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Btrfs: fix locking issue in btrfs_find_next_key
[deliverable/linux.git] / fs / btrfs / extent-tree.c
CommitLineData
6cbd5570
CM		 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 */
ec6b910f 18#include <linux/sched.h>
edbd8d4e 19#include <linux/pagemap.h>
ec44a35c 20#include <linux/writeback.h>
21af804c 21#include <linux/blkdev.h>
b7a9f29f 22#include <linux/sort.h>
4184ea7f 23#include <linux/rcupdate.h>
4b4e25f2 24#include "compat.h"
74493f7a 25#include "hash.h"
fec577fb
CM		 26#include "ctree.h"
27#include "disk-io.h"
28#include "print-tree.h"
e089f05c 29#include "transaction.h"
0b86a832 30#include "volumes.h"
925baedd 31#include "locking.h"
fa9c0d79 32#include "free-space-cache.h"
fec577fb 33
56bec294
CM		 34static int update_reserved_extents(struct btrfs_root *root,
35 u64 bytenr, u64 num, int reserve);
f3465ca4
JB		 36static int update_block_group(struct btrfs_trans_handle *trans,
37 struct btrfs_root *root,
38 u64 bytenr, u64 num_bytes, int alloc,
39 int mark_free);
5d4f98a2
YZ		 40static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
41 struct btrfs_root *root,
42 u64 bytenr, u64 num_bytes, u64 parent,
43 u64 root_objectid, u64 owner_objectid,
44 u64 owner_offset, int refs_to_drop,
45 struct btrfs_delayed_extent_op *extra_op);
46static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
47 struct extent_buffer *leaf,
48 struct btrfs_extent_item *ei);
49static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
50 struct btrfs_root *root,
51 u64 parent, u64 root_objectid,
52 u64 flags, u64 owner, u64 offset,
53 struct btrfs_key *ins, int ref_mod);
54static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
55 struct btrfs_root *root,
56 u64 parent, u64 root_objectid,
57 u64 flags, struct btrfs_disk_key *key,
58 int level, struct btrfs_key *ins);
d548ee51 59
6a63209f
JB		 60static int do_chunk_alloc(struct btrfs_trans_handle *trans,
61 struct btrfs_root *extent_root, u64 alloc_bytes,
62 u64 flags, int force);
63
0f9dd46c
JB		 64static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
65{
66 return (cache->flags & bits) == bits;
67}
68
69/*
70 * this adds the block group to the fs_info rb tree for the block group
71 * cache
72 */
b2950863 73static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
0f9dd46c
JB		 74 struct btrfs_block_group_cache *block_group)
75{
76 struct rb_node **p;
77 struct rb_node *parent = NULL;
78 struct btrfs_block_group_cache *cache;
79
80 spin_lock(&info->block_group_cache_lock);
81 p = &info->block_group_cache_tree.rb_node;
82
83 while (*p) {
84 parent = *p;
85 cache = rb_entry(parent, struct btrfs_block_group_cache,
86 cache_node);
87 if (block_group->key.objectid < cache->key.objectid) {
88 p = &(*p)->rb_left;
89 } else if (block_group->key.objectid > cache->key.objectid) {
90 p = &(*p)->rb_right;
91 } else {
92 spin_unlock(&info->block_group_cache_lock);
93 return -EEXIST;
94 }
95 }
96
97 rb_link_node(&block_group->cache_node, parent, p);
98 rb_insert_color(&block_group->cache_node,
99 &info->block_group_cache_tree);
100 spin_unlock(&info->block_group_cache_lock);
101
102 return 0;
103}
104
105/*
106 * This will return the block group at or after bytenr if contains is 0, else
107 * it will return the block group that contains the bytenr
108 */
109static struct btrfs_block_group_cache *
110block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
111 int contains)
112{
113 struct btrfs_block_group_cache *cache, *ret = NULL;
114 struct rb_node *n;
115 u64 end, start;
116
117 spin_lock(&info->block_group_cache_lock);
118 n = info->block_group_cache_tree.rb_node;
119
120 while (n) {
121 cache = rb_entry(n, struct btrfs_block_group_cache,
122 cache_node);
123 end = cache->key.objectid + cache->key.offset - 1;
124 start = cache->key.objectid;
125
126 if (bytenr < start) {
127 if (!contains && (!ret || start < ret->key.objectid))
128 ret = cache;
129 n = n->rb_left;
130 } else if (bytenr > start) {
131 if (contains && bytenr <= end) {
132 ret = cache;
133 break;
134 }
135 n = n->rb_right;
136 } else {
137 ret = cache;
138 break;
139 }
140 }
d2fb3437
YZ		 141 if (ret)
142 atomic_inc(&ret->count);
0f9dd46c
JB		 143 spin_unlock(&info->block_group_cache_lock);
144
145 return ret;
146}
147
148/*
149 * this is only called by cache_block_group, since we could have freed extents
150 * we need to check the pinned_extents for any extents that can't be used yet
151 * since their free space will be released as soon as the transaction commits.
152 */
153static int add_new_free_space(struct btrfs_block_group_cache *block_group,
154 struct btrfs_fs_info *info, u64 start, u64 end)
155{
156 u64 extent_start, extent_end, size;
157 int ret;
158
159 while (start < end) {
160 ret = find_first_extent_bit(&info->pinned_extents, start,
161 &extent_start, &extent_end,
162 EXTENT_DIRTY);
163 if (ret)
164 break;
165
166 if (extent_start == start) {
167 start = extent_end + 1;
168 } else if (extent_start > start && extent_start < end) {
169 size = extent_start - start;
ea6a478e
JB		 170 ret = btrfs_add_free_space(block_group, start,
171 size);
0f9dd46c
JB		 172 BUG_ON(ret);
173 start = extent_end + 1;
174 } else {
175 break;
176 }
177 }
178
179 if (start < end) {
180 size = end - start;
ea6a478e 181 ret = btrfs_add_free_space(block_group, start, size);
0f9dd46c
JB		 182 BUG_ON(ret);
183 }
184
185 return 0;
186}
187
a512bbf8
YZ		 188static int remove_sb_from_cache(struct btrfs_root *root,
189 struct btrfs_block_group_cache *cache)
190{
191 u64 bytenr;
192 u64 *logical;
193 int stripe_len;
194 int i, nr, ret;
195
196 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
197 bytenr = btrfs_sb_offset(i);
198 ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
199 cache->key.objectid, bytenr, 0,
200 &logical, &nr, &stripe_len);
201 BUG_ON(ret);
202 while (nr--) {
203 btrfs_remove_free_space(cache, logical[nr],
204 stripe_len);
205 }
206 kfree(logical);
207 }
208 return 0;
209}
210
e37c9e69
CM		 211static int cache_block_group(struct btrfs_root *root,
212 struct btrfs_block_group_cache *block_group)
213{
214 struct btrfs_path *path;
ef8bbdfe 215 int ret = 0;
e37c9e69 216 struct btrfs_key key;
5f39d397 217 struct extent_buffer *leaf;
e37c9e69 218 int slot;
e4404d6e 219 u64 last;
e37c9e69 220
00f5c795
CM		 221 if (!block_group)
222 return 0;
223
e37c9e69 224 root = root->fs_info->extent_root;
e37c9e69
CM		 225
226 if (block_group->cached)
227 return 0;
f510cfec 228
e37c9e69
CM		 229 path = btrfs_alloc_path();
230 if (!path)
231 return -ENOMEM;
7d7d6068 232
2cc58cf2 233 path->reada = 2;
5cd57b2c
CM		 234 /*
235 * we get into deadlocks with paths held by callers of this function.
236 * since the alloc_mutex is protecting things right now, just
237 * skip the locking here
238 */
239 path->skip_locking = 1;
e4404d6e
YZ		 240 last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
241 key.objectid = last;
e37c9e69
CM		 242 key.offset = 0;
243 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
244 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
245 if (ret < 0)
ef8bbdfe 246 goto err;
a512bbf8 247
d397712b 248 while (1) {
5f39d397 249 leaf = path->nodes[0];
e37c9e69 250 slot = path->slots[0];
5f39d397 251 if (slot >= btrfs_header_nritems(leaf)) {
e37c9e69 252 ret = btrfs_next_leaf(root, path);
54aa1f4d
CM		 253 if (ret < 0)
254 goto err;
0f9dd46c 255 if (ret == 0)
e37c9e69 256 continue;
0f9dd46c 257 else
e37c9e69 258 break;
e37c9e69 259 }
5f39d397 260 btrfs_item_key_to_cpu(leaf, &key, slot);
0f9dd46c 261 if (key.objectid < block_group->key.objectid)
7d7d6068 262 goto next;
0f9dd46c 263
e37c9e69 264 if (key.objectid >= block_group->key.objectid +
0f9dd46c 265 block_group->key.offset)
e37c9e69 266 break;
7d7d6068 267
e37c9e69 268 if (btrfs_key_type(&key) == BTRFS_EXTENT_ITEM_KEY) {
0f9dd46c
JB		 269 add_new_free_space(block_group, root->fs_info, last,
270 key.objectid);
271
7d7d6068 272 last = key.objectid + key.offset;
e37c9e69 273 }
7d7d6068 274next:
e37c9e69
CM		 275 path->slots[0]++;
276 }
277
0f9dd46c
JB		 278 add_new_free_space(block_group, root->fs_info, last,
279 block_group->key.objectid +
280 block_group->key.offset);
281
e37c9e69 282 block_group->cached = 1;
70cb0743 283 remove_sb_from_cache(root, block_group);
ef8bbdfe 284 ret = 0;
54aa1f4d 285err:
e37c9e69 286 btrfs_free_path(path);
ef8bbdfe 287 return ret;
e37c9e69
CM		 288}
289
0f9dd46c
JB		 290/*
291 * return the block group that starts at or after bytenr
292 */
d397712b
CM		 293static struct btrfs_block_group_cache *
294btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr)
0ef3e66b 295{
0f9dd46c 296 struct btrfs_block_group_cache *cache;
0ef3e66b 297
0f9dd46c 298 cache = block_group_cache_tree_search(info, bytenr, 0);
0ef3e66b 299
0f9dd46c 300 return cache;
0ef3e66b
CM		 301}
302
0f9dd46c 303/*
9f55684c 304 * return the block group that contains the given bytenr
0f9dd46c 305 */
d397712b
CM		 306struct btrfs_block_group_cache *btrfs_lookup_block_group(
307 struct btrfs_fs_info *info,
308 u64 bytenr)
be744175 309{
0f9dd46c 310 struct btrfs_block_group_cache *cache;
be744175 311
0f9dd46c 312 cache = block_group_cache_tree_search(info, bytenr, 1);
96b5179d 313
0f9dd46c 314 return cache;
be744175 315}
0b86a832 316
fa9c0d79 317void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
d2fb3437
YZ		 318{
319 if (atomic_dec_and_test(&cache->count))
320 kfree(cache);
321}
322
0f9dd46c
JB		 323static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
324 u64 flags)
6324fbf3 325{
0f9dd46c 326 struct list_head *head = &info->space_info;
0f9dd46c 327 struct btrfs_space_info *found;
4184ea7f
CM		 328
329 rcu_read_lock();
330 list_for_each_entry_rcu(found, head, list) {
331 if (found->flags == flags) {
332 rcu_read_unlock();
0f9dd46c 333 return found;
4184ea7f 334 }
0f9dd46c 335 }
4184ea7f 336 rcu_read_unlock();
0f9dd46c 337 return NULL;
6324fbf3
CM		 338}
339
4184ea7f
CM		 340/*
341 * after adding space to the filesystem, we need to clear the full flags
342 * on all the space infos.
343 */
344void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
345{
346 struct list_head *head = &info->space_info;
347 struct btrfs_space_info *found;
348
349 rcu_read_lock();
350 list_for_each_entry_rcu(found, head, list)
351 found->full = 0;
352 rcu_read_unlock();
353}
354
80eb234a
JB		 355static u64 div_factor(u64 num, int factor)
356{
357 if (factor == 10)
358 return num;
359 num *= factor;
360 do_div(num, 10);
361 return num;
362}
363
d2fb3437
YZ		 364u64 btrfs_find_block_group(struct btrfs_root *root,
365 u64 search_start, u64 search_hint, int owner)
cd1bc465 366{
96b5179d 367 struct btrfs_block_group_cache *cache;
cd1bc465 368 u64 used;
d2fb3437
YZ		 369 u64 last = max(search_hint, search_start);
370 u64 group_start = 0;
31f3c99b 371 int full_search = 0;
d2fb3437 372 int factor = 9;
0ef3e66b 373 int wrapped = 0;
31f3c99b 374again:
e8569813
ZY		 375 while (1) {
376 cache = btrfs_lookup_first_block_group(root->fs_info, last);
0f9dd46c
JB		 377 if (!cache)
378 break;
96b5179d 379
c286ac48 380 spin_lock(&cache->lock);
96b5179d
CM		 381 last = cache->key.objectid + cache->key.offset;
382 used = btrfs_block_group_used(&cache->item);
383
d2fb3437
YZ		 384 if ((full_search || !cache->ro) &&
385 block_group_bits(cache, BTRFS_BLOCK_GROUP_METADATA)) {
e8569813 386 if (used + cache->pinned + cache->reserved <
d2fb3437
YZ		 387 div_factor(cache->key.offset, factor)) {
388 group_start = cache->key.objectid;
c286ac48 389 spin_unlock(&cache->lock);
fa9c0d79 390 btrfs_put_block_group(cache);
8790d502
CM		 391 goto found;
392 }
6324fbf3 393 }
c286ac48 394 spin_unlock(&cache->lock);
fa9c0d79 395 btrfs_put_block_group(cache);
de428b63 396 cond_resched();
cd1bc465 397 }
0ef3e66b
CM		 398 if (!wrapped) {
399 last = search_start;
400 wrapped = 1;
401 goto again;
402 }
403 if (!full_search && factor < 10) {
be744175 404 last = search_start;
31f3c99b 405 full_search = 1;
0ef3e66b 406 factor = 10;
31f3c99b
CM		 407 goto again;
408 }
be744175 409found:
d2fb3437 410 return group_start;
925baedd 411}
0f9dd46c 412
e02119d5 413/* simple helper to search for an existing extent at a given offset */
31840ae1 414int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len)
e02119d5
CM		 415{
416 int ret;
417 struct btrfs_key key;
31840ae1 418 struct btrfs_path *path;
e02119d5 419
31840ae1
ZY		 420 path = btrfs_alloc_path();
421 BUG_ON(!path);
e02119d5
CM		 422 key.objectid = start;
423 key.offset = len;
424 btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
425 ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path,
426 0, 0);
31840ae1 427 btrfs_free_path(path);
7bb86316
CM		 428 return ret;
429}
430
d8d5f3e1
CM		 431/*
432 * Back reference rules. Back refs have three main goals:
433 *
434 * 1) differentiate between all holders of references to an extent so that
435 * when a reference is dropped we can make sure it was a valid reference
436 * before freeing the extent.
437 *
438 * 2) Provide enough information to quickly find the holders of an extent
439 * if we notice a given block is corrupted or bad.
440 *
441 * 3) Make it easy to migrate blocks for FS shrinking or storage pool
442 * maintenance. This is actually the same as #2, but with a slightly
443 * different use case.
444 *
5d4f98a2
YZ		 445 * There are two kinds of back refs. The implicit back refs is optimized
446 * for pointers in non-shared tree blocks. For a given pointer in a block,
447 * back refs of this kind provide information about the block's owner tree
448 * and the pointer's key. These information allow us to find the block by
449 * b-tree searching. The full back refs is for pointers in tree blocks not
450 * referenced by their owner trees. The location of tree block is recorded
451 * in the back refs. Actually the full back refs is generic, and can be
452 * used in all cases the implicit back refs is used. The major shortcoming
453 * of the full back refs is its overhead. Every time a tree block gets
454 * COWed, we have to update back refs entry for all pointers in it.
455 *
456 * For a newly allocated tree block, we use implicit back refs for
457 * pointers in it. This means most tree related operations only involve
458 * implicit back refs. For a tree block created in old transaction, the
459 * only way to drop a reference to it is COW it. So we can detect the
460 * event that tree block loses its owner tree's reference and do the
461 * back refs conversion.
462 *
463 * When a tree block is COW'd through a tree, there are four cases:
464 *
465 * The reference count of the block is one and the tree is the block's
466 * owner tree. Nothing to do in this case.
467 *
468 * The reference count of the block is one and the tree is not the
469 * block's owner tree. In this case, full back refs is used for pointers
470 * in the block. Remove these full back refs, add implicit back refs for
471 * every pointers in the new block.
472 *
473 * The reference count of the block is greater than one and the tree is
474 * the block's owner tree. In this case, implicit back refs is used for
475 * pointers in the block. Add full back refs for every pointers in the
476 * block, increase lower level extents' reference counts. The original
477 * implicit back refs are entailed to the new block.
478 *
479 * The reference count of the block is greater than one and the tree is
480 * not the block's owner tree. Add implicit back refs for every pointer in
481 * the new block, increase lower level extents' reference count.
482 *
483 * Back Reference Key composing:
484 *
485 * The key objectid corresponds to the first byte in the extent,
486 * The key type is used to differentiate between types of back refs.
487 * There are different meanings of the key offset for different types
488 * of back refs.
489 *
d8d5f3e1
CM		 490 * File extents can be referenced by:
491 *
492 * - multiple snapshots, subvolumes, or different generations in one subvol
31840ae1 493 * - different files inside a single subvolume
d8d5f3e1
CM		 494 * - different offsets inside a file (bookend extents in file.c)
495 *
5d4f98a2 496 * The extent ref structure for the implicit back refs has fields for:
d8d5f3e1
CM		 497 *
498 * - Objectid of the subvolume root
d8d5f3e1 499 * - objectid of the file holding the reference
5d4f98a2
YZ		 500 * - original offset in the file
501 * - how many bookend extents
d8d5f3e1 502 *
5d4f98a2
YZ		 503 * The key offset for the implicit back refs is hash of the first
504 * three fields.
d8d5f3e1 505 *
5d4f98a2 506 * The extent ref structure for the full back refs has field for:
d8d5f3e1 507 *
5d4f98a2 508 * - number of pointers in the tree leaf
d8d5f3e1 509 *
5d4f98a2
YZ		 510 * The key offset for the implicit back refs is the first byte of
511 * the tree leaf
d8d5f3e1 512 *
5d4f98a2
YZ		 513 * When a file extent is allocated, The implicit back refs is used.
514 * the fields are filled in:
d8d5f3e1 515 *
5d4f98a2 516 * (root_key.objectid, inode objectid, offset in file, 1)
d8d5f3e1 517 *
5d4f98a2
YZ		 518 * When a file extent is removed file truncation, we find the
519 * corresponding implicit back refs and check the following fields:
d8d5f3e1 520 *
5d4f98a2 521 * (btrfs_header_owner(leaf), inode objectid, offset in file)
d8d5f3e1 522 *
5d4f98a2 523 * Btree extents can be referenced by:
d8d5f3e1 524 *
5d4f98a2 525 * - Different subvolumes
d8d5f3e1 526 *
5d4f98a2
YZ		 527 * Both the implicit back refs and the full back refs for tree blocks
528 * only consist of key. The key offset for the implicit back refs is
529 * objectid of block's owner tree. The key offset for the full back refs
530 * is the first byte of parent block.
d8d5f3e1 531 *
5d4f98a2
YZ		 532 * When implicit back refs is used, information about the lowest key and
533 * level of the tree block are required. These information are stored in
534 * tree block info structure.
d8d5f3e1 535 */
31840ae1 536
5d4f98a2
YZ		 537#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
538static int convert_extent_item_v0(struct btrfs_trans_handle *trans,
539 struct btrfs_root *root,
540 struct btrfs_path *path,
541 u64 owner, u32 extra_size)
7bb86316 542{
5d4f98a2
YZ		 543 struct btrfs_extent_item *item;
544 struct btrfs_extent_item_v0 *ei0;
545 struct btrfs_extent_ref_v0 *ref0;
546 struct btrfs_tree_block_info *bi;
547 struct extent_buffer *leaf;
7bb86316 548 struct btrfs_key key;
5d4f98a2
YZ		 549 struct btrfs_key found_key;
550 u32 new_size = sizeof(*item);
551 u64 refs;
552 int ret;
553
554 leaf = path->nodes[0];
555 BUG_ON(btrfs_item_size_nr(leaf, path->slots[0]) != sizeof(*ei0));
556
557 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
558 ei0 = btrfs_item_ptr(leaf, path->slots[0],
559 struct btrfs_extent_item_v0);
560 refs = btrfs_extent_refs_v0(leaf, ei0);
561
562 if (owner == (u64)-1) {
563 while (1) {
564 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
565 ret = btrfs_next_leaf(root, path);
566 if (ret < 0)
567 return ret;
568 BUG_ON(ret > 0);
569 leaf = path->nodes[0];
570 }
571 btrfs_item_key_to_cpu(leaf, &found_key,
572 path->slots[0]);
573 BUG_ON(key.objectid != found_key.objectid);
574 if (found_key.type != BTRFS_EXTENT_REF_V0_KEY) {
575 path->slots[0]++;
576 continue;
577 }
578 ref0 = btrfs_item_ptr(leaf, path->slots[0],
579 struct btrfs_extent_ref_v0);
580 owner = btrfs_ref_objectid_v0(leaf, ref0);
581 break;
582 }
583 }
584 btrfs_release_path(root, path);
585
586 if (owner < BTRFS_FIRST_FREE_OBJECTID)
587 new_size += sizeof(*bi);
588
589 new_size -= sizeof(*ei0);
590 ret = btrfs_search_slot(trans, root, &key, path,
591 new_size + extra_size, 1);
592 if (ret < 0)
593 return ret;
594 BUG_ON(ret);
595
596 ret = btrfs_extend_item(trans, root, path, new_size);
597 BUG_ON(ret);
598
599 leaf = path->nodes[0];
600 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
601 btrfs_set_extent_refs(leaf, item, refs);
602 /* FIXME: get real generation */
603 btrfs_set_extent_generation(leaf, item, 0);
604 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
605 btrfs_set_extent_flags(leaf, item,
606 BTRFS_EXTENT_FLAG_TREE_BLOCK |
607 BTRFS_BLOCK_FLAG_FULL_BACKREF);
608 bi = (struct btrfs_tree_block_info *)(item + 1);
609 /* FIXME: get first key of the block */
610 memset_extent_buffer(leaf, 0, (unsigned long)bi, sizeof(*bi));
611 btrfs_set_tree_block_level(leaf, bi, (int)owner);
612 } else {
613 btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_DATA);
614 }
615 btrfs_mark_buffer_dirty(leaf);
616 return 0;
617}
618#endif
619
620static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
621{
622 u32 high_crc = ~(u32)0;
623 u32 low_crc = ~(u32)0;
624 __le64 lenum;
625
626 lenum = cpu_to_le64(root_objectid);
163e783e 627 high_crc = crc32c(high_crc, &lenum, sizeof(lenum));
5d4f98a2 628 lenum = cpu_to_le64(owner);
163e783e 629 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
5d4f98a2 630 lenum = cpu_to_le64(offset);
163e783e 631 low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
5d4f98a2
YZ		 632
633 return ((u64)high_crc << 31) ^ (u64)low_crc;
634}
635
636static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
637 struct btrfs_extent_data_ref *ref)
638{
639 return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
640 btrfs_extent_data_ref_objectid(leaf, ref),
641 btrfs_extent_data_ref_offset(leaf, ref));
642}
643
644static int match_extent_data_ref(struct extent_buffer *leaf,
645 struct btrfs_extent_data_ref *ref,
646 u64 root_objectid, u64 owner, u64 offset)
647{
648 if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
649 btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
650 btrfs_extent_data_ref_offset(leaf, ref) != offset)
651 return 0;
652 return 1;
653}
654
655static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
656 struct btrfs_root *root,
657 struct btrfs_path *path,
658 u64 bytenr, u64 parent,
659 u64 root_objectid,
660 u64 owner, u64 offset)
661{
662 struct btrfs_key key;
663 struct btrfs_extent_data_ref *ref;
31840ae1 664 struct extent_buffer *leaf;
5d4f98a2 665 u32 nritems;
74493f7a 666 int ret;
5d4f98a2
YZ		 667 int recow;
668 int err = -ENOENT;
74493f7a 669
31840ae1 670 key.objectid = bytenr;
5d4f98a2
YZ		 671 if (parent) {
672 key.type = BTRFS_SHARED_DATA_REF_KEY;
673 key.offset = parent;
674 } else {
675 key.type = BTRFS_EXTENT_DATA_REF_KEY;
676 key.offset = hash_extent_data_ref(root_objectid,
677 owner, offset);
678 }
679again:
680 recow = 0;
681 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
682 if (ret < 0) {
683 err = ret;
684 goto fail;
685 }
31840ae1 686
5d4f98a2
YZ		 687 if (parent) {
688 if (!ret)
689 return 0;
690#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
691 key.type = BTRFS_EXTENT_REF_V0_KEY;
692 btrfs_release_path(root, path);
693 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
694 if (ret < 0) {
695 err = ret;
696 goto fail;
697 }
698 if (!ret)
699 return 0;
700#endif
701 goto fail;
31840ae1
ZY		 702 }
703
704 leaf = path->nodes[0];
5d4f98a2
YZ		 705 nritems = btrfs_header_nritems(leaf);
706 while (1) {
707 if (path->slots[0] >= nritems) {
708 ret = btrfs_next_leaf(root, path);
709 if (ret < 0)
710 err = ret;
711 if (ret)
712 goto fail;
713
714 leaf = path->nodes[0];
715 nritems = btrfs_header_nritems(leaf);
716 recow = 1;
717 }
718
719 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
720 if (key.objectid != bytenr ||
721 key.type != BTRFS_EXTENT_DATA_REF_KEY)
722 goto fail;
723
724 ref = btrfs_item_ptr(leaf, path->slots[0],
725 struct btrfs_extent_data_ref);
726
727 if (match_extent_data_ref(leaf, ref, root_objectid,
728 owner, offset)) {
729 if (recow) {
730 btrfs_release_path(root, path);
731 goto again;
732 }
733 err = 0;
734 break;
735 }
736 path->slots[0]++;
31840ae1 737 }
5d4f98a2
YZ		 738fail:
739 return err;
31840ae1
ZY		 740}
741
5d4f98a2
YZ		 742static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
743 struct btrfs_root *root,
744 struct btrfs_path *path,
745 u64 bytenr, u64 parent,
746 u64 root_objectid, u64 owner,
747 u64 offset, int refs_to_add)
31840ae1
ZY		 748{
749 struct btrfs_key key;
750 struct extent_buffer *leaf;
5d4f98a2 751 u32 size;
31840ae1
ZY		 752 u32 num_refs;
753 int ret;
74493f7a 754
74493f7a 755 key.objectid = bytenr;
5d4f98a2
YZ		 756 if (parent) {
757 key.type = BTRFS_SHARED_DATA_REF_KEY;
758 key.offset = parent;
759 size = sizeof(struct btrfs_shared_data_ref);
760 } else {
761 key.type = BTRFS_EXTENT_DATA_REF_KEY;
762 key.offset = hash_extent_data_ref(root_objectid,
763 owner, offset);
764 size = sizeof(struct btrfs_extent_data_ref);
765 }
74493f7a 766
5d4f98a2
YZ		 767 ret = btrfs_insert_empty_item(trans, root, path, &key, size);
768 if (ret && ret != -EEXIST)
769 goto fail;
770
771 leaf = path->nodes[0];
772 if (parent) {
773 struct btrfs_shared_data_ref *ref;
31840ae1 774 ref = btrfs_item_ptr(leaf, path->slots[0],
5d4f98a2
YZ		 775 struct btrfs_shared_data_ref);
776 if (ret == 0) {
777 btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
778 } else {
779 num_refs = btrfs_shared_data_ref_count(leaf, ref);
780 num_refs += refs_to_add;
781 btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
31840ae1 782 }
5d4f98a2
YZ		 783 } else {
784 struct btrfs_extent_data_ref *ref;
785 while (ret == -EEXIST) {
786 ref = btrfs_item_ptr(leaf, path->slots[0],
787 struct btrfs_extent_data_ref);
788 if (match_extent_data_ref(leaf, ref, root_objectid,
789 owner, offset))
790 break;
791 btrfs_release_path(root, path);
792 key.offset++;
793 ret = btrfs_insert_empty_item(trans, root, path, &key,
794 size);
795 if (ret && ret != -EEXIST)
796 goto fail;
31840ae1 797
5d4f98a2
YZ		 798 leaf = path->nodes[0];
799 }
800 ref = btrfs_item_ptr(leaf, path->slots[0],
801 struct btrfs_extent_data_ref);
802 if (ret == 0) {
803 btrfs_set_extent_data_ref_root(leaf, ref,
804 root_objectid);
805 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
806 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
807 btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
808 } else {
809 num_refs = btrfs_extent_data_ref_count(leaf, ref);
810 num_refs += refs_to_add;
811 btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
31840ae1 812 }
31840ae1 813 }
5d4f98a2
YZ		 814 btrfs_mark_buffer_dirty(leaf);
815 ret = 0;
816fail:
7bb86316
CM		 817 btrfs_release_path(root, path);
818 return ret;
74493f7a
CM		 819}
820
5d4f98a2
YZ		 821static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
822 struct btrfs_root *root,
823 struct btrfs_path *path,
824 int refs_to_drop)
31840ae1 825{
5d4f98a2
YZ		 826 struct btrfs_key key;
827 struct btrfs_extent_data_ref *ref1 = NULL;
828 struct btrfs_shared_data_ref *ref2 = NULL;
31840ae1 829 struct extent_buffer *leaf;
5d4f98a2 830 u32 num_refs = 0;
31840ae1
ZY		 831 int ret = 0;
832
833 leaf = path->nodes[0];
5d4f98a2
YZ		 834 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
835
836 if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
837 ref1 = btrfs_item_ptr(leaf, path->slots[0],
838 struct btrfs_extent_data_ref);
839 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
840 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
841 ref2 = btrfs_item_ptr(leaf, path->slots[0],
842 struct btrfs_shared_data_ref);
843 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
844#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
845 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
846 struct btrfs_extent_ref_v0 *ref0;
847 ref0 = btrfs_item_ptr(leaf, path->slots[0],
848 struct btrfs_extent_ref_v0);
849 num_refs = btrfs_ref_count_v0(leaf, ref0);
850#endif
851 } else {
852 BUG();
853 }
854
56bec294
CM		 855 BUG_ON(num_refs < refs_to_drop);
856 num_refs -= refs_to_drop;
5d4f98a2 857
31840ae1
ZY		 858 if (num_refs == 0) {
859 ret = btrfs_del_item(trans, root, path);
860 } else {
5d4f98a2
YZ		 861 if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
862 btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
863 else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
864 btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
865#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
866 else {
867 struct btrfs_extent_ref_v0 *ref0;
868 ref0 = btrfs_item_ptr(leaf, path->slots[0],
869 struct btrfs_extent_ref_v0);
870 btrfs_set_ref_count_v0(leaf, ref0, num_refs);
871 }
872#endif
31840ae1
ZY		 873 btrfs_mark_buffer_dirty(leaf);
874 }
31840ae1
ZY		 875 return ret;
876}
877
5d4f98a2
YZ		 878static noinline u32 extent_data_ref_count(struct btrfs_root *root,
879 struct btrfs_path *path,
880 struct btrfs_extent_inline_ref *iref)
15916de8 881{
5d4f98a2
YZ		 882 struct btrfs_key key;
883 struct extent_buffer *leaf;
884 struct btrfs_extent_data_ref *ref1;
885 struct btrfs_shared_data_ref *ref2;
886 u32 num_refs = 0;
887
888 leaf = path->nodes[0];
889 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
890 if (iref) {
891 if (btrfs_extent_inline_ref_type(leaf, iref) ==
892 BTRFS_EXTENT_DATA_REF_KEY) {
893 ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
894 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
895 } else {
896 ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
897 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
898 }
899 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
900 ref1 = btrfs_item_ptr(leaf, path->slots[0],
901 struct btrfs_extent_data_ref);
902 num_refs = btrfs_extent_data_ref_count(leaf, ref1);
903 } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
904 ref2 = btrfs_item_ptr(leaf, path->slots[0],
905 struct btrfs_shared_data_ref);
906 num_refs = btrfs_shared_data_ref_count(leaf, ref2);
907#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
908 } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
909 struct btrfs_extent_ref_v0 *ref0;
910 ref0 = btrfs_item_ptr(leaf, path->slots[0],
911 struct btrfs_extent_ref_v0);
912 num_refs = btrfs_ref_count_v0(leaf, ref0);
4b4e25f2 913#endif
5d4f98a2
YZ		 914 } else {
915 WARN_ON(1);
916 }
917 return num_refs;
918}
15916de8 919
5d4f98a2
YZ		 920static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
921 struct btrfs_root *root,
922 struct btrfs_path *path,
923 u64 bytenr, u64 parent,
924 u64 root_objectid)
1f3c79a2 925{
5d4f98a2 926 struct btrfs_key key;
1f3c79a2 927 int ret;
1f3c79a2 928
5d4f98a2
YZ		 929 key.objectid = bytenr;
930 if (parent) {
931 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
932 key.offset = parent;
933 } else {
934 key.type = BTRFS_TREE_BLOCK_REF_KEY;
935 key.offset = root_objectid;
1f3c79a2
LH		 936 }
937
5d4f98a2
YZ		 938 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
939 if (ret > 0)
940 ret = -ENOENT;
941#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
942 if (ret == -ENOENT && parent) {
943 btrfs_release_path(root, path);
944 key.type = BTRFS_EXTENT_REF_V0_KEY;
945 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
946 if (ret > 0)
947 ret = -ENOENT;
948 }
1f3c79a2 949#endif
5d4f98a2 950 return ret;
1f3c79a2
LH		 951}
952
5d4f98a2
YZ		 953static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
954 struct btrfs_root *root,
955 struct btrfs_path *path,
956 u64 bytenr, u64 parent,
957 u64 root_objectid)
31840ae1 958{
5d4f98a2 959 struct btrfs_key key;
31840ae1 960 int ret;
31840ae1 961
5d4f98a2
YZ		 962 key.objectid = bytenr;
963 if (parent) {
964 key.type = BTRFS_SHARED_BLOCK_REF_KEY;
965 key.offset = parent;
966 } else {
967 key.type = BTRFS_TREE_BLOCK_REF_KEY;
968 key.offset = root_objectid;
969 }
970
971 ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
972 btrfs_release_path(root, path);
31840ae1
ZY		 973 return ret;
974}
975
5d4f98a2 976static inline int extent_ref_type(u64 parent, u64 owner)
31840ae1 977{
5d4f98a2
YZ		 978 int type;
979 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
980 if (parent > 0)
981 type = BTRFS_SHARED_BLOCK_REF_KEY;
982 else
983 type = BTRFS_TREE_BLOCK_REF_KEY;
984 } else {
985 if (parent > 0)
986 type = BTRFS_SHARED_DATA_REF_KEY;
987 else
988 type = BTRFS_EXTENT_DATA_REF_KEY;
989 }
990 return type;
31840ae1 991}
56bec294 992
2c47e605
YZ		 993static int find_next_key(struct btrfs_path *path, int level,
994 struct btrfs_key *key)
56bec294 995
02217ed2 996{
2c47e605 997 for (; level < BTRFS_MAX_LEVEL; level++) {
5d4f98a2
YZ		 998 if (!path->nodes[level])
999 break;
5d4f98a2
YZ		 1000 if (path->slots[level] + 1 >=
1001 btrfs_header_nritems(path->nodes[level]))
1002 continue;
1003 if (level == 0)
1004 btrfs_item_key_to_cpu(path->nodes[level], key,
1005 path->slots[level] + 1);
1006 else
1007 btrfs_node_key_to_cpu(path->nodes[level], key,
1008 path->slots[level] + 1);
1009 return 0;
1010 }
1011 return 1;
1012}
037e6390 1013
5d4f98a2
YZ		 1014/*
1015 * look for inline back ref. if back ref is found, *ref_ret is set
1016 * to the address of inline back ref, and 0 is returned.
1017 *
1018 * if back ref isn't found, *ref_ret is set to the address where it
1019 * should be inserted, and -ENOENT is returned.
1020 *
1021 * if insert is true and there are too many inline back refs, the path
1022 * points to the extent item, and -EAGAIN is returned.
1023 *
1024 * NOTE: inline back refs are ordered in the same way that back ref
1025 * items in the tree are ordered.
1026 */
1027static noinline_for_stack
1028int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
1029 struct btrfs_root *root,
1030 struct btrfs_path *path,
1031 struct btrfs_extent_inline_ref **ref_ret,
1032 u64 bytenr, u64 num_bytes,
1033 u64 parent, u64 root_objectid,
1034 u64 owner, u64 offset, int insert)
1035{
1036 struct btrfs_key key;
1037 struct extent_buffer *leaf;
1038 struct btrfs_extent_item *ei;
1039 struct btrfs_extent_inline_ref *iref;
1040 u64 flags;
1041 u64 item_size;
1042 unsigned long ptr;
1043 unsigned long end;
1044 int extra_size;
1045 int type;
1046 int want;
1047 int ret;
1048 int err = 0;
26b8003f 1049
db94535d 1050 key.objectid = bytenr;
31840ae1 1051 key.type = BTRFS_EXTENT_ITEM_KEY;
56bec294 1052 key.offset = num_bytes;
31840ae1 1053
5d4f98a2
YZ		 1054 want = extent_ref_type(parent, owner);
1055 if (insert) {
1056 extra_size = btrfs_extent_inline_ref_size(want);
85d4198e 1057 path->keep_locks = 1;
5d4f98a2
YZ		 1058 } else
1059 extra_size = -1;
1060 ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
b9473439 1061 if (ret < 0) {
5d4f98a2
YZ		 1062 err = ret;
1063 goto out;
1064 }
1065 BUG_ON(ret);
1066
1067 leaf = path->nodes[0];
1068 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1069#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1070 if (item_size < sizeof(*ei)) {
1071 if (!insert) {
1072 err = -ENOENT;
1073 goto out;
1074 }
1075 ret = convert_extent_item_v0(trans, root, path, owner,
1076 extra_size);
1077 if (ret < 0) {
1078 err = ret;
1079 goto out;
1080 }
1081 leaf = path->nodes[0];
1082 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1083 }
1084#endif
1085 BUG_ON(item_size < sizeof(*ei));
1086
5d4f98a2
YZ		 1087 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1088 flags = btrfs_extent_flags(leaf, ei);
1089
1090 ptr = (unsigned long)(ei + 1);
1091 end = (unsigned long)ei + item_size;
1092
1093 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
1094 ptr += sizeof(struct btrfs_tree_block_info);
1095 BUG_ON(ptr > end);
1096 } else {
1097 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_DATA));
1098 }
1099
1100 err = -ENOENT;
1101 while (1) {
1102 if (ptr >= end) {
1103 WARN_ON(ptr > end);
1104 break;
1105 }
1106 iref = (struct btrfs_extent_inline_ref *)ptr;
1107 type = btrfs_extent_inline_ref_type(leaf, iref);
1108 if (want < type)
1109 break;
1110 if (want > type) {
1111 ptr += btrfs_extent_inline_ref_size(type);
1112 continue;
1113 }
1114
1115 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1116 struct btrfs_extent_data_ref *dref;
1117 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1118 if (match_extent_data_ref(leaf, dref, root_objectid,
1119 owner, offset)) {
1120 err = 0;
1121 break;
1122 }
1123 if (hash_extent_data_ref_item(leaf, dref) <
1124 hash_extent_data_ref(root_objectid, owner, offset))
1125 break;
1126 } else {
1127 u64 ref_offset;
1128 ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1129 if (parent > 0) {
1130 if (parent == ref_offset) {
1131 err = 0;
1132 break;
1133 }
1134 if (ref_offset < parent)
1135 break;
1136 } else {
1137 if (root_objectid == ref_offset) {
1138 err = 0;
1139 break;
1140 }
1141 if (ref_offset < root_objectid)
1142 break;
1143 }
1144 }
1145 ptr += btrfs_extent_inline_ref_size(type);
1146 }
1147 if (err == -ENOENT && insert) {
1148 if (item_size + extra_size >=
1149 BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
1150 err = -EAGAIN;
1151 goto out;
1152 }
1153 /*
1154 * To add new inline back ref, we have to make sure
1155 * there is no corresponding back ref item.
1156 * For simplicity, we just do not add new inline back
1157 * ref if there is any kind of item for this block
1158 */
2c47e605
YZ		 1159 if (find_next_key(path, 0, &key) == 0 &&
1160 key.objectid == bytenr &&
85d4198e 1161 key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
5d4f98a2
YZ		 1162 err = -EAGAIN;
1163 goto out;
1164 }
1165 }
1166 *ref_ret = (struct btrfs_extent_inline_ref *)ptr;
1167out:
85d4198e 1168 if (insert) {
5d4f98a2
YZ		 1169 path->keep_locks = 0;
1170 btrfs_unlock_up_safe(path, 1);
1171 }
1172 return err;
1173}
1174
1175/*
1176 * helper to add new inline back ref
1177 */
1178static noinline_for_stack
1179int setup_inline_extent_backref(struct btrfs_trans_handle *trans,
1180 struct btrfs_root *root,
1181 struct btrfs_path *path,
1182 struct btrfs_extent_inline_ref *iref,
1183 u64 parent, u64 root_objectid,
1184 u64 owner, u64 offset, int refs_to_add,
1185 struct btrfs_delayed_extent_op *extent_op)
1186{
1187 struct extent_buffer *leaf;
1188 struct btrfs_extent_item *ei;
1189 unsigned long ptr;
1190 unsigned long end;
1191 unsigned long item_offset;
1192 u64 refs;
1193 int size;
1194 int type;
1195 int ret;
1196
1197 leaf = path->nodes[0];
1198 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1199 item_offset = (unsigned long)iref - (unsigned long)ei;
1200
1201 type = extent_ref_type(parent, owner);
1202 size = btrfs_extent_inline_ref_size(type);
1203
1204 ret = btrfs_extend_item(trans, root, path, size);
1205 BUG_ON(ret);
1206
1207 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1208 refs = btrfs_extent_refs(leaf, ei);
1209 refs += refs_to_add;
1210 btrfs_set_extent_refs(leaf, ei, refs);
1211 if (extent_op)
1212 __run_delayed_extent_op(extent_op, leaf, ei);
1213
1214 ptr = (unsigned long)ei + item_offset;
1215 end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
1216 if (ptr < end - size)
1217 memmove_extent_buffer(leaf, ptr + size, ptr,
1218 end - size - ptr);
1219
1220 iref = (struct btrfs_extent_inline_ref *)ptr;
1221 btrfs_set_extent_inline_ref_type(leaf, iref, type);
1222 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1223 struct btrfs_extent_data_ref *dref;
1224 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1225 btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
1226 btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
1227 btrfs_set_extent_data_ref_offset(leaf, dref, offset);
1228 btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
1229 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1230 struct btrfs_shared_data_ref *sref;
1231 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1232 btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
1233 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1234 } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
1235 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
1236 } else {
1237 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
1238 }
1239 btrfs_mark_buffer_dirty(leaf);
1240 return 0;
1241}
1242
1243static int lookup_extent_backref(struct btrfs_trans_handle *trans,
1244 struct btrfs_root *root,
1245 struct btrfs_path *path,
1246 struct btrfs_extent_inline_ref **ref_ret,
1247 u64 bytenr, u64 num_bytes, u64 parent,
1248 u64 root_objectid, u64 owner, u64 offset)
1249{
1250 int ret;
1251
1252 ret = lookup_inline_extent_backref(trans, root, path, ref_ret,
1253 bytenr, num_bytes, parent,
1254 root_objectid, owner, offset, 0);
1255 if (ret != -ENOENT)
54aa1f4d 1256 return ret;
5d4f98a2
YZ		 1257
1258 btrfs_release_path(root, path);
1259 *ref_ret = NULL;
1260
1261 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1262 ret = lookup_tree_block_ref(trans, root, path, bytenr, parent,
1263 root_objectid);
1264 } else {
1265 ret = lookup_extent_data_ref(trans, root, path, bytenr, parent,
1266 root_objectid, owner, offset);
b9473439 1267 }
5d4f98a2
YZ		 1268 return ret;
1269}
31840ae1 1270
5d4f98a2
YZ		 1271/*
1272 * helper to update/remove inline back ref
1273 */
1274static noinline_for_stack
1275int update_inline_extent_backref(struct btrfs_trans_handle *trans,
1276 struct btrfs_root *root,
1277 struct btrfs_path *path,
1278 struct btrfs_extent_inline_ref *iref,
1279 int refs_to_mod,
1280 struct btrfs_delayed_extent_op *extent_op)
1281{
1282 struct extent_buffer *leaf;
1283 struct btrfs_extent_item *ei;
1284 struct btrfs_extent_data_ref *dref = NULL;
1285 struct btrfs_shared_data_ref *sref = NULL;
1286 unsigned long ptr;
1287 unsigned long end;
1288 u32 item_size;
1289 int size;
1290 int type;
1291 int ret;
1292 u64 refs;
1293
1294 leaf = path->nodes[0];
1295 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1296 refs = btrfs_extent_refs(leaf, ei);
1297 WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
1298 refs += refs_to_mod;
1299 btrfs_set_extent_refs(leaf, ei, refs);
1300 if (extent_op)
1301 __run_delayed_extent_op(extent_op, leaf, ei);
1302
1303 type = btrfs_extent_inline_ref_type(leaf, iref);
1304
1305 if (type == BTRFS_EXTENT_DATA_REF_KEY) {
1306 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1307 refs = btrfs_extent_data_ref_count(leaf, dref);
1308 } else if (type == BTRFS_SHARED_DATA_REF_KEY) {
1309 sref = (struct btrfs_shared_data_ref *)(iref + 1);
1310 refs = btrfs_shared_data_ref_count(leaf, sref);
1311 } else {
1312 refs = 1;
1313 BUG_ON(refs_to_mod != -1);
56bec294 1314 }
31840ae1 1315
5d4f98a2
YZ		 1316 BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
1317 refs += refs_to_mod;
1318
1319 if (refs > 0) {
1320 if (type == BTRFS_EXTENT_DATA_REF_KEY)
1321 btrfs_set_extent_data_ref_count(leaf, dref, refs);
1322 else
1323 btrfs_set_shared_data_ref_count(leaf, sref, refs);
1324 } else {
1325 size = btrfs_extent_inline_ref_size(type);
1326 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1327 ptr = (unsigned long)iref;
1328 end = (unsigned long)ei + item_size;
1329 if (ptr + size < end)
1330 memmove_extent_buffer(leaf, ptr, ptr + size,
1331 end - ptr - size);
1332 item_size -= size;
1333 ret = btrfs_truncate_item(trans, root, path, item_size, 1);
1334 BUG_ON(ret);
1335 }
1336 btrfs_mark_buffer_dirty(leaf);
1337 return 0;
1338}
1339
1340static noinline_for_stack
1341int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
1342 struct btrfs_root *root,
1343 struct btrfs_path *path,
1344 u64 bytenr, u64 num_bytes, u64 parent,
1345 u64 root_objectid, u64 owner,
1346 u64 offset, int refs_to_add,
1347 struct btrfs_delayed_extent_op *extent_op)
1348{
1349 struct btrfs_extent_inline_ref *iref;
1350 int ret;
1351
1352 ret = lookup_inline_extent_backref(trans, root, path, &iref,
1353 bytenr, num_bytes, parent,
1354 root_objectid, owner, offset, 1);
1355 if (ret == 0) {
1356 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
1357 ret = update_inline_extent_backref(trans, root, path, iref,
1358 refs_to_add, extent_op);
1359 } else if (ret == -ENOENT) {
1360 ret = setup_inline_extent_backref(trans, root, path, iref,
1361 parent, root_objectid,
1362 owner, offset, refs_to_add,
1363 extent_op);
771ed689 1364 }
5d4f98a2
YZ		 1365 return ret;
1366}
31840ae1 1367
5d4f98a2
YZ		 1368static int insert_extent_backref(struct btrfs_trans_handle *trans,
1369 struct btrfs_root *root,
1370 struct btrfs_path *path,
1371 u64 bytenr, u64 parent, u64 root_objectid,
1372 u64 owner, u64 offset, int refs_to_add)
1373{
1374 int ret;
1375 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1376 BUG_ON(refs_to_add != 1);
1377 ret = insert_tree_block_ref(trans, root, path, bytenr,
1378 parent, root_objectid);
1379 } else {
1380 ret = insert_extent_data_ref(trans, root, path, bytenr,
1381 parent, root_objectid,
1382 owner, offset, refs_to_add);
1383 }
1384 return ret;
1385}
56bec294 1386
5d4f98a2
YZ		 1387static int remove_extent_backref(struct btrfs_trans_handle *trans,
1388 struct btrfs_root *root,
1389 struct btrfs_path *path,
1390 struct btrfs_extent_inline_ref *iref,
1391 int refs_to_drop, int is_data)
1392{
1393 int ret;
b9473439 1394
5d4f98a2
YZ		 1395 BUG_ON(!is_data && refs_to_drop != 1);
1396 if (iref) {
1397 ret = update_inline_extent_backref(trans, root, path, iref,
1398 -refs_to_drop, NULL);
1399 } else if (is_data) {
1400 ret = remove_extent_data_ref(trans, root, path, refs_to_drop);
1401 } else {
1402 ret = btrfs_del_item(trans, root, path);
1403 }
1404 return ret;
1405}
1406
1407#ifdef BIO_RW_DISCARD
1408static void btrfs_issue_discard(struct block_device *bdev,
1409 u64 start, u64 len)
1410{
1411 blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_KERNEL);
1412}
1413#endif
1414
1415static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
1416 u64 num_bytes)
1417{
1418#ifdef BIO_RW_DISCARD
1419 int ret;
1420 u64 map_length = num_bytes;
1421 struct btrfs_multi_bio *multi = NULL;
1422
1423 /* Tell the block device(s) that the sectors can be discarded */
1424 ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
1425 bytenr, &map_length, &multi, 0);
1426 if (!ret) {
1427 struct btrfs_bio_stripe *stripe = multi->stripes;
1428 int i;
1429
1430 if (map_length > num_bytes)
1431 map_length = num_bytes;
1432
1433 for (i = 0; i < multi->num_stripes; i++, stripe++) {
1434 btrfs_issue_discard(stripe->dev->bdev,
1435 stripe->physical,
1436 map_length);
1437 }
1438 kfree(multi);
1439 }
1440
1441 return ret;
1442#else
1443 return 0;
1444#endif
1445}
1446
1447int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1448 struct btrfs_root *root,
1449 u64 bytenr, u64 num_bytes, u64 parent,
1450 u64 root_objectid, u64 owner, u64 offset)
1451{
1452 int ret;
1453 BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID &&
1454 root_objectid == BTRFS_TREE_LOG_OBJECTID);
1455
1456 if (owner < BTRFS_FIRST_FREE_OBJECTID) {
1457 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
1458 parent, root_objectid, (int)owner,
1459 BTRFS_ADD_DELAYED_REF, NULL);
1460 } else {
1461 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
1462 parent, root_objectid, owner, offset,
1463 BTRFS_ADD_DELAYED_REF, NULL);
1464 }
1465 return ret;
1466}
1467
1468static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
1469 struct btrfs_root *root,
1470 u64 bytenr, u64 num_bytes,
1471 u64 parent, u64 root_objectid,
1472 u64 owner, u64 offset, int refs_to_add,
1473 struct btrfs_delayed_extent_op *extent_op)
1474{
1475 struct btrfs_path *path;
1476 struct extent_buffer *leaf;
1477 struct btrfs_extent_item *item;
1478 u64 refs;
1479 int ret;
1480 int err = 0;
1481
1482 path = btrfs_alloc_path();
1483 if (!path)
1484 return -ENOMEM;
1485
1486 path->reada = 1;
1487 path->leave_spinning = 1;
1488 /* this will setup the path even if it fails to insert the back ref */
1489 ret = insert_inline_extent_backref(trans, root->fs_info->extent_root,
1490 path, bytenr, num_bytes, parent,
1491 root_objectid, owner, offset,
1492 refs_to_add, extent_op);
1493 if (ret == 0)
1494 goto out;
1495
1496 if (ret != -EAGAIN) {
1497 err = ret;
1498 goto out;
1499 }
1500
1501 leaf = path->nodes[0];
1502 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1503 refs = btrfs_extent_refs(leaf, item);
1504 btrfs_set_extent_refs(leaf, item, refs + refs_to_add);
1505 if (extent_op)
1506 __run_delayed_extent_op(extent_op, leaf, item);
56bec294 1507
5d4f98a2 1508 btrfs_mark_buffer_dirty(leaf);
56bec294
CM		 1509 btrfs_release_path(root->fs_info->extent_root, path);
1510
1511 path->reada = 1;
b9473439
CM		 1512 path->leave_spinning = 1;
1513
56bec294
CM		 1514 /* now insert the actual backref */
1515 ret = insert_extent_backref(trans, root->fs_info->extent_root,
5d4f98a2
YZ		 1516 path, bytenr, parent, root_objectid,
1517 owner, offset, refs_to_add);
56bec294 1518 BUG_ON(ret);
5d4f98a2 1519out:
56bec294 1520 btrfs_free_path(path);
5d4f98a2 1521 return err;
56bec294
CM		 1522}
1523
5d4f98a2
YZ		 1524static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
1525 struct btrfs_root *root,
1526 struct btrfs_delayed_ref_node *node,
1527 struct btrfs_delayed_extent_op *extent_op,
1528 int insert_reserved)
56bec294 1529{
5d4f98a2
YZ		 1530 int ret = 0;
1531 struct btrfs_delayed_data_ref *ref;
1532 struct btrfs_key ins;
1533 u64 parent = 0;
1534 u64 ref_root = 0;
1535 u64 flags = 0;
1536
1537 ins.objectid = node->bytenr;
1538 ins.offset = node->num_bytes;
1539 ins.type = BTRFS_EXTENT_ITEM_KEY;
1540
1541 ref = btrfs_delayed_node_to_data_ref(node);
1542 if (node->type == BTRFS_SHARED_DATA_REF_KEY)
1543 parent = ref->parent;
1544 else
1545 ref_root = ref->root;
1546
1547 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
1548 if (extent_op) {
1549 BUG_ON(extent_op->update_key);
1550 flags |= extent_op->flags_to_set;
1551 }
1552 ret = alloc_reserved_file_extent(trans, root,
1553 parent, ref_root, flags,
1554 ref->objectid, ref->offset,
1555 &ins, node->ref_mod);
1556 update_reserved_extents(root, ins.objectid, ins.offset, 0);
1557 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
1558 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
1559 node->num_bytes, parent,
1560 ref_root, ref->objectid,
1561 ref->offset, node->ref_mod,
1562 extent_op);
1563 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
1564 ret = __btrfs_free_extent(trans, root, node->bytenr,
1565 node->num_bytes, parent,
1566 ref_root, ref->objectid,
1567 ref->offset, node->ref_mod,
1568 extent_op);
1569 } else {
1570 BUG();
1571 }
1572 return ret;
1573}
1574
1575static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op,
1576 struct extent_buffer *leaf,
1577 struct btrfs_extent_item *ei)
1578{
1579 u64 flags = btrfs_extent_flags(leaf, ei);
1580 if (extent_op->update_flags) {
1581 flags |= extent_op->flags_to_set;
1582 btrfs_set_extent_flags(leaf, ei, flags);
1583 }
1584
1585 if (extent_op->update_key) {
1586 struct btrfs_tree_block_info *bi;
1587 BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK));
1588 bi = (struct btrfs_tree_block_info *)(ei + 1);
1589 btrfs_set_tree_block_key(leaf, bi, &extent_op->key);
1590 }
1591}
1592
1593static int run_delayed_extent_op(struct btrfs_trans_handle *trans,
1594 struct btrfs_root *root,
1595 struct btrfs_delayed_ref_node *node,
1596 struct btrfs_delayed_extent_op *extent_op)
1597{
1598 struct btrfs_key key;
1599 struct btrfs_path *path;
1600 struct btrfs_extent_item *ei;
1601 struct extent_buffer *leaf;
1602 u32 item_size;
56bec294 1603 int ret;
5d4f98a2
YZ		 1604 int err = 0;
1605
1606 path = btrfs_alloc_path();
1607 if (!path)
1608 return -ENOMEM;
1609
1610 key.objectid = node->bytenr;
1611 key.type = BTRFS_EXTENT_ITEM_KEY;
1612 key.offset = node->num_bytes;
1613
1614 path->reada = 1;
1615 path->leave_spinning = 1;
1616 ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key,
1617 path, 0, 1);
1618 if (ret < 0) {
1619 err = ret;
1620 goto out;
1621 }
1622 if (ret > 0) {
1623 err = -EIO;
1624 goto out;
1625 }
1626
1627 leaf = path->nodes[0];
1628 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1629#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
1630 if (item_size < sizeof(*ei)) {
1631 ret = convert_extent_item_v0(trans, root->fs_info->extent_root,
1632 path, (u64)-1, 0);
1633 if (ret < 0) {
1634 err = ret;
1635 goto out;
1636 }
1637 leaf = path->nodes[0];
1638 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
1639 }
1640#endif
1641 BUG_ON(item_size < sizeof(*ei));
1642 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
1643 __run_delayed_extent_op(extent_op, leaf, ei);
56bec294 1644
5d4f98a2
YZ		 1645 btrfs_mark_buffer_dirty(leaf);
1646out:
1647 btrfs_free_path(path);
1648 return err;
56bec294
CM		 1649}
1650
5d4f98a2
YZ		 1651static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
1652 struct btrfs_root *root,
1653 struct btrfs_delayed_ref_node *node,
1654 struct btrfs_delayed_extent_op *extent_op,
1655 int insert_reserved)
56bec294
CM		 1656{
1657 int ret = 0;
5d4f98a2
YZ		 1658 struct btrfs_delayed_tree_ref *ref;
1659 struct btrfs_key ins;
1660 u64 parent = 0;
1661 u64 ref_root = 0;
56bec294 1662
5d4f98a2
YZ		 1663 ins.objectid = node->bytenr;
1664 ins.offset = node->num_bytes;
1665 ins.type = BTRFS_EXTENT_ITEM_KEY;
56bec294 1666
5d4f98a2
YZ		 1667 ref = btrfs_delayed_node_to_tree_ref(node);
1668 if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
1669 parent = ref->parent;
1670 else
1671 ref_root = ref->root;
1672
1673 BUG_ON(node->ref_mod != 1);
1674 if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
1675 BUG_ON(!extent_op || !extent_op->update_flags ||
1676 !extent_op->update_key);
1677 ret = alloc_reserved_tree_block(trans, root,
1678 parent, ref_root,
1679 extent_op->flags_to_set,
1680 &extent_op->key,
1681 ref->level, &ins);
1682 update_reserved_extents(root, ins.objectid, ins.offset, 0);
1683 } else if (node->action == BTRFS_ADD_DELAYED_REF) {
1684 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
1685 node->num_bytes, parent, ref_root,
1686 ref->level, 0, 1, extent_op);
1687 } else if (node->action == BTRFS_DROP_DELAYED_REF) {
1688 ret = __btrfs_free_extent(trans, root, node->bytenr,
1689 node->num_bytes, parent, ref_root,
1690 ref->level, 0, 1, extent_op);
1691 } else {
1692 BUG();
1693 }
56bec294
CM		 1694 return ret;
1695}
1696
5d4f98a2 1697
56bec294 1698/* helper function to actually process a single delayed ref entry */
5d4f98a2
YZ		 1699static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
1700 struct btrfs_root *root,
1701 struct btrfs_delayed_ref_node *node,
1702 struct btrfs_delayed_extent_op *extent_op,
1703 int insert_reserved)
56bec294
CM		 1704{
1705 int ret;
5d4f98a2 1706 if (btrfs_delayed_ref_is_head(node)) {
56bec294
CM		 1707 struct btrfs_delayed_ref_head *head;
1708 /*
1709 * we've hit the end of the chain and we were supposed
1710 * to insert this extent into the tree. But, it got
1711 * deleted before we ever needed to insert it, so all
1712 * we have to do is clean up the accounting
1713 */
5d4f98a2
YZ		 1714 BUG_ON(extent_op);
1715 head = btrfs_delayed_node_to_head(node);
56bec294 1716 if (insert_reserved) {
5d4f98a2
YZ		 1717 if (head->is_data) {
1718 ret = btrfs_del_csums(trans, root,
1719 node->bytenr,
1720 node->num_bytes);
1721 BUG_ON(ret);
1722 }
1723 btrfs_update_pinned_extents(root, node->bytenr,
1724 node->num_bytes, 1);
56bec294
CM		 1725 update_reserved_extents(root, node->bytenr,
1726 node->num_bytes, 0);
1727 }
56bec294
CM		 1728 mutex_unlock(&head->mutex);
1729 return 0;
1730 }
1731
5d4f98a2
YZ		 1732 if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
1733 node->type == BTRFS_SHARED_BLOCK_REF_KEY)
1734 ret = run_delayed_tree_ref(trans, root, node, extent_op,
1735 insert_reserved);
1736 else if (node->type == BTRFS_EXTENT_DATA_REF_KEY ||
1737 node->type == BTRFS_SHARED_DATA_REF_KEY)
1738 ret = run_delayed_data_ref(trans, root, node, extent_op,
1739 insert_reserved);
1740 else
1741 BUG();
1742 return ret;
56bec294
CM		 1743}
1744
1745static noinline struct btrfs_delayed_ref_node *
1746select_delayed_ref(struct btrfs_delayed_ref_head *head)
1747{
1748 struct rb_node *node;
1749 struct btrfs_delayed_ref_node *ref;
1750 int action = BTRFS_ADD_DELAYED_REF;
1751again:
1752 /*
1753 * select delayed ref of type BTRFS_ADD_DELAYED_REF first.
1754 * this prevents ref count from going down to zero when
1755 * there still are pending delayed ref.
1756 */
1757 node = rb_prev(&head->node.rb_node);
1758 while (1) {
1759 if (!node)
1760 break;
1761 ref = rb_entry(node, struct btrfs_delayed_ref_node,
1762 rb_node);
1763 if (ref->bytenr != head->node.bytenr)
1764 break;
5d4f98a2 1765 if (ref->action == action)
56bec294
CM		 1766 return ref;
1767 node = rb_prev(node);
1768 }
1769 if (action == BTRFS_ADD_DELAYED_REF) {
1770 action = BTRFS_DROP_DELAYED_REF;
1771 goto again;
1772 }
1773 return NULL;
1774}
1775
c3e69d58
CM		 1776static noinline int run_clustered_refs(struct btrfs_trans_handle *trans,
1777 struct btrfs_root *root,
1778 struct list_head *cluster)
56bec294 1779{
56bec294
CM		 1780 struct btrfs_delayed_ref_root *delayed_refs;
1781 struct btrfs_delayed_ref_node *ref;
1782 struct btrfs_delayed_ref_head *locked_ref = NULL;
5d4f98a2 1783 struct btrfs_delayed_extent_op *extent_op;
56bec294 1784 int ret;
c3e69d58 1785 int count = 0;
56bec294 1786 int must_insert_reserved = 0;
56bec294
CM		 1787
1788 delayed_refs = &trans->transaction->delayed_refs;
56bec294
CM		 1789 while (1) {
1790 if (!locked_ref) {
c3e69d58
CM		 1791 /* pick a new head ref from the cluster list */
1792 if (list_empty(cluster))
56bec294 1793 break;
56bec294 1794
c3e69d58
CM		 1795 locked_ref = list_entry(cluster->next,
1796 struct btrfs_delayed_ref_head, cluster);
1797
1798 /* grab the lock that says we are going to process
1799 * all the refs for this head */
1800 ret = btrfs_delayed_ref_lock(trans, locked_ref);
1801
1802 /*
1803 * we may have dropped the spin lock to get the head
1804 * mutex lock, and that might have given someone else
1805 * time to free the head. If that's true, it has been
1806 * removed from our list and we can move on.
1807 */
1808 if (ret == -EAGAIN) {
1809 locked_ref = NULL;
1810 count++;
1811 continue;
56bec294
CM		 1812 }
1813 }
a28ec197 1814
56bec294
CM		 1815 /*
1816 * record the must insert reserved flag before we
1817 * drop the spin lock.
1818 */
1819 must_insert_reserved = locked_ref->must_insert_reserved;
1820 locked_ref->must_insert_reserved = 0;
7bb86316 1821
5d4f98a2
YZ		 1822 extent_op = locked_ref->extent_op;
1823 locked_ref->extent_op = NULL;
1824
56bec294
CM		 1825 /*
1826 * locked_ref is the head node, so we have to go one
1827 * node back for any delayed ref updates
1828 */
56bec294
CM		 1829 ref = select_delayed_ref(locked_ref);
1830 if (!ref) {
1831 /* All delayed refs have been processed, Go ahead
1832 * and send the head node to run_one_delayed_ref,
1833 * so that any accounting fixes can happen
1834 */
1835 ref = &locked_ref->node;
5d4f98a2
YZ		 1836
1837 if (extent_op && must_insert_reserved) {
1838 kfree(extent_op);
1839 extent_op = NULL;
1840 }
1841
1842 if (extent_op) {
1843 spin_unlock(&delayed_refs->lock);
1844
1845 ret = run_delayed_extent_op(trans, root,
1846 ref, extent_op);
1847 BUG_ON(ret);
1848 kfree(extent_op);
1849
1850 cond_resched();
1851 spin_lock(&delayed_refs->lock);
1852 continue;
1853 }
1854
c3e69d58 1855 list_del_init(&locked_ref->cluster);
56bec294
CM		 1856 locked_ref = NULL;
1857 }
02217ed2 1858
56bec294
CM		 1859 ref->in_tree = 0;
1860 rb_erase(&ref->rb_node, &delayed_refs->root);
1861 delayed_refs->num_entries--;
5d4f98a2 1862
56bec294 1863 spin_unlock(&delayed_refs->lock);
925baedd 1864
5d4f98a2 1865 ret = run_one_delayed_ref(trans, root, ref, extent_op,
56bec294
CM		 1866 must_insert_reserved);
1867 BUG_ON(ret);
eb099670 1868
5d4f98a2
YZ		 1869 btrfs_put_delayed_ref(ref);
1870 kfree(extent_op);
c3e69d58 1871 count++;
5d4f98a2 1872
c3e69d58
CM		 1873 cond_resched();
1874 spin_lock(&delayed_refs->lock);
1875 }
1876 return count;
1877}
1878
1879/*
1880 * this starts processing the delayed reference count updates and
1881 * extent insertions we have queued up so far. count can be
1882 * 0, which means to process everything in the tree at the start
1883 * of the run (but not newly added entries), or it can be some target
1884 * number you'd like to process.
1885 */
1886int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
1887 struct btrfs_root *root, unsigned long count)
1888{
1889 struct rb_node *node;
1890 struct btrfs_delayed_ref_root *delayed_refs;
1891 struct btrfs_delayed_ref_node *ref;
1892 struct list_head cluster;
1893 int ret;
1894 int run_all = count == (unsigned long)-1;
1895 int run_most = 0;
1896
1897 if (root == root->fs_info->extent_root)
1898 root = root->fs_info->tree_root;
1899
1900 delayed_refs = &trans->transaction->delayed_refs;
1901 INIT_LIST_HEAD(&cluster);
1902again:
1903 spin_lock(&delayed_refs->lock);
1904 if (count == 0) {
1905 count = delayed_refs->num_entries * 2;
1906 run_most = 1;
1907 }
1908 while (1) {
1909 if (!(run_all || run_most) &&
1910 delayed_refs->num_heads_ready < 64)
1911 break;
eb099670 1912
56bec294 1913 /*
c3e69d58
CM		 1914 * go find something we can process in the rbtree. We start at
1915 * the beginning of the tree, and then build a cluster
1916 * of refs to process starting at the first one we are able to
1917 * lock
56bec294 1918 */
c3e69d58
CM		 1919 ret = btrfs_find_ref_cluster(trans, &cluster,
1920 delayed_refs->run_delayed_start);
1921 if (ret)
56bec294
CM		 1922 break;
1923
c3e69d58
CM		 1924 ret = run_clustered_refs(trans, root, &cluster);
1925 BUG_ON(ret < 0);
1926
1927 count -= min_t(unsigned long, ret, count);
1928
1929 if (count == 0)
1930 break;
eb099670 1931 }
c3e69d58 1932
56bec294 1933 if (run_all) {
56bec294 1934 node = rb_first(&delayed_refs->root);
c3e69d58 1935 if (!node)
56bec294 1936 goto out;
c3e69d58 1937 count = (unsigned long)-1;
e9d0b13b 1938
56bec294
CM		 1939 while (node) {
1940 ref = rb_entry(node, struct btrfs_delayed_ref_node,
1941 rb_node);
1942 if (btrfs_delayed_ref_is_head(ref)) {
1943 struct btrfs_delayed_ref_head *head;
5caf2a00 1944
56bec294
CM		 1945 head = btrfs_delayed_node_to_head(ref);
1946 atomic_inc(&ref->refs);
1947
1948 spin_unlock(&delayed_refs->lock);
1949 mutex_lock(&head->mutex);
1950 mutex_unlock(&head->mutex);
1951
1952 btrfs_put_delayed_ref(ref);
1887be66 1953 cond_resched();
56bec294
CM		 1954 goto again;
1955 }
1956 node = rb_next(node);
1957 }
1958 spin_unlock(&delayed_refs->lock);
56bec294
CM		 1959 schedule_timeout(1);
1960 goto again;
5f39d397 1961 }
54aa1f4d 1962out:
c3e69d58 1963 spin_unlock(&delayed_refs->lock);
a28ec197
CM		 1964 return 0;
1965}
1966
5d4f98a2
YZ		 1967int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
1968 struct btrfs_root *root,
1969 u64 bytenr, u64 num_bytes, u64 flags,
1970 int is_data)
1971{
1972 struct btrfs_delayed_extent_op *extent_op;
1973 int ret;
1974
1975 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
1976 if (!extent_op)
1977 return -ENOMEM;
1978
1979 extent_op->flags_to_set = flags;
1980 extent_op->update_flags = 1;
1981 extent_op->update_key = 0;
1982 extent_op->is_data = is_data ? 1 : 0;
1983
1984 ret = btrfs_add_delayed_extent_op(trans, bytenr, num_bytes, extent_op);
1985 if (ret)
1986 kfree(extent_op);
1987 return ret;
1988}
1989
1990static noinline int check_delayed_ref(struct btrfs_trans_handle *trans,
1991 struct btrfs_root *root,
1992 struct btrfs_path *path,
1993 u64 objectid, u64 offset, u64 bytenr)
1994{
1995 struct btrfs_delayed_ref_head *head;
1996 struct btrfs_delayed_ref_node *ref;
1997 struct btrfs_delayed_data_ref *data_ref;
1998 struct btrfs_delayed_ref_root *delayed_refs;
1999 struct rb_node *node;
2000 int ret = 0;
2001
2002 ret = -ENOENT;
2003 delayed_refs = &trans->transaction->delayed_refs;
2004 spin_lock(&delayed_refs->lock);
2005 head = btrfs_find_delayed_ref_head(trans, bytenr);
2006 if (!head)
2007 goto out;
2008
2009 if (!mutex_trylock(&head->mutex)) {
2010 atomic_inc(&head->node.refs);
2011 spin_unlock(&delayed_refs->lock);
2012
2013 btrfs_release_path(root->fs_info->extent_root, path);
2014
2015 mutex_lock(&head->mutex);
2016 mutex_unlock(&head->mutex);
2017 btrfs_put_delayed_ref(&head->node);
2018 return -EAGAIN;
2019 }
2020
2021 node = rb_prev(&head->node.rb_node);
2022 if (!node)
2023 goto out_unlock;
2024
2025 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2026
2027 if (ref->bytenr != bytenr)
2028 goto out_unlock;
2029
2030 ret = 1;
2031 if (ref->type != BTRFS_EXTENT_DATA_REF_KEY)
2032 goto out_unlock;
2033
2034 data_ref = btrfs_delayed_node_to_data_ref(ref);
2035
2036 node = rb_prev(node);
2037 if (node) {
2038 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
2039 if (ref->bytenr == bytenr)
2040 goto out_unlock;
2041 }
2042
2043 if (data_ref->root != root->root_key.objectid ||
2044 data_ref->objectid != objectid || data_ref->offset != offset)
2045 goto out_unlock;
2046
2047 ret = 0;
2048out_unlock:
2049 mutex_unlock(&head->mutex);
2050out:
2051 spin_unlock(&delayed_refs->lock);
2052 return ret;
2053}
2054
2055static noinline int check_committed_ref(struct btrfs_trans_handle *trans,
2056 struct btrfs_root *root,
2057 struct btrfs_path *path,
2058 u64 objectid, u64 offset, u64 bytenr)
be20aa9d
CM		 2059{
2060 struct btrfs_root *extent_root = root->fs_info->extent_root;
f321e491 2061 struct extent_buffer *leaf;
5d4f98a2
YZ		 2062 struct btrfs_extent_data_ref *ref;
2063 struct btrfs_extent_inline_ref *iref;
2064 struct btrfs_extent_item *ei;
f321e491 2065 struct btrfs_key key;
5d4f98a2 2066 u32 item_size;
be20aa9d 2067 int ret;
925baedd 2068
be20aa9d 2069 key.objectid = bytenr;
31840ae1 2070 key.offset = (u64)-1;
f321e491 2071 key.type = BTRFS_EXTENT_ITEM_KEY;
be20aa9d 2072
be20aa9d
CM		 2073 ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
2074 if (ret < 0)
2075 goto out;
2076 BUG_ON(ret == 0);
80ff3856
YZ		 2077
2078 ret = -ENOENT;
2079 if (path->slots[0] == 0)
31840ae1 2080 goto out;
be20aa9d 2081
31840ae1 2082 path->slots[0]--;
f321e491 2083 leaf = path->nodes[0];
5d4f98a2 2084 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
be20aa9d 2085
5d4f98a2 2086 if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY)
be20aa9d 2087 goto out;
f321e491 2088
5d4f98a2
YZ		 2089 ret = 1;
2090 item_size = btrfs_item_size_nr(leaf, path->slots[0]);
2091#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
2092 if (item_size < sizeof(*ei)) {
2093 WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0));
2094 goto out;
2095 }
2096#endif
2097 ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
bd09835d 2098
5d4f98a2
YZ		 2099 if (item_size != sizeof(*ei) +
2100 btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY))
2101 goto out;
be20aa9d 2102
5d4f98a2
YZ		 2103 if (btrfs_extent_generation(leaf, ei) <=
2104 btrfs_root_last_snapshot(&root->root_item))
2105 goto out;
2106
2107 iref = (struct btrfs_extent_inline_ref *)(ei + 1);
2108 if (btrfs_extent_inline_ref_type(leaf, iref) !=
2109 BTRFS_EXTENT_DATA_REF_KEY)
2110 goto out;
2111
2112 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
2113 if (btrfs_extent_refs(leaf, ei) !=
2114 btrfs_extent_data_ref_count(leaf, ref) ||
2115 btrfs_extent_data_ref_root(leaf, ref) !=
2116 root->root_key.objectid ||
2117 btrfs_extent_data_ref_objectid(leaf, ref) != objectid ||
2118 btrfs_extent_data_ref_offset(leaf, ref) != offset)
2119 goto out;
2120
2121 ret = 0;
2122out:
2123 return ret;
2124}
2125
2126int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans,
2127 struct btrfs_root *root,
2128 u64 objectid, u64 offset, u64 bytenr)
2129{
2130 struct btrfs_path *path;
2131 int ret;
2132 int ret2;
2133
2134 path = btrfs_alloc_path();
2135 if (!path)
2136 return -ENOENT;
2137
2138 do {
2139 ret = check_committed_ref(trans, root, path, objectid,
2140 offset, bytenr);
2141 if (ret && ret != -ENOENT)
f321e491 2142 goto out;
80ff3856 2143
5d4f98a2
YZ		 2144 ret2 = check_delayed_ref(trans, root, path, objectid,
2145 offset, bytenr);
2146 } while (ret2 == -EAGAIN);
2147
2148 if (ret2 && ret2 != -ENOENT) {
2149 ret = ret2;
2150 goto out;
f321e491 2151 }
5d4f98a2
YZ		 2152
2153 if (ret != -ENOENT || ret2 != -ENOENT)
2154 ret = 0;
be20aa9d 2155out:
80ff3856 2156 btrfs_free_path(path);
f321e491 2157 return ret;
be20aa9d 2158}
c5739bba 2159
5d4f98a2 2160#if 0
31840ae1
ZY		 2161int btrfs_cache_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2162 struct extent_buffer *buf, u32 nr_extents)
02217ed2 2163{
5f39d397 2164 struct btrfs_key key;
6407bf6d 2165 struct btrfs_file_extent_item *fi;
e4657689
ZY		 2166 u64 root_gen;
2167 u32 nritems;
02217ed2 2168 int i;
db94535d 2169 int level;
31840ae1 2170 int ret = 0;
e4657689 2171 int shared = 0;
a28ec197 2172
3768f368 2173 if (!root->ref_cows)
a28ec197 2174 return 0;
5f39d397 2175
e4657689
ZY		 2176 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
2177 shared = 0;
2178 root_gen = root->root_key.offset;
2179 } else {
2180 shared = 1;
2181 root_gen = trans->transid - 1;
2182 }
2183
db94535d 2184 level = btrfs_header_level(buf);
5f39d397 2185 nritems = btrfs_header_nritems(buf);
4a096752 2186
31840ae1 2187 if (level == 0) {
31153d81
YZ		 2188 struct btrfs_leaf_ref *ref;
2189 struct btrfs_extent_info *info;
2190
31840ae1 2191 ref = btrfs_alloc_leaf_ref(root, nr_extents);
31153d81 2192 if (!ref) {
31840ae1 2193 ret = -ENOMEM;
31153d81
YZ		 2194 goto out;
2195 }
2196
e4657689 2197 ref->root_gen = root_gen;
31153d81
YZ		 2198 ref->bytenr = buf->start;
2199 ref->owner = btrfs_header_owner(buf);
2200 ref->generation = btrfs_header_generation(buf);
31840ae1 2201 ref->nritems = nr_extents;
31153d81 2202 info = ref->extents;
bcc63abb 2203
31840ae1 2204 for (i = 0; nr_extents > 0 && i < nritems; i++) {
31153d81
YZ		 2205 u64 disk_bytenr;
2206 btrfs_item_key_to_cpu(buf, &key, i);
2207 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2208 continue;
2209 fi = btrfs_item_ptr(buf, i,
2210 struct btrfs_file_extent_item);
2211 if (btrfs_file_extent_type(buf, fi) ==
2212 BTRFS_FILE_EXTENT_INLINE)
2213 continue;
2214 disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2215 if (disk_bytenr == 0)
2216 continue;
2217
2218 info->bytenr = disk_bytenr;
2219 info->num_bytes =
2220 btrfs_file_extent_disk_num_bytes(buf, fi);
2221 info->objectid = key.objectid;
2222 info->offset = key.offset;
2223 info++;
2224 }
2225
e4657689 2226 ret = btrfs_add_leaf_ref(root, ref, shared);
5b84e8d6
YZ		 2227 if (ret == -EEXIST && shared) {
2228 struct btrfs_leaf_ref *old;
2229 old = btrfs_lookup_leaf_ref(root, ref->bytenr);
2230 BUG_ON(!old);
2231 btrfs_remove_leaf_ref(root, old);
2232 btrfs_free_leaf_ref(root, old);
2233 ret = btrfs_add_leaf_ref(root, ref, shared);
2234 }
31153d81 2235 WARN_ON(ret);
bcc63abb 2236 btrfs_free_leaf_ref(root, ref);
31153d81
YZ		 2237 }
2238out:
31840ae1
ZY		 2239 return ret;
2240}
2241
b7a9f29f
CM		 2242/* when a block goes through cow, we update the reference counts of
2243 * everything that block points to. The internal pointers of the block
2244 * can be in just about any order, and it is likely to have clusters of
2245 * things that are close together and clusters of things that are not.
2246 *
2247 * To help reduce the seeks that come with updating all of these reference
2248 * counts, sort them by byte number before actual updates are done.
2249 *
2250 * struct refsort is used to match byte number to slot in the btree block.
2251 * we sort based on the byte number and then use the slot to actually
2252 * find the item.
bd56b302
CM		 2253 *
2254 * struct refsort is smaller than strcut btrfs_item and smaller than
2255 * struct btrfs_key_ptr. Since we're currently limited to the page size
2256 * for a btree block, there's no way for a kmalloc of refsorts for a
2257 * single node to be bigger than a page.
b7a9f29f
CM		 2258 */
2259struct refsort {
2260 u64 bytenr;
2261 u32 slot;
2262};
2263
2264/*
2265 * for passing into sort()
2266 */
2267static int refsort_cmp(const void *a_void, const void *b_void)
2268{
2269 const struct refsort *a = a_void;
2270 const struct refsort *b = b_void;
2271
2272 if (a->bytenr < b->bytenr)
2273 return -1;
2274 if (a->bytenr > b->bytenr)
2275 return 1;
2276 return 0;
2277}
5d4f98a2 2278#endif
b7a9f29f 2279
5d4f98a2 2280static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
b7a9f29f 2281 struct btrfs_root *root,
5d4f98a2
YZ		 2282 struct extent_buffer *buf,
2283 int full_backref, int inc)
31840ae1
ZY		 2284{
2285 u64 bytenr;
5d4f98a2
YZ		 2286 u64 num_bytes;
2287 u64 parent;
31840ae1 2288 u64 ref_root;
31840ae1 2289 u32 nritems;
31840ae1
ZY		 2290 struct btrfs_key key;
2291 struct btrfs_file_extent_item *fi;
2292 int i;
2293 int level;
2294 int ret = 0;
31840ae1 2295 int (*process_func)(struct btrfs_trans_handle *, struct btrfs_root *,
5d4f98a2 2296 u64, u64, u64, u64, u64, u64);
31840ae1
ZY		 2297
2298 ref_root = btrfs_header_owner(buf);
31840ae1
ZY		 2299 nritems = btrfs_header_nritems(buf);
2300 level = btrfs_header_level(buf);
2301
5d4f98a2
YZ		 2302 if (!root->ref_cows && level == 0)
2303 return 0;
31840ae1 2304
5d4f98a2
YZ		 2305 if (inc)
2306 process_func = btrfs_inc_extent_ref;
2307 else
2308 process_func = btrfs_free_extent;
31840ae1 2309
5d4f98a2
YZ		 2310 if (full_backref)
2311 parent = buf->start;
2312 else
2313 parent = 0;
2314
2315 for (i = 0; i < nritems; i++) {
31840ae1 2316 if (level == 0) {
5d4f98a2 2317 btrfs_item_key_to_cpu(buf, &key, i);
31840ae1
ZY		 2318 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
2319 continue;
5d4f98a2 2320 fi = btrfs_item_ptr(buf, i,
31840ae1
ZY		 2321 struct btrfs_file_extent_item);
2322 if (btrfs_file_extent_type(buf, fi) ==
2323 BTRFS_FILE_EXTENT_INLINE)
2324 continue;
2325 bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
2326 if (bytenr == 0)
2327 continue;
5d4f98a2
YZ		 2328
2329 num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
2330 key.offset -= btrfs_file_extent_offset(buf, fi);
2331 ret = process_func(trans, root, bytenr, num_bytes,
2332 parent, ref_root, key.objectid,
2333 key.offset);
31840ae1
ZY		 2334 if (ret)
2335 goto fail;
2336 } else {
5d4f98a2
YZ		 2337 bytenr = btrfs_node_blockptr(buf, i);
2338 num_bytes = btrfs_level_size(root, level - 1);
2339 ret = process_func(trans, root, bytenr, num_bytes,
2340 parent, ref_root, level - 1, 0);
31840ae1
ZY		 2341 if (ret)
2342 goto fail;
2343 }
2344 }
2345 return 0;
2346fail:
5d4f98a2
YZ		 2347 BUG();
2348 return ret;
2349}
2350
2351int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2352 struct extent_buffer *buf, int full_backref)
2353{
2354 return __btrfs_mod_ref(trans, root, buf, full_backref, 1);
2355}
2356
2357int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
2358 struct extent_buffer *buf, int full_backref)
2359{
2360 return __btrfs_mod_ref(trans, root, buf, full_backref, 0);
31840ae1
ZY		 2361}
2362
9078a3e1
CM		 2363static int write_one_cache_group(struct btrfs_trans_handle *trans,
2364 struct btrfs_root *root,
2365 struct btrfs_path *path,
2366 struct btrfs_block_group_cache *cache)
2367{
2368 int ret;
9078a3e1 2369 struct btrfs_root *extent_root = root->fs_info->extent_root;
5f39d397
CM		 2370 unsigned long bi;
2371 struct extent_buffer *leaf;
9078a3e1 2372
9078a3e1 2373 ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
54aa1f4d
CM		 2374 if (ret < 0)
2375 goto fail;
9078a3e1 2376 BUG_ON(ret);
5f39d397
CM		 2377
2378 leaf = path->nodes[0];
2379 bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
2380 write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
2381 btrfs_mark_buffer_dirty(leaf);
9078a3e1 2382 btrfs_release_path(extent_root, path);
54aa1f4d 2383fail:
9078a3e1
CM		 2384 if (ret)
2385 return ret;
9078a3e1
CM		 2386 return 0;
2387
2388}
2389
96b5179d
CM		 2390int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
2391 struct btrfs_root *root)
9078a3e1 2392{
0f9dd46c
JB		 2393 struct btrfs_block_group_cache *cache, *entry;
2394 struct rb_node *n;
9078a3e1
CM		 2395 int err = 0;
2396 int werr = 0;
9078a3e1 2397 struct btrfs_path *path;
96b5179d 2398 u64 last = 0;
9078a3e1
CM		 2399
2400 path = btrfs_alloc_path();
2401 if (!path)
2402 return -ENOMEM;
2403
d397712b 2404 while (1) {
0f9dd46c
JB		 2405 cache = NULL;
2406 spin_lock(&root->fs_info->block_group_cache_lock);
2407 for (n = rb_first(&root->fs_info->block_group_cache_tree);
2408 n; n = rb_next(n)) {
2409 entry = rb_entry(n, struct btrfs_block_group_cache,
2410 cache_node);
2411 if (entry->dirty) {
2412 cache = entry;
2413 break;
2414 }
2415 }
2416 spin_unlock(&root->fs_info->block_group_cache_lock);
54aa1f4d 2417
0f9dd46c 2418 if (!cache)
96b5179d 2419 break;
0f9dd46c 2420
e8569813 2421 cache->dirty = 0;
0f9dd46c
JB		 2422 last += cache->key.offset;
2423
96b5179d
CM		 2424 err = write_one_cache_group(trans, root,
2425 path, cache);
2426 /*
2427 * if we fail to write the cache group, we want
2428 * to keep it marked dirty in hopes that a later
2429 * write will work
2430 */
2431 if (err) {
2432 werr = err;
2433 continue;
9078a3e1
CM		 2434 }
2435 }
2436 btrfs_free_path(path);
2437 return werr;
2438}
2439
d2fb3437
YZ		 2440int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr)
2441{
2442 struct btrfs_block_group_cache *block_group;
2443 int readonly = 0;
2444
2445 block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
2446 if (!block_group || block_group->ro)
2447 readonly = 1;
2448 if (block_group)
fa9c0d79 2449 btrfs_put_block_group(block_group);
d2fb3437
YZ		 2450 return readonly;
2451}
2452
593060d7
CM		 2453static int update_space_info(struct btrfs_fs_info *info, u64 flags,
2454 u64 total_bytes, u64 bytes_used,
2455 struct btrfs_space_info **space_info)
2456{
2457 struct btrfs_space_info *found;
2458
2459 found = __find_space_info(info, flags);
2460 if (found) {
25179201 2461 spin_lock(&found->lock);
593060d7
CM		 2462 found->total_bytes += total_bytes;
2463 found->bytes_used += bytes_used;
8f18cf13 2464 found->full = 0;
25179201 2465 spin_unlock(&found->lock);
593060d7
CM		 2466 *space_info = found;
2467 return 0;
2468 }
c146afad 2469 found = kzalloc(sizeof(*found), GFP_NOFS);
593060d7
CM		 2470 if (!found)
2471 return -ENOMEM;
2472
0f9dd46c 2473 INIT_LIST_HEAD(&found->block_groups);
80eb234a 2474 init_rwsem(&found->groups_sem);
0f9dd46c 2475 spin_lock_init(&found->lock);
593060d7
CM		 2476 found->flags = flags;
2477 found->total_bytes = total_bytes;
2478 found->bytes_used = bytes_used;
2479 found->bytes_pinned = 0;
e8569813 2480 found->bytes_reserved = 0;
c146afad 2481 found->bytes_readonly = 0;
6a63209f 2482 found->bytes_delalloc = 0;
593060d7 2483 found->full = 0;
0ef3e66b 2484 found->force_alloc = 0;
593060d7 2485 *space_info = found;
4184ea7f 2486 list_add_rcu(&found->list, &info->space_info);
593060d7
CM		 2487 return 0;
2488}
2489
8790d502
CM		 2490static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
2491{
2492 u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 |
611f0e00 2493 BTRFS_BLOCK_GROUP_RAID1 |
321aecc6 2494 BTRFS_BLOCK_GROUP_RAID10 |
611f0e00 2495 BTRFS_BLOCK_GROUP_DUP);
8790d502
CM		 2496 if (extra_flags) {
2497 if (flags & BTRFS_BLOCK_GROUP_DATA)
2498 fs_info->avail_data_alloc_bits |= extra_flags;
2499 if (flags & BTRFS_BLOCK_GROUP_METADATA)
2500 fs_info->avail_metadata_alloc_bits |= extra_flags;
2501 if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
2502 fs_info->avail_system_alloc_bits |= extra_flags;
2503 }
2504}
593060d7 2505
c146afad
YZ		 2506static void set_block_group_readonly(struct btrfs_block_group_cache *cache)
2507{
2508 spin_lock(&cache->space_info->lock);
2509 spin_lock(&cache->lock);
2510 if (!cache->ro) {
2511 cache->space_info->bytes_readonly += cache->key.offset -
2512 btrfs_block_group_used(&cache->item);
2513 cache->ro = 1;
2514 }
2515 spin_unlock(&cache->lock);
2516 spin_unlock(&cache->space_info->lock);
2517}
2518
2b82032c 2519u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
ec44a35c 2520{
2b82032c 2521 u64 num_devices = root->fs_info->fs_devices->rw_devices;
a061fc8d
CM		 2522
2523 if (num_devices == 1)
2524 flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0);
2525 if (num_devices < 4)
2526 flags &= ~BTRFS_BLOCK_GROUP_RAID10;
2527
ec44a35c
CM		 2528 if ((flags & BTRFS_BLOCK_GROUP_DUP) &&
2529 (flags & (BTRFS_BLOCK_GROUP_RAID1 |
a061fc8d 2530 BTRFS_BLOCK_GROUP_RAID10))) {
ec44a35c 2531 flags &= ~BTRFS_BLOCK_GROUP_DUP;
a061fc8d 2532 }
ec44a35c
CM		 2533
2534 if ((flags & BTRFS_BLOCK_GROUP_RAID1) &&
a061fc8d 2535 (flags & BTRFS_BLOCK_GROUP_RAID10)) {
ec44a35c 2536 flags &= ~BTRFS_BLOCK_GROUP_RAID1;
a061fc8d 2537 }
ec44a35c
CM		 2538
2539 if ((flags & BTRFS_BLOCK_GROUP_RAID0) &&
2540 ((flags & BTRFS_BLOCK_GROUP_RAID1) |
2541 (flags & BTRFS_BLOCK_GROUP_RAID10) |
2542 (flags & BTRFS_BLOCK_GROUP_DUP)))
2543 flags &= ~BTRFS_BLOCK_GROUP_RAID0;
2544 return flags;
2545}
2546
6a63209f
JB		 2547static u64 btrfs_get_alloc_profile(struct btrfs_root *root, u64 data)
2548{
2549 struct btrfs_fs_info *info = root->fs_info;
2550 u64 alloc_profile;
2551
2552 if (data) {
2553 alloc_profile = info->avail_data_alloc_bits &
2554 info->data_alloc_profile;
2555 data = BTRFS_BLOCK_GROUP_DATA | alloc_profile;
2556 } else if (root == root->fs_info->chunk_root) {
2557 alloc_profile = info->avail_system_alloc_bits &
2558 info->system_alloc_profile;
2559 data = BTRFS_BLOCK_GROUP_SYSTEM | alloc_profile;
2560 } else {
2561 alloc_profile = info->avail_metadata_alloc_bits &
2562 info->metadata_alloc_profile;
2563 data = BTRFS_BLOCK_GROUP_METADATA | alloc_profile;
2564 }
2565
2566 return btrfs_reduce_alloc_profile(root, data);
2567}
2568
2569void btrfs_set_inode_space_info(struct btrfs_root *root, struct inode *inode)
2570{
2571 u64 alloc_target;
2572
2573 alloc_target = btrfs_get_alloc_profile(root, 1);
2574 BTRFS_I(inode)->space_info = __find_space_info(root->fs_info,
2575 alloc_target);
2576}
2577
2578/*
2579 * for now this just makes sure we have at least 5% of our metadata space free
2580 * for use.
2581 */
2582int btrfs_check_metadata_free_space(struct btrfs_root *root)
2583{
2584 struct btrfs_fs_info *info = root->fs_info;
2585 struct btrfs_space_info *meta_sinfo;
2586 u64 alloc_target, thresh;
4e06bdd6 2587 int committed = 0, ret;
6a63209f
JB		 2588
2589 /* get the space info for where the metadata will live */
2590 alloc_target = btrfs_get_alloc_profile(root, 0);
2591 meta_sinfo = __find_space_info(info, alloc_target);
2592
4e06bdd6 2593again:
6a63209f 2594 spin_lock(&meta_sinfo->lock);
4e06bdd6
JB		 2595 if (!meta_sinfo->full)
2596 thresh = meta_sinfo->total_bytes * 80;
2597 else
2598 thresh = meta_sinfo->total_bytes * 95;
6a63209f
JB		 2599
2600 do_div(thresh, 100);
2601
2602 if (meta_sinfo->bytes_used + meta_sinfo->bytes_reserved +
2603 meta_sinfo->bytes_pinned + meta_sinfo->bytes_readonly > thresh) {
4e06bdd6
JB		 2604 struct btrfs_trans_handle *trans;
2605 if (!meta_sinfo->full) {
2606 meta_sinfo->force_alloc = 1;
2607 spin_unlock(&meta_sinfo->lock);
2608
2609 trans = btrfs_start_transaction(root, 1);
2610 if (!trans)
2611 return -ENOMEM;
2612
2613 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
2614 2 * 1024 * 1024, alloc_target, 0);
2615 btrfs_end_transaction(trans, root);
2616 goto again;
2617 }
6a63209f 2618 spin_unlock(&meta_sinfo->lock);
4e06bdd6
JB		 2619
2620 if (!committed) {
2621 committed = 1;
2622 trans = btrfs_join_transaction(root, 1);
2623 if (!trans)
2624 return -ENOMEM;
2625 ret = btrfs_commit_transaction(trans, root);
2626 if (ret)
2627 return ret;
2628 goto again;
2629 }
6a63209f
JB		 2630 return -ENOSPC;
2631 }
2632 spin_unlock(&meta_sinfo->lock);
2633
2634 return 0;
2635}
2636
2637/*
2638 * This will check the space that the inode allocates from to make sure we have
2639 * enough space for bytes.
2640 */
2641int btrfs_check_data_free_space(struct btrfs_root *root, struct inode *inode,
2642 u64 bytes)
2643{
2644 struct btrfs_space_info *data_sinfo;
4e06bdd6 2645 int ret = 0, committed = 0;
6a63209f
JB		 2646
2647 /* make sure bytes are sectorsize aligned */
2648 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
2649
2650 data_sinfo = BTRFS_I(inode)->space_info;
2651again:
2652 /* make sure we have enough space to handle the data first */
2653 spin_lock(&data_sinfo->lock);
2654 if (data_sinfo->total_bytes - data_sinfo->bytes_used -
2655 data_sinfo->bytes_delalloc - data_sinfo->bytes_reserved -
2656 data_sinfo->bytes_pinned - data_sinfo->bytes_readonly -
2657 data_sinfo->bytes_may_use < bytes) {
4e06bdd6
JB		 2658 struct btrfs_trans_handle *trans;
2659
6a63209f
JB		 2660 /*
2661 * if we don't have enough free bytes in this space then we need
2662 * to alloc a new chunk.
2663 */
2664 if (!data_sinfo->full) {
2665 u64 alloc_target;
6a63209f
JB		 2666
2667 data_sinfo->force_alloc = 1;
2668 spin_unlock(&data_sinfo->lock);
2669
2670 alloc_target = btrfs_get_alloc_profile(root, 1);
2671 trans = btrfs_start_transaction(root, 1);
2672 if (!trans)
2673 return -ENOMEM;
2674
2675 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
2676 bytes + 2 * 1024 * 1024,
2677 alloc_target, 0);
2678 btrfs_end_transaction(trans, root);
2679 if (ret)
2680 return ret;
2681 goto again;
2682 }
2683 spin_unlock(&data_sinfo->lock);
4e06bdd6
JB		 2684
2685 /* commit the current transaction and try again */
2686 if (!committed) {
2687 committed = 1;
2688 trans = btrfs_join_transaction(root, 1);
2689 if (!trans)
2690 return -ENOMEM;
2691 ret = btrfs_commit_transaction(trans, root);
2692 if (ret)
2693 return ret;
2694 goto again;
2695 }
2696
6a63209f
JB		 2697 printk(KERN_ERR "no space left, need %llu, %llu delalloc bytes"
2698 ", %llu bytes_used, %llu bytes_reserved, "
68f5a38c 2699 "%llu bytes_pinned, %llu bytes_readonly, %llu may use "
21380931
JB		 2700 "%llu total\n", (unsigned long long)bytes,
2701 (unsigned long long)data_sinfo->bytes_delalloc,
2702 (unsigned long long)data_sinfo->bytes_used,
2703 (unsigned long long)data_sinfo->bytes_reserved,
2704 (unsigned long long)data_sinfo->bytes_pinned,
2705 (unsigned long long)data_sinfo->bytes_readonly,
2706 (unsigned long long)data_sinfo->bytes_may_use,
2707 (unsigned long long)data_sinfo->total_bytes);
6a63209f
JB		 2708 return -ENOSPC;
2709 }
2710 data_sinfo->bytes_may_use += bytes;
2711 BTRFS_I(inode)->reserved_bytes += bytes;
2712 spin_unlock(&data_sinfo->lock);
2713
2714 return btrfs_check_metadata_free_space(root);
2715}
2716
2717/*
2718 * if there was an error for whatever reason after calling
2719 * btrfs_check_data_free_space, call this so we can cleanup the counters.
2720 */
2721void btrfs_free_reserved_data_space(struct btrfs_root *root,
2722 struct inode *inode, u64 bytes)
2723{
2724 struct btrfs_space_info *data_sinfo;
2725
2726 /* make sure bytes are sectorsize aligned */
2727 bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
2728
2729 data_sinfo = BTRFS_I(inode)->space_info;
2730 spin_lock(&data_sinfo->lock);
2731 data_sinfo->bytes_may_use -= bytes;
2732 BTRFS_I(inode)->reserved_bytes -= bytes;
2733 spin_unlock(&data_sinfo->lock);
2734}
2735
2736/* called when we are adding a delalloc extent to the inode's io_tree */
2737void btrfs_delalloc_reserve_space(struct btrfs_root *root, struct inode *inode,
2738 u64 bytes)
2739{
2740 struct btrfs_space_info *data_sinfo;
2741
2742 /* get the space info for where this inode will be storing its data */
2743 data_sinfo = BTRFS_I(inode)->space_info;
2744
2745 /* make sure we have enough space to handle the data first */
2746 spin_lock(&data_sinfo->lock);
2747 data_sinfo->bytes_delalloc += bytes;
2748
2749 /*
2750 * we are adding a delalloc extent without calling
2751 * btrfs_check_data_free_space first. This happens on a weird
2752 * writepage condition, but shouldn't hurt our accounting
2753 */
2754 if (unlikely(bytes > BTRFS_I(inode)->reserved_bytes)) {
2755 data_sinfo->bytes_may_use -= BTRFS_I(inode)->reserved_bytes;
2756 BTRFS_I(inode)->reserved_bytes = 0;
2757 } else {
2758 data_sinfo->bytes_may_use -= bytes;
2759 BTRFS_I(inode)->reserved_bytes -= bytes;
2760 }
2761
2762 spin_unlock(&data_sinfo->lock);
2763}
2764
2765/* called when we are clearing an delalloc extent from the inode's io_tree */
2766void btrfs_delalloc_free_space(struct btrfs_root *root, struct inode *inode,
2767 u64 bytes)
2768{
2769 struct btrfs_space_info *info;
2770
2771 info = BTRFS_I(inode)->space_info;
2772
2773 spin_lock(&info->lock);
2774 info->bytes_delalloc -= bytes;
2775 spin_unlock(&info->lock);
2776}
2777
97e728d4
JB		 2778static void force_metadata_allocation(struct btrfs_fs_info *info)
2779{
2780 struct list_head *head = &info->space_info;
2781 struct btrfs_space_info *found;
2782
2783 rcu_read_lock();
2784 list_for_each_entry_rcu(found, head, list) {
2785 if (found->flags & BTRFS_BLOCK_GROUP_METADATA)
2786 found->force_alloc = 1;
2787 }
2788 rcu_read_unlock();
2789}
2790
6324fbf3
CM		 2791static int do_chunk_alloc(struct btrfs_trans_handle *trans,
2792 struct btrfs_root *extent_root, u64 alloc_bytes,
0ef3e66b 2793 u64 flags, int force)
6324fbf3
CM		 2794{
2795 struct btrfs_space_info *space_info;
97e728d4 2796 struct btrfs_fs_info *fs_info = extent_root->fs_info;
6324fbf3 2797 u64 thresh;
c146afad
YZ		 2798 int ret = 0;
2799
97e728d4 2800 mutex_lock(&fs_info->chunk_mutex);
6324fbf3 2801
2b82032c 2802 flags = btrfs_reduce_alloc_profile(extent_root, flags);
ec44a35c 2803
6324fbf3 2804 space_info = __find_space_info(extent_root->fs_info, flags);
593060d7
CM		 2805 if (!space_info) {
2806 ret = update_space_info(extent_root->fs_info, flags,
2807 0, 0, &space_info);
2808 BUG_ON(ret);
2809 }
6324fbf3
CM		 2810 BUG_ON(!space_info);
2811
25179201 2812 spin_lock(&space_info->lock);
0ef3e66b
CM		 2813 if (space_info->force_alloc) {
2814 force = 1;
2815 space_info->force_alloc = 0;
2816 }
25179201
JB		 2817 if (space_info->full) {
2818 spin_unlock(&space_info->lock);
925baedd 2819 goto out;
25179201 2820 }
6324fbf3 2821
c146afad
YZ		 2822 thresh = space_info->total_bytes - space_info->bytes_readonly;
2823 thresh = div_factor(thresh, 6);
0ef3e66b 2824 if (!force &&
e8569813 2825 (space_info->bytes_used + space_info->bytes_pinned +
25179201
JB		 2826 space_info->bytes_reserved + alloc_bytes) < thresh) {
2827 spin_unlock(&space_info->lock);
925baedd 2828 goto out;
25179201 2829 }
25179201
JB		 2830 spin_unlock(&space_info->lock);
2831
97e728d4
JB		 2832 /*
2833 * if we're doing a data chunk, go ahead and make sure that
2834 * we keep a reasonable number of metadata chunks allocated in the
2835 * FS as well.
2836 */
2837 if (flags & BTRFS_BLOCK_GROUP_DATA) {
2838 fs_info->data_chunk_allocations++;
2839 if (!(fs_info->data_chunk_allocations %
2840 fs_info->metadata_ratio))
2841 force_metadata_allocation(fs_info);
2842 }
2843
2b82032c 2844 ret = btrfs_alloc_chunk(trans, extent_root, flags);
d397712b 2845 if (ret)
6324fbf3 2846 space_info->full = 1;
a74a4b97 2847out:
c146afad 2848 mutex_unlock(&extent_root->fs_info->chunk_mutex);
0f9dd46c 2849 return ret;
6324fbf3
CM		 2850}
2851
9078a3e1
CM		 2852static int update_block_group(struct btrfs_trans_handle *trans,
2853 struct btrfs_root *root,
db94535d 2854 u64 bytenr, u64 num_bytes, int alloc,
0b86a832 2855 int mark_free)
9078a3e1
CM		 2856{
2857 struct btrfs_block_group_cache *cache;
2858 struct btrfs_fs_info *info = root->fs_info;
db94535d 2859 u64 total = num_bytes;
9078a3e1 2860 u64 old_val;
db94535d 2861 u64 byte_in_group;
3e1ad54f 2862
5d4f98a2
YZ		 2863 /* block accounting for super block */
2864 spin_lock(&info->delalloc_lock);
2865 old_val = btrfs_super_bytes_used(&info->super_copy);
2866 if (alloc)
2867 old_val += num_bytes;
2868 else
2869 old_val -= num_bytes;
2870 btrfs_set_super_bytes_used(&info->super_copy, old_val);
2871
2872 /* block accounting for root item */
2873 old_val = btrfs_root_used(&root->root_item);
2874 if (alloc)
2875 old_val += num_bytes;
2876 else
2877 old_val -= num_bytes;
2878 btrfs_set_root_used(&root->root_item, old_val);
2879 spin_unlock(&info->delalloc_lock);
2880
d397712b 2881 while (total) {
db94535d 2882 cache = btrfs_lookup_block_group(info, bytenr);
f3465ca4 2883 if (!cache)
9078a3e1 2884 return -1;
db94535d
CM		 2885 byte_in_group = bytenr - cache->key.objectid;
2886 WARN_ON(byte_in_group > cache->key.offset);
9078a3e1 2887
25179201 2888 spin_lock(&cache->space_info->lock);
c286ac48 2889 spin_lock(&cache->lock);
0f9dd46c 2890 cache->dirty = 1;
9078a3e1 2891 old_val = btrfs_block_group_used(&cache->item);
db94535d 2892 num_bytes = min(total, cache->key.offset - byte_in_group);
cd1bc465 2893 if (alloc) {
db94535d 2894 old_val += num_bytes;
6324fbf3 2895 cache->space_info->bytes_used += num_bytes;
a512bbf8 2896 if (cache->ro)
c146afad 2897 cache->space_info->bytes_readonly -= num_bytes;
c286ac48
CM		 2898 btrfs_set_block_group_used(&cache->item, old_val);
2899 spin_unlock(&cache->lock);
25179201 2900 spin_unlock(&cache->space_info->lock);
cd1bc465 2901 } else {
db94535d 2902 old_val -= num_bytes;
6324fbf3 2903 cache->space_info->bytes_used -= num_bytes;
c146afad
YZ		 2904 if (cache->ro)
2905 cache->space_info->bytes_readonly += num_bytes;
c286ac48
CM		 2906 btrfs_set_block_group_used(&cache->item, old_val);
2907 spin_unlock(&cache->lock);
25179201 2908 spin_unlock(&cache->space_info->lock);
f510cfec 2909 if (mark_free) {
0f9dd46c 2910 int ret;
1f3c79a2
LH		 2911
2912 ret = btrfs_discard_extent(root, bytenr,
2913 num_bytes);
2914 WARN_ON(ret);
2915
0f9dd46c
JB		 2916 ret = btrfs_add_free_space(cache, bytenr,
2917 num_bytes);
d2fb3437 2918 WARN_ON(ret);
e37c9e69 2919 }
cd1bc465 2920 }
fa9c0d79 2921 btrfs_put_block_group(cache);
db94535d
CM		 2922 total -= num_bytes;
2923 bytenr += num_bytes;
9078a3e1
CM		 2924 }
2925 return 0;
2926}
6324fbf3 2927
a061fc8d
CM		 2928static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
2929{
0f9dd46c 2930 struct btrfs_block_group_cache *cache;
d2fb3437 2931 u64 bytenr;
0f9dd46c
JB		 2932
2933 cache = btrfs_lookup_first_block_group(root->fs_info, search_start);
2934 if (!cache)
a061fc8d 2935 return 0;
0f9dd46c 2936
d2fb3437 2937 bytenr = cache->key.objectid;
fa9c0d79 2938 btrfs_put_block_group(cache);
d2fb3437
YZ		 2939
2940 return bytenr;
a061fc8d
CM		 2941}
2942
e02119d5 2943int btrfs_update_pinned_extents(struct btrfs_root *root,
324ae4df
Y		 2944 u64 bytenr, u64 num, int pin)
2945{
2946 u64 len;
2947 struct btrfs_block_group_cache *cache;
2948 struct btrfs_fs_info *fs_info = root->fs_info;
2949
2950 if (pin) {
2951 set_extent_dirty(&fs_info->pinned_extents,
2952 bytenr, bytenr + num - 1, GFP_NOFS);
2953 } else {
2954 clear_extent_dirty(&fs_info->pinned_extents,
2955 bytenr, bytenr + num - 1, GFP_NOFS);
2956 }
b9473439 2957
324ae4df
Y		 2958 while (num > 0) {
2959 cache = btrfs_lookup_block_group(fs_info, bytenr);
e8569813
ZY		 2960 BUG_ON(!cache);
2961 len = min(num, cache->key.offset -
2962 (bytenr - cache->key.objectid));
324ae4df 2963 if (pin) {
25179201 2964 spin_lock(&cache->space_info->lock);
e8569813
ZY		 2965 spin_lock(&cache->lock);
2966 cache->pinned += len;
2967 cache->space_info->bytes_pinned += len;
2968 spin_unlock(&cache->lock);
25179201 2969 spin_unlock(&cache->space_info->lock);
324ae4df
Y		 2970 fs_info->total_pinned += len;
2971 } else {
25179201 2972 spin_lock(&cache->space_info->lock);
e8569813
ZY		 2973 spin_lock(&cache->lock);
2974 cache->pinned -= len;
2975 cache->space_info->bytes_pinned -= len;
2976 spin_unlock(&cache->lock);
25179201 2977 spin_unlock(&cache->space_info->lock);
324ae4df 2978 fs_info->total_pinned -= len;
07103a3c
JB		 2979 if (cache->cached)
2980 btrfs_add_free_space(cache, bytenr, len);
324ae4df 2981 }
fa9c0d79 2982 btrfs_put_block_group(cache);
324ae4df
Y		 2983 bytenr += len;
2984 num -= len;
2985 }
2986 return 0;
2987}
9078a3e1 2988
e8569813
ZY		 2989static int update_reserved_extents(struct btrfs_root *root,
2990 u64 bytenr, u64 num, int reserve)
2991{
2992 u64 len;
2993 struct btrfs_block_group_cache *cache;
2994 struct btrfs_fs_info *fs_info = root->fs_info;
2995
e8569813
ZY		 2996 while (num > 0) {
2997 cache = btrfs_lookup_block_group(fs_info, bytenr);
2998 BUG_ON(!cache);
2999 len = min(num, cache->key.offset -
3000 (bytenr - cache->key.objectid));
25179201
JB		 3001
3002 spin_lock(&cache->space_info->lock);
3003 spin_lock(&cache->lock);
e8569813 3004 if (reserve) {
e8569813
ZY		 3005 cache->reserved += len;
3006 cache->space_info->bytes_reserved += len;
e8569813 3007 } else {
e8569813
ZY		 3008 cache->reserved -= len;
3009 cache->space_info->bytes_reserved -= len;
e8569813 3010 }
25179201
JB		 3011 spin_unlock(&cache->lock);
3012 spin_unlock(&cache->space_info->lock);
fa9c0d79 3013 btrfs_put_block_group(cache);
e8569813
ZY		 3014 bytenr += len;
3015 num -= len;
3016 }
3017 return 0;
3018}
3019
d1310b2e 3020int btrfs_copy_pinned(struct btrfs_root *root, struct extent_io_tree *copy)
ccd467d6 3021{
ccd467d6 3022 u64 last = 0;
1a5bc167
CM		 3023 u64 start;
3024 u64 end;
d1310b2e 3025 struct extent_io_tree *pinned_extents = &root->fs_info->pinned_extents;
ccd467d6 3026 int ret;
ccd467d6 3027
d397712b 3028 while (1) {
1a5bc167
CM		 3029 ret = find_first_extent_bit(pinned_extents, last,
3030 &start, &end, EXTENT_DIRTY);
3031 if (ret)
ccd467d6 3032 break;
1a5bc167
CM		 3033 set_extent_dirty(copy, start, end, GFP_NOFS);
3034 last = end + 1;
ccd467d6
CM		 3035 }
3036 return 0;
3037}
3038
3039int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
3040 struct btrfs_root *root,
d1310b2e 3041 struct extent_io_tree *unpin)
a28ec197 3042{
1a5bc167
CM		 3043 u64 start;
3044 u64 end;
a28ec197 3045 int ret;
a28ec197 3046
d397712b 3047 while (1) {
1a5bc167
CM		 3048 ret = find_first_extent_bit(unpin, 0, &start, &end,
3049 EXTENT_DIRTY);
3050 if (ret)
a28ec197 3051 break;
1f3c79a2
LH		 3052
3053 ret = btrfs_discard_extent(root, start, end + 1 - start);
3054
b9473439 3055 /* unlocks the pinned mutex */
e02119d5 3056 btrfs_update_pinned_extents(root, start, end + 1 - start, 0);
1a5bc167 3057 clear_extent_dirty(unpin, start, end, GFP_NOFS);
1f3c79a2 3058
b9473439 3059 cond_resched();
a28ec197 3060 }
1f3c79a2 3061 return ret;
a28ec197
CM		 3062}
3063
31840ae1
ZY		 3064static int pin_down_bytes(struct btrfs_trans_handle *trans,
3065 struct btrfs_root *root,
b9473439
CM		 3066 struct btrfs_path *path,
3067 u64 bytenr, u64 num_bytes, int is_data,
3068 struct extent_buffer **must_clean)
e20d96d6 3069{
1a5bc167 3070 int err = 0;
31840ae1 3071 struct extent_buffer *buf;
8ef97622 3072
31840ae1
ZY		 3073 if (is_data)
3074 goto pinit;
3075
3076 buf = btrfs_find_tree_block(root, bytenr, num_bytes);
3077 if (!buf)
3078 goto pinit;
3079
3080 /* we can reuse a block if it hasn't been written
3081 * and it is from this transaction. We can't
3082 * reuse anything from the tree log root because
3083 * it has tiny sub-transactions.
3084 */
3085 if (btrfs_buffer_uptodate(buf, 0) &&
3086 btrfs_try_tree_lock(buf)) {
3087 u64 header_owner = btrfs_header_owner(buf);
3088 u64 header_transid = btrfs_header_generation(buf);
3089 if (header_owner != BTRFS_TREE_LOG_OBJECTID &&
3090 header_transid == trans->transid &&
3091 !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
b9473439 3092 *must_clean = buf;
31840ae1 3093 return 1;
8ef97622 3094 }
31840ae1 3095 btrfs_tree_unlock(buf);
f4b9aa8d 3096 }
31840ae1
ZY		 3097 free_extent_buffer(buf);
3098pinit:
b9473439 3099 btrfs_set_path_blocking(path);
b9473439 3100 /* unlocks the pinned mutex */
31840ae1
ZY		 3101 btrfs_update_pinned_extents(root, bytenr, num_bytes, 1);
3102
be744175 3103 BUG_ON(err < 0);
e20d96d6
CM		 3104 return 0;
3105}
3106
5d4f98a2
YZ		 3107
3108static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
3109 struct btrfs_root *root,
3110 u64 bytenr, u64 num_bytes, u64 parent,
3111 u64 root_objectid, u64 owner_objectid,
3112 u64 owner_offset, int refs_to_drop,
3113 struct btrfs_delayed_extent_op *extent_op)
a28ec197 3114{
e2fa7227 3115 struct btrfs_key key;
5d4f98a2 3116 struct btrfs_path *path;
1261ec42
CM		 3117 struct btrfs_fs_info *info = root->fs_info;
3118 struct btrfs_root *extent_root = info->extent_root;
5f39d397 3119 struct extent_buffer *leaf;
5d4f98a2
YZ		 3120 struct btrfs_extent_item *ei;
3121 struct btrfs_extent_inline_ref *iref;
a28ec197 3122 int ret;
5d4f98a2 3123 int is_data;
952fccac
CM		 3124 int extent_slot = 0;
3125 int found_extent = 0;
3126 int num_to_del = 1;
5d4f98a2
YZ		 3127 u32 item_size;
3128 u64 refs;
037e6390 3129
5caf2a00 3130 path = btrfs_alloc_path();
54aa1f4d
CM		 3131 if (!path)
3132 return -ENOMEM;
5f26f772 3133
3c12ac72 3134 path->reada = 1;
b9473439 3135 path->leave_spinning = 1;
5d4f98a2
YZ		 3136
3137 is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
3138 BUG_ON(!is_data && refs_to_drop != 1);
3139
3140 ret = lookup_extent_backref(trans, extent_root, path, &iref,
3141 bytenr, num_bytes, parent,
3142 root_objectid, owner_objectid,
3143 owner_offset);
7bb86316 3144 if (ret == 0) {
952fccac 3145 extent_slot = path->slots[0];
5d4f98a2
YZ		 3146 while (extent_slot >= 0) {
3147 btrfs_item_key_to_cpu(path->nodes[0], &key,
952fccac 3148 extent_slot);
5d4f98a2 3149 if (key.objectid != bytenr)
952fccac 3150 break;
5d4f98a2
YZ		 3151 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
3152 key.offset == num_bytes) {
952fccac
CM		 3153 found_extent = 1;
3154 break;
3155 }
3156 if (path->slots[0] - extent_slot > 5)
3157 break;
5d4f98a2 3158 extent_slot--;
952fccac 3159 }
5d4f98a2
YZ		 3160#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
3161 item_size = btrfs_item_size_nr(path->nodes[0], extent_slot);
3162 if (found_extent && item_size < sizeof(*ei))
3163 found_extent = 0;
3164#endif
31840ae1 3165 if (!found_extent) {
5d4f98a2 3166 BUG_ON(iref);
56bec294 3167 ret = remove_extent_backref(trans, extent_root, path,
5d4f98a2
YZ		 3168 NULL, refs_to_drop,
3169 is_data);
31840ae1
ZY		 3170 BUG_ON(ret);
3171 btrfs_release_path(extent_root, path);
b9473439 3172 path->leave_spinning = 1;
5d4f98a2
YZ		 3173
3174 key.objectid = bytenr;
3175 key.type = BTRFS_EXTENT_ITEM_KEY;
3176 key.offset = num_bytes;
3177
31840ae1
ZY		 3178 ret = btrfs_search_slot(trans, extent_root,
3179 &key, path, -1, 1);
f3465ca4
JB		 3180 if (ret) {
3181 printk(KERN_ERR "umm, got %d back from search"
d397712b
CM		 3182 ", was looking for %llu\n", ret,
3183 (unsigned long long)bytenr);
f3465ca4
JB		 3184 btrfs_print_leaf(extent_root, path->nodes[0]);
3185 }
31840ae1
ZY		 3186 BUG_ON(ret);
3187 extent_slot = path->slots[0];
3188 }
7bb86316
CM		 3189 } else {
3190 btrfs_print_leaf(extent_root, path->nodes[0]);
3191 WARN_ON(1);
d397712b 3192 printk(KERN_ERR "btrfs unable to find ref byte nr %llu "
5d4f98a2 3193 "parent %llu root %llu owner %llu offset %llu\n",
d397712b 3194 (unsigned long long)bytenr,
56bec294 3195 (unsigned long long)parent,
d397712b 3196 (unsigned long long)root_objectid,
5d4f98a2
YZ		 3197 (unsigned long long)owner_objectid,
3198 (unsigned long long)owner_offset);
7bb86316 3199 }
5f39d397
CM		 3200
3201 leaf = path->nodes[0];
5d4f98a2
YZ		 3202 item_size = btrfs_item_size_nr(leaf, extent_slot);
3203#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
3204 if (item_size < sizeof(*ei)) {
3205 BUG_ON(found_extent || extent_slot != path->slots[0]);
3206 ret = convert_extent_item_v0(trans, extent_root, path,
3207 owner_objectid, 0);
3208 BUG_ON(ret < 0);
3209
3210 btrfs_release_path(extent_root, path);
3211 path->leave_spinning = 1;
3212
3213 key.objectid = bytenr;
3214 key.type = BTRFS_EXTENT_ITEM_KEY;
3215 key.offset = num_bytes;
3216
3217 ret = btrfs_search_slot(trans, extent_root, &key, path,
3218 -1, 1);
3219 if (ret) {
3220 printk(KERN_ERR "umm, got %d back from search"
3221 ", was looking for %llu\n", ret,
3222 (unsigned long long)bytenr);
3223 btrfs_print_leaf(extent_root, path->nodes[0]);
3224 }
3225 BUG_ON(ret);
3226 extent_slot = path->slots[0];
3227 leaf = path->nodes[0];
3228 item_size = btrfs_item_size_nr(leaf, extent_slot);
3229 }
3230#endif
3231 BUG_ON(item_size < sizeof(*ei));
952fccac 3232 ei = btrfs_item_ptr(leaf, extent_slot,
123abc88 3233 struct btrfs_extent_item);
5d4f98a2
YZ		 3234 if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID) {
3235 struct btrfs_tree_block_info *bi;
3236 BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
3237 bi = (struct btrfs_tree_block_info *)(ei + 1);
3238 WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
3239 }
56bec294 3240
5d4f98a2 3241 refs = btrfs_extent_refs(leaf, ei);
56bec294
CM		 3242 BUG_ON(refs < refs_to_drop);
3243 refs -= refs_to_drop;
5f39d397 3244
5d4f98a2
YZ		 3245 if (refs > 0) {
3246 if (extent_op)
3247 __run_delayed_extent_op(extent_op, leaf, ei);
3248 /*
3249 * In the case of inline back ref, reference count will
3250 * be updated by remove_extent_backref
952fccac 3251 */
5d4f98a2
YZ		 3252 if (iref) {
3253 BUG_ON(!found_extent);
3254 } else {
3255 btrfs_set_extent_refs(leaf, ei, refs);
3256 btrfs_mark_buffer_dirty(leaf);
3257 }
3258 if (found_extent) {
3259 ret = remove_extent_backref(trans, extent_root, path,
3260 iref, refs_to_drop,
3261 is_data);
952fccac
CM		 3262 BUG_ON(ret);
3263 }
5d4f98a2
YZ		 3264 } else {
3265 int mark_free = 0;
b9473439 3266 struct extent_buffer *must_clean = NULL;
78fae27e 3267
5d4f98a2
YZ		 3268 if (found_extent) {
3269 BUG_ON(is_data && refs_to_drop !=
3270 extent_data_ref_count(root, path, iref));
3271 if (iref) {
3272 BUG_ON(path->slots[0] != extent_slot);
3273 } else {
3274 BUG_ON(path->slots[0] != extent_slot + 1);
3275 path->slots[0] = extent_slot;
3276 num_to_del = 2;
3277 }
78fae27e 3278 }
b9473439 3279
5d4f98a2
YZ		 3280 ret = pin_down_bytes(trans, root, path, bytenr,
3281 num_bytes, is_data, &must_clean);
3282 if (ret > 0)
3283 mark_free = 1;
3284 BUG_ON(ret < 0);
b9473439
CM		 3285 /*
3286 * it is going to be very rare for someone to be waiting
3287 * on the block we're freeing. del_items might need to
3288 * schedule, so rather than get fancy, just force it
3289 * to blocking here
3290 */
3291 if (must_clean)
3292 btrfs_set_lock_blocking(must_clean);
3293
952fccac
CM		 3294 ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
3295 num_to_del);
31840ae1 3296 BUG_ON(ret);
25179201 3297 btrfs_release_path(extent_root, path);
21af804c 3298
b9473439
CM		 3299 if (must_clean) {
3300 clean_tree_block(NULL, root, must_clean);
3301 btrfs_tree_unlock(must_clean);
3302 free_extent_buffer(must_clean);
3303 }
3304
5d4f98a2 3305 if (is_data) {
459931ec
CM		 3306 ret = btrfs_del_csums(trans, root, bytenr, num_bytes);
3307 BUG_ON(ret);
d57e62b8
CM		 3308 } else {
3309 invalidate_mapping_pages(info->btree_inode->i_mapping,
3310 bytenr >> PAGE_CACHE_SHIFT,
3311 (bytenr + num_bytes - 1) >> PAGE_CACHE_SHIFT);
459931ec
CM		 3312 }
3313
dcbdd4dc
CM		 3314 ret = update_block_group(trans, root, bytenr, num_bytes, 0,
3315 mark_free);
3316 BUG_ON(ret);
a28ec197 3317 }
5caf2a00 3318 btrfs_free_path(path);
a28ec197
CM		 3319 return ret;
3320}
3321
1887be66
CM		 3322/*
3323 * when we free an extent, it is possible (and likely) that we free the last
3324 * delayed ref for that extent as well. This searches the delayed ref tree for
3325 * a given extent, and if there are no other delayed refs to be processed, it
3326 * removes it from the tree.
3327 */
3328static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans,
3329 struct btrfs_root *root, u64 bytenr)
3330{
3331 struct btrfs_delayed_ref_head *head;
3332 struct btrfs_delayed_ref_root *delayed_refs;
3333 struct btrfs_delayed_ref_node *ref;
3334 struct rb_node *node;
3335 int ret;
3336
3337 delayed_refs = &trans->transaction->delayed_refs;
3338 spin_lock(&delayed_refs->lock);
3339 head = btrfs_find_delayed_ref_head(trans, bytenr);
3340 if (!head)
3341 goto out;
3342
3343 node = rb_prev(&head->node.rb_node);
3344 if (!node)
3345 goto out;
3346
3347 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
3348
3349 /* there are still entries for this ref, we can't drop it */
3350 if (ref->bytenr == bytenr)
3351 goto out;
3352
5d4f98a2
YZ		 3353 if (head->extent_op) {
3354 if (!head->must_insert_reserved)
3355 goto out;
3356 kfree(head->extent_op);
3357 head->extent_op = NULL;
3358 }
3359
1887be66
CM		 3360 /*
3361 * waiting for the lock here would deadlock. If someone else has it
3362 * locked they are already in the process of dropping it anyway
3363 */
3364 if (!mutex_trylock(&head->mutex))
3365 goto out;
3366
3367 /*
3368 * at this point we have a head with no other entries. Go
3369 * ahead and process it.
3370 */
3371 head->node.in_tree = 0;
3372 rb_erase(&head->node.rb_node, &delayed_refs->root);
c3e69d58 3373
1887be66
CM		 3374 delayed_refs->num_entries--;
3375
3376 /*
3377 * we don't take a ref on the node because we're removing it from the
3378 * tree, so we just steal the ref the tree was holding.
3379 */
c3e69d58
CM		 3380 delayed_refs->num_heads--;
3381 if (list_empty(&head->cluster))
3382 delayed_refs->num_heads_ready--;
3383
3384 list_del_init(&head->cluster);
1887be66
CM		 3385 spin_unlock(&delayed_refs->lock);
3386
3387 ret = run_one_delayed_ref(trans, root->fs_info->tree_root,
5d4f98a2
YZ		 3388 &head->node, head->extent_op,
3389 head->must_insert_reserved);
1887be66
CM		 3390 BUG_ON(ret);
3391 btrfs_put_delayed_ref(&head->node);
3392 return 0;
3393out:
3394 spin_unlock(&delayed_refs->lock);
3395 return 0;
3396}
3397
925baedd 3398int btrfs_free_extent(struct btrfs_trans_handle *trans,
31840ae1
ZY		 3399 struct btrfs_root *root,
3400 u64 bytenr, u64 num_bytes, u64 parent,
5d4f98a2 3401 u64 root_objectid, u64 owner, u64 offset)
925baedd
CM		 3402{
3403 int ret;
3404
56bec294
CM		 3405 /*
3406 * tree log blocks never actually go into the extent allocation
3407 * tree, just update pinning info and exit early.
56bec294 3408 */
5d4f98a2
YZ		 3409 if (root_objectid == BTRFS_TREE_LOG_OBJECTID) {
3410 WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID);
b9473439 3411 /* unlocks the pinned mutex */
56bec294 3412 btrfs_update_pinned_extents(root, bytenr, num_bytes, 1);
56bec294
CM		 3413 update_reserved_extents(root, bytenr, num_bytes, 0);
3414 ret = 0;
5d4f98a2
YZ		 3415 } else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
3416 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
3417 parent, root_objectid, (int)owner,
3418 BTRFS_DROP_DELAYED_REF, NULL);
1887be66
CM		 3419 BUG_ON(ret);
3420 ret = check_ref_cleanup(trans, root, bytenr);
3421 BUG_ON(ret);
5d4f98a2
YZ		 3422 } else {
3423 ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes,
3424 parent, root_objectid, owner,
3425 offset, BTRFS_DROP_DELAYED_REF, NULL);
3426 BUG_ON(ret);
56bec294 3427 }
925baedd
CM		 3428 return ret;
3429}
3430
87ee04eb
CM		 3431static u64 stripe_align(struct btrfs_root *root, u64 val)
3432{
3433 u64 mask = ((u64)root->stripesize - 1);
3434 u64 ret = (val + mask) & ~mask;
3435 return ret;
3436}
3437
fec577fb
CM		 3438/*
3439 * walks the btree of allocated extents and find a hole of a given size.
3440 * The key ins is changed to record the hole:
3441 * ins->objectid == block start
62e2749e 3442 * ins->flags = BTRFS_EXTENT_ITEM_KEY
fec577fb
CM		 3443 * ins->offset == number of blocks
3444 * Any available blocks before search_start are skipped.
3445 */
d397712b 3446static noinline int find_free_extent(struct btrfs_trans_handle *trans,
98ed5174
CM		 3447 struct btrfs_root *orig_root,
3448 u64 num_bytes, u64 empty_size,
3449 u64 search_start, u64 search_end,
3450 u64 hint_byte, struct btrfs_key *ins,
3451 u64 exclude_start, u64 exclude_nr,
3452 int data)
fec577fb 3453{
80eb234a 3454 int ret = 0;
d397712b 3455 struct btrfs_root *root = orig_root->fs_info->extent_root;
fa9c0d79 3456 struct btrfs_free_cluster *last_ptr = NULL;
80eb234a 3457 struct btrfs_block_group_cache *block_group = NULL;
239b14b3 3458 int empty_cluster = 2 * 1024 * 1024;
0ef3e66b 3459 int allowed_chunk_alloc = 0;
80eb234a 3460 struct btrfs_space_info *space_info;
fa9c0d79
CM		 3461 int last_ptr_loop = 0;
3462 int loop = 0;
fec577fb 3463
db94535d 3464 WARN_ON(num_bytes < root->sectorsize);
b1a4d965 3465 btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
80eb234a
JB		 3466 ins->objectid = 0;
3467 ins->offset = 0;
b1a4d965 3468
2552d17e
JB		 3469 space_info = __find_space_info(root->fs_info, data);
3470
0ef3e66b
CM		 3471 if (orig_root->ref_cows || empty_size)
3472 allowed_chunk_alloc = 1;
3473
239b14b3 3474 if (data & BTRFS_BLOCK_GROUP_METADATA) {
fa9c0d79 3475 last_ptr = &root->fs_info->meta_alloc_cluster;
536ac8ae
CM		 3476 if (!btrfs_test_opt(root, SSD))
3477 empty_cluster = 64 * 1024;
239b14b3
CM		 3478 }
3479
fa9c0d79
CM		 3480 if ((data & BTRFS_BLOCK_GROUP_DATA) && btrfs_test_opt(root, SSD)) {
3481 last_ptr = &root->fs_info->data_alloc_cluster;
3482 }
0f9dd46c 3483
239b14b3 3484 if (last_ptr) {
fa9c0d79
CM		 3485 spin_lock(&last_ptr->lock);
3486 if (last_ptr->block_group)
3487 hint_byte = last_ptr->window_start;
3488 spin_unlock(&last_ptr->lock);
239b14b3 3489 }
fa9c0d79 3490
a061fc8d 3491 search_start = max(search_start, first_logical_byte(root, 0));
239b14b3 3492 search_start = max(search_start, hint_byte);
0b86a832 3493
fa9c0d79
CM		 3494 if (!last_ptr) {
3495 empty_cluster = 0;
3496 loop = 1;
3497 }
3498
2552d17e 3499 if (search_start == hint_byte) {
2552d17e
JB		 3500 block_group = btrfs_lookup_block_group(root->fs_info,
3501 search_start);
3502 if (block_group && block_group_bits(block_group, data)) {
2552d17e 3503 down_read(&space_info->groups_sem);
44fb5511
CM		 3504 if (list_empty(&block_group->list) ||
3505 block_group->ro) {
3506 /*
3507 * someone is removing this block group,
3508 * we can't jump into the have_block_group
3509 * target because our list pointers are not
3510 * valid
3511 */
3512 btrfs_put_block_group(block_group);
3513 up_read(&space_info->groups_sem);
3514 } else
3515 goto have_block_group;
2552d17e 3516 } else if (block_group) {
fa9c0d79 3517 btrfs_put_block_group(block_group);
2552d17e 3518 }
42e70e7a 3519 }
4366211c 3520
2552d17e 3521search:
80eb234a 3522 down_read(&space_info->groups_sem);
2552d17e 3523 list_for_each_entry(block_group, &space_info->block_groups, list) {
6226cb0a 3524 u64 offset;
8a1413a2 3525
2552d17e
JB		 3526 atomic_inc(&block_group->count);
3527 search_start = block_group->key.objectid;
42e70e7a 3528
2552d17e 3529have_block_group:
ea6a478e
JB		 3530 if (unlikely(!block_group->cached)) {
3531 mutex_lock(&block_group->cache_mutex);
3532 ret = cache_block_group(root, block_group);
3533 mutex_unlock(&block_group->cache_mutex);
2552d17e 3534 if (ret) {
fa9c0d79 3535 btrfs_put_block_group(block_group);
ea6a478e 3536 break;
2552d17e 3537 }
ea6a478e
JB		 3538 }
3539
ea6a478e 3540 if (unlikely(block_group->ro))
2552d17e 3541 goto loop;
0f9dd46c 3542
fa9c0d79
CM		 3543 if (last_ptr) {
3544 /*
3545 * the refill lock keeps out other
3546 * people trying to start a new cluster
3547 */
3548 spin_lock(&last_ptr->refill_lock);
44fb5511
CM		 3549 if (last_ptr->block_group &&
3550 (last_ptr->block_group->ro ||
3551 !block_group_bits(last_ptr->block_group, data))) {
3552 offset = 0;
3553 goto refill_cluster;
3554 }
3555
fa9c0d79
CM		 3556 offset = btrfs_alloc_from_cluster(block_group, last_ptr,
3557 num_bytes, search_start);
3558 if (offset) {
3559 /* we have a block, we're done */
3560 spin_unlock(&last_ptr->refill_lock);
3561 goto checks;
3562 }
3563
3564 spin_lock(&last_ptr->lock);
3565 /*
3566 * whoops, this cluster doesn't actually point to
3567 * this block group. Get a ref on the block
3568 * group is does point to and try again
3569 */
3570 if (!last_ptr_loop && last_ptr->block_group &&
3571 last_ptr->block_group != block_group) {
3572
3573 btrfs_put_block_group(block_group);
3574 block_group = last_ptr->block_group;
3575 atomic_inc(&block_group->count);
3576 spin_unlock(&last_ptr->lock);
3577 spin_unlock(&last_ptr->refill_lock);
3578
3579 last_ptr_loop = 1;
3580 search_start = block_group->key.objectid;
44fb5511
CM		 3581 /*
3582 * we know this block group is properly
3583 * in the list because
3584 * btrfs_remove_block_group, drops the
3585 * cluster before it removes the block
3586 * group from the list
3587 */
fa9c0d79
CM		 3588 goto have_block_group;
3589 }
3590 spin_unlock(&last_ptr->lock);
44fb5511 3591refill_cluster:
fa9c0d79
CM		 3592 /*
3593 * this cluster didn't work out, free it and
3594 * start over
3595 */
3596 btrfs_return_cluster_to_free_space(NULL, last_ptr);
3597
3598 last_ptr_loop = 0;
3599
3600 /* allocate a cluster in this block group */
451d7585 3601 ret = btrfs_find_space_cluster(trans, root,
fa9c0d79
CM		 3602 block_group, last_ptr,
3603 offset, num_bytes,
3604 empty_cluster + empty_size);
3605 if (ret == 0) {
3606 /*
3607 * now pull our allocation out of this
3608 * cluster
3609 */
3610 offset = btrfs_alloc_from_cluster(block_group,
3611 last_ptr, num_bytes,
3612 search_start);
3613 if (offset) {
3614 /* we found one, proceed */
3615 spin_unlock(&last_ptr->refill_lock);
3616 goto checks;
3617 }
3618 }
3619 /*
3620 * at this point we either didn't find a cluster
3621 * or we weren't able to allocate a block from our
3622 * cluster. Free the cluster we've been trying
3623 * to use, and go to the next block group
3624 */
3625 if (loop < 2) {
3626 btrfs_return_cluster_to_free_space(NULL,
3627 last_ptr);
3628 spin_unlock(&last_ptr->refill_lock);
3629 goto loop;
3630 }
3631 spin_unlock(&last_ptr->refill_lock);
3632 }
3633
6226cb0a
JB		 3634 offset = btrfs_find_space_for_alloc(block_group, search_start,
3635 num_bytes, empty_size);
3636 if (!offset)
2552d17e 3637 goto loop;
fa9c0d79 3638checks:
6226cb0a 3639 search_start = stripe_align(root, offset);
80eb234a 3640
2552d17e 3641 /* move on to the next group */
6226cb0a
JB		 3642 if (search_start + num_bytes >= search_end) {
3643 btrfs_add_free_space(block_group, offset, num_bytes);
2552d17e 3644 goto loop;
6226cb0a 3645 }
25179201 3646
2552d17e
JB		 3647 /* move on to the next group */
3648 if (search_start + num_bytes >
6226cb0a
JB		 3649 block_group->key.objectid + block_group->key.offset) {
3650 btrfs_add_free_space(block_group, offset, num_bytes);
2552d17e 3651 goto loop;
6226cb0a 3652 }
f5a31e16 3653
2552d17e
JB		 3654 if (exclude_nr > 0 &&
3655 (search_start + num_bytes > exclude_start &&
3656 search_start < exclude_start + exclude_nr)) {
3657 search_start = exclude_start + exclude_nr;
3658
6226cb0a 3659 btrfs_add_free_space(block_group, offset, num_bytes);
2552d17e
JB		 3660 /*
3661 * if search_start is still in this block group
3662 * then we just re-search this block group
f5a31e16 3663 */
2552d17e
JB		 3664 if (search_start >= block_group->key.objectid &&
3665 search_start < (block_group->key.objectid +
6226cb0a 3666 block_group->key.offset))
2552d17e 3667 goto have_block_group;
2552d17e 3668 goto loop;
0f9dd46c 3669 }
0b86a832 3670
2552d17e
JB		 3671 ins->objectid = search_start;
3672 ins->offset = num_bytes;
d2fb3437 3673
6226cb0a
JB		 3674 if (offset < search_start)
3675 btrfs_add_free_space(block_group, offset,
3676 search_start - offset);
3677 BUG_ON(offset > search_start);
3678
2552d17e 3679 /* we are all good, lets return */
2552d17e
JB		 3680 break;
3681loop:
fa9c0d79 3682 btrfs_put_block_group(block_group);
2552d17e
JB		 3683 }
3684 up_read(&space_info->groups_sem);
3685
fa9c0d79
CM		 3686 /* loop == 0, try to find a clustered alloc in every block group
3687 * loop == 1, try again after forcing a chunk allocation
3688 * loop == 2, set empty_size and empty_cluster to 0 and try again
3689 */
3690 if (!ins->objectid && loop < 3 &&
3691 (empty_size || empty_cluster || allowed_chunk_alloc)) {
3692 if (loop >= 2) {
3693 empty_size = 0;
3694 empty_cluster = 0;
3695 }
2552d17e
JB		 3696
3697 if (allowed_chunk_alloc) {
3698 ret = do_chunk_alloc(trans, root, num_bytes +
3699 2 * 1024 * 1024, data, 1);
2552d17e
JB		 3700 allowed_chunk_alloc = 0;
3701 } else {
3702 space_info->force_alloc = 1;
3703 }
3704
fa9c0d79
CM		 3705 if (loop < 3) {
3706 loop++;
2552d17e 3707 goto search;
fa9c0d79 3708 }
2552d17e
JB		 3709 ret = -ENOSPC;
3710 } else if (!ins->objectid) {
3711 ret = -ENOSPC;
f2654de4 3712 }
0b86a832 3713
80eb234a
JB		 3714 /* we found what we needed */
3715 if (ins->objectid) {
3716 if (!(data & BTRFS_BLOCK_GROUP_DATA))
d2fb3437 3717 trans->block_group = block_group->key.objectid;
0f9dd46c 3718
fa9c0d79 3719 btrfs_put_block_group(block_group);
80eb234a 3720 ret = 0;
be744175 3721 }
be744175 3722
0f70abe2 3723 return ret;
fec577fb 3724}
ec44a35c 3725
0f9dd46c
JB		 3726static void dump_space_info(struct btrfs_space_info *info, u64 bytes)
3727{
3728 struct btrfs_block_group_cache *cache;
0f9dd46c 3729
d397712b
CM		 3730 printk(KERN_INFO "space_info has %llu free, is %sfull\n",
3731 (unsigned long long)(info->total_bytes - info->bytes_used -
3732 info->bytes_pinned - info->bytes_reserved),
3733 (info->full) ? "" : "not ");
6a63209f 3734 printk(KERN_INFO "space_info total=%llu, pinned=%llu, delalloc=%llu,"
21380931
JB		 3735 " may_use=%llu, used=%llu\n",
3736 (unsigned long long)info->total_bytes,
3737 (unsigned long long)info->bytes_pinned,
3738 (unsigned long long)info->bytes_delalloc,
3739 (unsigned long long)info->bytes_may_use,
3740 (unsigned long long)info->bytes_used);
0f9dd46c 3741
80eb234a 3742 down_read(&info->groups_sem);
c6e30871 3743 list_for_each_entry(cache, &info->block_groups, list) {
0f9dd46c 3744 spin_lock(&cache->lock);
d397712b
CM		 3745 printk(KERN_INFO "block group %llu has %llu bytes, %llu used "
3746 "%llu pinned %llu reserved\n",
3747 (unsigned long long)cache->key.objectid,
3748 (unsigned long long)cache->key.offset,
3749 (unsigned long long)btrfs_block_group_used(&cache->item),
3750 (unsigned long long)cache->pinned,
3751 (unsigned long long)cache->reserved);
0f9dd46c
JB		 3752 btrfs_dump_free_space(cache, bytes);
3753 spin_unlock(&cache->lock);
3754 }
80eb234a 3755 up_read(&info->groups_sem);
0f9dd46c 3756}
e8569813 3757
e6dcd2dc
CM		 3758static int __btrfs_reserve_extent(struct btrfs_trans_handle *trans,
3759 struct btrfs_root *root,
3760 u64 num_bytes, u64 min_alloc_size,
3761 u64 empty_size, u64 hint_byte,
3762 u64 search_end, struct btrfs_key *ins,
3763 u64 data)
fec577fb
CM		 3764{
3765 int ret;
fbdc762b 3766 u64 search_start = 0;
1261ec42 3767 struct btrfs_fs_info *info = root->fs_info;
925baedd 3768
6a63209f 3769 data = btrfs_get_alloc_profile(root, data);
98d20f67 3770again:
0ef3e66b
CM		 3771 /*
3772 * the only place that sets empty_size is btrfs_realloc_node, which
3773 * is not called recursively on allocations
3774 */
3775 if (empty_size || root->ref_cows) {
593060d7 3776 if (!(data & BTRFS_BLOCK_GROUP_METADATA)) {
6324fbf3 3777 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
0ef3e66b
CM		 3778 2 * 1024 * 1024,
3779 BTRFS_BLOCK_GROUP_METADATA |
3780 (info->metadata_alloc_profile &
3781 info->avail_metadata_alloc_bits), 0);
6324fbf3
CM		 3782 }
3783 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
0ef3e66b 3784 num_bytes + 2 * 1024 * 1024, data, 0);
6324fbf3 3785 }
0b86a832 3786
db94535d
CM		 3787 WARN_ON(num_bytes < root->sectorsize);
3788 ret = find_free_extent(trans, root, num_bytes, empty_size,
3789 search_start, search_end, hint_byte, ins,
26b8003f
CM		 3790 trans->alloc_exclude_start,
3791 trans->alloc_exclude_nr, data);
3b951516 3792
98d20f67
CM		 3793 if (ret == -ENOSPC && num_bytes > min_alloc_size) {
3794 num_bytes = num_bytes >> 1;
0f9dd46c 3795 num_bytes = num_bytes & ~(root->sectorsize - 1);
98d20f67 3796 num_bytes = max(num_bytes, min_alloc_size);
0ef3e66b
CM		 3797 do_chunk_alloc(trans, root->fs_info->extent_root,
3798 num_bytes, data, 1);
98d20f67
CM		 3799 goto again;
3800 }
ec44a35c 3801 if (ret) {
0f9dd46c
JB		 3802 struct btrfs_space_info *sinfo;
3803
3804 sinfo = __find_space_info(root->fs_info, data);
d397712b
CM		 3805 printk(KERN_ERR "btrfs allocation failed flags %llu, "
3806 "wanted %llu\n", (unsigned long long)data,
3807 (unsigned long long)num_bytes);
0f9dd46c 3808 dump_space_info(sinfo, num_bytes);
925baedd 3809 BUG();
925baedd 3810 }
0f9dd46c
JB		 3811
3812 return ret;
e6dcd2dc
CM		 3813}
3814
65b51a00
CM		 3815int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len)
3816{
0f9dd46c 3817 struct btrfs_block_group_cache *cache;
1f3c79a2 3818 int ret = 0;
0f9dd46c 3819
0f9dd46c
JB		 3820 cache = btrfs_lookup_block_group(root->fs_info, start);
3821 if (!cache) {
d397712b
CM		 3822 printk(KERN_ERR "Unable to find block group for %llu\n",
3823 (unsigned long long)start);
0f9dd46c
JB		 3824 return -ENOSPC;
3825 }
1f3c79a2
LH		 3826
3827 ret = btrfs_discard_extent(root, start, len);
3828
0f9dd46c 3829 btrfs_add_free_space(cache, start, len);
fa9c0d79 3830 btrfs_put_block_group(cache);
1a40e23b 3831 update_reserved_extents(root, start, len, 0);
1f3c79a2
LH		 3832
3833 return ret;
65b51a00
CM		 3834}
3835
e6dcd2dc
CM		 3836int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
3837 struct btrfs_root *root,
3838 u64 num_bytes, u64 min_alloc_size,
3839 u64 empty_size, u64 hint_byte,
3840 u64 search_end, struct btrfs_key *ins,
3841 u64 data)
3842{
3843 int ret;
e6dcd2dc
CM		 3844 ret = __btrfs_reserve_extent(trans, root, num_bytes, min_alloc_size,
3845 empty_size, hint_byte, search_end, ins,
3846 data);
e8569813 3847 update_reserved_extents(root, ins->objectid, ins->offset, 1);
e6dcd2dc
CM		 3848 return ret;
3849}
3850
5d4f98a2
YZ		 3851static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
3852 struct btrfs_root *root,
3853 u64 parent, u64 root_objectid,
3854 u64 flags, u64 owner, u64 offset,
3855 struct btrfs_key *ins, int ref_mod)
e6dcd2dc
CM		 3856{
3857 int ret;
5d4f98a2 3858 struct btrfs_fs_info *fs_info = root->fs_info;
e6dcd2dc 3859 struct btrfs_extent_item *extent_item;
5d4f98a2 3860 struct btrfs_extent_inline_ref *iref;
e6dcd2dc 3861 struct btrfs_path *path;
5d4f98a2
YZ		 3862 struct extent_buffer *leaf;
3863 int type;
3864 u32 size;
26b8003f 3865
5d4f98a2
YZ		 3866 if (parent > 0)
3867 type = BTRFS_SHARED_DATA_REF_KEY;
3868 else
3869 type = BTRFS_EXTENT_DATA_REF_KEY;
58176a96 3870
5d4f98a2 3871 size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type);
7bb86316
CM		 3872
3873 path = btrfs_alloc_path();
3874 BUG_ON(!path);
47e4bb98 3875
b9473439 3876 path->leave_spinning = 1;
5d4f98a2
YZ		 3877 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
3878 ins, size);
ccd467d6 3879 BUG_ON(ret);
0f9dd46c 3880
5d4f98a2
YZ		 3881 leaf = path->nodes[0];
3882 extent_item = btrfs_item_ptr(leaf, path->slots[0],
47e4bb98 3883 struct btrfs_extent_item);
5d4f98a2
YZ		 3884 btrfs_set_extent_refs(leaf, extent_item, ref_mod);
3885 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
3886 btrfs_set_extent_flags(leaf, extent_item,
3887 flags | BTRFS_EXTENT_FLAG_DATA);
3888
3889 iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
3890 btrfs_set_extent_inline_ref_type(leaf, iref, type);
3891 if (parent > 0) {
3892 struct btrfs_shared_data_ref *ref;
3893 ref = (struct btrfs_shared_data_ref *)(iref + 1);
3894 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
3895 btrfs_set_shared_data_ref_count(leaf, ref, ref_mod);
3896 } else {
3897 struct btrfs_extent_data_ref *ref;
3898 ref = (struct btrfs_extent_data_ref *)(&iref->offset);
3899 btrfs_set_extent_data_ref_root(leaf, ref, root_objectid);
3900 btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
3901 btrfs_set_extent_data_ref_offset(leaf, ref, offset);
3902 btrfs_set_extent_data_ref_count(leaf, ref, ref_mod);
3903 }
47e4bb98
CM		 3904
3905 btrfs_mark_buffer_dirty(path->nodes[0]);
7bb86316 3906 btrfs_free_path(path);
f510cfec 3907
5d4f98a2
YZ		 3908 ret = update_block_group(trans, root, ins->objectid, ins->offset,
3909 1, 0);
f5947066 3910 if (ret) {
d397712b
CM		 3911 printk(KERN_ERR "btrfs update block group failed for %llu "
3912 "%llu\n", (unsigned long long)ins->objectid,
3913 (unsigned long long)ins->offset);
f5947066
CM		 3914 BUG();
3915 }
e6dcd2dc
CM		 3916 return ret;
3917}
3918
5d4f98a2
YZ		 3919static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
3920 struct btrfs_root *root,
3921 u64 parent, u64 root_objectid,
3922 u64 flags, struct btrfs_disk_key *key,
3923 int level, struct btrfs_key *ins)
e6dcd2dc
CM		 3924{
3925 int ret;
5d4f98a2
YZ		 3926 struct btrfs_fs_info *fs_info = root->fs_info;
3927 struct btrfs_extent_item *extent_item;
3928 struct btrfs_tree_block_info *block_info;
3929 struct btrfs_extent_inline_ref *iref;
3930 struct btrfs_path *path;
3931 struct extent_buffer *leaf;
3932 u32 size = sizeof(*extent_item) + sizeof(*block_info) + sizeof(*iref);
1c2308f8 3933
5d4f98a2
YZ		 3934 path = btrfs_alloc_path();
3935 BUG_ON(!path);
56bec294 3936
5d4f98a2
YZ		 3937 path->leave_spinning = 1;
3938 ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
3939 ins, size);
56bec294 3940 BUG_ON(ret);
5d4f98a2
YZ		 3941
3942 leaf = path->nodes[0];
3943 extent_item = btrfs_item_ptr(leaf, path->slots[0],
3944 struct btrfs_extent_item);
3945 btrfs_set_extent_refs(leaf, extent_item, 1);
3946 btrfs_set_extent_generation(leaf, extent_item, trans->transid);
3947 btrfs_set_extent_flags(leaf, extent_item,
3948 flags | BTRFS_EXTENT_FLAG_TREE_BLOCK);
3949 block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
3950
3951 btrfs_set_tree_block_key(leaf, block_info, key);
3952 btrfs_set_tree_block_level(leaf, block_info, level);
3953
3954 iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
3955 if (parent > 0) {
3956 BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF));
3957 btrfs_set_extent_inline_ref_type(leaf, iref,
3958 BTRFS_SHARED_BLOCK_REF_KEY);
3959 btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
3960 } else {
3961 btrfs_set_extent_inline_ref_type(leaf, iref,
3962 BTRFS_TREE_BLOCK_REF_KEY);
3963 btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
3964 }
3965
3966 btrfs_mark_buffer_dirty(leaf);
3967 btrfs_free_path(path);
3968
3969 ret = update_block_group(trans, root, ins->objectid, ins->offset,
3970 1, 0);
3971 if (ret) {
3972 printk(KERN_ERR "btrfs update block group failed for %llu "
3973 "%llu\n", (unsigned long long)ins->objectid,
3974 (unsigned long long)ins->offset);
3975 BUG();
3976 }
3977 return ret;
3978}
3979
3980int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
3981 struct btrfs_root *root,
3982 u64 root_objectid, u64 owner,
3983 u64 offset, struct btrfs_key *ins)
3984{
3985 int ret;
3986
3987 BUG_ON(root_objectid == BTRFS_TREE_LOG_OBJECTID);
3988
3989 ret = btrfs_add_delayed_data_ref(trans, ins->objectid, ins->offset,
3990 0, root_objectid, owner, offset,
3991 BTRFS_ADD_DELAYED_EXTENT, NULL);
e6dcd2dc
CM		 3992 return ret;
3993}
e02119d5
CM		 3994
3995/*
3996 * this is used by the tree logging recovery code. It records that
3997 * an extent has been allocated and makes sure to clear the free
3998 * space cache bits as well
3999 */
5d4f98a2
YZ		 4000int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
4001 struct btrfs_root *root,
4002 u64 root_objectid, u64 owner, u64 offset,
4003 struct btrfs_key *ins)
e02119d5
CM		 4004{
4005 int ret;
4006 struct btrfs_block_group_cache *block_group;
4007
e02119d5 4008 block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
ea6a478e 4009 mutex_lock(&block_group->cache_mutex);
e02119d5 4010 cache_block_group(root, block_group);
ea6a478e 4011 mutex_unlock(&block_group->cache_mutex);
e02119d5 4012
ea6a478e
JB		 4013 ret = btrfs_remove_free_space(block_group, ins->objectid,
4014 ins->offset);
0f9dd46c 4015 BUG_ON(ret);
fa9c0d79 4016 btrfs_put_block_group(block_group);
5d4f98a2
YZ		 4017 ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,
4018 0, owner, offset, ins, 1);
e02119d5
CM		 4019 return ret;
4020}
4021
e6dcd2dc
CM		 4022/*
4023 * finds a free extent and does all the dirty work required for allocation
4024 * returns the key for the extent through ins, and a tree buffer for
4025 * the first block of the extent through buf.
4026 *
4027 * returns 0 if everything worked, non-zero otherwise.
4028 */
5d4f98a2
YZ		 4029static int alloc_tree_block(struct btrfs_trans_handle *trans,
4030 struct btrfs_root *root,
4031 u64 num_bytes, u64 parent, u64 root_objectid,
4032 struct btrfs_disk_key *key, int level,
4033 u64 empty_size, u64 hint_byte, u64 search_end,
4034 struct btrfs_key *ins)
e6dcd2dc
CM		 4035{
4036 int ret;
5d4f98a2
YZ		 4037 u64 flags = 0;
4038
4039 ret = __btrfs_reserve_extent(trans, root, num_bytes, num_bytes,
4040 empty_size, hint_byte, search_end,
4041 ins, 0);
e6dcd2dc 4042 BUG_ON(ret);
5d4f98a2
YZ		 4043
4044 if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
4045 if (parent == 0)
4046 parent = ins->objectid;
4047 flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
4048 } else
4049 BUG_ON(parent > 0);
4050
4051 update_reserved_extents(root, ins->objectid, ins->offset, 1);
d00aff00 4052 if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
5d4f98a2
YZ		 4053 struct btrfs_delayed_extent_op *extent_op;
4054 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
4055 BUG_ON(!extent_op);
4056 if (key)
4057 memcpy(&extent_op->key, key, sizeof(extent_op->key));
4058 else
4059 memset(&extent_op->key, 0, sizeof(extent_op->key));
4060 extent_op->flags_to_set = flags;
4061 extent_op->update_key = 1;
4062 extent_op->update_flags = 1;
4063 extent_op->is_data = 0;
4064
4065 ret = btrfs_add_delayed_tree_ref(trans, ins->objectid,
4066 ins->offset, parent, root_objectid,
4067 level, BTRFS_ADD_DELAYED_EXTENT,
4068 extent_op);
d00aff00 4069 BUG_ON(ret);
d00aff00 4070 }
925baedd 4071 return ret;
fec577fb 4072}
65b51a00
CM		 4073
4074struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
4075 struct btrfs_root *root,
4008c04a
CM		 4076 u64 bytenr, u32 blocksize,
4077 int level)
65b51a00
CM		 4078{
4079 struct extent_buffer *buf;
4080
4081 buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
4082 if (!buf)
4083 return ERR_PTR(-ENOMEM);
4084 btrfs_set_header_generation(buf, trans->transid);
4008c04a 4085 btrfs_set_buffer_lockdep_class(buf, level);
65b51a00
CM		 4086 btrfs_tree_lock(buf);
4087 clean_tree_block(trans, root, buf);
b4ce94de
CM		 4088
4089 btrfs_set_lock_blocking(buf);
65b51a00 4090 btrfs_set_buffer_uptodate(buf);
b4ce94de 4091
d0c803c4
CM		 4092 if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
4093 set_extent_dirty(&root->dirty_log_pages, buf->start,
4094 buf->start + buf->len - 1, GFP_NOFS);
4095 } else {
4096 set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
65b51a00 4097 buf->start + buf->len - 1, GFP_NOFS);
d0c803c4 4098 }
65b51a00 4099 trans->blocks_used++;
b4ce94de 4100 /* this returns a buffer locked for blocking */
65b51a00
CM		 4101 return buf;
4102}
4103
fec577fb
CM		 4104/*
4105 * helper function to allocate a block for a given tree
4106 * returns the tree buffer or NULL.
4107 */
5f39d397 4108struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
5d4f98a2
YZ		 4109 struct btrfs_root *root, u32 blocksize,
4110 u64 parent, u64 root_objectid,
4111 struct btrfs_disk_key *key, int level,
4112 u64 hint, u64 empty_size)
fec577fb 4113{
e2fa7227 4114 struct btrfs_key ins;
fec577fb 4115 int ret;
5f39d397 4116 struct extent_buffer *buf;
fec577fb 4117
5d4f98a2
YZ		 4118 ret = alloc_tree_block(trans, root, blocksize, parent, root_objectid,
4119 key, level, empty_size, hint, (u64)-1, &ins);
fec577fb 4120 if (ret) {
54aa1f4d
CM		 4121 BUG_ON(ret > 0);
4122 return ERR_PTR(ret);
fec577fb 4123 }
55c69072 4124
4008c04a
CM		 4125 buf = btrfs_init_new_buffer(trans, root, ins.objectid,
4126 blocksize, level);
fec577fb
CM		 4127 return buf;
4128}
a28ec197 4129
2c47e605 4130#if 0
e02119d5
CM		 4131int btrfs_drop_leaf_ref(struct btrfs_trans_handle *trans,
4132 struct btrfs_root *root, struct extent_buffer *leaf)
6407bf6d 4133{
5d4f98a2
YZ		 4134 u64 disk_bytenr;
4135 u64 num_bytes;
5f39d397 4136 struct btrfs_key key;
6407bf6d 4137 struct btrfs_file_extent_item *fi;
5d4f98a2 4138 u32 nritems;
6407bf6d 4139 int i;
6407bf6d
CM		 4140 int ret;
4141
5f39d397
CM		 4142 BUG_ON(!btrfs_is_leaf(leaf));
4143 nritems = btrfs_header_nritems(leaf);
7bb86316 4144
6407bf6d 4145 for (i = 0; i < nritems; i++) {
e34a5b4f 4146 cond_resched();
5f39d397 4147 btrfs_item_key_to_cpu(leaf, &key, i);
bd56b302
CM		 4148
4149 /* only extents have references, skip everything else */
5f39d397 4150 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
6407bf6d 4151 continue;
bd56b302 4152
6407bf6d 4153 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
bd56b302
CM		 4154
4155 /* inline extents live in the btree, they don't have refs */
5f39d397
CM		 4156 if (btrfs_file_extent_type(leaf, fi) ==
4157 BTRFS_FILE_EXTENT_INLINE)
236454df 4158 continue;
bd56b302 4159
db94535d 4160 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
bd56b302
CM		 4161
4162 /* holes don't have refs */
db94535d 4163 if (disk_bytenr == 0)
3a686375 4164 continue;
4a096752 4165
5d4f98a2
YZ		 4166 num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
4167 ret = btrfs_free_extent(trans, root, disk_bytenr, num_bytes,
4168 leaf->start, 0, key.objectid, 0);
31840ae1 4169 BUG_ON(ret);
6407bf6d
CM		 4170 }
4171 return 0;
4172}
4173
d397712b 4174static noinline int cache_drop_leaf_ref(struct btrfs_trans_handle *trans,
e02119d5
CM		 4175 struct btrfs_root *root,
4176 struct btrfs_leaf_ref *ref)
31153d81
YZ		 4177{
4178 int i;
4179 int ret;
bd56b302
CM		 4180 struct btrfs_extent_info *info;
4181 struct refsort *sorted;
4182
4183 if (ref->nritems == 0)
4184 return 0;
31153d81 4185
bd56b302
CM		 4186 sorted = kmalloc(sizeof(*sorted) * ref->nritems, GFP_NOFS);
4187 for (i = 0; i < ref->nritems; i++) {
4188 sorted[i].bytenr = ref->extents[i].bytenr;
4189 sorted[i].slot = i;
4190 }
4191 sort(sorted, ref->nritems, sizeof(struct refsort), refsort_cmp, NULL);
4192
4193 /*
4194 * the items in the ref were sorted when the ref was inserted
4195 * into the ref cache, so this is already in order
4196 */
31153d81 4197 for (i = 0; i < ref->nritems; i++) {
bd56b302 4198 info = ref->extents + sorted[i].slot;
56bec294 4199 ret = btrfs_free_extent(trans, root, info->bytenr,
31840ae1
ZY		 4200 info->num_bytes, ref->bytenr,
4201 ref->owner, ref->generation,
3bb1a1bc 4202 info->objectid, 0);
2dd3e67b
CM		 4203
4204 atomic_inc(&root->fs_info->throttle_gen);
4205 wake_up(&root->fs_info->transaction_throttle);
4206 cond_resched();
4207
31153d81
YZ		 4208 BUG_ON(ret);
4209 info++;
4210 }
31153d81 4211
806638bc 4212 kfree(sorted);
31153d81
YZ		 4213 return 0;
4214}
4215
5d4f98a2 4216
56bec294
CM		 4217static int drop_snap_lookup_refcount(struct btrfs_trans_handle *trans,
4218 struct btrfs_root *root, u64 start,
d397712b 4219 u64 len, u32 *refs)
333db94c 4220{
017e5369 4221 int ret;
f87f057b 4222
5d4f98a2 4223 ret = btrfs_lookup_extent_refs(trans, root, start, len, refs);
f87f057b
CM		 4224 BUG_ON(ret);
4225
d397712b 4226#if 0 /* some debugging code in case we see problems here */
f87f057b
CM		 4227 /* if the refs count is one, it won't get increased again. But
4228 * if the ref count is > 1, someone may be decreasing it at
4229 * the same time we are.
4230 */
4231 if (*refs != 1) {
4232 struct extent_buffer *eb = NULL;
4233 eb = btrfs_find_create_tree_block(root, start, len);
4234 if (eb)
4235 btrfs_tree_lock(eb);
4236
4237 mutex_lock(&root->fs_info->alloc_mutex);
4238 ret = lookup_extent_ref(NULL, root, start, len, refs);
4239 BUG_ON(ret);
4240 mutex_unlock(&root->fs_info->alloc_mutex);
4241
4242 if (eb) {
4243 btrfs_tree_unlock(eb);
4244 free_extent_buffer(eb);
4245 }
4246 if (*refs == 1) {
d397712b
CM		 4247 printk(KERN_ERR "btrfs block %llu went down to one "
4248 "during drop_snap\n", (unsigned long long)start);
f87f057b
CM		 4249 }
4250
4251 }
4252#endif
4253
e7a84565 4254 cond_resched();
017e5369 4255 return ret;
333db94c
CM		 4256}
4257
5d4f98a2 4258
bd56b302
CM		 4259/*
4260 * this is used while deleting old snapshots, and it drops the refs
4261 * on a whole subtree starting from a level 1 node.
4262 *
4263 * The idea is to sort all the leaf pointers, and then drop the
4264 * ref on all the leaves in order. Most of the time the leaves
4265 * will have ref cache entries, so no leaf IOs will be required to
4266 * find the extents they have references on.
4267 *
4268 * For each leaf, any references it has are also dropped in order
4269 *
4270 * This ends up dropping the references in something close to optimal
4271 * order for reading and modifying the extent allocation tree.
4272 */
4273static noinline int drop_level_one_refs(struct btrfs_trans_handle *trans,
4274 struct btrfs_root *root,
4275 struct btrfs_path *path)
4276{
4277 u64 bytenr;
4278 u64 root_owner;
4279 u64 root_gen;
4280 struct extent_buffer *eb = path->nodes[1];
4281 struct extent_buffer *leaf;
4282 struct btrfs_leaf_ref *ref;
4283 struct refsort *sorted = NULL;
4284 int nritems = btrfs_header_nritems(eb);
4285 int ret;
4286 int i;
4287 int refi = 0;
4288 int slot = path->slots[1];
4289 u32 blocksize = btrfs_level_size(root, 0);
4290 u32 refs;
4291
4292 if (nritems == 0)
4293 goto out;
4294
4295 root_owner = btrfs_header_owner(eb);
4296 root_gen = btrfs_header_generation(eb);
4297 sorted = kmalloc(sizeof(*sorted) * nritems, GFP_NOFS);
4298
4299 /*
4300 * step one, sort all the leaf pointers so we don't scribble
4301 * randomly into the extent allocation tree
4302 */
4303 for (i = slot; i < nritems; i++) {
4304 sorted[refi].bytenr = btrfs_node_blockptr(eb, i);
4305 sorted[refi].slot = i;
4306 refi++;
4307 }
4308
4309 /*
4310 * nritems won't be zero, but if we're picking up drop_snapshot
4311 * after a crash, slot might be > 0, so double check things
4312 * just in case.
4313 */
4314 if (refi == 0)
4315 goto out;
4316
4317 sort(sorted, refi, sizeof(struct refsort), refsort_cmp, NULL);
4318
4319 /*
4320 * the first loop frees everything the leaves point to
4321 */
4322 for (i = 0; i < refi; i++) {
4323 u64 ptr_gen;
4324
4325 bytenr = sorted[i].bytenr;
4326
4327 /*
4328 * check the reference count on this leaf. If it is > 1
4329 * we just decrement it below and don't update any
4330 * of the refs the leaf points to.
4331 */
56bec294
CM		 4332 ret = drop_snap_lookup_refcount(trans, root, bytenr,
4333 blocksize, &refs);
bd56b302
CM		 4334 BUG_ON(ret);
4335 if (refs != 1)
4336 continue;
4337
4338 ptr_gen = btrfs_node_ptr_generation(eb, sorted[i].slot);
4339
4340 /*
4341 * the leaf only had one reference, which means the
4342 * only thing pointing to this leaf is the snapshot
4343 * we're deleting. It isn't possible for the reference
4344 * count to increase again later
4345 *
4346 * The reference cache is checked for the leaf,
4347 * and if found we'll be able to drop any refs held by
4348 * the leaf without needing to read it in.
4349 */
4350 ref = btrfs_lookup_leaf_ref(root, bytenr);
4351 if (ref && ref->generation != ptr_gen) {
4352 btrfs_free_leaf_ref(root, ref);
4353 ref = NULL;
4354 }
4355 if (ref) {
4356 ret = cache_drop_leaf_ref(trans, root, ref);
4357 BUG_ON(ret);
4358 btrfs_remove_leaf_ref(root, ref);
4359 btrfs_free_leaf_ref(root, ref);
4360 } else {
4361 /*
4362 * the leaf wasn't in the reference cache, so
4363 * we have to read it.
4364 */
4365 leaf = read_tree_block(root, bytenr, blocksize,
4366 ptr_gen);
4367 ret = btrfs_drop_leaf_ref(trans, root, leaf);
4368 BUG_ON(ret);
4369 free_extent_buffer(leaf);
4370 }
4371 atomic_inc(&root->fs_info->throttle_gen);
4372 wake_up(&root->fs_info->transaction_throttle);
4373 cond_resched();
4374 }
4375
4376 /*
4377 * run through the loop again to free the refs on the leaves.
4378 * This is faster than doing it in the loop above because
4379 * the leaves are likely to be clustered together. We end up
4380 * working in nice chunks on the extent allocation tree.
4381 */
4382 for (i = 0; i < refi; i++) {
4383 bytenr = sorted[i].bytenr;
56bec294 4384 ret = btrfs_free_extent(trans, root, bytenr,
bd56b302
CM		 4385 blocksize, eb->start,
4386 root_owner, root_gen, 0, 1);
4387 BUG_ON(ret);
4388
4389 atomic_inc(&root->fs_info->throttle_gen);
4390 wake_up(&root->fs_info->transaction_throttle);
4391 cond_resched();
4392 }
4393out:
4394 kfree(sorted);
4395
4396 /*
4397 * update the path to show we've processed the entire level 1
4398 * node. This will get saved into the root's drop_snapshot_progress
4399 * field so these drops are not repeated again if this transaction
4400 * commits.
4401 */
4402 path->slots[1] = nritems;
4403 return 0;
4404}
4405
9aca1d51
CM		 4406/*
4407 * helper function for drop_snapshot, this walks down the tree dropping ref
4408 * counts as it goes.
4409 */
d397712b 4410static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
98ed5174
CM		 4411 struct btrfs_root *root,
4412 struct btrfs_path *path, int *level)
20524f02 4413{
7bb86316
CM		 4414 u64 root_owner;
4415 u64 root_gen;
4416 u64 bytenr;
ca7a79ad 4417 u64 ptr_gen;
5f39d397
CM		 4418 struct extent_buffer *next;
4419 struct extent_buffer *cur;
7bb86316 4420 struct extent_buffer *parent;
db94535d 4421 u32 blocksize;
20524f02
CM		 4422 int ret;
4423 u32 refs;
4424
5caf2a00
CM		 4425 WARN_ON(*level < 0);
4426 WARN_ON(*level >= BTRFS_MAX_LEVEL);
56bec294 4427 ret = drop_snap_lookup_refcount(trans, root, path->nodes[*level]->start,
db94535d 4428 path->nodes[*level]->len, &refs);
20524f02
CM		 4429 BUG_ON(ret);
4430 if (refs > 1)
4431 goto out;
e011599b 4432
9aca1d51
CM		 4433 /*
4434 * walk down to the last node level and free all the leaves
4435 */
d397712b 4436 while (*level >= 0) {
5caf2a00
CM		 4437 WARN_ON(*level < 0);
4438 WARN_ON(*level >= BTRFS_MAX_LEVEL);
20524f02 4439 cur = path->nodes[*level];
e011599b 4440
5f39d397 4441 if (btrfs_header_level(cur) != *level)
2c90e5d6 4442 WARN_ON(1);
e011599b 4443
7518a238 4444 if (path->slots[*level] >=
5f39d397 4445 btrfs_header_nritems(cur))
20524f02 4446 break;
bd56b302
CM		 4447
4448 /* the new code goes down to level 1 and does all the
4449 * leaves pointed to that node in bulk. So, this check
4450 * for level 0 will always be false.
4451 *
4452 * But, the disk format allows the drop_snapshot_progress
4453 * field in the root to leave things in a state where
4454 * a leaf will need cleaning up here. If someone crashes
4455 * with the old code and then boots with the new code,
4456 * we might find a leaf here.
4457 */
6407bf6d 4458 if (*level == 0) {
e02119d5 4459 ret = btrfs_drop_leaf_ref(trans, root, cur);
6407bf6d
CM		 4460 BUG_ON(ret);
4461 break;
4462 }
bd56b302
CM		 4463
4464 /*
4465 * once we get to level one, process the whole node
4466 * at once, including everything below it.
4467 */
4468 if (*level == 1) {
4469 ret = drop_level_one_refs(trans, root, path);
4470 BUG_ON(ret);
4471 break;
4472 }
4473
db94535d 4474 bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
ca7a79ad 4475 ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
db94535d 4476 blocksize = btrfs_level_size(root, *level - 1);
925baedd 4477
56bec294
CM		 4478 ret = drop_snap_lookup_refcount(trans, root, bytenr,
4479 blocksize, &refs);
6407bf6d 4480 BUG_ON(ret);
bd56b302
CM		 4481
4482 /*
4483 * if there is more than one reference, we don't need
4484 * to read that node to drop any references it has. We
4485 * just drop the ref we hold on that node and move on to the
4486 * next slot in this level.
4487 */
6407bf6d 4488 if (refs != 1) {
7bb86316
CM		 4489 parent = path->nodes[*level];
4490 root_owner = btrfs_header_owner(parent);
4491 root_gen = btrfs_header_generation(parent);
20524f02 4492 path->slots[*level]++;
f87f057b 4493
56bec294 4494 ret = btrfs_free_extent(trans, root, bytenr,
31840ae1 4495 blocksize, parent->start,
3bb1a1bc
YZ		 4496 root_owner, root_gen,
4497 *level - 1, 1);
20524f02 4498 BUG_ON(ret);
18e35e0a
CM		 4499
4500 atomic_inc(&root->fs_info->throttle_gen);
4501 wake_up(&root->fs_info->transaction_throttle);
2dd3e67b 4502 cond_resched();
18e35e0a 4503
20524f02
CM		 4504 continue;
4505 }
bd56b302 4506
f87f057b 4507 /*
bd56b302
CM		 4508 * we need to keep freeing things in the next level down.
4509 * read the block and loop around to process it
f87f057b 4510 */
bd56b302 4511 next = read_tree_block(root, bytenr, blocksize, ptr_gen);
5caf2a00 4512 WARN_ON(*level <= 0);
83e15a28 4513 if (path->nodes[*level-1])
5f39d397 4514 free_extent_buffer(path->nodes[*level-1]);
20524f02 4515 path->nodes[*level-1] = next;
5f39d397 4516 *level = btrfs_header_level(next);
20524f02 4517 path->slots[*level] = 0;
2dd3e67b 4518 cond_resched();
20524f02
CM		 4519 }
4520out:
5caf2a00
CM		 4521 WARN_ON(*level < 0);
4522 WARN_ON(*level >= BTRFS_MAX_LEVEL);
7bb86316
CM		 4523
4524 if (path->nodes[*level] == root->node) {
7bb86316 4525 parent = path->nodes[*level];
31153d81 4526 bytenr = path->nodes[*level]->start;
7bb86316
CM		 4527 } else {
4528 parent = path->nodes[*level + 1];
31153d81 4529 bytenr = btrfs_node_blockptr(parent, path->slots[*level + 1]);
7bb86316
CM		 4530 }
4531
31153d81
YZ		 4532 blocksize = btrfs_level_size(root, *level);
4533 root_owner = btrfs_header_owner(parent);
7bb86316 4534 root_gen = btrfs_header_generation(parent);
31153d81 4535
bd56b302
CM		 4536 /*
4537 * cleanup and free the reference on the last node
4538 * we processed
4539 */
56bec294 4540 ret = btrfs_free_extent(trans, root, bytenr, blocksize,
31840ae1 4541 parent->start, root_owner, root_gen,
3bb1a1bc 4542 *level, 1);
5f39d397 4543 free_extent_buffer(path->nodes[*level]);
20524f02 4544 path->nodes[*level] = NULL;
bd56b302 4545
20524f02
CM		 4546 *level += 1;
4547 BUG_ON(ret);
f87f057b 4548
e7a84565 4549 cond_resched();
20524f02
CM		 4550 return 0;
4551}
5d4f98a2 4552#endif
20524f02 4553
2c47e605
YZ		 4554struct walk_control {
4555 u64 refs[BTRFS_MAX_LEVEL];
4556 u64 flags[BTRFS_MAX_LEVEL];
4557 struct btrfs_key update_progress;
4558 int stage;
4559 int level;
4560 int shared_level;
4561 int update_ref;
4562 int keep_locks;
4563};
4564
4565#define DROP_REFERENCE 1
4566#define UPDATE_BACKREF 2
4567
f82d02d9 4568/*
2c47e605
YZ		 4569 * hepler to process tree block while walking down the tree.
4570 *
4571 * when wc->stage == DROP_REFERENCE, this function checks
4572 * reference count of the block. if the block is shared and
4573 * we need update back refs for the subtree rooted at the
4574 * block, this function changes wc->stage to UPDATE_BACKREF
4575 *
4576 * when wc->stage == UPDATE_BACKREF, this function updates
4577 * back refs for pointers in the block.
4578 *
4579 * NOTE: return value 1 means we should stop walking down.
f82d02d9 4580 */
2c47e605 4581static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
5d4f98a2 4582 struct btrfs_root *root,
2c47e605
YZ		 4583 struct btrfs_path *path,
4584 struct walk_control *wc)
f82d02d9 4585{
2c47e605
YZ		 4586 int level = wc->level;
4587 struct extent_buffer *eb = path->nodes[level];
4588 struct btrfs_key key;
4589 u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF;
f82d02d9
YZ		 4590 int ret;
4591
2c47e605
YZ		 4592 if (wc->stage == UPDATE_BACKREF &&
4593 btrfs_header_owner(eb) != root->root_key.objectid)
4594 return 1;
f82d02d9 4595
2c47e605
YZ		 4596 /*
4597 * when reference count of tree block is 1, it won't increase
4598 * again. once full backref flag is set, we never clear it.
4599 */
4600 if ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
4601 (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag))) {
4602 BUG_ON(!path->locks[level]);
4603 ret = btrfs_lookup_extent_info(trans, root,
4604 eb->start, eb->len,
4605 &wc->refs[level],
4606 &wc->flags[level]);
4607 BUG_ON(ret);
4608 BUG_ON(wc->refs[level] == 0);
4609 }
5d4f98a2 4610
2c47e605
YZ		 4611 if (wc->stage == DROP_REFERENCE &&
4612 wc->update_ref && wc->refs[level] > 1) {
4613 BUG_ON(eb == root->node);
4614 BUG_ON(path->slots[level] > 0);
4615 if (level == 0)
4616 btrfs_item_key_to_cpu(eb, &key, path->slots[level]);
4617 else
4618 btrfs_node_key_to_cpu(eb, &key, path->slots[level]);
4619 if (btrfs_header_owner(eb) == root->root_key.objectid &&
4620 btrfs_comp_cpu_keys(&key, &wc->update_progress) >= 0) {
4621 wc->stage = UPDATE_BACKREF;
4622 wc->shared_level = level;
f82d02d9 4623 }
2c47e605 4624 }
f82d02d9 4625
2c47e605
YZ		 4626 if (wc->stage == DROP_REFERENCE) {
4627 if (wc->refs[level] > 1)
4628 return 1;
f82d02d9 4629
2c47e605
YZ		 4630 if (path->locks[level] && !wc->keep_locks) {
4631 btrfs_tree_unlock(eb);
4632 path->locks[level] = 0;
4633 }
4634 return 0;
4635 }
f82d02d9 4636
2c47e605
YZ		 4637 /* wc->stage == UPDATE_BACKREF */
4638 if (!(wc->flags[level] & flag)) {
4639 BUG_ON(!path->locks[level]);
4640 ret = btrfs_inc_ref(trans, root, eb, 1);
f82d02d9 4641 BUG_ON(ret);
2c47e605
YZ		 4642 ret = btrfs_dec_ref(trans, root, eb, 0);
4643 BUG_ON(ret);
4644 ret = btrfs_set_disk_extent_flags(trans, root, eb->start,
4645 eb->len, flag, 0);
4646 BUG_ON(ret);
4647 wc->flags[level] |= flag;
4648 }
4649
4650 /*
4651 * the block is shared by multiple trees, so it's not good to
4652 * keep the tree lock
4653 */
4654 if (path->locks[level] && level > 0) {
4655 btrfs_tree_unlock(eb);
4656 path->locks[level] = 0;
4657 }
4658 return 0;
4659}
4660
4661/*
4662 * hepler to process tree block while walking up the tree.
4663 *
4664 * when wc->stage == DROP_REFERENCE, this function drops
4665 * reference count on the block.
4666 *
4667 * when wc->stage == UPDATE_BACKREF, this function changes
4668 * wc->stage back to DROP_REFERENCE if we changed wc->stage
4669 * to UPDATE_BACKREF previously while processing the block.
4670 *
4671 * NOTE: return value 1 means we should stop walking up.
4672 */
4673static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
4674 struct btrfs_root *root,
4675 struct btrfs_path *path,
4676 struct walk_control *wc)
4677{
4678 int ret = 0;
4679 int level = wc->level;
4680 struct extent_buffer *eb = path->nodes[level];
4681 u64 parent = 0;
4682
4683 if (wc->stage == UPDATE_BACKREF) {
4684 BUG_ON(wc->shared_level < level);
4685 if (level < wc->shared_level)
4686 goto out;
4687
4688 BUG_ON(wc->refs[level] <= 1);
4689 ret = find_next_key(path, level + 1, &wc->update_progress);
4690 if (ret > 0)
4691 wc->update_ref = 0;
4692
4693 wc->stage = DROP_REFERENCE;
4694 wc->shared_level = -1;
4695 path->slots[level] = 0;
4696
4697 /*
4698 * check reference count again if the block isn't locked.
4699 * we should start walking down the tree again if reference
4700 * count is one.
4701 */
4702 if (!path->locks[level]) {
4703 BUG_ON(level == 0);
4704 btrfs_tree_lock(eb);
4705 btrfs_set_lock_blocking(eb);
4706 path->locks[level] = 1;
4707
4708 ret = btrfs_lookup_extent_info(trans, root,
4709 eb->start, eb->len,
4710 &wc->refs[level],
4711 &wc->flags[level]);
f82d02d9 4712 BUG_ON(ret);
2c47e605
YZ		 4713 BUG_ON(wc->refs[level] == 0);
4714 if (wc->refs[level] == 1) {
4715 btrfs_tree_unlock(eb);
4716 path->locks[level] = 0;
4717 return 1;
4718 }
4719 } else {
4720 BUG_ON(level != 0);
f82d02d9 4721 }
2c47e605 4722 }
f82d02d9 4723
2c47e605
YZ		 4724 /* wc->stage == DROP_REFERENCE */
4725 BUG_ON(wc->refs[level] > 1 && !path->locks[level]);
5d4f98a2 4726
2c47e605
YZ		 4727 if (wc->refs[level] == 1) {
4728 if (level == 0) {
4729 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
4730 ret = btrfs_dec_ref(trans, root, eb, 1);
4731 else
4732 ret = btrfs_dec_ref(trans, root, eb, 0);
4733 BUG_ON(ret);
4734 }
4735 /* make block locked assertion in clean_tree_block happy */
4736 if (!path->locks[level] &&
4737 btrfs_header_generation(eb) == trans->transid) {
4738 btrfs_tree_lock(eb);
4739 btrfs_set_lock_blocking(eb);
4740 path->locks[level] = 1;
4741 }
4742 clean_tree_block(trans, root, eb);
4743 }
4744
4745 if (eb == root->node) {
4746 if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
4747 parent = eb->start;
4748 else
4749 BUG_ON(root->root_key.objectid !=
4750 btrfs_header_owner(eb));
4751 } else {
4752 if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF)
4753 parent = path->nodes[level + 1]->start;
4754 else
4755 BUG_ON(root->root_key.objectid !=
4756 btrfs_header_owner(path->nodes[level + 1]));
f82d02d9 4757 }
f82d02d9 4758
2c47e605
YZ		 4759 ret = btrfs_free_extent(trans, root, eb->start, eb->len, parent,
4760 root->root_key.objectid, level, 0);
f82d02d9 4761 BUG_ON(ret);
2c47e605
YZ		 4762out:
4763 wc->refs[level] = 0;
4764 wc->flags[level] = 0;
4765 return ret;
4766}
4767
4768static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
4769 struct btrfs_root *root,
4770 struct btrfs_path *path,
4771 struct walk_control *wc)
4772{
4773 struct extent_buffer *next;
4774 struct extent_buffer *cur;
4775 u64 bytenr;
4776 u64 ptr_gen;
4777 u32 blocksize;
4778 int level = wc->level;
4779 int ret;
4780
4781 while (level >= 0) {
4782 cur = path->nodes[level];
4783 BUG_ON(path->slots[level] >= btrfs_header_nritems(cur));
f82d02d9 4784
2c47e605
YZ		 4785 ret = walk_down_proc(trans, root, path, wc);
4786 if (ret > 0)
4787 break;
4788
4789 if (level == 0)
4790 break;
4791
4792 bytenr = btrfs_node_blockptr(cur, path->slots[level]);
4793 blocksize = btrfs_level_size(root, level - 1);
4794 ptr_gen = btrfs_node_ptr_generation(cur, path->slots[level]);
4795
4796 next = read_tree_block(root, bytenr, blocksize, ptr_gen);
4797 btrfs_tree_lock(next);
4798 btrfs_set_lock_blocking(next);
4799
4800 level--;
4801 BUG_ON(level != btrfs_header_level(next));
4802 path->nodes[level] = next;
4803 path->slots[level] = 0;
4804 path->locks[level] = 1;
4805 wc->level = level;
f82d02d9 4806 }
f82d02d9
YZ		 4807 return 0;
4808}
4809
d397712b 4810static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
98ed5174 4811 struct btrfs_root *root,
f82d02d9 4812 struct btrfs_path *path,
2c47e605 4813 struct walk_control *wc, int max_level)
20524f02 4814{
2c47e605 4815 int level = wc->level;
20524f02 4816 int ret;
9f3a7427 4817
2c47e605
YZ		 4818 path->slots[level] = btrfs_header_nritems(path->nodes[level]);
4819 while (level < max_level && path->nodes[level]) {
4820 wc->level = level;
4821 if (path->slots[level] + 1 <
4822 btrfs_header_nritems(path->nodes[level])) {
4823 path->slots[level]++;
20524f02
CM		 4824 return 0;
4825 } else {
2c47e605
YZ		 4826 ret = walk_up_proc(trans, root, path, wc);
4827 if (ret > 0)
4828 return 0;
bd56b302 4829
2c47e605
YZ		 4830 if (path->locks[level]) {
4831 btrfs_tree_unlock(path->nodes[level]);
4832 path->locks[level] = 0;
f82d02d9 4833 }
2c47e605
YZ		 4834 free_extent_buffer(path->nodes[level]);
4835 path->nodes[level] = NULL;
4836 level++;
20524f02
CM		 4837 }
4838 }
4839 return 1;
4840}
4841
9aca1d51 4842/*
2c47e605
YZ		 4843 * drop a subvolume tree.
4844 *
4845 * this function traverses the tree freeing any blocks that only
4846 * referenced by the tree.
4847 *
4848 * when a shared tree block is found. this function decreases its
4849 * reference count by one. if update_ref is true, this function
4850 * also make sure backrefs for the shared block and all lower level
4851 * blocks are properly updated.
9aca1d51 4852 */
2c47e605 4853int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref)
20524f02 4854{
5caf2a00 4855 struct btrfs_path *path;
2c47e605
YZ		 4856 struct btrfs_trans_handle *trans;
4857 struct btrfs_root *tree_root = root->fs_info->tree_root;
9f3a7427 4858 struct btrfs_root_item *root_item = &root->root_item;
2c47e605
YZ		 4859 struct walk_control *wc;
4860 struct btrfs_key key;
4861 int err = 0;
4862 int ret;
4863 int level;
20524f02 4864
5caf2a00
CM		 4865 path = btrfs_alloc_path();
4866 BUG_ON(!path);
20524f02 4867
2c47e605
YZ		 4868 wc = kzalloc(sizeof(*wc), GFP_NOFS);
4869 BUG_ON(!wc);
4870
4871 trans = btrfs_start_transaction(tree_root, 1);
4872
9f3a7427 4873 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
2c47e605 4874 level = btrfs_header_level(root->node);
5d4f98a2
YZ		 4875 path->nodes[level] = btrfs_lock_root_node(root);
4876 btrfs_set_lock_blocking(path->nodes[level]);
9f3a7427 4877 path->slots[level] = 0;
5d4f98a2 4878 path->locks[level] = 1;
2c47e605
YZ		 4879 memset(&wc->update_progress, 0,
4880 sizeof(wc->update_progress));
9f3a7427 4881 } else {
9f3a7427 4882 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
2c47e605
YZ		 4883 memcpy(&wc->update_progress, &key,
4884 sizeof(wc->update_progress));
4885
6702ed49 4886 level = root_item->drop_level;
2c47e605 4887 BUG_ON(level == 0);
6702ed49 4888 path->lowest_level = level;
2c47e605
YZ		 4889 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4890 path->lowest_level = 0;
4891 if (ret < 0) {
4892 err = ret;
9f3a7427
CM		 4893 goto out;
4894 }
2c47e605
YZ		 4895 btrfs_node_key_to_cpu(path->nodes[level], &key,
4896 path->slots[level]);
4897 WARN_ON(memcmp(&key, &wc->update_progress, sizeof(key)));
4898
7d9eb12c
CM		 4899 /*
4900 * unlock our path, this is safe because only this
4901 * function is allowed to delete this snapshot
4902 */
5d4f98a2 4903 btrfs_unlock_up_safe(path, 0);
2c47e605
YZ		 4904
4905 level = btrfs_header_level(root->node);
4906 while (1) {
4907 btrfs_tree_lock(path->nodes[level]);
4908 btrfs_set_lock_blocking(path->nodes[level]);
4909
4910 ret = btrfs_lookup_extent_info(trans, root,
4911 path->nodes[level]->start,
4912 path->nodes[level]->len,
4913 &wc->refs[level],
4914 &wc->flags[level]);
4915 BUG_ON(ret);
4916 BUG_ON(wc->refs[level] == 0);
4917
4918 if (level == root_item->drop_level)
4919 break;
4920
4921 btrfs_tree_unlock(path->nodes[level]);
4922 WARN_ON(wc->refs[level] != 1);
4923 level--;
4924 }
9f3a7427 4925 }
2c47e605
YZ		 4926
4927 wc->level = level;
4928 wc->shared_level = -1;
4929 wc->stage = DROP_REFERENCE;
4930 wc->update_ref = update_ref;
4931 wc->keep_locks = 0;
4932
d397712b 4933 while (1) {
2c47e605
YZ		 4934 ret = walk_down_tree(trans, root, path, wc);
4935 if (ret < 0) {
4936 err = ret;
20524f02 4937 break;
2c47e605 4938 }
9aca1d51 4939
2c47e605
YZ		 4940 ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL);
4941 if (ret < 0) {
4942 err = ret;
20524f02 4943 break;
2c47e605
YZ		 4944 }
4945
4946 if (ret > 0) {
4947 BUG_ON(wc->stage != DROP_REFERENCE);
e7a84565
CM		 4948 break;
4949 }
2c47e605
YZ		 4950
4951 if (wc->stage == DROP_REFERENCE) {
4952 level = wc->level;
4953 btrfs_node_key(path->nodes[level],
4954 &root_item->drop_progress,
4955 path->slots[level]);
4956 root_item->drop_level = level;
4957 }
4958
4959 BUG_ON(wc->level == 0);
4960 if (trans->transaction->in_commit ||
4961 trans->transaction->delayed_refs.flushing) {
4962 ret = btrfs_update_root(trans, tree_root,
4963 &root->root_key,
4964 root_item);
4965 BUG_ON(ret);
4966
4967 btrfs_end_transaction(trans, tree_root);
4968 trans = btrfs_start_transaction(tree_root, 1);
4969 } else {
4970 unsigned long update;
c3e69d58
CM		 4971 update = trans->delayed_ref_updates;
4972 trans->delayed_ref_updates = 0;
4973 if (update)
2c47e605
YZ		 4974 btrfs_run_delayed_refs(trans, tree_root,
4975 update);
c3e69d58 4976 }
20524f02 4977 }
2c47e605
YZ		 4978 btrfs_release_path(root, path);
4979 BUG_ON(err);
4980
4981 ret = btrfs_del_root(trans, tree_root, &root->root_key);
4982 BUG_ON(ret);
4983
4984 free_extent_buffer(root->node);
4985 free_extent_buffer(root->commit_root);
4986 kfree(root);
9f3a7427 4987out:
2c47e605
YZ		 4988 btrfs_end_transaction(trans, tree_root);
4989 kfree(wc);
5caf2a00 4990 btrfs_free_path(path);
2c47e605 4991 return err;
20524f02 4992}
9078a3e1 4993
2c47e605
YZ		 4994/*
4995 * drop subtree rooted at tree block 'node'.
4996 *
4997 * NOTE: this function will unlock and release tree block 'node'
4998 */
f82d02d9
YZ		 4999int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
5000 struct btrfs_root *root,
5001 struct extent_buffer *node,
5002 struct extent_buffer *parent)
5003{
5004 struct btrfs_path *path;
2c47e605 5005 struct walk_control *wc;
f82d02d9
YZ		 5006 int level;
5007 int parent_level;
5008 int ret = 0;
5009 int wret;
5010
2c47e605
YZ		 5011 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
5012
f82d02d9
YZ		 5013 path = btrfs_alloc_path();
5014 BUG_ON(!path);
5015
2c47e605
YZ		 5016 wc = kzalloc(sizeof(*wc), GFP_NOFS);
5017 BUG_ON(!wc);
5018
b9447ef8 5019 btrfs_assert_tree_locked(parent);
f82d02d9
YZ		 5020 parent_level = btrfs_header_level(parent);
5021 extent_buffer_get(parent);
5022 path->nodes[parent_level] = parent;
5023 path->slots[parent_level] = btrfs_header_nritems(parent);
5024
b9447ef8 5025 btrfs_assert_tree_locked(node);
f82d02d9 5026 level = btrfs_header_level(node);
f82d02d9
YZ		 5027 path->nodes[level] = node;
5028 path->slots[level] = 0;
2c47e605
YZ		 5029 path->locks[level] = 1;
5030
5031 wc->refs[parent_level] = 1;
5032 wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF;
5033 wc->level = level;
5034 wc->shared_level = -1;
5035 wc->stage = DROP_REFERENCE;
5036 wc->update_ref = 0;
5037 wc->keep_locks = 1;
f82d02d9
YZ		 5038
5039 while (1) {
2c47e605
YZ		 5040 wret = walk_down_tree(trans, root, path, wc);
5041 if (wret < 0) {
f82d02d9 5042 ret = wret;
f82d02d9 5043 break;
2c47e605 5044 }
f82d02d9 5045
2c47e605 5046 wret = walk_up_tree(trans, root, path, wc, parent_level);
f82d02d9
YZ		 5047 if (wret < 0)
5048 ret = wret;
5049 if (wret != 0)
5050 break;
5051 }
5052
2c47e605 5053 kfree(wc);
f82d02d9
YZ		 5054 btrfs_free_path(path);
5055 return ret;
5056}
5057
5d4f98a2 5058#if 0
8e7bf94f
CM		 5059static unsigned long calc_ra(unsigned long start, unsigned long last,
5060 unsigned long nr)
5061{
5062 return min(last, start + nr - 1);
5063}
5064
d397712b 5065static noinline int relocate_inode_pages(struct inode *inode, u64 start,
98ed5174 5066 u64 len)
edbd8d4e
CM		 5067{
5068 u64 page_start;
5069 u64 page_end;
1a40e23b 5070 unsigned long first_index;
edbd8d4e 5071 unsigned long last_index;
edbd8d4e
CM		 5072 unsigned long i;
5073 struct page *page;
d1310b2e 5074 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4313b399 5075 struct file_ra_state *ra;
3eaa2885 5076 struct btrfs_ordered_extent *ordered;
1a40e23b
ZY		 5077 unsigned int total_read = 0;
5078 unsigned int total_dirty = 0;
5079 int ret = 0;
4313b399
CM		 5080
5081 ra = kzalloc(sizeof(*ra), GFP_NOFS);
edbd8d4e
CM		 5082
5083 mutex_lock(&inode->i_mutex);
1a40e23b 5084 first_index = start >> PAGE_CACHE_SHIFT;
edbd8d4e
CM		 5085 last_index = (start + len - 1) >> PAGE_CACHE_SHIFT;
5086
1a40e23b
ZY		 5087 /* make sure the dirty trick played by the caller work */
5088 ret = invalidate_inode_pages2_range(inode->i_mapping,
5089 first_index, last_index);
5090 if (ret)
5091 goto out_unlock;
8e7bf94f 5092
4313b399 5093 file_ra_state_init(ra, inode->i_mapping);
edbd8d4e 5094
1a40e23b
ZY		 5095 for (i = first_index ; i <= last_index; i++) {
5096 if (total_read % ra->ra_pages == 0) {
8e7bf94f 5097 btrfs_force_ra(inode->i_mapping, ra, NULL, i,
1a40e23b 5098 calc_ra(i, last_index, ra->ra_pages));
8e7bf94f
CM		 5099 }
5100 total_read++;
3eaa2885
CM		 5101again:
5102 if (((u64)i << PAGE_CACHE_SHIFT) > i_size_read(inode))
1a40e23b 5103 BUG_ON(1);
edbd8d4e 5104 page = grab_cache_page(inode->i_mapping, i);
a061fc8d 5105 if (!page) {
1a40e23b 5106 ret = -ENOMEM;
edbd8d4e 5107 goto out_unlock;
a061fc8d 5108 }
edbd8d4e
CM		 5109 if (!PageUptodate(page)) {
5110 btrfs_readpage(NULL, page);
5111 lock_page(page);
5112 if (!PageUptodate(page)) {
5113 unlock_page(page);
5114 page_cache_release(page);
1a40e23b 5115 ret = -EIO;
edbd8d4e
CM		 5116 goto out_unlock;
5117 }
5118 }
ec44a35c 5119 wait_on_page_writeback(page);
3eaa2885 5120
edbd8d4e
CM		 5121 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
5122 page_end = page_start + PAGE_CACHE_SIZE - 1;
d1310b2e 5123 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
edbd8d4e 5124
3eaa2885
CM		 5125 ordered = btrfs_lookup_ordered_extent(inode, page_start);
5126 if (ordered) {
5127 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
5128 unlock_page(page);
5129 page_cache_release(page);
5130 btrfs_start_ordered_extent(inode, ordered, 1);
5131 btrfs_put_ordered_extent(ordered);
5132 goto again;
5133 }
5134 set_page_extent_mapped(page);
5135
1a40e23b
ZY		 5136 if (i == first_index)
5137 set_extent_bits(io_tree, page_start, page_end,
5138 EXTENT_BOUNDARY, GFP_NOFS);
1f80e4db 5139 btrfs_set_extent_delalloc(inode, page_start, page_end);
1a40e23b 5140
a061fc8d 5141 set_page_dirty(page);
1a40e23b 5142 total_dirty++;
edbd8d4e 5143
d1310b2e 5144 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
edbd8d4e
CM		 5145 unlock_page(page);
5146 page_cache_release(page);
5147 }
5148
5149out_unlock:
ec44a35c 5150 kfree(ra);
edbd8d4e 5151 mutex_unlock(&inode->i_mutex);
1a40e23b
ZY		 5152 balance_dirty_pages_ratelimited_nr(inode->i_mapping, total_dirty);
5153 return ret;
edbd8d4e
CM		 5154}
5155
d397712b 5156static noinline int relocate_data_extent(struct inode *reloc_inode,
1a40e23b
ZY		 5157 struct btrfs_key *extent_key,
5158 u64 offset)
5159{
5160 struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
5161 struct extent_map_tree *em_tree = &BTRFS_I(reloc_inode)->extent_tree;
5162 struct extent_map *em;
6643558d
YZ		 5163 u64 start = extent_key->objectid - offset;
5164 u64 end = start + extent_key->offset - 1;
bf4ef679 5165
1a40e23b
ZY		 5166 em = alloc_extent_map(GFP_NOFS);
5167 BUG_ON(!em || IS_ERR(em));
bf4ef679 5168
6643558d 5169 em->start = start;
1a40e23b 5170 em->len = extent_key->offset;
c8b97818 5171 em->block_len = extent_key->offset;
1a40e23b
ZY		 5172 em->block_start = extent_key->objectid;
5173 em->bdev = root->fs_info->fs_devices->latest_bdev;
5174 set_bit(EXTENT_FLAG_PINNED, &em->flags);
5175
5176 /* setup extent map to cheat btrfs_readpage */
6643558d 5177 lock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
1a40e23b
ZY		 5178 while (1) {
5179 int ret;
5180 spin_lock(&em_tree->lock);
5181 ret = add_extent_mapping(em_tree, em);
5182 spin_unlock(&em_tree->lock);
5183 if (ret != -EEXIST) {
5184 free_extent_map(em);
bf4ef679
CM		 5185 break;
5186 }
6643558d 5187 btrfs_drop_extent_cache(reloc_inode, start, end, 0);
bf4ef679 5188 }
6643558d 5189 unlock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
bf4ef679 5190
6643558d 5191 return relocate_inode_pages(reloc_inode, start, extent_key->offset);
1a40e23b 5192}
edbd8d4e 5193
1a40e23b
ZY		 5194struct btrfs_ref_path {
5195 u64 extent_start;
5196 u64 nodes[BTRFS_MAX_LEVEL];
5197 u64 root_objectid;
5198 u64 root_generation;
5199 u64 owner_objectid;
1a40e23b
ZY		 5200 u32 num_refs;
5201 int lowest_level;
5202 int current_level;
f82d02d9
YZ		 5203 int shared_level;
5204
5205 struct btrfs_key node_keys[BTRFS_MAX_LEVEL];
5206 u64 new_nodes[BTRFS_MAX_LEVEL];
1a40e23b 5207};
7d9eb12c 5208
1a40e23b 5209struct disk_extent {
c8b97818 5210 u64 ram_bytes;
1a40e23b
ZY		 5211 u64 disk_bytenr;
5212 u64 disk_num_bytes;
5213 u64 offset;
5214 u64 num_bytes;
c8b97818
CM		 5215 u8 compression;
5216 u8 encryption;
5217 u16 other_encoding;
1a40e23b 5218};
4313b399 5219
1a40e23b
ZY		 5220static int is_cowonly_root(u64 root_objectid)
5221{
5222 if (root_objectid == BTRFS_ROOT_TREE_OBJECTID ||
5223 root_objectid == BTRFS_EXTENT_TREE_OBJECTID ||
5224 root_objectid == BTRFS_CHUNK_TREE_OBJECTID ||
5225 root_objectid == BTRFS_DEV_TREE_OBJECTID ||
0403e47e
YZ		 5226 root_objectid == BTRFS_TREE_LOG_OBJECTID ||
5227 root_objectid == BTRFS_CSUM_TREE_OBJECTID)
1a40e23b
ZY		 5228 return 1;
5229 return 0;
5230}
edbd8d4e 5231
d397712b 5232static noinline int __next_ref_path(struct btrfs_trans_handle *trans,
1a40e23b
ZY		 5233 struct btrfs_root *extent_root,
5234 struct btrfs_ref_path *ref_path,
5235 int first_time)
5236{
5237 struct extent_buffer *leaf;
5238 struct btrfs_path *path;
5239 struct btrfs_extent_ref *ref;
5240 struct btrfs_key key;
5241 struct btrfs_key found_key;
5242 u64 bytenr;
5243 u32 nritems;
5244 int level;
5245 int ret = 1;
edbd8d4e 5246
1a40e23b
ZY		 5247 path = btrfs_alloc_path();
5248 if (!path)
5249 return -ENOMEM;
bf4ef679 5250
1a40e23b
ZY		 5251 if (first_time) {
5252 ref_path->lowest_level = -1;
5253 ref_path->current_level = -1;
f82d02d9 5254 ref_path->shared_level = -1;
1a40e23b
ZY		 5255 goto walk_up;
5256 }
5257walk_down:
5258 level = ref_path->current_level - 1;
5259 while (level >= -1) {
5260 u64 parent;
5261 if (level < ref_path->lowest_level)
5262 break;
bf4ef679 5263
d397712b 5264 if (level >= 0)
1a40e23b 5265 bytenr = ref_path->nodes[level];
d397712b 5266 else
1a40e23b 5267 bytenr = ref_path->extent_start;
1a40e23b 5268 BUG_ON(bytenr == 0);
bf4ef679 5269
1a40e23b
ZY		 5270 parent = ref_path->nodes[level + 1];
5271 ref_path->nodes[level + 1] = 0;
5272 ref_path->current_level = level;
5273 BUG_ON(parent == 0);
0ef3e66b 5274
1a40e23b
ZY		 5275 key.objectid = bytenr;
5276 key.offset = parent + 1;
5277 key.type = BTRFS_EXTENT_REF_KEY;
edbd8d4e 5278
1a40e23b
ZY		 5279 ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0);
5280 if (ret < 0)
edbd8d4e 5281 goto out;
1a40e23b 5282 BUG_ON(ret == 0);
7d9eb12c 5283
1a40e23b
ZY		 5284 leaf = path->nodes[0];
5285 nritems = btrfs_header_nritems(leaf);
5286 if (path->slots[0] >= nritems) {
5287 ret = btrfs_next_leaf(extent_root, path);
5288 if (ret < 0)
5289 goto out;
5290 if (ret > 0)
5291 goto next;
5292 leaf = path->nodes[0];
5293 }
0ef3e66b 5294
1a40e23b
ZY		 5295 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5296 if (found_key.objectid == bytenr &&
f82d02d9
YZ		 5297 found_key.type == BTRFS_EXTENT_REF_KEY) {
5298 if (level < ref_path->shared_level)
5299 ref_path->shared_level = level;
1a40e23b 5300 goto found;
f82d02d9 5301 }
1a40e23b
ZY		 5302next:
5303 level--;
5304 btrfs_release_path(extent_root, path);
d899e052 5305 cond_resched();
1a40e23b
ZY		 5306 }
5307 /* reached lowest level */
5308 ret = 1;
5309 goto out;
5310walk_up:
5311 level = ref_path->current_level;
5312 while (level < BTRFS_MAX_LEVEL - 1) {
5313 u64 ref_objectid;
d397712b
CM		 5314
5315 if (level >= 0)
1a40e23b 5316 bytenr = ref_path->nodes[level];
d397712b 5317 else
1a40e23b 5318 bytenr = ref_path->extent_start;
d397712b 5319
1a40e23b 5320 BUG_ON(bytenr == 0);
edbd8d4e 5321
1a40e23b
ZY		 5322 key.objectid = bytenr;
5323 key.offset = 0;
5324 key.type = BTRFS_EXTENT_REF_KEY;
edbd8d4e 5325
1a40e23b
ZY		 5326 ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0);
5327 if (ret < 0)
5328 goto out;
edbd8d4e 5329
1a40e23b
ZY		 5330 leaf = path->nodes[0];
5331 nritems = btrfs_header_nritems(leaf);
5332 if (path->slots[0] >= nritems) {
5333 ret = btrfs_next_leaf(extent_root, path);
5334 if (ret < 0)
5335 goto out;
5336 if (ret > 0) {
5337 /* the extent was freed by someone */
5338 if (ref_path->lowest_level == level)
5339 goto out;
5340 btrfs_release_path(extent_root, path);
5341 goto walk_down;
5342 }
5343 leaf = path->nodes[0];
5344 }
edbd8d4e 5345
1a40e23b
ZY		 5346 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5347 if (found_key.objectid != bytenr ||
5348 found_key.type != BTRFS_EXTENT_REF_KEY) {
5349 /* the extent was freed by someone */
5350 if (ref_path->lowest_level == level) {
5351 ret = 1;
5352 goto out;
5353 }
5354 btrfs_release_path(extent_root, path);
5355 goto walk_down;
5356 }
5357found:
5358 ref = btrfs_item_ptr(leaf, path->slots[0],
5359 struct btrfs_extent_ref);
5360 ref_objectid = btrfs_ref_objectid(leaf, ref);
5361 if (ref_objectid < BTRFS_FIRST_FREE_OBJECTID) {
5362 if (first_time) {
5363 level = (int)ref_objectid;
5364 BUG_ON(level >= BTRFS_MAX_LEVEL);
5365 ref_path->lowest_level = level;
5366 ref_path->current_level = level;
5367 ref_path->nodes[level] = bytenr;
5368 } else {
5369 WARN_ON(ref_objectid != level);
5370 }
5371 } else {
5372 WARN_ON(level != -1);
5373 }
5374 first_time = 0;
bf4ef679 5375
1a40e23b
ZY		 5376 if (ref_path->lowest_level == level) {
5377 ref_path->owner_objectid = ref_objectid;
1a40e23b
ZY		 5378 ref_path->num_refs = btrfs_ref_num_refs(leaf, ref);
5379 }
bf4ef679 5380
7d9eb12c 5381 /*
1a40e23b
ZY		 5382 * the block is tree root or the block isn't in reference
5383 * counted tree.
7d9eb12c 5384 */
1a40e23b
ZY		 5385 if (found_key.objectid == found_key.offset ||
5386 is_cowonly_root(btrfs_ref_root(leaf, ref))) {
5387 ref_path->root_objectid = btrfs_ref_root(leaf, ref);
5388 ref_path->root_generation =
5389 btrfs_ref_generation(leaf, ref);
5390 if (level < 0) {
5391 /* special reference from the tree log */
5392 ref_path->nodes[0] = found_key.offset;
5393 ref_path->current_level = 0;
5394 }
5395 ret = 0;
5396 goto out;
5397 }
7d9eb12c 5398
1a40e23b
ZY		 5399 level++;
5400 BUG_ON(ref_path->nodes[level] != 0);
5401 ref_path->nodes[level] = found_key.offset;
5402 ref_path->current_level = level;
bf4ef679 5403
1a40e23b
ZY		 5404 /*
5405 * the reference was created in the running transaction,
5406 * no need to continue walking up.
5407 */
5408 if (btrfs_ref_generation(leaf, ref) == trans->transid) {
5409 ref_path->root_objectid = btrfs_ref_root(leaf, ref);
5410 ref_path->root_generation =
5411 btrfs_ref_generation(leaf, ref);
5412 ret = 0;
5413 goto out;
7d9eb12c
CM		 5414 }
5415
1a40e23b 5416 btrfs_release_path(extent_root, path);
d899e052 5417 cond_resched();
7d9eb12c 5418 }
1a40e23b
ZY		 5419 /* reached max tree level, but no tree root found. */
5420 BUG();
edbd8d4e 5421out:
1a40e23b
ZY		 5422 btrfs_free_path(path);
5423 return ret;
edbd8d4e
CM		 5424}
5425
1a40e23b
ZY		 5426static int btrfs_first_ref_path(struct btrfs_trans_handle *trans,
5427 struct btrfs_root *extent_root,
5428 struct btrfs_ref_path *ref_path,
5429 u64 extent_start)
a061fc8d 5430{
1a40e23b
ZY		 5431 memset(ref_path, 0, sizeof(*ref_path));
5432 ref_path->extent_start = extent_start;
a061fc8d 5433
1a40e23b 5434 return __next_ref_path(trans, extent_root, ref_path, 1);
a061fc8d
CM		 5435}
5436
1a40e23b
ZY		 5437static int btrfs_next_ref_path(struct btrfs_trans_handle *trans,
5438 struct btrfs_root *extent_root,
5439 struct btrfs_ref_path *ref_path)
edbd8d4e 5440{
1a40e23b
ZY		 5441 return __next_ref_path(trans, extent_root, ref_path, 0);
5442}
5443
d397712b 5444static noinline int get_new_locations(struct inode *reloc_inode,
1a40e23b
ZY		 5445 struct btrfs_key *extent_key,
5446 u64 offset, int no_fragment,
5447 struct disk_extent **extents,
5448 int *nr_extents)
5449{
5450 struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
5451 struct btrfs_path *path;
5452 struct btrfs_file_extent_item *fi;
edbd8d4e 5453 struct extent_buffer *leaf;
1a40e23b
ZY		 5454 struct disk_extent *exts = *extents;
5455 struct btrfs_key found_key;
5456 u64 cur_pos;
5457 u64 last_byte;
edbd8d4e 5458 u32 nritems;
1a40e23b
ZY		 5459 int nr = 0;
5460 int max = *nr_extents;
5461 int ret;
edbd8d4e 5462
1a40e23b
ZY		 5463 WARN_ON(!no_fragment && *extents);
5464 if (!exts) {
5465 max = 1;
5466 exts = kmalloc(sizeof(*exts) * max, GFP_NOFS);
5467 if (!exts)
5468 return -ENOMEM;
a061fc8d 5469 }
edbd8d4e 5470
1a40e23b
ZY		 5471 path = btrfs_alloc_path();
5472 BUG_ON(!path);
edbd8d4e 5473
1a40e23b
ZY		 5474 cur_pos = extent_key->objectid - offset;
5475 last_byte = extent_key->objectid + extent_key->offset;
5476 ret = btrfs_lookup_file_extent(NULL, root, path, reloc_inode->i_ino,
5477 cur_pos, 0);
5478 if (ret < 0)
5479 goto out;
5480 if (ret > 0) {
5481 ret = -ENOENT;
5482 goto out;
5483 }
edbd8d4e 5484
1a40e23b 5485 while (1) {
edbd8d4e
CM		 5486 leaf = path->nodes[0];
5487 nritems = btrfs_header_nritems(leaf);
1a40e23b
ZY		 5488 if (path->slots[0] >= nritems) {
5489 ret = btrfs_next_leaf(root, path);
a061fc8d
CM		 5490 if (ret < 0)
5491 goto out;
1a40e23b
ZY		 5492 if (ret > 0)
5493 break;
bf4ef679 5494 leaf = path->nodes[0];
a061fc8d 5495 }
edbd8d4e
CM		 5496
5497 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1a40e23b
ZY		 5498 if (found_key.offset != cur_pos ||
5499 found_key.type != BTRFS_EXTENT_DATA_KEY ||
5500 found_key.objectid != reloc_inode->i_ino)
edbd8d4e
CM		 5501 break;
5502
1a40e23b
ZY		 5503 fi = btrfs_item_ptr(leaf, path->slots[0],
5504 struct btrfs_file_extent_item);
5505 if (btrfs_file_extent_type(leaf, fi) !=
5506 BTRFS_FILE_EXTENT_REG ||
5507 btrfs_file_extent_disk_bytenr(leaf, fi) == 0)
edbd8d4e 5508 break;
1a40e23b
ZY		 5509
5510 if (nr == max) {
5511 struct disk_extent *old = exts;
5512 max *= 2;
5513 exts = kzalloc(sizeof(*exts) * max, GFP_NOFS);
5514 memcpy(exts, old, sizeof(*exts) * nr);
5515 if (old != *extents)
5516 kfree(old);
a061fc8d 5517 }
edbd8d4e 5518
1a40e23b
ZY		 5519 exts[nr].disk_bytenr =
5520 btrfs_file_extent_disk_bytenr(leaf, fi);
5521 exts[nr].disk_num_bytes =
5522 btrfs_file_extent_disk_num_bytes(leaf, fi);
5523 exts[nr].offset = btrfs_file_extent_offset(leaf, fi);
5524 exts[nr].num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
c8b97818
CM		 5525 exts[nr].ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
5526 exts[nr].compression = btrfs_file_extent_compression(leaf, fi);
5527 exts[nr].encryption = btrfs_file_extent_encryption(leaf, fi);
5528 exts[nr].other_encoding = btrfs_file_extent_other_encoding(leaf,
5529 fi);
d899e052
YZ		 5530 BUG_ON(exts[nr].offset > 0);
5531 BUG_ON(exts[nr].compression || exts[nr].encryption);
5532 BUG_ON(exts[nr].num_bytes != exts[nr].disk_num_bytes);
edbd8d4e 5533
1a40e23b
ZY		 5534 cur_pos += exts[nr].num_bytes;
5535 nr++;
5536
5537 if (cur_pos + offset >= last_byte)
5538 break;
5539
5540 if (no_fragment) {
5541 ret = 1;
edbd8d4e 5542 goto out;
1a40e23b
ZY		 5543 }
5544 path->slots[0]++;
5545 }
5546
1f80e4db 5547 BUG_ON(cur_pos + offset > last_byte);
1a40e23b
ZY		 5548 if (cur_pos + offset < last_byte) {
5549 ret = -ENOENT;
5550 goto out;
edbd8d4e
CM		 5551 }
5552 ret = 0;
5553out:
1a40e23b
ZY		 5554 btrfs_free_path(path);
5555 if (ret) {
5556 if (exts != *extents)
5557 kfree(exts);
5558 } else {
5559 *extents = exts;
5560 *nr_extents = nr;
5561 }
5562 return ret;
5563}
5564
d397712b 5565static noinline int replace_one_extent(struct btrfs_trans_handle *trans,
1a40e23b
ZY		 5566 struct btrfs_root *root,
5567 struct btrfs_path *path,
5568 struct btrfs_key *extent_key,
5569 struct btrfs_key *leaf_key,
5570 struct btrfs_ref_path *ref_path,
5571 struct disk_extent *new_extents,
5572 int nr_extents)
5573{
5574 struct extent_buffer *leaf;
5575 struct btrfs_file_extent_item *fi;
5576 struct inode *inode = NULL;
5577 struct btrfs_key key;
5578 u64 lock_start = 0;
5579 u64 lock_end = 0;
5580 u64 num_bytes;
5581 u64 ext_offset;
86288a19 5582 u64 search_end = (u64)-1;
1a40e23b 5583 u32 nritems;
3bb1a1bc 5584 int nr_scaned = 0;
1a40e23b 5585 int extent_locked = 0;
d899e052 5586 int extent_type;
1a40e23b
ZY		 5587 int ret;
5588
3bb1a1bc 5589 memcpy(&key, leaf_key, sizeof(key));
1a40e23b 5590 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) {
3bb1a1bc
YZ		 5591 if (key.objectid < ref_path->owner_objectid ||
5592 (key.objectid == ref_path->owner_objectid &&
5593 key.type < BTRFS_EXTENT_DATA_KEY)) {
5594 key.objectid = ref_path->owner_objectid;
5595 key.type = BTRFS_EXTENT_DATA_KEY;
5596 key.offset = 0;
5597 }
1a40e23b
ZY		 5598 }
5599
5600 while (1) {
5601 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
5602 if (ret < 0)
5603 goto out;
5604
5605 leaf = path->nodes[0];
5606 nritems = btrfs_header_nritems(leaf);
5607next:
5608 if (extent_locked && ret > 0) {
5609 /*
5610 * the file extent item was modified by someone
5611 * before the extent got locked.
5612 */
1a40e23b
ZY		 5613 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
5614 lock_end, GFP_NOFS);
5615 extent_locked = 0;
5616 }
5617
5618 if (path->slots[0] >= nritems) {
3bb1a1bc 5619 if (++nr_scaned > 2)
1a40e23b
ZY		 5620 break;
5621
5622 BUG_ON(extent_locked);
5623 ret = btrfs_next_leaf(root, path);
5624 if (ret < 0)
5625 goto out;
5626 if (ret > 0)
5627 break;
5628 leaf = path->nodes[0];
5629 nritems = btrfs_header_nritems(leaf);
5630 }
5631
5632 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
5633
5634 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) {
5635 if ((key.objectid > ref_path->owner_objectid) ||
5636 (key.objectid == ref_path->owner_objectid &&
5637 key.type > BTRFS_EXTENT_DATA_KEY) ||
86288a19 5638 key.offset >= search_end)
1a40e23b
ZY		 5639 break;
5640 }
5641
5642 if (inode && key.objectid != inode->i_ino) {
5643 BUG_ON(extent_locked);
5644 btrfs_release_path(root, path);
5645 mutex_unlock(&inode->i_mutex);
5646 iput(inode);
5647 inode = NULL;
5648 continue;
5649 }
5650
5651 if (key.type != BTRFS_EXTENT_DATA_KEY) {
5652 path->slots[0]++;
5653 ret = 1;
5654 goto next;
5655 }
5656 fi = btrfs_item_ptr(leaf, path->slots[0],
5657 struct btrfs_file_extent_item);
d899e052
YZ		 5658 extent_type = btrfs_file_extent_type(leaf, fi);
5659 if ((extent_type != BTRFS_FILE_EXTENT_REG &&
5660 extent_type != BTRFS_FILE_EXTENT_PREALLOC) ||
1a40e23b
ZY		 5661 (btrfs_file_extent_disk_bytenr(leaf, fi) !=
5662 extent_key->objectid)) {
5663 path->slots[0]++;
5664 ret = 1;
5665 goto next;
5666 }
5667
5668 num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
5669 ext_offset = btrfs_file_extent_offset(leaf, fi);
5670
86288a19
YZ		 5671 if (search_end == (u64)-1) {
5672 search_end = key.offset - ext_offset +
5673 btrfs_file_extent_ram_bytes(leaf, fi);
5674 }
1a40e23b
ZY		 5675
5676 if (!extent_locked) {
5677 lock_start = key.offset;
5678 lock_end = lock_start + num_bytes - 1;
5679 } else {
6643558d
YZ		 5680 if (lock_start > key.offset ||
5681 lock_end + 1 < key.offset + num_bytes) {
5682 unlock_extent(&BTRFS_I(inode)->io_tree,
5683 lock_start, lock_end, GFP_NOFS);
5684 extent_locked = 0;
5685 }
1a40e23b
ZY		 5686 }
5687
5688 if (!inode) {
5689 btrfs_release_path(root, path);
5690
5691 inode = btrfs_iget_locked(root->fs_info->sb,
5692 key.objectid, root);
5693 if (inode->i_state & I_NEW) {
5694 BTRFS_I(inode)->root = root;
5695 BTRFS_I(inode)->location.objectid =
5696 key.objectid;
5697 BTRFS_I(inode)->location.type =
5698 BTRFS_INODE_ITEM_KEY;
5699 BTRFS_I(inode)->location.offset = 0;
5700 btrfs_read_locked_inode(inode);
5701 unlock_new_inode(inode);
5702 }
5703 /*
5704 * some code call btrfs_commit_transaction while
5705 * holding the i_mutex, so we can't use mutex_lock
5706 * here.
5707 */
5708 if (is_bad_inode(inode) ||
5709 !mutex_trylock(&inode->i_mutex)) {
5710 iput(inode);
5711 inode = NULL;
5712 key.offset = (u64)-1;
5713 goto skip;
5714 }
5715 }
5716
5717 if (!extent_locked) {
5718 struct btrfs_ordered_extent *ordered;
5719
5720 btrfs_release_path(root, path);
5721
5722 lock_extent(&BTRFS_I(inode)->io_tree, lock_start,
5723 lock_end, GFP_NOFS);
5724 ordered = btrfs_lookup_first_ordered_extent(inode,
5725 lock_end);
5726 if (ordered &&
5727 ordered->file_offset <= lock_end &&
5728 ordered->file_offset + ordered->len > lock_start) {
5729 unlock_extent(&BTRFS_I(inode)->io_tree,
5730 lock_start, lock_end, GFP_NOFS);
5731 btrfs_start_ordered_extent(inode, ordered, 1);
5732 btrfs_put_ordered_extent(ordered);
5733 key.offset += num_bytes;
5734 goto skip;
5735 }
5736 if (ordered)
5737 btrfs_put_ordered_extent(ordered);
5738
1a40e23b
ZY		 5739 extent_locked = 1;
5740 continue;
5741 }
5742
5743 if (nr_extents == 1) {
5744 /* update extent pointer in place */
1a40e23b
ZY		 5745 btrfs_set_file_extent_disk_bytenr(leaf, fi,
5746 new_extents[0].disk_bytenr);
5747 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
5748 new_extents[0].disk_num_bytes);
1a40e23b
ZY		 5749 btrfs_mark_buffer_dirty(leaf);
5750
5751 btrfs_drop_extent_cache(inode, key.offset,
5752 key.offset + num_bytes - 1, 0);
5753
5754 ret = btrfs_inc_extent_ref(trans, root,
5755 new_extents[0].disk_bytenr,
5756 new_extents[0].disk_num_bytes,
5757 leaf->start,
5758 root->root_key.objectid,
5759 trans->transid,
3bb1a1bc 5760 key.objectid);
1a40e23b
ZY		 5761 BUG_ON(ret);
5762
5763 ret = btrfs_free_extent(trans, root,
5764 extent_key->objectid,
5765 extent_key->offset,
5766 leaf->start,
5767 btrfs_header_owner(leaf),
5768 btrfs_header_generation(leaf),
3bb1a1bc 5769 key.objectid, 0);
1a40e23b
ZY		 5770 BUG_ON(ret);
5771
5772 btrfs_release_path(root, path);
5773 key.offset += num_bytes;
5774 } else {
d899e052
YZ		 5775 BUG_ON(1);
5776#if 0
1a40e23b
ZY		 5777 u64 alloc_hint;
5778 u64 extent_len;
5779 int i;
5780 /*
5781 * drop old extent pointer at first, then insert the
5782 * new pointers one bye one
5783 */
5784 btrfs_release_path(root, path);
5785 ret = btrfs_drop_extents(trans, root, inode, key.offset,
5786 key.offset + num_bytes,
5787 key.offset, &alloc_hint);
5788 BUG_ON(ret);
5789
5790 for (i = 0; i < nr_extents; i++) {
5791 if (ext_offset >= new_extents[i].num_bytes) {
5792 ext_offset -= new_extents[i].num_bytes;
5793 continue;
5794 }
5795 extent_len = min(new_extents[i].num_bytes -
5796 ext_offset, num_bytes);
5797
5798 ret = btrfs_insert_empty_item(trans, root,
5799 path, &key,
5800 sizeof(*fi));
5801 BUG_ON(ret);
5802
5803 leaf = path->nodes[0];
5804 fi = btrfs_item_ptr(leaf, path->slots[0],
5805 struct btrfs_file_extent_item);
5806 btrfs_set_file_extent_generation(leaf, fi,
5807 trans->transid);
5808 btrfs_set_file_extent_type(leaf, fi,
5809 BTRFS_FILE_EXTENT_REG);
5810 btrfs_set_file_extent_disk_bytenr(leaf, fi,
5811 new_extents[i].disk_bytenr);
5812 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
5813 new_extents[i].disk_num_bytes);
c8b97818
CM		 5814 btrfs_set_file_extent_ram_bytes(leaf, fi,
5815 new_extents[i].ram_bytes);
5816
5817 btrfs_set_file_extent_compression(leaf, fi,
5818 new_extents[i].compression);
5819 btrfs_set_file_extent_encryption(leaf, fi,
5820 new_extents[i].encryption);
5821 btrfs_set_file_extent_other_encoding(leaf, fi,
5822 new_extents[i].other_encoding);
5823
1a40e23b
ZY		 5824 btrfs_set_file_extent_num_bytes(leaf, fi,
5825 extent_len);
5826 ext_offset += new_extents[i].offset;
5827 btrfs_set_file_extent_offset(leaf, fi,
5828 ext_offset);
5829 btrfs_mark_buffer_dirty(leaf);
5830
5831 btrfs_drop_extent_cache(inode, key.offset,
5832 key.offset + extent_len - 1, 0);
5833
5834 ret = btrfs_inc_extent_ref(trans, root,
5835 new_extents[i].disk_bytenr,
5836 new_extents[i].disk_num_bytes,
5837 leaf->start,
5838 root->root_key.objectid,
3bb1a1bc 5839 trans->transid, key.objectid);
1a40e23b
ZY		 5840 BUG_ON(ret);
5841 btrfs_release_path(root, path);
5842
a76a3cd4 5843 inode_add_bytes(inode, extent_len);
1a40e23b
ZY		 5844
5845 ext_offset = 0;
5846 num_bytes -= extent_len;
5847 key.offset += extent_len;
5848
5849 if (num_bytes == 0)
5850 break;
5851 }
5852 BUG_ON(i >= nr_extents);
d899e052 5853#endif
1a40e23b
ZY		 5854 }
5855
5856 if (extent_locked) {
1a40e23b
ZY		 5857 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
5858 lock_end, GFP_NOFS);
5859 extent_locked = 0;
5860 }
5861skip:
5862 if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS &&
86288a19 5863 key.offset >= search_end)
1a40e23b
ZY		 5864 break;
5865
5866 cond_resched();
5867 }
5868 ret = 0;
5869out:
5870 btrfs_release_path(root, path);
5871 if (inode) {
5872 mutex_unlock(&inode->i_mutex);
5873 if (extent_locked) {
1a40e23b
ZY		 5874 unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
5875 lock_end, GFP_NOFS);
5876 }
5877 iput(inode);
5878 }
5879 return ret;
5880}
5881
1a40e23b
ZY		 5882int btrfs_reloc_tree_cache_ref(struct btrfs_trans_handle *trans,
5883 struct btrfs_root *root,
5884 struct extent_buffer *buf, u64 orig_start)
5885{
5886 int level;
5887 int ret;
5888
5889 BUG_ON(btrfs_header_generation(buf) != trans->transid);
5890 BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
5891
5892 level = btrfs_header_level(buf);
5893 if (level == 0) {
5894 struct btrfs_leaf_ref *ref;
5895 struct btrfs_leaf_ref *orig_ref;
5896
5897 orig_ref = btrfs_lookup_leaf_ref(root, orig_start);
5898 if (!orig_ref)
5899 return -ENOENT;
5900
5901 ref = btrfs_alloc_leaf_ref(root, orig_ref->nritems);
5902 if (!ref) {
5903 btrfs_free_leaf_ref(root, orig_ref);
5904 return -ENOMEM;
5905 }
5906
5907 ref->nritems = orig_ref->nritems;
5908 memcpy(ref->extents, orig_ref->extents,
5909 sizeof(ref->extents[0]) * ref->nritems);
5910
5911 btrfs_free_leaf_ref(root, orig_ref);
5912
5913 ref->root_gen = trans->transid;
5914 ref->bytenr = buf->start;
5915 ref->owner = btrfs_header_owner(buf);
5916 ref->generation = btrfs_header_generation(buf);
bd56b302 5917
1a40e23b
ZY		 5918 ret = btrfs_add_leaf_ref(root, ref, 0);
5919 WARN_ON(ret);
5920 btrfs_free_leaf_ref(root, ref);
5921 }
5922 return 0;
5923}
5924
d397712b 5925static noinline int invalidate_extent_cache(struct btrfs_root *root,
1a40e23b
ZY		 5926 struct extent_buffer *leaf,
5927 struct btrfs_block_group_cache *group,
5928 struct btrfs_root *target_root)
5929{
5930 struct btrfs_key key;
5931 struct inode *inode = NULL;
5932 struct btrfs_file_extent_item *fi;
5933 u64 num_bytes;
5934 u64 skip_objectid = 0;
5935 u32 nritems;
5936 u32 i;
5937
5938 nritems = btrfs_header_nritems(leaf);
5939 for (i = 0; i < nritems; i++) {
5940 btrfs_item_key_to_cpu(leaf, &key, i);
5941 if (key.objectid == skip_objectid ||
5942 key.type != BTRFS_EXTENT_DATA_KEY)
5943 continue;
5944 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
5945 if (btrfs_file_extent_type(leaf, fi) ==
5946 BTRFS_FILE_EXTENT_INLINE)
5947 continue;
5948 if (btrfs_file_extent_disk_bytenr(leaf, fi) == 0)
5949 continue;
5950 if (!inode || inode->i_ino != key.objectid) {
5951 iput(inode);
5952 inode = btrfs_ilookup(target_root->fs_info->sb,
5953 key.objectid, target_root, 1);
5954 }
5955 if (!inode) {
5956 skip_objectid = key.objectid;
5957 continue;
5958 }
5959 num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
5960
5961 lock_extent(&BTRFS_I(inode)->io_tree, key.offset,
5962 key.offset + num_bytes - 1, GFP_NOFS);
1a40e23b
ZY		 5963 btrfs_drop_extent_cache(inode, key.offset,
5964 key.offset + num_bytes - 1, 1);
1a40e23b
ZY		 5965 unlock_extent(&BTRFS_I(inode)->io_tree, key.offset,
5966 key.offset + num_bytes - 1, GFP_NOFS);
5967 cond_resched();
5968 }
5969 iput(inode);
5970 return 0;
5971}
5972
d397712b 5973static noinline int replace_extents_in_leaf(struct btrfs_trans_handle *trans,
1a40e23b
ZY		 5974 struct btrfs_root *root,
5975 struct extent_buffer *leaf,
5976 struct btrfs_block_group_cache *group,
5977 struct inode *reloc_inode)
5978{
5979 struct btrfs_key key;
5980 struct btrfs_key extent_key;
5981 struct btrfs_file_extent_item *fi;
5982 struct btrfs_leaf_ref *ref;
5983 struct disk_extent *new_extent;
5984 u64 bytenr;
5985 u64 num_bytes;
5986 u32 nritems;
5987 u32 i;
5988 int ext_index;
5989 int nr_extent;
5990 int ret;
5991
5992 new_extent = kmalloc(sizeof(*new_extent), GFP_NOFS);
5993 BUG_ON(!new_extent);
5994
5995 ref = btrfs_lookup_leaf_ref(root, leaf->start);
5996 BUG_ON(!ref);
5997
5998 ext_index = -1;
5999 nritems = btrfs_header_nritems(leaf);
6000 for (i = 0; i < nritems; i++) {
6001 btrfs_item_key_to_cpu(leaf, &key, i);
6002 if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
6003 continue;
6004 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
6005 if (btrfs_file_extent_type(leaf, fi) ==
6006 BTRFS_FILE_EXTENT_INLINE)
6007 continue;
6008 bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
6009 num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
6010 if (bytenr == 0)
6011 continue;
6012
6013 ext_index++;
6014 if (bytenr >= group->key.objectid + group->key.offset ||
6015 bytenr + num_bytes <= group->key.objectid)
6016 continue;
6017
6018 extent_key.objectid = bytenr;
6019 extent_key.offset = num_bytes;
6020 extent_key.type = BTRFS_EXTENT_ITEM_KEY;
6021 nr_extent = 1;
6022 ret = get_new_locations(reloc_inode, &extent_key,
6023 group->key.objectid, 1,
6024 &new_extent, &nr_extent);
6025 if (ret > 0)
6026 continue;
6027 BUG_ON(ret < 0);
6028
6029 BUG_ON(ref->extents[ext_index].bytenr != bytenr);
6030 BUG_ON(ref->extents[ext_index].num_bytes != num_bytes);
6031 ref->extents[ext_index].bytenr = new_extent->disk_bytenr;
6032 ref->extents[ext_index].num_bytes = new_extent->disk_num_bytes;
6033
1a40e23b
ZY		 6034 btrfs_set_file_extent_disk_bytenr(leaf, fi,
6035 new_extent->disk_bytenr);
6036 btrfs_set_file_extent_disk_num_bytes(leaf, fi,
6037 new_extent->disk_num_bytes);
1a40e23b
ZY		 6038 btrfs_mark_buffer_dirty(leaf);
6039
6040 ret = btrfs_inc_extent_ref(trans, root,
6041 new_extent->disk_bytenr,
6042 new_extent->disk_num_bytes,
6043 leaf->start,
6044 root->root_key.objectid,
3bb1a1bc 6045 trans->transid, key.objectid);
1a40e23b 6046 BUG_ON(ret);
56bec294 6047
1a40e23b
ZY		 6048 ret = btrfs_free_extent(trans, root,
6049 bytenr, num_bytes, leaf->start,
6050 btrfs_header_owner(leaf),
6051 btrfs_header_generation(leaf),
3bb1a1bc 6052 key.objectid, 0);
1a40e23b
ZY		 6053 BUG_ON(ret);
6054 cond_resched();
6055 }
6056 kfree(new_extent);
6057 BUG_ON(ext_index + 1 != ref->nritems);
6058 btrfs_free_leaf_ref(root, ref);
6059 return 0;
6060}
6061
f82d02d9
YZ		 6062int btrfs_free_reloc_root(struct btrfs_trans_handle *trans,
6063 struct btrfs_root *root)
1a40e23b
ZY		 6064{
6065 struct btrfs_root *reloc_root;
f82d02d9 6066 int ret;
1a40e23b
ZY		 6067
6068 if (root->reloc_root) {
6069 reloc_root = root->reloc_root;
6070 root->reloc_root = NULL;
6071 list_add(&reloc_root->dead_list,
6072 &root->fs_info->dead_reloc_roots);
f82d02d9
YZ		 6073
6074 btrfs_set_root_bytenr(&reloc_root->root_item,
6075 reloc_root->node->start);
6076 btrfs_set_root_level(&root->root_item,
6077 btrfs_header_level(reloc_root->node));
6078 memset(&reloc_root->root_item.drop_progress, 0,
6079 sizeof(struct btrfs_disk_key));
6080 reloc_root->root_item.drop_level = 0;
6081
6082 ret = btrfs_update_root(trans, root->fs_info->tree_root,
6083 &reloc_root->root_key,
6084 &reloc_root->root_item);
6085 BUG_ON(ret);
1a40e23b
ZY		 6086 }
6087 return 0;
6088}
6089
6090int btrfs_drop_dead_reloc_roots(struct btrfs_root *root)
6091{
6092 struct btrfs_trans_handle *trans;
6093 struct btrfs_root *reloc_root;
6094 struct btrfs_root *prev_root = NULL;
6095 struct list_head dead_roots;
6096 int ret;
6097 unsigned long nr;
6098
6099 INIT_LIST_HEAD(&dead_roots);
6100 list_splice_init(&root->fs_info->dead_reloc_roots, &dead_roots);
6101
6102 while (!list_empty(&dead_roots)) {
6103 reloc_root = list_entry(dead_roots.prev,
6104 struct btrfs_root, dead_list);
6105 list_del_init(&reloc_root->dead_list);
6106
6107 BUG_ON(reloc_root->commit_root != NULL);
6108 while (1) {
6109 trans = btrfs_join_transaction(root, 1);
6110 BUG_ON(!trans);
6111
6112 mutex_lock(&root->fs_info->drop_mutex);
6113 ret = btrfs_drop_snapshot(trans, reloc_root);
6114 if (ret != -EAGAIN)
6115 break;
6116 mutex_unlock(&root->fs_info->drop_mutex);
6117
6118 nr = trans->blocks_used;
6119 ret = btrfs_end_transaction(trans, root);
6120 BUG_ON(ret);
6121 btrfs_btree_balance_dirty(root, nr);
6122 }
6123
6124 free_extent_buffer(reloc_root->node);
6125
6126 ret = btrfs_del_root(trans, root->fs_info->tree_root,
6127 &reloc_root->root_key);
6128 BUG_ON(ret);
6129 mutex_unlock(&root->fs_info->drop_mutex);
6130
6131 nr = trans->blocks_used;
6132 ret = btrfs_end_transaction(trans, root);
6133 BUG_ON(ret);
6134 btrfs_btree_balance_dirty(root, nr);
6135
6136 kfree(prev_root);
6137 prev_root = reloc_root;
6138 }
6139 if (prev_root) {
6140 btrfs_remove_leaf_refs(prev_root, (u64)-1, 0);
6141 kfree(prev_root);
6142 }
6143 return 0;
6144}
6145
6146int btrfs_add_dead_reloc_root(struct btrfs_root *root)
6147{
6148 list_add(&root->dead_list, &root->fs_info->dead_reloc_roots);
6149 return 0;
6150}
6151
6152int btrfs_cleanup_reloc_trees(struct btrfs_root *root)
6153{
6154 struct btrfs_root *reloc_root;
6155 struct btrfs_trans_handle *trans;
6156 struct btrfs_key location;
6157 int found;
6158 int ret;
6159
6160 mutex_lock(&root->fs_info->tree_reloc_mutex);
6161 ret = btrfs_find_dead_roots(root, BTRFS_TREE_RELOC_OBJECTID, NULL);
6162 BUG_ON(ret);
6163 found = !list_empty(&root->fs_info->dead_reloc_roots);
6164 mutex_unlock(&root->fs_info->tree_reloc_mutex);
6165
6166 if (found) {
6167 trans = btrfs_start_transaction(root, 1);
6168 BUG_ON(!trans);
6169 ret = btrfs_commit_transaction(trans, root);
6170 BUG_ON(ret);
6171 }
6172
6173 location.objectid = BTRFS_DATA_RELOC_TREE_OBJECTID;
6174 location.offset = (u64)-1;
6175 location.type = BTRFS_ROOT_ITEM_KEY;
6176
6177 reloc_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
6178 BUG_ON(!reloc_root);
6179 btrfs_orphan_cleanup(reloc_root);
6180 return 0;
6181}
6182
d397712b 6183static noinline int init_reloc_tree(struct btrfs_trans_handle *trans,
1a40e23b
ZY		 6184 struct btrfs_root *root)
6185{
6186 struct btrfs_root *reloc_root;
6187 struct extent_buffer *eb;
6188 struct btrfs_root_item *root_item;
6189 struct btrfs_key root_key;
6190 int ret;
6191
6192 BUG_ON(!root->ref_cows);
6193 if (root->reloc_root)
6194 return 0;
6195
6196 root_item = kmalloc(sizeof(*root_item), GFP_NOFS);
6197 BUG_ON(!root_item);
6198
6199 ret = btrfs_copy_root(trans, root, root->commit_root,
6200 &eb, BTRFS_TREE_RELOC_OBJECTID);
6201 BUG_ON(ret);
6202
6203 root_key.objectid = BTRFS_TREE_RELOC_OBJECTID;
6204 root_key.offset = root->root_key.objectid;
6205 root_key.type = BTRFS_ROOT_ITEM_KEY;
6206
6207 memcpy(root_item, &root->root_item, sizeof(root_item));
6208 btrfs_set_root_refs(root_item, 0);
6209 btrfs_set_root_bytenr(root_item, eb->start);
6210 btrfs_set_root_level(root_item, btrfs_header_level(eb));
84234f3a 6211 btrfs_set_root_generation(root_item, trans->transid);
1a40e23b
ZY		 6212
6213 btrfs_tree_unlock(eb);
6214 free_extent_buffer(eb);
6215
6216 ret = btrfs_insert_root(trans, root->fs_info->tree_root,
6217 &root_key, root_item);
6218 BUG_ON(ret);
6219 kfree(root_item);
6220
6221 reloc_root = btrfs_read_fs_root_no_radix(root->fs_info->tree_root,
6222 &root_key);
6223 BUG_ON(!reloc_root);
6224 reloc_root->last_trans = trans->transid;
6225 reloc_root->commit_root = NULL;
6226 reloc_root->ref_tree = &root->fs_info->reloc_ref_tree;
6227
6228 root->reloc_root = reloc_root;
6229 return 0;
6230}
6231
6232/*
6233 * Core function of space balance.
6234 *
6235 * The idea is using reloc trees to relocate tree blocks in reference
f82d02d9
YZ		 6236 * counted roots. There is one reloc tree for each subvol, and all
6237 * reloc trees share same root key objectid. Reloc trees are snapshots
6238 * of the latest committed roots of subvols (root->commit_root).
6239 *
6240 * To relocate a tree block referenced by a subvol, there are two steps.
6241 * COW the block through subvol's reloc tree, then update block pointer
6242 * in the subvol to point to the new block. Since all reloc trees share
6243 * same root key objectid, doing special handing for tree blocks owned
6244 * by them is easy. Once a tree block has been COWed in one reloc tree,
6245 * we can use the resulting new block directly when the same block is
6246 * required to COW again through other reloc trees. By this way, relocated
6247 * tree blocks are shared between reloc trees, so they are also shared
6248 * between subvols.
1a40e23b 6249 */
d397712b 6250static noinline int relocate_one_path(struct btrfs_trans_handle *trans,
1a40e23b
ZY		 6251 struct btrfs_root *root,
6252 struct btrfs_path *path,
6253 struct btrfs_key *first_key,
6254 struct btrfs_ref_path *ref_path,
6255 struct btrfs_block_group_cache *group,
6256 struct inode *reloc_inode)
6257{
6258 struct btrfs_root *reloc_root;
6259 struct extent_buffer *eb = NULL;
6260 struct btrfs_key *keys;
6261 u64 *nodes;
6262 int level;
f82d02d9 6263 int shared_level;
1a40e23b 6264 int lowest_level = 0;
1a40e23b
ZY		 6265 int ret;
6266
6267 if (ref_path->owner_objectid < BTRFS_FIRST_FREE_OBJECTID)
6268 lowest_level = ref_path->owner_objectid;
6269
f82d02d9 6270 if (!root->ref_cows) {
1a40e23b
ZY		 6271 path->lowest_level = lowest_level;
6272 ret = btrfs_search_slot(trans, root, first_key, path, 0, 1);
6273 BUG_ON(ret < 0);
6274 path->lowest_level = 0;
6275 btrfs_release_path(root, path);
6276 return 0;
6277 }
6278
1a40e23b
ZY		 6279 mutex_lock(&root->fs_info->tree_reloc_mutex);
6280 ret = init_reloc_tree(trans, root);
6281 BUG_ON(ret);
6282 reloc_root = root->reloc_root;
6283
f82d02d9
YZ		 6284 shared_level = ref_path->shared_level;
6285 ref_path->shared_level = BTRFS_MAX_LEVEL - 1;
1a40e23b 6286
f82d02d9
YZ		 6287 keys = ref_path->node_keys;
6288 nodes = ref_path->new_nodes;
6289 memset(&keys[shared_level + 1], 0,
6290 sizeof(*keys) * (BTRFS_MAX_LEVEL - shared_level - 1));
6291 memset(&nodes[shared_level + 1], 0,
6292 sizeof(*nodes) * (BTRFS_MAX_LEVEL - shared_level - 1));
1a40e23b 6293
f82d02d9
YZ		 6294 if (nodes[lowest_level] == 0) {
6295 path->lowest_level = lowest_level;
6296 ret = btrfs_search_slot(trans, reloc_root, first_key, path,
6297 0, 1);
6298 BUG_ON(ret);
6299 for (level = lowest_level; level < BTRFS_MAX_LEVEL; level++) {
6300 eb = path->nodes[level];
6301 if (!eb || eb == reloc_root->node)
6302 break;
6303 nodes[level] = eb->start;
6304 if (level == 0)
6305 btrfs_item_key_to_cpu(eb, &keys[level], 0);
6306 else
6307 btrfs_node_key_to_cpu(eb, &keys[level], 0);
6308 }
2b82032c
YZ		 6309 if (nodes[0] &&
6310 ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
f82d02d9
YZ		 6311 eb = path->nodes[0];
6312 ret = replace_extents_in_leaf(trans, reloc_root, eb,
6313 group, reloc_inode);
6314 BUG_ON(ret);
6315 }
6316 btrfs_release_path(reloc_root, path);
6317 } else {
1a40e23b 6318 ret = btrfs_merge_path(trans, reloc_root, keys, nodes,
f82d02d9 6319 lowest_level);
1a40e23b
ZY		 6320 BUG_ON(ret);
6321 }
6322
1a40e23b
ZY		 6323 /*
6324 * replace tree blocks in the fs tree with tree blocks in
6325 * the reloc tree.
6326 */
6327 ret = btrfs_merge_path(trans, root, keys, nodes, lowest_level);
6328 BUG_ON(ret < 0);
6329
6330 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
f82d02d9
YZ		 6331 ret = btrfs_search_slot(trans, reloc_root, first_key, path,
6332 0, 0);
6333 BUG_ON(ret);
6334 extent_buffer_get(path->nodes[0]);
6335 eb = path->nodes[0];
6336 btrfs_release_path(reloc_root, path);
1a40e23b
ZY		 6337 ret = invalidate_extent_cache(reloc_root, eb, group, root);
6338 BUG_ON(ret);
6339 free_extent_buffer(eb);
6340 }
1a40e23b 6341
f82d02d9 6342 mutex_unlock(&root->fs_info->tree_reloc_mutex);
1a40e23b 6343 path->lowest_level = 0;
1a40e23b
ZY		 6344 return 0;
6345}
6346
d397712b 6347static noinline int relocate_tree_block(struct btrfs_trans_handle *trans,
1a40e23b
ZY		 6348 struct btrfs_root *root,
6349 struct btrfs_path *path,
6350 struct btrfs_key *first_key,
6351 struct btrfs_ref_path *ref_path)
6352{
6353 int ret;
1a40e23b
ZY		 6354
6355 ret = relocate_one_path(trans, root, path, first_key,
6356 ref_path, NULL, NULL);
6357 BUG_ON(ret);
6358
1a40e23b
ZY		 6359 return 0;
6360}
6361
d397712b 6362static noinline int del_extent_zero(struct btrfs_trans_handle *trans,
1a40e23b
ZY		 6363 struct btrfs_root *extent_root,
6364 struct btrfs_path *path,
6365 struct btrfs_key *extent_key)
6366{
6367 int ret;
6368
1a40e23b
ZY		 6369 ret = btrfs_search_slot(trans, extent_root, extent_key, path, -1, 1);
6370 if (ret)
6371 goto out;
6372 ret = btrfs_del_item(trans, extent_root, path);
6373out:
6374 btrfs_release_path(extent_root, path);
1a40e23b
ZY		 6375 return ret;
6376}
6377
d397712b 6378static noinline struct btrfs_root *read_ref_root(struct btrfs_fs_info *fs_info,
1a40e23b
ZY		 6379 struct btrfs_ref_path *ref_path)
6380{
6381 struct btrfs_key root_key;
6382
6383 root_key.objectid = ref_path->root_objectid;
6384 root_key.type = BTRFS_ROOT_ITEM_KEY;
6385 if (is_cowonly_root(ref_path->root_objectid))
6386 root_key.offset = 0;
6387 else
6388 root_key.offset = (u64)-1;
6389
6390 return btrfs_read_fs_root_no_name(fs_info, &root_key);
6391}
6392
d397712b 6393static noinline int relocate_one_extent(struct btrfs_root *extent_root,
1a40e23b
ZY		 6394 struct btrfs_path *path,
6395 struct btrfs_key *extent_key,
6396 struct btrfs_block_group_cache *group,
6397 struct inode *reloc_inode, int pass)
6398{
6399 struct btrfs_trans_handle *trans;
6400 struct btrfs_root *found_root;
6401 struct btrfs_ref_path *ref_path = NULL;
6402 struct disk_extent *new_extents = NULL;
6403 int nr_extents = 0;
6404 int loops;
6405 int ret;
6406 int level;
6407 struct btrfs_key first_key;
6408 u64 prev_block = 0;
6409
1a40e23b
ZY		 6410
6411 trans = btrfs_start_transaction(extent_root, 1);
6412 BUG_ON(!trans);
6413
6414 if (extent_key->objectid == 0) {
6415 ret = del_extent_zero(trans, extent_root, path, extent_key);
6416 goto out;
6417 }
6418
6419 ref_path = kmalloc(sizeof(*ref_path), GFP_NOFS);
6420 if (!ref_path) {
d397712b
CM		 6421 ret = -ENOMEM;
6422 goto out;
1a40e23b
ZY		 6423 }
6424
6425 for (loops = 0; ; loops++) {
6426 if (loops == 0) {
6427 ret = btrfs_first_ref_path(trans, extent_root, ref_path,
6428 extent_key->objectid);
6429 } else {
6430 ret = btrfs_next_ref_path(trans, extent_root, ref_path);
6431 }
6432 if (ret < 0)
6433 goto out;
6434 if (ret > 0)
6435 break;
6436
6437 if (ref_path->root_objectid == BTRFS_TREE_LOG_OBJECTID ||
6438 ref_path->root_objectid == BTRFS_TREE_RELOC_OBJECTID)
6439 continue;
6440
6441 found_root = read_ref_root(extent_root->fs_info, ref_path);
6442 BUG_ON(!found_root);
6443 /*
6444 * for reference counted tree, only process reference paths
6445 * rooted at the latest committed root.
6446 */
6447 if (found_root->ref_cows &&
6448 ref_path->root_generation != found_root->root_key.offset)
6449 continue;
6450
6451 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
6452 if (pass == 0) {
6453 /*
6454 * copy data extents to new locations
6455 */
6456 u64 group_start = group->key.objectid;
6457 ret = relocate_data_extent(reloc_inode,
6458 extent_key,
6459 group_start);
6460 if (ret < 0)
6461 goto out;
6462 break;
6463 }
6464 level = 0;
6465 } else {
6466 level = ref_path->owner_objectid;
6467 }
6468
6469 if (prev_block != ref_path->nodes[level]) {
6470 struct extent_buffer *eb;
6471 u64 block_start = ref_path->nodes[level];
6472 u64 block_size = btrfs_level_size(found_root, level);
6473
6474 eb = read_tree_block(found_root, block_start,
6475 block_size, 0);
6476 btrfs_tree_lock(eb);
6477 BUG_ON(level != btrfs_header_level(eb));
6478
6479 if (level == 0)
6480 btrfs_item_key_to_cpu(eb, &first_key, 0);
6481 else
6482 btrfs_node_key_to_cpu(eb, &first_key, 0);
6483
6484 btrfs_tree_unlock(eb);
6485 free_extent_buffer(eb);
6486 prev_block = block_start;
6487 }
6488
24562425 6489 mutex_lock(&extent_root->fs_info->trans_mutex);
e4404d6e 6490 btrfs_record_root_in_trans(found_root);
24562425 6491 mutex_unlock(&extent_root->fs_info->trans_mutex);
e4404d6e
YZ		 6492 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
6493 /*
6494 * try to update data extent references while
6495 * keeping metadata shared between snapshots.
6496 */
6497 if (pass == 1) {
6498 ret = relocate_one_path(trans, found_root,
6499 path, &first_key, ref_path,
6500 group, reloc_inode);
6501 if (ret < 0)
6502 goto out;
6503 continue;
6504 }
1a40e23b
ZY		 6505 /*
6506 * use fallback method to process the remaining
6507 * references.
6508 */
6509 if (!new_extents) {
6510 u64 group_start = group->key.objectid;
d899e052
YZ		 6511 new_extents = kmalloc(sizeof(*new_extents),
6512 GFP_NOFS);
6513 nr_extents = 1;
1a40e23b
ZY		 6514 ret = get_new_locations(reloc_inode,
6515 extent_key,
d899e052 6516 group_start, 1,
1a40e23b
ZY		 6517 &new_extents,
6518 &nr_extents);
d899e052 6519 if (ret)
1a40e23b
ZY		 6520 goto out;
6521 }
1a40e23b
ZY		 6522 ret = replace_one_extent(trans, found_root,
6523 path, extent_key,
6524 &first_key, ref_path,
6525 new_extents, nr_extents);
e4404d6e 6526 } else {
1a40e23b
ZY		 6527 ret = relocate_tree_block(trans, found_root, path,
6528 &first_key, ref_path);
1a40e23b
ZY		 6529 }
6530 if (ret < 0)
6531 goto out;
6532 }
6533 ret = 0;
6534out:
6535 btrfs_end_transaction(trans, extent_root);
6536 kfree(new_extents);
6537 kfree(ref_path);
1a40e23b
ZY		 6538 return ret;
6539}
5d4f98a2 6540#endif
1a40e23b 6541
ec44a35c
CM		 6542static u64 update_block_group_flags(struct btrfs_root *root, u64 flags)
6543{
6544 u64 num_devices;
6545 u64 stripped = BTRFS_BLOCK_GROUP_RAID0 |
6546 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
6547
2b82032c 6548 num_devices = root->fs_info->fs_devices->rw_devices;
ec44a35c
CM		 6549 if (num_devices == 1) {
6550 stripped |= BTRFS_BLOCK_GROUP_DUP;
6551 stripped = flags & ~stripped;
6552
6553 /* turn raid0 into single device chunks */
6554 if (flags & BTRFS_BLOCK_GROUP_RAID0)
6555 return stripped;
6556
6557 /* turn mirroring into duplication */
6558 if (flags & (BTRFS_BLOCK_GROUP_RAID1 |
6559 BTRFS_BLOCK_GROUP_RAID10))
6560 return stripped | BTRFS_BLOCK_GROUP_DUP;
6561 return flags;
6562 } else {
6563 /* they already had raid on here, just return */
ec44a35c
CM		 6564 if (flags & stripped)
6565 return flags;
6566
6567 stripped |= BTRFS_BLOCK_GROUP_DUP;
6568 stripped = flags & ~stripped;
6569
6570 /* switch duplicated blocks with raid1 */
6571 if (flags & BTRFS_BLOCK_GROUP_DUP)
6572 return stripped | BTRFS_BLOCK_GROUP_RAID1;
6573
6574 /* turn single device chunks into raid0 */
6575 return stripped | BTRFS_BLOCK_GROUP_RAID0;
6576 }
6577 return flags;
6578}
6579
b2950863 6580static int __alloc_chunk_for_shrink(struct btrfs_root *root,
0ef3e66b
CM		 6581 struct btrfs_block_group_cache *shrink_block_group,
6582 int force)
6583{
6584 struct btrfs_trans_handle *trans;
6585 u64 new_alloc_flags;
6586 u64 calc;
6587
c286ac48 6588 spin_lock(&shrink_block_group->lock);
5d4f98a2
YZ		 6589 if (btrfs_block_group_used(&shrink_block_group->item) +
6590 shrink_block_group->reserved > 0) {
c286ac48 6591 spin_unlock(&shrink_block_group->lock);
c286ac48 6592
0ef3e66b 6593 trans = btrfs_start_transaction(root, 1);
c286ac48 6594 spin_lock(&shrink_block_group->lock);
7d9eb12c 6595
0ef3e66b
CM		 6596 new_alloc_flags = update_block_group_flags(root,
6597 shrink_block_group->flags);
6598 if (new_alloc_flags != shrink_block_group->flags) {
6599 calc =
6600 btrfs_block_group_used(&shrink_block_group->item);
6601 } else {
6602 calc = shrink_block_group->key.offset;
6603 }
c286ac48
CM		 6604 spin_unlock(&shrink_block_group->lock);
6605
0ef3e66b
CM		 6606 do_chunk_alloc(trans, root->fs_info->extent_root,
6607 calc + 2 * 1024 * 1024, new_alloc_flags, force);
7d9eb12c 6608
0ef3e66b 6609 btrfs_end_transaction(trans, root);
c286ac48
CM		 6610 } else
6611 spin_unlock(&shrink_block_group->lock);
0ef3e66b
CM		 6612 return 0;
6613}
6614
5d4f98a2
YZ		 6615
6616int btrfs_prepare_block_group_relocation(struct btrfs_root *root,
6617 struct btrfs_block_group_cache *group)
6618
6619{
6620 __alloc_chunk_for_shrink(root, group, 1);
6621 set_block_group_readonly(group);
6622 return 0;
6623}
6624
6625#if 0
1a40e23b
ZY		 6626static int __insert_orphan_inode(struct btrfs_trans_handle *trans,
6627 struct btrfs_root *root,
6628 u64 objectid, u64 size)
6629{
6630 struct btrfs_path *path;
6631 struct btrfs_inode_item *item;
6632 struct extent_buffer *leaf;
6633 int ret;
6634
6635 path = btrfs_alloc_path();
6636 if (!path)
6637 return -ENOMEM;
6638
b9473439 6639 path->leave_spinning = 1;
1a40e23b
ZY		 6640 ret = btrfs_insert_empty_inode(trans, root, path, objectid);
6641 if (ret)
6642 goto out;
6643
6644 leaf = path->nodes[0];
6645 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item);
6646 memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item));
6647 btrfs_set_inode_generation(leaf, item, 1);
6648 btrfs_set_inode_size(leaf, item, size);
6649 btrfs_set_inode_mode(leaf, item, S_IFREG | 0600);
0403e47e 6650 btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NOCOMPRESS);
1a40e23b
ZY		 6651 btrfs_mark_buffer_dirty(leaf);
6652 btrfs_release_path(root, path);
6653out:
6654 btrfs_free_path(path);
6655 return ret;
6656}
6657
d397712b 6658static noinline struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info,
1a40e23b
ZY		 6659 struct btrfs_block_group_cache *group)
6660{
6661 struct inode *inode = NULL;
6662 struct btrfs_trans_handle *trans;
6663 struct btrfs_root *root;
6664 struct btrfs_key root_key;
6665 u64 objectid = BTRFS_FIRST_FREE_OBJECTID;
6666 int err = 0;
6667
6668 root_key.objectid = BTRFS_DATA_RELOC_TREE_OBJECTID;
6669 root_key.type = BTRFS_ROOT_ITEM_KEY;
6670 root_key.offset = (u64)-1;
6671 root = btrfs_read_fs_root_no_name(fs_info, &root_key);
6672 if (IS_ERR(root))
6673 return ERR_CAST(root);
6674
6675 trans = btrfs_start_transaction(root, 1);
6676 BUG_ON(!trans);
6677
6678 err = btrfs_find_free_objectid(trans, root, objectid, &objectid);
6679 if (err)
6680 goto out;
6681
6682 err = __insert_orphan_inode(trans, root, objectid, group->key.offset);
6683 BUG_ON(err);
6684
6685 err = btrfs_insert_file_extent(trans, root, objectid, 0, 0, 0,
c8b97818
CM		 6686 group->key.offset, 0, group->key.offset,
6687 0, 0, 0);
1a40e23b
ZY		 6688 BUG_ON(err);
6689
6690 inode = btrfs_iget_locked(root->fs_info->sb, objectid, root);
6691 if (inode->i_state & I_NEW) {
6692 BTRFS_I(inode)->root = root;
6693 BTRFS_I(inode)->location.objectid = objectid;
6694 BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY;
6695 BTRFS_I(inode)->location.offset = 0;
6696 btrfs_read_locked_inode(inode);
6697 unlock_new_inode(inode);
6698 BUG_ON(is_bad_inode(inode));
6699 } else {
6700 BUG_ON(1);
6701 }
17d217fe 6702 BTRFS_I(inode)->index_cnt = group->key.objectid;
1a40e23b
ZY		 6703
6704 err = btrfs_orphan_add(trans, inode);
6705out:
6706 btrfs_end_transaction(trans, root);
6707 if (err) {
6708 if (inode)
6709 iput(inode);
6710 inode = ERR_PTR(err);
6711 }
6712 return inode;
6713}
6714
17d217fe
YZ		 6715int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len)
6716{
6717
6718 struct btrfs_ordered_sum *sums;
6719 struct btrfs_sector_sum *sector_sum;
6720 struct btrfs_ordered_extent *ordered;
6721 struct btrfs_root *root = BTRFS_I(inode)->root;
6722 struct list_head list;
6723 size_t offset;
6724 int ret;
6725 u64 disk_bytenr;
6726
6727 INIT_LIST_HEAD(&list);
6728
6729 ordered = btrfs_lookup_ordered_extent(inode, file_pos);
6730 BUG_ON(ordered->file_offset != file_pos || ordered->len != len);
6731
6732 disk_bytenr = file_pos + BTRFS_I(inode)->index_cnt;
07d400a6 6733 ret = btrfs_lookup_csums_range(root->fs_info->csum_root, disk_bytenr,
17d217fe
YZ		 6734 disk_bytenr + len - 1, &list);
6735
6736 while (!list_empty(&list)) {
6737 sums = list_entry(list.next, struct btrfs_ordered_sum, list);
6738 list_del_init(&sums->list);
6739
6740 sector_sum = sums->sums;
6741 sums->bytenr = ordered->start;
6742
6743 offset = 0;
6744 while (offset < sums->len) {
6745 sector_sum->bytenr += ordered->start - disk_bytenr;
6746 sector_sum++;
6747 offset += root->sectorsize;
6748 }
6749
6750 btrfs_add_ordered_sum(inode, ordered, sums);
6751 }
6752 btrfs_put_ordered_extent(ordered);
6753 return 0;
6754}
6755
1a40e23b 6756int btrfs_relocate_block_group(struct btrfs_root *root, u64 group_start)
edbd8d4e
CM		 6757{
6758 struct btrfs_trans_handle *trans;
edbd8d4e 6759 struct btrfs_path *path;
1a40e23b
ZY		 6760 struct btrfs_fs_info *info = root->fs_info;
6761 struct extent_buffer *leaf;
6762 struct inode *reloc_inode;
6763 struct btrfs_block_group_cache *block_group;
6764 struct btrfs_key key;
d899e052 6765 u64 skipped;
edbd8d4e
CM		 6766 u64 cur_byte;
6767 u64 total_found;
edbd8d4e
CM		 6768 u32 nritems;
6769 int ret;
a061fc8d 6770 int progress;
1a40e23b 6771 int pass = 0;
edbd8d4e 6772
1a40e23b
ZY		 6773 root = root->fs_info->extent_root;
6774
6775 block_group = btrfs_lookup_block_group(info, group_start);
6776 BUG_ON(!block_group);
8f18cf13 6777
d397712b 6778 printk(KERN_INFO "btrfs relocating block group %llu flags %llu\n",
1a40e23b
ZY		 6779 (unsigned long long)block_group->key.objectid,
6780 (unsigned long long)block_group->flags);
8f18cf13 6781
edbd8d4e 6782 path = btrfs_alloc_path();
1a40e23b 6783 BUG_ON(!path);
edbd8d4e 6784
1a40e23b
ZY		 6785 reloc_inode = create_reloc_inode(info, block_group);
6786 BUG_ON(IS_ERR(reloc_inode));
323da79c 6787
1a40e23b 6788 __alloc_chunk_for_shrink(root, block_group, 1);
c146afad 6789 set_block_group_readonly(block_group);
323da79c 6790
1a40e23b
ZY		 6791 btrfs_start_delalloc_inodes(info->tree_root);
6792 btrfs_wait_ordered_extents(info->tree_root, 0);
6793again:
d899e052 6794 skipped = 0;
edbd8d4e 6795 total_found = 0;
a061fc8d 6796 progress = 0;
1a40e23b 6797 key.objectid = block_group->key.objectid;
edbd8d4e
CM		 6798 key.offset = 0;
6799 key.type = 0;
73e48b27 6800 cur_byte = key.objectid;
4313b399 6801
1a40e23b
ZY		 6802 trans = btrfs_start_transaction(info->tree_root, 1);
6803 btrfs_commit_transaction(trans, info->tree_root);
ea8c2819 6804
1a40e23b
ZY		 6805 mutex_lock(&root->fs_info->cleaner_mutex);
6806 btrfs_clean_old_snapshots(info->tree_root);
6807 btrfs_remove_leaf_refs(info->tree_root, (u64)-1, 1);
6808 mutex_unlock(&root->fs_info->cleaner_mutex);
ea8c2819 6809
56bec294
CM		 6810 trans = btrfs_start_transaction(info->tree_root, 1);
6811 btrfs_commit_transaction(trans, info->tree_root);
6812
d397712b 6813 while (1) {
edbd8d4e
CM		 6814 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6815 if (ret < 0)
6816 goto out;
7d9eb12c 6817next:
edbd8d4e 6818 leaf = path->nodes[0];
73e48b27 6819 nritems = btrfs_header_nritems(leaf);
73e48b27
Y		 6820 if (path->slots[0] >= nritems) {
6821 ret = btrfs_next_leaf(root, path);
6822 if (ret < 0)
6823 goto out;
6824 if (ret == 1) {
6825 ret = 0;
6826 break;
edbd8d4e 6827 }
73e48b27
Y		 6828 leaf = path->nodes[0];
6829 nritems = btrfs_header_nritems(leaf);
edbd8d4e 6830 }
73e48b27 6831
1a40e23b 6832 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
725c8463 6833
1a40e23b
ZY		 6834 if (key.objectid >= block_group->key.objectid +
6835 block_group->key.offset)
8f18cf13
CM		 6836 break;
6837
725c8463 6838 if (progress && need_resched()) {
725c8463 6839 btrfs_release_path(root, path);
1a40e23b 6840 cond_resched();
725c8463 6841 progress = 0;
1a40e23b 6842 continue;
725c8463
CM		 6843 }
6844 progress = 1;
6845
1a40e23b
ZY		 6846 if (btrfs_key_type(&key) != BTRFS_EXTENT_ITEM_KEY ||
6847 key.objectid + key.offset <= cur_byte) {
edbd8d4e 6848 path->slots[0]++;
edbd8d4e
CM		 6849 goto next;
6850 }
73e48b27 6851
edbd8d4e 6852 total_found++;
1a40e23b 6853 cur_byte = key.objectid + key.offset;
edbd8d4e 6854 btrfs_release_path(root, path);
edbd8d4e 6855
1a40e23b
ZY		 6856 __alloc_chunk_for_shrink(root, block_group, 0);
6857 ret = relocate_one_extent(root, path, &key, block_group,
6858 reloc_inode, pass);
6859 BUG_ON(ret < 0);
d899e052
YZ		 6860 if (ret > 0)
6861 skipped++;
edbd8d4e 6862
1a40e23b
ZY		 6863 key.objectid = cur_byte;
6864 key.type = 0;
6865 key.offset = 0;
edbd8d4e
CM		 6866 }
6867
1a40e23b 6868 btrfs_release_path(root, path);
7d9eb12c 6869
1a40e23b
ZY		 6870 if (pass == 0) {
6871 btrfs_wait_ordered_range(reloc_inode, 0, (u64)-1);
6872 invalidate_mapping_pages(reloc_inode->i_mapping, 0, -1);
8e8a1e31 6873 }
73e48b27 6874
1a40e23b 6875 if (total_found > 0) {
d397712b 6876 printk(KERN_INFO "btrfs found %llu extents in pass %d\n",
1a40e23b
ZY		 6877 (unsigned long long)total_found, pass);
6878 pass++;
d899e052
YZ		 6879 if (total_found == skipped && pass > 2) {
6880 iput(reloc_inode);
6881 reloc_inode = create_reloc_inode(info, block_group);
6882 pass = 0;
6883 }
1a40e23b 6884 goto again;
0f9dd46c 6885 }
0ef3e66b 6886
1a40e23b
ZY		 6887 /* delete reloc_inode */
6888 iput(reloc_inode);
6889
6890 /* unpin extents in this range */
6891 trans = btrfs_start_transaction(info->tree_root, 1);
6892 btrfs_commit_transaction(trans, info->tree_root);
0ef3e66b 6893
1a40e23b
ZY		 6894 spin_lock(&block_group->lock);
6895 WARN_ON(block_group->pinned > 0);
6896 WARN_ON(block_group->reserved > 0);
6897 WARN_ON(btrfs_block_group_used(&block_group->item) > 0);
6898 spin_unlock(&block_group->lock);
fa9c0d79 6899 btrfs_put_block_group(block_group);
1a40e23b 6900 ret = 0;
edbd8d4e 6901out:
1a40e23b 6902 btrfs_free_path(path);
edbd8d4e
CM		 6903 return ret;
6904}
5d4f98a2 6905#endif
edbd8d4e 6906
b2950863
CH		 6907static int find_first_block_group(struct btrfs_root *root,
6908 struct btrfs_path *path, struct btrfs_key *key)
0b86a832 6909{
925baedd 6910 int ret = 0;
0b86a832
CM		 6911 struct btrfs_key found_key;
6912 struct extent_buffer *leaf;
6913 int slot;
edbd8d4e 6914
0b86a832
CM		 6915 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
6916 if (ret < 0)
925baedd
CM		 6917 goto out;
6918
d397712b 6919 while (1) {
0b86a832 6920 slot = path->slots[0];
edbd8d4e 6921 leaf = path->nodes[0];
0b86a832
CM		 6922 if (slot >= btrfs_header_nritems(leaf)) {
6923 ret = btrfs_next_leaf(root, path);
6924 if (ret == 0)
6925 continue;
6926 if (ret < 0)
925baedd 6927 goto out;
0b86a832 6928 break;
edbd8d4e 6929 }
0b86a832 6930 btrfs_item_key_to_cpu(leaf, &found_key, slot);
edbd8d4e 6931
0b86a832 6932 if (found_key.objectid >= key->objectid &&
925baedd
CM		 6933 found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
6934 ret = 0;
6935 goto out;
6936 }
0b86a832 6937 path->slots[0]++;
edbd8d4e 6938 }
0b86a832 6939 ret = -ENOENT;
925baedd 6940out:
0b86a832 6941 return ret;
edbd8d4e
CM		 6942}
6943
1a40e23b
ZY		 6944int btrfs_free_block_groups(struct btrfs_fs_info *info)
6945{
6946 struct btrfs_block_group_cache *block_group;
4184ea7f 6947 struct btrfs_space_info *space_info;
1a40e23b
ZY		 6948 struct rb_node *n;
6949
1a40e23b
ZY		 6950 spin_lock(&info->block_group_cache_lock);
6951 while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
6952 block_group = rb_entry(n, struct btrfs_block_group_cache,
6953 cache_node);
1a40e23b
ZY		 6954 rb_erase(&block_group->cache_node,
6955 &info->block_group_cache_tree);
d899e052
YZ		 6956 spin_unlock(&info->block_group_cache_lock);
6957
6958 btrfs_remove_free_space_cache(block_group);
80eb234a 6959 down_write(&block_group->space_info->groups_sem);
1a40e23b 6960 list_del(&block_group->list);
80eb234a 6961 up_write(&block_group->space_info->groups_sem);
d2fb3437
YZ		 6962
6963 WARN_ON(atomic_read(&block_group->count) != 1);
1a40e23b 6964 kfree(block_group);
d899e052
YZ		 6965
6966 spin_lock(&info->block_group_cache_lock);
1a40e23b
ZY		 6967 }
6968 spin_unlock(&info->block_group_cache_lock);
4184ea7f
CM		 6969
6970 /* now that all the block groups are freed, go through and
6971 * free all the space_info structs. This is only called during
6972 * the final stages of unmount, and so we know nobody is
6973 * using them. We call synchronize_rcu() once before we start,
6974 * just to be on the safe side.
6975 */
6976 synchronize_rcu();
6977
6978 while(!list_empty(&info->space_info)) {
6979 space_info = list_entry(info->space_info.next,
6980 struct btrfs_space_info,
6981 list);
6982
6983 list_del(&space_info->list);
6984 kfree(space_info);
6985 }
1a40e23b
ZY		 6986 return 0;
6987}
6988
9078a3e1
CM		 6989int btrfs_read_block_groups(struct btrfs_root *root)
6990{
6991 struct btrfs_path *path;
6992 int ret;
9078a3e1 6993 struct btrfs_block_group_cache *cache;
be744175 6994 struct btrfs_fs_info *info = root->fs_info;
6324fbf3 6995 struct btrfs_space_info *space_info;
9078a3e1
CM		 6996 struct btrfs_key key;
6997 struct btrfs_key found_key;
5f39d397 6998 struct extent_buffer *leaf;
96b5179d 6999
be744175 7000 root = info->extent_root;
9078a3e1 7001 key.objectid = 0;
0b86a832 7002 key.offset = 0;
9078a3e1 7003 btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
9078a3e1
CM		 7004 path = btrfs_alloc_path();
7005 if (!path)
7006 return -ENOMEM;
7007
d397712b 7008 while (1) {
0b86a832
CM		 7009 ret = find_first_block_group(root, path, &key);
7010 if (ret > 0) {
7011 ret = 0;
7012 goto error;
9078a3e1 7013 }
0b86a832
CM		 7014 if (ret != 0)
7015 goto error;
7016
5f39d397
CM		 7017 leaf = path->nodes[0];
7018 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
8f18cf13 7019 cache = kzalloc(sizeof(*cache), GFP_NOFS);
9078a3e1 7020 if (!cache) {
0b86a832 7021 ret = -ENOMEM;
9078a3e1
CM		 7022 break;
7023 }
3e1ad54f 7024
d2fb3437 7025 atomic_set(&cache->count, 1);
c286ac48 7026 spin_lock_init(&cache->lock);
6226cb0a 7027 spin_lock_init(&cache->tree_lock);
ea6a478e 7028 mutex_init(&cache->cache_mutex);
0f9dd46c 7029 INIT_LIST_HEAD(&cache->list);
fa9c0d79 7030 INIT_LIST_HEAD(&cache->cluster_list);
5f39d397
CM		 7031 read_extent_buffer(leaf, &cache->item,
7032 btrfs_item_ptr_offset(leaf, path->slots[0]),
7033 sizeof(cache->item));
9078a3e1 7034 memcpy(&cache->key, &found_key, sizeof(found_key));
0b86a832 7035
9078a3e1
CM		 7036 key.objectid = found_key.objectid + found_key.offset;
7037 btrfs_release_path(root, path);
0b86a832 7038 cache->flags = btrfs_block_group_flags(&cache->item);
96b5179d 7039
6324fbf3
CM		 7040 ret = update_space_info(info, cache->flags, found_key.offset,
7041 btrfs_block_group_used(&cache->item),
7042 &space_info);
7043 BUG_ON(ret);
7044 cache->space_info = space_info;
80eb234a
JB		 7045 down_write(&space_info->groups_sem);
7046 list_add_tail(&cache->list, &space_info->block_groups);
7047 up_write(&space_info->groups_sem);
0f9dd46c
JB		 7048
7049 ret = btrfs_add_block_group_cache(root->fs_info, cache);
7050 BUG_ON(ret);
75ccf47d
CM		 7051
7052 set_avail_alloc_bits(root->fs_info, cache->flags);
2b82032c
YZ		 7053 if (btrfs_chunk_readonly(root, cache->key.objectid))
7054 set_block_group_readonly(cache);
9078a3e1 7055 }
0b86a832
CM		 7056 ret = 0;
7057error:
9078a3e1 7058 btrfs_free_path(path);
0b86a832 7059 return ret;
9078a3e1 7060}
6324fbf3
CM		 7061
7062int btrfs_make_block_group(struct btrfs_trans_handle *trans,
7063 struct btrfs_root *root, u64 bytes_used,
e17cade2 7064 u64 type, u64 chunk_objectid, u64 chunk_offset,
6324fbf3
CM		 7065 u64 size)
7066{
7067 int ret;
6324fbf3
CM		 7068 struct btrfs_root *extent_root;
7069 struct btrfs_block_group_cache *cache;
6324fbf3
CM		 7070
7071 extent_root = root->fs_info->extent_root;
6324fbf3 7072
12fcfd22 7073 root->fs_info->last_trans_log_full_commit = trans->transid;
e02119d5 7074
8f18cf13 7075 cache = kzalloc(sizeof(*cache), GFP_NOFS);
0f9dd46c
JB		 7076 if (!cache)
7077 return -ENOMEM;
7078
e17cade2 7079 cache->key.objectid = chunk_offset;
6324fbf3 7080 cache->key.offset = size;
d2fb3437
YZ		 7081 cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
7082 atomic_set(&cache->count, 1);
c286ac48 7083 spin_lock_init(&cache->lock);
6226cb0a 7084 spin_lock_init(&cache->tree_lock);
ea6a478e 7085 mutex_init(&cache->cache_mutex);
0f9dd46c 7086 INIT_LIST_HEAD(&cache->list);
fa9c0d79 7087 INIT_LIST_HEAD(&cache->cluster_list);
0ef3e66b 7088
6324fbf3 7089 btrfs_set_block_group_used(&cache->item, bytes_used);
6324fbf3
CM		 7090 btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
7091 cache->flags = type;
7092 btrfs_set_block_group_flags(&cache->item, type);
7093
7094 ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
7095 &cache->space_info);
7096 BUG_ON(ret);
80eb234a
JB		 7097 down_write(&cache->space_info->groups_sem);
7098 list_add_tail(&cache->list, &cache->space_info->block_groups);
7099 up_write(&cache->space_info->groups_sem);
6324fbf3 7100
0f9dd46c
JB		 7101 ret = btrfs_add_block_group_cache(root->fs_info, cache);
7102 BUG_ON(ret);
c286ac48 7103
6324fbf3
CM		 7104 ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
7105 sizeof(cache->item));
7106 BUG_ON(ret);
7107
d18a2c44 7108 set_avail_alloc_bits(extent_root->fs_info, type);
925baedd 7109
6324fbf3
CM		 7110 return 0;
7111}
1a40e23b
ZY		 7112
7113int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
7114 struct btrfs_root *root, u64 group_start)
7115{
7116 struct btrfs_path *path;
7117 struct btrfs_block_group_cache *block_group;
44fb5511 7118 struct btrfs_free_cluster *cluster;
1a40e23b
ZY		 7119 struct btrfs_key key;
7120 int ret;
7121
1a40e23b
ZY		 7122 root = root->fs_info->extent_root;
7123
7124 block_group = btrfs_lookup_block_group(root->fs_info, group_start);
7125 BUG_ON(!block_group);
c146afad 7126 BUG_ON(!block_group->ro);
1a40e23b
ZY		 7127
7128 memcpy(&key, &block_group->key, sizeof(key));
7129
44fb5511
CM		 7130 /* make sure this block group isn't part of an allocation cluster */
7131 cluster = &root->fs_info->data_alloc_cluster;
7132 spin_lock(&cluster->refill_lock);
7133 btrfs_return_cluster_to_free_space(block_group, cluster);
7134 spin_unlock(&cluster->refill_lock);
7135
7136 /*
7137 * make sure this block group isn't part of a metadata
7138 * allocation cluster
7139 */
7140 cluster = &root->fs_info->meta_alloc_cluster;
7141 spin_lock(&cluster->refill_lock);
7142 btrfs_return_cluster_to_free_space(block_group, cluster);
7143 spin_unlock(&cluster->refill_lock);
7144
1a40e23b
ZY		 7145 path = btrfs_alloc_path();
7146 BUG_ON(!path);
7147
3dfdb934 7148 spin_lock(&root->fs_info->block_group_cache_lock);
1a40e23b
ZY		 7149 rb_erase(&block_group->cache_node,
7150 &root->fs_info->block_group_cache_tree);
3dfdb934
YZ		 7151 spin_unlock(&root->fs_info->block_group_cache_lock);
7152 btrfs_remove_free_space_cache(block_group);
80eb234a 7153 down_write(&block_group->space_info->groups_sem);
44fb5511
CM		 7154 /*
7155 * we must use list_del_init so people can check to see if they
7156 * are still on the list after taking the semaphore
7157 */
7158 list_del_init(&block_group->list);
80eb234a 7159 up_write(&block_group->space_info->groups_sem);
1a40e23b 7160
c146afad
YZ		 7161 spin_lock(&block_group->space_info->lock);
7162 block_group->space_info->total_bytes -= block_group->key.offset;
7163 block_group->space_info->bytes_readonly -= block_group->key.offset;
7164 spin_unlock(&block_group->space_info->lock);
2b82032c 7165 block_group->space_info->full = 0;
c146afad 7166
fa9c0d79
CM		 7167 btrfs_put_block_group(block_group);
7168 btrfs_put_block_group(block_group);
1a40e23b
ZY		 7169
7170 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
7171 if (ret > 0)
7172 ret = -EIO;
7173 if (ret < 0)
7174 goto out;
7175
7176 ret = btrfs_del_item(trans, root, path);
7177out:
7178 btrfs_free_path(path);
7179 return ret;
7180}
Linux kernel - Deliverables
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