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btrfs-progs: Remove duplicate printfs in warning_trace()/assert_trace()
[btrfs-progs-unstable/devel.git] / extent-tree.c
blobb2847ff9041640396307c644e9ef8a9732157f1f
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 <math.h>
23 #include "kerncompat.h"
24 #include "radix-tree.h"
25 #include "ctree.h"
26 #include "disk-io.h"
27 #include "print-tree.h"
28 #include "transaction.h"
29 #include "crc32c.h"
30 #include "volumes.h"
31 #include "free-space-cache.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->nodesize;
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 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, SKINNY_METADATA);
999
1000 key.objectid = bytenr;
1001 key.type = BTRFS_EXTENT_ITEM_KEY;
1002 key.offset = num_bytes;
1003
1004 want = extent_ref_type(parent, owner);
1005 if (insert)
1006 extra_size = btrfs_extent_inline_ref_size(want);
1007 else
1008 extra_size = -1;
1009
1010 if (owner < BTRFS_FIRST_FREE_OBJECTID && skinny_metadata) {
1011 skinny_metadata = 1;
1012 key.type = BTRFS_METADATA_ITEM_KEY;
1013 key.offset = owner;
1014 } else if (skinny_metadata) {
1015 skinny_metadata = 0;
1016 }
1017
1018 again:
1019 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
1020 if (ret < 0) {
1021 err = ret;
1022 goto out;
1023 }
1024
1025 /*
1026 * We may be a newly converted file system which still has the old fat
1027 * extent entries for metadata, so try and see if we have one of those.
1028 */
1029 if (ret > 0 && skinny_metadata) {
1030 skinny_metadata = 0;
1031 if (path->slots[0]) {
1032 path->slots[0]--;
1033 btrfs_item_key_to_cpu(path->nodes[0], &key,
1034 path->slots[0]);
1035 if (key.objectid == bytenr &&
1036 key.type == BTRFS_EXTENT_ITEM_KEY &&
1037 key.offset == num_bytes)
1038 ret = 0;
1039 }
1040 if (ret) {
1041 key.type = BTRFS_EXTENT_ITEM_KEY;
1042 key.offset = num_bytes;
1043 btrfs_release_path(path);
1044 goto again;
1045 }
1046 }
1047
1048 if (ret) {
1049 printf("Failed to find [%llu, %u, %llu]\n", key.objectid, key.type, key.offset);
1050 return -ENOENT;
1051 }
1052
1053 BUG_ON(ret);
1054
1055 leaf = path->nodes[0];
1056 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1057 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1058 if (item_size < sizeof(*ei)) {
1059 if (!insert) {
1060 err = -ENOENT;
1061 goto out;
1062 }
1063 ret = convert_extent_item_v0(trans, root, path, owner,
1064 extra_size);
1065 if (ret < 0) {
1066 err = ret;
1067 goto out;
1068 }
1069 leaf = path->nodes[0];
1070 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1071 }
1072 #endif
1073 if (item_size < sizeof(*ei)) {
1074 printf("Size is %u, needs to be %u, slot %d\n",
1075 (unsigned)item_size,
1076 (unsigned)sizeof(*ei), path->slots[0]);
1077 btrfs_print_leaf(root, leaf);
1078 return -EINVAL;
1079 }
1080 BUG_ON(item_size < sizeof(*ei));
1081
1082 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1083 flags = btrfs_extent_flags(leaf, ei);
1084
1085 ptr = (unsigned long)(ei + 1);
1086 end = (unsigned long)ei + item_size;
1087
1088 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK && !skinny_metadata) {
1089 ptr += sizeof(struct btrfs_tree_block_info);
1090 BUG_ON(ptr > end);
1091 } else if (!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) {
1092 if (!(flags & BTRFS_EXTENT_FLAG_DATA)) {
1093 return -EIO;
1094 }
1095 }
1096
1097 err = -ENOENT;
1098 while (1) {
1099 if (ptr >= end) {
1100 WARN_ON(ptr > end);
1101 break;
1102 }
1103 iref = (struct btrfs_extent_inline_ref *)ptr;
1104 type = btrfs_extent_inline_ref_type(leaf, iref);
1105 if (want < type)
1106 break;
1107 if (want > type) {
1108 ptr += btrfs_extent_inline_ref_size(type);
1109 continue;
1110 }
1111
1112 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1113 struct btrfs_extent_data_ref *dref;
1114 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1115 if (match_extent_data_ref(leaf, dref, root_objectid,
1116 owner, offset)) {
1117 err = 0;
1118 break;
1119 }
1120 if (hash_extent_data_ref_item(leaf, dref) <
1121 hash_extent_data_ref(root_objectid, owner, offset))
1122 break;
1123 } else {
1124 u64 ref_offset;
1125 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1126 if (parent > 0) {
1127 if (parent == ref_offset) {
1128 err = 0;
1129 break;
1130 }
1131 if (ref_offset < parent)
1132 break;
1133 } else {
1134 if (root_objectid == ref_offset) {
1135 err = 0;
1136 break;
1137 }
1138 if (ref_offset < root_objectid)
1139 break;
1140 }
1141 }
1142 ptr += btrfs_extent_inline_ref_size(type);
1143 }
1144 if (err == -ENOENT && insert) {
1145 if (item_size + extra_size >=
1146 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
1147 err = -EAGAIN;
1148 goto out;
1149 }
1150 /*
1151 * To add new inline back ref, we have to make sure
1152 * there is no corresponding back ref item.
1153 * For simplicity, we just do not add new inline back
1154 * ref if there is any back ref item.
1155 */
1156 if (find_next_key(path, &key) == 0 && key.objectid == bytenr &&
1157 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
1158 err = -EAGAIN;
1159 goto out;
1160 }
1161 }
1162 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
1163 out:
1164 return err;
1165 }
1166
1167 static int setup_inline_extent_backref(struct btrfs_trans_handle *trans,
1168 struct btrfs_root *root,
1169 struct btrfs_path *path,
1170 struct btrfs_extent_inline_ref *iref,
1171 u64 parent, u64 root_objectid,
1172 u64 owner, u64 offset, int refs_to_add)
1173 {
1174 struct extent_buffer *leaf;
1175 struct btrfs_extent_item *ei;
1176 unsigned long ptr;
1177 unsigned long end;
1178 unsigned long item_offset;
1179 u64 refs;
1180 int size;
1181 int type;
1182 int ret;
1183
1184 leaf = path->nodes[0];
1185 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1186 item_offset = (unsigned long)iref - (unsigned long)ei;
1187
1188 type = extent_ref_type(parent, owner);
1189 size = btrfs_extent_inline_ref_size(type);
1190
1191 ret = btrfs_extend_item(trans, root, path, size);
1192 BUG_ON(ret);
1193
1194 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1195 refs = btrfs_extent_refs(leaf, ei);
1196 refs += refs_to_add;
1197 btrfs_set_extent_refs(leaf, ei, refs);
1198
1199 ptr = (unsigned long)ei + item_offset;
1200 end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
1201 if (ptr < end - size)
1202 memmove_extent_buffer(leaf, ptr + size, ptr,
1203 end - size - ptr);
1204
1205 iref = (struct btrfs_extent_inline_ref *)ptr;
1206 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1207 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1208 struct btrfs_extent_data_ref *dref;
1209 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1210 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1211 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1212 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1213 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1214 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1215 struct btrfs_shared_data_ref *sref;
1216 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1217 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1218 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1219 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1220 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1221 } else {
1222 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1223 }
1224 btrfs_mark_buffer_dirty(leaf);
1225 return 0;
1226 }
1227
1228 static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1229 struct btrfs_root *root,
1230 struct btrfs_path *path,
1231 struct btrfs_extent_inline_ref **ref_ret,
1232 u64 bytenr, u64 num_bytes, u64 parent,
1233 u64 root_objectid, u64 owner, u64 offset)
1234 {
1235 int ret;
1236
1237 ret = lookup_inline_extent_backref(trans, root, path, ref_ret,
1238 bytenr, num_bytes, parent,
1239 root_objectid, owner, offset, 0);
1240 if (ret != -ENOENT)
1241 return ret;
1242
1243 btrfs_release_path(path);
1244 *ref_ret = NULL;
1245
1246 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1247 ret = lookup_tree_block_ref(trans, root, path, bytenr, parent,
1248 root_objectid);
1249 } else {
1250 ret = lookup_extent_data_ref(trans, root, path, bytenr, parent,
1251 root_objectid, owner, offset);
1252 }
1253 return ret;
1254 }
1255
1256 static int update_inline_extent_backref(struct btrfs_trans_handle *trans,
1257 struct btrfs_root *root,
1258 struct btrfs_path *path,
1259 struct btrfs_extent_inline_ref *iref,
1260 int refs_to_mod)
1261 {
1262 struct extent_buffer *leaf;
1263 struct btrfs_extent_item *ei;
1264 struct btrfs_extent_data_ref *dref = NULL;
1265 struct btrfs_shared_data_ref *sref = NULL;
1266 unsigned long ptr;
1267 unsigned long end;
1268 u32 item_size;
1269 int size;
1270 int type;
1271 int ret;
1272 u64 refs;
1273
1274 leaf = path->nodes[0];
1275 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1276 refs = btrfs_extent_refs(leaf, ei);
1277 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1278 refs += refs_to_mod;
1279 btrfs_set_extent_refs(leaf, ei, refs);
1280
1281 type = btrfs_extent_inline_ref_type(leaf, iref);
1282
1283 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1284 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1285 refs = btrfs_extent_data_ref_count(leaf, dref);
1286 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1287 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1288 refs = btrfs_shared_data_ref_count(leaf, sref);
1289 } else {
1290 refs = 1;
1291 BUG_ON(refs_to_mod != -1);
1292 }
1293
1294 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1295 refs += refs_to_mod;
1296
1297 if (refs > 0) {
1298 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1299 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1300 else
1301 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1302 } else {
1303 size = btrfs_extent_inline_ref_size(type);
1304 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1305 ptr = (unsigned long)iref;
1306 end = (unsigned long)ei + item_size;
1307 if (ptr + size < end)
1308 memmove_extent_buffer(leaf, ptr, ptr + size,
1309 end - ptr - size);
1310 item_size -= size;
1311 ret = btrfs_truncate_item(trans, root, path, item_size, 1);
1312 BUG_ON(ret);
1313 }
1314 btrfs_mark_buffer_dirty(leaf);
1315 return 0;
1316 }
1317
1318 static int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1319 struct btrfs_root *root,
1320 struct btrfs_path *path,
1321 u64 bytenr, u64 num_bytes, u64 parent,
1322 u64 root_objectid, u64 owner,
1323 u64 offset, int refs_to_add)
1324 {
1325 struct btrfs_extent_inline_ref *iref;
1326 int ret;
1327
1328 ret = lookup_inline_extent_backref(trans, root, path, &iref,
1329 bytenr, num_bytes, parent,
1330 root_objectid, owner, offset, 1);
1331 if (ret == 0) {
1332 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
1333 ret = update_inline_extent_backref(trans, root, path, iref,
1334 refs_to_add);
1335 } else if (ret == -ENOENT) {
1336 ret = setup_inline_extent_backref(trans, root, path, iref,
1337 parent, root_objectid,
1338 owner, offset, refs_to_add);
1339 }
1340 return ret;
1341 }
1342
1343 static int insert_extent_backref(struct btrfs_trans_handle *trans,
1344 struct btrfs_root *root,
1345 struct btrfs_path *path,
1346 u64 bytenr, u64 parent, u64 root_objectid,
1347 u64 owner, u64 offset, int refs_to_add)
1348 {
1349 int ret;
1350
1351 if (owner >= BTRFS_FIRST_FREE_OBJECTID) {
1352 ret = insert_extent_data_ref(trans, root, path, bytenr,
1353 parent, root_objectid,
1354 owner, offset, refs_to_add);
1355 } else {
1356 BUG_ON(refs_to_add != 1);
1357 ret = insert_tree_block_ref(trans, root, path, bytenr,
1358 parent, root_objectid);
1359 }
1360 return ret;
1361 }
1362
1363 static int remove_extent_backref(struct btrfs_trans_handle *trans,
1364 struct btrfs_root *root,
1365 struct btrfs_path *path,
1366 struct btrfs_extent_inline_ref *iref,
1367 int refs_to_drop, int is_data)
1368 {
1369 int ret;
1370
1371 BUG_ON(!is_data && refs_to_drop != 1);
1372 if (iref) {
1373 ret = update_inline_extent_backref(trans, root, path, iref,
1374 -refs_to_drop);
1375 } else if (is_data) {
1376 ret = remove_extent_data_ref(trans, root, path, refs_to_drop);
1377 } else {
1378 ret = btrfs_del_item(trans, root, path);
1379 }
1380 return ret;
1381 }
1382
1383 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1384 struct btrfs_root *root,
1385 u64 bytenr, u64 num_bytes, u64 parent,
1386 u64 root_objectid, u64 owner, u64 offset)
1387 {
1388 struct btrfs_path *path;
1389 struct extent_buffer *leaf;
1390 struct btrfs_extent_item *item;
1391 u64 refs;
1392 int ret;
1393 int err = 0;
1394
1395 path = btrfs_alloc_path();
1396 if (!path)
1397 return -ENOMEM;
1398
1399 path->reada = 1;
1400
1401 ret = insert_inline_extent_backref(trans, root->fs_info->extent_root,
1402 path, bytenr, num_bytes, parent,
1403 root_objectid, owner, offset, 1);
1404 if (ret == 0)
1405 goto out;
1406
1407 if (ret != -EAGAIN) {
1408 err = ret;
1409 goto out;
1410 }
1411
1412 leaf = path->nodes[0];
1413 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1414 refs = btrfs_extent_refs(leaf, item);
1415 btrfs_set_extent_refs(leaf, item, refs + 1);
1416
1417 btrfs_mark_buffer_dirty(leaf);
1418 btrfs_release_path(path);
1419
1420 path->reada = 1;
1421
1422 /* now insert the actual backref */
1423 ret = insert_extent_backref(trans, root->fs_info->extent_root,
1424 path, bytenr, parent, root_objectid,
1425 owner, offset, 1);
1426 if (ret)
1427 err = ret;
1428 out:
1429 btrfs_free_path(path);
1430 finish_current_insert(trans, root->fs_info->extent_root);
1431 del_pending_extents(trans, root->fs_info->extent_root);
1432 BUG_ON(err);
1433 return err;
1434 }
1435
1436 int btrfs_extent_post_op(struct btrfs_trans_handle *trans,
1437 struct btrfs_root *root)
1438 {
1439 finish_current_insert(trans, root->fs_info->extent_root);
1440 del_pending_extents(trans, root->fs_info->extent_root);
1441 return 0;
1442 }
1443
1444 int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
1445 struct btrfs_root *root, u64 bytenr,
1446 u64 offset, int metadata, u64 *refs, u64 *flags)
1447 {
1448 struct btrfs_path *path;
1449 int ret;
1450 struct btrfs_key key;
1451 struct extent_buffer *l;
1452 struct btrfs_extent_item *item;
1453 u32 item_size;
1454 u64 num_refs;
1455 u64 extent_flags;
1456
1457 if (metadata &&
1458 !btrfs_fs_incompat(root->fs_info, SKINNY_METADATA)) {
1459 offset = root->nodesize;
1460 metadata = 0;
1461 }
1462
1463 path = btrfs_alloc_path();
1464 if (!path)
1465 return -ENOMEM;
1466 path->reada = 1;
1467
1468 key.objectid = bytenr;
1469 key.offset = offset;
1470 if (metadata)
1471 key.type = BTRFS_METADATA_ITEM_KEY;
1472 else
1473 key.type = BTRFS_EXTENT_ITEM_KEY;
1474
1475 again:
1476 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path,
1477 0, 0);
1478 if (ret < 0)
1479 goto out;
1480
1481 /*
1482 * Deal with the fact that we may have mixed SKINNY and normal refs. If
1483 * we didn't find what we wanted check and see if we have a normal ref
1484 * right next to us, or re-search if we are on the edge of the leaf just
1485 * to make sure.
1486 */
1487 if (ret > 0 && metadata) {
1488 if (path->slots[0]) {
1489 path->slots[0]--;
1490 btrfs_item_key_to_cpu(path->nodes[0], &key,
1491 path->slots[0]);
1492 if (key.objectid == bytenr &&
1493 key.type == BTRFS_EXTENT_ITEM_KEY &&
1494 key.offset == root->nodesize)
1495 ret = 0;
1496 }
1497
1498 if (ret) {
1499 btrfs_release_path(path);
1500 key.type = BTRFS_EXTENT_ITEM_KEY;
1501 key.offset = root->nodesize;
1502 metadata = 0;
1503 goto again;
1504 }
1505 }
1506
1507 if (ret != 0) {
1508 ret = -EIO;
1509 goto out;
1510 }
1511
1512 l = path->nodes[0];
1513 item_size = btrfs_item_size_nr(l, path->slots[0]);
1514 if (item_size >= sizeof(*item)) {
1515 item = btrfs_item_ptr(l, path->slots[0],
1516 struct btrfs_extent_item);
1517 num_refs = btrfs_extent_refs(l, item);
1518 extent_flags = btrfs_extent_flags(l, item);
1519 } else {
1520 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1521 struct btrfs_extent_item_v0 *ei0;
1522 BUG_ON(item_size != sizeof(*ei0));
1523 ei0 = btrfs_item_ptr(l, path->slots[0],
1524 struct btrfs_extent_item_v0);
1525 num_refs = btrfs_extent_refs_v0(l, ei0);
1526 /* FIXME: this isn't correct for data */
1527 extent_flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
1528 #else
1529 BUG();
1530 #endif
1531 }
1532 item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
1533 if (refs)
1534 *refs = num_refs;
1535 if (flags)
1536 *flags = extent_flags;
1537 out:
1538 btrfs_free_path(path);
1539 return ret;
1540 }
1541
1542 int btrfs_set_block_flags(struct btrfs_trans_handle *trans,
1543 struct btrfs_root *root,
1544 u64 bytenr, int level, u64 flags)
1545 {
1546 struct btrfs_path *path;
1547 int ret;
1548 struct btrfs_key key;
1549 struct extent_buffer *l;
1550 struct btrfs_extent_item *item;
1551 u32 item_size;
1552 int skinny_metadata =
1553 btrfs_fs_incompat(root->fs_info, SKINNY_METADATA);
1554
1555 path = btrfs_alloc_path();
1556 if (!path)
1557 return -ENOMEM;
1558 path->reada = 1;
1559
1560 key.objectid = bytenr;
1561 if (skinny_metadata) {
1562 key.offset = level;
1563 key.type = BTRFS_METADATA_ITEM_KEY;
1564 } else {
1565 key.offset = root->nodesize;
1566 key.type = BTRFS_EXTENT_ITEM_KEY;
1567 }
1568
1569 again:
1570 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path,
1571 0, 0);
1572 if (ret < 0)
1573 goto out;
1574
1575 if (ret > 0 && skinny_metadata) {
1576 skinny_metadata = 0;
1577 if (path->slots[0]) {
1578 path->slots[0]--;
1579 btrfs_item_key_to_cpu(path->nodes[0], &key,
1580 path->slots[0]);
1581 if (key.objectid == bytenr &&
1582 key.offset == root->nodesize &&
1583 key.type == BTRFS_EXTENT_ITEM_KEY)
1584 ret = 0;
1585 }
1586 if (ret) {
1587 btrfs_release_path(path);
1588 key.offset = root->nodesize;
1589 key.type = BTRFS_EXTENT_ITEM_KEY;
1590 goto again;
1591 }
1592 }
1593
1594 if (ret != 0) {
1595 btrfs_print_leaf(root, path->nodes[0]);
1596 printk("failed to find block number %Lu\n",
1597 (unsigned long long)bytenr);
1598 BUG();
1599 }
1600 l = path->nodes[0];
1601 item_size = btrfs_item_size_nr(l, path->slots[0]);
1602 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1603 if (item_size < sizeof(*item)) {
1604 ret = convert_extent_item_v0(trans, root->fs_info->extent_root,
1605 path, (u64)-1, 0);
1606 if (ret < 0)
1607 goto out;
1608
1609 l = path->nodes[0];
1610 item_size = btrfs_item_size_nr(l, path->slots[0]);
1611 }
1612 #endif
1613 BUG_ON(item_size < sizeof(*item));
1614 item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
1615 flags |= btrfs_extent_flags(l, item);
1616 btrfs_set_extent_flags(l, item, flags);
1617 out:
1618 btrfs_free_path(path);
1619 finish_current_insert(trans, root->fs_info->extent_root);
1620 del_pending_extents(trans, root->fs_info->extent_root);
1621 return ret;
1622 }
1623
1624 static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
1625 struct btrfs_root *root,
1626 struct extent_buffer *buf,
1627 int record_parent, int inc)
1628 {
1629 u64 bytenr;
1630 u64 num_bytes;
1631 u64 parent;
1632 u64 ref_root;
1633 u32 nritems;
1634 struct btrfs_key key;
1635 struct btrfs_file_extent_item *fi;
1636 int i;
1637 int level;
1638 int ret = 0;
1639 int (*process_func)(struct btrfs_trans_handle *trans,
1640 struct btrfs_root *root,
1641 u64, u64, u64, u64, u64, u64);
1642
1643 ref_root = btrfs_header_owner(buf);
1644 nritems = btrfs_header_nritems(buf);
1645 level = btrfs_header_level(buf);
1646
1647 if (!root->ref_cows && level == 0)
1648 return 0;
1649
1650 if (inc)
1651 process_func = btrfs_inc_extent_ref;
1652 else
1653 process_func = btrfs_free_extent;
1654
1655 if (record_parent)
1656 parent = buf->start;
1657 else
1658 parent = 0;
1659
1660 for (i = 0; i < nritems; i++) {
1661 cond_resched();
1662 if (level == 0) {
1663 btrfs_item_key_to_cpu(buf, &key, i);
1664 if (key.type != BTRFS_EXTENT_DATA_KEY)
1665 continue;
1666 fi = btrfs_item_ptr(buf, i,
1667 struct btrfs_file_extent_item);
1668 if (btrfs_file_extent_type(buf, fi) ==
1669 BTRFS_FILE_EXTENT_INLINE)
1670 continue;
1671 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
1672 if (bytenr == 0)
1673 continue;
1674
1675 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
1676 key.offset -= btrfs_file_extent_offset(buf, fi);
1677 ret = process_func(trans, root, bytenr, num_bytes,
1678 parent, ref_root, key.objectid,
1679 key.offset);
1680 if (ret) {
1681 WARN_ON(1);
1682 goto fail;
1683 }
1684 } else {
1685 bytenr = btrfs_node_blockptr(buf, i);
1686 num_bytes = root->nodesize;
1687 ret = process_func(trans, root, bytenr, num_bytes,
1688 parent, ref_root, level - 1, 0);
1689 if (ret) {
1690 WARN_ON(1);
1691 goto fail;
1692 }
1693 }
1694 }
1695 return 0;
1696 fail:
1697 WARN_ON(1);
1698 return ret;
1699 }
1700
1701 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
1702 struct extent_buffer *buf, int record_parent)
1703 {
1704 return __btrfs_mod_ref(trans, root, buf, record_parent, 1);
1705 }
1706
1707 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
1708 struct extent_buffer *buf, int record_parent)
1709 {
1710 return __btrfs_mod_ref(trans, root, buf, record_parent, 0);
1711 }
1712
1713 static int write_one_cache_group(struct btrfs_trans_handle *trans,
1714 struct btrfs_root *root,
1715 struct btrfs_path *path,
1716 struct btrfs_block_group_cache *cache)
1717 {
1718 int ret;
1719 int pending_ret;
1720 struct btrfs_root *extent_root = root->fs_info->extent_root;
1721 unsigned long bi;
1722 struct extent_buffer *leaf;
1723
1724 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
1725 if (ret < 0)
1726 goto fail;
1727 BUG_ON(ret);
1728
1729 leaf = path->nodes[0];
1730 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
1731 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
1732 btrfs_mark_buffer_dirty(leaf);
1733 btrfs_release_path(path);
1734 fail:
1735 finish_current_insert(trans, extent_root);
1736 pending_ret = del_pending_extents(trans, extent_root);
1737 if (ret)
1738 return ret;
1739 if (pending_ret)
1740 return pending_ret;
1741 return 0;
1742
1743 }
1744
1745 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
1746 struct btrfs_root *root)
1747 {
1748 struct extent_io_tree *block_group_cache;
1749 struct btrfs_block_group_cache *cache;
1750 int ret;
1751 struct btrfs_path *path;
1752 u64 last = 0;
1753 u64 start;
1754 u64 end;
1755 u64 ptr;
1756
1757 block_group_cache = &root->fs_info->block_group_cache;
1758 path = btrfs_alloc_path();
1759 if (!path)
1760 return -ENOMEM;
1761
1762 while(1) {
1763 ret = find_first_extent_bit(block_group_cache, last,
1764 &start, &end, BLOCK_GROUP_DIRTY);
1765 if (ret) {
1766 if (last == 0)
1767 break;
1768 last = 0;
1769 continue;
1770 }
1771
1772 last = end + 1;
1773 ret = get_state_private(block_group_cache, start, &ptr);
1774 BUG_ON(ret);
1775
1776 clear_extent_bits(block_group_cache, start, end,
1777 BLOCK_GROUP_DIRTY, GFP_NOFS);
1778
1779 cache = (struct btrfs_block_group_cache *)(unsigned long)ptr;
1780 ret = write_one_cache_group(trans, root, path, cache);
1781 }
1782 btrfs_free_path(path);
1783 return 0;
1784 }
1785
1786 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
1787 u64 flags)
1788 {
1789 struct btrfs_space_info *found;
1790
1791 flags &= BTRFS_BLOCK_GROUP_TYPE_MASK;
1792
1793 list_for_each_entry(found, &info->space_info, list) {
1794 if (found->flags & flags)
1795 return found;
1796 }
1797 return NULL;
1798
1799 }
1800
1801 static int free_space_info(struct btrfs_fs_info *fs_info, u64 flags,
1802 u64 total_bytes, u64 bytes_used,
1803 struct btrfs_space_info **space_info)
1804 {
1805 struct btrfs_space_info *found;
1806
1807 /* only support free block group which is empty */
1808 if (bytes_used)
1809 return -ENOTEMPTY;
1810
1811 found = __find_space_info(fs_info, flags);
1812 if (!found)
1813 return -ENOENT;
1814 if (found->total_bytes < total_bytes) {
1815 fprintf(stderr,
1816 "WARNING: bad space info to free %llu only have %llu\n",
1817 total_bytes, found->total_bytes);
1818 return -EINVAL;
1819 }
1820 found->total_bytes -= total_bytes;
1821 if (space_info)
1822 *space_info = found;
1823 return 0;
1824 }
1825
1826 static int update_space_info(struct btrfs_fs_info *info, u64 flags,
1827 u64 total_bytes, u64 bytes_used,
1828 struct btrfs_space_info **space_info)
1829 {
1830 struct btrfs_space_info *found;
1831
1832 found = __find_space_info(info, flags);
1833 if (found) {
1834 found->total_bytes += total_bytes;
1835 found->bytes_used += bytes_used;
1836 if (found->total_bytes < found->bytes_used) {
1837 fprintf(stderr, "warning, bad space info total_bytes "
1838 "%llu used %llu\n",
1839 (unsigned long long)found->total_bytes,
1840 (unsigned long long)found->bytes_used);
1841 }
1842 *space_info = found;
1843 return 0;
1844 }
1845 found = kmalloc(sizeof(*found), GFP_NOFS);
1846 if (!found)
1847 return -ENOMEM;
1848
1849 list_add(&found->list, &info->space_info);
1850 found->flags = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
1851 found->total_bytes = total_bytes;
1852 found->bytes_used = bytes_used;
1853 found->bytes_pinned = 0;
1854 found->full = 0;
1855 *space_info = found;
1856 return 0;
1857 }
1858
1859
1860 static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
1861 {
1862 u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 |
1863 BTRFS_BLOCK_GROUP_RAID1 |
1864 BTRFS_BLOCK_GROUP_RAID10 |
1865 BTRFS_BLOCK_GROUP_RAID5 |
1866 BTRFS_BLOCK_GROUP_RAID6 |
1867 BTRFS_BLOCK_GROUP_DUP);
1868 if (extra_flags) {
1869 if (flags & BTRFS_BLOCK_GROUP_DATA)
1870 fs_info->avail_data_alloc_bits |= extra_flags;
1871 if (flags & BTRFS_BLOCK_GROUP_METADATA)
1872 fs_info->avail_metadata_alloc_bits |= extra_flags;
1873 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
1874 fs_info->avail_system_alloc_bits |= extra_flags;
1875 }
1876 }
1877
1878 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
1879 struct btrfs_root *extent_root, u64 alloc_bytes,
1880 u64 flags)
1881 {
1882 struct btrfs_space_info *space_info;
1883 u64 thresh;
1884 u64 start;
1885 u64 num_bytes;
1886 int ret;
1887
1888 space_info = __find_space_info(extent_root->fs_info, flags);
1889 if (!space_info) {
1890 ret = update_space_info(extent_root->fs_info, flags,
1891 0, 0, &space_info);
1892 BUG_ON(ret);
1893 }
1894 BUG_ON(!space_info);
1895
1896 if (space_info->full)
1897 return 0;
1898
1899 thresh = div_factor(space_info->total_bytes, 7);
1900 if ((space_info->bytes_used + space_info->bytes_pinned + alloc_bytes) <
1901 thresh)
1902 return 0;
1903
1904 /*
1905 * Avoid allocating given chunk type
1906 */
1907 if (extent_root->fs_info->avoid_meta_chunk_alloc &&
1908 (flags & BTRFS_BLOCK_GROUP_METADATA))
1909 return 0;
1910 if (extent_root->fs_info->avoid_sys_chunk_alloc &&
1911 (flags & BTRFS_BLOCK_GROUP_SYSTEM))
1912 return 0;
1913
1914 ret = btrfs_alloc_chunk(trans, extent_root, &start, &num_bytes,
1915 space_info->flags);
1916 if (ret == -ENOSPC) {
1917 space_info->full = 1;
1918 return 0;
1919 }
1920
1921 BUG_ON(ret);
1922
1923 ret = btrfs_make_block_group(trans, extent_root, 0, space_info->flags,
1924 BTRFS_FIRST_CHUNK_TREE_OBJECTID, start, num_bytes);
1925 BUG_ON(ret);
1926 return 0;
1927 }
1928
1929 static int update_block_group(struct btrfs_trans_handle *trans,
1930 struct btrfs_root *root,
1931 u64 bytenr, u64 num_bytes, int alloc,
1932 int mark_free)
1933 {
1934 struct btrfs_block_group_cache *cache;
1935 struct btrfs_fs_info *info = root->fs_info;
1936 u64 total = num_bytes;
1937 u64 old_val;
1938 u64 byte_in_group;
1939 u64 start;
1940 u64 end;
1941
1942 /* block accounting for super block */
1943 old_val = btrfs_super_bytes_used(info->super_copy);
1944 if (alloc)
1945 old_val += num_bytes;
1946 else
1947 old_val -= num_bytes;
1948 btrfs_set_super_bytes_used(info->super_copy, old_val);
1949
1950 /* block accounting for root item */
1951 old_val = btrfs_root_used(&root->root_item);
1952 if (alloc)
1953 old_val += num_bytes;
1954 else
1955 old_val -= num_bytes;
1956 btrfs_set_root_used(&root->root_item, old_val);
1957
1958 while(total) {
1959 cache = btrfs_lookup_block_group(info, bytenr);
1960 if (!cache) {
1961 return -1;
1962 }
1963 byte_in_group = bytenr - cache->key.objectid;
1964 WARN_ON(byte_in_group > cache->key.offset);
1965 start = cache->key.objectid;
1966 end = start + cache->key.offset - 1;
1967 set_extent_bits(&info->block_group_cache, start, end,
1968 BLOCK_GROUP_DIRTY, GFP_NOFS);
1969
1970 old_val = btrfs_block_group_used(&cache->item);
1971 num_bytes = min(total, cache->key.offset - byte_in_group);
1972
1973 if (alloc) {
1974 old_val += num_bytes;
1975 cache->space_info->bytes_used += num_bytes;
1976 } else {
1977 old_val -= num_bytes;
1978 cache->space_info->bytes_used -= num_bytes;
1979 if (mark_free) {
1980 set_extent_dirty(&info->free_space_cache,
1981 bytenr, bytenr + num_bytes - 1,
1982 GFP_NOFS);
1983 }
1984 }
1985 btrfs_set_block_group_used(&cache->item, old_val);
1986 total -= num_bytes;
1987 bytenr += num_bytes;
1988 }
1989 return 0;
1990 }
1991
1992 static int update_pinned_extents(struct btrfs_root *root,
1993 u64 bytenr, u64 num, int pin)
1994 {
1995 u64 len;
1996 struct btrfs_block_group_cache *cache;
1997 struct btrfs_fs_info *fs_info = root->fs_info;
1998
1999 if (pin) {
2000 set_extent_dirty(&fs_info->pinned_extents,
2001 bytenr, bytenr + num - 1, GFP_NOFS);
2002 } else {
2003 clear_extent_dirty(&fs_info->pinned_extents,
2004 bytenr, bytenr + num - 1, GFP_NOFS);
2005 }
2006 while (num > 0) {
2007 cache = btrfs_lookup_block_group(fs_info, bytenr);
2008 if (!cache) {
2009 len = min((u64)root->sectorsize, num);
2010 goto next;
2011 }
2012 WARN_ON(!cache);
2013 len = min(num, cache->key.offset -
2014 (bytenr - cache->key.objectid));
2015 if (pin) {
2016 cache->pinned += len;
2017 cache->space_info->bytes_pinned += len;
2018 fs_info->total_pinned += len;
2019 } else {
2020 cache->pinned -= len;
2021 cache->space_info->bytes_pinned -= len;
2022 fs_info->total_pinned -= len;
2023 }
2024 next:
2025 bytenr += len;
2026 num -= len;
2027 }
2028 return 0;
2029 }
2030
2031 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
2032 struct btrfs_root *root,
2033 struct extent_io_tree *unpin)
2034 {
2035 u64 start;
2036 u64 end;
2037 int ret;
2038 struct extent_io_tree *free_space_cache;
2039 free_space_cache = &root->fs_info->free_space_cache;
2040
2041 while(1) {
2042 ret = find_first_extent_bit(unpin, 0, &start, &end,
2043 EXTENT_DIRTY);
2044 if (ret)
2045 break;
2046 update_pinned_extents(root, start, end + 1 - start, 0);
2047 clear_extent_dirty(unpin, start, end, GFP_NOFS);
2048 set_extent_dirty(free_space_cache, start, end, GFP_NOFS);
2049 }
2050 return 0;
2051 }
2052
2053 static int extent_root_pending_ops(struct btrfs_fs_info *info)
2054 {
2055 u64 start;
2056 u64 end;
2057 int ret;
2058
2059 ret = find_first_extent_bit(&info->extent_ins, 0, &start,
2060 &end, EXTENT_LOCKED);
2061 if (!ret) {
2062 ret = find_first_extent_bit(&info->pending_del, 0, &start, &end,
2063 EXTENT_LOCKED);
2064 }
2065 return ret == 0;
2066
2067 }
2068 static int finish_current_insert(struct btrfs_trans_handle *trans,
2069 struct btrfs_root *extent_root)
2070 {
2071 u64 start;
2072 u64 end;
2073 u64 priv;
2074 struct btrfs_fs_info *info = extent_root->fs_info;
2075 struct pending_extent_op *extent_op;
2076 struct btrfs_key key;
2077 int ret;
2078 int skinny_metadata =
2079 btrfs_fs_incompat(extent_root->fs_info, SKINNY_METADATA);
2080
2081 while(1) {
2082 ret = find_first_extent_bit(&info->extent_ins, 0, &start,
2083 &end, EXTENT_LOCKED);
2084 if (ret)
2085 break;
2086
2087 ret = get_state_private(&info->extent_ins, start, &priv);
2088 BUG_ON(ret);
2089 extent_op = (struct pending_extent_op *)(unsigned long)priv;
2090
2091 if (extent_op->type == PENDING_EXTENT_INSERT) {
2092 key.objectid = start;
2093 if (skinny_metadata) {
2094 key.offset = extent_op->level;
2095 key.type = BTRFS_METADATA_ITEM_KEY;
2096 } else {
2097 key.offset = extent_op->num_bytes;
2098 key.type = BTRFS_EXTENT_ITEM_KEY;
2099 }
2100 ret = alloc_reserved_tree_block(trans, extent_root,
2101 extent_root->root_key.objectid,
2102 trans->transid,
2103 extent_op->flags,
2104 &extent_op->key,
2105 extent_op->level, &key);
2106 BUG_ON(ret);
2107 } else {
2108 BUG_ON(1);
2109 }
2110
2111 clear_extent_bits(&info->extent_ins, start, end, EXTENT_LOCKED,
2112 GFP_NOFS);
2113 kfree(extent_op);
2114 }
2115 return 0;
2116 }
2117
2118 static int pin_down_bytes(struct btrfs_trans_handle *trans,
2119 struct btrfs_root *root,
2120 u64 bytenr, u64 num_bytes, int is_data)
2121 {
2122 int err = 0;
2123 struct extent_buffer *buf;
2124
2125 if (is_data)
2126 goto pinit;
2127
2128 buf = btrfs_find_tree_block(root, bytenr, num_bytes);
2129 if (!buf)
2130 goto pinit;
2131
2132 /* we can reuse a block if it hasn't been written
2133 * and it is from this transaction. We can't
2134 * reuse anything from the tree log root because
2135 * it has tiny sub-transactions.
2136 */
2137 if (btrfs_buffer_uptodate(buf, 0)) {
2138 u64 header_owner = btrfs_header_owner(buf);
2139 u64 header_transid = btrfs_header_generation(buf);
2140 if (header_owner != BTRFS_TREE_LOG_OBJECTID &&
2141 header_transid == trans->transid &&
2142 !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
2143 clean_tree_block(NULL, root, buf);
2144 free_extent_buffer(buf);
2145 return 1;
2146 }
2147 }
2148 free_extent_buffer(buf);
2149 pinit:
2150 update_pinned_extents(root, bytenr, num_bytes, 1);
2151
2152 BUG_ON(err < 0);
2153 return 0;
2154 }
2155
2156 void btrfs_pin_extent(struct btrfs_fs_info *fs_info,
2157 u64 bytenr, u64 num_bytes)
2158 {
2159 update_pinned_extents(fs_info->extent_root, bytenr, num_bytes, 1);
2160 }
2161
2162 void btrfs_unpin_extent(struct btrfs_fs_info *fs_info,
2163 u64 bytenr, u64 num_bytes)
2164 {
2165 update_pinned_extents(fs_info->extent_root, bytenr, num_bytes, 0);
2166 }
2167
2168 /*
2169 * remove an extent from the root, returns 0 on success
2170 */
2171 static int __free_extent(struct btrfs_trans_handle *trans,
2172 struct btrfs_root *root,
2173 u64 bytenr, u64 num_bytes, u64 parent,
2174 u64 root_objectid, u64 owner_objectid,
2175 u64 owner_offset, int refs_to_drop)
2176 {
2177
2178 struct btrfs_key key;
2179 struct btrfs_path *path;
2180 struct btrfs_root *extent_root = root->fs_info->extent_root;
2181 struct extent_buffer *leaf;
2182 struct btrfs_extent_item *ei;
2183 struct btrfs_extent_inline_ref *iref;
2184 int ret;
2185 int is_data;
2186 int extent_slot = 0;
2187 int found_extent = 0;
2188 int num_to_del = 1;
2189 u32 item_size;
2190 u64 refs;
2191 int skinny_metadata =
2192 btrfs_fs_incompat(extent_root->fs_info, SKINNY_METADATA);
2193
2194 if (root->fs_info->free_extent_hook) {
2195 root->fs_info->free_extent_hook(trans, root, bytenr, num_bytes,
2196 parent, root_objectid, owner_objectid,
2197 owner_offset, refs_to_drop);
2198
2199 }
2200 path = btrfs_alloc_path();
2201 if (!path)
2202 return -ENOMEM;
2203
2204 path->reada = 1;
2205
2206 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
2207 if (is_data)
2208 skinny_metadata = 0;
2209 BUG_ON(!is_data && refs_to_drop != 1);
2210
2211 ret = lookup_extent_backref(trans, extent_root, path, &iref,
2212 bytenr, num_bytes, parent,
2213 root_objectid, owner_objectid,
2214 owner_offset);
2215 if (ret == 0) {
2216 extent_slot = path->slots[0];
2217 while (extent_slot >= 0) {
2218 btrfs_item_key_to_cpu(path->nodes[0], &key,
2219 extent_slot);
2220 if (key.objectid != bytenr)
2221 break;
2222 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
2223 key.offset == num_bytes) {
2224 found_extent = 1;
2225 break;
2226 }
2227 if (key.type == BTRFS_METADATA_ITEM_KEY &&
2228 key.offset == owner_objectid) {
2229 found_extent = 1;
2230 break;
2231 }
2232 if (path->slots[0] - extent_slot > 5)
2233 break;
2234 extent_slot--;
2235 }
2236 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2237 item_size = btrfs_item_size_nr(path->nodes[0], extent_slot);
2238 if (found_extent && item_size < sizeof(*ei))
2239 found_extent = 0;
2240 #endif
2241 if (!found_extent) {
2242 BUG_ON(iref);
2243 ret = remove_extent_backref(trans, extent_root, path,
2244 NULL, refs_to_drop,
2245 is_data);
2246 BUG_ON(ret);
2247 btrfs_release_path(path);
2248
2249 key.objectid = bytenr;
2250
2251 if (skinny_metadata) {
2252 key.type = BTRFS_METADATA_ITEM_KEY;
2253 key.offset = owner_objectid;
2254 } else {
2255 key.type = BTRFS_EXTENT_ITEM_KEY;
2256 key.offset = num_bytes;
2257 }
2258
2259 ret = btrfs_search_slot(trans, extent_root,
2260 &key, path, -1, 1);
2261 if (ret > 0 && skinny_metadata && path->slots[0]) {
2262 path->slots[0]--;
2263 btrfs_item_key_to_cpu(path->nodes[0],
2264 &key,
2265 path->slots[0]);
2266 if (key.objectid == bytenr &&
2267 key.type == BTRFS_EXTENT_ITEM_KEY &&
2268 key.offset == num_bytes)
2269 ret = 0;
2270 }
2271
2272 if (ret > 0 && skinny_metadata) {
2273 skinny_metadata = 0;
2274 btrfs_release_path(path);
2275 key.type = BTRFS_EXTENT_ITEM_KEY;
2276 key.offset = num_bytes;
2277 ret = btrfs_search_slot(trans, extent_root,
2278 &key, path, -1, 1);
2279 }
2280
2281 if (ret) {
2282 printk(KERN_ERR "umm, got %d back from search"
2283 ", was looking for %llu\n", ret,
2284 (unsigned long long)bytenr);
2285 btrfs_print_leaf(extent_root, path->nodes[0]);
2286 }
2287 BUG_ON(ret);
2288 extent_slot = path->slots[0];
2289 }
2290 } else {
2291 printk(KERN_ERR "btrfs unable to find ref byte nr %llu "
2292 "parent %llu root %llu owner %llu offset %llu\n",
2293 (unsigned long long)bytenr,
2294 (unsigned long long)parent,
2295 (unsigned long long)root_objectid,
2296 (unsigned long long)owner_objectid,
2297 (unsigned long long)owner_offset);
2298 ret = -EIO;
2299 goto fail;
2300 }
2301
2302 leaf = path->nodes[0];
2303 item_size = btrfs_item_size_nr(leaf, extent_slot);
2304 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2305 if (item_size < sizeof(*ei)) {
2306 BUG_ON(found_extent || extent_slot != path->slots[0]);
2307 ret = convert_extent_item_v0(trans, extent_root, path,
2308 owner_objectid, 0);
2309 BUG_ON(ret < 0);
2310
2311 btrfs_release_path(path);
2312
2313 key.objectid = bytenr;
2314 key.type = BTRFS_EXTENT_ITEM_KEY;
2315 key.offset = num_bytes;
2316
2317 ret = btrfs_search_slot(trans, extent_root, &key, path,
2318 -1, 1);
2319 if (ret) {
2320 printk(KERN_ERR "umm, got %d back from search"
2321 ", was looking for %llu\n", ret,
2322 (unsigned long long)bytenr);
2323 btrfs_print_leaf(extent_root, path->nodes[0]);
2324 }
2325 BUG_ON(ret);
2326 extent_slot = path->slots[0];
2327 leaf = path->nodes[0];
2328 item_size = btrfs_item_size_nr(leaf, extent_slot);
2329 }
2330 #endif
2331 BUG_ON(item_size < sizeof(*ei));
2332 ei = btrfs_item_ptr(leaf, extent_slot,
2333 struct btrfs_extent_item);
2334 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID &&
2335 key.type == BTRFS_EXTENT_ITEM_KEY) {
2336 struct btrfs_tree_block_info *bi;
2337 BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
2338 bi = (struct btrfs_tree_block_info *)(ei + 1);
2339 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
2340 }
2341
2342 refs = btrfs_extent_refs(leaf, ei);
2343 BUG_ON(refs < refs_to_drop);
2344 refs -= refs_to_drop;
2345
2346 if (refs > 0) {
2347 /*
2348 * In the case of inline back ref, reference count will
2349 * be updated by remove_extent_backref
2350 */
2351 if (iref) {
2352 BUG_ON(!found_extent);
2353 } else {
2354 btrfs_set_extent_refs(leaf, ei, refs);
2355 btrfs_mark_buffer_dirty(leaf);
2356 }
2357 if (found_extent) {
2358 ret = remove_extent_backref(trans, extent_root, path,
2359 iref, refs_to_drop,
2360 is_data);
2361 BUG_ON(ret);
2362 }
2363 } else {
2364 int mark_free = 0;
2365 int pin = 1;
2366
2367 if (found_extent) {
2368 BUG_ON(is_data && refs_to_drop !=
2369 extent_data_ref_count(root, path, iref));
2370 if (iref) {
2371 BUG_ON(path->slots[0] != extent_slot);
2372 } else {
2373 BUG_ON(path->slots[0] != extent_slot + 1);
2374 path->slots[0] = extent_slot;
2375 num_to_del = 2;
2376 }
2377 }
2378
2379 if (pin) {
2380 ret = pin_down_bytes(trans, root, bytenr, num_bytes,
2381 is_data);
2382 if (ret > 0)
2383 mark_free = 1;
2384 BUG_ON(ret < 0);
2385 }
2386
2387 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
2388 num_to_del);
2389 BUG_ON(ret);
2390 btrfs_release_path(path);
2391
2392 if (is_data) {
2393 ret = btrfs_del_csums(trans, root, bytenr, num_bytes);
2394 BUG_ON(ret);
2395 }
2396
2397 update_block_group(trans, root, bytenr, num_bytes, 0, mark_free);
2398 }
2399 fail:
2400 btrfs_free_path(path);
2401 finish_current_insert(trans, extent_root);
2402 return ret;
2403 }
2404
2405 /*
2406 * find all the blocks marked as pending in the radix tree and remove
2407 * them from the extent map
2408 */
2409 static int del_pending_extents(struct btrfs_trans_handle *trans, struct
2410 btrfs_root *extent_root)
2411 {
2412 int ret;
2413 int err = 0;
2414 u64 start;
2415 u64 end;
2416 u64 priv;
2417 struct extent_io_tree *pending_del;
2418 struct extent_io_tree *extent_ins;
2419 struct pending_extent_op *extent_op;
2420
2421 extent_ins = &extent_root->fs_info->extent_ins;
2422 pending_del = &extent_root->fs_info->pending_del;
2423
2424 while(1) {
2425 ret = find_first_extent_bit(pending_del, 0, &start, &end,
2426 EXTENT_LOCKED);
2427 if (ret)
2428 break;
2429
2430 ret = get_state_private(pending_del, start, &priv);
2431 BUG_ON(ret);
2432 extent_op = (struct pending_extent_op *)(unsigned long)priv;
2433
2434 clear_extent_bits(pending_del, start, end, EXTENT_LOCKED,
2435 GFP_NOFS);
2436
2437 if (!test_range_bit(extent_ins, start, end,
2438 EXTENT_LOCKED, 0)) {
2439 ret = __free_extent(trans, extent_root,
2440 start, end + 1 - start, 0,
2441 extent_root->root_key.objectid,
2442 extent_op->level, 0, 1);
2443 kfree(extent_op);
2444 } else {
2445 kfree(extent_op);
2446 ret = get_state_private(extent_ins, start, &priv);
2447 BUG_ON(ret);
2448 extent_op = (struct pending_extent_op *)
2449 (unsigned long)priv;
2450
2451 clear_extent_bits(extent_ins, start, end,
2452 EXTENT_LOCKED, GFP_NOFS);
2453
2454 if (extent_op->type == PENDING_BACKREF_UPDATE)
2455 BUG_ON(1);
2456
2457 kfree(extent_op);
2458 }
2459 if (ret)
2460 err = ret;
2461 }
2462 return err;
2463 }
2464
2465
2466 int btrfs_free_tree_block(struct btrfs_trans_handle *trans,
2467 struct btrfs_root *root,
2468 struct extent_buffer *buf,
2469 u64 parent, int last_ref)
2470 {
2471 return btrfs_free_extent(trans, root, buf->start, buf->len, parent,
2472 root->root_key.objectid,
2473 btrfs_header_level(buf), 0);
2474 }
2475
2476 /*
2477 * remove an extent from the root, returns 0 on success
2478 */
2479
2480 int btrfs_free_extent(struct btrfs_trans_handle *trans,
2481 struct btrfs_root *root,
2482 u64 bytenr, u64 num_bytes, u64 parent,
2483 u64 root_objectid, u64 owner, u64 offset)
2484 {
2485 struct btrfs_root *extent_root = root->fs_info->extent_root;
2486 int pending_ret;
2487 int ret;
2488
2489 WARN_ON(num_bytes < root->sectorsize);
2490 if (root == extent_root) {
2491 struct pending_extent_op *extent_op;
2492
2493 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
2494 BUG_ON(!extent_op);
2495
2496 extent_op->type = PENDING_EXTENT_DELETE;
2497 extent_op->bytenr = bytenr;
2498 extent_op->num_bytes = num_bytes;
2499 extent_op->level = (int)owner;
2500
2501 set_extent_bits(&root->fs_info->pending_del,
2502 bytenr, bytenr + num_bytes - 1,
2503 EXTENT_LOCKED, GFP_NOFS);
2504 set_state_private(&root->fs_info->pending_del,
2505 bytenr, (unsigned long)extent_op);
2506 return 0;
2507 }
2508 ret = __free_extent(trans, root, bytenr, num_bytes, parent,
2509 root_objectid, owner, offset, 1);
2510 pending_ret = del_pending_extents(trans, root->fs_info->extent_root);
2511 return ret ? ret : pending_ret;
2512 }
2513
2514 static u64 stripe_align(struct btrfs_root *root, u64 val)
2515 {
2516 u64 mask = ((u64)root->stripesize - 1);
2517 u64 ret = (val + mask) & ~mask;
2518 return ret;
2519 }
2520
2521 /*
2522 * walks the btree of allocated extents and find a hole of a given size.
2523 * The key ins is changed to record the hole:
2524 * ins->objectid == block start
2525 * ins->flags = BTRFS_EXTENT_ITEM_KEY
2526 * ins->offset == number of blocks
2527 * Any available blocks before search_start are skipped.
2528 */
2529 static int noinline find_free_extent(struct btrfs_trans_handle *trans,
2530 struct btrfs_root *orig_root,
2531 u64 num_bytes, u64 empty_size,
2532 u64 search_start, u64 search_end,
2533 u64 hint_byte, struct btrfs_key *ins,
2534 u64 exclude_start, u64 exclude_nr,
2535 int data)
2536 {
2537 int ret;
2538 u64 orig_search_start = search_start;
2539 struct btrfs_root * root = orig_root->fs_info->extent_root;
2540 struct btrfs_fs_info *info = root->fs_info;
2541 u64 total_needed = num_bytes;
2542 struct btrfs_block_group_cache *block_group;
2543 int full_scan = 0;
2544 int wrapped = 0;
2545
2546 WARN_ON(num_bytes < root->sectorsize);
2547 ins->type = BTRFS_EXTENT_ITEM_KEY;
2548
2549 search_start = stripe_align(root, search_start);
2550
2551 if (hint_byte) {
2552 block_group = btrfs_lookup_first_block_group(info, hint_byte);
2553 if (!block_group)
2554 hint_byte = search_start;
2555 block_group = btrfs_find_block_group(root, block_group,
2556 hint_byte, data, 1);
2557 } else {
2558 block_group = btrfs_find_block_group(root,
2559 trans->block_group,
2560 search_start, data, 1);
2561 }
2562
2563 total_needed += empty_size;
2564
2565 check_failed:
2566 search_start = stripe_align(root, search_start);
2567 if (!block_group) {
2568 block_group = btrfs_lookup_first_block_group(info,
2569 search_start);
2570 if (!block_group)
2571 block_group = btrfs_lookup_first_block_group(info,
2572 orig_search_start);
2573 }
2574 ret = find_search_start(root, &block_group, &search_start,
2575 total_needed, data);
2576 if (ret)
2577 goto new_group;
2578
2579 ins->objectid = search_start;
2580 ins->offset = num_bytes;
2581
2582 if (ins->objectid + num_bytes >
2583 block_group->key.objectid + block_group->key.offset) {
2584 search_start = block_group->key.objectid +
2585 block_group->key.offset;
2586 goto new_group;
2587 }
2588
2589 if (test_range_bit(&info->extent_ins, ins->objectid,
2590 ins->objectid + num_bytes -1, EXTENT_LOCKED, 0)) {
2591 search_start = ins->objectid + num_bytes;
2592 goto new_group;
2593 }
2594
2595 if (test_range_bit(&info->pinned_extents, ins->objectid,
2596 ins->objectid + num_bytes -1, EXTENT_DIRTY, 0)) {
2597 search_start = ins->objectid + num_bytes;
2598 goto new_group;
2599 }
2600
2601 if (info->excluded_extents &&
2602 test_range_bit(info->excluded_extents, ins->objectid,
2603 ins->objectid + num_bytes -1, EXTENT_DIRTY, 0)) {
2604 search_start = ins->objectid + num_bytes;
2605 goto new_group;
2606 }
2607
2608 if (exclude_nr > 0 && (ins->objectid + num_bytes > exclude_start &&
2609 ins->objectid < exclude_start + exclude_nr)) {
2610 search_start = exclude_start + exclude_nr;
2611 goto new_group;
2612 }
2613
2614 if (!(data & BTRFS_BLOCK_GROUP_DATA)) {
2615 if (check_crossing_stripes(info, ins->objectid, num_bytes)) {
2616 struct btrfs_block_group_cache *bg_cache;
2617 u64 bg_offset;
2618
2619 bg_cache = btrfs_lookup_block_group(info, ins->objectid);
2620 if (!bg_cache)
2621 goto no_bg_cache;
2622 bg_offset = ins->objectid - bg_cache->key.objectid;
2623
2624 search_start = round_up(bg_offset + num_bytes,
2625 BTRFS_STRIPE_LEN) + bg_offset;
2626 goto new_group;
2627 }
2628 no_bg_cache:
2629 block_group = btrfs_lookup_block_group(info, ins->objectid);
2630 if (block_group)
2631 trans->block_group = block_group;
2632 }
2633 ins->offset = num_bytes;
2634 return 0;
2635
2636 new_group:
2637 block_group = btrfs_lookup_first_block_group(info, search_start);
2638 if (!block_group) {
2639 search_start = orig_search_start;
2640 if (full_scan) {
2641 ret = -ENOSPC;
2642 goto error;
2643 }
2644 if (wrapped) {
2645 if (!full_scan)
2646 total_needed -= empty_size;
2647 full_scan = 1;
2648 } else
2649 wrapped = 1;
2650 }
2651 cond_resched();
2652 block_group = btrfs_find_block_group(root, block_group,
2653 search_start, data, 0);
2654 goto check_failed;
2655
2656 error:
2657 return ret;
2658 }
2659
2660 int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
2661 struct btrfs_root *root,
2662 u64 num_bytes, u64 empty_size,
2663 u64 hint_byte, u64 search_end,
2664 struct btrfs_key *ins, int data)
2665 {
2666 int ret;
2667 u64 search_start = 0;
2668 u64 alloc_profile;
2669 struct btrfs_fs_info *info = root->fs_info;
2670
2671 if (data) {
2672 alloc_profile = info->avail_data_alloc_bits &
2673 info->data_alloc_profile;
2674 data = BTRFS_BLOCK_GROUP_DATA | alloc_profile;
2675 } else if ((info->system_allocs > 0 || root == info->chunk_root) &&
2676 info->system_allocs >= 0) {
2677 alloc_profile = info->avail_system_alloc_bits &
2678 info->system_alloc_profile;
2679 data = BTRFS_BLOCK_GROUP_SYSTEM | alloc_profile;
2680 } else {
2681 alloc_profile = info->avail_metadata_alloc_bits &
2682 info->metadata_alloc_profile;
2683 data = BTRFS_BLOCK_GROUP_METADATA | alloc_profile;
2684 }
2685
2686 if (root->ref_cows) {
2687 if (!(data & BTRFS_BLOCK_GROUP_METADATA)) {
2688 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
2689 num_bytes,
2690 BTRFS_BLOCK_GROUP_METADATA);
2691 BUG_ON(ret);
2692 }
2693 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
2694 num_bytes + 2 * 1024 * 1024, data);
2695 BUG_ON(ret);
2696 }
2697
2698 WARN_ON(num_bytes < root->sectorsize);
2699 ret = find_free_extent(trans, root, num_bytes, empty_size,
2700 search_start, search_end, hint_byte, ins,
2701 trans->alloc_exclude_start,
2702 trans->alloc_exclude_nr, data);
2703 BUG_ON(ret);
2704 clear_extent_dirty(&root->fs_info->free_space_cache,
2705 ins->objectid, ins->objectid + ins->offset - 1,
2706 GFP_NOFS);
2707 return ret;
2708 }
2709
2710 static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
2711 struct btrfs_root *root,
2712 u64 root_objectid, u64 generation,
2713 u64 flags, struct btrfs_disk_key *key,
2714 int level, struct btrfs_key *ins)
2715 {
2716 int ret;
2717 struct btrfs_fs_info *fs_info = root->fs_info;
2718 struct btrfs_extent_item *extent_item;
2719 struct btrfs_tree_block_info *block_info;
2720 struct btrfs_extent_inline_ref *iref;
2721 struct btrfs_path *path;
2722 struct extent_buffer *leaf;
2723 u32 size = sizeof(*extent_item) + sizeof(*iref);
2724 int skinny_metadata = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
2725
2726 if (!skinny_metadata)
2727 size += sizeof(*block_info);
2728
2729 path = btrfs_alloc_path();
2730 if (!path)
2731 return -ENOMEM;
2732
2733 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
2734 ins, size);
2735 BUG_ON(ret);
2736
2737 leaf = path->nodes[0];
2738 extent_item = btrfs_item_ptr(leaf, path->slots[0],
2739 struct btrfs_extent_item);
2740 btrfs_set_extent_refs(leaf, extent_item, 1);
2741 btrfs_set_extent_generation(leaf, extent_item, generation);
2742 btrfs_set_extent_flags(leaf, extent_item,
2743 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
2744
2745 if (skinny_metadata) {
2746 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
2747 } else {
2748 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
2749 btrfs_set_tree_block_key(leaf, block_info, key);
2750 btrfs_set_tree_block_level(leaf, block_info, level);
2751 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
2752 }
2753
2754 btrfs_set_extent_inline_ref_type(leaf, iref, BTRFS_TREE_BLOCK_REF_KEY);
2755 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
2756
2757 btrfs_mark_buffer_dirty(leaf);
2758 btrfs_free_path(path);
2759
2760 ret = update_block_group(trans, root, ins->objectid, root->nodesize,
2761 1, 0);
2762 return ret;
2763 }
2764
2765 static int alloc_tree_block(struct btrfs_trans_handle *trans,
2766 struct btrfs_root *root, u64 num_bytes,
2767 u64 root_objectid, u64 generation,
2768 u64 flags, struct btrfs_disk_key *key,
2769 int level, u64 empty_size, u64 hint_byte,
2770 u64 search_end, struct btrfs_key *ins)
2771 {
2772 int ret;
2773 ret = btrfs_reserve_extent(trans, root, num_bytes, empty_size,
2774 hint_byte, search_end, ins, 0);
2775 BUG_ON(ret);
2776
2777 if (root_objectid == BTRFS_EXTENT_TREE_OBJECTID) {
2778 struct pending_extent_op *extent_op;
2779
2780 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
2781 BUG_ON(!extent_op);
2782
2783 extent_op->type = PENDING_EXTENT_INSERT;
2784 extent_op->bytenr = ins->objectid;
2785 extent_op->num_bytes = ins->offset;
2786 extent_op->level = level;
2787 extent_op->flags = flags;
2788 memcpy(&extent_op->key, key, sizeof(*key));
2789
2790 set_extent_bits(&root->fs_info->extent_ins, ins->objectid,
2791 ins->objectid + ins->offset - 1,
2792 EXTENT_LOCKED, GFP_NOFS);
2793 set_state_private(&root->fs_info->extent_ins,
2794 ins->objectid, (unsigned long)extent_op);
2795 } else {
2796 if (btrfs_fs_incompat(root->fs_info, SKINNY_METADATA)) {
2797 ins->offset = level;
2798 ins->type = BTRFS_METADATA_ITEM_KEY;
2799 }
2800 ret = alloc_reserved_tree_block(trans, root, root_objectid,
2801 generation, flags,
2802 key, level, ins);
2803 finish_current_insert(trans, root->fs_info->extent_root);
2804 del_pending_extents(trans, root->fs_info->extent_root);
2805 }
2806 return ret;
2807 }
2808
2809 /*
2810 * helper function to allocate a block for a given tree
2811 * returns the tree buffer or NULL.
2812 */
2813 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
2814 struct btrfs_root *root,
2815 u32 blocksize, u64 root_objectid,
2816 struct btrfs_disk_key *key, int level,
2817 u64 hint, u64 empty_size)
2818 {
2819 struct btrfs_key ins;
2820 int ret;
2821 struct extent_buffer *buf;
2822
2823 ret = alloc_tree_block(trans, root, blocksize, root_objectid,
2824 trans->transid, 0, key, level,
2825 empty_size, hint, (u64)-1, &ins);
2826 if (ret) {
2827 BUG_ON(ret > 0);
2828 return ERR_PTR(ret);
2829 }
2830
2831 buf = btrfs_find_create_tree_block(root->fs_info, ins.objectid,
2832 blocksize);
2833 if (!buf) {
2834 btrfs_free_extent(trans, root, ins.objectid, ins.offset,
2835 0, root->root_key.objectid, level, 0);
2836 BUG_ON(1);
2837 return ERR_PTR(-ENOMEM);
2838 }
2839 btrfs_set_buffer_uptodate(buf);
2840 trans->blocks_used++;
2841
2842 return buf;
2843 }
2844
2845 #if 0
2846
2847 static int noinline drop_leaf_ref(struct btrfs_trans_handle *trans,
2848 struct btrfs_root *root,
2849 struct extent_buffer *leaf)
2850 {
2851 u64 leaf_owner;
2852 u64 leaf_generation;
2853 struct btrfs_key key;
2854 struct btrfs_file_extent_item *fi;
2855 int i;
2856 int nritems;
2857 int ret;
2858
2859 BUG_ON(!btrfs_is_leaf(leaf));
2860 nritems = btrfs_header_nritems(leaf);
2861 leaf_owner = btrfs_header_owner(leaf);
2862 leaf_generation = btrfs_header_generation(leaf);
2863
2864 for (i = 0; i < nritems; i++) {
2865 u64 disk_bytenr;
2866
2867 btrfs_item_key_to_cpu(leaf, &key, i);
2868 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2869 continue;
2870 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
2871 if (btrfs_file_extent_type(leaf, fi) ==
2872 BTRFS_FILE_EXTENT_INLINE)
2873 continue;
2874 /*
2875 * FIXME make sure to insert a trans record that
2876 * repeats the snapshot del on crash
2877 */
2878 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
2879 if (disk_bytenr == 0)
2880 continue;
2881 ret = btrfs_free_extent(trans, root, disk_bytenr,
2882 btrfs_file_extent_disk_num_bytes(leaf, fi),
2883 leaf->start, leaf_owner, leaf_generation,
2884 key.objectid, 0);
2885 BUG_ON(ret);
2886 }
2887 return 0;
2888 }
2889
2890 static void noinline reada_walk_down(struct btrfs_root *root,
2891 struct extent_buffer *node,
2892 int slot)
2893 {
2894 u64 bytenr;
2895 u64 last = 0;
2896 u32 nritems;
2897 u32 refs;
2898 u32 blocksize;
2899 int ret;
2900 int i;
2901 int level;
2902 int skipped = 0;
2903
2904 nritems = btrfs_header_nritems(node);
2905 level = btrfs_header_level(node);
2906 if (level)
2907 return;
2908
2909 for (i = slot; i < nritems && skipped < 32; i++) {
2910 bytenr = btrfs_node_blockptr(node, i);
2911 if (last && ((bytenr > last && bytenr - last > 32 * 1024) ||
2912 (last > bytenr && last - bytenr > 32 * 1024))) {
2913 skipped++;
2914 continue;
2915 }
2916 blocksize = btrfs_level_size(root, level - 1);
2917 if (i != slot) {
2918 ret = btrfs_lookup_extent_ref(NULL, root, bytenr,
2919 blocksize, &refs);
2920 BUG_ON(ret);
2921 if (refs != 1) {
2922 skipped++;
2923 continue;
2924 }
2925 }
2926 mutex_unlock(&root->fs_info->fs_mutex);
2927 ret = readahead_tree_block(root, bytenr, blocksize,
2928 btrfs_node_ptr_generation(node, i));
2929 last = bytenr + blocksize;
2930 cond_resched();
2931 mutex_lock(&root->fs_info->fs_mutex);
2932 if (ret)
2933 break;
2934 }
2935 }
2936
2937 /*
2938 * helper function for drop_snapshot, this walks down the tree dropping ref
2939 * counts as it goes.
2940 */
2941 static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
2942 struct btrfs_root *root,
2943 struct btrfs_path *path, int *level)
2944 {
2945 u64 root_owner;
2946 u64 root_gen;
2947 u64 bytenr;
2948 u64 ptr_gen;
2949 struct extent_buffer *next;
2950 struct extent_buffer *cur;
2951 struct extent_buffer *parent;
2952 u32 blocksize;
2953 int ret;
2954 u32 refs;
2955
2956 WARN_ON(*level < 0);
2957 WARN_ON(*level >= BTRFS_MAX_LEVEL);
2958 ret = btrfs_lookup_extent_ref(trans, root,
2959 path->nodes[*level]->start,
2960 path->nodes[*level]->len, &refs);
2961 BUG_ON(ret);
2962 if (refs > 1)
2963 goto out;
2964
2965 /*
2966 * walk down to the last node level and free all the leaves
2967 */
2968 while(*level >= 0) {
2969 WARN_ON(*level < 0);
2970 WARN_ON(*level >= BTRFS_MAX_LEVEL);
2971 cur = path->nodes[*level];
2972
2973 if (btrfs_header_level(cur) != *level)
2974 WARN_ON(1);
2975
2976 if (path->slots[*level] >=
2977 btrfs_header_nritems(cur))
2978 break;
2979 if (*level == 0) {
2980 ret = drop_leaf_ref(trans, root, cur);
2981 BUG_ON(ret);
2982 break;
2983 }
2984 bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
2985 ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
2986 blocksize = btrfs_level_size(root, *level - 1);
2987 ret = btrfs_lookup_extent_ref(trans, root, bytenr, blocksize,
2988 &refs);
2989 BUG_ON(ret);
2990 if (refs != 1) {
2991 parent = path->nodes[*level];
2992 root_owner = btrfs_header_owner(parent);
2993 root_gen = btrfs_header_generation(parent);
2994 path->slots[*level]++;
2995 ret = btrfs_free_extent(trans, root, bytenr, blocksize,
2996 parent->start, root_owner,
2997 root_gen, *level - 1, 1);
2998 BUG_ON(ret);
2999 continue;
3000 }
3001 next = btrfs_find_tree_block(root, bytenr, blocksize);
3002 if (!next || !btrfs_buffer_uptodate(next, ptr_gen)) {
3003 free_extent_buffer(next);
3004 reada_walk_down(root, cur, path->slots[*level]);
3005 mutex_unlock(&root->fs_info->fs_mutex);
3006 next = read_tree_block(root, bytenr, blocksize,
3007 ptr_gen);
3008 mutex_lock(&root->fs_info->fs_mutex);
3009 if (!extent_buffer_uptodate(next)) {
3010 if (IS_ERR(next))
3011 ret = PTR_ERR(next);
3012 else
3013 ret = -EIO;
3014 break;
3015 }
3016 }
3017 WARN_ON(*level <= 0);
3018 if (path->nodes[*level-1])
3019 free_extent_buffer(path->nodes[*level-1]);
3020 path->nodes[*level-1] = next;
3021 *level = btrfs_header_level(next);
3022 path->slots[*level] = 0;
3023 }
3024 out:
3025 WARN_ON(*level < 0);
3026 WARN_ON(*level >= BTRFS_MAX_LEVEL);
3027
3028 if (path->nodes[*level] == root->node) {
3029 root_owner = root->root_key.objectid;
3030 parent = path->nodes[*level];
3031 } else {
3032 parent = path->nodes[*level + 1];
3033 root_owner = btrfs_header_owner(parent);
3034 }
3035
3036 root_gen = btrfs_header_generation(parent);
3037 ret = btrfs_free_extent(trans, root, path->nodes[*level]->start,
3038 path->nodes[*level]->len, parent->start,
3039 root_owner, root_gen, *level, 1);
3040 free_extent_buffer(path->nodes[*level]);
3041 path->nodes[*level] = NULL;
3042 *level += 1;
3043 BUG_ON(ret);
3044 return 0;
3045 }
3046
3047 /*
3048 * helper for dropping snapshots. This walks back up the tree in the path
3049 * to find the first node higher up where we haven't yet gone through
3050 * all the slots
3051 */
3052 static int noinline walk_up_tree(struct btrfs_trans_handle *trans,
3053 struct btrfs_root *root,
3054 struct btrfs_path *path, int *level)
3055 {
3056 u64 root_owner;
3057 u64 root_gen;
3058 struct btrfs_root_item *root_item = &root->root_item;
3059 int i;
3060 int slot;
3061 int ret;
3062
3063 for(i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
3064 slot = path->slots[i];
3065 if (slot < btrfs_header_nritems(path->nodes[i]) - 1) {
3066 struct extent_buffer *node;
3067 struct btrfs_disk_key disk_key;
3068 node = path->nodes[i];
3069 path->slots[i]++;
3070 *level = i;
3071 WARN_ON(*level == 0);
3072 btrfs_node_key(node, &disk_key, path->slots[i]);
3073 memcpy(&root_item->drop_progress,
3074 &disk_key, sizeof(disk_key));
3075 root_item->drop_level = i;
3076 return 0;
3077 } else {
3078 struct extent_buffer *parent;
3079 if (path->nodes[*level] == root->node)
3080 parent = path->nodes[*level];
3081 else
3082 parent = path->nodes[*level + 1];
3083
3084 root_owner = btrfs_header_owner(parent);
3085 root_gen = btrfs_header_generation(parent);
3086 ret = btrfs_free_extent(trans, root,
3087 path->nodes[*level]->start,
3088 path->nodes[*level]->len,
3089 parent->start, root_owner,
3090 root_gen, *level, 1);
3091 BUG_ON(ret);
3092 free_extent_buffer(path->nodes[*level]);
3093 path->nodes[*level] = NULL;
3094 *level = i + 1;
3095 }
3096 }
3097 return 1;
3098 }
3099
3100 #endif
3101
3102 int btrfs_free_block_groups(struct btrfs_fs_info *info)
3103 {
3104 struct btrfs_space_info *sinfo;
3105 struct btrfs_block_group_cache *cache;
3106 u64 start;
3107 u64 end;
3108 u64 ptr;
3109 int ret;
3110
3111 while(1) {
3112 ret = find_first_extent_bit(&info->block_group_cache, 0,
3113 &start, &end, (unsigned int)-1);
3114 if (ret)
3115 break;
3116 ret = get_state_private(&info->block_group_cache, start, &ptr);
3117 if (!ret) {
3118 cache = u64_to_ptr(ptr);
3119 if (cache->free_space_ctl) {
3120 btrfs_remove_free_space_cache(cache);
3121 kfree(cache->free_space_ctl);
3122 }
3123 kfree(cache);
3124 }
3125 clear_extent_bits(&info->block_group_cache, start,
3126 end, (unsigned int)-1, GFP_NOFS);
3127 }
3128 while(1) {
3129 ret = find_first_extent_bit(&info->free_space_cache, 0,
3130 &start, &end, EXTENT_DIRTY);
3131 if (ret)
3132 break;
3133 clear_extent_dirty(&info->free_space_cache, start,
3134 end, GFP_NOFS);
3135 }
3136
3137 while (!list_empty(&info->space_info)) {
3138 sinfo = list_entry(info->space_info.next,
3139 struct btrfs_space_info, list);
3140 list_del_init(&sinfo->list);
3141 kfree(sinfo);
3142 }
3143 return 0;
3144 }
3145
3146 static int find_first_block_group(struct btrfs_root *root,
3147 struct btrfs_path *path, struct btrfs_key *key)
3148 {
3149 int ret;
3150 struct btrfs_key found_key;
3151 struct extent_buffer *leaf;
3152 int slot;
3153
3154 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
3155 if (ret < 0)
3156 return ret;
3157 while(1) {
3158 slot = path->slots[0];
3159 leaf = path->nodes[0];
3160 if (slot >= btrfs_header_nritems(leaf)) {
3161 ret = btrfs_next_leaf(root, path);
3162 if (ret == 0)
3163 continue;
3164 if (ret < 0)
3165 goto error;
3166 break;
3167 }
3168 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3169
3170 if (found_key.objectid >= key->objectid &&
3171 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY)
3172 return 0;
3173 path->slots[0]++;
3174 }
3175 ret = -ENOENT;
3176 error:
3177 return ret;
3178 }
3179
3180 static void account_super_bytes(struct btrfs_fs_info *fs_info,
3181 struct btrfs_block_group_cache *cache)
3182 {
3183 u64 bytenr;
3184 u64 *logical;
3185 int stripe_len;
3186 int i, nr, ret;
3187
3188 if (cache->key.objectid < BTRFS_SUPER_INFO_OFFSET) {
3189 stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->key.objectid;
3190 cache->bytes_super += stripe_len;
3191 }
3192
3193 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
3194 bytenr = btrfs_sb_offset(i);
3195 ret = btrfs_rmap_block(&fs_info->mapping_tree,
3196 cache->key.objectid, bytenr,
3197 0, &logical, &nr, &stripe_len);
3198 if (ret)
3199 return;
3200
3201 while (nr--) {
3202 u64 start, len;
3203
3204 if (logical[nr] > cache->key.objectid +
3205 cache->key.offset)
3206 continue;
3207
3208 if (logical[nr] + stripe_len <= cache->key.objectid)
3209 continue;
3210
3211 start = logical[nr];
3212 if (start < cache->key.objectid) {
3213 start = cache->key.objectid;
3214 len = (logical[nr] + stripe_len) - start;
3215 } else {
3216 len = min_t(u64, stripe_len,
3217 cache->key.objectid +
3218 cache->key.offset - start);
3219 }
3220
3221 cache->bytes_super += len;
3222 }
3223
3224 kfree(logical);
3225 }
3226 }
3227
3228 int btrfs_read_block_groups(struct btrfs_root *root)
3229 {
3230 struct btrfs_path *path;
3231 int ret;
3232 int bit;
3233 struct btrfs_block_group_cache *cache;
3234 struct btrfs_fs_info *info = root->fs_info;
3235 struct btrfs_space_info *space_info;
3236 struct extent_io_tree *block_group_cache;
3237 struct btrfs_key key;
3238 struct btrfs_key found_key;
3239 struct extent_buffer *leaf;
3240
3241 block_group_cache = &info->block_group_cache;
3242
3243 root = info->extent_root;
3244 key.objectid = 0;
3245 key.offset = 0;
3246 key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
3247 path = btrfs_alloc_path();
3248 if (!path)
3249 return -ENOMEM;
3250
3251 while(1) {
3252 ret = find_first_block_group(root, path, &key);
3253 if (ret > 0) {
3254 ret = 0;
3255 goto error;
3256 }
3257 if (ret != 0) {
3258 goto error;
3259 }
3260 leaf = path->nodes[0];
3261 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3262 cache = kzalloc(sizeof(*cache), GFP_NOFS);
3263 if (!cache) {
3264 ret = -ENOMEM;
3265 goto error;
3266 }
3267
3268 read_extent_buffer(leaf, &cache->item,
3269 btrfs_item_ptr_offset(leaf, path->slots[0]),
3270 sizeof(cache->item));
3271 memcpy(&cache->key, &found_key, sizeof(found_key));
3272 cache->cached = 0;
3273 cache->pinned = 0;
3274 key.objectid = found_key.objectid + found_key.offset;
3275 if (found_key.offset == 0)
3276 key.objectid++;
3277 btrfs_release_path(path);
3278 cache->flags = btrfs_block_group_flags(&cache->item);
3279 bit = 0;
3280 if (cache->flags & BTRFS_BLOCK_GROUP_DATA) {
3281 bit = BLOCK_GROUP_DATA;
3282 } else if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM) {
3283 bit = BLOCK_GROUP_SYSTEM;
3284 } else if (cache->flags & BTRFS_BLOCK_GROUP_METADATA) {
3285 bit = BLOCK_GROUP_METADATA;
3286 }
3287 set_avail_alloc_bits(info, cache->flags);
3288 if (btrfs_chunk_readonly(root, cache->key.objectid))
3289 cache->ro = 1;
3290
3291 account_super_bytes(info, cache);
3292
3293 ret = update_space_info(info, cache->flags, found_key.offset,
3294 btrfs_block_group_used(&cache->item),
3295 &space_info);
3296 BUG_ON(ret);
3297 cache->space_info = space_info;
3298
3299 /* use EXTENT_LOCKED to prevent merging */
3300 set_extent_bits(block_group_cache, found_key.objectid,
3301 found_key.objectid + found_key.offset - 1,
3302 bit | EXTENT_LOCKED, GFP_NOFS);
3303 set_state_private(block_group_cache, found_key.objectid,
3304 (unsigned long)cache);
3305 }
3306 ret = 0;
3307 error:
3308 btrfs_free_path(path);
3309 return ret;
3310 }
3311
3312 struct btrfs_block_group_cache *
3313 btrfs_add_block_group(struct btrfs_fs_info *fs_info, u64 bytes_used, u64 type,
3314 u64 chunk_objectid, u64 chunk_offset, u64 size)
3315 {
3316 int ret;
3317 int bit = 0;
3318 struct btrfs_block_group_cache *cache;
3319 struct extent_io_tree *block_group_cache;
3320
3321 block_group_cache = &fs_info->block_group_cache;
3322
3323 cache = kzalloc(sizeof(*cache), GFP_NOFS);
3324 BUG_ON(!cache);
3325 cache->key.objectid = chunk_offset;
3326 cache->key.offset = size;
3327
3328 cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
3329 btrfs_set_block_group_used(&cache->item, bytes_used);
3330 btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
3331 cache->flags = type;
3332 btrfs_set_block_group_flags(&cache->item, type);
3333
3334 account_super_bytes(fs_info, cache);
3335 ret = update_space_info(fs_info, cache->flags, size, bytes_used,
3336 &cache->space_info);
3337 BUG_ON(ret);
3338
3339 bit = block_group_state_bits(type);
3340 ret = set_extent_bits(block_group_cache, chunk_offset,
3341 chunk_offset + size - 1,
3342 bit | EXTENT_LOCKED, GFP_NOFS);
3343 BUG_ON(ret);
3344
3345 ret = set_state_private(block_group_cache, chunk_offset,
3346 (unsigned long)cache);
3347 BUG_ON(ret);
3348 set_avail_alloc_bits(fs_info, type);
3349
3350 return cache;
3351 }
3352
3353 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
3354 struct btrfs_root *root, u64 bytes_used,
3355 u64 type, u64 chunk_objectid, u64 chunk_offset,
3356 u64 size)
3357 {
3358 int ret;
3359 struct btrfs_root *extent_root;
3360 struct btrfs_block_group_cache *cache;
3361
3362 cache = btrfs_add_block_group(root->fs_info, bytes_used, type,
3363 chunk_objectid, chunk_offset, size);
3364 extent_root = root->fs_info->extent_root;
3365 ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
3366 sizeof(cache->item));
3367 BUG_ON(ret);
3368
3369 ret = finish_current_insert(trans, extent_root);
3370 BUG_ON(ret);
3371 ret = del_pending_extents(trans, extent_root);
3372 BUG_ON(ret);
3373
3374 return 0;
3375 }
3376
3377 /*
3378 * This is for converter use only.
3379 *
3380 * In that case, we don't know where are free blocks located.
3381 * Therefore all block group cache entries must be setup properly
3382 * before doing any block allocation.
3383 */
3384 int btrfs_make_block_groups(struct btrfs_trans_handle *trans,
3385 struct btrfs_root *root)
3386 {
3387 u64 total_bytes;
3388 u64 cur_start;
3389 u64 group_type;
3390 u64 group_size;
3391 u64 group_align;
3392 u64 total_data = 0;
3393 u64 total_metadata = 0;
3394 u64 chunk_objectid;
3395 int ret;
3396 int bit;
3397 struct btrfs_root *extent_root;
3398 struct btrfs_block_group_cache *cache;
3399 struct extent_io_tree *block_group_cache;
3400
3401 extent_root = root->fs_info->extent_root;
3402 block_group_cache = &root->fs_info->block_group_cache;
3403 chunk_objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
3404 total_bytes = btrfs_super_total_bytes(root->fs_info->super_copy);
3405 group_align = 64 * root->sectorsize;
3406
3407 cur_start = 0;
3408 while (cur_start < total_bytes) {
3409 group_size = total_bytes / 12;
3410 group_size = min_t(u64, group_size, total_bytes - cur_start);
3411 if (cur_start == 0) {
3412 bit = BLOCK_GROUP_SYSTEM;
3413 group_type = BTRFS_BLOCK_GROUP_SYSTEM;
3414 group_size /= 4;
3415 group_size &= ~(group_align - 1);
3416 group_size = max_t(u64, group_size, 8 * 1024 * 1024);
3417 group_size = min_t(u64, group_size, 32 * 1024 * 1024);
3418 } else {
3419 group_size &= ~(group_align - 1);
3420 if (total_data >= total_metadata * 2) {
3421 group_type = BTRFS_BLOCK_GROUP_METADATA;
3422 group_size = min_t(u64, group_size,
3423 1ULL * 1024 * 1024 * 1024);
3424 total_metadata += group_size;
3425 } else {
3426 group_type = BTRFS_BLOCK_GROUP_DATA;
3427 group_size = min_t(u64, group_size,
3428 5ULL * 1024 * 1024 * 1024);
3429 total_data += group_size;
3430 }
3431 if ((total_bytes - cur_start) * 4 < group_size * 5)
3432 group_size = total_bytes - cur_start;
3433 }
3434
3435 cache = kzalloc(sizeof(*cache), GFP_NOFS);
3436 BUG_ON(!cache);
3437
3438 cache->key.objectid = cur_start;
3439 cache->key.offset = group_size;
3440 cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
3441
3442 btrfs_set_block_group_used(&cache->item, 0);
3443 btrfs_set_block_group_chunk_objectid(&cache->item,
3444 chunk_objectid);
3445 btrfs_set_block_group_flags(&cache->item, group_type);
3446
3447 cache->flags = group_type;
3448
3449 ret = update_space_info(root->fs_info, group_type, group_size,
3450 0, &cache->space_info);
3451 BUG_ON(ret);
3452 set_avail_alloc_bits(extent_root->fs_info, group_type);
3453
3454 set_extent_bits(block_group_cache, cur_start,
3455 cur_start + group_size - 1,
3456 bit | EXTENT_LOCKED, GFP_NOFS);
3457 set_state_private(block_group_cache, cur_start,
3458 (unsigned long)cache);
3459 cur_start += group_size;
3460 }
3461 /* then insert all the items */
3462 cur_start = 0;
3463 while(cur_start < total_bytes) {
3464 cache = btrfs_lookup_block_group(root->fs_info, cur_start);
3465 BUG_ON(!cache);
3466
3467 ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
3468 sizeof(cache->item));
3469 BUG_ON(ret);
3470
3471 finish_current_insert(trans, extent_root);
3472 ret = del_pending_extents(trans, extent_root);
3473 BUG_ON(ret);
3474
3475 cur_start = cache->key.objectid + cache->key.offset;
3476 }
3477 return 0;
3478 }
3479
3480 int btrfs_update_block_group(struct btrfs_trans_handle *trans,
3481 struct btrfs_root *root,
3482 u64 bytenr, u64 num_bytes, int alloc,
3483 int mark_free)
3484 {
3485 return update_block_group(trans, root, bytenr, num_bytes,
3486 alloc, mark_free);
3487 }
3488
3489 /*
3490 * Just remove a block group item in extent tree
3491 * Caller should ensure the block group is empty and all space is pinned.
3492 * Or new tree block/data may be allocated into it.
3493 */
3494 static int free_block_group_item(struct btrfs_trans_handle *trans,
3495 struct btrfs_fs_info *fs_info,
3496 u64 bytenr, u64 len)
3497 {
3498 struct btrfs_path *path;
3499 struct btrfs_key key;
3500 struct btrfs_root *root = fs_info->extent_root;
3501 int ret = 0;
3502
3503 key.objectid = bytenr;
3504 key.offset = len;
3505 key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
3506
3507 path = btrfs_alloc_path();
3508 if (!path)
3509 return -ENOMEM;
3510
3511 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
3512 if (ret > 0) {
3513 ret = -ENOENT;
3514 goto out;
3515 }
3516 if (ret < 0)
3517 goto out;
3518
3519 ret = btrfs_del_item(trans, root, path);
3520 out:
3521 btrfs_free_path(path);
3522 return ret;
3523 }
3524
3525 static int free_dev_extent_item(struct btrfs_trans_handle *trans,
3526 struct btrfs_fs_info *fs_info,
3527 u64 devid, u64 dev_offset)
3528 {
3529 struct btrfs_root *root = fs_info->dev_root;
3530 struct btrfs_path *path;
3531 struct btrfs_key key;
3532 int ret;
3533
3534 path = btrfs_alloc_path();
3535 if (!path)
3536 return -ENOMEM;
3537
3538 key.objectid = devid;
3539 key.type = BTRFS_DEV_EXTENT_KEY;
3540 key.offset = dev_offset;
3541
3542 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
3543 if (ret < 0)
3544 goto out;
3545 if (ret > 0) {
3546 ret = -ENOENT;
3547 goto out;
3548 }
3549
3550 ret = btrfs_del_item(trans, root, path);
3551 out:
3552 btrfs_free_path(path);
3553 return ret;
3554 }
3555
3556 static int free_chunk_dev_extent_items(struct btrfs_trans_handle *trans,
3557 struct btrfs_fs_info *fs_info,
3558 u64 chunk_offset)
3559 {
3560 struct btrfs_chunk *chunk = NULL;
3561 struct btrfs_root *root= fs_info->chunk_root;
3562 struct btrfs_path *path;
3563 struct btrfs_key key;
3564 u16 num_stripes;
3565 int i;
3566 int ret;
3567
3568 path = btrfs_alloc_path();
3569 if (!path)
3570 return -ENOMEM;
3571
3572 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
3573 key.type = BTRFS_CHUNK_ITEM_KEY;
3574 key.offset = chunk_offset;
3575
3576 ret = btrfs_search_slot(trans, root, &key, path, 0, 0);
3577 if (ret < 0)
3578 goto out;
3579 if (ret > 0) {
3580 ret = -ENOENT;
3581 goto out;
3582 }
3583 chunk = btrfs_item_ptr(path->nodes[0], path->slots[0],
3584 struct btrfs_chunk);
3585 num_stripes = btrfs_chunk_num_stripes(path->nodes[0], chunk);
3586 for (i = 0; i < num_stripes; i++) {
3587 ret = free_dev_extent_item(trans, fs_info,
3588 btrfs_stripe_devid_nr(path->nodes[0], chunk, i),
3589 btrfs_stripe_offset_nr(path->nodes[0], chunk, i));
3590 if (ret < 0)
3591 goto out;
3592 }
3593 out:
3594 btrfs_free_path(path);
3595 return ret;
3596 }
3597
3598 static int free_system_chunk_item(struct btrfs_super_block *super,
3599 struct btrfs_key *key)
3600 {
3601 struct btrfs_disk_key *disk_key;
3602 struct btrfs_key cpu_key;
3603 u32 array_size = btrfs_super_sys_array_size(super);
3604 char *ptr = (char *)super->sys_chunk_array;
3605 int cur = 0;
3606 int ret = -ENOENT;
3607
3608 while (cur < btrfs_super_sys_array_size(super)) {
3609 struct btrfs_chunk *chunk;
3610 u32 num_stripes;
3611 u32 chunk_len;
3612
3613 disk_key = (struct btrfs_disk_key *)(ptr + cur);
3614 btrfs_disk_key_to_cpu(&cpu_key, disk_key);
3615 if (cpu_key.type != BTRFS_CHUNK_ITEM_KEY) {
3616 /* just in case */
3617 ret = -EIO;
3618 goto out;
3619 }
3620
3621 chunk = (struct btrfs_chunk *)(ptr + cur + sizeof(*disk_key));
3622 num_stripes = btrfs_stack_chunk_num_stripes(chunk);
3623 chunk_len = btrfs_chunk_item_size(num_stripes) +
3624 sizeof(*disk_key);
3625
3626 if (key->objectid == cpu_key.objectid &&
3627 key->offset == cpu_key.offset &&
3628 key->type == cpu_key.type) {
3629 memmove(ptr + cur, ptr + cur + chunk_len,
3630 array_size - cur - chunk_len);
3631 array_size -= chunk_len;
3632 btrfs_set_super_sys_array_size(super, array_size);
3633 ret = 0;
3634 goto out;
3635 }
3636
3637 cur += chunk_len;
3638 }
3639 out:
3640 return ret;
3641 }
3642
3643 static int free_chunk_item(struct btrfs_trans_handle *trans,
3644 struct btrfs_fs_info *fs_info,
3645 u64 bytenr, u64 len)
3646 {
3647 struct btrfs_path *path;
3648 struct btrfs_key key;
3649 struct btrfs_root *root = fs_info->chunk_root;
3650 struct btrfs_chunk *chunk;
3651 u64 chunk_type;
3652 int ret;
3653
3654 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
3655 key.offset = bytenr;
3656 key.type = BTRFS_CHUNK_ITEM_KEY;
3657
3658 path = btrfs_alloc_path();
3659 if (!path)
3660 return -ENOMEM;
3661
3662 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
3663 if (ret > 0) {
3664 ret = -ENOENT;
3665 goto out;
3666 }
3667 if (ret < 0)
3668 goto out;
3669 chunk = btrfs_item_ptr(path->nodes[0], path->slots[0],
3670 struct btrfs_chunk);
3671 chunk_type = btrfs_chunk_type(path->nodes[0], chunk);
3672
3673 ret = btrfs_del_item(trans, root, path);
3674 if (ret < 0)
3675 goto out;
3676
3677 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
3678 ret = free_system_chunk_item(fs_info->super_copy, &key);
3679 out:
3680 btrfs_free_path(path);
3681 return ret;
3682 }
3683
3684 static u64 get_dev_extent_len(struct map_lookup *map)
3685 {
3686 int div;
3687
3688 switch (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
3689 case 0: /* Single */
3690 case BTRFS_BLOCK_GROUP_DUP:
3691 case BTRFS_BLOCK_GROUP_RAID1:
3692 div = 1;
3693 break;
3694 case BTRFS_BLOCK_GROUP_RAID5:
3695 div = (map->num_stripes - 1);
3696 break;
3697 case BTRFS_BLOCK_GROUP_RAID6:
3698 div = (map->num_stripes - 2);
3699 break;
3700 case BTRFS_BLOCK_GROUP_RAID10:
3701 div = (map->num_stripes / map->sub_stripes);
3702 break;
3703 default:
3704 /* normally, read chunk security hook should handled it */
3705 BUG_ON(1);
3706 }
3707 return map->ce.size / div;
3708 }
3709
3710 /* free block group/chunk related caches */
3711 static int free_block_group_cache(struct btrfs_trans_handle *trans,
3712 struct btrfs_fs_info *fs_info,
3713 u64 bytenr, u64 len)
3714 {
3715 struct btrfs_block_group_cache *cache;
3716 struct cache_extent *ce;
3717 struct map_lookup *map;
3718 int ret;
3719 int i;
3720 u64 flags;
3721
3722 /* Free block group cache first */
3723 cache = btrfs_lookup_block_group(fs_info, bytenr);
3724 if (!cache)
3725 return -ENOENT;
3726 flags = cache->flags;
3727 if (cache->free_space_ctl) {
3728 btrfs_remove_free_space_cache(cache);
3729 kfree(cache->free_space_ctl);
3730 }
3731 clear_extent_bits(&fs_info->block_group_cache, bytenr, bytenr + len,
3732 (unsigned int)-1, GFP_NOFS);
3733 ret = free_space_info(fs_info, flags, len, 0, NULL);
3734 if (ret < 0)
3735 goto out;
3736 kfree(cache);
3737
3738 /* Then free mapping info and dev usage info */
3739 ce = search_cache_extent(&fs_info->mapping_tree.cache_tree, bytenr);
3740 if (!ce || ce->start != bytenr) {
3741 ret = -ENOENT;
3742 goto out;
3743 }
3744 map = container_of(ce, struct map_lookup, ce);
3745 for (i = 0; i < map->num_stripes; i++) {
3746 struct btrfs_device *device;
3747
3748 device = map->stripes[i].dev;
3749 device->bytes_used -= get_dev_extent_len(map);
3750 ret = btrfs_update_device(trans, device);
3751 if (ret < 0)
3752 goto out;
3753 }
3754 remove_cache_extent(&fs_info->mapping_tree.cache_tree, ce);
3755 free(map);
3756 out:
3757 return ret;
3758 }
3759
3760 int btrfs_free_block_group(struct btrfs_trans_handle *trans,
3761 struct btrfs_fs_info *fs_info, u64 bytenr, u64 len)
3762 {
3763 struct btrfs_root *extent_root = fs_info->extent_root;
3764 struct btrfs_path *path;
3765 struct btrfs_block_group_item *bgi;
3766 struct btrfs_key key;
3767 int ret = 0;
3768
3769 path = btrfs_alloc_path();
3770 if (!path)
3771 return -ENOMEM;
3772
3773 key.objectid = bytenr;
3774 key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
3775 key.offset = len;
3776
3777 /* Double check the block group to ensure it's empty */
3778 ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0);
3779 if (ret > 0) {
3780 ret = -ENONET;
3781 goto out;
3782 }
3783 if (ret < 0)
3784 goto out;
3785
3786 bgi = btrfs_item_ptr(path->nodes[0], path->slots[0],
3787 struct btrfs_block_group_item);
3788 if (btrfs_disk_block_group_used(path->nodes[0], bgi)) {
3789 fprintf(stderr,
3790 "WARNING: block group [%llu,%llu) is not empty\n",
3791 bytenr, bytenr + len);
3792 ret = -EINVAL;
3793 goto out;
3794 }
3795 btrfs_release_path(path);
3796
3797 /*
3798 * Now pin all space in the block group, to prevent further transaction
3799 * allocate space from it.
3800 * Every operation needs a transaction must be in the range.
3801 */
3802 btrfs_pin_extent(fs_info, bytenr, len);
3803
3804 /* delete block group item and chunk item */
3805 ret = free_block_group_item(trans, fs_info, bytenr, len);
3806 if (ret < 0) {
3807 fprintf(stderr,
3808 "failed to free block group item for [%llu,%llu)\n",
3809 bytenr, bytenr + len);
3810 btrfs_unpin_extent(fs_info, bytenr, len);
3811 goto out;
3812 }
3813
3814 ret = free_chunk_dev_extent_items(trans, fs_info, bytenr);
3815 if (ret < 0) {
3816 fprintf(stderr,
3817 "failed to dev extents belongs to [%llu,%llu)\n",
3818 bytenr, bytenr + len);
3819 btrfs_unpin_extent(fs_info, bytenr, len);
3820 goto out;
3821 }
3822 ret = free_chunk_item(trans, fs_info, bytenr, len);
3823 if (ret < 0) {
3824 fprintf(stderr,
3825 "failed to free chunk for [%llu,%llu)\n",
3826 bytenr, bytenr + len);
3827 btrfs_unpin_extent(fs_info, bytenr, len);
3828 goto out;
3829 }
3830
3831 /* Now release the block_group_cache */
3832 ret = free_block_group_cache(trans, fs_info, bytenr, len);
3833 btrfs_unpin_extent(fs_info, bytenr, len);
3834
3835 out:
3836 btrfs_free_path(path);
3837 return ret;
3838 }
3839
3840 /*
3841 * Fixup block accounting. The initial block accounting created by
3842 * make_block_groups isn't accuracy in this case.
3843 */
3844 int btrfs_fix_block_accounting(struct btrfs_trans_handle *trans,
3845 struct btrfs_root *root)
3846 {
3847 int ret;
3848 int slot;
3849 u64 start = 0;
3850 u64 bytes_used = 0;
3851 struct btrfs_path path;
3852 struct btrfs_key key;
3853 struct extent_buffer *leaf;
3854 struct btrfs_block_group_cache *cache;
3855 struct btrfs_fs_info *fs_info = root->fs_info;
3856
3857 root = root->fs_info->extent_root;
3858
3859 while(extent_root_pending_ops(fs_info)) {
3860 ret = finish_current_insert(trans, root);
3861 if (ret)
3862 return ret;
3863 ret = del_pending_extents(trans, root);
3864 if (ret)
3865 return ret;
3866 }
3867
3868 while(1) {
3869 cache = btrfs_lookup_first_block_group(fs_info, start);
3870 if (!cache)
3871 break;
3872 start = cache->key.objectid + cache->key.offset;
3873 btrfs_set_block_group_used(&cache->item, 0);
3874 cache->space_info->bytes_used = 0;
3875 set_extent_bits(&root->fs_info->block_group_cache,
3876 cache->key.objectid,
3877 cache->key.objectid + cache->key.offset -1,
3878 BLOCK_GROUP_DIRTY, GFP_NOFS);
3879 }
3880
3881 btrfs_init_path(&path);
3882 key.offset = 0;
3883 key.objectid = 0;
3884 key.type = BTRFS_EXTENT_ITEM_KEY;
3885 ret = btrfs_search_slot(trans, root->fs_info->extent_root,
3886 &key, &path, 0, 0);
3887 if (ret < 0)
3888 return ret;
3889 while(1) {
3890 leaf = path.nodes[0];
3891 slot = path.slots[0];
3892 if (slot >= btrfs_header_nritems(leaf)) {
3893 ret = btrfs_next_leaf(root, &path);
3894 if (ret < 0)
3895 return ret;
3896 if (ret > 0)
3897 break;
3898 leaf = path.nodes[0];
3899 slot = path.slots[0];
3900 }
3901 btrfs_item_key_to_cpu(leaf, &key, slot);
3902 if (key.type == BTRFS_EXTENT_ITEM_KEY) {
3903 bytes_used += key.offset;
3904 ret = btrfs_update_block_group(trans, root,
3905 key.objectid, key.offset, 1, 0);
3906 BUG_ON(ret);
3907 } else if (key.type == BTRFS_METADATA_ITEM_KEY) {
3908 bytes_used += root->nodesize;
3909 ret = btrfs_update_block_group(trans, root,
3910 key.objectid, root->nodesize, 1, 0);
3911 BUG_ON(ret);
3912 }
3913 path.slots[0]++;
3914 }
3915 btrfs_set_super_bytes_used(root->fs_info->super_copy, bytes_used);
3916 btrfs_release_path(&path);
3917 return 0;
3918 }
3919
3920 static void __get_extent_size(struct btrfs_root *root, struct btrfs_path *path,
3921 u64 *start, u64 *len)
3922 {
3923 struct btrfs_key key;
3924
3925 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
3926 BUG_ON(!(key.type == BTRFS_EXTENT_ITEM_KEY ||
3927 key.type == BTRFS_METADATA_ITEM_KEY));
3928 *start = key.objectid;
3929 if (key.type == BTRFS_EXTENT_ITEM_KEY)
3930 *len = key.offset;
3931 else
3932 *len = root->nodesize;
3933 }
3934
3935 /*
3936 * Find first overlap extent for range [bytenr, bytenr + len)
3937 * Return 0 for found and point path to it.
3938 * Return >0 for not found.
3939 * Return <0 for err
3940 */
3941 int btrfs_search_overlap_extent(struct btrfs_root *root,
3942 struct btrfs_path *path, u64 bytenr, u64 len)
3943 {
3944 struct btrfs_key key;
3945 u64 cur_start;
3946 u64 cur_len;
3947 int ret;
3948
3949 key.objectid = bytenr;
3950 key.type = BTRFS_EXTENT_DATA_KEY;
3951 key.offset = (u64)-1;
3952
3953 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3954 if (ret < 0)
3955 return ret;
3956 BUG_ON(ret == 0);
3957
3958 ret = btrfs_previous_extent_item(root, path, 0);
3959 if (ret < 0)
3960 return ret;
3961 /* no previous, check next extent */
3962 if (ret > 0)
3963 goto next;
3964 __get_extent_size(root, path, &cur_start, &cur_len);
3965 /* Tail overlap */
3966 if (cur_start + cur_len > bytenr)
3967 return 1;
3968
3969 next:
3970 ret = btrfs_next_extent_item(root, path, bytenr + len);
3971 if (ret < 0)
3972 return ret;
3973 /* No next, prev already checked, no overlap */
3974 if (ret > 0)
3975 return 0;
3976 __get_extent_size(root, path, &cur_start, &cur_len);
3977 /* head overlap*/
3978 if (cur_start < bytenr + len)
3979 return 1;
3980 return 0;
3981 }
3982
3983 static int __btrfs_record_file_extent(struct btrfs_trans_handle *trans,
3984 struct btrfs_root *root, u64 objectid,
3985 struct btrfs_inode_item *inode,
3986 u64 file_pos, u64 disk_bytenr,
3987 u64 *ret_num_bytes)
3988 {
3989 int ret;
3990 struct btrfs_fs_info *info = root->fs_info;
3991 struct btrfs_root *extent_root = info->extent_root;
3992 struct extent_buffer *leaf;
3993 struct btrfs_file_extent_item *fi;
3994 struct btrfs_key ins_key;
3995 struct btrfs_path *path;
3996 struct btrfs_extent_item *ei;
3997 u64 nbytes;
3998 u64 extent_num_bytes;
3999 u64 extent_bytenr;
4000 u64 extent_offset;
4001 u64 num_bytes = *ret_num_bytes;
4002
4003 /*
4004 * All supported file system should not use its 0 extent.
4005 * As it's for hole
4006 *
4007 * And hole extent has no size limit, no need to loop.
4008 */
4009 if (disk_bytenr == 0) {
4010 ret = btrfs_insert_file_extent(trans, root, objectid,
4011 file_pos, disk_bytenr,
4012 num_bytes, num_bytes);
4013 return ret;
4014 }
4015 num_bytes = min_t(u64, num_bytes, BTRFS_MAX_EXTENT_SIZE);
4016
4017 path = btrfs_alloc_path();
4018 if (!path)
4019 return -ENOMEM;
4020
4021 /* First to check extent overlap */
4022 ret = btrfs_search_overlap_extent(extent_root, path, disk_bytenr,
4023 num_bytes);
4024 if (ret < 0)
4025 goto fail;
4026 if (ret > 0) {
4027 /* Found overlap */
4028 u64 cur_start;
4029 u64 cur_len;
4030
4031 __get_extent_size(extent_root, path, &cur_start, &cur_len);
4032 /*
4033 * For convert case, this extent should be a subset of
4034 * existing one.
4035 */
4036 BUG_ON(disk_bytenr < cur_start);
4037
4038 extent_bytenr = cur_start;
4039 extent_num_bytes = cur_len;
4040 extent_offset = disk_bytenr - extent_bytenr;
4041 } else {
4042 /* No overlap, create new extent */
4043 btrfs_release_path(path);
4044 ins_key.objectid = disk_bytenr;
4045 ins_key.offset = num_bytes;
4046 ins_key.type = BTRFS_EXTENT_ITEM_KEY;
4047
4048 ret = btrfs_insert_empty_item(trans, extent_root, path,
4049 &ins_key, sizeof(*ei));
4050 if (ret == 0) {
4051 leaf = path->nodes[0];
4052 ei = btrfs_item_ptr(leaf, path->slots[0],
4053 struct btrfs_extent_item);
4054
4055 btrfs_set_extent_refs(leaf, ei, 0);
4056 btrfs_set_extent_generation(leaf, ei, 0);
4057 btrfs_set_extent_flags(leaf, ei,
4058 BTRFS_EXTENT_FLAG_DATA);
4059 btrfs_mark_buffer_dirty(leaf);
4060
4061 ret = btrfs_update_block_group(trans, root, disk_bytenr,
4062 num_bytes, 1, 0);
4063 if (ret)
4064 goto fail;
4065 } else if (ret != -EEXIST) {
4066 goto fail;
4067 }
4068 btrfs_extent_post_op(trans, extent_root);
4069 extent_bytenr = disk_bytenr;
4070 extent_num_bytes = num_bytes;
4071 extent_offset = 0;
4072 }
4073 btrfs_release_path(path);
4074 ins_key.objectid = objectid;
4075 ins_key.offset = file_pos;
4076 ins_key.type = BTRFS_EXTENT_DATA_KEY;
4077 ret = btrfs_insert_empty_item(trans, root, path, &ins_key,
4078 sizeof(*fi));
4079 if (ret)
4080 goto fail;
4081 leaf = path->nodes[0];
4082 fi = btrfs_item_ptr(leaf, path->slots[0],
4083 struct btrfs_file_extent_item);
4084 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
4085 btrfs_set_file_extent_type(leaf, fi, BTRFS_FILE_EXTENT_REG);
4086 btrfs_set_file_extent_disk_bytenr(leaf, fi, extent_bytenr);
4087 btrfs_set_file_extent_disk_num_bytes(leaf, fi, extent_num_bytes);
4088 btrfs_set_file_extent_offset(leaf, fi, extent_offset);
4089 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
4090 btrfs_set_file_extent_ram_bytes(leaf, fi, extent_num_bytes);
4091 btrfs_set_file_extent_compression(leaf, fi, 0);
4092 btrfs_set_file_extent_encryption(leaf, fi, 0);
4093 btrfs_set_file_extent_other_encoding(leaf, fi, 0);
4094 btrfs_mark_buffer_dirty(leaf);
4095
4096 nbytes = btrfs_stack_inode_nbytes(inode) + num_bytes;
4097 btrfs_set_stack_inode_nbytes(inode, nbytes);
4098 btrfs_release_path(path);
4099
4100 ret = btrfs_inc_extent_ref(trans, root, extent_bytenr, extent_num_bytes,
4101 0, root->root_key.objectid, objectid,
4102 file_pos - extent_offset);
4103 if (ret)
4104 goto fail;
4105 ret = 0;
4106 *ret_num_bytes = min(extent_num_bytes - extent_offset, num_bytes);
4107 fail:
4108 btrfs_free_path(path);
4109 return ret;
4110 }
4111
4112 /*
4113 * Record a file extent. Do all the required works, such as inserting
4114 * file extent item, inserting extent item and backref item into extent
4115 * tree and updating block accounting.
4116 */
4117 int btrfs_record_file_extent(struct btrfs_trans_handle *trans,
4118 struct btrfs_root *root, u64 objectid,
4119 struct btrfs_inode_item *inode,
4120 u64 file_pos, u64 disk_bytenr,
4121 u64 num_bytes)
4122 {
4123 u64 cur_disk_bytenr = disk_bytenr;
4124 u64 cur_file_pos = file_pos;
4125 u64 cur_num_bytes = num_bytes;
4126 int ret = 0;
4127
4128 while (num_bytes > 0) {
4129 ret = __btrfs_record_file_extent(trans, root, objectid,
4130 inode, cur_file_pos,
4131 cur_disk_bytenr,
4132 &cur_num_bytes);
4133 if (ret < 0)
4134 break;
4135 cur_disk_bytenr += cur_num_bytes;
4136 cur_file_pos += cur_num_bytes;
4137 num_bytes -= cur_num_bytes;
4138 }
4139 return ret;
4140 }
4141
4142
4143 static int add_excluded_extent(struct btrfs_root *root,
4144 u64 start, u64 num_bytes)
4145 {
4146 u64 end = start + num_bytes - 1;
4147 set_extent_bits(&root->fs_info->pinned_extents,
4148 start, end, EXTENT_UPTODATE, GFP_NOFS);
4149 return 0;
4150 }
4151
4152 void free_excluded_extents(struct btrfs_root *root,
4153 struct btrfs_block_group_cache *cache)
4154 {
4155 u64 start, end;
4156
4157 start = cache->key.objectid;
4158 end = start + cache->key.offset - 1;
4159
4160 clear_extent_bits(&root->fs_info->pinned_extents,
4161 start, end, EXTENT_UPTODATE, GFP_NOFS);
4162 }
4163
4164 int exclude_super_stripes(struct btrfs_root *root,
4165 struct btrfs_block_group_cache *cache)
4166 {
4167 u64 bytenr;
4168 u64 *logical;
4169 int stripe_len;
4170 int i, nr, ret;
4171
4172 if (cache->key.objectid < BTRFS_SUPER_INFO_OFFSET) {
4173 stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->key.objectid;
4174 cache->bytes_super += stripe_len;
4175 ret = add_excluded_extent(root, cache->key.objectid,
4176 stripe_len);
4177 if (ret)
4178 return ret;
4179 }
4180
4181 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
4182 bytenr = btrfs_sb_offset(i);
4183 ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
4184 cache->key.objectid, bytenr,
4185 0, &logical, &nr, &stripe_len);
4186 if (ret)
4187 return ret;
4188
4189 while (nr--) {
4190 u64 start, len;
4191
4192 if (logical[nr] > cache->key.objectid +
4193 cache->key.offset)
4194 continue;
4195
4196 if (logical[nr] + stripe_len <= cache->key.objectid)
4197 continue;
4198
4199 start = logical[nr];
4200 if (start < cache->key.objectid) {
4201 start = cache->key.objectid;
4202 len = (logical[nr] + stripe_len) - start;
4203 } else {
4204 len = min_t(u64, stripe_len,
4205 cache->key.objectid +
4206 cache->key.offset - start);
4207 }
4208
4209 cache->bytes_super += len;
4210 ret = add_excluded_extent(root, start, len);
4211 if (ret) {
4212 kfree(logical);
4213 return ret;
4214 }
4215 }
4216
4217 kfree(logical);
4218 }
4219 return 0;
4220 }
4221
4222 u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
4223 struct btrfs_fs_info *info, u64 start, u64 end)
4224 {
4225 u64 extent_start, extent_end, size, total_added = 0;
4226 int ret;
4227
4228 while (start < end) {
4229 ret = find_first_extent_bit(&info->pinned_extents, start,
4230 &extent_start, &extent_end,
4231 EXTENT_DIRTY | EXTENT_UPTODATE);
4232 if (ret)
4233 break;
4234
4235 if (extent_start <= start) {
4236 start = extent_end + 1;
4237 } else if (extent_start > start && extent_start < end) {
4238 size = extent_start - start;
4239 total_added += size;
4240 ret = btrfs_add_free_space(block_group->free_space_ctl,
4241 start, size);
4242 BUG_ON(ret); /* -ENOMEM or logic error */
4243 start = extent_end + 1;
4244 } else {
4245 break;
4246 }
4247 }
4248
4249 if (start < end) {
4250 size = end - start;
4251 total_added += size;
4252 ret = btrfs_add_free_space(block_group->free_space_ctl, start,
4253 size);
4254 BUG_ON(ret); /* -ENOMEM or logic error */
4255 }
4256
4257 return total_added;
4258 }
(deprecated) Btrfs progs developments and patch integration