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>
29 #include "print-tree.h"
30 #include "transaction.h"
33 #include "free-space-cache.h"
35 static int update_block_group(struct btrfs_trans_handle *trans,
36 struct btrfs_root *root,
37 u64 bytenr, u64 num_bytes, int alloc,
39 static int update_reserved_extents(struct btrfs_block_group_cache *cache,
40 u64 num_bytes, int reserve);
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 pin_down_bytes(struct btrfs_trans_handle *trans,
64 struct btrfs_root *root,
65 struct btrfs_path *path,
66 u64 bytenr, u64 num_bytes,
67 int is_data, int reserved,
68 struct extent_buffer **must_clean);
69 static int find_next_key(struct btrfs_path *path, int level,
70 struct btrfs_key *key);
71 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
72 int dump_block_groups);
75 block_group_cache_done(struct btrfs_block_group_cache *cache)
78 return cache->cached == BTRFS_CACHE_FINISHED;
81 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
83 return (cache->flags & bits) == bits;
87 * this adds the block group to the fs_info rb tree for the block group
90 static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
91 struct btrfs_block_group_cache *block_group)
94 struct rb_node *parent = NULL;
95 struct btrfs_block_group_cache *cache;
97 spin_lock(&info->block_group_cache_lock);
98 p = &info->block_group_cache_tree.rb_node;
102 cache = rb_entry(parent, struct btrfs_block_group_cache,
104 if (block_group->key.objectid < cache->key.objectid) {
106 } else if (block_group->key.objectid > cache->key.objectid) {
109 spin_unlock(&info->block_group_cache_lock);
114 rb_link_node(&block_group->cache_node, parent, p);
115 rb_insert_color(&block_group->cache_node,
116 &info->block_group_cache_tree);
117 spin_unlock(&info->block_group_cache_lock);
123 * This will return the block group at or after bytenr if contains is 0, else
124 * it will return the block group that contains the bytenr
126 static struct btrfs_block_group_cache *
127 block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
130 struct btrfs_block_group_cache *cache, *ret = NULL;
134 spin_lock(&info->block_group_cache_lock);
135 n = info->block_group_cache_tree.rb_node;
138 cache = rb_entry(n, struct btrfs_block_group_cache,
140 end = cache->key.objectid + cache->key.offset - 1;
141 start = cache->key.objectid;
143 if (bytenr < start) {
144 if (!contains && (!ret || start < ret->key.objectid))
147 } else if (bytenr > start) {
148 if (contains && bytenr <= end) {
159 atomic_inc(&ret->count);
160 spin_unlock(&info->block_group_cache_lock);
165 static int add_excluded_extent(struct btrfs_root *root,
166 u64 start, u64 num_bytes)
168 u64 end = start + num_bytes - 1;
169 set_extent_bits(&root->fs_info->freed_extents[0],
170 start, end, EXTENT_UPTODATE, GFP_NOFS);
171 set_extent_bits(&root->fs_info->freed_extents[1],
172 start, end, EXTENT_UPTODATE, GFP_NOFS);
176 static void free_excluded_extents(struct btrfs_root *root,
177 struct btrfs_block_group_cache *cache)
181 start = cache->key.objectid;
182 end = start + cache->key.offset - 1;
184 clear_extent_bits(&root->fs_info->freed_extents[0],
185 start, end, EXTENT_UPTODATE, GFP_NOFS);
186 clear_extent_bits(&root->fs_info->freed_extents[1],
187 start, end, EXTENT_UPTODATE, GFP_NOFS);
190 static int exclude_super_stripes(struct btrfs_root *root,
191 struct btrfs_block_group_cache *cache)
198 if (cache->key.objectid < BTRFS_SUPER_INFO_OFFSET) {
199 stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->key.objectid;
200 cache->bytes_super += stripe_len;
201 ret = add_excluded_extent(root, cache->key.objectid,
206 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
207 bytenr = btrfs_sb_offset(i);
208 ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
209 cache->key.objectid, bytenr,
210 0, &logical, &nr, &stripe_len);
214 cache->bytes_super += stripe_len;
215 ret = add_excluded_extent(root, logical[nr],
225 static struct btrfs_caching_control *
226 get_caching_control(struct btrfs_block_group_cache *cache)
228 struct btrfs_caching_control *ctl;
230 spin_lock(&cache->lock);
231 if (cache->cached != BTRFS_CACHE_STARTED) {
232 spin_unlock(&cache->lock);
236 ctl = cache->caching_ctl;
237 atomic_inc(&ctl->count);
238 spin_unlock(&cache->lock);
242 static void put_caching_control(struct btrfs_caching_control *ctl)
244 if (atomic_dec_and_test(&ctl->count))
249 * this is only called by cache_block_group, since we could have freed extents
250 * we need to check the pinned_extents for any extents that can't be used yet
251 * since their free space will be released as soon as the transaction commits.
253 static u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
254 struct btrfs_fs_info *info, u64 start, u64 end)
256 u64 extent_start, extent_end, size, total_added = 0;
259 while (start < end) {
260 ret = find_first_extent_bit(info->pinned_extents, start,
261 &extent_start, &extent_end,
262 EXTENT_DIRTY | EXTENT_UPTODATE);
266 if (extent_start <= start) {
267 start = extent_end + 1;
268 } else if (extent_start > start && extent_start < end) {
269 size = extent_start - start;
271 ret = btrfs_add_free_space(block_group, start,
274 start = extent_end + 1;
283 ret = btrfs_add_free_space(block_group, start, size);
290 static int caching_kthread(void *data)
292 struct btrfs_block_group_cache *block_group = data;
293 struct btrfs_fs_info *fs_info = block_group->fs_info;
294 struct btrfs_caching_control *caching_ctl = block_group->caching_ctl;
295 struct btrfs_root *extent_root = fs_info->extent_root;
296 struct btrfs_path *path;
297 struct extent_buffer *leaf;
298 struct btrfs_key key;
304 path = btrfs_alloc_path();
308 exclude_super_stripes(extent_root, block_group);
309 spin_lock(&block_group->space_info->lock);
310 block_group->space_info->bytes_super += block_group->bytes_super;
311 spin_unlock(&block_group->space_info->lock);
313 last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
316 * We don't want to deadlock with somebody trying to allocate a new
317 * extent for the extent root while also trying to search the extent
318 * root to add free space. So we skip locking and search the commit
319 * root, since its read-only
321 path->skip_locking = 1;
322 path->search_commit_root = 1;
327 key.type = BTRFS_EXTENT_ITEM_KEY;
329 mutex_lock(&caching_ctl->mutex);
330 /* need to make sure the commit_root doesn't disappear */
331 down_read(&fs_info->extent_commit_sem);
333 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
337 leaf = path->nodes[0];
338 nritems = btrfs_header_nritems(leaf);
342 if (fs_info->closing > 1) {
347 if (path->slots[0] < nritems) {
348 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
350 ret = find_next_key(path, 0, &key);
354 caching_ctl->progress = last;
355 btrfs_release_path(extent_root, path);
356 up_read(&fs_info->extent_commit_sem);
357 mutex_unlock(&caching_ctl->mutex);
358 if (btrfs_transaction_in_commit(fs_info))
365 if (key.objectid < block_group->key.objectid) {
370 if (key.objectid >= block_group->key.objectid +
371 block_group->key.offset)
374 if (key.type == BTRFS_EXTENT_ITEM_KEY) {
375 total_found += add_new_free_space(block_group,
378 last = key.objectid + key.offset;
380 if (total_found > (1024 * 1024 * 2)) {
382 wake_up(&caching_ctl->wait);
389 total_found += add_new_free_space(block_group, fs_info, last,
390 block_group->key.objectid +
391 block_group->key.offset);
392 caching_ctl->progress = (u64)-1;
394 spin_lock(&block_group->lock);
395 block_group->caching_ctl = NULL;
396 block_group->cached = BTRFS_CACHE_FINISHED;
397 spin_unlock(&block_group->lock);
400 btrfs_free_path(path);
401 up_read(&fs_info->extent_commit_sem);
403 free_excluded_extents(extent_root, block_group);
405 mutex_unlock(&caching_ctl->mutex);
406 wake_up(&caching_ctl->wait);
408 put_caching_control(caching_ctl);
409 atomic_dec(&block_group->space_info->caching_threads);
413 static int cache_block_group(struct btrfs_block_group_cache *cache)
415 struct btrfs_fs_info *fs_info = cache->fs_info;
416 struct btrfs_caching_control *caching_ctl;
417 struct task_struct *tsk;
421 if (cache->cached != BTRFS_CACHE_NO)
424 caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_KERNEL);
425 BUG_ON(!caching_ctl);
427 INIT_LIST_HEAD(&caching_ctl->list);
428 mutex_init(&caching_ctl->mutex);
429 init_waitqueue_head(&caching_ctl->wait);
430 caching_ctl->block_group = cache;
431 caching_ctl->progress = cache->key.objectid;
432 /* one for caching kthread, one for caching block group list */
433 atomic_set(&caching_ctl->count, 2);
435 spin_lock(&cache->lock);
436 if (cache->cached != BTRFS_CACHE_NO) {
437 spin_unlock(&cache->lock);
441 cache->caching_ctl = caching_ctl;
442 cache->cached = BTRFS_CACHE_STARTED;
443 spin_unlock(&cache->lock);
445 down_write(&fs_info->extent_commit_sem);
446 list_add_tail(&caching_ctl->list, &fs_info->caching_block_groups);
447 up_write(&fs_info->extent_commit_sem);
449 atomic_inc(&cache->space_info->caching_threads);
451 tsk = kthread_run(caching_kthread, cache, "btrfs-cache-%llu\n",
452 cache->key.objectid);
455 printk(KERN_ERR "error running thread %d\n", ret);
463 * return the block group that starts at or after bytenr
465 static struct btrfs_block_group_cache *
466 btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr)
468 struct btrfs_block_group_cache *cache;
470 cache = block_group_cache_tree_search(info, bytenr, 0);
476 * return the block group that contains the given bytenr
478 struct btrfs_block_group_cache *btrfs_lookup_block_group(
479 struct btrfs_fs_info *info,
482 struct btrfs_block_group_cache *cache;
484 cache = block_group_cache_tree_search(info, bytenr, 1);
489 void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
491 if (atomic_dec_and_test(&cache->count))
495 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
498 struct list_head *head = &info->space_info;
499 struct btrfs_space_info *found;
502 list_for_each_entry_rcu(found, head, list) {
503 if (found->flags == flags) {
513 * after adding space to the filesystem, we need to clear the full flags
514 * on all the space infos.
516 void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
518 struct list_head *head = &info->space_info;
519 struct btrfs_space_info *found;
522 list_for_each_entry_rcu(found, head, list)
527 static u64 div_factor(u64 num, int factor)
536 u64 btrfs_find_block_group(struct btrfs_root *root,
537 u64 search_start, u64 search_hint, int owner)
539 struct btrfs_block_group_cache *cache;
541 u64 last = max(search_hint, search_start);
548 cache = btrfs_lookup_first_block_group(root->fs_info, last);
552 spin_lock(&cache->lock);
553 last = cache->key.objectid + cache->key.offset;
554 used = btrfs_block_group_used(&cache->item);
556 if ((full_search || !cache->ro) &&
557 block_group_bits(cache, BTRFS_BLOCK_GROUP_METADATA)) {
558 if (used + cache->pinned + cache->reserved <
559 div_factor(cache->key.offset, factor)) {
560 group_start = cache->key.objectid;
561 spin_unlock(&cache->lock);
562 btrfs_put_block_group(cache);
566 spin_unlock(&cache->lock);
567 btrfs_put_block_group(cache);
575 if (!full_search && factor < 10) {
585 /* simple helper to search for an existing extent at a given offset */
586 int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len)
589 struct btrfs_key key;
590 struct btrfs_path *path;
592 path = btrfs_alloc_path();
594 key.objectid = start;
596 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
597 ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path,
599 btrfs_free_path(path);
604 * Back reference rules. Back refs have three main goals:
606 * 1) differentiate between all holders of references to an extent so that
607 * when a reference is dropped we can make sure it was a valid reference
608 * before freeing the extent.
610 * 2) Provide enough information to quickly find the holders of an extent
611 * if we notice a given block is corrupted or bad.
613 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
614 * maintenance. This is actually the same as #2, but with a slightly
615 * different use case.
617 * There are two kinds of back refs. The implicit back refs is optimized
618 * for pointers in non-shared tree blocks. For a given pointer in a block,
619 * back refs of this kind provide information about the block's owner tree
620 * and the pointer's key. These information allow us to find the block by
621 * b-tree searching. The full back refs is for pointers in tree blocks not
622 * referenced by their owner trees. The location of tree block is recorded
623 * in the back refs. Actually the full back refs is generic, and can be
624 * used in all cases the implicit back refs is used. The major shortcoming
625 * of the full back refs is its overhead. Every time a tree block gets
626 * COWed, we have to update back refs entry for all pointers in it.
628 * For a newly allocated tree block, we use implicit back refs for
629 * pointers in it. This means most tree related operations only involve
630 * implicit back refs. For a tree block created in old transaction, the
631 * only way to drop a reference to it is COW it. So we can detect the
632 * event that tree block loses its owner tree's reference and do the
633 * back refs conversion.
635 * When a tree block is COW'd through a tree, there are four cases:
637 * The reference count of the block is one and the tree is the block's
638 * owner tree. Nothing to do in this case.
640 * The reference count of the block is one and the tree is not the
641 * block's owner tree. In this case, full back refs is used for pointers
642 * in the block. Remove these full back refs, add implicit back refs for
643 * every pointers in the new block.
645 * The reference count of the block is greater than one and the tree is
646 * the block's owner tree. In this case, implicit back refs is used for
647 * pointers in the block. Add full back refs for every pointers in the
648 * block, increase lower level extents' reference counts. The original
649 * implicit back refs are entailed to the new block.
651 * The reference count of the block is greater than one and the tree is
652 * not the block's owner tree. Add implicit back refs for every pointer in
653 * the new block, increase lower level extents' reference count.
655 * Back Reference Key composing:
657 * The key objectid corresponds to the first byte in the extent,
658 * The key type is used to differentiate between types of back refs.
659 * There are different meanings of the key offset for different types
662 * File extents can be referenced by:
664 * - multiple snapshots, subvolumes, or different generations in one subvol
665 * - different files inside a single subvolume
666 * - different offsets inside a file (bookend extents in file.c)
668 * The extent ref structure for the implicit back refs has fields for:
670 * - Objectid of the subvolume root
671 * - objectid of the file holding the reference
672 * - original offset in the file
673 * - how many bookend extents
675 * The key offset for the implicit back refs is hash of the first
678 * The extent ref structure for the full back refs has field for:
680 * - number of pointers in the tree leaf
682 * The key offset for the implicit back refs is the first byte of
685 * When a file extent is allocated, The implicit back refs is used.
686 * the fields are filled in:
688 * (root_key.objectid, inode objectid, offset in file, 1)
690 * When a file extent is removed file truncation, we find the
691 * corresponding implicit back refs and check the following fields:
693 * (btrfs_header_owner(leaf), inode objectid, offset in file)
695 * Btree extents can be referenced by:
697 * - Different subvolumes
699 * Both the implicit back refs and the full back refs for tree blocks
700 * only consist of key. The key offset for the implicit back refs is
701 * objectid of block's owner tree. The key offset for the full back refs
702 * is the first byte of parent block.
704 * When implicit back refs is used, information about the lowest key and
705 * level of the tree block are required. These information are stored in
706 * tree block info structure.
709 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
710 static int convert_extent_item_v0(struct btrfs_trans_handle *trans,
711 struct btrfs_root *root,
712 struct btrfs_path *path,
713 u64 owner, u32 extra_size)
715 struct btrfs_extent_item *item;
716 struct btrfs_extent_item_v0 *ei0;
717 struct btrfs_extent_ref_v0 *ref0;
718 struct btrfs_tree_block_info *bi;
719 struct extent_buffer *leaf;
720 struct btrfs_key key;
721 struct btrfs_key found_key;
722 u32 new_size = sizeof(*item);
726 leaf = path->nodes[0];
727 BUG_ON(btrfs_item_size_nr(leaf, path->slots[0]) != sizeof(*ei0));
729 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
730 ei0 = btrfs_item_ptr(leaf, path->slots[0],
731 struct btrfs_extent_item_v0);
732 refs = btrfs_extent_refs_v0(leaf, ei0);
734 if (owner == (u64)-1) {
736 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
737 ret = btrfs_next_leaf(root, path);
741 leaf = path->nodes[0];
743 btrfs_item_key_to_cpu(leaf, &found_key,
745 BUG_ON(key.objectid != found_key.objectid);
746 if (found_key.type != BTRFS_EXTENT_REF_V0_KEY) {
750 ref0 = btrfs_item_ptr(leaf, path->slots[0],
751 struct btrfs_extent_ref_v0);
752 owner = btrfs_ref_objectid_v0(leaf, ref0);
756 btrfs_release_path(root, path);
758 if (owner < BTRFS_FIRST_FREE_OBJECTID)
759 new_size += sizeof(*bi);
761 new_size -= sizeof(*ei0);
762 ret = btrfs_search_slot(trans, root, &key, path,
763 new_size + extra_size, 1);
768 ret = btrfs_extend_item(trans, root, path, new_size);
771 leaf = path->nodes[0];
772 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
773 btrfs_set_extent_refs(leaf, item, refs);
774 /* FIXME: get real generation */
775 btrfs_set_extent_generation(leaf, item, 0);
776 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
777 btrfs_set_extent_flags(leaf, item,
778 BTRFS_EXTENT_FLAG_TREE_BLOCK |
779 BTRFS_BLOCK_FLAG_FULL_BACKREF);
780 bi = (struct btrfs_tree_block_info *)(item + 1);
781 /* FIXME: get first key of the block */
782 memset_extent_buffer(leaf, 0, (unsigned long)bi, sizeof(*bi));
783 btrfs_set_tree_block_level(leaf, bi, (int)owner);
785 btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_DATA);
787 btrfs_mark_buffer_dirty(leaf);
792 static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
794 u32 high_crc = ~(u32)0;
795 u32 low_crc = ~(u32)0;
798 lenum = cpu_to_le64(root_objectid);
799 high_crc = crc32c(high_crc, &lenum, sizeof(lenum));
800 lenum = cpu_to_le64(owner);
801 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
802 lenum = cpu_to_le64(offset);
803 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
805 return ((u64)high_crc << 31) ^ (u64)low_crc;
808 static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
809 struct btrfs_extent_data_ref *ref)
811 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
812 btrfs_extent_data_ref_objectid(leaf, ref),
813 btrfs_extent_data_ref_offset(leaf, ref));
816 static int match_extent_data_ref(struct extent_buffer *leaf,
817 struct btrfs_extent_data_ref *ref,
818 u64 root_objectid, u64 owner, u64 offset)
820 if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
821 btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
822 btrfs_extent_data_ref_offset(leaf, ref) != offset)
827 static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
828 struct btrfs_root *root,
829 struct btrfs_path *path,
830 u64 bytenr, u64 parent,
832 u64 owner, u64 offset)
834 struct btrfs_key key;
835 struct btrfs_extent_data_ref *ref;
836 struct extent_buffer *leaf;
842 key.objectid = bytenr;
844 key.type = BTRFS_SHARED_DATA_REF_KEY;
847 key.type = BTRFS_EXTENT_DATA_REF_KEY;
848 key.offset = hash_extent_data_ref(root_objectid,
853 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
862 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
863 key.type = BTRFS_EXTENT_REF_V0_KEY;
864 btrfs_release_path(root, path);
865 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
876 leaf = path->nodes[0];
877 nritems = btrfs_header_nritems(leaf);
879 if (path->slots[0] >= nritems) {
880 ret = btrfs_next_leaf(root, path);
886 leaf = path->nodes[0];
887 nritems = btrfs_header_nritems(leaf);
891 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
892 if (key.objectid != bytenr ||
893 key.type != BTRFS_EXTENT_DATA_REF_KEY)
896 ref = btrfs_item_ptr(leaf, path->slots[0],
897 struct btrfs_extent_data_ref);
899 if (match_extent_data_ref(leaf, ref, root_objectid,
902 btrfs_release_path(root, path);
914 static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
915 struct btrfs_root *root,
916 struct btrfs_path *path,
917 u64 bytenr, u64 parent,
918 u64 root_objectid, u64 owner,
919 u64 offset, int refs_to_add)
921 struct btrfs_key key;
922 struct extent_buffer *leaf;
927 key.objectid = bytenr;
929 key.type = BTRFS_SHARED_DATA_REF_KEY;
931 size = sizeof(struct btrfs_shared_data_ref);
933 key.type = BTRFS_EXTENT_DATA_REF_KEY;
934 key.offset = hash_extent_data_ref(root_objectid,
936 size = sizeof(struct btrfs_extent_data_ref);
939 ret = btrfs_insert_empty_item(trans, root, path, &key, size);
940 if (ret && ret != -EEXIST)
943 leaf = path->nodes[0];
945 struct btrfs_shared_data_ref *ref;
946 ref = btrfs_item_ptr(leaf, path->slots[0],
947 struct btrfs_shared_data_ref);
949 btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
951 num_refs = btrfs_shared_data_ref_count(leaf, ref);
952 num_refs += refs_to_add;
953 btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
956 struct btrfs_extent_data_ref *ref;
957 while (ret == -EEXIST) {
958 ref = btrfs_item_ptr(leaf, path->slots[0],
959 struct btrfs_extent_data_ref);
960 if (match_extent_data_ref(leaf, ref, root_objectid,
963 btrfs_release_path(root, path);
965 ret = btrfs_insert_empty_item(trans, root, path, &key,
967 if (ret && ret != -EEXIST)
970 leaf = path->nodes[0];
972 ref = btrfs_item_ptr(leaf, path->slots[0],
973 struct btrfs_extent_data_ref);
975 btrfs_set_extent_data_ref_root(leaf, ref,
977 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
978 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
979 btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
981 num_refs = btrfs_extent_data_ref_count(leaf, ref);
982 num_refs += refs_to_add;
983 btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
986 btrfs_mark_buffer_dirty(leaf);
989 btrfs_release_path(root, path);
993 static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
994 struct btrfs_root *root,
995 struct btrfs_path *path,
998 struct btrfs_key key;
999 struct btrfs_extent_data_ref *ref1 = NULL;
1000 struct btrfs_shared_data_ref *ref2 = NULL;
1001 struct extent_buffer *leaf;
1005 leaf = path->nodes[0];
1006 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1008 if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1009 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1010 struct btrfs_extent_data_ref);
1011 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1012 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1013 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1014 struct btrfs_shared_data_ref);
1015 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1016 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1017 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1018 struct btrfs_extent_ref_v0 *ref0;
1019 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1020 struct btrfs_extent_ref_v0);
1021 num_refs = btrfs_ref_count_v0(leaf, ref0);
1027 BUG_ON(num_refs < refs_to_drop);
1028 num_refs -= refs_to_drop;
1030 if (num_refs == 0) {
1031 ret = btrfs_del_item(trans, root, path);
1033 if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
1034 btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
1035 else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
1036 btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
1037 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1039 struct btrfs_extent_ref_v0 *ref0;
1040 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1041 struct btrfs_extent_ref_v0);
1042 btrfs_set_ref_count_v0(leaf, ref0, num_refs);
1045 btrfs_mark_buffer_dirty(leaf);
1050 static noinline u32 extent_data_ref_count(struct btrfs_root *root,
1051 struct btrfs_path *path,
1052 struct btrfs_extent_inline_ref *iref)
1054 struct btrfs_key key;
1055 struct extent_buffer *leaf;
1056 struct btrfs_extent_data_ref *ref1;
1057 struct btrfs_shared_data_ref *ref2;
1060 leaf = path->nodes[0];
1061 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1063 if (btrfs_extent_inline_ref_type(leaf, iref) ==
1064 BTRFS_EXTENT_DATA_REF_KEY) {
1065 ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
1066 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1068 ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
1069 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1071 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1072 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1073 struct btrfs_extent_data_ref);
1074 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1075 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1076 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1077 struct btrfs_shared_data_ref);
1078 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1079 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1080 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1081 struct btrfs_extent_ref_v0 *ref0;
1082 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1083 struct btrfs_extent_ref_v0);
1084 num_refs = btrfs_ref_count_v0(leaf, ref0);
1092 static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
1093 struct btrfs_root *root,
1094 struct btrfs_path *path,
1095 u64 bytenr, u64 parent,
1098 struct btrfs_key key;
1101 key.objectid = bytenr;
1103 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1104 key.offset = parent;
1106 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1107 key.offset = root_objectid;
1110 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1113 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1114 if (ret == -ENOENT && parent) {
1115 btrfs_release_path(root, path);
1116 key.type = BTRFS_EXTENT_REF_V0_KEY;
1117 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1125 static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
1126 struct btrfs_root *root,
1127 struct btrfs_path *path,
1128 u64 bytenr, u64 parent,
1131 struct btrfs_key key;
1134 key.objectid = bytenr;
1136 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1137 key.offset = parent;
1139 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1140 key.offset = root_objectid;
1143 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1144 btrfs_release_path(root, path);
1148 static inline int extent_ref_type(u64 parent, u64 owner)
1151 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1153 type = BTRFS_SHARED_BLOCK_REF_KEY;
1155 type = BTRFS_TREE_BLOCK_REF_KEY;
1158 type = BTRFS_SHARED_DATA_REF_KEY;
1160 type = BTRFS_EXTENT_DATA_REF_KEY;
1165 static int find_next_key(struct btrfs_path *path, int level,
1166 struct btrfs_key *key)
1169 for (; level < BTRFS_MAX_LEVEL; level++) {
1170 if (!path->nodes[level])
1172 if (path->slots[level] + 1 >=
1173 btrfs_header_nritems(path->nodes[level]))
1176 btrfs_item_key_to_cpu(path->nodes[level], key,
1177 path->slots[level] + 1);
1179 btrfs_node_key_to_cpu(path->nodes[level], key,
1180 path->slots[level] + 1);
1187 * look for inline back ref. if back ref is found, *ref_ret is set
1188 * to the address of inline back ref, and 0 is returned.
1190 * if back ref isn't found, *ref_ret is set to the address where it
1191 * should be inserted, and -ENOENT is returned.
1193 * if insert is true and there are too many inline back refs, the path
1194 * points to the extent item, and -EAGAIN is returned.
1196 * NOTE: inline back refs are ordered in the same way that back ref
1197 * items in the tree are ordered.
1199 static noinline_for_stack
1200 int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
1201 struct btrfs_root *root,
1202 struct btrfs_path *path,
1203 struct btrfs_extent_inline_ref **ref_ret,
1204 u64 bytenr, u64 num_bytes,
1205 u64 parent, u64 root_objectid,
1206 u64 owner, u64 offset, int insert)
1208 struct btrfs_key key;
1209 struct extent_buffer *leaf;
1210 struct btrfs_extent_item *ei;
1211 struct btrfs_extent_inline_ref *iref;
1222 key.objectid = bytenr;
1223 key.type = BTRFS_EXTENT_ITEM_KEY;
1224 key.offset = num_bytes;
1226 want = extent_ref_type(parent, owner);
1228 extra_size = btrfs_extent_inline_ref_size(want);
1229 path->keep_locks = 1;
1232 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
1239 leaf = path->nodes[0];
1240 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1241 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1242 if (item_size < sizeof(*ei)) {
1247 ret = convert_extent_item_v0(trans, root, path, owner,
1253 leaf = path->nodes[0];
1254 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1257 BUG_ON(item_size < sizeof(*ei));
1259 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1260 flags = btrfs_extent_flags(leaf, ei);
1262 ptr = (unsigned long)(ei + 1);
1263 end = (unsigned long)ei + item_size;
1265 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
1266 ptr += sizeof(struct btrfs_tree_block_info);
1269 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_DATA));
1278 iref = (struct btrfs_extent_inline_ref *)ptr;
1279 type = btrfs_extent_inline_ref_type(leaf, iref);
1283 ptr += btrfs_extent_inline_ref_size(type);
1287 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1288 struct btrfs_extent_data_ref *dref;
1289 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1290 if (match_extent_data_ref(leaf, dref, root_objectid,
1295 if (hash_extent_data_ref_item(leaf, dref) <
1296 hash_extent_data_ref(root_objectid, owner, offset))
1300 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1302 if (parent == ref_offset) {
1306 if (ref_offset < parent)
1309 if (root_objectid == ref_offset) {
1313 if (ref_offset < root_objectid)
1317 ptr += btrfs_extent_inline_ref_size(type);
1319 if (err == -ENOENT && insert) {
1320 if (item_size + extra_size >=
1321 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
1326 * To add new inline back ref, we have to make sure
1327 * there is no corresponding back ref item.
1328 * For simplicity, we just do not add new inline back
1329 * ref if there is any kind of item for this block
1331 if (find_next_key(path, 0, &key) == 0 &&
1332 key.objectid == bytenr &&
1333 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
1338 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
1341 path->keep_locks = 0;
1342 btrfs_unlock_up_safe(path, 1);
1348 * helper to add new inline back ref
1350 static noinline_for_stack
1351 int setup_inline_extent_backref(struct btrfs_trans_handle *trans,
1352 struct btrfs_root *root,
1353 struct btrfs_path *path,
1354 struct btrfs_extent_inline_ref *iref,
1355 u64 parent, u64 root_objectid,
1356 u64 owner, u64 offset, int refs_to_add,
1357 struct btrfs_delayed_extent_op *extent_op)
1359 struct extent_buffer *leaf;
1360 struct btrfs_extent_item *ei;
1363 unsigned long item_offset;
1369 leaf = path->nodes[0];
1370 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1371 item_offset = (unsigned long)iref - (unsigned long)ei;
1373 type = extent_ref_type(parent, owner);
1374 size = btrfs_extent_inline_ref_size(type);
1376 ret = btrfs_extend_item(trans, root, path, size);
1379 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1380 refs = btrfs_extent_refs(leaf, ei);
1381 refs += refs_to_add;
1382 btrfs_set_extent_refs(leaf, ei, refs);
1384 __run_delayed_extent_op(extent_op, leaf, ei);
1386 ptr = (unsigned long)ei + item_offset;
1387 end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
1388 if (ptr < end - size)
1389 memmove_extent_buffer(leaf, ptr + size, ptr,
1392 iref = (struct btrfs_extent_inline_ref *)ptr;
1393 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1394 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1395 struct btrfs_extent_data_ref *dref;
1396 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1397 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1398 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1399 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1400 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1401 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1402 struct btrfs_shared_data_ref *sref;
1403 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1404 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1405 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1406 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1407 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1409 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1411 btrfs_mark_buffer_dirty(leaf);
1415 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1416 struct btrfs_root *root,
1417 struct btrfs_path *path,
1418 struct btrfs_extent_inline_ref **ref_ret,
1419 u64 bytenr, u64 num_bytes, u64 parent,
1420 u64 root_objectid, u64 owner, u64 offset)
1424 ret = lookup_inline_extent_backref(trans, root, path, ref_ret,
1425 bytenr, num_bytes, parent,
1426 root_objectid, owner, offset, 0);
1430 btrfs_release_path(root, path);
1433 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1434 ret = lookup_tree_block_ref(trans, root, path, bytenr, parent,
1437 ret = lookup_extent_data_ref(trans, root, path, bytenr, parent,
1438 root_objectid, owner, offset);
1444 * helper to update/remove inline back ref
1446 static noinline_for_stack
1447 int update_inline_extent_backref(struct btrfs_trans_handle *trans,
1448 struct btrfs_root *root,
1449 struct btrfs_path *path,
1450 struct btrfs_extent_inline_ref *iref,
1452 struct btrfs_delayed_extent_op *extent_op)
1454 struct extent_buffer *leaf;
1455 struct btrfs_extent_item *ei;
1456 struct btrfs_extent_data_ref *dref = NULL;
1457 struct btrfs_shared_data_ref *sref = NULL;
1466 leaf = path->nodes[0];
1467 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1468 refs = btrfs_extent_refs(leaf, ei);
1469 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1470 refs += refs_to_mod;
1471 btrfs_set_extent_refs(leaf, ei, refs);
1473 __run_delayed_extent_op(extent_op, leaf, ei);
1475 type = btrfs_extent_inline_ref_type(leaf, iref);
1477 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1478 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1479 refs = btrfs_extent_data_ref_count(leaf, dref);
1480 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1481 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1482 refs = btrfs_shared_data_ref_count(leaf, sref);
1485 BUG_ON(refs_to_mod != -1);
1488 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1489 refs += refs_to_mod;
1492 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1493 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1495 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1497 size = btrfs_extent_inline_ref_size(type);
1498 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1499 ptr = (unsigned long)iref;
1500 end = (unsigned long)ei + item_size;
1501 if (ptr + size < end)
1502 memmove_extent_buffer(leaf, ptr, ptr + size,
1505 ret = btrfs_truncate_item(trans, root, path, item_size, 1);
1508 btrfs_mark_buffer_dirty(leaf);
1512 static noinline_for_stack
1513 int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1514 struct btrfs_root *root,
1515 struct btrfs_path *path,
1516 u64 bytenr, u64 num_bytes, u64 parent,
1517 u64 root_objectid, u64 owner,
1518 u64 offset, int refs_to_add,
1519 struct btrfs_delayed_extent_op *extent_op)
1521 struct btrfs_extent_inline_ref *iref;
1524 ret = lookup_inline_extent_backref(trans, root, path, &iref,
1525 bytenr, num_bytes, parent,
1526 root_objectid, owner, offset, 1);
1528 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
1529 ret = update_inline_extent_backref(trans, root, path, iref,
1530 refs_to_add, extent_op);
1531 } else if (ret == -ENOENT) {
1532 ret = setup_inline_extent_backref(trans, root, path, iref,
1533 parent, root_objectid,
1534 owner, offset, refs_to_add,
1540 static int insert_extent_backref(struct btrfs_trans_handle *trans,
1541 struct btrfs_root *root,
1542 struct btrfs_path *path,
1543 u64 bytenr, u64 parent, u64 root_objectid,
1544 u64 owner, u64 offset, int refs_to_add)
1547 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1548 BUG_ON(refs_to_add != 1);
1549 ret = insert_tree_block_ref(trans, root, path, bytenr,
1550 parent, root_objectid);
1552 ret = insert_extent_data_ref(trans, root, path, bytenr,
1553 parent, root_objectid,
1554 owner, offset, refs_to_add);
1559 static int remove_extent_backref(struct btrfs_trans_handle *trans,
1560 struct btrfs_root *root,
1561 struct btrfs_path *path,
1562 struct btrfs_extent_inline_ref *iref,
1563 int refs_to_drop, int is_data)
1567 BUG_ON(!is_data && refs_to_drop != 1);
1569 ret = update_inline_extent_backref(trans, root, path, iref,
1570 -refs_to_drop, NULL);
1571 } else if (is_data) {
1572 ret = remove_extent_data_ref(trans, root, path, refs_to_drop);
1574 ret = btrfs_del_item(trans, root, path);
1579 static void btrfs_issue_discard(struct block_device *bdev,
1582 blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_KERNEL,
1583 DISCARD_FL_BARRIER);
1586 static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
1590 u64 map_length = num_bytes;
1591 struct btrfs_multi_bio *multi = NULL;
1593 if (!btrfs_test_opt(root, DISCARD))
1596 /* Tell the block device(s) that the sectors can be discarded */
1597 ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
1598 bytenr, &map_length, &multi, 0);
1600 struct btrfs_bio_stripe *stripe = multi->stripes;
1603 if (map_length > num_bytes)
1604 map_length = num_bytes;
1606 for (i = 0; i < multi->num_stripes; i++, stripe++) {
1607 btrfs_issue_discard(stripe->dev->bdev,
1617 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1618 struct btrfs_root *root,
1619 u64 bytenr, u64 num_bytes, u64 parent,
1620 u64 root_objectid, u64 owner, u64 offset)
1623 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID &&
1624 root_objectid == BTRFS_TREE_LOG_OBJECTID);
1626 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1627 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
1628 parent, root_objectid, (int)owner,
1629 BTRFS_ADD_DELAYED_REF, NULL);
1631 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
1632 parent, root_objectid, owner, offset,
1633 BTRFS_ADD_DELAYED_REF, NULL);
1638 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1639 struct btrfs_root *root,
1640 u64 bytenr, u64 num_bytes,
1641 u64 parent, u64 root_objectid,
1642 u64 owner, u64 offset, int refs_to_add,
1643 struct btrfs_delayed_extent_op *extent_op)
1645 struct btrfs_path *path;
1646 struct extent_buffer *leaf;
1647 struct btrfs_extent_item *item;
1652 path = btrfs_alloc_path();
1657 path->leave_spinning = 1;
1658 /* this will setup the path even if it fails to insert the back ref */
1659 ret = insert_inline_extent_backref(trans, root->fs_info->extent_root,
1660 path, bytenr, num_bytes, parent,
1661 root_objectid, owner, offset,
1662 refs_to_add, extent_op);
1666 if (ret != -EAGAIN) {
1671 leaf = path->nodes[0];
1672 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1673 refs = btrfs_extent_refs(leaf, item);
1674 btrfs_set_extent_refs(leaf, item, refs + refs_to_add);
1676 __run_delayed_extent_op(extent_op, leaf, item);
1678 btrfs_mark_buffer_dirty(leaf);
1679 btrfs_release_path(root->fs_info->extent_root, path);
1682 path->leave_spinning = 1;
1684 /* now insert the actual backref */
1685 ret = insert_extent_backref(trans, root->fs_info->extent_root,
1686 path, bytenr, parent, root_objectid,
1687 owner, offset, refs_to_add);
1690 btrfs_free_path(path);
1694 static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
1695 struct btrfs_root *root,
1696 struct btrfs_delayed_ref_node *node,
1697 struct btrfs_delayed_extent_op *extent_op,
1698 int insert_reserved)
1701 struct btrfs_delayed_data_ref *ref;
1702 struct btrfs_key ins;
1707 ins.objectid = node->bytenr;
1708 ins.offset = node->num_bytes;
1709 ins.type = BTRFS_EXTENT_ITEM_KEY;
1711 ref = btrfs_delayed_node_to_data_ref(node);
1712 if (node->type == BTRFS_SHARED_DATA_REF_KEY)
1713 parent = ref->parent;
1715 ref_root = ref->root;
1717 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
1719 BUG_ON(extent_op->update_key);
1720 flags |= extent_op->flags_to_set;
1722 ret = alloc_reserved_file_extent(trans, root,
1723 parent, ref_root, flags,
1724 ref->objectid, ref->offset,
1725 &ins, node->ref_mod);
1726 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
1727 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
1728 node->num_bytes, parent,
1729 ref_root, ref->objectid,
1730 ref->offset, node->ref_mod,
1732 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
1733 ret = __btrfs_free_extent(trans, root, node->bytenr,
1734 node->num_bytes, parent,
1735 ref_root, ref->objectid,
1736 ref->offset, node->ref_mod,
1744 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
1745 struct extent_buffer *leaf,
1746 struct btrfs_extent_item *ei)
1748 u64 flags = btrfs_extent_flags(leaf, ei);
1749 if (extent_op->update_flags) {
1750 flags |= extent_op->flags_to_set;
1751 btrfs_set_extent_flags(leaf, ei, flags);
1754 if (extent_op->update_key) {
1755 struct btrfs_tree_block_info *bi;
1756 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK));
1757 bi = (struct btrfs_tree_block_info *)(ei + 1);
1758 btrfs_set_tree_block_key(leaf, bi, &extent_op->key);
1762 static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
1763 struct btrfs_root *root,
1764 struct btrfs_delayed_ref_node *node,
1765 struct btrfs_delayed_extent_op *extent_op)
1767 struct btrfs_key key;
1768 struct btrfs_path *path;
1769 struct btrfs_extent_item *ei;
1770 struct extent_buffer *leaf;
1775 path = btrfs_alloc_path();
1779 key.objectid = node->bytenr;
1780 key.type = BTRFS_EXTENT_ITEM_KEY;
1781 key.offset = node->num_bytes;
1784 path->leave_spinning = 1;
1785 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key,
1796 leaf = path->nodes[0];
1797 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1798 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1799 if (item_size < sizeof(*ei)) {
1800 ret = convert_extent_item_v0(trans, root->fs_info->extent_root,
1806 leaf = path->nodes[0];
1807 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1810 BUG_ON(item_size < sizeof(*ei));
1811 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1812 __run_delayed_extent_op(extent_op, leaf, ei);
1814 btrfs_mark_buffer_dirty(leaf);
1816 btrfs_free_path(path);
1820 static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
1821 struct btrfs_root *root,
1822 struct btrfs_delayed_ref_node *node,
1823 struct btrfs_delayed_extent_op *extent_op,
1824 int insert_reserved)
1827 struct btrfs_delayed_tree_ref *ref;
1828 struct btrfs_key ins;
1832 ins.objectid = node->bytenr;
1833 ins.offset = node->num_bytes;
1834 ins.type = BTRFS_EXTENT_ITEM_KEY;
1836 ref = btrfs_delayed_node_to_tree_ref(node);
1837 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
1838 parent = ref->parent;
1840 ref_root = ref->root;
1842 BUG_ON(node->ref_mod != 1);
1843 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
1844 BUG_ON(!extent_op || !extent_op->update_flags ||
1845 !extent_op->update_key);
1846 ret = alloc_reserved_tree_block(trans, root,
1848 extent_op->flags_to_set,
1851 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
1852 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
1853 node->num_bytes, parent, ref_root,
1854 ref->level, 0, 1, extent_op);
1855 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
1856 ret = __btrfs_free_extent(trans, root, node->bytenr,
1857 node->num_bytes, parent, ref_root,
1858 ref->level, 0, 1, extent_op);
1866 /* helper function to actually process a single delayed ref entry */
1867 static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
1868 struct btrfs_root *root,
1869 struct btrfs_delayed_ref_node *node,
1870 struct btrfs_delayed_extent_op *extent_op,
1871 int insert_reserved)
1874 if (btrfs_delayed_ref_is_head(node)) {
1875 struct btrfs_delayed_ref_head *head;
1877 * we've hit the end of the chain and we were supposed
1878 * to insert this extent into the tree. But, it got
1879 * deleted before we ever needed to insert it, so all
1880 * we have to do is clean up the accounting
1883 head = btrfs_delayed_node_to_head(node);
1884 if (insert_reserved) {
1886 struct extent_buffer *must_clean = NULL;
1888 ret = pin_down_bytes(trans, root, NULL,
1889 node->bytenr, node->num_bytes,
1890 head->is_data, 1, &must_clean);
1895 clean_tree_block(NULL, root, must_clean);
1896 btrfs_tree_unlock(must_clean);
1897 free_extent_buffer(must_clean);
1899 if (head->is_data) {
1900 ret = btrfs_del_csums(trans, root,
1906 ret = btrfs_free_reserved_extent(root,
1912 mutex_unlock(&head->mutex);
1916 if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
1917 node->type == BTRFS_SHARED_BLOCK_REF_KEY)
1918 ret = run_delayed_tree_ref(trans, root, node, extent_op,
1920 else if (node->type == BTRFS_EXTENT_DATA_REF_KEY ||
1921 node->type == BTRFS_SHARED_DATA_REF_KEY)
1922 ret = run_delayed_data_ref(trans, root, node, extent_op,
1929 static noinline struct btrfs_delayed_ref_node *
1930 select_delayed_ref(struct btrfs_delayed_ref_head *head)
1932 struct rb_node *node;
1933 struct btrfs_delayed_ref_node *ref;
1934 int action = BTRFS_ADD_DELAYED_REF;
1937 * select delayed ref of type BTRFS_ADD_DELAYED_REF first.
1938 * this prevents ref count from going down to zero when
1939 * there still are pending delayed ref.
1941 node = rb_prev(&head->node.rb_node);
1945 ref = rb_entry(node, struct btrfs_delayed_ref_node,
1947 if (ref->bytenr != head->node.bytenr)
1949 if (ref->action == action)
1951 node = rb_prev(node);
1953 if (action == BTRFS_ADD_DELAYED_REF) {
1954 action = BTRFS_DROP_DELAYED_REF;
1960 static noinline int run_clustered_refs(struct btrfs_trans_handle *trans,
1961 struct btrfs_root *root,
1962 struct list_head *cluster)
1964 struct btrfs_delayed_ref_root *delayed_refs;
1965 struct btrfs_delayed_ref_node *ref;
1966 struct btrfs_delayed_ref_head *locked_ref = NULL;
1967 struct btrfs_delayed_extent_op *extent_op;
1970 int must_insert_reserved = 0;
1972 delayed_refs = &trans->transaction->delayed_refs;
1975 /* pick a new head ref from the cluster list */
1976 if (list_empty(cluster))
1979 locked_ref = list_entry(cluster->next,
1980 struct btrfs_delayed_ref_head, cluster);
1982 /* grab the lock that says we are going to process
1983 * all the refs for this head */
1984 ret = btrfs_delayed_ref_lock(trans, locked_ref);
1987 * we may have dropped the spin lock to get the head
1988 * mutex lock, and that might have given someone else
1989 * time to free the head. If that's true, it has been
1990 * removed from our list and we can move on.
1992 if (ret == -EAGAIN) {
2000 * record the must insert reserved flag before we
2001 * drop the spin lock.
2003 must_insert_reserved = locked_ref->must_insert_reserved;
2004 locked_ref->must_insert_reserved = 0;
2006 extent_op = locked_ref->extent_op;
2007 locked_ref->extent_op = NULL;
2010 * locked_ref is the head node, so we have to go one
2011 * node back for any delayed ref updates
2013 ref = select_delayed_ref(locked_ref);
2015 /* All delayed refs have been processed, Go ahead
2016 * and send the head node to run_one_delayed_ref,
2017 * so that any accounting fixes can happen
2019 ref = &locked_ref->node;
2021 if (extent_op && must_insert_reserved) {
2027 spin_unlock(&delayed_refs->lock);
2029 ret = run_delayed_extent_op(trans, root,
2035 spin_lock(&delayed_refs->lock);
2039 list_del_init(&locked_ref->cluster);
2044 rb_erase(&ref->rb_node, &delayed_refs->root);
2045 delayed_refs->num_entries--;
2047 spin_unlock(&delayed_refs->lock);
2049 ret = run_one_delayed_ref(trans, root, ref, extent_op,
2050 must_insert_reserved);
2053 btrfs_put_delayed_ref(ref);
2058 spin_lock(&delayed_refs->lock);
2064 * this starts processing the delayed reference count updates and
2065 * extent insertions we have queued up so far. count can be
2066 * 0, which means to process everything in the tree at the start
2067 * of the run (but not newly added entries), or it can be some target
2068 * number you'd like to process.
2070 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2071 struct btrfs_root *root, unsigned long count)
2073 struct rb_node *node;
2074 struct btrfs_delayed_ref_root *delayed_refs;
2075 struct btrfs_delayed_ref_node *ref;
2076 struct list_head cluster;
2078 int run_all = count == (unsigned long)-1;
2081 if (root == root->fs_info->extent_root)
2082 root = root->fs_info->tree_root;
2084 delayed_refs = &trans->transaction->delayed_refs;
2085 INIT_LIST_HEAD(&cluster);
2087 spin_lock(&delayed_refs->lock);
2089 count = delayed_refs->num_entries * 2;
2093 if (!(run_all || run_most) &&
2094 delayed_refs->num_heads_ready < 64)
2098 * go find something we can process in the rbtree. We start at
2099 * the beginning of the tree, and then build a cluster
2100 * of refs to process starting at the first one we are able to
2103 ret = btrfs_find_ref_cluster(trans, &cluster,
2104 delayed_refs->run_delayed_start);
2108 ret = run_clustered_refs(trans, root, &cluster);
2111 count -= min_t(unsigned long, ret, count);
2118 node = rb_first(&delayed_refs->root);
2121 count = (unsigned long)-1;
2124 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2126 if (btrfs_delayed_ref_is_head(ref)) {
2127 struct btrfs_delayed_ref_head *head;
2129 head = btrfs_delayed_node_to_head(ref);
2130 atomic_inc(&ref->refs);
2132 spin_unlock(&delayed_refs->lock);
2133 mutex_lock(&head->mutex);
2134 mutex_unlock(&head->mutex);
2136 btrfs_put_delayed_ref(ref);
2140 node = rb_next(node);
2142 spin_unlock(&delayed_refs->lock);
2143 schedule_timeout(1);
2147 spin_unlock(&delayed_refs->lock);
2151 int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
2152 struct btrfs_root *root,
2153 u64 bytenr, u64 num_bytes, u64 flags,
2156 struct btrfs_delayed_extent_op *extent_op;
2159 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
2163 extent_op->flags_to_set = flags;
2164 extent_op->update_flags = 1;
2165 extent_op->update_key = 0;
2166 extent_op->is_data = is_data ? 1 : 0;
2168 ret = btrfs_add_delayed_extent_op(trans, bytenr, num_bytes, extent_op);
2174 static noinline int check_delayed_ref(struct btrfs_trans_handle *trans,
2175 struct btrfs_root *root,
2176 struct btrfs_path *path,
2177 u64 objectid, u64 offset, u64 bytenr)
2179 struct btrfs_delayed_ref_head *head;
2180 struct btrfs_delayed_ref_node *ref;
2181 struct btrfs_delayed_data_ref *data_ref;
2182 struct btrfs_delayed_ref_root *delayed_refs;
2183 struct rb_node *node;
2187 delayed_refs = &trans->transaction->delayed_refs;
2188 spin_lock(&delayed_refs->lock);
2189 head = btrfs_find_delayed_ref_head(trans, bytenr);
2193 if (!mutex_trylock(&head->mutex)) {
2194 atomic_inc(&head->node.refs);
2195 spin_unlock(&delayed_refs->lock);
2197 btrfs_release_path(root->fs_info->extent_root, path);
2199 mutex_lock(&head->mutex);
2200 mutex_unlock(&head->mutex);
2201 btrfs_put_delayed_ref(&head->node);
2205 node = rb_prev(&head->node.rb_node);
2209 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2211 if (ref->bytenr != bytenr)
2215 if (ref->type != BTRFS_EXTENT_DATA_REF_KEY)
2218 data_ref = btrfs_delayed_node_to_data_ref(ref);
2220 node = rb_prev(node);
2222 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2223 if (ref->bytenr == bytenr)
2227 if (data_ref->root != root->root_key.objectid ||
2228 data_ref->objectid != objectid || data_ref->offset != offset)
2233 mutex_unlock(&head->mutex);
2235 spin_unlock(&delayed_refs->lock);
2239 static noinline int check_committed_ref(struct btrfs_trans_handle *trans,
2240 struct btrfs_root *root,
2241 struct btrfs_path *path,
2242 u64 objectid, u64 offset, u64 bytenr)
2244 struct btrfs_root *extent_root = root->fs_info->extent_root;
2245 struct extent_buffer *leaf;
2246 struct btrfs_extent_data_ref *ref;
2247 struct btrfs_extent_inline_ref *iref;
2248 struct btrfs_extent_item *ei;
2249 struct btrfs_key key;
2253 key.objectid = bytenr;
2254 key.offset = (u64)-1;
2255 key.type = BTRFS_EXTENT_ITEM_KEY;
2257 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
2263 if (path->slots[0] == 0)
2267 leaf = path->nodes[0];
2268 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2270 if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY)
2274 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2275 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2276 if (item_size < sizeof(*ei)) {
2277 WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0));
2281 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2283 if (item_size != sizeof(*ei) +
2284 btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY))
2287 if (btrfs_extent_generation(leaf, ei) <=
2288 btrfs_root_last_snapshot(&root->root_item))
2291 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
2292 if (btrfs_extent_inline_ref_type(leaf, iref) !=
2293 BTRFS_EXTENT_DATA_REF_KEY)
2296 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
2297 if (btrfs_extent_refs(leaf, ei) !=
2298 btrfs_extent_data_ref_count(leaf, ref) ||
2299 btrfs_extent_data_ref_root(leaf, ref) !=
2300 root->root_key.objectid ||
2301 btrfs_extent_data_ref_objectid(leaf, ref) != objectid ||
2302 btrfs_extent_data_ref_offset(leaf, ref) != offset)
2310 int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans,
2311 struct btrfs_root *root,
2312 u64 objectid, u64 offset, u64 bytenr)
2314 struct btrfs_path *path;
2318 path = btrfs_alloc_path();
2323 ret = check_committed_ref(trans, root, path, objectid,
2325 if (ret && ret != -ENOENT)
2328 ret2 = check_delayed_ref(trans, root, path, objectid,
2330 } while (ret2 == -EAGAIN);
2332 if (ret2 && ret2 != -ENOENT) {
2337 if (ret != -ENOENT || ret2 != -ENOENT)
2340 btrfs_free_path(path);
2345 int btrfs_cache_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2346 struct extent_buffer *buf, u32 nr_extents)
2348 struct btrfs_key key;
2349 struct btrfs_file_extent_item *fi;
2357 if (!root->ref_cows)
2360 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
2362 root_gen = root->root_key.offset;
2365 root_gen = trans->transid - 1;
2368 level = btrfs_header_level(buf);
2369 nritems = btrfs_header_nritems(buf);
2372 struct btrfs_leaf_ref *ref;
2373 struct btrfs_extent_info *info;
2375 ref = btrfs_alloc_leaf_ref(root, nr_extents);
2381 ref->root_gen = root_gen;
2382 ref->bytenr = buf->start;
2383 ref->owner = btrfs_header_owner(buf);
2384 ref->generation = btrfs_header_generation(buf);
2385 ref->nritems = nr_extents;
2386 info = ref->extents;
2388 for (i = 0; nr_extents > 0 && i < nritems; i++) {
2390 btrfs_item_key_to_cpu(buf, &key, i);
2391 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2393 fi = btrfs_item_ptr(buf, i,
2394 struct btrfs_file_extent_item);
2395 if (btrfs_file_extent_type(buf, fi) ==
2396 BTRFS_FILE_EXTENT_INLINE)
2398 disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2399 if (disk_bytenr == 0)
2402 info->bytenr = disk_bytenr;
2404 btrfs_file_extent_disk_num_bytes(buf, fi);
2405 info->objectid = key.objectid;
2406 info->offset = key.offset;
2410 ret = btrfs_add_leaf_ref(root, ref, shared);
2411 if (ret == -EEXIST && shared) {
2412 struct btrfs_leaf_ref *old;
2413 old = btrfs_lookup_leaf_ref(root, ref->bytenr);
2415 btrfs_remove_leaf_ref(root, old);
2416 btrfs_free_leaf_ref(root, old);
2417 ret = btrfs_add_leaf_ref(root, ref, shared);
2420 btrfs_free_leaf_ref(root, ref);
2426 /* when a block goes through cow, we update the reference counts of
2427 * everything that block points to. The internal pointers of the block
2428 * can be in just about any order, and it is likely to have clusters of
2429 * things that are close together and clusters of things that are not.
2431 * To help reduce the seeks that come with updating all of these reference
2432 * counts, sort them by byte number before actual updates are done.
2434 * struct refsort is used to match byte number to slot in the btree block.
2435 * we sort based on the byte number and then use the slot to actually
2438 * struct refsort is smaller than strcut btrfs_item and smaller than
2439 * struct btrfs_key_ptr. Since we're currently limited to the page size
2440 * for a btree block, there's no way for a kmalloc of refsorts for a
2441 * single node to be bigger than a page.
2449 * for passing into sort()
2451 static int refsort_cmp(const void *a_void, const void *b_void)
2453 const struct refsort *a = a_void;
2454 const struct refsort *b = b_void;
2456 if (a->bytenr < b->bytenr)
2458 if (a->bytenr > b->bytenr)
2464 static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
2465 struct btrfs_root *root,
2466 struct extent_buffer *buf,
2467 int full_backref, int inc)
2474 struct btrfs_key key;
2475 struct btrfs_file_extent_item *fi;
2479 int (*process_func)(struct btrfs_trans_handle *, struct btrfs_root *,
2480 u64, u64, u64, u64, u64, u64);
2482 ref_root = btrfs_header_owner(buf);
2483 nritems = btrfs_header_nritems(buf);
2484 level = btrfs_header_level(buf);
2486 if (!root->ref_cows && level == 0)
2490 process_func = btrfs_inc_extent_ref;
2492 process_func = btrfs_free_extent;
2495 parent = buf->start;
2499 for (i = 0; i < nritems; i++) {
2501 btrfs_item_key_to_cpu(buf, &key, i);
2502 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2504 fi = btrfs_item_ptr(buf, i,
2505 struct btrfs_file_extent_item);
2506 if (btrfs_file_extent_type(buf, fi) ==
2507 BTRFS_FILE_EXTENT_INLINE)
2509 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2513 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
2514 key.offset -= btrfs_file_extent_offset(buf, fi);
2515 ret = process_func(trans, root, bytenr, num_bytes,
2516 parent, ref_root, key.objectid,
2521 bytenr = btrfs_node_blockptr(buf, i);
2522 num_bytes = btrfs_level_size(root, level - 1);
2523 ret = process_func(trans, root, bytenr, num_bytes,
2524 parent, ref_root, level - 1, 0);
2535 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2536 struct extent_buffer *buf, int full_backref)
2538 return __btrfs_mod_ref(trans, root, buf, full_backref, 1);
2541 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2542 struct extent_buffer *buf, int full_backref)
2544 return __btrfs_mod_ref(trans, root, buf, full_backref, 0);
2547 static int write_one_cache_group(struct btrfs_trans_handle *trans,
2548 struct btrfs_root *root,
2549 struct btrfs_path *path,
2550 struct btrfs_block_group_cache *cache)
2553 struct btrfs_root *extent_root = root->fs_info->extent_root;
2555 struct extent_buffer *leaf;
2557 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
2562 leaf = path->nodes[0];
2563 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
2564 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
2565 btrfs_mark_buffer_dirty(leaf);
2566 btrfs_release_path(extent_root, path);
2574 static struct btrfs_block_group_cache *
2575 next_block_group(struct btrfs_root *root,
2576 struct btrfs_block_group_cache *cache)
2578 struct rb_node *node;
2579 spin_lock(&root->fs_info->block_group_cache_lock);
2580 node = rb_next(&cache->cache_node);
2581 btrfs_put_block_group(cache);
2583 cache = rb_entry(node, struct btrfs_block_group_cache,
2585 atomic_inc(&cache->count);
2588 spin_unlock(&root->fs_info->block_group_cache_lock);
2592 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
2593 struct btrfs_root *root)
2595 struct btrfs_block_group_cache *cache;
2597 struct btrfs_path *path;
2600 path = btrfs_alloc_path();
2606 err = btrfs_run_delayed_refs(trans, root,
2611 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2615 cache = next_block_group(root, cache);
2625 last = cache->key.objectid + cache->key.offset;
2627 err = write_one_cache_group(trans, root, path, cache);
2629 btrfs_put_block_group(cache);
2632 btrfs_free_path(path);
2636 int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr)
2638 struct btrfs_block_group_cache *block_group;
2641 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
2642 if (!block_group || block_group->ro)
2645 btrfs_put_block_group(block_group);
2649 static int update_space_info(struct btrfs_fs_info *info, u64 flags,
2650 u64 total_bytes, u64 bytes_used,
2651 struct btrfs_space_info **space_info)
2653 struct btrfs_space_info *found;
2655 found = __find_space_info(info, flags);
2657 spin_lock(&found->lock);
2658 found->total_bytes += total_bytes;
2659 found->bytes_used += bytes_used;
2661 spin_unlock(&found->lock);
2662 *space_info = found;
2665 found = kzalloc(sizeof(*found), GFP_NOFS);
2669 INIT_LIST_HEAD(&found->block_groups);
2670 init_rwsem(&found->groups_sem);
2671 spin_lock_init(&found->lock);
2672 found->flags = flags;
2673 found->total_bytes = total_bytes;
2674 found->bytes_used = bytes_used;
2675 found->bytes_pinned = 0;
2676 found->bytes_reserved = 0;
2677 found->bytes_readonly = 0;
2678 found->bytes_delalloc = 0;
2680 found->force_alloc = 0;
2681 *space_info = found;
2682 list_add_rcu(&found->list, &info->space_info);
2683 atomic_set(&found->caching_threads, 0);
2687 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
2689 u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 |
2690 BTRFS_BLOCK_GROUP_RAID1 |
2691 BTRFS_BLOCK_GROUP_RAID10 |
2692 BTRFS_BLOCK_GROUP_DUP);
2694 if (flags & BTRFS_BLOCK_GROUP_DATA)
2695 fs_info->avail_data_alloc_bits |= extra_flags;
2696 if (flags & BTRFS_BLOCK_GROUP_METADATA)
2697 fs_info->avail_metadata_alloc_bits |= extra_flags;
2698 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
2699 fs_info->avail_system_alloc_bits |= extra_flags;
2703 static void set_block_group_readonly(struct btrfs_block_group_cache *cache)
2705 spin_lock(&cache->space_info->lock);
2706 spin_lock(&cache->lock);
2708 cache->space_info->bytes_readonly += cache->key.offset -
2709 btrfs_block_group_used(&cache->item);
2712 spin_unlock(&cache->lock);
2713 spin_unlock(&cache->space_info->lock);
2716 u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
2718 u64 num_devices = root->fs_info->fs_devices->rw_devices;
2720 if (num_devices == 1)
2721 flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0);
2722 if (num_devices < 4)
2723 flags &= ~BTRFS_BLOCK_GROUP_RAID10;
2725 if ((flags & BTRFS_BLOCK_GROUP_DUP) &&
2726 (flags & (BTRFS_BLOCK_GROUP_RAID1 |
2727 BTRFS_BLOCK_GROUP_RAID10))) {
2728 flags &= ~BTRFS_BLOCK_GROUP_DUP;
2731 if ((flags & BTRFS_BLOCK_GROUP_RAID1) &&
2732 (flags & BTRFS_BLOCK_GROUP_RAID10)) {
2733 flags &= ~BTRFS_BLOCK_GROUP_RAID1;
2736 if ((flags & BTRFS_BLOCK_GROUP_RAID0) &&
2737 ((flags & BTRFS_BLOCK_GROUP_RAID1) |
2738 (flags & BTRFS_BLOCK_GROUP_RAID10) |
2739 (flags & BTRFS_BLOCK_GROUP_DUP)))
2740 flags &= ~BTRFS_BLOCK_GROUP_RAID0;
2744 static u64 btrfs_get_alloc_profile(struct btrfs_root *root, u64 data)
2746 struct btrfs_fs_info *info = root->fs_info;
2750 alloc_profile = info->avail_data_alloc_bits &
2751 info->data_alloc_profile;
2752 data = BTRFS_BLOCK_GROUP_DATA | alloc_profile;
2753 } else if (root == root->fs_info->chunk_root) {
2754 alloc_profile = info->avail_system_alloc_bits &
2755 info->system_alloc_profile;
2756 data = BTRFS_BLOCK_GROUP_SYSTEM | alloc_profile;
2758 alloc_profile = info->avail_metadata_alloc_bits &
2759 info->metadata_alloc_profile;
2760 data = BTRFS_BLOCK_GROUP_METADATA | alloc_profile;
2763 return btrfs_reduce_alloc_profile(root, data);
2766 void btrfs_set_inode_space_info(struct btrfs_root *root, struct inode *inode)
2770 alloc_target = btrfs_get_alloc_profile(root, 1);
2771 BTRFS_I(inode)->space_info = __find_space_info(root->fs_info,
2775 static u64 calculate_bytes_needed(struct btrfs_root *root, int num_items)
2780 level = BTRFS_MAX_LEVEL - 2;
2782 * NOTE: these calculations are absolutely the worst possible case.
2783 * This assumes that _every_ item we insert will require a new leaf, and
2784 * that the tree has grown to its maximum level size.
2788 * for every item we insert we could insert both an extent item and a
2789 * extent ref item. Then for ever item we insert, we will need to cow
2790 * both the original leaf, plus the leaf to the left and right of it.
2792 * Unless we are talking about the extent root, then we just want the
2793 * number of items * 2, since we just need the extent item plus its ref.
2795 if (root == root->fs_info->extent_root)
2796 num_bytes = num_items * 2;
2798 num_bytes = (num_items + (2 * num_items)) * 3;
2801 * num_bytes is total number of leaves we could need times the leaf
2802 * size, and then for every leaf we could end up cow'ing 2 nodes per
2803 * level, down to the leaf level.
2805 num_bytes = (num_bytes * root->leafsize) +
2806 (num_bytes * (level * 2)) * root->nodesize;
2812 * Unreserve metadata space for delalloc. If we have less reserved credits than
2813 * we have extents, this function does nothing.
2815 int btrfs_unreserve_metadata_for_delalloc(struct btrfs_root *root,
2816 struct inode *inode, int num_items)
2818 struct btrfs_fs_info *info = root->fs_info;
2819 struct btrfs_space_info *meta_sinfo;
2824 /* get the space info for where the metadata will live */
2825 alloc_target = btrfs_get_alloc_profile(root, 0);
2826 meta_sinfo = __find_space_info(info, alloc_target);
2828 num_bytes = calculate_bytes_needed(root->fs_info->extent_root,
2831 spin_lock(&meta_sinfo->lock);
2832 spin_lock(&BTRFS_I(inode)->accounting_lock);
2833 if (BTRFS_I(inode)->reserved_extents <=
2834 BTRFS_I(inode)->outstanding_extents) {
2835 spin_unlock(&BTRFS_I(inode)->accounting_lock);
2836 spin_unlock(&meta_sinfo->lock);
2839 spin_unlock(&BTRFS_I(inode)->accounting_lock);
2841 BTRFS_I(inode)->reserved_extents--;
2842 BUG_ON(BTRFS_I(inode)->reserved_extents < 0);
2844 if (meta_sinfo->bytes_delalloc < num_bytes) {
2846 meta_sinfo->bytes_delalloc = 0;
2848 meta_sinfo->bytes_delalloc -= num_bytes;
2850 spin_unlock(&meta_sinfo->lock);
2857 static void check_force_delalloc(struct btrfs_space_info *meta_sinfo)
2861 thresh = meta_sinfo->bytes_used + meta_sinfo->bytes_reserved +
2862 meta_sinfo->bytes_pinned + meta_sinfo->bytes_readonly +
2863 meta_sinfo->bytes_super + meta_sinfo->bytes_root +
2864 meta_sinfo->bytes_may_use;
2866 thresh = meta_sinfo->total_bytes - thresh;
2868 do_div(thresh, 100);
2869 if (thresh <= meta_sinfo->bytes_delalloc)
2870 meta_sinfo->force_delalloc = 1;
2872 meta_sinfo->force_delalloc = 0;
2875 struct async_flush {
2876 struct btrfs_root *root;
2877 struct btrfs_space_info *info;
2878 struct btrfs_work work;
2881 static noinline void flush_delalloc_async(struct btrfs_work *work)
2883 struct async_flush *async;
2884 struct btrfs_root *root;
2885 struct btrfs_space_info *info;
2887 async = container_of(work, struct async_flush, work);
2891 btrfs_start_delalloc_inodes(root, 0);
2892 wake_up(&info->flush_wait);
2893 btrfs_wait_ordered_extents(root, 0, 0);
2895 spin_lock(&info->lock);
2897 spin_unlock(&info->lock);
2898 wake_up(&info->flush_wait);
2903 static void wait_on_flush(struct btrfs_space_info *info)
2909 prepare_to_wait(&info->flush_wait, &wait,
2910 TASK_UNINTERRUPTIBLE);
2911 spin_lock(&info->lock);
2912 if (!info->flushing) {
2913 spin_unlock(&info->lock);
2917 used = info->bytes_used + info->bytes_reserved +
2918 info->bytes_pinned + info->bytes_readonly +
2919 info->bytes_super + info->bytes_root +
2920 info->bytes_may_use + info->bytes_delalloc;
2921 if (used < info->total_bytes) {
2922 spin_unlock(&info->lock);
2925 spin_unlock(&info->lock);
2928 finish_wait(&info->flush_wait, &wait);
2931 static void flush_delalloc(struct btrfs_root *root,
2932 struct btrfs_space_info *info)
2934 struct async_flush *async;
2937 spin_lock(&info->lock);
2939 if (!info->flushing) {
2941 init_waitqueue_head(&info->flush_wait);
2946 spin_unlock(&info->lock);
2949 wait_on_flush(info);
2953 async = kzalloc(sizeof(*async), GFP_NOFS);
2959 async->work.func = flush_delalloc_async;
2961 btrfs_queue_worker(&root->fs_info->enospc_workers,
2963 wait_on_flush(info);
2967 btrfs_start_delalloc_inodes(root, 0);
2968 btrfs_wait_ordered_extents(root, 0, 0);
2970 spin_lock(&info->lock);
2972 spin_unlock(&info->lock);
2973 wake_up(&info->flush_wait);
2976 static int maybe_allocate_chunk(struct btrfs_root *root,
2977 struct btrfs_space_info *info)
2979 struct btrfs_super_block *disk_super = &root->fs_info->super_copy;
2980 struct btrfs_trans_handle *trans;
2986 free_space = btrfs_super_total_bytes(disk_super);
2988 * we allow the metadata to grow to a max of either 10gb or 5% of the
2989 * space in the volume.
2991 min_metadata = min((u64)10 * 1024 * 1024 * 1024,
2992 div64_u64(free_space * 5, 100));
2993 if (info->total_bytes >= min_metadata) {
2994 spin_unlock(&info->lock);
2999 spin_unlock(&info->lock);
3003 if (!info->allocating_chunk) {
3004 info->force_alloc = 1;
3005 info->allocating_chunk = 1;
3006 init_waitqueue_head(&info->allocate_wait);
3011 spin_unlock(&info->lock);
3014 wait_event(info->allocate_wait,
3015 !info->allocating_chunk);
3019 trans = btrfs_start_transaction(root, 1);
3025 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
3026 4096 + 2 * 1024 * 1024,
3028 btrfs_end_transaction(trans, root);
3032 spin_lock(&info->lock);
3033 info->allocating_chunk = 0;
3034 spin_unlock(&info->lock);
3035 wake_up(&info->allocate_wait);
3043 * Reserve metadata space for delalloc.
3045 int btrfs_reserve_metadata_for_delalloc(struct btrfs_root *root,
3046 struct inode *inode, int num_items)
3048 struct btrfs_fs_info *info = root->fs_info;
3049 struct btrfs_space_info *meta_sinfo;
3056 /* get the space info for where the metadata will live */
3057 alloc_target = btrfs_get_alloc_profile(root, 0);
3058 meta_sinfo = __find_space_info(info, alloc_target);
3060 num_bytes = calculate_bytes_needed(root->fs_info->extent_root,
3063 spin_lock(&meta_sinfo->lock);
3065 force_delalloc = meta_sinfo->force_delalloc;
3067 if (unlikely(!meta_sinfo->bytes_root))
3068 meta_sinfo->bytes_root = calculate_bytes_needed(root, 6);
3071 meta_sinfo->bytes_delalloc += num_bytes;
3073 used = meta_sinfo->bytes_used + meta_sinfo->bytes_reserved +
3074 meta_sinfo->bytes_pinned + meta_sinfo->bytes_readonly +
3075 meta_sinfo->bytes_super + meta_sinfo->bytes_root +
3076 meta_sinfo->bytes_may_use + meta_sinfo->bytes_delalloc;
3078 if (used > meta_sinfo->total_bytes) {
3082 if (maybe_allocate_chunk(root, meta_sinfo))
3086 spin_unlock(&meta_sinfo->lock);
3090 filemap_flush(inode->i_mapping);
3092 } else if (flushed == 3) {
3093 flush_delalloc(root, meta_sinfo);
3096 spin_lock(&meta_sinfo->lock);
3097 meta_sinfo->bytes_delalloc -= num_bytes;
3098 spin_unlock(&meta_sinfo->lock);
3099 printk(KERN_ERR "enospc, has %d, reserved %d\n",
3100 BTRFS_I(inode)->outstanding_extents,
3101 BTRFS_I(inode)->reserved_extents);
3102 dump_space_info(meta_sinfo, 0, 0);
3106 BTRFS_I(inode)->reserved_extents++;
3107 check_force_delalloc(meta_sinfo);
3108 spin_unlock(&meta_sinfo->lock);
3110 if (!flushed && force_delalloc)
3111 filemap_flush(inode->i_mapping);
3117 * unreserve num_items number of items worth of metadata space. This needs to
3118 * be paired with btrfs_reserve_metadata_space.
3120 * NOTE: if you have the option, run this _AFTER_ you do a
3121 * btrfs_end_transaction, since btrfs_end_transaction will run delayed ref
3122 * oprations which will result in more used metadata, so we want to make sure we
3123 * can do that without issue.
3125 int btrfs_unreserve_metadata_space(struct btrfs_root *root, int num_items)
3127 struct btrfs_fs_info *info = root->fs_info;
3128 struct btrfs_space_info *meta_sinfo;
3133 /* get the space info for where the metadata will live */
3134 alloc_target = btrfs_get_alloc_profile(root, 0);
3135 meta_sinfo = __find_space_info(info, alloc_target);
3137 num_bytes = calculate_bytes_needed(root, num_items);
3139 spin_lock(&meta_sinfo->lock);
3140 if (meta_sinfo->bytes_may_use < num_bytes) {
3142 meta_sinfo->bytes_may_use = 0;
3144 meta_sinfo->bytes_may_use -= num_bytes;
3146 spin_unlock(&meta_sinfo->lock);
3154 * Reserve some metadata space for use. We'll calculate the worste case number
3155 * of bytes that would be needed to modify num_items number of items. If we
3156 * have space, fantastic, if not, you get -ENOSPC. Please call
3157 * btrfs_unreserve_metadata_space when you are done for the _SAME_ number of
3158 * items you reserved, since whatever metadata you needed should have already
3161 * This will commit the transaction to make more space if we don't have enough
3162 * metadata space. THe only time we don't do this is if we're reserving space
3163 * inside of a transaction, then we will just return -ENOSPC and it is the
3164 * callers responsibility to handle it properly.
3166 int btrfs_reserve_metadata_space(struct btrfs_root *root, int num_items)
3168 struct btrfs_fs_info *info = root->fs_info;
3169 struct btrfs_space_info *meta_sinfo;
3175 /* get the space info for where the metadata will live */
3176 alloc_target = btrfs_get_alloc_profile(root, 0);
3177 meta_sinfo = __find_space_info(info, alloc_target);
3179 num_bytes = calculate_bytes_needed(root, num_items);
3181 spin_lock(&meta_sinfo->lock);
3183 if (unlikely(!meta_sinfo->bytes_root))
3184 meta_sinfo->bytes_root = calculate_bytes_needed(root, 6);
3187 meta_sinfo->bytes_may_use += num_bytes;
3189 used = meta_sinfo->bytes_used + meta_sinfo->bytes_reserved +
3190 meta_sinfo->bytes_pinned + meta_sinfo->bytes_readonly +
3191 meta_sinfo->bytes_super + meta_sinfo->bytes_root +
3192 meta_sinfo->bytes_may_use + meta_sinfo->bytes_delalloc;
3194 if (used > meta_sinfo->total_bytes) {
3197 if (maybe_allocate_chunk(root, meta_sinfo))
3201 spin_unlock(&meta_sinfo->lock);
3205 flush_delalloc(root, meta_sinfo);
3208 spin_lock(&meta_sinfo->lock);
3209 meta_sinfo->bytes_may_use -= num_bytes;
3210 spin_unlock(&meta_sinfo->lock);
3212 dump_space_info(meta_sinfo, 0, 0);
3216 check_force_delalloc(meta_sinfo);
3217 spin_unlock(&meta_sinfo->lock);
3223 * This will check the space that the inode allocates from to make sure we have
3224 * enough space for bytes.
3226 int btrfs_check_data_free_space(struct btrfs_root *root, struct inode *inode,
3229 struct btrfs_space_info *data_sinfo;
3230 int ret = 0, committed = 0;
3232 /* make sure bytes are sectorsize aligned */
3233 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3235 data_sinfo = BTRFS_I(inode)->space_info;
3240 /* make sure we have enough space to handle the data first */
3241 spin_lock(&data_sinfo->lock);
3242 if (data_sinfo->total_bytes - data_sinfo->bytes_used -
3243 data_sinfo->bytes_delalloc - data_sinfo->bytes_reserved -
3244 data_sinfo->bytes_pinned - data_sinfo->bytes_readonly -
3245 data_sinfo->bytes_may_use - data_sinfo->bytes_super < bytes) {
3246 struct btrfs_trans_handle *trans;
3249 * if we don't have enough free bytes in this space then we need
3250 * to alloc a new chunk.
3252 if (!data_sinfo->full) {
3255 data_sinfo->force_alloc = 1;
3256 spin_unlock(&data_sinfo->lock);
3258 alloc_target = btrfs_get_alloc_profile(root, 1);
3259 trans = btrfs_start_transaction(root, 1);
3263 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
3264 bytes + 2 * 1024 * 1024,
3266 btrfs_end_transaction(trans, root);
3271 btrfs_set_inode_space_info(root, inode);
3272 data_sinfo = BTRFS_I(inode)->space_info;
3276 spin_unlock(&data_sinfo->lock);
3278 /* commit the current transaction and try again */
3279 if (!committed && !root->fs_info->open_ioctl_trans) {
3281 trans = btrfs_join_transaction(root, 1);
3284 ret = btrfs_commit_transaction(trans, root);
3290 printk(KERN_ERR "no space left, need %llu, %llu delalloc bytes"
3291 ", %llu bytes_used, %llu bytes_reserved, "
3292 "%llu bytes_pinned, %llu bytes_readonly, %llu may use "
3293 "%llu total\n", (unsigned long long)bytes,
3294 (unsigned long long)data_sinfo->bytes_delalloc,
3295 (unsigned long long)data_sinfo->bytes_used,
3296 (unsigned long long)data_sinfo->bytes_reserved,
3297 (unsigned long long)data_sinfo->bytes_pinned,
3298 (unsigned long long)data_sinfo->bytes_readonly,
3299 (unsigned long long)data_sinfo->bytes_may_use,
3300 (unsigned long long)data_sinfo->total_bytes);
3303 data_sinfo->bytes_may_use += bytes;
3304 BTRFS_I(inode)->reserved_bytes += bytes;
3305 spin_unlock(&data_sinfo->lock);
3311 * if there was an error for whatever reason after calling
3312 * btrfs_check_data_free_space, call this so we can cleanup the counters.
3314 void btrfs_free_reserved_data_space(struct btrfs_root *root,
3315 struct inode *inode, u64 bytes)
3317 struct btrfs_space_info *data_sinfo;
3319 /* make sure bytes are sectorsize aligned */
3320 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
3322 data_sinfo = BTRFS_I(inode)->space_info;
3323 spin_lock(&data_sinfo->lock);
3324 data_sinfo->bytes_may_use -= bytes;
3325 BTRFS_I(inode)->reserved_bytes -= bytes;
3326 spin_unlock(&data_sinfo->lock);
3329 /* called when we are adding a delalloc extent to the inode's io_tree */
3330 void btrfs_delalloc_reserve_space(struct btrfs_root *root, struct inode *inode,
3333 struct btrfs_space_info *data_sinfo;
3335 /* get the space info for where this inode will be storing its data */
3336 data_sinfo = BTRFS_I(inode)->space_info;
3338 /* make sure we have enough space to handle the data first */
3339 spin_lock(&data_sinfo->lock);
3340 data_sinfo->bytes_delalloc += bytes;
3343 * we are adding a delalloc extent without calling
3344 * btrfs_check_data_free_space first. This happens on a weird
3345 * writepage condition, but shouldn't hurt our accounting
3347 if (unlikely(bytes > BTRFS_I(inode)->reserved_bytes)) {
3348 data_sinfo->bytes_may_use -= BTRFS_I(inode)->reserved_bytes;
3349 BTRFS_I(inode)->reserved_bytes = 0;
3351 data_sinfo->bytes_may_use -= bytes;
3352 BTRFS_I(inode)->reserved_bytes -= bytes;
3355 spin_unlock(&data_sinfo->lock);
3358 /* called when we are clearing an delalloc extent from the inode's io_tree */
3359 void btrfs_delalloc_free_space(struct btrfs_root *root, struct inode *inode,
3362 struct btrfs_space_info *info;
3364 info = BTRFS_I(inode)->space_info;
3366 spin_lock(&info->lock);
3367 info->bytes_delalloc -= bytes;
3368 spin_unlock(&info->lock);
3371 static void force_metadata_allocation(struct btrfs_fs_info *info)
3373 struct list_head *head = &info->space_info;
3374 struct btrfs_space_info *found;
3377 list_for_each_entry_rcu(found, head, list) {
3378 if (found->flags & BTRFS_BLOCK_GROUP_METADATA)
3379 found->force_alloc = 1;
3384 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
3385 struct btrfs_root *extent_root, u64 alloc_bytes,
3386 u64 flags, int force)
3388 struct btrfs_space_info *space_info;
3389 struct btrfs_fs_info *fs_info = extent_root->fs_info;
3393 mutex_lock(&fs_info->chunk_mutex);
3395 flags = btrfs_reduce_alloc_profile(extent_root, flags);
3397 space_info = __find_space_info(extent_root->fs_info, flags);
3399 ret = update_space_info(extent_root->fs_info, flags,
3403 BUG_ON(!space_info);
3405 spin_lock(&space_info->lock);
3406 if (space_info->force_alloc)
3408 if (space_info->full) {
3409 spin_unlock(&space_info->lock);
3413 thresh = space_info->total_bytes - space_info->bytes_readonly;
3414 thresh = div_factor(thresh, 8);
3416 (space_info->bytes_used + space_info->bytes_pinned +
3417 space_info->bytes_reserved + alloc_bytes) < thresh) {
3418 spin_unlock(&space_info->lock);
3421 spin_unlock(&space_info->lock);
3424 * if we're doing a data chunk, go ahead and make sure that
3425 * we keep a reasonable number of metadata chunks allocated in the
3428 if (flags & BTRFS_BLOCK_GROUP_DATA && fs_info->metadata_ratio) {
3429 fs_info->data_chunk_allocations++;
3430 if (!(fs_info->data_chunk_allocations %
3431 fs_info->metadata_ratio))
3432 force_metadata_allocation(fs_info);
3435 ret = btrfs_alloc_chunk(trans, extent_root, flags);
3436 spin_lock(&space_info->lock);
3438 space_info->full = 1;
3439 space_info->force_alloc = 0;
3440 spin_unlock(&space_info->lock);
3442 mutex_unlock(&extent_root->fs_info->chunk_mutex);
3446 static int update_block_group(struct btrfs_trans_handle *trans,
3447 struct btrfs_root *root,
3448 u64 bytenr, u64 num_bytes, int alloc,
3451 struct btrfs_block_group_cache *cache;
3452 struct btrfs_fs_info *info = root->fs_info;
3453 u64 total = num_bytes;
3457 /* block accounting for super block */
3458 spin_lock(&info->delalloc_lock);
3459 old_val = btrfs_super_bytes_used(&info->super_copy);
3461 old_val += num_bytes;
3463 old_val -= num_bytes;
3464 btrfs_set_super_bytes_used(&info->super_copy, old_val);
3465 spin_unlock(&info->delalloc_lock);
3468 cache = btrfs_lookup_block_group(info, bytenr);
3471 byte_in_group = bytenr - cache->key.objectid;
3472 WARN_ON(byte_in_group > cache->key.offset);
3474 spin_lock(&cache->space_info->lock);
3475 spin_lock(&cache->lock);
3477 old_val = btrfs_block_group_used(&cache->item);
3478 num_bytes = min(total, cache->key.offset - byte_in_group);
3480 old_val += num_bytes;
3481 btrfs_set_block_group_used(&cache->item, old_val);
3482 cache->reserved -= num_bytes;
3483 cache->space_info->bytes_used += num_bytes;
3484 cache->space_info->bytes_reserved -= num_bytes;
3486 cache->space_info->bytes_readonly -= num_bytes;
3487 spin_unlock(&cache->lock);
3488 spin_unlock(&cache->space_info->lock);
3490 old_val -= num_bytes;
3491 cache->space_info->bytes_used -= num_bytes;
3493 cache->space_info->bytes_readonly += num_bytes;
3494 btrfs_set_block_group_used(&cache->item, old_val);
3495 spin_unlock(&cache->lock);
3496 spin_unlock(&cache->space_info->lock);
3500 ret = btrfs_discard_extent(root, bytenr,
3504 ret = btrfs_add_free_space(cache, bytenr,
3509 btrfs_put_block_group(cache);
3511 bytenr += num_bytes;
3516 static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
3518 struct btrfs_block_group_cache *cache;
3521 cache = btrfs_lookup_first_block_group(root->fs_info, search_start);
3525 bytenr = cache->key.objectid;
3526 btrfs_put_block_group(cache);
3532 * this function must be called within transaction
3534 int btrfs_pin_extent(struct btrfs_root *root,
3535 u64 bytenr, u64 num_bytes, int reserved)
3537 struct btrfs_fs_info *fs_info = root->fs_info;
3538 struct btrfs_block_group_cache *cache;
3540 cache = btrfs_lookup_block_group(fs_info, bytenr);
3543 spin_lock(&cache->space_info->lock);
3544 spin_lock(&cache->lock);
3545 cache->pinned += num_bytes;
3546 cache->space_info->bytes_pinned += num_bytes;
3548 cache->reserved -= num_bytes;
3549 cache->space_info->bytes_reserved -= num_bytes;
3551 spin_unlock(&cache->lock);
3552 spin_unlock(&cache->space_info->lock);
3554 btrfs_put_block_group(cache);
3556 set_extent_dirty(fs_info->pinned_extents,
3557 bytenr, bytenr + num_bytes - 1, GFP_NOFS);
3561 static int update_reserved_extents(struct btrfs_block_group_cache *cache,
3562 u64 num_bytes, int reserve)
3564 spin_lock(&cache->space_info->lock);
3565 spin_lock(&cache->lock);
3567 cache->reserved += num_bytes;
3568 cache->space_info->bytes_reserved += num_bytes;
3570 cache->reserved -= num_bytes;
3571 cache->space_info->bytes_reserved -= num_bytes;
3573 spin_unlock(&cache->lock);
3574 spin_unlock(&cache->space_info->lock);
3578 int btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
3579 struct btrfs_root *root)
3581 struct btrfs_fs_info *fs_info = root->fs_info;
3582 struct btrfs_caching_control *next;
3583 struct btrfs_caching_control *caching_ctl;
3584 struct btrfs_block_group_cache *cache;
3586 down_write(&fs_info->extent_commit_sem);
3588 list_for_each_entry_safe(caching_ctl, next,
3589 &fs_info->caching_block_groups, list) {
3590 cache = caching_ctl->block_group;
3591 if (block_group_cache_done(cache)) {
3592 cache->last_byte_to_unpin = (u64)-1;
3593 list_del_init(&caching_ctl->list);
3594 put_caching_control(caching_ctl);
3596 cache->last_byte_to_unpin = caching_ctl->progress;
3600 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
3601 fs_info->pinned_extents = &fs_info->freed_extents[1];
3603 fs_info->pinned_extents = &fs_info->freed_extents[0];
3605 up_write(&fs_info->extent_commit_sem);
3609 static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
3611 struct btrfs_fs_info *fs_info = root->fs_info;
3612 struct btrfs_block_group_cache *cache = NULL;
3615 while (start <= end) {
3617 start >= cache->key.objectid + cache->key.offset) {
3619 btrfs_put_block_group(cache);
3620 cache = btrfs_lookup_block_group(fs_info, start);
3624 len = cache->key.objectid + cache->key.offset - start;
3625 len = min(len, end + 1 - start);
3627 if (start < cache->last_byte_to_unpin) {
3628 len = min(len, cache->last_byte_to_unpin - start);
3629 btrfs_add_free_space(cache, start, len);
3632 spin_lock(&cache->space_info->lock);
3633 spin_lock(&cache->lock);
3634 cache->pinned -= len;
3635 cache->space_info->bytes_pinned -= len;
3636 spin_unlock(&cache->lock);
3637 spin_unlock(&cache->space_info->lock);
3643 btrfs_put_block_group(cache);
3647 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
3648 struct btrfs_root *root)
3650 struct btrfs_fs_info *fs_info = root->fs_info;
3651 struct extent_io_tree *unpin;
3656 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
3657 unpin = &fs_info->freed_extents[1];
3659 unpin = &fs_info->freed_extents[0];
3662 ret = find_first_extent_bit(unpin, 0, &start, &end,
3667 ret = btrfs_discard_extent(root, start, end + 1 - start);
3669 clear_extent_dirty(unpin, start, end, GFP_NOFS);
3670 unpin_extent_range(root, start, end);
3677 static int pin_down_bytes(struct btrfs_trans_handle *trans,
3678 struct btrfs_root *root,
3679 struct btrfs_path *path,
3680 u64 bytenr, u64 num_bytes,
3681 int is_data, int reserved,
3682 struct extent_buffer **must_clean)
3685 struct extent_buffer *buf;
3691 * discard is sloooow, and so triggering discards on
3692 * individual btree blocks isn't a good plan. Just
3693 * pin everything in discard mode.
3695 if (btrfs_test_opt(root, DISCARD))
3698 buf = btrfs_find_tree_block(root, bytenr, num_bytes);
3702 /* we can reuse a block if it hasn't been written
3703 * and it is from this transaction. We can't
3704 * reuse anything from the tree log root because
3705 * it has tiny sub-transactions.
3707 if (btrfs_buffer_uptodate(buf, 0) &&
3708 btrfs_try_tree_lock(buf)) {
3709 u64 header_owner = btrfs_header_owner(buf);
3710 u64 header_transid = btrfs_header_generation(buf);
3711 if (header_owner != BTRFS_TREE_LOG_OBJECTID &&
3712 header_transid == trans->transid &&
3713 !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
3717 btrfs_tree_unlock(buf);
3719 free_extent_buffer(buf);
3722 btrfs_set_path_blocking(path);
3723 /* unlocks the pinned mutex */
3724 btrfs_pin_extent(root, bytenr, num_bytes, reserved);
3730 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
3731 struct btrfs_root *root,
3732 u64 bytenr, u64 num_bytes, u64 parent,
3733 u64 root_objectid, u64 owner_objectid,
3734 u64 owner_offset, int refs_to_drop,
3735 struct btrfs_delayed_extent_op *extent_op)
3737 struct btrfs_key key;
3738 struct btrfs_path *path;
3739 struct btrfs_fs_info *info = root->fs_info;
3740 struct btrfs_root *extent_root = info->extent_root;
3741 struct extent_buffer *leaf;
3742 struct btrfs_extent_item *ei;
3743 struct btrfs_extent_inline_ref *iref;
3746 int extent_slot = 0;
3747 int found_extent = 0;
3752 path = btrfs_alloc_path();
3757 path->leave_spinning = 1;
3759 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
3760 BUG_ON(!is_data && refs_to_drop != 1);
3762 ret = lookup_extent_backref(trans, extent_root, path, &iref,
3763 bytenr, num_bytes, parent,
3764 root_objectid, owner_objectid,
3767 extent_slot = path->slots[0];
3768 while (extent_slot >= 0) {
3769 btrfs_item_key_to_cpu(path->nodes[0], &key,
3771 if (key.objectid != bytenr)
3773 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
3774 key.offset == num_bytes) {
3778 if (path->slots[0] - extent_slot > 5)
3782 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
3783 item_size = btrfs_item_size_nr(path->nodes[0], extent_slot);
3784 if (found_extent && item_size < sizeof(*ei))
3787 if (!found_extent) {
3789 ret = remove_extent_backref(trans, extent_root, path,
3793 btrfs_release_path(extent_root, path);
3794 path->leave_spinning = 1;
3796 key.objectid = bytenr;
3797 key.type = BTRFS_EXTENT_ITEM_KEY;
3798 key.offset = num_bytes;
3800 ret = btrfs_search_slot(trans, extent_root,
3803 printk(KERN_ERR "umm, got %d back from search"
3804 ", was looking for %llu\n", ret,
3805 (unsigned long long)bytenr);
3806 btrfs_print_leaf(extent_root, path->nodes[0]);
3809 extent_slot = path->slots[0];
3812 btrfs_print_leaf(extent_root, path->nodes[0]);
3814 printk(KERN_ERR "btrfs unable to find ref byte nr %llu "
3815 "parent %llu root %llu owner %llu offset %llu\n",
3816 (unsigned long long)bytenr,
3817 (unsigned long long)parent,
3818 (unsigned long long)root_objectid,
3819 (unsigned long long)owner_objectid,
3820 (unsigned long long)owner_offset);
3823 leaf = path->nodes[0];
3824 item_size = btrfs_item_size_nr(leaf, extent_slot);
3825 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
3826 if (item_size < sizeof(*ei)) {
3827 BUG_ON(found_extent || extent_slot != path->slots[0]);
3828 ret = convert_extent_item_v0(trans, extent_root, path,
3832 btrfs_release_path(extent_root, path);
3833 path->leave_spinning = 1;
3835 key.objectid = bytenr;
3836 key.type = BTRFS_EXTENT_ITEM_KEY;
3837 key.offset = num_bytes;
3839 ret = btrfs_search_slot(trans, extent_root, &key, path,
3842 printk(KERN_ERR "umm, got %d back from search"
3843 ", was looking for %llu\n", ret,
3844 (unsigned long long)bytenr);
3845 btrfs_print_leaf(extent_root, path->nodes[0]);
3848 extent_slot = path->slots[0];
3849 leaf = path->nodes[0];
3850 item_size = btrfs_item_size_nr(leaf, extent_slot);
3853 BUG_ON(item_size < sizeof(*ei));
3854 ei = btrfs_item_ptr(leaf, extent_slot,
3855 struct btrfs_extent_item);
3856 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID) {
3857 struct btrfs_tree_block_info *bi;
3858 BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
3859 bi = (struct btrfs_tree_block_info *)(ei + 1);
3860 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
3863 refs = btrfs_extent_refs(leaf, ei);
3864 BUG_ON(refs < refs_to_drop);
3865 refs -= refs_to_drop;
3869 __run_delayed_extent_op(extent_op, leaf, ei);
3871 * In the case of inline back ref, reference count will
3872 * be updated by remove_extent_backref
3875 BUG_ON(!found_extent);
3877 btrfs_set_extent_refs(leaf, ei, refs);
3878 btrfs_mark_buffer_dirty(leaf);
3881 ret = remove_extent_backref(trans, extent_root, path,
3888 struct extent_buffer *must_clean = NULL;
3891 BUG_ON(is_data && refs_to_drop !=
3892 extent_data_ref_count(root, path, iref));
3894 BUG_ON(path->slots[0] != extent_slot);
3896 BUG_ON(path->slots[0] != extent_slot + 1);
3897 path->slots[0] = extent_slot;
3902 ret = pin_down_bytes(trans, root, path, bytenr,
3903 num_bytes, is_data, 0, &must_clean);
3908 * it is going to be very rare for someone to be waiting
3909 * on the block we're freeing. del_items might need to
3910 * schedule, so rather than get fancy, just force it
3914 btrfs_set_lock_blocking(must_clean);
3916 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
3919 btrfs_release_path(extent_root, path);
3922 clean_tree_block(NULL, root, must_clean);
3923 btrfs_tree_unlock(must_clean);
3924 free_extent_buffer(must_clean);
3928 ret = btrfs_del_csums(trans, root, bytenr, num_bytes);
3931 invalidate_mapping_pages(info->btree_inode->i_mapping,
3932 bytenr >> PAGE_CACHE_SHIFT,
3933 (bytenr + num_bytes - 1) >> PAGE_CACHE_SHIFT);
3936 ret = update_block_group(trans, root, bytenr, num_bytes, 0,
3940 btrfs_free_path(path);
3945 * when we free an extent, it is possible (and likely) that we free the last
3946 * delayed ref for that extent as well. This searches the delayed ref tree for
3947 * a given extent, and if there are no other delayed refs to be processed, it
3948 * removes it from the tree.
3950 static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans,
3951 struct btrfs_root *root, u64 bytenr)
3953 struct btrfs_delayed_ref_head *head;
3954 struct btrfs_delayed_ref_root *delayed_refs;
3955 struct btrfs_delayed_ref_node *ref;
3956 struct rb_node *node;
3959 delayed_refs = &trans->transaction->delayed_refs;
3960 spin_lock(&delayed_refs->lock);
3961 head = btrfs_find_delayed_ref_head(trans, bytenr);
3965 node = rb_prev(&head->node.rb_node);
3969 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
3971 /* there are still entries for this ref, we can't drop it */
3972 if (ref->bytenr == bytenr)
3975 if (head->extent_op) {
3976 if (!head->must_insert_reserved)
3978 kfree(head->extent_op);
3979 head->extent_op = NULL;
3983 * waiting for the lock here would deadlock. If someone else has it
3984 * locked they are already in the process of dropping it anyway
3986 if (!mutex_trylock(&head->mutex))
3990 * at this point we have a head with no other entries. Go
3991 * ahead and process it.
3993 head->node.in_tree = 0;
3994 rb_erase(&head->node.rb_node, &delayed_refs->root);
3996 delayed_refs->num_entries--;
3999 * we don't take a ref on the node because we're removing it from the
4000 * tree, so we just steal the ref the tree was holding.
4002 delayed_refs->num_heads--;
4003 if (list_empty(&head->cluster))
4004 delayed_refs->num_heads_ready--;
4006 list_del_init(&head->cluster);
4007 spin_unlock(&delayed_refs->lock);
4009 ret = run_one_delayed_ref(trans, root->fs_info->tree_root,
4010 &head->node, head->extent_op,
4011 head->must_insert_reserved);
4013 btrfs_put_delayed_ref(&head->node);
4016 spin_unlock(&delayed_refs->lock);
4020 int btrfs_free_extent(struct btrfs_trans_handle *trans,
4021 struct btrfs_root *root,
4022 u64 bytenr, u64 num_bytes, u64 parent,
4023 u64 root_objectid, u64 owner, u64 offset)
4028 * tree log blocks never actually go into the extent allocation
4029 * tree, just update pinning info and exit early.
4031 if (root_objectid == BTRFS_TREE_LOG_OBJECTID) {
4032 WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID);
4033 /* unlocks the pinned mutex */
4034 btrfs_pin_extent(root, bytenr, num_bytes, 1);
4036 } else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
4037 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
4038 parent, root_objectid, (int)owner,
4039 BTRFS_DROP_DELAYED_REF, NULL);
4041 ret = check_ref_cleanup(trans, root, bytenr);
4044 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
4045 parent, root_objectid, owner,
4046 offset, BTRFS_DROP_DELAYED_REF, NULL);
4052 int btrfs_free_tree_block(struct btrfs_trans_handle *trans,
4053 struct btrfs_root *root,
4054 u64 bytenr, u32 blocksize,
4055 u64 parent, u64 root_objectid, int level)
4058 spin_lock(&root->node_lock);
4059 used = btrfs_root_used(&root->root_item) - blocksize;
4060 btrfs_set_root_used(&root->root_item, used);
4061 spin_unlock(&root->node_lock);
4063 return btrfs_free_extent(trans, root, bytenr, blocksize,
4064 parent, root_objectid, level, 0);
4067 static u64 stripe_align(struct btrfs_root *root, u64 val)
4069 u64 mask = ((u64)root->stripesize - 1);
4070 u64 ret = (val + mask) & ~mask;
4075 * when we wait for progress in the block group caching, its because
4076 * our allocation attempt failed at least once. So, we must sleep
4077 * and let some progress happen before we try again.
4079 * This function will sleep at least once waiting for new free space to
4080 * show up, and then it will check the block group free space numbers
4081 * for our min num_bytes. Another option is to have it go ahead
4082 * and look in the rbtree for a free extent of a given size, but this
4086 wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
4089 struct btrfs_caching_control *caching_ctl;
4092 caching_ctl = get_caching_control(cache);
4096 wait_event(caching_ctl->wait, block_group_cache_done(cache) ||
4097 (cache->free_space >= num_bytes));
4099 put_caching_control(caching_ctl);
4104 wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
4106 struct btrfs_caching_control *caching_ctl;
4109 caching_ctl = get_caching_control(cache);
4113 wait_event(caching_ctl->wait, block_group_cache_done(cache));
4115 put_caching_control(caching_ctl);
4119 enum btrfs_loop_type {
4120 LOOP_FIND_IDEAL = 0,
4121 LOOP_CACHING_NOWAIT = 1,
4122 LOOP_CACHING_WAIT = 2,
4123 LOOP_ALLOC_CHUNK = 3,
4124 LOOP_NO_EMPTY_SIZE = 4,
4128 * walks the btree of allocated extents and find a hole of a given size.
4129 * The key ins is changed to record the hole:
4130 * ins->objectid == block start
4131 * ins->flags = BTRFS_EXTENT_ITEM_KEY
4132 * ins->offset == number of blocks
4133 * Any available blocks before search_start are skipped.
4135 static noinline int find_free_extent(struct btrfs_trans_handle *trans,
4136 struct btrfs_root *orig_root,
4137 u64 num_bytes, u64 empty_size,
4138 u64 search_start, u64 search_end,
4139 u64 hint_byte, struct btrfs_key *ins,
4140 u64 exclude_start, u64 exclude_nr,
4144 struct btrfs_root *root = orig_root->fs_info->extent_root;
4145 struct btrfs_free_cluster *last_ptr = NULL;
4146 struct btrfs_block_group_cache *block_group = NULL;
4147 int empty_cluster = 2 * 1024 * 1024;
4148 int allowed_chunk_alloc = 0;
4149 int done_chunk_alloc = 0;
4150 struct btrfs_space_info *space_info;
4151 int last_ptr_loop = 0;
4153 bool found_uncached_bg = false;
4154 bool failed_cluster_refill = false;
4155 bool failed_alloc = false;
4156 u64 ideal_cache_percent = 0;
4157 u64 ideal_cache_offset = 0;
4159 WARN_ON(num_bytes < root->sectorsize);
4160 btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
4164 space_info = __find_space_info(root->fs_info, data);
4166 if (orig_root->ref_cows || empty_size)
4167 allowed_chunk_alloc = 1;
4169 if (data & BTRFS_BLOCK_GROUP_METADATA) {
4170 last_ptr = &root->fs_info->meta_alloc_cluster;
4171 if (!btrfs_test_opt(root, SSD))
4172 empty_cluster = 64 * 1024;
4175 if ((data & BTRFS_BLOCK_GROUP_DATA) && btrfs_test_opt(root, SSD)) {
4176 last_ptr = &root->fs_info->data_alloc_cluster;
4180 spin_lock(&last_ptr->lock);
4181 if (last_ptr->block_group)
4182 hint_byte = last_ptr->window_start;
4183 spin_unlock(&last_ptr->lock);
4186 search_start = max(search_start, first_logical_byte(root, 0));
4187 search_start = max(search_start, hint_byte);
4192 if (search_start == hint_byte) {
4194 block_group = btrfs_lookup_block_group(root->fs_info,
4197 * we don't want to use the block group if it doesn't match our
4198 * allocation bits, or if its not cached.
4200 * However if we are re-searching with an ideal block group
4201 * picked out then we don't care that the block group is cached.
4203 if (block_group && block_group_bits(block_group, data) &&
4204 (block_group->cached != BTRFS_CACHE_NO ||
4205 search_start == ideal_cache_offset)) {
4206 down_read(&space_info->groups_sem);
4207 if (list_empty(&block_group->list) ||
4210 * someone is removing this block group,
4211 * we can't jump into the have_block_group
4212 * target because our list pointers are not
4215 btrfs_put_block_group(block_group);
4216 up_read(&space_info->groups_sem);
4218 goto have_block_group;
4220 } else if (block_group) {
4221 btrfs_put_block_group(block_group);
4225 down_read(&space_info->groups_sem);
4226 list_for_each_entry(block_group, &space_info->block_groups, list) {
4230 atomic_inc(&block_group->count);
4231 search_start = block_group->key.objectid;
4234 if (unlikely(block_group->cached == BTRFS_CACHE_NO)) {
4237 free_percent = btrfs_block_group_used(&block_group->item);
4238 free_percent *= 100;
4239 free_percent = div64_u64(free_percent,
4240 block_group->key.offset);
4241 free_percent = 100 - free_percent;
4242 if (free_percent > ideal_cache_percent &&
4243 likely(!block_group->ro)) {
4244 ideal_cache_offset = block_group->key.objectid;
4245 ideal_cache_percent = free_percent;
4249 * We only want to start kthread caching if we are at
4250 * the point where we will wait for caching to make
4251 * progress, or if our ideal search is over and we've
4252 * found somebody to start caching.
4254 if (loop > LOOP_CACHING_NOWAIT ||
4255 (loop > LOOP_FIND_IDEAL &&
4256 atomic_read(&space_info->caching_threads) < 2)) {
4257 ret = cache_block_group(block_group);
4260 found_uncached_bg = true;
4263 * If loop is set for cached only, try the next block
4266 if (loop == LOOP_FIND_IDEAL)
4270 cached = block_group_cache_done(block_group);
4271 if (unlikely(!cached))
4272 found_uncached_bg = true;
4274 if (unlikely(block_group->ro))
4278 * Ok we want to try and use the cluster allocator, so lets look
4279 * there, unless we are on LOOP_NO_EMPTY_SIZE, since we will
4280 * have tried the cluster allocator plenty of times at this
4281 * point and not have found anything, so we are likely way too
4282 * fragmented for the clustering stuff to find anything, so lets
4283 * just skip it and let the allocator find whatever block it can
4286 if (last_ptr && loop < LOOP_NO_EMPTY_SIZE) {
4288 * the refill lock keeps out other
4289 * people trying to start a new cluster
4291 spin_lock(&last_ptr->refill_lock);
4292 if (last_ptr->block_group &&
4293 (last_ptr->block_group->ro ||
4294 !block_group_bits(last_ptr->block_group, data))) {
4296 goto refill_cluster;
4299 offset = btrfs_alloc_from_cluster(block_group, last_ptr,
4300 num_bytes, search_start);
4302 /* we have a block, we're done */
4303 spin_unlock(&last_ptr->refill_lock);
4307 spin_lock(&last_ptr->lock);
4309 * whoops, this cluster doesn't actually point to
4310 * this block group. Get a ref on the block
4311 * group is does point to and try again
4313 if (!last_ptr_loop && last_ptr->block_group &&
4314 last_ptr->block_group != block_group) {
4316 btrfs_put_block_group(block_group);
4317 block_group = last_ptr->block_group;
4318 atomic_inc(&block_group->count);
4319 spin_unlock(&last_ptr->lock);
4320 spin_unlock(&last_ptr->refill_lock);
4323 search_start = block_group->key.objectid;
4325 * we know this block group is properly
4326 * in the list because
4327 * btrfs_remove_block_group, drops the
4328 * cluster before it removes the block
4329 * group from the list
4331 goto have_block_group;
4333 spin_unlock(&last_ptr->lock);
4336 * this cluster didn't work out, free it and
4339 btrfs_return_cluster_to_free_space(NULL, last_ptr);
4343 /* allocate a cluster in this block group */
4344 ret = btrfs_find_space_cluster(trans, root,
4345 block_group, last_ptr,
4347 empty_cluster + empty_size);
4350 * now pull our allocation out of this
4353 offset = btrfs_alloc_from_cluster(block_group,
4354 last_ptr, num_bytes,
4357 /* we found one, proceed */
4358 spin_unlock(&last_ptr->refill_lock);
4361 } else if (!cached && loop > LOOP_CACHING_NOWAIT
4362 && !failed_cluster_refill) {
4363 spin_unlock(&last_ptr->refill_lock);
4365 failed_cluster_refill = true;
4366 wait_block_group_cache_progress(block_group,
4367 num_bytes + empty_cluster + empty_size);
4368 goto have_block_group;
4372 * at this point we either didn't find a cluster
4373 * or we weren't able to allocate a block from our
4374 * cluster. Free the cluster we've been trying
4375 * to use, and go to the next block group
4377 btrfs_return_cluster_to_free_space(NULL, last_ptr);
4378 spin_unlock(&last_ptr->refill_lock);
4382 offset = btrfs_find_space_for_alloc(block_group, search_start,
4383 num_bytes, empty_size);
4385 * If we didn't find a chunk, and we haven't failed on this
4386 * block group before, and this block group is in the middle of
4387 * caching and we are ok with waiting, then go ahead and wait
4388 * for progress to be made, and set failed_alloc to true.
4390 * If failed_alloc is true then we've already waited on this
4391 * block group once and should move on to the next block group.
4393 if (!offset && !failed_alloc && !cached &&
4394 loop > LOOP_CACHING_NOWAIT) {
4395 wait_block_group_cache_progress(block_group,
4396 num_bytes + empty_size);
4397 failed_alloc = true;
4398 goto have_block_group;
4399 } else if (!offset) {
4403 search_start = stripe_align(root, offset);
4404 /* move on to the next group */
4405 if (search_start + num_bytes >= search_end) {
4406 btrfs_add_free_space(block_group, offset, num_bytes);
4410 /* move on to the next group */
4411 if (search_start + num_bytes >
4412 block_group->key.objectid + block_group->key.offset) {
4413 btrfs_add_free_space(block_group, offset, num_bytes);
4417 if (exclude_nr > 0 &&
4418 (search_start + num_bytes > exclude_start &&
4419 search_start < exclude_start + exclude_nr)) {
4420 search_start = exclude_start + exclude_nr;
4422 btrfs_add_free_space(block_group, offset, num_bytes);
4424 * if search_start is still in this block group
4425 * then we just re-search this block group
4427 if (search_start >= block_group->key.objectid &&
4428 search_start < (block_group->key.objectid +
4429 block_group->key.offset))
4430 goto have_block_group;
4434 ins->objectid = search_start;
4435 ins->offset = num_bytes;
4437 if (offset < search_start)
4438 btrfs_add_free_space(block_group, offset,
4439 search_start - offset);
4440 BUG_ON(offset > search_start);
4442 update_reserved_extents(block_group, num_bytes, 1);
4444 /* we are all good, lets return */
4447 failed_cluster_refill = false;
4448 failed_alloc = false;
4449 btrfs_put_block_group(block_group);
4451 up_read(&space_info->groups_sem);
4453 /* LOOP_FIND_IDEAL, only search caching/cached bg's, and don't wait for
4454 * for them to make caching progress. Also
4455 * determine the best possible bg to cache
4456 * LOOP_CACHING_NOWAIT, search partially cached block groups, kicking
4457 * caching kthreads as we move along
4458 * LOOP_CACHING_WAIT, search everything, and wait if our bg is caching
4459 * LOOP_ALLOC_CHUNK, force a chunk allocation and try again
4460 * LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try
4463 if (!ins->objectid && loop < LOOP_NO_EMPTY_SIZE &&
4464 (found_uncached_bg || empty_size || empty_cluster ||
4465 allowed_chunk_alloc)) {
4466 if (loop == LOOP_FIND_IDEAL && found_uncached_bg) {
4467 found_uncached_bg = false;
4469 if (!ideal_cache_percent &&
4470 atomic_read(&space_info->caching_threads))
4474 * 1 of the following 2 things have happened so far
4476 * 1) We found an ideal block group for caching that
4477 * is mostly full and will cache quickly, so we might
4478 * as well wait for it.
4480 * 2) We searched for cached only and we didn't find
4481 * anything, and we didn't start any caching kthreads
4482 * either, so chances are we will loop through and
4483 * start a couple caching kthreads, and then come back
4484 * around and just wait for them. This will be slower
4485 * because we will have 2 caching kthreads reading at
4486 * the same time when we could have just started one
4487 * and waited for it to get far enough to give us an
4488 * allocation, so go ahead and go to the wait caching
4491 loop = LOOP_CACHING_WAIT;
4492 search_start = ideal_cache_offset;
4493 ideal_cache_percent = 0;
4495 } else if (loop == LOOP_FIND_IDEAL) {
4497 * Didn't find a uncached bg, wait on anything we find
4500 loop = LOOP_CACHING_WAIT;
4504 if (loop < LOOP_CACHING_WAIT) {
4509 if (loop == LOOP_ALLOC_CHUNK) {
4514 if (allowed_chunk_alloc) {
4515 ret = do_chunk_alloc(trans, root, num_bytes +
4516 2 * 1024 * 1024, data, 1);
4517 allowed_chunk_alloc = 0;
4518 done_chunk_alloc = 1;
4519 } else if (!done_chunk_alloc) {
4520 space_info->force_alloc = 1;
4523 if (loop < LOOP_NO_EMPTY_SIZE) {
4528 } else if (!ins->objectid) {
4532 /* we found what we needed */
4533 if (ins->objectid) {
4534 if (!(data & BTRFS_BLOCK_GROUP_DATA))
4535 trans->block_group = block_group->key.objectid;
4537 btrfs_put_block_group(block_group);
4544 static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
4545 int dump_block_groups)
4547 struct btrfs_block_group_cache *cache;
4549 spin_lock(&info->lock);
4550 printk(KERN_INFO "space_info has %llu free, is %sfull\n",
4551 (unsigned long long)(info->total_bytes - info->bytes_used -
4552 info->bytes_pinned - info->bytes_reserved -
4554 (info->full) ? "" : "not ");
4555 printk(KERN_INFO "space_info total=%llu, pinned=%llu, delalloc=%llu,"
4556 " may_use=%llu, used=%llu, root=%llu, super=%llu, reserved=%llu"
4558 (unsigned long long)info->total_bytes,
4559 (unsigned long long)info->bytes_pinned,
4560 (unsigned long long)info->bytes_delalloc,
4561 (unsigned long long)info->bytes_may_use,
4562 (unsigned long long)info->bytes_used,
4563 (unsigned long long)info->bytes_root,
4564 (unsigned long long)info->bytes_super,
4565 (unsigned long long)info->bytes_reserved);
4566 spin_unlock(&info->lock);
4568 if (!dump_block_groups)
4571 down_read(&info->groups_sem);
4572 list_for_each_entry(cache, &info->block_groups, list) {
4573 spin_lock(&cache->lock);
4574 printk(KERN_INFO "block group %llu has %llu bytes, %llu used "
4575 "%llu pinned %llu reserved\n",
4576 (unsigned long long)cache->key.objectid,
4577 (unsigned long long)cache->key.offset,
4578 (unsigned long long)btrfs_block_group_used(&cache->item),
4579 (unsigned long long)cache->pinned,
4580 (unsigned long long)cache->reserved);
4581 btrfs_dump_free_space(cache, bytes);
4582 spin_unlock(&cache->lock);
4584 up_read(&info->groups_sem);
4587 int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
4588 struct btrfs_root *root,
4589 u64 num_bytes, u64 min_alloc_size,
4590 u64 empty_size, u64 hint_byte,
4591 u64 search_end, struct btrfs_key *ins,
4595 u64 search_start = 0;
4597 data = btrfs_get_alloc_profile(root, data);
4600 * the only place that sets empty_size is btrfs_realloc_node, which
4601 * is not called recursively on allocations
4603 if (empty_size || root->ref_cows)
4604 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
4605 num_bytes + 2 * 1024 * 1024, data, 0);
4607 WARN_ON(num_bytes < root->sectorsize);
4608 ret = find_free_extent(trans, root, num_bytes, empty_size,
4609 search_start, search_end, hint_byte, ins,
4610 trans->alloc_exclude_start,
4611 trans->alloc_exclude_nr, data);
4613 if (ret == -ENOSPC && num_bytes > min_alloc_size) {
4614 num_bytes = num_bytes >> 1;
4615 num_bytes = num_bytes & ~(root->sectorsize - 1);
4616 num_bytes = max(num_bytes, min_alloc_size);
4617 do_chunk_alloc(trans, root->fs_info->extent_root,
4618 num_bytes, data, 1);
4621 if (ret == -ENOSPC) {
4622 struct btrfs_space_info *sinfo;
4624 sinfo = __find_space_info(root->fs_info, data);
4625 printk(KERN_ERR "btrfs allocation failed flags %llu, "
4626 "wanted %llu\n", (unsigned long long)data,
4627 (unsigned long long)num_bytes);
4628 dump_space_info(sinfo, num_bytes, 1);
4634 int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len)
4636 struct btrfs_block_group_cache *cache;
4639 cache = btrfs_lookup_block_group(root->fs_info, start);
4641 printk(KERN_ERR "Unable to find block group for %llu\n",
4642 (unsigned long long)start);
4646 ret = btrfs_discard_extent(root, start, len);
4648 btrfs_add_free_space(cache, start, len);
4649 update_reserved_extents(cache, len, 0);
4650 btrfs_put_block_group(cache);
4655 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
4656 struct btrfs_root *root,
4657 u64 parent, u64 root_objectid,
4658 u64 flags, u64 owner, u64 offset,
4659 struct btrfs_key *ins, int ref_mod)
4662 struct btrfs_fs_info *fs_info = root->fs_info;
4663 struct btrfs_extent_item *extent_item;
4664 struct btrfs_extent_inline_ref *iref;
4665 struct btrfs_path *path;
4666 struct extent_buffer *leaf;
4671 type = BTRFS_SHARED_DATA_REF_KEY;
4673 type = BTRFS_EXTENT_DATA_REF_KEY;
4675 size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type);
4677 path = btrfs_alloc_path();
4680 path->leave_spinning = 1;
4681 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
4685 leaf = path->nodes[0];
4686 extent_item = btrfs_item_ptr(leaf, path->slots[0],
4687 struct btrfs_extent_item);
4688 btrfs_set_extent_refs(leaf, extent_item, ref_mod);
4689 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
4690 btrfs_set_extent_flags(leaf, extent_item,
4691 flags | BTRFS_EXTENT_FLAG_DATA);
4693 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
4694 btrfs_set_extent_inline_ref_type(leaf, iref, type);
4696 struct btrfs_shared_data_ref *ref;
4697 ref = (struct btrfs_shared_data_ref *)(iref + 1);
4698 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
4699 btrfs_set_shared_data_ref_count(leaf, ref, ref_mod);
4701 struct btrfs_extent_data_ref *ref;
4702 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
4703 btrfs_set_extent_data_ref_root(leaf, ref, root_objectid);
4704 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
4705 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
4706 btrfs_set_extent_data_ref_count(leaf, ref, ref_mod);
4709 btrfs_mark_buffer_dirty(path->nodes[0]);
4710 btrfs_free_path(path);
4712 ret = update_block_group(trans, root, ins->objectid, ins->offset,
4715 printk(KERN_ERR "btrfs update block group failed for %llu "
4716 "%llu\n", (unsigned long long)ins->objectid,
4717 (unsigned long long)ins->offset);
4723 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
4724 struct btrfs_root *root,
4725 u64 parent, u64 root_objectid,
4726 u64 flags, struct btrfs_disk_key *key,
4727 int level, struct btrfs_key *ins)
4730 struct btrfs_fs_info *fs_info = root->fs_info;
4731 struct btrfs_extent_item *extent_item;
4732 struct btrfs_tree_block_info *block_info;
4733 struct btrfs_extent_inline_ref *iref;
4734 struct btrfs_path *path;
4735 struct extent_buffer *leaf;
4736 u32 size = sizeof(*extent_item) + sizeof(*block_info) + sizeof(*iref);
4738 path = btrfs_alloc_path();
4741 path->leave_spinning = 1;
4742 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
4746 leaf = path->nodes[0];
4747 extent_item = btrfs_item_ptr(leaf, path->slots[0],
4748 struct btrfs_extent_item);
4749 btrfs_set_extent_refs(leaf, extent_item, 1);
4750 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
4751 btrfs_set_extent_flags(leaf, extent_item,
4752 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
4753 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
4755 btrfs_set_tree_block_key(leaf, block_info, key);
4756 btrfs_set_tree_block_level(leaf, block_info, level);
4758 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
4760 BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF));
4761 btrfs_set_extent_inline_ref_type(leaf, iref,
4762 BTRFS_SHARED_BLOCK_REF_KEY);
4763 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
4765 btrfs_set_extent_inline_ref_type(leaf, iref,
4766 BTRFS_TREE_BLOCK_REF_KEY);
4767 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
4770 btrfs_mark_buffer_dirty(leaf);
4771 btrfs_free_path(path);
4773 ret = update_block_group(trans, root, ins->objectid, ins->offset,
4776 printk(KERN_ERR "btrfs update block group failed for %llu "
4777 "%llu\n", (unsigned long long)ins->objectid,
4778 (unsigned long long)ins->offset);
4784 int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
4785 struct btrfs_root *root,
4786 u64 root_objectid, u64 owner,
4787 u64 offset, struct btrfs_key *ins)
4791 BUG_ON(root_objectid == BTRFS_TREE_LOG_OBJECTID);
4793 ret = btrfs_add_delayed_data_ref(trans, ins->objectid, ins->offset,
4794 0, root_objectid, owner, offset,
4795 BTRFS_ADD_DELAYED_EXTENT, NULL);
4800 * this is used by the tree logging recovery code. It records that
4801 * an extent has been allocated and makes sure to clear the free
4802 * space cache bits as well
4804 int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
4805 struct btrfs_root *root,
4806 u64 root_objectid, u64 owner, u64 offset,
4807 struct btrfs_key *ins)
4810 struct btrfs_block_group_cache *block_group;
4811 struct btrfs_caching_control *caching_ctl;
4812 u64 start = ins->objectid;
4813 u64 num_bytes = ins->offset;
4815 block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
4816 cache_block_group(block_group);
4817 caching_ctl = get_caching_control(block_group);
4820 BUG_ON(!block_group_cache_done(block_group));
4821 ret = btrfs_remove_free_space(block_group, start, num_bytes);
4824 mutex_lock(&caching_ctl->mutex);
4826 if (start >= caching_ctl->progress) {
4827 ret = add_excluded_extent(root, start, num_bytes);
4829 } else if (start + num_bytes <= caching_ctl->progress) {
4830 ret = btrfs_remove_free_space(block_group,
4834 num_bytes = caching_ctl->progress - start;
4835 ret = btrfs_remove_free_space(block_group,
4839 start = caching_ctl->progress;
4840 num_bytes = ins->objectid + ins->offset -
4841 caching_ctl->progress;
4842 ret = add_excluded_extent(root, start, num_bytes);
4846 mutex_unlock(&caching_ctl->mutex);
4847 put_caching_control(caching_ctl);
4850 update_reserved_extents(block_group, ins->offset, 1);
4851 btrfs_put_block_group(block_group);
4852 ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,
4853 0, owner, offset, ins, 1);
4858 * finds a free extent and does all the dirty work required for allocation
4859 * returns the key for the extent through ins, and a tree buffer for
4860 * the first block of the extent through buf.
4862 * returns 0 if everything worked, non-zero otherwise.
4864 static int alloc_tree_block(struct btrfs_trans_handle *trans,
4865 struct btrfs_root *root,
4866 u64 num_bytes, u64 parent, u64 root_objectid,
4867 struct btrfs_disk_key *key, int level,
4868 u64 empty_size, u64 hint_byte, u64 search_end,
4869 struct btrfs_key *ins)
4874 ret = btrfs_reserve_extent(trans, root, num_bytes, num_bytes,
4875 empty_size, hint_byte, search_end,
4880 if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
4882 parent = ins->objectid;
4883 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
4887 if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
4888 struct btrfs_delayed_extent_op *extent_op;
4889 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
4892 memcpy(&extent_op->key, key, sizeof(extent_op->key));
4894 memset(&extent_op->key, 0, sizeof(extent_op->key));
4895 extent_op->flags_to_set = flags;
4896 extent_op->update_key = 1;
4897 extent_op->update_flags = 1;
4898 extent_op->is_data = 0;
4900 ret = btrfs_add_delayed_tree_ref(trans, ins->objectid,
4901 ins->offset, parent, root_objectid,
4902 level, BTRFS_ADD_DELAYED_EXTENT,
4907 if (root_objectid == root->root_key.objectid) {
4909 spin_lock(&root->node_lock);
4910 used = btrfs_root_used(&root->root_item) + num_bytes;
4911 btrfs_set_root_used(&root->root_item, used);
4912 spin_unlock(&root->node_lock);
4917 struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
4918 struct btrfs_root *root,
4919 u64 bytenr, u32 blocksize,
4922 struct extent_buffer *buf;
4924 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
4926 return ERR_PTR(-ENOMEM);
4927 btrfs_set_header_generation(buf, trans->transid);
4928 btrfs_set_buffer_lockdep_class(buf, level);
4929 btrfs_tree_lock(buf);
4930 clean_tree_block(trans, root, buf);
4932 btrfs_set_lock_blocking(buf);
4933 btrfs_set_buffer_uptodate(buf);
4935 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
4937 * we allow two log transactions at a time, use different
4938 * EXENT bit to differentiate dirty pages.
4940 if (root->log_transid % 2 == 0)
4941 set_extent_dirty(&root->dirty_log_pages, buf->start,
4942 buf->start + buf->len - 1, GFP_NOFS);
4944 set_extent_new(&root->dirty_log_pages, buf->start,
4945 buf->start + buf->len - 1, GFP_NOFS);
4947 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
4948 buf->start + buf->len - 1, GFP_NOFS);
4950 trans->blocks_used++;
4951 /* this returns a buffer locked for blocking */
4956 * helper function to allocate a block for a given tree
4957 * returns the tree buffer or NULL.
4959 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
4960 struct btrfs_root *root, u32 blocksize,
4961 u64 parent, u64 root_objectid,
4962 struct btrfs_disk_key *key, int level,
4963 u64 hint, u64 empty_size)
4965 struct btrfs_key ins;
4967 struct extent_buffer *buf;
4969 ret = alloc_tree_block(trans, root, blocksize, parent, root_objectid,
4970 key, level, empty_size, hint, (u64)-1, &ins);
4973 return ERR_PTR(ret);
4976 buf = btrfs_init_new_buffer(trans, root, ins.objectid,
4981 struct walk_control {
4982 u64 refs[BTRFS_MAX_LEVEL];
4983 u64 flags[BTRFS_MAX_LEVEL];
4984 struct btrfs_key update_progress;
4994 #define DROP_REFERENCE 1
4995 #define UPDATE_BACKREF 2
4997 static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
4998 struct btrfs_root *root,
4999 struct walk_control *wc,
5000 struct btrfs_path *path)
5009 struct btrfs_key key;
5010 struct extent_buffer *eb;
5015 if (path->slots[wc->level] < wc->reada_slot) {
5016 wc->reada_count = wc->reada_count * 2 / 3;
5017 wc->reada_count = max(wc->reada_count, 2);
5019 wc->reada_count = wc->reada_count * 3 / 2;
5020 wc->reada_count = min_t(int, wc->reada_count,
5021 BTRFS_NODEPTRS_PER_BLOCK(root));
5024 eb = path->nodes[wc->level];
5025 nritems = btrfs_header_nritems(eb);
5026 blocksize = btrfs_level_size(root, wc->level - 1);
5028 for (slot = path->slots[wc->level]; slot < nritems; slot++) {
5029 if (nread >= wc->reada_count)
5033 bytenr = btrfs_node_blockptr(eb, slot);
5034 generation = btrfs_node_ptr_generation(eb, slot);
5036 if (slot == path->slots[wc->level])
5039 if (wc->stage == UPDATE_BACKREF &&
5040 generation <= root->root_key.offset)
5043 /* We don't lock the tree block, it's OK to be racy here */
5044 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
5049 if (wc->stage == DROP_REFERENCE) {
5053 if (wc->level == 1 &&
5054 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5056 if (!wc->update_ref ||
5057 generation <= root->root_key.offset)
5059 btrfs_node_key_to_cpu(eb, &key, slot);
5060 ret = btrfs_comp_cpu_keys(&key,
5061 &wc->update_progress);
5065 if (wc->level == 1 &&
5066 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5070 ret = readahead_tree_block(root, bytenr, blocksize,
5074 last = bytenr + blocksize;
5077 wc->reada_slot = slot;
5081 * hepler to process tree block while walking down the tree.
5083 * when wc->stage == UPDATE_BACKREF, this function updates
5084 * back refs for pointers in the block.
5086 * NOTE: return value 1 means we should stop walking down.
5088 static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
5089 struct btrfs_root *root,
5090 struct btrfs_path *path,
5091 struct walk_control *wc, int lookup_info)
5093 int level = wc->level;
5094 struct extent_buffer *eb = path->nodes[level];
5095 u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF;
5098 if (wc->stage == UPDATE_BACKREF &&
5099 btrfs_header_owner(eb) != root->root_key.objectid)
5103 * when reference count of tree block is 1, it won't increase
5104 * again. once full backref flag is set, we never clear it.
5107 ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
5108 (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag)))) {
5109 BUG_ON(!path->locks[level]);
5110 ret = btrfs_lookup_extent_info(trans, root,
5115 BUG_ON(wc->refs[level] == 0);
5118 if (wc->stage == DROP_REFERENCE) {
5119 if (wc->refs[level] > 1)
5122 if (path->locks[level] && !wc->keep_locks) {
5123 btrfs_tree_unlock(eb);
5124 path->locks[level] = 0;
5129 /* wc->stage == UPDATE_BACKREF */
5130 if (!(wc->flags[level] & flag)) {
5131 BUG_ON(!path->locks[level]);
5132 ret = btrfs_inc_ref(trans, root, eb, 1);
5134 ret = btrfs_dec_ref(trans, root, eb, 0);
5136 ret = btrfs_set_disk_extent_flags(trans, root, eb->start,
5139 wc->flags[level] |= flag;
5143 * the block is shared by multiple trees, so it's not good to
5144 * keep the tree lock
5146 if (path->locks[level] && level > 0) {
5147 btrfs_tree_unlock(eb);
5148 path->locks[level] = 0;
5154 * hepler to process tree block pointer.
5156 * when wc->stage == DROP_REFERENCE, this function checks
5157 * reference count of the block pointed to. if the block
5158 * is shared and we need update back refs for the subtree
5159 * rooted at the block, this function changes wc->stage to
5160 * UPDATE_BACKREF. if the block is shared and there is no
5161 * need to update back, this function drops the reference
5164 * NOTE: return value 1 means we should stop walking down.
5166 static noinline int do_walk_down(struct btrfs_trans_handle *trans,
5167 struct btrfs_root *root,
5168 struct btrfs_path *path,
5169 struct walk_control *wc, int *lookup_info)
5175 struct btrfs_key key;
5176 struct extent_buffer *next;
5177 int level = wc->level;
5181 generation = btrfs_node_ptr_generation(path->nodes[level],
5182 path->slots[level]);
5184 * if the lower level block was created before the snapshot
5185 * was created, we know there is no need to update back refs
5188 if (wc->stage == UPDATE_BACKREF &&
5189 generation <= root->root_key.offset) {
5194 bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]);
5195 blocksize = btrfs_level_size(root, level - 1);
5197 next = btrfs_find_tree_block(root, bytenr, blocksize);
5199 next = btrfs_find_create_tree_block(root, bytenr, blocksize);
5202 btrfs_tree_lock(next);
5203 btrfs_set_lock_blocking(next);
5205 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
5206 &wc->refs[level - 1],
5207 &wc->flags[level - 1]);
5209 BUG_ON(wc->refs[level - 1] == 0);
5212 if (wc->stage == DROP_REFERENCE) {
5213 if (wc->refs[level - 1] > 1) {
5215 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5218 if (!wc->update_ref ||
5219 generation <= root->root_key.offset)
5222 btrfs_node_key_to_cpu(path->nodes[level], &key,
5223 path->slots[level]);
5224 ret = btrfs_comp_cpu_keys(&key, &wc->update_progress);
5228 wc->stage = UPDATE_BACKREF;
5229 wc->shared_level = level - 1;
5233 (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
5237 if (!btrfs_buffer_uptodate(next, generation)) {
5238 btrfs_tree_unlock(next);
5239 free_extent_buffer(next);
5245 if (reada && level == 1)
5246 reada_walk_down(trans, root, wc, path);
5247 next = read_tree_block(root, bytenr, blocksize, generation);
5248 btrfs_tree_lock(next);
5249 btrfs_set_lock_blocking(next);
5253 BUG_ON(level != btrfs_header_level(next));
5254 path->nodes[level] = next;
5255 path->slots[level] = 0;
5256 path->locks[level] = 1;
5262 wc->refs[level - 1] = 0;
5263 wc->flags[level - 1] = 0;
5264 if (wc->stage == DROP_REFERENCE) {
5265 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
5266 parent = path->nodes[level]->start;
5268 BUG_ON(root->root_key.objectid !=
5269 btrfs_header_owner(path->nodes[level]));
5273 ret = btrfs_free_extent(trans, root, bytenr, blocksize, parent,
5274 root->root_key.objectid, level - 1, 0);
5277 btrfs_tree_unlock(next);
5278 free_extent_buffer(next);
5284 * hepler to process tree block while walking up the tree.
5286 * when wc->stage == DROP_REFERENCE, this function drops
5287 * reference count on the block.
5289 * when wc->stage == UPDATE_BACKREF, this function changes
5290 * wc->stage back to DROP_REFERENCE if we changed wc->stage
5291 * to UPDATE_BACKREF previously while processing the block.
5293 * NOTE: return value 1 means we should stop walking up.
5295 static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
5296 struct btrfs_root *root,
5297 struct btrfs_path *path,
5298 struct walk_control *wc)
5301 int level = wc->level;
5302 struct extent_buffer *eb = path->nodes[level];
5305 if (wc->stage == UPDATE_BACKREF) {
5306 BUG_ON(wc->shared_level < level);
5307 if (level < wc->shared_level)
5310 ret = find_next_key(path, level + 1, &wc->update_progress);
5314 wc->stage = DROP_REFERENCE;
5315 wc->shared_level = -1;
5316 path->slots[level] = 0;
5319 * check reference count again if the block isn't locked.
5320 * we should start walking down the tree again if reference
5323 if (!path->locks[level]) {
5325 btrfs_tree_lock(eb);
5326 btrfs_set_lock_blocking(eb);
5327 path->locks[level] = 1;
5329 ret = btrfs_lookup_extent_info(trans, root,
5334 BUG_ON(wc->refs[level] == 0);
5335 if (wc->refs[level] == 1) {
5336 btrfs_tree_unlock(eb);
5337 path->locks[level] = 0;
5343 /* wc->stage == DROP_REFERENCE */
5344 BUG_ON(wc->refs[level] > 1 && !path->locks[level]);
5346 if (wc->refs[level] == 1) {
5348 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
5349 ret = btrfs_dec_ref(trans, root, eb, 1);
5351 ret = btrfs_dec_ref(trans, root, eb, 0);
5354 /* make block locked assertion in clean_tree_block happy */
5355 if (!path->locks[level] &&
5356 btrfs_header_generation(eb) == trans->transid) {
5357 btrfs_tree_lock(eb);
5358 btrfs_set_lock_blocking(eb);
5359 path->locks[level] = 1;
5361 clean_tree_block(trans, root, eb);
5364 if (eb == root->node) {
5365 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
5368 BUG_ON(root->root_key.objectid !=
5369 btrfs_header_owner(eb));
5371 if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
5372 parent = path->nodes[level + 1]->start;
5374 BUG_ON(root->root_key.objectid !=
5375 btrfs_header_owner(path->nodes[level + 1]));
5378 ret = btrfs_free_extent(trans, root, eb->start, eb->len, parent,
5379 root->root_key.objectid, level, 0);
5382 wc->refs[level] = 0;
5383 wc->flags[level] = 0;
5387 static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
5388 struct btrfs_root *root,
5389 struct btrfs_path *path,
5390 struct walk_control *wc)
5392 int level = wc->level;
5393 int lookup_info = 1;
5396 while (level >= 0) {
5397 if (path->slots[level] >=
5398 btrfs_header_nritems(path->nodes[level]))
5401 ret = walk_down_proc(trans, root, path, wc, lookup_info);
5408 ret = do_walk_down(trans, root, path, wc, &lookup_info);
5410 path->slots[level]++;
5418 static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
5419 struct btrfs_root *root,
5420 struct btrfs_path *path,
5421 struct walk_control *wc, int max_level)
5423 int level = wc->level;
5426 path->slots[level] = btrfs_header_nritems(path->nodes[level]);
5427 while (level < max_level && path->nodes[level]) {
5429 if (path->slots[level] + 1 <
5430 btrfs_header_nritems(path->nodes[level])) {
5431 path->slots[level]++;
5434 ret = walk_up_proc(trans, root, path, wc);
5438 if (path->locks[level]) {
5439 btrfs_tree_unlock(path->nodes[level]);
5440 path->locks[level] = 0;
5442 free_extent_buffer(path->nodes[level]);
5443 path->nodes[level] = NULL;
5451 * drop a subvolume tree.
5453 * this function traverses the tree freeing any blocks that only
5454 * referenced by the tree.
5456 * when a shared tree block is found. this function decreases its
5457 * reference count by one. if update_ref is true, this function
5458 * also make sure backrefs for the shared block and all lower level
5459 * blocks are properly updated.
5461 int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref)
5463 struct btrfs_path *path;
5464 struct btrfs_trans_handle *trans;
5465 struct btrfs_root *tree_root = root->fs_info->tree_root;
5466 struct btrfs_root_item *root_item = &root->root_item;
5467 struct walk_control *wc;
5468 struct btrfs_key key;
5473 path = btrfs_alloc_path();
5476 wc = kzalloc(sizeof(*wc), GFP_NOFS);
5479 trans = btrfs_start_transaction(tree_root, 1);
5481 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
5482 level = btrfs_header_level(root->node);
5483 path->nodes[level] = btrfs_lock_root_node(root);
5484 btrfs_set_lock_blocking(path->nodes[level]);
5485 path->slots[level] = 0;
5486 path->locks[level] = 1;
5487 memset(&wc->update_progress, 0,
5488 sizeof(wc->update_progress));
5490 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
5491 memcpy(&wc->update_progress, &key,
5492 sizeof(wc->update_progress));
5494 level = root_item->drop_level;
5496 path->lowest_level = level;
5497 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5498 path->lowest_level = 0;
5506 * unlock our path, this is safe because only this
5507 * function is allowed to delete this snapshot
5509 btrfs_unlock_up_safe(path, 0);
5511 level = btrfs_header_level(root->node);
5513 btrfs_tree_lock(path->nodes[level]);
5514 btrfs_set_lock_blocking(path->nodes[level]);
5516 ret = btrfs_lookup_extent_info(trans, root,
5517 path->nodes[level]->start,
5518 path->nodes[level]->len,
5522 BUG_ON(wc->refs[level] == 0);
5524 if (level == root_item->drop_level)
5527 btrfs_tree_unlock(path->nodes[level]);
5528 WARN_ON(wc->refs[level] != 1);
5534 wc->shared_level = -1;
5535 wc->stage = DROP_REFERENCE;
5536 wc->update_ref = update_ref;
5538 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
5541 ret = walk_down_tree(trans, root, path, wc);
5547 ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL);
5554 BUG_ON(wc->stage != DROP_REFERENCE);
5558 if (wc->stage == DROP_REFERENCE) {
5560 btrfs_node_key(path->nodes[level],
5561 &root_item->drop_progress,
5562 path->slots[level]);
5563 root_item->drop_level = level;
5566 BUG_ON(wc->level == 0);
5567 if (trans->transaction->in_commit ||
5568 trans->transaction->delayed_refs.flushing) {
5569 ret = btrfs_update_root(trans, tree_root,
5574 btrfs_end_transaction(trans, tree_root);
5575 trans = btrfs_start_transaction(tree_root, 1);
5577 unsigned long update;
5578 update = trans->delayed_ref_updates;
5579 trans->delayed_ref_updates = 0;
5581 btrfs_run_delayed_refs(trans, tree_root,
5585 btrfs_release_path(root, path);
5588 ret = btrfs_del_root(trans, tree_root, &root->root_key);
5591 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
5592 ret = btrfs_find_last_root(tree_root, root->root_key.objectid,
5596 ret = btrfs_del_orphan_item(trans, tree_root,
5597 root->root_key.objectid);
5602 if (root->in_radix) {
5603 btrfs_free_fs_root(tree_root->fs_info, root);
5605 free_extent_buffer(root->node);
5606 free_extent_buffer(root->commit_root);
5610 btrfs_end_transaction(trans, tree_root);
5612 btrfs_free_path(path);
5617 * drop subtree rooted at tree block 'node'.
5619 * NOTE: this function will unlock and release tree block 'node'
5621 int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
5622 struct btrfs_root *root,
5623 struct extent_buffer *node,
5624 struct extent_buffer *parent)
5626 struct btrfs_path *path;
5627 struct walk_control *wc;
5633 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
5635 path = btrfs_alloc_path();
5638 wc = kzalloc(sizeof(*wc), GFP_NOFS);
5641 btrfs_assert_tree_locked(parent);
5642 parent_level = btrfs_header_level(parent);
5643 extent_buffer_get(parent);
5644 path->nodes[parent_level] = parent;
5645 path->slots[parent_level] = btrfs_header_nritems(parent);
5647 btrfs_assert_tree_locked(node);
5648 level = btrfs_header_level(node);
5649 path->nodes[level] = node;
5650 path->slots[level] = 0;
5651 path->locks[level] = 1;
5653 wc->refs[parent_level] = 1;
5654 wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF;
5656 wc->shared_level = -1;
5657 wc->stage = DROP_REFERENCE;
5660 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
5663 wret = walk_down_tree(trans, root, path, wc);
5669 wret = walk_up_tree(trans, root, path, wc, parent_level);
5677 btrfs_free_path(path);
5682 static unsigned long calc_ra(unsigned long start, unsigned long last,
5685 return min(last, start + nr - 1);
5688 static noinline int relocate_inode_pages(struct inode *inode, u64 start,
5693 unsigned long first_index;
5694 unsigned long last_index;
5697 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
5698 struct file_ra_state *ra;
5699 struct btrfs_ordered_extent *ordered;
5700 unsigned int total_read = 0;
5701 unsigned int total_dirty = 0;
5704 ra = kzalloc(sizeof(*ra), GFP_NOFS);
5706 mutex_lock(&inode->i_mutex);
5707 first_index = start >> PAGE_CACHE_SHIFT;
5708 last_index = (start + len - 1) >> PAGE_CACHE_SHIFT;
5710 /* make sure the dirty trick played by the caller work */
5711 ret = invalidate_inode_pages2_range(inode->i_mapping,
5712 first_index, last_index);
5716 file_ra_state_init(ra, inode->i_mapping);
5718 for (i = first_index ; i <= last_index; i++) {
5719 if (total_read % ra->ra_pages == 0) {
5720 btrfs_force_ra(inode->i_mapping, ra, NULL, i,
5721 calc_ra(i, last_index, ra->ra_pages));
5725 if (((u64)i << PAGE_CACHE_SHIFT) > i_size_read(inode))
5727 page = grab_cache_page(inode->i_mapping, i);
5732 if (!PageUptodate(page)) {
5733 btrfs_readpage(NULL, page);
5735 if (!PageUptodate(page)) {
5737 page_cache_release(page);
5742 wait_on_page_writeback(page);
5744 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
5745 page_end = page_start + PAGE_CACHE_SIZE - 1;
5746 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
5748 ordered = btrfs_lookup_ordered_extent(inode, page_start);
5750 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
5752 page_cache_release(page);
5753 btrfs_start_ordered_extent(inode, ordered, 1);
5754 btrfs_put_ordered_extent(ordered);
5757 set_page_extent_mapped(page);
5759 if (i == first_index)
5760 set_extent_bits(io_tree, page_start, page_end,
5761 EXTENT_BOUNDARY, GFP_NOFS);
5762 btrfs_set_extent_delalloc(inode, page_start, page_end);
5764 set_page_dirty(page);
5767 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
5769 page_cache_release(page);
5774 mutex_unlock(&inode->i_mutex);
5775 balance_dirty_pages_ratelimited_nr(inode->i_mapping, total_dirty);
5779 static noinline int relocate_data_extent(struct inode *reloc_inode,
5780 struct btrfs_key *extent_key,
5783 struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
5784 struct extent_map_tree *em_tree = &BTRFS_I(reloc_inode)->extent_tree;
5785 struct extent_map *em;
5786 u64 start = extent_key->objectid - offset;
5787 u64 end = start + extent_key->offset - 1;
5789 em = alloc_extent_map(GFP_NOFS);
5790 BUG_ON(!em || IS_ERR(em));
5793 em->len = extent_key->offset;
5794 em->block_len = extent_key->offset;
5795 em->block_start = extent_key->objectid;
5796 em->bdev = root->fs_info->fs_devices->latest_bdev;
5797 set_bit(EXTENT_FLAG_PINNED, &em->flags);
5799 /* setup extent map to cheat btrfs_readpage */
5800 lock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
5803 write_lock(&em_tree->lock);
5804 ret = add_extent_mapping(em_tree, em);
5805 write_unlock(&em_tree->lock);
5806 if (ret != -EEXIST) {
5807 free_extent_map(em);
5810 btrfs_drop_extent_cache(reloc_inode, start, end, 0);
5812 unlock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
5814 return relocate_inode_pages(reloc_inode, start, extent_key->offset);
5817 struct btrfs_ref_path {
5819 u64 nodes[BTRFS_MAX_LEVEL];
5821 u64 root_generation;
5828 struct btrfs_key node_keys[BTRFS_MAX_LEVEL];
5829 u64 new_nodes[BTRFS_MAX_LEVEL];
5832 struct disk_extent {
5843 static int is_cowonly_root(u64 root_objectid)
5845 if (root_objectid == BTRFS_ROOT_TREE_OBJECTID ||
5846 root_objectid == BTRFS_EXTENT_TREE_OBJECTID ||
5847 root_objectid == BTRFS_CHUNK_TREE_OBJECTID ||
5848 root_objectid == BTRFS_DEV_TREE_OBJECTID ||
5849 root_objectid == BTRFS_TREE_LOG_OBJECTID ||
5850 root_objectid == BTRFS_CSUM_TREE_OBJECTID)
5855 static noinline int __next_ref_path(struct btrfs_trans_handle *trans,
5856 struct btrfs_root *extent_root,
5857 struct btrfs_ref_path *ref_path,
5860 struct extent_buffer *leaf;
5861 struct btrfs_path *path;
5862 struct btrfs_extent_ref *ref;
5863 struct btrfs_key key;
5864 struct btrfs_key found_key;
5870 path = btrfs_alloc_path();
5875 ref_path->lowest_level = -1;
5876 ref_path->current_level = -1;
5877 ref_path->shared_level = -1;
5881 level = ref_path->current_level - 1;
5882 while (level >= -1) {
5884 if (level < ref_path->lowest_level)
5888 bytenr = ref_path->nodes[level];
5890 bytenr = ref_path->extent_start;
5891 BUG_ON(bytenr == 0);
5893 parent = ref_path->nodes[level + 1];
5894 ref_path->nodes[level + 1] = 0;
5895 ref_path->current_level = level;
5896 BUG_ON(parent == 0);
5898 key.objectid = bytenr;
5899 key.offset = parent + 1;
5900 key.type = BTRFS_EXTENT_REF_KEY;
5902 ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0);
5907 leaf = path->nodes[0];
5908 nritems = btrfs_header_nritems(leaf);
5909 if (path->slots[0] >= nritems) {
5910 ret = btrfs_next_leaf(extent_root, path);
5915 leaf = path->nodes[0];
5918 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5919 if (found_key.objectid == bytenr &&
5920 found_key.type == BTRFS_EXTENT_REF_KEY) {
5921 if (level < ref_path->shared_level)
5922 ref_path->shared_level = level;
5927 btrfs_release_path(extent_root, path);
5930 /* reached lowest level */
5934 level = ref_path->current_level;
5935 while (level < BTRFS_MAX_LEVEL - 1) {
5939 bytenr = ref_path->nodes[level];
5941 bytenr = ref_path->extent_start;
5943 BUG_ON(bytenr == 0);
5945 key.objectid = bytenr;
5947 key.type = BTRFS_EXTENT_REF_KEY;
5949 ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0);
5953 leaf = path->nodes[0];
5954 nritems = btrfs_header_nritems(leaf);
5955 if (path->slots[0] >= nritems) {
5956 ret = btrfs_next_leaf(extent_root, path);
5960 /* the extent was freed by someone */
5961 if (ref_path->lowest_level == level)
5963 btrfs_release_path(extent_root, path);
5966 leaf = path->nodes[0];
5969 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5970 if (found_key.objectid != bytenr ||
5971 found_key.type != BTRFS_EXTENT_REF_KEY) {
5972 /* the extent was freed by someone */
5973 if (ref_path->lowest_level == level) {
5977 btrfs_release_path(extent_root, path);
5981 ref = btrfs_item_ptr(leaf, path->slots[0],
5982 struct btrfs_extent_ref);
5983 ref_objectid = btrfs_ref_objectid(leaf, ref);
5984 if (ref_objectid < BTRFS_FIRST_FREE_OBJECTID) {
5986 level = (int)ref_objectid;
5987 BUG_ON(level >= BTRFS_MAX_LEVEL);
5988 ref_path->lowest_level = level;
5989 ref_path->current_level = level;
5990 ref_path->nodes[level] = bytenr;
5992 WARN_ON(ref_objectid != level);
5995 WARN_ON(level != -1);
5999 if (ref_path->lowest_level == level) {
6000 ref_path->owner_objectid = ref_objectid;
6001 ref_path->num_refs = btrfs_ref_num_refs(leaf, ref);
6005 * the block is tree root or the block isn't in reference
6008 if (found_key.objectid == found_key.offset ||
6009 is_cowonly_root(btrfs_ref_root(leaf, ref))) {
6010 ref_path->root_objectid = btrfs_ref_root(leaf, ref);
6011 ref_path->root_generation =
6012 btrfs_ref_generation(leaf, ref);
6014 /* special reference from the tree log */
6015 ref_path->nodes[0] = found_key.offset;
6016 ref_path->current_level = 0;
6023 BUG_ON(ref_path->nodes[level] != 0);
6024 ref_path->nodes[level] = found_key.offset;
6025 ref_path->current_level = level;
6028 * the reference was created in the running transaction,
6029 * no need to continue walking up.
6031 if (btrfs_ref_generation(leaf, ref) == trans->transid) {
6032 ref_path->root_objectid = btrfs_ref_root(leaf, ref);
6033 ref_path->root_generation =
6034 btrfs_ref_generation(leaf, ref);
6039 btrfs_release_path(extent_root, path);
6042 /* reached max tree level, but no tree root found. */
6045 btrfs_free_path(path);
6049 static int btrfs_first_ref_path(struct btrfs_trans_handle *trans,
6050 struct btrfs_root *extent_root,
6051 struct btrfs_ref_path *ref_path,
6054 memset(ref_path, 0, sizeof(*ref_path));
6055 ref_path->extent_start = extent_start;
6057 return __next_ref_path(trans, extent_root, ref_path, 1);
6060 static int btrfs_next_ref_path(struct btrfs_trans_handle *trans,
6061 struct btrfs_root *extent_root,
6062 struct btrfs_ref_path *ref_path)
6064 return __next_ref_path(trans, extent_root, ref_path, 0);
6067 static noinline int get_new_locations(struct inode *reloc_inode,
6068 struct btrfs_key *extent_key,
6069 u64 offset, int no_fragment,
6070 struct disk_extent **extents,
6073 struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
6074 struct btrfs_path *path;
6075 struct btrfs_file_extent_item *fi;
6076 struct extent_buffer *leaf;
6077 struct disk_extent *exts = *extents;
6078 struct btrfs_key found_key;
6083 int max = *nr_extents;
6086 WARN_ON(!no_fragment && *extents);
6089 exts = kmalloc(sizeof(*exts) * max, GFP_NOFS);
6094 path = btrfs_alloc_path();
6097 cur_pos = extent_key->objectid - offset;
6098 last_byte = extent_key->objectid + extent_key->offset;
6099 ret = btrfs_lookup_file_extent(NULL, root, path, reloc_inode->i_ino,
6109 leaf = path->nodes[0];
6110 nritems = btrfs_header_nritems(leaf);
6111 if (path->slots[0] >= nritems) {
6112 ret = btrfs_next_leaf(root, path);
6117 leaf = path->nodes[0];
6120 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6121 if (found_key.offset != cur_pos ||
6122 found_key.type != BTRFS_EXTENT_DATA_KEY ||
6123 found_key.objectid != reloc_inode->i_ino)
6126 fi = btrfs_item_ptr(leaf, path->slots[0],
6127 struct btrfs_file_extent_item);
6128 if (btrfs_file_extent_type(leaf, fi) !=
6129 BTRFS_FILE_EXTENT_REG ||
6130 btrfs_file_extent_disk_bytenr(leaf, fi) == 0)
6134 struct disk_extent *old = exts;
6136 exts = kzalloc(sizeof(*exts) * max, GFP_NOFS);
6137 memcpy(exts, old, sizeof(*exts) * nr);
6138 if (old != *extents)
6142 exts[nr].disk_bytenr =
6143 btrfs_file_extent_disk_bytenr(leaf, fi);
6144 exts[nr].disk_num_bytes =
6145 btrfs_file_extent_disk_num_bytes(leaf, fi);
6146 exts[nr].offset = btrfs_file_extent_offset(leaf, fi);
6147 exts[nr].num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
6148 exts[nr].ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
6149 exts[nr].compression = btrfs_file_extent_compression(leaf, fi);
6150 exts[nr].encryption = btrfs_file_extent_encryption(leaf, fi);
6151 exts[nr].other_encoding = btrfs_file_extent_other_encoding(leaf,
6153 BUG_ON(exts[nr].offset > 0);
6154 BUG_ON(exts[nr].compression || exts[nr].encryption);
6155 BUG_ON(exts[nr].num_bytes != exts[nr].disk_num_bytes);
6157 cur_pos += exts[nr].num_bytes;
6160 if (cur_pos + offset >= last_byte)
6170 BUG_ON(cur_pos + offset > last_byte);
6171 if (cur_pos + offset < last_byte) {
6177 btrfs_free_path(path);
6179 if (exts != *extents)
6188 static noinline int replace_one_extent(struct btrfs_trans_handle *trans,
6189 struct btrfs_root *root,
6190 struct btrfs_path *path,
6191 struct btrfs_key *extent_key,
6192 struct btrfs_key *leaf_key,
6193 struct btrfs_ref_path *ref_path,
6194 struct disk_extent *new_extents,
6197 struct extent_buffer *leaf;
6198 struct btrfs_file_extent_item *fi;
6199 struct inode *inode = NULL;
6200 struct btrfs_key key;
6205 u64 search_end = (u64)-1;
6208 int extent_locked = 0;
6212 memcpy(&key, leaf_key, sizeof(key));
6213 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) {
6214 if (key.objectid < ref_path->owner_objectid ||
6215 (key.objectid == ref_path->owner_objectid &&
6216 key.type < BTRFS_EXTENT_DATA_KEY)) {
6217 key.objectid = ref_path->owner_objectid;
6218 key.type = BTRFS_EXTENT_DATA_KEY;
6224 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
6228 leaf = path->nodes[0];
6229 nritems = btrfs_header_nritems(leaf);
6231 if (extent_locked && ret > 0) {
6233 * the file extent item was modified by someone
6234 * before the extent got locked.
6236 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
6237 lock_end, GFP_NOFS);
6241 if (path->slots[0] >= nritems) {
6242 if (++nr_scaned > 2)
6245 BUG_ON(extent_locked);
6246 ret = btrfs_next_leaf(root, path);
6251 leaf = path->nodes[0];
6252 nritems = btrfs_header_nritems(leaf);
6255 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
6257 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) {
6258 if ((key.objectid > ref_path->owner_objectid) ||
6259 (key.objectid == ref_path->owner_objectid &&
6260 key.type > BTRFS_EXTENT_DATA_KEY) ||
6261 key.offset >= search_end)
6265 if (inode && key.objectid != inode->i_ino) {
6266 BUG_ON(extent_locked);
6267 btrfs_release_path(root, path);
6268 mutex_unlock(&inode->i_mutex);
6274 if (key.type != BTRFS_EXTENT_DATA_KEY) {
6279 fi = btrfs_item_ptr(leaf, path->slots[0],
6280 struct btrfs_file_extent_item);
6281 extent_type = btrfs_file_extent_type(leaf, fi);
6282 if ((extent_type != BTRFS_FILE_EXTENT_REG &&
6283 extent_type != BTRFS_FILE_EXTENT_PREALLOC) ||
6284 (btrfs_file_extent_disk_bytenr(leaf, fi) !=
6285 extent_key->objectid)) {
6291 num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
6292 ext_offset = btrfs_file_extent_offset(leaf, fi);
6294 if (search_end == (u64)-1) {
6295 search_end = key.offset - ext_offset +
6296 btrfs_file_extent_ram_bytes(leaf, fi);
6299 if (!extent_locked) {
6300 lock_start = key.offset;
6301 lock_end = lock_start + num_bytes - 1;
6303 if (lock_start > key.offset ||
6304 lock_end + 1 < key.offset + num_bytes) {
6305 unlock_extent(&BTRFS_I(inode)->io_tree,
6306 lock_start, lock_end, GFP_NOFS);
6312 btrfs_release_path(root, path);
6314 inode = btrfs_iget_locked(root->fs_info->sb,
6315 key.objectid, root);
6316 if (inode->i_state & I_NEW) {
6317 BTRFS_I(inode)->root = root;
6318 BTRFS_I(inode)->location.objectid =
6320 BTRFS_I(inode)->location.type =
6321 BTRFS_INODE_ITEM_KEY;
6322 BTRFS_I(inode)->location.offset = 0;
6323 btrfs_read_locked_inode(inode);
6324 unlock_new_inode(inode);
6327 * some code call btrfs_commit_transaction while
6328 * holding the i_mutex, so we can't use mutex_lock
6331 if (is_bad_inode(inode) ||
6332 !mutex_trylock(&inode->i_mutex)) {
6335 key.offset = (u64)-1;
6340 if (!extent_locked) {
6341 struct btrfs_ordered_extent *ordered;
6343 btrfs_release_path(root, path);
6345 lock_extent(&BTRFS_I(inode)->io_tree, lock_start,
6346 lock_end, GFP_NOFS);
6347 ordered = btrfs_lookup_first_ordered_extent(inode,
6350 ordered->file_offset <= lock_end &&
6351 ordered->file_offset + ordered->len > lock_start) {
6352 unlock_extent(&BTRFS_I(inode)->io_tree,
6353 lock_start, lock_end, GFP_NOFS);
6354 btrfs_start_ordered_extent(inode, ordered, 1);
6355 btrfs_put_ordered_extent(ordered);
6356 key.offset += num_bytes;
6360 btrfs_put_ordered_extent(ordered);
6366 if (nr_extents == 1) {
6367 /* update extent pointer in place */
6368 btrfs_set_file_extent_disk_bytenr(leaf, fi,
6369 new_extents[0].disk_bytenr);
6370 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
6371 new_extents[0].disk_num_bytes);
6372 btrfs_mark_buffer_dirty(leaf);
6374 btrfs_drop_extent_cache(inode, key.offset,
6375 key.offset + num_bytes - 1, 0);
6377 ret = btrfs_inc_extent_ref(trans, root,
6378 new_extents[0].disk_bytenr,
6379 new_extents[0].disk_num_bytes,
6381 root->root_key.objectid,
6386 ret = btrfs_free_extent(trans, root,
6387 extent_key->objectid,
6390 btrfs_header_owner(leaf),
6391 btrfs_header_generation(leaf),
6395 btrfs_release_path(root, path);
6396 key.offset += num_bytes;
6404 * drop old extent pointer at first, then insert the
6405 * new pointers one bye one
6407 btrfs_release_path(root, path);
6408 ret = btrfs_drop_extents(trans, root, inode, key.offset,
6409 key.offset + num_bytes,
6410 key.offset, &alloc_hint);
6413 for (i = 0; i < nr_extents; i++) {
6414 if (ext_offset >= new_extents[i].num_bytes) {
6415 ext_offset -= new_extents[i].num_bytes;
6418 extent_len = min(new_extents[i].num_bytes -
6419 ext_offset, num_bytes);
6421 ret = btrfs_insert_empty_item(trans, root,
6426 leaf = path->nodes[0];
6427 fi = btrfs_item_ptr(leaf, path->slots[0],
6428 struct btrfs_file_extent_item);
6429 btrfs_set_file_extent_generation(leaf, fi,
6431 btrfs_set_file_extent_type(leaf, fi,
6432 BTRFS_FILE_EXTENT_REG);
6433 btrfs_set_file_extent_disk_bytenr(leaf, fi,
6434 new_extents[i].disk_bytenr);
6435 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
6436 new_extents[i].disk_num_bytes);
6437 btrfs_set_file_extent_ram_bytes(leaf, fi,
6438 new_extents[i].ram_bytes);
6440 btrfs_set_file_extent_compression(leaf, fi,
6441 new_extents[i].compression);
6442 btrfs_set_file_extent_encryption(leaf, fi,
6443 new_extents[i].encryption);
6444 btrfs_set_file_extent_other_encoding(leaf, fi,
6445 new_extents[i].other_encoding);
6447 btrfs_set_file_extent_num_bytes(leaf, fi,
6449 ext_offset += new_extents[i].offset;
6450 btrfs_set_file_extent_offset(leaf, fi,
6452 btrfs_mark_buffer_dirty(leaf);
6454 btrfs_drop_extent_cache(inode, key.offset,
6455 key.offset + extent_len - 1, 0);
6457 ret = btrfs_inc_extent_ref(trans, root,
6458 new_extents[i].disk_bytenr,
6459 new_extents[i].disk_num_bytes,
6461 root->root_key.objectid,
6462 trans->transid, key.objectid);
6464 btrfs_release_path(root, path);
6466 inode_add_bytes(inode, extent_len);
6469 num_bytes -= extent_len;
6470 key.offset += extent_len;
6475 BUG_ON(i >= nr_extents);
6479 if (extent_locked) {
6480 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
6481 lock_end, GFP_NOFS);
6485 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS &&
6486 key.offset >= search_end)
6493 btrfs_release_path(root, path);
6495 mutex_unlock(&inode->i_mutex);
6496 if (extent_locked) {
6497 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
6498 lock_end, GFP_NOFS);
6505 int btrfs_reloc_tree_cache_ref(struct btrfs_trans_handle *trans,
6506 struct btrfs_root *root,
6507 struct extent_buffer *buf, u64 orig_start)
6512 BUG_ON(btrfs_header_generation(buf) != trans->transid);
6513 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
6515 level = btrfs_header_level(buf);
6517 struct btrfs_leaf_ref *ref;
6518 struct btrfs_leaf_ref *orig_ref;
6520 orig_ref = btrfs_lookup_leaf_ref(root, orig_start);
6524 ref = btrfs_alloc_leaf_ref(root, orig_ref->nritems);
6526 btrfs_free_leaf_ref(root, orig_ref);
6530 ref->nritems = orig_ref->nritems;
6531 memcpy(ref->extents, orig_ref->extents,
6532 sizeof(ref->extents[0]) * ref->nritems);
6534 btrfs_free_leaf_ref(root, orig_ref);
6536 ref->root_gen = trans->transid;
6537 ref->bytenr = buf->start;
6538 ref->owner = btrfs_header_owner(buf);
6539 ref->generation = btrfs_header_generation(buf);
6541 ret = btrfs_add_leaf_ref(root, ref, 0);
6543 btrfs_free_leaf_ref(root, ref);
6548 static noinline int invalidate_extent_cache(struct btrfs_root *root,
6549 struct extent_buffer *leaf,
6550 struct btrfs_block_group_cache *group,
6551 struct btrfs_root *target_root)
6553 struct btrfs_key key;
6554 struct inode *inode = NULL;
6555 struct btrfs_file_extent_item *fi;
6557 u64 skip_objectid = 0;
6561 nritems = btrfs_header_nritems(leaf);
6562 for (i = 0; i < nritems; i++) {
6563 btrfs_item_key_to_cpu(leaf, &key, i);
6564 if (key.objectid == skip_objectid ||
6565 key.type != BTRFS_EXTENT_DATA_KEY)
6567 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
6568 if (btrfs_file_extent_type(leaf, fi) ==
6569 BTRFS_FILE_EXTENT_INLINE)
6571 if (btrfs_file_extent_disk_bytenr(leaf, fi) == 0)
6573 if (!inode || inode->i_ino != key.objectid) {
6575 inode = btrfs_ilookup(target_root->fs_info->sb,
6576 key.objectid, target_root, 1);
6579 skip_objectid = key.objectid;
6582 num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
6584 lock_extent(&BTRFS_I(inode)->io_tree, key.offset,
6585 key.offset + num_bytes - 1, GFP_NOFS);
6586 btrfs_drop_extent_cache(inode, key.offset,
6587 key.offset + num_bytes - 1, 1);
6588 unlock_extent(&BTRFS_I(inode)->io_tree, key.offset,
6589 key.offset + num_bytes - 1, GFP_NOFS);
6596 static noinline int replace_extents_in_leaf(struct btrfs_trans_handle *trans,
6597 struct btrfs_root *root,
6598 struct extent_buffer *leaf,
6599 struct btrfs_block_group_cache *group,
6600 struct inode *reloc_inode)
6602 struct btrfs_key key;
6603 struct btrfs_key extent_key;
6604 struct btrfs_file_extent_item *fi;
6605 struct btrfs_leaf_ref *ref;
6606 struct disk_extent *new_extent;
6615 new_extent = kmalloc(sizeof(*new_extent), GFP_NOFS);
6616 BUG_ON(!new_extent);
6618 ref = btrfs_lookup_leaf_ref(root, leaf->start);
6622 nritems = btrfs_header_nritems(leaf);
6623 for (i = 0; i < nritems; i++) {
6624 btrfs_item_key_to_cpu(leaf, &key, i);
6625 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
6627 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
6628 if (btrfs_file_extent_type(leaf, fi) ==
6629 BTRFS_FILE_EXTENT_INLINE)
6631 bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
6632 num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
6637 if (bytenr >= group->key.objectid + group->key.offset ||
6638 bytenr + num_bytes <= group->key.objectid)
6641 extent_key.objectid = bytenr;
6642 extent_key.offset = num_bytes;
6643 extent_key.type = BTRFS_EXTENT_ITEM_KEY;
6645 ret = get_new_locations(reloc_inode, &extent_key,
6646 group->key.objectid, 1,
6647 &new_extent, &nr_extent);
6652 BUG_ON(ref->extents[ext_index].bytenr != bytenr);
6653 BUG_ON(ref->extents[ext_index].num_bytes != num_bytes);
6654 ref->extents[ext_index].bytenr = new_extent->disk_bytenr;
6655 ref->extents[ext_index].num_bytes = new_extent->disk_num_bytes;
6657 btrfs_set_file_extent_disk_bytenr(leaf, fi,
6658 new_extent->disk_bytenr);
6659 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
6660 new_extent->disk_num_bytes);
6661 btrfs_mark_buffer_dirty(leaf);
6663 ret = btrfs_inc_extent_ref(trans, root,
6664 new_extent->disk_bytenr,
6665 new_extent->disk_num_bytes,
6667 root->root_key.objectid,
6668 trans->transid, key.objectid);
6671 ret = btrfs_free_extent(trans, root,
6672 bytenr, num_bytes, leaf->start,
6673 btrfs_header_owner(leaf),
6674 btrfs_header_generation(leaf),
6680 BUG_ON(ext_index + 1 != ref->nritems);
6681 btrfs_free_leaf_ref(root, ref);
6685 int btrfs_free_reloc_root(struct btrfs_trans_handle *trans,
6686 struct btrfs_root *root)
6688 struct btrfs_root *reloc_root;
6691 if (root->reloc_root) {
6692 reloc_root = root->reloc_root;
6693 root->reloc_root = NULL;
6694 list_add(&reloc_root->dead_list,
6695 &root->fs_info->dead_reloc_roots);
6697 btrfs_set_root_bytenr(&reloc_root->root_item,
6698 reloc_root->node->start);
6699 btrfs_set_root_level(&root->root_item,
6700 btrfs_header_level(reloc_root->node));
6701 memset(&reloc_root->root_item.drop_progress, 0,
6702 sizeof(struct btrfs_disk_key));
6703 reloc_root->root_item.drop_level = 0;
6705 ret = btrfs_update_root(trans, root->fs_info->tree_root,
6706 &reloc_root->root_key,
6707 &reloc_root->root_item);
6713 int btrfs_drop_dead_reloc_roots(struct btrfs_root *root)
6715 struct btrfs_trans_handle *trans;
6716 struct btrfs_root *reloc_root;
6717 struct btrfs_root *prev_root = NULL;
6718 struct list_head dead_roots;
6722 INIT_LIST_HEAD(&dead_roots);
6723 list_splice_init(&root->fs_info->dead_reloc_roots, &dead_roots);
6725 while (!list_empty(&dead_roots)) {
6726 reloc_root = list_entry(dead_roots.prev,
6727 struct btrfs_root, dead_list);
6728 list_del_init(&reloc_root->dead_list);
6730 BUG_ON(reloc_root->commit_root != NULL);
6732 trans = btrfs_join_transaction(root, 1);
6735 mutex_lock(&root->fs_info->drop_mutex);
6736 ret = btrfs_drop_snapshot(trans, reloc_root);
6739 mutex_unlock(&root->fs_info->drop_mutex);
6741 nr = trans->blocks_used;
6742 ret = btrfs_end_transaction(trans, root);
6744 btrfs_btree_balance_dirty(root, nr);
6747 free_extent_buffer(reloc_root->node);
6749 ret = btrfs_del_root(trans, root->fs_info->tree_root,
6750 &reloc_root->root_key);
6752 mutex_unlock(&root->fs_info->drop_mutex);
6754 nr = trans->blocks_used;
6755 ret = btrfs_end_transaction(trans, root);
6757 btrfs_btree_balance_dirty(root, nr);
6760 prev_root = reloc_root;
6763 btrfs_remove_leaf_refs(prev_root, (u64)-1, 0);
6769 int btrfs_add_dead_reloc_root(struct btrfs_root *root)
6771 list_add(&root->dead_list, &root->fs_info->dead_reloc_roots);
6775 int btrfs_cleanup_reloc_trees(struct btrfs_root *root)
6777 struct btrfs_root *reloc_root;
6778 struct btrfs_trans_handle *trans;
6779 struct btrfs_key location;
6783 mutex_lock(&root->fs_info->tree_reloc_mutex);
6784 ret = btrfs_find_dead_roots(root, BTRFS_TREE_RELOC_OBJECTID, NULL);
6786 found = !list_empty(&root->fs_info->dead_reloc_roots);
6787 mutex_unlock(&root->fs_info->tree_reloc_mutex);
6790 trans = btrfs_start_transaction(root, 1);
6792 ret = btrfs_commit_transaction(trans, root);
6796 location.objectid = BTRFS_DATA_RELOC_TREE_OBJECTID;
6797 location.offset = (u64)-1;
6798 location.type = BTRFS_ROOT_ITEM_KEY;
6800 reloc_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
6801 BUG_ON(!reloc_root);
6802 btrfs_orphan_cleanup(reloc_root);
6806 static noinline int init_reloc_tree(struct btrfs_trans_handle *trans,
6807 struct btrfs_root *root)
6809 struct btrfs_root *reloc_root;
6810 struct extent_buffer *eb;
6811 struct btrfs_root_item *root_item;
6812 struct btrfs_key root_key;
6815 BUG_ON(!root->ref_cows);
6816 if (root->reloc_root)
6819 root_item = kmalloc(sizeof(*root_item), GFP_NOFS);
6822 ret = btrfs_copy_root(trans, root, root->commit_root,
6823 &eb, BTRFS_TREE_RELOC_OBJECTID);
6826 root_key.objectid = BTRFS_TREE_RELOC_OBJECTID;
6827 root_key.offset = root->root_key.objectid;
6828 root_key.type = BTRFS_ROOT_ITEM_KEY;
6830 memcpy(root_item, &root->root_item, sizeof(root_item));
6831 btrfs_set_root_refs(root_item, 0);
6832 btrfs_set_root_bytenr(root_item, eb->start);
6833 btrfs_set_root_level(root_item, btrfs_header_level(eb));
6834 btrfs_set_root_generation(root_item, trans->transid);
6836 btrfs_tree_unlock(eb);
6837 free_extent_buffer(eb);
6839 ret = btrfs_insert_root(trans, root->fs_info->tree_root,
6840 &root_key, root_item);
6844 reloc_root = btrfs_read_fs_root_no_radix(root->fs_info->tree_root,
6846 BUG_ON(!reloc_root);
6847 reloc_root->last_trans = trans->transid;
6848 reloc_root->commit_root = NULL;
6849 reloc_root->ref_tree = &root->fs_info->reloc_ref_tree;
6851 root->reloc_root = reloc_root;
6856 * Core function of space balance.
6858 * The idea is using reloc trees to relocate tree blocks in reference
6859 * counted roots. There is one reloc tree for each subvol, and all
6860 * reloc trees share same root key objectid. Reloc trees are snapshots
6861 * of the latest committed roots of subvols (root->commit_root).
6863 * To relocate a tree block referenced by a subvol, there are two steps.
6864 * COW the block through subvol's reloc tree, then update block pointer
6865 * in the subvol to point to the new block. Since all reloc trees share
6866 * same root key objectid, doing special handing for tree blocks owned
6867 * by them is easy. Once a tree block has been COWed in one reloc tree,
6868 * we can use the resulting new block directly when the same block is
6869 * required to COW again through other reloc trees. By this way, relocated
6870 * tree blocks are shared between reloc trees, so they are also shared
6873 static noinline int relocate_one_path(struct btrfs_trans_handle *trans,
6874 struct btrfs_root *root,
6875 struct btrfs_path *path,
6876 struct btrfs_key *first_key,
6877 struct btrfs_ref_path *ref_path,
6878 struct btrfs_block_group_cache *group,
6879 struct inode *reloc_inode)
6881 struct btrfs_root *reloc_root;
6882 struct extent_buffer *eb = NULL;
6883 struct btrfs_key *keys;
6887 int lowest_level = 0;
6890 if (ref_path->owner_objectid < BTRFS_FIRST_FREE_OBJECTID)
6891 lowest_level = ref_path->owner_objectid;
6893 if (!root->ref_cows) {
6894 path->lowest_level = lowest_level;
6895 ret = btrfs_search_slot(trans, root, first_key, path, 0, 1);
6897 path->lowest_level = 0;
6898 btrfs_release_path(root, path);
6902 mutex_lock(&root->fs_info->tree_reloc_mutex);
6903 ret = init_reloc_tree(trans, root);
6905 reloc_root = root->reloc_root;
6907 shared_level = ref_path->shared_level;
6908 ref_path->shared_level = BTRFS_MAX_LEVEL - 1;
6910 keys = ref_path->node_keys;
6911 nodes = ref_path->new_nodes;
6912 memset(&keys[shared_level + 1], 0,
6913 sizeof(*keys) * (BTRFS_MAX_LEVEL - shared_level - 1));
6914 memset(&nodes[shared_level + 1], 0,
6915 sizeof(*nodes) * (BTRFS_MAX_LEVEL - shared_level - 1));
6917 if (nodes[lowest_level] == 0) {
6918 path->lowest_level = lowest_level;
6919 ret = btrfs_search_slot(trans, reloc_root, first_key, path,
6922 for (level = lowest_level; level < BTRFS_MAX_LEVEL; level++) {
6923 eb = path->nodes[level];
6924 if (!eb || eb == reloc_root->node)
6926 nodes[level] = eb->start;
6928 btrfs_item_key_to_cpu(eb, &keys[level], 0);
6930 btrfs_node_key_to_cpu(eb, &keys[level], 0);
6933 ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
6934 eb = path->nodes[0];
6935 ret = replace_extents_in_leaf(trans, reloc_root, eb,
6936 group, reloc_inode);
6939 btrfs_release_path(reloc_root, path);
6941 ret = btrfs_merge_path(trans, reloc_root, keys, nodes,
6947 * replace tree blocks in the fs tree with tree blocks in
6950 ret = btrfs_merge_path(trans, root, keys, nodes, lowest_level);
6953 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
6954 ret = btrfs_search_slot(trans, reloc_root, first_key, path,
6957 extent_buffer_get(path->nodes[0]);
6958 eb = path->nodes[0];
6959 btrfs_release_path(reloc_root, path);
6960 ret = invalidate_extent_cache(reloc_root, eb, group, root);
6962 free_extent_buffer(eb);
6965 mutex_unlock(&root->fs_info->tree_reloc_mutex);
6966 path->lowest_level = 0;
6970 static noinline int relocate_tree_block(struct btrfs_trans_handle *trans,
6971 struct btrfs_root *root,
6972 struct btrfs_path *path,
6973 struct btrfs_key *first_key,
6974 struct btrfs_ref_path *ref_path)
6978 ret = relocate_one_path(trans, root, path, first_key,
6979 ref_path, NULL, NULL);
6985 static noinline int del_extent_zero(struct btrfs_trans_handle *trans,
6986 struct btrfs_root *extent_root,
6987 struct btrfs_path *path,
6988 struct btrfs_key *extent_key)
6992 ret = btrfs_search_slot(trans, extent_root, extent_key, path, -1, 1);
6995 ret = btrfs_del_item(trans, extent_root, path);
6997 btrfs_release_path(extent_root, path);
7001 static noinline struct btrfs_root *read_ref_root(struct btrfs_fs_info *fs_info,
7002 struct btrfs_ref_path *ref_path)
7004 struct btrfs_key root_key;
7006 root_key.objectid = ref_path->root_objectid;
7007 root_key.type = BTRFS_ROOT_ITEM_KEY;
7008 if (is_cowonly_root(ref_path->root_objectid))
7009 root_key.offset = 0;
7011 root_key.offset = (u64)-1;
7013 return btrfs_read_fs_root_no_name(fs_info, &root_key);
7016 static noinline int relocate_one_extent(struct btrfs_root *extent_root,
7017 struct btrfs_path *path,
7018 struct btrfs_key *extent_key,
7019 struct btrfs_block_group_cache *group,
7020 struct inode *reloc_inode, int pass)
7022 struct btrfs_trans_handle *trans;
7023 struct btrfs_root *found_root;
7024 struct btrfs_ref_path *ref_path = NULL;
7025 struct disk_extent *new_extents = NULL;
7030 struct btrfs_key first_key;
7034 trans = btrfs_start_transaction(extent_root, 1);
7037 if (extent_key->objectid == 0) {
7038 ret = del_extent_zero(trans, extent_root, path, extent_key);
7042 ref_path = kmalloc(sizeof(*ref_path), GFP_NOFS);
7048 for (loops = 0; ; loops++) {
7050 ret = btrfs_first_ref_path(trans, extent_root, ref_path,
7051 extent_key->objectid);
7053 ret = btrfs_next_ref_path(trans, extent_root, ref_path);
7060 if (ref_path->root_objectid == BTRFS_TREE_LOG_OBJECTID ||
7061 ref_path->root_objectid == BTRFS_TREE_RELOC_OBJECTID)
7064 found_root = read_ref_root(extent_root->fs_info, ref_path);
7065 BUG_ON(!found_root);
7067 * for reference counted tree, only process reference paths
7068 * rooted at the latest committed root.
7070 if (found_root->ref_cows &&
7071 ref_path->root_generation != found_root->root_key.offset)
7074 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7077 * copy data extents to new locations
7079 u64 group_start = group->key.objectid;
7080 ret = relocate_data_extent(reloc_inode,
7089 level = ref_path->owner_objectid;
7092 if (prev_block != ref_path->nodes[level]) {
7093 struct extent_buffer *eb;
7094 u64 block_start = ref_path->nodes[level];
7095 u64 block_size = btrfs_level_size(found_root, level);
7097 eb = read_tree_block(found_root, block_start,
7099 btrfs_tree_lock(eb);
7100 BUG_ON(level != btrfs_header_level(eb));
7103 btrfs_item_key_to_cpu(eb, &first_key, 0);
7105 btrfs_node_key_to_cpu(eb, &first_key, 0);
7107 btrfs_tree_unlock(eb);
7108 free_extent_buffer(eb);
7109 prev_block = block_start;
7112 mutex_lock(&extent_root->fs_info->trans_mutex);
7113 btrfs_record_root_in_trans(found_root);
7114 mutex_unlock(&extent_root->fs_info->trans_mutex);
7115 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
7117 * try to update data extent references while
7118 * keeping metadata shared between snapshots.
7121 ret = relocate_one_path(trans, found_root,
7122 path, &first_key, ref_path,
7123 group, reloc_inode);
7129 * use fallback method to process the remaining
7133 u64 group_start = group->key.objectid;
7134 new_extents = kmalloc(sizeof(*new_extents),
7137 ret = get_new_locations(reloc_inode,
7145 ret = replace_one_extent(trans, found_root,
7147 &first_key, ref_path,
7148 new_extents, nr_extents);
7150 ret = relocate_tree_block(trans, found_root, path,
7151 &first_key, ref_path);
7158 btrfs_end_transaction(trans, extent_root);
7165 static u64 update_block_group_flags(struct btrfs_root *root, u64 flags)
7168 u64 stripped = BTRFS_BLOCK_GROUP_RAID0 |
7169 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
7171 num_devices = root->fs_info->fs_devices->rw_devices;
7172 if (num_devices == 1) {
7173 stripped |= BTRFS_BLOCK_GROUP_DUP;
7174 stripped = flags & ~stripped;
7176 /* turn raid0 into single device chunks */
7177 if (flags & BTRFS_BLOCK_GROUP_RAID0)
7180 /* turn mirroring into duplication */
7181 if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
7182 BTRFS_BLOCK_GROUP_RAID10))
7183 return stripped | BTRFS_BLOCK_GROUP_DUP;
7186 /* they already had raid on here, just return */
7187 if (flags & stripped)
7190 stripped |= BTRFS_BLOCK_GROUP_DUP;
7191 stripped = flags & ~stripped;
7193 /* switch duplicated blocks with raid1 */
7194 if (flags & BTRFS_BLOCK_GROUP_DUP)
7195 return stripped | BTRFS_BLOCK_GROUP_RAID1;
7197 /* turn single device chunks into raid0 */
7198 return stripped | BTRFS_BLOCK_GROUP_RAID0;
7203 static int __alloc_chunk_for_shrink(struct btrfs_root *root,
7204 struct btrfs_block_group_cache *shrink_block_group,
7207 struct btrfs_trans_handle *trans;
7208 u64 new_alloc_flags;
7211 spin_lock(&shrink_block_group->lock);
7212 if (btrfs_block_group_used(&shrink_block_group->item) +
7213 shrink_block_group->reserved > 0) {
7214 spin_unlock(&shrink_block_group->lock);
7216 trans = btrfs_start_transaction(root, 1);
7217 spin_lock(&shrink_block_group->lock);
7219 new_alloc_flags = update_block_group_flags(root,
7220 shrink_block_group->flags);
7221 if (new_alloc_flags != shrink_block_group->flags) {
7223 btrfs_block_group_used(&shrink_block_group->item);
7225 calc = shrink_block_group->key.offset;
7227 spin_unlock(&shrink_block_group->lock);
7229 do_chunk_alloc(trans, root->fs_info->extent_root,
7230 calc + 2 * 1024 * 1024, new_alloc_flags, force);
7232 btrfs_end_transaction(trans, root);
7234 spin_unlock(&shrink_block_group->lock);
7239 int btrfs_prepare_block_group_relocation(struct btrfs_root *root,
7240 struct btrfs_block_group_cache *group)
7243 __alloc_chunk_for_shrink(root, group, 1);
7244 set_block_group_readonly(group);
7249 * checks to see if its even possible to relocate this block group.
7251 * @return - -1 if it's not a good idea to relocate this block group, 0 if its
7252 * ok to go ahead and try.
7254 int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
7256 struct btrfs_block_group_cache *block_group;
7257 struct btrfs_space_info *space_info;
7258 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
7259 struct btrfs_device *device;
7263 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
7265 /* odd, couldn't find the block group, leave it alone */
7269 /* no bytes used, we're good */
7270 if (!btrfs_block_group_used(&block_group->item))
7273 space_info = block_group->space_info;
7274 spin_lock(&space_info->lock);
7276 full = space_info->full;
7279 * if this is the last block group we have in this space, we can't
7280 * relocate it unless we're able to allocate a new chunk below.
7282 * Otherwise, we need to make sure we have room in the space to handle
7283 * all of the extents from this block group. If we can, we're good
7285 if ((space_info->total_bytes != block_group->key.offset) &&
7286 (space_info->bytes_used + space_info->bytes_reserved +
7287 space_info->bytes_pinned + space_info->bytes_readonly +
7288 btrfs_block_group_used(&block_group->item) <
7289 space_info->total_bytes)) {
7290 spin_unlock(&space_info->lock);
7293 spin_unlock(&space_info->lock);
7296 * ok we don't have enough space, but maybe we have free space on our
7297 * devices to allocate new chunks for relocation, so loop through our
7298 * alloc devices and guess if we have enough space. However, if we
7299 * were marked as full, then we know there aren't enough chunks, and we
7306 mutex_lock(&root->fs_info->chunk_mutex);
7307 list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
7308 u64 min_free = btrfs_block_group_used(&block_group->item);
7309 u64 dev_offset, max_avail;
7312 * check to make sure we can actually find a chunk with enough
7313 * space to fit our block group in.
7315 if (device->total_bytes > device->bytes_used + min_free) {
7316 ret = find_free_dev_extent(NULL, device, min_free,
7317 &dev_offset, &max_avail);
7323 mutex_unlock(&root->fs_info->chunk_mutex);
7325 btrfs_put_block_group(block_group);
7329 static int find_first_block_group(struct btrfs_root *root,
7330 struct btrfs_path *path, struct btrfs_key *key)
7333 struct btrfs_key found_key;
7334 struct extent_buffer *leaf;
7337 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
7342 slot = path->slots[0];
7343 leaf = path->nodes[0];
7344 if (slot >= btrfs_header_nritems(leaf)) {
7345 ret = btrfs_next_leaf(root, path);
7352 btrfs_item_key_to_cpu(leaf, &found_key, slot);
7354 if (found_key.objectid >= key->objectid &&
7355 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
7366 int btrfs_free_block_groups(struct btrfs_fs_info *info)
7368 struct btrfs_block_group_cache *block_group;
7369 struct btrfs_space_info *space_info;
7370 struct btrfs_caching_control *caching_ctl;
7373 down_write(&info->extent_commit_sem);
7374 while (!list_empty(&info->caching_block_groups)) {
7375 caching_ctl = list_entry(info->caching_block_groups.next,
7376 struct btrfs_caching_control, list);
7377 list_del(&caching_ctl->list);
7378 put_caching_control(caching_ctl);
7380 up_write(&info->extent_commit_sem);
7382 spin_lock(&info->block_group_cache_lock);
7383 while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
7384 block_group = rb_entry(n, struct btrfs_block_group_cache,
7386 rb_erase(&block_group->cache_node,
7387 &info->block_group_cache_tree);
7388 spin_unlock(&info->block_group_cache_lock);
7390 down_write(&block_group->space_info->groups_sem);
7391 list_del(&block_group->list);
7392 up_write(&block_group->space_info->groups_sem);
7394 if (block_group->cached == BTRFS_CACHE_STARTED)
7395 wait_block_group_cache_done(block_group);
7397 btrfs_remove_free_space_cache(block_group);
7399 WARN_ON(atomic_read(&block_group->count) != 1);
7402 spin_lock(&info->block_group_cache_lock);
7404 spin_unlock(&info->block_group_cache_lock);
7406 /* now that all the block groups are freed, go through and
7407 * free all the space_info structs. This is only called during
7408 * the final stages of unmount, and so we know nobody is
7409 * using them. We call synchronize_rcu() once before we start,
7410 * just to be on the safe side.
7414 while(!list_empty(&info->space_info)) {
7415 space_info = list_entry(info->space_info.next,
7416 struct btrfs_space_info,
7419 list_del(&space_info->list);
7425 int btrfs_read_block_groups(struct btrfs_root *root)
7427 struct btrfs_path *path;
7429 struct btrfs_block_group_cache *cache;
7430 struct btrfs_fs_info *info = root->fs_info;
7431 struct btrfs_space_info *space_info;
7432 struct btrfs_key key;
7433 struct btrfs_key found_key;
7434 struct extent_buffer *leaf;
7436 root = info->extent_root;
7439 btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
7440 path = btrfs_alloc_path();
7445 ret = find_first_block_group(root, path, &key);
7453 leaf = path->nodes[0];
7454 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
7455 cache = kzalloc(sizeof(*cache), GFP_NOFS);
7461 atomic_set(&cache->count, 1);
7462 spin_lock_init(&cache->lock);
7463 spin_lock_init(&cache->tree_lock);
7464 cache->fs_info = info;
7465 INIT_LIST_HEAD(&cache->list);
7466 INIT_LIST_HEAD(&cache->cluster_list);
7469 * we only want to have 32k of ram per block group for keeping
7470 * track of free space, and if we pass 1/2 of that we want to
7471 * start converting things over to using bitmaps
7473 cache->extents_thresh = ((1024 * 32) / 2) /
7474 sizeof(struct btrfs_free_space);
7476 read_extent_buffer(leaf, &cache->item,
7477 btrfs_item_ptr_offset(leaf, path->slots[0]),
7478 sizeof(cache->item));
7479 memcpy(&cache->key, &found_key, sizeof(found_key));
7481 key.objectid = found_key.objectid + found_key.offset;
7482 btrfs_release_path(root, path);
7483 cache->flags = btrfs_block_group_flags(&cache->item);
7484 cache->sectorsize = root->sectorsize;
7487 * check for two cases, either we are full, and therefore
7488 * don't need to bother with the caching work since we won't
7489 * find any space, or we are empty, and we can just add all
7490 * the space in and be done with it. This saves us _alot_ of
7491 * time, particularly in the full case.
7493 if (found_key.offset == btrfs_block_group_used(&cache->item)) {
7494 exclude_super_stripes(root, cache);
7495 cache->last_byte_to_unpin = (u64)-1;
7496 cache->cached = BTRFS_CACHE_FINISHED;
7497 free_excluded_extents(root, cache);
7498 } else if (btrfs_block_group_used(&cache->item) == 0) {
7499 exclude_super_stripes(root, cache);
7500 cache->last_byte_to_unpin = (u64)-1;
7501 cache->cached = BTRFS_CACHE_FINISHED;
7502 add_new_free_space(cache, root->fs_info,
7504 found_key.objectid +
7506 free_excluded_extents(root, cache);
7509 ret = update_space_info(info, cache->flags, found_key.offset,
7510 btrfs_block_group_used(&cache->item),
7513 cache->space_info = space_info;
7514 spin_lock(&cache->space_info->lock);
7515 cache->space_info->bytes_super += cache->bytes_super;
7516 spin_unlock(&cache->space_info->lock);
7518 down_write(&space_info->groups_sem);
7519 list_add_tail(&cache->list, &space_info->block_groups);
7520 up_write(&space_info->groups_sem);
7522 ret = btrfs_add_block_group_cache(root->fs_info, cache);
7525 set_avail_alloc_bits(root->fs_info, cache->flags);
7526 if (btrfs_chunk_readonly(root, cache->key.objectid))
7527 set_block_group_readonly(cache);
7531 btrfs_free_path(path);
7535 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
7536 struct btrfs_root *root, u64 bytes_used,
7537 u64 type, u64 chunk_objectid, u64 chunk_offset,
7541 struct btrfs_root *extent_root;
7542 struct btrfs_block_group_cache *cache;
7544 extent_root = root->fs_info->extent_root;
7546 root->fs_info->last_trans_log_full_commit = trans->transid;
7548 cache = kzalloc(sizeof(*cache), GFP_NOFS);
7552 cache->key.objectid = chunk_offset;
7553 cache->key.offset = size;
7554 cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
7555 cache->sectorsize = root->sectorsize;
7558 * we only want to have 32k of ram per block group for keeping track
7559 * of free space, and if we pass 1/2 of that we want to start
7560 * converting things over to using bitmaps
7562 cache->extents_thresh = ((1024 * 32) / 2) /
7563 sizeof(struct btrfs_free_space);
7564 atomic_set(&cache->count, 1);
7565 spin_lock_init(&cache->lock);
7566 spin_lock_init(&cache->tree_lock);
7567 INIT_LIST_HEAD(&cache->list);
7568 INIT_LIST_HEAD(&cache->cluster_list);
7570 btrfs_set_block_group_used(&cache->item, bytes_used);
7571 btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
7572 cache->flags = type;
7573 btrfs_set_block_group_flags(&cache->item, type);
7575 cache->last_byte_to_unpin = (u64)-1;
7576 cache->cached = BTRFS_CACHE_FINISHED;
7577 exclude_super_stripes(root, cache);
7579 add_new_free_space(cache, root->fs_info, chunk_offset,
7580 chunk_offset + size);
7582 free_excluded_extents(root, cache);
7584 ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
7585 &cache->space_info);
7588 spin_lock(&cache->space_info->lock);
7589 cache->space_info->bytes_super += cache->bytes_super;
7590 spin_unlock(&cache->space_info->lock);
7592 down_write(&cache->space_info->groups_sem);
7593 list_add_tail(&cache->list, &cache->space_info->block_groups);
7594 up_write(&cache->space_info->groups_sem);
7596 ret = btrfs_add_block_group_cache(root->fs_info, cache);
7599 ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
7600 sizeof(cache->item));
7603 set_avail_alloc_bits(extent_root->fs_info, type);
7608 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
7609 struct btrfs_root *root, u64 group_start)
7611 struct btrfs_path *path;
7612 struct btrfs_block_group_cache *block_group;
7613 struct btrfs_free_cluster *cluster;
7614 struct btrfs_key key;
7617 root = root->fs_info->extent_root;
7619 block_group = btrfs_lookup_block_group(root->fs_info, group_start);
7620 BUG_ON(!block_group);
7621 BUG_ON(!block_group->ro);
7623 memcpy(&key, &block_group->key, sizeof(key));
7625 /* make sure this block group isn't part of an allocation cluster */
7626 cluster = &root->fs_info->data_alloc_cluster;
7627 spin_lock(&cluster->refill_lock);
7628 btrfs_return_cluster_to_free_space(block_group, cluster);
7629 spin_unlock(&cluster->refill_lock);
7632 * make sure this block group isn't part of a metadata
7633 * allocation cluster
7635 cluster = &root->fs_info->meta_alloc_cluster;
7636 spin_lock(&cluster->refill_lock);
7637 btrfs_return_cluster_to_free_space(block_group, cluster);
7638 spin_unlock(&cluster->refill_lock);
7640 path = btrfs_alloc_path();
7643 spin_lock(&root->fs_info->block_group_cache_lock);
7644 rb_erase(&block_group->cache_node,
7645 &root->fs_info->block_group_cache_tree);
7646 spin_unlock(&root->fs_info->block_group_cache_lock);
7648 down_write(&block_group->space_info->groups_sem);
7650 * we must use list_del_init so people can check to see if they
7651 * are still on the list after taking the semaphore
7653 list_del_init(&block_group->list);
7654 up_write(&block_group->space_info->groups_sem);
7656 if (block_group->cached == BTRFS_CACHE_STARTED)
7657 wait_block_group_cache_done(block_group);
7659 btrfs_remove_free_space_cache(block_group);
7661 spin_lock(&block_group->space_info->lock);
7662 block_group->space_info->total_bytes -= block_group->key.offset;
7663 block_group->space_info->bytes_readonly -= block_group->key.offset;
7664 spin_unlock(&block_group->space_info->lock);
7666 btrfs_clear_space_info_full(root->fs_info);
7668 btrfs_put_block_group(block_group);
7669 btrfs_put_block_group(block_group);
7671 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
7677 ret = btrfs_del_item(trans, root, path);
7679 btrfs_free_path(path);