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Btrfs: Bring back mount -o ssd optimizations
[deliverable/linux.git] / fs / btrfs / extent-tree.c
1 /*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
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.
7 *
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.
12 *
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.
17 */
18
19 #include <linux/sched.h>
20 #include <linux/crc32c.h>
21 #include <linux/pagemap.h>
22 #include "hash.h"
23 #include "ctree.h"
24 #include "disk-io.h"
25 #include "print-tree.h"
26 #include "transaction.h"
27 #include "volumes.h"
28
29 #define BLOCK_GROUP_DATA EXTENT_WRITEBACK
30 #define BLOCK_GROUP_METADATA EXTENT_UPTODATE
31 #define BLOCK_GROUP_SYSTEM EXTENT_NEW
32
33 #define BLOCK_GROUP_DIRTY EXTENT_DIRTY
34
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);
39 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
40 struct btrfs_root *root, u64 bytes_used,
41 u64 type, u64 chunk_tree, u64 chunk_objectid,
42 u64 size);
43
44
45 static int cache_block_group(struct btrfs_root *root,
46 struct btrfs_block_group_cache *block_group)
47 {
48 struct btrfs_path *path;
49 int ret;
50 struct btrfs_key key;
51 struct extent_buffer *leaf;
52 struct extent_io_tree *free_space_cache;
53 int slot;
54 u64 last = 0;
55 u64 hole_size;
56 u64 first_free;
57 int found = 0;
58
59 if (!block_group)
60 return 0;
61
62 root = root->fs_info->extent_root;
63 free_space_cache = &root->fs_info->free_space_cache;
64
65 if (block_group->cached)
66 return 0;
67
68 path = btrfs_alloc_path();
69 if (!path)
70 return -ENOMEM;
71
72 path->reada = 2;
73 first_free = block_group->key.objectid;
74 key.objectid = block_group->key.objectid;
75 key.offset = 0;
76 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
77 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
78 if (ret < 0)
79 return ret;
80 ret = btrfs_previous_item(root, path, 0, BTRFS_EXTENT_ITEM_KEY);
81 if (ret < 0)
82 return ret;
83 if (ret == 0) {
84 leaf = path->nodes[0];
85 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
86 if (key.objectid + key.offset > first_free)
87 first_free = key.objectid + key.offset;
88 }
89 while(1) {
90 leaf = path->nodes[0];
91 slot = path->slots[0];
92 if (slot >= btrfs_header_nritems(leaf)) {
93 ret = btrfs_next_leaf(root, path);
94 if (ret < 0)
95 goto err;
96 if (ret == 0) {
97 continue;
98 } else {
99 break;
100 }
101 }
102 btrfs_item_key_to_cpu(leaf, &key, slot);
103 if (key.objectid < block_group->key.objectid) {
104 goto next;
105 }
106 if (key.objectid >= block_group->key.objectid +
107 block_group->key.offset) {
108 break;
109 }
110
111 if (btrfs_key_type(&key) == BTRFS_EXTENT_ITEM_KEY) {
112 if (!found) {
113 last = first_free;
114 found = 1;
115 }
116 if (key.objectid > last) {
117 hole_size = key.objectid - last;
118 set_extent_dirty(free_space_cache, last,
119 last + hole_size - 1,
120 GFP_NOFS);
121 }
122 last = key.objectid + key.offset;
123 }
124 next:
125 path->slots[0]++;
126 }
127
128 if (!found)
129 last = first_free;
130 if (block_group->key.objectid +
131 block_group->key.offset > last) {
132 hole_size = block_group->key.objectid +
133 block_group->key.offset - last;
134 set_extent_dirty(free_space_cache, last,
135 last + hole_size - 1, GFP_NOFS);
136 }
137 block_group->cached = 1;
138 err:
139 btrfs_free_path(path);
140 return 0;
141 }
142
143 struct btrfs_block_group_cache *btrfs_lookup_block_group(struct
144 btrfs_fs_info *info,
145 u64 bytenr)
146 {
147 struct extent_io_tree *block_group_cache;
148 struct btrfs_block_group_cache *block_group = NULL;
149 u64 ptr;
150 u64 start;
151 u64 end;
152 int ret;
153
154 block_group_cache = &info->block_group_cache;
155 ret = find_first_extent_bit(block_group_cache,
156 bytenr, &start, &end,
157 BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA |
158 BLOCK_GROUP_SYSTEM);
159 if (ret) {
160 return NULL;
161 }
162 ret = get_state_private(block_group_cache, start, &ptr);
163 if (ret)
164 return NULL;
165
166 block_group = (struct btrfs_block_group_cache *)(unsigned long)ptr;
167 if (block_group->key.objectid <= bytenr && bytenr <
168 block_group->key.objectid + block_group->key.offset)
169 return block_group;
170 return NULL;
171 }
172
173 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
174 {
175 return (cache->flags & bits);
176 }
177
178 static int noinline find_search_start(struct btrfs_root *root,
179 struct btrfs_block_group_cache **cache_ret,
180 u64 *start_ret, int num, int data)
181 {
182 int ret;
183 struct btrfs_block_group_cache *cache = *cache_ret;
184 struct extent_io_tree *free_space_cache;
185 struct extent_state *state;
186 u64 last;
187 u64 start = 0;
188 u64 cache_miss = 0;
189 u64 total_fs_bytes;
190 u64 search_start = *start_ret;
191 int wrapped = 0;
192
193 if (!cache)
194 goto out;
195 total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
196 free_space_cache = &root->fs_info->free_space_cache;
197
198 again:
199 ret = cache_block_group(root, cache);
200 if (ret)
201 goto out;
202
203 last = max(search_start, cache->key.objectid);
204 if (!block_group_bits(cache, data)) {
205 goto new_group;
206 }
207
208 spin_lock_irq(&free_space_cache->lock);
209 state = find_first_extent_bit_state(free_space_cache, last, EXTENT_DIRTY);
210 while(1) {
211 if (!state) {
212 if (!cache_miss)
213 cache_miss = last;
214 spin_unlock_irq(&free_space_cache->lock);
215 goto new_group;
216 }
217
218 start = max(last, state->start);
219 last = state->end + 1;
220 if (last - start < num) {
221 if (last == cache->key.objectid + cache->key.offset)
222 cache_miss = start;
223 do {
224 state = extent_state_next(state);
225 } while(state && !(state->state & EXTENT_DIRTY));
226 continue;
227 }
228 spin_unlock_irq(&free_space_cache->lock);
229 if (start + num > cache->key.objectid + cache->key.offset)
230 goto new_group;
231 if (start + num > total_fs_bytes)
232 goto new_group;
233 *start_ret = start;
234 return 0;
235 } out:
236 cache = btrfs_lookup_block_group(root->fs_info, search_start);
237 if (!cache) {
238 printk("Unable to find block group for %Lu\n", search_start);
239 WARN_ON(1);
240 }
241 return -ENOSPC;
242
243 new_group:
244 last = cache->key.objectid + cache->key.offset;
245 wrapped:
246 cache = btrfs_lookup_block_group(root->fs_info, last);
247 if (!cache || cache->key.objectid >= total_fs_bytes) {
248 no_cache:
249 if (!wrapped) {
250 wrapped = 1;
251 last = search_start;
252 goto wrapped;
253 }
254 goto out;
255 }
256 if (cache_miss && !cache->cached) {
257 cache_block_group(root, cache);
258 last = cache_miss;
259 cache = btrfs_lookup_block_group(root->fs_info, last);
260 }
261 cache = btrfs_find_block_group(root, cache, last, data, 0);
262 if (!cache)
263 goto no_cache;
264 *cache_ret = cache;
265 cache_miss = 0;
266 goto again;
267 }
268
269 static u64 div_factor(u64 num, int factor)
270 {
271 if (factor == 10)
272 return num;
273 num *= factor;
274 do_div(num, 10);
275 return num;
276 }
277
278 static int block_group_state_bits(u64 flags)
279 {
280 int bits = 0;
281 if (flags & BTRFS_BLOCK_GROUP_DATA)
282 bits |= BLOCK_GROUP_DATA;
283 if (flags & BTRFS_BLOCK_GROUP_METADATA)
284 bits |= BLOCK_GROUP_METADATA;
285 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
286 bits |= BLOCK_GROUP_SYSTEM;
287 return bits;
288 }
289
290 struct btrfs_block_group_cache *btrfs_find_block_group(struct btrfs_root *root,
291 struct btrfs_block_group_cache
292 *hint, u64 search_start,
293 int data, int owner)
294 {
295 struct btrfs_block_group_cache *cache;
296 struct extent_io_tree *block_group_cache;
297 struct btrfs_block_group_cache *found_group = NULL;
298 struct btrfs_fs_info *info = root->fs_info;
299 u64 used;
300 u64 last = 0;
301 u64 hint_last;
302 u64 start;
303 u64 end;
304 u64 free_check;
305 u64 ptr;
306 u64 total_fs_bytes;
307 int bit;
308 int ret;
309 int full_search = 0;
310 int factor = 8;
311
312 block_group_cache = &info->block_group_cache;
313 total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
314
315 if (!owner)
316 factor = 8;
317
318 bit = block_group_state_bits(data);
319
320 if (search_start && search_start < total_fs_bytes) {
321 struct btrfs_block_group_cache *shint;
322 shint = btrfs_lookup_block_group(info, search_start);
323 if (shint && block_group_bits(shint, data)) {
324 used = btrfs_block_group_used(&shint->item);
325 if (used + shint->pinned <
326 div_factor(shint->key.offset, factor)) {
327 return shint;
328 }
329 }
330 }
331 if (hint && block_group_bits(hint, data) &&
332 hint->key.objectid < total_fs_bytes) {
333 used = btrfs_block_group_used(&hint->item);
334 if (used + hint->pinned <
335 div_factor(hint->key.offset, factor)) {
336 return hint;
337 }
338 last = hint->key.objectid + hint->key.offset;
339 hint_last = last;
340 } else {
341 if (hint)
342 hint_last = max(hint->key.objectid, search_start);
343 else
344 hint_last = search_start;
345
346 if (hint_last >= total_fs_bytes)
347 hint_last = search_start;
348 last = hint_last;
349 }
350 again:
351 while(1) {
352 ret = find_first_extent_bit(block_group_cache, last,
353 &start, &end, bit);
354 if (ret)
355 break;
356
357 ret = get_state_private(block_group_cache, start, &ptr);
358 if (ret)
359 break;
360
361 cache = (struct btrfs_block_group_cache *)(unsigned long)ptr;
362 last = cache->key.objectid + cache->key.offset;
363 used = btrfs_block_group_used(&cache->item);
364
365 if (cache->key.objectid > total_fs_bytes)
366 break;
367
368 if (full_search)
369 free_check = cache->key.offset;
370 else
371 free_check = div_factor(cache->key.offset, factor);
372
373 if (used + cache->pinned < free_check) {
374 found_group = cache;
375 goto found;
376 }
377 cond_resched();
378 }
379 if (!full_search) {
380 last = search_start;
381 full_search = 1;
382 goto again;
383 }
384 found:
385 return found_group;
386 }
387
388 static u64 hash_extent_ref(u64 root_objectid, u64 ref_generation,
389 u64 owner, u64 owner_offset)
390 {
391 u32 high_crc = ~(u32)0;
392 u32 low_crc = ~(u32)0;
393 __le64 lenum;
394
395 lenum = cpu_to_le64(root_objectid);
396 high_crc = crc32c(high_crc, &lenum, sizeof(lenum));
397 lenum = cpu_to_le64(ref_generation);
398 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
399 if (owner >= BTRFS_FIRST_FREE_OBJECTID) {
400 lenum = cpu_to_le64(owner);
401 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
402 lenum = cpu_to_le64(owner_offset);
403 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
404 }
405 return ((u64)high_crc << 32) | (u64)low_crc;
406 }
407
408 static int match_extent_ref(struct extent_buffer *leaf,
409 struct btrfs_extent_ref *disk_ref,
410 struct btrfs_extent_ref *cpu_ref)
411 {
412 int ret;
413 int len;
414
415 if (cpu_ref->objectid)
416 len = sizeof(*cpu_ref);
417 else
418 len = 2 * sizeof(u64);
419 ret = memcmp_extent_buffer(leaf, cpu_ref, (unsigned long)disk_ref,
420 len);
421 return ret == 0;
422 }
423
424 static int noinline lookup_extent_backref(struct btrfs_trans_handle *trans,
425 struct btrfs_root *root,
426 struct btrfs_path *path, u64 bytenr,
427 u64 root_objectid,
428 u64 ref_generation, u64 owner,
429 u64 owner_offset, int del)
430 {
431 u64 hash;
432 struct btrfs_key key;
433 struct btrfs_key found_key;
434 struct btrfs_extent_ref ref;
435 struct extent_buffer *leaf;
436 struct btrfs_extent_ref *disk_ref;
437 int ret;
438 int ret2;
439
440 btrfs_set_stack_ref_root(&ref, root_objectid);
441 btrfs_set_stack_ref_generation(&ref, ref_generation);
442 btrfs_set_stack_ref_objectid(&ref, owner);
443 btrfs_set_stack_ref_offset(&ref, owner_offset);
444
445 hash = hash_extent_ref(root_objectid, ref_generation, owner,
446 owner_offset);
447 key.offset = hash;
448 key.objectid = bytenr;
449 key.type = BTRFS_EXTENT_REF_KEY;
450
451 while (1) {
452 ret = btrfs_search_slot(trans, root, &key, path,
453 del ? -1 : 0, del);
454 if (ret < 0)
455 goto out;
456 leaf = path->nodes[0];
457 if (ret != 0) {
458 u32 nritems = btrfs_header_nritems(leaf);
459 if (path->slots[0] >= nritems) {
460 ret2 = btrfs_next_leaf(root, path);
461 if (ret2)
462 goto out;
463 leaf = path->nodes[0];
464 }
465 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
466 if (found_key.objectid != bytenr ||
467 found_key.type != BTRFS_EXTENT_REF_KEY)
468 goto out;
469 key.offset = found_key.offset;
470 if (del) {
471 btrfs_release_path(root, path);
472 continue;
473 }
474 }
475 disk_ref = btrfs_item_ptr(path->nodes[0],
476 path->slots[0],
477 struct btrfs_extent_ref);
478 if (match_extent_ref(path->nodes[0], disk_ref, &ref)) {
479 ret = 0;
480 goto out;
481 }
482 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
483 key.offset = found_key.offset + 1;
484 btrfs_release_path(root, path);
485 }
486 out:
487 return ret;
488 }
489
490 /*
491 * Back reference rules. Back refs have three main goals:
492 *
493 * 1) differentiate between all holders of references to an extent so that
494 * when a reference is dropped we can make sure it was a valid reference
495 * before freeing the extent.
496 *
497 * 2) Provide enough information to quickly find the holders of an extent
498 * if we notice a given block is corrupted or bad.
499 *
500 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
501 * maintenance. This is actually the same as #2, but with a slightly
502 * different use case.
503 *
504 * File extents can be referenced by:
505 *
506 * - multiple snapshots, subvolumes, or different generations in one subvol
507 * - different files inside a single subvolume (in theory, not implemented yet)
508 * - different offsets inside a file (bookend extents in file.c)
509 *
510 * The extent ref structure has fields for:
511 *
512 * - Objectid of the subvolume root
513 * - Generation number of the tree holding the reference
514 * - objectid of the file holding the reference
515 * - offset in the file corresponding to the key holding the reference
516 *
517 * When a file extent is allocated the fields are filled in:
518 * (root_key.objectid, trans->transid, inode objectid, offset in file)
519 *
520 * When a leaf is cow'd new references are added for every file extent found
521 * in the leaf. It looks the same as the create case, but trans->transid
522 * will be different when the block is cow'd.
523 *
524 * (root_key.objectid, trans->transid, inode objectid, offset in file)
525 *
526 * When a file extent is removed either during snapshot deletion or file
527 * truncation, the corresponding back reference is found
528 * by searching for:
529 *
530 * (btrfs_header_owner(leaf), btrfs_header_generation(leaf),
531 * inode objectid, offset in file)
532 *
533 * Btree extents can be referenced by:
534 *
535 * - Different subvolumes
536 * - Different generations of the same subvolume
537 *
538 * Storing sufficient information for a full reverse mapping of a btree
539 * block would require storing the lowest key of the block in the backref,
540 * and it would require updating that lowest key either before write out or
541 * every time it changed. Instead, the objectid of the lowest key is stored
542 * along with the level of the tree block. This provides a hint
543 * about where in the btree the block can be found. Searches through the
544 * btree only need to look for a pointer to that block, so they stop one
545 * level higher than the level recorded in the backref.
546 *
547 * Some btrees do not do reference counting on their extents. These
548 * include the extent tree and the tree of tree roots. Backrefs for these
549 * trees always have a generation of zero.
550 *
551 * When a tree block is created, back references are inserted:
552 *
553 * (root->root_key.objectid, trans->transid or zero, level, lowest_key_objectid)
554 *
555 * When a tree block is cow'd in a reference counted root,
556 * new back references are added for all the blocks it points to.
557 * These are of the form (trans->transid will have increased since creation):
558 *
559 * (root->root_key.objectid, trans->transid, level, lowest_key_objectid)
560 *
561 * Because the lowest_key_objectid and the level are just hints
562 * they are not used when backrefs are deleted. When a backref is deleted:
563 *
564 * if backref was for a tree root:
565 * root_objectid = root->root_key.objectid
566 * else
567 * root_objectid = btrfs_header_owner(parent)
568 *
569 * (root_objectid, btrfs_header_generation(parent) or zero, 0, 0)
570 *
571 * Back Reference Key hashing:
572 *
573 * Back references have four fields, each 64 bits long. Unfortunately,
574 * This is hashed into a single 64 bit number and placed into the key offset.
575 * The key objectid corresponds to the first byte in the extent, and the
576 * key type is set to BTRFS_EXTENT_REF_KEY
577 */
578 int btrfs_insert_extent_backref(struct btrfs_trans_handle *trans,
579 struct btrfs_root *root,
580 struct btrfs_path *path, u64 bytenr,
581 u64 root_objectid, u64 ref_generation,
582 u64 owner, u64 owner_offset)
583 {
584 u64 hash;
585 struct btrfs_key key;
586 struct btrfs_extent_ref ref;
587 struct btrfs_extent_ref *disk_ref;
588 int ret;
589
590 btrfs_set_stack_ref_root(&ref, root_objectid);
591 btrfs_set_stack_ref_generation(&ref, ref_generation);
592 btrfs_set_stack_ref_objectid(&ref, owner);
593 btrfs_set_stack_ref_offset(&ref, owner_offset);
594
595 hash = hash_extent_ref(root_objectid, ref_generation, owner,
596 owner_offset);
597 key.offset = hash;
598 key.objectid = bytenr;
599 key.type = BTRFS_EXTENT_REF_KEY;
600
601 ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(ref));
602 while (ret == -EEXIST) {
603 disk_ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
604 struct btrfs_extent_ref);
605 if (match_extent_ref(path->nodes[0], disk_ref, &ref))
606 goto out;
607 key.offset++;
608 btrfs_release_path(root, path);
609 ret = btrfs_insert_empty_item(trans, root, path, &key,
610 sizeof(ref));
611 }
612 if (ret)
613 goto out;
614 disk_ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
615 struct btrfs_extent_ref);
616 write_extent_buffer(path->nodes[0], &ref, (unsigned long)disk_ref,
617 sizeof(ref));
618 btrfs_mark_buffer_dirty(path->nodes[0]);
619 out:
620 btrfs_release_path(root, path);
621 return ret;
622 }
623
624 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
625 struct btrfs_root *root,
626 u64 bytenr, u64 num_bytes,
627 u64 root_objectid, u64 ref_generation,
628 u64 owner, u64 owner_offset)
629 {
630 struct btrfs_path *path;
631 int ret;
632 struct btrfs_key key;
633 struct extent_buffer *l;
634 struct btrfs_extent_item *item;
635 u32 refs;
636
637 WARN_ON(num_bytes < root->sectorsize);
638 path = btrfs_alloc_path();
639 if (!path)
640 return -ENOMEM;
641
642 path->reada = 0;
643 key.objectid = bytenr;
644 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
645 key.offset = num_bytes;
646 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path,
647 0, 1);
648 if (ret < 0)
649 return ret;
650 if (ret != 0) {
651 BUG();
652 }
653 BUG_ON(ret != 0);
654 l = path->nodes[0];
655 item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
656 refs = btrfs_extent_refs(l, item);
657 btrfs_set_extent_refs(l, item, refs + 1);
658 btrfs_mark_buffer_dirty(path->nodes[0]);
659
660 btrfs_release_path(root->fs_info->extent_root, path);
661
662 path->reada = 0;
663 ret = btrfs_insert_extent_backref(trans, root->fs_info->extent_root,
664 path, bytenr, root_objectid,
665 ref_generation, owner, owner_offset);
666 BUG_ON(ret);
667 finish_current_insert(trans, root->fs_info->extent_root);
668 del_pending_extents(trans, root->fs_info->extent_root);
669
670 btrfs_free_path(path);
671 return 0;
672 }
673
674 int btrfs_extent_post_op(struct btrfs_trans_handle *trans,
675 struct btrfs_root *root)
676 {
677 finish_current_insert(trans, root->fs_info->extent_root);
678 del_pending_extents(trans, root->fs_info->extent_root);
679 return 0;
680 }
681
682 static int lookup_extent_ref(struct btrfs_trans_handle *trans,
683 struct btrfs_root *root, u64 bytenr,
684 u64 num_bytes, u32 *refs)
685 {
686 struct btrfs_path *path;
687 int ret;
688 struct btrfs_key key;
689 struct extent_buffer *l;
690 struct btrfs_extent_item *item;
691
692 WARN_ON(num_bytes < root->sectorsize);
693 path = btrfs_alloc_path();
694 path->reada = 0;
695 key.objectid = bytenr;
696 key.offset = num_bytes;
697 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
698 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path,
699 0, 0);
700 if (ret < 0)
701 goto out;
702 if (ret != 0) {
703 btrfs_print_leaf(root, path->nodes[0]);
704 printk("failed to find block number %Lu\n", bytenr);
705 BUG();
706 }
707 l = path->nodes[0];
708 item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
709 *refs = btrfs_extent_refs(l, item);
710 out:
711 btrfs_free_path(path);
712 return 0;
713 }
714
715 u32 btrfs_count_snapshots_in_path(struct btrfs_root *root,
716 struct btrfs_path *count_path,
717 u64 first_extent)
718 {
719 struct btrfs_root *extent_root = root->fs_info->extent_root;
720 struct btrfs_path *path;
721 u64 bytenr;
722 u64 found_objectid;
723 u64 root_objectid = root->root_key.objectid;
724 u32 total_count = 0;
725 u32 cur_count;
726 u32 nritems;
727 int ret;
728 struct btrfs_key key;
729 struct btrfs_key found_key;
730 struct extent_buffer *l;
731 struct btrfs_extent_item *item;
732 struct btrfs_extent_ref *ref_item;
733 int level = -1;
734
735 path = btrfs_alloc_path();
736 again:
737 if (level == -1)
738 bytenr = first_extent;
739 else
740 bytenr = count_path->nodes[level]->start;
741
742 cur_count = 0;
743 key.objectid = bytenr;
744 key.offset = 0;
745
746 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
747 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
748 if (ret < 0)
749 goto out;
750 BUG_ON(ret == 0);
751
752 l = path->nodes[0];
753 btrfs_item_key_to_cpu(l, &found_key, path->slots[0]);
754
755 if (found_key.objectid != bytenr ||
756 found_key.type != BTRFS_EXTENT_ITEM_KEY) {
757 goto out;
758 }
759
760 item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
761 while (1) {
762 l = path->nodes[0];
763 nritems = btrfs_header_nritems(l);
764 if (path->slots[0] >= nritems) {
765 ret = btrfs_next_leaf(extent_root, path);
766 if (ret == 0)
767 continue;
768 break;
769 }
770 btrfs_item_key_to_cpu(l, &found_key, path->slots[0]);
771 if (found_key.objectid != bytenr)
772 break;
773
774 if (found_key.type != BTRFS_EXTENT_REF_KEY) {
775 path->slots[0]++;
776 continue;
777 }
778
779 cur_count++;
780 ref_item = btrfs_item_ptr(l, path->slots[0],
781 struct btrfs_extent_ref);
782 found_objectid = btrfs_ref_root(l, ref_item);
783
784 if (found_objectid != root_objectid) {
785 total_count = 2;
786 goto out;
787 }
788 total_count = 1;
789 path->slots[0]++;
790 }
791 if (cur_count == 0) {
792 total_count = 0;
793 goto out;
794 }
795 if (level >= 0 && root->node == count_path->nodes[level])
796 goto out;
797 level++;
798 btrfs_release_path(root, path);
799 goto again;
800
801 out:
802 btrfs_free_path(path);
803 return total_count;
804 }
805 int btrfs_inc_root_ref(struct btrfs_trans_handle *trans,
806 struct btrfs_root *root, u64 owner_objectid)
807 {
808 u64 generation;
809 u64 key_objectid;
810 u64 level;
811 u32 nritems;
812 struct btrfs_disk_key disk_key;
813
814 level = btrfs_header_level(root->node);
815 generation = trans->transid;
816 nritems = btrfs_header_nritems(root->node);
817 if (nritems > 0) {
818 if (level == 0)
819 btrfs_item_key(root->node, &disk_key, 0);
820 else
821 btrfs_node_key(root->node, &disk_key, 0);
822 key_objectid = btrfs_disk_key_objectid(&disk_key);
823 } else {
824 key_objectid = 0;
825 }
826 return btrfs_inc_extent_ref(trans, root, root->node->start,
827 root->node->len, owner_objectid,
828 generation, level, key_objectid);
829 }
830
831 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
832 struct extent_buffer *buf)
833 {
834 u64 bytenr;
835 u32 nritems;
836 struct btrfs_key key;
837 struct btrfs_file_extent_item *fi;
838 int i;
839 int level;
840 int ret;
841 int faili;
842
843 if (!root->ref_cows)
844 return 0;
845
846 level = btrfs_header_level(buf);
847 nritems = btrfs_header_nritems(buf);
848 for (i = 0; i < nritems; i++) {
849 if (level == 0) {
850 u64 disk_bytenr;
851 btrfs_item_key_to_cpu(buf, &key, i);
852 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
853 continue;
854 fi = btrfs_item_ptr(buf, i,
855 struct btrfs_file_extent_item);
856 if (btrfs_file_extent_type(buf, fi) ==
857 BTRFS_FILE_EXTENT_INLINE)
858 continue;
859 disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
860 if (disk_bytenr == 0)
861 continue;
862 ret = btrfs_inc_extent_ref(trans, root, disk_bytenr,
863 btrfs_file_extent_disk_num_bytes(buf, fi),
864 root->root_key.objectid, trans->transid,
865 key.objectid, key.offset);
866 if (ret) {
867 faili = i;
868 goto fail;
869 }
870 } else {
871 bytenr = btrfs_node_blockptr(buf, i);
872 btrfs_node_key_to_cpu(buf, &key, i);
873 ret = btrfs_inc_extent_ref(trans, root, bytenr,
874 btrfs_level_size(root, level - 1),
875 root->root_key.objectid,
876 trans->transid,
877 level - 1, key.objectid);
878 if (ret) {
879 faili = i;
880 goto fail;
881 }
882 }
883 }
884 return 0;
885 fail:
886 WARN_ON(1);
887 #if 0
888 for (i =0; i < faili; i++) {
889 if (level == 0) {
890 u64 disk_bytenr;
891 btrfs_item_key_to_cpu(buf, &key, i);
892 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
893 continue;
894 fi = btrfs_item_ptr(buf, i,
895 struct btrfs_file_extent_item);
896 if (btrfs_file_extent_type(buf, fi) ==
897 BTRFS_FILE_EXTENT_INLINE)
898 continue;
899 disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
900 if (disk_bytenr == 0)
901 continue;
902 err = btrfs_free_extent(trans, root, disk_bytenr,
903 btrfs_file_extent_disk_num_bytes(buf,
904 fi), 0);
905 BUG_ON(err);
906 } else {
907 bytenr = btrfs_node_blockptr(buf, i);
908 err = btrfs_free_extent(trans, root, bytenr,
909 btrfs_level_size(root, level - 1), 0);
910 BUG_ON(err);
911 }
912 }
913 #endif
914 return ret;
915 }
916
917 static int write_one_cache_group(struct btrfs_trans_handle *trans,
918 struct btrfs_root *root,
919 struct btrfs_path *path,
920 struct btrfs_block_group_cache *cache)
921 {
922 int ret;
923 int pending_ret;
924 struct btrfs_root *extent_root = root->fs_info->extent_root;
925 unsigned long bi;
926 struct extent_buffer *leaf;
927
928 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
929 if (ret < 0)
930 goto fail;
931 BUG_ON(ret);
932
933 leaf = path->nodes[0];
934 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
935 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
936 btrfs_mark_buffer_dirty(leaf);
937 btrfs_release_path(extent_root, path);
938 fail:
939 finish_current_insert(trans, extent_root);
940 pending_ret = del_pending_extents(trans, extent_root);
941 if (ret)
942 return ret;
943 if (pending_ret)
944 return pending_ret;
945 return 0;
946
947 }
948
949 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
950 struct btrfs_root *root)
951 {
952 struct extent_io_tree *block_group_cache;
953 struct btrfs_block_group_cache *cache;
954 int ret;
955 int err = 0;
956 int werr = 0;
957 struct btrfs_path *path;
958 u64 last = 0;
959 u64 start;
960 u64 end;
961 u64 ptr;
962
963 block_group_cache = &root->fs_info->block_group_cache;
964 path = btrfs_alloc_path();
965 if (!path)
966 return -ENOMEM;
967
968 while(1) {
969 ret = find_first_extent_bit(block_group_cache, last,
970 &start, &end, BLOCK_GROUP_DIRTY);
971 if (ret)
972 break;
973
974 last = end + 1;
975 ret = get_state_private(block_group_cache, start, &ptr);
976 if (ret)
977 break;
978
979 cache = (struct btrfs_block_group_cache *)(unsigned long)ptr;
980 err = write_one_cache_group(trans, root,
981 path, cache);
982 /*
983 * if we fail to write the cache group, we want
984 * to keep it marked dirty in hopes that a later
985 * write will work
986 */
987 if (err) {
988 werr = err;
989 continue;
990 }
991 clear_extent_bits(block_group_cache, start, end,
992 BLOCK_GROUP_DIRTY, GFP_NOFS);
993 }
994 btrfs_free_path(path);
995 return werr;
996 }
997
998 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
999 u64 flags)
1000 {
1001 struct list_head *head = &info->space_info;
1002 struct list_head *cur;
1003 struct btrfs_space_info *found;
1004 list_for_each(cur, head) {
1005 found = list_entry(cur, struct btrfs_space_info, list);
1006 if (found->flags == flags)
1007 return found;
1008 }
1009 return NULL;
1010
1011 }
1012
1013 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
1014 struct btrfs_root *extent_root, u64 alloc_bytes,
1015 u64 flags)
1016 {
1017 struct btrfs_space_info *space_info;
1018 u64 thresh;
1019 u64 start;
1020 u64 num_bytes;
1021 int ret;
1022
1023 space_info = __find_space_info(extent_root->fs_info, flags);
1024 BUG_ON(!space_info);
1025
1026 if (space_info->full)
1027 return 0;
1028
1029 thresh = div_factor(space_info->total_bytes, 7);
1030 if ((space_info->bytes_used + space_info->bytes_pinned + alloc_bytes) <
1031 thresh)
1032 return 0;
1033
1034 ret = btrfs_alloc_chunk(trans, extent_root, &start, &num_bytes, flags);
1035 if (ret == -ENOSPC) {
1036 printk("space info full %Lu\n", flags);
1037 space_info->full = 1;
1038 return 0;
1039 }
1040
1041 BUG_ON(ret);
1042
1043 ret = btrfs_make_block_group(trans, extent_root, 0, flags,
1044 extent_root->fs_info->chunk_root->root_key.objectid,
1045 start, num_bytes);
1046 BUG_ON(ret);
1047 return 0;
1048 }
1049
1050 static int update_block_group(struct btrfs_trans_handle *trans,
1051 struct btrfs_root *root,
1052 u64 bytenr, u64 num_bytes, int alloc,
1053 int mark_free)
1054 {
1055 struct btrfs_block_group_cache *cache;
1056 struct btrfs_fs_info *info = root->fs_info;
1057 u64 total = num_bytes;
1058 u64 old_val;
1059 u64 byte_in_group;
1060 u64 start;
1061 u64 end;
1062
1063 while(total) {
1064 cache = btrfs_lookup_block_group(info, bytenr);
1065 if (!cache) {
1066 return -1;
1067 }
1068 byte_in_group = bytenr - cache->key.objectid;
1069 WARN_ON(byte_in_group > cache->key.offset);
1070 start = cache->key.objectid;
1071 end = start + cache->key.offset - 1;
1072 set_extent_bits(&info->block_group_cache, start, end,
1073 BLOCK_GROUP_DIRTY, GFP_NOFS);
1074
1075 old_val = btrfs_block_group_used(&cache->item);
1076 num_bytes = min(total, cache->key.offset - byte_in_group);
1077 if (alloc) {
1078 old_val += num_bytes;
1079 cache->space_info->bytes_used += num_bytes;
1080 } else {
1081 old_val -= num_bytes;
1082 cache->space_info->bytes_used -= num_bytes;
1083 if (mark_free) {
1084 set_extent_dirty(&info->free_space_cache,
1085 bytenr, bytenr + num_bytes - 1,
1086 GFP_NOFS);
1087 }
1088 }
1089 btrfs_set_block_group_used(&cache->item, old_val);
1090 total -= num_bytes;
1091 bytenr += num_bytes;
1092 }
1093 return 0;
1094 }
1095
1096 static int update_pinned_extents(struct btrfs_root *root,
1097 u64 bytenr, u64 num, int pin)
1098 {
1099 u64 len;
1100 struct btrfs_block_group_cache *cache;
1101 struct btrfs_fs_info *fs_info = root->fs_info;
1102
1103 if (pin) {
1104 set_extent_dirty(&fs_info->pinned_extents,
1105 bytenr, bytenr + num - 1, GFP_NOFS);
1106 } else {
1107 clear_extent_dirty(&fs_info->pinned_extents,
1108 bytenr, bytenr + num - 1, GFP_NOFS);
1109 }
1110 while (num > 0) {
1111 cache = btrfs_lookup_block_group(fs_info, bytenr);
1112 WARN_ON(!cache);
1113 len = min(num, cache->key.offset -
1114 (bytenr - cache->key.objectid));
1115 if (pin) {
1116 cache->pinned += len;
1117 cache->space_info->bytes_pinned += len;
1118 fs_info->total_pinned += len;
1119 } else {
1120 cache->pinned -= len;
1121 cache->space_info->bytes_pinned -= len;
1122 fs_info->total_pinned -= len;
1123 }
1124 bytenr += len;
1125 num -= len;
1126 }
1127 return 0;
1128 }
1129
1130 int btrfs_copy_pinned(struct btrfs_root *root, struct extent_io_tree *copy)
1131 {
1132 u64 last = 0;
1133 u64 start;
1134 u64 end;
1135 struct extent_io_tree *pinned_extents = &root->fs_info->pinned_extents;
1136 int ret;
1137
1138 while(1) {
1139 ret = find_first_extent_bit(pinned_extents, last,
1140 &start, &end, EXTENT_DIRTY);
1141 if (ret)
1142 break;
1143 set_extent_dirty(copy, start, end, GFP_NOFS);
1144 last = end + 1;
1145 }
1146 return 0;
1147 }
1148
1149 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
1150 struct btrfs_root *root,
1151 struct extent_io_tree *unpin)
1152 {
1153 u64 start;
1154 u64 end;
1155 int ret;
1156 struct extent_io_tree *free_space_cache;
1157 free_space_cache = &root->fs_info->free_space_cache;
1158
1159 while(1) {
1160 ret = find_first_extent_bit(unpin, 0, &start, &end,
1161 EXTENT_DIRTY);
1162 if (ret)
1163 break;
1164 update_pinned_extents(root, start, end + 1 - start, 0);
1165 clear_extent_dirty(unpin, start, end, GFP_NOFS);
1166 set_extent_dirty(free_space_cache, start, end, GFP_NOFS);
1167 }
1168 return 0;
1169 }
1170
1171 static int finish_current_insert(struct btrfs_trans_handle *trans,
1172 struct btrfs_root *extent_root)
1173 {
1174 u64 start;
1175 u64 end;
1176 struct btrfs_fs_info *info = extent_root->fs_info;
1177 struct extent_buffer *eb;
1178 struct btrfs_path *path;
1179 struct btrfs_key ins;
1180 struct btrfs_disk_key first;
1181 struct btrfs_extent_item extent_item;
1182 int ret;
1183 int level;
1184 int err = 0;
1185
1186 btrfs_set_stack_extent_refs(&extent_item, 1);
1187 btrfs_set_key_type(&ins, BTRFS_EXTENT_ITEM_KEY);
1188 path = btrfs_alloc_path();
1189
1190 while(1) {
1191 ret = find_first_extent_bit(&info->extent_ins, 0, &start,
1192 &end, EXTENT_LOCKED);
1193 if (ret)
1194 break;
1195
1196 ins.objectid = start;
1197 ins.offset = end + 1 - start;
1198 err = btrfs_insert_item(trans, extent_root, &ins,
1199 &extent_item, sizeof(extent_item));
1200 clear_extent_bits(&info->extent_ins, start, end, EXTENT_LOCKED,
1201 GFP_NOFS);
1202 eb = read_tree_block(extent_root, ins.objectid, ins.offset);
1203 level = btrfs_header_level(eb);
1204 if (level == 0) {
1205 btrfs_item_key(eb, &first, 0);
1206 } else {
1207 btrfs_node_key(eb, &first, 0);
1208 }
1209 err = btrfs_insert_extent_backref(trans, extent_root, path,
1210 start, extent_root->root_key.objectid,
1211 0, level,
1212 btrfs_disk_key_objectid(&first));
1213 BUG_ON(err);
1214 free_extent_buffer(eb);
1215 }
1216 btrfs_free_path(path);
1217 return 0;
1218 }
1219
1220 static int pin_down_bytes(struct btrfs_root *root, u64 bytenr, u32 num_bytes,
1221 int pending)
1222 {
1223 int err = 0;
1224 struct extent_buffer *buf;
1225
1226 if (!pending) {
1227 buf = btrfs_find_tree_block(root, bytenr, num_bytes);
1228 if (buf) {
1229 if (btrfs_buffer_uptodate(buf)) {
1230 u64 transid =
1231 root->fs_info->running_transaction->transid;
1232 u64 header_transid =
1233 btrfs_header_generation(buf);
1234 if (header_transid == transid) {
1235 clean_tree_block(NULL, root, buf);
1236 free_extent_buffer(buf);
1237 return 1;
1238 }
1239 }
1240 free_extent_buffer(buf);
1241 }
1242 update_pinned_extents(root, bytenr, num_bytes, 1);
1243 } else {
1244 set_extent_bits(&root->fs_info->pending_del,
1245 bytenr, bytenr + num_bytes - 1,
1246 EXTENT_LOCKED, GFP_NOFS);
1247 }
1248 BUG_ON(err < 0);
1249 return 0;
1250 }
1251
1252 /*
1253 * remove an extent from the root, returns 0 on success
1254 */
1255 static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
1256 *root, u64 bytenr, u64 num_bytes,
1257 u64 root_objectid, u64 ref_generation,
1258 u64 owner_objectid, u64 owner_offset, int pin,
1259 int mark_free)
1260 {
1261 struct btrfs_path *path;
1262 struct btrfs_key key;
1263 struct btrfs_fs_info *info = root->fs_info;
1264 struct btrfs_root *extent_root = info->extent_root;
1265 struct extent_buffer *leaf;
1266 int ret;
1267 int extent_slot = 0;
1268 int found_extent = 0;
1269 int num_to_del = 1;
1270 struct btrfs_extent_item *ei;
1271 u32 refs;
1272
1273 key.objectid = bytenr;
1274 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
1275 key.offset = num_bytes;
1276 path = btrfs_alloc_path();
1277 if (!path)
1278 return -ENOMEM;
1279
1280 path->reada = 0;
1281 ret = lookup_extent_backref(trans, extent_root, path,
1282 bytenr, root_objectid,
1283 ref_generation,
1284 owner_objectid, owner_offset, 1);
1285 if (ret == 0) {
1286 struct btrfs_key found_key;
1287 extent_slot = path->slots[0];
1288 while(extent_slot > 0) {
1289 extent_slot--;
1290 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1291 extent_slot);
1292 if (found_key.objectid != bytenr)
1293 break;
1294 if (found_key.type == BTRFS_EXTENT_ITEM_KEY &&
1295 found_key.offset == num_bytes) {
1296 found_extent = 1;
1297 break;
1298 }
1299 if (path->slots[0] - extent_slot > 5)
1300 break;
1301 }
1302 if (!found_extent)
1303 ret = btrfs_del_item(trans, extent_root, path);
1304 } else {
1305 btrfs_print_leaf(extent_root, path->nodes[0]);
1306 WARN_ON(1);
1307 printk("Unable to find ref byte nr %Lu root %Lu "
1308 " gen %Lu owner %Lu offset %Lu\n", bytenr,
1309 root_objectid, ref_generation, owner_objectid,
1310 owner_offset);
1311 }
1312 if (!found_extent) {
1313 btrfs_release_path(extent_root, path);
1314 ret = btrfs_search_slot(trans, extent_root, &key, path, -1, 1);
1315 if (ret < 0)
1316 return ret;
1317 BUG_ON(ret);
1318 extent_slot = path->slots[0];
1319 }
1320
1321 leaf = path->nodes[0];
1322 ei = btrfs_item_ptr(leaf, extent_slot,
1323 struct btrfs_extent_item);
1324 refs = btrfs_extent_refs(leaf, ei);
1325 BUG_ON(refs == 0);
1326 refs -= 1;
1327 btrfs_set_extent_refs(leaf, ei, refs);
1328
1329 btrfs_mark_buffer_dirty(leaf);
1330
1331 if (refs == 0 && found_extent && path->slots[0] == extent_slot + 1) {
1332 /* if the back ref and the extent are next to each other
1333 * they get deleted below in one shot
1334 */
1335 path->slots[0] = extent_slot;
1336 num_to_del = 2;
1337 } else if (found_extent) {
1338 /* otherwise delete the extent back ref */
1339 ret = btrfs_del_item(trans, extent_root, path);
1340 BUG_ON(ret);
1341 /* if refs are 0, we need to setup the path for deletion */
1342 if (refs == 0) {
1343 btrfs_release_path(extent_root, path);
1344 ret = btrfs_search_slot(trans, extent_root, &key, path,
1345 -1, 1);
1346 if (ret < 0)
1347 return ret;
1348 BUG_ON(ret);
1349 }
1350 }
1351
1352 if (refs == 0) {
1353 u64 super_used;
1354 u64 root_used;
1355
1356 if (pin) {
1357 ret = pin_down_bytes(root, bytenr, num_bytes, 0);
1358 if (ret > 0)
1359 mark_free = 1;
1360 BUG_ON(ret < 0);
1361 }
1362
1363 /* block accounting for super block */
1364 super_used = btrfs_super_bytes_used(&info->super_copy);
1365 btrfs_set_super_bytes_used(&info->super_copy,
1366 super_used - num_bytes);
1367
1368 /* block accounting for root item */
1369 root_used = btrfs_root_used(&root->root_item);
1370 btrfs_set_root_used(&root->root_item,
1371 root_used - num_bytes);
1372 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
1373 num_to_del);
1374 if (ret) {
1375 return ret;
1376 }
1377 ret = update_block_group(trans, root, bytenr, num_bytes, 0,
1378 mark_free);
1379 BUG_ON(ret);
1380 }
1381 btrfs_free_path(path);
1382 finish_current_insert(trans, extent_root);
1383 return ret;
1384 }
1385
1386 /*
1387 * find all the blocks marked as pending in the radix tree and remove
1388 * them from the extent map
1389 */
1390 static int del_pending_extents(struct btrfs_trans_handle *trans, struct
1391 btrfs_root *extent_root)
1392 {
1393 int ret;
1394 int err = 0;
1395 u64 start;
1396 u64 end;
1397 struct extent_io_tree *pending_del;
1398 struct extent_io_tree *pinned_extents;
1399
1400 pending_del = &extent_root->fs_info->pending_del;
1401 pinned_extents = &extent_root->fs_info->pinned_extents;
1402
1403 while(1) {
1404 ret = find_first_extent_bit(pending_del, 0, &start, &end,
1405 EXTENT_LOCKED);
1406 if (ret)
1407 break;
1408 update_pinned_extents(extent_root, start, end + 1 - start, 1);
1409 clear_extent_bits(pending_del, start, end, EXTENT_LOCKED,
1410 GFP_NOFS);
1411 ret = __free_extent(trans, extent_root,
1412 start, end + 1 - start,
1413 extent_root->root_key.objectid,
1414 0, 0, 0, 0, 0);
1415 if (ret)
1416 err = ret;
1417 }
1418 return err;
1419 }
1420
1421 /*
1422 * remove an extent from the root, returns 0 on success
1423 */
1424 int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
1425 *root, u64 bytenr, u64 num_bytes,
1426 u64 root_objectid, u64 ref_generation,
1427 u64 owner_objectid, u64 owner_offset, int pin)
1428 {
1429 struct btrfs_root *extent_root = root->fs_info->extent_root;
1430 int pending_ret;
1431 int ret;
1432
1433 WARN_ON(num_bytes < root->sectorsize);
1434 if (!root->ref_cows)
1435 ref_generation = 0;
1436
1437 if (root == extent_root) {
1438 pin_down_bytes(root, bytenr, num_bytes, 1);
1439 return 0;
1440 }
1441 ret = __free_extent(trans, root, bytenr, num_bytes, root_objectid,
1442 ref_generation, owner_objectid, owner_offset,
1443 pin, pin == 0);
1444 pending_ret = del_pending_extents(trans, root->fs_info->extent_root);
1445 return ret ? ret : pending_ret;
1446 }
1447
1448 static u64 stripe_align(struct btrfs_root *root, u64 val)
1449 {
1450 u64 mask = ((u64)root->stripesize - 1);
1451 u64 ret = (val + mask) & ~mask;
1452 return ret;
1453 }
1454
1455 /*
1456 * walks the btree of allocated extents and find a hole of a given size.
1457 * The key ins is changed to record the hole:
1458 * ins->objectid == block start
1459 * ins->flags = BTRFS_EXTENT_ITEM_KEY
1460 * ins->offset == number of blocks
1461 * Any available blocks before search_start are skipped.
1462 */
1463 static int noinline find_free_extent(struct btrfs_trans_handle *trans,
1464 struct btrfs_root *orig_root,
1465 u64 num_bytes, u64 empty_size,
1466 u64 search_start, u64 search_end,
1467 u64 hint_byte, struct btrfs_key *ins,
1468 u64 exclude_start, u64 exclude_nr,
1469 int data)
1470 {
1471 int ret;
1472 u64 orig_search_start = search_start;
1473 struct btrfs_root * root = orig_root->fs_info->extent_root;
1474 struct btrfs_fs_info *info = root->fs_info;
1475 u64 total_needed = num_bytes;
1476 u64 *last_ptr = NULL;
1477 struct btrfs_block_group_cache *block_group;
1478 int full_scan = 0;
1479 int wrapped = 0;
1480 int empty_cluster = 2 * 1024 * 1024;
1481
1482 WARN_ON(num_bytes < root->sectorsize);
1483 btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
1484
1485 if (data & BTRFS_BLOCK_GROUP_METADATA) {
1486 last_ptr = &root->fs_info->last_alloc;
1487 }
1488
1489 if ((data & BTRFS_BLOCK_GROUP_DATA) && btrfs_test_opt(root, SSD)) {
1490 last_ptr = &root->fs_info->last_data_alloc;
1491 }
1492
1493 if (last_ptr) {
1494 if (*last_ptr)
1495 hint_byte = *last_ptr;
1496 else {
1497 empty_size += empty_cluster;
1498 }
1499 }
1500
1501 if (search_end == (u64)-1)
1502 search_end = btrfs_super_total_bytes(&info->super_copy);
1503
1504 if (hint_byte) {
1505 block_group = btrfs_lookup_block_group(info, hint_byte);
1506 if (!block_group)
1507 hint_byte = search_start;
1508 block_group = btrfs_find_block_group(root, block_group,
1509 hint_byte, data, 1);
1510 if (last_ptr && *last_ptr == 0 && block_group)
1511 hint_byte = block_group->key.objectid;
1512 } else {
1513 block_group = btrfs_find_block_group(root,
1514 trans->block_group,
1515 search_start, data, 1);
1516 }
1517 search_start = max(search_start, hint_byte);
1518
1519 total_needed += empty_size;
1520
1521 check_failed:
1522 if (!block_group) {
1523 block_group = btrfs_lookup_block_group(info, search_start);
1524 if (!block_group)
1525 block_group = btrfs_lookup_block_group(info,
1526 orig_search_start);
1527 }
1528 ret = find_search_start(root, &block_group, &search_start,
1529 total_needed, data);
1530 if (ret == -ENOSPC && last_ptr && *last_ptr) {
1531 *last_ptr = 0;
1532 block_group = btrfs_lookup_block_group(info,
1533 orig_search_start);
1534 search_start = orig_search_start;
1535 ret = find_search_start(root, &block_group, &search_start,
1536 total_needed, data);
1537 }
1538 if (ret == -ENOSPC)
1539 goto enospc;
1540 if (ret)
1541 goto error;
1542
1543 if (last_ptr && *last_ptr && search_start != *last_ptr) {
1544 *last_ptr = 0;
1545 if (!empty_size) {
1546 empty_size += empty_cluster;
1547 total_needed += empty_size;
1548 }
1549 block_group = btrfs_lookup_block_group(info,
1550 orig_search_start);
1551 search_start = orig_search_start;
1552 ret = find_search_start(root, &block_group,
1553 &search_start, total_needed, data);
1554 if (ret == -ENOSPC)
1555 goto enospc;
1556 if (ret)
1557 goto error;
1558 }
1559
1560 search_start = stripe_align(root, search_start);
1561 ins->objectid = search_start;
1562 ins->offset = num_bytes;
1563
1564 if (ins->objectid + num_bytes >= search_end)
1565 goto enospc;
1566
1567 if (ins->objectid + num_bytes >
1568 block_group->key.objectid + block_group->key.offset) {
1569 search_start = block_group->key.objectid +
1570 block_group->key.offset;
1571 goto new_group;
1572 }
1573
1574 if (test_range_bit(&info->extent_ins, ins->objectid,
1575 ins->objectid + num_bytes -1, EXTENT_LOCKED, 0)) {
1576 search_start = ins->objectid + num_bytes;
1577 goto new_group;
1578 }
1579
1580 if (test_range_bit(&info->pinned_extents, ins->objectid,
1581 ins->objectid + num_bytes -1, EXTENT_DIRTY, 0)) {
1582 search_start = ins->objectid + num_bytes;
1583 goto new_group;
1584 }
1585
1586 if (exclude_nr > 0 && (ins->objectid + num_bytes > exclude_start &&
1587 ins->objectid < exclude_start + exclude_nr)) {
1588 search_start = exclude_start + exclude_nr;
1589 goto new_group;
1590 }
1591
1592 if (!(data & BTRFS_BLOCK_GROUP_DATA)) {
1593 block_group = btrfs_lookup_block_group(info, ins->objectid);
1594 if (block_group)
1595 trans->block_group = block_group;
1596 }
1597 ins->offset = num_bytes;
1598 if (last_ptr) {
1599 *last_ptr = ins->objectid + ins->offset;
1600 if (*last_ptr ==
1601 btrfs_super_total_bytes(&root->fs_info->super_copy)) {
1602 *last_ptr = 0;
1603 }
1604 }
1605 return 0;
1606
1607 new_group:
1608 if (search_start + num_bytes >= search_end) {
1609 enospc:
1610 search_start = orig_search_start;
1611 if (full_scan) {
1612 ret = -ENOSPC;
1613 goto error;
1614 }
1615 if (wrapped) {
1616 if (!full_scan)
1617 total_needed -= empty_size;
1618 full_scan = 1;
1619 } else
1620 wrapped = 1;
1621 }
1622 block_group = btrfs_lookup_block_group(info, search_start);
1623 cond_resched();
1624 block_group = btrfs_find_block_group(root, block_group,
1625 search_start, data, 0);
1626 goto check_failed;
1627
1628 error:
1629 return ret;
1630 }
1631 /*
1632 * finds a free extent and does all the dirty work required for allocation
1633 * returns the key for the extent through ins, and a tree buffer for
1634 * the first block of the extent through buf.
1635 *
1636 * returns 0 if everything worked, non-zero otherwise.
1637 */
1638 int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
1639 struct btrfs_root *root,
1640 u64 num_bytes, u64 root_objectid, u64 ref_generation,
1641 u64 owner, u64 owner_offset,
1642 u64 empty_size, u64 hint_byte,
1643 u64 search_end, struct btrfs_key *ins, int data)
1644 {
1645 int ret;
1646 int pending_ret;
1647 u64 super_used;
1648 u64 root_used;
1649 u64 search_start = 0;
1650 u64 new_hint;
1651 u32 sizes[2];
1652 struct btrfs_fs_info *info = root->fs_info;
1653 struct btrfs_root *extent_root = info->extent_root;
1654 struct btrfs_extent_item *extent_item;
1655 struct btrfs_extent_ref *ref;
1656 struct btrfs_path *path;
1657 struct btrfs_key keys[2];
1658
1659 if (data) {
1660 data = BTRFS_BLOCK_GROUP_DATA;
1661 } else if (root == root->fs_info->chunk_root) {
1662 data = BTRFS_BLOCK_GROUP_SYSTEM;
1663 } else {
1664 data = BTRFS_BLOCK_GROUP_METADATA;
1665 }
1666
1667 if (root->ref_cows) {
1668 if (data != BTRFS_BLOCK_GROUP_METADATA) {
1669 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
1670 2 * 1024 * 1024,
1671 BTRFS_BLOCK_GROUP_METADATA);
1672 BUG_ON(ret);
1673 }
1674 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
1675 num_bytes + 2 * 1024 * 1024, data);
1676 BUG_ON(ret);
1677 }
1678
1679 new_hint = max(hint_byte, root->fs_info->alloc_start);
1680 if (new_hint < btrfs_super_total_bytes(&info->super_copy))
1681 hint_byte = new_hint;
1682
1683 WARN_ON(num_bytes < root->sectorsize);
1684 ret = find_free_extent(trans, root, num_bytes, empty_size,
1685 search_start, search_end, hint_byte, ins,
1686 trans->alloc_exclude_start,
1687 trans->alloc_exclude_nr, data);
1688 BUG_ON(ret);
1689 if (ret)
1690 return ret;
1691
1692 /* block accounting for super block */
1693 super_used = btrfs_super_bytes_used(&info->super_copy);
1694 btrfs_set_super_bytes_used(&info->super_copy, super_used + num_bytes);
1695
1696 /* block accounting for root item */
1697 root_used = btrfs_root_used(&root->root_item);
1698 btrfs_set_root_used(&root->root_item, root_used + num_bytes);
1699
1700 clear_extent_dirty(&root->fs_info->free_space_cache,
1701 ins->objectid, ins->objectid + ins->offset - 1,
1702 GFP_NOFS);
1703
1704 if (root == extent_root) {
1705 set_extent_bits(&root->fs_info->extent_ins, ins->objectid,
1706 ins->objectid + ins->offset - 1,
1707 EXTENT_LOCKED, GFP_NOFS);
1708 goto update_block;
1709 }
1710
1711 WARN_ON(trans->alloc_exclude_nr);
1712 trans->alloc_exclude_start = ins->objectid;
1713 trans->alloc_exclude_nr = ins->offset;
1714
1715 memcpy(&keys[0], ins, sizeof(*ins));
1716 keys[1].offset = hash_extent_ref(root_objectid, ref_generation,
1717 owner, owner_offset);
1718 keys[1].objectid = ins->objectid;
1719 keys[1].type = BTRFS_EXTENT_REF_KEY;
1720 sizes[0] = sizeof(*extent_item);
1721 sizes[1] = sizeof(*ref);
1722
1723 path = btrfs_alloc_path();
1724 BUG_ON(!path);
1725
1726 ret = btrfs_insert_empty_items(trans, extent_root, path, keys,
1727 sizes, 2);
1728
1729 BUG_ON(ret);
1730 extent_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
1731 struct btrfs_extent_item);
1732 btrfs_set_extent_refs(path->nodes[0], extent_item, 1);
1733 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
1734 struct btrfs_extent_ref);
1735
1736 btrfs_set_ref_root(path->nodes[0], ref, root_objectid);
1737 btrfs_set_ref_generation(path->nodes[0], ref, ref_generation);
1738 btrfs_set_ref_objectid(path->nodes[0], ref, owner);
1739 btrfs_set_ref_offset(path->nodes[0], ref, owner_offset);
1740
1741 btrfs_mark_buffer_dirty(path->nodes[0]);
1742
1743 trans->alloc_exclude_start = 0;
1744 trans->alloc_exclude_nr = 0;
1745 btrfs_free_path(path);
1746 finish_current_insert(trans, extent_root);
1747 pending_ret = del_pending_extents(trans, extent_root);
1748
1749 if (ret) {
1750 return ret;
1751 }
1752 if (pending_ret) {
1753 return pending_ret;
1754 }
1755
1756 update_block:
1757 ret = update_block_group(trans, root, ins->objectid, ins->offset, 1, 0);
1758 if (ret) {
1759 printk("update block group failed for %Lu %Lu\n",
1760 ins->objectid, ins->offset);
1761 BUG();
1762 }
1763 return 0;
1764 }
1765
1766 /*
1767 * helper function to allocate a block for a given tree
1768 * returns the tree buffer or NULL.
1769 */
1770 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
1771 struct btrfs_root *root,
1772 u32 blocksize,
1773 u64 root_objectid, u64 hint,
1774 u64 empty_size)
1775 {
1776 u64 ref_generation;
1777
1778 if (root->ref_cows)
1779 ref_generation = trans->transid;
1780 else
1781 ref_generation = 0;
1782
1783
1784 return __btrfs_alloc_free_block(trans, root, blocksize, root_objectid,
1785 ref_generation, 0, 0, hint, empty_size);
1786 }
1787
1788 /*
1789 * helper function to allocate a block for a given tree
1790 * returns the tree buffer or NULL.
1791 */
1792 struct extent_buffer *__btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
1793 struct btrfs_root *root,
1794 u32 blocksize,
1795 u64 root_objectid,
1796 u64 ref_generation,
1797 u64 first_objectid,
1798 int level,
1799 u64 hint,
1800 u64 empty_size)
1801 {
1802 struct btrfs_key ins;
1803 int ret;
1804 struct extent_buffer *buf;
1805
1806 ret = btrfs_alloc_extent(trans, root, blocksize,
1807 root_objectid, ref_generation,
1808 level, first_objectid, empty_size, hint,
1809 (u64)-1, &ins, 0);
1810 if (ret) {
1811 BUG_ON(ret > 0);
1812 return ERR_PTR(ret);
1813 }
1814 buf = btrfs_find_create_tree_block(root, ins.objectid, blocksize);
1815 if (!buf) {
1816 btrfs_free_extent(trans, root, ins.objectid, blocksize,
1817 root->root_key.objectid, ref_generation,
1818 0, 0, 0);
1819 return ERR_PTR(-ENOMEM);
1820 }
1821 btrfs_set_header_generation(buf, trans->transid);
1822 clean_tree_block(trans, root, buf);
1823 wait_on_tree_block_writeback(root, buf);
1824 btrfs_set_buffer_uptodate(buf);
1825
1826 if (PageDirty(buf->first_page)) {
1827 printk("page %lu dirty\n", buf->first_page->index);
1828 WARN_ON(1);
1829 }
1830
1831 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
1832 buf->start + buf->len - 1, GFP_NOFS);
1833 set_extent_bits(&BTRFS_I(root->fs_info->btree_inode)->io_tree,
1834 buf->start, buf->start + buf->len - 1,
1835 EXTENT_CSUM, GFP_NOFS);
1836 buf->flags |= EXTENT_CSUM;
1837 if (!btrfs_test_opt(root, SSD))
1838 btrfs_set_buffer_defrag(buf);
1839 trans->blocks_used++;
1840 return buf;
1841 }
1842
1843 static int noinline drop_leaf_ref(struct btrfs_trans_handle *trans,
1844 struct btrfs_root *root,
1845 struct extent_buffer *leaf)
1846 {
1847 u64 leaf_owner;
1848 u64 leaf_generation;
1849 struct btrfs_key key;
1850 struct btrfs_file_extent_item *fi;
1851 int i;
1852 int nritems;
1853 int ret;
1854
1855 BUG_ON(!btrfs_is_leaf(leaf));
1856 nritems = btrfs_header_nritems(leaf);
1857 leaf_owner = btrfs_header_owner(leaf);
1858 leaf_generation = btrfs_header_generation(leaf);
1859
1860 for (i = 0; i < nritems; i++) {
1861 u64 disk_bytenr;
1862
1863 btrfs_item_key_to_cpu(leaf, &key, i);
1864 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
1865 continue;
1866 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
1867 if (btrfs_file_extent_type(leaf, fi) ==
1868 BTRFS_FILE_EXTENT_INLINE)
1869 continue;
1870 /*
1871 * FIXME make sure to insert a trans record that
1872 * repeats the snapshot del on crash
1873 */
1874 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1875 if (disk_bytenr == 0)
1876 continue;
1877 ret = btrfs_free_extent(trans, root, disk_bytenr,
1878 btrfs_file_extent_disk_num_bytes(leaf, fi),
1879 leaf_owner, leaf_generation,
1880 key.objectid, key.offset, 0);
1881 BUG_ON(ret);
1882 }
1883 return 0;
1884 }
1885
1886 static void noinline reada_walk_down(struct btrfs_root *root,
1887 struct extent_buffer *node,
1888 int slot)
1889 {
1890 u64 bytenr;
1891 u64 last = 0;
1892 u32 nritems;
1893 u32 refs;
1894 u32 blocksize;
1895 int ret;
1896 int i;
1897 int level;
1898 int skipped = 0;
1899
1900 nritems = btrfs_header_nritems(node);
1901 level = btrfs_header_level(node);
1902 if (level)
1903 return;
1904
1905 for (i = slot; i < nritems && skipped < 32; i++) {
1906 bytenr = btrfs_node_blockptr(node, i);
1907 if (last && ((bytenr > last && bytenr - last > 32 * 1024) ||
1908 (last > bytenr && last - bytenr > 32 * 1024))) {
1909 skipped++;
1910 continue;
1911 }
1912 blocksize = btrfs_level_size(root, level - 1);
1913 if (i != slot) {
1914 ret = lookup_extent_ref(NULL, root, bytenr,
1915 blocksize, &refs);
1916 BUG_ON(ret);
1917 if (refs != 1) {
1918 skipped++;
1919 continue;
1920 }
1921 }
1922 mutex_unlock(&root->fs_info->fs_mutex);
1923 ret = readahead_tree_block(root, bytenr, blocksize);
1924 last = bytenr + blocksize;
1925 cond_resched();
1926 mutex_lock(&root->fs_info->fs_mutex);
1927 if (ret)
1928 break;
1929 }
1930 }
1931
1932 /*
1933 * helper function for drop_snapshot, this walks down the tree dropping ref
1934 * counts as it goes.
1935 */
1936 static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
1937 struct btrfs_root *root,
1938 struct btrfs_path *path, int *level)
1939 {
1940 u64 root_owner;
1941 u64 root_gen;
1942 u64 bytenr;
1943 struct extent_buffer *next;
1944 struct extent_buffer *cur;
1945 struct extent_buffer *parent;
1946 u32 blocksize;
1947 int ret;
1948 u32 refs;
1949
1950 WARN_ON(*level < 0);
1951 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1952 ret = lookup_extent_ref(trans, root,
1953 path->nodes[*level]->start,
1954 path->nodes[*level]->len, &refs);
1955 BUG_ON(ret);
1956 if (refs > 1)
1957 goto out;
1958
1959 /*
1960 * walk down to the last node level and free all the leaves
1961 */
1962 while(*level >= 0) {
1963 WARN_ON(*level < 0);
1964 WARN_ON(*level >= BTRFS_MAX_LEVEL);
1965 cur = path->nodes[*level];
1966
1967 if (btrfs_header_level(cur) != *level)
1968 WARN_ON(1);
1969
1970 if (path->slots[*level] >=
1971 btrfs_header_nritems(cur))
1972 break;
1973 if (*level == 0) {
1974 ret = drop_leaf_ref(trans, root, cur);
1975 BUG_ON(ret);
1976 break;
1977 }
1978 bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
1979 blocksize = btrfs_level_size(root, *level - 1);
1980 ret = lookup_extent_ref(trans, root, bytenr, blocksize, &refs);
1981 BUG_ON(ret);
1982 if (refs != 1) {
1983 parent = path->nodes[*level];
1984 root_owner = btrfs_header_owner(parent);
1985 root_gen = btrfs_header_generation(parent);
1986 path->slots[*level]++;
1987 ret = btrfs_free_extent(trans, root, bytenr,
1988 blocksize, root_owner,
1989 root_gen, 0, 0, 1);
1990 BUG_ON(ret);
1991 continue;
1992 }
1993 next = btrfs_find_tree_block(root, bytenr, blocksize);
1994 if (!next || !btrfs_buffer_uptodate(next)) {
1995 free_extent_buffer(next);
1996 reada_walk_down(root, cur, path->slots[*level]);
1997 mutex_unlock(&root->fs_info->fs_mutex);
1998 next = read_tree_block(root, bytenr, blocksize);
1999 mutex_lock(&root->fs_info->fs_mutex);
2000
2001 /* we dropped the lock, check one more time */
2002 ret = lookup_extent_ref(trans, root, bytenr,
2003 blocksize, &refs);
2004 BUG_ON(ret);
2005 if (refs != 1) {
2006 parent = path->nodes[*level];
2007 root_owner = btrfs_header_owner(parent);
2008 root_gen = btrfs_header_generation(parent);
2009
2010 path->slots[*level]++;
2011 free_extent_buffer(next);
2012 ret = btrfs_free_extent(trans, root, bytenr,
2013 blocksize,
2014 root_owner,
2015 root_gen, 0, 0, 1);
2016 BUG_ON(ret);
2017 continue;
2018 }
2019 }
2020 WARN_ON(*level <= 0);
2021 if (path->nodes[*level-1])
2022 free_extent_buffer(path->nodes[*level-1]);
2023 path->nodes[*level-1] = next;
2024 *level = btrfs_header_level(next);
2025 path->slots[*level] = 0;
2026 }
2027 out:
2028 WARN_ON(*level < 0);
2029 WARN_ON(*level >= BTRFS_MAX_LEVEL);
2030
2031 if (path->nodes[*level] == root->node) {
2032 root_owner = root->root_key.objectid;
2033 parent = path->nodes[*level];
2034 } else {
2035 parent = path->nodes[*level + 1];
2036 root_owner = btrfs_header_owner(parent);
2037 }
2038
2039 root_gen = btrfs_header_generation(parent);
2040 ret = btrfs_free_extent(trans, root, path->nodes[*level]->start,
2041 path->nodes[*level]->len,
2042 root_owner, root_gen, 0, 0, 1);
2043 free_extent_buffer(path->nodes[*level]);
2044 path->nodes[*level] = NULL;
2045 *level += 1;
2046 BUG_ON(ret);
2047 return 0;
2048 }
2049
2050 /*
2051 * helper for dropping snapshots. This walks back up the tree in the path
2052 * to find the first node higher up where we haven't yet gone through
2053 * all the slots
2054 */
2055 static int noinline walk_up_tree(struct btrfs_trans_handle *trans,
2056 struct btrfs_root *root,
2057 struct btrfs_path *path, int *level)
2058 {
2059 u64 root_owner;
2060 u64 root_gen;
2061 struct btrfs_root_item *root_item = &root->root_item;
2062 int i;
2063 int slot;
2064 int ret;
2065
2066 for(i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
2067 slot = path->slots[i];
2068 if (slot < btrfs_header_nritems(path->nodes[i]) - 1) {
2069 struct extent_buffer *node;
2070 struct btrfs_disk_key disk_key;
2071 node = path->nodes[i];
2072 path->slots[i]++;
2073 *level = i;
2074 WARN_ON(*level == 0);
2075 btrfs_node_key(node, &disk_key, path->slots[i]);
2076 memcpy(&root_item->drop_progress,
2077 &disk_key, sizeof(disk_key));
2078 root_item->drop_level = i;
2079 return 0;
2080 } else {
2081 if (path->nodes[*level] == root->node) {
2082 root_owner = root->root_key.objectid;
2083 root_gen =
2084 btrfs_header_generation(path->nodes[*level]);
2085 } else {
2086 struct extent_buffer *node;
2087 node = path->nodes[*level + 1];
2088 root_owner = btrfs_header_owner(node);
2089 root_gen = btrfs_header_generation(node);
2090 }
2091 ret = btrfs_free_extent(trans, root,
2092 path->nodes[*level]->start,
2093 path->nodes[*level]->len,
2094 root_owner, root_gen, 0, 0, 1);
2095 BUG_ON(ret);
2096 free_extent_buffer(path->nodes[*level]);
2097 path->nodes[*level] = NULL;
2098 *level = i + 1;
2099 }
2100 }
2101 return 1;
2102 }
2103
2104 /*
2105 * drop the reference count on the tree rooted at 'snap'. This traverses
2106 * the tree freeing any blocks that have a ref count of zero after being
2107 * decremented.
2108 */
2109 int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root
2110 *root)
2111 {
2112 int ret = 0;
2113 int wret;
2114 int level;
2115 struct btrfs_path *path;
2116 int i;
2117 int orig_level;
2118 struct btrfs_root_item *root_item = &root->root_item;
2119
2120 path = btrfs_alloc_path();
2121 BUG_ON(!path);
2122
2123 level = btrfs_header_level(root->node);
2124 orig_level = level;
2125 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
2126 path->nodes[level] = root->node;
2127 extent_buffer_get(root->node);
2128 path->slots[level] = 0;
2129 } else {
2130 struct btrfs_key key;
2131 struct btrfs_disk_key found_key;
2132 struct extent_buffer *node;
2133
2134 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
2135 level = root_item->drop_level;
2136 path->lowest_level = level;
2137 wret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2138 if (wret < 0) {
2139 ret = wret;
2140 goto out;
2141 }
2142 node = path->nodes[level];
2143 btrfs_node_key(node, &found_key, path->slots[level]);
2144 WARN_ON(memcmp(&found_key, &root_item->drop_progress,
2145 sizeof(found_key)));
2146 }
2147 while(1) {
2148 wret = walk_down_tree(trans, root, path, &level);
2149 if (wret > 0)
2150 break;
2151 if (wret < 0)
2152 ret = wret;
2153
2154 wret = walk_up_tree(trans, root, path, &level);
2155 if (wret > 0)
2156 break;
2157 if (wret < 0)
2158 ret = wret;
2159 ret = -EAGAIN;
2160 break;
2161 }
2162 for (i = 0; i <= orig_level; i++) {
2163 if (path->nodes[i]) {
2164 free_extent_buffer(path->nodes[i]);
2165 path->nodes[i] = NULL;
2166 }
2167 }
2168 out:
2169 btrfs_free_path(path);
2170 return ret;
2171 }
2172
2173 int btrfs_free_block_groups(struct btrfs_fs_info *info)
2174 {
2175 u64 start;
2176 u64 end;
2177 u64 ptr;
2178 int ret;
2179 while(1) {
2180 ret = find_first_extent_bit(&info->block_group_cache, 0,
2181 &start, &end, (unsigned int)-1);
2182 if (ret)
2183 break;
2184 ret = get_state_private(&info->block_group_cache, start, &ptr);
2185 if (!ret)
2186 kfree((void *)(unsigned long)ptr);
2187 clear_extent_bits(&info->block_group_cache, start,
2188 end, (unsigned int)-1, GFP_NOFS);
2189 }
2190 while(1) {
2191 ret = find_first_extent_bit(&info->free_space_cache, 0,
2192 &start, &end, EXTENT_DIRTY);
2193 if (ret)
2194 break;
2195 clear_extent_dirty(&info->free_space_cache, start,
2196 end, GFP_NOFS);
2197 }
2198 return 0;
2199 }
2200
2201 static int noinline relocate_inode_pages(struct inode *inode, u64 start,
2202 u64 len)
2203 {
2204 u64 page_start;
2205 u64 page_end;
2206 u64 delalloc_start;
2207 u64 existing_delalloc;
2208 unsigned long last_index;
2209 unsigned long i;
2210 struct page *page;
2211 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2212 struct file_ra_state *ra;
2213
2214 ra = kzalloc(sizeof(*ra), GFP_NOFS);
2215
2216 mutex_lock(&inode->i_mutex);
2217 i = start >> PAGE_CACHE_SHIFT;
2218 last_index = (start + len - 1) >> PAGE_CACHE_SHIFT;
2219
2220 file_ra_state_init(ra, inode->i_mapping);
2221 btrfs_force_ra(inode->i_mapping, ra, NULL, i, last_index);
2222 kfree(ra);
2223
2224 for (; i <= last_index; i++) {
2225 page = grab_cache_page(inode->i_mapping, i);
2226 if (!page)
2227 goto out_unlock;
2228 if (!PageUptodate(page)) {
2229 btrfs_readpage(NULL, page);
2230 lock_page(page);
2231 if (!PageUptodate(page)) {
2232 unlock_page(page);
2233 page_cache_release(page);
2234 goto out_unlock;
2235 }
2236 }
2237 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
2238 page_end = page_start + PAGE_CACHE_SIZE - 1;
2239
2240 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
2241
2242 delalloc_start = page_start;
2243 existing_delalloc = count_range_bits(io_tree,
2244 &delalloc_start, page_end,
2245 PAGE_CACHE_SIZE, EXTENT_DELALLOC);
2246
2247 set_extent_delalloc(io_tree, page_start,
2248 page_end, GFP_NOFS);
2249
2250 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
2251 set_page_dirty(page);
2252 unlock_page(page);
2253 page_cache_release(page);
2254 }
2255
2256 out_unlock:
2257 mutex_unlock(&inode->i_mutex);
2258 return 0;
2259 }
2260
2261 /*
2262 * note, this releases the path
2263 */
2264 static int noinline relocate_one_reference(struct btrfs_root *extent_root,
2265 struct btrfs_path *path,
2266 struct btrfs_key *extent_key)
2267 {
2268 struct inode *inode;
2269 struct btrfs_root *found_root;
2270 struct btrfs_key *root_location;
2271 struct btrfs_extent_ref *ref;
2272 u64 ref_root;
2273 u64 ref_gen;
2274 u64 ref_objectid;
2275 u64 ref_offset;
2276 int ret;
2277
2278 ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
2279 struct btrfs_extent_ref);
2280 ref_root = btrfs_ref_root(path->nodes[0], ref);
2281 ref_gen = btrfs_ref_generation(path->nodes[0], ref);
2282 ref_objectid = btrfs_ref_objectid(path->nodes[0], ref);
2283 ref_offset = btrfs_ref_offset(path->nodes[0], ref);
2284 btrfs_release_path(extent_root, path);
2285
2286 root_location = kmalloc(sizeof(*root_location), GFP_NOFS);
2287 root_location->objectid = ref_root;
2288 if (ref_gen == 0)
2289 root_location->offset = 0;
2290 else
2291 root_location->offset = (u64)-1;
2292 root_location->type = BTRFS_ROOT_ITEM_KEY;
2293
2294 found_root = btrfs_read_fs_root_no_name(extent_root->fs_info,
2295 root_location);
2296 BUG_ON(!found_root);
2297 kfree(root_location);
2298
2299 if (ref_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
2300 mutex_unlock(&extent_root->fs_info->fs_mutex);
2301 inode = btrfs_iget_locked(extent_root->fs_info->sb,
2302 ref_objectid, found_root);
2303 if (inode->i_state & I_NEW) {
2304 /* the inode and parent dir are two different roots */
2305 BTRFS_I(inode)->root = found_root;
2306 BTRFS_I(inode)->location.objectid = ref_objectid;
2307 BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY;
2308 BTRFS_I(inode)->location.offset = 0;
2309 btrfs_read_locked_inode(inode);
2310 unlock_new_inode(inode);
2311
2312 }
2313 /* this can happen if the reference is not against
2314 * the latest version of the tree root
2315 */
2316 if (is_bad_inode(inode)) {
2317 mutex_lock(&extent_root->fs_info->fs_mutex);
2318 goto out;
2319 }
2320 relocate_inode_pages(inode, ref_offset, extent_key->offset);
2321 /* FIXME, data=ordered will help get rid of this */
2322 filemap_fdatawrite(inode->i_mapping);
2323 iput(inode);
2324 mutex_lock(&extent_root->fs_info->fs_mutex);
2325 } else {
2326 struct btrfs_trans_handle *trans;
2327 struct btrfs_key found_key;
2328 struct extent_buffer *eb;
2329 int level;
2330 int i;
2331
2332 trans = btrfs_start_transaction(found_root, 1);
2333 eb = read_tree_block(found_root, extent_key->objectid,
2334 extent_key->offset);
2335 level = btrfs_header_level(eb);
2336
2337 if (level == 0)
2338 btrfs_item_key_to_cpu(eb, &found_key, 0);
2339 else
2340 btrfs_node_key_to_cpu(eb, &found_key, 0);
2341
2342 free_extent_buffer(eb);
2343
2344 path->lowest_level = level;
2345 path->reada = 2;
2346 ret = btrfs_search_slot(trans, found_root, &found_key, path,
2347 0, 1);
2348 path->lowest_level = 0;
2349 for (i = level; i < BTRFS_MAX_LEVEL; i++) {
2350 if (!path->nodes[i])
2351 break;
2352 free_extent_buffer(path->nodes[i]);
2353 path->nodes[i] = NULL;
2354 }
2355 btrfs_release_path(found_root, path);
2356 btrfs_end_transaction(trans, found_root);
2357 }
2358
2359 out:
2360 return 0;
2361 }
2362
2363 static int noinline relocate_one_extent(struct btrfs_root *extent_root,
2364 struct btrfs_path *path,
2365 struct btrfs_key *extent_key)
2366 {
2367 struct btrfs_key key;
2368 struct btrfs_key found_key;
2369 struct extent_buffer *leaf;
2370 u32 nritems;
2371 u32 item_size;
2372 int ret = 0;
2373
2374 key.objectid = extent_key->objectid;
2375 key.type = BTRFS_EXTENT_REF_KEY;
2376 key.offset = 0;
2377
2378 while(1) {
2379 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
2380
2381 if (ret < 0)
2382 goto out;
2383
2384 ret = 0;
2385 leaf = path->nodes[0];
2386 nritems = btrfs_header_nritems(leaf);
2387 if (path->slots[0] == nritems)
2388 goto out;
2389
2390 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2391 if (found_key.objectid != extent_key->objectid)
2392 break;
2393
2394 if (found_key.type != BTRFS_EXTENT_REF_KEY)
2395 break;
2396
2397 key.offset = found_key.offset + 1;
2398 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2399
2400 ret = relocate_one_reference(extent_root, path, extent_key);
2401 if (ret)
2402 goto out;
2403 }
2404 ret = 0;
2405 out:
2406 btrfs_release_path(extent_root, path);
2407 return ret;
2408 }
2409
2410 int btrfs_shrink_extent_tree(struct btrfs_root *root, u64 new_size)
2411 {
2412 struct btrfs_trans_handle *trans;
2413 struct btrfs_root *tree_root = root->fs_info->tree_root;
2414 struct btrfs_path *path;
2415 u64 cur_byte;
2416 u64 total_found;
2417 struct btrfs_fs_info *info = root->fs_info;
2418 struct extent_io_tree *block_group_cache;
2419 struct btrfs_key key;
2420 struct btrfs_key found_key;
2421 struct extent_buffer *leaf;
2422 u32 nritems;
2423 int ret;
2424 int progress = 0;
2425
2426 btrfs_set_super_total_bytes(&info->super_copy, new_size);
2427 clear_extent_dirty(&info->free_space_cache, new_size, (u64)-1,
2428 GFP_NOFS);
2429 block_group_cache = &info->block_group_cache;
2430 path = btrfs_alloc_path();
2431 root = root->fs_info->extent_root;
2432 path->reada = 2;
2433
2434 again:
2435 total_found = 0;
2436 key.objectid = new_size;
2437 key.offset = 0;
2438 key.type = 0;
2439 cur_byte = key.objectid;
2440
2441 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2442 if (ret < 0)
2443 goto out;
2444
2445 ret = btrfs_previous_item(root, path, 0, BTRFS_EXTENT_ITEM_KEY);
2446 if (ret < 0)
2447 goto out;
2448 if (ret == 0) {
2449 leaf = path->nodes[0];
2450 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2451 if (found_key.objectid + found_key.offset > new_size) {
2452 cur_byte = found_key.objectid;
2453 key.objectid = cur_byte;
2454 }
2455 }
2456 btrfs_release_path(root, path);
2457
2458 while(1) {
2459 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2460 if (ret < 0)
2461 goto out;
2462
2463 leaf = path->nodes[0];
2464 nritems = btrfs_header_nritems(leaf);
2465 next:
2466 if (path->slots[0] >= nritems) {
2467 ret = btrfs_next_leaf(root, path);
2468 if (ret < 0)
2469 goto out;
2470 if (ret == 1) {
2471 ret = 0;
2472 break;
2473 }
2474 leaf = path->nodes[0];
2475 nritems = btrfs_header_nritems(leaf);
2476 }
2477
2478 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2479
2480 if (progress && need_resched()) {
2481 memcpy(&key, &found_key, sizeof(key));
2482 mutex_unlock(&root->fs_info->fs_mutex);
2483 cond_resched();
2484 mutex_lock(&root->fs_info->fs_mutex);
2485 btrfs_release_path(root, path);
2486 btrfs_search_slot(NULL, root, &key, path, 0, 0);
2487 progress = 0;
2488 goto next;
2489 }
2490 progress = 1;
2491
2492 if (btrfs_key_type(&found_key) != BTRFS_EXTENT_ITEM_KEY ||
2493 found_key.objectid + found_key.offset <= cur_byte) {
2494 path->slots[0]++;
2495 goto next;
2496 }
2497
2498 total_found++;
2499 cur_byte = found_key.objectid + found_key.offset;
2500 key.objectid = cur_byte;
2501 btrfs_release_path(root, path);
2502 ret = relocate_one_extent(root, path, &found_key);
2503 }
2504
2505 btrfs_release_path(root, path);
2506
2507 if (total_found > 0) {
2508 trans = btrfs_start_transaction(tree_root, 1);
2509 btrfs_commit_transaction(trans, tree_root);
2510
2511 mutex_unlock(&root->fs_info->fs_mutex);
2512 btrfs_clean_old_snapshots(tree_root);
2513 mutex_lock(&root->fs_info->fs_mutex);
2514
2515 trans = btrfs_start_transaction(tree_root, 1);
2516 btrfs_commit_transaction(trans, tree_root);
2517 goto again;
2518 }
2519
2520 trans = btrfs_start_transaction(root, 1);
2521 key.objectid = new_size;
2522 key.offset = 0;
2523 key.type = 0;
2524 while(1) {
2525 u64 ptr;
2526
2527 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2528 if (ret < 0)
2529 goto out;
2530
2531 leaf = path->nodes[0];
2532 nritems = btrfs_header_nritems(leaf);
2533 bg_next:
2534 if (path->slots[0] >= nritems) {
2535 ret = btrfs_next_leaf(root, path);
2536 if (ret < 0)
2537 break;
2538 if (ret == 1) {
2539 ret = 0;
2540 break;
2541 }
2542 leaf = path->nodes[0];
2543 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2544
2545 /*
2546 * btrfs_next_leaf doesn't cow buffers, we have to
2547 * do the search again
2548 */
2549 memcpy(&key, &found_key, sizeof(key));
2550 btrfs_release_path(root, path);
2551 goto resched_check;
2552 }
2553
2554 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2555 if (btrfs_key_type(&found_key) != BTRFS_BLOCK_GROUP_ITEM_KEY) {
2556 printk("shrinker found key %Lu %u %Lu\n",
2557 found_key.objectid, found_key.type,
2558 found_key.offset);
2559 path->slots[0]++;
2560 goto bg_next;
2561 }
2562 ret = get_state_private(&info->block_group_cache,
2563 found_key.objectid, &ptr);
2564 if (!ret)
2565 kfree((void *)(unsigned long)ptr);
2566
2567 clear_extent_bits(&info->block_group_cache, found_key.objectid,
2568 found_key.objectid + found_key.offset - 1,
2569 (unsigned int)-1, GFP_NOFS);
2570
2571 key.objectid = found_key.objectid + 1;
2572 btrfs_del_item(trans, root, path);
2573 btrfs_release_path(root, path);
2574 resched_check:
2575 if (need_resched()) {
2576 mutex_unlock(&root->fs_info->fs_mutex);
2577 cond_resched();
2578 mutex_lock(&root->fs_info->fs_mutex);
2579 }
2580 }
2581 clear_extent_dirty(&info->free_space_cache, new_size, (u64)-1,
2582 GFP_NOFS);
2583 btrfs_commit_transaction(trans, root);
2584 out:
2585 btrfs_free_path(path);
2586 return ret;
2587 }
2588
2589 int btrfs_grow_extent_tree(struct btrfs_trans_handle *trans,
2590 struct btrfs_root *root, u64 new_size)
2591 {
2592 btrfs_set_super_total_bytes(&root->fs_info->super_copy, new_size);
2593 return 0;
2594 }
2595
2596 int find_first_block_group(struct btrfs_root *root, struct btrfs_path *path,
2597 struct btrfs_key *key)
2598 {
2599 int ret;
2600 struct btrfs_key found_key;
2601 struct extent_buffer *leaf;
2602 int slot;
2603
2604 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
2605 if (ret < 0)
2606 return ret;
2607 while(1) {
2608 slot = path->slots[0];
2609 leaf = path->nodes[0];
2610 if (slot >= btrfs_header_nritems(leaf)) {
2611 ret = btrfs_next_leaf(root, path);
2612 if (ret == 0)
2613 continue;
2614 if (ret < 0)
2615 goto error;
2616 break;
2617 }
2618 btrfs_item_key_to_cpu(leaf, &found_key, slot);
2619
2620 if (found_key.objectid >= key->objectid &&
2621 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY)
2622 return 0;
2623 path->slots[0]++;
2624 }
2625 ret = -ENOENT;
2626 error:
2627 return ret;
2628 }
2629
2630 static int update_space_info(struct btrfs_fs_info *info, u64 flags,
2631 u64 total_bytes, u64 bytes_used,
2632 struct btrfs_space_info **space_info)
2633 {
2634 struct btrfs_space_info *found;
2635
2636 found = __find_space_info(info, flags);
2637 if (found) {
2638 found->total_bytes += total_bytes;
2639 found->bytes_used += bytes_used;
2640 WARN_ON(found->total_bytes < found->bytes_used);
2641 *space_info = found;
2642 return 0;
2643 }
2644 found = kmalloc(sizeof(*found), GFP_NOFS);
2645 if (!found)
2646 return -ENOMEM;
2647
2648 list_add(&found->list, &info->space_info);
2649 found->flags = flags;
2650 found->total_bytes = total_bytes;
2651 found->bytes_used = bytes_used;
2652 found->bytes_pinned = 0;
2653 found->full = 0;
2654 *space_info = found;
2655 return 0;
2656 }
2657
2658 int btrfs_read_block_groups(struct btrfs_root *root)
2659 {
2660 struct btrfs_path *path;
2661 int ret;
2662 int bit;
2663 struct btrfs_block_group_cache *cache;
2664 struct btrfs_fs_info *info = root->fs_info;
2665 struct btrfs_space_info *space_info;
2666 struct extent_io_tree *block_group_cache;
2667 struct btrfs_key key;
2668 struct btrfs_key found_key;
2669 struct extent_buffer *leaf;
2670
2671 block_group_cache = &info->block_group_cache;
2672 root = info->extent_root;
2673 key.objectid = 0;
2674 key.offset = 0;
2675 btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
2676 path = btrfs_alloc_path();
2677 if (!path)
2678 return -ENOMEM;
2679
2680 while(1) {
2681 ret = find_first_block_group(root, path, &key);
2682 if (ret > 0) {
2683 ret = 0;
2684 goto error;
2685 }
2686 if (ret != 0)
2687 goto error;
2688
2689 leaf = path->nodes[0];
2690 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2691 cache = kmalloc(sizeof(*cache), GFP_NOFS);
2692 if (!cache) {
2693 ret = -ENOMEM;
2694 break;
2695 }
2696
2697 read_extent_buffer(leaf, &cache->item,
2698 btrfs_item_ptr_offset(leaf, path->slots[0]),
2699 sizeof(cache->item));
2700 memcpy(&cache->key, &found_key, sizeof(found_key));
2701 cache->cached = 0;
2702 cache->pinned = 0;
2703
2704 key.objectid = found_key.objectid + found_key.offset;
2705 btrfs_release_path(root, path);
2706 cache->flags = btrfs_block_group_flags(&cache->item);
2707 bit = 0;
2708 if (cache->flags & BTRFS_BLOCK_GROUP_DATA) {
2709 bit = BLOCK_GROUP_DATA;
2710 } else if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM) {
2711 bit = BLOCK_GROUP_SYSTEM;
2712 } else if (cache->flags & BTRFS_BLOCK_GROUP_METADATA) {
2713 bit = BLOCK_GROUP_METADATA;
2714 }
2715
2716 ret = update_space_info(info, cache->flags, found_key.offset,
2717 btrfs_block_group_used(&cache->item),
2718 &space_info);
2719 BUG_ON(ret);
2720 cache->space_info = space_info;
2721
2722 /* use EXTENT_LOCKED to prevent merging */
2723 set_extent_bits(block_group_cache, found_key.objectid,
2724 found_key.objectid + found_key.offset - 1,
2725 bit | EXTENT_LOCKED, GFP_NOFS);
2726 set_state_private(block_group_cache, found_key.objectid,
2727 (unsigned long)cache);
2728
2729 if (key.objectid >=
2730 btrfs_super_total_bytes(&info->super_copy))
2731 break;
2732 }
2733 ret = 0;
2734 error:
2735 btrfs_free_path(path);
2736 return ret;
2737 }
2738
2739 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
2740 struct btrfs_root *root, u64 bytes_used,
2741 u64 type, u64 chunk_tree, u64 chunk_objectid,
2742 u64 size)
2743 {
2744 int ret;
2745 int bit = 0;
2746 struct btrfs_root *extent_root;
2747 struct btrfs_block_group_cache *cache;
2748 struct extent_io_tree *block_group_cache;
2749
2750 extent_root = root->fs_info->extent_root;
2751 block_group_cache = &root->fs_info->block_group_cache;
2752
2753 cache = kmalloc(sizeof(*cache), GFP_NOFS);
2754 BUG_ON(!cache);
2755 cache->key.objectid = chunk_objectid;
2756 cache->key.offset = size;
2757 cache->cached = 0;
2758 cache->pinned = 0;
2759 btrfs_set_key_type(&cache->key, BTRFS_BLOCK_GROUP_ITEM_KEY);
2760 memset(&cache->item, 0, sizeof(cache->item));
2761 btrfs_set_block_group_used(&cache->item, bytes_used);
2762 btrfs_set_block_group_chunk_tree(&cache->item, chunk_tree);
2763 btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
2764 cache->flags = type;
2765 btrfs_set_block_group_flags(&cache->item, type);
2766
2767 ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
2768 &cache->space_info);
2769 BUG_ON(ret);
2770
2771 if (type & BTRFS_BLOCK_GROUP_DATA) {
2772 bit = BLOCK_GROUP_DATA;
2773 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
2774 bit = BLOCK_GROUP_SYSTEM;
2775 } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
2776 bit = BLOCK_GROUP_METADATA;
2777 }
2778 set_extent_bits(block_group_cache, chunk_objectid,
2779 chunk_objectid + size - 1,
2780 bit | EXTENT_LOCKED, GFP_NOFS);
2781 set_state_private(block_group_cache, chunk_objectid,
2782 (unsigned long)cache);
2783
2784 ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
2785 sizeof(cache->item));
2786 BUG_ON(ret);
2787
2788 finish_current_insert(trans, extent_root);
2789 ret = del_pending_extents(trans, extent_root);
2790 BUG_ON(ret);
2791 return 0;
2792 }
Linux kernel - Deliverables
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