFS_FILE_EXTENT_INLINE)
7280 if (btrfs_file_extent_disk_bytenr(leaf, fi) == 0)
7282 if (!inode || inode->i_ino != key.objectid) {
7284 inode = btrfs_ilookup(target_root->fs_info->sb,
7285 key.objectid, target_root, 1);
7288 skip_objectid = key.objectid;
7291 num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
7293 lock_extent_bits(&BTRFS_I(inode)->io_tree, key.offset,
7294 key.offset + num_bytes - 1, 0, &cached_state,
7296 btrfs_drop_extent_cache(inode, key.offset,
7297 key.offset + num_bytes - 1, 1);
7298 unlock_extent_cached(&BTRFS_I(inode)->io_tree, key.offset,
7299 key.offset + num_bytes - 1, &cached_state,
7307 static noinline int replace_extents_in_leaf(struct btrfs_trans_handle *trans,
7308 struct btrfs_root *root,
7309 struct extent_buffer *leaf,
7310 struct btrfs_block_group_cache *group,
7311 struct inode *reloc_inode)
7313 struct btrfs_key key;
7314 struct btrfs_key extent_key;
7315 struct btrfs_file_extent_item *fi;
7316 struct btrfs_leaf_ref *ref;
7317 struct disk_extent *new_extent;
7326 new_extent = kmalloc(sizeof(*new_extent), GFP_NOFS);
7327 BUG_ON(!new_extent);
7329 ref = btrfs_lookup_leaf_ref(root, leaf->start);
7333 nritems = btrfs_header_nritems(leaf);
7334 for (i = 0; i < nritems; i++) {
7335 btrfs_item_key_to_cpu(leaf, &key, i);
7336 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
7338 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
7339 if (btrfs_file_extent_type(leaf, fi) ==
7340 BTRFS_FILE_EXTENT_INLINE)
7342 bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
7343 num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
7348 if (bytenr >= group->key.objectid + group->key.offset ||
7349 bytenr + num_bytes <= group->key.objectid)
7352 extent_key.objectid = bytenr;
7353 extent_key.offset = num_bytes;
7354 extent_key.type = BTRFS_EXTENT_ITEM_KEY;
7356 ret = get_new_locations(reloc_inode, &extent_key,
7357 group->key.objectid, 1,
7358 &new_extent, &nr_extent);
7363 BUG_ON(ref->extents[ext_index].bytenr != bytenr);
7364 BUG_ON(ref->extents[ext_index].num_bytes != num_bytes);
7365 ref->extents[ext_index].bytenr = new_extent->disk_bytenr;
7366 ref->extents[ext_index].num_bytes = new_extent->disk_num_bytes;
7368 btrfs_set_file_extent_disk_bytenr(leaf, fi,
7369 new_extent->disk_bytenr);
7370 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
7371 new_extent->disk_num_bytes);
7372 btrfs_mark_buffer_dirty(leaf);
7374 ret = btrfs_inc_extent_ref(trans, root,
7375 new_extent->disk_bytenr,
7376 new_extent->disk_num_bytes,
7378 root->root_key.objectid,
7379 trans->transid, key.objectid);
7382 ret = btrfs_free_extent(trans, root,
7383 bytenr, num_bytes, leaf->start,
7384 btrfs_header_owner(leaf),
7385 btrfs_header_generation(leaf),
7391 BUG_ON(ext_index + 1 != ref->nritems);
7392 btrfs_free_leaf_ref(root, ref);
7396 int btrfs_free_reloc_root(struct btrfs_trans_handle *trans,
7397 struct btrfs_root *root)
7399 struct btrfs_root *reloc_root;
7402 if (root->reloc_root) {
7403 reloc_root = root->reloc_root;
7404 root->reloc_root = NULL;
7405 list_add(&reloc_root->dead_list,
7406 &root->fs_info->dead_reloc_roots);
7408 btrfs_set_root_bytenr(&reloc_root->root_item,
7409 reloc_root->node->start);
7410 btrfs_set_root_level(&root->root_item,
7411 btrfs_header_level(reloc_root->node));
7412 memset(&reloc_root->root_item.drop_progress, 0,
7413 sizeof(struct btrfs_disk_key));
7414 reloc_root->root_item.drop_level = 0;
7416 ret = btrfs_update_root(trans, root->fs_info->tree_root,
7417 &reloc_root->root_key,
7418 &reloc_root->root_item);
7424 int btrfs_drop_dead_reloc_roots(struct btrfs_root *root)
7426 struct btrfs_trans_handle *trans;
7427 struct btrfs_root *reloc_root;
7428 struct btrfs_root *prev_root = NULL;
7429 struct list_head dead_roots;
7433 INIT_LIST_HEAD(&dead_roots);
7434 list_splice_init(&root->fs_info->dead_reloc_roots, &dead_roots);
7436 while (!list_empty(&dead_roots)) {
7437 reloc_root = list_entry(dead_roots.prev,
7438 struct btrfs_root, dead_list);
7439 list_del_init(&reloc_root->dead_list);
7441 BUG_ON(reloc_root->commit_root != NULL);
7443 trans = btrfs_join_transaction(root, 1);
7446 mutex_lock(&root->fs_info->drop_mutex);
7447 ret = btrfs_drop_snapshot(trans, reloc_root);
7450 mutex_unlock(&root->fs_info->drop_mutex);
7452 nr = trans->blocks_used;
7453 ret = btrfs_end_transaction(trans, root);
7455 btrfs_btree_balance_dirty(root, nr);
7458 free_extent_buffer(reloc_root->node);
7460 ret = btrfs_del_root(trans, root->fs_info->tree_root,
7461 &reloc_root->root_key);
7463 mutex_unlock(&root->fs_info->drop_mutex);
7465 nr = trans->blocks_used;
7466 ret = btrfs_end_transaction(trans, root);
7468 btrfs_btree_balance_dirty(root, nr);
7471 prev_root = reloc_root;
7474 btrfs_remove_leaf_refs(prev_root, (u64)-1, 0);
7480 int btrfs_add_dead_reloc_root(struct btrfs_root *root)
7482 list_add(&root->dead_list, &root->fs_info->dead_reloc_roots);
7486 int btrfs_cleanup_reloc_trees(struct btrfs_root *root)
7488 struct btrfs_root *reloc_root;
7489 struct btrfs_trans_handle *trans;
7490 struct btrfs_key location;
7494 mutex_lock(&root->fs_info->tree_reloc_mutex);
7495 ret = btrfs_find_dead_roots(root, BTRFS_TREE_RELOC_OBJECTID, NULL);
7497 found = !list_empty(&root->fs_info->dead_reloc_roots);
7498 mutex_unlock(&root->fs_info->tree_reloc_mutex);
7501 trans = btrfs_start_transaction(root, 1);
7503 ret = btrfs_commit_transaction(trans, root);
7507 location.objectid = BTRFS_DATA_RELOC_TREE_OBJECTID;
7508 location.offset = (u64)-1;
7509 location.type = BTRFS_ROOT_ITEM_KEY;
7511 reloc_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
7512 BUG_ON(!reloc_root);
7513 btrfs_orphan_cleanup(reloc_root);
7517 static noinline int init_reloc_tree(struct btrfs_trans_handle *trans,
7518 struct btrfs_root *root)
7520 struct btrfs_root *reloc_root;
7521 struct extent_buffer *eb;
7522 struct btrfs_root_item *root_item;
7523 struct btrfs_key root_key;
7526 BUG_ON(!root->ref_cows);
7527 if (root->reloc_root)
7530 root_item = kmalloc(sizeof(*root_item), GFP_NOFS);
7533 ret = btrfs_copy_root(trans, root, root->commit_root,
7534 &eb, BTRFS_TREE_RELOC_OBJECTID);
7537 root_key.objectid = BTRFS_TREE_RELOC_OBJECTID;
7538 root_key.offset = root->root_key.objectid;
7539 root_key.type = BTRFS_ROOT_ITEM_KEY;
7541 memcpy(root_item, &root->root_item, sizeof(root_item));
7542 btrfs_set_root_refs(root_item, 0);
7543 btrfs_set_root_bytenr(root_item, eb->start);
7544 btrfs_set_root_level(root_item, btrfs_header_level(eb));
7545 btrfs_set_root_generation(root_item, trans->transid);
7547 btrfs_tree_unlock(eb);
7548 free_extent_buffer(eb);
7550 ret = btrfs_insert_root(trans, root->fs_info->tree_root,
7551 &root_key, root_item);
7555 reloc_root = btrfs_read_fs_root_no_radix(root->fs_info->tree_root,
7557 BUG_ON(!reloc_root);
7558 reloc_root->last_trans = trans->transid;
7559 reloc_root->commit_root = NULL;
7560 reloc_root->ref_tree = &root->fs_info->reloc_ref_tree;
7562 root->reloc_root = reloc_root;
7567 * Core function of space balance.
7569 * The idea is using reloc trees to relocate tree blocks in reference
7570 * counted roots. There is one reloc tree for each subvol, and all
7571 * reloc trees share same root key objectid. Reloc trees are snapshots
7572 * of the latest committed roots of subvols (root->commit_root).
7574 * To relocate a tree block referenced by a subvol, there are two steps.
7575 * COW the block through subvol's reloc tree, then update block pointer
7576 * in the subvol to point to the new block. Since all reloc trees share
7577 * same root key objectid, doing special handing for tree blocks owned
7578 * by them is easy. Once a tree block has been COWed in one reloc tree,
7579 * we can use the resulting new block directly when the same block is
7580 * required to COW again through other reloc trees. By this way, relocated
7581 * tree blocks are shared between reloc trees, so they are also shared
7584 static noinline int relocate_one_path(struct btrfs_trans_handle *trans,
7585 struct btrfs_root *root,
7586 struct btrfs_path *path,
7587 struct btrfs_key *first_key,
7588 struct btrfs_ref_path *ref_path,
7589 struct btrfs_block_group_cache *group,
7590 struct inode *reloc_inode)
7592 struct btrfs_root *reloc_root;
7593 struct extent_buffer *eb = NULL;
7594 struct btrfs_key *keys;
7598 int lowest_level = 0;
7601 if (ref_path->owner_objectid < BTRFS_FIRST_FREE_OBJECTID)
7602 lowest_level = ref_path->owner_objectid;
7604 if (!root->ref_cows) {
7605 path->lowest_level = lowest_level;
7606 ret = btrfs_search_slot(trans, root, first_key, path, 0, 1);
7608 path->lowest_level = 0;
7609 btrfs_release_path(root, path);
7613 mutex_lock(&root->fs_info->tree_reloc_mutex);
7614 ret = init_reloc_tree(trans, root);
7616 reloc_root = root->reloc_root;
7618 shared_level = ref_path->shared_level;
7619 ref_path->shared_level = BTRFS_MAX_LEVEL - 1;
7621 keys = ref_path->node_keys;
7622 nodes = ref_path->new_nodes;
7623 memset(&keys[shared_level + 1], 0,
7624 sizeof(*keys) * (BTRFS_MAX_LEVEL - shared_level - 1));
7625 memset(&nodes[shared_level + 1], 0,
7626 sizeof(*nodes) * (BTRFS_MAX_LEVEL - shared_level - 1));
7628 if (nodes[lowest_level] == 0) {
7629 path->lowest_level = lowest_level;
7630 ret = btrfs_search_slot(trans, reloc_root, first_key, path,
7633 for (level = lowest_level; level < BTRFS_MAX_LEVEL; level++) {
7634 eb = path->nodes[level];
7635 if (!eb || eb == reloc_root->node)
7637 nodes[level] = eb->start;
7639 btrfs_item_key_to_cpu(eb, &keys[level], 0);
7641 btrfs_node_key_to_cpu(eb, &keys[level], 0);
7644 ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7645 eb = path->nodes[0];
7646 ret = replace_extents_in_leaf(trans, reloc_root, eb,
7647 group, reloc_inode);
7650 btrfs_release_path(reloc_root, path);
7652 ret = btrfs_merge_path(trans, reloc_root, keys, nodes,
7658 * replace tree blocks in the fs tree with tree blocks in
7661 ret = btrfs_merge_path(trans, root, keys, nodes, lowest_level);
7664 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7665 ret = btrfs_search_slot(trans, reloc_root, first_key, path,
7668 extent_buffer_get(path->nodes[0]);
7669 eb = path->nodes[0];
7670 btrfs_release_path(reloc_root, path);
7671 ret = invalidate_extent_cache(reloc_root, eb, group, root);
7673 free_extent_buffer(eb);
7676 mutex_unlock(&root->fs_info->tree_reloc_mutex);
7677 path->lowest_level = 0;
7681 static noinline int relocate_tree_block(struct btrfs_trans_handle *trans,
7682 struct btrfs_root *root,
7683 struct btrfs_path *path,
7684 struct btrfs_key *first_key,
7685 struct btrfs_ref_path *ref_path)
7689 ret = relocate_one_path(trans, root, path, first_key,
7690 ref_path, NULL, NULL);
7696 static noinline int del_extent_zero(struct btrfs_trans_handle *trans,
7697 struct btrfs_root *extent_root,
7698 struct btrfs_path *path,
7699 struct btrfs_key *extent_key)
7703 ret = btrfs_search_slot(trans, extent_root, extent_key, path, -1, 1);
7706 ret = btrfs_del_item(trans, extent_root, path);
7708 btrfs_release_path(extent_root, path);
7712 static noinline struct btrfs_root *read_ref_root(struct btrfs_fs_info *fs_info,
7713 struct btrfs_ref_path *ref_path)
7715 struct btrfs_key root_key;
7717 root_key.objectid = ref_path->root_objectid;
7718 root_key.type = BTRFS_ROOT_ITEM_KEY;
7719 if (is_cowonly_root(ref_path->root_objectid))
7720 root_key.offset = 0;
7722 root_key.offset = (u64)-1;
7724 return btrfs_read_fs_root_no_name(fs_info, &root_key);
7727 static noinline int relocate_one_extent(struct btrfs_root *extent_root,
7728 struct btrfs_path *path,
7729 struct btrfs_key *extent_key,
7730 struct btrfs_block_group_cache *group,
7731 struct inode *reloc_inode, int pass)
7733 struct btrfs_trans_handle *trans;
7734 struct btrfs_root *found_root;
7735 struct btrfs_ref_path *ref_path = NULL;
7736 struct disk_extent *new_extents = NULL;
7741 struct btrfs_key first_key;
7745 trans = btrfs_start_transaction(extent_root, 1);
7748 if (extent_key->objectid == 0) {
7749 ret = del_extent_zero(trans, extent_root, path, extent_key);
7753 ref_path = kmalloc(sizeof(*ref_path), GFP_NOFS);
7759 for (loops = 0; ; loops++) {
7761 ret = btrfs_first_ref_path(trans, extent_root, ref_path,
7762 extent_key->objectid);
7764 ret = btrfs_next_ref_path(trans, extent_root, ref_path);
7771 if (ref_path->root_objectid == BTRFS_TREE_LOG_OBJECTID ||
7772 ref_path->root_objectid == BTRFS_TREE_RELOC_OBJECTID)
7775 found_root = read_ref_root(extent_root->fs_info, ref_path);
7776 BUG_ON(!found_root);
7778 * for reference counted tree, only process reference paths
7779 * rooted at the latest committed root.
7781 if (found_root->ref_cows &&
7782 ref_path->root_generation != found_root->root_key.offset)
7785 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7788 * copy data extents to new locations
7790 u64 group_start = group->key.objectid;
7791 ret = relocate_data_extent(reloc_inode,
7800 level = ref_path->owner_objectid;
7803 if (prev_block != ref_path->nodes[level]) {
7804 struct extent_buffer *eb;
7805 u64 block_start = ref_path->nodes[level];
7806 u64 block_size = btrfs_level_size(found_root, level);
7808 eb = read_tree_block(found_root, block_start,
7810 btrfs_tree_lock(eb);
7811 BUG_ON(level != btrfs_header_level(eb));
7814 btrfs_item_key_to_cpu(eb, &first_key, 0);
7816 btrfs_node_key_to_cpu(eb, &first_key, 0);
7818 btrfs_tree_unlock(eb);
7819 free_extent_buffer(eb);
7820 prev_block = block_start;
7823 mutex_lock(&extent_root->fs_info->trans_mutex);
7824 btrfs_record_root_in_trans(found_root);
7825 mutex_unlock(&extent_root->fs_info->trans_mutex);
7826 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7828 * try to update data extent references while
7829 * keeping metadata shared between snapshots.
7832 ret = relocate_one_path(trans, found_root,
7833 path, &first_key, ref_path,
7834 group, reloc_inode);
7840 * use fallback method to process the remaining
7844 u64 group_start = group->key.objectid;
7845 new_extents = kmalloc(sizeof(*new_extents),
7848 ret = get_new_locations(reloc_inode,
7856 ret = replace_one_extent(trans, found_root,
7858 &first_key, ref_path,
7859 new_extents, nr_extents);
7861 ret = relocate_tree_block(trans, found_root, path,
7862 &first_key, ref_path);
7869 btrfs_end_transaction(trans, extent_root);
7876 static u64 update_block_group_flags(struct btrfs_root *root, u64 flags)
7879 u64 stripped = BTRFS_BLOCK_GROUP_RAID0 |
7880 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
7882 num_devices = root->fs_info->fs_devices->rw_devices;
7883 if (num_devices == 1) {
7884 stripped |= BTRFS_BLOCK_GROUP_DUP;
7885 stripped = flags & ~stripped;
7887 /* turn raid0 into single device chunks */
7888 if (flags & BTRFS_BLOCK_GROUP_RAID0)
7891 /* turn mirroring into duplication */
7892 if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
7893 BTRFS_BLOCK_GROUP_RAID10))
7894 return stripped | BTRFS_BLOCK_GROUP_DUP;
7897 /* they already had raid on here, just return */
7898 if (flags & stripped)
7901 stripped |= BTRFS_BLOCK_GROUP_DUP;
7902 stripped = flags & ~stripped;
7904 /* switch duplicated blocks with raid1 */
7905 if (flags & BTRFS_BLOCK_GROUP_DUP)
7906 return stripped | BTRFS_BLOCK_GROUP_RAID1;
7908 /* turn single device chunks into raid0 */
7909 return stripped | BTRFS_BLOCK_GROUP_RAID0;
7914 static int set_block_group_ro(struct btrfs_block_group_cache *cache)
7916 struct btrfs_space_info *sinfo = cache->space_info;
7923 spin_lock(&sinfo->lock);
7924 spin_lock(&cache->lock);
7925 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
7926 cache->bytes_super - btrfs_block_group_used(&cache->item);
7928 if (sinfo->bytes_used + sinfo->bytes_reserved + sinfo->bytes_pinned +
7929 sinfo->bytes_may_use + sinfo->bytes_readonly +
7930 cache->reserved_pinned + num_bytes < sinfo->total_bytes) {
7931 sinfo->bytes_readonly += num_bytes;
7932 sinfo->bytes_reserved += cache->reserved_pinned;
7933 cache->reserved_pinned = 0;
7937 spin_unlock(&cache->lock);
7938 spin_unlock(&sinfo->lock);
7942 int btrfs_set_block_group_ro(struct btrfs_root *root,
7943 struct btrfs_block_group_cache *cache)
7946 struct btrfs_trans_handle *trans;
7952 trans = btrfs_join_transaction(root, 1);
7953 BUG_ON(IS_ERR(trans));
7955 alloc_flags = update_block_group_flags(root, cache->flags);
7956 if (alloc_flags != cache->flags)
7957 do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags, 1);
7959 ret = set_block_group_ro(cache);
7962 alloc_flags = get_alloc_profile(root, cache->space_info->flags);
7963 ret = do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags, 1);
7966 ret = set_block_group_ro(cache);
7968 btrfs_end_transaction(trans, root);
7972 int btrfs_set_block_group_rw(struct btrfs_root *root,
7973 struct btrfs_block_group_cache *cache)
7975 struct btrfs_space_info *sinfo = cache->space_info;
7980 spin_lock(&sinfo->lock);
7981 spin_lock(&cache->lock);
7982 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
7983 cache->bytes_super - btrfs_block_group_used(&cache->item);
7984 sinfo->bytes_readonly -= num_bytes;
7986 spin_unlock(&cache->lock);
7987 spin_unlock(&sinfo->lock);
7992 * checks to see if its even possible to relocate this block group.
7994 * @return - -1 if it's not a good idea to relocate this block group, 0 if its
7995 * ok to go ahead and try.
7997 int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
7999 struct btrfs_block_group_cache *block_group;
8000 struct btrfs_space_info *space_info;
8001 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
8002 struct btrfs_device *device;
8006 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
8008 /* odd, couldn't find the block group, leave it alone */
8012 /* no bytes used, we're good */
8013 if (!btrfs_block_group_used(&block_group->item))
8016 space_info = block_group->space_info;
8017 spin_lock(&space_info->lock);
8019 full = space_info->full;
8022 * if this is the last block group we have in this space, we can't
8023 * relocate it unless we're able to allocate a new chunk below.
8025 * Otherwise, we need to make sure we have room in the space to handle
8026 * all of the extents from this block group. If we can, we're good
8028 if ((space_info->total_bytes != block_group->key.offset) &&
8029 (space_info->bytes_used + space_info->bytes_reserved +
8030 space_info->bytes_pinned + space_info->bytes_readonly +
8031 btrfs_block_group_used(&block_group->item) <
8032 space_info->total_bytes)) {
8033 spin_unlock(&space_info->lock);
8036 spin_unlock(&space_info->lock);
8039 * ok we don't have enough space, but maybe we have free space on our
8040 * devices to allocate new chunks for relocation, so loop through our
8041 * alloc devices and guess if we have enough space. However, if we
8042 * were marked as full, then we know there aren't enough chunks, and we
8049 mutex_lock(&root->fs_info->chunk_mutex);
8050 list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
8051 u64 min_free = btrfs_block_group_used(&block_group->item);
8052 u64 dev_offset, max_avail;
8055 * check to make sure we can actually find a chunk with enough
8056 * space to fit our block group in.
8058 if (device->total_bytes > device->bytes_used + min_free) {
8059 ret = find_free_dev_extent(NULL, device, min_free,
8060 &dev_offset, &max_avail);
8066 mutex_unlock(&root->fs_info->chunk_mutex);
8068 btrfs_put_block_group(block_group);
8072 static int find_first_block_group(struct btrfs_root *root,
8073 struct btrfs_path *path, struct btrfs_key *key)
8076 struct btrfs_key found_key;
8077 struct extent_buffer *leaf;
8080 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
8085 slot = path->slots[0];
8086 leaf = path->nodes[0];
8087 if (slot >= btrfs_header_nritems(leaf)) {
8088 ret = btrfs_next_leaf(root, path);
8095 btrfs_item_key_to_cpu(leaf, &found_key, slot);
8097 if (found_key.objectid >= key->objectid &&
8098 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
8108 void btrfs_put_block_group_cache(struct btrfs_fs_info *info)
8110 struct btrfs_block_group_cache *block_group;
8114 struct inode *inode;
8116 block_group = btrfs_lookup_first_block_group(info, last);
8117 while (block_group) {
8118 spin_lock(&block_group->lock);
8119 if (block_group->iref)
8121 spin_unlock(&block_group->lock);
8122 block_group = next_block_group(info->tree_root,
8132 inode = block_group->inode;
8133 block_group->iref = 0;
8134 block_group->inode = NULL;
8135 spin_unlock(&block_group->lock);
8137 last = block_group->key.objectid + block_group->key.offset;
8138 btrfs_put_block_group(block_group);
8142 int btrfs_free_block_groups(struct btrfs_fs_info *info)
8144 struct btrfs_block_group_cache *block_group;
8145 struct btrfs_space_info *space_info;
8146 struct btrfs_caching_control *caching_ctl;
8149 down_write(&info->extent_commit_sem);
8150 while (!list_empty(&info->caching_block_groups)) {
8151 caching_ctl = list_entry(info->caching_block_groups.next,
8152 struct btrfs_caching_control, list);
8153 list_del(&caching_ctl->list);
8154 put_caching_control(caching_ctl);
8156 up_write(&info->extent_commit_sem);
8158 spin_lock(&info->block_group_cache_lock);
8159 while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
8160 block_group = rb_entry(n, struct btrfs_block_group_cache,
8162 rb_erase(&block_group->cache_node,
8163 &info->block_group_cache_tree);
8164 spin_unlock(&info->block_group_cache_lock);
8166 down_write(&block_group->space_info->groups_sem);
8167 list_del(&block_group->list);
8168 up_write(&block_group->space_info->groups_sem);
8170 if (block_group->cached == BTRFS_CACHE_STARTED)
8171 wait_block_group_cache_done(block_group);
8173 btrfs_remove_free_space_cache(block_group);
8174 btrfs_put_block_group(block_group);
8176 spin_lock(&info->block_group_cache_lock);
8178 spin_unlock(&info->block_group_cache_lock);
8180 /* now that all the block groups are freed, go through and
8181 * free all the space_info structs. This is only called during
8182 * the final stages of unmount, and so we know nobody is
8183 * using them. We call synchronize_rcu() once before we start,
8184 * just to be on the safe side.
8188 release_global_block_rsv(info);
8190 while(!list_empty(&info->space_info)) {
8191 space_info = list_entry(info->space_info.next,
8192 struct btrfs_space_info,
8194 if (space_info->bytes_pinned > 0 ||
8195 space_info->bytes_reserved > 0) {
8197 dump_space_info(space_info, 0, 0);
8199 list_del(&space_info->list);
8205 static void __link_block_group(struct btrfs_space_info *space_info,
8206 struct btrfs_block_group_cache *cache)
8208 int index = get_block_group_index(cache);
8210 down_write(&space_info->groups_sem);
8211 list_add_tail(&cache->list, &space_info->block_groups[index]);
8212 up_write(&space_info->groups_sem);
8215 int btrfs_read_block_groups(struct btrfs_root *root)
8217 struct btrfs_path *path;
8219 struct btrfs_block_group_cache *cache;
8220 struct btrfs_fs_info *info = root->fs_info;
8221 struct btrfs_space_info *space_info;
8222 struct btrfs_key key;
8223 struct btrfs_key found_key;
8224 struct extent_buffer *leaf;
8228 root = info->extent_root;
8231 btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
8232 path = btrfs_alloc_path();
8236 cache_gen = btrfs_super_cache_generation(&root->fs_info->super_copy);
8237 if (cache_gen != 0 &&
8238 btrfs_super_generation(&root->fs_info->super_copy) != cache_gen)
8240 if (btrfs_test_opt(root, CLEAR_CACHE))
8242 if (!btrfs_test_opt(root, SPACE_CACHE) && cache_gen)
8243 printk(KERN_INFO "btrfs: disk space caching is enabled\n");
8246 ret = find_first_block_group(root, path, &key);
8252 leaf = path->nodes[0];
8253 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
8254 cache = kzalloc(sizeof(*cache), GFP_NOFS);
8260 atomic_set(&cache->count, 1);
8261 spin_lock_init(&cache->lock);
8262 spin_lock_init(&cache->tree_lock);
8263 cache->fs_info = info;
8264 INIT_LIST_HEAD(&cache->list);
8265 INIT_LIST_HEAD(&cache->cluster_list);
8268 cache->disk_cache_state = BTRFS_DC_CLEAR;
8271 * we only want to have 32k of ram per block group for keeping
8272 * track of free space, and if we pass 1/2 of that we want to
8273 * start converting things over to using bitmaps
8275 cache->extents_thresh = ((1024 * 32) / 2) /
8276 sizeof(struct btrfs_free_space);
8278 read_extent_buffer(leaf, &cache->item,
8279 btrfs_item_ptr_offset(leaf, path->slots[0]),
8280 sizeof(cache->item));
8281 memcpy(&cache->key, &found_key, sizeof(found_key));
8283 key.objectid = found_key.objectid + found_key.offset;
8284 btrfs_release_path(root, path);
8285 cache->flags = btrfs_block_group_flags(&cache->item);
8286 cache->sectorsize = root->sectorsize;
8289 * check for two cases, either we are full, and therefore
8290 * don't need to bother with the caching work since we won't
8291 * find any space, or we are empty, and we can just add all
8292 * the space in and be done with it. This saves us _alot_ of
8293 * time, particularly in the full case.
8295 if (found_key.offset == btrfs_block_group_used(&cache->item)) {
8296 exclude_super_stripes(root, cache);
8297 cache->last_byte_to_unpin = (u64)-1;
8298 cache->cached = BTRFS_CACHE_FINISHED;
8299 free_excluded_extents(root, cache);
8300 } else if (btrfs_block_group_used(&cache->item) == 0) {
8301 exclude_super_stripes(root, cache);
8302 cache->last_byte_to_unpin = (u64)-1;
8303 cache->cached = BTRFS_CACHE_FINISHED;
8304 add_new_free_space(cache, root->fs_info,
8306 found_key.objectid +
8308 free_excluded_extents(root, cache);
8311 ret = update_space_info(info, cache->flags, found_key.offset,
8312 btrfs_block_group_used(&cache->item),
8315 cache->space_info = space_info;
8316 spin_lock(&cache->space_info->lock);
8317 cache->space_info->bytes_readonly += cache->bytes_super;
8318 spin_unlock(&cache->space_info->lock);
8320 __link_block_group(space_info, cache);
8322 ret = btrfs_add_block_group_cache(root->fs_info, cache);
8325 set_avail_alloc_bits(root->fs_info, cache->flags);
8326 if (btrfs_chunk_readonly(root, cache->key.objectid))
8327 set_block_group_ro(cache);
8330 list_for_each_entry_rcu(space_info, &root->fs_info->space_info, list) {
8331 if (!(get_alloc_profile(root, space_info->flags) &
8332 (BTRFS_BLOCK_GROUP_RAID10 |
8333 BTRFS_BLOCK_GROUP_RAID1 |
8334 BTRFS_BLOCK_GROUP_DUP)))
8337 * avoid allocating from un-mirrored block group if there are
8338 * mirrored block groups.
8340 list_for_each_entry(cache, &space_info->block_groups[3], list)
8341 set_block_group_ro(cache);
8342 list_for_each_entry(cache, &space_info->block_groups[4], list)
8343 set_block_group_ro(cache);
8346 init_global_block_rsv(info);
8349 btrfs_free_path(path);
8353 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
8354 struct btrfs_root *root, u64 bytes_used,
8355 u64 type, u64 chunk_objectid, u64 chunk_offset,
8359 struct btrfs_root *extent_root;
8360 struct btrfs_block_group_cache *cache;
8362 extent_root = root->fs_info->extent_root;
8364 root->fs_info->last_trans_log_full_commit = trans->transid;
8366 cache = kzalloc(sizeof(*cache), GFP_NOFS);
8370 cache->key.objectid = chunk_offset;
8371 cache->key.offset = size;
8372 cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
8373 cache->sectorsize = root->sectorsize;
8374 cache->fs_info = root->fs_info;
8377 * we only want to have 32k of ram per block group for keeping track
8378 * of free space, and if we pass 1/2 of that we want to start
8379 * converting things over to using bitmaps
8381 cache->extents_thresh = ((1024 * 32) / 2) /
8382 sizeof(struct btrfs_free_space);
8383 atomic_set(&cache->count, 1);
8384 spin_lock_init(&cache->lock);
8385 spin_lock_init(&cache->tree_lock);
8386 INIT_LIST_HEAD(&cache->list);
8387 INIT_LIST_HEAD(&cache->cluster_list);
8389 btrfs_set_block_group_used(&cache->item, bytes_used);
8390 btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
8391 cache->flags = type;
8392 btrfs_set_block_group_flags(&cache->item, type);
8394 cache->last_byte_to_unpin = (u64)-1;
8395 cache->cached = BTRFS_CACHE_FINISHED;
8396 exclude_super_stripes(root, cache);
8398 add_new_free_space(cache, root->fs_info, chunk_offset,
8399 chunk_offset + size);
8401 free_excluded_extents(root, cache);
8403 ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
8404 &cache->space_info);
8407 spin_lock(&cache->space_info->lock);
8408 cache->space_info->bytes_readonly += cache->bytes_super;
8409 spin_unlock(&cache->space_info->lock);
8411 __link_block_group(cache->space_info, cache);
8413 ret = btrfs_add_block_group_cache(root->fs_info, cache);
8416 ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
8417 sizeof(cache->item));
8420 set_avail_alloc_bits(extent_root->fs_info, type);
8425 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
8426 struct btrfs_root *root, u64 group_start)
8428 struct btrfs_path *path;
8429 struct btrfs_block_group_cache *block_group;
8430 struct btrfs_free_cluster *cluster;
8431 struct btrfs_root *tree_root = root->fs_info->tree_root;
8432 struct btrfs_key key;
8433 struct inode *inode;
8437 root = root->fs_info->extent_root;
8439 block_group = btrfs_lookup_block_group(root->fs_info, group_start);
8440 BUG_ON(!block_group);
8441 BUG_ON(!block_group->ro);
8443 memcpy(&key, &block_group->key, sizeof(key));
8444 if (block_group->flags & (BTRFS_BLOCK_GROUP_DUP |
8445 BTRFS_BLOCK_GROUP_RAID1 |
8446 BTRFS_BLOCK_GROUP_RAID10))
8451 /* make sure this block group isn't part of an allocation cluster */
8452 cluster = &root->fs_info->data_alloc_cluster;
8453 spin_lock(&cluster->refill_lock);
8454 btrfs_return_cluster_to_free_space(block_group, cluster);
8455 spin_unlock(&cluster->refill_lock);
8458 * make sure this block group isn't part of a metadata
8459 * allocation cluster
8461 cluster = &root->fs_info->meta_alloc_cluster;
8462 spin_lock(&cluster->refill_lock);
8463 btrfs_return_cluster_to_free_space(block_group, cluster);
8464 spin_unlock(&cluster->refill_lock);
8466 path = btrfs_alloc_path();
8469 inode = lookup_free_space_inode(root, block_group, path);
8470 if (!IS_ERR(inode)) {
8471 btrfs_orphan_add(trans, inode);
8473 /* One for the block groups ref */
8474 spin_lock(&block_group->lock);
8475 if (block_group->iref) {
8476 block_group->iref = 0;
8477 block_group->inode = NULL;
8478 spin_unlock(&block_group->lock);
8481 spin_unlock(&block_group->lock);
8483 /* One for our lookup ref */
8487 key.objectid = BTRFS_FREE_SPACE_OBJECTID;
8488 key.offset = block_group->key.objectid;
8491 ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1);
8495 btrfs_release_path(tree_root, path);
8497 ret = btrfs_del_item(trans, tree_root, path);
8500 btrfs_release_path(tree_root, path);
8503 spin_lock(&root->fs_info->block_group_cache_lock);
8504 rb_erase(&block_group->cache_node,
8505 &root->fs_info->block_group_cache_tree);
8506 spin_unlock(&root->fs_info->block_group_cache_lock);
8508 down_write(&block_group->space_info->groups_sem);
8510 * we must use list_del_init so people can check to see if they
8511 * are still on the list after taking the semaphore
8513 list_del_init(&block_group->list);
8514 up_write(&block_group->space_info->groups_sem);
8516 if (block_group->cached == BTRFS_CACHE_STARTED)
8517 wait_block_group_cache_done(block_group);
8519 btrfs_remove_free_space_cache(block_group);
8521 spin_lock(&block_group->space_info->lock);
8522 block_group->space_info->total_bytes -= block_group->key.offset;
8523 block_group->space_info->bytes_readonly -= block_group->key.offset;
8524 block_group->space_info->disk_total -= block_group->key.offset * factor;
8525 spin_unlock(&block_group->space_info->lock);
8527 memcpy(&key, &block_group->key, sizeof(key));
8529 btrfs_clear_space_info_full(root->fs_info);
8531 btrfs_put_block_group(block_group);
8532 btrfs_put_block_group(block_group);
8534 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
8540 ret = btrfs_del_item(trans, root, path);
8542 btrfs_free_path(path);