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);
73 block_group_cache_done(struct btrfs_block_group_cache *cache)
76 return cache->cached == BTRFS_CACHE_FINISHED;
79 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
81 return (cache->flags & bits) == bits;
85 * this adds the block group to the fs_info rb tree for the block group
88 static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
89 struct btrfs_block_group_cache *block_group)
92 struct rb_node *parent = NULL;
93 struct btrfs_block_group_cache *cache;
95 spin_lock(&info->block_group_cache_lock);
96 p = &info->block_group_cache_tree.rb_node;
100 cache = rb_entry(parent, struct btrfs_block_group_cache,
102 if (block_group->key.objectid < cache->key.objectid) {
104 } else if (block_group->key.objectid > cache->key.objectid) {
107 spin_unlock(&info->block_group_cache_lock);
112 rb_link_node(&block_group->cache_node, parent, p);
113 rb_insert_color(&block_group->cache_node,
114 &info->block_group_cache_tree);
115 spin_unlock(&info->block_group_cache_lock);
121 * This will return the block group at or after bytenr if contains is 0, else
122 * it will return the block group that contains the bytenr
124 static struct btrfs_block_group_cache *
125 block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
128 struct btrfs_block_group_cache *cache, *ret = NULL;
132 spin_lock(&info->block_group_cache_lock);
133 n = info->block_group_cache_tree.rb_node;
136 cache = rb_entry(n, struct btrfs_block_group_cache,
138 end = cache->key.objectid + cache->key.offset - 1;
139 start = cache->key.objectid;
141 if (bytenr < start) {
142 if (!contains && (!ret || start < ret->key.objectid))
145 } else if (bytenr > start) {
146 if (contains && bytenr <= end) {
157 atomic_inc(&ret->count);
158 spin_unlock(&info->block_group_cache_lock);
163 static int add_excluded_extent(struct btrfs_root *root,
164 u64 start, u64 num_bytes)
166 u64 end = start + num_bytes - 1;
167 set_extent_bits(&root->fs_info->freed_extents[0],
168 start, end, EXTENT_UPTODATE, GFP_NOFS);
169 set_extent_bits(&root->fs_info->freed_extents[1],
170 start, end, EXTENT_UPTODATE, GFP_NOFS);
174 static void free_excluded_extents(struct btrfs_root *root,
175 struct btrfs_block_group_cache *cache)
179 start = cache->key.objectid;
180 end = start + cache->key.offset - 1;
182 clear_extent_bits(&root->fs_info->freed_extents[0],
183 start, end, EXTENT_UPTODATE, GFP_NOFS);
184 clear_extent_bits(&root->fs_info->freed_extents[1],
185 start, end, EXTENT_UPTODATE, GFP_NOFS);
188 static int exclude_super_stripes(struct btrfs_root *root,
189 struct btrfs_block_group_cache *cache)
196 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
197 bytenr = btrfs_sb_offset(i);
198 ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
199 cache->key.objectid, bytenr,
200 0, &logical, &nr, &stripe_len);
204 cache->bytes_super += stripe_len;
205 ret = add_excluded_extent(root, logical[nr],
215 static struct btrfs_caching_control *
216 get_caching_control(struct btrfs_block_group_cache *cache)
218 struct btrfs_caching_control *ctl;
220 spin_lock(&cache->lock);
221 if (cache->cached != BTRFS_CACHE_STARTED) {
222 spin_unlock(&cache->lock);
226 ctl = cache->caching_ctl;
227 atomic_inc(&ctl->count);
228 spin_unlock(&cache->lock);
232 static void put_caching_control(struct btrfs_caching_control *ctl)
234 if (atomic_dec_and_test(&ctl->count))
239 * this is only called by cache_block_group, since we could have freed extents
240 * we need to check the pinned_extents for any extents that can't be used yet
241 * since their free space will be released as soon as the transaction commits.
243 static u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
244 struct btrfs_fs_info *info, u64 start, u64 end)
246 u64 extent_start, extent_end, size, total_added = 0;
249 while (start < end) {
250 ret = find_first_extent_bit(info->pinned_extents, start,
251 &extent_start, &extent_end,
252 EXTENT_DIRTY | EXTENT_UPTODATE);
256 if (extent_start == start) {
257 start = extent_end + 1;
258 } else if (extent_start > start && extent_start < end) {
259 size = extent_start - start;
261 ret = btrfs_add_free_space(block_group, start,
264 start = extent_end + 1;
273 ret = btrfs_add_free_space(block_group, start, size);
280 static int caching_kthread(void *data)
282 struct btrfs_block_group_cache *block_group = data;
283 struct btrfs_fs_info *fs_info = block_group->fs_info;
284 struct btrfs_caching_control *caching_ctl = block_group->caching_ctl;
285 struct btrfs_root *extent_root = fs_info->extent_root;
286 struct btrfs_path *path;
287 struct extent_buffer *leaf;
288 struct btrfs_key key;
294 path = btrfs_alloc_path();
298 exclude_super_stripes(extent_root, block_group);
299 spin_lock(&block_group->space_info->lock);
300 block_group->space_info->bytes_super += block_group->bytes_super;
301 spin_unlock(&block_group->space_info->lock);
303 last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
306 * We don't want to deadlock with somebody trying to allocate a new
307 * extent for the extent root while also trying to search the extent
308 * root to add free space. So we skip locking and search the commit
309 * root, since its read-only
311 path->skip_locking = 1;
312 path->search_commit_root = 1;
317 key.type = BTRFS_EXTENT_ITEM_KEY;
319 mutex_lock(&caching_ctl->mutex);
320 /* need to make sure the commit_root doesn't disappear */
321 down_read(&fs_info->extent_commit_sem);
323 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
327 leaf = path->nodes[0];
328 nritems = btrfs_header_nritems(leaf);
332 if (fs_info->closing > 1) {
337 if (path->slots[0] < nritems) {
338 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
340 ret = find_next_key(path, 0, &key);
344 caching_ctl->progress = last;
345 btrfs_release_path(extent_root, path);
346 up_read(&fs_info->extent_commit_sem);
347 mutex_unlock(&caching_ctl->mutex);
348 if (btrfs_transaction_in_commit(fs_info))
355 if (key.objectid < block_group->key.objectid) {
360 if (key.objectid >= block_group->key.objectid +
361 block_group->key.offset)
364 if (key.type == BTRFS_EXTENT_ITEM_KEY) {
365 total_found += add_new_free_space(block_group,
368 last = key.objectid + key.offset;
370 if (total_found > (1024 * 1024 * 2)) {
372 wake_up(&caching_ctl->wait);
379 total_found += add_new_free_space(block_group, fs_info, last,
380 block_group->key.objectid +
381 block_group->key.offset);
382 caching_ctl->progress = (u64)-1;
384 spin_lock(&block_group->lock);
385 block_group->caching_ctl = NULL;
386 block_group->cached = BTRFS_CACHE_FINISHED;
387 spin_unlock(&block_group->lock);
390 btrfs_free_path(path);
391 up_read(&fs_info->extent_commit_sem);
393 free_excluded_extents(extent_root, block_group);
395 mutex_unlock(&caching_ctl->mutex);
396 wake_up(&caching_ctl->wait);
398 put_caching_control(caching_ctl);
399 atomic_dec(&block_group->space_info->caching_threads);
403 static int cache_block_group(struct btrfs_block_group_cache *cache)
405 struct btrfs_fs_info *fs_info = cache->fs_info;
406 struct btrfs_caching_control *caching_ctl;
407 struct task_struct *tsk;
411 if (cache->cached != BTRFS_CACHE_NO)
414 caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_KERNEL);
415 BUG_ON(!caching_ctl);
417 INIT_LIST_HEAD(&caching_ctl->list);
418 mutex_init(&caching_ctl->mutex);
419 init_waitqueue_head(&caching_ctl->wait);
420 caching_ctl->block_group = cache;
421 caching_ctl->progress = cache->key.objectid;
422 /* one for caching kthread, one for caching block group list */
423 atomic_set(&caching_ctl->count, 2);
425 spin_lock(&cache->lock);
426 if (cache->cached != BTRFS_CACHE_NO) {
427 spin_unlock(&cache->lock);
431 cache->caching_ctl = caching_ctl;
432 cache->cached = BTRFS_CACHE_STARTED;
433 spin_unlock(&cache->lock);
435 down_write(&fs_info->extent_commit_sem);
436 list_add_tail(&caching_ctl->list, &fs_info->caching_block_groups);
437 up_write(&fs_info->extent_commit_sem);
439 atomic_inc(&cache->space_info->caching_threads);
441 tsk = kthread_run(caching_kthread, cache, "btrfs-cache-%llu\n",
442 cache->key.objectid);
445 printk(KERN_ERR "error running thread %d\n", ret);
453 * return the block group that starts at or after bytenr
455 static struct btrfs_block_group_cache *
456 btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr)
458 struct btrfs_block_group_cache *cache;
460 cache = block_group_cache_tree_search(info, bytenr, 0);
466 * return the block group that contains the given bytenr
468 struct btrfs_block_group_cache *btrfs_lookup_block_group(
469 struct btrfs_fs_info *info,
472 struct btrfs_block_group_cache *cache;
474 cache = block_group_cache_tree_search(info, bytenr, 1);
479 void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
481 if (atomic_dec_and_test(&cache->count))
485 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
488 struct list_head *head = &info->space_info;
489 struct btrfs_space_info *found;
492 list_for_each_entry_rcu(found, head, list) {
493 if (found->flags == flags) {
503 * after adding space to the filesystem, we need to clear the full flags
504 * on all the space infos.
506 void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
508 struct list_head *head = &info->space_info;
509 struct btrfs_space_info *found;
512 list_for_each_entry_rcu(found, head, list)
517 static u64 div_factor(u64 num, int factor)
526 u64 btrfs_find_block_group(struct btrfs_root *root,
527 u64 search_start, u64 search_hint, int owner)
529 struct btrfs_block_group_cache *cache;
531 u64 last = max(search_hint, search_start);
538 cache = btrfs_lookup_first_block_group(root->fs_info, last);
542 spin_lock(&cache->lock);
543 last = cache->key.objectid + cache->key.offset;
544 used = btrfs_block_group_used(&cache->item);
546 if ((full_search || !cache->ro) &&
547 block_group_bits(cache, BTRFS_BLOCK_GROUP_METADATA)) {
548 if (used + cache->pinned + cache->reserved <
549 div_factor(cache->key.offset, factor)) {
550 group_start = cache->key.objectid;
551 spin_unlock(&cache->lock);
552 btrfs_put_block_group(cache);
556 spin_unlock(&cache->lock);
557 btrfs_put_block_group(cache);
565 if (!full_search && factor < 10) {
575 /* simple helper to search for an existing extent at a given offset */
576 int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len)
579 struct btrfs_key key;
580 struct btrfs_path *path;
582 path = btrfs_alloc_path();
584 key.objectid = start;
586 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
587 ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path,
589 btrfs_free_path(path);
594 * Back reference rules. Back refs have three main goals:
596 * 1) differentiate between all holders of references to an extent so that
597 * when a reference is dropped we can make sure it was a valid reference
598 * before freeing the extent.
600 * 2) Provide enough information to quickly find the holders of an extent
601 * if we notice a given block is corrupted or bad.
603 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
604 * maintenance. This is actually the same as #2, but with a slightly
605 * different use case.
607 * There are two kinds of back refs. The implicit back refs is optimized
608 * for pointers in non-shared tree blocks. For a given pointer in a block,
609 * back refs of this kind provide information about the block's owner tree
610 * and the pointer's key. These information allow us to find the block by
611 * b-tree searching. The full back refs is for pointers in tree blocks not
612 * referenced by their owner trees. The location of tree block is recorded
613 * in the back refs. Actually the full back refs is generic, and can be
614 * used in all cases the implicit back refs is used. The major shortcoming
615 * of the full back refs is its overhead. Every time a tree block gets
616 * COWed, we have to update back refs entry for all pointers in it.
618 * For a newly allocated tree block, we use implicit back refs for
619 * pointers in it. This means most tree related operations only involve
620 * implicit back refs. For a tree block created in old transaction, the
621 * only way to drop a reference to it is COW it. So we can detect the
622 * event that tree block loses its owner tree's reference and do the
623 * back refs conversion.
625 * When a tree block is COW'd through a tree, there are four cases:
627 * The reference count of the block is one and the tree is the block's
628 * owner tree. Nothing to do in this case.
630 * The reference count of the block is one and the tree is not the
631 * block's owner tree. In this case, full back refs is used for pointers
632 * in the block. Remove these full back refs, add implicit back refs for
633 * every pointers in the new block.
635 * The reference count of the block is greater than one and the tree is
636 * the block's owner tree. In this case, implicit back refs is used for
637 * pointers in the block. Add full back refs for every pointers in the
638 * block, increase lower level extents' reference counts. The original
639 * implicit back refs are entailed to the new block.
641 * The reference count of the block is greater than one and the tree is
642 * not the block's owner tree. Add implicit back refs for every pointer in
643 * the new block, increase lower level extents' reference count.
645 * Back Reference Key composing:
647 * The key objectid corresponds to the first byte in the extent,
648 * The key type is used to differentiate between types of back refs.
649 * There are different meanings of the key offset for different types
652 * File extents can be referenced by:
654 * - multiple snapshots, subvolumes, or different generations in one subvol
655 * - different files inside a single subvolume
656 * - different offsets inside a file (bookend extents in file.c)
658 * The extent ref structure for the implicit back refs has fields for:
660 * - Objectid of the subvolume root
661 * - objectid of the file holding the reference
662 * - original offset in the file
663 * - how many bookend extents
665 * The key offset for the implicit back refs is hash of the first
668 * The extent ref structure for the full back refs has field for:
670 * - number of pointers in the tree leaf
672 * The key offset for the implicit back refs is the first byte of
675 * When a file extent is allocated, The implicit back refs is used.
676 * the fields are filled in:
678 * (root_key.objectid, inode objectid, offset in file, 1)
680 * When a file extent is removed file truncation, we find the
681 * corresponding implicit back refs and check the following fields:
683 * (btrfs_header_owner(leaf), inode objectid, offset in file)
685 * Btree extents can be referenced by:
687 * - Different subvolumes
689 * Both the implicit back refs and the full back refs for tree blocks
690 * only consist of key. The key offset for the implicit back refs is
691 * objectid of block's owner tree. The key offset for the full back refs
692 * is the first byte of parent block.
694 * When implicit back refs is used, information about the lowest key and
695 * level of the tree block are required. These information are stored in
696 * tree block info structure.
699 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
700 static int convert_extent_item_v0(struct btrfs_trans_handle *trans,
701 struct btrfs_root *root,
702 struct btrfs_path *path,
703 u64 owner, u32 extra_size)
705 struct btrfs_extent_item *item;
706 struct btrfs_extent_item_v0 *ei0;
707 struct btrfs_extent_ref_v0 *ref0;
708 struct btrfs_tree_block_info *bi;
709 struct extent_buffer *leaf;
710 struct btrfs_key key;
711 struct btrfs_key found_key;
712 u32 new_size = sizeof(*item);
716 leaf = path->nodes[0];
717 BUG_ON(btrfs_item_size_nr(leaf, path->slots[0]) != sizeof(*ei0));
719 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
720 ei0 = btrfs_item_ptr(leaf, path->slots[0],
721 struct btrfs_extent_item_v0);
722 refs = btrfs_extent_refs_v0(leaf, ei0);
724 if (owner == (u64)-1) {
726 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
727 ret = btrfs_next_leaf(root, path);
731 leaf = path->nodes[0];
733 btrfs_item_key_to_cpu(leaf, &found_key,
735 BUG_ON(key.objectid != found_key.objectid);
736 if (found_key.type != BTRFS_EXTENT_REF_V0_KEY) {
740 ref0 = btrfs_item_ptr(leaf, path->slots[0],
741 struct btrfs_extent_ref_v0);
742 owner = btrfs_ref_objectid_v0(leaf, ref0);
746 btrfs_release_path(root, path);
748 if (owner < BTRFS_FIRST_FREE_OBJECTID)
749 new_size += sizeof(*bi);
751 new_size -= sizeof(*ei0);
752 ret = btrfs_search_slot(trans, root, &key, path,
753 new_size + extra_size, 1);
758 ret = btrfs_extend_item(trans, root, path, new_size);
761 leaf = path->nodes[0];
762 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
763 btrfs_set_extent_refs(leaf, item, refs);
764 /* FIXME: get real generation */
765 btrfs_set_extent_generation(leaf, item, 0);
766 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
767 btrfs_set_extent_flags(leaf, item,
768 BTRFS_EXTENT_FLAG_TREE_BLOCK |
769 BTRFS_BLOCK_FLAG_FULL_BACKREF);
770 bi = (struct btrfs_tree_block_info *)(item + 1);
771 /* FIXME: get first key of the block */
772 memset_extent_buffer(leaf, 0, (unsigned long)bi, sizeof(*bi));
773 btrfs_set_tree_block_level(leaf, bi, (int)owner);
775 btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_DATA);
777 btrfs_mark_buffer_dirty(leaf);
782 static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
784 u32 high_crc = ~(u32)0;
785 u32 low_crc = ~(u32)0;
788 lenum = cpu_to_le64(root_objectid);
789 high_crc = crc32c(high_crc, &lenum, sizeof(lenum));
790 lenum = cpu_to_le64(owner);
791 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
792 lenum = cpu_to_le64(offset);
793 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
795 return ((u64)high_crc << 31) ^ (u64)low_crc;
798 static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
799 struct btrfs_extent_data_ref *ref)
801 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
802 btrfs_extent_data_ref_objectid(leaf, ref),
803 btrfs_extent_data_ref_offset(leaf, ref));
806 static int match_extent_data_ref(struct extent_buffer *leaf,
807 struct btrfs_extent_data_ref *ref,
808 u64 root_objectid, u64 owner, u64 offset)
810 if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
811 btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
812 btrfs_extent_data_ref_offset(leaf, ref) != offset)
817 static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
818 struct btrfs_root *root,
819 struct btrfs_path *path,
820 u64 bytenr, u64 parent,
822 u64 owner, u64 offset)
824 struct btrfs_key key;
825 struct btrfs_extent_data_ref *ref;
826 struct extent_buffer *leaf;
832 key.objectid = bytenr;
834 key.type = BTRFS_SHARED_DATA_REF_KEY;
837 key.type = BTRFS_EXTENT_DATA_REF_KEY;
838 key.offset = hash_extent_data_ref(root_objectid,
843 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
852 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
853 key.type = BTRFS_EXTENT_REF_V0_KEY;
854 btrfs_release_path(root, path);
855 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
866 leaf = path->nodes[0];
867 nritems = btrfs_header_nritems(leaf);
869 if (path->slots[0] >= nritems) {
870 ret = btrfs_next_leaf(root, path);
876 leaf = path->nodes[0];
877 nritems = btrfs_header_nritems(leaf);
881 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
882 if (key.objectid != bytenr ||
883 key.type != BTRFS_EXTENT_DATA_REF_KEY)
886 ref = btrfs_item_ptr(leaf, path->slots[0],
887 struct btrfs_extent_data_ref);
889 if (match_extent_data_ref(leaf, ref, root_objectid,
892 btrfs_release_path(root, path);
904 static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
905 struct btrfs_root *root,
906 struct btrfs_path *path,
907 u64 bytenr, u64 parent,
908 u64 root_objectid, u64 owner,
909 u64 offset, int refs_to_add)
911 struct btrfs_key key;
912 struct extent_buffer *leaf;
917 key.objectid = bytenr;
919 key.type = BTRFS_SHARED_DATA_REF_KEY;
921 size = sizeof(struct btrfs_shared_data_ref);
923 key.type = BTRFS_EXTENT_DATA_REF_KEY;
924 key.offset = hash_extent_data_ref(root_objectid,
926 size = sizeof(struct btrfs_extent_data_ref);
929 ret = btrfs_insert_empty_item(trans, root, path, &key, size);
930 if (ret && ret != -EEXIST)
933 leaf = path->nodes[0];
935 struct btrfs_shared_data_ref *ref;
936 ref = btrfs_item_ptr(leaf, path->slots[0],
937 struct btrfs_shared_data_ref);
939 btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
941 num_refs = btrfs_shared_data_ref_count(leaf, ref);
942 num_refs += refs_to_add;
943 btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
946 struct btrfs_extent_data_ref *ref;
947 while (ret == -EEXIST) {
948 ref = btrfs_item_ptr(leaf, path->slots[0],
949 struct btrfs_extent_data_ref);
950 if (match_extent_data_ref(leaf, ref, root_objectid,
953 btrfs_release_path(root, path);
955 ret = btrfs_insert_empty_item(trans, root, path, &key,
957 if (ret && ret != -EEXIST)
960 leaf = path->nodes[0];
962 ref = btrfs_item_ptr(leaf, path->slots[0],
963 struct btrfs_extent_data_ref);
965 btrfs_set_extent_data_ref_root(leaf, ref,
967 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
968 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
969 btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
971 num_refs = btrfs_extent_data_ref_count(leaf, ref);
972 num_refs += refs_to_add;
973 btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
976 btrfs_mark_buffer_dirty(leaf);
979 btrfs_release_path(root, path);
983 static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
984 struct btrfs_root *root,
985 struct btrfs_path *path,
988 struct btrfs_key key;
989 struct btrfs_extent_data_ref *ref1 = NULL;
990 struct btrfs_shared_data_ref *ref2 = NULL;
991 struct extent_buffer *leaf;
995 leaf = path->nodes[0];
996 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
998 if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
999 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1000 struct btrfs_extent_data_ref);
1001 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1002 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1003 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1004 struct btrfs_shared_data_ref);
1005 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1006 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1007 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1008 struct btrfs_extent_ref_v0 *ref0;
1009 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1010 struct btrfs_extent_ref_v0);
1011 num_refs = btrfs_ref_count_v0(leaf, ref0);
1017 BUG_ON(num_refs < refs_to_drop);
1018 num_refs -= refs_to_drop;
1020 if (num_refs == 0) {
1021 ret = btrfs_del_item(trans, root, path);
1023 if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
1024 btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
1025 else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
1026 btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
1027 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1029 struct btrfs_extent_ref_v0 *ref0;
1030 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1031 struct btrfs_extent_ref_v0);
1032 btrfs_set_ref_count_v0(leaf, ref0, num_refs);
1035 btrfs_mark_buffer_dirty(leaf);
1040 static noinline u32 extent_data_ref_count(struct btrfs_root *root,
1041 struct btrfs_path *path,
1042 struct btrfs_extent_inline_ref *iref)
1044 struct btrfs_key key;
1045 struct extent_buffer *leaf;
1046 struct btrfs_extent_data_ref *ref1;
1047 struct btrfs_shared_data_ref *ref2;
1050 leaf = path->nodes[0];
1051 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1053 if (btrfs_extent_inline_ref_type(leaf, iref) ==
1054 BTRFS_EXTENT_DATA_REF_KEY) {
1055 ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
1056 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1058 ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
1059 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1061 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
1062 ref1 = btrfs_item_ptr(leaf, path->slots[0],
1063 struct btrfs_extent_data_ref);
1064 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
1065 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
1066 ref2 = btrfs_item_ptr(leaf, path->slots[0],
1067 struct btrfs_shared_data_ref);
1068 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
1069 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1070 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
1071 struct btrfs_extent_ref_v0 *ref0;
1072 ref0 = btrfs_item_ptr(leaf, path->slots[0],
1073 struct btrfs_extent_ref_v0);
1074 num_refs = btrfs_ref_count_v0(leaf, ref0);
1082 static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
1083 struct btrfs_root *root,
1084 struct btrfs_path *path,
1085 u64 bytenr, u64 parent,
1088 struct btrfs_key key;
1091 key.objectid = bytenr;
1093 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1094 key.offset = parent;
1096 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1097 key.offset = root_objectid;
1100 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1103 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1104 if (ret == -ENOENT && parent) {
1105 btrfs_release_path(root, path);
1106 key.type = BTRFS_EXTENT_REF_V0_KEY;
1107 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1115 static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
1116 struct btrfs_root *root,
1117 struct btrfs_path *path,
1118 u64 bytenr, u64 parent,
1121 struct btrfs_key key;
1124 key.objectid = bytenr;
1126 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
1127 key.offset = parent;
1129 key.type = BTRFS_TREE_BLOCK_REF_KEY;
1130 key.offset = root_objectid;
1133 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
1134 btrfs_release_path(root, path);
1138 static inline int extent_ref_type(u64 parent, u64 owner)
1141 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1143 type = BTRFS_SHARED_BLOCK_REF_KEY;
1145 type = BTRFS_TREE_BLOCK_REF_KEY;
1148 type = BTRFS_SHARED_DATA_REF_KEY;
1150 type = BTRFS_EXTENT_DATA_REF_KEY;
1155 static int find_next_key(struct btrfs_path *path, int level,
1156 struct btrfs_key *key)
1159 for (; level < BTRFS_MAX_LEVEL; level++) {
1160 if (!path->nodes[level])
1162 if (path->slots[level] + 1 >=
1163 btrfs_header_nritems(path->nodes[level]))
1166 btrfs_item_key_to_cpu(path->nodes[level], key,
1167 path->slots[level] + 1);
1169 btrfs_node_key_to_cpu(path->nodes[level], key,
1170 path->slots[level] + 1);
1177 * look for inline back ref. if back ref is found, *ref_ret is set
1178 * to the address of inline back ref, and 0 is returned.
1180 * if back ref isn't found, *ref_ret is set to the address where it
1181 * should be inserted, and -ENOENT is returned.
1183 * if insert is true and there are too many inline back refs, the path
1184 * points to the extent item, and -EAGAIN is returned.
1186 * NOTE: inline back refs are ordered in the same way that back ref
1187 * items in the tree are ordered.
1189 static noinline_for_stack
1190 int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
1191 struct btrfs_root *root,
1192 struct btrfs_path *path,
1193 struct btrfs_extent_inline_ref **ref_ret,
1194 u64 bytenr, u64 num_bytes,
1195 u64 parent, u64 root_objectid,
1196 u64 owner, u64 offset, int insert)
1198 struct btrfs_key key;
1199 struct extent_buffer *leaf;
1200 struct btrfs_extent_item *ei;
1201 struct btrfs_extent_inline_ref *iref;
1212 key.objectid = bytenr;
1213 key.type = BTRFS_EXTENT_ITEM_KEY;
1214 key.offset = num_bytes;
1216 want = extent_ref_type(parent, owner);
1218 extra_size = btrfs_extent_inline_ref_size(want);
1219 path->keep_locks = 1;
1222 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
1229 leaf = path->nodes[0];
1230 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1231 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1232 if (item_size < sizeof(*ei)) {
1237 ret = convert_extent_item_v0(trans, root, path, owner,
1243 leaf = path->nodes[0];
1244 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1247 BUG_ON(item_size < sizeof(*ei));
1249 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1250 flags = btrfs_extent_flags(leaf, ei);
1252 ptr = (unsigned long)(ei + 1);
1253 end = (unsigned long)ei + item_size;
1255 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
1256 ptr += sizeof(struct btrfs_tree_block_info);
1259 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_DATA));
1268 iref = (struct btrfs_extent_inline_ref *)ptr;
1269 type = btrfs_extent_inline_ref_type(leaf, iref);
1273 ptr += btrfs_extent_inline_ref_size(type);
1277 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1278 struct btrfs_extent_data_ref *dref;
1279 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1280 if (match_extent_data_ref(leaf, dref, root_objectid,
1285 if (hash_extent_data_ref_item(leaf, dref) <
1286 hash_extent_data_ref(root_objectid, owner, offset))
1290 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1292 if (parent == ref_offset) {
1296 if (ref_offset < parent)
1299 if (root_objectid == ref_offset) {
1303 if (ref_offset < root_objectid)
1307 ptr += btrfs_extent_inline_ref_size(type);
1309 if (err == -ENOENT && insert) {
1310 if (item_size + extra_size >=
1311 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
1316 * To add new inline back ref, we have to make sure
1317 * there is no corresponding back ref item.
1318 * For simplicity, we just do not add new inline back
1319 * ref if there is any kind of item for this block
1321 if (find_next_key(path, 0, &key) == 0 &&
1322 key.objectid == bytenr &&
1323 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
1328 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
1331 path->keep_locks = 0;
1332 btrfs_unlock_up_safe(path, 1);
1338 * helper to add new inline back ref
1340 static noinline_for_stack
1341 int setup_inline_extent_backref(struct btrfs_trans_handle *trans,
1342 struct btrfs_root *root,
1343 struct btrfs_path *path,
1344 struct btrfs_extent_inline_ref *iref,
1345 u64 parent, u64 root_objectid,
1346 u64 owner, u64 offset, int refs_to_add,
1347 struct btrfs_delayed_extent_op *extent_op)
1349 struct extent_buffer *leaf;
1350 struct btrfs_extent_item *ei;
1353 unsigned long item_offset;
1359 leaf = path->nodes[0];
1360 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1361 item_offset = (unsigned long)iref - (unsigned long)ei;
1363 type = extent_ref_type(parent, owner);
1364 size = btrfs_extent_inline_ref_size(type);
1366 ret = btrfs_extend_item(trans, root, path, size);
1369 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1370 refs = btrfs_extent_refs(leaf, ei);
1371 refs += refs_to_add;
1372 btrfs_set_extent_refs(leaf, ei, refs);
1374 __run_delayed_extent_op(extent_op, leaf, ei);
1376 ptr = (unsigned long)ei + item_offset;
1377 end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
1378 if (ptr < end - size)
1379 memmove_extent_buffer(leaf, ptr + size, ptr,
1382 iref = (struct btrfs_extent_inline_ref *)ptr;
1383 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1384 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1385 struct btrfs_extent_data_ref *dref;
1386 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1387 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1388 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1389 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1390 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1391 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1392 struct btrfs_shared_data_ref *sref;
1393 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1394 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1395 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1396 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1397 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1399 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1401 btrfs_mark_buffer_dirty(leaf);
1405 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1406 struct btrfs_root *root,
1407 struct btrfs_path *path,
1408 struct btrfs_extent_inline_ref **ref_ret,
1409 u64 bytenr, u64 num_bytes, u64 parent,
1410 u64 root_objectid, u64 owner, u64 offset)
1414 ret = lookup_inline_extent_backref(trans, root, path, ref_ret,
1415 bytenr, num_bytes, parent,
1416 root_objectid, owner, offset, 0);
1420 btrfs_release_path(root, path);
1423 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1424 ret = lookup_tree_block_ref(trans, root, path, bytenr, parent,
1427 ret = lookup_extent_data_ref(trans, root, path, bytenr, parent,
1428 root_objectid, owner, offset);
1434 * helper to update/remove inline back ref
1436 static noinline_for_stack
1437 int update_inline_extent_backref(struct btrfs_trans_handle *trans,
1438 struct btrfs_root *root,
1439 struct btrfs_path *path,
1440 struct btrfs_extent_inline_ref *iref,
1442 struct btrfs_delayed_extent_op *extent_op)
1444 struct extent_buffer *leaf;
1445 struct btrfs_extent_item *ei;
1446 struct btrfs_extent_data_ref *dref = NULL;
1447 struct btrfs_shared_data_ref *sref = NULL;
1456 leaf = path->nodes[0];
1457 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1458 refs = btrfs_extent_refs(leaf, ei);
1459 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1460 refs += refs_to_mod;
1461 btrfs_set_extent_refs(leaf, ei, refs);
1463 __run_delayed_extent_op(extent_op, leaf, ei);
1465 type = btrfs_extent_inline_ref_type(leaf, iref);
1467 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1468 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1469 refs = btrfs_extent_data_ref_count(leaf, dref);
1470 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1471 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1472 refs = btrfs_shared_data_ref_count(leaf, sref);
1475 BUG_ON(refs_to_mod != -1);
1478 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1479 refs += refs_to_mod;
1482 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1483 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1485 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1487 size = btrfs_extent_inline_ref_size(type);
1488 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1489 ptr = (unsigned long)iref;
1490 end = (unsigned long)ei + item_size;
1491 if (ptr + size < end)
1492 memmove_extent_buffer(leaf, ptr, ptr + size,
1495 ret = btrfs_truncate_item(trans, root, path, item_size, 1);
1498 btrfs_mark_buffer_dirty(leaf);
1502 static noinline_for_stack
1503 int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1504 struct btrfs_root *root,
1505 struct btrfs_path *path,
1506 u64 bytenr, u64 num_bytes, u64 parent,
1507 u64 root_objectid, u64 owner,
1508 u64 offset, int refs_to_add,
1509 struct btrfs_delayed_extent_op *extent_op)
1511 struct btrfs_extent_inline_ref *iref;
1514 ret = lookup_inline_extent_backref(trans, root, path, &iref,
1515 bytenr, num_bytes, parent,
1516 root_objectid, owner, offset, 1);
1518 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
1519 ret = update_inline_extent_backref(trans, root, path, iref,
1520 refs_to_add, extent_op);
1521 } else if (ret == -ENOENT) {
1522 ret = setup_inline_extent_backref(trans, root, path, iref,
1523 parent, root_objectid,
1524 owner, offset, refs_to_add,
1530 static int insert_extent_backref(struct btrfs_trans_handle *trans,
1531 struct btrfs_root *root,
1532 struct btrfs_path *path,
1533 u64 bytenr, u64 parent, u64 root_objectid,
1534 u64 owner, u64 offset, int refs_to_add)
1537 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1538 BUG_ON(refs_to_add != 1);
1539 ret = insert_tree_block_ref(trans, root, path, bytenr,
1540 parent, root_objectid);
1542 ret = insert_extent_data_ref(trans, root, path, bytenr,
1543 parent, root_objectid,
1544 owner, offset, refs_to_add);
1549 static int remove_extent_backref(struct btrfs_trans_handle *trans,
1550 struct btrfs_root *root,
1551 struct btrfs_path *path,
1552 struct btrfs_extent_inline_ref *iref,
1553 int refs_to_drop, int is_data)
1557 BUG_ON(!is_data && refs_to_drop != 1);
1559 ret = update_inline_extent_backref(trans, root, path, iref,
1560 -refs_to_drop, NULL);
1561 } else if (is_data) {
1562 ret = remove_extent_data_ref(trans, root, path, refs_to_drop);
1564 ret = btrfs_del_item(trans, root, path);
1569 #ifdef BIO_RW_DISCARD
1570 static void btrfs_issue_discard(struct block_device *bdev,
1573 blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_KERNEL);
1577 static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
1580 #ifdef BIO_RW_DISCARD
1582 u64 map_length = num_bytes;
1583 struct btrfs_multi_bio *multi = NULL;
1585 /* Tell the block device(s) that the sectors can be discarded */
1586 ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
1587 bytenr, &map_length, &multi, 0);
1589 struct btrfs_bio_stripe *stripe = multi->stripes;
1592 if (map_length > num_bytes)
1593 map_length = num_bytes;
1595 for (i = 0; i < multi->num_stripes; i++, stripe++) {
1596 btrfs_issue_discard(stripe->dev->bdev,
1609 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1610 struct btrfs_root *root,
1611 u64 bytenr, u64 num_bytes, u64 parent,
1612 u64 root_objectid, u64 owner, u64 offset)
1615 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID &&
1616 root_objectid == BTRFS_TREE_LOG_OBJECTID);
1618 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1619 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
1620 parent, root_objectid, (int)owner,
1621 BTRFS_ADD_DELAYED_REF, NULL);
1623 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
1624 parent, root_objectid, owner, offset,
1625 BTRFS_ADD_DELAYED_REF, NULL);
1630 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1631 struct btrfs_root *root,
1632 u64 bytenr, u64 num_bytes,
1633 u64 parent, u64 root_objectid,
1634 u64 owner, u64 offset, int refs_to_add,
1635 struct btrfs_delayed_extent_op *extent_op)
1637 struct btrfs_path *path;
1638 struct extent_buffer *leaf;
1639 struct btrfs_extent_item *item;
1644 path = btrfs_alloc_path();
1649 path->leave_spinning = 1;
1650 /* this will setup the path even if it fails to insert the back ref */
1651 ret = insert_inline_extent_backref(trans, root->fs_info->extent_root,
1652 path, bytenr, num_bytes, parent,
1653 root_objectid, owner, offset,
1654 refs_to_add, extent_op);
1658 if (ret != -EAGAIN) {
1663 leaf = path->nodes[0];
1664 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1665 refs = btrfs_extent_refs(leaf, item);
1666 btrfs_set_extent_refs(leaf, item, refs + refs_to_add);
1668 __run_delayed_extent_op(extent_op, leaf, item);
1670 btrfs_mark_buffer_dirty(leaf);
1671 btrfs_release_path(root->fs_info->extent_root, path);
1674 path->leave_spinning = 1;
1676 /* now insert the actual backref */
1677 ret = insert_extent_backref(trans, root->fs_info->extent_root,
1678 path, bytenr, parent, root_objectid,
1679 owner, offset, refs_to_add);
1682 btrfs_free_path(path);
1686 static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
1687 struct btrfs_root *root,
1688 struct btrfs_delayed_ref_node *node,
1689 struct btrfs_delayed_extent_op *extent_op,
1690 int insert_reserved)
1693 struct btrfs_delayed_data_ref *ref;
1694 struct btrfs_key ins;
1699 ins.objectid = node->bytenr;
1700 ins.offset = node->num_bytes;
1701 ins.type = BTRFS_EXTENT_ITEM_KEY;
1703 ref = btrfs_delayed_node_to_data_ref(node);
1704 if (node->type == BTRFS_SHARED_DATA_REF_KEY)
1705 parent = ref->parent;
1707 ref_root = ref->root;
1709 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
1711 BUG_ON(extent_op->update_key);
1712 flags |= extent_op->flags_to_set;
1714 ret = alloc_reserved_file_extent(trans, root,
1715 parent, ref_root, flags,
1716 ref->objectid, ref->offset,
1717 &ins, node->ref_mod);
1718 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
1719 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
1720 node->num_bytes, parent,
1721 ref_root, ref->objectid,
1722 ref->offset, node->ref_mod,
1724 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
1725 ret = __btrfs_free_extent(trans, root, node->bytenr,
1726 node->num_bytes, parent,
1727 ref_root, ref->objectid,
1728 ref->offset, node->ref_mod,
1736 static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
1737 struct extent_buffer *leaf,
1738 struct btrfs_extent_item *ei)
1740 u64 flags = btrfs_extent_flags(leaf, ei);
1741 if (extent_op->update_flags) {
1742 flags |= extent_op->flags_to_set;
1743 btrfs_set_extent_flags(leaf, ei, flags);
1746 if (extent_op->update_key) {
1747 struct btrfs_tree_block_info *bi;
1748 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK));
1749 bi = (struct btrfs_tree_block_info *)(ei + 1);
1750 btrfs_set_tree_block_key(leaf, bi, &extent_op->key);
1754 static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
1755 struct btrfs_root *root,
1756 struct btrfs_delayed_ref_node *node,
1757 struct btrfs_delayed_extent_op *extent_op)
1759 struct btrfs_key key;
1760 struct btrfs_path *path;
1761 struct btrfs_extent_item *ei;
1762 struct extent_buffer *leaf;
1767 path = btrfs_alloc_path();
1771 key.objectid = node->bytenr;
1772 key.type = BTRFS_EXTENT_ITEM_KEY;
1773 key.offset = node->num_bytes;
1776 path->leave_spinning = 1;
1777 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key,
1788 leaf = path->nodes[0];
1789 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1790 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1791 if (item_size < sizeof(*ei)) {
1792 ret = convert_extent_item_v0(trans, root->fs_info->extent_root,
1798 leaf = path->nodes[0];
1799 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1802 BUG_ON(item_size < sizeof(*ei));
1803 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1804 __run_delayed_extent_op(extent_op, leaf, ei);
1806 btrfs_mark_buffer_dirty(leaf);
1808 btrfs_free_path(path);
1812 static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
1813 struct btrfs_root *root,
1814 struct btrfs_delayed_ref_node *node,
1815 struct btrfs_delayed_extent_op *extent_op,
1816 int insert_reserved)
1819 struct btrfs_delayed_tree_ref *ref;
1820 struct btrfs_key ins;
1824 ins.objectid = node->bytenr;
1825 ins.offset = node->num_bytes;
1826 ins.type = BTRFS_EXTENT_ITEM_KEY;
1828 ref = btrfs_delayed_node_to_tree_ref(node);
1829 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
1830 parent = ref->parent;
1832 ref_root = ref->root;
1834 BUG_ON(node->ref_mod != 1);
1835 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
1836 BUG_ON(!extent_op || !extent_op->update_flags ||
1837 !extent_op->update_key);
1838 ret = alloc_reserved_tree_block(trans, root,
1840 extent_op->flags_to_set,
1843 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
1844 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
1845 node->num_bytes, parent, ref_root,
1846 ref->level, 0, 1, extent_op);
1847 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
1848 ret = __btrfs_free_extent(trans, root, node->bytenr,
1849 node->num_bytes, parent, ref_root,
1850 ref->level, 0, 1, extent_op);
1858 /* helper function to actually process a single delayed ref entry */
1859 static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
1860 struct btrfs_root *root,
1861 struct btrfs_delayed_ref_node *node,
1862 struct btrfs_delayed_extent_op *extent_op,
1863 int insert_reserved)
1866 if (btrfs_delayed_ref_is_head(node)) {
1867 struct btrfs_delayed_ref_head *head;
1869 * we've hit the end of the chain and we were supposed
1870 * to insert this extent into the tree. But, it got
1871 * deleted before we ever needed to insert it, so all
1872 * we have to do is clean up the accounting
1875 head = btrfs_delayed_node_to_head(node);
1876 if (insert_reserved) {
1878 struct extent_buffer *must_clean = NULL;
1880 ret = pin_down_bytes(trans, root, NULL,
1881 node->bytenr, node->num_bytes,
1882 head->is_data, 1, &must_clean);
1887 clean_tree_block(NULL, root, must_clean);
1888 btrfs_tree_unlock(must_clean);
1889 free_extent_buffer(must_clean);
1891 if (head->is_data) {
1892 ret = btrfs_del_csums(trans, root,
1898 ret = btrfs_free_reserved_extent(root,
1904 mutex_unlock(&head->mutex);
1908 if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
1909 node->type == BTRFS_SHARED_BLOCK_REF_KEY)
1910 ret = run_delayed_tree_ref(trans, root, node, extent_op,
1912 else if (node->type == BTRFS_EXTENT_DATA_REF_KEY ||
1913 node->type == BTRFS_SHARED_DATA_REF_KEY)
1914 ret = run_delayed_data_ref(trans, root, node, extent_op,
1921 static noinline struct btrfs_delayed_ref_node *
1922 select_delayed_ref(struct btrfs_delayed_ref_head *head)
1924 struct rb_node *node;
1925 struct btrfs_delayed_ref_node *ref;
1926 int action = BTRFS_ADD_DELAYED_REF;
1929 * select delayed ref of type BTRFS_ADD_DELAYED_REF first.
1930 * this prevents ref count from going down to zero when
1931 * there still are pending delayed ref.
1933 node = rb_prev(&head->node.rb_node);
1937 ref = rb_entry(node, struct btrfs_delayed_ref_node,
1939 if (ref->bytenr != head->node.bytenr)
1941 if (ref->action == action)
1943 node = rb_prev(node);
1945 if (action == BTRFS_ADD_DELAYED_REF) {
1946 action = BTRFS_DROP_DELAYED_REF;
1952 static noinline int run_clustered_refs(struct btrfs_trans_handle *trans,
1953 struct btrfs_root *root,
1954 struct list_head *cluster)
1956 struct btrfs_delayed_ref_root *delayed_refs;
1957 struct btrfs_delayed_ref_node *ref;
1958 struct btrfs_delayed_ref_head *locked_ref = NULL;
1959 struct btrfs_delayed_extent_op *extent_op;
1962 int must_insert_reserved = 0;
1964 delayed_refs = &trans->transaction->delayed_refs;
1967 /* pick a new head ref from the cluster list */
1968 if (list_empty(cluster))
1971 locked_ref = list_entry(cluster->next,
1972 struct btrfs_delayed_ref_head, cluster);
1974 /* grab the lock that says we are going to process
1975 * all the refs for this head */
1976 ret = btrfs_delayed_ref_lock(trans, locked_ref);
1979 * we may have dropped the spin lock to get the head
1980 * mutex lock, and that might have given someone else
1981 * time to free the head. If that's true, it has been
1982 * removed from our list and we can move on.
1984 if (ret == -EAGAIN) {
1992 * record the must insert reserved flag before we
1993 * drop the spin lock.
1995 must_insert_reserved = locked_ref->must_insert_reserved;
1996 locked_ref->must_insert_reserved = 0;
1998 extent_op = locked_ref->extent_op;
1999 locked_ref->extent_op = NULL;
2002 * locked_ref is the head node, so we have to go one
2003 * node back for any delayed ref updates
2005 ref = select_delayed_ref(locked_ref);
2007 /* All delayed refs have been processed, Go ahead
2008 * and send the head node to run_one_delayed_ref,
2009 * so that any accounting fixes can happen
2011 ref = &locked_ref->node;
2013 if (extent_op && must_insert_reserved) {
2019 spin_unlock(&delayed_refs->lock);
2021 ret = run_delayed_extent_op(trans, root,
2027 spin_lock(&delayed_refs->lock);
2031 list_del_init(&locked_ref->cluster);
2036 rb_erase(&ref->rb_node, &delayed_refs->root);
2037 delayed_refs->num_entries--;
2039 spin_unlock(&delayed_refs->lock);
2041 ret = run_one_delayed_ref(trans, root, ref, extent_op,
2042 must_insert_reserved);
2045 btrfs_put_delayed_ref(ref);
2050 spin_lock(&delayed_refs->lock);
2056 * this starts processing the delayed reference count updates and
2057 * extent insertions we have queued up so far. count can be
2058 * 0, which means to process everything in the tree at the start
2059 * of the run (but not newly added entries), or it can be some target
2060 * number you'd like to process.
2062 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
2063 struct btrfs_root *root, unsigned long count)
2065 struct rb_node *node;
2066 struct btrfs_delayed_ref_root *delayed_refs;
2067 struct btrfs_delayed_ref_node *ref;
2068 struct list_head cluster;
2070 int run_all = count == (unsigned long)-1;
2073 if (root == root->fs_info->extent_root)
2074 root = root->fs_info->tree_root;
2076 delayed_refs = &trans->transaction->delayed_refs;
2077 INIT_LIST_HEAD(&cluster);
2079 spin_lock(&delayed_refs->lock);
2081 count = delayed_refs->num_entries * 2;
2085 if (!(run_all || run_most) &&
2086 delayed_refs->num_heads_ready < 64)
2090 * go find something we can process in the rbtree. We start at
2091 * the beginning of the tree, and then build a cluster
2092 * of refs to process starting at the first one we are able to
2095 ret = btrfs_find_ref_cluster(trans, &cluster,
2096 delayed_refs->run_delayed_start);
2100 ret = run_clustered_refs(trans, root, &cluster);
2103 count -= min_t(unsigned long, ret, count);
2110 node = rb_first(&delayed_refs->root);
2113 count = (unsigned long)-1;
2116 ref = rb_entry(node, struct btrfs_delayed_ref_node,
2118 if (btrfs_delayed_ref_is_head(ref)) {
2119 struct btrfs_delayed_ref_head *head;
2121 head = btrfs_delayed_node_to_head(ref);
2122 atomic_inc(&ref->refs);
2124 spin_unlock(&delayed_refs->lock);
2125 mutex_lock(&head->mutex);
2126 mutex_unlock(&head->mutex);
2128 btrfs_put_delayed_ref(ref);
2132 node = rb_next(node);
2134 spin_unlock(&delayed_refs->lock);
2135 schedule_timeout(1);
2139 spin_unlock(&delayed_refs->lock);
2143 int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
2144 struct btrfs_root *root,
2145 u64 bytenr, u64 num_bytes, u64 flags,
2148 struct btrfs_delayed_extent_op *extent_op;
2151 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
2155 extent_op->flags_to_set = flags;
2156 extent_op->update_flags = 1;
2157 extent_op->update_key = 0;
2158 extent_op->is_data = is_data ? 1 : 0;
2160 ret = btrfs_add_delayed_extent_op(trans, bytenr, num_bytes, extent_op);
2166 static noinline int check_delayed_ref(struct btrfs_trans_handle *trans,
2167 struct btrfs_root *root,
2168 struct btrfs_path *path,
2169 u64 objectid, u64 offset, u64 bytenr)
2171 struct btrfs_delayed_ref_head *head;
2172 struct btrfs_delayed_ref_node *ref;
2173 struct btrfs_delayed_data_ref *data_ref;
2174 struct btrfs_delayed_ref_root *delayed_refs;
2175 struct rb_node *node;
2179 delayed_refs = &trans->transaction->delayed_refs;
2180 spin_lock(&delayed_refs->lock);
2181 head = btrfs_find_delayed_ref_head(trans, bytenr);
2185 if (!mutex_trylock(&head->mutex)) {
2186 atomic_inc(&head->node.refs);
2187 spin_unlock(&delayed_refs->lock);
2189 btrfs_release_path(root->fs_info->extent_root, path);
2191 mutex_lock(&head->mutex);
2192 mutex_unlock(&head->mutex);
2193 btrfs_put_delayed_ref(&head->node);
2197 node = rb_prev(&head->node.rb_node);
2201 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2203 if (ref->bytenr != bytenr)
2207 if (ref->type != BTRFS_EXTENT_DATA_REF_KEY)
2210 data_ref = btrfs_delayed_node_to_data_ref(ref);
2212 node = rb_prev(node);
2214 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2215 if (ref->bytenr == bytenr)
2219 if (data_ref->root != root->root_key.objectid ||
2220 data_ref->objectid != objectid || data_ref->offset != offset)
2225 mutex_unlock(&head->mutex);
2227 spin_unlock(&delayed_refs->lock);
2231 static noinline int check_committed_ref(struct btrfs_trans_handle *trans,
2232 struct btrfs_root *root,
2233 struct btrfs_path *path,
2234 u64 objectid, u64 offset, u64 bytenr)
2236 struct btrfs_root *extent_root = root->fs_info->extent_root;
2237 struct extent_buffer *leaf;
2238 struct btrfs_extent_data_ref *ref;
2239 struct btrfs_extent_inline_ref *iref;
2240 struct btrfs_extent_item *ei;
2241 struct btrfs_key key;
2245 key.objectid = bytenr;
2246 key.offset = (u64)-1;
2247 key.type = BTRFS_EXTENT_ITEM_KEY;
2249 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
2255 if (path->slots[0] == 0)
2259 leaf = path->nodes[0];
2260 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2262 if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY)
2266 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2267 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2268 if (item_size < sizeof(*ei)) {
2269 WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0));
2273 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
2275 if (item_size != sizeof(*ei) +
2276 btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY))
2279 if (btrfs_extent_generation(leaf, ei) <=
2280 btrfs_root_last_snapshot(&root->root_item))
2283 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
2284 if (btrfs_extent_inline_ref_type(leaf, iref) !=
2285 BTRFS_EXTENT_DATA_REF_KEY)
2288 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
2289 if (btrfs_extent_refs(leaf, ei) !=
2290 btrfs_extent_data_ref_count(leaf, ref) ||
2291 btrfs_extent_data_ref_root(leaf, ref) !=
2292 root->root_key.objectid ||
2293 btrfs_extent_data_ref_objectid(leaf, ref) != objectid ||
2294 btrfs_extent_data_ref_offset(leaf, ref) != offset)
2302 int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans,
2303 struct btrfs_root *root,
2304 u64 objectid, u64 offset, u64 bytenr)
2306 struct btrfs_path *path;
2310 path = btrfs_alloc_path();
2315 ret = check_committed_ref(trans, root, path, objectid,
2317 if (ret && ret != -ENOENT)
2320 ret2 = check_delayed_ref(trans, root, path, objectid,
2322 } while (ret2 == -EAGAIN);
2324 if (ret2 && ret2 != -ENOENT) {
2329 if (ret != -ENOENT || ret2 != -ENOENT)
2332 btrfs_free_path(path);
2337 int btrfs_cache_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2338 struct extent_buffer *buf, u32 nr_extents)
2340 struct btrfs_key key;
2341 struct btrfs_file_extent_item *fi;
2349 if (!root->ref_cows)
2352 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
2354 root_gen = root->root_key.offset;
2357 root_gen = trans->transid - 1;
2360 level = btrfs_header_level(buf);
2361 nritems = btrfs_header_nritems(buf);
2364 struct btrfs_leaf_ref *ref;
2365 struct btrfs_extent_info *info;
2367 ref = btrfs_alloc_leaf_ref(root, nr_extents);
2373 ref->root_gen = root_gen;
2374 ref->bytenr = buf->start;
2375 ref->owner = btrfs_header_owner(buf);
2376 ref->generation = btrfs_header_generation(buf);
2377 ref->nritems = nr_extents;
2378 info = ref->extents;
2380 for (i = 0; nr_extents > 0 && i < nritems; i++) {
2382 btrfs_item_key_to_cpu(buf, &key, i);
2383 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2385 fi = btrfs_item_ptr(buf, i,
2386 struct btrfs_file_extent_item);
2387 if (btrfs_file_extent_type(buf, fi) ==
2388 BTRFS_FILE_EXTENT_INLINE)
2390 disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2391 if (disk_bytenr == 0)
2394 info->bytenr = disk_bytenr;
2396 btrfs_file_extent_disk_num_bytes(buf, fi);
2397 info->objectid = key.objectid;
2398 info->offset = key.offset;
2402 ret = btrfs_add_leaf_ref(root, ref, shared);
2403 if (ret == -EEXIST && shared) {
2404 struct btrfs_leaf_ref *old;
2405 old = btrfs_lookup_leaf_ref(root, ref->bytenr);
2407 btrfs_remove_leaf_ref(root, old);
2408 btrfs_free_leaf_ref(root, old);
2409 ret = btrfs_add_leaf_ref(root, ref, shared);
2412 btrfs_free_leaf_ref(root, ref);
2418 /* when a block goes through cow, we update the reference counts of
2419 * everything that block points to. The internal pointers of the block
2420 * can be in just about any order, and it is likely to have clusters of
2421 * things that are close together and clusters of things that are not.
2423 * To help reduce the seeks that come with updating all of these reference
2424 * counts, sort them by byte number before actual updates are done.
2426 * struct refsort is used to match byte number to slot in the btree block.
2427 * we sort based on the byte number and then use the slot to actually
2430 * struct refsort is smaller than strcut btrfs_item and smaller than
2431 * struct btrfs_key_ptr. Since we're currently limited to the page size
2432 * for a btree block, there's no way for a kmalloc of refsorts for a
2433 * single node to be bigger than a page.
2441 * for passing into sort()
2443 static int refsort_cmp(const void *a_void, const void *b_void)
2445 const struct refsort *a = a_void;
2446 const struct refsort *b = b_void;
2448 if (a->bytenr < b->bytenr)
2450 if (a->bytenr > b->bytenr)
2456 static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
2457 struct btrfs_root *root,
2458 struct extent_buffer *buf,
2459 int full_backref, int inc)
2466 struct btrfs_key key;
2467 struct btrfs_file_extent_item *fi;
2471 int (*process_func)(struct btrfs_trans_handle *, struct btrfs_root *,
2472 u64, u64, u64, u64, u64, u64);
2474 ref_root = btrfs_header_owner(buf);
2475 nritems = btrfs_header_nritems(buf);
2476 level = btrfs_header_level(buf);
2478 if (!root->ref_cows && level == 0)
2482 process_func = btrfs_inc_extent_ref;
2484 process_func = btrfs_free_extent;
2487 parent = buf->start;
2491 for (i = 0; i < nritems; i++) {
2493 btrfs_item_key_to_cpu(buf, &key, i);
2494 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2496 fi = btrfs_item_ptr(buf, i,
2497 struct btrfs_file_extent_item);
2498 if (btrfs_file_extent_type(buf, fi) ==
2499 BTRFS_FILE_EXTENT_INLINE)
2501 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2505 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
2506 key.offset -= btrfs_file_extent_offset(buf, fi);
2507 ret = process_func(trans, root, bytenr, num_bytes,
2508 parent, ref_root, key.objectid,
2513 bytenr = btrfs_node_blockptr(buf, i);
2514 num_bytes = btrfs_level_size(root, level - 1);
2515 ret = process_func(trans, root, bytenr, num_bytes,
2516 parent, ref_root, level - 1, 0);
2527 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2528 struct extent_buffer *buf, int full_backref)
2530 return __btrfs_mod_ref(trans, root, buf, full_backref, 1);
2533 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2534 struct extent_buffer *buf, int full_backref)
2536 return __btrfs_mod_ref(trans, root, buf, full_backref, 0);
2539 static int write_one_cache_group(struct btrfs_trans_handle *trans,
2540 struct btrfs_root *root,
2541 struct btrfs_path *path,
2542 struct btrfs_block_group_cache *cache)
2545 struct btrfs_root *extent_root = root->fs_info->extent_root;
2547 struct extent_buffer *leaf;
2549 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
2554 leaf = path->nodes[0];
2555 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
2556 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
2557 btrfs_mark_buffer_dirty(leaf);
2558 btrfs_release_path(extent_root, path);
2566 static struct btrfs_block_group_cache *
2567 next_block_group(struct btrfs_root *root,
2568 struct btrfs_block_group_cache *cache)
2570 struct rb_node *node;
2571 spin_lock(&root->fs_info->block_group_cache_lock);
2572 node = rb_next(&cache->cache_node);
2573 btrfs_put_block_group(cache);
2575 cache = rb_entry(node, struct btrfs_block_group_cache,
2577 atomic_inc(&cache->count);
2580 spin_unlock(&root->fs_info->block_group_cache_lock);
2584 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
2585 struct btrfs_root *root)
2587 struct btrfs_block_group_cache *cache;
2589 struct btrfs_path *path;
2592 path = btrfs_alloc_path();
2598 err = btrfs_run_delayed_refs(trans, root,
2603 cache = btrfs_lookup_first_block_group(root->fs_info, last);
2607 cache = next_block_group(root, cache);
2617 last = cache->key.objectid + cache->key.offset;
2619 err = write_one_cache_group(trans, root, path, cache);
2621 btrfs_put_block_group(cache);
2624 btrfs_free_path(path);
2628 int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr)
2630 struct btrfs_block_group_cache *block_group;
2633 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
2634 if (!block_group || block_group->ro)
2637 btrfs_put_block_group(block_group);
2641 static int update_space_info(struct btrfs_fs_info *info, u64 flags,
2642 u64 total_bytes, u64 bytes_used,
2643 struct btrfs_space_info **space_info)
2645 struct btrfs_space_info *found;
2647 found = __find_space_info(info, flags);
2649 spin_lock(&found->lock);
2650 found->total_bytes += total_bytes;
2651 found->bytes_used += bytes_used;
2653 spin_unlock(&found->lock);
2654 *space_info = found;
2657 found = kzalloc(sizeof(*found), GFP_NOFS);
2661 INIT_LIST_HEAD(&found->block_groups);
2662 init_rwsem(&found->groups_sem);
2663 spin_lock_init(&found->lock);
2664 found->flags = flags;
2665 found->total_bytes = total_bytes;
2666 found->bytes_used = bytes_used;
2667 found->bytes_pinned = 0;
2668 found->bytes_reserved = 0;
2669 found->bytes_readonly = 0;
2670 found->bytes_delalloc = 0;
2672 found->force_alloc = 0;
2673 *space_info = found;
2674 list_add_rcu(&found->list, &info->space_info);
2675 atomic_set(&found->caching_threads, 0);
2679 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
2681 u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 |
2682 BTRFS_BLOCK_GROUP_RAID1 |
2683 BTRFS_BLOCK_GROUP_RAID10 |
2684 BTRFS_BLOCK_GROUP_DUP);
2686 if (flags & BTRFS_BLOCK_GROUP_DATA)
2687 fs_info->avail_data_alloc_bits |= extra_flags;
2688 if (flags & BTRFS_BLOCK_GROUP_METADATA)
2689 fs_info->avail_metadata_alloc_bits |= extra_flags;
2690 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
2691 fs_info->avail_system_alloc_bits |= extra_flags;
2695 static void set_block_group_readonly(struct btrfs_block_group_cache *cache)
2697 spin_lock(&cache->space_info->lock);
2698 spin_lock(&cache->lock);
2700 cache->space_info->bytes_readonly += cache->key.offset -
2701 btrfs_block_group_used(&cache->item);
2704 spin_unlock(&cache->lock);
2705 spin_unlock(&cache->space_info->lock);
2708 u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
2710 u64 num_devices = root->fs_info->fs_devices->rw_devices;
2712 if (num_devices == 1)
2713 flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0);
2714 if (num_devices < 4)
2715 flags &= ~BTRFS_BLOCK_GROUP_RAID10;
2717 if ((flags & BTRFS_BLOCK_GROUP_DUP) &&
2718 (flags & (BTRFS_BLOCK_GROUP_RAID1 |
2719 BTRFS_BLOCK_GROUP_RAID10))) {
2720 flags &= ~BTRFS_BLOCK_GROUP_DUP;
2723 if ((flags & BTRFS_BLOCK_GROUP_RAID1) &&
2724 (flags & BTRFS_BLOCK_GROUP_RAID10)) {
2725 flags &= ~BTRFS_BLOCK_GROUP_RAID1;
2728 if ((flags & BTRFS_BLOCK_GROUP_RAID0) &&
2729 ((flags & BTRFS_BLOCK_GROUP_RAID1) |
2730 (flags & BTRFS_BLOCK_GROUP_RAID10) |
2731 (flags & BTRFS_BLOCK_GROUP_DUP)))
2732 flags &= ~BTRFS_BLOCK_GROUP_RAID0;
2736 static u64 btrfs_get_alloc_profile(struct btrfs_root *root, u64 data)
2738 struct btrfs_fs_info *info = root->fs_info;
2742 alloc_profile = info->avail_data_alloc_bits &
2743 info->data_alloc_profile;
2744 data = BTRFS_BLOCK_GROUP_DATA | alloc_profile;
2745 } else if (root == root->fs_info->chunk_root) {
2746 alloc_profile = info->avail_system_alloc_bits &
2747 info->system_alloc_profile;
2748 data = BTRFS_BLOCK_GROUP_SYSTEM | alloc_profile;
2750 alloc_profile = info->avail_metadata_alloc_bits &
2751 info->metadata_alloc_profile;
2752 data = BTRFS_BLOCK_GROUP_METADATA | alloc_profile;
2755 return btrfs_reduce_alloc_profile(root, data);
2758 void btrfs_set_inode_space_info(struct btrfs_root *root, struct inode *inode)
2762 alloc_target = btrfs_get_alloc_profile(root, 1);
2763 BTRFS_I(inode)->space_info = __find_space_info(root->fs_info,
2768 * for now this just makes sure we have at least 5% of our metadata space free
2771 int btrfs_check_metadata_free_space(struct btrfs_root *root)
2773 struct btrfs_fs_info *info = root->fs_info;
2774 struct btrfs_space_info *meta_sinfo;
2775 u64 alloc_target, thresh;
2776 int committed = 0, ret;
2778 /* get the space info for where the metadata will live */
2779 alloc_target = btrfs_get_alloc_profile(root, 0);
2780 meta_sinfo = __find_space_info(info, alloc_target);
2783 spin_lock(&meta_sinfo->lock);
2784 if (!meta_sinfo->full)
2785 thresh = meta_sinfo->total_bytes * 80;
2787 thresh = meta_sinfo->total_bytes * 95;
2789 do_div(thresh, 100);
2791 if (meta_sinfo->bytes_used + meta_sinfo->bytes_reserved +
2792 meta_sinfo->bytes_pinned + meta_sinfo->bytes_readonly +
2793 meta_sinfo->bytes_super > thresh) {
2794 struct btrfs_trans_handle *trans;
2795 if (!meta_sinfo->full) {
2796 meta_sinfo->force_alloc = 1;
2797 spin_unlock(&meta_sinfo->lock);
2799 trans = btrfs_start_transaction(root, 1);
2803 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
2804 2 * 1024 * 1024, alloc_target, 0);
2805 btrfs_end_transaction(trans, root);
2808 spin_unlock(&meta_sinfo->lock);
2812 trans = btrfs_join_transaction(root, 1);
2815 ret = btrfs_commit_transaction(trans, root);
2822 spin_unlock(&meta_sinfo->lock);
2828 * This will check the space that the inode allocates from to make sure we have
2829 * enough space for bytes.
2831 int btrfs_check_data_free_space(struct btrfs_root *root, struct inode *inode,
2834 struct btrfs_space_info *data_sinfo;
2835 int ret = 0, committed = 0;
2837 /* make sure bytes are sectorsize aligned */
2838 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
2840 data_sinfo = BTRFS_I(inode)->space_info;
2842 /* make sure we have enough space to handle the data first */
2843 spin_lock(&data_sinfo->lock);
2844 if (data_sinfo->total_bytes - data_sinfo->bytes_used -
2845 data_sinfo->bytes_delalloc - data_sinfo->bytes_reserved -
2846 data_sinfo->bytes_pinned - data_sinfo->bytes_readonly -
2847 data_sinfo->bytes_may_use - data_sinfo->bytes_super < bytes) {
2848 struct btrfs_trans_handle *trans;
2851 * if we don't have enough free bytes in this space then we need
2852 * to alloc a new chunk.
2854 if (!data_sinfo->full) {
2857 data_sinfo->force_alloc = 1;
2858 spin_unlock(&data_sinfo->lock);
2860 alloc_target = btrfs_get_alloc_profile(root, 1);
2861 trans = btrfs_start_transaction(root, 1);
2865 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
2866 bytes + 2 * 1024 * 1024,
2868 btrfs_end_transaction(trans, root);
2873 spin_unlock(&data_sinfo->lock);
2875 /* commit the current transaction and try again */
2878 trans = btrfs_join_transaction(root, 1);
2881 ret = btrfs_commit_transaction(trans, root);
2887 printk(KERN_ERR "no space left, need %llu, %llu delalloc bytes"
2888 ", %llu bytes_used, %llu bytes_reserved, "
2889 "%llu bytes_pinned, %llu bytes_readonly, %llu may use "
2890 "%llu total\n", (unsigned long long)bytes,
2891 (unsigned long long)data_sinfo->bytes_delalloc,
2892 (unsigned long long)data_sinfo->bytes_used,
2893 (unsigned long long)data_sinfo->bytes_reserved,
2894 (unsigned long long)data_sinfo->bytes_pinned,
2895 (unsigned long long)data_sinfo->bytes_readonly,
2896 (unsigned long long)data_sinfo->bytes_may_use,
2897 (unsigned long long)data_sinfo->total_bytes);
2900 data_sinfo->bytes_may_use += bytes;
2901 BTRFS_I(inode)->reserved_bytes += bytes;
2902 spin_unlock(&data_sinfo->lock);
2904 return btrfs_check_metadata_free_space(root);
2908 * if there was an error for whatever reason after calling
2909 * btrfs_check_data_free_space, call this so we can cleanup the counters.
2911 void btrfs_free_reserved_data_space(struct btrfs_root *root,
2912 struct inode *inode, u64 bytes)
2914 struct btrfs_space_info *data_sinfo;
2916 /* make sure bytes are sectorsize aligned */
2917 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
2919 data_sinfo = BTRFS_I(inode)->space_info;
2920 spin_lock(&data_sinfo->lock);
2921 data_sinfo->bytes_may_use -= bytes;
2922 BTRFS_I(inode)->reserved_bytes -= bytes;
2923 spin_unlock(&data_sinfo->lock);
2926 /* called when we are adding a delalloc extent to the inode's io_tree */
2927 void btrfs_delalloc_reserve_space(struct btrfs_root *root, struct inode *inode,
2930 struct btrfs_space_info *data_sinfo;
2932 /* get the space info for where this inode will be storing its data */
2933 data_sinfo = BTRFS_I(inode)->space_info;
2935 /* make sure we have enough space to handle the data first */
2936 spin_lock(&data_sinfo->lock);
2937 data_sinfo->bytes_delalloc += bytes;
2940 * we are adding a delalloc extent without calling
2941 * btrfs_check_data_free_space first. This happens on a weird
2942 * writepage condition, but shouldn't hurt our accounting
2944 if (unlikely(bytes > BTRFS_I(inode)->reserved_bytes)) {
2945 data_sinfo->bytes_may_use -= BTRFS_I(inode)->reserved_bytes;
2946 BTRFS_I(inode)->reserved_bytes = 0;
2948 data_sinfo->bytes_may_use -= bytes;
2949 BTRFS_I(inode)->reserved_bytes -= bytes;
2952 spin_unlock(&data_sinfo->lock);
2955 /* called when we are clearing an delalloc extent from the inode's io_tree */
2956 void btrfs_delalloc_free_space(struct btrfs_root *root, struct inode *inode,
2959 struct btrfs_space_info *info;
2961 info = BTRFS_I(inode)->space_info;
2963 spin_lock(&info->lock);
2964 info->bytes_delalloc -= bytes;
2965 spin_unlock(&info->lock);
2968 static void force_metadata_allocation(struct btrfs_fs_info *info)
2970 struct list_head *head = &info->space_info;
2971 struct btrfs_space_info *found;
2974 list_for_each_entry_rcu(found, head, list) {
2975 if (found->flags & BTRFS_BLOCK_GROUP_METADATA)
2976 found->force_alloc = 1;
2981 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
2982 struct btrfs_root *extent_root, u64 alloc_bytes,
2983 u64 flags, int force)
2985 struct btrfs_space_info *space_info;
2986 struct btrfs_fs_info *fs_info = extent_root->fs_info;
2990 mutex_lock(&fs_info->chunk_mutex);
2992 flags = btrfs_reduce_alloc_profile(extent_root, flags);
2994 space_info = __find_space_info(extent_root->fs_info, flags);
2996 ret = update_space_info(extent_root->fs_info, flags,
3000 BUG_ON(!space_info);
3002 spin_lock(&space_info->lock);
3003 if (space_info->force_alloc) {
3005 space_info->force_alloc = 0;
3007 if (space_info->full) {
3008 spin_unlock(&space_info->lock);
3012 thresh = space_info->total_bytes - space_info->bytes_readonly;
3013 thresh = div_factor(thresh, 6);
3015 (space_info->bytes_used + space_info->bytes_pinned +
3016 space_info->bytes_reserved + alloc_bytes) < thresh) {
3017 spin_unlock(&space_info->lock);
3020 spin_unlock(&space_info->lock);
3023 * if we're doing a data chunk, go ahead and make sure that
3024 * we keep a reasonable number of metadata chunks allocated in the
3027 if (flags & BTRFS_BLOCK_GROUP_DATA) {
3028 fs_info->data_chunk_allocations++;
3029 if (!(fs_info->data_chunk_allocations %
3030 fs_info->metadata_ratio))
3031 force_metadata_allocation(fs_info);
3034 ret = btrfs_alloc_chunk(trans, extent_root, flags);
3036 space_info->full = 1;
3038 mutex_unlock(&extent_root->fs_info->chunk_mutex);
3042 static int update_block_group(struct btrfs_trans_handle *trans,
3043 struct btrfs_root *root,
3044 u64 bytenr, u64 num_bytes, int alloc,
3047 struct btrfs_block_group_cache *cache;
3048 struct btrfs_fs_info *info = root->fs_info;
3049 u64 total = num_bytes;
3053 /* block accounting for super block */
3054 spin_lock(&info->delalloc_lock);
3055 old_val = btrfs_super_bytes_used(&info->super_copy);
3057 old_val += num_bytes;
3059 old_val -= num_bytes;
3060 btrfs_set_super_bytes_used(&info->super_copy, old_val);
3062 /* block accounting for root item */
3063 old_val = btrfs_root_used(&root->root_item);
3065 old_val += num_bytes;
3067 old_val -= num_bytes;
3068 btrfs_set_root_used(&root->root_item, old_val);
3069 spin_unlock(&info->delalloc_lock);
3072 cache = btrfs_lookup_block_group(info, bytenr);
3075 byte_in_group = bytenr - cache->key.objectid;
3076 WARN_ON(byte_in_group > cache->key.offset);
3078 spin_lock(&cache->space_info->lock);
3079 spin_lock(&cache->lock);
3081 old_val = btrfs_block_group_used(&cache->item);
3082 num_bytes = min(total, cache->key.offset - byte_in_group);
3084 old_val += num_bytes;
3085 btrfs_set_block_group_used(&cache->item, old_val);
3086 cache->reserved -= num_bytes;
3087 cache->space_info->bytes_used += num_bytes;
3088 cache->space_info->bytes_reserved -= num_bytes;
3090 cache->space_info->bytes_readonly -= num_bytes;
3091 spin_unlock(&cache->lock);
3092 spin_unlock(&cache->space_info->lock);
3094 old_val -= num_bytes;
3095 cache->space_info->bytes_used -= num_bytes;
3097 cache->space_info->bytes_readonly += num_bytes;
3098 btrfs_set_block_group_used(&cache->item, old_val);
3099 spin_unlock(&cache->lock);
3100 spin_unlock(&cache->space_info->lock);
3104 ret = btrfs_discard_extent(root, bytenr,
3108 ret = btrfs_add_free_space(cache, bytenr,
3113 btrfs_put_block_group(cache);
3115 bytenr += num_bytes;
3120 static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
3122 struct btrfs_block_group_cache *cache;
3125 cache = btrfs_lookup_first_block_group(root->fs_info, search_start);
3129 bytenr = cache->key.objectid;
3130 btrfs_put_block_group(cache);
3136 * this function must be called within transaction
3138 int btrfs_pin_extent(struct btrfs_root *root,
3139 u64 bytenr, u64 num_bytes, int reserved)
3141 struct btrfs_fs_info *fs_info = root->fs_info;
3142 struct btrfs_block_group_cache *cache;
3144 cache = btrfs_lookup_block_group(fs_info, bytenr);
3147 spin_lock(&cache->space_info->lock);
3148 spin_lock(&cache->lock);
3149 cache->pinned += num_bytes;
3150 cache->space_info->bytes_pinned += num_bytes;
3152 cache->reserved -= num_bytes;
3153 cache->space_info->bytes_reserved -= num_bytes;
3155 spin_unlock(&cache->lock);
3156 spin_unlock(&cache->space_info->lock);
3158 btrfs_put_block_group(cache);
3160 set_extent_dirty(fs_info->pinned_extents,
3161 bytenr, bytenr + num_bytes - 1, GFP_NOFS);
3165 static int update_reserved_extents(struct btrfs_block_group_cache *cache,
3166 u64 num_bytes, int reserve)
3168 spin_lock(&cache->space_info->lock);
3169 spin_lock(&cache->lock);
3171 cache->reserved += num_bytes;
3172 cache->space_info->bytes_reserved += num_bytes;
3174 cache->reserved -= num_bytes;
3175 cache->space_info->bytes_reserved -= num_bytes;
3177 spin_unlock(&cache->lock);
3178 spin_unlock(&cache->space_info->lock);
3182 int btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
3183 struct btrfs_root *root)
3185 struct btrfs_fs_info *fs_info = root->fs_info;
3186 struct btrfs_caching_control *next;
3187 struct btrfs_caching_control *caching_ctl;
3188 struct btrfs_block_group_cache *cache;
3190 down_write(&fs_info->extent_commit_sem);
3192 list_for_each_entry_safe(caching_ctl, next,
3193 &fs_info->caching_block_groups, list) {
3194 cache = caching_ctl->block_group;
3195 if (block_group_cache_done(cache)) {
3196 cache->last_byte_to_unpin = (u64)-1;
3197 list_del_init(&caching_ctl->list);
3198 put_caching_control(caching_ctl);
3200 cache->last_byte_to_unpin = caching_ctl->progress;
3204 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
3205 fs_info->pinned_extents = &fs_info->freed_extents[1];
3207 fs_info->pinned_extents = &fs_info->freed_extents[0];
3209 up_write(&fs_info->extent_commit_sem);
3213 static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
3215 struct btrfs_fs_info *fs_info = root->fs_info;
3216 struct btrfs_block_group_cache *cache = NULL;
3219 while (start <= end) {
3221 start >= cache->key.objectid + cache->key.offset) {
3223 btrfs_put_block_group(cache);
3224 cache = btrfs_lookup_block_group(fs_info, start);
3228 len = cache->key.objectid + cache->key.offset - start;
3229 len = min(len, end + 1 - start);
3231 if (start < cache->last_byte_to_unpin) {
3232 len = min(len, cache->last_byte_to_unpin - start);
3233 btrfs_add_free_space(cache, start, len);
3236 spin_lock(&cache->space_info->lock);
3237 spin_lock(&cache->lock);
3238 cache->pinned -= len;
3239 cache->space_info->bytes_pinned -= len;
3240 spin_unlock(&cache->lock);
3241 spin_unlock(&cache->space_info->lock);
3247 btrfs_put_block_group(cache);
3251 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
3252 struct btrfs_root *root)
3254 struct btrfs_fs_info *fs_info = root->fs_info;
3255 struct extent_io_tree *unpin;
3260 if (fs_info->pinned_extents == &fs_info->freed_extents[0])
3261 unpin = &fs_info->freed_extents[1];
3263 unpin = &fs_info->freed_extents[0];
3266 ret = find_first_extent_bit(unpin, 0, &start, &end,
3271 ret = btrfs_discard_extent(root, start, end + 1 - start);
3273 clear_extent_dirty(unpin, start, end, GFP_NOFS);
3274 unpin_extent_range(root, start, end);
3281 static int pin_down_bytes(struct btrfs_trans_handle *trans,
3282 struct btrfs_root *root,
3283 struct btrfs_path *path,
3284 u64 bytenr, u64 num_bytes,
3285 int is_data, int reserved,
3286 struct extent_buffer **must_clean)
3289 struct extent_buffer *buf;
3294 buf = btrfs_find_tree_block(root, bytenr, num_bytes);
3298 /* we can reuse a block if it hasn't been written
3299 * and it is from this transaction. We can't
3300 * reuse anything from the tree log root because
3301 * it has tiny sub-transactions.
3303 if (btrfs_buffer_uptodate(buf, 0) &&
3304 btrfs_try_tree_lock(buf)) {
3305 u64 header_owner = btrfs_header_owner(buf);
3306 u64 header_transid = btrfs_header_generation(buf);
3307 if (header_owner != BTRFS_TREE_LOG_OBJECTID &&
3308 header_transid == trans->transid &&
3309 !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
3313 btrfs_tree_unlock(buf);
3315 free_extent_buffer(buf);
3318 btrfs_set_path_blocking(path);
3319 /* unlocks the pinned mutex */
3320 btrfs_pin_extent(root, bytenr, num_bytes, reserved);
3326 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
3327 struct btrfs_root *root,
3328 u64 bytenr, u64 num_bytes, u64 parent,
3329 u64 root_objectid, u64 owner_objectid,
3330 u64 owner_offset, int refs_to_drop,
3331 struct btrfs_delayed_extent_op *extent_op)
3333 struct btrfs_key key;
3334 struct btrfs_path *path;
3335 struct btrfs_fs_info *info = root->fs_info;
3336 struct btrfs_root *extent_root = info->extent_root;
3337 struct extent_buffer *leaf;
3338 struct btrfs_extent_item *ei;
3339 struct btrfs_extent_inline_ref *iref;
3342 int extent_slot = 0;
3343 int found_extent = 0;
3348 path = btrfs_alloc_path();
3353 path->leave_spinning = 1;
3355 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
3356 BUG_ON(!is_data && refs_to_drop != 1);
3358 ret = lookup_extent_backref(trans, extent_root, path, &iref,
3359 bytenr, num_bytes, parent,
3360 root_objectid, owner_objectid,
3363 extent_slot = path->slots[0];
3364 while (extent_slot >= 0) {
3365 btrfs_item_key_to_cpu(path->nodes[0], &key,
3367 if (key.objectid != bytenr)
3369 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
3370 key.offset == num_bytes) {
3374 if (path->slots[0] - extent_slot > 5)
3378 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
3379 item_size = btrfs_item_size_nr(path->nodes[0], extent_slot);
3380 if (found_extent && item_size < sizeof(*ei))
3383 if (!found_extent) {
3385 ret = remove_extent_backref(trans, extent_root, path,
3389 btrfs_release_path(extent_root, path);
3390 path->leave_spinning = 1;
3392 key.objectid = bytenr;
3393 key.type = BTRFS_EXTENT_ITEM_KEY;
3394 key.offset = num_bytes;
3396 ret = btrfs_search_slot(trans, extent_root,
3399 printk(KERN_ERR "umm, got %d back from search"
3400 ", was looking for %llu\n", ret,
3401 (unsigned long long)bytenr);
3402 btrfs_print_leaf(extent_root, path->nodes[0]);
3405 extent_slot = path->slots[0];
3408 btrfs_print_leaf(extent_root, path->nodes[0]);
3410 printk(KERN_ERR "btrfs unable to find ref byte nr %llu "
3411 "parent %llu root %llu owner %llu offset %llu\n",
3412 (unsigned long long)bytenr,
3413 (unsigned long long)parent,
3414 (unsigned long long)root_objectid,
3415 (unsigned long long)owner_objectid,
3416 (unsigned long long)owner_offset);
3419 leaf = path->nodes[0];
3420 item_size = btrfs_item_size_nr(leaf, extent_slot);
3421 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
3422 if (item_size < sizeof(*ei)) {
3423 BUG_ON(found_extent || extent_slot != path->slots[0]);
3424 ret = convert_extent_item_v0(trans, extent_root, path,
3428 btrfs_release_path(extent_root, path);
3429 path->leave_spinning = 1;
3431 key.objectid = bytenr;
3432 key.type = BTRFS_EXTENT_ITEM_KEY;
3433 key.offset = num_bytes;
3435 ret = btrfs_search_slot(trans, extent_root, &key, path,
3438 printk(KERN_ERR "umm, got %d back from search"
3439 ", was looking for %llu\n", ret,
3440 (unsigned long long)bytenr);
3441 btrfs_print_leaf(extent_root, path->nodes[0]);
3444 extent_slot = path->slots[0];
3445 leaf = path->nodes[0];
3446 item_size = btrfs_item_size_nr(leaf, extent_slot);
3449 BUG_ON(item_size < sizeof(*ei));
3450 ei = btrfs_item_ptr(leaf, extent_slot,
3451 struct btrfs_extent_item);
3452 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID) {
3453 struct btrfs_tree_block_info *bi;
3454 BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
3455 bi = (struct btrfs_tree_block_info *)(ei + 1);
3456 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
3459 refs = btrfs_extent_refs(leaf, ei);
3460 BUG_ON(refs < refs_to_drop);
3461 refs -= refs_to_drop;
3465 __run_delayed_extent_op(extent_op, leaf, ei);
3467 * In the case of inline back ref, reference count will
3468 * be updated by remove_extent_backref
3471 BUG_ON(!found_extent);
3473 btrfs_set_extent_refs(leaf, ei, refs);
3474 btrfs_mark_buffer_dirty(leaf);
3477 ret = remove_extent_backref(trans, extent_root, path,
3484 struct extent_buffer *must_clean = NULL;
3487 BUG_ON(is_data && refs_to_drop !=
3488 extent_data_ref_count(root, path, iref));
3490 BUG_ON(path->slots[0] != extent_slot);
3492 BUG_ON(path->slots[0] != extent_slot + 1);
3493 path->slots[0] = extent_slot;
3498 ret = pin_down_bytes(trans, root, path, bytenr,
3499 num_bytes, is_data, 0, &must_clean);
3504 * it is going to be very rare for someone to be waiting
3505 * on the block we're freeing. del_items might need to
3506 * schedule, so rather than get fancy, just force it
3510 btrfs_set_lock_blocking(must_clean);
3512 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
3515 btrfs_release_path(extent_root, path);
3518 clean_tree_block(NULL, root, must_clean);
3519 btrfs_tree_unlock(must_clean);
3520 free_extent_buffer(must_clean);
3524 ret = btrfs_del_csums(trans, root, bytenr, num_bytes);
3527 invalidate_mapping_pages(info->btree_inode->i_mapping,
3528 bytenr >> PAGE_CACHE_SHIFT,
3529 (bytenr + num_bytes - 1) >> PAGE_CACHE_SHIFT);
3532 ret = update_block_group(trans, root, bytenr, num_bytes, 0,
3536 btrfs_free_path(path);
3541 * when we free an extent, it is possible (and likely) that we free the last
3542 * delayed ref for that extent as well. This searches the delayed ref tree for
3543 * a given extent, and if there are no other delayed refs to be processed, it
3544 * removes it from the tree.
3546 static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans,
3547 struct btrfs_root *root, u64 bytenr)
3549 struct btrfs_delayed_ref_head *head;
3550 struct btrfs_delayed_ref_root *delayed_refs;
3551 struct btrfs_delayed_ref_node *ref;
3552 struct rb_node *node;
3555 delayed_refs = &trans->transaction->delayed_refs;
3556 spin_lock(&delayed_refs->lock);
3557 head = btrfs_find_delayed_ref_head(trans, bytenr);
3561 node = rb_prev(&head->node.rb_node);
3565 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
3567 /* there are still entries for this ref, we can't drop it */
3568 if (ref->bytenr == bytenr)
3571 if (head->extent_op) {
3572 if (!head->must_insert_reserved)
3574 kfree(head->extent_op);
3575 head->extent_op = NULL;
3579 * waiting for the lock here would deadlock. If someone else has it
3580 * locked they are already in the process of dropping it anyway
3582 if (!mutex_trylock(&head->mutex))
3586 * at this point we have a head with no other entries. Go
3587 * ahead and process it.
3589 head->node.in_tree = 0;
3590 rb_erase(&head->node.rb_node, &delayed_refs->root);
3592 delayed_refs->num_entries--;
3595 * we don't take a ref on the node because we're removing it from the
3596 * tree, so we just steal the ref the tree was holding.
3598 delayed_refs->num_heads--;
3599 if (list_empty(&head->cluster))
3600 delayed_refs->num_heads_ready--;
3602 list_del_init(&head->cluster);
3603 spin_unlock(&delayed_refs->lock);
3605 ret = run_one_delayed_ref(trans, root->fs_info->tree_root,
3606 &head->node, head->extent_op,
3607 head->must_insert_reserved);
3609 btrfs_put_delayed_ref(&head->node);
3612 spin_unlock(&delayed_refs->lock);
3616 int btrfs_free_extent(struct btrfs_trans_handle *trans,
3617 struct btrfs_root *root,
3618 u64 bytenr, u64 num_bytes, u64 parent,
3619 u64 root_objectid, u64 owner, u64 offset)
3624 * tree log blocks never actually go into the extent allocation
3625 * tree, just update pinning info and exit early.
3627 if (root_objectid == BTRFS_TREE_LOG_OBJECTID) {
3628 WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID);
3629 /* unlocks the pinned mutex */
3630 btrfs_pin_extent(root, bytenr, num_bytes, 1);
3632 } else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
3633 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
3634 parent, root_objectid, (int)owner,
3635 BTRFS_DROP_DELAYED_REF, NULL);
3637 ret = check_ref_cleanup(trans, root, bytenr);
3640 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
3641 parent, root_objectid, owner,
3642 offset, BTRFS_DROP_DELAYED_REF, NULL);
3648 static u64 stripe_align(struct btrfs_root *root, u64 val)
3650 u64 mask = ((u64)root->stripesize - 1);
3651 u64 ret = (val + mask) & ~mask;
3656 * when we wait for progress in the block group caching, its because
3657 * our allocation attempt failed at least once. So, we must sleep
3658 * and let some progress happen before we try again.
3660 * This function will sleep at least once waiting for new free space to
3661 * show up, and then it will check the block group free space numbers
3662 * for our min num_bytes. Another option is to have it go ahead
3663 * and look in the rbtree for a free extent of a given size, but this
3667 wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
3670 struct btrfs_caching_control *caching_ctl;
3673 caching_ctl = get_caching_control(cache);
3677 wait_event(caching_ctl->wait, block_group_cache_done(cache) ||
3678 (cache->free_space >= num_bytes));
3680 put_caching_control(caching_ctl);
3685 wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
3687 struct btrfs_caching_control *caching_ctl;
3690 caching_ctl = get_caching_control(cache);
3694 wait_event(caching_ctl->wait, block_group_cache_done(cache));
3696 put_caching_control(caching_ctl);
3700 enum btrfs_loop_type {
3701 LOOP_CACHED_ONLY = 0,
3702 LOOP_CACHING_NOWAIT = 1,
3703 LOOP_CACHING_WAIT = 2,
3704 LOOP_ALLOC_CHUNK = 3,
3705 LOOP_NO_EMPTY_SIZE = 4,
3709 * walks the btree of allocated extents and find a hole of a given size.
3710 * The key ins is changed to record the hole:
3711 * ins->objectid == block start
3712 * ins->flags = BTRFS_EXTENT_ITEM_KEY
3713 * ins->offset == number of blocks
3714 * Any available blocks before search_start are skipped.
3716 static noinline int find_free_extent(struct btrfs_trans_handle *trans,
3717 struct btrfs_root *orig_root,
3718 u64 num_bytes, u64 empty_size,
3719 u64 search_start, u64 search_end,
3720 u64 hint_byte, struct btrfs_key *ins,
3721 u64 exclude_start, u64 exclude_nr,
3725 struct btrfs_root *root = orig_root->fs_info->extent_root;
3726 struct btrfs_free_cluster *last_ptr = NULL;
3727 struct btrfs_block_group_cache *block_group = NULL;
3728 int empty_cluster = 2 * 1024 * 1024;
3729 int allowed_chunk_alloc = 0;
3730 struct btrfs_space_info *space_info;
3731 int last_ptr_loop = 0;
3733 bool found_uncached_bg = false;
3734 bool failed_cluster_refill = false;
3736 WARN_ON(num_bytes < root->sectorsize);
3737 btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
3741 space_info = __find_space_info(root->fs_info, data);
3743 if (orig_root->ref_cows || empty_size)
3744 allowed_chunk_alloc = 1;
3746 if (data & BTRFS_BLOCK_GROUP_METADATA) {
3747 last_ptr = &root->fs_info->meta_alloc_cluster;
3748 if (!btrfs_test_opt(root, SSD))
3749 empty_cluster = 64 * 1024;
3752 if ((data & BTRFS_BLOCK_GROUP_DATA) && btrfs_test_opt(root, SSD)) {
3753 last_ptr = &root->fs_info->data_alloc_cluster;
3757 spin_lock(&last_ptr->lock);
3758 if (last_ptr->block_group)
3759 hint_byte = last_ptr->window_start;
3760 spin_unlock(&last_ptr->lock);
3763 search_start = max(search_start, first_logical_byte(root, 0));
3764 search_start = max(search_start, hint_byte);
3769 if (search_start == hint_byte) {
3770 block_group = btrfs_lookup_block_group(root->fs_info,
3773 * we don't want to use the block group if it doesn't match our
3774 * allocation bits, or if its not cached.
3776 if (block_group && block_group_bits(block_group, data) &&
3777 block_group_cache_done(block_group)) {
3778 down_read(&space_info->groups_sem);
3779 if (list_empty(&block_group->list) ||
3782 * someone is removing this block group,
3783 * we can't jump into the have_block_group
3784 * target because our list pointers are not
3787 btrfs_put_block_group(block_group);
3788 up_read(&space_info->groups_sem);
3790 goto have_block_group;
3791 } else if (block_group) {
3792 btrfs_put_block_group(block_group);
3797 down_read(&space_info->groups_sem);
3798 list_for_each_entry(block_group, &space_info->block_groups, list) {
3802 atomic_inc(&block_group->count);
3803 search_start = block_group->key.objectid;
3806 if (unlikely(block_group->cached == BTRFS_CACHE_NO)) {
3808 * we want to start caching kthreads, but not too many
3809 * right off the bat so we don't overwhelm the system,
3810 * so only start them if there are less than 2 and we're
3811 * in the initial allocation phase.
3813 if (loop > LOOP_CACHING_NOWAIT ||
3814 atomic_read(&space_info->caching_threads) < 2) {
3815 ret = cache_block_group(block_group);
3820 cached = block_group_cache_done(block_group);
3821 if (unlikely(!cached)) {
3822 found_uncached_bg = true;
3824 /* if we only want cached bgs, loop */
3825 if (loop == LOOP_CACHED_ONLY)
3829 if (unlikely(block_group->ro))
3833 * Ok we want to try and use the cluster allocator, so lets look
3834 * there, unless we are on LOOP_NO_EMPTY_SIZE, since we will
3835 * have tried the cluster allocator plenty of times at this
3836 * point and not have found anything, so we are likely way too
3837 * fragmented for the clustering stuff to find anything, so lets
3838 * just skip it and let the allocator find whatever block it can
3841 if (last_ptr && loop < LOOP_NO_EMPTY_SIZE) {
3843 * the refill lock keeps out other
3844 * people trying to start a new cluster
3846 spin_lock(&last_ptr->refill_lock);
3847 if (last_ptr->block_group &&
3848 (last_ptr->block_group->ro ||
3849 !block_group_bits(last_ptr->block_group, data))) {
3851 goto refill_cluster;
3854 offset = btrfs_alloc_from_cluster(block_group, last_ptr,
3855 num_bytes, search_start);
3857 /* we have a block, we're done */
3858 spin_unlock(&last_ptr->refill_lock);
3862 spin_lock(&last_ptr->lock);
3864 * whoops, this cluster doesn't actually point to
3865 * this block group. Get a ref on the block
3866 * group is does point to and try again
3868 if (!last_ptr_loop && last_ptr->block_group &&
3869 last_ptr->block_group != block_group) {
3871 btrfs_put_block_group(block_group);
3872 block_group = last_ptr->block_group;
3873 atomic_inc(&block_group->count);
3874 spin_unlock(&last_ptr->lock);
3875 spin_unlock(&last_ptr->refill_lock);
3878 search_start = block_group->key.objectid;
3880 * we know this block group is properly
3881 * in the list because
3882 * btrfs_remove_block_group, drops the
3883 * cluster before it removes the block
3884 * group from the list
3886 goto have_block_group;
3888 spin_unlock(&last_ptr->lock);
3891 * this cluster didn't work out, free it and
3894 btrfs_return_cluster_to_free_space(NULL, last_ptr);
3898 /* allocate a cluster in this block group */
3899 ret = btrfs_find_space_cluster(trans, root,
3900 block_group, last_ptr,
3902 empty_cluster + empty_size);
3905 * now pull our allocation out of this
3908 offset = btrfs_alloc_from_cluster(block_group,
3909 last_ptr, num_bytes,
3912 /* we found one, proceed */
3913 spin_unlock(&last_ptr->refill_lock);
3916 } else if (!cached && loop > LOOP_CACHING_NOWAIT
3917 && !failed_cluster_refill) {
3918 spin_unlock(&last_ptr->refill_lock);
3920 failed_cluster_refill = true;
3921 wait_block_group_cache_progress(block_group,
3922 num_bytes + empty_cluster + empty_size);
3923 goto have_block_group;
3927 * at this point we either didn't find a cluster
3928 * or we weren't able to allocate a block from our
3929 * cluster. Free the cluster we've been trying
3930 * to use, and go to the next block group
3932 btrfs_return_cluster_to_free_space(NULL, last_ptr);
3933 spin_unlock(&last_ptr->refill_lock);
3937 offset = btrfs_find_space_for_alloc(block_group, search_start,
3938 num_bytes, empty_size);
3939 if (!offset && (cached || (!cached &&
3940 loop == LOOP_CACHING_NOWAIT))) {
3942 } else if (!offset && (!cached &&
3943 loop > LOOP_CACHING_NOWAIT)) {
3944 wait_block_group_cache_progress(block_group,
3945 num_bytes + empty_size);
3946 goto have_block_group;
3949 search_start = stripe_align(root, offset);
3950 /* move on to the next group */
3951 if (search_start + num_bytes >= search_end) {
3952 btrfs_add_free_space(block_group, offset, num_bytes);
3956 /* move on to the next group */
3957 if (search_start + num_bytes >
3958 block_group->key.objectid + block_group->key.offset) {
3959 btrfs_add_free_space(block_group, offset, num_bytes);
3963 if (exclude_nr > 0 &&
3964 (search_start + num_bytes > exclude_start &&
3965 search_start < exclude_start + exclude_nr)) {
3966 search_start = exclude_start + exclude_nr;
3968 btrfs_add_free_space(block_group, offset, num_bytes);
3970 * if search_start is still in this block group
3971 * then we just re-search this block group
3973 if (search_start >= block_group->key.objectid &&
3974 search_start < (block_group->key.objectid +
3975 block_group->key.offset))
3976 goto have_block_group;
3980 ins->objectid = search_start;
3981 ins->offset = num_bytes;
3983 if (offset < search_start)
3984 btrfs_add_free_space(block_group, offset,
3985 search_start - offset);
3986 BUG_ON(offset > search_start);
3988 update_reserved_extents(block_group, num_bytes, 1);
3990 /* we are all good, lets return */
3993 failed_cluster_refill = false;
3994 btrfs_put_block_group(block_group);
3996 up_read(&space_info->groups_sem);
3998 /* LOOP_CACHED_ONLY, only search fully cached block groups
3999 * LOOP_CACHING_NOWAIT, search partially cached block groups, but
4000 * dont wait foR them to finish caching
4001 * LOOP_CACHING_WAIT, search everything, and wait if our bg is caching
4002 * LOOP_ALLOC_CHUNK, force a chunk allocation and try again
4003 * LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try
4006 if (!ins->objectid && loop < LOOP_NO_EMPTY_SIZE &&
4007 (found_uncached_bg || empty_size || empty_cluster ||
4008 allowed_chunk_alloc)) {
4009 if (found_uncached_bg) {
4010 found_uncached_bg = false;
4011 if (loop < LOOP_CACHING_WAIT) {
4017 if (loop == LOOP_ALLOC_CHUNK) {
4022 if (allowed_chunk_alloc) {
4023 ret = do_chunk_alloc(trans, root, num_bytes +
4024 2 * 1024 * 1024, data, 1);
4025 allowed_chunk_alloc = 0;
4027 space_info->force_alloc = 1;
4030 if (loop < LOOP_NO_EMPTY_SIZE) {
4035 } else if (!ins->objectid) {
4039 /* we found what we needed */
4040 if (ins->objectid) {
4041 if (!(data & BTRFS_BLOCK_GROUP_DATA))
4042 trans->block_group = block_group->key.objectid;
4044 btrfs_put_block_group(block_group);
4051 static void dump_space_info(struct btrfs_space_info *info, u64 bytes)
4053 struct btrfs_block_group_cache *cache;
4055 printk(KERN_INFO "space_info has %llu free, is %sfull\n",
4056 (unsigned long long)(info->total_bytes - info->bytes_used -
4057 info->bytes_pinned - info->bytes_reserved),
4058 (info->full) ? "" : "not ");
4059 printk(KERN_INFO "space_info total=%llu, pinned=%llu, delalloc=%llu,"
4060 " may_use=%llu, used=%llu\n",
4061 (unsigned long long)info->total_bytes,
4062 (unsigned long long)info->bytes_pinned,
4063 (unsigned long long)info->bytes_delalloc,
4064 (unsigned long long)info->bytes_may_use,
4065 (unsigned long long)info->bytes_used);
4067 down_read(&info->groups_sem);
4068 list_for_each_entry(cache, &info->block_groups, list) {
4069 spin_lock(&cache->lock);
4070 printk(KERN_INFO "block group %llu has %llu bytes, %llu used "
4071 "%llu pinned %llu reserved\n",
4072 (unsigned long long)cache->key.objectid,
4073 (unsigned long long)cache->key.offset,
4074 (unsigned long long)btrfs_block_group_used(&cache->item),
4075 (unsigned long long)cache->pinned,
4076 (unsigned long long)cache->reserved);
4077 btrfs_dump_free_space(cache, bytes);
4078 spin_unlock(&cache->lock);
4080 up_read(&info->groups_sem);
4083 int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
4084 struct btrfs_root *root,
4085 u64 num_bytes, u64 min_alloc_size,
4086 u64 empty_size, u64 hint_byte,
4087 u64 search_end, struct btrfs_key *ins,
4091 u64 search_start = 0;
4092 struct btrfs_fs_info *info = root->fs_info;
4094 data = btrfs_get_alloc_profile(root, data);
4097 * the only place that sets empty_size is btrfs_realloc_node, which
4098 * is not called recursively on allocations
4100 if (empty_size || root->ref_cows) {
4101 if (!(data & BTRFS_BLOCK_GROUP_METADATA)) {
4102 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
4104 BTRFS_BLOCK_GROUP_METADATA |
4105 (info->metadata_alloc_profile &
4106 info->avail_metadata_alloc_bits), 0);
4108 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
4109 num_bytes + 2 * 1024 * 1024, data, 0);
4112 WARN_ON(num_bytes < root->sectorsize);
4113 ret = find_free_extent(trans, root, num_bytes, empty_size,
4114 search_start, search_end, hint_byte, ins,
4115 trans->alloc_exclude_start,
4116 trans->alloc_exclude_nr, data);
4118 if (ret == -ENOSPC && num_bytes > min_alloc_size) {
4119 num_bytes = num_bytes >> 1;
4120 num_bytes = num_bytes & ~(root->sectorsize - 1);
4121 num_bytes = max(num_bytes, min_alloc_size);
4122 do_chunk_alloc(trans, root->fs_info->extent_root,
4123 num_bytes, data, 1);
4126 if (ret == -ENOSPC) {
4127 struct btrfs_space_info *sinfo;
4129 sinfo = __find_space_info(root->fs_info, data);
4130 printk(KERN_ERR "btrfs allocation failed flags %llu, "
4131 "wanted %llu\n", (unsigned long long)data,
4132 (unsigned long long)num_bytes);
4133 dump_space_info(sinfo, num_bytes);
4139 int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len)
4141 struct btrfs_block_group_cache *cache;
4144 cache = btrfs_lookup_block_group(root->fs_info, start);
4146 printk(KERN_ERR "Unable to find block group for %llu\n",
4147 (unsigned long long)start);
4151 ret = btrfs_discard_extent(root, start, len);
4153 btrfs_add_free_space(cache, start, len);
4154 update_reserved_extents(cache, len, 0);
4155 btrfs_put_block_group(cache);
4160 static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
4161 struct btrfs_root *root,
4162 u64 parent, u64 root_objectid,
4163 u64 flags, u64 owner, u64 offset,
4164 struct btrfs_key *ins, int ref_mod)
4167 struct btrfs_fs_info *fs_info = root->fs_info;
4168 struct btrfs_extent_item *extent_item;
4169 struct btrfs_extent_inline_ref *iref;
4170 struct btrfs_path *path;
4171 struct extent_buffer *leaf;
4176 type = BTRFS_SHARED_DATA_REF_KEY;
4178 type = BTRFS_EXTENT_DATA_REF_KEY;
4180 size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type);
4182 path = btrfs_alloc_path();
4185 path->leave_spinning = 1;
4186 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
4190 leaf = path->nodes[0];
4191 extent_item = btrfs_item_ptr(leaf, path->slots[0],
4192 struct btrfs_extent_item);
4193 btrfs_set_extent_refs(leaf, extent_item, ref_mod);
4194 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
4195 btrfs_set_extent_flags(leaf, extent_item,
4196 flags | BTRFS_EXTENT_FLAG_DATA);
4198 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
4199 btrfs_set_extent_inline_ref_type(leaf, iref, type);
4201 struct btrfs_shared_data_ref *ref;
4202 ref = (struct btrfs_shared_data_ref *)(iref + 1);
4203 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
4204 btrfs_set_shared_data_ref_count(leaf, ref, ref_mod);
4206 struct btrfs_extent_data_ref *ref;
4207 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
4208 btrfs_set_extent_data_ref_root(leaf, ref, root_objectid);
4209 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
4210 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
4211 btrfs_set_extent_data_ref_count(leaf, ref, ref_mod);
4214 btrfs_mark_buffer_dirty(path->nodes[0]);
4215 btrfs_free_path(path);
4217 ret = update_block_group(trans, root, ins->objectid, ins->offset,
4220 printk(KERN_ERR "btrfs update block group failed for %llu "
4221 "%llu\n", (unsigned long long)ins->objectid,
4222 (unsigned long long)ins->offset);
4228 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
4229 struct btrfs_root *root,
4230 u64 parent, u64 root_objectid,
4231 u64 flags, struct btrfs_disk_key *key,
4232 int level, struct btrfs_key *ins)
4235 struct btrfs_fs_info *fs_info = root->fs_info;
4236 struct btrfs_extent_item *extent_item;
4237 struct btrfs_tree_block_info *block_info;
4238 struct btrfs_extent_inline_ref *iref;
4239 struct btrfs_path *path;
4240 struct extent_buffer *leaf;
4241 u32 size = sizeof(*extent_item) + sizeof(*block_info) + sizeof(*iref);
4243 path = btrfs_alloc_path();
4246 path->leave_spinning = 1;
4247 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
4251 leaf = path->nodes[0];
4252 extent_item = btrfs_item_ptr(leaf, path->slots[0],
4253 struct btrfs_extent_item);
4254 btrfs_set_extent_refs(leaf, extent_item, 1);
4255 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
4256 btrfs_set_extent_flags(leaf, extent_item,
4257 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
4258 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
4260 btrfs_set_tree_block_key(leaf, block_info, key);
4261 btrfs_set_tree_block_level(leaf, block_info, level);
4263 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
4265 BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF));
4266 btrfs_set_extent_inline_ref_type(leaf, iref,
4267 BTRFS_SHARED_BLOCK_REF_KEY);
4268 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
4270 btrfs_set_extent_inline_ref_type(leaf, iref,
4271 BTRFS_TREE_BLOCK_REF_KEY);
4272 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
4275 btrfs_mark_buffer_dirty(leaf);
4276 btrfs_free_path(path);
4278 ret = update_block_group(trans, root, ins->objectid, ins->offset,
4281 printk(KERN_ERR "btrfs update block group failed for %llu "
4282 "%llu\n", (unsigned long long)ins->objectid,
4283 (unsigned long long)ins->offset);
4289 int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
4290 struct btrfs_root *root,
4291 u64 root_objectid, u64 owner,
4292 u64 offset, struct btrfs_key *ins)
4296 BUG_ON(root_objectid == BTRFS_TREE_LOG_OBJECTID);
4298 ret = btrfs_add_delayed_data_ref(trans, ins->objectid, ins->offset,
4299 0, root_objectid, owner, offset,
4300 BTRFS_ADD_DELAYED_EXTENT, NULL);
4305 * this is used by the tree logging recovery code. It records that
4306 * an extent has been allocated and makes sure to clear the free
4307 * space cache bits as well
4309 int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
4310 struct btrfs_root *root,
4311 u64 root_objectid, u64 owner, u64 offset,
4312 struct btrfs_key *ins)
4315 struct btrfs_block_group_cache *block_group;
4316 struct btrfs_caching_control *caching_ctl;
4317 u64 start = ins->objectid;
4318 u64 num_bytes = ins->offset;
4320 block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
4321 cache_block_group(block_group);
4322 caching_ctl = get_caching_control(block_group);
4325 BUG_ON(!block_group_cache_done(block_group));
4326 ret = btrfs_remove_free_space(block_group, start, num_bytes);
4329 mutex_lock(&caching_ctl->mutex);
4331 if (start >= caching_ctl->progress) {
4332 ret = add_excluded_extent(root, start, num_bytes);
4334 } else if (start + num_bytes <= caching_ctl->progress) {
4335 ret = btrfs_remove_free_space(block_group,
4339 num_bytes = caching_ctl->progress - start;
4340 ret = btrfs_remove_free_space(block_group,
4344 start = caching_ctl->progress;
4345 num_bytes = ins->objectid + ins->offset -
4346 caching_ctl->progress;
4347 ret = add_excluded_extent(root, start, num_bytes);
4351 mutex_unlock(&caching_ctl->mutex);
4352 put_caching_control(caching_ctl);
4355 update_reserved_extents(block_group, ins->offset, 1);
4356 btrfs_put_block_group(block_group);
4357 ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,
4358 0, owner, offset, ins, 1);
4363 * finds a free extent and does all the dirty work required for allocation
4364 * returns the key for the extent through ins, and a tree buffer for
4365 * the first block of the extent through buf.
4367 * returns 0 if everything worked, non-zero otherwise.
4369 static int alloc_tree_block(struct btrfs_trans_handle *trans,
4370 struct btrfs_root *root,
4371 u64 num_bytes, u64 parent, u64 root_objectid,
4372 struct btrfs_disk_key *key, int level,
4373 u64 empty_size, u64 hint_byte, u64 search_end,
4374 struct btrfs_key *ins)
4379 ret = btrfs_reserve_extent(trans, root, num_bytes, num_bytes,
4380 empty_size, hint_byte, search_end,
4385 if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
4387 parent = ins->objectid;
4388 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
4392 if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
4393 struct btrfs_delayed_extent_op *extent_op;
4394 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
4397 memcpy(&extent_op->key, key, sizeof(extent_op->key));
4399 memset(&extent_op->key, 0, sizeof(extent_op->key));
4400 extent_op->flags_to_set = flags;
4401 extent_op->update_key = 1;
4402 extent_op->update_flags = 1;
4403 extent_op->is_data = 0;
4405 ret = btrfs_add_delayed_tree_ref(trans, ins->objectid,
4406 ins->offset, parent, root_objectid,
4407 level, BTRFS_ADD_DELAYED_EXTENT,
4414 struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
4415 struct btrfs_root *root,
4416 u64 bytenr, u32 blocksize,
4419 struct extent_buffer *buf;
4421 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
4423 return ERR_PTR(-ENOMEM);
4424 btrfs_set_header_generation(buf, trans->transid);
4425 btrfs_set_buffer_lockdep_class(buf, level);
4426 btrfs_tree_lock(buf);
4427 clean_tree_block(trans, root, buf);
4429 btrfs_set_lock_blocking(buf);
4430 btrfs_set_buffer_uptodate(buf);
4432 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
4433 set_extent_dirty(&root->dirty_log_pages, buf->start,
4434 buf->start + buf->len - 1, GFP_NOFS);
4436 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
4437 buf->start + buf->len - 1, GFP_NOFS);
4439 trans->blocks_used++;
4440 /* this returns a buffer locked for blocking */
4445 * helper function to allocate a block for a given tree
4446 * returns the tree buffer or NULL.
4448 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
4449 struct btrfs_root *root, u32 blocksize,
4450 u64 parent, u64 root_objectid,
4451 struct btrfs_disk_key *key, int level,
4452 u64 hint, u64 empty_size)
4454 struct btrfs_key ins;
4456 struct extent_buffer *buf;
4458 ret = alloc_tree_block(trans, root, blocksize, parent, root_objectid,
4459 key, level, empty_size, hint, (u64)-1, &ins);
4462 return ERR_PTR(ret);
4465 buf = btrfs_init_new_buffer(trans, root, ins.objectid,
4470 struct walk_control {
4471 u64 refs[BTRFS_MAX_LEVEL];
4472 u64 flags[BTRFS_MAX_LEVEL];
4473 struct btrfs_key update_progress;
4483 #define DROP_REFERENCE 1
4484 #define UPDATE_BACKREF 2
4486 static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
4487 struct btrfs_root *root,
4488 struct walk_control *wc,
4489 struct btrfs_path *path)
4497 struct btrfs_key key;
4498 struct extent_buffer *eb;
4503 if (path->slots[wc->level] < wc->reada_slot) {
4504 wc->reada_count = wc->reada_count * 2 / 3;
4505 wc->reada_count = max(wc->reada_count, 2);
4507 wc->reada_count = wc->reada_count * 3 / 2;
4508 wc->reada_count = min_t(int, wc->reada_count,
4509 BTRFS_NODEPTRS_PER_BLOCK(root));
4512 eb = path->nodes[wc->level];
4513 nritems = btrfs_header_nritems(eb);
4514 blocksize = btrfs_level_size(root, wc->level - 1);
4516 for (slot = path->slots[wc->level]; slot < nritems; slot++) {
4517 if (nread >= wc->reada_count)
4521 bytenr = btrfs_node_blockptr(eb, slot);
4522 generation = btrfs_node_ptr_generation(eb, slot);
4524 if (slot == path->slots[wc->level])
4527 if (wc->stage == UPDATE_BACKREF &&
4528 generation <= root->root_key.offset)
4531 if (wc->stage == DROP_REFERENCE) {
4532 ret = btrfs_lookup_extent_info(trans, root,
4540 if (!wc->update_ref ||
4541 generation <= root->root_key.offset)
4543 btrfs_node_key_to_cpu(eb, &key, slot);
4544 ret = btrfs_comp_cpu_keys(&key,
4545 &wc->update_progress);
4550 ret = readahead_tree_block(root, bytenr, blocksize,
4554 last = bytenr + blocksize;
4557 wc->reada_slot = slot;
4561 * hepler to process tree block while walking down the tree.
4563 * when wc->stage == UPDATE_BACKREF, this function updates
4564 * back refs for pointers in the block.
4566 * NOTE: return value 1 means we should stop walking down.
4568 static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
4569 struct btrfs_root *root,
4570 struct btrfs_path *path,
4571 struct walk_control *wc)
4573 int level = wc->level;
4574 struct extent_buffer *eb = path->nodes[level];
4575 u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF;
4578 if (wc->stage == UPDATE_BACKREF &&
4579 btrfs_header_owner(eb) != root->root_key.objectid)
4583 * when reference count of tree block is 1, it won't increase
4584 * again. once full backref flag is set, we never clear it.
4586 if ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
4587 (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag))) {
4588 BUG_ON(!path->locks[level]);
4589 ret = btrfs_lookup_extent_info(trans, root,
4594 BUG_ON(wc->refs[level] == 0);
4597 if (wc->stage == DROP_REFERENCE) {
4598 if (wc->refs[level] > 1)
4601 if (path->locks[level] && !wc->keep_locks) {
4602 btrfs_tree_unlock(eb);
4603 path->locks[level] = 0;
4608 /* wc->stage == UPDATE_BACKREF */
4609 if (!(wc->flags[level] & flag)) {
4610 BUG_ON(!path->locks[level]);
4611 ret = btrfs_inc_ref(trans, root, eb, 1);
4613 ret = btrfs_dec_ref(trans, root, eb, 0);
4615 ret = btrfs_set_disk_extent_flags(trans, root, eb->start,
4618 wc->flags[level] |= flag;
4622 * the block is shared by multiple trees, so it's not good to
4623 * keep the tree lock
4625 if (path->locks[level] && level > 0) {
4626 btrfs_tree_unlock(eb);
4627 path->locks[level] = 0;
4633 * hepler to process tree block pointer.
4635 * when wc->stage == DROP_REFERENCE, this function checks
4636 * reference count of the block pointed to. if the block
4637 * is shared and we need update back refs for the subtree
4638 * rooted at the block, this function changes wc->stage to
4639 * UPDATE_BACKREF. if the block is shared and there is no
4640 * need to update back, this function drops the reference
4643 * NOTE: return value 1 means we should stop walking down.
4645 static noinline int do_walk_down(struct btrfs_trans_handle *trans,
4646 struct btrfs_root *root,
4647 struct btrfs_path *path,
4648 struct walk_control *wc)
4654 struct btrfs_key key;
4655 struct extent_buffer *next;
4656 int level = wc->level;
4660 generation = btrfs_node_ptr_generation(path->nodes[level],
4661 path->slots[level]);
4663 * if the lower level block was created before the snapshot
4664 * was created, we know there is no need to update back refs
4667 if (wc->stage == UPDATE_BACKREF &&
4668 generation <= root->root_key.offset)
4671 bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]);
4672 blocksize = btrfs_level_size(root, level - 1);
4674 next = btrfs_find_tree_block(root, bytenr, blocksize);
4676 next = btrfs_find_create_tree_block(root, bytenr, blocksize);
4679 btrfs_tree_lock(next);
4680 btrfs_set_lock_blocking(next);
4682 if (wc->stage == DROP_REFERENCE) {
4683 ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
4684 &wc->refs[level - 1],
4685 &wc->flags[level - 1]);
4687 BUG_ON(wc->refs[level - 1] == 0);
4689 if (wc->refs[level - 1] > 1) {
4690 if (!wc->update_ref ||
4691 generation <= root->root_key.offset)
4694 btrfs_node_key_to_cpu(path->nodes[level], &key,
4695 path->slots[level]);
4696 ret = btrfs_comp_cpu_keys(&key, &wc->update_progress);
4700 wc->stage = UPDATE_BACKREF;
4701 wc->shared_level = level - 1;
4705 if (!btrfs_buffer_uptodate(next, generation)) {
4706 btrfs_tree_unlock(next);
4707 free_extent_buffer(next);
4712 if (reada && level == 1)
4713 reada_walk_down(trans, root, wc, path);
4714 next = read_tree_block(root, bytenr, blocksize, generation);
4715 btrfs_tree_lock(next);
4716 btrfs_set_lock_blocking(next);
4720 BUG_ON(level != btrfs_header_level(next));
4721 path->nodes[level] = next;
4722 path->slots[level] = 0;
4723 path->locks[level] = 1;
4729 wc->refs[level - 1] = 0;
4730 wc->flags[level - 1] = 0;
4732 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
4733 parent = path->nodes[level]->start;
4735 BUG_ON(root->root_key.objectid !=
4736 btrfs_header_owner(path->nodes[level]));
4740 ret = btrfs_free_extent(trans, root, bytenr, blocksize, parent,
4741 root->root_key.objectid, level - 1, 0);
4744 btrfs_tree_unlock(next);
4745 free_extent_buffer(next);
4750 * hepler to process tree block while walking up the tree.
4752 * when wc->stage == DROP_REFERENCE, this function drops
4753 * reference count on the block.
4755 * when wc->stage == UPDATE_BACKREF, this function changes
4756 * wc->stage back to DROP_REFERENCE if we changed wc->stage
4757 * to UPDATE_BACKREF previously while processing the block.
4759 * NOTE: return value 1 means we should stop walking up.
4761 static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
4762 struct btrfs_root *root,
4763 struct btrfs_path *path,
4764 struct walk_control *wc)
4767 int level = wc->level;
4768 struct extent_buffer *eb = path->nodes[level];
4771 if (wc->stage == UPDATE_BACKREF) {
4772 BUG_ON(wc->shared_level < level);
4773 if (level < wc->shared_level)
4776 ret = find_next_key(path, level + 1, &wc->update_progress);
4780 wc->stage = DROP_REFERENCE;
4781 wc->shared_level = -1;
4782 path->slots[level] = 0;
4785 * check reference count again if the block isn't locked.
4786 * we should start walking down the tree again if reference
4789 if (!path->locks[level]) {
4791 btrfs_tree_lock(eb);
4792 btrfs_set_lock_blocking(eb);
4793 path->locks[level] = 1;
4795 ret = btrfs_lookup_extent_info(trans, root,
4800 BUG_ON(wc->refs[level] == 0);
4801 if (wc->refs[level] == 1) {
4802 btrfs_tree_unlock(eb);
4803 path->locks[level] = 0;
4809 /* wc->stage == DROP_REFERENCE */
4810 BUG_ON(wc->refs[level] > 1 && !path->locks[level]);
4812 if (wc->refs[level] == 1) {
4814 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
4815 ret = btrfs_dec_ref(trans, root, eb, 1);
4817 ret = btrfs_dec_ref(trans, root, eb, 0);
4820 /* make block locked assertion in clean_tree_block happy */
4821 if (!path->locks[level] &&
4822 btrfs_header_generation(eb) == trans->transid) {
4823 btrfs_tree_lock(eb);
4824 btrfs_set_lock_blocking(eb);
4825 path->locks[level] = 1;
4827 clean_tree_block(trans, root, eb);
4830 if (eb == root->node) {
4831 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
4834 BUG_ON(root->root_key.objectid !=
4835 btrfs_header_owner(eb));
4837 if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
4838 parent = path->nodes[level + 1]->start;
4840 BUG_ON(root->root_key.objectid !=
4841 btrfs_header_owner(path->nodes[level + 1]));
4844 ret = btrfs_free_extent(trans, root, eb->start, eb->len, parent,
4845 root->root_key.objectid, level, 0);
4848 wc->refs[level] = 0;
4849 wc->flags[level] = 0;
4853 static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
4854 struct btrfs_root *root,
4855 struct btrfs_path *path,
4856 struct walk_control *wc)
4858 int level = wc->level;
4861 while (level >= 0) {
4862 if (path->slots[level] >=
4863 btrfs_header_nritems(path->nodes[level]))
4866 ret = walk_down_proc(trans, root, path, wc);
4873 ret = do_walk_down(trans, root, path, wc);
4875 path->slots[level]++;
4883 static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
4884 struct btrfs_root *root,
4885 struct btrfs_path *path,
4886 struct walk_control *wc, int max_level)
4888 int level = wc->level;
4891 path->slots[level] = btrfs_header_nritems(path->nodes[level]);
4892 while (level < max_level && path->nodes[level]) {
4894 if (path->slots[level] + 1 <
4895 btrfs_header_nritems(path->nodes[level])) {
4896 path->slots[level]++;
4899 ret = walk_up_proc(trans, root, path, wc);
4903 if (path->locks[level]) {
4904 btrfs_tree_unlock(path->nodes[level]);
4905 path->locks[level] = 0;
4907 free_extent_buffer(path->nodes[level]);
4908 path->nodes[level] = NULL;
4916 * drop a subvolume tree.
4918 * this function traverses the tree freeing any blocks that only
4919 * referenced by the tree.
4921 * when a shared tree block is found. this function decreases its
4922 * reference count by one. if update_ref is true, this function
4923 * also make sure backrefs for the shared block and all lower level
4924 * blocks are properly updated.
4926 int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref)
4928 struct btrfs_path *path;
4929 struct btrfs_trans_handle *trans;
4930 struct btrfs_root *tree_root = root->fs_info->tree_root;
4931 struct btrfs_root_item *root_item = &root->root_item;
4932 struct walk_control *wc;
4933 struct btrfs_key key;
4938 path = btrfs_alloc_path();
4941 wc = kzalloc(sizeof(*wc), GFP_NOFS);
4944 trans = btrfs_start_transaction(tree_root, 1);
4946 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
4947 level = btrfs_header_level(root->node);
4948 path->nodes[level] = btrfs_lock_root_node(root);
4949 btrfs_set_lock_blocking(path->nodes[level]);
4950 path->slots[level] = 0;
4951 path->locks[level] = 1;
4952 memset(&wc->update_progress, 0,
4953 sizeof(wc->update_progress));
4955 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
4956 memcpy(&wc->update_progress, &key,
4957 sizeof(wc->update_progress));
4959 level = root_item->drop_level;
4961 path->lowest_level = level;
4962 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4963 path->lowest_level = 0;
4971 * unlock our path, this is safe because only this
4972 * function is allowed to delete this snapshot
4974 btrfs_unlock_up_safe(path, 0);
4976 level = btrfs_header_level(root->node);
4978 btrfs_tree_lock(path->nodes[level]);
4979 btrfs_set_lock_blocking(path->nodes[level]);
4981 ret = btrfs_lookup_extent_info(trans, root,
4982 path->nodes[level]->start,
4983 path->nodes[level]->len,
4987 BUG_ON(wc->refs[level] == 0);
4989 if (level == root_item->drop_level)
4992 btrfs_tree_unlock(path->nodes[level]);
4993 WARN_ON(wc->refs[level] != 1);
4999 wc->shared_level = -1;
5000 wc->stage = DROP_REFERENCE;
5001 wc->update_ref = update_ref;
5003 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
5006 ret = walk_down_tree(trans, root, path, wc);
5012 ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL);
5019 BUG_ON(wc->stage != DROP_REFERENCE);
5023 if (wc->stage == DROP_REFERENCE) {
5025 btrfs_node_key(path->nodes[level],
5026 &root_item->drop_progress,
5027 path->slots[level]);
5028 root_item->drop_level = level;
5031 BUG_ON(wc->level == 0);
5032 if (trans->transaction->in_commit ||
5033 trans->transaction->delayed_refs.flushing) {
5034 ret = btrfs_update_root(trans, tree_root,
5039 btrfs_end_transaction(trans, tree_root);
5040 trans = btrfs_start_transaction(tree_root, 1);
5042 unsigned long update;
5043 update = trans->delayed_ref_updates;
5044 trans->delayed_ref_updates = 0;
5046 btrfs_run_delayed_refs(trans, tree_root,
5050 btrfs_release_path(root, path);
5053 ret = btrfs_del_root(trans, tree_root, &root->root_key);
5056 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
5057 ret = btrfs_find_last_root(tree_root, root->root_key.objectid,
5061 ret = btrfs_del_orphan_item(trans, tree_root,
5062 root->root_key.objectid);
5067 if (root->in_radix) {
5068 btrfs_free_fs_root(tree_root->fs_info, root);
5070 free_extent_buffer(root->node);
5071 free_extent_buffer(root->commit_root);
5075 btrfs_end_transaction(trans, tree_root);
5077 btrfs_free_path(path);
5082 * drop subtree rooted at tree block 'node'.
5084 * NOTE: this function will unlock and release tree block 'node'
5086 int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
5087 struct btrfs_root *root,
5088 struct extent_buffer *node,
5089 struct extent_buffer *parent)
5091 struct btrfs_path *path;
5092 struct walk_control *wc;
5098 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
5100 path = btrfs_alloc_path();
5103 wc = kzalloc(sizeof(*wc), GFP_NOFS);
5106 btrfs_assert_tree_locked(parent);
5107 parent_level = btrfs_header_level(parent);
5108 extent_buffer_get(parent);
5109 path->nodes[parent_level] = parent;
5110 path->slots[parent_level] = btrfs_header_nritems(parent);
5112 btrfs_assert_tree_locked(node);
5113 level = btrfs_header_level(node);
5114 path->nodes[level] = node;
5115 path->slots[level] = 0;
5116 path->locks[level] = 1;
5118 wc->refs[parent_level] = 1;
5119 wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF;
5121 wc->shared_level = -1;
5122 wc->stage = DROP_REFERENCE;
5125 wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
5128 wret = walk_down_tree(trans, root, path, wc);
5134 wret = walk_up_tree(trans, root, path, wc, parent_level);
5142 btrfs_free_path(path);
5147 static unsigned long calc_ra(unsigned long start, unsigned long last,
5150 return min(last, start + nr - 1);
5153 static noinline int relocate_inode_pages(struct inode *inode, u64 start,
5158 unsigned long first_index;
5159 unsigned long last_index;
5162 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
5163 struct file_ra_state *ra;
5164 struct btrfs_ordered_extent *ordered;
5165 unsigned int total_read = 0;
5166 unsigned int total_dirty = 0;
5169 ra = kzalloc(sizeof(*ra), GFP_NOFS);
5171 mutex_lock(&inode->i_mutex);
5172 first_index = start >> PAGE_CACHE_SHIFT;
5173 last_index = (start + len - 1) >> PAGE_CACHE_SHIFT;
5175 /* make sure the dirty trick played by the caller work */
5176 ret = invalidate_inode_pages2_range(inode->i_mapping,
5177 first_index, last_index);
5181 file_ra_state_init(ra, inode->i_mapping);
5183 for (i = first_index ; i <= last_index; i++) {
5184 if (total_read % ra->ra_pages == 0) {
5185 btrfs_force_ra(inode->i_mapping, ra, NULL, i,
5186 calc_ra(i, last_index, ra->ra_pages));
5190 if (((u64)i << PAGE_CACHE_SHIFT) > i_size_read(inode))
5192 page = grab_cache_page(inode->i_mapping, i);
5197 if (!PageUptodate(page)) {
5198 btrfs_readpage(NULL, page);
5200 if (!PageUptodate(page)) {
5202 page_cache_release(page);
5207 wait_on_page_writeback(page);
5209 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
5210 page_end = page_start + PAGE_CACHE_SIZE - 1;
5211 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
5213 ordered = btrfs_lookup_ordered_extent(inode, page_start);
5215 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
5217 page_cache_release(page);
5218 btrfs_start_ordered_extent(inode, ordered, 1);
5219 btrfs_put_ordered_extent(ordered);
5222 set_page_extent_mapped(page);
5224 if (i == first_index)
5225 set_extent_bits(io_tree, page_start, page_end,
5226 EXTENT_BOUNDARY, GFP_NOFS);
5227 btrfs_set_extent_delalloc(inode, page_start, page_end);
5229 set_page_dirty(page);
5232 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
5234 page_cache_release(page);
5239 mutex_unlock(&inode->i_mutex);
5240 balance_dirty_pages_ratelimited_nr(inode->i_mapping, total_dirty);
5244 static noinline int relocate_data_extent(struct inode *reloc_inode,
5245 struct btrfs_key *extent_key,
5248 struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
5249 struct extent_map_tree *em_tree = &BTRFS_I(reloc_inode)->extent_tree;
5250 struct extent_map *em;
5251 u64 start = extent_key->objectid - offset;
5252 u64 end = start + extent_key->offset - 1;
5254 em = alloc_extent_map(GFP_NOFS);
5255 BUG_ON(!em || IS_ERR(em));
5258 em->len = extent_key->offset;
5259 em->block_len = extent_key->offset;
5260 em->block_start = extent_key->objectid;
5261 em->bdev = root->fs_info->fs_devices->latest_bdev;
5262 set_bit(EXTENT_FLAG_PINNED, &em->flags);
5264 /* setup extent map to cheat btrfs_readpage */
5265 lock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
5268 write_lock(&em_tree->lock);
5269 ret = add_extent_mapping(em_tree, em);
5270 write_unlock(&em_tree->lock);
5271 if (ret != -EEXIST) {
5272 free_extent_map(em);
5275 btrfs_drop_extent_cache(reloc_inode, start, end, 0);
5277 unlock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
5279 return relocate_inode_pages(reloc_inode, start, extent_key->offset);
5282 struct btrfs_ref_path {
5284 u64 nodes[BTRFS_MAX_LEVEL];
5286 u64 root_generation;
5293 struct btrfs_key node_keys[BTRFS_MAX_LEVEL];
5294 u64 new_nodes[BTRFS_MAX_LEVEL];
5297 struct disk_extent {
5308 static int is_cowonly_root(u64 root_objectid)
5310 if (root_objectid == BTRFS_ROOT_TREE_OBJECTID ||
5311 root_objectid == BTRFS_EXTENT_TREE_OBJECTID ||
5312 root_objectid == BTRFS_CHUNK_TREE_OBJECTID ||
5313 root_objectid == BTRFS_DEV_TREE_OBJECTID ||
5314 root_objectid == BTRFS_TREE_LOG_OBJECTID ||
5315 root_objectid == BTRFS_CSUM_TREE_OBJECTID)
5320 static noinline int __next_ref_path(struct btrfs_trans_handle *trans,
5321 struct btrfs_root *extent_root,
5322 struct btrfs_ref_path *ref_path,
5325 struct extent_buffer *leaf;
5326 struct btrfs_path *path;
5327 struct btrfs_extent_ref *ref;
5328 struct btrfs_key key;
5329 struct btrfs_key found_key;
5335 path = btrfs_alloc_path();
5340 ref_path->lowest_level = -1;
5341 ref_path->current_level = -1;
5342 ref_path->shared_level = -1;
5346 level = ref_path->current_level - 1;
5347 while (level >= -1) {
5349 if (level < ref_path->lowest_level)
5353 bytenr = ref_path->nodes[level];
5355 bytenr = ref_path->extent_start;
5356 BUG_ON(bytenr == 0);
5358 parent = ref_path->nodes[level + 1];
5359 ref_path->nodes[level + 1] = 0;
5360 ref_path->current_level = level;
5361 BUG_ON(parent == 0);
5363 key.objectid = bytenr;
5364 key.offset = parent + 1;
5365 key.type = BTRFS_EXTENT_REF_KEY;
5367 ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0);
5372 leaf = path->nodes[0];
5373 nritems = btrfs_header_nritems(leaf);
5374 if (path->slots[0] >= nritems) {
5375 ret = btrfs_next_leaf(extent_root, path);
5380 leaf = path->nodes[0];
5383 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5384 if (found_key.objectid == bytenr &&
5385 found_key.type == BTRFS_EXTENT_REF_KEY) {
5386 if (level < ref_path->shared_level)
5387 ref_path->shared_level = level;
5392 btrfs_release_path(extent_root, path);
5395 /* reached lowest level */
5399 level = ref_path->current_level;
5400 while (level < BTRFS_MAX_LEVEL - 1) {
5404 bytenr = ref_path->nodes[level];
5406 bytenr = ref_path->extent_start;
5408 BUG_ON(bytenr == 0);
5410 key.objectid = bytenr;
5412 key.type = BTRFS_EXTENT_REF_KEY;
5414 ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0);
5418 leaf = path->nodes[0];
5419 nritems = btrfs_header_nritems(leaf);
5420 if (path->slots[0] >= nritems) {
5421 ret = btrfs_next_leaf(extent_root, path);
5425 /* the extent was freed by someone */
5426 if (ref_path->lowest_level == level)
5428 btrfs_release_path(extent_root, path);
5431 leaf = path->nodes[0];
5434 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5435 if (found_key.objectid != bytenr ||
5436 found_key.type != BTRFS_EXTENT_REF_KEY) {
5437 /* the extent was freed by someone */
5438 if (ref_path->lowest_level == level) {
5442 btrfs_release_path(extent_root, path);
5446 ref = btrfs_item_ptr(leaf, path->slots[0],
5447 struct btrfs_extent_ref);
5448 ref_objectid = btrfs_ref_objectid(leaf, ref);
5449 if (ref_objectid < BTRFS_FIRST_FREE_OBJECTID) {
5451 level = (int)ref_objectid;
5452 BUG_ON(level >= BTRFS_MAX_LEVEL);
5453 ref_path->lowest_level = level;
5454 ref_path->current_level = level;
5455 ref_path->nodes[level] = bytenr;
5457 WARN_ON(ref_objectid != level);
5460 WARN_ON(level != -1);
5464 if (ref_path->lowest_level == level) {
5465 ref_path->owner_objectid = ref_objectid;
5466 ref_path->num_refs = btrfs_ref_num_refs(leaf, ref);
5470 * the block is tree root or the block isn't in reference
5473 if (found_key.objectid == found_key.offset ||
5474 is_cowonly_root(btrfs_ref_root(leaf, ref))) {
5475 ref_path->root_objectid = btrfs_ref_root(leaf, ref);
5476 ref_path->root_generation =
5477 btrfs_ref_generation(leaf, ref);
5479 /* special reference from the tree log */
5480 ref_path->nodes[0] = found_key.offset;
5481 ref_path->current_level = 0;
5488 BUG_ON(ref_path->nodes[level] != 0);
5489 ref_path->nodes[level] = found_key.offset;
5490 ref_path->current_level = level;
5493 * the reference was created in the running transaction,
5494 * no need to continue walking up.
5496 if (btrfs_ref_generation(leaf, ref) == trans->transid) {
5497 ref_path->root_objectid = btrfs_ref_root(leaf, ref);
5498 ref_path->root_generation =
5499 btrfs_ref_generation(leaf, ref);
5504 btrfs_release_path(extent_root, path);
5507 /* reached max tree level, but no tree root found. */
5510 btrfs_free_path(path);
5514 static int btrfs_first_ref_path(struct btrfs_trans_handle *trans,
5515 struct btrfs_root *extent_root,
5516 struct btrfs_ref_path *ref_path,
5519 memset(ref_path, 0, sizeof(*ref_path));
5520 ref_path->extent_start = extent_start;
5522 return __next_ref_path(trans, extent_root, ref_path, 1);
5525 static int btrfs_next_ref_path(struct btrfs_trans_handle *trans,
5526 struct btrfs_root *extent_root,
5527 struct btrfs_ref_path *ref_path)
5529 return __next_ref_path(trans, extent_root, ref_path, 0);
5532 static noinline int get_new_locations(struct inode *reloc_inode,
5533 struct btrfs_key *extent_key,
5534 u64 offset, int no_fragment,
5535 struct disk_extent **extents,
5538 struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
5539 struct btrfs_path *path;
5540 struct btrfs_file_extent_item *fi;
5541 struct extent_buffer *leaf;
5542 struct disk_extent *exts = *extents;
5543 struct btrfs_key found_key;
5548 int max = *nr_extents;
5551 WARN_ON(!no_fragment && *extents);
5554 exts = kmalloc(sizeof(*exts) * max, GFP_NOFS);
5559 path = btrfs_alloc_path();
5562 cur_pos = extent_key->objectid - offset;
5563 last_byte = extent_key->objectid + extent_key->offset;
5564 ret = btrfs_lookup_file_extent(NULL, root, path, reloc_inode->i_ino,
5574 leaf = path->nodes[0];
5575 nritems = btrfs_header_nritems(leaf);
5576 if (path->slots[0] >= nritems) {
5577 ret = btrfs_next_leaf(root, path);
5582 leaf = path->nodes[0];
5585 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5586 if (found_key.offset != cur_pos ||
5587 found_key.type != BTRFS_EXTENT_DATA_KEY ||
5588 found_key.objectid != reloc_inode->i_ino)
5591 fi = btrfs_item_ptr(leaf, path->slots[0],
5592 struct btrfs_file_extent_item);
5593 if (btrfs_file_extent_type(leaf, fi) !=
5594 BTRFS_FILE_EXTENT_REG ||
5595 btrfs_file_extent_disk_bytenr(leaf, fi) == 0)
5599 struct disk_extent *old = exts;
5601 exts = kzalloc(sizeof(*exts) * max, GFP_NOFS);
5602 memcpy(exts, old, sizeof(*exts) * nr);
5603 if (old != *extents)
5607 exts[nr].disk_bytenr =
5608 btrfs_file_extent_disk_bytenr(leaf, fi);
5609 exts[nr].disk_num_bytes =
5610 btrfs_file_extent_disk_num_bytes(leaf, fi);
5611 exts[nr].offset = btrfs_file_extent_offset(leaf, fi);
5612 exts[nr].num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
5613 exts[nr].ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
5614 exts[nr].compression = btrfs_file_extent_compression(leaf, fi);
5615 exts[nr].encryption = btrfs_file_extent_encryption(leaf, fi);
5616 exts[nr].other_encoding = btrfs_file_extent_other_encoding(leaf,
5618 BUG_ON(exts[nr].offset > 0);
5619 BUG_ON(exts[nr].compression || exts[nr].encryption);
5620 BUG_ON(exts[nr].num_bytes != exts[nr].disk_num_bytes);
5622 cur_pos += exts[nr].num_bytes;
5625 if (cur_pos + offset >= last_byte)
5635 BUG_ON(cur_pos + offset > last_byte);
5636 if (cur_pos + offset < last_byte) {
5642 btrfs_free_path(path);
5644 if (exts != *extents)
5653 static noinline int replace_one_extent(struct btrfs_trans_handle *trans,
5654 struct btrfs_root *root,
5655 struct btrfs_path *path,
5656 struct btrfs_key *extent_key,
5657 struct btrfs_key *leaf_key,
5658 struct btrfs_ref_path *ref_path,
5659 struct disk_extent *new_extents,
5662 struct extent_buffer *leaf;
5663 struct btrfs_file_extent_item *fi;
5664 struct inode *inode = NULL;
5665 struct btrfs_key key;
5670 u64 search_end = (u64)-1;
5673 int extent_locked = 0;
5677 memcpy(&key, leaf_key, sizeof(key));
5678 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) {
5679 if (key.objectid < ref_path->owner_objectid ||
5680 (key.objectid == ref_path->owner_objectid &&
5681 key.type < BTRFS_EXTENT_DATA_KEY)) {
5682 key.objectid = ref_path->owner_objectid;
5683 key.type = BTRFS_EXTENT_DATA_KEY;
5689 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
5693 leaf = path->nodes[0];
5694 nritems = btrfs_header_nritems(leaf);
5696 if (extent_locked && ret > 0) {
5698 * the file extent item was modified by someone
5699 * before the extent got locked.
5701 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
5702 lock_end, GFP_NOFS);
5706 if (path->slots[0] >= nritems) {
5707 if (++nr_scaned > 2)
5710 BUG_ON(extent_locked);
5711 ret = btrfs_next_leaf(root, path);
5716 leaf = path->nodes[0];
5717 nritems = btrfs_header_nritems(leaf);
5720 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
5722 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) {
5723 if ((key.objectid > ref_path->owner_objectid) ||
5724 (key.objectid == ref_path->owner_objectid &&
5725 key.type > BTRFS_EXTENT_DATA_KEY) ||
5726 key.offset >= search_end)
5730 if (inode && key.objectid != inode->i_ino) {
5731 BUG_ON(extent_locked);
5732 btrfs_release_path(root, path);
5733 mutex_unlock(&inode->i_mutex);
5739 if (key.type != BTRFS_EXTENT_DATA_KEY) {
5744 fi = btrfs_item_ptr(leaf, path->slots[0],
5745 struct btrfs_file_extent_item);
5746 extent_type = btrfs_file_extent_type(leaf, fi);
5747 if ((extent_type != BTRFS_FILE_EXTENT_REG &&
5748 extent_type != BTRFS_FILE_EXTENT_PREALLOC) ||
5749 (btrfs_file_extent_disk_bytenr(leaf, fi) !=
5750 extent_key->objectid)) {
5756 num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
5757 ext_offset = btrfs_file_extent_offset(leaf, fi);
5759 if (search_end == (u64)-1) {
5760 search_end = key.offset - ext_offset +
5761 btrfs_file_extent_ram_bytes(leaf, fi);
5764 if (!extent_locked) {
5765 lock_start = key.offset;
5766 lock_end = lock_start + num_bytes - 1;
5768 if (lock_start > key.offset ||
5769 lock_end + 1 < key.offset + num_bytes) {
5770 unlock_extent(&BTRFS_I(inode)->io_tree,
5771 lock_start, lock_end, GFP_NOFS);
5777 btrfs_release_path(root, path);
5779 inode = btrfs_iget_locked(root->fs_info->sb,
5780 key.objectid, root);
5781 if (inode->i_state & I_NEW) {
5782 BTRFS_I(inode)->root = root;
5783 BTRFS_I(inode)->location.objectid =
5785 BTRFS_I(inode)->location.type =
5786 BTRFS_INODE_ITEM_KEY;
5787 BTRFS_I(inode)->location.offset = 0;
5788 btrfs_read_locked_inode(inode);
5789 unlock_new_inode(inode);
5792 * some code call btrfs_commit_transaction while
5793 * holding the i_mutex, so we can't use mutex_lock
5796 if (is_bad_inode(inode) ||
5797 !mutex_trylock(&inode->i_mutex)) {
5800 key.offset = (u64)-1;
5805 if (!extent_locked) {
5806 struct btrfs_ordered_extent *ordered;
5808 btrfs_release_path(root, path);
5810 lock_extent(&BTRFS_I(inode)->io_tree, lock_start,
5811 lock_end, GFP_NOFS);
5812 ordered = btrfs_lookup_first_ordered_extent(inode,
5815 ordered->file_offset <= lock_end &&
5816 ordered->file_offset + ordered->len > lock_start) {
5817 unlock_extent(&BTRFS_I(inode)->io_tree,
5818 lock_start, lock_end, GFP_NOFS);
5819 btrfs_start_ordered_extent(inode, ordered, 1);
5820 btrfs_put_ordered_extent(ordered);
5821 key.offset += num_bytes;
5825 btrfs_put_ordered_extent(ordered);
5831 if (nr_extents == 1) {
5832 /* update extent pointer in place */
5833 btrfs_set_file_extent_disk_bytenr(leaf, fi,
5834 new_extents[0].disk_bytenr);
5835 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
5836 new_extents[0].disk_num_bytes);
5837 btrfs_mark_buffer_dirty(leaf);
5839 btrfs_drop_extent_cache(inode, key.offset,
5840 key.offset + num_bytes - 1, 0);
5842 ret = btrfs_inc_extent_ref(trans, root,
5843 new_extents[0].disk_bytenr,
5844 new_extents[0].disk_num_bytes,
5846 root->root_key.objectid,
5851 ret = btrfs_free_extent(trans, root,
5852 extent_key->objectid,
5855 btrfs_header_owner(leaf),
5856 btrfs_header_generation(leaf),
5860 btrfs_release_path(root, path);
5861 key.offset += num_bytes;
5869 * drop old extent pointer at first, then insert the
5870 * new pointers one bye one
5872 btrfs_release_path(root, path);
5873 ret = btrfs_drop_extents(trans, root, inode, key.offset,
5874 key.offset + num_bytes,
5875 key.offset, &alloc_hint);
5878 for (i = 0; i < nr_extents; i++) {
5879 if (ext_offset >= new_extents[i].num_bytes) {
5880 ext_offset -= new_extents[i].num_bytes;
5883 extent_len = min(new_extents[i].num_bytes -
5884 ext_offset, num_bytes);
5886 ret = btrfs_insert_empty_item(trans, root,
5891 leaf = path->nodes[0];
5892 fi = btrfs_item_ptr(leaf, path->slots[0],
5893 struct btrfs_file_extent_item);
5894 btrfs_set_file_extent_generation(leaf, fi,
5896 btrfs_set_file_extent_type(leaf, fi,
5897 BTRFS_FILE_EXTENT_REG);
5898 btrfs_set_file_extent_disk_bytenr(leaf, fi,
5899 new_extents[i].disk_bytenr);
5900 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
5901 new_extents[i].disk_num_bytes);
5902 btrfs_set_file_extent_ram_bytes(leaf, fi,
5903 new_extents[i].ram_bytes);
5905 btrfs_set_file_extent_compression(leaf, fi,
5906 new_extents[i].compression);
5907 btrfs_set_file_extent_encryption(leaf, fi,
5908 new_extents[i].encryption);
5909 btrfs_set_file_extent_other_encoding(leaf, fi,
5910 new_extents[i].other_encoding);
5912 btrfs_set_file_extent_num_bytes(leaf, fi,
5914 ext_offset += new_extents[i].offset;
5915 btrfs_set_file_extent_offset(leaf, fi,
5917 btrfs_mark_buffer_dirty(leaf);
5919 btrfs_drop_extent_cache(inode, key.offset,
5920 key.offset + extent_len - 1, 0);
5922 ret = btrfs_inc_extent_ref(trans, root,
5923 new_extents[i].disk_bytenr,
5924 new_extents[i].disk_num_bytes,
5926 root->root_key.objectid,
5927 trans->transid, key.objectid);
5929 btrfs_release_path(root, path);
5931 inode_add_bytes(inode, extent_len);
5934 num_bytes -= extent_len;
5935 key.offset += extent_len;
5940 BUG_ON(i >= nr_extents);
5944 if (extent_locked) {
5945 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
5946 lock_end, GFP_NOFS);
5950 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS &&
5951 key.offset >= search_end)
5958 btrfs_release_path(root, path);
5960 mutex_unlock(&inode->i_mutex);
5961 if (extent_locked) {
5962 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
5963 lock_end, GFP_NOFS);
5970 int btrfs_reloc_tree_cache_ref(struct btrfs_trans_handle *trans,
5971 struct btrfs_root *root,
5972 struct extent_buffer *buf, u64 orig_start)
5977 BUG_ON(btrfs_header_generation(buf) != trans->transid);
5978 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
5980 level = btrfs_header_level(buf);
5982 struct btrfs_leaf_ref *ref;
5983 struct btrfs_leaf_ref *orig_ref;
5985 orig_ref = btrfs_lookup_leaf_ref(root, orig_start);
5989 ref = btrfs_alloc_leaf_ref(root, orig_ref->nritems);
5991 btrfs_free_leaf_ref(root, orig_ref);
5995 ref->nritems = orig_ref->nritems;
5996 memcpy(ref->extents, orig_ref->extents,
5997 sizeof(ref->extents[0]) * ref->nritems);
5999 btrfs_free_leaf_ref(root, orig_ref);
6001 ref->root_gen = trans->transid;
6002 ref->bytenr = buf->start;
6003 ref->owner = btrfs_header_owner(buf);
6004 ref->generation = btrfs_header_generation(buf);
6006 ret = btrfs_add_leaf_ref(root, ref, 0);
6008 btrfs_free_leaf_ref(root, ref);
6013 static noinline int invalidate_extent_cache(struct btrfs_root *root,
6014 struct extent_buffer *leaf,
6015 struct btrfs_block_group_cache *group,
6016 struct btrfs_root *target_root)
6018 struct btrfs_key key;
6019 struct inode *inode = NULL;
6020 struct btrfs_file_extent_item *fi;
6022 u64 skip_objectid = 0;
6026 nritems = btrfs_header_nritems(leaf);
6027 for (i = 0; i < nritems; i++) {
6028 btrfs_item_key_to_cpu(leaf, &key, i);
6029 if (key.objectid == skip_objectid ||
6030 key.type != BTRFS_EXTENT_DATA_KEY)
6032 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
6033 if (btrfs_file_extent_type(leaf, fi) ==
6034 BTRFS_FILE_EXTENT_INLINE)
6036 if (btrfs_file_extent_disk_bytenr(leaf, fi) == 0)
6038 if (!inode || inode->i_ino != key.objectid) {
6040 inode = btrfs_ilookup(target_root->fs_info->sb,
6041 key.objectid, target_root, 1);
6044 skip_objectid = key.objectid;
6047 num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
6049 lock_extent(&BTRFS_I(inode)->io_tree, key.offset,
6050 key.offset + num_bytes - 1, GFP_NOFS);
6051 btrfs_drop_extent_cache(inode, key.offset,
6052 key.offset + num_bytes - 1, 1);
6053 unlock_extent(&BTRFS_I(inode)->io_tree, key.offset,
6054 key.offset + num_bytes - 1, GFP_NOFS);
6061 static noinline int replace_extents_in_leaf(struct btrfs_trans_handle *trans,
6062 struct btrfs_root *root,
6063 struct extent_buffer *leaf,
6064 struct btrfs_block_group_cache *group,
6065 struct inode *reloc_inode)
6067 struct btrfs_key key;
6068 struct btrfs_key extent_key;
6069 struct btrfs_file_extent_item *fi;
6070 struct btrfs_leaf_ref *ref;
6071 struct disk_extent *new_extent;
6080 new_extent = kmalloc(sizeof(*new_extent), GFP_NOFS);
6081 BUG_ON(!new_extent);
6083 ref = btrfs_lookup_leaf_ref(root, leaf->start);
6087 nritems = btrfs_header_nritems(leaf);
6088 for (i = 0; i < nritems; i++) {
6089 btrfs_item_key_to_cpu(leaf, &key, i);
6090 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
6092 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
6093 if (btrfs_file_extent_type(leaf, fi) ==
6094 BTRFS_FILE_EXTENT_INLINE)
6096 bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
6097 num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
6102 if (bytenr >= group->key.objectid + group->key.offset ||
6103 bytenr + num_bytes <= group->key.objectid)
6106 extent_key.objectid = bytenr;
6107 extent_key.offset = num_bytes;
6108 extent_key.type = BTRFS_EXTENT_ITEM_KEY;
6110 ret = get_new_locations(reloc_inode, &extent_key,
6111 group->key.objectid, 1,
6112 &new_extent, &nr_extent);
6117 BUG_ON(ref->extents[ext_index].bytenr != bytenr);
6118 BUG_ON(ref->extents[ext_index].num_bytes != num_bytes);
6119 ref->extents[ext_index].bytenr = new_extent->disk_bytenr;
6120 ref->extents[ext_index].num_bytes = new_extent->disk_num_bytes;
6122 btrfs_set_file_extent_disk_bytenr(leaf, fi,
6123 new_extent->disk_bytenr);
6124 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
6125 new_extent->disk_num_bytes);
6126 btrfs_mark_buffer_dirty(leaf);
6128 ret = btrfs_inc_extent_ref(trans, root,
6129 new_extent->disk_bytenr,
6130 new_extent->disk_num_bytes,
6132 root->root_key.objectid,
6133 trans->transid, key.objectid);
6136 ret = btrfs_free_extent(trans, root,
6137 bytenr, num_bytes, leaf->start,
6138 btrfs_header_owner(leaf),
6139 btrfs_header_generation(leaf),
6145 BUG_ON(ext_index + 1 != ref->nritems);
6146 btrfs_free_leaf_ref(root, ref);
6150 int btrfs_free_reloc_root(struct btrfs_trans_handle *trans,
6151 struct btrfs_root *root)
6153 struct btrfs_root *reloc_root;
6156 if (root->reloc_root) {
6157 reloc_root = root->reloc_root;
6158 root->reloc_root = NULL;
6159 list_add(&reloc_root->dead_list,
6160 &root->fs_info->dead_reloc_roots);
6162 btrfs_set_root_bytenr(&reloc_root->root_item,
6163 reloc_root->node->start);
6164 btrfs_set_root_level(&root->root_item,
6165 btrfs_header_level(reloc_root->node));
6166 memset(&reloc_root->root_item.drop_progress, 0,
6167 sizeof(struct btrfs_disk_key));
6168 reloc_root->root_item.drop_level = 0;
6170 ret = btrfs_update_root(trans, root->fs_info->tree_root,
6171 &reloc_root->root_key,
6172 &reloc_root->root_item);
6178 int btrfs_drop_dead_reloc_roots(struct btrfs_root *root)
6180 struct btrfs_trans_handle *trans;
6181 struct btrfs_root *reloc_root;
6182 struct btrfs_root *prev_root = NULL;
6183 struct list_head dead_roots;
6187 INIT_LIST_HEAD(&dead_roots);
6188 list_splice_init(&root->fs_info->dead_reloc_roots, &dead_roots);
6190 while (!list_empty(&dead_roots)) {
6191 reloc_root = list_entry(dead_roots.prev,
6192 struct btrfs_root, dead_list);
6193 list_del_init(&reloc_root->dead_list);
6195 BUG_ON(reloc_root->commit_root != NULL);
6197 trans = btrfs_join_transaction(root, 1);
6200 mutex_lock(&root->fs_info->drop_mutex);
6201 ret = btrfs_drop_snapshot(trans, reloc_root);
6204 mutex_unlock(&root->fs_info->drop_mutex);
6206 nr = trans->blocks_used;
6207 ret = btrfs_end_transaction(trans, root);
6209 btrfs_btree_balance_dirty(root, nr);
6212 free_extent_buffer(reloc_root->node);
6214 ret = btrfs_del_root(trans, root->fs_info->tree_root,
6215 &reloc_root->root_key);
6217 mutex_unlock(&root->fs_info->drop_mutex);
6219 nr = trans->blocks_used;
6220 ret = btrfs_end_transaction(trans, root);
6222 btrfs_btree_balance_dirty(root, nr);
6225 prev_root = reloc_root;
6228 btrfs_remove_leaf_refs(prev_root, (u64)-1, 0);
6234 int btrfs_add_dead_reloc_root(struct btrfs_root *root)
6236 list_add(&root->dead_list, &root->fs_info->dead_reloc_roots);
6240 int btrfs_cleanup_reloc_trees(struct btrfs_root *root)
6242 struct btrfs_root *reloc_root;
6243 struct btrfs_trans_handle *trans;
6244 struct btrfs_key location;
6248 mutex_lock(&root->fs_info->tree_reloc_mutex);
6249 ret = btrfs_find_dead_roots(root, BTRFS_TREE_RELOC_OBJECTID, NULL);
6251 found = !list_empty(&root->fs_info->dead_reloc_roots);
6252 mutex_unlock(&root->fs_info->tree_reloc_mutex);
6255 trans = btrfs_start_transaction(root, 1);
6257 ret = btrfs_commit_transaction(trans, root);
6261 location.objectid = BTRFS_DATA_RELOC_TREE_OBJECTID;
6262 location.offset = (u64)-1;
6263 location.type = BTRFS_ROOT_ITEM_KEY;
6265 reloc_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
6266 BUG_ON(!reloc_root);
6267 btrfs_orphan_cleanup(reloc_root);
6271 static noinline int init_reloc_tree(struct btrfs_trans_handle *trans,
6272 struct btrfs_root *root)
6274 struct btrfs_root *reloc_root;
6275 struct extent_buffer *eb;
6276 struct btrfs_root_item *root_item;
6277 struct btrfs_key root_key;
6280 BUG_ON(!root->ref_cows);
6281 if (root->reloc_root)
6284 root_item = kmalloc(sizeof(*root_item), GFP_NOFS);
6287 ret = btrfs_copy_root(trans, root, root->commit_root,
6288 &eb, BTRFS_TREE_RELOC_OBJECTID);
6291 root_key.objectid = BTRFS_TREE_RELOC_OBJECTID;
6292 root_key.offset = root->root_key.objectid;
6293 root_key.type = BTRFS_ROOT_ITEM_KEY;
6295 memcpy(root_item, &root->root_item, sizeof(root_item));
6296 btrfs_set_root_refs(root_item, 0);
6297 btrfs_set_root_bytenr(root_item, eb->start);
6298 btrfs_set_root_level(root_item, btrfs_header_level(eb));
6299 btrfs_set_root_generation(root_item, trans->transid);
6301 btrfs_tree_unlock(eb);
6302 free_extent_buffer(eb);
6304 ret = btrfs_insert_root(trans, root->fs_info->tree_root,
6305 &root_key, root_item);
6309 reloc_root = btrfs_read_fs_root_no_radix(root->fs_info->tree_root,
6311 BUG_ON(!reloc_root);
6312 reloc_root->last_trans = trans->transid;
6313 reloc_root->commit_root = NULL;
6314 reloc_root->ref_tree = &root->fs_info->reloc_ref_tree;
6316 root->reloc_root = reloc_root;
6321 * Core function of space balance.
6323 * The idea is using reloc trees to relocate tree blocks in reference
6324 * counted roots. There is one reloc tree for each subvol, and all
6325 * reloc trees share same root key objectid. Reloc trees are snapshots
6326 * of the latest committed roots of subvols (root->commit_root).
6328 * To relocate a tree block referenced by a subvol, there are two steps.
6329 * COW the block through subvol's reloc tree, then update block pointer
6330 * in the subvol to point to the new block. Since all reloc trees share
6331 * same root key objectid, doing special handing for tree blocks owned
6332 * by them is easy. Once a tree block has been COWed in one reloc tree,
6333 * we can use the resulting new block directly when the same block is
6334 * required to COW again through other reloc trees. By this way, relocated
6335 * tree blocks are shared between reloc trees, so they are also shared
6338 static noinline int relocate_one_path(struct btrfs_trans_handle *trans,
6339 struct btrfs_root *root,
6340 struct btrfs_path *path,
6341 struct btrfs_key *first_key,
6342 struct btrfs_ref_path *ref_path,
6343 struct btrfs_block_group_cache *group,
6344 struct inode *reloc_inode)
6346 struct btrfs_root *reloc_root;
6347 struct extent_buffer *eb = NULL;
6348 struct btrfs_key *keys;
6352 int lowest_level = 0;
6355 if (ref_path->owner_objectid < BTRFS_FIRST_FREE_OBJECTID)
6356 lowest_level = ref_path->owner_objectid;
6358 if (!root->ref_cows) {
6359 path->lowest_level = lowest_level;
6360 ret = btrfs_search_slot(trans, root, first_key, path, 0, 1);
6362 path->lowest_level = 0;
6363 btrfs_release_path(root, path);
6367 mutex_lock(&root->fs_info->tree_reloc_mutex);
6368 ret = init_reloc_tree(trans, root);
6370 reloc_root = root->reloc_root;
6372 shared_level = ref_path->shared_level;
6373 ref_path->shared_level = BTRFS_MAX_LEVEL - 1;
6375 keys = ref_path->node_keys;
6376 nodes = ref_path->new_nodes;
6377 memset(&keys[shared_level + 1], 0,
6378 sizeof(*keys) * (BTRFS_MAX_LEVEL - shared_level - 1));
6379 memset(&nodes[shared_level + 1], 0,
6380 sizeof(*nodes) * (BTRFS_MAX_LEVEL - shared_level - 1));
6382 if (nodes[lowest_level] == 0) {
6383 path->lowest_level = lowest_level;
6384 ret = btrfs_search_slot(trans, reloc_root, first_key, path,
6387 for (level = lowest_level; level < BTRFS_MAX_LEVEL; level++) {
6388 eb = path->nodes[level];
6389 if (!eb || eb == reloc_root->node)
6391 nodes[level] = eb->start;
6393 btrfs_item_key_to_cpu(eb, &keys[level], 0);
6395 btrfs_node_key_to_cpu(eb, &keys[level], 0);
6398 ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
6399 eb = path->nodes[0];
6400 ret = replace_extents_in_leaf(trans, reloc_root, eb,
6401 group, reloc_inode);
6404 btrfs_release_path(reloc_root, path);
6406 ret = btrfs_merge_path(trans, reloc_root, keys, nodes,
6412 * replace tree blocks in the fs tree with tree blocks in
6415 ret = btrfs_merge_path(trans, root, keys, nodes, lowest_level);
6418 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
6419 ret = btrfs_search_slot(trans, reloc_root, first_key, path,
6422 extent_buffer_get(path->nodes[0]);
6423 eb = path->nodes[0];
6424 btrfs_release_path(reloc_root, path);
6425 ret = invalidate_extent_cache(reloc_root, eb, group, root);
6427 free_extent_buffer(eb);
6430 mutex_unlock(&root->fs_info->tree_reloc_mutex);
6431 path->lowest_level = 0;
6435 static noinline int relocate_tree_block(struct btrfs_trans_handle *trans,
6436 struct btrfs_root *root,
6437 struct btrfs_path *path,
6438 struct btrfs_key *first_key,
6439 struct btrfs_ref_path *ref_path)
6443 ret = relocate_one_path(trans, root, path, first_key,
6444 ref_path, NULL, NULL);
6450 static noinline int del_extent_zero(struct btrfs_trans_handle *trans,
6451 struct btrfs_root *extent_root,
6452 struct btrfs_path *path,
6453 struct btrfs_key *extent_key)
6457 ret = btrfs_search_slot(trans, extent_root, extent_key, path, -1, 1);
6460 ret = btrfs_del_item(trans, extent_root, path);
6462 btrfs_release_path(extent_root, path);
6466 static noinline struct btrfs_root *read_ref_root(struct btrfs_fs_info *fs_info,
6467 struct btrfs_ref_path *ref_path)
6469 struct btrfs_key root_key;
6471 root_key.objectid = ref_path->root_objectid;
6472 root_key.type = BTRFS_ROOT_ITEM_KEY;
6473 if (is_cowonly_root(ref_path->root_objectid))
6474 root_key.offset = 0;
6476 root_key.offset = (u64)-1;
6478 return btrfs_read_fs_root_no_name(fs_info, &root_key);
6481 static noinline int relocate_one_extent(struct btrfs_root *extent_root,
6482 struct btrfs_path *path,
6483 struct btrfs_key *extent_key,
6484 struct btrfs_block_group_cache *group,
6485 struct inode *reloc_inode, int pass)
6487 struct btrfs_trans_handle *trans;
6488 struct btrfs_root *found_root;
6489 struct btrfs_ref_path *ref_path = NULL;
6490 struct disk_extent *new_extents = NULL;
6495 struct btrfs_key first_key;
6499 trans = btrfs_start_transaction(extent_root, 1);
6502 if (extent_key->objectid == 0) {
6503 ret = del_extent_zero(trans, extent_root, path, extent_key);
6507 ref_path = kmalloc(sizeof(*ref_path), GFP_NOFS);
6513 for (loops = 0; ; loops++) {
6515 ret = btrfs_first_ref_path(trans, extent_root, ref_path,
6516 extent_key->objectid);
6518 ret = btrfs_next_ref_path(trans, extent_root, ref_path);
6525 if (ref_path->root_objectid == BTRFS_TREE_LOG_OBJECTID ||
6526 ref_path->root_objectid == BTRFS_TREE_RELOC_OBJECTID)
6529 found_root = read_ref_root(extent_root->fs_info, ref_path);
6530 BUG_ON(!found_root);
6532 * for reference counted tree, only process reference paths
6533 * rooted at the latest committed root.
6535 if (found_root->ref_cows &&
6536 ref_path->root_generation != found_root->root_key.offset)
6539 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
6542 * copy data extents to new locations
6544 u64 group_start = group->key.objectid;
6545 ret = relocate_data_extent(reloc_inode,
6554 level = ref_path->owner_objectid;
6557 if (prev_block != ref_path->nodes[level]) {
6558 struct extent_buffer *eb;
6559 u64 block_start = ref_path->nodes[level];
6560 u64 block_size = btrfs_level_size(found_root, level);
6562 eb = read_tree_block(found_root, block_start,
6564 btrfs_tree_lock(eb);
6565 BUG_ON(level != btrfs_header_level(eb));
6568 btrfs_item_key_to_cpu(eb, &first_key, 0);
6570 btrfs_node_key_to_cpu(eb, &first_key, 0);
6572 btrfs_tree_unlock(eb);
6573 free_extent_buffer(eb);
6574 prev_block = block_start;
6577 mutex_lock(&extent_root->fs_info->trans_mutex);
6578 btrfs_record_root_in_trans(found_root);
6579 mutex_unlock(&extent_root->fs_info->trans_mutex);
6580 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
6582 * try to update data extent references while
6583 * keeping metadata shared between snapshots.
6586 ret = relocate_one_path(trans, found_root,
6587 path, &first_key, ref_path,
6588 group, reloc_inode);
6594 * use fallback method to process the remaining
6598 u64 group_start = group->key.objectid;
6599 new_extents = kmalloc(sizeof(*new_extents),
6602 ret = get_new_locations(reloc_inode,
6610 ret = replace_one_extent(trans, found_root,
6612 &first_key, ref_path,
6613 new_extents, nr_extents);
6615 ret = relocate_tree_block(trans, found_root, path,
6616 &first_key, ref_path);
6623 btrfs_end_transaction(trans, extent_root);
6630 static u64 update_block_group_flags(struct btrfs_root *root, u64 flags)
6633 u64 stripped = BTRFS_BLOCK_GROUP_RAID0 |
6634 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
6636 num_devices = root->fs_info->fs_devices->rw_devices;
6637 if (num_devices == 1) {
6638 stripped |= BTRFS_BLOCK_GROUP_DUP;
6639 stripped = flags & ~stripped;
6641 /* turn raid0 into single device chunks */
6642 if (flags & BTRFS_BLOCK_GROUP_RAID0)
6645 /* turn mirroring into duplication */
6646 if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
6647 BTRFS_BLOCK_GROUP_RAID10))
6648 return stripped | BTRFS_BLOCK_GROUP_DUP;
6651 /* they already had raid on here, just return */
6652 if (flags & stripped)
6655 stripped |= BTRFS_BLOCK_GROUP_DUP;
6656 stripped = flags & ~stripped;
6658 /* switch duplicated blocks with raid1 */
6659 if (flags & BTRFS_BLOCK_GROUP_DUP)
6660 return stripped | BTRFS_BLOCK_GROUP_RAID1;
6662 /* turn single device chunks into raid0 */
6663 return stripped | BTRFS_BLOCK_GROUP_RAID0;
6668 static int __alloc_chunk_for_shrink(struct btrfs_root *root,
6669 struct btrfs_block_group_cache *shrink_block_group,
6672 struct btrfs_trans_handle *trans;
6673 u64 new_alloc_flags;
6676 spin_lock(&shrink_block_group->lock);
6677 if (btrfs_block_group_used(&shrink_block_group->item) +
6678 shrink_block_group->reserved > 0) {
6679 spin_unlock(&shrink_block_group->lock);
6681 trans = btrfs_start_transaction(root, 1);
6682 spin_lock(&shrink_block_group->lock);
6684 new_alloc_flags = update_block_group_flags(root,
6685 shrink_block_group->flags);
6686 if (new_alloc_flags != shrink_block_group->flags) {
6688 btrfs_block_group_used(&shrink_block_group->item);
6690 calc = shrink_block_group->key.offset;
6692 spin_unlock(&shrink_block_group->lock);
6694 do_chunk_alloc(trans, root->fs_info->extent_root,
6695 calc + 2 * 1024 * 1024, new_alloc_flags, force);
6697 btrfs_end_transaction(trans, root);
6699 spin_unlock(&shrink_block_group->lock);
6704 int btrfs_prepare_block_group_relocation(struct btrfs_root *root,
6705 struct btrfs_block_group_cache *group)
6708 __alloc_chunk_for_shrink(root, group, 1);
6709 set_block_group_readonly(group);
6714 * checks to see if its even possible to relocate this block group.
6716 * @return - -1 if it's not a good idea to relocate this block group, 0 if its
6717 * ok to go ahead and try.
6719 int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
6721 struct btrfs_block_group_cache *block_group;
6722 struct btrfs_space_info *space_info;
6723 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
6724 struct btrfs_device *device;
6728 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
6730 /* odd, couldn't find the block group, leave it alone */
6734 /* no bytes used, we're good */
6735 if (!btrfs_block_group_used(&block_group->item))
6738 space_info = block_group->space_info;
6739 spin_lock(&space_info->lock);
6741 full = space_info->full;
6744 * if this is the last block group we have in this space, we can't
6747 if (space_info->total_bytes == block_group->key.offset) {
6749 spin_unlock(&space_info->lock);
6754 * need to make sure we have room in the space to handle all of the
6755 * extents from this block group. If we can, we're good
6757 if (space_info->bytes_used + space_info->bytes_reserved +
6758 space_info->bytes_pinned + space_info->bytes_readonly +
6759 btrfs_block_group_used(&block_group->item) <
6760 space_info->total_bytes) {
6761 spin_unlock(&space_info->lock);
6764 spin_unlock(&space_info->lock);
6767 * ok we don't have enough space, but maybe we have free space on our
6768 * devices to allocate new chunks for relocation, so loop through our
6769 * alloc devices and guess if we have enough space. However, if we
6770 * were marked as full, then we know there aren't enough chunks, and we
6777 mutex_lock(&root->fs_info->chunk_mutex);
6778 list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
6779 u64 min_free = btrfs_block_group_used(&block_group->item);
6780 u64 dev_offset, max_avail;
6783 * check to make sure we can actually find a chunk with enough
6784 * space to fit our block group in.
6786 if (device->total_bytes > device->bytes_used + min_free) {
6787 ret = find_free_dev_extent(NULL, device, min_free,
6788 &dev_offset, &max_avail);
6794 mutex_unlock(&root->fs_info->chunk_mutex);
6796 btrfs_put_block_group(block_group);
6800 static int find_first_block_group(struct btrfs_root *root,
6801 struct btrfs_path *path, struct btrfs_key *key)
6804 struct btrfs_key found_key;
6805 struct extent_buffer *leaf;
6808 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
6813 slot = path->slots[0];
6814 leaf = path->nodes[0];
6815 if (slot >= btrfs_header_nritems(leaf)) {
6816 ret = btrfs_next_leaf(root, path);
6823 btrfs_item_key_to_cpu(leaf, &found_key, slot);
6825 if (found_key.objectid >= key->objectid &&
6826 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
6837 int btrfs_free_block_groups(struct btrfs_fs_info *info)
6839 struct btrfs_block_group_cache *block_group;
6840 struct btrfs_space_info *space_info;
6841 struct btrfs_caching_control *caching_ctl;
6844 down_write(&info->extent_commit_sem);
6845 while (!list_empty(&info->caching_block_groups)) {
6846 caching_ctl = list_entry(info->caching_block_groups.next,
6847 struct btrfs_caching_control, list);
6848 list_del(&caching_ctl->list);
6849 put_caching_control(caching_ctl);
6851 up_write(&info->extent_commit_sem);
6853 spin_lock(&info->block_group_cache_lock);
6854 while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
6855 block_group = rb_entry(n, struct btrfs_block_group_cache,
6857 rb_erase(&block_group->cache_node,
6858 &info->block_group_cache_tree);
6859 spin_unlock(&info->block_group_cache_lock);
6861 down_write(&block_group->space_info->groups_sem);
6862 list_del(&block_group->list);
6863 up_write(&block_group->space_info->groups_sem);
6865 if (block_group->cached == BTRFS_CACHE_STARTED)
6866 wait_block_group_cache_done(block_group);
6868 btrfs_remove_free_space_cache(block_group);
6870 WARN_ON(atomic_read(&block_group->count) != 1);
6873 spin_lock(&info->block_group_cache_lock);
6875 spin_unlock(&info->block_group_cache_lock);
6877 /* now that all the block groups are freed, go through and
6878 * free all the space_info structs. This is only called during
6879 * the final stages of unmount, and so we know nobody is
6880 * using them. We call synchronize_rcu() once before we start,
6881 * just to be on the safe side.
6885 while(!list_empty(&info->space_info)) {
6886 space_info = list_entry(info->space_info.next,
6887 struct btrfs_space_info,
6890 list_del(&space_info->list);
6896 int btrfs_read_block_groups(struct btrfs_root *root)
6898 struct btrfs_path *path;
6900 struct btrfs_block_group_cache *cache;
6901 struct btrfs_fs_info *info = root->fs_info;
6902 struct btrfs_space_info *space_info;
6903 struct btrfs_key key;
6904 struct btrfs_key found_key;
6905 struct extent_buffer *leaf;
6907 root = info->extent_root;
6910 btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
6911 path = btrfs_alloc_path();
6916 ret = find_first_block_group(root, path, &key);
6924 leaf = path->nodes[0];
6925 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6926 cache = kzalloc(sizeof(*cache), GFP_NOFS);
6932 atomic_set(&cache->count, 1);
6933 spin_lock_init(&cache->lock);
6934 spin_lock_init(&cache->tree_lock);
6935 cache->fs_info = info;
6936 INIT_LIST_HEAD(&cache->list);
6937 INIT_LIST_HEAD(&cache->cluster_list);
6940 * we only want to have 32k of ram per block group for keeping
6941 * track of free space, and if we pass 1/2 of that we want to
6942 * start converting things over to using bitmaps
6944 cache->extents_thresh = ((1024 * 32) / 2) /
6945 sizeof(struct btrfs_free_space);
6947 read_extent_buffer(leaf, &cache->item,
6948 btrfs_item_ptr_offset(leaf, path->slots[0]),
6949 sizeof(cache->item));
6950 memcpy(&cache->key, &found_key, sizeof(found_key));
6952 key.objectid = found_key.objectid + found_key.offset;
6953 btrfs_release_path(root, path);
6954 cache->flags = btrfs_block_group_flags(&cache->item);
6955 cache->sectorsize = root->sectorsize;
6958 * check for two cases, either we are full, and therefore
6959 * don't need to bother with the caching work since we won't
6960 * find any space, or we are empty, and we can just add all
6961 * the space in and be done with it. This saves us _alot_ of
6962 * time, particularly in the full case.
6964 if (found_key.offset == btrfs_block_group_used(&cache->item)) {
6965 exclude_super_stripes(root, cache);
6966 cache->last_byte_to_unpin = (u64)-1;
6967 cache->cached = BTRFS_CACHE_FINISHED;
6968 free_excluded_extents(root, cache);
6969 } else if (btrfs_block_group_used(&cache->item) == 0) {
6970 exclude_super_stripes(root, cache);
6971 cache->last_byte_to_unpin = (u64)-1;
6972 cache->cached = BTRFS_CACHE_FINISHED;
6973 add_new_free_space(cache, root->fs_info,
6975 found_key.objectid +
6977 free_excluded_extents(root, cache);
6980 ret = update_space_info(info, cache->flags, found_key.offset,
6981 btrfs_block_group_used(&cache->item),
6984 cache->space_info = space_info;
6985 spin_lock(&cache->space_info->lock);
6986 cache->space_info->bytes_super += cache->bytes_super;
6987 spin_unlock(&cache->space_info->lock);
6989 down_write(&space_info->groups_sem);
6990 list_add_tail(&cache->list, &space_info->block_groups);
6991 up_write(&space_info->groups_sem);
6993 ret = btrfs_add_block_group_cache(root->fs_info, cache);
6996 set_avail_alloc_bits(root->fs_info, cache->flags);
6997 if (btrfs_chunk_readonly(root, cache->key.objectid))
6998 set_block_group_readonly(cache);
7002 btrfs_free_path(path);
7006 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
7007 struct btrfs_root *root, u64 bytes_used,
7008 u64 type, u64 chunk_objectid, u64 chunk_offset,
7012 struct btrfs_root *extent_root;
7013 struct btrfs_block_group_cache *cache;
7015 extent_root = root->fs_info->extent_root;
7017 root->fs_info->last_trans_log_full_commit = trans->transid;
7019 cache = kzalloc(sizeof(*cache), GFP_NOFS);
7023 cache->key.objectid = chunk_offset;
7024 cache->key.offset = size;
7025 cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
7026 cache->sectorsize = root->sectorsize;
7029 * we only want to have 32k of ram per block group for keeping track
7030 * of free space, and if we pass 1/2 of that we want to start
7031 * converting things over to using bitmaps
7033 cache->extents_thresh = ((1024 * 32) / 2) /
7034 sizeof(struct btrfs_free_space);
7035 atomic_set(&cache->count, 1);
7036 spin_lock_init(&cache->lock);
7037 spin_lock_init(&cache->tree_lock);
7038 INIT_LIST_HEAD(&cache->list);
7039 INIT_LIST_HEAD(&cache->cluster_list);
7041 btrfs_set_block_group_used(&cache->item, bytes_used);
7042 btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
7043 cache->flags = type;
7044 btrfs_set_block_group_flags(&cache->item, type);
7046 cache->last_byte_to_unpin = (u64)-1;
7047 cache->cached = BTRFS_CACHE_FINISHED;
7048 exclude_super_stripes(root, cache);
7050 add_new_free_space(cache, root->fs_info, chunk_offset,
7051 chunk_offset + size);
7053 free_excluded_extents(root, cache);
7055 ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
7056 &cache->space_info);
7059 spin_lock(&cache->space_info->lock);
7060 cache->space_info->bytes_super += cache->bytes_super;
7061 spin_unlock(&cache->space_info->lock);
7063 down_write(&cache->space_info->groups_sem);
7064 list_add_tail(&cache->list, &cache->space_info->block_groups);
7065 up_write(&cache->space_info->groups_sem);
7067 ret = btrfs_add_block_group_cache(root->fs_info, cache);
7070 ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
7071 sizeof(cache->item));
7074 set_avail_alloc_bits(extent_root->fs_info, type);
7079 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
7080 struct btrfs_root *root, u64 group_start)
7082 struct btrfs_path *path;
7083 struct btrfs_block_group_cache *block_group;
7084 struct btrfs_free_cluster *cluster;
7085 struct btrfs_key key;
7088 root = root->fs_info->extent_root;
7090 block_group = btrfs_lookup_block_group(root->fs_info, group_start);
7091 BUG_ON(!block_group);
7092 BUG_ON(!block_group->ro);
7094 memcpy(&key, &block_group->key, sizeof(key));
7096 /* make sure this block group isn't part of an allocation cluster */
7097 cluster = &root->fs_info->data_alloc_cluster;
7098 spin_lock(&cluster->refill_lock);
7099 btrfs_return_cluster_to_free_space(block_group, cluster);
7100 spin_unlock(&cluster->refill_lock);
7103 * make sure this block group isn't part of a metadata
7104 * allocation cluster
7106 cluster = &root->fs_info->meta_alloc_cluster;
7107 spin_lock(&cluster->refill_lock);
7108 btrfs_return_cluster_to_free_space(block_group, cluster);
7109 spin_unlock(&cluster->refill_lock);
7111 path = btrfs_alloc_path();
7114 spin_lock(&root->fs_info->block_group_cache_lock);
7115 rb_erase(&block_group->cache_node,
7116 &root->fs_info->block_group_cache_tree);
7117 spin_unlock(&root->fs_info->block_group_cache_lock);
7119 down_write(&block_group->space_info->groups_sem);
7121 * we must use list_del_init so people can check to see if they
7122 * are still on the list after taking the semaphore
7124 list_del_init(&block_group->list);
7125 up_write(&block_group->space_info->groups_sem);
7127 if (block_group->cached == BTRFS_CACHE_STARTED)
7128 wait_block_group_cache_done(block_group);
7130 btrfs_remove_free_space_cache(block_group);
7132 spin_lock(&block_group->space_info->lock);
7133 block_group->space_info->total_bytes -= block_group->key.offset;
7134 block_group->space_info->bytes_readonly -= block_group->key.offset;
7135 spin_unlock(&block_group->space_info->lock);
7137 btrfs_clear_space_info_full(root->fs_info);
7139 btrfs_put_block_group(block_group);
7140 btrfs_put_block_group(block_group);
7142 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
7148 ret = btrfs_del_item(trans, root, path);
7150 btrfs_free_path(path);