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,
432 struct btrfs_root *root,
435 struct btrfs_fs_info *fs_info = cache->fs_info;
436 struct btrfs_caching_control *caching_ctl;
437 struct task_struct *tsk;
441 if (cache->cached != BTRFS_CACHE_NO)
445 * We can't do the read from on-disk cache during a commit since we need
446 * to have the normal tree locking. Also if we are currently trying to
447 * allocate blocks for the tree root we can't do the fast caching since
448 * we likely hold important locks.
450 if (!trans->transaction->in_commit &&
451 (root && root != root->fs_info->tree_root)) {
452 spin_lock(&cache->lock);
453 if (cache->cached != BTRFS_CACHE_NO) {
454 spin_unlock(&cache->lock);
457 cache->cached = BTRFS_CACHE_STARTED;
458 spin_unlock(&cache->lock);
460 ret = load_free_space_cache(fs_info, cache);
462 spin_lock(&cache->lock);
464 cache->cached = BTRFS_CACHE_FINISHED;
465 cache->last_byte_to_unpin = (u64)-1;
467 cache->cached = BTRFS_CACHE_NO;
469 spin_unlock(&cache->lock);
477 caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_KERNEL);
478 BUG_ON(!caching_ctl);
480 INIT_LIST_HEAD(&caching_ctl->list);
481 mutex_init(&caching_ctl->mutex);
482 init_waitqueue_head(&caching_ctl->wait);
483 caching_ctl->block_group = cache;
484 caching_ctl->progress = cache->key.objectid;
485 /* one for caching kthread, one for caching block group list */
486 atomic_set(&caching_ctl->count, 2);
488 spin_lock(&cache->lock);
489 if (cache->cached != BTRFS_CACHE_NO) {
490 spin_unlock(&cache->lock);
494 cache->caching_ctl = caching_ctl;
495 cache->cached = BTRFS_CACHE_STARTED;
496 spin_unlock(&cache->lock);
498 down_write(&fs_info->extent_commit_sem);
499 list_add_tail(&caching_ctl->list, &fs_info->caching_block_groups);
500 up_write(&fs_info->extent_commit_sem);
502 atomic_inc(&cache->space_info->caching_threads);
503 btrfs_get_block_group(cache);
505 tsk = kthread_run(caching_kthread, cache, "btrfs-cache-%llu\n",
506 cache->key.objectid);
509 printk(KERN_ERR "error running thread %d\n", ret);
517 * return the block group that starts at or after bytenr
519 static struct btrfs_block_group_cache *
520 btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr)
522 struct btrfs_block_group_cache *cache;
524 cache = block_group_cache_tree_search(info, bytenr, 0);
530 * return the block group that contains the given bytenr
532 struct btrfs_block_group_cache *btrfs_lookup_block_group(
533 struct btrfs_fs_info *info,
536 struct btrfs_block_group_cache *cache;
538 cache = block_group_cache_tree_search(info, bytenr, 1);
543 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
546 struct list_head *head = &info->space_info;
547 struct btrfs_space_info *found;
549 flags &= BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_SYSTEM |
550 BTRFS_BLOCK_GROUP_METADATA;
553 list_for_each_entry_rcu(found, head, list) {
554 if (found->flags & flags) {
564 * after adding space to the filesystem, we need to clear the full flags
565 * on all the space infos.
567 void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
569 struct list_head *head = &info->space_info;
570 struct btrfs_space_info *found;
573 list_for_each_entry_rcu(found, head, list)
578 static u64 div_factor(u64 num, int factor)
587 static u64 div_factor_fine(u64 num, int factor)
596 u64 btrfs_find_block_group(struct btrfs_root *root,
597 u64 search_start, u64 search_hint, int owner)
599 struct btrfs_block_group_cache *cache;
601 u64 last = max(search_hint, search_start);
608 cache = btrfs_lookup_first_block_group(root->fs_info, last);
612 spin_lock(&cache->lock);
613 last = cache->key.objectid + cache->key.offset;
614 used = btrfs_block_group_used(&cache->item);
616 if ((full_search || !cache->ro) &&
617 block_group_bits(cache, BTRFS_BLOCK_GROUP_METADATA)) {
618 if (used + cache->pinned + cache->reserved <
619 div_factor(cache->key.offset, factor)) {
620 group_start = cache->key.objectid;
621 spin_unlock(&cache->lock);
622 btrfs_put_block_group(cache);
626 spin_unlock(&cache->lock);
627 btrfs_put_block_group(cache);
635 if (!full_search && factor < 10) {
645 /* simple helper to search for an existing extent at a given offset */
646 int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len)
649 struct btrfs_key key;
650 struct btrfs_path *path;
652 path = btrfs_alloc_path();
654 key.objectid = start;
656 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
657 ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path,
659 btrfs_free_path(path);
664 * helper function to lookup reference count and flags of extent.
666 * the head node for delayed ref is used to store the sum of all the
667 * reference count modifications queued up in the rbtree. the head
668 * node may also store the extent flags to set. This way you can check
669 * to see what the reference count and extent flags would be if all of
670 * the delayed refs are not processed.
672 int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
673 struct btrfs_root *root, u64 bytenr,
674 u64 num_bytes, u64 *refs, u64 *flags)
676 struct btrfs_delayed_ref_head *head;
677 struct btrfs_delayed_ref_root *delayed_refs;
678 struct btrfs_path *path;
679 struct btrfs_extent_item *ei;
680 struct extent_buffer *leaf;
681 struct btrfs_key key;
687 path = btrfs_alloc_path();
691 key.objectid = bytenr;
692 key.type = BTRFS_EXTENT_ITEM_KEY;
693 key.offset = num_bytes;
695 path->skip_locking = 1;
696 path->search_commit_root = 1;
699 ret = btrfs_search_slot(trans, root->fs_info->extent_root,
705 leaf = path->nodes[0];
706 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
707 if (item_size >= sizeof(*ei)) {
708 ei = btrfs_item_ptr(leaf, path->slots[0],
709 struct btrfs_extent_item);
710 num_refs = btrfs_extent_refs(leaf, ei);
711 extent_flags = btrfs_extent_flags(leaf, ei);
713 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
714 struct btrfs_extent_item_v0 *ei0;
715 BUG_ON(item_size != sizeof(*ei0));
716 ei0 = btrfs_item_ptr(leaf, path->slots[0],
717 struct btrfs_extent_item_v0);
718 num_refs = btrfs_extent_refs_v0(leaf, ei0);
719 /* FIXME: this isn't correct for data */
720 extent_flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
725 BUG_ON(num_refs == 0);
735 delayed_refs = &trans->transaction->delayed_refs;
736 spin_lock(&delayed_refs->lock);
737 head = btrfs_find_delayed_ref_head(trans, bytenr);
739 if (!mutex_trylock(&head->mutex)) {
740 atomic_inc(&head->node.refs);
741 spin_unlock(&delayed_refs->lock);
743 btrfs_release_path(root->fs_info->extent_root, path);
745 mutex_lock(&head->mutex);
746 mutex_unlock(&head->mutex);
747 btrfs_put_delayed_ref(&head->node);
750 if (head->extent_op && head->extent_op->update_flags)
751 extent_flags |= head->extent_op->flags_to_set;
753 BUG_ON(num_refs == 0);
755 num_refs += head->node.ref_mod;
756 mutex_unlock(&head->mutex);
758 spin_unlock(&delayed_refs->lock);
760 WARN_ON(num_refs == 0);
764 *flags = extent_flags;
766 btrfs_free_path(path);
771 * Back reference rules. Back refs have three main goals:
773 * 1) differentiate between all holders of references to an extent so that
774 * when a reference is dropped we can make sure it was a valid reference
775 * before freeing the extent.
777 * 2) Provide enough information to quickly find the holders of an extent
778 * if we notice a given block is corrupted or bad.
780 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
781 * maintenance. This is actually the same as #2, but with a slightly
782 * different use case.
784 * There are two kinds of back refs. The implicit back refs is optimized
785 * for pointers in non-shared tree blocks. For a given pointer in a block,
786 * back refs of this kind provide information about the block's owner tree
787 * and the pointer's key. These information allow us to find the block by
788 * b-tree searching. The full back refs is for pointers in tree blocks not
789 * referenced by their owner trees. The location of tree block is recorded
790 * in the back refs. Actually the full back refs is generic, and can be
791 * used in all cases the implicit back refs is used. The major shortcoming
792 * of the full back refs is its overhead. Every time a tree block gets
793 * COWed, we have to update back refs entry for all pointers in it.
795 * For a newly allocated tree block, we use implicit back refs for
796 * pointers in it. This means most tree related operations only involve
797 * implicit back refs. For a tree block created in old transaction, the
798 * only way to drop a reference to it is COW it. So we can detect the
799 * event that tree block loses its owner tree's reference and do the
800 * back refs conversion.
802 * When a tree block is COW'd through a tree, there are four cases:
804 * The reference count of the block is one and the tree is the block's
805 * owner tree. Nothing to do in this case.
807 * The reference count of the block is one and the tree is not the
808 * block's owner tree. In this case, full back refs is used for pointers
809 * in the block. Remove these full back refs, add implicit back refs for
810 * every pointers in the new block.
812 * The reference count of the block is greater than one and the tree is
813 * the block's owner tree. In this case, implicit back refs is used for
814 * pointers in the block. Add full back refs for every pointers in the
815 * block, increase lower level extents' reference counts. The original
816 * implicit back refs are entailed to the new block.
818 * The reference count of the block is greater than one and the tree is
819 * not the block's owner tree. Add implicit back refs for every pointer in
820 * the new block, increase lower level extents' reference count.
822 * Back Reference Key composing:
824 * The key objectid corresponds to the first byte in the extent,
825 * The key type is used to differentiate between types of back refs.
826 * There are different meanings of the key offset for different types
829 * File extents can be referenced by:
831 * - multiple snapshots, subvolumes, or different generations in one subvol
832 * - different files inside a single subvolume
833 * - different offsets inside a file (bookend extents in file.c)
835 * The extent ref structure for the implicit back refs has fields for:
837 * - Objectid of the subvolume root
838 * - objectid of the file holding the reference
839 * - original offset in the file
840 * - how many bookend extents
842 * The key offset for the implicit back refs is hash of the first
845 * The extent ref structure for the full back refs has field for:
847 * - number of pointers in the tree leaf
849 * The key offset for the implicit back refs is the first byte of
852 * When a file extent is allocated, The implicit back refs is used.
853 * the fields are filled in:
855 * (root_key.objectid, inode objectid, offset in file, 1)
857 * When a file extent is removed file truncation, we find the
858 * corresponding implicit back refs and check the following fields:
860 * (btrfs_header_owner(leaf), inode objectid, offset in file)
862 * Btree extents can be referenced by:
864 * - Different subvolumes
866 * Both the implicit back refs and the full back refs for tree blocks
867 * only consist of key. The key offset for the implicit back refs is
868 * objectid of block's owner tree. The key offset for the full back refs
869 * is the first byte of parent block.
871 * When implicit back refs is used, information about the lowest key and
872 * level of the tree block are required. These information are stored in
873 * tree block info structure.
876 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
877 static int convert_extent_item_v0(struct btrfs_trans_handle *trans,
878 struct btrfs_root *root,
879 struct btrfs_path *path,
880 u64 owner, u32 extra_size)
882 struct btrfs_extent_item *item;
883 struct btrfs_extent_item_v0 *ei0;
884 struct btrfs_extent_ref_v0 *ref0;
885 struct btrfs_tree_block_info *bi;
886 struct extent_buffer *leaf;
887 struct btrfs_key key;
888 struct btrfs_key found_key;
889 u32 new_size = sizeof(*item);
893 leaf = path->nodes[0];
894 BUG_ON(btrfs_item_size_nr(leaf, path->slots[0]) != sizeof(*ei0));
896 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
897 ei0 = btrfs_item_ptr(leaf, path->slots[0],
898 struct btrfs_extent_item_v0);
899 refs = btrfs_extent_refs_v0(leaf, ei0);
901 if (owner == (u64)-1) {
903 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
904 ret = btrfs_next_leaf(root, path);
908 leaf = path->nodes[0];
910 btrfs_item_key_to_cpu(leaf, &found_key,
912 BUG_ON(key.objectid != found_key.objectid);
913 if (found_key.type != BTRFS_EXTENT_REF_V0_KEY) {
917 ref0 = btrfs_item_ptr(leaf, path->slots[0],
918 struct btrfs_extent_ref_v0);
919 owner = btrfs_ref_objectid_v0(leaf, ref0);
923 btrfs_release_path(root, path);
925 if (owner < BTRFS_FIRST_FREE_OBJECTID)
926 new_size += sizeof(*bi);
928 new_size -= sizeof(*ei0);
929 ret = btrfs_search_slot(trans, root, &key, path,
930 new_size + extra_size, 1);
935 ret = btrfs_extend_item(trans, root, path, new_size);
938 leaf = path->nodes[0];
939 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
940 btrfs_set_extent_refs(leaf, item, refs);
941 /* FIXME: get real generation */
942 btrfs_set_extent_generation(leaf, item, 0);
943 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
944 btrfs_set_extent_flags(leaf, item,
945 BTRFS_EXTENT_FLAG_TREE_BLOCK |
946 BTRFS_BLOCK_FLAG_FULL_BACKREF);
947 bi = (struct btrfs_tree_block_info *)(item + 1);
948 /* FIXME: get first key of the block */
949 memset_extent_buffer(leaf, 0, (unsigned long)bi, sizeof(*bi));
950 btrfs_set_tree_block_level(leaf, bi, (int)owner);
952 btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_DATA);
954 btrfs_mark_buffer_dirty(leaf);
959 static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
961 u32 high_crc = ~(u32)0;
962 u32 low_crc = ~(u32)0;
965 lenum = cpu_to_le64(root_objectid);
966 high_crc = crc32c(high_crc, &lenum, sizeof(lenum));
967 lenum = cpu_to_le64(owner);
968 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
969 lenum = cpu_to_le64(offset);
970 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
972 return ((u64)high_crc << 31) ^ (u64)low_crc;
975 static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
976 struct btrfs_extent_data_ref *ref)
978 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
979 btrfs_extent_data_ref_objectid(leaf, ref),
980 btrfs_extent_data_ref_offset(leaf, ref));
983 static int match_extent_data_ref(struct extent_buffer *leaf,
984 struct btrfs_extent_data_ref *ref,
985 u64 root_objectid, u64 owner, u64 offset)
987 if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
988 btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
989 btrfs_extent_data_ref_offset(leaf, ref) != offset)
994 static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
995 struct btrfs_root *root,
996 struct btrfs_path *path,
997 u64 bytenr, u64 parent,
999 u64 owner, u64 offset)
1001 struct btrfs_key key;
1002 struct btrfs_extent_data_ref *ref;
1003 struct extent_buffer *leaf;
1009 key.objectid = bytenr;
1011 key.type = BTRFS_SHARED_DATA_REF_KEY;
1012 key.offset = parent;
1014 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1015 key.offset = hash_extent_data_ref(root_objectid,
1020 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1029 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1030 key.type = BTRFS_EXTENT_REF_V0_KEY;
1031 btrfs_release_path(root, path);
1032 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1043 leaf = path->nodes[0];
1044 nritems = btrfs_header_nritems(leaf);
1046 if (path->slots[0] >= nritems) {
1047 ret = btrfs_next_leaf(root, path);
1053 leaf = path->nodes[0];
1054 nritems = btrfs_header_nritems(leaf);
1058 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1059 if (key.objectid != bytenr ||
1060 key.type != BTRFS_EXTENT_DATA_REF_KEY)
1063 ref = btrfs_item_ptr(leaf, path->slots[0],
1064 struct btrfs_extent_data_ref);
1066 if (match_extent_data_ref(leaf, ref, root_objectid,
1069 btrfs_release_path(root, path);
1081 static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
1082 struct btrfs_root *root,
1083 struct btrfs_path *path,
1084 u64 bytenr, u64 parent,
1085 u64 root_objectid, u64 owner,
1086 u64 offset, int refs_to_add)
1088 struct btrfs_key key;
1089 struct extent_buffer *leaf;
1094 key.objectid = bytenr;
1096 key.type = BTRFS_SHARED_DATA_REF_KEY;
1097 key.offset = parent;
1098 size = sizeof(struct btrfs_shared_data_ref);
1100 key.type = BTRFS_EXTENT_DATA_REF_KEY;
1101 key.offset = hash_extent_data_ref(root_objectid,
1103 size = sizeof(struct btrfs_extent_data_ref);
1106 ret = btrfs_insert_empty_item(trans, root, path, &key, size);
1107 if (ret && ret != -EEXIST)
1110 leaf = path->nodes[0];
1112 struct btrfs_shared_data_ref *ref;
1113 ref = btrfs_item_ptr(leaf, path->slots[0],
1114 struct btrfs_shared_data_ref);
1116 btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
1118 num_refs = btrfs_shared_data_ref_count(leaf, ref);
1119 num_refs += refs_to_add;
1120 btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
1123 struct btrfs_extent_data_ref *ref;
1124 while (ret == -EEXIST) {
1125 ref = btrfs_item_ptr(leaf, path->slots[0],
1126 struct btrfs_extent_data_ref);
1127 if (match_extent_data_ref(leaf, ref, root_objectid,
1130 btrfs_release_path(root, path);
1132 ret = btrfs_insert_empty_item(trans, root, path, &key,
1134 if (ret && ret != -EEXIST)
1137 leaf = path->nodes[0];
1139 ref = btrfs_item_ptr(leaf, path->slots[0],
1140 struct btrfs_extent_data_ref);
1142 btrfs_set_extent_data_ref_root(leaf, ref,
1144 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
1145 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
1146 btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
1148 num_refs = btrfs_extent_data_ref_count(leaf, ref);
1149 num_refs += refs_to_add;
1150 btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
1153 btrfs_mark_buffer_dirty(leaf);
1156 btrfs_release_path(root, path);
1160 static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
1161 struct btrfs_root *root,
1162 struct btrfs_path *path,
1165 struct btrfs_key key;
1166 struct btrfs_extent_data_ref *ref1 = NULL;
1167 struct btrfs_shared_data_ref *ref2 = NULL;
1168 struct extent_buffer *leaf;
1172 leaf = path->nodes[0];
1173 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1175 if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1176 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1177 struct btrfs_extent_data_ref);
1178 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1179 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1180 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1181 struct btrfs_shared_data_ref);
1182 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1183 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1184 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1185 struct btrfs_extent_ref_v0 *ref0;
1186 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1187 struct btrfs_extent_ref_v0);
1188 num_refs = btrfs_ref_count_v0(leaf, ref0);
1194 BUG_ON(num_refs < refs_to_drop);
1195 num_refs -= refs_to_drop;
1197 if (num_refs == 0) {
1198 ret = btrfs_del_item(trans, root, path);
1200 if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
1201 btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
1202 else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
1203 btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
1204 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1206 struct btrfs_extent_ref_v0 *ref0;
1207 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1208 struct btrfs_extent_ref_v0);
1209 btrfs_set_ref_count_v0(leaf, ref0, num_refs);
1212 btrfs_mark_buffer_dirty(leaf);
1217 static noinline u32 extent_data_ref_count(struct btrfs_root *root,
1218 struct btrfs_path *path,
1219 struct btrfs_extent_inline_ref *iref)
1221 struct btrfs_key key;
1222 struct extent_buffer *leaf;
1223 struct btrfs_extent_data_ref *ref1;
1224 struct btrfs_shared_data_ref *ref2;
1227 leaf = path->nodes[0];
1228 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1230 if (btrfs_extent_inline_ref_type(leaf, iref) ==
1231 BTRFS_EXTENT_DATA_REF_KEY) {
1232 ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
1233 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1235 ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
1236 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1238 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1239 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1240 struct btrfs_extent_data_ref);
1241 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1242 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1243 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1244 struct btrfs_shared_data_ref);
1245 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1246 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1247 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1248 struct btrfs_extent_ref_v0 *ref0;
1249 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1250 struct btrfs_extent_ref_v0);
1251 num_refs = btrfs_ref_count_v0(leaf, ref0);
1259 static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
1260 struct btrfs_root *root,
1261 struct btrfs_path *path,
1262 u64 bytenr, u64 parent,
1265 struct btrfs_key key;
1268 key.objectid = bytenr;
1270 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1271 key.offset = parent;
1273 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1274 key.offset = root_objectid;
1277 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1280 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1281 if (ret == -ENOENT && parent) {
1282 btrfs_release_path(root, path);
1283 key.type = BTRFS_EXTENT_REF_V0_KEY;
1284 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1292 static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
1293 struct btrfs_root *root,
1294 struct btrfs_path *path,
1295 u64 bytenr, u64 parent,
1298 struct btrfs_key key;
1301 key.objectid = bytenr;
1303 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1304 key.offset = parent;
1306 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1307 key.offset = root_objectid;
1310 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1311 btrfs_release_path(root, path);
1315 static inline int extent_ref_type(u64 parent, u64 owner)
1318 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1320 type = BTRFS_SHARED_BLOCK_REF_KEY;
1322 type = BTRFS_TREE_BLOCK_REF_KEY;
1325 type = BTRFS_SHARED_DATA_REF_KEY;
1327 type = BTRFS_EXTENT_DATA_REF_KEY;
1332 static int find_next_key(struct btrfs_path *path, int level,
1333 struct btrfs_key *key)
1336 for (; level < BTRFS_MAX_LEVEL; level++) {
1337 if (!path->nodes[level])
1339 if (path->slots[level] + 1 >=
1340 btrfs_header_nritems(path->nodes[level]))
1343 btrfs_item_key_to_cpu(path->nodes[level], key,
1344 path->slots[level] + 1);
1346 btrfs_node_key_to_cpu(path->nodes[level], key,
1347 path->slots[level] + 1);
1354 * look for inline back ref. if back ref is found, *ref_ret is set
1355 * to the address of inline back ref, and 0 is returned.
1357 * if back ref isn't found, *ref_ret is set to the address where it
1358 * should be inserted, and -ENOENT is returned.
1360 * if insert is true and there are too many inline back refs, the path
1361 * points to the extent item, and -EAGAIN is returned.
1363 * NOTE: inline back refs are ordered in the same way that back ref
1364 * items in the tree are ordered.
1366 static noinline_for_stack
1367 int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
1368 struct btrfs_root *root,
1369 struct btrfs_path *path,
1370 struct btrfs_extent_inline_ref **ref_ret,
1371 u64 bytenr, u64 num_bytes,
1372 u64 parent, u64 root_objectid,
1373 u64 owner, u64 offset, int insert)
1375 struct btrfs_key key;
1376 struct extent_buffer *leaf;
1377 struct btrfs_extent_item *ei;
1378 struct btrfs_extent_inline_ref *iref;
1389 key.objectid = bytenr;
1390 key.type = BTRFS_EXTENT_ITEM_KEY;
1391 key.offset = num_bytes;
1393 want = extent_ref_type(parent, owner);
1395 extra_size = btrfs_extent_inline_ref_size(want);
1396 path->keep_locks = 1;
1399 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
1406 leaf = path->nodes[0];
1407 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1408 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1409 if (item_size < sizeof(*ei)) {
1414 ret = convert_extent_item_v0(trans, root, path, owner,
1420 leaf = path->nodes[0];
1421 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1424 BUG_ON(item_size < sizeof(*ei));
1426 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1427 flags = btrfs_extent_flags(leaf, ei);
1429 ptr = (unsigned long)(ei + 1);
1430 end = (unsigned long)ei + item_size;
1432 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
1433 ptr += sizeof(struct btrfs_tree_block_info);
1436 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_DATA));
1445 iref = (struct btrfs_extent_inline_ref *)ptr;
1446 type = btrfs_extent_inline_ref_type(leaf, iref);
1450 ptr += btrfs_extent_inline_ref_size(type);
1454 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1455 struct btrfs_extent_data_ref *dref;
1456 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1457 if (match_extent_data_ref(leaf, dref, root_objectid,
1462 if (hash_extent_data_ref_item(leaf, dref) <
1463 hash_extent_data_ref(root_objectid, owner, offset))
1467 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1469 if (parent == ref_offset) {
1473 if (ref_offset < parent)
1476 if (root_objectid == ref_offset) {
1480 if (ref_offset < root_objectid)
1484 ptr += btrfs_extent_inline_ref_size(type);
1486 if (err == -ENOENT && insert) {
1487 if (item_size + extra_size >=
1488 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
1493 * To add new inline back ref, we have to make sure
1494 * there is no corresponding back ref item.
1495 * For simplicity, we just do not add new inline back
1496 * ref if there is any kind of item for this block
1498 if (find_next_key(path, 0, &key) == 0 &&
1499 key.objectid == bytenr &&
1500 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
1505 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
1508 path->keep_locks = 0;
1509 btrfs_unlock_up_safe(path, 1);
1515 * helper to add new inline back ref
1517 static noinline_for_stack
1518 int setup_inline_extent_backref(struct btrfs_trans_handle *trans,
1519 struct btrfs_root *root,
1520 struct btrfs_path *path,
1521 struct btrfs_extent_inline_ref *iref,
1522 u64 parent, u64 root_objectid,
1523 u64 owner, u64 offset, int refs_to_add,
1524 struct btrfs_delayed_extent_op *extent_op)
1526 struct extent_buffer *leaf;
1527 struct btrfs_extent_item *ei;
1530 unsigned long item_offset;
1536 leaf = path->nodes[0];
1537 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1538 item_offset = (unsigned long)iref - (unsigned long)ei;
1540 type = extent_ref_type(parent, owner);
1541 size = btrfs_extent_inline_ref_size(type);
1543 ret = btrfs_extend_item(trans, root, path, size);
1546 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1547 refs = btrfs_extent_refs(leaf, ei);
1548 refs += refs_to_add;
1549 btrfs_set_extent_refs(leaf, ei, refs);
1551 __run_delayed_extent_op(extent_op, leaf, ei);
1553 ptr = (unsigned long)ei + item_offset;
1554 end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
1555 if (ptr < end - size)
1556 memmove_extent_buffer(leaf, ptr + size, ptr,
1559 iref = (struct btrfs_extent_inline_ref *)ptr;
1560 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1561 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1562 struct btrfs_extent_data_ref *dref;
1563 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1564 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1565 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1566 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1567 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1568 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1569 struct btrfs_shared_data_ref *sref;
1570 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1571 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1572 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1573 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1574 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1576 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1578 btrfs_mark_buffer_dirty(leaf);
1582 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1583 struct btrfs_root *root,
1584 struct btrfs_path *path,
1585 struct btrfs_extent_inline_ref **ref_ret,
1586 u64 bytenr, u64 num_bytes, u64 parent,
1587 u64 root_objectid, u64 owner, u64 offset)
1591 ret = lookup_inline_extent_backref(trans, root, path, ref_ret,
1592 bytenr, num_bytes, parent,
1593 root_objectid, owner, offset, 0);
1597 btrfs_release_path(root, path);
1600 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1601 ret = lookup_tree_block_ref(trans, root, path, bytenr, parent,
1604 ret = lookup_extent_data_ref(trans, root, path, bytenr, parent,
1605 root_objectid, owner, offset);
1611 * helper to update/remove inline back ref
1613 static noinline_for_stack
1614 int update_inline_extent_backref(struct btrfs_trans_handle *trans,
1615 struct btrfs_root *root,
1616 struct btrfs_path *path,
1617 struct btrfs_extent_inline_ref *iref,
1619 struct btrfs_delayed_extent_op *extent_op)
1621 struct extent_buffer *leaf;
1622 struct btrfs_extent_item *ei;
1623 struct btrfs_extent_data_ref *dref = NULL;
1624 struct btrfs_shared_data_ref *sref = NULL;
1633 leaf = path->nodes[0];
1634 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1635 refs = btrfs_extent_refs(leaf, ei);
1636 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1637 refs += refs_to_mod;
1638 btrfs_set_extent_refs(leaf, ei, refs);
1640 __run_delayed_extent_op(extent_op, leaf, ei);
1642 type = btrfs_extent_inline_ref_type(leaf, iref);
1644 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1645 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1646 refs = btrfs_extent_data_ref_count(leaf, dref);
1647 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1648 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1649 refs = btrfs_shared_data_ref_count(leaf, sref);
1652 BUG_ON(refs_to_mod != -1);
1655 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1656 refs += refs_to_mod;
1659 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1660 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1662 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1664 size = btrfs_extent_inline_ref_size(type);
1665 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1666 ptr = (unsigned long)iref;
1667 end = (unsigned long)ei + item_size;
1668 if (ptr + size < end)
1669 memmove_extent_buffer(leaf, ptr, ptr + size,
1672 ret = btrfs_truncate_item(trans, root, path, item_size, 1);
1675 btrfs_mark_buffer_dirty(leaf);
1679 static noinline_for_stack
1680 int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1681 struct btrfs_root *root,
1682 struct btrfs_path *path,
1683 u64 bytenr, u64 num_bytes, u64 parent,
1684 u64 root_objectid, u64 owner,
1685 u64 offset, int refs_to_add,
1686 struct btrfs_delayed_extent_op *extent_op)
1688 struct btrfs_extent_inline_ref *iref;
1691 ret = lookup_inline_extent_backref(trans, root, path, &iref,
1692 bytenr, num_bytes, parent,
1693 root_objectid, owner, offset, 1);
1695 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
1696 ret = update_inline_extent_backref(trans, root, path, iref,
1697 refs_to_add, extent_op);
1698 } else if (ret == -ENOENT) {
1699 ret = setup_inline_extent_backref(trans, root, path, iref,
1700 parent, root_objectid,
1701 owner, offset, refs_to_add,
1707 static int insert_extent_backref(struct btrfs_trans_handle *trans,
1708 struct btrfs_root *root,
1709 struct btrfs_path *path,
1710 u64 bytenr, u64 parent, u64 root_objectid,
1711 u64 owner, u64 offset, int refs_to_add)
1714 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1715 BUG_ON(refs_to_add != 1);
1716 ret = insert_tree_block_ref(trans, root, path, bytenr,
1717 parent, root_objectid);
1719 ret = insert_extent_data_ref(trans, root, path, bytenr,
1720 parent, root_objectid,
1721 owner, offset, refs_to_add);
1726 static int remove_extent_backref(struct btrfs_trans_handle *trans,
1727 struct btrfs_root *root,
1728 struct btrfs_path *path,
1729 struct btrfs_extent_inline_ref *iref,
1730 int refs_to_drop, int is_data)
1734 BUG_ON(!is_data && refs_to_drop != 1);
1736 ret = update_inline_extent_backref(trans, root, path, iref,
1737 -refs_to_drop, NULL);
1738 } else if (is_data) {
1739 ret = remove_extent_data_ref(trans, root, path, refs_to_drop);
1741 ret = btrfs_del_item(trans, root, path);
1746 static void btrfs_issue_discard(struct block_device *bdev,
1749 blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_KERNEL,
1750 BLKDEV_IFL_WAIT | BLKDEV_IFL_BARRIER);
1753 static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
1757 u64 map_length = num_bytes;
1758 struct btrfs_multi_bio *multi = NULL;
1760 if (!btrfs_test_opt(root, DISCARD))
1763 /* Tell the block device(s) that the sectors can be discarded */
1764 ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
1765 bytenr, &map_length, &multi, 0);
1767 struct btrfs_bio_stripe *stripe = multi->stripes;
1770 if (map_length > num_bytes)
1771 map_length = num_bytes;
1773 for (i = 0; i < multi->num_stripes; i++, stripe++) {
1774 btrfs_issue_discard(stripe->dev->bdev,
1784 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1785 struct btrfs_root *root,
1786 u64 bytenr, u64 num_bytes, u64 parent,
1787 u64 root_objectid, u64 owner, u64 offset)
1790 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID &&
1791 root_objectid == BTRFS_TREE_LOG_OBJECTID);
1793 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1794 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
1795 parent, root_objectid, (int)owner,
1796 BTRFS_ADD_DELAYED_REF, NULL);
1798 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
1799 parent, root_objectid, owner, offset,
1800 BTRFS_ADD_DELAYED_REF, NULL);
1805 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1806 struct btrfs_root *root,
1807 u64 bytenr, u64 num_bytes,
1808 u64 parent, u64 root_objectid,
1809 u64 owner, u64 offset, int refs_to_add,
1810 struct btrfs_delayed_extent_op *extent_op)
1812 struct btrfs_path *path;
1813 struct extent_buffer *leaf;
1814 struct btrfs_extent_item *item;
1819 path = btrfs_alloc_path();
1824 path->leave_spinning = 1;
1825 /* this will setup the path even if it fails to insert the back ref */
1826 ret = insert_inline_extent_backref(trans, root->fs_info->extent_root,
1827 path, bytenr, num_bytes, parent,
1828 root_objectid, owner, offset,
1829 refs_to_add, extent_op);
1833 if (ret != -EAGAIN) {
1838 leaf = path->nodes[0];
1839 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1840 refs = btrfs_extent_refs(leaf, item);
1841 btrfs_set_extent_refs(leaf, item, refs + refs_to_add);
1843 __run_delayed_extent_op(extent_op, leaf, item);
1845 btrfs_mark_buffer_dirty(leaf);
1846 btrfs_release_path(root->fs_info->extent_root, path);
1849 path->leave_spinning = 1;
1851 /* now insert the actual backref */
1852 ret = insert_extent_backref(trans, root->fs_info->extent_root,
1853 path, bytenr, parent, root_objectid,
1854 owner, offset, refs_to_add);
1857 btrfs_free_path(path);
1861 static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
1862 struct btrfs_root *root,
1863 struct btrfs_delayed_ref_node *node,
1864 struct btrfs_delayed_extent_op *extent_op,
1865 int insert_reserved)
1868 struct btrfs_delayed_data_ref *ref;
1869 struct btrfs_key ins;
1874 ins.objectid = node->bytenr;
1875 ins.offset = node->num_bytes;
1876 ins.type = BTRFS_EXTENT_ITEM_KEY;
1878 ref = btrfs_delayed_node_to_data_ref(node);
1879 if (node->type == BTRFS_SHARED_DATA_REF_KEY)
1880 parent = ref->parent;
1882 ref_root = ref->root;
1884 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
1886 BUG_ON(extent_op->update_key);
1887 flags |= extent_op->flags_to_set;
1889 ret = alloc_reserved_file_extent(trans, root,
1890 parent, ref_root, flags,
1891 ref->objectid, ref->offset,
1892 &ins, node->ref_mod);
1893 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
1894 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
1895 node->num_bytes, parent,
1896 ref_root, ref->objectid,
1897 ref->offset, node->ref_mod,
1899 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
1900 ret = __btrfs_free_extent(trans, root, node->bytenr,
1901 node->num_bytes, parent,
1902 ref_root, ref->objectid,
1903 ref->offset, node->ref_mod,
1911 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
1912 struct extent_buffer *leaf,
1913 struct btrfs_extent_item *ei)
1915 u64 flags = btrfs_extent_flags(leaf, ei);
1916 if (extent_op->update_flags) {
1917 flags |= extent_op->flags_to_set;
1918 btrfs_set_extent_flags(leaf, ei, flags);
1921 if (extent_op->update_key) {
1922 struct btrfs_tree_block_info *bi;
1923 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK));
1924 bi = (struct btrfs_tree_block_info *)(ei + 1);
1925 btrfs_set_tree_block_key(leaf, bi, &extent_op->key);
1929 static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
1930 struct btrfs_root *root,
1931 struct btrfs_delayed_ref_node *node,
1932 struct btrfs_delayed_extent_op *extent_op)
1934 struct btrfs_key key;
1935 struct btrfs_path *path;
1936 struct btrfs_extent_item *ei;
1937 struct extent_buffer *leaf;
1942 path = btrfs_alloc_path();
1946 key.objectid = node->bytenr;
1947 key.type = BTRFS_EXTENT_ITEM_KEY;
1948 key.offset = node->num_bytes;
1951 path->leave_spinning = 1;
1952 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key,
1963 leaf = path->nodes[0];
1964 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1965 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1966 if (item_size < sizeof(*ei)) {
1967 ret = convert_extent_item_v0(trans, root->fs_info->extent_root,
1973 leaf = path->nodes[0];
1974 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1977 BUG_ON(item_size < sizeof(*ei));
1978 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1979 __run_delayed_extent_op(extent_op, leaf, ei);
1981 btrfs_mark_buffer_dirty(leaf);
1983 btrfs_free_path(path);
1987 static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
1988 struct btrfs_root *root,
1989 struct btrfs_delayed_ref_node *node,
1990 struct btrfs_delayed_extent_op *extent_op,
1991 int insert_reserved)
1994 struct btrfs_delayed_tree_ref *ref;
1995 struct btrfs_key ins;
1999 ins.objectid = node->bytenr;
2000 ins.offset = node->num_bytes;
2001 ins.type = BTRFS_EXTENT_ITEM_KEY;
2003 ref = btrfs_delayed_node_to_tree_ref(node);
2004 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2005 parent = ref->parent;
2007 ref_root = ref->root;
2009 BUG_ON(node->ref_mod != 1);
2010 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
2011 BUG_ON(!extent_op || !extent_op->update_flags ||
2012 !extent_op->update_key);
2013 ret = alloc_reserved_tree_block(trans, root,
2015 extent_op->flags_to_set,
2018 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
2019 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
2020 node->num_bytes, parent, ref_root,
2021 ref->level, 0, 1, extent_op);
2022 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
2023 ret = __btrfs_free_extent(trans, root, node->bytenr,
2024 node->num_bytes, parent, ref_root,
2025 ref->level, 0, 1, extent_op);
2032 /* helper function to actually process a single delayed ref entry */
2033 static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
2034 struct btrfs_root *root,
2035 struct btrfs_delayed_ref_node *node,
2036 struct btrfs_delayed_extent_op *extent_op,
2037 int insert_reserved)
2040 if (btrfs_delayed_ref_is_head(node)) {
2041 struct btrfs_delayed_ref_head *head;
2043 * we've hit the end of the chain and we were supposed
2044 * to insert this extent into the tree. But, it got
2045 * deleted before we ever needed to insert it, so all
2046 * we have to do is clean up the accounting
2049 head = btrfs_delayed_node_to_head(node);
2050 if (insert_reserved) {
2051 btrfs_pin_extent(root, node->bytenr,
2052 node->num_bytes, 1);
2053 if (head->is_data) {
2054 ret = btrfs_del_csums(trans, root,
2060 mutex_unlock(&head->mutex);
2064 if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
2065 node->type == BTRFS_SHARED_BLOCK_REF_KEY)
2066 ret = run_delayed_tree_ref(trans, root, node, extent_op,
2068 else if (node->type == BTRFS_EXTENT_DATA_REF_KEY ||
2069 node->type == BTRFS_SHARED_DATA_REF_KEY)
2070 ret = run_delayed_data_ref(trans, root, node, extent_op,
2077 static noinline struct btrfs_delayed_ref_node *
2078 select_delayed_ref(struct btrfs_delayed_ref_head *head)
2080 struct rb_node *node;
2081 struct btrfs_delayed_ref_node *ref;
2082 int action = BTRFS_ADD_DELAYED_REF;
2085 * select delayed ref of type BTRFS_ADD_DELAYED_REF first.
2086 * this prevents ref count from going down to zero when
2087 * there still are pending delayed ref.
2089 node = rb_prev(&head->node.rb_node);
2093 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2095 if (ref->bytenr != head->node.bytenr)
2097 if (ref->action == action)
2099 node = rb_prev(node);
2101 if (action == BTRFS_ADD_DELAYED_REF) {
2102 action = BTRFS_DROP_DELAYED_REF;
2108 static noinline int run_clustered_refs(struct btrfs_trans_handle *trans,
2109 struct btrfs_root *root,
2110 struct list_head *cluster)
2112 struct btrfs_delayed_ref_root *delayed_refs;
2113 struct btrfs_delayed_ref_node *ref;
2114 struct btrfs_delayed_ref_head *locked_ref = NULL;
2115 struct btrfs_delayed_extent_op *extent_op;
2118 int must_insert_reserved = 0;
2120 delayed_refs = &trans->transaction->delayed_refs;
2123 /* pick a new head ref from the cluster list */
2124 if (list_empty(cluster))
2127 locked_ref = list_entry(cluster->next,
2128 struct btrfs_delayed_ref_head, cluster);
2130 /* grab the lock that says we are going to process
2131 * all the refs for this head */
2132 ret = btrfs_delayed_ref_lock(trans, locked_ref);
2135 * we may have dropped the spin lock to get the head
2136 * mutex lock, and that might have given someone else
2137 * time to free the head. If that's true, it has been
2138 * removed from our list and we can move on.
2140 if (ret == -EAGAIN) {
2148 * record the must insert reserved flag before we
2149 * drop the spin lock.
2151 must_insert_reserved = locked_ref->must_insert_reserved;
2152 locked_ref->must_insert_reserved = 0;
2154 extent_op = locked_ref->extent_op;
2155 locked_ref->extent_op = NULL;
2158 * locked_ref is the head node, so we have to go one
2159 * node back for any delayed ref updates
2161 ref = select_delayed_ref(locked_ref);
2163 /* All delayed refs have been processed, Go ahead
2164 * and send the head node to run_one_delayed_ref,
2165 * so that any accounting fixes can happen
2167 ref = &locked_ref->node;
2169 if (extent_op && must_insert_reserved) {
2175 spin_unlock(&delayed_refs->lock);
2177 ret = run_delayed_extent_op(trans, root,
2183 spin_lock(&delayed_refs->lock);
2187 list_del_init(&locked_ref->cluster);
2192 rb_erase(&ref->rb_node, &delayed_refs->root);
2193 delayed_refs->num_entries--;
2195 spin_unlock(&delayed_refs->lock);
2197 ret = run_one_delayed_ref(trans, root, ref, extent_op,
2198 must_insert_reserved);
2201 btrfs_put_delayed_ref(ref);
2206 spin_lock(&delayed_refs->lock);
2212 * this starts processing the delayed reference count updates and
2213 * extent insertions we have queued up so far. count can be
2214 * 0, which means to process everything in the tree at the start
2215 * of the run (but not newly added entries), or it can be some target
2216 * number you'd like to process.
2218 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2219 struct btrfs_root *root, unsigned long count)
2221 struct rb_node *node;
2222 struct btrfs_delayed_ref_root *delayed_refs;
2223 struct btrfs_delayed_ref_node *ref;
2224 struct list_head cluster;
2226 int run_all = count == (unsigned long)-1;
2229 if (root == root->fs_info->extent_root)
2230 root = root->fs_info->tree_root;
2232 delayed_refs = &trans->transaction->delayed_refs;
2233 INIT_LIST_HEAD(&cluster);
2235 spin_lock(&delayed_refs->lock);
2237 count = delayed_refs->num_entries * 2;
2241 if (!(run_all || run_most) &&
2242 delayed_refs->num_heads_ready < 64)
2246 * go find something we can process in the rbtree. We start at
2247 * the beginning of the tree, and then build a cluster
2248 * of refs to process starting at the first one we are able to
2251 ret = btrfs_find_ref_cluster(trans, &cluster,
2252 delayed_refs->run_delayed_start);
2256 ret = run_clustered_refs(trans, root, &cluster);
2259 count -= min_t(unsigned long, ret, count);
2266 node = rb_first(&delayed_refs->root);
2269 count = (unsigned long)-1;
2272 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2274 if (btrfs_delayed_ref_is_head(ref)) {
2275 struct btrfs_delayed_ref_head *head;
2277 head = btrfs_delayed_node_to_head(ref);
2278 atomic_inc(&ref->refs);
2280 spin_unlock(&delayed_refs->lock);
2281 mutex_lock(&head->mutex);
2282 mutex_unlock(&head->mutex);
2284 btrfs_put_delayed_ref(ref);
2288 node = rb_next(node);
2290 spin_unlock(&delayed_refs->lock);
2291 schedule_timeout(1);
2295 spin_unlock(&delayed_refs->lock);
2299 int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
2300 struct btrfs_root *root,
2301 u64 bytenr, u64 num_bytes, u64 flags,
2304 struct btrfs_delayed_extent_op *extent_op;
2307 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
2311 extent_op->flags_to_set = flags;
2312 extent_op->update_flags = 1;
2313 extent_op->update_key = 0;
2314 extent_op->is_data = is_data ? 1 : 0;
2316 ret = btrfs_add_delayed_extent_op(trans, bytenr, num_bytes, extent_op);
2322 static noinline int check_delayed_ref(struct btrfs_trans_handle *trans,
2323 struct btrfs_root *root,
2324 struct btrfs_path *path,
2325 u64 objectid, u64 offset, u64 bytenr)
2327 struct btrfs_delayed_ref_head *head;
2328 struct btrfs_delayed_ref_node *ref;
2329 struct btrfs_delayed_data_ref *data_ref;
2330 struct btrfs_delayed_ref_root *delayed_refs;
2331 struct rb_node *node;
2335 delayed_refs = &trans->transaction->delayed_refs;
2336 spin_lock(&delayed_refs->lock);
2337 head = btrfs_find_delayed_ref_head(trans, bytenr);
2341 if (!mutex_trylock(&head->mutex)) {
2342 atomic_inc(&head->node.refs);
2343 spin_unlock(&delayed_refs->lock);
2345 btrfs_release_path(root->fs_info->extent_root, path);
2347 mutex_lock(&head->mutex);
2348 mutex_unlock(&head->mutex);
2349 btrfs_put_delayed_ref(&head->node);
2353 node = rb_prev(&head->node.rb_node);
2357 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2359 if (ref->bytenr != bytenr)
2363 if (ref->type != BTRFS_EXTENT_DATA_REF_KEY)
2366 data_ref = btrfs_delayed_node_to_data_ref(ref);
2368 node = rb_prev(node);
2370 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2371 if (ref->bytenr == bytenr)
2375 if (data_ref->root != root->root_key.objectid ||
2376 data_ref->objectid != objectid || data_ref->offset != offset)
2381 mutex_unlock(&head->mutex);
2383 spin_unlock(&delayed_refs->lock);
2387 static noinline int check_committed_ref(struct btrfs_trans_handle *trans,
2388 struct btrfs_root *root,
2389 struct btrfs_path *path,
2390 u64 objectid, u64 offset, u64 bytenr)
2392 struct btrfs_root *extent_root = root->fs_info->extent_root;
2393 struct extent_buffer *leaf;
2394 struct btrfs_extent_data_ref *ref;
2395 struct btrfs_extent_inline_ref *iref;
2396 struct btrfs_extent_item *ei;
2397 struct btrfs_key key;
2401 key.objectid = bytenr;
2402 key.offset = (u64)-1;
2403 key.type = BTRFS_EXTENT_ITEM_KEY;
2405 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
2411 if (path->slots[0] == 0)
2415 leaf = path->nodes[0];
2416 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2418 if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY)
2422 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2423 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2424 if (item_size < sizeof(*ei)) {
2425 WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0));
2429 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2431 if (item_size != sizeof(*ei) +
2432 btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY))
2435 if (btrfs_extent_generation(leaf, ei) <=
2436 btrfs_root_last_snapshot(&root->root_item))
2439 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
2440 if (btrfs_extent_inline_ref_type(leaf, iref) !=
2441 BTRFS_EXTENT_DATA_REF_KEY)
2444 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
2445 if (btrfs_extent_refs(leaf, ei) !=
2446 btrfs_extent_data_ref_count(leaf, ref) ||
2447 btrfs_extent_data_ref_root(leaf, ref) !=
2448 root->root_key.objectid ||
2449 btrfs_extent_data_ref_objectid(leaf, ref) != objectid ||
2450 btrfs_extent_data_ref_offset(leaf, ref) != offset)
2458 int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans,
2459 struct btrfs_root *root,
2460 u64 objectid, u64 offset, u64 bytenr)
2462 struct btrfs_path *path;
2466 path = btrfs_alloc_path();
2471 ret = check_committed_ref(trans, root, path, objectid,
2473 if (ret && ret != -ENOENT)
2476 ret2 = check_delayed_ref(trans, root, path, objectid,
2478 } while (ret2 == -EAGAIN);
2480 if (ret2 && ret2 != -ENOENT) {
2485 if (ret != -ENOENT || ret2 != -ENOENT)
2488 btrfs_free_path(path);
2489 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
2495 int btrfs_cache_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2496 struct extent_buffer *buf, u32 nr_extents)
2498 struct btrfs_key key;
2499 struct btrfs_file_extent_item *fi;
2507 if (!root->ref_cows)
2510 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
2512 root_gen = root->root_key.offset;
2515 root_gen = trans->transid - 1;
2518 level = btrfs_header_level(buf);
2519 nritems = btrfs_header_nritems(buf);
2522 struct btrfs_leaf_ref *ref;
2523 struct btrfs_extent_info *info;
2525 ref = btrfs_alloc_leaf_ref(root, nr_extents);
2531 ref->root_gen = root_gen;
2532 ref->bytenr = buf->start;
2533 ref->owner = btrfs_header_owner(buf);
2534 ref->generation = btrfs_header_generation(buf);
2535 ref->nritems = nr_extents;
2536 info = ref->extents;
2538 for (i = 0; nr_extents > 0 && i < nritems; i++) {
2540 btrfs_item_key_to_cpu(buf, &key, i);
2541 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2543 fi = btrfs_item_ptr(buf, i,
2544 struct btrfs_file_extent_item);
2545 if (btrfs_file_extent_type(buf, fi) ==
2546 BTRFS_FILE_EXTENT_INLINE)
2548 disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2549 if (disk_bytenr == 0)
2552 info->bytenr = disk_bytenr;
2554 btrfs_file_extent_disk_num_bytes(buf, fi);
2555 info->objectid = key.objectid;
2556 info->offset = key.offset;
2560 ret = btrfs_add_leaf_ref(root, ref, shared);
2561 if (ret == -EEXIST && shared) {
2562 struct btrfs_leaf_ref *old;
2563 old = btrfs_lookup_leaf_ref(root, ref->bytenr);
2565 btrfs_remove_leaf_ref(root, old);
2566 btrfs_free_leaf_ref(root, old);
2567 ret = btrfs_add_leaf_ref(root, ref, shared);
2570 btrfs_free_leaf_ref(root, ref);
2576 /* when a block goes through cow, we update the reference counts of
2577 * everything that block points to. The internal pointers of the block
2578 * can be in just about any order, and it is likely to have clusters of
2579 * things that are close together and clusters of things that are not.
2581 * To help reduce the seeks that come with updating all of these reference
2582 * counts, sort them by byte number before actual updates are done.
2584 * struct refsort is used to match byte number to slot in the btree block.
2585 * we sort based on the byte number and then use the slot to actually
2588 * struct refsort is smaller than strcut btrfs_item and smaller than
2589 * struct btrfs_key_ptr. Since we're currently limited to the page size
2590 * for a btree block, there's no way for a kmalloc of refsorts for a
2591 * single node to be bigger than a page.
2599 * for passing into sort()
2601 static int refsort_cmp(const void *a_void, const void *b_void)
2603 const struct refsort *a = a_void;
2604 const struct refsort *b = b_void;
2606 if (a->bytenr < b->bytenr)
2608 if (a->bytenr > b->bytenr)
2614 static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
2615 struct btrfs_root *root,
2616 struct extent_buffer *buf,
2617 int full_backref, int inc)
2624 struct btrfs_key key;
2625 struct btrfs_file_extent_item *fi;
2629 int (*process_func)(struct btrfs_trans_handle *, struct btrfs_root *,
2630 u64, u64, u64, u64, u64, u64);
2632 ref_root = btrfs_header_owner(buf);
2633 nritems = btrfs_header_nritems(buf);
2634 level = btrfs_header_level(buf);
2636 if (!root->ref_cows && level == 0)
2640 process_func = btrfs_inc_extent_ref;
2642 process_func = btrfs_free_extent;
2645 parent = buf->start;
2649 for (i = 0; i < nritems; i++) {
2651 btrfs_item_key_to_cpu(buf, &key, i);
2652 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2654 fi = btrfs_item_ptr(buf, i,
2655 struct btrfs_file_extent_item);
2656 if (btrfs_file_extent_type(buf, fi) ==
2657 BTRFS_FILE_EXTENT_INLINE)
2659 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2663 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
2664 key.offset -= btrfs_file_extent_offset(buf, fi);
2665 ret = process_func(trans, root, bytenr, num_bytes,
2666 parent, ref_root, key.objectid,
2671 bytenr = btrfs_node_blockptr(buf, i);
2672 num_bytes = btrfs_level_size(root, level - 1);
2673 ret = process_func(trans, root, bytenr, num_bytes,
2674 parent, ref_root, level - 1, 0);
2685 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2686 struct extent_buffer *buf, int full_backref)
2688 return __btrfs_mod_ref(trans, root, buf, full_backref, 1);
2691 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2692 struct extent_buffer *buf, int full_backref)
2694 return __btrfs_mod_ref(trans, root, buf, full_backref, 0);
2697 static int write_one_cache_group(struct btrfs_trans_handle *trans,
2698 struct btrfs_root *root,
2699 struct btrfs_path *path,
2700 struct btrfs_block_group_cache *cache)
2703 struct btrfs_root *extent_root = root->fs_info->extent_root;
2705 struct extent_buffer *leaf;
2707 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
2712 leaf = path->nodes[0];
2713 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
2714 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
2715 btrfs_mark_buffer_dirty(leaf);
2716 btrfs_release_path(extent_root, path);
2724 static struct btrfs_block_group_cache *
2725 next_block_group(struct btrfs_root *root,
2726 struct btrfs_block_group_cache *cache)
2728 struct rb_node *node;
2729 spin_lock(&root->fs_info->block_group_cache_lock);
2730 node = rb_next(&cache->cache_node);
2731 btrfs_put_block_group(cache);
2733 cache = rb_entry(node, struct btrfs_block_group_cache,
2735 btrfs_get_block_group(cache);
2738 spin_unlock(&root->fs_info->block_group_cache_lock);
2742 static int cache_save_setup(struct btrfs_block_group_cache *block_group,
2743 struct btrfs_trans_handle *trans,
2744 struct btrfs_path *path)
2746 struct btrfs_root *root = block_group->fs_info->tree_root;
2747 struct inode *inode = NULL;
2749 int dcs = BTRFS_DC_ERROR;
2755 * If this block group is smaller than 100 megs don't bother caching the
2758 if (block_group->key.offset < (100 * 1024 * 1024)) {
2759 spin_lock(&block_group->lock);
2760 block_group->disk_cache_state = BTRFS_DC_WRITTEN;
2761 spin_unlock(&block_group->lock);
2766 inode = lookup_free_space_inode(root, block_group, path);
2767 if (IS_ERR(inode) && PTR_ERR(inode) != -ENOENT) {
2768 ret = PTR_ERR(inode);
2769 btrfs_release_path(root, path);
2773 if (IS_ERR(inode)) {
2777 if (block_group->ro)
2780 ret = create_free_space_inode(root, trans, block_group, path);
2787 * We want to set the generation to 0, that way if anything goes wrong
2788 * from here on out we know not to trust this cache when we load up next
2791 BTRFS_I(inode)->generation = 0;
2792 ret = btrfs_update_inode(trans, root, inode);
2795 if (i_size_read(inode) > 0) {
2796 ret = btrfs_truncate_free_space_cache(root, trans, path,
2802 spin_lock(&block_group->lock);
2803 if (block_group->cached != BTRFS_CACHE_FINISHED) {
2804 /* We're not cached, don't bother trying to write stuff out */
2805 dcs = BTRFS_DC_WRITTEN;
2806 spin_unlock(&block_group->lock);
2809 spin_unlock(&block_group->lock);
2811 num_pages = (int)div64_u64(block_group->key.offset, 1024 * 1024 * 1024);
2816 * Just to make absolutely sure we have enough space, we're going to
2817 * preallocate 12 pages worth of space for each block group. In
2818 * practice we ought to use at most 8, but we need extra space so we can
2819 * add our header and have a terminator between the extents and the
2823 num_pages *= PAGE_CACHE_SIZE;
2825 ret = btrfs_check_data_free_space(inode, num_pages);
2829 ret = btrfs_prealloc_file_range_trans(inode, trans, 0, 0, num_pages,
2830 num_pages, num_pages,
2833 dcs = BTRFS_DC_SETUP;
2834 btrfs_free_reserved_data_space(inode, num_pages);
2838 btrfs_release_path(root, path);
2840 spin_lock(&block_group->lock);
2841 block_group->disk_cache_state = dcs;
2842 spin_unlock(&block_group->lock);
2847 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
2848 struct btrfs_root *root)
2850 struct btrfs_block_group_cache *cache;
2852 struct btrfs_path *path;
2855 path = btrfs_alloc_path();
2861 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2863 if (cache->disk_cache_state == BTRFS_DC_CLEAR)
2865 cache = next_block_group(root, cache);
2873 err = cache_save_setup(cache, trans, path);
2874 last = cache->key.objectid + cache->key.offset;
2875 btrfs_put_block_group(cache);
2880 err = btrfs_run_delayed_refs(trans, root,
2885 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2887 if (cache->disk_cache_state == BTRFS_DC_CLEAR) {
2888 btrfs_put_block_group(cache);
2894 cache = next_block_group(root, cache);
2903 if (cache->disk_cache_state == BTRFS_DC_SETUP)
2904 cache->disk_cache_state = BTRFS_DC_NEED_WRITE;
2906 last = cache->key.objectid + cache->key.offset;
2908 err = write_one_cache_group(trans, root, path, cache);
2910 btrfs_put_block_group(cache);
2915 * I don't think this is needed since we're just marking our
2916 * preallocated extent as written, but just in case it can't
2920 err = btrfs_run_delayed_refs(trans, root,
2925 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2928 * Really this shouldn't happen, but it could if we
2929 * couldn't write the entire preallocated extent and
2930 * splitting the extent resulted in a new block.
2933 btrfs_put_block_group(cache);
2936 if (cache->disk_cache_state == BTRFS_DC_NEED_WRITE)
2938 cache = next_block_group(root, cache);
2947 btrfs_write_out_cache(root, trans, cache, path);
2950 * If we didn't have an error then the cache state is still
2951 * NEED_WRITE, so we can set it to WRITTEN.
2953 if (cache->disk_cache_state == BTRFS_DC_NEED_WRITE)
2954 cache->disk_cache_state = BTRFS_DC_WRITTEN;
2955 last = cache->key.objectid + cache->key.offset;
2956 btrfs_put_block_group(cache);
2959 btrfs_free_path(path);
2963 int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr)
2965 struct btrfs_block_group_cache *block_group;
2968 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
2969 if (!block_group || block_group->ro)
2972 btrfs_put_block_group(block_group);
2976 static int update_space_info(struct btrfs_fs_info *info, u64 flags,
2977 u64 total_bytes, u64 bytes_used,
2978 struct btrfs_space_info **space_info)
2980 struct btrfs_space_info *found;
2984 if (flags & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
2985 BTRFS_BLOCK_GROUP_RAID10))
2990 found = __find_space_info(info, flags);
2992 spin_lock(&found->lock);
2993 found->total_bytes += total_bytes;
2994 found->disk_total += total_bytes * factor;
2995 found->bytes_used += bytes_used;
2996 found->disk_used += bytes_used * factor;
2998 spin_unlock(&found->lock);
2999 *space_info = found;
3002 found = kzalloc(sizeof(*found), GFP_NOFS);
3006 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
3007 INIT_LIST_HEAD(&found->block_groups[i]);
3008 init_rwsem(&found->groups_sem);
3009 spin_lock_init(&found->lock);
3010 found->flags = flags & (BTRFS_BLOCK_GROUP_DATA |
3011 BTRFS_BLOCK_GROUP_SYSTEM |
3012 BTRFS_BLOCK_GROUP_METADATA);
3013 found->total_bytes = total_bytes;
3014 found->disk_total = total_bytes * factor;
3015 found->bytes_used = bytes_used;
3016 found->disk_used = bytes_used * factor;
3017 found->bytes_pinned = 0;
3018 found->bytes_reserved = 0;
3019 found->bytes_readonly = 0;
3020 found->bytes_may_use = 0;
3022 found->force_alloc = 0;
3023 *space_info = found;
3024 list_add_rcu(&found->list, &info->space_info);
3025 atomic_set(&found->caching_threads, 0);
3029 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
3031 u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 |
3032 BTRFS_BLOCK_GROUP_RAID1 |
3033 BTRFS_BLOCK_GROUP_RAID10 |
3034 BTRFS_BLOCK_GROUP_DUP);
3036 if (flags & BTRFS_BLOCK_GROUP_DATA)
3037 fs_info->avail_data_alloc_bits |= extra_flags;
3038 if (flags & BTRFS_BLOCK_GROUP_METADATA)
3039 fs_info->avail_metadata_alloc_bits |= extra_flags;
3040 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
3041 fs_info->avail_system_alloc_bits |= extra_flags;
3045 u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
3048 * we add in the count of missing devices because we want
3049 * to make sure that any RAID levels on a degraded FS
3050 * continue to be honored.
3052 u64 num_devices = root->fs_info->fs_devices->rw_devices +
3053 root->fs_info->fs_devices->missing_devices;
3055 if (num_devices == 1)
3056 flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0);
3057 if (num_devices < 4)
3058 flags &= ~BTRFS_BLOCK_GROUP_RAID10;
3060 if ((flags & BTRFS_BLOCK_GROUP_DUP) &&
3061 (flags & (BTRFS_BLOCK_GROUP_RAID1 |
3062 BTRFS_BLOCK_GROUP_RAID10))) {
3063 flags &= ~BTRFS_BLOCK_GROUP_DUP;
3066 if ((flags & BTRFS_BLOCK_GROUP_RAID1) &&
3067 (flags & BTRFS_BLOCK_GROUP_RAID10)) {
3068 flags &= ~BTRFS_BLOCK_GROUP_RAID1;
3071 if ((flags & BTRFS_BLOCK_GROUP_RAID0) &&
3072 ((flags & BTRFS_BLOCK_GROUP_RAID1) |
3073 (flags & BTRFS_BLOCK_GROUP_RAID10) |
3074 (flags & BTRFS_BLOCK_GROUP_DUP)))
3075 flags &= ~BTRFS_BLOCK_GROUP_RAID0;
3079 static u64 get_alloc_profile(struct btrfs_root *root, u64 flags)
3081 if (flags & BTRFS_BLOCK_GROUP_DATA)
3082 flags |= root->fs_info->avail_data_alloc_bits &
3083 root->fs_info->data_alloc_profile;
3084 else if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
3085 flags |= root->fs_info->avail_system_alloc_bits &
3086 root->fs_info->system_alloc_profile;
3087 else if (flags & BTRFS_BLOCK_GROUP_METADATA)
3088 flags |= root->fs_info->avail_metadata_alloc_bits &
3089 root->fs_info->metadata_alloc_profile;
3090 return btrfs_reduce_alloc_profile(root, flags);
3093 u64 btrfs_get_alloc_profile(struct btrfs_root *root, int data)
3098 flags = BTRFS_BLOCK_GROUP_DATA;
3099 else if (root == root->fs_info->chunk_root)
3100 flags = BTRFS_BLOCK_GROUP_SYSTEM;
3102 flags = BTRFS_BLOCK_GROUP_METADATA;
3104 return get_alloc_profile(root, flags);
3107 void btrfs_set_inode_space_info(struct btrfs_root *root, struct inode *inode)
3109 BTRFS_I(inode)->space_info = __find_space_info(root->fs_info,
3110 BTRFS_BLOCK_GROUP_DATA);
3114 * This will check the space that the inode allocates from to make sure we have
3115 * enough space for bytes.
3117 int btrfs_check_data_free_space(struct inode *inode, u64 bytes)
3119 struct btrfs_space_info *data_sinfo;
3120 struct btrfs_root *root = BTRFS_I(inode)->root;
3122 int ret = 0, committed = 0, alloc_chunk = 1;
3124 /* make sure bytes are sectorsize aligned */
3125 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3127 if (root == root->fs_info->tree_root) {
3132 data_sinfo = BTRFS_I(inode)->space_info;
3137 /* make sure we have enough space to handle the data first */
3138 spin_lock(&data_sinfo->lock);
3139 used = data_sinfo->bytes_used + data_sinfo->bytes_reserved +
3140 data_sinfo->bytes_pinned + data_sinfo->bytes_readonly +
3141 data_sinfo->bytes_may_use;
3143 if (used + bytes > data_sinfo->total_bytes) {
3144 struct btrfs_trans_handle *trans;
3147 * if we don't have enough free bytes in this space then we need
3148 * to alloc a new chunk.
3150 if (!data_sinfo->full && alloc_chunk) {
3153 data_sinfo->force_alloc = 1;
3154 spin_unlock(&data_sinfo->lock);
3156 alloc_target = btrfs_get_alloc_profile(root, 1);
3157 trans = btrfs_join_transaction(root, 1);
3159 return PTR_ERR(trans);
3161 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
3162 bytes + 2 * 1024 * 1024,
3164 btrfs_end_transaction(trans, root);
3173 btrfs_set_inode_space_info(root, inode);
3174 data_sinfo = BTRFS_I(inode)->space_info;
3178 spin_unlock(&data_sinfo->lock);
3180 /* commit the current transaction and try again */
3182 if (!committed && !root->fs_info->open_ioctl_trans) {
3184 trans = btrfs_join_transaction(root, 1);
3186 return PTR_ERR(trans);
3187 ret = btrfs_commit_transaction(trans, root);
3193 #if 0 /* I hope we never need this code again, just in case */
3194 printk(KERN_ERR "no space left, need %llu, %llu bytes_used, "
3195 "%llu bytes_reserved, " "%llu bytes_pinned, "
3196 "%llu bytes_readonly, %llu may use %llu total\n",
3197 (unsigned long long)bytes,
3198 (unsigned long long)data_sinfo->bytes_used,
3199 (unsigned long long)data_sinfo->bytes_reserved,
3200 (unsigned long long)data_sinfo->bytes_pinned,
3201 (unsigned long long)data_sinfo->bytes_readonly,
3202 (unsigned long long)data_sinfo->bytes_may_use,
3203 (unsigned long long)data_sinfo->total_bytes);
3207 data_sinfo->bytes_may_use += bytes;
3208 BTRFS_I(inode)->reserved_bytes += bytes;
3209 spin_unlock(&data_sinfo->lock);
3215 * called when we are clearing an delalloc extent from the
3216 * inode's io_tree or there was an error for whatever reason
3217 * after calling btrfs_check_data_free_space
3219 void btrfs_free_reserved_data_space(struct inode *inode, u64 bytes)
3221 struct btrfs_root *root = BTRFS_I(inode)->root;
3222 struct btrfs_space_info *data_sinfo;
3224 /* make sure bytes are sectorsize aligned */
3225 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3227 data_sinfo = BTRFS_I(inode)->space_info;
3228 spin_lock(&data_sinfo->lock);
3229 data_sinfo->bytes_may_use -= bytes;
3230 BTRFS_I(inode)->reserved_bytes -= bytes;
3231 spin_unlock(&data_sinfo->lock);
3234 static void force_metadata_allocation(struct btrfs_fs_info *info)
3236 struct list_head *head = &info->space_info;
3237 struct btrfs_space_info *found;
3240 list_for_each_entry_rcu(found, head, list) {
3241 if (found->flags & BTRFS_BLOCK_GROUP_METADATA)
3242 found->force_alloc = 1;
3247 static int should_alloc_chunk(struct btrfs_root *root,
3248 struct btrfs_space_info *sinfo, u64 alloc_bytes)
3250 u64 num_bytes = sinfo->total_bytes - sinfo->bytes_readonly;
3253 if (sinfo->bytes_used + sinfo->bytes_reserved +
3254 alloc_bytes + 256 * 1024 * 1024 < num_bytes)
3257 if (sinfo->bytes_used + sinfo->bytes_reserved +
3258 alloc_bytes < div_factor(num_bytes, 8))
3261 thresh = btrfs_super_total_bytes(&root->fs_info->super_copy);
3262 thresh = max_t(u64, 256 * 1024 * 1024, div_factor_fine(thresh, 5));
3264 if (num_bytes > thresh && sinfo->bytes_used < div_factor(num_bytes, 3))
3270 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
3271 struct btrfs_root *extent_root, u64 alloc_bytes,
3272 u64 flags, int force)
3274 struct btrfs_space_info *space_info;
3275 struct btrfs_fs_info *fs_info = extent_root->fs_info;
3278 mutex_lock(&fs_info->chunk_mutex);
3280 flags = btrfs_reduce_alloc_profile(extent_root, flags);
3282 space_info = __find_space_info(extent_root->fs_info, flags);
3284 ret = update_space_info(extent_root->fs_info, flags,
3288 BUG_ON(!space_info);
3290 spin_lock(&space_info->lock);
3291 if (space_info->force_alloc)
3293 if (space_info->full) {
3294 spin_unlock(&space_info->lock);
3298 if (!force && !should_alloc_chunk(extent_root, space_info,
3300 spin_unlock(&space_info->lock);
3303 spin_unlock(&space_info->lock);
3306 * If we have mixed data/metadata chunks we want to make sure we keep
3307 * allocating mixed chunks instead of individual chunks.
3309 if (btrfs_mixed_space_info(space_info))
3310 flags |= (BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA);
3313 * if we're doing a data chunk, go ahead and make sure that
3314 * we keep a reasonable number of metadata chunks allocated in the
3317 if (flags & BTRFS_BLOCK_GROUP_DATA && fs_info->metadata_ratio) {
3318 fs_info->data_chunk_allocations++;
3319 if (!(fs_info->data_chunk_allocations %
3320 fs_info->metadata_ratio))
3321 force_metadata_allocation(fs_info);
3324 ret = btrfs_alloc_chunk(trans, extent_root, flags);
3325 spin_lock(&space_info->lock);
3327 space_info->full = 1;
3330 space_info->force_alloc = 0;
3331 spin_unlock(&space_info->lock);
3333 mutex_unlock(&extent_root->fs_info->chunk_mutex);
3338 * shrink metadata reservation for delalloc
3340 static int shrink_delalloc(struct btrfs_trans_handle *trans,
3341 struct btrfs_root *root, u64 to_reclaim, int sync)
3343 struct btrfs_block_rsv *block_rsv;
3344 struct btrfs_space_info *space_info;
3349 int nr_pages = (2 * 1024 * 1024) >> PAGE_CACHE_SHIFT;
3351 block_rsv = &root->fs_info->delalloc_block_rsv;
3352 space_info = block_rsv->space_info;
3355 reserved = space_info->bytes_reserved;
3360 max_reclaim = min(reserved, to_reclaim);
3363 /* have the flusher threads jump in and do some IO */
3365 nr_pages = min_t(unsigned long, nr_pages,
3366 root->fs_info->delalloc_bytes >> PAGE_CACHE_SHIFT);
3367 writeback_inodes_sb_nr_if_idle(root->fs_info->sb, nr_pages);
3369 spin_lock(&space_info->lock);
3370 if (reserved > space_info->bytes_reserved)
3371 reclaimed += reserved - space_info->bytes_reserved;
3372 reserved = space_info->bytes_reserved;
3373 spin_unlock(&space_info->lock);
3375 if (reserved == 0 || reclaimed >= max_reclaim)
3378 if (trans && trans->transaction->blocked)
3381 __set_current_state(TASK_INTERRUPTIBLE);
3382 schedule_timeout(pause);
3384 if (pause > HZ / 10)
3388 return reclaimed >= to_reclaim;
3392 * Retries tells us how many times we've called reserve_metadata_bytes. The
3393 * idea is if this is the first call (retries == 0) then we will add to our
3394 * reserved count if we can't make the allocation in order to hold our place
3395 * while we go and try and free up space. That way for retries > 1 we don't try
3396 * and add space, we just check to see if the amount of unused space is >= the
3397 * total space, meaning that our reservation is valid.
3399 * However if we don't intend to retry this reservation, pass -1 as retries so
3400 * that it short circuits this logic.
3402 static int reserve_metadata_bytes(struct btrfs_trans_handle *trans,
3403 struct btrfs_root *root,
3404 struct btrfs_block_rsv *block_rsv,
3405 u64 orig_bytes, int flush)
3407 struct btrfs_space_info *space_info = block_rsv->space_info;
3409 u64 num_bytes = orig_bytes;
3412 bool reserved = false;
3413 bool committed = false;
3420 spin_lock(&space_info->lock);
3421 unused = space_info->bytes_used + space_info->bytes_reserved +
3422 space_info->bytes_pinned + space_info->bytes_readonly +
3423 space_info->bytes_may_use;
3426 * The idea here is that we've not already over-reserved the block group
3427 * then we can go ahead and save our reservation first and then start
3428 * flushing if we need to. Otherwise if we've already overcommitted
3429 * lets start flushing stuff first and then come back and try to make
3432 if (unused <= space_info->total_bytes) {
3433 unused = space_info->total_bytes - unused;
3434 if (unused >= num_bytes) {
3436 space_info->bytes_reserved += orig_bytes;
3440 * Ok set num_bytes to orig_bytes since we aren't
3441 * overocmmitted, this way we only try and reclaim what
3444 num_bytes = orig_bytes;
3448 * Ok we're over committed, set num_bytes to the overcommitted
3449 * amount plus the amount of bytes that we need for this
3452 num_bytes = unused - space_info->total_bytes +
3453 (orig_bytes * (retries + 1));
3457 * Couldn't make our reservation, save our place so while we're trying
3458 * to reclaim space we can actually use it instead of somebody else
3459 * stealing it from us.
3461 if (ret && !reserved) {
3462 space_info->bytes_reserved += orig_bytes;
3466 spin_unlock(&space_info->lock);
3475 * We do synchronous shrinking since we don't actually unreserve
3476 * metadata until after the IO is completed.
3478 ret = shrink_delalloc(trans, root, num_bytes, 1);
3485 * So if we were overcommitted it's possible that somebody else flushed
3486 * out enough space and we simply didn't have enough space to reclaim,
3487 * so go back around and try again.
3494 spin_lock(&space_info->lock);
3496 * Not enough space to be reclaimed, don't bother committing the
3499 if (space_info->bytes_pinned < orig_bytes)
3501 spin_unlock(&space_info->lock);
3506 if (trans || committed)
3510 trans = btrfs_join_transaction(root, 1);
3513 ret = btrfs_commit_transaction(trans, root);
3522 spin_lock(&space_info->lock);
3523 space_info->bytes_reserved -= orig_bytes;
3524 spin_unlock(&space_info->lock);
3530 static struct btrfs_block_rsv *get_block_rsv(struct btrfs_trans_handle *trans,
3531 struct btrfs_root *root)
3533 struct btrfs_block_rsv *block_rsv;
3535 block_rsv = trans->block_rsv;
3537 block_rsv = root->block_rsv;
3540 block_rsv = &root->fs_info->empty_block_rsv;
3545 static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,
3549 spin_lock(&block_rsv->lock);
3550 if (block_rsv->reserved >= num_bytes) {
3551 block_rsv->reserved -= num_bytes;
3552 if (block_rsv->reserved < block_rsv->size)
3553 block_rsv->full = 0;
3556 spin_unlock(&block_rsv->lock);
3560 static void block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
3561 u64 num_bytes, int update_size)
3563 spin_lock(&block_rsv->lock);
3564 block_rsv->reserved += num_bytes;
3566 block_rsv->size += num_bytes;
3567 else if (block_rsv->reserved >= block_rsv->size)
3568 block_rsv->full = 1;
3569 spin_unlock(&block_rsv->lock);
3572 void block_rsv_release_bytes(struct btrfs_block_rsv *block_rsv,
3573 struct btrfs_block_rsv *dest, u64 num_bytes)
3575 struct btrfs_space_info *space_info = block_rsv->space_info;
3577 spin_lock(&block_rsv->lock);
3578 if (num_bytes == (u64)-1)
3579 num_bytes = block_rsv->size;
3580 block_rsv->size -= num_bytes;
3581 if (block_rsv->reserved >= block_rsv->size) {
3582 num_bytes = block_rsv->reserved - block_rsv->size;
3583 block_rsv->reserved = block_rsv->size;
3584 block_rsv->full = 1;
3588 spin_unlock(&block_rsv->lock);
3590 if (num_bytes > 0) {
3592 block_rsv_add_bytes(dest, num_bytes, 0);
3594 spin_lock(&space_info->lock);
3595 space_info->bytes_reserved -= num_bytes;
3596 spin_unlock(&space_info->lock);
3601 static int block_rsv_migrate_bytes(struct btrfs_block_rsv *src,
3602 struct btrfs_block_rsv *dst, u64 num_bytes)
3606 ret = block_rsv_use_bytes(src, num_bytes);
3610 block_rsv_add_bytes(dst, num_bytes, 1);
3614 void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv)
3616 memset(rsv, 0, sizeof(*rsv));
3617 spin_lock_init(&rsv->lock);
3618 atomic_set(&rsv->usage, 1);
3620 INIT_LIST_HEAD(&rsv->list);
3623 struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_root *root)
3625 struct btrfs_block_rsv *block_rsv;
3626 struct btrfs_fs_info *fs_info = root->fs_info;
3628 block_rsv = kmalloc(sizeof(*block_rsv), GFP_NOFS);
3632 btrfs_init_block_rsv(block_rsv);
3633 block_rsv->space_info = __find_space_info(fs_info,
3634 BTRFS_BLOCK_GROUP_METADATA);
3638 void btrfs_free_block_rsv(struct btrfs_root *root,
3639 struct btrfs_block_rsv *rsv)
3641 if (rsv && atomic_dec_and_test(&rsv->usage)) {
3642 btrfs_block_rsv_release(root, rsv, (u64)-1);
3649 * make the block_rsv struct be able to capture freed space.
3650 * the captured space will re-add to the the block_rsv struct
3651 * after transaction commit
3653 void btrfs_add_durable_block_rsv(struct btrfs_fs_info *fs_info,
3654 struct btrfs_block_rsv *block_rsv)
3656 block_rsv->durable = 1;
3657 mutex_lock(&fs_info->durable_block_rsv_mutex);
3658 list_add_tail(&block_rsv->list, &fs_info->durable_block_rsv_list);
3659 mutex_unlock(&fs_info->durable_block_rsv_mutex);
3662 int btrfs_block_rsv_add(struct btrfs_trans_handle *trans,
3663 struct btrfs_root *root,
3664 struct btrfs_block_rsv *block_rsv,
3672 ret = reserve_metadata_bytes(trans, root, block_rsv, num_bytes, 1);
3674 block_rsv_add_bytes(block_rsv, num_bytes, 1);
3681 int btrfs_block_rsv_check(struct btrfs_trans_handle *trans,
3682 struct btrfs_root *root,
3683 struct btrfs_block_rsv *block_rsv,
3684 u64 min_reserved, int min_factor)
3687 int commit_trans = 0;
3693 spin_lock(&block_rsv->lock);
3695 num_bytes = div_factor(block_rsv->size, min_factor);
3696 if (min_reserved > num_bytes)
3697 num_bytes = min_reserved;
3699 if (block_rsv->reserved >= num_bytes) {
3702 num_bytes -= block_rsv->reserved;
3703 if (block_rsv->durable &&
3704 block_rsv->freed[0] + block_rsv->freed[1] >= num_bytes)
3707 spin_unlock(&block_rsv->lock);
3711 if (block_rsv->refill_used) {
3712 ret = reserve_metadata_bytes(trans, root, block_rsv,
3715 block_rsv_add_bytes(block_rsv, num_bytes, 0);
3724 trans = btrfs_join_transaction(root, 1);
3725 BUG_ON(IS_ERR(trans));
3726 ret = btrfs_commit_transaction(trans, root);
3733 int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,
3734 struct btrfs_block_rsv *dst_rsv,
3737 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3740 void btrfs_block_rsv_release(struct btrfs_root *root,
3741 struct btrfs_block_rsv *block_rsv,
3744 struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
3745 if (global_rsv->full || global_rsv == block_rsv ||
3746 block_rsv->space_info != global_rsv->space_info)
3748 block_rsv_release_bytes(block_rsv, global_rsv, num_bytes);
3752 * helper to calculate size of global block reservation.
3753 * the desired value is sum of space used by extent tree,
3754 * checksum tree and root tree
3756 static u64 calc_global_metadata_size(struct btrfs_fs_info *fs_info)
3758 struct btrfs_space_info *sinfo;
3762 int csum_size = btrfs_super_csum_size(&fs_info->super_copy);
3765 * per tree used space accounting can be inaccuracy, so we
3768 spin_lock(&fs_info->extent_root->accounting_lock);
3769 num_bytes = btrfs_root_used(&fs_info->extent_root->root_item);
3770 spin_unlock(&fs_info->extent_root->accounting_lock);
3772 spin_lock(&fs_info->csum_root->accounting_lock);
3773 num_bytes += btrfs_root_used(&fs_info->csum_root->root_item);
3774 spin_unlock(&fs_info->csum_root->accounting_lock);
3776 spin_lock(&fs_info->tree_root->accounting_lock);
3777 num_bytes += btrfs_root_used(&fs_info->tree_root->root_item);
3778 spin_unlock(&fs_info->tree_root->accounting_lock);
3780 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_DATA);
3781 spin_lock(&sinfo->lock);
3782 data_used = sinfo->bytes_used;
3783 spin_unlock(&sinfo->lock);
3785 sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
3786 spin_lock(&sinfo->lock);
3787 if (sinfo->flags & BTRFS_BLOCK_GROUP_DATA)
3789 meta_used = sinfo->bytes_used;
3790 spin_unlock(&sinfo->lock);
3792 num_bytes = (data_used >> fs_info->sb->s_blocksize_bits) *
3794 num_bytes += div64_u64(data_used + meta_used, 50);
3796 if (num_bytes * 3 > meta_used)
3797 num_bytes = div64_u64(meta_used, 3);
3799 return ALIGN(num_bytes, fs_info->extent_root->leafsize << 10);
3802 static void update_global_block_rsv(struct btrfs_fs_info *fs_info)
3804 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
3805 struct btrfs_space_info *sinfo = block_rsv->space_info;
3808 num_bytes = calc_global_metadata_size(fs_info);
3810 spin_lock(&block_rsv->lock);
3811 spin_lock(&sinfo->lock);
3813 block_rsv->size = num_bytes;
3815 num_bytes = sinfo->bytes_used + sinfo->bytes_pinned +
3816 sinfo->bytes_reserved + sinfo->bytes_readonly +
3817 sinfo->bytes_may_use;
3819 if (sinfo->total_bytes > num_bytes) {
3820 num_bytes = sinfo->total_bytes - num_bytes;
3821 block_rsv->reserved += num_bytes;
3822 sinfo->bytes_reserved += num_bytes;
3825 if (block_rsv->reserved >= block_rsv->size) {
3826 num_bytes = block_rsv->reserved - block_rsv->size;
3827 sinfo->bytes_reserved -= num_bytes;
3828 block_rsv->reserved = block_rsv->size;
3829 block_rsv->full = 1;
3832 printk(KERN_INFO"global block rsv size %llu reserved %llu\n",
3833 block_rsv->size, block_rsv->reserved);
3835 spin_unlock(&sinfo->lock);
3836 spin_unlock(&block_rsv->lock);
3839 static void init_global_block_rsv(struct btrfs_fs_info *fs_info)
3841 struct btrfs_space_info *space_info;
3843 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
3844 fs_info->chunk_block_rsv.space_info = space_info;
3845 fs_info->chunk_block_rsv.priority = 10;
3847 space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
3848 fs_info->global_block_rsv.space_info = space_info;
3849 fs_info->global_block_rsv.priority = 10;
3850 fs_info->global_block_rsv.refill_used = 1;
3851 fs_info->delalloc_block_rsv.space_info = space_info;
3852 fs_info->trans_block_rsv.space_info = space_info;
3853 fs_info->empty_block_rsv.space_info = space_info;
3854 fs_info->empty_block_rsv.priority = 10;
3856 fs_info->extent_root->block_rsv = &fs_info->global_block_rsv;
3857 fs_info->csum_root->block_rsv = &fs_info->global_block_rsv;
3858 fs_info->dev_root->block_rsv = &fs_info->global_block_rsv;
3859 fs_info->tree_root->block_rsv = &fs_info->global_block_rsv;
3860 fs_info->chunk_root->block_rsv = &fs_info->chunk_block_rsv;
3862 btrfs_add_durable_block_rsv(fs_info, &fs_info->global_block_rsv);
3864 btrfs_add_durable_block_rsv(fs_info, &fs_info->delalloc_block_rsv);
3866 update_global_block_rsv(fs_info);
3869 static void release_global_block_rsv(struct btrfs_fs_info *fs_info)
3871 block_rsv_release_bytes(&fs_info->global_block_rsv, NULL, (u64)-1);
3872 WARN_ON(fs_info->delalloc_block_rsv.size > 0);
3873 WARN_ON(fs_info->delalloc_block_rsv.reserved > 0);
3874 WARN_ON(fs_info->trans_block_rsv.size > 0);
3875 WARN_ON(fs_info->trans_block_rsv.reserved > 0);
3876 WARN_ON(fs_info->chunk_block_rsv.size > 0);
3877 WARN_ON(fs_info->chunk_block_rsv.reserved > 0);
3880 static u64 calc_trans_metadata_size(struct btrfs_root *root, int num_items)
3882 return (root->leafsize + root->nodesize * (BTRFS_MAX_LEVEL - 1)) *
3886 int btrfs_trans_reserve_metadata(struct btrfs_trans_handle *trans,
3887 struct btrfs_root *root,
3893 if (num_items == 0 || root->fs_info->chunk_root == root)
3896 num_bytes = calc_trans_metadata_size(root, num_items);
3897 ret = btrfs_block_rsv_add(trans, root, &root->fs_info->trans_block_rsv,
3900 trans->bytes_reserved += num_bytes;
3901 trans->block_rsv = &root->fs_info->trans_block_rsv;
3906 void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans,
3907 struct btrfs_root *root)
3909 if (!trans->bytes_reserved)
3912 BUG_ON(trans->block_rsv != &root->fs_info->trans_block_rsv);
3913 btrfs_block_rsv_release(root, trans->block_rsv,
3914 trans->bytes_reserved);
3915 trans->bytes_reserved = 0;
3918 int btrfs_orphan_reserve_metadata(struct btrfs_trans_handle *trans,
3919 struct inode *inode)
3921 struct btrfs_root *root = BTRFS_I(inode)->root;
3922 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
3923 struct btrfs_block_rsv *dst_rsv = root->orphan_block_rsv;
3926 * one for deleting orphan item, one for updating inode and
3927 * two for calling btrfs_truncate_inode_items.
3929 * btrfs_truncate_inode_items is a delete operation, it frees
3930 * more space than it uses in most cases. So two units of
3931 * metadata space should be enough for calling it many times.
3932 * If all of the metadata space is used, we can commit
3933 * transaction and use space it freed.
3935 u64 num_bytes = calc_trans_metadata_size(root, 4);
3936 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3939 void btrfs_orphan_release_metadata(struct inode *inode)
3941 struct btrfs_root *root = BTRFS_I(inode)->root;
3942 u64 num_bytes = calc_trans_metadata_size(root, 4);
3943 btrfs_block_rsv_release(root, root->orphan_block_rsv, num_bytes);
3946 int btrfs_snap_reserve_metadata(struct btrfs_trans_handle *trans,
3947 struct btrfs_pending_snapshot *pending)
3949 struct btrfs_root *root = pending->root;
3950 struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
3951 struct btrfs_block_rsv *dst_rsv = &pending->block_rsv;
3953 * two for root back/forward refs, two for directory entries
3954 * and one for root of the snapshot.
3956 u64 num_bytes = calc_trans_metadata_size(root, 5);
3957 dst_rsv->space_info = src_rsv->space_info;
3958 return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
3961 static u64 calc_csum_metadata_size(struct inode *inode, u64 num_bytes)
3963 return num_bytes >>= 3;
3966 int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
3968 struct btrfs_root *root = BTRFS_I(inode)->root;
3969 struct btrfs_block_rsv *block_rsv = &root->fs_info->delalloc_block_rsv;
3974 if (btrfs_transaction_in_commit(root->fs_info))
3975 schedule_timeout(1);
3977 num_bytes = ALIGN(num_bytes, root->sectorsize);
3979 spin_lock(&BTRFS_I(inode)->accounting_lock);
3980 nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents) + 1;
3981 if (nr_extents > BTRFS_I(inode)->reserved_extents) {
3982 nr_extents -= BTRFS_I(inode)->reserved_extents;
3983 to_reserve = calc_trans_metadata_size(root, nr_extents);
3988 spin_unlock(&BTRFS_I(inode)->accounting_lock);
3990 to_reserve += calc_csum_metadata_size(inode, num_bytes);
3991 ret = reserve_metadata_bytes(NULL, root, block_rsv, to_reserve, 1);
3995 spin_lock(&BTRFS_I(inode)->accounting_lock);
3996 BTRFS_I(inode)->reserved_extents += nr_extents;
3997 atomic_inc(&BTRFS_I(inode)->outstanding_extents);
3998 spin_unlock(&BTRFS_I(inode)->accounting_lock);
4000 block_rsv_add_bytes(block_rsv, to_reserve, 1);
4002 if (block_rsv->size > 512 * 1024 * 1024)
4003 shrink_delalloc(NULL, root, to_reserve, 0);
4008 void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes)
4010 struct btrfs_root *root = BTRFS_I(inode)->root;
4014 num_bytes = ALIGN(num_bytes, root->sectorsize);
4015 atomic_dec(&BTRFS_I(inode)->outstanding_extents);
4017 spin_lock(&BTRFS_I(inode)->accounting_lock);
4018 nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents);
4019 if (nr_extents < BTRFS_I(inode)->reserved_extents) {
4020 nr_extents = BTRFS_I(inode)->reserved_extents - nr_extents;
4021 BTRFS_I(inode)->reserved_extents -= nr_extents;
4025 spin_unlock(&BTRFS_I(inode)->accounting_lock);
4027 to_free = calc_csum_metadata_size(inode, num_bytes);
4029 to_free += calc_trans_metadata_size(root, nr_extents);
4031 btrfs_block_rsv_release(root, &root->fs_info->delalloc_block_rsv,
4035 int btrfs_delalloc_reserve_space(struct inode *inode, u64 num_bytes)
4039 ret = btrfs_check_data_free_space(inode, num_bytes);
4043 ret = btrfs_delalloc_reserve_metadata(inode, num_bytes);
4045 btrfs_free_reserved_data_space(inode, num_bytes);
4052 void btrfs_delalloc_release_space(struct inode *inode, u64 num_bytes)
4054 btrfs_delalloc_release_metadata(inode, num_bytes);
4055 btrfs_free_reserved_data_space(inode, num_bytes);
4058 static int update_block_group(struct btrfs_trans_handle *trans,
4059 struct btrfs_root *root,
4060 u64 bytenr, u64 num_bytes, int alloc)
4062 struct btrfs_block_group_cache *cache = NULL;
4063 struct btrfs_fs_info *info = root->fs_info;
4064 u64 total = num_bytes;
4069 /* block accounting for super block */
4070 spin_lock(&info->delalloc_lock);
4071 old_val = btrfs_super_bytes_used(&info->super_copy);
4073 old_val += num_bytes;
4075 old_val -= num_bytes;
4076 btrfs_set_super_bytes_used(&info->super_copy, old_val);
4077 spin_unlock(&info->delalloc_lock);
4080 cache = btrfs_lookup_block_group(info, bytenr);
4083 if (cache->flags & (BTRFS_BLOCK_GROUP_DUP |
4084 BTRFS_BLOCK_GROUP_RAID1 |
4085 BTRFS_BLOCK_GROUP_RAID10))
4090 * If this block group has free space cache written out, we
4091 * need to make sure to load it if we are removing space. This
4092 * is because we need the unpinning stage to actually add the
4093 * space back to the block group, otherwise we will leak space.
4095 if (!alloc && cache->cached == BTRFS_CACHE_NO)
4096 cache_block_group(cache, trans, NULL, 1);
4098 byte_in_group = bytenr - cache->key.objectid;
4099 WARN_ON(byte_in_group > cache->key.offset);
4101 spin_lock(&cache->space_info->lock);
4102 spin_lock(&cache->lock);
4104 if (btrfs_super_cache_generation(&info->super_copy) != 0 &&
4105 cache->disk_cache_state < BTRFS_DC_CLEAR)
4106 cache->disk_cache_state = BTRFS_DC_CLEAR;
4109 old_val = btrfs_block_group_used(&cache->item);
4110 num_bytes = min(total, cache->key.offset - byte_in_group);
4112 old_val += num_bytes;
4113 btrfs_set_block_group_used(&cache->item, old_val);
4114 cache->reserved -= num_bytes;
4115 cache->space_info->bytes_reserved -= num_bytes;
4116 cache->space_info->bytes_used += num_bytes;
4117 cache->space_info->disk_used += num_bytes * factor;
4118 spin_unlock(&cache->lock);
4119 spin_unlock(&cache->space_info->lock);
4121 old_val -= num_bytes;
4122 btrfs_set_block_group_used(&cache->item, old_val);
4123 cache->pinned += num_bytes;
4124 cache->space_info->bytes_pinned += num_bytes;
4125 cache->space_info->bytes_used -= num_bytes;
4126 cache->space_info->disk_used -= num_bytes * factor;
4127 spin_unlock(&cache->lock);
4128 spin_unlock(&cache->space_info->lock);
4130 set_extent_dirty(info->pinned_extents,
4131 bytenr, bytenr + num_bytes - 1,
4132 GFP_NOFS | __GFP_NOFAIL);
4134 btrfs_put_block_group(cache);
4136 bytenr += num_bytes;
4141 static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
4143 struct btrfs_block_group_cache *cache;
4146 cache = btrfs_lookup_first_block_group(root->fs_info, search_start);
4150 bytenr = cache->key.objectid;
4151 btrfs_put_block_group(cache);
4156 static int pin_down_extent(struct btrfs_root *root,
4157 struct btrfs_block_group_cache *cache,
4158 u64 bytenr, u64 num_bytes, int reserved)
4160 spin_lock(&cache->space_info->lock);
4161 spin_lock(&cache->lock);
4162 cache->pinned += num_bytes;
4163 cache->space_info->bytes_pinned += num_bytes;
4165 cache->reserved -= num_bytes;
4166 cache->space_info->bytes_reserved -= num_bytes;
4168 spin_unlock(&cache->lock);
4169 spin_unlock(&cache->space_info->lock);
4171 set_extent_dirty(root->fs_info->pinned_extents, bytenr,
4172 bytenr + num_bytes - 1, GFP_NOFS | __GFP_NOFAIL);
4177 * this function must be called within transaction
4179 int btrfs_pin_extent(struct btrfs_root *root,
4180 u64 bytenr, u64 num_bytes, int reserved)
4182 struct btrfs_block_group_cache *cache;
4184 cache = btrfs_lookup_block_group(root->fs_info, bytenr);
4187 pin_down_extent(root, cache, bytenr, num_bytes, reserved);
4189 btrfs_put_block_group(cache);
4194 * update size of reserved extents. this function may return -EAGAIN
4195 * if 'reserve' is true or 'sinfo' is false.
4197 static int update_reserved_bytes(struct btrfs_block_group_cache *cache,
4198 u64 num_bytes, int reserve, int sinfo)
4202 struct btrfs_space_info *space_info = cache->space_info;
4203 spin_lock(&space_info->lock);
4204 spin_lock(&cache->lock);
4209 cache->reserved += num_bytes;
4210 space_info->bytes_reserved += num_bytes;
4214 space_info->bytes_readonly += num_bytes;
4215 cache->reserved -= num_bytes;
4216 space_info->bytes_reserved -= num_bytes;
4218 spin_unlock(&cache->lock);
4219 spin_unlock(&space_info->lock);
4221 spin_lock(&cache->lock);
4226 cache->reserved += num_bytes;
4228 cache->reserved -= num_bytes;
4230 spin_unlock(&cache->lock);
4235 int btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
4236 struct btrfs_root *root)
4238 struct btrfs_fs_info *fs_info = root->fs_info;
4239 struct btrfs_caching_control *next;
4240 struct btrfs_caching_control *caching_ctl;
4241 struct btrfs_block_group_cache *cache;
4243 down_write(&fs_info->extent_commit_sem);
4245 list_for_each_entry_safe(caching_ctl, next,
4246 &fs_info->caching_block_groups, list) {
4247 cache = caching_ctl->block_group;
4248 if (block_group_cache_done(cache)) {
4249 cache->last_byte_to_unpin = (u64)-1;
4250 list_del_init(&caching_ctl->list);
4251 put_caching_control(caching_ctl);
4253 cache->last_byte_to_unpin = caching_ctl->progress;
4257 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
4258 fs_info->pinned_extents = &fs_info->freed_extents[1];
4260 fs_info->pinned_extents = &fs_info->freed_extents[0];
4262 up_write(&fs_info->extent_commit_sem);
4264 update_global_block_rsv(fs_info);
4268 static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
4270 struct btrfs_fs_info *fs_info = root->fs_info;
4271 struct btrfs_block_group_cache *cache = NULL;
4274 while (start <= end) {
4276 start >= cache->key.objectid + cache->key.offset) {
4278 btrfs_put_block_group(cache);
4279 cache = btrfs_lookup_block_group(fs_info, start);
4283 len = cache->key.objectid + cache->key.offset - start;
4284 len = min(len, end + 1 - start);
4286 if (start < cache->last_byte_to_unpin) {
4287 len = min(len, cache->last_byte_to_unpin - start);
4288 btrfs_add_free_space(cache, start, len);
4293 spin_lock(&cache->space_info->lock);
4294 spin_lock(&cache->lock);
4295 cache->pinned -= len;
4296 cache->space_info->bytes_pinned -= len;
4298 cache->space_info->bytes_readonly += len;
4299 } else if (cache->reserved_pinned > 0) {
4300 len = min(len, cache->reserved_pinned);
4301 cache->reserved_pinned -= len;
4302 cache->space_info->bytes_reserved += len;
4304 spin_unlock(&cache->lock);
4305 spin_unlock(&cache->space_info->lock);
4309 btrfs_put_block_group(cache);
4313 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
4314 struct btrfs_root *root)
4316 struct btrfs_fs_info *fs_info = root->fs_info;
4317 struct extent_io_tree *unpin;
4318 struct btrfs_block_rsv *block_rsv;
4319 struct btrfs_block_rsv *next_rsv;
4325 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
4326 unpin = &fs_info->freed_extents[1];
4328 unpin = &fs_info->freed_extents[0];
4331 ret = find_first_extent_bit(unpin, 0, &start, &end,
4336 ret = btrfs_discard_extent(root, start, end + 1 - start);
4338 clear_extent_dirty(unpin, start, end, GFP_NOFS);
4339 unpin_extent_range(root, start, end);
4343 mutex_lock(&fs_info->durable_block_rsv_mutex);
4344 list_for_each_entry_safe(block_rsv, next_rsv,
4345 &fs_info->durable_block_rsv_list, list) {
4347 idx = trans->transid & 0x1;
4348 if (block_rsv->freed[idx] > 0) {
4349 block_rsv_add_bytes(block_rsv,
4350 block_rsv->freed[idx], 0);
4351 block_rsv->freed[idx] = 0;
4353 if (atomic_read(&block_rsv->usage) == 0) {
4354 btrfs_block_rsv_release(root, block_rsv, (u64)-1);
4356 if (block_rsv->freed[0] == 0 &&
4357 block_rsv->freed[1] == 0) {
4358 list_del_init(&block_rsv->list);
4362 btrfs_block_rsv_release(root, block_rsv, 0);
4365 mutex_unlock(&fs_info->durable_block_rsv_mutex);
4370 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
4371 struct btrfs_root *root,
4372 u64 bytenr, u64 num_bytes, u64 parent,
4373 u64 root_objectid, u64 owner_objectid,
4374 u64 owner_offset, int refs_to_drop,
4375 struct btrfs_delayed_extent_op *extent_op)
4377 struct btrfs_key key;
4378 struct btrfs_path *path;
4379 struct btrfs_fs_info *info = root->fs_info;
4380 struct btrfs_root *extent_root = info->extent_root;
4381 struct extent_buffer *leaf;
4382 struct btrfs_extent_item *ei;
4383 struct btrfs_extent_inline_ref *iref;
4386 int extent_slot = 0;
4387 int found_extent = 0;
4392 path = btrfs_alloc_path();
4397 path->leave_spinning = 1;
4399 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
4400 BUG_ON(!is_data && refs_to_drop != 1);
4402 ret = lookup_extent_backref(trans, extent_root, path, &iref,
4403 bytenr, num_bytes, parent,
4404 root_objectid, owner_objectid,
4407 extent_slot = path->slots[0];
4408 while (extent_slot >= 0) {
4409 btrfs_item_key_to_cpu(path->nodes[0], &key,
4411 if (key.objectid != bytenr)
4413 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
4414 key.offset == num_bytes) {
4418 if (path->slots[0] - extent_slot > 5)
4422 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
4423 item_size = btrfs_item_size_nr(path->nodes[0], extent_slot);
4424 if (found_extent && item_size < sizeof(*ei))
4427 if (!found_extent) {
4429 ret = remove_extent_backref(trans, extent_root, path,
4433 btrfs_release_path(extent_root, path);
4434 path->leave_spinning = 1;
4436 key.objectid = bytenr;
4437 key.type = BTRFS_EXTENT_ITEM_KEY;
4438 key.offset = num_bytes;
4440 ret = btrfs_search_slot(trans, extent_root,
4443 printk(KERN_ERR "umm, got %d back from search"
4444 ", was looking for %llu\n", ret,
4445 (unsigned long long)bytenr);
4446 btrfs_print_leaf(extent_root, path->nodes[0]);
4449 extent_slot = path->slots[0];
4452 btrfs_print_leaf(extent_root, path->nodes[0]);
4454 printk(KERN_ERR "btrfs unable to find ref byte nr %llu "
4455 "parent %llu root %llu owner %llu offset %llu\n",
4456 (unsigned long long)bytenr,
4457 (unsigned long long)parent,
4458 (unsigned long long)root_objectid,
4459 (unsigned long long)owner_objectid,
4460 (unsigned long long)owner_offset);
4463 leaf = path->nodes[0];
4464 item_size = btrfs_item_size_nr(leaf, extent_slot);
4465 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
4466 if (item_size < sizeof(*ei)) {
4467 BUG_ON(found_extent || extent_slot != path->slots[0]);
4468 ret = convert_extent_item_v0(trans, extent_root, path,
4472 btrfs_release_path(extent_root, path);
4473 path->leave_spinning = 1;
4475 key.objectid = bytenr;
4476 key.type = BTRFS_EXTENT_ITEM_KEY;
4477 key.offset = num_bytes;
4479 ret = btrfs_search_slot(trans, extent_root, &key, path,
4482 printk(KERN_ERR "umm, got %d back from search"
4483 ", was looking for %llu\n", ret,
4484 (unsigned long long)bytenr);
4485 btrfs_print_leaf(extent_root, path->nodes[0]);
4488 extent_slot = path->slots[0];
4489 leaf = path->nodes[0];
4490 item_size = btrfs_item_size_nr(leaf, extent_slot);
4493 BUG_ON(item_size < sizeof(*ei));
4494 ei = btrfs_item_ptr(leaf, extent_slot,
4495 struct btrfs_extent_item);
4496 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID) {
4497 struct btrfs_tree_block_info *bi;
4498 BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
4499 bi = (struct btrfs_tree_block_info *)(ei + 1);
4500 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
4503 refs = btrfs_extent_refs(leaf, ei);
4504 BUG_ON(refs < refs_to_drop);
4505 refs -= refs_to_drop;
4509 __run_delayed_extent_op(extent_op, leaf, ei);
4511 * In the case of inline back ref, reference count will
4512 * be updated by remove_extent_backref
4515 BUG_ON(!found_extent);
4517 btrfs_set_extent_refs(leaf, ei, refs);
4518 btrfs_mark_buffer_dirty(leaf);
4521 ret = remove_extent_backref(trans, extent_root, path,
4528 BUG_ON(is_data && refs_to_drop !=
4529 extent_data_ref_count(root, path, iref));
4531 BUG_ON(path->slots[0] != extent_slot);
4533 BUG_ON(path->slots[0] != extent_slot + 1);
4534 path->slots[0] = extent_slot;
4539 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
4542 btrfs_release_path(extent_root, path);
4545 ret = btrfs_del_csums(trans, root, bytenr, num_bytes);
4548 invalidate_mapping_pages(info->btree_inode->i_mapping,
4549 bytenr >> PAGE_CACHE_SHIFT,
4550 (bytenr + num_bytes - 1) >> PAGE_CACHE_SHIFT);
4553 ret = update_block_group(trans, root, bytenr, num_bytes, 0);
4556 btrfs_free_path(path);
4561 * when we free an block, it is possible (and likely) that we free the last
4562 * delayed ref for that extent as well. This searches the delayed ref tree for
4563 * a given extent, and if there are no other delayed refs to be processed, it
4564 * removes it from the tree.
4566 static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans,
4567 struct btrfs_root *root, u64 bytenr)
4569 struct btrfs_delayed_ref_head *head;
4570 struct btrfs_delayed_ref_root *delayed_refs;
4571 struct btrfs_delayed_ref_node *ref;
4572 struct rb_node *node;
4575 delayed_refs = &trans->transaction->delayed_refs;
4576 spin_lock(&delayed_refs->lock);
4577 head = btrfs_find_delayed_ref_head(trans, bytenr);
4581 node = rb_prev(&head->node.rb_node);
4585 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
4587 /* there are still entries for this ref, we can't drop it */
4588 if (ref->bytenr == bytenr)
4591 if (head->extent_op) {
4592 if (!head->must_insert_reserved)
4594 kfree(head->extent_op);
4595 head->extent_op = NULL;
4599 * waiting for the lock here would deadlock. If someone else has it
4600 * locked they are already in the process of dropping it anyway
4602 if (!mutex_trylock(&head->mutex))
4606 * at this point we have a head with no other entries. Go
4607 * ahead and process it.
4609 head->node.in_tree = 0;
4610 rb_erase(&head->node.rb_node, &delayed_refs->root);
4612 delayed_refs->num_entries--;
4615 * we don't take a ref on the node because we're removing it from the
4616 * tree, so we just steal the ref the tree was holding.
4618 delayed_refs->num_heads--;
4619 if (list_empty(&head->cluster))
4620 delayed_refs->num_heads_ready--;
4622 list_del_init(&head->cluster);
4623 spin_unlock(&delayed_refs->lock);
4625 BUG_ON(head->extent_op);
4626 if (head->must_insert_reserved)
4629 mutex_unlock(&head->mutex);
4630 btrfs_put_delayed_ref(&head->node);
4633 spin_unlock(&delayed_refs->lock);
4637 void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
4638 struct btrfs_root *root,
4639 struct extent_buffer *buf,
4640 u64 parent, int last_ref)
4642 struct btrfs_block_rsv *block_rsv;
4643 struct btrfs_block_group_cache *cache = NULL;
4646 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4647 ret = btrfs_add_delayed_tree_ref(trans, buf->start, buf->len,
4648 parent, root->root_key.objectid,
4649 btrfs_header_level(buf),
4650 BTRFS_DROP_DELAYED_REF, NULL);
4657 block_rsv = get_block_rsv(trans, root);
4658 cache = btrfs_lookup_block_group(root->fs_info, buf->start);
4659 if (block_rsv->space_info != cache->space_info)
4662 if (btrfs_header_generation(buf) == trans->transid) {
4663 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4664 ret = check_ref_cleanup(trans, root, buf->start);
4669 if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
4670 pin_down_extent(root, cache, buf->start, buf->len, 1);
4674 WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags));
4676 btrfs_add_free_space(cache, buf->start, buf->len);
4677 ret = update_reserved_bytes(cache, buf->len, 0, 0);
4678 if (ret == -EAGAIN) {
4679 /* block group became read-only */
4680 update_reserved_bytes(cache, buf->len, 0, 1);
4685 spin_lock(&block_rsv->lock);
4686 if (block_rsv->reserved < block_rsv->size) {
4687 block_rsv->reserved += buf->len;
4690 spin_unlock(&block_rsv->lock);
4693 spin_lock(&cache->space_info->lock);
4694 cache->space_info->bytes_reserved -= buf->len;
4695 spin_unlock(&cache->space_info->lock);
4700 if (block_rsv->durable && !cache->ro) {
4702 spin_lock(&cache->lock);
4704 cache->reserved_pinned += buf->len;
4707 spin_unlock(&cache->lock);
4710 spin_lock(&block_rsv->lock);
4711 block_rsv->freed[trans->transid & 0x1] += buf->len;
4712 spin_unlock(&block_rsv->lock);
4716 btrfs_put_block_group(cache);
4719 int btrfs_free_extent(struct btrfs_trans_handle *trans,
4720 struct btrfs_root *root,
4721 u64 bytenr, u64 num_bytes, u64 parent,
4722 u64 root_objectid, u64 owner, u64 offset)
4727 * tree log blocks never actually go into the extent allocation
4728 * tree, just update pinning info and exit early.
4730 if (root_objectid == BTRFS_TREE_LOG_OBJECTID) {
4731 WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID);
4732 /* unlocks the pinned mutex */
4733 btrfs_pin_extent(root, bytenr, num_bytes, 1);
4735 } else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
4736 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
4737 parent, root_objectid, (int)owner,
4738 BTRFS_DROP_DELAYED_REF, NULL);
4741 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
4742 parent, root_objectid, owner,
4743 offset, BTRFS_DROP_DELAYED_REF, NULL);
4749 static u64 stripe_align(struct btrfs_root *root, u64 val)
4751 u64 mask = ((u64)root->stripesize - 1);
4752 u64 ret = (val + mask) & ~mask;
4757 * when we wait for progress in the block group caching, its because
4758 * our allocation attempt failed at least once. So, we must sleep
4759 * and let some progress happen before we try again.
4761 * This function will sleep at least once waiting for new free space to
4762 * show up, and then it will check the block group free space numbers
4763 * for our min num_bytes. Another option is to have it go ahead
4764 * and look in the rbtree for a free extent of a given size, but this
4768 wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
4771 struct btrfs_caching_control *caching_ctl;
4774 caching_ctl = get_caching_control(cache);
4778 wait_event(caching_ctl->wait, block_group_cache_done(cache) ||
4779 (cache->free_space >= num_bytes));
4781 put_caching_control(caching_ctl);
4786 wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
4788 struct btrfs_caching_control *caching_ctl;
4791 caching_ctl = get_caching_control(cache);
4795 wait_event(caching_ctl->wait, block_group_cache_done(cache));
4797 put_caching_control(caching_ctl);
4801 static int get_block_group_index(struct btrfs_block_group_cache *cache)
4804 if (cache->flags & BTRFS_BLOCK_GROUP_RAID10)
4806 else if (cache->flags & BTRFS_BLOCK_GROUP_RAID1)
4808 else if (cache->flags & BTRFS_BLOCK_GROUP_DUP)
4810 else if (cache->flags & BTRFS_BLOCK_GROUP_RAID0)
4817 enum btrfs_loop_type {
4818 LOOP_FIND_IDEAL = 0,
4819 LOOP_CACHING_NOWAIT = 1,
4820 LOOP_CACHING_WAIT = 2,
4821 LOOP_ALLOC_CHUNK = 3,
4822 LOOP_NO_EMPTY_SIZE = 4,
4826 * walks the btree of allocated extents and find a hole of a given size.
4827 * The key ins is changed to record the hole:
4828 * ins->objectid == block start
4829 * ins->flags = BTRFS_EXTENT_ITEM_KEY
4830 * ins->offset == number of blocks
4831 * Any available blocks before search_start are skipped.
4833 static noinline int find_free_extent(struct btrfs_trans_handle *trans,
4834 struct btrfs_root *orig_root,
4835 u64 num_bytes, u64 empty_size,
4836 u64 search_start, u64 search_end,
4837 u64 hint_byte, struct btrfs_key *ins,
4841 struct btrfs_root *root = orig_root->fs_info->extent_root;
4842 struct btrfs_free_cluster *last_ptr = NULL;
4843 struct btrfs_block_group_cache *block_group = NULL;
4844 int empty_cluster = 2 * 1024 * 1024;
4845 int allowed_chunk_alloc = 0;
4846 int done_chunk_alloc = 0;
4847 struct btrfs_space_info *space_info;
4848 int last_ptr_loop = 0;
4851 bool found_uncached_bg = false;
4852 bool failed_cluster_refill = false;
4853 bool failed_alloc = false;
4854 bool use_cluster = true;
4855 u64 ideal_cache_percent = 0;
4856 u64 ideal_cache_offset = 0;
4858 WARN_ON(num_bytes < root->sectorsize);
4859 btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
4863 space_info = __find_space_info(root->fs_info, data);
4865 printk(KERN_ERR "No space info for %d\n", data);
4870 * If the space info is for both data and metadata it means we have a
4871 * small filesystem and we can't use the clustering stuff.
4873 if (btrfs_mixed_space_info(space_info))
4874 use_cluster = false;
4876 if (orig_root->ref_cows || empty_size)
4877 allowed_chunk_alloc = 1;
4879 if (data & BTRFS_BLOCK_GROUP_METADATA && use_cluster) {
4880 last_ptr = &root->fs_info->meta_alloc_cluster;
4881 if (!btrfs_test_opt(root, SSD))
4882 empty_cluster = 64 * 1024;
4885 if ((data & BTRFS_BLOCK_GROUP_DATA) && use_cluster &&
4886 btrfs_test_opt(root, SSD)) {
4887 last_ptr = &root->fs_info->data_alloc_cluster;
4891 spin_lock(&last_ptr->lock);
4892 if (last_ptr->block_group)
4893 hint_byte = last_ptr->window_start;
4894 spin_unlock(&last_ptr->lock);
4897 search_start = max(search_start, first_logical_byte(root, 0));
4898 search_start = max(search_start, hint_byte);
4903 if (search_start == hint_byte) {
4905 block_group = btrfs_lookup_block_group(root->fs_info,
4908 * we don't want to use the block group if it doesn't match our
4909 * allocation bits, or if its not cached.
4911 * However if we are re-searching with an ideal block group
4912 * picked out then we don't care that the block group is cached.
4914 if (block_group && block_group_bits(block_group, data) &&
4915 (block_group->cached != BTRFS_CACHE_NO ||
4916 search_start == ideal_cache_offset)) {
4917 down_read(&space_info->groups_sem);
4918 if (list_empty(&block_group->list) ||
4921 * someone is removing this block group,
4922 * we can't jump into the have_block_group
4923 * target because our list pointers are not
4926 btrfs_put_block_group(block_group);
4927 up_read(&space_info->groups_sem);
4929 index = get_block_group_index(block_group);
4930 goto have_block_group;
4932 } else if (block_group) {
4933 btrfs_put_block_group(block_group);
4937 down_read(&space_info->groups_sem);
4938 list_for_each_entry(block_group, &space_info->block_groups[index],
4943 btrfs_get_block_group(block_group);
4944 search_start = block_group->key.objectid;
4947 * this can happen if we end up cycling through all the
4948 * raid types, but we want to make sure we only allocate
4949 * for the proper type.
4951 if (!block_group_bits(block_group, data)) {
4952 u64 extra = BTRFS_BLOCK_GROUP_DUP |
4953 BTRFS_BLOCK_GROUP_RAID1 |
4954 BTRFS_BLOCK_GROUP_RAID10;
4957 * if they asked for extra copies and this block group
4958 * doesn't provide them, bail. This does allow us to
4959 * fill raid0 from raid1.
4961 if ((data & extra) && !(block_group->flags & extra))
4966 if (unlikely(block_group->cached == BTRFS_CACHE_NO)) {
4969 ret = cache_block_group(block_group, trans,
4971 if (block_group->cached == BTRFS_CACHE_FINISHED)
4972 goto have_block_group;
4974 free_percent = btrfs_block_group_used(&block_group->item);
4975 free_percent *= 100;
4976 free_percent = div64_u64(free_percent,
4977 block_group->key.offset);
4978 free_percent = 100 - free_percent;
4979 if (free_percent > ideal_cache_percent &&
4980 likely(!block_group->ro)) {
4981 ideal_cache_offset = block_group->key.objectid;
4982 ideal_cache_percent = free_percent;
4986 * We only want to start kthread caching if we are at
4987 * the point where we will wait for caching to make
4988 * progress, or if our ideal search is over and we've
4989 * found somebody to start caching.
4991 if (loop > LOOP_CACHING_NOWAIT ||
4992 (loop > LOOP_FIND_IDEAL &&
4993 atomic_read(&space_info->caching_threads) < 2)) {
4994 ret = cache_block_group(block_group, trans,
4998 found_uncached_bg = true;
5001 * If loop is set for cached only, try the next block
5004 if (loop == LOOP_FIND_IDEAL)
5008 cached = block_group_cache_done(block_group);
5009 if (unlikely(!cached))
5010 found_uncached_bg = true;
5012 if (unlikely(block_group->ro))
5016 * Ok we want to try and use the cluster allocator, so lets look
5017 * there, unless we are on LOOP_NO_EMPTY_SIZE, since we will
5018 * have tried the cluster allocator plenty of times at this
5019 * point and not have found anything, so we are likely way too
5020 * fragmented for the clustering stuff to find anything, so lets
5021 * just skip it and let the allocator find whatever block it can
5024 if (last_ptr && loop < LOOP_NO_EMPTY_SIZE) {
5026 * the refill lock keeps out other
5027 * people trying to start a new cluster
5029 spin_lock(&last_ptr->refill_lock);
5030 if (last_ptr->block_group &&
5031 (last_ptr->block_group->ro ||
5032 !block_group_bits(last_ptr->block_group, data))) {
5034 goto refill_cluster;
5037 offset = btrfs_alloc_from_cluster(block_group, last_ptr,
5038 num_bytes, search_start);
5040 /* we have a block, we're done */
5041 spin_unlock(&last_ptr->refill_lock);
5045 spin_lock(&last_ptr->lock);
5047 * whoops, this cluster doesn't actually point to
5048 * this block group. Get a ref on the block
5049 * group is does point to and try again
5051 if (!last_ptr_loop && last_ptr->block_group &&
5052 last_ptr->block_group != block_group) {
5054 btrfs_put_block_group(block_group);
5055 block_group = last_ptr->block_group;
5056 btrfs_get_block_group(block_group);
5057 spin_unlock(&last_ptr->lock);
5058 spin_unlock(&last_ptr->refill_lock);
5061 search_start = block_group->key.objectid;
5063 * we know this block group is properly
5064 * in the list because
5065 * btrfs_remove_block_group, drops the
5066 * cluster before it removes the block
5067 * group from the list
5069 goto have_block_group;
5071 spin_unlock(&last_ptr->lock);
5074 * this cluster didn't work out, free it and
5077 btrfs_return_cluster_to_free_space(NULL, last_ptr);
5081 /* allocate a cluster in this block group */
5082 ret = btrfs_find_space_cluster(trans, root,
5083 block_group, last_ptr,
5085 empty_cluster + empty_size);
5088 * now pull our allocation out of this
5091 offset = btrfs_alloc_from_cluster(block_group,
5092 last_ptr, num_bytes,
5095 /* we found one, proceed */
5096 spin_unlock(&last_ptr->refill_lock);
5099 } else if (!cached && loop > LOOP_CACHING_NOWAIT
5100 && !failed_cluster_refill) {
5101 spin_unlock(&last_ptr->refill_lock);
5103 failed_cluster_refill = true;
5104 wait_block_group_cache_progress(block_group,
5105 num_bytes + empty_cluster + empty_size);
5106 goto have_block_group;
5110 * at this point we either didn't find a cluster
5111 * or we weren't able to allocate a block from our
5112 * cluster. Free the cluster we've been trying
5113 * to use, and go to the next block group
5115 btrfs_return_cluster_to_free_space(NULL, last_ptr);
5116 spin_unlock(&last_ptr->refill_lock);
5120 offset = btrfs_find_space_for_alloc(block_group, search_start,
5121 num_bytes, empty_size);
5123 * If we didn't find a chunk, and we haven't failed on this
5124 * block group before, and this block group is in the middle of
5125 * caching and we are ok with waiting, then go ahead and wait
5126 * for progress to be made, and set failed_alloc to true.
5128 * If failed_alloc is true then we've already waited on this
5129 * block group once and should move on to the next block group.
5131 if (!offset && !failed_alloc && !cached &&
5132 loop > LOOP_CACHING_NOWAIT) {
5133 wait_block_group_cache_progress(block_group,
5134 num_bytes + empty_size);
5135 failed_alloc = true;
5136 goto have_block_group;
5137 } else if (!offset) {
5141 search_start = stripe_align(root, offset);
5142 /* move on to the next group */
5143 if (search_start + num_bytes >= search_end) {
5144 btrfs_add_free_space(block_group, offset, num_bytes);
5148 /* move on to the next group */
5149 if (search_start + num_bytes >
5150 block_group->key.objectid + block_group->key.offset) {
5151 btrfs_add_free_space(block_group, offset, num_bytes);
5155 ins->objectid = search_start;
5156 ins->offset = num_bytes;
5158 if (offset < search_start)
5159 btrfs_add_free_space(block_group, offset,
5160 search_start - offset);
5161 BUG_ON(offset > search_start);
5163 ret = update_reserved_bytes(block_group, num_bytes, 1,
5164 (data & BTRFS_BLOCK_GROUP_DATA));
5165 if (ret == -EAGAIN) {
5166 btrfs_add_free_space(block_group, offset, num_bytes);
5170 /* we are all good, lets return */
5171 ins->objectid = search_start;
5172 ins->offset = num_bytes;
5174 if (offset < search_start)
5175 btrfs_add_free_space(block_group, offset,
5176 search_start - offset);
5177 BUG_ON(offset > search_start);
5180 failed_cluster_refill = false;
5181 failed_alloc = false;
5182 BUG_ON(index != get_block_group_index(block_group));
5183 btrfs_put_block_group(block_group);
5185 up_read(&space_info->groups_sem);
5187 if (!ins->objectid && ++index < BTRFS_NR_RAID_TYPES)
5190 /* LOOP_FIND_IDEAL, only search caching/cached bg's, and don't wait for
5191 * for them to make caching progress. Also
5192 * determine the best possible bg to cache
5193 * LOOP_CACHING_NOWAIT, search partially cached block groups, kicking
5194 * caching kthreads as we move along
5195 * LOOP_CACHING_WAIT, search everything, and wait if our bg is caching
5196 * LOOP_ALLOC_CHUNK, force a chunk allocation and try again
5197 * LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try
5200 if (!ins->objectid && loop < LOOP_NO_EMPTY_SIZE &&
5201 (found_uncached_bg || empty_size || empty_cluster ||
5202 allowed_chunk_alloc)) {
5204 if (loop == LOOP_FIND_IDEAL && found_uncached_bg) {
5205 found_uncached_bg = false;
5207 if (!ideal_cache_percent &&
5208 atomic_read(&space_info->caching_threads))
5212 * 1 of the following 2 things have happened so far
5214 * 1) We found an ideal block group for caching that
5215 * is mostly full and will cache quickly, so we might
5216 * as well wait for it.
5218 * 2) We searched for cached only and we didn't find
5219 * anything, and we didn't start any caching kthreads
5220 * either, so chances are we will loop through and
5221 * start a couple caching kthreads, and then come back
5222 * around and just wait for them. This will be slower
5223 * because we will have 2 caching kthreads reading at
5224 * the same time when we could have just started one
5225 * and waited for it to get far enough to give us an
5226 * allocation, so go ahead and go to the wait caching
5229 loop = LOOP_CACHING_WAIT;
5230 search_start = ideal_cache_offset;
5231 ideal_cache_percent = 0;
5233 } else if (loop == LOOP_FIND_IDEAL) {
5235 * Didn't find a uncached bg, wait on anything we find
5238 loop = LOOP_CACHING_WAIT;
5242 if (loop < LOOP_CACHING_WAIT) {
5247 if (loop == LOOP_ALLOC_CHUNK) {
5252 if (allowed_chunk_alloc) {
5253 ret = do_chunk_alloc(trans, root, num_bytes +
5254 2 * 1024 * 1024, data, 1);
5255 allowed_chunk_alloc = 0;
5256 done_chunk_alloc = 1;
5257 } else if (!done_chunk_alloc) {
5258 space_info->force_alloc = 1;
5261 if (loop < LOOP_NO_EMPTY_SIZE) {
5266 } else if (!ins->objectid) {
5270 /* we found what we needed */
5271 if (ins->objectid) {
5272 if (!(data & BTRFS_BLOCK_GROUP_DATA))
5273 trans->block_group = block_group->key.objectid;
5275 btrfs_put_block_group(block_group);
5282 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
5283 int dump_block_groups)
5285 struct btrfs_block_group_cache *cache;
5288 spin_lock(&info->lock);
5289 printk(KERN_INFO "space_info has %llu free, is %sfull\n",
5290 (unsigned long long)(info->total_bytes - info->bytes_used -
5291 info->bytes_pinned - info->bytes_reserved -
5292 info->bytes_readonly),
5293 (info->full) ? "" : "not ");
5294 printk(KERN_INFO "space_info total=%llu, used=%llu, pinned=%llu, "
5295 "reserved=%llu, may_use=%llu, readonly=%llu\n",
5296 (unsigned long long)info->total_bytes,
5297 (unsigned long long)info->bytes_used,
5298 (unsigned long long)info->bytes_pinned,
5299 (unsigned long long)info->bytes_reserved,
5300 (unsigned long long)info->bytes_may_use,
5301 (unsigned long long)info->bytes_readonly);
5302 spin_unlock(&info->lock);
5304 if (!dump_block_groups)
5307 down_read(&info->groups_sem);
5309 list_for_each_entry(cache, &info->block_groups[index], list) {
5310 spin_lock(&cache->lock);
5311 printk(KERN_INFO "block group %llu has %llu bytes, %llu used "
5312 "%llu pinned %llu reserved\n",
5313 (unsigned long long)cache->key.objectid,
5314 (unsigned long long)cache->key.offset,
5315 (unsigned long long)btrfs_block_group_used(&cache->item),
5316 (unsigned long long)cache->pinned,
5317 (unsigned long long)cache->reserved);
5318 btrfs_dump_free_space(cache, bytes);
5319 spin_unlock(&cache->lock);
5321 if (++index < BTRFS_NR_RAID_TYPES)
5323 up_read(&info->groups_sem);
5326 int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
5327 struct btrfs_root *root,
5328 u64 num_bytes, u64 min_alloc_size,
5329 u64 empty_size, u64 hint_byte,
5330 u64 search_end, struct btrfs_key *ins,
5334 u64 search_start = 0;
5336 data = btrfs_get_alloc_profile(root, data);
5339 * the only place that sets empty_size is btrfs_realloc_node, which
5340 * is not called recursively on allocations
5342 if (empty_size || root->ref_cows)
5343 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
5344 num_bytes + 2 * 1024 * 1024, data, 0);
5346 WARN_ON(num_bytes < root->sectorsize);
5347 ret = find_free_extent(trans, root, num_bytes, empty_size,
5348 search_start, search_end, hint_byte,
5351 if (ret == -ENOSPC && num_bytes > min_alloc_size) {
5352 num_bytes = num_bytes >> 1;
5353 num_bytes = num_bytes & ~(root->sectorsize - 1);
5354 num_bytes = max(num_bytes, min_alloc_size);
5355 do_chunk_alloc(trans, root->fs_info->extent_root,
5356 num_bytes, data, 1);
5359 if (ret == -ENOSPC) {
5360 struct btrfs_space_info *sinfo;
5362 sinfo = __find_space_info(root->fs_info, data);
5363 printk(KERN_ERR "btrfs allocation failed flags %llu, "
5364 "wanted %llu\n", (unsigned long long)data,
5365 (unsigned long long)num_bytes);
5366 dump_space_info(sinfo, num_bytes, 1);
5372 int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len)
5374 struct btrfs_block_group_cache *cache;
5377 cache = btrfs_lookup_block_group(root->fs_info, start);
5379 printk(KERN_ERR "Unable to find block group for %llu\n",
5380 (unsigned long long)start);
5384 ret = btrfs_discard_extent(root, start, len);
5386 btrfs_add_free_space(cache, start, len);
5387 update_reserved_bytes(cache, len, 0, 1);
5388 btrfs_put_block_group(cache);
5393 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
5394 struct btrfs_root *root,
5395 u64 parent, u64 root_objectid,
5396 u64 flags, u64 owner, u64 offset,
5397 struct btrfs_key *ins, int ref_mod)
5400 struct btrfs_fs_info *fs_info = root->fs_info;
5401 struct btrfs_extent_item *extent_item;
5402 struct btrfs_extent_inline_ref *iref;
5403 struct btrfs_path *path;
5404 struct extent_buffer *leaf;
5409 type = BTRFS_SHARED_DATA_REF_KEY;
5411 type = BTRFS_EXTENT_DATA_REF_KEY;
5413 size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type);
5415 path = btrfs_alloc_path();
5418 path->leave_spinning = 1;
5419 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
5423 leaf = path->nodes[0];
5424 extent_item = btrfs_item_ptr(leaf, path->slots[0],
5425 struct btrfs_extent_item);
5426 btrfs_set_extent_refs(leaf, extent_item, ref_mod);
5427 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
5428 btrfs_set_extent_flags(leaf, extent_item,
5429 flags | BTRFS_EXTENT_FLAG_DATA);
5431 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
5432 btrfs_set_extent_inline_ref_type(leaf, iref, type);
5434 struct btrfs_shared_data_ref *ref;
5435 ref = (struct btrfs_shared_data_ref *)(iref + 1);
5436 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
5437 btrfs_set_shared_data_ref_count(leaf, ref, ref_mod);
5439 struct btrfs_extent_data_ref *ref;
5440 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
5441 btrfs_set_extent_data_ref_root(leaf, ref, root_objectid);
5442 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
5443 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
5444 btrfs_set_extent_data_ref_count(leaf, ref, ref_mod);
5447 btrfs_mark_buffer_dirty(path->nodes[0]);
5448 btrfs_free_path(path);
5450 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
5452 printk(KERN_ERR "btrfs update block group failed for %llu "
5453 "%llu\n", (unsigned long long)ins->objectid,
5454 (unsigned long long)ins->offset);
5460 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
5461 struct btrfs_root *root,
5462 u64 parent, u64 root_objectid,
5463 u64 flags, struct btrfs_disk_key *key,
5464 int level, struct btrfs_key *ins)
5467 struct btrfs_fs_info *fs_info = root->fs_info;
5468 struct btrfs_extent_item *extent_item;
5469 struct btrfs_tree_block_info *block_info;
5470 struct btrfs_extent_inline_ref *iref;
5471 struct btrfs_path *path;
5472 struct extent_buffer *leaf;
5473 u32 size = sizeof(*extent_item) + sizeof(*block_info) + sizeof(*iref);
5475 path = btrfs_alloc_path();
5478 path->leave_spinning = 1;
5479 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
5483 leaf = path->nodes[0];
5484 extent_item = btrfs_item_ptr(leaf, path->slots[0],
5485 struct btrfs_extent_item);
5486 btrfs_set_extent_refs(leaf, extent_item, 1);
5487 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
5488 btrfs_set_extent_flags(leaf, extent_item,
5489 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
5490 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
5492 btrfs_set_tree_block_key(leaf, block_info, key);
5493 btrfs_set_tree_block_level(leaf, block_info, level);
5495 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
5497 BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF));
5498 btrfs_set_extent_inline_ref_type(leaf, iref,
5499 BTRFS_SHARED_BLOCK_REF_KEY);
5500 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
5502 btrfs_set_extent_inline_ref_type(leaf, iref,
5503 BTRFS_TREE_BLOCK_REF_KEY);
5504 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
5507 btrfs_mark_buffer_dirty(leaf);
5508 btrfs_free_path(path);
5510 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
5512 printk(KERN_ERR "btrfs update block group failed for %llu "
5513 "%llu\n", (unsigned long long)ins->objectid,
5514 (unsigned long long)ins->offset);
5520 int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
5521 struct btrfs_root *root,
5522 u64 root_objectid, u64 owner,
5523 u64 offset, struct btrfs_key *ins)
5527 BUG_ON(root_objectid == BTRFS_TREE_LOG_OBJECTID);
5529 ret = btrfs_add_delayed_data_ref(trans, ins->objectid, ins->offset,
5530 0, root_objectid, owner, offset,
5531 BTRFS_ADD_DELAYED_EXTENT, NULL);
5536 * this is used by the tree logging recovery code. It records that
5537 * an extent has been allocated and makes sure to clear the free
5538 * space cache bits as well
5540 int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
5541 struct btrfs_root *root,
5542 u64 root_objectid, u64 owner, u64 offset,
5543 struct btrfs_key *ins)
5546 struct btrfs_block_group_cache *block_group;
5547 struct btrfs_caching_control *caching_ctl;
5548 u64 start = ins->objectid;
5549 u64 num_bytes = ins->offset;
5551 block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
5552 cache_block_group(block_group, trans, NULL, 0);
5553 caching_ctl = get_caching_control(block_group);
5556 BUG_ON(!block_group_cache_done(block_group));
5557 ret = btrfs_remove_free_space(block_group, start, num_bytes);
5560 mutex_lock(&caching_ctl->mutex);
5562 if (start >= caching_ctl->progress) {
5563 ret = add_excluded_extent(root, start, num_bytes);
5565 } else if (start + num_bytes <= caching_ctl->progress) {
5566 ret = btrfs_remove_free_space(block_group,
5570 num_bytes = caching_ctl->progress - start;
5571 ret = btrfs_remove_free_space(block_group,
5575 start = caching_ctl->progress;
5576 num_bytes = ins->objectid + ins->offset -
5577 caching_ctl->progress;
5578 ret = add_excluded_extent(root, start, num_bytes);
5582 mutex_unlock(&caching_ctl->mutex);
5583 put_caching_control(caching_ctl);
5586 ret = update_reserved_bytes(block_group, ins->offset, 1, 1);
5588 btrfs_put_block_group(block_group);
5589 ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,
5590 0, owner, offset, ins, 1);
5594 struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
5595 struct btrfs_root *root,
5596 u64 bytenr, u32 blocksize,
5599 struct extent_buffer *buf;
5601 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
5603 return ERR_PTR(-ENOMEM);
5604 btrfs_set_header_generation(buf, trans->transid);
5605 btrfs_set_buffer_lockdep_class(buf, level);
5606 btrfs_tree_lock(buf);
5607 clean_tree_block(trans, root, buf);
5609 btrfs_set_lock_blocking(buf);
5610 btrfs_set_buffer_uptodate(buf);
5612 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
5614 * we allow two log transactions at a time, use different
5615 * EXENT bit to differentiate dirty pages.
5617 if (root->log_transid % 2 == 0)
5618 set_extent_dirty(&root->dirty_log_pages, buf->start,
5619 buf->start + buf->len - 1, GFP_NOFS);
5621 set_extent_new(&root->dirty_log_pages, buf->start,
5622 buf->start + buf->len - 1, GFP_NOFS);
5624 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
5625 buf->start + buf->len - 1, GFP_NOFS);
5627 trans->blocks_used++;
5628 /* this returns a buffer locked for blocking */
5632 static struct btrfs_block_rsv *
5633 use_block_rsv(struct btrfs_trans_handle *trans,
5634 struct btrfs_root *root, u32 blocksize)
5636 struct btrfs_block_rsv *block_rsv;
5639 block_rsv = get_block_rsv(trans, root);
5641 if (block_rsv->size == 0) {
5642 ret = reserve_metadata_bytes(trans, root, block_rsv,
5645 return ERR_PTR(ret);
5649 ret = block_rsv_use_bytes(block_rsv, blocksize);
5653 return ERR_PTR(-ENOSPC);
5656 static void unuse_block_rsv(struct btrfs_block_rsv *block_rsv, u32 blocksize)
5658 block_rsv_add_bytes(block_rsv, blocksize, 0);
5659 block_rsv_release_bytes(block_rsv, NULL, 0);
5663 * finds a free extent and does all the dirty work required for allocation
5664 * returns the key for the extent through ins, and a tree buffer for
5665 * the first block of the extent through buf.
5667 * returns the tree buffer or NULL.
5669 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
5670 struct btrfs_root *root, u32 blocksize,
5671 u64 parent, u64 root_objectid,
5672 struct btrfs_disk_key *key, int level,
5673 u64 hint, u64 empty_size)
5675 struct btrfs_key ins;
5676 struct btrfs_block_rsv *block_rsv;
5677 struct extent_buffer *buf;
5682 block_rsv = use_block_rsv(trans, root, blocksize);
5683 if (IS_ERR(block_rsv))
5684 return ERR_CAST(block_rsv);
5686 ret = btrfs_reserve_extent(trans, root, blocksize, blocksize,
5687 empty_size, hint, (u64)-1, &ins, 0);
5689 unuse_block_rsv(block_rsv, blocksize);
5690 return ERR_PTR(ret);
5693 buf = btrfs_init_new_buffer(trans, root, ins.objectid,
5695 BUG_ON(IS_ERR(buf));
5697 if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
5699 parent = ins.objectid;
5700 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
5704 if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
5705 struct btrfs_delayed_extent_op *extent_op;
5706 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
5709 memcpy(&extent_op->key, key, sizeof(extent_op->key));
5711 memset(&extent_op->key, 0, sizeof(extent_op->key));
5712 extent_op->flags_to_set = flags;
5713 extent_op->update_key = 1;
5714 extent_op->update_flags = 1;
5715 extent_op->is_data = 0;
5717 ret = btrfs_add_delayed_tree_ref(trans, ins.objectid,
5718 ins.offset, parent, root_objectid,
5719 level, BTRFS_ADD_DELAYED_EXTENT,
5726 struct walk_control {
5727 u64 refs[BTRFS_MAX_LEVEL];
5728 u64 flags[BTRFS_MAX_LEVEL];
5729 struct btrfs_key update_progress;
5739 #define DROP_REFERENCE 1
5740 #define UPDATE_BACKREF 2
5742 static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
5743 struct btrfs_root *root,
5744 struct walk_control *wc,
5745 struct btrfs_path *path)
5753 struct btrfs_key key;
5754 struct extent_buffer *eb;
5759 if (path->slots[wc->level] < wc->reada_slot) {
5760 wc->reada_count = wc->reada_count * 2 / 3;
5761 wc->reada_count = max(wc->reada_count, 2);
5763 wc->reada_count = wc->reada_count * 3 / 2;
5764 wc->reada_count = min_t(int, wc->reada_count,
5765 BTRFS_NODEPTRS_PER_BLOCK(root));
5768 eb = path->nodes[wc->level];
5769 nritems = btrfs_header_nritems(eb);
5770 blocksize = btrfs_level_size(root, wc->level - 1);
5772 for (slot = path->slots[wc->level]; slot < nritems; slot++) {
5773 if (nread >= wc->reada_count)
5777 bytenr = btrfs_node_blockptr(eb, slot);
5778 generation = btrfs_node_ptr_generation(eb, slot);
5780 if (slot == path->slots[wc->level])
5783 if (wc->stage == UPDATE_BACKREF &&
5784 generation <= root->root_key.offset)
5787 /* We don't lock the tree block, it's OK to be racy here */
5788 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
5793 if (wc->stage == DROP_REFERENCE) {
5797 if (wc->level == 1 &&
5798 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5800 if (!wc->update_ref ||
5801 generation <= root->root_key.offset)
5803 btrfs_node_key_to_cpu(eb, &key, slot);
5804 ret = btrfs_comp_cpu_keys(&key,
5805 &wc->update_progress);
5809 if (wc->level == 1 &&
5810 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5814 ret = readahead_tree_block(root, bytenr, blocksize,
5820 wc->reada_slot = slot;
5824 * hepler to process tree block while walking down the tree.
5826 * when wc->stage == UPDATE_BACKREF, this function updates
5827 * back refs for pointers in the block.
5829 * NOTE: return value 1 means we should stop walking down.
5831 static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
5832 struct btrfs_root *root,
5833 struct btrfs_path *path,
5834 struct walk_control *wc, int lookup_info)
5836 int level = wc->level;
5837 struct extent_buffer *eb = path->nodes[level];
5838 u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF;
5841 if (wc->stage == UPDATE_BACKREF &&
5842 btrfs_header_owner(eb) != root->root_key.objectid)
5846 * when reference count of tree block is 1, it won't increase
5847 * again. once full backref flag is set, we never clear it.
5850 ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
5851 (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag)))) {
5852 BUG_ON(!path->locks[level]);
5853 ret = btrfs_lookup_extent_info(trans, root,
5858 BUG_ON(wc->refs[level] == 0);
5861 if (wc->stage == DROP_REFERENCE) {
5862 if (wc->refs[level] > 1)
5865 if (path->locks[level] && !wc->keep_locks) {
5866 btrfs_tree_unlock(eb);
5867 path->locks[level] = 0;
5872 /* wc->stage == UPDATE_BACKREF */
5873 if (!(wc->flags[level] & flag)) {
5874 BUG_ON(!path->locks[level]);
5875 ret = btrfs_inc_ref(trans, root, eb, 1);
5877 ret = btrfs_dec_ref(trans, root, eb, 0);
5879 ret = btrfs_set_disk_extent_flags(trans, root, eb->start,
5882 wc->flags[level] |= flag;
5886 * the block is shared by multiple trees, so it's not good to
5887 * keep the tree lock
5889 if (path->locks[level] && level > 0) {
5890 btrfs_tree_unlock(eb);
5891 path->locks[level] = 0;
5897 * hepler to process tree block pointer.
5899 * when wc->stage == DROP_REFERENCE, this function checks
5900 * reference count of the block pointed to. if the block
5901 * is shared and we need update back refs for the subtree
5902 * rooted at the block, this function changes wc->stage to
5903 * UPDATE_BACKREF. if the block is shared and there is no
5904 * need to update back, this function drops the reference
5907 * NOTE: return value 1 means we should stop walking down.
5909 static noinline int do_walk_down(struct btrfs_trans_handle *trans,
5910 struct btrfs_root *root,
5911 struct btrfs_path *path,
5912 struct walk_control *wc, int *lookup_info)
5918 struct btrfs_key key;
5919 struct extent_buffer *next;
5920 int level = wc->level;
5924 generation = btrfs_node_ptr_generation(path->nodes[level],
5925 path->slots[level]);
5927 * if the lower level block was created before the snapshot
5928 * was created, we know there is no need to update back refs
5931 if (wc->stage == UPDATE_BACKREF &&
5932 generation <= root->root_key.offset) {
5937 bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]);
5938 blocksize = btrfs_level_size(root, level - 1);
5940 next = btrfs_find_tree_block(root, bytenr, blocksize);
5942 next = btrfs_find_create_tree_block(root, bytenr, blocksize);
5947 btrfs_tree_lock(next);
5948 btrfs_set_lock_blocking(next);
5950 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
5951 &wc->refs[level - 1],
5952 &wc->flags[level - 1]);
5954 BUG_ON(wc->refs[level - 1] == 0);
5957 if (wc->stage == DROP_REFERENCE) {
5958 if (wc->refs[level - 1] > 1) {
5960 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5963 if (!wc->update_ref ||
5964 generation <= root->root_key.offset)
5967 btrfs_node_key_to_cpu(path->nodes[level], &key,
5968 path->slots[level]);
5969 ret = btrfs_comp_cpu_keys(&key, &wc->update_progress);
5973 wc->stage = UPDATE_BACKREF;
5974 wc->shared_level = level - 1;
5978 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5982 if (!btrfs_buffer_uptodate(next, generation)) {
5983 btrfs_tree_unlock(next);
5984 free_extent_buffer(next);
5990 if (reada && level == 1)
5991 reada_walk_down(trans, root, wc, path);
5992 next = read_tree_block(root, bytenr, blocksize, generation);
5993 btrfs_tree_lock(next);
5994 btrfs_set_lock_blocking(next);
5998 BUG_ON(level != btrfs_header_level(next));
5999 path->nodes[level] = next;
6000 path->slots[level] = 0;
6001 path->locks[level] = 1;
6007 wc->refs[level - 1] = 0;
6008 wc->flags[level - 1] = 0;
6009 if (wc->stage == DROP_REFERENCE) {
6010 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
6011 parent = path->nodes[level]->start;
6013 BUG_ON(root->root_key.objectid !=
6014 btrfs_header_owner(path->nodes[level]));
6018 ret = btrfs_free_extent(trans, root, bytenr, blocksize, parent,
6019 root->root_key.objectid, level - 1, 0);
6022 btrfs_tree_unlock(next);
6023 free_extent_buffer(next);
6029 * hepler to process tree block while walking up the tree.
6031 * when wc->stage == DROP_REFERENCE, this function drops
6032 * reference count on the block.
6034 * when wc->stage == UPDATE_BACKREF, this function changes
6035 * wc->stage back to DROP_REFERENCE if we changed wc->stage
6036 * to UPDATE_BACKREF previously while processing the block.
6038 * NOTE: return value 1 means we should stop walking up.
6040 static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
6041 struct btrfs_root *root,
6042 struct btrfs_path *path,
6043 struct walk_control *wc)
6046 int level = wc->level;
6047 struct extent_buffer *eb = path->nodes[level];
6050 if (wc->stage == UPDATE_BACKREF) {
6051 BUG_ON(wc->shared_level < level);
6052 if (level < wc->shared_level)
6055 ret = find_next_key(path, level + 1, &wc->update_progress);
6059 wc->stage = DROP_REFERENCE;
6060 wc->shared_level = -1;
6061 path->slots[level] = 0;
6064 * check reference count again if the block isn't locked.
6065 * we should start walking down the tree again if reference
6068 if (!path->locks[level]) {
6070 btrfs_tree_lock(eb);
6071 btrfs_set_lock_blocking(eb);
6072 path->locks[level] = 1;
6074 ret = btrfs_lookup_extent_info(trans, root,
6079 BUG_ON(wc->refs[level] == 0);
6080 if (wc->refs[level] == 1) {
6081 btrfs_tree_unlock(eb);
6082 path->locks[level] = 0;
6088 /* wc->stage == DROP_REFERENCE */
6089 BUG_ON(wc->refs[level] > 1 && !path->locks[level]);
6091 if (wc->refs[level] == 1) {
6093 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6094 ret = btrfs_dec_ref(trans, root, eb, 1);
6096 ret = btrfs_dec_ref(trans, root, eb, 0);
6099 /* make block locked assertion in clean_tree_block happy */
6100 if (!path->locks[level] &&
6101 btrfs_header_generation(eb) == trans->transid) {
6102 btrfs_tree_lock(eb);
6103 btrfs_set_lock_blocking(eb);
6104 path->locks[level] = 1;
6106 clean_tree_block(trans, root, eb);
6109 if (eb == root->node) {
6110 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6113 BUG_ON(root->root_key.objectid !=
6114 btrfs_header_owner(eb));
6116 if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
6117 parent = path->nodes[level + 1]->start;
6119 BUG_ON(root->root_key.objectid !=
6120 btrfs_header_owner(path->nodes[level + 1]));
6123 btrfs_free_tree_block(trans, root, eb, parent, wc->refs[level] == 1);
6125 wc->refs[level] = 0;
6126 wc->flags[level] = 0;
6130 static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
6131 struct btrfs_root *root,
6132 struct btrfs_path *path,
6133 struct walk_control *wc)
6135 int level = wc->level;
6136 int lookup_info = 1;
6139 while (level >= 0) {
6140 ret = walk_down_proc(trans, root, path, wc, lookup_info);
6147 if (path->slots[level] >=
6148 btrfs_header_nritems(path->nodes[level]))
6151 ret = do_walk_down(trans, root, path, wc, &lookup_info);
6153 path->slots[level]++;
6162 static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
6163 struct btrfs_root *root,
6164 struct btrfs_path *path,
6165 struct walk_control *wc, int max_level)
6167 int level = wc->level;
6170 path->slots[level] = btrfs_header_nritems(path->nodes[level]);
6171 while (level < max_level && path->nodes[level]) {
6173 if (path->slots[level] + 1 <
6174 btrfs_header_nritems(path->nodes[level])) {
6175 path->slots[level]++;
6178 ret = walk_up_proc(trans, root, path, wc);
6182 if (path->locks[level]) {
6183 btrfs_tree_unlock(path->nodes[level]);
6184 path->locks[level] = 0;
6186 free_extent_buffer(path->nodes[level]);
6187 path->nodes[level] = NULL;
6195 * drop a subvolume tree.
6197 * this function traverses the tree freeing any blocks that only
6198 * referenced by the tree.
6200 * when a shared tree block is found. this function decreases its
6201 * reference count by one. if update_ref is true, this function
6202 * also make sure backrefs for the shared block and all lower level
6203 * blocks are properly updated.
6205 int btrfs_drop_snapshot(struct btrfs_root *root,
6206 struct btrfs_block_rsv *block_rsv, int update_ref)
6208 struct btrfs_path *path;
6209 struct btrfs_trans_handle *trans;
6210 struct btrfs_root *tree_root = root->fs_info->tree_root;
6211 struct btrfs_root_item *root_item = &root->root_item;
6212 struct walk_control *wc;
6213 struct btrfs_key key;
6218 path = btrfs_alloc_path();
6221 wc = kzalloc(sizeof(*wc), GFP_NOFS);
6224 trans = btrfs_start_transaction(tree_root, 0);
6226 trans->block_rsv = block_rsv;
6228 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
6229 level = btrfs_header_level(root->node);
6230 path->nodes[level] = btrfs_lock_root_node(root);
6231 btrfs_set_lock_blocking(path->nodes[level]);
6232 path->slots[level] = 0;
6233 path->locks[level] = 1;
6234 memset(&wc->update_progress, 0,
6235 sizeof(wc->update_progress));
6237 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
6238 memcpy(&wc->update_progress, &key,
6239 sizeof(wc->update_progress));
6241 level = root_item->drop_level;
6243 path->lowest_level = level;
6244 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6245 path->lowest_level = 0;
6253 * unlock our path, this is safe because only this
6254 * function is allowed to delete this snapshot
6256 btrfs_unlock_up_safe(path, 0);
6258 level = btrfs_header_level(root->node);
6260 btrfs_tree_lock(path->nodes[level]);
6261 btrfs_set_lock_blocking(path->nodes[level]);
6263 ret = btrfs_lookup_extent_info(trans, root,
6264 path->nodes[level]->start,
6265 path->nodes[level]->len,
6269 BUG_ON(wc->refs[level] == 0);
6271 if (level == root_item->drop_level)
6274 btrfs_tree_unlock(path->nodes[level]);
6275 WARN_ON(wc->refs[level] != 1);
6281 wc->shared_level = -1;
6282 wc->stage = DROP_REFERENCE;
6283 wc->update_ref = update_ref;
6285 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
6288 ret = walk_down_tree(trans, root, path, wc);
6294 ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL);
6301 BUG_ON(wc->stage != DROP_REFERENCE);
6305 if (wc->stage == DROP_REFERENCE) {
6307 btrfs_node_key(path->nodes[level],
6308 &root_item->drop_progress,
6309 path->slots[level]);
6310 root_item->drop_level = level;
6313 BUG_ON(wc->level == 0);
6314 if (btrfs_should_end_transaction(trans, tree_root)) {
6315 ret = btrfs_update_root(trans, tree_root,
6320 btrfs_end_transaction_throttle(trans, tree_root);
6321 trans = btrfs_start_transaction(tree_root, 0);
6323 trans->block_rsv = block_rsv;
6326 btrfs_release_path(root, path);
6329 ret = btrfs_del_root(trans, tree_root, &root->root_key);
6332 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
6333 ret = btrfs_find_last_root(tree_root, root->root_key.objectid,
6337 /* if we fail to delete the orphan item this time
6338 * around, it'll get picked up the next time.
6340 * The most common failure here is just -ENOENT.
6342 btrfs_del_orphan_item(trans, tree_root,
6343 root->root_key.objectid);
6347 if (root->in_radix) {
6348 btrfs_free_fs_root(tree_root->fs_info, root);
6350 free_extent_buffer(root->node);
6351 free_extent_buffer(root->commit_root);
6355 btrfs_end_transaction_throttle(trans, tree_root);
6357 btrfs_free_path(path);
6362 * drop subtree rooted at tree block 'node'.
6364 * NOTE: this function will unlock and release tree block 'node'
6366 int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
6367 struct btrfs_root *root,
6368 struct extent_buffer *node,
6369 struct extent_buffer *parent)
6371 struct btrfs_path *path;
6372 struct walk_control *wc;
6378 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
6380 path = btrfs_alloc_path();
6383 wc = kzalloc(sizeof(*wc), GFP_NOFS);
6386 btrfs_assert_tree_locked(parent);
6387 parent_level = btrfs_header_level(parent);
6388 extent_buffer_get(parent);
6389 path->nodes[parent_level] = parent;
6390 path->slots[parent_level] = btrfs_header_nritems(parent);
6392 btrfs_assert_tree_locked(node);
6393 level = btrfs_header_level(node);
6394 path->nodes[level] = node;
6395 path->slots[level] = 0;
6396 path->locks[level] = 1;
6398 wc->refs[parent_level] = 1;
6399 wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF;
6401 wc->shared_level = -1;
6402 wc->stage = DROP_REFERENCE;
6405 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
6408 wret = walk_down_tree(trans, root, path, wc);
6414 wret = walk_up_tree(trans, root, path, wc, parent_level);
6422 btrfs_free_path(path);
6427 static unsigned long calc_ra(unsigned long start, unsigned long last,
6430 return min(last, start + nr - 1);
6433 static noinline int relocate_inode_pages(struct inode *inode, u64 start,
6438 unsigned long first_index;
6439 unsigned long last_index;
6442 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
6443 struct file_ra_state *ra;
6444 struct btrfs_ordered_extent *ordered;
6445 unsigned int total_read = 0;
6446 unsigned int total_dirty = 0;
6449 ra = kzalloc(sizeof(*ra), GFP_NOFS);
6451 mutex_lock(&inode->i_mutex);
6452 first_index = start >> PAGE_CACHE_SHIFT;
6453 last_index = (start + len - 1) >> PAGE_CACHE_SHIFT;
6455 /* make sure the dirty trick played by the caller work */
6456 ret = invalidate_inode_pages2_range(inode->i_mapping,
6457 first_index, last_index);
6461 file_ra_state_init(ra, inode->i_mapping);
6463 for (i = first_index ; i <= last_index; i++) {
6464 if (total_read % ra->ra_pages == 0) {
6465 btrfs_force_ra(inode->i_mapping, ra, NULL, i,
6466 calc_ra(i, last_index, ra->ra_pages));
6470 if (((u64)i << PAGE_CACHE_SHIFT) > i_size_read(inode))
6472 page = grab_cache_page(inode->i_mapping, i);
6477 if (!PageUptodate(page)) {
6478 btrfs_readpage(NULL, page);
6480 if (!PageUptodate(page)) {
6482 page_cache_release(page);
6487 wait_on_page_writeback(page);
6489 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
6490 page_end = page_start + PAGE_CACHE_SIZE - 1;
6491 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
6493 ordered = btrfs_lookup_ordered_extent(inode, page_start);
6495 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
6497 page_cache_release(page);
6498 btrfs_start_ordered_extent(inode, ordered, 1);
6499 btrfs_put_ordered_extent(ordered);
6502 set_page_extent_mapped(page);
6504 if (i == first_index)
6505 set_extent_bits(io_tree, page_start, page_end,
6506 EXTENT_BOUNDARY, GFP_NOFS);
6507 btrfs_set_extent_delalloc(inode, page_start, page_end);
6509 set_page_dirty(page);
6512 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
6514 page_cache_release(page);
6519 mutex_unlock(&inode->i_mutex);
6520 balance_dirty_pages_ratelimited_nr(inode->i_mapping, total_dirty);
6524 static noinline int relocate_data_extent(struct inode *reloc_inode,
6525 struct btrfs_key *extent_key,
6528 struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
6529 struct extent_map_tree *em_tree = &BTRFS_I(reloc_inode)->extent_tree;
6530 struct extent_map *em;
6531 u64 start = extent_key->objectid - offset;
6532 u64 end = start + extent_key->offset - 1;
6534 em = alloc_extent_map(GFP_NOFS);
6535 BUG_ON(!em || IS_ERR(em));
6538 em->len = extent_key->offset;
6539 em->block_len = extent_key->offset;
6540 em->block_start = extent_key->objectid;
6541 em->bdev = root->fs_info->fs_devices->latest_bdev;
6542 set_bit(EXTENT_FLAG_PINNED, &em->flags);
6544 /* setup extent map to cheat btrfs_readpage */
6545 lock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
6548 write_lock(&em_tree->lock);
6549 ret = add_extent_mapping(em_tree, em);
6550 write_unlock(&em_tree->lock);
6551 if (ret != -EEXIST) {
6552 free_extent_map(em);
6555 btrfs_drop_extent_cache(reloc_inode, start, end, 0);
6557 unlock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
6559 return relocate_inode_pages(reloc_inode, start, extent_key->offset);
6562 struct btrfs_ref_path {
6564 u64 nodes[BTRFS_MAX_LEVEL];
6566 u64 root_generation;
6573 struct btrfs_key node_keys[BTRFS_MAX_LEVEL];
6574 u64 new_nodes[BTRFS_MAX_LEVEL];
6577 struct disk_extent {
6588 static int is_cowonly_root(u64 root_objectid)
6590 if (root_objectid == BTRFS_ROOT_TREE_OBJECTID ||
6591 root_objectid == BTRFS_EXTENT_TREE_OBJECTID ||
6592 root_objectid == BTRFS_CHUNK_TREE_OBJECTID ||
6593 root_objectid == BTRFS_DEV_TREE_OBJECTID ||
6594 root_objectid == BTRFS_TREE_LOG_OBJECTID ||
6595 root_objectid == BTRFS_CSUM_TREE_OBJECTID)
6600 static noinline int __next_ref_path(struct btrfs_trans_handle *trans,
6601 struct btrfs_root *extent_root,
6602 struct btrfs_ref_path *ref_path,
6605 struct extent_buffer *leaf;
6606 struct btrfs_path *path;
6607 struct btrfs_extent_ref *ref;
6608 struct btrfs_key key;
6609 struct btrfs_key found_key;
6615 path = btrfs_alloc_path();
6620 ref_path->lowest_level = -1;
6621 ref_path->current_level = -1;
6622 ref_path->shared_level = -1;
6626 level = ref_path->current_level - 1;
6627 while (level >= -1) {
6629 if (level < ref_path->lowest_level)
6633 bytenr = ref_path->nodes[level];
6635 bytenr = ref_path->extent_start;
6636 BUG_ON(bytenr == 0);
6638 parent = ref_path->nodes[level + 1];
6639 ref_path->nodes[level + 1] = 0;
6640 ref_path->current_level = level;
6641 BUG_ON(parent == 0);
6643 key.objectid = bytenr;
6644 key.offset = parent + 1;
6645 key.type = BTRFS_EXTENT_REF_KEY;
6647 ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0);
6652 leaf = path->nodes[0];
6653 nritems = btrfs_header_nritems(leaf);
6654 if (path->slots[0] >= nritems) {
6655 ret = btrfs_next_leaf(extent_root, path);
6660 leaf = path->nodes[0];
6663 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6664 if (found_key.objectid == bytenr &&
6665 found_key.type == BTRFS_EXTENT_REF_KEY) {
6666 if (level < ref_path->shared_level)
6667 ref_path->shared_level = level;
6672 btrfs_release_path(extent_root, path);
6675 /* reached lowest level */
6679 level = ref_path->current_level;
6680 while (level < BTRFS_MAX_LEVEL - 1) {
6684 bytenr = ref_path->nodes[level];
6686 bytenr = ref_path->extent_start;
6688 BUG_ON(bytenr == 0);
6690 key.objectid = bytenr;
6692 key.type = BTRFS_EXTENT_REF_KEY;
6694 ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0);
6698 leaf = path->nodes[0];
6699 nritems = btrfs_header_nritems(leaf);
6700 if (path->slots[0] >= nritems) {
6701 ret = btrfs_next_leaf(extent_root, path);
6705 /* the extent was freed by someone */
6706 if (ref_path->lowest_level == level)
6708 btrfs_release_path(extent_root, path);
6711 leaf = path->nodes[0];
6714 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6715 if (found_key.objectid != bytenr ||
6716 found_key.type != BTRFS_EXTENT_REF_KEY) {
6717 /* the extent was freed by someone */
6718 if (ref_path->lowest_level == level) {
6722 btrfs_release_path(extent_root, path);
6726 ref = btrfs_item_ptr(leaf, path->slots[0],
6727 struct btrfs_extent_ref);
6728 ref_objectid = btrfs_ref_objectid(leaf, ref);
6729 if (ref_objectid < BTRFS_FIRST_FREE_OBJECTID) {
6731 level = (int)ref_objectid;
6732 BUG_ON(level >= BTRFS_MAX_LEVEL);
6733 ref_path->lowest_level = level;
6734 ref_path->current_level = level;
6735 ref_path->nodes[level] = bytenr;
6737 WARN_ON(ref_objectid != level);
6740 WARN_ON(level != -1);
6744 if (ref_path->lowest_level == level) {
6745 ref_path->owner_objectid = ref_objectid;
6746 ref_path->num_refs = btrfs_ref_num_refs(leaf, ref);
6750 * the block is tree root or the block isn't in reference
6753 if (found_key.objectid == found_key.offset ||
6754 is_cowonly_root(btrfs_ref_root(leaf, ref))) {
6755 ref_path->root_objectid = btrfs_ref_root(leaf, ref);
6756 ref_path->root_generation =
6757 btrfs_ref_generation(leaf, ref);
6759 /* special reference from the tree log */
6760 ref_path->nodes[0] = found_key.offset;
6761 ref_path->current_level = 0;
6768 BUG_ON(ref_path->nodes[level] != 0);
6769 ref_path->nodes[level] = found_key.offset;
6770 ref_path->current_level = level;
6773 * the reference was created in the running transaction,
6774 * no need to continue walking up.
6776 if (btrfs_ref_generation(leaf, ref) == trans->transid) {
6777 ref_path->root_objectid = btrfs_ref_root(leaf, ref);
6778 ref_path->root_generation =
6779 btrfs_ref_generation(leaf, ref);
6784 btrfs_release_path(extent_root, path);
6787 /* reached max tree level, but no tree root found. */
6790 btrfs_free_path(path);
6794 static int btrfs_first_ref_path(struct btrfs_trans_handle *trans,
6795 struct btrfs_root *extent_root,
6796 struct btrfs_ref_path *ref_path,
6799 memset(ref_path, 0, sizeof(*ref_path));
6800 ref_path->extent_start = extent_start;
6802 return __next_ref_path(trans, extent_root, ref_path, 1);
6805 static int btrfs_next_ref_path(struct btrfs_trans_handle *trans,
6806 struct btrfs_root *extent_root,
6807 struct btrfs_ref_path *ref_path)
6809 return __next_ref_path(trans, extent_root, ref_path, 0);
6812 static noinline int get_new_locations(struct inode *reloc_inode,
6813 struct btrfs_key *extent_key,
6814 u64 offset, int no_fragment,
6815 struct disk_extent **extents,
6818 struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
6819 struct btrfs_path *path;
6820 struct btrfs_file_extent_item *fi;
6821 struct extent_buffer *leaf;
6822 struct disk_extent *exts = *extents;
6823 struct btrfs_key found_key;
6828 int max = *nr_extents;
6831 WARN_ON(!no_fragment && *extents);
6834 exts = kmalloc(sizeof(*exts) * max, GFP_NOFS);
6839 path = btrfs_alloc_path();
6842 cur_pos = extent_key->objectid - offset;
6843 last_byte = extent_key->objectid + extent_key->offset;
6844 ret = btrfs_lookup_file_extent(NULL, root, path, reloc_inode->i_ino,
6854 leaf = path->nodes[0];
6855 nritems = btrfs_header_nritems(leaf);
6856 if (path->slots[0] >= nritems) {
6857 ret = btrfs_next_leaf(root, path);
6862 leaf = path->nodes[0];
6865 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6866 if (found_key.offset != cur_pos ||
6867 found_key.type != BTRFS_EXTENT_DATA_KEY ||
6868 found_key.objectid != reloc_inode->i_ino)
6871 fi = btrfs_item_ptr(leaf, path->slots[0],
6872 struct btrfs_file_extent_item);
6873 if (btrfs_file_extent_type(leaf, fi) !=
6874 BTRFS_FILE_EXTENT_REG ||
6875 btrfs_file_extent_disk_bytenr(leaf, fi) == 0)
6879 struct disk_extent *old = exts;
6881 exts = kzalloc(sizeof(*exts) * max, GFP_NOFS);
6882 memcpy(exts, old, sizeof(*exts) * nr);
6883 if (old != *extents)
6887 exts[nr].disk_bytenr =
6888 btrfs_file_extent_disk_bytenr(leaf, fi);
6889 exts[nr].disk_num_bytes =
6890 btrfs_file_extent_disk_num_bytes(leaf, fi);
6891 exts[nr].offset = btrfs_file_extent_offset(leaf, fi);
6892 exts[nr].num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
6893 exts[nr].ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
6894 exts[nr].compression = btrfs_file_extent_compression(leaf, fi);
6895 exts[nr].encryption = btrfs_file_extent_encryption(leaf, fi);
6896 exts[nr].other_encoding = btrfs_file_extent_other_encoding(leaf,
6898 BUG_ON(exts[nr].offset > 0);
6899 BUG_ON(exts[nr].compression || exts[nr].encryption);
6900 BUG_ON(exts[nr].num_bytes != exts[nr].disk_num_bytes);
6902 cur_pos += exts[nr].num_bytes;
6905 if (cur_pos + offset >= last_byte)
6915 BUG_ON(cur_pos + offset > last_byte);
6916 if (cur_pos + offset < last_byte) {
6922 btrfs_free_path(path);
6924 if (exts != *extents)
6933 static noinline int replace_one_extent(struct btrfs_trans_handle *trans,
6934 struct btrfs_root *root,
6935 struct btrfs_path *path,
6936 struct btrfs_key *extent_key,
6937 struct btrfs_key *leaf_key,
6938 struct btrfs_ref_path *ref_path,
6939 struct disk_extent *new_extents,
6942 struct extent_buffer *leaf;
6943 struct btrfs_file_extent_item *fi;
6944 struct inode *inode = NULL;
6945 struct btrfs_key key;
6950 u64 search_end = (u64)-1;
6953 int extent_locked = 0;
6957 memcpy(&key, leaf_key, sizeof(key));
6958 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) {
6959 if (key.objectid < ref_path->owner_objectid ||
6960 (key.objectid == ref_path->owner_objectid &&
6961 key.type < BTRFS_EXTENT_DATA_KEY)) {
6962 key.objectid = ref_path->owner_objectid;
6963 key.type = BTRFS_EXTENT_DATA_KEY;
6969 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
6973 leaf = path->nodes[0];
6974 nritems = btrfs_header_nritems(leaf);
6976 if (extent_locked && ret > 0) {
6978 * the file extent item was modified by someone
6979 * before the extent got locked.
6981 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
6982 lock_end, GFP_NOFS);
6986 if (path->slots[0] >= nritems) {
6987 if (++nr_scaned > 2)
6990 BUG_ON(extent_locked);
6991 ret = btrfs_next_leaf(root, path);
6996 leaf = path->nodes[0];
6997 nritems = btrfs_header_nritems(leaf);
7000 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
7002 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) {
7003 if ((key.objectid > ref_path->owner_objectid) ||
7004 (key.objectid == ref_path->owner_objectid &&
7005 key.type > BTRFS_EXTENT_DATA_KEY) ||
7006 key.offset >= search_end)
7010 if (inode && key.objectid != inode->i_ino) {
7011 BUG_ON(extent_locked);
7012 btrfs_release_path(root, path);
7013 mutex_unlock(&inode->i_mutex);
7019 if (key.type != BTRFS_EXTENT_DATA_KEY) {
7024 fi = btrfs_item_ptr(leaf, path->slots[0],
7025 struct btrfs_file_extent_item);
7026 extent_type = btrfs_file_extent_type(leaf, fi);
7027 if ((extent_type != BTRFS_FILE_EXTENT_REG &&
7028 extent_type != BTRFS_FILE_EXTENT_PREALLOC) ||
7029 (btrfs_file_extent_disk_bytenr(leaf, fi) !=
7030 extent_key->objectid)) {
7036 num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
7037 ext_offset = btrfs_file_extent_offset(leaf, fi);
7039 if (search_end == (u64)-1) {
7040 search_end = key.offset - ext_offset +
7041 btrfs_file_extent_ram_bytes(leaf, fi);
7044 if (!extent_locked) {
7045 lock_start = key.offset;
7046 lock_end = lock_start + num_bytes - 1;
7048 if (lock_start > key.offset ||
7049 lock_end + 1 < key.offset + num_bytes) {
7050 unlock_extent(&BTRFS_I(inode)->io_tree,
7051 lock_start, lock_end, GFP_NOFS);
7057 btrfs_release_path(root, path);
7059 inode = btrfs_iget_locked(root->fs_info->sb,
7060 key.objectid, root);
7061 if (inode->i_state & I_NEW) {
7062 BTRFS_I(inode)->root = root;
7063 BTRFS_I(inode)->location.objectid =
7065 BTRFS_I(inode)->location.type =
7066 BTRFS_INODE_ITEM_KEY;
7067 BTRFS_I(inode)->location.offset = 0;
7068 btrfs_read_locked_inode(inode);
7069 unlock_new_inode(inode);
7072 * some code call btrfs_commit_transaction while
7073 * holding the i_mutex, so we can't use mutex_lock
7076 if (is_bad_inode(inode) ||
7077 !mutex_trylock(&inode->i_mutex)) {
7080 key.offset = (u64)-1;
7085 if (!extent_locked) {
7086 struct btrfs_ordered_extent *ordered;
7088 btrfs_release_path(root, path);
7090 lock_extent(&BTRFS_I(inode)->io_tree, lock_start,
7091 lock_end, GFP_NOFS);
7092 ordered = btrfs_lookup_first_ordered_extent(inode,
7095 ordered->file_offset <= lock_end &&
7096 ordered->file_offset + ordered->len > lock_start) {
7097 unlock_extent(&BTRFS_I(inode)->io_tree,
7098 lock_start, lock_end, GFP_NOFS);
7099 btrfs_start_ordered_extent(inode, ordered, 1);
7100 btrfs_put_ordered_extent(ordered);
7101 key.offset += num_bytes;
7105 btrfs_put_ordered_extent(ordered);
7111 if (nr_extents == 1) {
7112 /* update extent pointer in place */
7113 btrfs_set_file_extent_disk_bytenr(leaf, fi,
7114 new_extents[0].disk_bytenr);
7115 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
7116 new_extents[0].disk_num_bytes);
7117 btrfs_mark_buffer_dirty(leaf);
7119 btrfs_drop_extent_cache(inode, key.offset,
7120 key.offset + num_bytes - 1, 0);
7122 ret = btrfs_inc_extent_ref(trans, root,
7123 new_extents[0].disk_bytenr,
7124 new_extents[0].disk_num_bytes,
7126 root->root_key.objectid,
7131 ret = btrfs_free_extent(trans, root,
7132 extent_key->objectid,
7135 btrfs_header_owner(leaf),
7136 btrfs_header_generation(leaf),
7140 btrfs_release_path(root, path);
7141 key.offset += num_bytes;
7149 * drop old extent pointer at first, then insert the
7150 * new pointers one bye one
7152 btrfs_release_path(root, path);
7153 ret = btrfs_drop_extents(trans, root, inode, key.offset,
7154 key.offset + num_bytes,
7155 key.offset, &alloc_hint);
7158 for (i = 0; i < nr_extents; i++) {
7159 if (ext_offset >= new_extents[i].num_bytes) {
7160 ext_offset -= new_extents[i].num_bytes;
7163 extent_len = min(new_extents[i].num_bytes -
7164 ext_offset, num_bytes);
7166 ret = btrfs_insert_empty_item(trans, root,
7171 leaf = path->nodes[0];
7172 fi = btrfs_item_ptr(leaf, path->slots[0],
7173 struct btrfs_file_extent_item);
7174 btrfs_set_file_extent_generation(leaf, fi,
7176 btrfs_set_file_extent_type(leaf, fi,
7177 BTRFS_FILE_EXTENT_REG);
7178 btrfs_set_file_extent_disk_bytenr(leaf, fi,
7179 new_extents[i].disk_bytenr);
7180 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
7181 new_extents[i].disk_num_bytes);
7182 btrfs_set_file_extent_ram_bytes(leaf, fi,
7183 new_extents[i].ram_bytes);
7185 btrfs_set_file_extent_compression(leaf, fi,
7186 new_extents[i].compression);
7187 btrfs_set_file_extent_encryption(leaf, fi,
7188 new_extents[i].encryption);
7189 btrfs_set_file_extent_other_encoding(leaf, fi,
7190 new_extents[i].other_encoding);
7192 btrfs_set_file_extent_num_bytes(leaf, fi,
7194 ext_offset += new_extents[i].offset;
7195 btrfs_set_file_extent_offset(leaf, fi,
7197 btrfs_mark_buffer_dirty(leaf);
7199 btrfs_drop_extent_cache(inode, key.offset,
7200 key.offset + extent_len - 1, 0);
7202 ret = btrfs_inc_extent_ref(trans, root,
7203 new_extents[i].disk_bytenr,
7204 new_extents[i].disk_num_bytes,
7206 root->root_key.objectid,
7207 trans->transid, key.objectid);
7209 btrfs_release_path(root, path);
7211 inode_add_bytes(inode, extent_len);
7214 num_bytes -= extent_len;
7215 key.offset += extent_len;
7220 BUG_ON(i >= nr_extents);
7224 if (extent_locked) {
7225 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
7226 lock_end, GFP_NOFS);
7230 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS &&
7231 key.offset >= search_end)
7238 btrfs_release_path(root, path);
7240 mutex_unlock(&inode->i_mutex);
7241 if (extent_locked) {
7242 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
7243 lock_end, GFP_NOFS);
7250 int btrfs_reloc_tree_cache_ref(struct btrfs_trans_handle *trans,
7251 struct btrfs_root *root,
7252 struct extent_buffer *buf, u64 orig_start)
7257 BUG_ON(btrfs_header_generation(buf) != trans->transid);
7258 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
7260 level = btrfs_header_level(buf);
7262 struct btrfs_leaf_ref *ref;
7263 struct btrfs_leaf_ref *orig_ref;
7265 orig_ref = btrfs_lookup_leaf_ref(root, orig_start);
7269 ref = btrfs_alloc_leaf_ref(root, orig_ref->nritems);
7271 btrfs_free_leaf_ref(root, orig_ref);
7275 ref->nritems = orig_ref->nritems;
7276 memcpy(ref->extents, orig_ref->extents,
7277 sizeof(ref->extents[0]) * ref->nritems);
7279 btrfs_free_leaf_ref(root, orig_ref);
7281 ref->root_gen = trans->transid;
7282 ref->bytenr = buf->start;
7283 ref->owner = btrfs_header_owner(buf);
7284 ref->generation = btrfs_header_generation(buf);
7286 ret = btrfs_add_leaf_ref(root, ref, 0);
7288 btrfs_free_leaf_ref(root, ref);
7293 static noinline int invalidate_extent_cache(struct btrfs_root *root,
7294 struct extent_buffer *leaf,
7295 struct btrfs_block_group_cache *group,
7296 struct btrfs_root *target_root)
7298 struct btrfs_key key;
7299 struct inode *inode = NULL;
7300 struct btrfs_file_extent_item *fi;
7301 struct extent_state *cached_state = NULL;
7303 u64 skip_objectid = 0;
7307 nritems = btrfs_header_nritems(leaf);
7308 for (i = 0; i < nritems; i++) {
7309 btrfs_item_key_to_cpu(leaf, &key, i);
7310 if (key.objectid == skip_objectid ||
7311 key.type != BTRFS_EXTENT_DATA_KEY)
7313 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
7314 if (btrfs_file_extent_type(leaf, fi) ==
7315 BTRFS_FILE_EXTENT_INLINE)
7317 if (btrfs_file_extent_disk_bytenr(leaf, fi) == 0)
7319 if (!inode || inode->i_ino != key.objectid) {
7321 inode = btrfs_ilookup(target_root->fs_info->sb,
7322 key.objectid, target_root, 1);
7325 skip_objectid = key.objectid;
7328 num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
7330 lock_extent_bits(&BTRFS_I(inode)->io_tree, key.offset,
7331 key.offset + num_bytes - 1, 0, &cached_state,
7333 btrfs_drop_extent_cache(inode, key.offset,
7334 key.offset + num_bytes - 1, 1);
7335 unlock_extent_cached(&BTRFS_I(inode)->io_tree, key.offset,
7336 key.offset + num_bytes - 1, &cached_state,
7344 static noinline int replace_extents_in_leaf(struct btrfs_trans_handle *trans,
7345 struct btrfs_root *root,
7346 struct extent_buffer *leaf,
7347 struct btrfs_block_group_cache *group,
7348 struct inode *reloc_inode)
7350 struct btrfs_key key;
7351 struct btrfs_key extent_key;
7352 struct btrfs_file_extent_item *fi;
7353 struct btrfs_leaf_ref *ref;
7354 struct disk_extent *new_extent;
7363 new_extent = kmalloc(sizeof(*new_extent), GFP_NOFS);
7364 BUG_ON(!new_extent);
7366 ref = btrfs_lookup_leaf_ref(root, leaf->start);
7370 nritems = btrfs_header_nritems(leaf);
7371 for (i = 0; i < nritems; i++) {
7372 btrfs_item_key_to_cpu(leaf, &key, i);
7373 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
7375 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
7376 if (btrfs_file_extent_type(leaf, fi) ==
7377 BTRFS_FILE_EXTENT_INLINE)
7379 bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
7380 num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
7385 if (bytenr >= group->key.objectid + group->key.offset ||
7386 bytenr + num_bytes <= group->key.objectid)
7389 extent_key.objectid = bytenr;
7390 extent_key.offset = num_bytes;
7391 extent_key.type = BTRFS_EXTENT_ITEM_KEY;
7393 ret = get_new_locations(reloc_inode, &extent_key,
7394 group->key.objectid, 1,
7395 &new_extent, &nr_extent);
7400 BUG_ON(ref->extents[ext_index].bytenr != bytenr);
7401 BUG_ON(ref->extents[ext_index].num_bytes != num_bytes);
7402 ref->extents[ext_index].bytenr = new_extent->disk_bytenr;
7403 ref->extents[ext_index].num_bytes = new_extent->disk_num_bytes;
7405 btrfs_set_file_extent_disk_bytenr(leaf, fi,
7406 new_extent->disk_bytenr);
7407 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
7408 new_extent->disk_num_bytes);
7409 btrfs_mark_buffer_dirty(leaf);
7411 ret = btrfs_inc_extent_ref(trans, root,
7412 new_extent->disk_bytenr,
7413 new_extent->disk_num_bytes,
7415 root->root_key.objectid,
7416 trans->transid, key.objectid);
7419 ret = btrfs_free_extent(trans, root,
7420 bytenr, num_bytes, leaf->start,
7421 btrfs_header_owner(leaf),
7422 btrfs_header_generation(leaf),
7428 BUG_ON(ext_index + 1 != ref->nritems);
7429 btrfs_free_leaf_ref(root, ref);
7433 int btrfs_free_reloc_root(struct btrfs_trans_handle *trans,
7434 struct btrfs_root *root)
7436 struct btrfs_root *reloc_root;
7439 if (root->reloc_root) {
7440 reloc_root = root->reloc_root;
7441 root->reloc_root = NULL;
7442 list_add(&reloc_root->dead_list,
7443 &root->fs_info->dead_reloc_roots);
7445 btrfs_set_root_bytenr(&reloc_root->root_item,
7446 reloc_root->node->start);
7447 btrfs_set_root_level(&root->root_item,
7448 btrfs_header_level(reloc_root->node));
7449 memset(&reloc_root->root_item.drop_progress, 0,
7450 sizeof(struct btrfs_disk_key));
7451 reloc_root->root_item.drop_level = 0;
7453 ret = btrfs_update_root(trans, root->fs_info->tree_root,
7454 &reloc_root->root_key,
7455 &reloc_root->root_item);
7461 int btrfs_drop_dead_reloc_roots(struct btrfs_root *root)
7463 struct btrfs_trans_handle *trans;
7464 struct btrfs_root *reloc_root;
7465 struct btrfs_root *prev_root = NULL;
7466 struct list_head dead_roots;
7470 INIT_LIST_HEAD(&dead_roots);
7471 list_splice_init(&root->fs_info->dead_reloc_roots, &dead_roots);
7473 while (!list_empty(&dead_roots)) {
7474 reloc_root = list_entry(dead_roots.prev,
7475 struct btrfs_root, dead_list);
7476 list_del_init(&reloc_root->dead_list);
7478 BUG_ON(reloc_root->commit_root != NULL);
7480 trans = btrfs_join_transaction(root, 1);
7483 mutex_lock(&root->fs_info->drop_mutex);
7484 ret = btrfs_drop_snapshot(trans, reloc_root);
7487 mutex_unlock(&root->fs_info->drop_mutex);
7489 nr = trans->blocks_used;
7490 ret = btrfs_end_transaction(trans, root);
7492 btrfs_btree_balance_dirty(root, nr);
7495 free_extent_buffer(reloc_root->node);
7497 ret = btrfs_del_root(trans, root->fs_info->tree_root,
7498 &reloc_root->root_key);
7500 mutex_unlock(&root->fs_info->drop_mutex);
7502 nr = trans->blocks_used;
7503 ret = btrfs_end_transaction(trans, root);
7505 btrfs_btree_balance_dirty(root, nr);
7508 prev_root = reloc_root;
7511 btrfs_remove_leaf_refs(prev_root, (u64)-1, 0);
7517 int btrfs_add_dead_reloc_root(struct btrfs_root *root)
7519 list_add(&root->dead_list, &root->fs_info->dead_reloc_roots);
7523 int btrfs_cleanup_reloc_trees(struct btrfs_root *root)
7525 struct btrfs_root *reloc_root;
7526 struct btrfs_trans_handle *trans;
7527 struct btrfs_key location;
7531 mutex_lock(&root->fs_info->tree_reloc_mutex);
7532 ret = btrfs_find_dead_roots(root, BTRFS_TREE_RELOC_OBJECTID, NULL);
7534 found = !list_empty(&root->fs_info->dead_reloc_roots);
7535 mutex_unlock(&root->fs_info->tree_reloc_mutex);
7538 trans = btrfs_start_transaction(root, 1);
7540 ret = btrfs_commit_transaction(trans, root);
7544 location.objectid = BTRFS_DATA_RELOC_TREE_OBJECTID;
7545 location.offset = (u64)-1;
7546 location.type = BTRFS_ROOT_ITEM_KEY;
7548 reloc_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
7549 BUG_ON(!reloc_root);
7550 btrfs_orphan_cleanup(reloc_root);
7554 static noinline int init_reloc_tree(struct btrfs_trans_handle *trans,
7555 struct btrfs_root *root)
7557 struct btrfs_root *reloc_root;
7558 struct extent_buffer *eb;
7559 struct btrfs_root_item *root_item;
7560 struct btrfs_key root_key;
7563 BUG_ON(!root->ref_cows);
7564 if (root->reloc_root)
7567 root_item = kmalloc(sizeof(*root_item), GFP_NOFS);
7570 ret = btrfs_copy_root(trans, root, root->commit_root,
7571 &eb, BTRFS_TREE_RELOC_OBJECTID);
7574 root_key.objectid = BTRFS_TREE_RELOC_OBJECTID;
7575 root_key.offset = root->root_key.objectid;
7576 root_key.type = BTRFS_ROOT_ITEM_KEY;
7578 memcpy(root_item, &root->root_item, sizeof(root_item));
7579 btrfs_set_root_refs(root_item, 0);
7580 btrfs_set_root_bytenr(root_item, eb->start);
7581 btrfs_set_root_level(root_item, btrfs_header_level(eb));
7582 btrfs_set_root_generation(root_item, trans->transid);
7584 btrfs_tree_unlock(eb);
7585 free_extent_buffer(eb);
7587 ret = btrfs_insert_root(trans, root->fs_info->tree_root,
7588 &root_key, root_item);
7592 reloc_root = btrfs_read_fs_root_no_radix(root->fs_info->tree_root,
7594 BUG_ON(!reloc_root);
7595 reloc_root->last_trans = trans->transid;
7596 reloc_root->commit_root = NULL;
7597 reloc_root->ref_tree = &root->fs_info->reloc_ref_tree;
7599 root->reloc_root = reloc_root;
7604 * Core function of space balance.
7606 * The idea is using reloc trees to relocate tree blocks in reference
7607 * counted roots. There is one reloc tree for each subvol, and all
7608 * reloc trees share same root key objectid. Reloc trees are snapshots
7609 * of the latest committed roots of subvols (root->commit_root).
7611 * To relocate a tree block referenced by a subvol, there are two steps.
7612 * COW the block through subvol's reloc tree, then update block pointer
7613 * in the subvol to point to the new block. Since all reloc trees share
7614 * same root key objectid, doing special handing for tree blocks owned
7615 * by them is easy. Once a tree block has been COWed in one reloc tree,
7616 * we can use the resulting new block directly when the same block is
7617 * required to COW again through other reloc trees. By this way, relocated
7618 * tree blocks are shared between reloc trees, so they are also shared
7621 static noinline int relocate_one_path(struct btrfs_trans_handle *trans,
7622 struct btrfs_root *root,
7623 struct btrfs_path *path,
7624 struct btrfs_key *first_key,
7625 struct btrfs_ref_path *ref_path,
7626 struct btrfs_block_group_cache *group,
7627 struct inode *reloc_inode)
7629 struct btrfs_root *reloc_root;
7630 struct extent_buffer *eb = NULL;
7631 struct btrfs_key *keys;
7635 int lowest_level = 0;
7638 if (ref_path->owner_objectid < BTRFS_FIRST_FREE_OBJECTID)
7639 lowest_level = ref_path->owner_objectid;
7641 if (!root->ref_cows) {
7642 path->lowest_level = lowest_level;
7643 ret = btrfs_search_slot(trans, root, first_key, path, 0, 1);
7645 path->lowest_level = 0;
7646 btrfs_release_path(root, path);
7650 mutex_lock(&root->fs_info->tree_reloc_mutex);
7651 ret = init_reloc_tree(trans, root);
7653 reloc_root = root->reloc_root;
7655 shared_level = ref_path->shared_level;
7656 ref_path->shared_level = BTRFS_MAX_LEVEL - 1;
7658 keys = ref_path->node_keys;
7659 nodes = ref_path->new_nodes;
7660 memset(&keys[shared_level + 1], 0,
7661 sizeof(*keys) * (BTRFS_MAX_LEVEL - shared_level - 1));
7662 memset(&nodes[shared_level + 1], 0,
7663 sizeof(*nodes) * (BTRFS_MAX_LEVEL - shared_level - 1));
7665 if (nodes[lowest_level] == 0) {
7666 path->lowest_level = lowest_level;
7667 ret = btrfs_search_slot(trans, reloc_root, first_key, path,
7670 for (level = lowest_level; level < BTRFS_MAX_LEVEL; level++) {
7671 eb = path->nodes[level];
7672 if (!eb || eb == reloc_root->node)
7674 nodes[level] = eb->start;
7676 btrfs_item_key_to_cpu(eb, &keys[level], 0);
7678 btrfs_node_key_to_cpu(eb, &keys[level], 0);
7681 ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7682 eb = path->nodes[0];
7683 ret = replace_extents_in_leaf(trans, reloc_root, eb,
7684 group, reloc_inode);
7687 btrfs_release_path(reloc_root, path);
7689 ret = btrfs_merge_path(trans, reloc_root, keys, nodes,
7695 * replace tree blocks in the fs tree with tree blocks in
7698 ret = btrfs_merge_path(trans, root, keys, nodes, lowest_level);
7701 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7702 ret = btrfs_search_slot(trans, reloc_root, first_key, path,
7705 extent_buffer_get(path->nodes[0]);
7706 eb = path->nodes[0];
7707 btrfs_release_path(reloc_root, path);
7708 ret = invalidate_extent_cache(reloc_root, eb, group, root);
7710 free_extent_buffer(eb);
7713 mutex_unlock(&root->fs_info->tree_reloc_mutex);
7714 path->lowest_level = 0;
7718 static noinline int relocate_tree_block(struct btrfs_trans_handle *trans,
7719 struct btrfs_root *root,
7720 struct btrfs_path *path,
7721 struct btrfs_key *first_key,
7722 struct btrfs_ref_path *ref_path)
7726 ret = relocate_one_path(trans, root, path, first_key,
7727 ref_path, NULL, NULL);
7733 static noinline int del_extent_zero(struct btrfs_trans_handle *trans,
7734 struct btrfs_root *extent_root,
7735 struct btrfs_path *path,
7736 struct btrfs_key *extent_key)
7740 ret = btrfs_search_slot(trans, extent_root, extent_key, path, -1, 1);
7743 ret = btrfs_del_item(trans, extent_root, path);
7745 btrfs_release_path(extent_root, path);
7749 static noinline struct btrfs_root *read_ref_root(struct btrfs_fs_info *fs_info,
7750 struct btrfs_ref_path *ref_path)
7752 struct btrfs_key root_key;
7754 root_key.objectid = ref_path->root_objectid;
7755 root_key.type = BTRFS_ROOT_ITEM_KEY;
7756 if (is_cowonly_root(ref_path->root_objectid))
7757 root_key.offset = 0;
7759 root_key.offset = (u64)-1;
7761 return btrfs_read_fs_root_no_name(fs_info, &root_key);
7764 static noinline int relocate_one_extent(struct btrfs_root *extent_root,
7765 struct btrfs_path *path,
7766 struct btrfs_key *extent_key,
7767 struct btrfs_block_group_cache *group,
7768 struct inode *reloc_inode, int pass)
7770 struct btrfs_trans_handle *trans;
7771 struct btrfs_root *found_root;
7772 struct btrfs_ref_path *ref_path = NULL;
7773 struct disk_extent *new_extents = NULL;
7778 struct btrfs_key first_key;
7782 trans = btrfs_start_transaction(extent_root, 1);
7785 if (extent_key->objectid == 0) {
7786 ret = del_extent_zero(trans, extent_root, path, extent_key);
7790 ref_path = kmalloc(sizeof(*ref_path), GFP_NOFS);
7796 for (loops = 0; ; loops++) {
7798 ret = btrfs_first_ref_path(trans, extent_root, ref_path,
7799 extent_key->objectid);
7801 ret = btrfs_next_ref_path(trans, extent_root, ref_path);
7808 if (ref_path->root_objectid == BTRFS_TREE_LOG_OBJECTID ||
7809 ref_path->root_objectid == BTRFS_TREE_RELOC_OBJECTID)
7812 found_root = read_ref_root(extent_root->fs_info, ref_path);
7813 BUG_ON(!found_root);
7815 * for reference counted tree, only process reference paths
7816 * rooted at the latest committed root.
7818 if (found_root->ref_cows &&
7819 ref_path->root_generation != found_root->root_key.offset)
7822 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7825 * copy data extents to new locations
7827 u64 group_start = group->key.objectid;
7828 ret = relocate_data_extent(reloc_inode,
7837 level = ref_path->owner_objectid;
7840 if (prev_block != ref_path->nodes[level]) {
7841 struct extent_buffer *eb;
7842 u64 block_start = ref_path->nodes[level];
7843 u64 block_size = btrfs_level_size(found_root, level);
7845 eb = read_tree_block(found_root, block_start,
7847 btrfs_tree_lock(eb);
7848 BUG_ON(level != btrfs_header_level(eb));
7851 btrfs_item_key_to_cpu(eb, &first_key, 0);
7853 btrfs_node_key_to_cpu(eb, &first_key, 0);
7855 btrfs_tree_unlock(eb);
7856 free_extent_buffer(eb);
7857 prev_block = block_start;
7860 mutex_lock(&extent_root->fs_info->trans_mutex);
7861 btrfs_record_root_in_trans(found_root);
7862 mutex_unlock(&extent_root->fs_info->trans_mutex);
7863 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7865 * try to update data extent references while
7866 * keeping metadata shared between snapshots.
7869 ret = relocate_one_path(trans, found_root,
7870 path, &first_key, ref_path,
7871 group, reloc_inode);
7877 * use fallback method to process the remaining
7881 u64 group_start = group->key.objectid;
7882 new_extents = kmalloc(sizeof(*new_extents),
7885 ret = get_new_locations(reloc_inode,
7893 ret = replace_one_extent(trans, found_root,
7895 &first_key, ref_path,
7896 new_extents, nr_extents);
7898 ret = relocate_tree_block(trans, found_root, path,
7899 &first_key, ref_path);
7906 btrfs_end_transaction(trans, extent_root);
7913 static u64 update_block_group_flags(struct btrfs_root *root, u64 flags)
7916 u64 stripped = BTRFS_BLOCK_GROUP_RAID0 |
7917 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
7920 * we add in the count of missing devices because we want
7921 * to make sure that any RAID levels on a degraded FS
7922 * continue to be honored.
7924 num_devices = root->fs_info->fs_devices->rw_devices +
7925 root->fs_info->fs_devices->missing_devices;
7927 if (num_devices == 1) {
7928 stripped |= BTRFS_BLOCK_GROUP_DUP;
7929 stripped = flags & ~stripped;
7931 /* turn raid0 into single device chunks */
7932 if (flags & BTRFS_BLOCK_GROUP_RAID0)
7935 /* turn mirroring into duplication */
7936 if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
7937 BTRFS_BLOCK_GROUP_RAID10))
7938 return stripped | BTRFS_BLOCK_GROUP_DUP;
7941 /* they already had raid on here, just return */
7942 if (flags & stripped)
7945 stripped |= BTRFS_BLOCK_GROUP_DUP;
7946 stripped = flags & ~stripped;
7948 /* switch duplicated blocks with raid1 */
7949 if (flags & BTRFS_BLOCK_GROUP_DUP)
7950 return stripped | BTRFS_BLOCK_GROUP_RAID1;
7952 /* turn single device chunks into raid0 */
7953 return stripped | BTRFS_BLOCK_GROUP_RAID0;
7958 static int set_block_group_ro(struct btrfs_block_group_cache *cache)
7960 struct btrfs_space_info *sinfo = cache->space_info;
7967 spin_lock(&sinfo->lock);
7968 spin_lock(&cache->lock);
7969 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
7970 cache->bytes_super - btrfs_block_group_used(&cache->item);
7972 if (sinfo->bytes_used + sinfo->bytes_reserved + sinfo->bytes_pinned +
7973 sinfo->bytes_may_use + sinfo->bytes_readonly +
7974 cache->reserved_pinned + num_bytes <= sinfo->total_bytes) {
7975 sinfo->bytes_readonly += num_bytes;
7976 sinfo->bytes_reserved += cache->reserved_pinned;
7977 cache->reserved_pinned = 0;
7982 spin_unlock(&cache->lock);
7983 spin_unlock(&sinfo->lock);
7987 int btrfs_set_block_group_ro(struct btrfs_root *root,
7988 struct btrfs_block_group_cache *cache)
7991 struct btrfs_trans_handle *trans;
7997 trans = btrfs_join_transaction(root, 1);
7998 BUG_ON(IS_ERR(trans));
8000 alloc_flags = update_block_group_flags(root, cache->flags);
8001 if (alloc_flags != cache->flags)
8002 do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags, 1);
8004 ret = set_block_group_ro(cache);
8007 alloc_flags = get_alloc_profile(root, cache->space_info->flags);
8008 ret = do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags, 1);
8011 ret = set_block_group_ro(cache);
8013 btrfs_end_transaction(trans, root);
8018 * helper to account the unused space of all the readonly block group in the
8019 * list. takes mirrors into account.
8021 static u64 __btrfs_get_ro_block_group_free_space(struct list_head *groups_list)
8023 struct btrfs_block_group_cache *block_group;
8027 list_for_each_entry(block_group, groups_list, list) {
8028 spin_lock(&block_group->lock);
8030 if (!block_group->ro) {
8031 spin_unlock(&block_group->lock);
8035 if (block_group->flags & (BTRFS_BLOCK_GROUP_RAID1 |
8036 BTRFS_BLOCK_GROUP_RAID10 |
8037 BTRFS_BLOCK_GROUP_DUP))
8042 free_bytes += (block_group->key.offset -
8043 btrfs_block_group_used(&block_group->item)) *
8046 spin_unlock(&block_group->lock);
8053 * helper to account the unused space of all the readonly block group in the
8054 * space_info. takes mirrors into account.
8056 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo)
8061 spin_lock(&sinfo->lock);
8063 for(i = 0; i < BTRFS_NR_RAID_TYPES; i++)
8064 if (!list_empty(&sinfo->block_groups[i]))
8065 free_bytes += __btrfs_get_ro_block_group_free_space(
8066 &sinfo->block_groups[i]);
8068 spin_unlock(&sinfo->lock);
8073 int btrfs_set_block_group_rw(struct btrfs_root *root,
8074 struct btrfs_block_group_cache *cache)
8076 struct btrfs_space_info *sinfo = cache->space_info;
8081 spin_lock(&sinfo->lock);
8082 spin_lock(&cache->lock);
8083 num_bytes = cache->key.offset - cache->reserved - cache->pinned -
8084 cache->bytes_super - btrfs_block_group_used(&cache->item);
8085 sinfo->bytes_readonly -= num_bytes;
8087 spin_unlock(&cache->lock);
8088 spin_unlock(&sinfo->lock);
8093 * checks to see if its even possible to relocate this block group.
8095 * @return - -1 if it's not a good idea to relocate this block group, 0 if its
8096 * ok to go ahead and try.
8098 int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
8100 struct btrfs_block_group_cache *block_group;
8101 struct btrfs_space_info *space_info;
8102 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
8103 struct btrfs_device *device;
8107 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
8109 /* odd, couldn't find the block group, leave it alone */
8113 /* no bytes used, we're good */
8114 if (!btrfs_block_group_used(&block_group->item))
8117 space_info = block_group->space_info;
8118 spin_lock(&space_info->lock);
8120 full = space_info->full;
8123 * if this is the last block group we have in this space, we can't
8124 * relocate it unless we're able to allocate a new chunk below.
8126 * Otherwise, we need to make sure we have room in the space to handle
8127 * all of the extents from this block group. If we can, we're good
8129 if ((space_info->total_bytes != block_group->key.offset) &&
8130 (space_info->bytes_used + space_info->bytes_reserved +
8131 space_info->bytes_pinned + space_info->bytes_readonly +
8132 btrfs_block_group_used(&block_group->item) <
8133 space_info->total_bytes)) {
8134 spin_unlock(&space_info->lock);
8137 spin_unlock(&space_info->lock);
8140 * ok we don't have enough space, but maybe we have free space on our
8141 * devices to allocate new chunks for relocation, so loop through our
8142 * alloc devices and guess if we have enough space. However, if we
8143 * were marked as full, then we know there aren't enough chunks, and we
8150 mutex_lock(&root->fs_info->chunk_mutex);
8151 list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
8152 u64 min_free = btrfs_block_group_used(&block_group->item);
8156 * check to make sure we can actually find a chunk with enough
8157 * space to fit our block group in.
8159 if (device->total_bytes > device->bytes_used + min_free) {
8160 ret = find_free_dev_extent(NULL, device, min_free,
8167 mutex_unlock(&root->fs_info->chunk_mutex);
8169 btrfs_put_block_group(block_group);
8173 static int find_first_block_group(struct btrfs_root *root,
8174 struct btrfs_path *path, struct btrfs_key *key)
8177 struct btrfs_key found_key;
8178 struct extent_buffer *leaf;
8181 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
8186 slot = path->slots[0];
8187 leaf = path->nodes[0];
8188 if (slot >= btrfs_header_nritems(leaf)) {
8189 ret = btrfs_next_leaf(root, path);
8196 btrfs_item_key_to_cpu(leaf, &found_key, slot);
8198 if (found_key.objectid >= key->objectid &&
8199 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
8209 void btrfs_put_block_group_cache(struct btrfs_fs_info *info)
8211 struct btrfs_block_group_cache *block_group;
8215 struct inode *inode;
8217 block_group = btrfs_lookup_first_block_group(info, last);
8218 while (block_group) {
8219 spin_lock(&block_group->lock);
8220 if (block_group->iref)
8222 spin_unlock(&block_group->lock);
8223 block_group = next_block_group(info->tree_root,
8233 inode = block_group->inode;
8234 block_group->iref = 0;
8235 block_group->inode = NULL;
8236 spin_unlock(&block_group->lock);
8238 last = block_group->key.objectid + block_group->key.offset;
8239 btrfs_put_block_group(block_group);
8243 int btrfs_free_block_groups(struct btrfs_fs_info *info)
8245 struct btrfs_block_group_cache *block_group;
8246 struct btrfs_space_info *space_info;
8247 struct btrfs_caching_control *caching_ctl;
8250 down_write(&info->extent_commit_sem);
8251 while (!list_empty(&info->caching_block_groups)) {
8252 caching_ctl = list_entry(info->caching_block_groups.next,
8253 struct btrfs_caching_control, list);
8254 list_del(&caching_ctl->list);
8255 put_caching_control(caching_ctl);
8257 up_write(&info->extent_commit_sem);
8259 spin_lock(&info->block_group_cache_lock);
8260 while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
8261 block_group = rb_entry(n, struct btrfs_block_group_cache,
8263 rb_erase(&block_group->cache_node,
8264 &info->block_group_cache_tree);
8265 spin_unlock(&info->block_group_cache_lock);
8267 down_write(&block_group->space_info->groups_sem);
8268 list_del(&block_group->list);
8269 up_write(&block_group->space_info->groups_sem);
8271 if (block_group->cached == BTRFS_CACHE_STARTED)
8272 wait_block_group_cache_done(block_group);
8274 btrfs_remove_free_space_cache(block_group);
8275 btrfs_put_block_group(block_group);
8277 spin_lock(&info->block_group_cache_lock);
8279 spin_unlock(&info->block_group_cache_lock);
8281 /* now that all the block groups are freed, go through and
8282 * free all the space_info structs. This is only called during
8283 * the final stages of unmount, and so we know nobody is
8284 * using them. We call synchronize_rcu() once before we start,
8285 * just to be on the safe side.
8289 release_global_block_rsv(info);
8291 while(!list_empty(&info->space_info)) {
8292 space_info = list_entry(info->space_info.next,
8293 struct btrfs_space_info,
8295 if (space_info->bytes_pinned > 0 ||
8296 space_info->bytes_reserved > 0) {
8298 dump_space_info(space_info, 0, 0);
8300 list_del(&space_info->list);
8306 static void __link_block_group(struct btrfs_space_info *space_info,
8307 struct btrfs_block_group_cache *cache)
8309 int index = get_block_group_index(cache);
8311 down_write(&space_info->groups_sem);
8312 list_add_tail(&cache->list, &space_info->block_groups[index]);
8313 up_write(&space_info->groups_sem);
8316 int btrfs_read_block_groups(struct btrfs_root *root)
8318 struct btrfs_path *path;
8320 struct btrfs_block_group_cache *cache;
8321 struct btrfs_fs_info *info = root->fs_info;
8322 struct btrfs_space_info *space_info;
8323 struct btrfs_key key;
8324 struct btrfs_key found_key;
8325 struct extent_buffer *leaf;
8329 root = info->extent_root;
8332 btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
8333 path = btrfs_alloc_path();
8337 cache_gen = btrfs_super_cache_generation(&root->fs_info->super_copy);
8338 if (cache_gen != 0 &&
8339 btrfs_super_generation(&root->fs_info->super_copy) != cache_gen)
8341 if (btrfs_test_opt(root, CLEAR_CACHE))
8343 if (!btrfs_test_opt(root, SPACE_CACHE) && cache_gen)
8344 printk(KERN_INFO "btrfs: disk space caching is enabled\n");
8347 ret = find_first_block_group(root, path, &key);
8352 leaf = path->nodes[0];
8353 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
8354 cache = kzalloc(sizeof(*cache), GFP_NOFS);
8360 atomic_set(&cache->count, 1);
8361 spin_lock_init(&cache->lock);
8362 spin_lock_init(&cache->tree_lock);
8363 cache->fs_info = info;
8364 INIT_LIST_HEAD(&cache->list);
8365 INIT_LIST_HEAD(&cache->cluster_list);
8368 cache->disk_cache_state = BTRFS_DC_CLEAR;
8371 * we only want to have 32k of ram per block group for keeping
8372 * track of free space, and if we pass 1/2 of that we want to
8373 * start converting things over to using bitmaps
8375 cache->extents_thresh = ((1024 * 32) / 2) /
8376 sizeof(struct btrfs_free_space);
8378 read_extent_buffer(leaf, &cache->item,
8379 btrfs_item_ptr_offset(leaf, path->slots[0]),
8380 sizeof(cache->item));
8381 memcpy(&cache->key, &found_key, sizeof(found_key));
8383 key.objectid = found_key.objectid + found_key.offset;
8384 btrfs_release_path(root, path);
8385 cache->flags = btrfs_block_group_flags(&cache->item);
8386 cache->sectorsize = root->sectorsize;
8389 * check for two cases, either we are full, and therefore
8390 * don't need to bother with the caching work since we won't
8391 * find any space, or we are empty, and we can just add all
8392 * the space in and be done with it. This saves us _alot_ of
8393 * time, particularly in the full case.
8395 if (found_key.offset == btrfs_block_group_used(&cache->item)) {
8396 exclude_super_stripes(root, cache);
8397 cache->last_byte_to_unpin = (u64)-1;
8398 cache->cached = BTRFS_CACHE_FINISHED;
8399 free_excluded_extents(root, cache);
8400 } else if (btrfs_block_group_used(&cache->item) == 0) {
8401 exclude_super_stripes(root, cache);
8402 cache->last_byte_to_unpin = (u64)-1;
8403 cache->cached = BTRFS_CACHE_FINISHED;
8404 add_new_free_space(cache, root->fs_info,
8406 found_key.objectid +
8408 free_excluded_extents(root, cache);
8411 ret = update_space_info(info, cache->flags, found_key.offset,
8412 btrfs_block_group_used(&cache->item),
8415 cache->space_info = space_info;
8416 spin_lock(&cache->space_info->lock);
8417 cache->space_info->bytes_readonly += cache->bytes_super;
8418 spin_unlock(&cache->space_info->lock);
8420 __link_block_group(space_info, cache);
8422 ret = btrfs_add_block_group_cache(root->fs_info, cache);
8425 set_avail_alloc_bits(root->fs_info, cache->flags);
8426 if (btrfs_chunk_readonly(root, cache->key.objectid))
8427 set_block_group_ro(cache);
8430 list_for_each_entry_rcu(space_info, &root->fs_info->space_info, list) {
8431 if (!(get_alloc_profile(root, space_info->flags) &
8432 (BTRFS_BLOCK_GROUP_RAID10 |
8433 BTRFS_BLOCK_GROUP_RAID1 |
8434 BTRFS_BLOCK_GROUP_DUP)))
8437 * avoid allocating from un-mirrored block group if there are
8438 * mirrored block groups.
8440 list_for_each_entry(cache, &space_info->block_groups[3], list)
8441 set_block_group_ro(cache);
8442 list_for_each_entry(cache, &space_info->block_groups[4], list)
8443 set_block_group_ro(cache);
8446 init_global_block_rsv(info);
8449 btrfs_free_path(path);
8453 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
8454 struct btrfs_root *root, u64 bytes_used,
8455 u64 type, u64 chunk_objectid, u64 chunk_offset,
8459 struct btrfs_root *extent_root;
8460 struct btrfs_block_group_cache *cache;
8462 extent_root = root->fs_info->extent_root;
8464 root->fs_info->last_trans_log_full_commit = trans->transid;
8466 cache = kzalloc(sizeof(*cache), GFP_NOFS);
8470 cache->key.objectid = chunk_offset;
8471 cache->key.offset = size;
8472 cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
8473 cache->sectorsize = root->sectorsize;
8474 cache->fs_info = root->fs_info;
8477 * we only want to have 32k of ram per block group for keeping track
8478 * of free space, and if we pass 1/2 of that we want to start
8479 * converting things over to using bitmaps
8481 cache->extents_thresh = ((1024 * 32) / 2) /
8482 sizeof(struct btrfs_free_space);
8483 atomic_set(&cache->count, 1);
8484 spin_lock_init(&cache->lock);
8485 spin_lock_init(&cache->tree_lock);
8486 INIT_LIST_HEAD(&cache->list);
8487 INIT_LIST_HEAD(&cache->cluster_list);
8489 btrfs_set_block_group_used(&cache->item, bytes_used);
8490 btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
8491 cache->flags = type;
8492 btrfs_set_block_group_flags(&cache->item, type);
8494 cache->last_byte_to_unpin = (u64)-1;
8495 cache->cached = BTRFS_CACHE_FINISHED;
8496 exclude_super_stripes(root, cache);
8498 add_new_free_space(cache, root->fs_info, chunk_offset,
8499 chunk_offset + size);
8501 free_excluded_extents(root, cache);
8503 ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
8504 &cache->space_info);
8507 spin_lock(&cache->space_info->lock);
8508 cache->space_info->bytes_readonly += cache->bytes_super;
8509 spin_unlock(&cache->space_info->lock);
8511 __link_block_group(cache->space_info, cache);
8513 ret = btrfs_add_block_group_cache(root->fs_info, cache);
8516 ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
8517 sizeof(cache->item));
8520 set_avail_alloc_bits(extent_root->fs_info, type);
8525 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
8526 struct btrfs_root *root, u64 group_start)
8528 struct btrfs_path *path;
8529 struct btrfs_block_group_cache *block_group;
8530 struct btrfs_free_cluster *cluster;
8531 struct btrfs_root *tree_root = root->fs_info->tree_root;
8532 struct btrfs_key key;
8533 struct inode *inode;
8537 root = root->fs_info->extent_root;
8539 block_group = btrfs_lookup_block_group(root->fs_info, group_start);
8540 BUG_ON(!block_group);
8541 BUG_ON(!block_group->ro);
8543 memcpy(&key, &block_group->key, sizeof(key));
8544 if (block_group->flags & (BTRFS_BLOCK_GROUP_DUP |
8545 BTRFS_BLOCK_GROUP_RAID1 |
8546 BTRFS_BLOCK_GROUP_RAID10))
8551 /* make sure this block group isn't part of an allocation cluster */
8552 cluster = &root->fs_info->data_alloc_cluster;
8553 spin_lock(&cluster->refill_lock);
8554 btrfs_return_cluster_to_free_space(block_group, cluster);
8555 spin_unlock(&cluster->refill_lock);
8558 * make sure this block group isn't part of a metadata
8559 * allocation cluster
8561 cluster = &root->fs_info->meta_alloc_cluster;
8562 spin_lock(&cluster->refill_lock);
8563 btrfs_return_cluster_to_free_space(block_group, cluster);
8564 spin_unlock(&cluster->refill_lock);
8566 path = btrfs_alloc_path();
8569 inode = lookup_free_space_inode(root, block_group, path);
8570 if (!IS_ERR(inode)) {
8571 btrfs_orphan_add(trans, inode);
8573 /* One for the block groups ref */
8574 spin_lock(&block_group->lock);
8575 if (block_group->iref) {
8576 block_group->iref = 0;
8577 block_group->inode = NULL;
8578 spin_unlock(&block_group->lock);
8581 spin_unlock(&block_group->lock);
8583 /* One for our lookup ref */
8587 key.objectid = BTRFS_FREE_SPACE_OBJECTID;
8588 key.offset = block_group->key.objectid;
8591 ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1);
8595 btrfs_release_path(tree_root, path);
8597 ret = btrfs_del_item(trans, tree_root, path);
8600 btrfs_release_path(tree_root, path);
8603 spin_lock(&root->fs_info->block_group_cache_lock);
8604 rb_erase(&block_group->cache_node,
8605 &root->fs_info->block_group_cache_tree);
8606 spin_unlock(&root->fs_info->block_group_cache_lock);
8608 down_write(&block_group->space_info->groups_sem);
8610 * we must use list_del_init so people can check to see if they
8611 * are still on the list after taking the semaphore
8613 list_del_init(&block_group->list);
8614 up_write(&block_group->space_info->groups_sem);
8616 if (block_group->cached == BTRFS_CACHE_STARTED)
8617 wait_block_group_cache_done(block_group);
8619 btrfs_remove_free_space_cache(block_group);
8621 spin_lock(&block_group->space_info->lock);
8622 block_group->space_info->total_bytes -= block_group->key.offset;
8623 block_group->space_info->bytes_readonly -= block_group->key.offset;
8624 block_group->space_info->disk_total -= block_group->key.offset * factor;
8625 spin_unlock(&block_group->space_info->lock);
8627 memcpy(&key, &block_group->key, sizeof(key));
8629 btrfs_clear_space_info_full(root->fs_info);
8631 btrfs_put_block_group(block_group);
8632 btrfs_put_block_group(block_group);
8634 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
8640 ret = btrfs_del_item(trans, root, path);
8642 btrfs_free_path(path);