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Btrfs-progs: fi usage: free memory if realloc fails
[btrfs-progs-unstable/devel.git] / extent-tree.c
blob080f30d3ffabd918957218ca9113a706ef40eea9
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 <stdio.h>
20 #include <stdlib.h>
21 #include <stdint.h>
22 #include "kerncompat.h"
23 #include "radix-tree.h"
24 #include "ctree.h"
25 #include "disk-io.h"
26 #include "print-tree.h"
27 #include "transaction.h"
28 #include "crc32c.h"
29 #include "volumes.h"
30 #include "free-space-cache.h"
31 #include "math.h"
32 #include "utils.h"
33
34 #define PENDING_EXTENT_INSERT 0
35 #define PENDING_EXTENT_DELETE 1
36 #define PENDING_BACKREF_UPDATE 2
37
38 struct pending_extent_op {
39 int type;
40 u64 bytenr;
41 u64 num_bytes;
42 u64 flags;
43 struct btrfs_disk_key key;
44 int level;
45 };
46
47 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
48 struct btrfs_root *root,
49 u64 root_objectid, u64 generation,
50 u64 flags, struct btrfs_disk_key *key,
51 int level, struct btrfs_key *ins);
52 static int __free_extent(struct btrfs_trans_handle *trans,
53 struct btrfs_root *root,
54 u64 bytenr, u64 num_bytes, u64 parent,
55 u64 root_objectid, u64 owner_objectid,
56 u64 owner_offset, int refs_to_drop);
57 static int finish_current_insert(struct btrfs_trans_handle *trans, struct
58 btrfs_root *extent_root);
59 static int del_pending_extents(struct btrfs_trans_handle *trans, struct
60 btrfs_root *extent_root);
61 static struct btrfs_block_group_cache *
62 btrfs_find_block_group(struct btrfs_root *root, struct btrfs_block_group_cache
63 *hint, u64 search_start, int data, int owner);
64
65 static int remove_sb_from_cache(struct btrfs_root *root,
66 struct btrfs_block_group_cache *cache)
67 {
68 u64 bytenr;
69 u64 *logical;
70 int stripe_len;
71 int i, nr, ret;
72 struct extent_io_tree *free_space_cache;
73
74 free_space_cache = &root->fs_info->free_space_cache;
75 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
76 bytenr = btrfs_sb_offset(i);
77 ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
78 cache->key.objectid, bytenr, 0,
79 &logical, &nr, &stripe_len);
80 BUG_ON(ret);
81 while (nr--) {
82 clear_extent_dirty(free_space_cache, logical[nr],
83 logical[nr] + stripe_len - 1, GFP_NOFS);
84 }
85 kfree(logical);
86 }
87 return 0;
88 }
89
90 static int cache_block_group(struct btrfs_root *root,
91 struct btrfs_block_group_cache *block_group)
92 {
93 struct btrfs_path *path;
94 int ret;
95 struct btrfs_key key;
96 struct extent_buffer *leaf;
97 struct extent_io_tree *free_space_cache;
98 int slot;
99 u64 last;
100 u64 hole_size;
101
102 if (!block_group)
103 return 0;
104
105 root = root->fs_info->extent_root;
106 free_space_cache = &root->fs_info->free_space_cache;
107
108 if (block_group->cached)
109 return 0;
110
111 path = btrfs_alloc_path();
112 if (!path)
113 return -ENOMEM;
114
115 path->reada = 2;
116 last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
117 key.objectid = last;
118 key.offset = 0;
119 key.type = 0;
120
121 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
122 if (ret < 0)
123 goto err;
124
125 while(1) {
126 leaf = path->nodes[0];
127 slot = path->slots[0];
128 if (slot >= btrfs_header_nritems(leaf)) {
129 ret = btrfs_next_leaf(root, path);
130 if (ret < 0)
131 goto err;
132 if (ret == 0) {
133 continue;
134 } else {
135 break;
136 }
137 }
138 btrfs_item_key_to_cpu(leaf, &key, slot);
139 if (key.objectid < block_group->key.objectid) {
140 goto next;
141 }
142 if (key.objectid >= block_group->key.objectid +
143 block_group->key.offset) {
144 break;
145 }
146
147 if (key.type == BTRFS_EXTENT_ITEM_KEY ||
148 key.type == BTRFS_METADATA_ITEM_KEY) {
149 if (key.objectid > last) {
150 hole_size = key.objectid - last;
151 set_extent_dirty(free_space_cache, last,
152 last + hole_size - 1,
153 GFP_NOFS);
154 }
155 if (key.type == BTRFS_METADATA_ITEM_KEY)
156 last = key.objectid + root->leafsize;
157 else
158 last = key.objectid + key.offset;
159 }
160 next:
161 path->slots[0]++;
162 }
163
164 if (block_group->key.objectid +
165 block_group->key.offset > last) {
166 hole_size = block_group->key.objectid +
167 block_group->key.offset - last;
168 set_extent_dirty(free_space_cache, last,
169 last + hole_size - 1, GFP_NOFS);
170 }
171 remove_sb_from_cache(root, block_group);
172 block_group->cached = 1;
173 err:
174 btrfs_free_path(path);
175 return 0;
176 }
177
178 struct btrfs_block_group_cache *btrfs_lookup_first_block_group(struct
179 btrfs_fs_info *info,
180 u64 bytenr)
181 {
182 struct extent_io_tree *block_group_cache;
183 struct btrfs_block_group_cache *block_group = NULL;
184 u64 ptr;
185 u64 start;
186 u64 end;
187 int ret;
188
189 bytenr = max_t(u64, bytenr,
190 BTRFS_SUPER_INFO_OFFSET + BTRFS_SUPER_INFO_SIZE);
191 block_group_cache = &info->block_group_cache;
192 ret = find_first_extent_bit(block_group_cache,
193 bytenr, &start, &end,
194 BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA |
195 BLOCK_GROUP_SYSTEM);
196 if (ret) {
197 return NULL;
198 }
199 ret = get_state_private(block_group_cache, start, &ptr);
200 if (ret)
201 return NULL;
202
203 block_group = (struct btrfs_block_group_cache *)(unsigned long)ptr;
204 return block_group;
205 }
206
207 struct btrfs_block_group_cache *btrfs_lookup_block_group(struct
208 btrfs_fs_info *info,
209 u64 bytenr)
210 {
211 struct extent_io_tree *block_group_cache;
212 struct btrfs_block_group_cache *block_group = NULL;
213 u64 ptr;
214 u64 start;
215 u64 end;
216 int ret;
217
218 block_group_cache = &info->block_group_cache;
219 ret = find_first_extent_bit(block_group_cache,
220 bytenr, &start, &end,
221 BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA |
222 BLOCK_GROUP_SYSTEM);
223 if (ret) {
224 return NULL;
225 }
226 ret = get_state_private(block_group_cache, start, &ptr);
227 if (ret)
228 return NULL;
229
230 block_group = (struct btrfs_block_group_cache *)(unsigned long)ptr;
231 if (block_group->key.objectid <= bytenr && bytenr <
232 block_group->key.objectid + block_group->key.offset)
233 return block_group;
234 return NULL;
235 }
236
237 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
238 {
239 return (cache->flags & bits) == bits;
240 }
241
242 static int noinline find_search_start(struct btrfs_root *root,
243 struct btrfs_block_group_cache **cache_ret,
244 u64 *start_ret, int num, int data)
245 {
246 int ret;
247 struct btrfs_block_group_cache *cache = *cache_ret;
248 u64 last = *start_ret;
249 u64 start = 0;
250 u64 end = 0;
251 u64 search_start = *start_ret;
252 int wrapped = 0;
253
254 if (!cache)
255 goto out;
256 again:
257 ret = cache_block_group(root, cache);
258 if (ret)
259 goto out;
260
261 last = max(search_start, cache->key.objectid);
262 if (cache->ro || !block_group_bits(cache, data))
263 goto new_group;
264
265 while(1) {
266 ret = find_first_extent_bit(&root->fs_info->free_space_cache,
267 last, &start, &end, EXTENT_DIRTY);
268 if (ret) {
269 goto new_group;
270 }
271
272 start = max(last, start);
273 last = end + 1;
274 if (last - start < num) {
275 continue;
276 }
277 if (start + num > cache->key.objectid + cache->key.offset) {
278 goto new_group;
279 }
280 *start_ret = start;
281 return 0;
282 }
283 out:
284 *start_ret = last;
285 cache = btrfs_lookup_block_group(root->fs_info, search_start);
286 if (!cache) {
287 printk("Unable to find block group for %llu\n",
288 (unsigned long long)search_start);
289 WARN_ON(1);
290 }
291 return -ENOSPC;
292
293 new_group:
294 last = cache->key.objectid + cache->key.offset;
295 wrapped:
296 cache = btrfs_lookup_first_block_group(root->fs_info, last);
297 if (!cache) {
298 if (!wrapped) {
299 wrapped = 1;
300 last = search_start;
301 goto wrapped;
302 }
303 goto out;
304 }
305 *cache_ret = cache;
306 goto again;
307 }
308
309 static int block_group_state_bits(u64 flags)
310 {
311 int bits = 0;
312 if (flags & BTRFS_BLOCK_GROUP_DATA)
313 bits |= BLOCK_GROUP_DATA;
314 if (flags & BTRFS_BLOCK_GROUP_METADATA)
315 bits |= BLOCK_GROUP_METADATA;
316 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
317 bits |= BLOCK_GROUP_SYSTEM;
318 return bits;
319 }
320
321 static struct btrfs_block_group_cache *
322 btrfs_find_block_group(struct btrfs_root *root, struct btrfs_block_group_cache
323 *hint, u64 search_start, int data, int owner)
324 {
325 struct btrfs_block_group_cache *cache;
326 struct extent_io_tree *block_group_cache;
327 struct btrfs_block_group_cache *found_group = NULL;
328 struct btrfs_fs_info *info = root->fs_info;
329 u64 used;
330 u64 last = 0;
331 u64 hint_last;
332 u64 start;
333 u64 end;
334 u64 free_check;
335 u64 ptr;
336 int bit;
337 int ret;
338 int full_search = 0;
339 int factor = 10;
340
341 block_group_cache = &info->block_group_cache;
342
343 if (!owner)
344 factor = 10;
345
346 bit = block_group_state_bits(data);
347
348 if (search_start) {
349 struct btrfs_block_group_cache *shint;
350 shint = btrfs_lookup_block_group(info, search_start);
351 if (shint && !shint->ro && block_group_bits(shint, data)) {
352 used = btrfs_block_group_used(&shint->item);
353 if (used + shint->pinned <
354 div_factor(shint->key.offset, factor)) {
355 return shint;
356 }
357 }
358 }
359 if (hint && !hint->ro && block_group_bits(hint, data)) {
360 used = btrfs_block_group_used(&hint->item);
361 if (used + hint->pinned <
362 div_factor(hint->key.offset, factor)) {
363 return hint;
364 }
365 last = hint->key.objectid + hint->key.offset;
366 hint_last = last;
367 } else {
368 if (hint)
369 hint_last = max(hint->key.objectid, search_start);
370 else
371 hint_last = search_start;
372
373 last = hint_last;
374 }
375 again:
376 while(1) {
377 ret = find_first_extent_bit(block_group_cache, last,
378 &start, &end, bit);
379 if (ret)
380 break;
381
382 ret = get_state_private(block_group_cache, start, &ptr);
383 if (ret)
384 break;
385
386 cache = (struct btrfs_block_group_cache *)(unsigned long)ptr;
387 last = cache->key.objectid + cache->key.offset;
388 used = btrfs_block_group_used(&cache->item);
389
390 if (!cache->ro && block_group_bits(cache, data)) {
391 if (full_search)
392 free_check = cache->key.offset;
393 else
394 free_check = div_factor(cache->key.offset,
395 factor);
396
397 if (used + cache->pinned < free_check) {
398 found_group = cache;
399 goto found;
400 }
401 }
402 cond_resched();
403 }
404 if (!full_search) {
405 last = search_start;
406 full_search = 1;
407 goto again;
408 }
409 found:
410 return found_group;
411 }
412
413 /*
414 * Back reference rules. Back refs have three main goals:
415 *
416 * 1) differentiate between all holders of references to an extent so that
417 * when a reference is dropped we can make sure it was a valid reference
418 * before freeing the extent.
419 *
420 * 2) Provide enough information to quickly find the holders of an extent
421 * if we notice a given block is corrupted or bad.
422 *
423 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
424 * maintenance. This is actually the same as #2, but with a slightly
425 * different use case.
426 *
427 * There are two kinds of back refs. The implicit back refs is optimized
428 * for pointers in non-shared tree blocks. For a given pointer in a block,
429 * back refs of this kind provide information about the block's owner tree
430 * and the pointer's key. These information allow us to find the block by
431 * b-tree searching. The full back refs is for pointers in tree blocks not
432 * referenced by their owner trees. The location of tree block is recorded
433 * in the back refs. Actually the full back refs is generic, and can be
434 * used in all cases the implicit back refs is used. The major shortcoming
435 * of the full back refs is its overhead. Every time a tree block gets
436 * COWed, we have to update back refs entry for all pointers in it.
437 *
438 * For a newly allocated tree block, we use implicit back refs for
439 * pointers in it. This means most tree related operations only involve
440 * implicit back refs. For a tree block created in old transaction, the
441 * only way to drop a reference to it is COW it. So we can detect the
442 * event that tree block loses its owner tree's reference and do the
443 * back refs conversion.
444 *
445 * When a tree block is COW'd through a tree, there are four cases:
446 *
447 * The reference count of the block is one and the tree is the block's
448 * owner tree. Nothing to do in this case.
449 *
450 * The reference count of the block is one and the tree is not the
451 * block's owner tree. In this case, full back refs is used for pointers
452 * in the block. Remove these full back refs, add implicit back refs for
453 * every pointers in the new block.
454 *
455 * The reference count of the block is greater than one and the tree is
456 * the block's owner tree. In this case, implicit back refs is used for
457 * pointers in the block. Add full back refs for every pointers in the
458 * block, increase lower level extents' reference counts. The original
459 * implicit back refs are entailed to the new block.
460 *
461 * The reference count of the block is greater than one and the tree is
462 * not the block's owner tree. Add implicit back refs for every pointer in
463 * the new block, increase lower level extents' reference count.
464 *
465 * Back Reference Key composing:
466 *
467 * The key objectid corresponds to the first byte in the extent,
468 * The key type is used to differentiate between types of back refs.
469 * There are different meanings of the key offset for different types
470 * of back refs.
471 *
472 * File extents can be referenced by:
473 *
474 * - multiple snapshots, subvolumes, or different generations in one subvol
475 * - different files inside a single subvolume
476 * - different offsets inside a file (bookend extents in file.c)
477 *
478 * The extent ref structure for the implicit back refs has fields for:
479 *
480 * - Objectid of the subvolume root
481 * - objectid of the file holding the reference
482 * - original offset in the file
483 * - how many bookend extents
484 *
485 * The key offset for the implicit back refs is hash of the first
486 * three fields.
487 *
488 * The extent ref structure for the full back refs has field for:
489 *
490 * - number of pointers in the tree leaf
491 *
492 * The key offset for the implicit back refs is the first byte of
493 * the tree leaf
494 *
495 * When a file extent is allocated, The implicit back refs is used.
496 * the fields are filled in:
497 *
498 * (root_key.objectid, inode objectid, offset in file, 1)
499 *
500 * When a file extent is removed file truncation, we find the
501 * corresponding implicit back refs and check the following fields:
502 *
503 * (btrfs_header_owner(leaf), inode objectid, offset in file)
504 *
505 * Btree extents can be referenced by:
506 *
507 * - Different subvolumes
508 *
509 * Both the implicit back refs and the full back refs for tree blocks
510 * only consist of key. The key offset for the implicit back refs is
511 * objectid of block's owner tree. The key offset for the full back refs
512 * is the first byte of parent block.
513 *
514 * When implicit back refs is used, information about the lowest key and
515 * level of the tree block are required. These information are stored in
516 * tree block info structure.
517 */
518
519 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
520 static int convert_extent_item_v0(struct btrfs_trans_handle *trans,
521 struct btrfs_root *root,
522 struct btrfs_path *path,
523 u64 owner, u32 extra_size)
524 {
525 struct btrfs_extent_item *item;
526 struct btrfs_extent_item_v0 *ei0;
527 struct btrfs_extent_ref_v0 *ref0;
528 struct btrfs_tree_block_info *bi;
529 struct extent_buffer *leaf;
530 struct btrfs_key key;
531 struct btrfs_key found_key;
532 u32 new_size = sizeof(*item);
533 u64 refs;
534 int ret;
535
536 leaf = path->nodes[0];
537 BUG_ON(btrfs_item_size_nr(leaf, path->slots[0]) != sizeof(*ei0));
538
539 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
540 ei0 = btrfs_item_ptr(leaf, path->slots[0],
541 struct btrfs_extent_item_v0);
542 refs = btrfs_extent_refs_v0(leaf, ei0);
543
544 if (owner == (u64)-1) {
545 while (1) {
546 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
547 ret = btrfs_next_leaf(root, path);
548 if (ret < 0)
549 return ret;
550 BUG_ON(ret > 0);
551 leaf = path->nodes[0];
552 }
553 btrfs_item_key_to_cpu(leaf, &found_key,
554 path->slots[0]);
555 BUG_ON(key.objectid != found_key.objectid);
556 if (found_key.type != BTRFS_EXTENT_REF_V0_KEY) {
557 path->slots[0]++;
558 continue;
559 }
560 ref0 = btrfs_item_ptr(leaf, path->slots[0],
561 struct btrfs_extent_ref_v0);
562 owner = btrfs_ref_objectid_v0(leaf, ref0);
563 break;
564 }
565 }
566 btrfs_release_path(path);
567
568 if (owner < BTRFS_FIRST_FREE_OBJECTID)
569 new_size += sizeof(*bi);
570
571 new_size -= sizeof(*ei0);
572 ret = btrfs_search_slot(trans, root, &key, path, new_size, 1);
573 if (ret < 0)
574 return ret;
575 BUG_ON(ret);
576
577 ret = btrfs_extend_item(trans, root, path, new_size);
578 BUG_ON(ret);
579
580 leaf = path->nodes[0];
581 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
582 btrfs_set_extent_refs(leaf, item, refs);
583 /* FIXME: get real generation */
584 btrfs_set_extent_generation(leaf, item, 0);
585 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
586 btrfs_set_extent_flags(leaf, item,
587 BTRFS_EXTENT_FLAG_TREE_BLOCK |
588 BTRFS_BLOCK_FLAG_FULL_BACKREF);
589 bi = (struct btrfs_tree_block_info *)(item + 1);
590 /* FIXME: get first key of the block */
591 memset_extent_buffer(leaf, 0, (unsigned long)bi, sizeof(*bi));
592 btrfs_set_tree_block_level(leaf, bi, (int)owner);
593 } else {
594 btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_DATA);
595 }
596 btrfs_mark_buffer_dirty(leaf);
597 return 0;
598 }
599 #endif
600
601 static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
602 {
603 u32 high_crc = ~(u32)0;
604 u32 low_crc = ~(u32)0;
605 __le64 lenum;
606
607 lenum = cpu_to_le64(root_objectid);
608 high_crc = btrfs_crc32c(high_crc, &lenum, sizeof(lenum));
609 lenum = cpu_to_le64(owner);
610 low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
611 lenum = cpu_to_le64(offset);
612 low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
613
614 return ((u64)high_crc << 31) ^ (u64)low_crc;
615 }
616
617 static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
618 struct btrfs_extent_data_ref *ref)
619 {
620 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
621 btrfs_extent_data_ref_objectid(leaf, ref),
622 btrfs_extent_data_ref_offset(leaf, ref));
623 }
624
625 static int match_extent_data_ref(struct extent_buffer *leaf,
626 struct btrfs_extent_data_ref *ref,
627 u64 root_objectid, u64 owner, u64 offset)
628 {
629 if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
630 btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
631 btrfs_extent_data_ref_offset(leaf, ref) != offset)
632 return 0;
633 return 1;
634 }
635
636 static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
637 struct btrfs_root *root,
638 struct btrfs_path *path,
639 u64 bytenr, u64 parent,
640 u64 root_objectid,
641 u64 owner, u64 offset)
642 {
643 struct btrfs_key key;
644 struct btrfs_extent_data_ref *ref;
645 struct extent_buffer *leaf;
646 u32 nritems;
647 int ret;
648 int recow;
649 int err = -ENOENT;
650
651 key.objectid = bytenr;
652 if (parent) {
653 key.type = BTRFS_SHARED_DATA_REF_KEY;
654 key.offset = parent;
655 } else {
656 key.type = BTRFS_EXTENT_DATA_REF_KEY;
657 key.offset = hash_extent_data_ref(root_objectid,
658 owner, offset);
659 }
660 again:
661 recow = 0;
662 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
663 if (ret < 0) {
664 err = ret;
665 goto fail;
666 }
667
668 if (parent) {
669 if (!ret)
670 return 0;
671 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
672 key.type = BTRFS_EXTENT_REF_V0_KEY;
673 btrfs_release_path(path);
674 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
675 if (ret < 0) {
676 err = ret;
677 goto fail;
678 }
679 if (!ret)
680 return 0;
681 #endif
682 goto fail;
683 }
684
685 leaf = path->nodes[0];
686 nritems = btrfs_header_nritems(leaf);
687 while (1) {
688 if (path->slots[0] >= nritems) {
689 ret = btrfs_next_leaf(root, path);
690 if (ret < 0)
691 err = ret;
692 if (ret)
693 goto fail;
694
695 leaf = path->nodes[0];
696 nritems = btrfs_header_nritems(leaf);
697 recow = 1;
698 }
699
700 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
701 if (key.objectid != bytenr ||
702 key.type != BTRFS_EXTENT_DATA_REF_KEY)
703 goto fail;
704
705 ref = btrfs_item_ptr(leaf, path->slots[0],
706 struct btrfs_extent_data_ref);
707
708 if (match_extent_data_ref(leaf, ref, root_objectid,
709 owner, offset)) {
710 if (recow) {
711 btrfs_release_path(path);
712 goto again;
713 }
714 err = 0;
715 break;
716 }
717 path->slots[0]++;
718 }
719 fail:
720 return err;
721 }
722
723 static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
724 struct btrfs_root *root,
725 struct btrfs_path *path,
726 u64 bytenr, u64 parent,
727 u64 root_objectid, u64 owner,
728 u64 offset, int refs_to_add)
729 {
730 struct btrfs_key key;
731 struct extent_buffer *leaf;
732 u32 size;
733 u32 num_refs;
734 int ret;
735
736 key.objectid = bytenr;
737 if (parent) {
738 key.type = BTRFS_SHARED_DATA_REF_KEY;
739 key.offset = parent;
740 size = sizeof(struct btrfs_shared_data_ref);
741 } else {
742 key.type = BTRFS_EXTENT_DATA_REF_KEY;
743 key.offset = hash_extent_data_ref(root_objectid,
744 owner, offset);
745 size = sizeof(struct btrfs_extent_data_ref);
746 }
747
748 ret = btrfs_insert_empty_item(trans, root, path, &key, size);
749 if (ret && ret != -EEXIST)
750 goto fail;
751
752 leaf = path->nodes[0];
753 if (parent) {
754 struct btrfs_shared_data_ref *ref;
755 ref = btrfs_item_ptr(leaf, path->slots[0],
756 struct btrfs_shared_data_ref);
757 if (ret == 0) {
758 btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
759 } else {
760 num_refs = btrfs_shared_data_ref_count(leaf, ref);
761 num_refs += refs_to_add;
762 btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
763 }
764 } else {
765 struct btrfs_extent_data_ref *ref;
766 while (ret == -EEXIST) {
767 ref = btrfs_item_ptr(leaf, path->slots[0],
768 struct btrfs_extent_data_ref);
769 if (match_extent_data_ref(leaf, ref, root_objectid,
770 owner, offset))
771 break;
772 btrfs_release_path(path);
773
774 key.offset++;
775 ret = btrfs_insert_empty_item(trans, root, path, &key,
776 size);
777 if (ret && ret != -EEXIST)
778 goto fail;
779
780 leaf = path->nodes[0];
781 }
782 ref = btrfs_item_ptr(leaf, path->slots[0],
783 struct btrfs_extent_data_ref);
784 if (ret == 0) {
785 btrfs_set_extent_data_ref_root(leaf, ref,
786 root_objectid);
787 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
788 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
789 btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
790 } else {
791 num_refs = btrfs_extent_data_ref_count(leaf, ref);
792 num_refs += refs_to_add;
793 btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
794 }
795 }
796 btrfs_mark_buffer_dirty(leaf);
797 ret = 0;
798 fail:
799 btrfs_release_path(path);
800 return ret;
801 }
802
803 static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
804 struct btrfs_root *root,
805 struct btrfs_path *path,
806 int refs_to_drop)
807 {
808 struct btrfs_key key;
809 struct btrfs_extent_data_ref *ref1 = NULL;
810 struct btrfs_shared_data_ref *ref2 = NULL;
811 struct extent_buffer *leaf;
812 u32 num_refs = 0;
813 int ret = 0;
814
815 leaf = path->nodes[0];
816 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
817
818 if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
819 ref1 = btrfs_item_ptr(leaf, path->slots[0],
820 struct btrfs_extent_data_ref);
821 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
822 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
823 ref2 = btrfs_item_ptr(leaf, path->slots[0],
824 struct btrfs_shared_data_ref);
825 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
826 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
827 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
828 struct btrfs_extent_ref_v0 *ref0;
829 ref0 = btrfs_item_ptr(leaf, path->slots[0],
830 struct btrfs_extent_ref_v0);
831 num_refs = btrfs_ref_count_v0(leaf, ref0);
832 #endif
833 } else {
834 BUG();
835 }
836
837 BUG_ON(num_refs < refs_to_drop);
838 num_refs -= refs_to_drop;
839
840 if (num_refs == 0) {
841 ret = btrfs_del_item(trans, root, path);
842 } else {
843 if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
844 btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
845 else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
846 btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
847 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
848 else {
849 struct btrfs_extent_ref_v0 *ref0;
850 ref0 = btrfs_item_ptr(leaf, path->slots[0],
851 struct btrfs_extent_ref_v0);
852 btrfs_set_ref_count_v0(leaf, ref0, num_refs);
853 }
854 #endif
855 btrfs_mark_buffer_dirty(leaf);
856 }
857 return ret;
858 }
859
860 static noinline u32 extent_data_ref_count(struct btrfs_root *root,
861 struct btrfs_path *path,
862 struct btrfs_extent_inline_ref *iref)
863 {
864 struct btrfs_key key;
865 struct extent_buffer *leaf;
866 struct btrfs_extent_data_ref *ref1;
867 struct btrfs_shared_data_ref *ref2;
868 u32 num_refs = 0;
869
870 leaf = path->nodes[0];
871 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
872 if (iref) {
873 if (btrfs_extent_inline_ref_type(leaf, iref) ==
874 BTRFS_EXTENT_DATA_REF_KEY) {
875 ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
876 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
877 } else {
878 ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
879 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
880 }
881 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
882 ref1 = btrfs_item_ptr(leaf, path->slots[0],
883 struct btrfs_extent_data_ref);
884 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
885 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
886 ref2 = btrfs_item_ptr(leaf, path->slots[0],
887 struct btrfs_shared_data_ref);
888 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
889 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
890 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
891 struct btrfs_extent_ref_v0 *ref0;
892 ref0 = btrfs_item_ptr(leaf, path->slots[0],
893 struct btrfs_extent_ref_v0);
894 num_refs = btrfs_ref_count_v0(leaf, ref0);
895 #endif
896 } else {
897 BUG();
898 }
899 return num_refs;
900 }
901
902 static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
903 struct btrfs_root *root,
904 struct btrfs_path *path,
905 u64 bytenr, u64 parent,
906 u64 root_objectid)
907 {
908 struct btrfs_key key;
909 int ret;
910
911 key.objectid = bytenr;
912 if (parent) {
913 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
914 key.offset = parent;
915 } else {
916 key.type = BTRFS_TREE_BLOCK_REF_KEY;
917 key.offset = root_objectid;
918 }
919
920 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
921 if (ret > 0)
922 ret = -ENOENT;
923 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
924 if (ret == -ENOENT && parent) {
925 btrfs_release_path(path);
926 key.type = BTRFS_EXTENT_REF_V0_KEY;
927 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
928 if (ret > 0)
929 ret = -ENOENT;
930 }
931 #endif
932 return ret;
933 }
934
935 static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
936 struct btrfs_root *root,
937 struct btrfs_path *path,
938 u64 bytenr, u64 parent,
939 u64 root_objectid)
940 {
941 struct btrfs_key key;
942 int ret;
943
944 key.objectid = bytenr;
945 if (parent) {
946 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
947 key.offset = parent;
948 } else {
949 key.type = BTRFS_TREE_BLOCK_REF_KEY;
950 key.offset = root_objectid;
951 }
952
953 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
954
955 btrfs_release_path(path);
956 return ret;
957 }
958
959 static inline int extent_ref_type(u64 parent, u64 owner)
960 {
961 int type;
962 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
963 if (parent > 0)
964 type = BTRFS_SHARED_BLOCK_REF_KEY;
965 else
966 type = BTRFS_TREE_BLOCK_REF_KEY;
967 } else {
968 if (parent > 0)
969 type = BTRFS_SHARED_DATA_REF_KEY;
970 else
971 type = BTRFS_EXTENT_DATA_REF_KEY;
972 }
973 return type;
974 }
975
976 static int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
977 struct btrfs_root *root,
978 struct btrfs_path *path,
979 struct btrfs_extent_inline_ref **ref_ret,
980 u64 bytenr, u64 num_bytes,
981 u64 parent, u64 root_objectid,
982 u64 owner, u64 offset, int insert)
983 {
984 struct btrfs_key key;
985 struct extent_buffer *leaf;
986 struct btrfs_extent_item *ei;
987 struct btrfs_extent_inline_ref *iref;
988 u64 flags;
989 u32 item_size;
990 unsigned long ptr;
991 unsigned long end;
992 int extra_size;
993 int type;
994 int want;
995 int ret;
996 int err = 0;
997 int skinny_metadata =
998 btrfs_fs_incompat(root->fs_info,
999 BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA);
1000
1001 key.objectid = bytenr;
1002 key.type = BTRFS_EXTENT_ITEM_KEY;
1003 key.offset = num_bytes;
1004
1005 want = extent_ref_type(parent, owner);
1006 if (insert)
1007 extra_size = btrfs_extent_inline_ref_size(want);
1008 else
1009 extra_size = -1;
1010
1011 if (owner < BTRFS_FIRST_FREE_OBJECTID && skinny_metadata) {
1012 skinny_metadata = 1;
1013 key.type = BTRFS_METADATA_ITEM_KEY;
1014 key.offset = owner;
1015 } else if (skinny_metadata) {
1016 skinny_metadata = 0;
1017 }
1018
1019 again:
1020 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
1021 if (ret < 0) {
1022 err = ret;
1023 goto out;
1024 }
1025
1026 /*
1027 * We may be a newly converted file system which still has the old fat
1028 * extent entries for metadata, so try and see if we have one of those.
1029 */
1030 if (ret > 0 && skinny_metadata) {
1031 skinny_metadata = 0;
1032 if (path->slots[0]) {
1033 path->slots[0]--;
1034 btrfs_item_key_to_cpu(path->nodes[0], &key,
1035 path->slots[0]);
1036 if (key.objectid == bytenr &&
1037 key.type == BTRFS_EXTENT_ITEM_KEY &&
1038 key.offset == num_bytes)
1039 ret = 0;
1040 }
1041 if (ret) {
1042 key.type = BTRFS_EXTENT_ITEM_KEY;
1043 key.offset = num_bytes;
1044 btrfs_release_path(path);
1045 goto again;
1046 }
1047 }
1048
1049 if (ret) {
1050 printf("Failed to find [%llu, %u, %llu]\n", key.objectid, key.type, key.offset);
1051 return -ENOENT;
1052 }
1053
1054 BUG_ON(ret);
1055
1056 leaf = path->nodes[0];
1057 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1058 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1059 if (item_size < sizeof(*ei)) {
1060 if (!insert) {
1061 err = -ENOENT;
1062 goto out;
1063 }
1064 ret = convert_extent_item_v0(trans, root, path, owner,
1065 extra_size);
1066 if (ret < 0) {
1067 err = ret;
1068 goto out;
1069 }
1070 leaf = path->nodes[0];
1071 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1072 }
1073 #endif
1074 if (item_size < sizeof(*ei)) {
1075 printf("Size is %u, needs to be %u, slot %d\n",
1076 (unsigned)item_size,
1077 (unsigned)sizeof(*ei), path->slots[0]);
1078 btrfs_print_leaf(root, leaf);
1079 return -EINVAL;
1080 }
1081 BUG_ON(item_size < sizeof(*ei));
1082
1083 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1084 flags = btrfs_extent_flags(leaf, ei);
1085
1086 ptr = (unsigned long)(ei + 1);
1087 end = (unsigned long)ei + item_size;
1088
1089 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK && !skinny_metadata) {
1090 ptr += sizeof(struct btrfs_tree_block_info);
1091 BUG_ON(ptr > end);
1092 } else if (!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) {
1093 if (!(flags & BTRFS_EXTENT_FLAG_DATA)) {
1094 return -EIO;
1095 }
1096 }
1097
1098 err = -ENOENT;
1099 while (1) {
1100 if (ptr >= end) {
1101 WARN_ON(ptr > end);
1102 break;
1103 }
1104 iref = (struct btrfs_extent_inline_ref *)ptr;
1105 type = btrfs_extent_inline_ref_type(leaf, iref);
1106 if (want < type)
1107 break;
1108 if (want > type) {
1109 ptr += btrfs_extent_inline_ref_size(type);
1110 continue;
1111 }
1112
1113 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1114 struct btrfs_extent_data_ref *dref;
1115 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1116 if (match_extent_data_ref(leaf, dref, root_objectid,
1117 owner, offset)) {
1118 err = 0;
1119 break;
1120 }
1121 if (hash_extent_data_ref_item(leaf, dref) <
1122 hash_extent_data_ref(root_objectid, owner, offset))
1123 break;
1124 } else {
1125 u64 ref_offset;
1126 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1127 if (parent > 0) {
1128 if (parent == ref_offset) {
1129 err = 0;
1130 break;
1131 }
1132 if (ref_offset < parent)
1133 break;
1134 } else {
1135 if (root_objectid == ref_offset) {
1136 err = 0;
1137 break;
1138 }
1139 if (ref_offset < root_objectid)
1140 break;
1141 }
1142 }
1143 ptr += btrfs_extent_inline_ref_size(type);
1144 }
1145 if (err == -ENOENT && insert) {
1146 if (item_size + extra_size >=
1147 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
1148 err = -EAGAIN;
1149 goto out;
1150 }
1151 /*
1152 * To add new inline back ref, we have to make sure
1153 * there is no corresponding back ref item.
1154 * For simplicity, we just do not add new inline back
1155 * ref if there is any back ref item.
1156 */
1157 if (find_next_key(path, &key) == 0 && key.objectid == bytenr &&
1158 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
1159 err = -EAGAIN;
1160 goto out;
1161 }
1162 }
1163 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
1164 out:
1165 return err;
1166 }
1167
1168 static int setup_inline_extent_backref(struct btrfs_trans_handle *trans,
1169 struct btrfs_root *root,
1170 struct btrfs_path *path,
1171 struct btrfs_extent_inline_ref *iref,
1172 u64 parent, u64 root_objectid,
1173 u64 owner, u64 offset, int refs_to_add)
1174 {
1175 struct extent_buffer *leaf;
1176 struct btrfs_extent_item *ei;
1177 unsigned long ptr;
1178 unsigned long end;
1179 unsigned long item_offset;
1180 u64 refs;
1181 int size;
1182 int type;
1183 int ret;
1184
1185 leaf = path->nodes[0];
1186 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1187 item_offset = (unsigned long)iref - (unsigned long)ei;
1188
1189 type = extent_ref_type(parent, owner);
1190 size = btrfs_extent_inline_ref_size(type);
1191
1192 ret = btrfs_extend_item(trans, root, path, size);
1193 BUG_ON(ret);
1194
1195 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1196 refs = btrfs_extent_refs(leaf, ei);
1197 refs += refs_to_add;
1198 btrfs_set_extent_refs(leaf, ei, refs);
1199
1200 ptr = (unsigned long)ei + item_offset;
1201 end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
1202 if (ptr < end - size)
1203 memmove_extent_buffer(leaf, ptr + size, ptr,
1204 end - size - ptr);
1205
1206 iref = (struct btrfs_extent_inline_ref *)ptr;
1207 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1208 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1209 struct btrfs_extent_data_ref *dref;
1210 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1211 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1212 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1213 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1214 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1215 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1216 struct btrfs_shared_data_ref *sref;
1217 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1218 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1219 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1220 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1221 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1222 } else {
1223 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1224 }
1225 btrfs_mark_buffer_dirty(leaf);
1226 return 0;
1227 }
1228
1229 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1230 struct btrfs_root *root,
1231 struct btrfs_path *path,
1232 struct btrfs_extent_inline_ref **ref_ret,
1233 u64 bytenr, u64 num_bytes, u64 parent,
1234 u64 root_objectid, u64 owner, u64 offset)
1235 {
1236 int ret;
1237
1238 ret = lookup_inline_extent_backref(trans, root, path, ref_ret,
1239 bytenr, num_bytes, parent,
1240 root_objectid, owner, offset, 0);
1241 if (ret != -ENOENT)
1242 return ret;
1243
1244 btrfs_release_path(path);
1245 *ref_ret = NULL;
1246
1247 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1248 ret = lookup_tree_block_ref(trans, root, path, bytenr, parent,
1249 root_objectid);
1250 } else {
1251 ret = lookup_extent_data_ref(trans, root, path, bytenr, parent,
1252 root_objectid, owner, offset);
1253 }
1254 return ret;
1255 }
1256
1257 static int update_inline_extent_backref(struct btrfs_trans_handle *trans,
1258 struct btrfs_root *root,
1259 struct btrfs_path *path,
1260 struct btrfs_extent_inline_ref *iref,
1261 int refs_to_mod)
1262 {
1263 struct extent_buffer *leaf;
1264 struct btrfs_extent_item *ei;
1265 struct btrfs_extent_data_ref *dref = NULL;
1266 struct btrfs_shared_data_ref *sref = NULL;
1267 unsigned long ptr;
1268 unsigned long end;
1269 u32 item_size;
1270 int size;
1271 int type;
1272 int ret;
1273 u64 refs;
1274
1275 leaf = path->nodes[0];
1276 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1277 refs = btrfs_extent_refs(leaf, ei);
1278 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1279 refs += refs_to_mod;
1280 btrfs_set_extent_refs(leaf, ei, refs);
1281
1282 type = btrfs_extent_inline_ref_type(leaf, iref);
1283
1284 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1285 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1286 refs = btrfs_extent_data_ref_count(leaf, dref);
1287 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1288 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1289 refs = btrfs_shared_data_ref_count(leaf, sref);
1290 } else {
1291 refs = 1;
1292 BUG_ON(refs_to_mod != -1);
1293 }
1294
1295 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1296 refs += refs_to_mod;
1297
1298 if (refs > 0) {
1299 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1300 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1301 else
1302 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1303 } else {
1304 size = btrfs_extent_inline_ref_size(type);
1305 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1306 ptr = (unsigned long)iref;
1307 end = (unsigned long)ei + item_size;
1308 if (ptr + size < end)
1309 memmove_extent_buffer(leaf, ptr, ptr + size,
1310 end - ptr - size);
1311 item_size -= size;
1312 ret = btrfs_truncate_item(trans, root, path, item_size, 1);
1313 BUG_ON(ret);
1314 }
1315 btrfs_mark_buffer_dirty(leaf);
1316 return 0;
1317 }
1318
1319 static int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1320 struct btrfs_root *root,
1321 struct btrfs_path *path,
1322 u64 bytenr, u64 num_bytes, u64 parent,
1323 u64 root_objectid, u64 owner,
1324 u64 offset, int refs_to_add)
1325 {
1326 struct btrfs_extent_inline_ref *iref;
1327 int ret;
1328
1329 ret = lookup_inline_extent_backref(trans, root, path, &iref,
1330 bytenr, num_bytes, parent,
1331 root_objectid, owner, offset, 1);
1332 if (ret == 0) {
1333 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
1334 ret = update_inline_extent_backref(trans, root, path, iref,
1335 refs_to_add);
1336 } else if (ret == -ENOENT) {
1337 ret = setup_inline_extent_backref(trans, root, path, iref,
1338 parent, root_objectid,
1339 owner, offset, refs_to_add);
1340 }
1341 return ret;
1342 }
1343
1344 static int insert_extent_backref(struct btrfs_trans_handle *trans,
1345 struct btrfs_root *root,
1346 struct btrfs_path *path,
1347 u64 bytenr, u64 parent, u64 root_objectid,
1348 u64 owner, u64 offset, int refs_to_add)
1349 {
1350 int ret;
1351
1352 if (owner >= BTRFS_FIRST_FREE_OBJECTID) {
1353 ret = insert_extent_data_ref(trans, root, path, bytenr,
1354 parent, root_objectid,
1355 owner, offset, refs_to_add);
1356 } else {
1357 BUG_ON(refs_to_add != 1);
1358 ret = insert_tree_block_ref(trans, root, path, bytenr,
1359 parent, root_objectid);
1360 }
1361 return ret;
1362 }
1363
1364 static int remove_extent_backref(struct btrfs_trans_handle *trans,
1365 struct btrfs_root *root,
1366 struct btrfs_path *path,
1367 struct btrfs_extent_inline_ref *iref,
1368 int refs_to_drop, int is_data)
1369 {
1370 int ret;
1371
1372 BUG_ON(!is_data && refs_to_drop != 1);
1373 if (iref) {
1374 ret = update_inline_extent_backref(trans, root, path, iref,
1375 -refs_to_drop);
1376 } else if (is_data) {
1377 ret = remove_extent_data_ref(trans, root, path, refs_to_drop);
1378 } else {
1379 ret = btrfs_del_item(trans, root, path);
1380 }
1381 return ret;
1382 }
1383
1384 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1385 struct btrfs_root *root,
1386 u64 bytenr, u64 num_bytes, u64 parent,
1387 u64 root_objectid, u64 owner, u64 offset)
1388 {
1389 struct btrfs_path *path;
1390 struct extent_buffer *leaf;
1391 struct btrfs_extent_item *item;
1392 u64 refs;
1393 int ret;
1394 int err = 0;
1395
1396 path = btrfs_alloc_path();
1397 if (!path)
1398 return -ENOMEM;
1399
1400 path->reada = 1;
1401
1402 ret = insert_inline_extent_backref(trans, root->fs_info->extent_root,
1403 path, bytenr, num_bytes, parent,
1404 root_objectid, owner, offset, 1);
1405 if (ret == 0)
1406 goto out;
1407
1408 if (ret != -EAGAIN) {
1409 err = ret;
1410 goto out;
1411 }
1412
1413 leaf = path->nodes[0];
1414 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1415 refs = btrfs_extent_refs(leaf, item);
1416 btrfs_set_extent_refs(leaf, item, refs + 1);
1417
1418 btrfs_mark_buffer_dirty(leaf);
1419 btrfs_release_path(path);
1420
1421 path->reada = 1;
1422
1423 /* now insert the actual backref */
1424 ret = insert_extent_backref(trans, root->fs_info->extent_root,
1425 path, bytenr, parent, root_objectid,
1426 owner, offset, 1);
1427 if (ret)
1428 err = ret;
1429 out:
1430 btrfs_free_path(path);
1431 finish_current_insert(trans, root->fs_info->extent_root);
1432 del_pending_extents(trans, root->fs_info->extent_root);
1433 BUG_ON(err);
1434 return err;
1435 }
1436
1437 int btrfs_extent_post_op(struct btrfs_trans_handle *trans,
1438 struct btrfs_root *root)
1439 {
1440 finish_current_insert(trans, root->fs_info->extent_root);
1441 del_pending_extents(trans, root->fs_info->extent_root);
1442 return 0;
1443 }
1444
1445 int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
1446 struct btrfs_root *root, u64 bytenr,
1447 u64 offset, int metadata, u64 *refs, u64 *flags)
1448 {
1449 struct btrfs_path *path;
1450 int ret;
1451 struct btrfs_key key;
1452 struct extent_buffer *l;
1453 struct btrfs_extent_item *item;
1454 u32 item_size;
1455 u64 num_refs;
1456 u64 extent_flags;
1457
1458 if (metadata &&
1459 !btrfs_fs_incompat(root->fs_info,
1460 BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA)) {
1461 offset = root->leafsize;
1462 metadata = 0;
1463 }
1464
1465 path = btrfs_alloc_path();
1466 if (!path)
1467 return -ENOMEM;
1468 path->reada = 1;
1469
1470 key.objectid = bytenr;
1471 key.offset = offset;
1472 if (metadata)
1473 key.type = BTRFS_METADATA_ITEM_KEY;
1474 else
1475 key.type = BTRFS_EXTENT_ITEM_KEY;
1476
1477 again:
1478 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path,
1479 0, 0);
1480 if (ret < 0)
1481 goto out;
1482
1483 /*
1484 * Deal with the fact that we may have mixed SKINNY and normal refs. If
1485 * we didn't find what we wanted check and see if we have a normal ref
1486 * right next to us, or re-search if we are on the edge of the leaf just
1487 * to make sure.
1488 */
1489 if (ret > 0 && metadata) {
1490 if (path->slots[0]) {
1491 path->slots[0]--;
1492 btrfs_item_key_to_cpu(path->nodes[0], &key,
1493 path->slots[0]);
1494 if (key.objectid == bytenr &&
1495 key.type == BTRFS_EXTENT_ITEM_KEY &&
1496 key.offset == root->leafsize)
1497 ret = 0;
1498 }
1499
1500 if (ret) {
1501 btrfs_release_path(path);
1502 key.type = BTRFS_EXTENT_ITEM_KEY;
1503 key.offset = root->leafsize;
1504 metadata = 0;
1505 goto again;
1506 }
1507 }
1508
1509 if (ret != 0) {
1510 ret = -EIO;
1511 goto out;
1512 }
1513
1514 l = path->nodes[0];
1515 item_size = btrfs_item_size_nr(l, path->slots[0]);
1516 if (item_size >= sizeof(*item)) {
1517 item = btrfs_item_ptr(l, path->slots[0],
1518 struct btrfs_extent_item);
1519 num_refs = btrfs_extent_refs(l, item);
1520 extent_flags = btrfs_extent_flags(l, item);
1521 } else {
1522 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1523 struct btrfs_extent_item_v0 *ei0;
1524 BUG_ON(item_size != sizeof(*ei0));
1525 ei0 = btrfs_item_ptr(l, path->slots[0],
1526 struct btrfs_extent_item_v0);
1527 num_refs = btrfs_extent_refs_v0(l, ei0);
1528 /* FIXME: this isn't correct for data */
1529 extent_flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
1530 #else
1531 BUG();
1532 #endif
1533 }
1534 item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
1535 if (refs)
1536 *refs = num_refs;
1537 if (flags)
1538 *flags = extent_flags;
1539 out:
1540 btrfs_free_path(path);
1541 return ret;
1542 }
1543
1544 int btrfs_set_block_flags(struct btrfs_trans_handle *trans,
1545 struct btrfs_root *root,
1546 u64 bytenr, int level, u64 flags)
1547 {
1548 struct btrfs_path *path;
1549 int ret;
1550 struct btrfs_key key;
1551 struct extent_buffer *l;
1552 struct btrfs_extent_item *item;
1553 u32 item_size;
1554 int skinny_metadata =
1555 btrfs_fs_incompat(root->fs_info,
1556 BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA);
1557
1558 path = btrfs_alloc_path();
1559 if (!path)
1560 return -ENOMEM;
1561 path->reada = 1;
1562
1563 key.objectid = bytenr;
1564 if (skinny_metadata) {
1565 key.offset = level;
1566 key.type = BTRFS_METADATA_ITEM_KEY;
1567 } else {
1568 key.offset = root->leafsize;
1569 key.type = BTRFS_EXTENT_ITEM_KEY;
1570 }
1571
1572 again:
1573 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path,
1574 0, 0);
1575 if (ret < 0)
1576 goto out;
1577
1578 if (ret > 0 && skinny_metadata) {
1579 skinny_metadata = 0;
1580 if (path->slots[0]) {
1581 path->slots[0]--;
1582 btrfs_item_key_to_cpu(path->nodes[0], &key,
1583 path->slots[0]);
1584 if (key.objectid == bytenr &&
1585 key.offset == root->leafsize &&
1586 key.type == BTRFS_EXTENT_ITEM_KEY)
1587 ret = 0;
1588 }
1589 if (ret) {
1590 btrfs_release_path(path);
1591 key.offset = root->leafsize;
1592 key.type = BTRFS_EXTENT_ITEM_KEY;
1593 goto again;
1594 }
1595 }
1596
1597 if (ret != 0) {
1598 btrfs_print_leaf(root, path->nodes[0]);
1599 printk("failed to find block number %Lu\n",
1600 (unsigned long long)bytenr);
1601 BUG();
1602 }
1603 l = path->nodes[0];
1604 item_size = btrfs_item_size_nr(l, path->slots[0]);
1605 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1606 if (item_size < sizeof(*item)) {
1607 ret = convert_extent_item_v0(trans, root->fs_info->extent_root,
1608 path, (u64)-1, 0);
1609 if (ret < 0)
1610 goto out;
1611
1612 l = path->nodes[0];
1613 item_size = btrfs_item_size_nr(l, path->slots[0]);
1614 }
1615 #endif
1616 BUG_ON(item_size < sizeof(*item));
1617 item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
1618 flags |= btrfs_extent_flags(l, item);
1619 btrfs_set_extent_flags(l, item, flags);
1620 out:
1621 btrfs_free_path(path);
1622 finish_current_insert(trans, root->fs_info->extent_root);
1623 del_pending_extents(trans, root->fs_info->extent_root);
1624 return ret;
1625 }
1626
1627 static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
1628 struct btrfs_root *root,
1629 struct extent_buffer *buf,
1630 int record_parent, int inc)
1631 {
1632 u64 bytenr;
1633 u64 num_bytes;
1634 u64 parent;
1635 u64 ref_root;
1636 u32 nritems;
1637 struct btrfs_key key;
1638 struct btrfs_file_extent_item *fi;
1639 int i;
1640 int level;
1641 int ret = 0;
1642 int (*process_func)(struct btrfs_trans_handle *trans,
1643 struct btrfs_root *root,
1644 u64, u64, u64, u64, u64, u64);
1645
1646 ref_root = btrfs_header_owner(buf);
1647 nritems = btrfs_header_nritems(buf);
1648 level = btrfs_header_level(buf);
1649
1650 if (!root->ref_cows && level == 0)
1651 return 0;
1652
1653 if (inc)
1654 process_func = btrfs_inc_extent_ref;
1655 else
1656 process_func = btrfs_free_extent;
1657
1658 if (record_parent)
1659 parent = buf->start;
1660 else
1661 parent = 0;
1662
1663 for (i = 0; i < nritems; i++) {
1664 cond_resched();
1665 if (level == 0) {
1666 btrfs_item_key_to_cpu(buf, &key, i);
1667 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
1668 continue;
1669 fi = btrfs_item_ptr(buf, i,
1670 struct btrfs_file_extent_item);
1671 if (btrfs_file_extent_type(buf, fi) ==
1672 BTRFS_FILE_EXTENT_INLINE)
1673 continue;
1674 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
1675 if (bytenr == 0)
1676 continue;
1677
1678 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
1679 key.offset -= btrfs_file_extent_offset(buf, fi);
1680 ret = process_func(trans, root, bytenr, num_bytes,
1681 parent, ref_root, key.objectid,
1682 key.offset);
1683 if (ret) {
1684 WARN_ON(1);
1685 goto fail;
1686 }
1687 } else {
1688 bytenr = btrfs_node_blockptr(buf, i);
1689 num_bytes = btrfs_level_size(root, level - 1);
1690 ret = process_func(trans, root, bytenr, num_bytes,
1691 parent, ref_root, level - 1, 0);
1692 if (ret) {
1693 WARN_ON(1);
1694 goto fail;
1695 }
1696 }
1697 }
1698 return 0;
1699 fail:
1700 WARN_ON(1);
1701 return ret;
1702 }
1703
1704 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
1705 struct extent_buffer *buf, int record_parent)
1706 {
1707 return __btrfs_mod_ref(trans, root, buf, record_parent, 1);
1708 }
1709
1710 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
1711 struct extent_buffer *buf, int record_parent)
1712 {
1713 return __btrfs_mod_ref(trans, root, buf, record_parent, 0);
1714 }
1715
1716 static int write_one_cache_group(struct btrfs_trans_handle *trans,
1717 struct btrfs_root *root,
1718 struct btrfs_path *path,
1719 struct btrfs_block_group_cache *cache)
1720 {
1721 int ret;
1722 int pending_ret;
1723 struct btrfs_root *extent_root = root->fs_info->extent_root;
1724 unsigned long bi;
1725 struct extent_buffer *leaf;
1726
1727 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
1728 if (ret < 0)
1729 goto fail;
1730 BUG_ON(ret);
1731
1732 leaf = path->nodes[0];
1733 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
1734 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
1735 btrfs_mark_buffer_dirty(leaf);
1736 btrfs_release_path(path);
1737 fail:
1738 finish_current_insert(trans, extent_root);
1739 pending_ret = del_pending_extents(trans, extent_root);
1740 if (ret)
1741 return ret;
1742 if (pending_ret)
1743 return pending_ret;
1744 return 0;
1745
1746 }
1747
1748 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
1749 struct btrfs_root *root)
1750 {
1751 struct extent_io_tree *block_group_cache;
1752 struct btrfs_block_group_cache *cache;
1753 int ret;
1754 struct btrfs_path *path;
1755 u64 last = 0;
1756 u64 start;
1757 u64 end;
1758 u64 ptr;
1759
1760 block_group_cache = &root->fs_info->block_group_cache;
1761 path = btrfs_alloc_path();
1762 if (!path)
1763 return -ENOMEM;
1764
1765 while(1) {
1766 ret = find_first_extent_bit(block_group_cache, last,
1767 &start, &end, BLOCK_GROUP_DIRTY);
1768 if (ret) {
1769 if (last == 0)
1770 break;
1771 last = 0;
1772 continue;
1773 }
1774
1775 last = end + 1;
1776 ret = get_state_private(block_group_cache, start, &ptr);
1777 BUG_ON(ret);
1778
1779 clear_extent_bits(block_group_cache, start, end,
1780 BLOCK_GROUP_DIRTY, GFP_NOFS);
1781
1782 cache = (struct btrfs_block_group_cache *)(unsigned long)ptr;
1783 ret = write_one_cache_group(trans, root, path, cache);
1784 }
1785 btrfs_free_path(path);
1786 return 0;
1787 }
1788
1789 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
1790 u64 flags)
1791 {
1792 struct list_head *head = &info->space_info;
1793 struct list_head *cur;
1794 struct btrfs_space_info *found;
1795 list_for_each(cur, head) {
1796 found = list_entry(cur, struct btrfs_space_info, list);
1797 if (found->flags & flags)
1798 return found;
1799 }
1800 return NULL;
1801
1802 }
1803
1804 static int update_space_info(struct btrfs_fs_info *info, u64 flags,
1805 u64 total_bytes, u64 bytes_used,
1806 struct btrfs_space_info **space_info)
1807 {
1808 struct btrfs_space_info *found;
1809
1810 found = __find_space_info(info, flags);
1811 if (found) {
1812 found->total_bytes += total_bytes;
1813 found->bytes_used += bytes_used;
1814 if (found->total_bytes < found->bytes_used) {
1815 fprintf(stderr, "warning, bad space info total_bytes "
1816 "%llu used %llu\n",
1817 (unsigned long long)found->total_bytes,
1818 (unsigned long long)found->bytes_used);
1819 }
1820 *space_info = found;
1821 return 0;
1822 }
1823 found = kmalloc(sizeof(*found), GFP_NOFS);
1824 if (!found)
1825 return -ENOMEM;
1826
1827 list_add(&found->list, &info->space_info);
1828 found->flags = flags;
1829 found->total_bytes = total_bytes;
1830 found->bytes_used = bytes_used;
1831 found->bytes_pinned = 0;
1832 found->full = 0;
1833 *space_info = found;
1834 return 0;
1835 }
1836
1837
1838 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
1839 {
1840 u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 |
1841 BTRFS_BLOCK_GROUP_RAID1 |
1842 BTRFS_BLOCK_GROUP_RAID10 |
1843 BTRFS_BLOCK_GROUP_RAID5 |
1844 BTRFS_BLOCK_GROUP_RAID6 |
1845 BTRFS_BLOCK_GROUP_DUP);
1846 if (extra_flags) {
1847 if (flags & BTRFS_BLOCK_GROUP_DATA)
1848 fs_info->avail_data_alloc_bits |= extra_flags;
1849 if (flags & BTRFS_BLOCK_GROUP_METADATA)
1850 fs_info->avail_metadata_alloc_bits |= extra_flags;
1851 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
1852 fs_info->avail_system_alloc_bits |= extra_flags;
1853 }
1854 }
1855
1856 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
1857 struct btrfs_root *extent_root, u64 alloc_bytes,
1858 u64 flags)
1859 {
1860 struct btrfs_space_info *space_info;
1861 u64 thresh;
1862 u64 start;
1863 u64 num_bytes;
1864 int ret;
1865
1866 space_info = __find_space_info(extent_root->fs_info, flags);
1867 if (!space_info) {
1868 ret = update_space_info(extent_root->fs_info, flags,
1869 0, 0, &space_info);
1870 BUG_ON(ret);
1871 }
1872 BUG_ON(!space_info);
1873
1874 if (space_info->full)
1875 return 0;
1876
1877 thresh = div_factor(space_info->total_bytes, 7);
1878 if ((space_info->bytes_used + space_info->bytes_pinned + alloc_bytes) <
1879 thresh)
1880 return 0;
1881
1882 ret = btrfs_alloc_chunk(trans, extent_root, &start, &num_bytes,
1883 space_info->flags);
1884 if (ret == -ENOSPC) {
1885 space_info->full = 1;
1886 return 0;
1887 }
1888
1889 BUG_ON(ret);
1890
1891 ret = btrfs_make_block_group(trans, extent_root, 0, space_info->flags,
1892 BTRFS_FIRST_CHUNK_TREE_OBJECTID, start, num_bytes);
1893 BUG_ON(ret);
1894 return 0;
1895 }
1896
1897 static int update_block_group(struct btrfs_trans_handle *trans,
1898 struct btrfs_root *root,
1899 u64 bytenr, u64 num_bytes, int alloc,
1900 int mark_free)
1901 {
1902 struct btrfs_block_group_cache *cache;
1903 struct btrfs_fs_info *info = root->fs_info;
1904 u64 total = num_bytes;
1905 u64 old_val;
1906 u64 byte_in_group;
1907 u64 start;
1908 u64 end;
1909
1910 /* block accounting for super block */
1911 old_val = btrfs_super_bytes_used(info->super_copy);
1912 if (alloc)
1913 old_val += num_bytes;
1914 else
1915 old_val -= num_bytes;
1916 btrfs_set_super_bytes_used(info->super_copy, old_val);
1917
1918 /* block accounting for root item */
1919 old_val = btrfs_root_used(&root->root_item);
1920 if (alloc)
1921 old_val += num_bytes;
1922 else
1923 old_val -= num_bytes;
1924 btrfs_set_root_used(&root->root_item, old_val);
1925
1926 while(total) {
1927 cache = btrfs_lookup_block_group(info, bytenr);
1928 if (!cache) {
1929 return -1;
1930 }
1931 byte_in_group = bytenr - cache->key.objectid;
1932 WARN_ON(byte_in_group > cache->key.offset);
1933 start = cache->key.objectid;
1934 end = start + cache->key.offset - 1;
1935 set_extent_bits(&info->block_group_cache, start, end,
1936 BLOCK_GROUP_DIRTY, GFP_NOFS);
1937
1938 old_val = btrfs_block_group_used(&cache->item);
1939 num_bytes = min(total, cache->key.offset - byte_in_group);
1940
1941 if (alloc) {
1942 old_val += num_bytes;
1943 cache->space_info->bytes_used += num_bytes;
1944 } else {
1945 old_val -= num_bytes;
1946 cache->space_info->bytes_used -= num_bytes;
1947 if (mark_free) {
1948 set_extent_dirty(&info->free_space_cache,
1949 bytenr, bytenr + num_bytes - 1,
1950 GFP_NOFS);
1951 }
1952 }
1953 btrfs_set_block_group_used(&cache->item, old_val);
1954 total -= num_bytes;
1955 bytenr += num_bytes;
1956 }
1957 return 0;
1958 }
1959
1960 static int update_pinned_extents(struct btrfs_root *root,
1961 u64 bytenr, u64 num, int pin)
1962 {
1963 u64 len;
1964 struct btrfs_block_group_cache *cache;
1965 struct btrfs_fs_info *fs_info = root->fs_info;
1966
1967 if (pin) {
1968 set_extent_dirty(&fs_info->pinned_extents,
1969 bytenr, bytenr + num - 1, GFP_NOFS);
1970 } else {
1971 clear_extent_dirty(&fs_info->pinned_extents,
1972 bytenr, bytenr + num - 1, GFP_NOFS);
1973 }
1974 while (num > 0) {
1975 cache = btrfs_lookup_block_group(fs_info, bytenr);
1976 if (!cache) {
1977 len = min((u64)root->sectorsize, num);
1978 goto next;
1979 }
1980 WARN_ON(!cache);
1981 len = min(num, cache->key.offset -
1982 (bytenr - cache->key.objectid));
1983 if (pin) {
1984 cache->pinned += len;
1985 cache->space_info->bytes_pinned += len;
1986 fs_info->total_pinned += len;
1987 } else {
1988 cache->pinned -= len;
1989 cache->space_info->bytes_pinned -= len;
1990 fs_info->total_pinned -= len;
1991 }
1992 next:
1993 bytenr += len;
1994 num -= len;
1995 }
1996 return 0;
1997 }
1998
1999 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
2000 struct btrfs_root *root,
2001 struct extent_io_tree *unpin)
2002 {
2003 u64 start;
2004 u64 end;
2005 int ret;
2006 struct extent_io_tree *free_space_cache;
2007 free_space_cache = &root->fs_info->free_space_cache;
2008
2009 while(1) {
2010 ret = find_first_extent_bit(unpin, 0, &start, &end,
2011 EXTENT_DIRTY);
2012 if (ret)
2013 break;
2014 update_pinned_extents(root, start, end + 1 - start, 0);
2015 clear_extent_dirty(unpin, start, end, GFP_NOFS);
2016 set_extent_dirty(free_space_cache, start, end, GFP_NOFS);
2017 }
2018 return 0;
2019 }
2020
2021 static int extent_root_pending_ops(struct btrfs_fs_info *info)
2022 {
2023 u64 start;
2024 u64 end;
2025 int ret;
2026
2027 ret = find_first_extent_bit(&info->extent_ins, 0, &start,
2028 &end, EXTENT_LOCKED);
2029 if (!ret) {
2030 ret = find_first_extent_bit(&info->pending_del, 0, &start, &end,
2031 EXTENT_LOCKED);
2032 }
2033 return ret == 0;
2034
2035 }
2036 static int finish_current_insert(struct btrfs_trans_handle *trans,
2037 struct btrfs_root *extent_root)
2038 {
2039 u64 start;
2040 u64 end;
2041 u64 priv;
2042 struct btrfs_fs_info *info = extent_root->fs_info;
2043 struct pending_extent_op *extent_op;
2044 struct btrfs_key key;
2045 int ret;
2046 int skinny_metadata =
2047 btrfs_fs_incompat(extent_root->fs_info,
2048 BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA);
2049
2050 while(1) {
2051 ret = find_first_extent_bit(&info->extent_ins, 0, &start,
2052 &end, EXTENT_LOCKED);
2053 if (ret)
2054 break;
2055
2056 ret = get_state_private(&info->extent_ins, start, &priv);
2057 BUG_ON(ret);
2058 extent_op = (struct pending_extent_op *)(unsigned long)priv;
2059
2060 if (extent_op->type == PENDING_EXTENT_INSERT) {
2061 key.objectid = start;
2062 if (skinny_metadata) {
2063 key.offset = extent_op->level;
2064 key.type = BTRFS_METADATA_ITEM_KEY;
2065 } else {
2066 key.offset = extent_op->num_bytes;
2067 key.type = BTRFS_EXTENT_ITEM_KEY;
2068 }
2069 ret = alloc_reserved_tree_block(trans, extent_root,
2070 extent_root->root_key.objectid,
2071 trans->transid,
2072 extent_op->flags,
2073 &extent_op->key,
2074 extent_op->level, &key);
2075 BUG_ON(ret);
2076 } else {
2077 BUG_ON(1);
2078 }
2079
2080 clear_extent_bits(&info->extent_ins, start, end, EXTENT_LOCKED,
2081 GFP_NOFS);
2082 kfree(extent_op);
2083 }
2084 return 0;
2085 }
2086
2087 static int pin_down_bytes(struct btrfs_trans_handle *trans,
2088 struct btrfs_root *root,
2089 u64 bytenr, u64 num_bytes, int is_data)
2090 {
2091 int err = 0;
2092 struct extent_buffer *buf;
2093
2094 if (is_data)
2095 goto pinit;
2096
2097 buf = btrfs_find_tree_block(root, bytenr, num_bytes);
2098 if (!buf)
2099 goto pinit;
2100
2101 /* we can reuse a block if it hasn't been written
2102 * and it is from this transaction. We can't
2103 * reuse anything from the tree log root because
2104 * it has tiny sub-transactions.
2105 */
2106 if (btrfs_buffer_uptodate(buf, 0)) {
2107 u64 header_owner = btrfs_header_owner(buf);
2108 u64 header_transid = btrfs_header_generation(buf);
2109 if (header_owner != BTRFS_TREE_LOG_OBJECTID &&
2110 header_transid == trans->transid &&
2111 !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
2112 clean_tree_block(NULL, root, buf);
2113 free_extent_buffer(buf);
2114 return 1;
2115 }
2116 }
2117 free_extent_buffer(buf);
2118 pinit:
2119 update_pinned_extents(root, bytenr, num_bytes, 1);
2120
2121 BUG_ON(err < 0);
2122 return 0;
2123 }
2124
2125 void btrfs_pin_extent(struct btrfs_fs_info *fs_info,
2126 u64 bytenr, u64 num_bytes)
2127 {
2128 update_pinned_extents(fs_info->extent_root, bytenr, num_bytes, 1);
2129 }
2130
2131 void btrfs_unpin_extent(struct btrfs_fs_info *fs_info,
2132 u64 bytenr, u64 num_bytes)
2133 {
2134 update_pinned_extents(fs_info->extent_root, bytenr, num_bytes, 0);
2135 }
2136
2137 /*
2138 * remove an extent from the root, returns 0 on success
2139 */
2140 static int __free_extent(struct btrfs_trans_handle *trans,
2141 struct btrfs_root *root,
2142 u64 bytenr, u64 num_bytes, u64 parent,
2143 u64 root_objectid, u64 owner_objectid,
2144 u64 owner_offset, int refs_to_drop)
2145 {
2146
2147 struct btrfs_key key;
2148 struct btrfs_path *path;
2149 struct btrfs_extent_ops *ops = root->fs_info->extent_ops;
2150 struct btrfs_root *extent_root = root->fs_info->extent_root;
2151 struct extent_buffer *leaf;
2152 struct btrfs_extent_item *ei;
2153 struct btrfs_extent_inline_ref *iref;
2154 int ret;
2155 int is_data;
2156 int extent_slot = 0;
2157 int found_extent = 0;
2158 int num_to_del = 1;
2159 u32 item_size;
2160 u64 refs;
2161 int skinny_metadata =
2162 btrfs_fs_incompat(extent_root->fs_info,
2163 BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA);
2164
2165 if (root->fs_info->free_extent_hook) {
2166 root->fs_info->free_extent_hook(trans, root, bytenr, num_bytes,
2167 parent, root_objectid, owner_objectid,
2168 owner_offset, refs_to_drop);
2169
2170 }
2171 path = btrfs_alloc_path();
2172 if (!path)
2173 return -ENOMEM;
2174
2175 path->reada = 1;
2176
2177 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
2178 if (is_data)
2179 skinny_metadata = 0;
2180 BUG_ON(!is_data && refs_to_drop != 1);
2181
2182 ret = lookup_extent_backref(trans, extent_root, path, &iref,
2183 bytenr, num_bytes, parent,
2184 root_objectid, owner_objectid,
2185 owner_offset);
2186 if (ret == 0) {
2187 extent_slot = path->slots[0];
2188 while (extent_slot >= 0) {
2189 btrfs_item_key_to_cpu(path->nodes[0], &key,
2190 extent_slot);
2191 if (key.objectid != bytenr)
2192 break;
2193 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
2194 key.offset == num_bytes) {
2195 found_extent = 1;
2196 break;
2197 }
2198 if (key.type == BTRFS_METADATA_ITEM_KEY &&
2199 key.offset == owner_objectid) {
2200 found_extent = 1;
2201 break;
2202 }
2203 if (path->slots[0] - extent_slot > 5)
2204 break;
2205 extent_slot--;
2206 }
2207 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2208 item_size = btrfs_item_size_nr(path->nodes[0], extent_slot);
2209 if (found_extent && item_size < sizeof(*ei))
2210 found_extent = 0;
2211 #endif
2212 if (!found_extent) {
2213 BUG_ON(iref);
2214 ret = remove_extent_backref(trans, extent_root, path,
2215 NULL, refs_to_drop,
2216 is_data);
2217 BUG_ON(ret);
2218 btrfs_release_path(path);
2219
2220 key.objectid = bytenr;
2221
2222 if (skinny_metadata) {
2223 key.type = BTRFS_METADATA_ITEM_KEY;
2224 key.offset = owner_objectid;
2225 } else {
2226 key.type = BTRFS_EXTENT_ITEM_KEY;
2227 key.offset = num_bytes;
2228 }
2229
2230 ret = btrfs_search_slot(trans, extent_root,
2231 &key, path, -1, 1);
2232 if (ret > 0 && skinny_metadata && path->slots[0]) {
2233 path->slots[0]--;
2234 btrfs_item_key_to_cpu(path->nodes[0],
2235 &key,
2236 path->slots[0]);
2237 if (key.objectid == bytenr &&
2238 key.type == BTRFS_EXTENT_ITEM_KEY &&
2239 key.offset == num_bytes)
2240 ret = 0;
2241 }
2242
2243 if (ret > 0 && skinny_metadata) {
2244 skinny_metadata = 0;
2245 btrfs_release_path(path);
2246 key.type = BTRFS_EXTENT_ITEM_KEY;
2247 key.offset = num_bytes;
2248 ret = btrfs_search_slot(trans, extent_root,
2249 &key, path, -1, 1);
2250 }
2251
2252 if (ret) {
2253 printk(KERN_ERR "umm, got %d back from search"
2254 ", was looking for %llu\n", ret,
2255 (unsigned long long)bytenr);
2256 btrfs_print_leaf(extent_root, path->nodes[0]);
2257 }
2258 BUG_ON(ret);
2259 extent_slot = path->slots[0];
2260 }
2261 } else {
2262 printk(KERN_ERR "btrfs unable to find ref byte nr %llu "
2263 "parent %llu root %llu owner %llu offset %llu\n",
2264 (unsigned long long)bytenr,
2265 (unsigned long long)parent,
2266 (unsigned long long)root_objectid,
2267 (unsigned long long)owner_objectid,
2268 (unsigned long long)owner_offset);
2269 ret = -EIO;
2270 goto fail;
2271 }
2272
2273 leaf = path->nodes[0];
2274 item_size = btrfs_item_size_nr(leaf, extent_slot);
2275 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2276 if (item_size < sizeof(*ei)) {
2277 BUG_ON(found_extent || extent_slot != path->slots[0]);
2278 ret = convert_extent_item_v0(trans, extent_root, path,
2279 owner_objectid, 0);
2280 BUG_ON(ret < 0);
2281
2282 btrfs_release_path(path);
2283
2284 key.objectid = bytenr;
2285 key.type = BTRFS_EXTENT_ITEM_KEY;
2286 key.offset = num_bytes;
2287
2288 ret = btrfs_search_slot(trans, extent_root, &key, path,
2289 -1, 1);
2290 if (ret) {
2291 printk(KERN_ERR "umm, got %d back from search"
2292 ", was looking for %llu\n", ret,
2293 (unsigned long long)bytenr);
2294 btrfs_print_leaf(extent_root, path->nodes[0]);
2295 }
2296 BUG_ON(ret);
2297 extent_slot = path->slots[0];
2298 leaf = path->nodes[0];
2299 item_size = btrfs_item_size_nr(leaf, extent_slot);
2300 }
2301 #endif
2302 BUG_ON(item_size < sizeof(*ei));
2303 ei = btrfs_item_ptr(leaf, extent_slot,
2304 struct btrfs_extent_item);
2305 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID &&
2306 key.type == BTRFS_EXTENT_ITEM_KEY) {
2307 struct btrfs_tree_block_info *bi;
2308 BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
2309 bi = (struct btrfs_tree_block_info *)(ei + 1);
2310 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
2311 }
2312
2313 refs = btrfs_extent_refs(leaf, ei);
2314 BUG_ON(refs < refs_to_drop);
2315 refs -= refs_to_drop;
2316
2317 if (refs > 0) {
2318 /*
2319 * In the case of inline back ref, reference count will
2320 * be updated by remove_extent_backref
2321 */
2322 if (iref) {
2323 BUG_ON(!found_extent);
2324 } else {
2325 btrfs_set_extent_refs(leaf, ei, refs);
2326 btrfs_mark_buffer_dirty(leaf);
2327 }
2328 if (found_extent) {
2329 ret = remove_extent_backref(trans, extent_root, path,
2330 iref, refs_to_drop,
2331 is_data);
2332 BUG_ON(ret);
2333 }
2334 } else {
2335 int mark_free = 0;
2336 int pin = 1;
2337
2338 if (found_extent) {
2339 BUG_ON(is_data && refs_to_drop !=
2340 extent_data_ref_count(root, path, iref));
2341 if (iref) {
2342 BUG_ON(path->slots[0] != extent_slot);
2343 } else {
2344 BUG_ON(path->slots[0] != extent_slot + 1);
2345 path->slots[0] = extent_slot;
2346 num_to_del = 2;
2347 }
2348 }
2349
2350 if (ops && ops->free_extent) {
2351 ret = ops->free_extent(root, bytenr, num_bytes);
2352 if (ret > 0) {
2353 pin = 0;
2354 mark_free = 0;
2355 }
2356 }
2357
2358 if (pin) {
2359 ret = pin_down_bytes(trans, root, bytenr, num_bytes,
2360 is_data);
2361 if (ret > 0)
2362 mark_free = 1;
2363 BUG_ON(ret < 0);
2364 }
2365
2366 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
2367 num_to_del);
2368 BUG_ON(ret);
2369 btrfs_release_path(path);
2370
2371 if (is_data) {
2372 ret = btrfs_del_csums(trans, root, bytenr, num_bytes);
2373 BUG_ON(ret);
2374 }
2375
2376 update_block_group(trans, root, bytenr, num_bytes, 0, mark_free);
2377 }
2378 fail:
2379 btrfs_free_path(path);
2380 finish_current_insert(trans, extent_root);
2381 return ret;
2382 }
2383
2384 /*
2385 * find all the blocks marked as pending in the radix tree and remove
2386 * them from the extent map
2387 */
2388 static int del_pending_extents(struct btrfs_trans_handle *trans, struct
2389 btrfs_root *extent_root)
2390 {
2391 int ret;
2392 int err = 0;
2393 u64 start;
2394 u64 end;
2395 u64 priv;
2396 struct extent_io_tree *pending_del;
2397 struct extent_io_tree *extent_ins;
2398 struct pending_extent_op *extent_op;
2399
2400 extent_ins = &extent_root->fs_info->extent_ins;
2401 pending_del = &extent_root->fs_info->pending_del;
2402
2403 while(1) {
2404 ret = find_first_extent_bit(pending_del, 0, &start, &end,
2405 EXTENT_LOCKED);
2406 if (ret)
2407 break;
2408
2409 ret = get_state_private(pending_del, start, &priv);
2410 BUG_ON(ret);
2411 extent_op = (struct pending_extent_op *)(unsigned long)priv;
2412
2413 clear_extent_bits(pending_del, start, end, EXTENT_LOCKED,
2414 GFP_NOFS);
2415
2416 if (!test_range_bit(extent_ins, start, end,
2417 EXTENT_LOCKED, 0)) {
2418 ret = __free_extent(trans, extent_root,
2419 start, end + 1 - start, 0,
2420 extent_root->root_key.objectid,
2421 extent_op->level, 0, 1);
2422 kfree(extent_op);
2423 } else {
2424 kfree(extent_op);
2425 ret = get_state_private(extent_ins, start, &priv);
2426 BUG_ON(ret);
2427 extent_op = (struct pending_extent_op *)
2428 (unsigned long)priv;
2429
2430 clear_extent_bits(extent_ins, start, end,
2431 EXTENT_LOCKED, GFP_NOFS);
2432
2433 if (extent_op->type == PENDING_BACKREF_UPDATE)
2434 BUG_ON(1);
2435
2436 kfree(extent_op);
2437 }
2438 if (ret)
2439 err = ret;
2440 }
2441 return err;
2442 }
2443
2444 /*
2445 * remove an extent from the root, returns 0 on success
2446 */
2447
2448 int btrfs_free_extent(struct btrfs_trans_handle *trans,
2449 struct btrfs_root *root,
2450 u64 bytenr, u64 num_bytes, u64 parent,
2451 u64 root_objectid, u64 owner, u64 offset)
2452 {
2453 struct btrfs_root *extent_root = root->fs_info->extent_root;
2454 int pending_ret;
2455 int ret;
2456
2457 WARN_ON(num_bytes < root->sectorsize);
2458 if (root == extent_root) {
2459 struct pending_extent_op *extent_op;
2460
2461 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
2462 BUG_ON(!extent_op);
2463
2464 extent_op->type = PENDING_EXTENT_DELETE;
2465 extent_op->bytenr = bytenr;
2466 extent_op->num_bytes = num_bytes;
2467 extent_op->level = (int)owner;
2468
2469 set_extent_bits(&root->fs_info->pending_del,
2470 bytenr, bytenr + num_bytes - 1,
2471 EXTENT_LOCKED, GFP_NOFS);
2472 set_state_private(&root->fs_info->pending_del,
2473 bytenr, (unsigned long)extent_op);
2474 return 0;
2475 }
2476 ret = __free_extent(trans, root, bytenr, num_bytes, parent,
2477 root_objectid, owner, offset, 1);
2478 pending_ret = del_pending_extents(trans, root->fs_info->extent_root);
2479 return ret ? ret : pending_ret;
2480 }
2481
2482 static u64 stripe_align(struct btrfs_root *root, u64 val)
2483 {
2484 u64 mask = ((u64)root->stripesize - 1);
2485 u64 ret = (val + mask) & ~mask;
2486 return ret;
2487 }
2488
2489 /*
2490 * walks the btree of allocated extents and find a hole of a given size.
2491 * The key ins is changed to record the hole:
2492 * ins->objectid == block start
2493 * ins->flags = BTRFS_EXTENT_ITEM_KEY
2494 * ins->offset == number of blocks
2495 * Any available blocks before search_start are skipped.
2496 */
2497 static int noinline find_free_extent(struct btrfs_trans_handle *trans,
2498 struct btrfs_root *orig_root,
2499 u64 num_bytes, u64 empty_size,
2500 u64 search_start, u64 search_end,
2501 u64 hint_byte, struct btrfs_key *ins,
2502 u64 exclude_start, u64 exclude_nr,
2503 int data)
2504 {
2505 int ret;
2506 u64 orig_search_start = search_start;
2507 struct btrfs_root * root = orig_root->fs_info->extent_root;
2508 struct btrfs_fs_info *info = root->fs_info;
2509 u64 total_needed = num_bytes;
2510 struct btrfs_block_group_cache *block_group;
2511 int full_scan = 0;
2512 int wrapped = 0;
2513
2514 WARN_ON(num_bytes < root->sectorsize);
2515 btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
2516
2517 search_start = stripe_align(root, search_start);
2518
2519 if (hint_byte) {
2520 block_group = btrfs_lookup_first_block_group(info, hint_byte);
2521 if (!block_group)
2522 hint_byte = search_start;
2523 block_group = btrfs_find_block_group(root, block_group,
2524 hint_byte, data, 1);
2525 } else {
2526 block_group = btrfs_find_block_group(root,
2527 trans->block_group,
2528 search_start, data, 1);
2529 }
2530
2531 total_needed += empty_size;
2532
2533 check_failed:
2534 search_start = stripe_align(root, search_start);
2535 if (!block_group) {
2536 block_group = btrfs_lookup_first_block_group(info,
2537 search_start);
2538 if (!block_group)
2539 block_group = btrfs_lookup_first_block_group(info,
2540 orig_search_start);
2541 }
2542 ret = find_search_start(root, &block_group, &search_start,
2543 total_needed, data);
2544 if (ret)
2545 goto new_group;
2546
2547 ins->objectid = search_start;
2548 ins->offset = num_bytes;
2549
2550 if (ins->objectid + num_bytes >
2551 block_group->key.objectid + block_group->key.offset) {
2552 search_start = block_group->key.objectid +
2553 block_group->key.offset;
2554 goto new_group;
2555 }
2556
2557 if (test_range_bit(&info->extent_ins, ins->objectid,
2558 ins->objectid + num_bytes -1, EXTENT_LOCKED, 0)) {
2559 search_start = ins->objectid + num_bytes;
2560 goto new_group;
2561 }
2562
2563 if (test_range_bit(&info->pinned_extents, ins->objectid,
2564 ins->objectid + num_bytes -1, EXTENT_DIRTY, 0)) {
2565 search_start = ins->objectid + num_bytes;
2566 goto new_group;
2567 }
2568
2569 if (exclude_nr > 0 && (ins->objectid + num_bytes > exclude_start &&
2570 ins->objectid < exclude_start + exclude_nr)) {
2571 search_start = exclude_start + exclude_nr;
2572 goto new_group;
2573 }
2574
2575 if (!(data & BTRFS_BLOCK_GROUP_DATA)) {
2576 block_group = btrfs_lookup_block_group(info, ins->objectid);
2577 if (block_group)
2578 trans->block_group = block_group;
2579 }
2580 ins->offset = num_bytes;
2581 return 0;
2582
2583 new_group:
2584 block_group = btrfs_lookup_first_block_group(info, search_start);
2585 if (!block_group) {
2586 search_start = orig_search_start;
2587 if (full_scan) {
2588 ret = -ENOSPC;
2589 goto error;
2590 }
2591 if (wrapped) {
2592 if (!full_scan)
2593 total_needed -= empty_size;
2594 full_scan = 1;
2595 } else
2596 wrapped = 1;
2597 }
2598 cond_resched();
2599 block_group = btrfs_find_block_group(root, block_group,
2600 search_start, data, 0);
2601 goto check_failed;
2602
2603 error:
2604 return ret;
2605 }
2606
2607 int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
2608 struct btrfs_root *root,
2609 u64 num_bytes, u64 empty_size,
2610 u64 hint_byte, u64 search_end,
2611 struct btrfs_key *ins, int data)
2612 {
2613 int ret;
2614 u64 search_start = 0;
2615 u64 alloc_profile;
2616 struct btrfs_fs_info *info = root->fs_info;
2617
2618 if (info->extent_ops) {
2619 struct btrfs_extent_ops *ops = info->extent_ops;
2620 ret = ops->alloc_extent(root, num_bytes, hint_byte, ins);
2621 BUG_ON(ret);
2622 goto found;
2623 }
2624
2625 if (data) {
2626 alloc_profile = info->avail_data_alloc_bits &
2627 info->data_alloc_profile;
2628 data = BTRFS_BLOCK_GROUP_DATA | alloc_profile;
2629 } else if ((info->system_allocs > 0 || root == info->chunk_root) &&
2630 info->system_allocs >= 0) {
2631 alloc_profile = info->avail_system_alloc_bits &
2632 info->system_alloc_profile;
2633 data = BTRFS_BLOCK_GROUP_SYSTEM | alloc_profile;
2634 } else {
2635 alloc_profile = info->avail_metadata_alloc_bits &
2636 info->metadata_alloc_profile;
2637 data = BTRFS_BLOCK_GROUP_METADATA | alloc_profile;
2638 }
2639
2640 if (root->ref_cows) {
2641 if (!(data & BTRFS_BLOCK_GROUP_METADATA)) {
2642 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
2643 num_bytes,
2644 BTRFS_BLOCK_GROUP_METADATA);
2645 BUG_ON(ret);
2646 }
2647 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
2648 num_bytes + 2 * 1024 * 1024, data);
2649 BUG_ON(ret);
2650 }
2651
2652 WARN_ON(num_bytes < root->sectorsize);
2653 ret = find_free_extent(trans, root, num_bytes, empty_size,
2654 search_start, search_end, hint_byte, ins,
2655 trans->alloc_exclude_start,
2656 trans->alloc_exclude_nr, data);
2657 BUG_ON(ret);
2658 found:
2659 clear_extent_dirty(&root->fs_info->free_space_cache,
2660 ins->objectid, ins->objectid + ins->offset - 1,
2661 GFP_NOFS);
2662 return ret;
2663 }
2664
2665 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
2666 struct btrfs_root *root,
2667 u64 root_objectid, u64 generation,
2668 u64 flags, struct btrfs_disk_key *key,
2669 int level, struct btrfs_key *ins)
2670 {
2671 int ret;
2672 struct btrfs_fs_info *fs_info = root->fs_info;
2673 struct btrfs_extent_item *extent_item;
2674 struct btrfs_tree_block_info *block_info;
2675 struct btrfs_extent_inline_ref *iref;
2676 struct btrfs_path *path;
2677 struct extent_buffer *leaf;
2678 u32 size = sizeof(*extent_item) + sizeof(*iref);
2679 int skinny_metadata =
2680 btrfs_fs_incompat(fs_info,
2681 BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA);
2682
2683 if (!skinny_metadata)
2684 size += sizeof(*block_info);
2685
2686 path = btrfs_alloc_path();
2687 BUG_ON(!path);
2688
2689 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
2690 ins, size);
2691 BUG_ON(ret);
2692
2693 leaf = path->nodes[0];
2694 extent_item = btrfs_item_ptr(leaf, path->slots[0],
2695 struct btrfs_extent_item);
2696 btrfs_set_extent_refs(leaf, extent_item, 1);
2697 btrfs_set_extent_generation(leaf, extent_item, generation);
2698 btrfs_set_extent_flags(leaf, extent_item,
2699 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
2700
2701 if (skinny_metadata) {
2702 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
2703 } else {
2704 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
2705 btrfs_set_tree_block_key(leaf, block_info, key);
2706 btrfs_set_tree_block_level(leaf, block_info, level);
2707 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
2708 }
2709
2710 btrfs_set_extent_inline_ref_type(leaf, iref, BTRFS_TREE_BLOCK_REF_KEY);
2711 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
2712
2713 btrfs_mark_buffer_dirty(leaf);
2714 btrfs_free_path(path);
2715
2716 ret = update_block_group(trans, root, ins->objectid, root->leafsize,
2717 1, 0);
2718 return ret;
2719 }
2720
2721 static int alloc_tree_block(struct btrfs_trans_handle *trans,
2722 struct btrfs_root *root, u64 num_bytes,
2723 u64 root_objectid, u64 generation,
2724 u64 flags, struct btrfs_disk_key *key,
2725 int level, u64 empty_size, u64 hint_byte,
2726 u64 search_end, struct btrfs_key *ins)
2727 {
2728 int ret;
2729 ret = btrfs_reserve_extent(trans, root, num_bytes, empty_size,
2730 hint_byte, search_end, ins, 0);
2731 BUG_ON(ret);
2732
2733 if (root_objectid == BTRFS_EXTENT_TREE_OBJECTID) {
2734 struct pending_extent_op *extent_op;
2735
2736 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
2737 BUG_ON(!extent_op);
2738
2739 extent_op->type = PENDING_EXTENT_INSERT;
2740 extent_op->bytenr = ins->objectid;
2741 extent_op->num_bytes = ins->offset;
2742 extent_op->level = level;
2743 extent_op->flags = flags;
2744 memcpy(&extent_op->key, key, sizeof(*key));
2745
2746 set_extent_bits(&root->fs_info->extent_ins, ins->objectid,
2747 ins->objectid + ins->offset - 1,
2748 EXTENT_LOCKED, GFP_NOFS);
2749 set_state_private(&root->fs_info->extent_ins,
2750 ins->objectid, (unsigned long)extent_op);
2751 } else {
2752 if (btrfs_fs_incompat(root->fs_info,
2753 BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA)) {
2754 ins->offset = level;
2755 ins->type = BTRFS_METADATA_ITEM_KEY;
2756 }
2757 ret = alloc_reserved_tree_block(trans, root, root_objectid,
2758 generation, flags,
2759 key, level, ins);
2760 finish_current_insert(trans, root->fs_info->extent_root);
2761 del_pending_extents(trans, root->fs_info->extent_root);
2762 }
2763 return ret;
2764 }
2765
2766 /*
2767 * helper function to allocate a block for a given tree
2768 * returns the tree buffer or NULL.
2769 */
2770 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
2771 struct btrfs_root *root,
2772 u32 blocksize, u64 root_objectid,
2773 struct btrfs_disk_key *key, int level,
2774 u64 hint, u64 empty_size)
2775 {
2776 struct btrfs_key ins;
2777 int ret;
2778 struct extent_buffer *buf;
2779
2780 ret = alloc_tree_block(trans, root, blocksize, root_objectid,
2781 trans->transid, 0, key, level,
2782 empty_size, hint, (u64)-1, &ins);
2783 if (ret) {
2784 BUG_ON(ret > 0);
2785 return ERR_PTR(ret);
2786 }
2787
2788 buf = btrfs_find_create_tree_block(root, ins.objectid, blocksize);
2789 if (!buf) {
2790 btrfs_free_extent(trans, root, ins.objectid, ins.offset,
2791 0, root->root_key.objectid, level, 0);
2792 BUG_ON(1);
2793 return ERR_PTR(-ENOMEM);
2794 }
2795 btrfs_set_buffer_uptodate(buf);
2796 trans->blocks_used++;
2797
2798 return buf;
2799 }
2800
2801 #if 0
2802
2803 static int noinline drop_leaf_ref(struct btrfs_trans_handle *trans,
2804 struct btrfs_root *root,
2805 struct extent_buffer *leaf)
2806 {
2807 u64 leaf_owner;
2808 u64 leaf_generation;
2809 struct btrfs_key key;
2810 struct btrfs_file_extent_item *fi;
2811 int i;
2812 int nritems;
2813 int ret;
2814
2815 BUG_ON(!btrfs_is_leaf(leaf));
2816 nritems = btrfs_header_nritems(leaf);
2817 leaf_owner = btrfs_header_owner(leaf);
2818 leaf_generation = btrfs_header_generation(leaf);
2819
2820 for (i = 0; i < nritems; i++) {
2821 u64 disk_bytenr;
2822
2823 btrfs_item_key_to_cpu(leaf, &key, i);
2824 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2825 continue;
2826 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
2827 if (btrfs_file_extent_type(leaf, fi) ==
2828 BTRFS_FILE_EXTENT_INLINE)
2829 continue;
2830 /*
2831 * FIXME make sure to insert a trans record that
2832 * repeats the snapshot del on crash
2833 */
2834 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
2835 if (disk_bytenr == 0)
2836 continue;
2837 ret = btrfs_free_extent(trans, root, disk_bytenr,
2838 btrfs_file_extent_disk_num_bytes(leaf, fi),
2839 leaf->start, leaf_owner, leaf_generation,
2840 key.objectid, 0);
2841 BUG_ON(ret);
2842 }
2843 return 0;
2844 }
2845
2846 static void noinline reada_walk_down(struct btrfs_root *root,
2847 struct extent_buffer *node,
2848 int slot)
2849 {
2850 u64 bytenr;
2851 u64 last = 0;
2852 u32 nritems;
2853 u32 refs;
2854 u32 blocksize;
2855 int ret;
2856 int i;
2857 int level;
2858 int skipped = 0;
2859
2860 nritems = btrfs_header_nritems(node);
2861 level = btrfs_header_level(node);
2862 if (level)
2863 return;
2864
2865 for (i = slot; i < nritems && skipped < 32; i++) {
2866 bytenr = btrfs_node_blockptr(node, i);
2867 if (last && ((bytenr > last && bytenr - last > 32 * 1024) ||
2868 (last > bytenr && last - bytenr > 32 * 1024))) {
2869 skipped++;
2870 continue;
2871 }
2872 blocksize = btrfs_level_size(root, level - 1);
2873 if (i != slot) {
2874 ret = btrfs_lookup_extent_ref(NULL, root, bytenr,
2875 blocksize, &refs);
2876 BUG_ON(ret);
2877 if (refs != 1) {
2878 skipped++;
2879 continue;
2880 }
2881 }
2882 mutex_unlock(&root->fs_info->fs_mutex);
2883 ret = readahead_tree_block(root, bytenr, blocksize,
2884 btrfs_node_ptr_generation(node, i));
2885 last = bytenr + blocksize;
2886 cond_resched();
2887 mutex_lock(&root->fs_info->fs_mutex);
2888 if (ret)
2889 break;
2890 }
2891 }
2892
2893 /*
2894 * helper function for drop_snapshot, this walks down the tree dropping ref
2895 * counts as it goes.
2896 */
2897 static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
2898 struct btrfs_root *root,
2899 struct btrfs_path *path, int *level)
2900 {
2901 u64 root_owner;
2902 u64 root_gen;
2903 u64 bytenr;
2904 u64 ptr_gen;
2905 struct extent_buffer *next;
2906 struct extent_buffer *cur;
2907 struct extent_buffer *parent;
2908 u32 blocksize;
2909 int ret;
2910 u32 refs;
2911
2912 WARN_ON(*level < 0);
2913 WARN_ON(*level >= BTRFS_MAX_LEVEL);
2914 ret = btrfs_lookup_extent_ref(trans, root,
2915 path->nodes[*level]->start,
2916 path->nodes[*level]->len, &refs);
2917 BUG_ON(ret);
2918 if (refs > 1)
2919 goto out;
2920
2921 /*
2922 * walk down to the last node level and free all the leaves
2923 */
2924 while(*level >= 0) {
2925 WARN_ON(*level < 0);
2926 WARN_ON(*level >= BTRFS_MAX_LEVEL);
2927 cur = path->nodes[*level];
2928
2929 if (btrfs_header_level(cur) != *level)
2930 WARN_ON(1);
2931
2932 if (path->slots[*level] >=
2933 btrfs_header_nritems(cur))
2934 break;
2935 if (*level == 0) {
2936 ret = drop_leaf_ref(trans, root, cur);
2937 BUG_ON(ret);
2938 break;
2939 }
2940 bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
2941 ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
2942 blocksize = btrfs_level_size(root, *level - 1);
2943 ret = btrfs_lookup_extent_ref(trans, root, bytenr, blocksize,
2944 &refs);
2945 BUG_ON(ret);
2946 if (refs != 1) {
2947 parent = path->nodes[*level];
2948 root_owner = btrfs_header_owner(parent);
2949 root_gen = btrfs_header_generation(parent);
2950 path->slots[*level]++;
2951 ret = btrfs_free_extent(trans, root, bytenr, blocksize,
2952 parent->start, root_owner,
2953 root_gen, *level - 1, 1);
2954 BUG_ON(ret);
2955 continue;
2956 }
2957 next = btrfs_find_tree_block(root, bytenr, blocksize);
2958 if (!next || !btrfs_buffer_uptodate(next, ptr_gen)) {
2959 free_extent_buffer(next);
2960 reada_walk_down(root, cur, path->slots[*level]);
2961 mutex_unlock(&root->fs_info->fs_mutex);
2962 next = read_tree_block(root, bytenr, blocksize,
2963 ptr_gen);
2964 mutex_lock(&root->fs_info->fs_mutex);
2965 }
2966 WARN_ON(*level <= 0);
2967 if (path->nodes[*level-1])
2968 free_extent_buffer(path->nodes[*level-1]);
2969 path->nodes[*level-1] = next;
2970 *level = btrfs_header_level(next);
2971 path->slots[*level] = 0;
2972 }
2973 out:
2974 WARN_ON(*level < 0);
2975 WARN_ON(*level >= BTRFS_MAX_LEVEL);
2976
2977 if (path->nodes[*level] == root->node) {
2978 root_owner = root->root_key.objectid;
2979 parent = path->nodes[*level];
2980 } else {
2981 parent = path->nodes[*level + 1];
2982 root_owner = btrfs_header_owner(parent);
2983 }
2984
2985 root_gen = btrfs_header_generation(parent);
2986 ret = btrfs_free_extent(trans, root, path->nodes[*level]->start,
2987 path->nodes[*level]->len, parent->start,
2988 root_owner, root_gen, *level, 1);
2989 free_extent_buffer(path->nodes[*level]);
2990 path->nodes[*level] = NULL;
2991 *level += 1;
2992 BUG_ON(ret);
2993 return 0;
2994 }
2995
2996 /*
2997 * helper for dropping snapshots. This walks back up the tree in the path
2998 * to find the first node higher up where we haven't yet gone through
2999 * all the slots
3000 */
3001 static int noinline walk_up_tree(struct btrfs_trans_handle *trans,
3002 struct btrfs_root *root,
3003 struct btrfs_path *path, int *level)
3004 {
3005 u64 root_owner;
3006 u64 root_gen;
3007 struct btrfs_root_item *root_item = &root->root_item;
3008 int i;
3009 int slot;
3010 int ret;
3011
3012 for(i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
3013 slot = path->slots[i];
3014 if (slot < btrfs_header_nritems(path->nodes[i]) - 1) {
3015 struct extent_buffer *node;
3016 struct btrfs_disk_key disk_key;
3017 node = path->nodes[i];
3018 path->slots[i]++;
3019 *level = i;
3020 WARN_ON(*level == 0);
3021 btrfs_node_key(node, &disk_key, path->slots[i]);
3022 memcpy(&root_item->drop_progress,
3023 &disk_key, sizeof(disk_key));
3024 root_item->drop_level = i;
3025 return 0;
3026 } else {
3027 struct extent_buffer *parent;
3028 if (path->nodes[*level] == root->node)
3029 parent = path->nodes[*level];
3030 else
3031 parent = path->nodes[*level + 1];
3032
3033 root_owner = btrfs_header_owner(parent);
3034 root_gen = btrfs_header_generation(parent);
3035 ret = btrfs_free_extent(trans, root,
3036 path->nodes[*level]->start,
3037 path->nodes[*level]->len,
3038 parent->start, root_owner,
3039 root_gen, *level, 1);
3040 BUG_ON(ret);
3041 free_extent_buffer(path->nodes[*level]);
3042 path->nodes[*level] = NULL;
3043 *level = i + 1;
3044 }
3045 }
3046 return 1;
3047 }
3048
3049 #endif
3050
3051 int btrfs_free_block_groups(struct btrfs_fs_info *info)
3052 {
3053 struct btrfs_space_info *sinfo;
3054 struct btrfs_block_group_cache *cache;
3055 u64 start;
3056 u64 end;
3057 u64 ptr;
3058 int ret;
3059
3060 while(1) {
3061 ret = find_first_extent_bit(&info->block_group_cache, 0,
3062 &start, &end, (unsigned int)-1);
3063 if (ret)
3064 break;
3065 ret = get_state_private(&info->block_group_cache, start, &ptr);
3066 if (!ret) {
3067 cache = u64_to_ptr(ptr);
3068 if (cache->free_space_ctl) {
3069 btrfs_remove_free_space_cache(cache);
3070 kfree(cache->free_space_ctl);
3071 }
3072 kfree(cache);
3073 }
3074 clear_extent_bits(&info->block_group_cache, start,
3075 end, (unsigned int)-1, GFP_NOFS);
3076 }
3077 while(1) {
3078 ret = find_first_extent_bit(&info->free_space_cache, 0,
3079 &start, &end, EXTENT_DIRTY);
3080 if (ret)
3081 break;
3082 clear_extent_dirty(&info->free_space_cache, start,
3083 end, GFP_NOFS);
3084 }
3085
3086 while (!list_empty(&info->space_info)) {
3087 sinfo = list_entry(info->space_info.next,
3088 struct btrfs_space_info, list);
3089 list_del_init(&sinfo->list);
3090 kfree(sinfo);
3091 }
3092 return 0;
3093 }
3094
3095 static int find_first_block_group(struct btrfs_root *root,
3096 struct btrfs_path *path, struct btrfs_key *key)
3097 {
3098 int ret;
3099 struct btrfs_key found_key;
3100 struct extent_buffer *leaf;
3101 int slot;
3102
3103 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
3104 if (ret < 0)
3105 return ret;
3106 while(1) {
3107 slot = path->slots[0];
3108 leaf = path->nodes[0];
3109 if (slot >= btrfs_header_nritems(leaf)) {
3110 ret = btrfs_next_leaf(root, path);
3111 if (ret == 0)
3112 continue;
3113 if (ret < 0)
3114 goto error;
3115 break;
3116 }
3117 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3118
3119 if (found_key.objectid >= key->objectid &&
3120 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY)
3121 return 0;
3122 path->slots[0]++;
3123 }
3124 ret = -ENOENT;
3125 error:
3126 return ret;
3127 }
3128
3129 int btrfs_read_block_groups(struct btrfs_root *root)
3130 {
3131 struct btrfs_path *path;
3132 int ret;
3133 int bit;
3134 struct btrfs_block_group_cache *cache;
3135 struct btrfs_fs_info *info = root->fs_info;
3136 struct btrfs_space_info *space_info;
3137 struct extent_io_tree *block_group_cache;
3138 struct btrfs_key key;
3139 struct btrfs_key found_key;
3140 struct extent_buffer *leaf;
3141
3142 block_group_cache = &info->block_group_cache;
3143
3144 root = info->extent_root;
3145 key.objectid = 0;
3146 key.offset = 0;
3147 btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
3148 path = btrfs_alloc_path();
3149 if (!path)
3150 return -ENOMEM;
3151
3152 while(1) {
3153 ret = find_first_block_group(root, path, &key);
3154 if (ret > 0) {
3155 ret = 0;
3156 goto error;
3157 }
3158 if (ret != 0) {
3159 goto error;
3160 }
3161 leaf = path->nodes[0];
3162 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3163 cache = kzalloc(sizeof(*cache), GFP_NOFS);
3164 if (!cache) {
3165 ret = -ENOMEM;
3166 break;
3167 }
3168
3169 read_extent_buffer(leaf, &cache->item,
3170 btrfs_item_ptr_offset(leaf, path->slots[0]),
3171 sizeof(cache->item));
3172 memcpy(&cache->key, &found_key, sizeof(found_key));
3173 cache->cached = 0;
3174 cache->pinned = 0;
3175 key.objectid = found_key.objectid + found_key.offset;
3176 btrfs_release_path(path);
3177 cache->flags = btrfs_block_group_flags(&cache->item);
3178 bit = 0;
3179 if (cache->flags & BTRFS_BLOCK_GROUP_DATA) {
3180 bit = BLOCK_GROUP_DATA;
3181 } else if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM) {
3182 bit = BLOCK_GROUP_SYSTEM;
3183 } else if (cache->flags & BTRFS_BLOCK_GROUP_METADATA) {
3184 bit = BLOCK_GROUP_METADATA;
3185 }
3186 set_avail_alloc_bits(info, cache->flags);
3187 if (btrfs_chunk_readonly(root, cache->key.objectid))
3188 cache->ro = 1;
3189
3190 ret = update_space_info(info, cache->flags, found_key.offset,
3191 btrfs_block_group_used(&cache->item),
3192 &space_info);
3193 BUG_ON(ret);
3194 cache->space_info = space_info;
3195
3196 /* use EXTENT_LOCKED to prevent merging */
3197 set_extent_bits(block_group_cache, found_key.objectid,
3198 found_key.objectid + found_key.offset - 1,
3199 bit | EXTENT_LOCKED, GFP_NOFS);
3200 set_state_private(block_group_cache, found_key.objectid,
3201 (unsigned long)cache);
3202 }
3203 ret = 0;
3204 error:
3205 btrfs_free_path(path);
3206 return ret;
3207 }
3208
3209 struct btrfs_block_group_cache *
3210 btrfs_add_block_group(struct btrfs_fs_info *fs_info, u64 bytes_used, u64 type,
3211 u64 chunk_objectid, u64 chunk_offset, u64 size)
3212 {
3213 int ret;
3214 int bit = 0;
3215 struct btrfs_block_group_cache *cache;
3216 struct extent_io_tree *block_group_cache;
3217
3218 block_group_cache = &fs_info->block_group_cache;
3219
3220 cache = kzalloc(sizeof(*cache), GFP_NOFS);
3221 BUG_ON(!cache);
3222 cache->key.objectid = chunk_offset;
3223 cache->key.offset = size;
3224
3225 btrfs_set_key_type(&cache->key, BTRFS_BLOCK_GROUP_ITEM_KEY);
3226 btrfs_set_block_group_used(&cache->item, bytes_used);
3227 btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
3228 cache->flags = type;
3229 btrfs_set_block_group_flags(&cache->item, type);
3230
3231 ret = update_space_info(fs_info, cache->flags, size, bytes_used,
3232 &cache->space_info);
3233 BUG_ON(ret);
3234
3235 bit = block_group_state_bits(type);
3236 ret = set_extent_bits(block_group_cache, chunk_offset,
3237 chunk_offset + size - 1,
3238 bit | EXTENT_LOCKED, GFP_NOFS);
3239 BUG_ON(ret);
3240
3241 ret = set_state_private(block_group_cache, chunk_offset,
3242 (unsigned long)cache);
3243 BUG_ON(ret);
3244 set_avail_alloc_bits(fs_info, type);
3245
3246 return cache;
3247 }
3248
3249 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
3250 struct btrfs_root *root, u64 bytes_used,
3251 u64 type, u64 chunk_objectid, u64 chunk_offset,
3252 u64 size)
3253 {
3254 int ret;
3255 struct btrfs_root *extent_root;
3256 struct btrfs_block_group_cache *cache;
3257
3258 cache = btrfs_add_block_group(root->fs_info, bytes_used, type,
3259 chunk_objectid, chunk_offset, size);
3260 extent_root = root->fs_info->extent_root;
3261 ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
3262 sizeof(cache->item));
3263 BUG_ON(ret);
3264
3265 ret = finish_current_insert(trans, extent_root);
3266 BUG_ON(ret);
3267 ret = del_pending_extents(trans, extent_root);
3268 BUG_ON(ret);
3269
3270 return 0;
3271 }
3272
3273 /*
3274 * This is for converter use only.
3275 *
3276 * In that case, we don't know where are free blocks located.
3277 * Therefore all block group cache entries must be setup properly
3278 * before doing any block allocation.
3279 */
3280 int btrfs_make_block_groups(struct btrfs_trans_handle *trans,
3281 struct btrfs_root *root)
3282 {
3283 u64 total_bytes;
3284 u64 cur_start;
3285 u64 group_type;
3286 u64 group_size;
3287 u64 group_align;
3288 u64 total_data = 0;
3289 u64 total_metadata = 0;
3290 u64 chunk_objectid;
3291 int ret;
3292 int bit;
3293 struct btrfs_root *extent_root;
3294 struct btrfs_block_group_cache *cache;
3295 struct extent_io_tree *block_group_cache;
3296
3297 extent_root = root->fs_info->extent_root;
3298 block_group_cache = &root->fs_info->block_group_cache;
3299 chunk_objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
3300 total_bytes = btrfs_super_total_bytes(root->fs_info->super_copy);
3301 group_align = 64 * root->sectorsize;
3302
3303 cur_start = 0;
3304 while (cur_start < total_bytes) {
3305 group_size = total_bytes / 12;
3306 group_size = min_t(u64, group_size, total_bytes - cur_start);
3307 if (cur_start == 0) {
3308 bit = BLOCK_GROUP_SYSTEM;
3309 group_type = BTRFS_BLOCK_GROUP_SYSTEM;
3310 group_size /= 4;
3311 group_size &= ~(group_align - 1);
3312 group_size = max_t(u64, group_size, 8 * 1024 * 1024);
3313 group_size = min_t(u64, group_size, 32 * 1024 * 1024);
3314 } else {
3315 group_size &= ~(group_align - 1);
3316 if (total_data >= total_metadata * 2) {
3317 group_type = BTRFS_BLOCK_GROUP_METADATA;
3318 group_size = min_t(u64, group_size,
3319 1ULL * 1024 * 1024 * 1024);
3320 total_metadata += group_size;
3321 } else {
3322 group_type = BTRFS_BLOCK_GROUP_DATA;
3323 group_size = min_t(u64, group_size,
3324 5ULL * 1024 * 1024 * 1024);
3325 total_data += group_size;
3326 }
3327 if ((total_bytes - cur_start) * 4 < group_size * 5)
3328 group_size = total_bytes - cur_start;
3329 }
3330
3331 cache = kzalloc(sizeof(*cache), GFP_NOFS);
3332 BUG_ON(!cache);
3333
3334 cache->key.objectid = cur_start;
3335 cache->key.offset = group_size;
3336 btrfs_set_key_type(&cache->key, BTRFS_BLOCK_GROUP_ITEM_KEY);
3337
3338 btrfs_set_block_group_used(&cache->item, 0);
3339 btrfs_set_block_group_chunk_objectid(&cache->item,
3340 chunk_objectid);
3341 btrfs_set_block_group_flags(&cache->item, group_type);
3342
3343 cache->flags = group_type;
3344
3345 ret = update_space_info(root->fs_info, group_type, group_size,
3346 0, &cache->space_info);
3347 BUG_ON(ret);
3348 set_avail_alloc_bits(extent_root->fs_info, group_type);
3349
3350 set_extent_bits(block_group_cache, cur_start,
3351 cur_start + group_size - 1,
3352 bit | EXTENT_LOCKED, GFP_NOFS);
3353 set_state_private(block_group_cache, cur_start,
3354 (unsigned long)cache);
3355 cur_start += group_size;
3356 }
3357 /* then insert all the items */
3358 cur_start = 0;
3359 while(cur_start < total_bytes) {
3360 cache = btrfs_lookup_block_group(root->fs_info, cur_start);
3361 BUG_ON(!cache);
3362
3363 ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
3364 sizeof(cache->item));
3365 BUG_ON(ret);
3366
3367 finish_current_insert(trans, extent_root);
3368 ret = del_pending_extents(trans, extent_root);
3369 BUG_ON(ret);
3370
3371 cur_start = cache->key.objectid + cache->key.offset;
3372 }
3373 return 0;
3374 }
3375
3376 int btrfs_update_block_group(struct btrfs_trans_handle *trans,
3377 struct btrfs_root *root,
3378 u64 bytenr, u64 num_bytes, int alloc,
3379 int mark_free)
3380 {
3381 return update_block_group(trans, root, bytenr, num_bytes,
3382 alloc, mark_free);
3383 }
3384
3385 /*
3386 * Fixup block accounting. The initial block accounting created by
3387 * make_block_groups isn't accuracy in this case.
3388 */
3389 int btrfs_fix_block_accounting(struct btrfs_trans_handle *trans,
3390 struct btrfs_root *root)
3391 {
3392 int ret;
3393 int slot;
3394 u64 start = 0;
3395 u64 bytes_used = 0;
3396 struct btrfs_path path;
3397 struct btrfs_key key;
3398 struct extent_buffer *leaf;
3399 struct btrfs_block_group_cache *cache;
3400 struct btrfs_fs_info *fs_info = root->fs_info;
3401
3402 root = root->fs_info->extent_root;
3403
3404 while(extent_root_pending_ops(fs_info)) {
3405 ret = finish_current_insert(trans, root);
3406 if (ret)
3407 return ret;
3408 ret = del_pending_extents(trans, root);
3409 if (ret)
3410 return ret;
3411 }
3412
3413 while(1) {
3414 cache = btrfs_lookup_first_block_group(fs_info, start);
3415 if (!cache)
3416 break;
3417 start = cache->key.objectid + cache->key.offset;
3418 btrfs_set_block_group_used(&cache->item, 0);
3419 cache->space_info->bytes_used = 0;
3420 set_extent_bits(&root->fs_info->block_group_cache,
3421 cache->key.objectid,
3422 cache->key.objectid + cache->key.offset -1,
3423 BLOCK_GROUP_DIRTY, GFP_NOFS);
3424 }
3425
3426 btrfs_init_path(&path);
3427 key.offset = 0;
3428 key.objectid = 0;
3429 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
3430 ret = btrfs_search_slot(trans, root->fs_info->extent_root,
3431 &key, &path, 0, 0);
3432 if (ret < 0)
3433 return ret;
3434 while(1) {
3435 leaf = path.nodes[0];
3436 slot = path.slots[0];
3437 if (slot >= btrfs_header_nritems(leaf)) {
3438 ret = btrfs_next_leaf(root, &path);
3439 if (ret < 0)
3440 return ret;
3441 if (ret > 0)
3442 break;
3443 leaf = path.nodes[0];
3444 slot = path.slots[0];
3445 }
3446 btrfs_item_key_to_cpu(leaf, &key, slot);
3447 if (key.type == BTRFS_EXTENT_ITEM_KEY) {
3448 bytes_used += key.offset;
3449 ret = btrfs_update_block_group(trans, root,
3450 key.objectid, key.offset, 1, 0);
3451 BUG_ON(ret);
3452 } else if (key.type == BTRFS_METADATA_ITEM_KEY) {
3453 bytes_used += root->leafsize;
3454 ret = btrfs_update_block_group(trans, root,
3455 key.objectid, root->leafsize, 1, 0);
3456 BUG_ON(ret);
3457 }
3458 path.slots[0]++;
3459 }
3460 btrfs_set_super_bytes_used(root->fs_info->super_copy, bytes_used);
3461 btrfs_release_path(&path);
3462 return 0;
3463 }
3464
3465 /*
3466 * Record a file extent. Do all the required works, such as inserting
3467 * file extent item, inserting extent item and backref item into extent
3468 * tree and updating block accounting.
3469 */
3470 int btrfs_record_file_extent(struct btrfs_trans_handle *trans,
3471 struct btrfs_root *root, u64 objectid,
3472 struct btrfs_inode_item *inode,
3473 u64 file_pos, u64 disk_bytenr,
3474 u64 num_bytes)
3475 {
3476 int ret;
3477 struct btrfs_fs_info *info = root->fs_info;
3478 struct btrfs_root *extent_root = info->extent_root;
3479 struct extent_buffer *leaf;
3480 struct btrfs_file_extent_item *fi;
3481 struct btrfs_key ins_key;
3482 struct btrfs_path path;
3483 struct btrfs_extent_item *ei;
3484 u64 nbytes;
3485
3486 if (disk_bytenr == 0) {
3487 ret = btrfs_insert_file_extent(trans, root, objectid,
3488 file_pos, disk_bytenr,
3489 num_bytes, num_bytes);
3490 return ret;
3491 }
3492
3493 btrfs_init_path(&path);
3494
3495 ins_key.objectid = objectid;
3496 ins_key.offset = file_pos;
3497 btrfs_set_key_type(&ins_key, BTRFS_EXTENT_DATA_KEY);
3498 ret = btrfs_insert_empty_item(trans, root, &path, &ins_key,
3499 sizeof(*fi));
3500 if (ret)
3501 goto fail;
3502 leaf = path.nodes[0];
3503 fi = btrfs_item_ptr(leaf, path.slots[0],
3504 struct btrfs_file_extent_item);
3505 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
3506 btrfs_set_file_extent_type(leaf, fi, BTRFS_FILE_EXTENT_REG);
3507 btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr);
3508 btrfs_set_file_extent_disk_num_bytes(leaf, fi, num_bytes);
3509 btrfs_set_file_extent_offset(leaf, fi, 0);
3510 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
3511 btrfs_set_file_extent_ram_bytes(leaf, fi, num_bytes);
3512 btrfs_set_file_extent_compression(leaf, fi, 0);
3513 btrfs_set_file_extent_encryption(leaf, fi, 0);
3514 btrfs_set_file_extent_other_encoding(leaf, fi, 0);
3515 btrfs_mark_buffer_dirty(leaf);
3516
3517 nbytes = btrfs_stack_inode_nbytes(inode) + num_bytes;
3518 btrfs_set_stack_inode_nbytes(inode, nbytes);
3519
3520 btrfs_release_path(&path);
3521
3522 ins_key.objectid = disk_bytenr;
3523 ins_key.offset = num_bytes;
3524 ins_key.type = BTRFS_EXTENT_ITEM_KEY;
3525
3526 ret = btrfs_insert_empty_item(trans, extent_root, &path,
3527 &ins_key, sizeof(*ei));
3528 if (ret == 0) {
3529 leaf = path.nodes[0];
3530 ei = btrfs_item_ptr(leaf, path.slots[0],
3531 struct btrfs_extent_item);
3532
3533 btrfs_set_extent_refs(leaf, ei, 0);
3534 btrfs_set_extent_generation(leaf, ei, 0);
3535 btrfs_set_extent_flags(leaf, ei, BTRFS_EXTENT_FLAG_DATA);
3536
3537 btrfs_mark_buffer_dirty(leaf);
3538
3539 ret = btrfs_update_block_group(trans, root, disk_bytenr,
3540 num_bytes, 1, 0);
3541 if (ret)
3542 goto fail;
3543 } else if (ret != -EEXIST) {
3544 goto fail;
3545 }
3546 btrfs_extent_post_op(trans, extent_root);
3547
3548 ret = btrfs_inc_extent_ref(trans, root, disk_bytenr, num_bytes, 0,
3549 root->root_key.objectid,
3550 objectid, file_pos);
3551 if (ret)
3552 goto fail;
3553 ret = 0;
3554 fail:
3555 btrfs_release_path(&path);
3556 return ret;
3557 }
(deprecated) Btrfs progs developments and patch integration