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>
25 #include "print-tree.h"
26 #include "transaction.h"
30 #define BLOCK_GROUP_DATA EXTENT_WRITEBACK
31 #define BLOCK_GROUP_METADATA EXTENT_UPTODATE
32 #define BLOCK_GROUP_SYSTEM EXTENT_NEW
34 #define BLOCK_GROUP_DIRTY EXTENT_DIRTY
36 static int finish_current_insert(struct btrfs_trans_handle *trans, struct
37 btrfs_root *extent_root);
38 static int del_pending_extents(struct btrfs_trans_handle *trans, struct
39 btrfs_root *extent_root);
40 static struct btrfs_block_group_cache *
41 __btrfs_find_block_group(struct btrfs_root *root,
42 struct btrfs_block_group_cache *hint,
43 u64 search_start, int data, int owner);
45 void maybe_lock_mutex(struct btrfs_root *root)
47 if (root != root->fs_info->extent_root &&
48 root != root->fs_info->chunk_root &&
49 root != root->fs_info->dev_root) {
50 mutex_lock(&root->fs_info->alloc_mutex);
54 void maybe_unlock_mutex(struct btrfs_root *root)
56 if (root != root->fs_info->extent_root &&
57 root != root->fs_info->chunk_root &&
58 root != root->fs_info->dev_root) {
59 mutex_unlock(&root->fs_info->alloc_mutex);
63 static int cache_block_group(struct btrfs_root *root,
64 struct btrfs_block_group_cache *block_group)
66 struct btrfs_path *path;
69 struct extent_buffer *leaf;
70 struct extent_io_tree *free_space_cache;
80 root = root->fs_info->extent_root;
81 free_space_cache = &root->fs_info->free_space_cache;
83 if (block_group->cached)
86 path = btrfs_alloc_path();
92 * we get into deadlocks with paths held by callers of this function.
93 * since the alloc_mutex is protecting things right now, just
94 * skip the locking here
96 path->skip_locking = 1;
97 first_free = block_group->key.objectid;
98 key.objectid = block_group->key.objectid;
100 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
101 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
104 ret = btrfs_previous_item(root, path, 0, BTRFS_EXTENT_ITEM_KEY);
108 leaf = path->nodes[0];
109 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
110 if (key.objectid + key.offset > first_free)
111 first_free = key.objectid + key.offset;
114 leaf = path->nodes[0];
115 slot = path->slots[0];
116 if (slot >= btrfs_header_nritems(leaf)) {
117 ret = btrfs_next_leaf(root, path);
126 btrfs_item_key_to_cpu(leaf, &key, slot);
127 if (key.objectid < block_group->key.objectid) {
130 if (key.objectid >= block_group->key.objectid +
131 block_group->key.offset) {
135 if (btrfs_key_type(&key) == BTRFS_EXTENT_ITEM_KEY) {
140 if (key.objectid > last) {
141 hole_size = key.objectid - last;
142 set_extent_dirty(free_space_cache, last,
143 last + hole_size - 1,
146 last = key.objectid + key.offset;
154 if (block_group->key.objectid +
155 block_group->key.offset > last) {
156 hole_size = block_group->key.objectid +
157 block_group->key.offset - last;
158 set_extent_dirty(free_space_cache, last,
159 last + hole_size - 1, GFP_NOFS);
161 block_group->cached = 1;
163 btrfs_free_path(path);
167 struct btrfs_block_group_cache *btrfs_lookup_first_block_group(struct
171 struct extent_io_tree *block_group_cache;
172 struct btrfs_block_group_cache *block_group = NULL;
178 bytenr = max_t(u64, bytenr,
179 BTRFS_SUPER_INFO_OFFSET + BTRFS_SUPER_INFO_SIZE);
180 block_group_cache = &info->block_group_cache;
181 ret = find_first_extent_bit(block_group_cache,
182 bytenr, &start, &end,
183 BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA |
188 ret = get_state_private(block_group_cache, start, &ptr);
192 block_group = (struct btrfs_block_group_cache *)(unsigned long)ptr;
196 struct btrfs_block_group_cache *btrfs_lookup_block_group(struct
200 struct extent_io_tree *block_group_cache;
201 struct btrfs_block_group_cache *block_group = NULL;
207 bytenr = max_t(u64, bytenr,
208 BTRFS_SUPER_INFO_OFFSET + BTRFS_SUPER_INFO_SIZE);
209 block_group_cache = &info->block_group_cache;
210 ret = find_first_extent_bit(block_group_cache,
211 bytenr, &start, &end,
212 BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA |
217 ret = get_state_private(block_group_cache, start, &ptr);
221 block_group = (struct btrfs_block_group_cache *)(unsigned long)ptr;
222 if (block_group->key.objectid <= bytenr && bytenr <
223 block_group->key.objectid + block_group->key.offset)
228 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
230 return (cache->flags & bits) == bits;
233 static int noinline find_search_start(struct btrfs_root *root,
234 struct btrfs_block_group_cache **cache_ret,
235 u64 *start_ret, u64 num, int data)
238 struct btrfs_block_group_cache *cache = *cache_ret;
239 struct extent_io_tree *free_space_cache;
240 struct extent_state *state;
245 u64 search_start = *start_ret;
248 WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex));
249 total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
250 free_space_cache = &root->fs_info->free_space_cache;
256 ret = cache_block_group(root, cache);
261 last = max(search_start, cache->key.objectid);
262 if (!block_group_bits(cache, data) || cache->ro)
265 spin_lock_irq(&free_space_cache->lock);
266 state = find_first_extent_bit_state(free_space_cache, last, EXTENT_DIRTY);
271 spin_unlock_irq(&free_space_cache->lock);
275 start = max(last, state->start);
276 last = state->end + 1;
277 if (last - start < num) {
279 state = extent_state_next(state);
280 } while(state && !(state->state & EXTENT_DIRTY));
283 spin_unlock_irq(&free_space_cache->lock);
287 if (start + num > cache->key.objectid + cache->key.offset)
289 if (!block_group_bits(cache, data)) {
290 printk("block group bits don't match %Lu %d\n", cache->flags, data);
296 cache = btrfs_lookup_block_group(root->fs_info, search_start);
298 printk("Unable to find block group for %Lu\n", search_start);
304 last = cache->key.objectid + cache->key.offset;
306 cache = btrfs_lookup_first_block_group(root->fs_info, last);
307 if (!cache || cache->key.objectid >= total_fs_bytes) {
316 if (cache_miss && !cache->cached) {
317 cache_block_group(root, cache);
319 cache = btrfs_lookup_first_block_group(root->fs_info, last);
322 cache = __btrfs_find_block_group(root, cache, last, data, 0);
329 static u64 div_factor(u64 num, int factor)
338 static int block_group_state_bits(u64 flags)
341 if (flags & BTRFS_BLOCK_GROUP_DATA)
342 bits |= BLOCK_GROUP_DATA;
343 if (flags & BTRFS_BLOCK_GROUP_METADATA)
344 bits |= BLOCK_GROUP_METADATA;
345 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
346 bits |= BLOCK_GROUP_SYSTEM;
350 static struct btrfs_block_group_cache *
351 __btrfs_find_block_group(struct btrfs_root *root,
352 struct btrfs_block_group_cache *hint,
353 u64 search_start, int data, int owner)
355 struct btrfs_block_group_cache *cache;
356 struct extent_io_tree *block_group_cache;
357 struct btrfs_block_group_cache *found_group = NULL;
358 struct btrfs_fs_info *info = root->fs_info;
371 block_group_cache = &info->block_group_cache;
373 if (data & BTRFS_BLOCK_GROUP_METADATA)
376 bit = block_group_state_bits(data);
379 struct btrfs_block_group_cache *shint;
380 shint = btrfs_lookup_first_block_group(info, search_start);
381 if (shint && block_group_bits(shint, data) && !shint->ro) {
382 used = btrfs_block_group_used(&shint->item);
383 if (used + shint->pinned <
384 div_factor(shint->key.offset, factor)) {
389 if (hint && !hint->ro && block_group_bits(hint, data)) {
390 used = btrfs_block_group_used(&hint->item);
391 if (used + hint->pinned <
392 div_factor(hint->key.offset, factor)) {
395 last = hint->key.objectid + hint->key.offset;
398 last = max(hint->key.objectid, search_start);
404 ret = find_first_extent_bit(block_group_cache, last,
409 ret = get_state_private(block_group_cache, start, &ptr);
415 cache = (struct btrfs_block_group_cache *)(unsigned long)ptr;
416 last = cache->key.objectid + cache->key.offset;
417 used = btrfs_block_group_used(&cache->item);
419 if (!cache->ro && block_group_bits(cache, data)) {
420 free_check = div_factor(cache->key.offset, factor);
421 if (used + cache->pinned < free_check) {
433 if (!full_search && factor < 10) {
443 struct btrfs_block_group_cache *btrfs_find_block_group(struct btrfs_root *root,
444 struct btrfs_block_group_cache
445 *hint, u64 search_start,
449 struct btrfs_block_group_cache *ret;
450 mutex_lock(&root->fs_info->alloc_mutex);
451 ret = __btrfs_find_block_group(root, hint, search_start, data, owner);
452 mutex_unlock(&root->fs_info->alloc_mutex);
455 static u64 hash_extent_ref(u64 root_objectid, u64 ref_generation,
456 u64 owner, u64 owner_offset)
458 u32 high_crc = ~(u32)0;
459 u32 low_crc = ~(u32)0;
461 lenum = cpu_to_le64(root_objectid);
462 high_crc = btrfs_crc32c(high_crc, &lenum, sizeof(lenum));
463 lenum = cpu_to_le64(ref_generation);
464 low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
465 if (owner >= BTRFS_FIRST_FREE_OBJECTID) {
466 lenum = cpu_to_le64(owner);
467 low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
468 lenum = cpu_to_le64(owner_offset);
469 low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
471 return ((u64)high_crc << 32) | (u64)low_crc;
474 static int match_extent_ref(struct extent_buffer *leaf,
475 struct btrfs_extent_ref *disk_ref,
476 struct btrfs_extent_ref *cpu_ref)
481 if (cpu_ref->objectid)
482 len = sizeof(*cpu_ref);
484 len = 2 * sizeof(u64);
485 ret = memcmp_extent_buffer(leaf, cpu_ref, (unsigned long)disk_ref,
490 static int noinline lookup_extent_backref(struct btrfs_trans_handle *trans,
491 struct btrfs_root *root,
492 struct btrfs_path *path, u64 bytenr,
494 u64 ref_generation, u64 owner,
495 u64 owner_offset, int del)
498 struct btrfs_key key;
499 struct btrfs_key found_key;
500 struct btrfs_extent_ref ref;
501 struct extent_buffer *leaf;
502 struct btrfs_extent_ref *disk_ref;
506 btrfs_set_stack_ref_root(&ref, root_objectid);
507 btrfs_set_stack_ref_generation(&ref, ref_generation);
508 btrfs_set_stack_ref_objectid(&ref, owner);
509 btrfs_set_stack_ref_offset(&ref, owner_offset);
511 hash = hash_extent_ref(root_objectid, ref_generation, owner,
514 key.objectid = bytenr;
515 key.type = BTRFS_EXTENT_REF_KEY;
518 ret = btrfs_search_slot(trans, root, &key, path,
522 leaf = path->nodes[0];
524 u32 nritems = btrfs_header_nritems(leaf);
525 if (path->slots[0] >= nritems) {
526 ret2 = btrfs_next_leaf(root, path);
529 leaf = path->nodes[0];
531 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
532 if (found_key.objectid != bytenr ||
533 found_key.type != BTRFS_EXTENT_REF_KEY)
535 key.offset = found_key.offset;
537 btrfs_release_path(root, path);
541 disk_ref = btrfs_item_ptr(path->nodes[0],
543 struct btrfs_extent_ref);
544 if (match_extent_ref(path->nodes[0], disk_ref, &ref)) {
548 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
549 key.offset = found_key.offset + 1;
550 btrfs_release_path(root, path);
557 * Back reference rules. Back refs have three main goals:
559 * 1) differentiate between all holders of references to an extent so that
560 * when a reference is dropped we can make sure it was a valid reference
561 * before freeing the extent.
563 * 2) Provide enough information to quickly find the holders of an extent
564 * if we notice a given block is corrupted or bad.
566 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
567 * maintenance. This is actually the same as #2, but with a slightly
568 * different use case.
570 * File extents can be referenced by:
572 * - multiple snapshots, subvolumes, or different generations in one subvol
573 * - different files inside a single subvolume (in theory, not implemented yet)
574 * - different offsets inside a file (bookend extents in file.c)
576 * The extent ref structure has fields for:
578 * - Objectid of the subvolume root
579 * - Generation number of the tree holding the reference
580 * - objectid of the file holding the reference
581 * - offset in the file corresponding to the key holding the reference
583 * When a file extent is allocated the fields are filled in:
584 * (root_key.objectid, trans->transid, inode objectid, offset in file)
586 * When a leaf is cow'd new references are added for every file extent found
587 * in the leaf. It looks the same as the create case, but trans->transid
588 * will be different when the block is cow'd.
590 * (root_key.objectid, trans->transid, inode objectid, offset in file)
592 * When a file extent is removed either during snapshot deletion or file
593 * truncation, the corresponding back reference is found
596 * (btrfs_header_owner(leaf), btrfs_header_generation(leaf),
597 * inode objectid, offset in file)
599 * Btree extents can be referenced by:
601 * - Different subvolumes
602 * - Different generations of the same subvolume
604 * Storing sufficient information for a full reverse mapping of a btree
605 * block would require storing the lowest key of the block in the backref,
606 * and it would require updating that lowest key either before write out or
607 * every time it changed. Instead, the objectid of the lowest key is stored
608 * along with the level of the tree block. This provides a hint
609 * about where in the btree the block can be found. Searches through the
610 * btree only need to look for a pointer to that block, so they stop one
611 * level higher than the level recorded in the backref.
613 * Some btrees do not do reference counting on their extents. These
614 * include the extent tree and the tree of tree roots. Backrefs for these
615 * trees always have a generation of zero.
617 * When a tree block is created, back references are inserted:
619 * (root->root_key.objectid, trans->transid or zero, level, lowest_key_objectid)
621 * When a tree block is cow'd in a reference counted root,
622 * new back references are added for all the blocks it points to.
623 * These are of the form (trans->transid will have increased since creation):
625 * (root->root_key.objectid, trans->transid, level, lowest_key_objectid)
627 * Because the lowest_key_objectid and the level are just hints
628 * they are not used when backrefs are deleted. When a backref is deleted:
630 * if backref was for a tree root:
631 * root_objectid = root->root_key.objectid
633 * root_objectid = btrfs_header_owner(parent)
635 * (root_objectid, btrfs_header_generation(parent) or zero, 0, 0)
637 * Back Reference Key hashing:
639 * Back references have four fields, each 64 bits long. Unfortunately,
640 * This is hashed into a single 64 bit number and placed into the key offset.
641 * The key objectid corresponds to the first byte in the extent, and the
642 * key type is set to BTRFS_EXTENT_REF_KEY
644 int btrfs_insert_extent_backref(struct btrfs_trans_handle *trans,
645 struct btrfs_root *root,
646 struct btrfs_path *path, u64 bytenr,
647 u64 root_objectid, u64 ref_generation,
648 u64 owner, u64 owner_offset)
651 struct btrfs_key key;
652 struct btrfs_extent_ref ref;
653 struct btrfs_extent_ref *disk_ref;
656 btrfs_set_stack_ref_root(&ref, root_objectid);
657 btrfs_set_stack_ref_generation(&ref, ref_generation);
658 btrfs_set_stack_ref_objectid(&ref, owner);
659 btrfs_set_stack_ref_offset(&ref, owner_offset);
661 hash = hash_extent_ref(root_objectid, ref_generation, owner,
664 key.objectid = bytenr;
665 key.type = BTRFS_EXTENT_REF_KEY;
667 ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(ref));
668 while (ret == -EEXIST) {
669 disk_ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
670 struct btrfs_extent_ref);
671 if (match_extent_ref(path->nodes[0], disk_ref, &ref))
674 btrfs_release_path(root, path);
675 ret = btrfs_insert_empty_item(trans, root, path, &key,
680 disk_ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
681 struct btrfs_extent_ref);
682 write_extent_buffer(path->nodes[0], &ref, (unsigned long)disk_ref,
684 btrfs_mark_buffer_dirty(path->nodes[0]);
686 btrfs_release_path(root, path);
690 static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
691 struct btrfs_root *root,
692 u64 bytenr, u64 num_bytes,
693 u64 root_objectid, u64 ref_generation,
694 u64 owner, u64 owner_offset)
696 struct btrfs_path *path;
698 struct btrfs_key key;
699 struct extent_buffer *l;
700 struct btrfs_extent_item *item;
703 WARN_ON(num_bytes < root->sectorsize);
704 path = btrfs_alloc_path();
709 key.objectid = bytenr;
710 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
711 key.offset = num_bytes;
712 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path,
721 item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
722 refs = btrfs_extent_refs(l, item);
723 btrfs_set_extent_refs(l, item, refs + 1);
724 btrfs_mark_buffer_dirty(path->nodes[0]);
726 btrfs_release_path(root->fs_info->extent_root, path);
729 ret = btrfs_insert_extent_backref(trans, root->fs_info->extent_root,
730 path, bytenr, root_objectid,
731 ref_generation, owner, owner_offset);
733 finish_current_insert(trans, root->fs_info->extent_root);
734 del_pending_extents(trans, root->fs_info->extent_root);
736 btrfs_free_path(path);
740 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
741 struct btrfs_root *root,
742 u64 bytenr, u64 num_bytes,
743 u64 root_objectid, u64 ref_generation,
744 u64 owner, u64 owner_offset)
748 mutex_lock(&root->fs_info->alloc_mutex);
749 ret = __btrfs_inc_extent_ref(trans, root, bytenr, num_bytes,
750 root_objectid, ref_generation,
751 owner, owner_offset);
752 mutex_unlock(&root->fs_info->alloc_mutex);
756 int btrfs_extent_post_op(struct btrfs_trans_handle *trans,
757 struct btrfs_root *root)
759 finish_current_insert(trans, root->fs_info->extent_root);
760 del_pending_extents(trans, root->fs_info->extent_root);
764 static int lookup_extent_ref(struct btrfs_trans_handle *trans,
765 struct btrfs_root *root, u64 bytenr,
766 u64 num_bytes, u32 *refs)
768 struct btrfs_path *path;
770 struct btrfs_key key;
771 struct extent_buffer *l;
772 struct btrfs_extent_item *item;
774 WARN_ON(num_bytes < root->sectorsize);
775 path = btrfs_alloc_path();
777 key.objectid = bytenr;
778 key.offset = num_bytes;
779 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
780 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path,
785 btrfs_print_leaf(root, path->nodes[0]);
786 printk("failed to find block number %Lu\n", bytenr);
790 item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
791 *refs = btrfs_extent_refs(l, item);
793 btrfs_free_path(path);
797 u32 btrfs_count_snapshots_in_path(struct btrfs_root *root,
798 struct btrfs_path *count_path,
802 struct btrfs_root *extent_root = root->fs_info->extent_root;
803 struct btrfs_path *path;
807 u64 root_objectid = root->root_key.objectid;
813 struct btrfs_key key;
814 struct btrfs_key found_key;
815 struct extent_buffer *l;
816 struct btrfs_extent_item *item;
817 struct btrfs_extent_ref *ref_item;
820 /* FIXME, needs locking */
823 mutex_lock(&root->fs_info->alloc_mutex);
824 path = btrfs_alloc_path();
827 bytenr = first_extent;
829 bytenr = count_path->nodes[level]->start;
832 key.objectid = bytenr;
835 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
836 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
842 btrfs_item_key_to_cpu(l, &found_key, path->slots[0]);
844 if (found_key.objectid != bytenr ||
845 found_key.type != BTRFS_EXTENT_ITEM_KEY) {
849 item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
850 extent_refs = btrfs_extent_refs(l, item);
853 nritems = btrfs_header_nritems(l);
854 if (path->slots[0] >= nritems) {
855 ret = btrfs_next_leaf(extent_root, path);
860 btrfs_item_key_to_cpu(l, &found_key, path->slots[0]);
861 if (found_key.objectid != bytenr)
864 if (found_key.type != BTRFS_EXTENT_REF_KEY) {
870 ref_item = btrfs_item_ptr(l, path->slots[0],
871 struct btrfs_extent_ref);
872 found_objectid = btrfs_ref_root(l, ref_item);
874 if (found_objectid != root_objectid) {
879 found_owner = btrfs_ref_objectid(l, ref_item);
880 if (found_owner != expected_owner) {
885 * nasty. we don't count a reference held by
886 * the running transaction. This allows nodatacow
887 * to avoid cow most of the time
889 if (found_owner >= BTRFS_FIRST_FREE_OBJECTID &&
890 btrfs_ref_generation(l, ref_item) ==
891 root->fs_info->generation) {
899 * if there is more than one reference against a data extent,
900 * we have to assume the other ref is another snapshot
902 if (level == -1 && extent_refs > 1) {
906 if (cur_count == 0) {
910 if (level >= 0 && root->node == count_path->nodes[level])
913 btrfs_release_path(root, path);
917 btrfs_free_path(path);
918 mutex_unlock(&root->fs_info->alloc_mutex);
922 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
923 struct extent_buffer *buf)
927 struct btrfs_key key;
928 struct btrfs_file_extent_item *fi;
937 mutex_lock(&root->fs_info->alloc_mutex);
938 level = btrfs_header_level(buf);
939 nritems = btrfs_header_nritems(buf);
940 for (i = 0; i < nritems; i++) {
943 btrfs_item_key_to_cpu(buf, &key, i);
944 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
946 fi = btrfs_item_ptr(buf, i,
947 struct btrfs_file_extent_item);
948 if (btrfs_file_extent_type(buf, fi) ==
949 BTRFS_FILE_EXTENT_INLINE)
951 disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
952 if (disk_bytenr == 0)
954 ret = __btrfs_inc_extent_ref(trans, root, disk_bytenr,
955 btrfs_file_extent_disk_num_bytes(buf, fi),
956 root->root_key.objectid, trans->transid,
957 key.objectid, key.offset);
963 bytenr = btrfs_node_blockptr(buf, i);
964 btrfs_node_key_to_cpu(buf, &key, i);
965 ret = __btrfs_inc_extent_ref(trans, root, bytenr,
966 btrfs_level_size(root, level - 1),
967 root->root_key.objectid,
969 level - 1, key.objectid);
976 mutex_unlock(&root->fs_info->alloc_mutex);
981 for (i =0; i < faili; i++) {
984 btrfs_item_key_to_cpu(buf, &key, i);
985 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
987 fi = btrfs_item_ptr(buf, i,
988 struct btrfs_file_extent_item);
989 if (btrfs_file_extent_type(buf, fi) ==
990 BTRFS_FILE_EXTENT_INLINE)
992 disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
993 if (disk_bytenr == 0)
995 err = btrfs_free_extent(trans, root, disk_bytenr,
996 btrfs_file_extent_disk_num_bytes(buf,
1000 bytenr = btrfs_node_blockptr(buf, i);
1001 err = btrfs_free_extent(trans, root, bytenr,
1002 btrfs_level_size(root, level - 1), 0);
1007 mutex_unlock(&root->fs_info->alloc_mutex);
1011 static int write_one_cache_group(struct btrfs_trans_handle *trans,
1012 struct btrfs_root *root,
1013 struct btrfs_path *path,
1014 struct btrfs_block_group_cache *cache)
1018 struct btrfs_root *extent_root = root->fs_info->extent_root;
1020 struct extent_buffer *leaf;
1022 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
1027 leaf = path->nodes[0];
1028 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
1029 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
1030 btrfs_mark_buffer_dirty(leaf);
1031 btrfs_release_path(extent_root, path);
1033 finish_current_insert(trans, extent_root);
1034 pending_ret = del_pending_extents(trans, extent_root);
1043 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
1044 struct btrfs_root *root)
1046 struct extent_io_tree *block_group_cache;
1047 struct btrfs_block_group_cache *cache;
1051 struct btrfs_path *path;
1057 block_group_cache = &root->fs_info->block_group_cache;
1058 path = btrfs_alloc_path();
1062 mutex_lock(&root->fs_info->alloc_mutex);
1064 ret = find_first_extent_bit(block_group_cache, last,
1065 &start, &end, BLOCK_GROUP_DIRTY);
1070 ret = get_state_private(block_group_cache, start, &ptr);
1073 cache = (struct btrfs_block_group_cache *)(unsigned long)ptr;
1074 err = write_one_cache_group(trans, root,
1077 * if we fail to write the cache group, we want
1078 * to keep it marked dirty in hopes that a later
1085 clear_extent_bits(block_group_cache, start, end,
1086 BLOCK_GROUP_DIRTY, GFP_NOFS);
1088 btrfs_free_path(path);
1089 mutex_unlock(&root->fs_info->alloc_mutex);
1093 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
1096 struct list_head *head = &info->space_info;
1097 struct list_head *cur;
1098 struct btrfs_space_info *found;
1099 list_for_each(cur, head) {
1100 found = list_entry(cur, struct btrfs_space_info, list);
1101 if (found->flags == flags)
1108 static int update_space_info(struct btrfs_fs_info *info, u64 flags,
1109 u64 total_bytes, u64 bytes_used,
1110 struct btrfs_space_info **space_info)
1112 struct btrfs_space_info *found;
1114 found = __find_space_info(info, flags);
1116 found->total_bytes += total_bytes;
1117 found->bytes_used += bytes_used;
1119 WARN_ON(found->total_bytes < found->bytes_used);
1120 *space_info = found;
1123 found = kmalloc(sizeof(*found), GFP_NOFS);
1127 list_add(&found->list, &info->space_info);
1128 found->flags = flags;
1129 found->total_bytes = total_bytes;
1130 found->bytes_used = bytes_used;
1131 found->bytes_pinned = 0;
1133 found->force_alloc = 0;
1134 *space_info = found;
1138 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
1140 u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 |
1141 BTRFS_BLOCK_GROUP_RAID1 |
1142 BTRFS_BLOCK_GROUP_RAID10 |
1143 BTRFS_BLOCK_GROUP_DUP);
1145 if (flags & BTRFS_BLOCK_GROUP_DATA)
1146 fs_info->avail_data_alloc_bits |= extra_flags;
1147 if (flags & BTRFS_BLOCK_GROUP_METADATA)
1148 fs_info->avail_metadata_alloc_bits |= extra_flags;
1149 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
1150 fs_info->avail_system_alloc_bits |= extra_flags;
1154 static u64 reduce_alloc_profile(struct btrfs_root *root, u64 flags)
1156 u64 num_devices = root->fs_info->fs_devices->num_devices;
1158 if (num_devices == 1)
1159 flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0);
1160 if (num_devices < 4)
1161 flags &= ~BTRFS_BLOCK_GROUP_RAID10;
1163 if ((flags & BTRFS_BLOCK_GROUP_DUP) &&
1164 (flags & (BTRFS_BLOCK_GROUP_RAID1 |
1165 BTRFS_BLOCK_GROUP_RAID10))) {
1166 flags &= ~BTRFS_BLOCK_GROUP_DUP;
1169 if ((flags & BTRFS_BLOCK_GROUP_RAID1) &&
1170 (flags & BTRFS_BLOCK_GROUP_RAID10)) {
1171 flags &= ~BTRFS_BLOCK_GROUP_RAID1;
1174 if ((flags & BTRFS_BLOCK_GROUP_RAID0) &&
1175 ((flags & BTRFS_BLOCK_GROUP_RAID1) |
1176 (flags & BTRFS_BLOCK_GROUP_RAID10) |
1177 (flags & BTRFS_BLOCK_GROUP_DUP)))
1178 flags &= ~BTRFS_BLOCK_GROUP_RAID0;
1182 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
1183 struct btrfs_root *extent_root, u64 alloc_bytes,
1184 u64 flags, int force)
1186 struct btrfs_space_info *space_info;
1192 flags = reduce_alloc_profile(extent_root, flags);
1194 space_info = __find_space_info(extent_root->fs_info, flags);
1196 ret = update_space_info(extent_root->fs_info, flags,
1200 BUG_ON(!space_info);
1202 if (space_info->force_alloc) {
1204 space_info->force_alloc = 0;
1206 if (space_info->full)
1209 thresh = div_factor(space_info->total_bytes, 6);
1211 (space_info->bytes_used + space_info->bytes_pinned + alloc_bytes) <
1215 mutex_lock(&extent_root->fs_info->chunk_mutex);
1216 ret = btrfs_alloc_chunk(trans, extent_root, &start, &num_bytes, flags);
1217 if (ret == -ENOSPC) {
1218 printk("space info full %Lu\n", flags);
1219 space_info->full = 1;
1224 ret = btrfs_make_block_group(trans, extent_root, 0, flags,
1225 BTRFS_FIRST_CHUNK_TREE_OBJECTID, start, num_bytes);
1228 mutex_unlock(&extent_root->fs_info->chunk_mutex);
1233 static int update_block_group(struct btrfs_trans_handle *trans,
1234 struct btrfs_root *root,
1235 u64 bytenr, u64 num_bytes, int alloc,
1238 struct btrfs_block_group_cache *cache;
1239 struct btrfs_fs_info *info = root->fs_info;
1240 u64 total = num_bytes;
1246 WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex));
1248 cache = btrfs_lookup_block_group(info, bytenr);
1252 byte_in_group = bytenr - cache->key.objectid;
1253 WARN_ON(byte_in_group > cache->key.offset);
1254 start = cache->key.objectid;
1255 end = start + cache->key.offset - 1;
1256 set_extent_bits(&info->block_group_cache, start, end,
1257 BLOCK_GROUP_DIRTY, GFP_NOFS);
1259 old_val = btrfs_block_group_used(&cache->item);
1260 num_bytes = min(total, cache->key.offset - byte_in_group);
1262 old_val += num_bytes;
1263 cache->space_info->bytes_used += num_bytes;
1265 old_val -= num_bytes;
1266 cache->space_info->bytes_used -= num_bytes;
1268 set_extent_dirty(&info->free_space_cache,
1269 bytenr, bytenr + num_bytes - 1,
1273 btrfs_set_block_group_used(&cache->item, old_val);
1275 bytenr += num_bytes;
1280 static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
1285 ret = find_first_extent_bit(&root->fs_info->block_group_cache,
1286 search_start, &start, &end,
1287 BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA |
1288 BLOCK_GROUP_SYSTEM);
1295 static int update_pinned_extents(struct btrfs_root *root,
1296 u64 bytenr, u64 num, int pin)
1299 struct btrfs_block_group_cache *cache;
1300 struct btrfs_fs_info *fs_info = root->fs_info;
1302 WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex));
1304 set_extent_dirty(&fs_info->pinned_extents,
1305 bytenr, bytenr + num - 1, GFP_NOFS);
1307 clear_extent_dirty(&fs_info->pinned_extents,
1308 bytenr, bytenr + num - 1, GFP_NOFS);
1311 cache = btrfs_lookup_block_group(fs_info, bytenr);
1313 u64 first = first_logical_byte(root, bytenr);
1314 WARN_ON(first < bytenr);
1315 len = min(first - bytenr, num);
1317 len = min(num, cache->key.offset -
1318 (bytenr - cache->key.objectid));
1322 cache->pinned += len;
1323 cache->space_info->bytes_pinned += len;
1325 fs_info->total_pinned += len;
1328 cache->pinned -= len;
1329 cache->space_info->bytes_pinned -= len;
1331 fs_info->total_pinned -= len;
1339 int btrfs_copy_pinned(struct btrfs_root *root, struct extent_io_tree *copy)
1344 struct extent_io_tree *pinned_extents = &root->fs_info->pinned_extents;
1348 ret = find_first_extent_bit(pinned_extents, last,
1349 &start, &end, EXTENT_DIRTY);
1352 set_extent_dirty(copy, start, end, GFP_NOFS);
1358 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
1359 struct btrfs_root *root,
1360 struct extent_io_tree *unpin)
1365 struct extent_io_tree *free_space_cache;
1366 free_space_cache = &root->fs_info->free_space_cache;
1368 mutex_lock(&root->fs_info->alloc_mutex);
1370 ret = find_first_extent_bit(unpin, 0, &start, &end,
1374 update_pinned_extents(root, start, end + 1 - start, 0);
1375 clear_extent_dirty(unpin, start, end, GFP_NOFS);
1376 set_extent_dirty(free_space_cache, start, end, GFP_NOFS);
1378 mutex_unlock(&root->fs_info->alloc_mutex);
1382 static int finish_current_insert(struct btrfs_trans_handle *trans,
1383 struct btrfs_root *extent_root)
1387 struct btrfs_fs_info *info = extent_root->fs_info;
1388 struct extent_buffer *eb;
1389 struct btrfs_path *path;
1390 struct btrfs_key ins;
1391 struct btrfs_disk_key first;
1392 struct btrfs_extent_item extent_item;
1397 WARN_ON(!mutex_is_locked(&extent_root->fs_info->alloc_mutex));
1398 btrfs_set_stack_extent_refs(&extent_item, 1);
1399 btrfs_set_key_type(&ins, BTRFS_EXTENT_ITEM_KEY);
1400 path = btrfs_alloc_path();
1403 ret = find_first_extent_bit(&info->extent_ins, 0, &start,
1404 &end, EXTENT_LOCKED);
1408 ins.objectid = start;
1409 ins.offset = end + 1 - start;
1410 err = btrfs_insert_item(trans, extent_root, &ins,
1411 &extent_item, sizeof(extent_item));
1412 clear_extent_bits(&info->extent_ins, start, end, EXTENT_LOCKED,
1414 eb = read_tree_block(extent_root, ins.objectid, ins.offset,
1416 btrfs_tree_lock(eb);
1417 level = btrfs_header_level(eb);
1419 btrfs_item_key(eb, &first, 0);
1421 btrfs_node_key(eb, &first, 0);
1423 btrfs_tree_unlock(eb);
1424 free_extent_buffer(eb);
1426 * the first key is just a hint, so the race we've created
1427 * against reading it is fine
1429 err = btrfs_insert_extent_backref(trans, extent_root, path,
1430 start, extent_root->root_key.objectid,
1432 btrfs_disk_key_objectid(&first));
1435 btrfs_free_path(path);
1439 static int pin_down_bytes(struct btrfs_root *root, u64 bytenr, u32 num_bytes,
1444 WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex));
1446 struct extent_buffer *buf;
1447 buf = btrfs_find_tree_block(root, bytenr, num_bytes);
1449 if (!btrfs_try_tree_lock(buf) &&
1450 btrfs_buffer_uptodate(buf, 0)) {
1452 root->fs_info->running_transaction->transid;
1453 u64 header_transid =
1454 btrfs_header_generation(buf);
1455 if (header_transid == transid &&
1456 !btrfs_header_flag(buf,
1457 BTRFS_HEADER_FLAG_WRITTEN)) {
1458 clean_tree_block(NULL, root, buf);
1459 btrfs_tree_unlock(buf);
1460 free_extent_buffer(buf);
1463 btrfs_tree_unlock(buf);
1465 free_extent_buffer(buf);
1467 update_pinned_extents(root, bytenr, num_bytes, 1);
1469 set_extent_bits(&root->fs_info->pending_del,
1470 bytenr, bytenr + num_bytes - 1,
1471 EXTENT_LOCKED, GFP_NOFS);
1478 * remove an extent from the root, returns 0 on success
1480 static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
1481 *root, u64 bytenr, u64 num_bytes,
1482 u64 root_objectid, u64 ref_generation,
1483 u64 owner_objectid, u64 owner_offset, int pin,
1486 struct btrfs_path *path;
1487 struct btrfs_key key;
1488 struct btrfs_fs_info *info = root->fs_info;
1489 struct btrfs_root *extent_root = info->extent_root;
1490 struct extent_buffer *leaf;
1492 int extent_slot = 0;
1493 int found_extent = 0;
1495 struct btrfs_extent_item *ei;
1498 WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex));
1499 key.objectid = bytenr;
1500 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
1501 key.offset = num_bytes;
1502 path = btrfs_alloc_path();
1507 ret = lookup_extent_backref(trans, extent_root, path,
1508 bytenr, root_objectid,
1510 owner_objectid, owner_offset, 1);
1512 struct btrfs_key found_key;
1513 extent_slot = path->slots[0];
1514 while(extent_slot > 0) {
1516 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1518 if (found_key.objectid != bytenr)
1520 if (found_key.type == BTRFS_EXTENT_ITEM_KEY &&
1521 found_key.offset == num_bytes) {
1525 if (path->slots[0] - extent_slot > 5)
1529 ret = btrfs_del_item(trans, extent_root, path);
1531 btrfs_print_leaf(extent_root, path->nodes[0]);
1533 printk("Unable to find ref byte nr %Lu root %Lu "
1534 " gen %Lu owner %Lu offset %Lu\n", bytenr,
1535 root_objectid, ref_generation, owner_objectid,
1538 if (!found_extent) {
1539 btrfs_release_path(extent_root, path);
1540 ret = btrfs_search_slot(trans, extent_root, &key, path, -1, 1);
1544 extent_slot = path->slots[0];
1547 leaf = path->nodes[0];
1548 ei = btrfs_item_ptr(leaf, extent_slot,
1549 struct btrfs_extent_item);
1550 refs = btrfs_extent_refs(leaf, ei);
1553 btrfs_set_extent_refs(leaf, ei, refs);
1555 btrfs_mark_buffer_dirty(leaf);
1557 if (refs == 0 && found_extent && path->slots[0] == extent_slot + 1) {
1558 /* if the back ref and the extent are next to each other
1559 * they get deleted below in one shot
1561 path->slots[0] = extent_slot;
1563 } else if (found_extent) {
1564 /* otherwise delete the extent back ref */
1565 ret = btrfs_del_item(trans, extent_root, path);
1567 /* if refs are 0, we need to setup the path for deletion */
1569 btrfs_release_path(extent_root, path);
1570 ret = btrfs_search_slot(trans, extent_root, &key, path,
1583 ret = pin_down_bytes(root, bytenr, num_bytes, 0);
1589 /* block accounting for super block */
1590 spin_lock_irq(&info->delalloc_lock);
1591 super_used = btrfs_super_bytes_used(&info->super_copy);
1592 btrfs_set_super_bytes_used(&info->super_copy,
1593 super_used - num_bytes);
1594 spin_unlock_irq(&info->delalloc_lock);
1596 /* block accounting for root item */
1597 root_used = btrfs_root_used(&root->root_item);
1598 btrfs_set_root_used(&root->root_item,
1599 root_used - num_bytes);
1600 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
1605 ret = update_block_group(trans, root, bytenr, num_bytes, 0,
1609 btrfs_free_path(path);
1610 finish_current_insert(trans, extent_root);
1615 * find all the blocks marked as pending in the radix tree and remove
1616 * them from the extent map
1618 static int del_pending_extents(struct btrfs_trans_handle *trans, struct
1619 btrfs_root *extent_root)
1625 struct extent_io_tree *pending_del;
1626 struct extent_io_tree *pinned_extents;
1628 WARN_ON(!mutex_is_locked(&extent_root->fs_info->alloc_mutex));
1629 pending_del = &extent_root->fs_info->pending_del;
1630 pinned_extents = &extent_root->fs_info->pinned_extents;
1633 ret = find_first_extent_bit(pending_del, 0, &start, &end,
1637 update_pinned_extents(extent_root, start, end + 1 - start, 1);
1638 clear_extent_bits(pending_del, start, end, EXTENT_LOCKED,
1640 ret = __free_extent(trans, extent_root,
1641 start, end + 1 - start,
1642 extent_root->root_key.objectid,
1651 * remove an extent from the root, returns 0 on success
1653 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
1654 struct btrfs_root *root, u64 bytenr,
1655 u64 num_bytes, u64 root_objectid,
1656 u64 ref_generation, u64 owner_objectid,
1657 u64 owner_offset, int pin)
1659 struct btrfs_root *extent_root = root->fs_info->extent_root;
1663 WARN_ON(num_bytes < root->sectorsize);
1664 if (!root->ref_cows)
1667 if (root == extent_root) {
1668 pin_down_bytes(root, bytenr, num_bytes, 1);
1671 ret = __free_extent(trans, root, bytenr, num_bytes, root_objectid,
1672 ref_generation, owner_objectid, owner_offset,
1674 pending_ret = del_pending_extents(trans, root->fs_info->extent_root);
1675 return ret ? ret : pending_ret;
1678 int btrfs_free_extent(struct btrfs_trans_handle *trans,
1679 struct btrfs_root *root, u64 bytenr,
1680 u64 num_bytes, u64 root_objectid,
1681 u64 ref_generation, u64 owner_objectid,
1682 u64 owner_offset, int pin)
1686 maybe_lock_mutex(root);
1687 ret = __btrfs_free_extent(trans, root, bytenr, num_bytes,
1688 root_objectid, ref_generation,
1689 owner_objectid, owner_offset, pin);
1690 maybe_unlock_mutex(root);
1694 static u64 stripe_align(struct btrfs_root *root, u64 val)
1696 u64 mask = ((u64)root->stripesize - 1);
1697 u64 ret = (val + mask) & ~mask;
1702 * walks the btree of allocated extents and find a hole of a given size.
1703 * The key ins is changed to record the hole:
1704 * ins->objectid == block start
1705 * ins->flags = BTRFS_EXTENT_ITEM_KEY
1706 * ins->offset == number of blocks
1707 * Any available blocks before search_start are skipped.
1709 static int noinline find_free_extent(struct btrfs_trans_handle *trans,
1710 struct btrfs_root *orig_root,
1711 u64 num_bytes, u64 empty_size,
1712 u64 search_start, u64 search_end,
1713 u64 hint_byte, struct btrfs_key *ins,
1714 u64 exclude_start, u64 exclude_nr,
1718 u64 orig_search_start;
1719 struct btrfs_root * root = orig_root->fs_info->extent_root;
1720 struct btrfs_fs_info *info = root->fs_info;
1721 u64 total_needed = num_bytes;
1722 u64 *last_ptr = NULL;
1723 struct btrfs_block_group_cache *block_group;
1726 int chunk_alloc_done = 0;
1727 int empty_cluster = 2 * 1024 * 1024;
1728 int allowed_chunk_alloc = 0;
1730 WARN_ON(num_bytes < root->sectorsize);
1731 btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
1733 if (orig_root->ref_cows || empty_size)
1734 allowed_chunk_alloc = 1;
1736 if (data & BTRFS_BLOCK_GROUP_METADATA) {
1737 last_ptr = &root->fs_info->last_alloc;
1738 empty_cluster = 256 * 1024;
1741 if ((data & BTRFS_BLOCK_GROUP_DATA) && btrfs_test_opt(root, SSD)) {
1742 last_ptr = &root->fs_info->last_data_alloc;
1747 hint_byte = *last_ptr;
1749 empty_size += empty_cluster;
1753 search_start = max(search_start, first_logical_byte(root, 0));
1754 orig_search_start = search_start;
1756 if (search_end == (u64)-1)
1757 search_end = btrfs_super_total_bytes(&info->super_copy);
1760 block_group = btrfs_lookup_first_block_group(info, hint_byte);
1762 hint_byte = search_start;
1763 block_group = __btrfs_find_block_group(root, block_group,
1764 hint_byte, data, 1);
1765 if (last_ptr && *last_ptr == 0 && block_group)
1766 hint_byte = block_group->key.objectid;
1768 block_group = __btrfs_find_block_group(root,
1770 search_start, data, 1);
1772 search_start = max(search_start, hint_byte);
1774 total_needed += empty_size;
1778 block_group = btrfs_lookup_first_block_group(info,
1781 block_group = btrfs_lookup_first_block_group(info,
1784 if (full_scan && !chunk_alloc_done) {
1785 if (allowed_chunk_alloc) {
1786 do_chunk_alloc(trans, root,
1787 num_bytes + 2 * 1024 * 1024, data, 1);
1788 allowed_chunk_alloc = 0;
1789 } else if (block_group && block_group_bits(block_group, data)) {
1790 block_group->space_info->force_alloc = 1;
1792 chunk_alloc_done = 1;
1794 ret = find_search_start(root, &block_group, &search_start,
1795 total_needed, data);
1796 if (ret == -ENOSPC && last_ptr && *last_ptr) {
1798 block_group = btrfs_lookup_first_block_group(info,
1800 search_start = orig_search_start;
1801 ret = find_search_start(root, &block_group, &search_start,
1802 total_needed, data);
1809 if (last_ptr && *last_ptr && search_start != *last_ptr) {
1812 empty_size += empty_cluster;
1813 total_needed += empty_size;
1815 block_group = btrfs_lookup_first_block_group(info,
1817 search_start = orig_search_start;
1818 ret = find_search_start(root, &block_group,
1819 &search_start, total_needed, data);
1826 search_start = stripe_align(root, search_start);
1827 ins->objectid = search_start;
1828 ins->offset = num_bytes;
1830 if (ins->objectid + num_bytes >= search_end)
1833 if (ins->objectid + num_bytes >
1834 block_group->key.objectid + block_group->key.offset) {
1835 search_start = block_group->key.objectid +
1836 block_group->key.offset;
1840 if (test_range_bit(&info->extent_ins, ins->objectid,
1841 ins->objectid + num_bytes -1, EXTENT_LOCKED, 0)) {
1842 search_start = ins->objectid + num_bytes;
1846 if (test_range_bit(&info->pinned_extents, ins->objectid,
1847 ins->objectid + num_bytes -1, EXTENT_DIRTY, 0)) {
1848 search_start = ins->objectid + num_bytes;
1852 if (exclude_nr > 0 && (ins->objectid + num_bytes > exclude_start &&
1853 ins->objectid < exclude_start + exclude_nr)) {
1854 search_start = exclude_start + exclude_nr;
1858 if (!(data & BTRFS_BLOCK_GROUP_DATA)) {
1859 block_group = btrfs_lookup_block_group(info, ins->objectid);
1861 trans->block_group = block_group;
1863 ins->offset = num_bytes;
1865 *last_ptr = ins->objectid + ins->offset;
1867 btrfs_super_total_bytes(&root->fs_info->super_copy)) {
1874 if (search_start + num_bytes >= search_end) {
1876 search_start = orig_search_start;
1883 total_needed -= empty_size;
1888 block_group = btrfs_lookup_first_block_group(info, search_start);
1890 block_group = __btrfs_find_block_group(root, block_group,
1891 search_start, data, 0);
1899 * finds a free extent and does all the dirty work required for allocation
1900 * returns the key for the extent through ins, and a tree buffer for
1901 * the first block of the extent through buf.
1903 * returns 0 if everything worked, non-zero otherwise.
1905 int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
1906 struct btrfs_root *root,
1907 u64 num_bytes, u64 min_alloc_size,
1908 u64 root_objectid, u64 ref_generation,
1909 u64 owner, u64 owner_offset,
1910 u64 empty_size, u64 hint_byte,
1911 u64 search_end, struct btrfs_key *ins, u64 data)
1917 u64 search_start = 0;
1920 struct btrfs_fs_info *info = root->fs_info;
1921 struct btrfs_root *extent_root = info->extent_root;
1922 struct btrfs_extent_item *extent_item;
1923 struct btrfs_extent_ref *ref;
1924 struct btrfs_path *path;
1925 struct btrfs_key keys[2];
1927 maybe_lock_mutex(root);
1930 alloc_profile = info->avail_data_alloc_bits &
1931 info->data_alloc_profile;
1932 data = BTRFS_BLOCK_GROUP_DATA | alloc_profile;
1933 } else if (root == root->fs_info->chunk_root) {
1934 alloc_profile = info->avail_system_alloc_bits &
1935 info->system_alloc_profile;
1936 data = BTRFS_BLOCK_GROUP_SYSTEM | alloc_profile;
1938 alloc_profile = info->avail_metadata_alloc_bits &
1939 info->metadata_alloc_profile;
1940 data = BTRFS_BLOCK_GROUP_METADATA | alloc_profile;
1943 data = reduce_alloc_profile(root, data);
1945 * the only place that sets empty_size is btrfs_realloc_node, which
1946 * is not called recursively on allocations
1948 if (empty_size || root->ref_cows) {
1949 if (!(data & BTRFS_BLOCK_GROUP_METADATA)) {
1950 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
1952 BTRFS_BLOCK_GROUP_METADATA |
1953 (info->metadata_alloc_profile &
1954 info->avail_metadata_alloc_bits), 0);
1957 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
1958 num_bytes + 2 * 1024 * 1024, data, 0);
1962 WARN_ON(num_bytes < root->sectorsize);
1963 ret = find_free_extent(trans, root, num_bytes, empty_size,
1964 search_start, search_end, hint_byte, ins,
1965 trans->alloc_exclude_start,
1966 trans->alloc_exclude_nr, data);
1968 if (ret == -ENOSPC && num_bytes > min_alloc_size) {
1969 num_bytes = num_bytes >> 1;
1970 num_bytes = max(num_bytes, min_alloc_size);
1971 do_chunk_alloc(trans, root->fs_info->extent_root,
1972 num_bytes, data, 1);
1976 printk("allocation failed flags %Lu\n", data);
1983 /* block accounting for super block */
1984 spin_lock_irq(&info->delalloc_lock);
1985 super_used = btrfs_super_bytes_used(&info->super_copy);
1986 btrfs_set_super_bytes_used(&info->super_copy, super_used + num_bytes);
1987 spin_unlock_irq(&info->delalloc_lock);
1989 /* block accounting for root item */
1990 root_used = btrfs_root_used(&root->root_item);
1991 btrfs_set_root_used(&root->root_item, root_used + num_bytes);
1993 clear_extent_dirty(&root->fs_info->free_space_cache,
1994 ins->objectid, ins->objectid + ins->offset - 1,
1997 if (root == extent_root) {
1998 set_extent_bits(&root->fs_info->extent_ins, ins->objectid,
1999 ins->objectid + ins->offset - 1,
2000 EXTENT_LOCKED, GFP_NOFS);
2004 WARN_ON(trans->alloc_exclude_nr);
2005 trans->alloc_exclude_start = ins->objectid;
2006 trans->alloc_exclude_nr = ins->offset;
2008 memcpy(&keys[0], ins, sizeof(*ins));
2009 keys[1].offset = hash_extent_ref(root_objectid, ref_generation,
2010 owner, owner_offset);
2011 keys[1].objectid = ins->objectid;
2012 keys[1].type = BTRFS_EXTENT_REF_KEY;
2013 sizes[0] = sizeof(*extent_item);
2014 sizes[1] = sizeof(*ref);
2016 path = btrfs_alloc_path();
2019 ret = btrfs_insert_empty_items(trans, extent_root, path, keys,
2023 extent_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2024 struct btrfs_extent_item);
2025 btrfs_set_extent_refs(path->nodes[0], extent_item, 1);
2026 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
2027 struct btrfs_extent_ref);
2029 btrfs_set_ref_root(path->nodes[0], ref, root_objectid);
2030 btrfs_set_ref_generation(path->nodes[0], ref, ref_generation);
2031 btrfs_set_ref_objectid(path->nodes[0], ref, owner);
2032 btrfs_set_ref_offset(path->nodes[0], ref, owner_offset);
2034 btrfs_mark_buffer_dirty(path->nodes[0]);
2036 trans->alloc_exclude_start = 0;
2037 trans->alloc_exclude_nr = 0;
2038 btrfs_free_path(path);
2039 finish_current_insert(trans, extent_root);
2040 pending_ret = del_pending_extents(trans, extent_root);
2050 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1, 0);
2052 printk("update block group failed for %Lu %Lu\n",
2053 ins->objectid, ins->offset);
2057 maybe_unlock_mutex(root);
2061 * helper function to allocate a block for a given tree
2062 * returns the tree buffer or NULL.
2064 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
2065 struct btrfs_root *root,
2074 struct btrfs_key ins;
2076 struct extent_buffer *buf;
2078 ret = btrfs_alloc_extent(trans, root, blocksize, blocksize,
2079 root_objectid, ref_generation,
2080 level, first_objectid, empty_size, hint,
2084 return ERR_PTR(ret);
2086 buf = btrfs_find_create_tree_block(root, ins.objectid, blocksize);
2088 btrfs_free_extent(trans, root, ins.objectid, blocksize,
2089 root->root_key.objectid, ref_generation,
2091 return ERR_PTR(-ENOMEM);
2093 btrfs_set_header_generation(buf, trans->transid);
2094 btrfs_tree_lock(buf);
2095 clean_tree_block(trans, root, buf);
2096 btrfs_set_buffer_uptodate(buf);
2098 if (PageDirty(buf->first_page)) {
2099 printk("page %lu dirty\n", buf->first_page->index);
2103 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
2104 buf->start + buf->len - 1, GFP_NOFS);
2105 trans->blocks_used++;
2109 static int noinline drop_leaf_ref(struct btrfs_trans_handle *trans,
2110 struct btrfs_root *root,
2111 struct extent_buffer *leaf)
2114 u64 leaf_generation;
2115 struct btrfs_key key;
2116 struct btrfs_file_extent_item *fi;
2121 BUG_ON(!btrfs_is_leaf(leaf));
2122 nritems = btrfs_header_nritems(leaf);
2123 leaf_owner = btrfs_header_owner(leaf);
2124 leaf_generation = btrfs_header_generation(leaf);
2126 for (i = 0; i < nritems; i++) {
2129 btrfs_item_key_to_cpu(leaf, &key, i);
2130 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2132 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
2133 if (btrfs_file_extent_type(leaf, fi) ==
2134 BTRFS_FILE_EXTENT_INLINE)
2137 * FIXME make sure to insert a trans record that
2138 * repeats the snapshot del on crash
2140 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
2141 if (disk_bytenr == 0)
2143 ret = __btrfs_free_extent(trans, root, disk_bytenr,
2144 btrfs_file_extent_disk_num_bytes(leaf, fi),
2145 leaf_owner, leaf_generation,
2146 key.objectid, key.offset, 0);
2152 static void noinline reada_walk_down(struct btrfs_root *root,
2153 struct extent_buffer *node,
2166 nritems = btrfs_header_nritems(node);
2167 level = btrfs_header_level(node);
2171 for (i = slot; i < nritems && skipped < 32; i++) {
2172 bytenr = btrfs_node_blockptr(node, i);
2173 if (last && ((bytenr > last && bytenr - last > 32 * 1024) ||
2174 (last > bytenr && last - bytenr > 32 * 1024))) {
2178 blocksize = btrfs_level_size(root, level - 1);
2180 ret = lookup_extent_ref(NULL, root, bytenr,
2188 ret = readahead_tree_block(root, bytenr, blocksize,
2189 btrfs_node_ptr_generation(node, i));
2190 last = bytenr + blocksize;
2198 * we want to avoid as much random IO as we can with the alloc mutex
2199 * held, so drop the lock and do the lookup, then do it again with the
2202 int drop_snap_lookup_refcount(struct btrfs_root *root, u64 start, u64 len,
2205 mutex_unlock(&root->fs_info->alloc_mutex);
2206 lookup_extent_ref(NULL, root, start, len, refs);
2208 mutex_lock(&root->fs_info->alloc_mutex);
2209 return lookup_extent_ref(NULL, root, start, len, refs);
2213 * helper function for drop_snapshot, this walks down the tree dropping ref
2214 * counts as it goes.
2216 static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
2217 struct btrfs_root *root,
2218 struct btrfs_path *path, int *level)
2224 struct extent_buffer *next;
2225 struct extent_buffer *cur;
2226 struct extent_buffer *parent;
2231 mutex_lock(&root->fs_info->alloc_mutex);
2233 WARN_ON(*level < 0);
2234 WARN_ON(*level >= BTRFS_MAX_LEVEL);
2235 ret = drop_snap_lookup_refcount(root, path->nodes[*level]->start,
2236 path->nodes[*level]->len, &refs);
2242 * walk down to the last node level and free all the leaves
2244 while(*level >= 0) {
2245 WARN_ON(*level < 0);
2246 WARN_ON(*level >= BTRFS_MAX_LEVEL);
2247 cur = path->nodes[*level];
2249 if (btrfs_header_level(cur) != *level)
2252 if (path->slots[*level] >=
2253 btrfs_header_nritems(cur))
2256 ret = drop_leaf_ref(trans, root, cur);
2260 bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
2261 ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
2262 blocksize = btrfs_level_size(root, *level - 1);
2264 ret = drop_snap_lookup_refcount(root, bytenr, blocksize, &refs);
2267 parent = path->nodes[*level];
2268 root_owner = btrfs_header_owner(parent);
2269 root_gen = btrfs_header_generation(parent);
2270 path->slots[*level]++;
2271 ret = __btrfs_free_extent(trans, root, bytenr,
2272 blocksize, root_owner,
2277 next = btrfs_find_tree_block(root, bytenr, blocksize);
2278 if (!next || !btrfs_buffer_uptodate(next, ptr_gen)) {
2279 free_extent_buffer(next);
2280 mutex_unlock(&root->fs_info->alloc_mutex);
2282 if (path->slots[*level] == 0)
2283 reada_walk_down(root, cur, path->slots[*level]);
2285 next = read_tree_block(root, bytenr, blocksize,
2288 mutex_lock(&root->fs_info->alloc_mutex);
2290 /* we've dropped the lock, double check */
2291 ret = drop_snap_lookup_refcount(root, bytenr,
2295 parent = path->nodes[*level];
2296 root_owner = btrfs_header_owner(parent);
2297 root_gen = btrfs_header_generation(parent);
2299 path->slots[*level]++;
2300 free_extent_buffer(next);
2301 ret = __btrfs_free_extent(trans, root, bytenr,
2309 WARN_ON(*level <= 0);
2310 if (path->nodes[*level-1])
2311 free_extent_buffer(path->nodes[*level-1]);
2312 path->nodes[*level-1] = next;
2313 *level = btrfs_header_level(next);
2314 path->slots[*level] = 0;
2317 WARN_ON(*level < 0);
2318 WARN_ON(*level >= BTRFS_MAX_LEVEL);
2320 if (path->nodes[*level] == root->node) {
2321 root_owner = root->root_key.objectid;
2322 parent = path->nodes[*level];
2324 parent = path->nodes[*level + 1];
2325 root_owner = btrfs_header_owner(parent);
2328 root_gen = btrfs_header_generation(parent);
2329 ret = __btrfs_free_extent(trans, root, path->nodes[*level]->start,
2330 path->nodes[*level]->len,
2331 root_owner, root_gen, 0, 0, 1);
2332 free_extent_buffer(path->nodes[*level]);
2333 path->nodes[*level] = NULL;
2336 mutex_unlock(&root->fs_info->alloc_mutex);
2342 * helper for dropping snapshots. This walks back up the tree in the path
2343 * to find the first node higher up where we haven't yet gone through
2346 static int noinline walk_up_tree(struct btrfs_trans_handle *trans,
2347 struct btrfs_root *root,
2348 struct btrfs_path *path, int *level)
2352 struct btrfs_root_item *root_item = &root->root_item;
2357 for(i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
2358 slot = path->slots[i];
2359 if (slot < btrfs_header_nritems(path->nodes[i]) - 1) {
2360 struct extent_buffer *node;
2361 struct btrfs_disk_key disk_key;
2362 node = path->nodes[i];
2365 WARN_ON(*level == 0);
2366 btrfs_node_key(node, &disk_key, path->slots[i]);
2367 memcpy(&root_item->drop_progress,
2368 &disk_key, sizeof(disk_key));
2369 root_item->drop_level = i;
2372 if (path->nodes[*level] == root->node) {
2373 root_owner = root->root_key.objectid;
2375 btrfs_header_generation(path->nodes[*level]);
2377 struct extent_buffer *node;
2378 node = path->nodes[*level + 1];
2379 root_owner = btrfs_header_owner(node);
2380 root_gen = btrfs_header_generation(node);
2382 ret = btrfs_free_extent(trans, root,
2383 path->nodes[*level]->start,
2384 path->nodes[*level]->len,
2385 root_owner, root_gen, 0, 0, 1);
2387 free_extent_buffer(path->nodes[*level]);
2388 path->nodes[*level] = NULL;
2396 * drop the reference count on the tree rooted at 'snap'. This traverses
2397 * the tree freeing any blocks that have a ref count of zero after being
2400 int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root
2406 struct btrfs_path *path;
2409 struct btrfs_root_item *root_item = &root->root_item;
2411 WARN_ON(!mutex_is_locked(&root->fs_info->drop_mutex));
2412 path = btrfs_alloc_path();
2415 level = btrfs_header_level(root->node);
2417 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
2418 path->nodes[level] = root->node;
2419 extent_buffer_get(root->node);
2420 path->slots[level] = 0;
2422 struct btrfs_key key;
2423 struct btrfs_disk_key found_key;
2424 struct extent_buffer *node;
2426 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
2427 level = root_item->drop_level;
2428 path->lowest_level = level;
2429 wret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2434 node = path->nodes[level];
2435 btrfs_node_key(node, &found_key, path->slots[level]);
2436 WARN_ON(memcmp(&found_key, &root_item->drop_progress,
2437 sizeof(found_key)));
2439 * unlock our path, this is safe because only this
2440 * function is allowed to delete this snapshot
2442 for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
2443 if (path->nodes[i] && path->locks[i]) {
2445 btrfs_tree_unlock(path->nodes[i]);
2450 wret = walk_down_tree(trans, root, path, &level);
2456 wret = walk_up_tree(trans, root, path, &level);
2461 if (trans->transaction->in_commit) {
2466 for (i = 0; i <= orig_level; i++) {
2467 if (path->nodes[i]) {
2468 free_extent_buffer(path->nodes[i]);
2469 path->nodes[i] = NULL;
2473 btrfs_free_path(path);
2477 int btrfs_free_block_groups(struct btrfs_fs_info *info)
2484 mutex_lock(&info->alloc_mutex);
2486 ret = find_first_extent_bit(&info->block_group_cache, 0,
2487 &start, &end, (unsigned int)-1);
2490 ret = get_state_private(&info->block_group_cache, start, &ptr);
2492 kfree((void *)(unsigned long)ptr);
2493 clear_extent_bits(&info->block_group_cache, start,
2494 end, (unsigned int)-1, GFP_NOFS);
2497 ret = find_first_extent_bit(&info->free_space_cache, 0,
2498 &start, &end, EXTENT_DIRTY);
2501 clear_extent_dirty(&info->free_space_cache, start,
2504 mutex_unlock(&info->alloc_mutex);
2508 static unsigned long calc_ra(unsigned long start, unsigned long last,
2511 return min(last, start + nr - 1);
2514 static int noinline relocate_inode_pages(struct inode *inode, u64 start,
2519 unsigned long last_index;
2522 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2523 struct file_ra_state *ra;
2524 unsigned long total_read = 0;
2525 unsigned long ra_pages;
2526 struct btrfs_trans_handle *trans;
2528 ra = kzalloc(sizeof(*ra), GFP_NOFS);
2530 mutex_lock(&inode->i_mutex);
2531 i = start >> PAGE_CACHE_SHIFT;
2532 last_index = (start + len - 1) >> PAGE_CACHE_SHIFT;
2534 ra_pages = BTRFS_I(inode)->root->fs_info->bdi.ra_pages;
2536 file_ra_state_init(ra, inode->i_mapping);
2538 for (; i <= last_index; i++) {
2539 if (total_read % ra_pages == 0) {
2540 btrfs_force_ra(inode->i_mapping, ra, NULL, i,
2541 calc_ra(i, last_index, ra_pages));
2544 if (((u64)i << PAGE_CACHE_SHIFT) > inode->i_size)
2545 goto truncate_racing;
2547 page = grab_cache_page(inode->i_mapping, i);
2551 if (!PageUptodate(page)) {
2552 btrfs_readpage(NULL, page);
2554 if (!PageUptodate(page)) {
2556 page_cache_release(page);
2560 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
2561 ClearPageDirty(page);
2563 cancel_dirty_page(page, PAGE_CACHE_SIZE);
2565 wait_on_page_writeback(page);
2566 set_page_extent_mapped(page);
2567 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
2568 page_end = page_start + PAGE_CACHE_SIZE - 1;
2570 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
2572 set_extent_delalloc(io_tree, page_start,
2573 page_end, GFP_NOFS);
2574 set_page_dirty(page);
2576 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
2578 page_cache_release(page);
2580 balance_dirty_pages_ratelimited_nr(inode->i_mapping,
2585 trans = btrfs_start_transaction(BTRFS_I(inode)->root, 1);
2587 btrfs_add_ordered_inode(inode);
2588 btrfs_end_transaction(trans, BTRFS_I(inode)->root);
2589 mark_inode_dirty(inode);
2591 mutex_unlock(&inode->i_mutex);
2595 vmtruncate(inode, inode->i_size);
2596 balance_dirty_pages_ratelimited_nr(inode->i_mapping,
2602 * The back references tell us which tree holds a ref on a block,
2603 * but it is possible for the tree root field in the reference to
2604 * reflect the original root before a snapshot was made. In this
2605 * case we should search through all the children of a given root
2606 * to find potential holders of references on a block.
2608 * Instead, we do something a little less fancy and just search
2609 * all the roots for a given key/block combination.
2611 static int find_root_for_ref(struct btrfs_root *root,
2612 struct btrfs_path *path,
2613 struct btrfs_key *key0,
2616 struct btrfs_root **found_root,
2619 struct btrfs_key root_location;
2620 struct btrfs_root *cur_root = *found_root;
2621 struct btrfs_file_extent_item *file_extent;
2622 u64 root_search_start = BTRFS_FS_TREE_OBJECTID;
2626 root_location.offset = (u64)-1;
2627 root_location.type = BTRFS_ROOT_ITEM_KEY;
2628 path->lowest_level = level;
2631 ret = btrfs_search_slot(NULL, cur_root, key0, path, 0, 0);
2633 if (ret == 0 && file_key) {
2634 struct extent_buffer *leaf = path->nodes[0];
2635 file_extent = btrfs_item_ptr(leaf, path->slots[0],
2636 struct btrfs_file_extent_item);
2637 if (btrfs_file_extent_type(leaf, file_extent) ==
2638 BTRFS_FILE_EXTENT_REG) {
2640 btrfs_file_extent_disk_bytenr(leaf,
2643 } else if (!file_key) {
2644 if (path->nodes[level])
2645 found_bytenr = path->nodes[level]->start;
2648 btrfs_release_path(cur_root, path);
2650 if (found_bytenr == bytenr) {
2651 *found_root = cur_root;
2655 ret = btrfs_search_root(root->fs_info->tree_root,
2656 root_search_start, &root_search_start);
2660 root_location.objectid = root_search_start;
2661 cur_root = btrfs_read_fs_root_no_name(root->fs_info,
2669 path->lowest_level = 0;
2674 * note, this releases the path
2676 static int noinline relocate_one_reference(struct btrfs_root *extent_root,
2677 struct btrfs_path *path,
2678 struct btrfs_key *extent_key,
2679 u64 *last_file_objectid,
2680 u64 *last_file_offset,
2681 u64 *last_file_root,
2684 struct inode *inode;
2685 struct btrfs_root *found_root;
2686 struct btrfs_key root_location;
2687 struct btrfs_key found_key;
2688 struct btrfs_extent_ref *ref;
2696 WARN_ON(!mutex_is_locked(&extent_root->fs_info->alloc_mutex));
2698 ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
2699 struct btrfs_extent_ref);
2700 ref_root = btrfs_ref_root(path->nodes[0], ref);
2701 ref_gen = btrfs_ref_generation(path->nodes[0], ref);
2702 ref_objectid = btrfs_ref_objectid(path->nodes[0], ref);
2703 ref_offset = btrfs_ref_offset(path->nodes[0], ref);
2704 btrfs_release_path(extent_root, path);
2706 root_location.objectid = ref_root;
2708 root_location.offset = 0;
2710 root_location.offset = (u64)-1;
2711 root_location.type = BTRFS_ROOT_ITEM_KEY;
2713 found_root = btrfs_read_fs_root_no_name(extent_root->fs_info,
2715 BUG_ON(!found_root);
2716 mutex_unlock(&extent_root->fs_info->alloc_mutex);
2718 if (ref_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
2719 found_key.objectid = ref_objectid;
2720 found_key.type = BTRFS_EXTENT_DATA_KEY;
2721 found_key.offset = ref_offset;
2724 if (last_extent == extent_key->objectid &&
2725 *last_file_objectid == ref_objectid &&
2726 *last_file_offset == ref_offset &&
2727 *last_file_root == ref_root)
2730 ret = find_root_for_ref(extent_root, path, &found_key,
2731 level, 1, &found_root,
2732 extent_key->objectid);
2737 if (last_extent == extent_key->objectid &&
2738 *last_file_objectid == ref_objectid &&
2739 *last_file_offset == ref_offset &&
2740 *last_file_root == ref_root)
2743 inode = btrfs_iget_locked(extent_root->fs_info->sb,
2744 ref_objectid, found_root);
2745 if (inode->i_state & I_NEW) {
2746 /* the inode and parent dir are two different roots */
2747 BTRFS_I(inode)->root = found_root;
2748 BTRFS_I(inode)->location.objectid = ref_objectid;
2749 BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY;
2750 BTRFS_I(inode)->location.offset = 0;
2751 btrfs_read_locked_inode(inode);
2752 unlock_new_inode(inode);
2755 /* this can happen if the reference is not against
2756 * the latest version of the tree root
2758 if (is_bad_inode(inode))
2761 *last_file_objectid = inode->i_ino;
2762 *last_file_root = found_root->root_key.objectid;
2763 *last_file_offset = ref_offset;
2765 relocate_inode_pages(inode, ref_offset, extent_key->offset);
2768 struct btrfs_trans_handle *trans;
2769 struct extent_buffer *eb;
2772 eb = read_tree_block(found_root, extent_key->objectid,
2773 extent_key->offset, 0);
2774 btrfs_tree_lock(eb);
2775 level = btrfs_header_level(eb);
2778 btrfs_item_key_to_cpu(eb, &found_key, 0);
2780 btrfs_node_key_to_cpu(eb, &found_key, 0);
2782 btrfs_tree_unlock(eb);
2783 free_extent_buffer(eb);
2785 ret = find_root_for_ref(extent_root, path, &found_key,
2786 level, 0, &found_root,
2787 extent_key->objectid);
2793 * right here almost anything could happen to our key,
2794 * but that's ok. The cow below will either relocate it
2795 * or someone else will have relocated it. Either way,
2796 * it is in a different spot than it was before and
2800 trans = btrfs_start_transaction(found_root, 1);
2802 if (found_root == extent_root->fs_info->extent_root ||
2803 found_root == extent_root->fs_info->chunk_root ||
2804 found_root == extent_root->fs_info->dev_root) {
2806 mutex_lock(&extent_root->fs_info->alloc_mutex);
2809 path->lowest_level = level;
2811 ret = btrfs_search_slot(trans, found_root, &found_key, path,
2813 path->lowest_level = 0;
2814 btrfs_release_path(found_root, path);
2816 if (found_root == found_root->fs_info->extent_root)
2817 btrfs_extent_post_op(trans, found_root);
2819 mutex_unlock(&extent_root->fs_info->alloc_mutex);
2821 btrfs_end_transaction(trans, found_root);
2825 mutex_lock(&extent_root->fs_info->alloc_mutex);
2829 static int noinline del_extent_zero(struct btrfs_root *extent_root,
2830 struct btrfs_path *path,
2831 struct btrfs_key *extent_key)
2834 struct btrfs_trans_handle *trans;
2836 trans = btrfs_start_transaction(extent_root, 1);
2837 ret = btrfs_search_slot(trans, extent_root, extent_key, path, -1, 1);
2844 ret = btrfs_del_item(trans, extent_root, path);
2846 btrfs_end_transaction(trans, extent_root);
2850 static int noinline relocate_one_extent(struct btrfs_root *extent_root,
2851 struct btrfs_path *path,
2852 struct btrfs_key *extent_key)
2854 struct btrfs_key key;
2855 struct btrfs_key found_key;
2856 struct extent_buffer *leaf;
2857 u64 last_file_objectid = 0;
2858 u64 last_file_root = 0;
2859 u64 last_file_offset = (u64)-1;
2860 u64 last_extent = 0;
2865 if (extent_key->objectid == 0) {
2866 ret = del_extent_zero(extent_root, path, extent_key);
2869 key.objectid = extent_key->objectid;
2870 key.type = BTRFS_EXTENT_REF_KEY;
2874 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
2880 leaf = path->nodes[0];
2881 nritems = btrfs_header_nritems(leaf);
2882 if (path->slots[0] == nritems) {
2883 ret = btrfs_next_leaf(extent_root, path);
2890 leaf = path->nodes[0];
2893 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2894 if (found_key.objectid != extent_key->objectid) {
2898 if (found_key.type != BTRFS_EXTENT_REF_KEY) {
2902 key.offset = found_key.offset + 1;
2903 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2905 ret = relocate_one_reference(extent_root, path, extent_key,
2906 &last_file_objectid,
2908 &last_file_root, last_extent);
2911 last_extent = extent_key->objectid;
2915 btrfs_release_path(extent_root, path);
2919 static u64 update_block_group_flags(struct btrfs_root *root, u64 flags)
2922 u64 stripped = BTRFS_BLOCK_GROUP_RAID0 |
2923 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
2925 num_devices = root->fs_info->fs_devices->num_devices;
2926 if (num_devices == 1) {
2927 stripped |= BTRFS_BLOCK_GROUP_DUP;
2928 stripped = flags & ~stripped;
2930 /* turn raid0 into single device chunks */
2931 if (flags & BTRFS_BLOCK_GROUP_RAID0)
2934 /* turn mirroring into duplication */
2935 if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
2936 BTRFS_BLOCK_GROUP_RAID10))
2937 return stripped | BTRFS_BLOCK_GROUP_DUP;
2940 /* they already had raid on here, just return */
2941 if (flags & stripped)
2944 stripped |= BTRFS_BLOCK_GROUP_DUP;
2945 stripped = flags & ~stripped;
2947 /* switch duplicated blocks with raid1 */
2948 if (flags & BTRFS_BLOCK_GROUP_DUP)
2949 return stripped | BTRFS_BLOCK_GROUP_RAID1;
2951 /* turn single device chunks into raid0 */
2952 return stripped | BTRFS_BLOCK_GROUP_RAID0;
2957 int __alloc_chunk_for_shrink(struct btrfs_root *root,
2958 struct btrfs_block_group_cache *shrink_block_group,
2961 struct btrfs_trans_handle *trans;
2962 u64 new_alloc_flags;
2965 if (btrfs_block_group_used(&shrink_block_group->item) > 0) {
2967 mutex_unlock(&root->fs_info->alloc_mutex);
2968 trans = btrfs_start_transaction(root, 1);
2969 mutex_lock(&root->fs_info->alloc_mutex);
2971 new_alloc_flags = update_block_group_flags(root,
2972 shrink_block_group->flags);
2973 if (new_alloc_flags != shrink_block_group->flags) {
2975 btrfs_block_group_used(&shrink_block_group->item);
2977 calc = shrink_block_group->key.offset;
2979 do_chunk_alloc(trans, root->fs_info->extent_root,
2980 calc + 2 * 1024 * 1024, new_alloc_flags, force);
2982 mutex_unlock(&root->fs_info->alloc_mutex);
2983 btrfs_end_transaction(trans, root);
2984 mutex_lock(&root->fs_info->alloc_mutex);
2989 int btrfs_shrink_extent_tree(struct btrfs_root *root, u64 shrink_start)
2991 struct btrfs_trans_handle *trans;
2992 struct btrfs_root *tree_root = root->fs_info->tree_root;
2993 struct btrfs_path *path;
2996 u64 shrink_last_byte;
2997 struct btrfs_block_group_cache *shrink_block_group;
2998 struct btrfs_fs_info *info = root->fs_info;
2999 struct btrfs_key key;
3000 struct btrfs_key found_key;
3001 struct extent_buffer *leaf;
3006 mutex_lock(&root->fs_info->alloc_mutex);
3007 shrink_block_group = btrfs_lookup_block_group(root->fs_info,
3009 BUG_ON(!shrink_block_group);
3011 shrink_last_byte = shrink_block_group->key.objectid +
3012 shrink_block_group->key.offset;
3014 shrink_block_group->space_info->total_bytes -=
3015 shrink_block_group->key.offset;
3016 path = btrfs_alloc_path();
3017 root = root->fs_info->extent_root;
3020 printk("btrfs relocating block group %llu flags %llu\n",
3021 (unsigned long long)shrink_start,
3022 (unsigned long long)shrink_block_group->flags);
3024 __alloc_chunk_for_shrink(root, shrink_block_group, 1);
3028 shrink_block_group->ro = 1;
3032 key.objectid = shrink_start;
3035 cur_byte = key.objectid;
3037 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3041 ret = btrfs_previous_item(root, path, 0, BTRFS_EXTENT_ITEM_KEY);
3046 leaf = path->nodes[0];
3047 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3048 if (found_key.objectid + found_key.offset > shrink_start &&
3049 found_key.objectid < shrink_last_byte) {
3050 cur_byte = found_key.objectid;
3051 key.objectid = cur_byte;
3054 btrfs_release_path(root, path);
3057 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3062 leaf = path->nodes[0];
3063 nritems = btrfs_header_nritems(leaf);
3064 if (path->slots[0] >= nritems) {
3065 ret = btrfs_next_leaf(root, path);
3072 leaf = path->nodes[0];
3073 nritems = btrfs_header_nritems(leaf);
3076 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3078 if (found_key.objectid >= shrink_last_byte)
3081 if (progress && need_resched()) {
3082 memcpy(&key, &found_key, sizeof(key));
3084 btrfs_release_path(root, path);
3085 btrfs_search_slot(NULL, root, &key, path, 0, 0);
3091 if (btrfs_key_type(&found_key) != BTRFS_EXTENT_ITEM_KEY ||
3092 found_key.objectid + found_key.offset <= cur_byte) {
3093 memcpy(&key, &found_key, sizeof(key));
3100 cur_byte = found_key.objectid + found_key.offset;
3101 key.objectid = cur_byte;
3102 btrfs_release_path(root, path);
3103 ret = relocate_one_extent(root, path, &found_key);
3104 __alloc_chunk_for_shrink(root, shrink_block_group, 0);
3107 btrfs_release_path(root, path);
3109 if (total_found > 0) {
3110 printk("btrfs relocate found %llu last extent was %llu\n",
3111 (unsigned long long)total_found,
3112 (unsigned long long)found_key.objectid);
3113 mutex_unlock(&root->fs_info->alloc_mutex);
3114 trans = btrfs_start_transaction(tree_root, 1);
3115 btrfs_commit_transaction(trans, tree_root);
3117 btrfs_clean_old_snapshots(tree_root);
3119 trans = btrfs_start_transaction(tree_root, 1);
3120 btrfs_commit_transaction(trans, tree_root);
3121 mutex_lock(&root->fs_info->alloc_mutex);
3126 * we've freed all the extents, now remove the block
3127 * group item from the tree
3129 mutex_unlock(&root->fs_info->alloc_mutex);
3131 trans = btrfs_start_transaction(root, 1);
3132 mutex_lock(&root->fs_info->alloc_mutex);
3133 memcpy(&key, &shrink_block_group->key, sizeof(key));
3135 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
3141 clear_extent_bits(&info->block_group_cache, key.objectid,
3142 key.objectid + key.offset - 1,
3143 (unsigned int)-1, GFP_NOFS);
3146 clear_extent_bits(&info->free_space_cache,
3147 key.objectid, key.objectid + key.offset - 1,
3148 (unsigned int)-1, GFP_NOFS);
3150 memset(shrink_block_group, 0, sizeof(*shrink_block_group));
3151 kfree(shrink_block_group);
3153 btrfs_del_item(trans, root, path);
3154 btrfs_release_path(root, path);
3155 mutex_unlock(&root->fs_info->alloc_mutex);
3156 btrfs_commit_transaction(trans, root);
3158 mutex_lock(&root->fs_info->alloc_mutex);
3160 /* the code to unpin extents might set a few bits in the free
3161 * space cache for this range again
3163 clear_extent_bits(&info->free_space_cache,
3164 key.objectid, key.objectid + key.offset - 1,
3165 (unsigned int)-1, GFP_NOFS);
3167 btrfs_free_path(path);
3168 mutex_unlock(&root->fs_info->alloc_mutex);
3172 int find_first_block_group(struct btrfs_root *root, struct btrfs_path *path,
3173 struct btrfs_key *key)
3176 struct btrfs_key found_key;
3177 struct extent_buffer *leaf;
3180 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
3185 slot = path->slots[0];
3186 leaf = path->nodes[0];
3187 if (slot >= btrfs_header_nritems(leaf)) {
3188 ret = btrfs_next_leaf(root, path);
3195 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3197 if (found_key.objectid >= key->objectid &&
3198 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
3209 int btrfs_read_block_groups(struct btrfs_root *root)
3211 struct btrfs_path *path;
3214 struct btrfs_block_group_cache *cache;
3215 struct btrfs_fs_info *info = root->fs_info;
3216 struct btrfs_space_info *space_info;
3217 struct extent_io_tree *block_group_cache;
3218 struct btrfs_key key;
3219 struct btrfs_key found_key;
3220 struct extent_buffer *leaf;
3222 block_group_cache = &info->block_group_cache;
3223 root = info->extent_root;
3226 btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
3227 path = btrfs_alloc_path();
3231 mutex_lock(&root->fs_info->alloc_mutex);
3233 ret = find_first_block_group(root, path, &key);
3241 leaf = path->nodes[0];
3242 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3243 cache = kzalloc(sizeof(*cache), GFP_NOFS);
3249 read_extent_buffer(leaf, &cache->item,
3250 btrfs_item_ptr_offset(leaf, path->slots[0]),
3251 sizeof(cache->item));
3252 memcpy(&cache->key, &found_key, sizeof(found_key));
3254 key.objectid = found_key.objectid + found_key.offset;
3255 btrfs_release_path(root, path);
3256 cache->flags = btrfs_block_group_flags(&cache->item);
3258 if (cache->flags & BTRFS_BLOCK_GROUP_DATA) {
3259 bit = BLOCK_GROUP_DATA;
3260 } else if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM) {
3261 bit = BLOCK_GROUP_SYSTEM;
3262 } else if (cache->flags & BTRFS_BLOCK_GROUP_METADATA) {
3263 bit = BLOCK_GROUP_METADATA;
3265 set_avail_alloc_bits(info, cache->flags);
3267 ret = update_space_info(info, cache->flags, found_key.offset,
3268 btrfs_block_group_used(&cache->item),
3271 cache->space_info = space_info;
3273 /* use EXTENT_LOCKED to prevent merging */
3274 set_extent_bits(block_group_cache, found_key.objectid,
3275 found_key.objectid + found_key.offset - 1,
3276 bit | EXTENT_LOCKED, GFP_NOFS);
3277 set_state_private(block_group_cache, found_key.objectid,
3278 (unsigned long)cache);
3281 btrfs_super_total_bytes(&info->super_copy))
3286 btrfs_free_path(path);
3287 mutex_unlock(&root->fs_info->alloc_mutex);
3291 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
3292 struct btrfs_root *root, u64 bytes_used,
3293 u64 type, u64 chunk_objectid, u64 chunk_offset,
3298 struct btrfs_root *extent_root;
3299 struct btrfs_block_group_cache *cache;
3300 struct extent_io_tree *block_group_cache;
3302 WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex));
3303 extent_root = root->fs_info->extent_root;
3304 block_group_cache = &root->fs_info->block_group_cache;
3306 cache = kzalloc(sizeof(*cache), GFP_NOFS);
3308 cache->key.objectid = chunk_offset;
3309 cache->key.offset = size;
3310 btrfs_set_key_type(&cache->key, BTRFS_BLOCK_GROUP_ITEM_KEY);
3312 btrfs_set_block_group_used(&cache->item, bytes_used);
3313 btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
3314 cache->flags = type;
3315 btrfs_set_block_group_flags(&cache->item, type);
3317 ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
3318 &cache->space_info);
3321 bit = block_group_state_bits(type);
3322 set_extent_bits(block_group_cache, chunk_offset,
3323 chunk_offset + size - 1,
3324 bit | EXTENT_LOCKED, GFP_NOFS);
3326 set_state_private(block_group_cache, chunk_offset,
3327 (unsigned long)cache);
3328 ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
3329 sizeof(cache->item));
3332 finish_current_insert(trans, extent_root);
3333 ret = del_pending_extents(trans, extent_root);
3335 set_avail_alloc_bits(extent_root->fs_info, type);