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"
29 #define BLOCK_GROUP_DATA EXTENT_WRITEBACK
30 #define BLOCK_GROUP_METADATA EXTENT_UPTODATE
31 #define BLOCK_GROUP_SYSTEM EXTENT_NEW
33 #define BLOCK_GROUP_DIRTY EXTENT_DIRTY
35 static int finish_current_insert(struct btrfs_trans_handle *trans, struct
36 btrfs_root *extent_root);
37 static int del_pending_extents(struct btrfs_trans_handle *trans, struct
38 btrfs_root *extent_root);
41 static int cache_block_group(struct btrfs_root *root,
42 struct btrfs_block_group_cache *block_group)
44 struct btrfs_path *path;
47 struct extent_buffer *leaf;
48 struct extent_io_tree *free_space_cache;
58 root = root->fs_info->extent_root;
59 free_space_cache = &root->fs_info->free_space_cache;
61 if (block_group->cached)
64 path = btrfs_alloc_path();
69 first_free = block_group->key.objectid;
70 key.objectid = block_group->key.objectid;
72 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
73 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
76 ret = btrfs_previous_item(root, path, 0, BTRFS_EXTENT_ITEM_KEY);
80 leaf = path->nodes[0];
81 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
82 if (key.objectid + key.offset > first_free)
83 first_free = key.objectid + key.offset;
86 leaf = path->nodes[0];
87 slot = path->slots[0];
88 if (slot >= btrfs_header_nritems(leaf)) {
89 ret = btrfs_next_leaf(root, path);
98 btrfs_item_key_to_cpu(leaf, &key, slot);
99 if (key.objectid < block_group->key.objectid) {
102 if (key.objectid >= block_group->key.objectid +
103 block_group->key.offset) {
107 if (btrfs_key_type(&key) == BTRFS_EXTENT_ITEM_KEY) {
112 if (key.objectid > last) {
113 hole_size = key.objectid - last;
114 set_extent_dirty(free_space_cache, last,
115 last + hole_size - 1,
118 last = key.objectid + key.offset;
126 if (block_group->key.objectid +
127 block_group->key.offset > last) {
128 hole_size = block_group->key.objectid +
129 block_group->key.offset - last;
130 set_extent_dirty(free_space_cache, last,
131 last + hole_size - 1, GFP_NOFS);
133 block_group->cached = 1;
135 btrfs_free_path(path);
139 struct btrfs_block_group_cache *btrfs_lookup_block_group(struct
143 struct extent_io_tree *block_group_cache;
144 struct btrfs_block_group_cache *block_group = NULL;
150 bytenr = max_t(u64, bytenr,
151 BTRFS_SUPER_INFO_OFFSET + BTRFS_SUPER_INFO_SIZE);
152 block_group_cache = &info->block_group_cache;
153 ret = find_first_extent_bit(block_group_cache,
154 bytenr, &start, &end,
155 BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA |
160 ret = get_state_private(block_group_cache, start, &ptr);
164 block_group = (struct btrfs_block_group_cache *)(unsigned long)ptr;
165 if (block_group->key.objectid <= bytenr && bytenr <
166 block_group->key.objectid + block_group->key.offset)
171 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
173 return (cache->flags & bits) == bits;
176 static int noinline find_search_start(struct btrfs_root *root,
177 struct btrfs_block_group_cache **cache_ret,
178 u64 *start_ret, int num, int data)
181 struct btrfs_block_group_cache *cache = *cache_ret;
182 struct extent_io_tree *free_space_cache;
183 struct extent_state *state;
188 u64 search_start = *start_ret;
194 total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
195 free_space_cache = &root->fs_info->free_space_cache;
198 ret = cache_block_group(root, cache);
202 last = max(search_start, cache->key.objectid);
203 if (!block_group_bits(cache, data) || cache->ro) {
207 spin_lock_irq(&free_space_cache->lock);
208 state = find_first_extent_bit_state(free_space_cache, last, EXTENT_DIRTY);
213 spin_unlock_irq(&free_space_cache->lock);
217 start = max(last, state->start);
218 last = state->end + 1;
219 if (last - start < num) {
220 if (last == cache->key.objectid + cache->key.offset)
223 state = extent_state_next(state);
224 } while(state && !(state->state & EXTENT_DIRTY));
227 spin_unlock_irq(&free_space_cache->lock);
230 if (start + num > cache->key.objectid + cache->key.offset)
232 if (start + num > total_fs_bytes)
234 if (!block_group_bits(cache, data)) {
235 printk("block group bits don't match %Lu %d\n", cache->flags, data);
241 cache = btrfs_lookup_block_group(root->fs_info, search_start);
243 printk("Unable to find block group for %Lu\n", search_start);
249 last = cache->key.objectid + cache->key.offset;
251 cache = btrfs_lookup_block_group(root->fs_info, last);
252 if (!cache || cache->key.objectid >= total_fs_bytes) {
261 if (cache_miss && !cache->cached) {
262 cache_block_group(root, cache);
264 cache = btrfs_lookup_block_group(root->fs_info, last);
266 cache = btrfs_find_block_group(root, cache, last, data, 0);
274 static u64 div_factor(u64 num, int factor)
283 static int block_group_state_bits(u64 flags)
286 if (flags & BTRFS_BLOCK_GROUP_DATA)
287 bits |= BLOCK_GROUP_DATA;
288 if (flags & BTRFS_BLOCK_GROUP_METADATA)
289 bits |= BLOCK_GROUP_METADATA;
290 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
291 bits |= BLOCK_GROUP_SYSTEM;
295 struct btrfs_block_group_cache *btrfs_find_block_group(struct btrfs_root *root,
296 struct btrfs_block_group_cache
297 *hint, u64 search_start,
300 struct btrfs_block_group_cache *cache;
301 struct extent_io_tree *block_group_cache;
302 struct btrfs_block_group_cache *found_group = NULL;
303 struct btrfs_fs_info *info = root->fs_info;
317 block_group_cache = &info->block_group_cache;
318 total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
320 if (data & BTRFS_BLOCK_GROUP_METADATA)
323 bit = block_group_state_bits(data);
325 if (search_start && search_start < total_fs_bytes) {
326 struct btrfs_block_group_cache *shint;
327 shint = btrfs_lookup_block_group(info, search_start);
328 if (shint && block_group_bits(shint, data) && !shint->ro) {
329 used = btrfs_block_group_used(&shint->item);
330 if (used + shint->pinned <
331 div_factor(shint->key.offset, factor)) {
336 if (hint && !hint->ro && block_group_bits(hint, data) &&
337 hint->key.objectid < total_fs_bytes) {
338 used = btrfs_block_group_used(&hint->item);
339 if (used + hint->pinned <
340 div_factor(hint->key.offset, factor)) {
343 last = hint->key.objectid + hint->key.offset;
347 hint_last = max(hint->key.objectid, search_start);
349 hint_last = search_start;
351 if (hint_last >= total_fs_bytes)
352 hint_last = search_start;
357 ret = find_first_extent_bit(block_group_cache, last,
362 ret = get_state_private(block_group_cache, start, &ptr);
366 cache = (struct btrfs_block_group_cache *)(unsigned long)ptr;
367 last = cache->key.objectid + cache->key.offset;
368 used = btrfs_block_group_used(&cache->item);
370 if (cache->key.objectid > total_fs_bytes)
373 if (!cache->ro && block_group_bits(cache, data)) {
375 free_check = cache->key.offset;
377 free_check = div_factor(cache->key.offset,
380 if (used + cache->pinned < free_check) {
396 static u64 hash_extent_ref(u64 root_objectid, u64 ref_generation,
397 u64 owner, u64 owner_offset)
399 u32 high_crc = ~(u32)0;
400 u32 low_crc = ~(u32)0;
402 lenum = cpu_to_le64(root_objectid);
403 high_crc = btrfs_crc32c(high_crc, &lenum, sizeof(lenum));
404 lenum = cpu_to_le64(ref_generation);
405 low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
406 if (owner >= BTRFS_FIRST_FREE_OBJECTID) {
407 lenum = cpu_to_le64(owner);
408 low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
409 lenum = cpu_to_le64(owner_offset);
410 low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
412 return ((u64)high_crc << 32) | (u64)low_crc;
415 static int match_extent_ref(struct extent_buffer *leaf,
416 struct btrfs_extent_ref *disk_ref,
417 struct btrfs_extent_ref *cpu_ref)
422 if (cpu_ref->objectid)
423 len = sizeof(*cpu_ref);
425 len = 2 * sizeof(u64);
426 ret = memcmp_extent_buffer(leaf, cpu_ref, (unsigned long)disk_ref,
431 static int noinline lookup_extent_backref(struct btrfs_trans_handle *trans,
432 struct btrfs_root *root,
433 struct btrfs_path *path, u64 bytenr,
435 u64 ref_generation, u64 owner,
436 u64 owner_offset, int del)
439 struct btrfs_key key;
440 struct btrfs_key found_key;
441 struct btrfs_extent_ref ref;
442 struct extent_buffer *leaf;
443 struct btrfs_extent_ref *disk_ref;
447 btrfs_set_stack_ref_root(&ref, root_objectid);
448 btrfs_set_stack_ref_generation(&ref, ref_generation);
449 btrfs_set_stack_ref_objectid(&ref, owner);
450 btrfs_set_stack_ref_offset(&ref, owner_offset);
452 hash = hash_extent_ref(root_objectid, ref_generation, owner,
455 key.objectid = bytenr;
456 key.type = BTRFS_EXTENT_REF_KEY;
459 ret = btrfs_search_slot(trans, root, &key, path,
463 leaf = path->nodes[0];
465 u32 nritems = btrfs_header_nritems(leaf);
466 if (path->slots[0] >= nritems) {
467 ret2 = btrfs_next_leaf(root, path);
470 leaf = path->nodes[0];
472 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
473 if (found_key.objectid != bytenr ||
474 found_key.type != BTRFS_EXTENT_REF_KEY)
476 key.offset = found_key.offset;
478 btrfs_release_path(root, path);
482 disk_ref = btrfs_item_ptr(path->nodes[0],
484 struct btrfs_extent_ref);
485 if (match_extent_ref(path->nodes[0], disk_ref, &ref)) {
489 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
490 key.offset = found_key.offset + 1;
491 btrfs_release_path(root, path);
498 * Back reference rules. Back refs have three main goals:
500 * 1) differentiate between all holders of references to an extent so that
501 * when a reference is dropped we can make sure it was a valid reference
502 * before freeing the extent.
504 * 2) Provide enough information to quickly find the holders of an extent
505 * if we notice a given block is corrupted or bad.
507 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
508 * maintenance. This is actually the same as #2, but with a slightly
509 * different use case.
511 * File extents can be referenced by:
513 * - multiple snapshots, subvolumes, or different generations in one subvol
514 * - different files inside a single subvolume (in theory, not implemented yet)
515 * - different offsets inside a file (bookend extents in file.c)
517 * The extent ref structure has fields for:
519 * - Objectid of the subvolume root
520 * - Generation number of the tree holding the reference
521 * - objectid of the file holding the reference
522 * - offset in the file corresponding to the key holding the reference
524 * When a file extent is allocated the fields are filled in:
525 * (root_key.objectid, trans->transid, inode objectid, offset in file)
527 * When a leaf is cow'd new references are added for every file extent found
528 * in the leaf. It looks the same as the create case, but trans->transid
529 * will be different when the block is cow'd.
531 * (root_key.objectid, trans->transid, inode objectid, offset in file)
533 * When a file extent is removed either during snapshot deletion or file
534 * truncation, the corresponding back reference is found
537 * (btrfs_header_owner(leaf), btrfs_header_generation(leaf),
538 * inode objectid, offset in file)
540 * Btree extents can be referenced by:
542 * - Different subvolumes
543 * - Different generations of the same subvolume
545 * Storing sufficient information for a full reverse mapping of a btree
546 * block would require storing the lowest key of the block in the backref,
547 * and it would require updating that lowest key either before write out or
548 * every time it changed. Instead, the objectid of the lowest key is stored
549 * along with the level of the tree block. This provides a hint
550 * about where in the btree the block can be found. Searches through the
551 * btree only need to look for a pointer to that block, so they stop one
552 * level higher than the level recorded in the backref.
554 * Some btrees do not do reference counting on their extents. These
555 * include the extent tree and the tree of tree roots. Backrefs for these
556 * trees always have a generation of zero.
558 * When a tree block is created, back references are inserted:
560 * (root->root_key.objectid, trans->transid or zero, level, lowest_key_objectid)
562 * When a tree block is cow'd in a reference counted root,
563 * new back references are added for all the blocks it points to.
564 * These are of the form (trans->transid will have increased since creation):
566 * (root->root_key.objectid, trans->transid, level, lowest_key_objectid)
568 * Because the lowest_key_objectid and the level are just hints
569 * they are not used when backrefs are deleted. When a backref is deleted:
571 * if backref was for a tree root:
572 * root_objectid = root->root_key.objectid
574 * root_objectid = btrfs_header_owner(parent)
576 * (root_objectid, btrfs_header_generation(parent) or zero, 0, 0)
578 * Back Reference Key hashing:
580 * Back references have four fields, each 64 bits long. Unfortunately,
581 * This is hashed into a single 64 bit number and placed into the key offset.
582 * The key objectid corresponds to the first byte in the extent, and the
583 * key type is set to BTRFS_EXTENT_REF_KEY
585 int btrfs_insert_extent_backref(struct btrfs_trans_handle *trans,
586 struct btrfs_root *root,
587 struct btrfs_path *path, u64 bytenr,
588 u64 root_objectid, u64 ref_generation,
589 u64 owner, u64 owner_offset)
592 struct btrfs_key key;
593 struct btrfs_extent_ref ref;
594 struct btrfs_extent_ref *disk_ref;
597 btrfs_set_stack_ref_root(&ref, root_objectid);
598 btrfs_set_stack_ref_generation(&ref, ref_generation);
599 btrfs_set_stack_ref_objectid(&ref, owner);
600 btrfs_set_stack_ref_offset(&ref, owner_offset);
602 hash = hash_extent_ref(root_objectid, ref_generation, owner,
605 key.objectid = bytenr;
606 key.type = BTRFS_EXTENT_REF_KEY;
608 ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(ref));
609 while (ret == -EEXIST) {
610 disk_ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
611 struct btrfs_extent_ref);
612 if (match_extent_ref(path->nodes[0], disk_ref, &ref))
615 btrfs_release_path(root, path);
616 ret = btrfs_insert_empty_item(trans, root, path, &key,
621 disk_ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
622 struct btrfs_extent_ref);
623 write_extent_buffer(path->nodes[0], &ref, (unsigned long)disk_ref,
625 btrfs_mark_buffer_dirty(path->nodes[0]);
627 btrfs_release_path(root, path);
631 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
632 struct btrfs_root *root,
633 u64 bytenr, u64 num_bytes,
634 u64 root_objectid, u64 ref_generation,
635 u64 owner, u64 owner_offset)
637 struct btrfs_path *path;
639 struct btrfs_key key;
640 struct extent_buffer *l;
641 struct btrfs_extent_item *item;
644 WARN_ON(num_bytes < root->sectorsize);
645 path = btrfs_alloc_path();
650 key.objectid = bytenr;
651 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
652 key.offset = num_bytes;
653 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path,
662 item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
663 refs = btrfs_extent_refs(l, item);
664 btrfs_set_extent_refs(l, item, refs + 1);
665 btrfs_mark_buffer_dirty(path->nodes[0]);
667 btrfs_release_path(root->fs_info->extent_root, path);
670 ret = btrfs_insert_extent_backref(trans, root->fs_info->extent_root,
671 path, bytenr, root_objectid,
672 ref_generation, owner, owner_offset);
674 finish_current_insert(trans, root->fs_info->extent_root);
675 del_pending_extents(trans, root->fs_info->extent_root);
677 btrfs_free_path(path);
681 int btrfs_extent_post_op(struct btrfs_trans_handle *trans,
682 struct btrfs_root *root)
684 finish_current_insert(trans, root->fs_info->extent_root);
685 del_pending_extents(trans, root->fs_info->extent_root);
689 static int lookup_extent_ref(struct btrfs_trans_handle *trans,
690 struct btrfs_root *root, u64 bytenr,
691 u64 num_bytes, u32 *refs)
693 struct btrfs_path *path;
695 struct btrfs_key key;
696 struct extent_buffer *l;
697 struct btrfs_extent_item *item;
699 WARN_ON(num_bytes < root->sectorsize);
700 path = btrfs_alloc_path();
702 key.objectid = bytenr;
703 key.offset = num_bytes;
704 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
705 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path,
710 btrfs_print_leaf(root, path->nodes[0]);
711 printk("failed to find block number %Lu\n", bytenr);
715 item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
716 *refs = btrfs_extent_refs(l, item);
718 btrfs_free_path(path);
722 u32 btrfs_count_snapshots_in_path(struct btrfs_root *root,
723 struct btrfs_path *count_path,
727 struct btrfs_root *extent_root = root->fs_info->extent_root;
728 struct btrfs_path *path;
732 u64 root_objectid = root->root_key.objectid;
738 struct btrfs_key key;
739 struct btrfs_key found_key;
740 struct extent_buffer *l;
741 struct btrfs_extent_item *item;
742 struct btrfs_extent_ref *ref_item;
745 path = btrfs_alloc_path();
748 bytenr = first_extent;
750 bytenr = count_path->nodes[level]->start;
753 key.objectid = bytenr;
756 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
757 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
763 btrfs_item_key_to_cpu(l, &found_key, path->slots[0]);
765 if (found_key.objectid != bytenr ||
766 found_key.type != BTRFS_EXTENT_ITEM_KEY) {
770 item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
771 extent_refs = btrfs_extent_refs(l, item);
774 nritems = btrfs_header_nritems(l);
775 if (path->slots[0] >= nritems) {
776 ret = btrfs_next_leaf(extent_root, path);
781 btrfs_item_key_to_cpu(l, &found_key, path->slots[0]);
782 if (found_key.objectid != bytenr)
785 if (found_key.type != BTRFS_EXTENT_REF_KEY) {
791 ref_item = btrfs_item_ptr(l, path->slots[0],
792 struct btrfs_extent_ref);
793 found_objectid = btrfs_ref_root(l, ref_item);
795 if (found_objectid != root_objectid) {
800 found_owner = btrfs_ref_objectid(l, ref_item);
801 if (found_owner != expected_owner) {
806 * nasty. we don't count a reference held by
807 * the running transaction. This allows nodatacow
808 * to avoid cow most of the time
810 if (found_owner >= BTRFS_FIRST_FREE_OBJECTID &&
811 btrfs_ref_generation(l, ref_item) ==
812 root->fs_info->generation) {
820 * if there is more than one reference against a data extent,
821 * we have to assume the other ref is another snapshot
823 if (level == -1 && extent_refs > 1) {
827 if (cur_count == 0) {
831 if (level >= 0 && root->node == count_path->nodes[level])
834 btrfs_release_path(root, path);
838 btrfs_free_path(path);
841 int btrfs_inc_root_ref(struct btrfs_trans_handle *trans,
842 struct btrfs_root *root, u64 owner_objectid)
848 struct btrfs_disk_key disk_key;
850 level = btrfs_header_level(root->node);
851 generation = trans->transid;
852 nritems = btrfs_header_nritems(root->node);
855 btrfs_item_key(root->node, &disk_key, 0);
857 btrfs_node_key(root->node, &disk_key, 0);
858 key_objectid = btrfs_disk_key_objectid(&disk_key);
862 return btrfs_inc_extent_ref(trans, root, root->node->start,
863 root->node->len, owner_objectid,
864 generation, level, key_objectid);
867 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
868 struct extent_buffer *buf)
872 struct btrfs_key key;
873 struct btrfs_file_extent_item *fi;
882 level = btrfs_header_level(buf);
883 nritems = btrfs_header_nritems(buf);
884 for (i = 0; i < nritems; i++) {
887 btrfs_item_key_to_cpu(buf, &key, i);
888 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
890 fi = btrfs_item_ptr(buf, i,
891 struct btrfs_file_extent_item);
892 if (btrfs_file_extent_type(buf, fi) ==
893 BTRFS_FILE_EXTENT_INLINE)
895 disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
896 if (disk_bytenr == 0)
898 ret = btrfs_inc_extent_ref(trans, root, disk_bytenr,
899 btrfs_file_extent_disk_num_bytes(buf, fi),
900 root->root_key.objectid, trans->transid,
901 key.objectid, key.offset);
907 bytenr = btrfs_node_blockptr(buf, i);
908 btrfs_node_key_to_cpu(buf, &key, i);
909 ret = btrfs_inc_extent_ref(trans, root, bytenr,
910 btrfs_level_size(root, level - 1),
911 root->root_key.objectid,
913 level - 1, key.objectid);
924 for (i =0; i < faili; i++) {
927 btrfs_item_key_to_cpu(buf, &key, i);
928 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
930 fi = btrfs_item_ptr(buf, i,
931 struct btrfs_file_extent_item);
932 if (btrfs_file_extent_type(buf, fi) ==
933 BTRFS_FILE_EXTENT_INLINE)
935 disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
936 if (disk_bytenr == 0)
938 err = btrfs_free_extent(trans, root, disk_bytenr,
939 btrfs_file_extent_disk_num_bytes(buf,
943 bytenr = btrfs_node_blockptr(buf, i);
944 err = btrfs_free_extent(trans, root, bytenr,
945 btrfs_level_size(root, level - 1), 0);
953 static int write_one_cache_group(struct btrfs_trans_handle *trans,
954 struct btrfs_root *root,
955 struct btrfs_path *path,
956 struct btrfs_block_group_cache *cache)
960 struct btrfs_root *extent_root = root->fs_info->extent_root;
962 struct extent_buffer *leaf;
964 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
969 leaf = path->nodes[0];
970 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
971 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
972 btrfs_mark_buffer_dirty(leaf);
973 btrfs_release_path(extent_root, path);
975 finish_current_insert(trans, extent_root);
976 pending_ret = del_pending_extents(trans, extent_root);
985 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
986 struct btrfs_root *root)
988 struct extent_io_tree *block_group_cache;
989 struct btrfs_block_group_cache *cache;
993 struct btrfs_path *path;
999 block_group_cache = &root->fs_info->block_group_cache;
1000 path = btrfs_alloc_path();
1005 ret = find_first_extent_bit(block_group_cache, last,
1006 &start, &end, BLOCK_GROUP_DIRTY);
1011 ret = get_state_private(block_group_cache, start, &ptr);
1014 cache = (struct btrfs_block_group_cache *)(unsigned long)ptr;
1015 err = write_one_cache_group(trans, root,
1018 * if we fail to write the cache group, we want
1019 * to keep it marked dirty in hopes that a later
1026 clear_extent_bits(block_group_cache, start, end,
1027 BLOCK_GROUP_DIRTY, GFP_NOFS);
1029 btrfs_free_path(path);
1033 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
1036 struct list_head *head = &info->space_info;
1037 struct list_head *cur;
1038 struct btrfs_space_info *found;
1039 list_for_each(cur, head) {
1040 found = list_entry(cur, struct btrfs_space_info, list);
1041 if (found->flags == flags)
1048 static int update_space_info(struct btrfs_fs_info *info, u64 flags,
1049 u64 total_bytes, u64 bytes_used,
1050 struct btrfs_space_info **space_info)
1052 struct btrfs_space_info *found;
1054 found = __find_space_info(info, flags);
1056 found->total_bytes += total_bytes;
1057 found->bytes_used += bytes_used;
1059 WARN_ON(found->total_bytes < found->bytes_used);
1060 *space_info = found;
1063 found = kmalloc(sizeof(*found), GFP_NOFS);
1067 list_add(&found->list, &info->space_info);
1068 found->flags = flags;
1069 found->total_bytes = total_bytes;
1070 found->bytes_used = bytes_used;
1071 found->bytes_pinned = 0;
1073 *space_info = found;
1077 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
1079 u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 |
1080 BTRFS_BLOCK_GROUP_RAID1 |
1081 BTRFS_BLOCK_GROUP_RAID10 |
1082 BTRFS_BLOCK_GROUP_DUP);
1084 if (flags & BTRFS_BLOCK_GROUP_DATA)
1085 fs_info->avail_data_alloc_bits |= extra_flags;
1086 if (flags & BTRFS_BLOCK_GROUP_METADATA)
1087 fs_info->avail_metadata_alloc_bits |= extra_flags;
1088 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
1089 fs_info->avail_system_alloc_bits |= extra_flags;
1093 static u64 reduce_alloc_profile(struct btrfs_root *root, u64 flags)
1095 u64 num_devices = root->fs_info->fs_devices->num_devices;
1097 if (num_devices == 1)
1098 flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0);
1099 if (num_devices < 4)
1100 flags &= ~BTRFS_BLOCK_GROUP_RAID10;
1102 if ((flags & BTRFS_BLOCK_GROUP_DUP) &&
1103 (flags & (BTRFS_BLOCK_GROUP_RAID1 |
1104 BTRFS_BLOCK_GROUP_RAID10))) {
1105 flags &= ~BTRFS_BLOCK_GROUP_DUP;
1108 if ((flags & BTRFS_BLOCK_GROUP_RAID1) &&
1109 (flags & BTRFS_BLOCK_GROUP_RAID10)) {
1110 flags &= ~BTRFS_BLOCK_GROUP_RAID1;
1113 if ((flags & BTRFS_BLOCK_GROUP_RAID0) &&
1114 ((flags & BTRFS_BLOCK_GROUP_RAID1) |
1115 (flags & BTRFS_BLOCK_GROUP_RAID10) |
1116 (flags & BTRFS_BLOCK_GROUP_DUP)))
1117 flags &= ~BTRFS_BLOCK_GROUP_RAID0;
1121 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
1122 struct btrfs_root *extent_root, u64 alloc_bytes,
1125 struct btrfs_space_info *space_info;
1131 flags = reduce_alloc_profile(extent_root, flags);
1133 space_info = __find_space_info(extent_root->fs_info, flags);
1135 ret = update_space_info(extent_root->fs_info, flags,
1139 BUG_ON(!space_info);
1141 if (space_info->full)
1144 thresh = div_factor(space_info->total_bytes, 6);
1145 if ((space_info->bytes_used + space_info->bytes_pinned + alloc_bytes) <
1149 ret = btrfs_alloc_chunk(trans, extent_root, &start, &num_bytes, flags);
1150 if (ret == -ENOSPC) {
1151 printk("space info full %Lu\n", flags);
1152 space_info->full = 1;
1158 ret = btrfs_make_block_group(trans, extent_root, 0, flags,
1159 BTRFS_FIRST_CHUNK_TREE_OBJECTID, start, num_bytes);
1165 static int update_block_group(struct btrfs_trans_handle *trans,
1166 struct btrfs_root *root,
1167 u64 bytenr, u64 num_bytes, int alloc,
1170 struct btrfs_block_group_cache *cache;
1171 struct btrfs_fs_info *info = root->fs_info;
1172 u64 total = num_bytes;
1179 cache = btrfs_lookup_block_group(info, bytenr);
1183 byte_in_group = bytenr - cache->key.objectid;
1184 WARN_ON(byte_in_group > cache->key.offset);
1185 start = cache->key.objectid;
1186 end = start + cache->key.offset - 1;
1187 set_extent_bits(&info->block_group_cache, start, end,
1188 BLOCK_GROUP_DIRTY, GFP_NOFS);
1190 old_val = btrfs_block_group_used(&cache->item);
1191 num_bytes = min(total, cache->key.offset - byte_in_group);
1193 old_val += num_bytes;
1194 cache->space_info->bytes_used += num_bytes;
1196 old_val -= num_bytes;
1197 cache->space_info->bytes_used -= num_bytes;
1199 set_extent_dirty(&info->free_space_cache,
1200 bytenr, bytenr + num_bytes - 1,
1204 btrfs_set_block_group_used(&cache->item, old_val);
1206 bytenr += num_bytes;
1211 static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
1216 ret = find_first_extent_bit(&root->fs_info->block_group_cache,
1217 search_start, &start, &end,
1218 BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA |
1219 BLOCK_GROUP_SYSTEM);
1226 static int update_pinned_extents(struct btrfs_root *root,
1227 u64 bytenr, u64 num, int pin)
1230 struct btrfs_block_group_cache *cache;
1231 struct btrfs_fs_info *fs_info = root->fs_info;
1234 set_extent_dirty(&fs_info->pinned_extents,
1235 bytenr, bytenr + num - 1, GFP_NOFS);
1237 clear_extent_dirty(&fs_info->pinned_extents,
1238 bytenr, bytenr + num - 1, GFP_NOFS);
1241 cache = btrfs_lookup_block_group(fs_info, bytenr);
1243 u64 first = first_logical_byte(root, bytenr);
1244 WARN_ON(first < bytenr);
1245 len = min(first - bytenr, num);
1247 len = min(num, cache->key.offset -
1248 (bytenr - cache->key.objectid));
1252 cache->pinned += len;
1253 cache->space_info->bytes_pinned += len;
1255 fs_info->total_pinned += len;
1258 cache->pinned -= len;
1259 cache->space_info->bytes_pinned -= len;
1261 fs_info->total_pinned -= len;
1269 int btrfs_copy_pinned(struct btrfs_root *root, struct extent_io_tree *copy)
1274 struct extent_io_tree *pinned_extents = &root->fs_info->pinned_extents;
1278 ret = find_first_extent_bit(pinned_extents, last,
1279 &start, &end, EXTENT_DIRTY);
1282 set_extent_dirty(copy, start, end, GFP_NOFS);
1288 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
1289 struct btrfs_root *root,
1290 struct extent_io_tree *unpin)
1295 struct extent_io_tree *free_space_cache;
1296 free_space_cache = &root->fs_info->free_space_cache;
1299 ret = find_first_extent_bit(unpin, 0, &start, &end,
1303 update_pinned_extents(root, start, end + 1 - start, 0);
1304 clear_extent_dirty(unpin, start, end, GFP_NOFS);
1305 set_extent_dirty(free_space_cache, start, end, GFP_NOFS);
1310 static int finish_current_insert(struct btrfs_trans_handle *trans,
1311 struct btrfs_root *extent_root)
1315 struct btrfs_fs_info *info = extent_root->fs_info;
1316 struct extent_buffer *eb;
1317 struct btrfs_path *path;
1318 struct btrfs_key ins;
1319 struct btrfs_disk_key first;
1320 struct btrfs_extent_item extent_item;
1325 btrfs_set_stack_extent_refs(&extent_item, 1);
1326 btrfs_set_key_type(&ins, BTRFS_EXTENT_ITEM_KEY);
1327 path = btrfs_alloc_path();
1330 ret = find_first_extent_bit(&info->extent_ins, 0, &start,
1331 &end, EXTENT_LOCKED);
1335 ins.objectid = start;
1336 ins.offset = end + 1 - start;
1337 err = btrfs_insert_item(trans, extent_root, &ins,
1338 &extent_item, sizeof(extent_item));
1339 clear_extent_bits(&info->extent_ins, start, end, EXTENT_LOCKED,
1341 eb = read_tree_block(extent_root, ins.objectid, ins.offset,
1343 level = btrfs_header_level(eb);
1345 btrfs_item_key(eb, &first, 0);
1347 btrfs_node_key(eb, &first, 0);
1349 err = btrfs_insert_extent_backref(trans, extent_root, path,
1350 start, extent_root->root_key.objectid,
1352 btrfs_disk_key_objectid(&first));
1354 free_extent_buffer(eb);
1356 btrfs_free_path(path);
1360 static int pin_down_bytes(struct btrfs_root *root, u64 bytenr, u32 num_bytes,
1364 struct extent_buffer *buf;
1367 buf = btrfs_find_tree_block(root, bytenr, num_bytes);
1369 if (btrfs_buffer_uptodate(buf, 0)) {
1371 root->fs_info->running_transaction->transid;
1372 u64 header_transid =
1373 btrfs_header_generation(buf);
1374 if (header_transid == transid &&
1375 !btrfs_header_flag(buf,
1376 BTRFS_HEADER_FLAG_WRITTEN)) {
1377 clean_tree_block(NULL, root, buf);
1378 free_extent_buffer(buf);
1382 free_extent_buffer(buf);
1384 update_pinned_extents(root, bytenr, num_bytes, 1);
1386 set_extent_bits(&root->fs_info->pending_del,
1387 bytenr, bytenr + num_bytes - 1,
1388 EXTENT_LOCKED, GFP_NOFS);
1395 * remove an extent from the root, returns 0 on success
1397 static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
1398 *root, u64 bytenr, u64 num_bytes,
1399 u64 root_objectid, u64 ref_generation,
1400 u64 owner_objectid, u64 owner_offset, int pin,
1403 struct btrfs_path *path;
1404 struct btrfs_key key;
1405 struct btrfs_fs_info *info = root->fs_info;
1406 struct btrfs_root *extent_root = info->extent_root;
1407 struct extent_buffer *leaf;
1409 int extent_slot = 0;
1410 int found_extent = 0;
1412 struct btrfs_extent_item *ei;
1415 key.objectid = bytenr;
1416 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
1417 key.offset = num_bytes;
1418 path = btrfs_alloc_path();
1423 ret = lookup_extent_backref(trans, extent_root, path,
1424 bytenr, root_objectid,
1426 owner_objectid, owner_offset, 1);
1428 struct btrfs_key found_key;
1429 extent_slot = path->slots[0];
1430 while(extent_slot > 0) {
1432 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1434 if (found_key.objectid != bytenr)
1436 if (found_key.type == BTRFS_EXTENT_ITEM_KEY &&
1437 found_key.offset == num_bytes) {
1441 if (path->slots[0] - extent_slot > 5)
1445 ret = btrfs_del_item(trans, extent_root, path);
1447 btrfs_print_leaf(extent_root, path->nodes[0]);
1449 printk("Unable to find ref byte nr %Lu root %Lu "
1450 " gen %Lu owner %Lu offset %Lu\n", bytenr,
1451 root_objectid, ref_generation, owner_objectid,
1454 if (!found_extent) {
1455 btrfs_release_path(extent_root, path);
1456 ret = btrfs_search_slot(trans, extent_root, &key, path, -1, 1);
1460 extent_slot = path->slots[0];
1463 leaf = path->nodes[0];
1464 ei = btrfs_item_ptr(leaf, extent_slot,
1465 struct btrfs_extent_item);
1466 refs = btrfs_extent_refs(leaf, ei);
1469 btrfs_set_extent_refs(leaf, ei, refs);
1471 btrfs_mark_buffer_dirty(leaf);
1473 if (refs == 0 && found_extent && path->slots[0] == extent_slot + 1) {
1474 /* if the back ref and the extent are next to each other
1475 * they get deleted below in one shot
1477 path->slots[0] = extent_slot;
1479 } else if (found_extent) {
1480 /* otherwise delete the extent back ref */
1481 ret = btrfs_del_item(trans, extent_root, path);
1483 /* if refs are 0, we need to setup the path for deletion */
1485 btrfs_release_path(extent_root, path);
1486 ret = btrfs_search_slot(trans, extent_root, &key, path,
1499 ret = pin_down_bytes(root, bytenr, num_bytes, 0);
1505 /* block accounting for super block */
1506 super_used = btrfs_super_bytes_used(&info->super_copy);
1507 btrfs_set_super_bytes_used(&info->super_copy,
1508 super_used - num_bytes);
1510 /* block accounting for root item */
1511 root_used = btrfs_root_used(&root->root_item);
1512 btrfs_set_root_used(&root->root_item,
1513 root_used - num_bytes);
1514 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
1519 ret = update_block_group(trans, root, bytenr, num_bytes, 0,
1523 btrfs_free_path(path);
1524 finish_current_insert(trans, extent_root);
1529 * find all the blocks marked as pending in the radix tree and remove
1530 * them from the extent map
1532 static int del_pending_extents(struct btrfs_trans_handle *trans, struct
1533 btrfs_root *extent_root)
1539 struct extent_io_tree *pending_del;
1540 struct extent_io_tree *pinned_extents;
1542 pending_del = &extent_root->fs_info->pending_del;
1543 pinned_extents = &extent_root->fs_info->pinned_extents;
1546 ret = find_first_extent_bit(pending_del, 0, &start, &end,
1550 update_pinned_extents(extent_root, start, end + 1 - start, 1);
1551 clear_extent_bits(pending_del, start, end, EXTENT_LOCKED,
1553 ret = __free_extent(trans, extent_root,
1554 start, end + 1 - start,
1555 extent_root->root_key.objectid,
1564 * remove an extent from the root, returns 0 on success
1566 int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
1567 *root, u64 bytenr, u64 num_bytes,
1568 u64 root_objectid, u64 ref_generation,
1569 u64 owner_objectid, u64 owner_offset, int pin)
1571 struct btrfs_root *extent_root = root->fs_info->extent_root;
1575 WARN_ON(num_bytes < root->sectorsize);
1576 if (!root->ref_cows)
1579 if (root == extent_root) {
1580 pin_down_bytes(root, bytenr, num_bytes, 1);
1583 ret = __free_extent(trans, root, bytenr, num_bytes, root_objectid,
1584 ref_generation, owner_objectid, owner_offset,
1586 pending_ret = del_pending_extents(trans, root->fs_info->extent_root);
1587 return ret ? ret : pending_ret;
1590 static u64 stripe_align(struct btrfs_root *root, u64 val)
1592 u64 mask = ((u64)root->stripesize - 1);
1593 u64 ret = (val + mask) & ~mask;
1598 * walks the btree of allocated extents and find a hole of a given size.
1599 * The key ins is changed to record the hole:
1600 * ins->objectid == block start
1601 * ins->flags = BTRFS_EXTENT_ITEM_KEY
1602 * ins->offset == number of blocks
1603 * Any available blocks before search_start are skipped.
1605 static int noinline find_free_extent(struct btrfs_trans_handle *trans,
1606 struct btrfs_root *orig_root,
1607 u64 num_bytes, u64 empty_size,
1608 u64 search_start, u64 search_end,
1609 u64 hint_byte, struct btrfs_key *ins,
1610 u64 exclude_start, u64 exclude_nr,
1614 u64 orig_search_start;
1615 struct btrfs_root * root = orig_root->fs_info->extent_root;
1616 struct btrfs_fs_info *info = root->fs_info;
1617 u64 total_needed = num_bytes;
1618 u64 *last_ptr = NULL;
1619 struct btrfs_block_group_cache *block_group;
1622 int empty_cluster = 2 * 1024 * 1024;
1624 WARN_ON(num_bytes < root->sectorsize);
1625 btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
1627 if (data & BTRFS_BLOCK_GROUP_METADATA) {
1628 last_ptr = &root->fs_info->last_alloc;
1629 empty_cluster = 256 * 1024;
1632 if ((data & BTRFS_BLOCK_GROUP_DATA) && btrfs_test_opt(root, SSD)) {
1633 last_ptr = &root->fs_info->last_data_alloc;
1638 hint_byte = *last_ptr;
1640 empty_size += empty_cluster;
1644 search_start = max(search_start, first_logical_byte(root, 0));
1645 orig_search_start = search_start;
1647 if (search_end == (u64)-1)
1648 search_end = btrfs_super_total_bytes(&info->super_copy);
1651 block_group = btrfs_lookup_block_group(info, hint_byte);
1653 hint_byte = search_start;
1654 block_group = btrfs_find_block_group(root, block_group,
1655 hint_byte, data, 1);
1656 if (last_ptr && *last_ptr == 0 && block_group)
1657 hint_byte = block_group->key.objectid;
1659 block_group = btrfs_find_block_group(root,
1661 search_start, data, 1);
1663 search_start = max(search_start, hint_byte);
1665 total_needed += empty_size;
1669 block_group = btrfs_lookup_block_group(info, search_start);
1671 block_group = btrfs_lookup_block_group(info,
1674 ret = find_search_start(root, &block_group, &search_start,
1675 total_needed, data);
1676 if (ret == -ENOSPC && last_ptr && *last_ptr) {
1678 block_group = btrfs_lookup_block_group(info,
1680 search_start = orig_search_start;
1681 ret = find_search_start(root, &block_group, &search_start,
1682 total_needed, data);
1689 if (last_ptr && *last_ptr && search_start != *last_ptr) {
1692 empty_size += empty_cluster;
1693 total_needed += empty_size;
1695 block_group = btrfs_lookup_block_group(info,
1697 search_start = orig_search_start;
1698 ret = find_search_start(root, &block_group,
1699 &search_start, total_needed, data);
1706 search_start = stripe_align(root, search_start);
1707 ins->objectid = search_start;
1708 ins->offset = num_bytes;
1710 if (ins->objectid + num_bytes >= search_end)
1713 if (ins->objectid + num_bytes >
1714 block_group->key.objectid + block_group->key.offset) {
1715 search_start = block_group->key.objectid +
1716 block_group->key.offset;
1720 if (test_range_bit(&info->extent_ins, ins->objectid,
1721 ins->objectid + num_bytes -1, EXTENT_LOCKED, 0)) {
1722 search_start = ins->objectid + num_bytes;
1726 if (test_range_bit(&info->pinned_extents, ins->objectid,
1727 ins->objectid + num_bytes -1, EXTENT_DIRTY, 0)) {
1728 search_start = ins->objectid + num_bytes;
1732 if (exclude_nr > 0 && (ins->objectid + num_bytes > exclude_start &&
1733 ins->objectid < exclude_start + exclude_nr)) {
1734 search_start = exclude_start + exclude_nr;
1738 if (!(data & BTRFS_BLOCK_GROUP_DATA)) {
1739 block_group = btrfs_lookup_block_group(info, ins->objectid);
1741 trans->block_group = block_group;
1743 ins->offset = num_bytes;
1745 *last_ptr = ins->objectid + ins->offset;
1747 btrfs_super_total_bytes(&root->fs_info->super_copy)) {
1754 if (search_start + num_bytes >= search_end) {
1756 search_start = orig_search_start;
1763 total_needed -= empty_size;
1768 block_group = btrfs_lookup_block_group(info, search_start);
1770 block_group = btrfs_find_block_group(root, block_group,
1771 search_start, data, 0);
1779 * finds a free extent and does all the dirty work required for allocation
1780 * returns the key for the extent through ins, and a tree buffer for
1781 * the first block of the extent through buf.
1783 * returns 0 if everything worked, non-zero otherwise.
1785 int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
1786 struct btrfs_root *root,
1787 u64 num_bytes, u64 min_alloc_size,
1788 u64 root_objectid, u64 ref_generation,
1789 u64 owner, u64 owner_offset,
1790 u64 empty_size, u64 hint_byte,
1791 u64 search_end, struct btrfs_key *ins, u64 data)
1797 u64 search_start = 0;
1800 struct btrfs_fs_info *info = root->fs_info;
1801 struct btrfs_root *extent_root = info->extent_root;
1802 struct btrfs_extent_item *extent_item;
1803 struct btrfs_extent_ref *ref;
1804 struct btrfs_path *path;
1805 struct btrfs_key keys[2];
1808 alloc_profile = info->avail_data_alloc_bits &
1809 info->data_alloc_profile;
1810 data = BTRFS_BLOCK_GROUP_DATA | alloc_profile;
1811 } else if (root == root->fs_info->chunk_root) {
1812 alloc_profile = info->avail_system_alloc_bits &
1813 info->system_alloc_profile;
1814 data = BTRFS_BLOCK_GROUP_SYSTEM | alloc_profile;
1816 alloc_profile = info->avail_metadata_alloc_bits &
1817 info->metadata_alloc_profile;
1818 data = BTRFS_BLOCK_GROUP_METADATA | alloc_profile;
1821 data = reduce_alloc_profile(root, data);
1822 if (root->ref_cows) {
1823 if (!(data & BTRFS_BLOCK_GROUP_METADATA)) {
1824 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
1826 BTRFS_BLOCK_GROUP_METADATA |
1827 (info->metadata_alloc_profile &
1828 info->avail_metadata_alloc_bits));
1831 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
1832 num_bytes + 2 * 1024 * 1024, data);
1836 WARN_ON(num_bytes < root->sectorsize);
1837 ret = find_free_extent(trans, root, num_bytes, empty_size,
1838 search_start, search_end, hint_byte, ins,
1839 trans->alloc_exclude_start,
1840 trans->alloc_exclude_nr, data);
1842 if (ret == -ENOSPC && num_bytes > min_alloc_size) {
1843 num_bytes = num_bytes >> 1;
1844 num_bytes = max(num_bytes, min_alloc_size);
1848 printk("allocation failed flags %Lu\n", data);
1854 /* block accounting for super block */
1855 super_used = btrfs_super_bytes_used(&info->super_copy);
1856 btrfs_set_super_bytes_used(&info->super_copy, super_used + num_bytes);
1858 /* block accounting for root item */
1859 root_used = btrfs_root_used(&root->root_item);
1860 btrfs_set_root_used(&root->root_item, root_used + num_bytes);
1862 clear_extent_dirty(&root->fs_info->free_space_cache,
1863 ins->objectid, ins->objectid + ins->offset - 1,
1866 if (root == extent_root) {
1867 set_extent_bits(&root->fs_info->extent_ins, ins->objectid,
1868 ins->objectid + ins->offset - 1,
1869 EXTENT_LOCKED, GFP_NOFS);
1873 WARN_ON(trans->alloc_exclude_nr);
1874 trans->alloc_exclude_start = ins->objectid;
1875 trans->alloc_exclude_nr = ins->offset;
1877 memcpy(&keys[0], ins, sizeof(*ins));
1878 keys[1].offset = hash_extent_ref(root_objectid, ref_generation,
1879 owner, owner_offset);
1880 keys[1].objectid = ins->objectid;
1881 keys[1].type = BTRFS_EXTENT_REF_KEY;
1882 sizes[0] = sizeof(*extent_item);
1883 sizes[1] = sizeof(*ref);
1885 path = btrfs_alloc_path();
1888 ret = btrfs_insert_empty_items(trans, extent_root, path, keys,
1892 extent_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
1893 struct btrfs_extent_item);
1894 btrfs_set_extent_refs(path->nodes[0], extent_item, 1);
1895 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
1896 struct btrfs_extent_ref);
1898 btrfs_set_ref_root(path->nodes[0], ref, root_objectid);
1899 btrfs_set_ref_generation(path->nodes[0], ref, ref_generation);
1900 btrfs_set_ref_objectid(path->nodes[0], ref, owner);
1901 btrfs_set_ref_offset(path->nodes[0], ref, owner_offset);
1903 btrfs_mark_buffer_dirty(path->nodes[0]);
1905 trans->alloc_exclude_start = 0;
1906 trans->alloc_exclude_nr = 0;
1907 btrfs_free_path(path);
1908 finish_current_insert(trans, extent_root);
1909 pending_ret = del_pending_extents(trans, extent_root);
1919 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1, 0);
1921 printk("update block group failed for %Lu %Lu\n",
1922 ins->objectid, ins->offset);
1929 * helper function to allocate a block for a given tree
1930 * returns the tree buffer or NULL.
1932 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
1933 struct btrfs_root *root,
1935 u64 root_objectid, u64 hint,
1941 ref_generation = trans->transid;
1946 return __btrfs_alloc_free_block(trans, root, blocksize, root_objectid,
1947 ref_generation, 0, 0, hint, empty_size);
1951 * helper function to allocate a block for a given tree
1952 * returns the tree buffer or NULL.
1954 struct extent_buffer *__btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
1955 struct btrfs_root *root,
1964 struct btrfs_key ins;
1966 struct extent_buffer *buf;
1968 ret = btrfs_alloc_extent(trans, root, blocksize, blocksize,
1969 root_objectid, ref_generation,
1970 level, first_objectid, empty_size, hint,
1974 return ERR_PTR(ret);
1976 buf = btrfs_find_create_tree_block(root, ins.objectid, blocksize);
1978 btrfs_free_extent(trans, root, ins.objectid, blocksize,
1979 root->root_key.objectid, ref_generation,
1981 return ERR_PTR(-ENOMEM);
1983 btrfs_set_header_generation(buf, trans->transid);
1984 clean_tree_block(trans, root, buf);
1985 btrfs_set_buffer_uptodate(buf);
1987 if (PageDirty(buf->first_page)) {
1988 printk("page %lu dirty\n", buf->first_page->index);
1992 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
1993 buf->start + buf->len - 1, GFP_NOFS);
1994 if (!btrfs_test_opt(root, SSD))
1995 btrfs_set_buffer_defrag(buf);
1996 trans->blocks_used++;
2000 static int noinline drop_leaf_ref(struct btrfs_trans_handle *trans,
2001 struct btrfs_root *root,
2002 struct extent_buffer *leaf)
2005 u64 leaf_generation;
2006 struct btrfs_key key;
2007 struct btrfs_file_extent_item *fi;
2012 BUG_ON(!btrfs_is_leaf(leaf));
2013 nritems = btrfs_header_nritems(leaf);
2014 leaf_owner = btrfs_header_owner(leaf);
2015 leaf_generation = btrfs_header_generation(leaf);
2017 for (i = 0; i < nritems; i++) {
2020 btrfs_item_key_to_cpu(leaf, &key, i);
2021 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2023 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
2024 if (btrfs_file_extent_type(leaf, fi) ==
2025 BTRFS_FILE_EXTENT_INLINE)
2028 * FIXME make sure to insert a trans record that
2029 * repeats the snapshot del on crash
2031 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
2032 if (disk_bytenr == 0)
2034 ret = btrfs_free_extent(trans, root, disk_bytenr,
2035 btrfs_file_extent_disk_num_bytes(leaf, fi),
2036 leaf_owner, leaf_generation,
2037 key.objectid, key.offset, 0);
2043 static void noinline reada_walk_down(struct btrfs_root *root,
2044 struct extent_buffer *node,
2057 nritems = btrfs_header_nritems(node);
2058 level = btrfs_header_level(node);
2062 for (i = slot; i < nritems && skipped < 32; i++) {
2063 bytenr = btrfs_node_blockptr(node, i);
2064 if (last && ((bytenr > last && bytenr - last > 32 * 1024) ||
2065 (last > bytenr && last - bytenr > 32 * 1024))) {
2069 blocksize = btrfs_level_size(root, level - 1);
2071 ret = lookup_extent_ref(NULL, root, bytenr,
2079 mutex_unlock(&root->fs_info->fs_mutex);
2080 ret = readahead_tree_block(root, bytenr, blocksize,
2081 btrfs_node_ptr_generation(node, i));
2082 last = bytenr + blocksize;
2084 mutex_lock(&root->fs_info->fs_mutex);
2091 * helper function for drop_snapshot, this walks down the tree dropping ref
2092 * counts as it goes.
2094 static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
2095 struct btrfs_root *root,
2096 struct btrfs_path *path, int *level)
2102 struct extent_buffer *next;
2103 struct extent_buffer *cur;
2104 struct extent_buffer *parent;
2109 WARN_ON(*level < 0);
2110 WARN_ON(*level >= BTRFS_MAX_LEVEL);
2111 ret = lookup_extent_ref(trans, root,
2112 path->nodes[*level]->start,
2113 path->nodes[*level]->len, &refs);
2119 * walk down to the last node level and free all the leaves
2121 while(*level >= 0) {
2122 WARN_ON(*level < 0);
2123 WARN_ON(*level >= BTRFS_MAX_LEVEL);
2124 cur = path->nodes[*level];
2126 if (btrfs_header_level(cur) != *level)
2129 if (path->slots[*level] >=
2130 btrfs_header_nritems(cur))
2133 ret = drop_leaf_ref(trans, root, cur);
2137 bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
2138 ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
2139 blocksize = btrfs_level_size(root, *level - 1);
2140 ret = lookup_extent_ref(trans, root, bytenr, blocksize, &refs);
2143 parent = path->nodes[*level];
2144 root_owner = btrfs_header_owner(parent);
2145 root_gen = btrfs_header_generation(parent);
2146 path->slots[*level]++;
2147 ret = btrfs_free_extent(trans, root, bytenr,
2148 blocksize, root_owner,
2153 next = btrfs_find_tree_block(root, bytenr, blocksize);
2154 if (!next || !btrfs_buffer_uptodate(next, ptr_gen)) {
2155 free_extent_buffer(next);
2156 reada_walk_down(root, cur, path->slots[*level]);
2158 mutex_unlock(&root->fs_info->fs_mutex);
2159 next = read_tree_block(root, bytenr, blocksize,
2161 mutex_lock(&root->fs_info->fs_mutex);
2163 /* we've dropped the lock, double check */
2164 ret = lookup_extent_ref(trans, root, bytenr,
2168 parent = path->nodes[*level];
2169 root_owner = btrfs_header_owner(parent);
2170 root_gen = btrfs_header_generation(parent);
2172 path->slots[*level]++;
2173 free_extent_buffer(next);
2174 ret = btrfs_free_extent(trans, root, bytenr,
2182 WARN_ON(*level <= 0);
2183 if (path->nodes[*level-1])
2184 free_extent_buffer(path->nodes[*level-1]);
2185 path->nodes[*level-1] = next;
2186 *level = btrfs_header_level(next);
2187 path->slots[*level] = 0;
2190 WARN_ON(*level < 0);
2191 WARN_ON(*level >= BTRFS_MAX_LEVEL);
2193 if (path->nodes[*level] == root->node) {
2194 root_owner = root->root_key.objectid;
2195 parent = path->nodes[*level];
2197 parent = path->nodes[*level + 1];
2198 root_owner = btrfs_header_owner(parent);
2201 root_gen = btrfs_header_generation(parent);
2202 ret = btrfs_free_extent(trans, root, path->nodes[*level]->start,
2203 path->nodes[*level]->len,
2204 root_owner, root_gen, 0, 0, 1);
2205 free_extent_buffer(path->nodes[*level]);
2206 path->nodes[*level] = NULL;
2213 * helper for dropping snapshots. This walks back up the tree in the path
2214 * to find the first node higher up where we haven't yet gone through
2217 static int noinline walk_up_tree(struct btrfs_trans_handle *trans,
2218 struct btrfs_root *root,
2219 struct btrfs_path *path, int *level)
2223 struct btrfs_root_item *root_item = &root->root_item;
2228 for(i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
2229 slot = path->slots[i];
2230 if (slot < btrfs_header_nritems(path->nodes[i]) - 1) {
2231 struct extent_buffer *node;
2232 struct btrfs_disk_key disk_key;
2233 node = path->nodes[i];
2236 WARN_ON(*level == 0);
2237 btrfs_node_key(node, &disk_key, path->slots[i]);
2238 memcpy(&root_item->drop_progress,
2239 &disk_key, sizeof(disk_key));
2240 root_item->drop_level = i;
2243 if (path->nodes[*level] == root->node) {
2244 root_owner = root->root_key.objectid;
2246 btrfs_header_generation(path->nodes[*level]);
2248 struct extent_buffer *node;
2249 node = path->nodes[*level + 1];
2250 root_owner = btrfs_header_owner(node);
2251 root_gen = btrfs_header_generation(node);
2253 ret = btrfs_free_extent(trans, root,
2254 path->nodes[*level]->start,
2255 path->nodes[*level]->len,
2256 root_owner, root_gen, 0, 0, 1);
2258 free_extent_buffer(path->nodes[*level]);
2259 path->nodes[*level] = NULL;
2267 * drop the reference count on the tree rooted at 'snap'. This traverses
2268 * the tree freeing any blocks that have a ref count of zero after being
2271 int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root
2277 struct btrfs_path *path;
2280 struct btrfs_root_item *root_item = &root->root_item;
2282 path = btrfs_alloc_path();
2285 level = btrfs_header_level(root->node);
2287 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
2288 path->nodes[level] = root->node;
2289 extent_buffer_get(root->node);
2290 path->slots[level] = 0;
2292 struct btrfs_key key;
2293 struct btrfs_disk_key found_key;
2294 struct extent_buffer *node;
2296 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
2297 level = root_item->drop_level;
2298 path->lowest_level = level;
2299 wret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2304 node = path->nodes[level];
2305 btrfs_node_key(node, &found_key, path->slots[level]);
2306 WARN_ON(memcmp(&found_key, &root_item->drop_progress,
2307 sizeof(found_key)));
2310 wret = walk_down_tree(trans, root, path, &level);
2316 wret = walk_up_tree(trans, root, path, &level);
2324 for (i = 0; i <= orig_level; i++) {
2325 if (path->nodes[i]) {
2326 free_extent_buffer(path->nodes[i]);
2327 path->nodes[i] = NULL;
2331 btrfs_free_path(path);
2335 int btrfs_free_block_groups(struct btrfs_fs_info *info)
2342 ret = find_first_extent_bit(&info->block_group_cache, 0,
2343 &start, &end, (unsigned int)-1);
2346 ret = get_state_private(&info->block_group_cache, start, &ptr);
2348 kfree((void *)(unsigned long)ptr);
2349 clear_extent_bits(&info->block_group_cache, start,
2350 end, (unsigned int)-1, GFP_NOFS);
2353 ret = find_first_extent_bit(&info->free_space_cache, 0,
2354 &start, &end, EXTENT_DIRTY);
2357 clear_extent_dirty(&info->free_space_cache, start,
2363 static unsigned long calc_ra(unsigned long start, unsigned long last,
2366 return min(last, start + nr - 1);
2369 static int noinline relocate_inode_pages(struct inode *inode, u64 start,
2374 unsigned long last_index;
2377 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2378 struct file_ra_state *ra;
2379 unsigned long total_read = 0;
2380 unsigned long ra_pages;
2381 struct btrfs_trans_handle *trans;
2383 ra = kzalloc(sizeof(*ra), GFP_NOFS);
2385 mutex_lock(&inode->i_mutex);
2386 i = start >> PAGE_CACHE_SHIFT;
2387 last_index = (start + len - 1) >> PAGE_CACHE_SHIFT;
2389 ra_pages = BTRFS_I(inode)->root->fs_info->bdi.ra_pages;
2391 file_ra_state_init(ra, inode->i_mapping);
2393 for (; i <= last_index; i++) {
2394 if (total_read % ra_pages == 0) {
2395 btrfs_force_ra(inode->i_mapping, ra, NULL, i,
2396 calc_ra(i, last_index, ra_pages));
2399 if (((u64)i << PAGE_CACHE_SHIFT) > inode->i_size)
2400 goto truncate_racing;
2402 page = grab_cache_page(inode->i_mapping, i);
2406 if (!PageUptodate(page)) {
2407 btrfs_readpage(NULL, page);
2409 if (!PageUptodate(page)) {
2411 page_cache_release(page);
2415 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
2416 ClearPageDirty(page);
2418 cancel_dirty_page(page, PAGE_CACHE_SIZE);
2420 wait_on_page_writeback(page);
2421 set_page_extent_mapped(page);
2422 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
2423 page_end = page_start + PAGE_CACHE_SIZE - 1;
2425 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
2427 set_extent_delalloc(io_tree, page_start,
2428 page_end, GFP_NOFS);
2429 set_page_dirty(page);
2431 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
2433 page_cache_release(page);
2435 balance_dirty_pages_ratelimited_nr(inode->i_mapping,
2440 trans = btrfs_start_transaction(BTRFS_I(inode)->root, 1);
2442 btrfs_add_ordered_inode(inode);
2443 btrfs_end_transaction(trans, BTRFS_I(inode)->root);
2444 mark_inode_dirty(inode);
2446 mutex_unlock(&inode->i_mutex);
2450 vmtruncate(inode, inode->i_size);
2451 balance_dirty_pages_ratelimited_nr(inode->i_mapping,
2457 * The back references tell us which tree holds a ref on a block,
2458 * but it is possible for the tree root field in the reference to
2459 * reflect the original root before a snapshot was made. In this
2460 * case we should search through all the children of a given root
2461 * to find potential holders of references on a block.
2463 * Instead, we do something a little less fancy and just search
2464 * all the roots for a given key/block combination.
2466 static int find_root_for_ref(struct btrfs_root *root,
2467 struct btrfs_path *path,
2468 struct btrfs_key *key0,
2471 struct btrfs_root **found_root,
2474 struct btrfs_key root_location;
2475 struct btrfs_root *cur_root = *found_root;
2476 struct btrfs_file_extent_item *file_extent;
2477 u64 root_search_start = BTRFS_FS_TREE_OBJECTID;
2482 root_location.offset = (u64)-1;
2483 root_location.type = BTRFS_ROOT_ITEM_KEY;
2484 path->lowest_level = level;
2487 ret = btrfs_search_slot(NULL, cur_root, key0, path, 0, 0);
2489 if (ret == 0 && file_key) {
2490 struct extent_buffer *leaf = path->nodes[0];
2491 file_extent = btrfs_item_ptr(leaf, path->slots[0],
2492 struct btrfs_file_extent_item);
2493 if (btrfs_file_extent_type(leaf, file_extent) ==
2494 BTRFS_FILE_EXTENT_REG) {
2496 btrfs_file_extent_disk_bytenr(leaf,
2499 } else if (!file_key) {
2500 if (path->nodes[level])
2501 found_bytenr = path->nodes[level]->start;
2504 for (i = level; i < BTRFS_MAX_LEVEL; i++) {
2505 if (!path->nodes[i])
2507 free_extent_buffer(path->nodes[i]);
2508 path->nodes[i] = NULL;
2510 btrfs_release_path(cur_root, path);
2512 if (found_bytenr == bytenr) {
2513 *found_root = cur_root;
2517 ret = btrfs_search_root(root->fs_info->tree_root,
2518 root_search_start, &root_search_start);
2522 root_location.objectid = root_search_start;
2523 cur_root = btrfs_read_fs_root_no_name(root->fs_info,
2531 path->lowest_level = 0;
2536 * note, this releases the path
2538 static int noinline relocate_one_reference(struct btrfs_root *extent_root,
2539 struct btrfs_path *path,
2540 struct btrfs_key *extent_key)
2542 struct inode *inode;
2543 struct btrfs_root *found_root;
2544 struct btrfs_key root_location;
2545 struct btrfs_key found_key;
2546 struct btrfs_extent_ref *ref;
2554 ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
2555 struct btrfs_extent_ref);
2556 ref_root = btrfs_ref_root(path->nodes[0], ref);
2557 ref_gen = btrfs_ref_generation(path->nodes[0], ref);
2558 ref_objectid = btrfs_ref_objectid(path->nodes[0], ref);
2559 ref_offset = btrfs_ref_offset(path->nodes[0], ref);
2560 btrfs_release_path(extent_root, path);
2562 root_location.objectid = ref_root;
2564 root_location.offset = 0;
2566 root_location.offset = (u64)-1;
2567 root_location.type = BTRFS_ROOT_ITEM_KEY;
2569 found_root = btrfs_read_fs_root_no_name(extent_root->fs_info,
2571 BUG_ON(!found_root);
2573 if (ref_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
2574 found_key.objectid = ref_objectid;
2575 found_key.type = BTRFS_EXTENT_DATA_KEY;
2576 found_key.offset = ref_offset;
2579 ret = find_root_for_ref(extent_root, path, &found_key,
2580 level, 1, &found_root,
2581 extent_key->objectid);
2586 mutex_unlock(&extent_root->fs_info->fs_mutex);
2587 inode = btrfs_iget_locked(extent_root->fs_info->sb,
2588 ref_objectid, found_root);
2589 if (inode->i_state & I_NEW) {
2590 /* the inode and parent dir are two different roots */
2591 BTRFS_I(inode)->root = found_root;
2592 BTRFS_I(inode)->location.objectid = ref_objectid;
2593 BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY;
2594 BTRFS_I(inode)->location.offset = 0;
2595 btrfs_read_locked_inode(inode);
2596 unlock_new_inode(inode);
2599 /* this can happen if the reference is not against
2600 * the latest version of the tree root
2602 if (is_bad_inode(inode)) {
2603 mutex_lock(&extent_root->fs_info->fs_mutex);
2606 relocate_inode_pages(inode, ref_offset, extent_key->offset);
2608 mutex_lock(&extent_root->fs_info->fs_mutex);
2610 struct btrfs_trans_handle *trans;
2611 struct extent_buffer *eb;
2614 eb = read_tree_block(found_root, extent_key->objectid,
2615 extent_key->offset, 0);
2616 level = btrfs_header_level(eb);
2619 btrfs_item_key_to_cpu(eb, &found_key, 0);
2621 btrfs_node_key_to_cpu(eb, &found_key, 0);
2623 free_extent_buffer(eb);
2625 ret = find_root_for_ref(extent_root, path, &found_key,
2626 level, 0, &found_root,
2627 extent_key->objectid);
2632 trans = btrfs_start_transaction(found_root, 1);
2634 path->lowest_level = level;
2636 ret = btrfs_search_slot(trans, found_root, &found_key, path,
2638 path->lowest_level = 0;
2639 for (i = level; i < BTRFS_MAX_LEVEL; i++) {
2640 if (!path->nodes[i])
2642 free_extent_buffer(path->nodes[i]);
2643 path->nodes[i] = NULL;
2645 btrfs_release_path(found_root, path);
2646 btrfs_end_transaction(trans, found_root);
2653 static int noinline del_extent_zero(struct btrfs_root *extent_root,
2654 struct btrfs_path *path,
2655 struct btrfs_key *extent_key)
2658 struct btrfs_trans_handle *trans;
2660 trans = btrfs_start_transaction(extent_root, 1);
2661 ret = btrfs_search_slot(trans, extent_root, extent_key, path, -1, 1);
2668 ret = btrfs_del_item(trans, extent_root, path);
2670 btrfs_end_transaction(trans, extent_root);
2674 static int noinline relocate_one_extent(struct btrfs_root *extent_root,
2675 struct btrfs_path *path,
2676 struct btrfs_key *extent_key)
2678 struct btrfs_key key;
2679 struct btrfs_key found_key;
2680 struct extent_buffer *leaf;
2685 if (extent_key->objectid == 0) {
2686 ret = del_extent_zero(extent_root, path, extent_key);
2689 key.objectid = extent_key->objectid;
2690 key.type = BTRFS_EXTENT_REF_KEY;
2694 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
2700 leaf = path->nodes[0];
2701 nritems = btrfs_header_nritems(leaf);
2702 if (path->slots[0] == nritems) {
2703 ret = btrfs_next_leaf(extent_root, path);
2710 leaf = path->nodes[0];
2713 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2714 if (found_key.objectid != extent_key->objectid) {
2718 if (found_key.type != BTRFS_EXTENT_REF_KEY) {
2722 key.offset = found_key.offset + 1;
2723 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2725 ret = relocate_one_reference(extent_root, path, extent_key);
2731 btrfs_release_path(extent_root, path);
2735 static u64 update_block_group_flags(struct btrfs_root *root, u64 flags)
2738 u64 stripped = BTRFS_BLOCK_GROUP_RAID0 |
2739 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
2741 num_devices = root->fs_info->fs_devices->num_devices;
2742 if (num_devices == 1) {
2743 stripped |= BTRFS_BLOCK_GROUP_DUP;
2744 stripped = flags & ~stripped;
2746 /* turn raid0 into single device chunks */
2747 if (flags & BTRFS_BLOCK_GROUP_RAID0)
2750 /* turn mirroring into duplication */
2751 if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
2752 BTRFS_BLOCK_GROUP_RAID10))
2753 return stripped | BTRFS_BLOCK_GROUP_DUP;
2756 /* they already had raid on here, just return */
2757 if (flags & stripped)
2760 stripped |= BTRFS_BLOCK_GROUP_DUP;
2761 stripped = flags & ~stripped;
2763 /* switch duplicated blocks with raid1 */
2764 if (flags & BTRFS_BLOCK_GROUP_DUP)
2765 return stripped | BTRFS_BLOCK_GROUP_RAID1;
2767 /* turn single device chunks into raid0 */
2768 return stripped | BTRFS_BLOCK_GROUP_RAID0;
2773 int btrfs_shrink_extent_tree(struct btrfs_root *root, u64 shrink_start)
2775 struct btrfs_trans_handle *trans;
2776 struct btrfs_root *tree_root = root->fs_info->tree_root;
2777 struct btrfs_path *path;
2780 u64 shrink_last_byte;
2781 u64 new_alloc_flags;
2782 struct btrfs_block_group_cache *shrink_block_group;
2783 struct btrfs_fs_info *info = root->fs_info;
2784 struct btrfs_key key;
2785 struct btrfs_key found_key;
2786 struct extent_buffer *leaf;
2791 shrink_block_group = btrfs_lookup_block_group(root->fs_info,
2793 BUG_ON(!shrink_block_group);
2795 shrink_last_byte = shrink_start + shrink_block_group->key.offset;
2797 shrink_block_group->space_info->total_bytes -=
2798 shrink_block_group->key.offset;
2799 path = btrfs_alloc_path();
2800 root = root->fs_info->extent_root;
2803 printk("btrfs relocating block group %llu flags %llu\n",
2804 (unsigned long long)shrink_start,
2805 (unsigned long long)shrink_block_group->flags);
2808 if (btrfs_block_group_used(&shrink_block_group->item) > 0) {
2811 trans = btrfs_start_transaction(root, 1);
2812 new_alloc_flags = update_block_group_flags(root,
2813 shrink_block_group->flags);
2814 if (new_alloc_flags != shrink_block_group->flags) {
2816 btrfs_block_group_used(&shrink_block_group->item);
2818 calc = shrink_block_group->key.offset;
2820 do_chunk_alloc(trans, root->fs_info->extent_root,
2821 calc + 2 * 1024 * 1024, new_alloc_flags);
2822 btrfs_end_transaction(trans, root);
2824 shrink_block_group->ro = 1;
2828 key.objectid = shrink_start;
2831 cur_byte = key.objectid;
2833 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2837 ret = btrfs_previous_item(root, path, 0, BTRFS_EXTENT_ITEM_KEY);
2842 leaf = path->nodes[0];
2843 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2844 if (found_key.objectid + found_key.offset > shrink_start &&
2845 found_key.objectid < shrink_last_byte) {
2846 cur_byte = found_key.objectid;
2847 key.objectid = cur_byte;
2850 btrfs_release_path(root, path);
2853 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2857 leaf = path->nodes[0];
2858 nritems = btrfs_header_nritems(leaf);
2860 if (path->slots[0] >= nritems) {
2861 ret = btrfs_next_leaf(root, path);
2868 leaf = path->nodes[0];
2869 nritems = btrfs_header_nritems(leaf);
2872 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2874 if (found_key.objectid >= shrink_last_byte)
2877 if (progress && need_resched()) {
2878 memcpy(&key, &found_key, sizeof(key));
2879 mutex_unlock(&root->fs_info->fs_mutex);
2881 mutex_lock(&root->fs_info->fs_mutex);
2882 btrfs_release_path(root, path);
2883 btrfs_search_slot(NULL, root, &key, path, 0, 0);
2889 if (btrfs_key_type(&found_key) != BTRFS_EXTENT_ITEM_KEY ||
2890 found_key.objectid + found_key.offset <= cur_byte) {
2896 cur_byte = found_key.objectid + found_key.offset;
2897 key.objectid = cur_byte;
2898 btrfs_release_path(root, path);
2899 ret = relocate_one_extent(root, path, &found_key);
2902 btrfs_release_path(root, path);
2904 if (total_found > 0) {
2905 printk("btrfs relocate found %llu last extent was %llu\n",
2906 (unsigned long long)total_found,
2907 (unsigned long long)found_key.objectid);
2908 trans = btrfs_start_transaction(tree_root, 1);
2909 btrfs_commit_transaction(trans, tree_root);
2911 mutex_unlock(&root->fs_info->fs_mutex);
2912 btrfs_clean_old_snapshots(tree_root);
2913 mutex_lock(&root->fs_info->fs_mutex);
2915 trans = btrfs_start_transaction(tree_root, 1);
2916 btrfs_commit_transaction(trans, tree_root);
2921 * we've freed all the extents, now remove the block
2922 * group item from the tree
2924 trans = btrfs_start_transaction(root, 1);
2925 memcpy(&key, &shrink_block_group->key, sizeof(key));
2927 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2933 leaf = path->nodes[0];
2934 nritems = btrfs_header_nritems(leaf);
2935 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2936 kfree(shrink_block_group);
2938 clear_extent_bits(&info->block_group_cache, found_key.objectid,
2939 found_key.objectid + found_key.offset - 1,
2940 (unsigned int)-1, GFP_NOFS);
2942 btrfs_del_item(trans, root, path);
2943 clear_extent_dirty(&info->free_space_cache,
2944 shrink_start, shrink_last_byte - 1,
2946 btrfs_commit_transaction(trans, root);
2948 btrfs_free_path(path);
2952 int find_first_block_group(struct btrfs_root *root, struct btrfs_path *path,
2953 struct btrfs_key *key)
2956 struct btrfs_key found_key;
2957 struct extent_buffer *leaf;
2960 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
2964 slot = path->slots[0];
2965 leaf = path->nodes[0];
2966 if (slot >= btrfs_header_nritems(leaf)) {
2967 ret = btrfs_next_leaf(root, path);
2974 btrfs_item_key_to_cpu(leaf, &found_key, slot);
2976 if (found_key.objectid >= key->objectid &&
2977 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY)
2986 int btrfs_read_block_groups(struct btrfs_root *root)
2988 struct btrfs_path *path;
2991 struct btrfs_block_group_cache *cache;
2992 struct btrfs_fs_info *info = root->fs_info;
2993 struct btrfs_space_info *space_info;
2994 struct extent_io_tree *block_group_cache;
2995 struct btrfs_key key;
2996 struct btrfs_key found_key;
2997 struct extent_buffer *leaf;
2999 block_group_cache = &info->block_group_cache;
3000 root = info->extent_root;
3003 btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
3004 path = btrfs_alloc_path();
3009 ret = find_first_block_group(root, path, &key);
3017 leaf = path->nodes[0];
3018 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3019 cache = kzalloc(sizeof(*cache), GFP_NOFS);
3025 read_extent_buffer(leaf, &cache->item,
3026 btrfs_item_ptr_offset(leaf, path->slots[0]),
3027 sizeof(cache->item));
3028 memcpy(&cache->key, &found_key, sizeof(found_key));
3030 key.objectid = found_key.objectid + found_key.offset;
3031 btrfs_release_path(root, path);
3032 cache->flags = btrfs_block_group_flags(&cache->item);
3034 if (cache->flags & BTRFS_BLOCK_GROUP_DATA) {
3035 bit = BLOCK_GROUP_DATA;
3036 } else if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM) {
3037 bit = BLOCK_GROUP_SYSTEM;
3038 } else if (cache->flags & BTRFS_BLOCK_GROUP_METADATA) {
3039 bit = BLOCK_GROUP_METADATA;
3041 set_avail_alloc_bits(info, cache->flags);
3043 ret = update_space_info(info, cache->flags, found_key.offset,
3044 btrfs_block_group_used(&cache->item),
3047 cache->space_info = space_info;
3049 /* use EXTENT_LOCKED to prevent merging */
3050 set_extent_bits(block_group_cache, found_key.objectid,
3051 found_key.objectid + found_key.offset - 1,
3052 bit | EXTENT_LOCKED, GFP_NOFS);
3053 set_state_private(block_group_cache, found_key.objectid,
3054 (unsigned long)cache);
3057 btrfs_super_total_bytes(&info->super_copy))
3062 btrfs_free_path(path);
3066 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
3067 struct btrfs_root *root, u64 bytes_used,
3068 u64 type, u64 chunk_objectid, u64 chunk_offset,
3073 struct btrfs_root *extent_root;
3074 struct btrfs_block_group_cache *cache;
3075 struct extent_io_tree *block_group_cache;
3077 extent_root = root->fs_info->extent_root;
3078 block_group_cache = &root->fs_info->block_group_cache;
3080 cache = kzalloc(sizeof(*cache), GFP_NOFS);
3082 cache->key.objectid = chunk_offset;
3083 cache->key.offset = size;
3085 btrfs_set_key_type(&cache->key, BTRFS_BLOCK_GROUP_ITEM_KEY);
3086 memset(&cache->item, 0, sizeof(cache->item));
3087 btrfs_set_block_group_used(&cache->item, bytes_used);
3088 btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
3089 cache->flags = type;
3090 btrfs_set_block_group_flags(&cache->item, type);
3092 ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
3093 &cache->space_info);
3096 bit = block_group_state_bits(type);
3097 set_extent_bits(block_group_cache, chunk_offset,
3098 chunk_offset + size - 1,
3099 bit | EXTENT_LOCKED, GFP_NOFS);
3101 set_state_private(block_group_cache, chunk_offset,
3102 (unsigned long)cache);
3103 ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
3104 sizeof(cache->item));
3107 finish_current_insert(trans, extent_root);
3108 ret = del_pending_extents(trans, extent_root);
3110 set_avail_alloc_bits(extent_root->fs_info, type);