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1 | /* | |
2 | * Copyright (C) 2007 Oracle. All rights reserved. | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or | |
5 | * modify it under the terms of the GNU General Public | |
6 | * License v2 as published by the Free Software Foundation. | |
7 | * | |
8 | * This program is distributed in the hope that it will be useful, | |
9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
11 | * General Public License for more details. | |
12 | * | |
13 | * You should have received a copy of the GNU General Public | |
14 | * License along with this program; if not, write to the | |
15 | * Free Software Foundation, Inc., 59 Temple Place - Suite 330, | |
16 | * Boston, MA 021110-1307, USA. | |
17 | */ | |
18 | #include <linux/sched.h> | |
19 | #include <linux/pagemap.h> | |
20 | #include <linux/writeback.h> | |
21 | #include <linux/blkdev.h> | |
22 | #include <linux/sort.h> | |
23 | #include <linux/rcupdate.h> | |
24 | #include <linux/kthread.h> | |
25 | #include <linux/slab.h> | |
26 | #include "compat.h" | |
27 | #include "hash.h" | |
28 | #include "ctree.h" | |
29 | #include "disk-io.h" | |
30 | #include "print-tree.h" | |
31 | #include "transaction.h" | |
32 | #include "volumes.h" | |
33 | #include "locking.h" | |
34 | #include "free-space-cache.h" | |
35 | ||
36 | static int update_block_group(struct btrfs_trans_handle *trans, | |
37 | struct btrfs_root *root, | |
38 | u64 bytenr, u64 num_bytes, int alloc); | |
39 | static int update_reserved_bytes(struct btrfs_block_group_cache *cache, | |
40 | u64 num_bytes, int reserve, int sinfo); | |
41 | static int __btrfs_free_extent(struct btrfs_trans_handle *trans, | |
42 | struct btrfs_root *root, | |
43 | u64 bytenr, u64 num_bytes, u64 parent, | |
44 | u64 root_objectid, u64 owner_objectid, | |
45 | u64 owner_offset, int refs_to_drop, | |
46 | struct btrfs_delayed_extent_op *extra_op); | |
47 | static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op, | |
48 | struct extent_buffer *leaf, | |
49 | struct btrfs_extent_item *ei); | |
50 | static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans, | |
51 | struct btrfs_root *root, | |
52 | u64 parent, u64 root_objectid, | |
53 | u64 flags, u64 owner, u64 offset, | |
54 | struct btrfs_key *ins, int ref_mod); | |
55 | static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans, | |
56 | struct btrfs_root *root, | |
57 | u64 parent, u64 root_objectid, | |
58 | u64 flags, struct btrfs_disk_key *key, | |
59 | int level, struct btrfs_key *ins); | |
60 | static int do_chunk_alloc(struct btrfs_trans_handle *trans, | |
61 | struct btrfs_root *extent_root, u64 alloc_bytes, | |
62 | u64 flags, int force); | |
63 | static int find_next_key(struct btrfs_path *path, int level, | |
64 | struct btrfs_key *key); | |
65 | static void dump_space_info(struct btrfs_space_info *info, u64 bytes, | |
66 | int dump_block_groups); | |
67 | static int maybe_allocate_chunk(struct btrfs_trans_handle *trans, | |
68 | struct btrfs_root *root, | |
69 | struct btrfs_space_info *sinfo, u64 num_bytes); | |
70 | static int shrink_delalloc(struct btrfs_trans_handle *trans, | |
71 | struct btrfs_root *root, | |
72 | struct btrfs_space_info *sinfo, u64 to_reclaim); | |
73 | ||
74 | static noinline int | |
75 | block_group_cache_done(struct btrfs_block_group_cache *cache) | |
76 | { | |
77 | smp_mb(); | |
78 | return cache->cached == BTRFS_CACHE_FINISHED; | |
79 | } | |
80 | ||
81 | static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits) | |
82 | { | |
83 | return (cache->flags & bits) == bits; | |
84 | } | |
85 | ||
86 | void btrfs_get_block_group(struct btrfs_block_group_cache *cache) | |
87 | { | |
88 | atomic_inc(&cache->count); | |
89 | } | |
90 | ||
91 | void btrfs_put_block_group(struct btrfs_block_group_cache *cache) | |
92 | { | |
93 | if (atomic_dec_and_test(&cache->count)) { | |
94 | WARN_ON(cache->pinned > 0); | |
95 | WARN_ON(cache->reserved > 0); | |
96 | WARN_ON(cache->reserved_pinned > 0); | |
97 | kfree(cache); | |
98 | } | |
99 | } | |
100 | ||
101 | /* | |
102 | * this adds the block group to the fs_info rb tree for the block group | |
103 | * cache | |
104 | */ | |
105 | static int btrfs_add_block_group_cache(struct btrfs_fs_info *info, | |
106 | struct btrfs_block_group_cache *block_group) | |
107 | { | |
108 | struct rb_node **p; | |
109 | struct rb_node *parent = NULL; | |
110 | struct btrfs_block_group_cache *cache; | |
111 | ||
112 | spin_lock(&info->block_group_cache_lock); | |
113 | p = &info->block_group_cache_tree.rb_node; | |
114 | ||
115 | while (*p) { | |
116 | parent = *p; | |
117 | cache = rb_entry(parent, struct btrfs_block_group_cache, | |
118 | cache_node); | |
119 | if (block_group->key.objectid < cache->key.objectid) { | |
120 | p = &(*p)->rb_left; | |
121 | } else if (block_group->key.objectid > cache->key.objectid) { | |
122 | p = &(*p)->rb_right; | |
123 | } else { | |
124 | spin_unlock(&info->block_group_cache_lock); | |
125 | return -EEXIST; | |
126 | } | |
127 | } | |
128 | ||
129 | rb_link_node(&block_group->cache_node, parent, p); | |
130 | rb_insert_color(&block_group->cache_node, | |
131 | &info->block_group_cache_tree); | |
132 | spin_unlock(&info->block_group_cache_lock); | |
133 | ||
134 | return 0; | |
135 | } | |
136 | ||
137 | /* | |
138 | * This will return the block group at or after bytenr if contains is 0, else | |
139 | * it will return the block group that contains the bytenr | |
140 | */ | |
141 | static struct btrfs_block_group_cache * | |
142 | block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr, | |
143 | int contains) | |
144 | { | |
145 | struct btrfs_block_group_cache *cache, *ret = NULL; | |
146 | struct rb_node *n; | |
147 | u64 end, start; | |
148 | ||
149 | spin_lock(&info->block_group_cache_lock); | |
150 | n = info->block_group_cache_tree.rb_node; | |
151 | ||
152 | while (n) { | |
153 | cache = rb_entry(n, struct btrfs_block_group_cache, | |
154 | cache_node); | |
155 | end = cache->key.objectid + cache->key.offset - 1; | |
156 | start = cache->key.objectid; | |
157 | ||
158 | if (bytenr < start) { | |
159 | if (!contains && (!ret || start < ret->key.objectid)) | |
160 | ret = cache; | |
161 | n = n->rb_left; | |
162 | } else if (bytenr > start) { | |
163 | if (contains && bytenr <= end) { | |
164 | ret = cache; | |
165 | break; | |
166 | } | |
167 | n = n->rb_right; | |
168 | } else { | |
169 | ret = cache; | |
170 | break; | |
171 | } | |
172 | } | |
173 | if (ret) | |
174 | btrfs_get_block_group(ret); | |
175 | spin_unlock(&info->block_group_cache_lock); | |
176 | ||
177 | return ret; | |
178 | } | |
179 | ||
180 | static int add_excluded_extent(struct btrfs_root *root, | |
181 | u64 start, u64 num_bytes) | |
182 | { | |
183 | u64 end = start + num_bytes - 1; | |
184 | set_extent_bits(&root->fs_info->freed_extents[0], | |
185 | start, end, EXTENT_UPTODATE, GFP_NOFS); | |
186 | set_extent_bits(&root->fs_info->freed_extents[1], | |
187 | start, end, EXTENT_UPTODATE, GFP_NOFS); | |
188 | return 0; | |
189 | } | |
190 | ||
191 | static void free_excluded_extents(struct btrfs_root *root, | |
192 | struct btrfs_block_group_cache *cache) | |
193 | { | |
194 | u64 start, end; | |
195 | ||
196 | start = cache->key.objectid; | |
197 | end = start + cache->key.offset - 1; | |
198 | ||
199 | clear_extent_bits(&root->fs_info->freed_extents[0], | |
200 | start, end, EXTENT_UPTODATE, GFP_NOFS); | |
201 | clear_extent_bits(&root->fs_info->freed_extents[1], | |
202 | start, end, EXTENT_UPTODATE, GFP_NOFS); | |
203 | } | |
204 | ||
205 | static int exclude_super_stripes(struct btrfs_root *root, | |
206 | struct btrfs_block_group_cache *cache) | |
207 | { | |
208 | u64 bytenr; | |
209 | u64 *logical; | |
210 | int stripe_len; | |
211 | int i, nr, ret; | |
212 | ||
213 | if (cache->key.objectid < BTRFS_SUPER_INFO_OFFSET) { | |
214 | stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->key.objectid; | |
215 | cache->bytes_super += stripe_len; | |
216 | ret = add_excluded_extent(root, cache->key.objectid, | |
217 | stripe_len); | |
218 | BUG_ON(ret); | |
219 | } | |
220 | ||
221 | for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) { | |
222 | bytenr = btrfs_sb_offset(i); | |
223 | ret = btrfs_rmap_block(&root->fs_info->mapping_tree, | |
224 | cache->key.objectid, bytenr, | |
225 | 0, &logical, &nr, &stripe_len); | |
226 | BUG_ON(ret); | |
227 | ||
228 | while (nr--) { | |
229 | cache->bytes_super += stripe_len; | |
230 | ret = add_excluded_extent(root, logical[nr], | |
231 | stripe_len); | |
232 | BUG_ON(ret); | |
233 | } | |
234 | ||
235 | kfree(logical); | |
236 | } | |
237 | return 0; | |
238 | } | |
239 | ||
240 | static struct btrfs_caching_control * | |
241 | get_caching_control(struct btrfs_block_group_cache *cache) | |
242 | { | |
243 | struct btrfs_caching_control *ctl; | |
244 | ||
245 | spin_lock(&cache->lock); | |
246 | if (cache->cached != BTRFS_CACHE_STARTED) { | |
247 | spin_unlock(&cache->lock); | |
248 | return NULL; | |
249 | } | |
250 | ||
251 | ctl = cache->caching_ctl; | |
252 | atomic_inc(&ctl->count); | |
253 | spin_unlock(&cache->lock); | |
254 | return ctl; | |
255 | } | |
256 | ||
257 | static void put_caching_control(struct btrfs_caching_control *ctl) | |
258 | { | |
259 | if (atomic_dec_and_test(&ctl->count)) | |
260 | kfree(ctl); | |
261 | } | |
262 | ||
263 | /* | |
264 | * this is only called by cache_block_group, since we could have freed extents | |
265 | * we need to check the pinned_extents for any extents that can't be used yet | |
266 | * since their free space will be released as soon as the transaction commits. | |
267 | */ | |
268 | static u64 add_new_free_space(struct btrfs_block_group_cache *block_group, | |
269 | struct btrfs_fs_info *info, u64 start, u64 end) | |
270 | { | |
271 | u64 extent_start, extent_end, size, total_added = 0; | |
272 | int ret; | |
273 | ||
274 | while (start < end) { | |
275 | ret = find_first_extent_bit(info->pinned_extents, start, | |
276 | &extent_start, &extent_end, | |
277 | EXTENT_DIRTY | EXTENT_UPTODATE); | |
278 | if (ret) | |
279 | break; | |
280 | ||
281 | if (extent_start <= start) { | |
282 | start = extent_end + 1; | |
283 | } else if (extent_start > start && extent_start < end) { | |
284 | size = extent_start - start; | |
285 | total_added += size; | |
286 | ret = btrfs_add_free_space(block_group, start, | |
287 | size); | |
288 | BUG_ON(ret); | |
289 | start = extent_end + 1; | |
290 | } else { | |
291 | break; | |
292 | } | |
293 | } | |
294 | ||
295 | if (start < end) { | |
296 | size = end - start; | |
297 | total_added += size; | |
298 | ret = btrfs_add_free_space(block_group, start, size); | |
299 | BUG_ON(ret); | |
300 | } | |
301 | ||
302 | return total_added; | |
303 | } | |
304 | ||
305 | static int caching_kthread(void *data) | |
306 | { | |
307 | struct btrfs_block_group_cache *block_group = data; | |
308 | struct btrfs_fs_info *fs_info = block_group->fs_info; | |
309 | struct btrfs_caching_control *caching_ctl = block_group->caching_ctl; | |
310 | struct btrfs_root *extent_root = fs_info->extent_root; | |
311 | struct btrfs_path *path; | |
312 | struct extent_buffer *leaf; | |
313 | struct btrfs_key key; | |
314 | u64 total_found = 0; | |
315 | u64 last = 0; | |
316 | u32 nritems; | |
317 | int ret = 0; | |
318 | ||
319 | path = btrfs_alloc_path(); | |
320 | if (!path) | |
321 | return -ENOMEM; | |
322 | ||
323 | exclude_super_stripes(extent_root, block_group); | |
324 | spin_lock(&block_group->space_info->lock); | |
325 | block_group->space_info->bytes_readonly += block_group->bytes_super; | |
326 | spin_unlock(&block_group->space_info->lock); | |
327 | ||
328 | last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET); | |
329 | ||
330 | /* | |
331 | * We don't want to deadlock with somebody trying to allocate a new | |
332 | * extent for the extent root while also trying to search the extent | |
333 | * root to add free space. So we skip locking and search the commit | |
334 | * root, since its read-only | |
335 | */ | |
336 | path->skip_locking = 1; | |
337 | path->search_commit_root = 1; | |
338 | path->reada = 2; | |
339 | ||
340 | key.objectid = last; | |
341 | key.offset = 0; | |
342 | key.type = BTRFS_EXTENT_ITEM_KEY; | |
343 | again: | |
344 | mutex_lock(&caching_ctl->mutex); | |
345 | /* need to make sure the commit_root doesn't disappear */ | |
346 | down_read(&fs_info->extent_commit_sem); | |
347 | ||
348 | ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0); | |
349 | if (ret < 0) | |
350 | goto err; | |
351 | ||
352 | leaf = path->nodes[0]; | |
353 | nritems = btrfs_header_nritems(leaf); | |
354 | ||
355 | while (1) { | |
356 | smp_mb(); | |
357 | if (fs_info->closing > 1) { | |
358 | last = (u64)-1; | |
359 | break; | |
360 | } | |
361 | ||
362 | if (path->slots[0] < nritems) { | |
363 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
364 | } else { | |
365 | ret = find_next_key(path, 0, &key); | |
366 | if (ret) | |
367 | break; | |
368 | ||
369 | caching_ctl->progress = last; | |
370 | btrfs_release_path(extent_root, path); | |
371 | up_read(&fs_info->extent_commit_sem); | |
372 | mutex_unlock(&caching_ctl->mutex); | |
373 | if (btrfs_transaction_in_commit(fs_info)) | |
374 | schedule_timeout(1); | |
375 | else | |
376 | cond_resched(); | |
377 | goto again; | |
378 | } | |
379 | ||
380 | if (key.objectid < block_group->key.objectid) { | |
381 | path->slots[0]++; | |
382 | continue; | |
383 | } | |
384 | ||
385 | if (key.objectid >= block_group->key.objectid + | |
386 | block_group->key.offset) | |
387 | break; | |
388 | ||
389 | if (key.type == BTRFS_EXTENT_ITEM_KEY) { | |
390 | total_found += add_new_free_space(block_group, | |
391 | fs_info, last, | |
392 | key.objectid); | |
393 | last = key.objectid + key.offset; | |
394 | ||
395 | if (total_found > (1024 * 1024 * 2)) { | |
396 | total_found = 0; | |
397 | wake_up(&caching_ctl->wait); | |
398 | } | |
399 | } | |
400 | path->slots[0]++; | |
401 | } | |
402 | ret = 0; | |
403 | ||
404 | total_found += add_new_free_space(block_group, fs_info, last, | |
405 | block_group->key.objectid + | |
406 | block_group->key.offset); | |
407 | caching_ctl->progress = (u64)-1; | |
408 | ||
409 | spin_lock(&block_group->lock); | |
410 | block_group->caching_ctl = NULL; | |
411 | block_group->cached = BTRFS_CACHE_FINISHED; | |
412 | spin_unlock(&block_group->lock); | |
413 | ||
414 | err: | |
415 | btrfs_free_path(path); | |
416 | up_read(&fs_info->extent_commit_sem); | |
417 | ||
418 | free_excluded_extents(extent_root, block_group); | |
419 | ||
420 | mutex_unlock(&caching_ctl->mutex); | |
421 | wake_up(&caching_ctl->wait); | |
422 | ||
423 | put_caching_control(caching_ctl); | |
424 | atomic_dec(&block_group->space_info->caching_threads); | |
425 | btrfs_put_block_group(block_group); | |
426 | ||
427 | return 0; | |
428 | } | |
429 | ||
430 | static int cache_block_group(struct btrfs_block_group_cache *cache) | |
431 | { | |
432 | struct btrfs_fs_info *fs_info = cache->fs_info; | |
433 | struct btrfs_caching_control *caching_ctl; | |
434 | struct task_struct *tsk; | |
435 | int ret = 0; | |
436 | ||
437 | smp_mb(); | |
438 | if (cache->cached != BTRFS_CACHE_NO) | |
439 | return 0; | |
440 | ||
441 | caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_KERNEL); | |
442 | BUG_ON(!caching_ctl); | |
443 | ||
444 | INIT_LIST_HEAD(&caching_ctl->list); | |
445 | mutex_init(&caching_ctl->mutex); | |
446 | init_waitqueue_head(&caching_ctl->wait); | |
447 | caching_ctl->block_group = cache; | |
448 | caching_ctl->progress = cache->key.objectid; | |
449 | /* one for caching kthread, one for caching block group list */ | |
450 | atomic_set(&caching_ctl->count, 2); | |
451 | ||
452 | spin_lock(&cache->lock); | |
453 | if (cache->cached != BTRFS_CACHE_NO) { | |
454 | spin_unlock(&cache->lock); | |
455 | kfree(caching_ctl); | |
456 | return 0; | |
457 | } | |
458 | cache->caching_ctl = caching_ctl; | |
459 | cache->cached = BTRFS_CACHE_STARTED; | |
460 | spin_unlock(&cache->lock); | |
461 | ||
462 | down_write(&fs_info->extent_commit_sem); | |
463 | list_add_tail(&caching_ctl->list, &fs_info->caching_block_groups); | |
464 | up_write(&fs_info->extent_commit_sem); | |
465 | ||
466 | atomic_inc(&cache->space_info->caching_threads); | |
467 | btrfs_get_block_group(cache); | |
468 | ||
469 | tsk = kthread_run(caching_kthread, cache, "btrfs-cache-%llu\n", | |
470 | cache->key.objectid); | |
471 | if (IS_ERR(tsk)) { | |
472 | ret = PTR_ERR(tsk); | |
473 | printk(KERN_ERR "error running thread %d\n", ret); | |
474 | BUG(); | |
475 | } | |
476 | ||
477 | return ret; | |
478 | } | |
479 | ||
480 | /* | |
481 | * return the block group that starts at or after bytenr | |
482 | */ | |
483 | static struct btrfs_block_group_cache * | |
484 | btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr) | |
485 | { | |
486 | struct btrfs_block_group_cache *cache; | |
487 | ||
488 | cache = block_group_cache_tree_search(info, bytenr, 0); | |
489 | ||
490 | return cache; | |
491 | } | |
492 | ||
493 | /* | |
494 | * return the block group that contains the given bytenr | |
495 | */ | |
496 | struct btrfs_block_group_cache *btrfs_lookup_block_group( | |
497 | struct btrfs_fs_info *info, | |
498 | u64 bytenr) | |
499 | { | |
500 | struct btrfs_block_group_cache *cache; | |
501 | ||
502 | cache = block_group_cache_tree_search(info, bytenr, 1); | |
503 | ||
504 | return cache; | |
505 | } | |
506 | ||
507 | static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info, | |
508 | u64 flags) | |
509 | { | |
510 | struct list_head *head = &info->space_info; | |
511 | struct btrfs_space_info *found; | |
512 | ||
513 | flags &= BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_SYSTEM | | |
514 | BTRFS_BLOCK_GROUP_METADATA; | |
515 | ||
516 | rcu_read_lock(); | |
517 | list_for_each_entry_rcu(found, head, list) { | |
518 | if (found->flags == flags) { | |
519 | rcu_read_unlock(); | |
520 | return found; | |
521 | } | |
522 | } | |
523 | rcu_read_unlock(); | |
524 | return NULL; | |
525 | } | |
526 | ||
527 | /* | |
528 | * after adding space to the filesystem, we need to clear the full flags | |
529 | * on all the space infos. | |
530 | */ | |
531 | void btrfs_clear_space_info_full(struct btrfs_fs_info *info) | |
532 | { | |
533 | struct list_head *head = &info->space_info; | |
534 | struct btrfs_space_info *found; | |
535 | ||
536 | rcu_read_lock(); | |
537 | list_for_each_entry_rcu(found, head, list) | |
538 | found->full = 0; | |
539 | rcu_read_unlock(); | |
540 | } | |
541 | ||
542 | static u64 div_factor(u64 num, int factor) | |
543 | { | |
544 | if (factor == 10) | |
545 | return num; | |
546 | num *= factor; | |
547 | do_div(num, 10); | |
548 | return num; | |
549 | } | |
550 | ||
551 | u64 btrfs_find_block_group(struct btrfs_root *root, | |
552 | u64 search_start, u64 search_hint, int owner) | |
553 | { | |
554 | struct btrfs_block_group_cache *cache; | |
555 | u64 used; | |
556 | u64 last = max(search_hint, search_start); | |
557 | u64 group_start = 0; | |
558 | int full_search = 0; | |
559 | int factor = 9; | |
560 | int wrapped = 0; | |
561 | again: | |
562 | while (1) { | |
563 | cache = btrfs_lookup_first_block_group(root->fs_info, last); | |
564 | if (!cache) | |
565 | break; | |
566 | ||
567 | spin_lock(&cache->lock); | |
568 | last = cache->key.objectid + cache->key.offset; | |
569 | used = btrfs_block_group_used(&cache->item); | |
570 | ||
571 | if ((full_search || !cache->ro) && | |
572 | block_group_bits(cache, BTRFS_BLOCK_GROUP_METADATA)) { | |
573 | if (used + cache->pinned + cache->reserved < | |
574 | div_factor(cache->key.offset, factor)) { | |
575 | group_start = cache->key.objectid; | |
576 | spin_unlock(&cache->lock); | |
577 | btrfs_put_block_group(cache); | |
578 | goto found; | |
579 | } | |
580 | } | |
581 | spin_unlock(&cache->lock); | |
582 | btrfs_put_block_group(cache); | |
583 | cond_resched(); | |
584 | } | |
585 | if (!wrapped) { | |
586 | last = search_start; | |
587 | wrapped = 1; | |
588 | goto again; | |
589 | } | |
590 | if (!full_search && factor < 10) { | |
591 | last = search_start; | |
592 | full_search = 1; | |
593 | factor = 10; | |
594 | goto again; | |
595 | } | |
596 | found: | |
597 | return group_start; | |
598 | } | |
599 | ||
600 | /* simple helper to search for an existing extent at a given offset */ | |
601 | int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len) | |
602 | { | |
603 | int ret; | |
604 | struct btrfs_key key; | |
605 | struct btrfs_path *path; | |
606 | ||
607 | path = btrfs_alloc_path(); | |
608 | BUG_ON(!path); | |
609 | key.objectid = start; | |
610 | key.offset = len; | |
611 | btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); | |
612 | ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path, | |
613 | 0, 0); | |
614 | btrfs_free_path(path); | |
615 | return ret; | |
616 | } | |
617 | ||
618 | /* | |
619 | * helper function to lookup reference count and flags of extent. | |
620 | * | |
621 | * the head node for delayed ref is used to store the sum of all the | |
622 | * reference count modifications queued up in the rbtree. the head | |
623 | * node may also store the extent flags to set. This way you can check | |
624 | * to see what the reference count and extent flags would be if all of | |
625 | * the delayed refs are not processed. | |
626 | */ | |
627 | int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans, | |
628 | struct btrfs_root *root, u64 bytenr, | |
629 | u64 num_bytes, u64 *refs, u64 *flags) | |
630 | { | |
631 | struct btrfs_delayed_ref_head *head; | |
632 | struct btrfs_delayed_ref_root *delayed_refs; | |
633 | struct btrfs_path *path; | |
634 | struct btrfs_extent_item *ei; | |
635 | struct extent_buffer *leaf; | |
636 | struct btrfs_key key; | |
637 | u32 item_size; | |
638 | u64 num_refs; | |
639 | u64 extent_flags; | |
640 | int ret; | |
641 | ||
642 | path = btrfs_alloc_path(); | |
643 | if (!path) | |
644 | return -ENOMEM; | |
645 | ||
646 | key.objectid = bytenr; | |
647 | key.type = BTRFS_EXTENT_ITEM_KEY; | |
648 | key.offset = num_bytes; | |
649 | if (!trans) { | |
650 | path->skip_locking = 1; | |
651 | path->search_commit_root = 1; | |
652 | } | |
653 | again: | |
654 | ret = btrfs_search_slot(trans, root->fs_info->extent_root, | |
655 | &key, path, 0, 0); | |
656 | if (ret < 0) | |
657 | goto out_free; | |
658 | ||
659 | if (ret == 0) { | |
660 | leaf = path->nodes[0]; | |
661 | item_size = btrfs_item_size_nr(leaf, path->slots[0]); | |
662 | if (item_size >= sizeof(*ei)) { | |
663 | ei = btrfs_item_ptr(leaf, path->slots[0], | |
664 | struct btrfs_extent_item); | |
665 | num_refs = btrfs_extent_refs(leaf, ei); | |
666 | extent_flags = btrfs_extent_flags(leaf, ei); | |
667 | } else { | |
668 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
669 | struct btrfs_extent_item_v0 *ei0; | |
670 | BUG_ON(item_size != sizeof(*ei0)); | |
671 | ei0 = btrfs_item_ptr(leaf, path->slots[0], | |
672 | struct btrfs_extent_item_v0); | |
673 | num_refs = btrfs_extent_refs_v0(leaf, ei0); | |
674 | /* FIXME: this isn't correct for data */ | |
675 | extent_flags = BTRFS_BLOCK_FLAG_FULL_BACKREF; | |
676 | #else | |
677 | BUG(); | |
678 | #endif | |
679 | } | |
680 | BUG_ON(num_refs == 0); | |
681 | } else { | |
682 | num_refs = 0; | |
683 | extent_flags = 0; | |
684 | ret = 0; | |
685 | } | |
686 | ||
687 | if (!trans) | |
688 | goto out; | |
689 | ||
690 | delayed_refs = &trans->transaction->delayed_refs; | |
691 | spin_lock(&delayed_refs->lock); | |
692 | head = btrfs_find_delayed_ref_head(trans, bytenr); | |
693 | if (head) { | |
694 | if (!mutex_trylock(&head->mutex)) { | |
695 | atomic_inc(&head->node.refs); | |
696 | spin_unlock(&delayed_refs->lock); | |
697 | ||
698 | btrfs_release_path(root->fs_info->extent_root, path); | |
699 | ||
700 | mutex_lock(&head->mutex); | |
701 | mutex_unlock(&head->mutex); | |
702 | btrfs_put_delayed_ref(&head->node); | |
703 | goto again; | |
704 | } | |
705 | if (head->extent_op && head->extent_op->update_flags) | |
706 | extent_flags |= head->extent_op->flags_to_set; | |
707 | else | |
708 | BUG_ON(num_refs == 0); | |
709 | ||
710 | num_refs += head->node.ref_mod; | |
711 | mutex_unlock(&head->mutex); | |
712 | } | |
713 | spin_unlock(&delayed_refs->lock); | |
714 | out: | |
715 | WARN_ON(num_refs == 0); | |
716 | if (refs) | |
717 | *refs = num_refs; | |
718 | if (flags) | |
719 | *flags = extent_flags; | |
720 | out_free: | |
721 | btrfs_free_path(path); | |
722 | return ret; | |
723 | } | |
724 | ||
725 | /* | |
726 | * Back reference rules. Back refs have three main goals: | |
727 | * | |
728 | * 1) differentiate between all holders of references to an extent so that | |
729 | * when a reference is dropped we can make sure it was a valid reference | |
730 | * before freeing the extent. | |
731 | * | |
732 | * 2) Provide enough information to quickly find the holders of an extent | |
733 | * if we notice a given block is corrupted or bad. | |
734 | * | |
735 | * 3) Make it easy to migrate blocks for FS shrinking or storage pool | |
736 | * maintenance. This is actually the same as #2, but with a slightly | |
737 | * different use case. | |
738 | * | |
739 | * There are two kinds of back refs. The implicit back refs is optimized | |
740 | * for pointers in non-shared tree blocks. For a given pointer in a block, | |
741 | * back refs of this kind provide information about the block's owner tree | |
742 | * and the pointer's key. These information allow us to find the block by | |
743 | * b-tree searching. The full back refs is for pointers in tree blocks not | |
744 | * referenced by their owner trees. The location of tree block is recorded | |
745 | * in the back refs. Actually the full back refs is generic, and can be | |
746 | * used in all cases the implicit back refs is used. The major shortcoming | |
747 | * of the full back refs is its overhead. Every time a tree block gets | |
748 | * COWed, we have to update back refs entry for all pointers in it. | |
749 | * | |
750 | * For a newly allocated tree block, we use implicit back refs for | |
751 | * pointers in it. This means most tree related operations only involve | |
752 | * implicit back refs. For a tree block created in old transaction, the | |
753 | * only way to drop a reference to it is COW it. So we can detect the | |
754 | * event that tree block loses its owner tree's reference and do the | |
755 | * back refs conversion. | |
756 | * | |
757 | * When a tree block is COW'd through a tree, there are four cases: | |
758 | * | |
759 | * The reference count of the block is one and the tree is the block's | |
760 | * owner tree. Nothing to do in this case. | |
761 | * | |
762 | * The reference count of the block is one and the tree is not the | |
763 | * block's owner tree. In this case, full back refs is used for pointers | |
764 | * in the block. Remove these full back refs, add implicit back refs for | |
765 | * every pointers in the new block. | |
766 | * | |
767 | * The reference count of the block is greater than one and the tree is | |
768 | * the block's owner tree. In this case, implicit back refs is used for | |
769 | * pointers in the block. Add full back refs for every pointers in the | |
770 | * block, increase lower level extents' reference counts. The original | |
771 | * implicit back refs are entailed to the new block. | |
772 | * | |
773 | * The reference count of the block is greater than one and the tree is | |
774 | * not the block's owner tree. Add implicit back refs for every pointer in | |
775 | * the new block, increase lower level extents' reference count. | |
776 | * | |
777 | * Back Reference Key composing: | |
778 | * | |
779 | * The key objectid corresponds to the first byte in the extent, | |
780 | * The key type is used to differentiate between types of back refs. | |
781 | * There are different meanings of the key offset for different types | |
782 | * of back refs. | |
783 | * | |
784 | * File extents can be referenced by: | |
785 | * | |
786 | * - multiple snapshots, subvolumes, or different generations in one subvol | |
787 | * - different files inside a single subvolume | |
788 | * - different offsets inside a file (bookend extents in file.c) | |
789 | * | |
790 | * The extent ref structure for the implicit back refs has fields for: | |
791 | * | |
792 | * - Objectid of the subvolume root | |
793 | * - objectid of the file holding the reference | |
794 | * - original offset in the file | |
795 | * - how many bookend extents | |
796 | * | |
797 | * The key offset for the implicit back refs is hash of the first | |
798 | * three fields. | |
799 | * | |
800 | * The extent ref structure for the full back refs has field for: | |
801 | * | |
802 | * - number of pointers in the tree leaf | |
803 | * | |
804 | * The key offset for the implicit back refs is the first byte of | |
805 | * the tree leaf | |
806 | * | |
807 | * When a file extent is allocated, The implicit back refs is used. | |
808 | * the fields are filled in: | |
809 | * | |
810 | * (root_key.objectid, inode objectid, offset in file, 1) | |
811 | * | |
812 | * When a file extent is removed file truncation, we find the | |
813 | * corresponding implicit back refs and check the following fields: | |
814 | * | |
815 | * (btrfs_header_owner(leaf), inode objectid, offset in file) | |
816 | * | |
817 | * Btree extents can be referenced by: | |
818 | * | |
819 | * - Different subvolumes | |
820 | * | |
821 | * Both the implicit back refs and the full back refs for tree blocks | |
822 | * only consist of key. The key offset for the implicit back refs is | |
823 | * objectid of block's owner tree. The key offset for the full back refs | |
824 | * is the first byte of parent block. | |
825 | * | |
826 | * When implicit back refs is used, information about the lowest key and | |
827 | * level of the tree block are required. These information are stored in | |
828 | * tree block info structure. | |
829 | */ | |
830 | ||
831 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
832 | static int convert_extent_item_v0(struct btrfs_trans_handle *trans, | |
833 | struct btrfs_root *root, | |
834 | struct btrfs_path *path, | |
835 | u64 owner, u32 extra_size) | |
836 | { | |
837 | struct btrfs_extent_item *item; | |
838 | struct btrfs_extent_item_v0 *ei0; | |
839 | struct btrfs_extent_ref_v0 *ref0; | |
840 | struct btrfs_tree_block_info *bi; | |
841 | struct extent_buffer *leaf; | |
842 | struct btrfs_key key; | |
843 | struct btrfs_key found_key; | |
844 | u32 new_size = sizeof(*item); | |
845 | u64 refs; | |
846 | int ret; | |
847 | ||
848 | leaf = path->nodes[0]; | |
849 | BUG_ON(btrfs_item_size_nr(leaf, path->slots[0]) != sizeof(*ei0)); | |
850 | ||
851 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
852 | ei0 = btrfs_item_ptr(leaf, path->slots[0], | |
853 | struct btrfs_extent_item_v0); | |
854 | refs = btrfs_extent_refs_v0(leaf, ei0); | |
855 | ||
856 | if (owner == (u64)-1) { | |
857 | while (1) { | |
858 | if (path->slots[0] >= btrfs_header_nritems(leaf)) { | |
859 | ret = btrfs_next_leaf(root, path); | |
860 | if (ret < 0) | |
861 | return ret; | |
862 | BUG_ON(ret > 0); | |
863 | leaf = path->nodes[0]; | |
864 | } | |
865 | btrfs_item_key_to_cpu(leaf, &found_key, | |
866 | path->slots[0]); | |
867 | BUG_ON(key.objectid != found_key.objectid); | |
868 | if (found_key.type != BTRFS_EXTENT_REF_V0_KEY) { | |
869 | path->slots[0]++; | |
870 | continue; | |
871 | } | |
872 | ref0 = btrfs_item_ptr(leaf, path->slots[0], | |
873 | struct btrfs_extent_ref_v0); | |
874 | owner = btrfs_ref_objectid_v0(leaf, ref0); | |
875 | break; | |
876 | } | |
877 | } | |
878 | btrfs_release_path(root, path); | |
879 | ||
880 | if (owner < BTRFS_FIRST_FREE_OBJECTID) | |
881 | new_size += sizeof(*bi); | |
882 | ||
883 | new_size -= sizeof(*ei0); | |
884 | ret = btrfs_search_slot(trans, root, &key, path, | |
885 | new_size + extra_size, 1); | |
886 | if (ret < 0) | |
887 | return ret; | |
888 | BUG_ON(ret); | |
889 | ||
890 | ret = btrfs_extend_item(trans, root, path, new_size); | |
891 | BUG_ON(ret); | |
892 | ||
893 | leaf = path->nodes[0]; | |
894 | item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item); | |
895 | btrfs_set_extent_refs(leaf, item, refs); | |
896 | /* FIXME: get real generation */ | |
897 | btrfs_set_extent_generation(leaf, item, 0); | |
898 | if (owner < BTRFS_FIRST_FREE_OBJECTID) { | |
899 | btrfs_set_extent_flags(leaf, item, | |
900 | BTRFS_EXTENT_FLAG_TREE_BLOCK | | |
901 | BTRFS_BLOCK_FLAG_FULL_BACKREF); | |
902 | bi = (struct btrfs_tree_block_info *)(item + 1); | |
903 | /* FIXME: get first key of the block */ | |
904 | memset_extent_buffer(leaf, 0, (unsigned long)bi, sizeof(*bi)); | |
905 | btrfs_set_tree_block_level(leaf, bi, (int)owner); | |
906 | } else { | |
907 | btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_DATA); | |
908 | } | |
909 | btrfs_mark_buffer_dirty(leaf); | |
910 | return 0; | |
911 | } | |
912 | #endif | |
913 | ||
914 | static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset) | |
915 | { | |
916 | u32 high_crc = ~(u32)0; | |
917 | u32 low_crc = ~(u32)0; | |
918 | __le64 lenum; | |
919 | ||
920 | lenum = cpu_to_le64(root_objectid); | |
921 | high_crc = crc32c(high_crc, &lenum, sizeof(lenum)); | |
922 | lenum = cpu_to_le64(owner); | |
923 | low_crc = crc32c(low_crc, &lenum, sizeof(lenum)); | |
924 | lenum = cpu_to_le64(offset); | |
925 | low_crc = crc32c(low_crc, &lenum, sizeof(lenum)); | |
926 | ||
927 | return ((u64)high_crc << 31) ^ (u64)low_crc; | |
928 | } | |
929 | ||
930 | static u64 hash_extent_data_ref_item(struct extent_buffer *leaf, | |
931 | struct btrfs_extent_data_ref *ref) | |
932 | { | |
933 | return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref), | |
934 | btrfs_extent_data_ref_objectid(leaf, ref), | |
935 | btrfs_extent_data_ref_offset(leaf, ref)); | |
936 | } | |
937 | ||
938 | static int match_extent_data_ref(struct extent_buffer *leaf, | |
939 | struct btrfs_extent_data_ref *ref, | |
940 | u64 root_objectid, u64 owner, u64 offset) | |
941 | { | |
942 | if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid || | |
943 | btrfs_extent_data_ref_objectid(leaf, ref) != owner || | |
944 | btrfs_extent_data_ref_offset(leaf, ref) != offset) | |
945 | return 0; | |
946 | return 1; | |
947 | } | |
948 | ||
949 | static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans, | |
950 | struct btrfs_root *root, | |
951 | struct btrfs_path *path, | |
952 | u64 bytenr, u64 parent, | |
953 | u64 root_objectid, | |
954 | u64 owner, u64 offset) | |
955 | { | |
956 | struct btrfs_key key; | |
957 | struct btrfs_extent_data_ref *ref; | |
958 | struct extent_buffer *leaf; | |
959 | u32 nritems; | |
960 | int ret; | |
961 | int recow; | |
962 | int err = -ENOENT; | |
963 | ||
964 | key.objectid = bytenr; | |
965 | if (parent) { | |
966 | key.type = BTRFS_SHARED_DATA_REF_KEY; | |
967 | key.offset = parent; | |
968 | } else { | |
969 | key.type = BTRFS_EXTENT_DATA_REF_KEY; | |
970 | key.offset = hash_extent_data_ref(root_objectid, | |
971 | owner, offset); | |
972 | } | |
973 | again: | |
974 | recow = 0; | |
975 | ret = btrfs_search_slot(trans, root, &key, path, -1, 1); | |
976 | if (ret < 0) { | |
977 | err = ret; | |
978 | goto fail; | |
979 | } | |
980 | ||
981 | if (parent) { | |
982 | if (!ret) | |
983 | return 0; | |
984 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
985 | key.type = BTRFS_EXTENT_REF_V0_KEY; | |
986 | btrfs_release_path(root, path); | |
987 | ret = btrfs_search_slot(trans, root, &key, path, -1, 1); | |
988 | if (ret < 0) { | |
989 | err = ret; | |
990 | goto fail; | |
991 | } | |
992 | if (!ret) | |
993 | return 0; | |
994 | #endif | |
995 | goto fail; | |
996 | } | |
997 | ||
998 | leaf = path->nodes[0]; | |
999 | nritems = btrfs_header_nritems(leaf); | |
1000 | while (1) { | |
1001 | if (path->slots[0] >= nritems) { | |
1002 | ret = btrfs_next_leaf(root, path); | |
1003 | if (ret < 0) | |
1004 | err = ret; | |
1005 | if (ret) | |
1006 | goto fail; | |
1007 | ||
1008 | leaf = path->nodes[0]; | |
1009 | nritems = btrfs_header_nritems(leaf); | |
1010 | recow = 1; | |
1011 | } | |
1012 | ||
1013 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
1014 | if (key.objectid != bytenr || | |
1015 | key.type != BTRFS_EXTENT_DATA_REF_KEY) | |
1016 | goto fail; | |
1017 | ||
1018 | ref = btrfs_item_ptr(leaf, path->slots[0], | |
1019 | struct btrfs_extent_data_ref); | |
1020 | ||
1021 | if (match_extent_data_ref(leaf, ref, root_objectid, | |
1022 | owner, offset)) { | |
1023 | if (recow) { | |
1024 | btrfs_release_path(root, path); | |
1025 | goto again; | |
1026 | } | |
1027 | err = 0; | |
1028 | break; | |
1029 | } | |
1030 | path->slots[0]++; | |
1031 | } | |
1032 | fail: | |
1033 | return err; | |
1034 | } | |
1035 | ||
1036 | static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans, | |
1037 | struct btrfs_root *root, | |
1038 | struct btrfs_path *path, | |
1039 | u64 bytenr, u64 parent, | |
1040 | u64 root_objectid, u64 owner, | |
1041 | u64 offset, int refs_to_add) | |
1042 | { | |
1043 | struct btrfs_key key; | |
1044 | struct extent_buffer *leaf; | |
1045 | u32 size; | |
1046 | u32 num_refs; | |
1047 | int ret; | |
1048 | ||
1049 | key.objectid = bytenr; | |
1050 | if (parent) { | |
1051 | key.type = BTRFS_SHARED_DATA_REF_KEY; | |
1052 | key.offset = parent; | |
1053 | size = sizeof(struct btrfs_shared_data_ref); | |
1054 | } else { | |
1055 | key.type = BTRFS_EXTENT_DATA_REF_KEY; | |
1056 | key.offset = hash_extent_data_ref(root_objectid, | |
1057 | owner, offset); | |
1058 | size = sizeof(struct btrfs_extent_data_ref); | |
1059 | } | |
1060 | ||
1061 | ret = btrfs_insert_empty_item(trans, root, path, &key, size); | |
1062 | if (ret && ret != -EEXIST) | |
1063 | goto fail; | |
1064 | ||
1065 | leaf = path->nodes[0]; | |
1066 | if (parent) { | |
1067 | struct btrfs_shared_data_ref *ref; | |
1068 | ref = btrfs_item_ptr(leaf, path->slots[0], | |
1069 | struct btrfs_shared_data_ref); | |
1070 | if (ret == 0) { | |
1071 | btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add); | |
1072 | } else { | |
1073 | num_refs = btrfs_shared_data_ref_count(leaf, ref); | |
1074 | num_refs += refs_to_add; | |
1075 | btrfs_set_shared_data_ref_count(leaf, ref, num_refs); | |
1076 | } | |
1077 | } else { | |
1078 | struct btrfs_extent_data_ref *ref; | |
1079 | while (ret == -EEXIST) { | |
1080 | ref = btrfs_item_ptr(leaf, path->slots[0], | |
1081 | struct btrfs_extent_data_ref); | |
1082 | if (match_extent_data_ref(leaf, ref, root_objectid, | |
1083 | owner, offset)) | |
1084 | break; | |
1085 | btrfs_release_path(root, path); | |
1086 | key.offset++; | |
1087 | ret = btrfs_insert_empty_item(trans, root, path, &key, | |
1088 | size); | |
1089 | if (ret && ret != -EEXIST) | |
1090 | goto fail; | |
1091 | ||
1092 | leaf = path->nodes[0]; | |
1093 | } | |
1094 | ref = btrfs_item_ptr(leaf, path->slots[0], | |
1095 | struct btrfs_extent_data_ref); | |
1096 | if (ret == 0) { | |
1097 | btrfs_set_extent_data_ref_root(leaf, ref, | |
1098 | root_objectid); | |
1099 | btrfs_set_extent_data_ref_objectid(leaf, ref, owner); | |
1100 | btrfs_set_extent_data_ref_offset(leaf, ref, offset); | |
1101 | btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add); | |
1102 | } else { | |
1103 | num_refs = btrfs_extent_data_ref_count(leaf, ref); | |
1104 | num_refs += refs_to_add; | |
1105 | btrfs_set_extent_data_ref_count(leaf, ref, num_refs); | |
1106 | } | |
1107 | } | |
1108 | btrfs_mark_buffer_dirty(leaf); | |
1109 | ret = 0; | |
1110 | fail: | |
1111 | btrfs_release_path(root, path); | |
1112 | return ret; | |
1113 | } | |
1114 | ||
1115 | static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans, | |
1116 | struct btrfs_root *root, | |
1117 | struct btrfs_path *path, | |
1118 | int refs_to_drop) | |
1119 | { | |
1120 | struct btrfs_key key; | |
1121 | struct btrfs_extent_data_ref *ref1 = NULL; | |
1122 | struct btrfs_shared_data_ref *ref2 = NULL; | |
1123 | struct extent_buffer *leaf; | |
1124 | u32 num_refs = 0; | |
1125 | int ret = 0; | |
1126 | ||
1127 | leaf = path->nodes[0]; | |
1128 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
1129 | ||
1130 | if (key.type == BTRFS_EXTENT_DATA_REF_KEY) { | |
1131 | ref1 = btrfs_item_ptr(leaf, path->slots[0], | |
1132 | struct btrfs_extent_data_ref); | |
1133 | num_refs = btrfs_extent_data_ref_count(leaf, ref1); | |
1134 | } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) { | |
1135 | ref2 = btrfs_item_ptr(leaf, path->slots[0], | |
1136 | struct btrfs_shared_data_ref); | |
1137 | num_refs = btrfs_shared_data_ref_count(leaf, ref2); | |
1138 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
1139 | } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) { | |
1140 | struct btrfs_extent_ref_v0 *ref0; | |
1141 | ref0 = btrfs_item_ptr(leaf, path->slots[0], | |
1142 | struct btrfs_extent_ref_v0); | |
1143 | num_refs = btrfs_ref_count_v0(leaf, ref0); | |
1144 | #endif | |
1145 | } else { | |
1146 | BUG(); | |
1147 | } | |
1148 | ||
1149 | BUG_ON(num_refs < refs_to_drop); | |
1150 | num_refs -= refs_to_drop; | |
1151 | ||
1152 | if (num_refs == 0) { | |
1153 | ret = btrfs_del_item(trans, root, path); | |
1154 | } else { | |
1155 | if (key.type == BTRFS_EXTENT_DATA_REF_KEY) | |
1156 | btrfs_set_extent_data_ref_count(leaf, ref1, num_refs); | |
1157 | else if (key.type == BTRFS_SHARED_DATA_REF_KEY) | |
1158 | btrfs_set_shared_data_ref_count(leaf, ref2, num_refs); | |
1159 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
1160 | else { | |
1161 | struct btrfs_extent_ref_v0 *ref0; | |
1162 | ref0 = btrfs_item_ptr(leaf, path->slots[0], | |
1163 | struct btrfs_extent_ref_v0); | |
1164 | btrfs_set_ref_count_v0(leaf, ref0, num_refs); | |
1165 | } | |
1166 | #endif | |
1167 | btrfs_mark_buffer_dirty(leaf); | |
1168 | } | |
1169 | return ret; | |
1170 | } | |
1171 | ||
1172 | static noinline u32 extent_data_ref_count(struct btrfs_root *root, | |
1173 | struct btrfs_path *path, | |
1174 | struct btrfs_extent_inline_ref *iref) | |
1175 | { | |
1176 | struct btrfs_key key; | |
1177 | struct extent_buffer *leaf; | |
1178 | struct btrfs_extent_data_ref *ref1; | |
1179 | struct btrfs_shared_data_ref *ref2; | |
1180 | u32 num_refs = 0; | |
1181 | ||
1182 | leaf = path->nodes[0]; | |
1183 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
1184 | if (iref) { | |
1185 | if (btrfs_extent_inline_ref_type(leaf, iref) == | |
1186 | BTRFS_EXTENT_DATA_REF_KEY) { | |
1187 | ref1 = (struct btrfs_extent_data_ref *)(&iref->offset); | |
1188 | num_refs = btrfs_extent_data_ref_count(leaf, ref1); | |
1189 | } else { | |
1190 | ref2 = (struct btrfs_shared_data_ref *)(iref + 1); | |
1191 | num_refs = btrfs_shared_data_ref_count(leaf, ref2); | |
1192 | } | |
1193 | } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) { | |
1194 | ref1 = btrfs_item_ptr(leaf, path->slots[0], | |
1195 | struct btrfs_extent_data_ref); | |
1196 | num_refs = btrfs_extent_data_ref_count(leaf, ref1); | |
1197 | } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) { | |
1198 | ref2 = btrfs_item_ptr(leaf, path->slots[0], | |
1199 | struct btrfs_shared_data_ref); | |
1200 | num_refs = btrfs_shared_data_ref_count(leaf, ref2); | |
1201 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
1202 | } else if (key.type == BTRFS_EXTENT_REF_V0_KEY) { | |
1203 | struct btrfs_extent_ref_v0 *ref0; | |
1204 | ref0 = btrfs_item_ptr(leaf, path->slots[0], | |
1205 | struct btrfs_extent_ref_v0); | |
1206 | num_refs = btrfs_ref_count_v0(leaf, ref0); | |
1207 | #endif | |
1208 | } else { | |
1209 | WARN_ON(1); | |
1210 | } | |
1211 | return num_refs; | |
1212 | } | |
1213 | ||
1214 | static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans, | |
1215 | struct btrfs_root *root, | |
1216 | struct btrfs_path *path, | |
1217 | u64 bytenr, u64 parent, | |
1218 | u64 root_objectid) | |
1219 | { | |
1220 | struct btrfs_key key; | |
1221 | int ret; | |
1222 | ||
1223 | key.objectid = bytenr; | |
1224 | if (parent) { | |
1225 | key.type = BTRFS_SHARED_BLOCK_REF_KEY; | |
1226 | key.offset = parent; | |
1227 | } else { | |
1228 | key.type = BTRFS_TREE_BLOCK_REF_KEY; | |
1229 | key.offset = root_objectid; | |
1230 | } | |
1231 | ||
1232 | ret = btrfs_search_slot(trans, root, &key, path, -1, 1); | |
1233 | if (ret > 0) | |
1234 | ret = -ENOENT; | |
1235 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
1236 | if (ret == -ENOENT && parent) { | |
1237 | btrfs_release_path(root, path); | |
1238 | key.type = BTRFS_EXTENT_REF_V0_KEY; | |
1239 | ret = btrfs_search_slot(trans, root, &key, path, -1, 1); | |
1240 | if (ret > 0) | |
1241 | ret = -ENOENT; | |
1242 | } | |
1243 | #endif | |
1244 | return ret; | |
1245 | } | |
1246 | ||
1247 | static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans, | |
1248 | struct btrfs_root *root, | |
1249 | struct btrfs_path *path, | |
1250 | u64 bytenr, u64 parent, | |
1251 | u64 root_objectid) | |
1252 | { | |
1253 | struct btrfs_key key; | |
1254 | int ret; | |
1255 | ||
1256 | key.objectid = bytenr; | |
1257 | if (parent) { | |
1258 | key.type = BTRFS_SHARED_BLOCK_REF_KEY; | |
1259 | key.offset = parent; | |
1260 | } else { | |
1261 | key.type = BTRFS_TREE_BLOCK_REF_KEY; | |
1262 | key.offset = root_objectid; | |
1263 | } | |
1264 | ||
1265 | ret = btrfs_insert_empty_item(trans, root, path, &key, 0); | |
1266 | btrfs_release_path(root, path); | |
1267 | return ret; | |
1268 | } | |
1269 | ||
1270 | static inline int extent_ref_type(u64 parent, u64 owner) | |
1271 | { | |
1272 | int type; | |
1273 | if (owner < BTRFS_FIRST_FREE_OBJECTID) { | |
1274 | if (parent > 0) | |
1275 | type = BTRFS_SHARED_BLOCK_REF_KEY; | |
1276 | else | |
1277 | type = BTRFS_TREE_BLOCK_REF_KEY; | |
1278 | } else { | |
1279 | if (parent > 0) | |
1280 | type = BTRFS_SHARED_DATA_REF_KEY; | |
1281 | else | |
1282 | type = BTRFS_EXTENT_DATA_REF_KEY; | |
1283 | } | |
1284 | return type; | |
1285 | } | |
1286 | ||
1287 | static int find_next_key(struct btrfs_path *path, int level, | |
1288 | struct btrfs_key *key) | |
1289 | ||
1290 | { | |
1291 | for (; level < BTRFS_MAX_LEVEL; level++) { | |
1292 | if (!path->nodes[level]) | |
1293 | break; | |
1294 | if (path->slots[level] + 1 >= | |
1295 | btrfs_header_nritems(path->nodes[level])) | |
1296 | continue; | |
1297 | if (level == 0) | |
1298 | btrfs_item_key_to_cpu(path->nodes[level], key, | |
1299 | path->slots[level] + 1); | |
1300 | else | |
1301 | btrfs_node_key_to_cpu(path->nodes[level], key, | |
1302 | path->slots[level] + 1); | |
1303 | return 0; | |
1304 | } | |
1305 | return 1; | |
1306 | } | |
1307 | ||
1308 | /* | |
1309 | * look for inline back ref. if back ref is found, *ref_ret is set | |
1310 | * to the address of inline back ref, and 0 is returned. | |
1311 | * | |
1312 | * if back ref isn't found, *ref_ret is set to the address where it | |
1313 | * should be inserted, and -ENOENT is returned. | |
1314 | * | |
1315 | * if insert is true and there are too many inline back refs, the path | |
1316 | * points to the extent item, and -EAGAIN is returned. | |
1317 | * | |
1318 | * NOTE: inline back refs are ordered in the same way that back ref | |
1319 | * items in the tree are ordered. | |
1320 | */ | |
1321 | static noinline_for_stack | |
1322 | int lookup_inline_extent_backref(struct btrfs_trans_handle *trans, | |
1323 | struct btrfs_root *root, | |
1324 | struct btrfs_path *path, | |
1325 | struct btrfs_extent_inline_ref **ref_ret, | |
1326 | u64 bytenr, u64 num_bytes, | |
1327 | u64 parent, u64 root_objectid, | |
1328 | u64 owner, u64 offset, int insert) | |
1329 | { | |
1330 | struct btrfs_key key; | |
1331 | struct extent_buffer *leaf; | |
1332 | struct btrfs_extent_item *ei; | |
1333 | struct btrfs_extent_inline_ref *iref; | |
1334 | u64 flags; | |
1335 | u64 item_size; | |
1336 | unsigned long ptr; | |
1337 | unsigned long end; | |
1338 | int extra_size; | |
1339 | int type; | |
1340 | int want; | |
1341 | int ret; | |
1342 | int err = 0; | |
1343 | ||
1344 | key.objectid = bytenr; | |
1345 | key.type = BTRFS_EXTENT_ITEM_KEY; | |
1346 | key.offset = num_bytes; | |
1347 | ||
1348 | want = extent_ref_type(parent, owner); | |
1349 | if (insert) { | |
1350 | extra_size = btrfs_extent_inline_ref_size(want); | |
1351 | path->keep_locks = 1; | |
1352 | } else | |
1353 | extra_size = -1; | |
1354 | ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1); | |
1355 | if (ret < 0) { | |
1356 | err = ret; | |
1357 | goto out; | |
1358 | } | |
1359 | BUG_ON(ret); | |
1360 | ||
1361 | leaf = path->nodes[0]; | |
1362 | item_size = btrfs_item_size_nr(leaf, path->slots[0]); | |
1363 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
1364 | if (item_size < sizeof(*ei)) { | |
1365 | if (!insert) { | |
1366 | err = -ENOENT; | |
1367 | goto out; | |
1368 | } | |
1369 | ret = convert_extent_item_v0(trans, root, path, owner, | |
1370 | extra_size); | |
1371 | if (ret < 0) { | |
1372 | err = ret; | |
1373 | goto out; | |
1374 | } | |
1375 | leaf = path->nodes[0]; | |
1376 | item_size = btrfs_item_size_nr(leaf, path->slots[0]); | |
1377 | } | |
1378 | #endif | |
1379 | BUG_ON(item_size < sizeof(*ei)); | |
1380 | ||
1381 | ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item); | |
1382 | flags = btrfs_extent_flags(leaf, ei); | |
1383 | ||
1384 | ptr = (unsigned long)(ei + 1); | |
1385 | end = (unsigned long)ei + item_size; | |
1386 | ||
1387 | if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { | |
1388 | ptr += sizeof(struct btrfs_tree_block_info); | |
1389 | BUG_ON(ptr > end); | |
1390 | } else { | |
1391 | BUG_ON(!(flags & BTRFS_EXTENT_FLAG_DATA)); | |
1392 | } | |
1393 | ||
1394 | err = -ENOENT; | |
1395 | while (1) { | |
1396 | if (ptr >= end) { | |
1397 | WARN_ON(ptr > end); | |
1398 | break; | |
1399 | } | |
1400 | iref = (struct btrfs_extent_inline_ref *)ptr; | |
1401 | type = btrfs_extent_inline_ref_type(leaf, iref); | |
1402 | if (want < type) | |
1403 | break; | |
1404 | if (want > type) { | |
1405 | ptr += btrfs_extent_inline_ref_size(type); | |
1406 | continue; | |
1407 | } | |
1408 | ||
1409 | if (type == BTRFS_EXTENT_DATA_REF_KEY) { | |
1410 | struct btrfs_extent_data_ref *dref; | |
1411 | dref = (struct btrfs_extent_data_ref *)(&iref->offset); | |
1412 | if (match_extent_data_ref(leaf, dref, root_objectid, | |
1413 | owner, offset)) { | |
1414 | err = 0; | |
1415 | break; | |
1416 | } | |
1417 | if (hash_extent_data_ref_item(leaf, dref) < | |
1418 | hash_extent_data_ref(root_objectid, owner, offset)) | |
1419 | break; | |
1420 | } else { | |
1421 | u64 ref_offset; | |
1422 | ref_offset = btrfs_extent_inline_ref_offset(leaf, iref); | |
1423 | if (parent > 0) { | |
1424 | if (parent == ref_offset) { | |
1425 | err = 0; | |
1426 | break; | |
1427 | } | |
1428 | if (ref_offset < parent) | |
1429 | break; | |
1430 | } else { | |
1431 | if (root_objectid == ref_offset) { | |
1432 | err = 0; | |
1433 | break; | |
1434 | } | |
1435 | if (ref_offset < root_objectid) | |
1436 | break; | |
1437 | } | |
1438 | } | |
1439 | ptr += btrfs_extent_inline_ref_size(type); | |
1440 | } | |
1441 | if (err == -ENOENT && insert) { | |
1442 | if (item_size + extra_size >= | |
1443 | BTRFS_MAX_EXTENT_ITEM_SIZE(root)) { | |
1444 | err = -EAGAIN; | |
1445 | goto out; | |
1446 | } | |
1447 | /* | |
1448 | * To add new inline back ref, we have to make sure | |
1449 | * there is no corresponding back ref item. | |
1450 | * For simplicity, we just do not add new inline back | |
1451 | * ref if there is any kind of item for this block | |
1452 | */ | |
1453 | if (find_next_key(path, 0, &key) == 0 && | |
1454 | key.objectid == bytenr && | |
1455 | key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) { | |
1456 | err = -EAGAIN; | |
1457 | goto out; | |
1458 | } | |
1459 | } | |
1460 | *ref_ret = (struct btrfs_extent_inline_ref *)ptr; | |
1461 | out: | |
1462 | if (insert) { | |
1463 | path->keep_locks = 0; | |
1464 | btrfs_unlock_up_safe(path, 1); | |
1465 | } | |
1466 | return err; | |
1467 | } | |
1468 | ||
1469 | /* | |
1470 | * helper to add new inline back ref | |
1471 | */ | |
1472 | static noinline_for_stack | |
1473 | int setup_inline_extent_backref(struct btrfs_trans_handle *trans, | |
1474 | struct btrfs_root *root, | |
1475 | struct btrfs_path *path, | |
1476 | struct btrfs_extent_inline_ref *iref, | |
1477 | u64 parent, u64 root_objectid, | |
1478 | u64 owner, u64 offset, int refs_to_add, | |
1479 | struct btrfs_delayed_extent_op *extent_op) | |
1480 | { | |
1481 | struct extent_buffer *leaf; | |
1482 | struct btrfs_extent_item *ei; | |
1483 | unsigned long ptr; | |
1484 | unsigned long end; | |
1485 | unsigned long item_offset; | |
1486 | u64 refs; | |
1487 | int size; | |
1488 | int type; | |
1489 | int ret; | |
1490 | ||
1491 | leaf = path->nodes[0]; | |
1492 | ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item); | |
1493 | item_offset = (unsigned long)iref - (unsigned long)ei; | |
1494 | ||
1495 | type = extent_ref_type(parent, owner); | |
1496 | size = btrfs_extent_inline_ref_size(type); | |
1497 | ||
1498 | ret = btrfs_extend_item(trans, root, path, size); | |
1499 | BUG_ON(ret); | |
1500 | ||
1501 | ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item); | |
1502 | refs = btrfs_extent_refs(leaf, ei); | |
1503 | refs += refs_to_add; | |
1504 | btrfs_set_extent_refs(leaf, ei, refs); | |
1505 | if (extent_op) | |
1506 | __run_delayed_extent_op(extent_op, leaf, ei); | |
1507 | ||
1508 | ptr = (unsigned long)ei + item_offset; | |
1509 | end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]); | |
1510 | if (ptr < end - size) | |
1511 | memmove_extent_buffer(leaf, ptr + size, ptr, | |
1512 | end - size - ptr); | |
1513 | ||
1514 | iref = (struct btrfs_extent_inline_ref *)ptr; | |
1515 | btrfs_set_extent_inline_ref_type(leaf, iref, type); | |
1516 | if (type == BTRFS_EXTENT_DATA_REF_KEY) { | |
1517 | struct btrfs_extent_data_ref *dref; | |
1518 | dref = (struct btrfs_extent_data_ref *)(&iref->offset); | |
1519 | btrfs_set_extent_data_ref_root(leaf, dref, root_objectid); | |
1520 | btrfs_set_extent_data_ref_objectid(leaf, dref, owner); | |
1521 | btrfs_set_extent_data_ref_offset(leaf, dref, offset); | |
1522 | btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add); | |
1523 | } else if (type == BTRFS_SHARED_DATA_REF_KEY) { | |
1524 | struct btrfs_shared_data_ref *sref; | |
1525 | sref = (struct btrfs_shared_data_ref *)(iref + 1); | |
1526 | btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add); | |
1527 | btrfs_set_extent_inline_ref_offset(leaf, iref, parent); | |
1528 | } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) { | |
1529 | btrfs_set_extent_inline_ref_offset(leaf, iref, parent); | |
1530 | } else { | |
1531 | btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid); | |
1532 | } | |
1533 | btrfs_mark_buffer_dirty(leaf); | |
1534 | return 0; | |
1535 | } | |
1536 | ||
1537 | static int lookup_extent_backref(struct btrfs_trans_handle *trans, | |
1538 | struct btrfs_root *root, | |
1539 | struct btrfs_path *path, | |
1540 | struct btrfs_extent_inline_ref **ref_ret, | |
1541 | u64 bytenr, u64 num_bytes, u64 parent, | |
1542 | u64 root_objectid, u64 owner, u64 offset) | |
1543 | { | |
1544 | int ret; | |
1545 | ||
1546 | ret = lookup_inline_extent_backref(trans, root, path, ref_ret, | |
1547 | bytenr, num_bytes, parent, | |
1548 | root_objectid, owner, offset, 0); | |
1549 | if (ret != -ENOENT) | |
1550 | return ret; | |
1551 | ||
1552 | btrfs_release_path(root, path); | |
1553 | *ref_ret = NULL; | |
1554 | ||
1555 | if (owner < BTRFS_FIRST_FREE_OBJECTID) { | |
1556 | ret = lookup_tree_block_ref(trans, root, path, bytenr, parent, | |
1557 | root_objectid); | |
1558 | } else { | |
1559 | ret = lookup_extent_data_ref(trans, root, path, bytenr, parent, | |
1560 | root_objectid, owner, offset); | |
1561 | } | |
1562 | return ret; | |
1563 | } | |
1564 | ||
1565 | /* | |
1566 | * helper to update/remove inline back ref | |
1567 | */ | |
1568 | static noinline_for_stack | |
1569 | int update_inline_extent_backref(struct btrfs_trans_handle *trans, | |
1570 | struct btrfs_root *root, | |
1571 | struct btrfs_path *path, | |
1572 | struct btrfs_extent_inline_ref *iref, | |
1573 | int refs_to_mod, | |
1574 | struct btrfs_delayed_extent_op *extent_op) | |
1575 | { | |
1576 | struct extent_buffer *leaf; | |
1577 | struct btrfs_extent_item *ei; | |
1578 | struct btrfs_extent_data_ref *dref = NULL; | |
1579 | struct btrfs_shared_data_ref *sref = NULL; | |
1580 | unsigned long ptr; | |
1581 | unsigned long end; | |
1582 | u32 item_size; | |
1583 | int size; | |
1584 | int type; | |
1585 | int ret; | |
1586 | u64 refs; | |
1587 | ||
1588 | leaf = path->nodes[0]; | |
1589 | ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item); | |
1590 | refs = btrfs_extent_refs(leaf, ei); | |
1591 | WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0); | |
1592 | refs += refs_to_mod; | |
1593 | btrfs_set_extent_refs(leaf, ei, refs); | |
1594 | if (extent_op) | |
1595 | __run_delayed_extent_op(extent_op, leaf, ei); | |
1596 | ||
1597 | type = btrfs_extent_inline_ref_type(leaf, iref); | |
1598 | ||
1599 | if (type == BTRFS_EXTENT_DATA_REF_KEY) { | |
1600 | dref = (struct btrfs_extent_data_ref *)(&iref->offset); | |
1601 | refs = btrfs_extent_data_ref_count(leaf, dref); | |
1602 | } else if (type == BTRFS_SHARED_DATA_REF_KEY) { | |
1603 | sref = (struct btrfs_shared_data_ref *)(iref + 1); | |
1604 | refs = btrfs_shared_data_ref_count(leaf, sref); | |
1605 | } else { | |
1606 | refs = 1; | |
1607 | BUG_ON(refs_to_mod != -1); | |
1608 | } | |
1609 | ||
1610 | BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod); | |
1611 | refs += refs_to_mod; | |
1612 | ||
1613 | if (refs > 0) { | |
1614 | if (type == BTRFS_EXTENT_DATA_REF_KEY) | |
1615 | btrfs_set_extent_data_ref_count(leaf, dref, refs); | |
1616 | else | |
1617 | btrfs_set_shared_data_ref_count(leaf, sref, refs); | |
1618 | } else { | |
1619 | size = btrfs_extent_inline_ref_size(type); | |
1620 | item_size = btrfs_item_size_nr(leaf, path->slots[0]); | |
1621 | ptr = (unsigned long)iref; | |
1622 | end = (unsigned long)ei + item_size; | |
1623 | if (ptr + size < end) | |
1624 | memmove_extent_buffer(leaf, ptr, ptr + size, | |
1625 | end - ptr - size); | |
1626 | item_size -= size; | |
1627 | ret = btrfs_truncate_item(trans, root, path, item_size, 1); | |
1628 | BUG_ON(ret); | |
1629 | } | |
1630 | btrfs_mark_buffer_dirty(leaf); | |
1631 | return 0; | |
1632 | } | |
1633 | ||
1634 | static noinline_for_stack | |
1635 | int insert_inline_extent_backref(struct btrfs_trans_handle *trans, | |
1636 | struct btrfs_root *root, | |
1637 | struct btrfs_path *path, | |
1638 | u64 bytenr, u64 num_bytes, u64 parent, | |
1639 | u64 root_objectid, u64 owner, | |
1640 | u64 offset, int refs_to_add, | |
1641 | struct btrfs_delayed_extent_op *extent_op) | |
1642 | { | |
1643 | struct btrfs_extent_inline_ref *iref; | |
1644 | int ret; | |
1645 | ||
1646 | ret = lookup_inline_extent_backref(trans, root, path, &iref, | |
1647 | bytenr, num_bytes, parent, | |
1648 | root_objectid, owner, offset, 1); | |
1649 | if (ret == 0) { | |
1650 | BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID); | |
1651 | ret = update_inline_extent_backref(trans, root, path, iref, | |
1652 | refs_to_add, extent_op); | |
1653 | } else if (ret == -ENOENT) { | |
1654 | ret = setup_inline_extent_backref(trans, root, path, iref, | |
1655 | parent, root_objectid, | |
1656 | owner, offset, refs_to_add, | |
1657 | extent_op); | |
1658 | } | |
1659 | return ret; | |
1660 | } | |
1661 | ||
1662 | static int insert_extent_backref(struct btrfs_trans_handle *trans, | |
1663 | struct btrfs_root *root, | |
1664 | struct btrfs_path *path, | |
1665 | u64 bytenr, u64 parent, u64 root_objectid, | |
1666 | u64 owner, u64 offset, int refs_to_add) | |
1667 | { | |
1668 | int ret; | |
1669 | if (owner < BTRFS_FIRST_FREE_OBJECTID) { | |
1670 | BUG_ON(refs_to_add != 1); | |
1671 | ret = insert_tree_block_ref(trans, root, path, bytenr, | |
1672 | parent, root_objectid); | |
1673 | } else { | |
1674 | ret = insert_extent_data_ref(trans, root, path, bytenr, | |
1675 | parent, root_objectid, | |
1676 | owner, offset, refs_to_add); | |
1677 | } | |
1678 | return ret; | |
1679 | } | |
1680 | ||
1681 | static int remove_extent_backref(struct btrfs_trans_handle *trans, | |
1682 | struct btrfs_root *root, | |
1683 | struct btrfs_path *path, | |
1684 | struct btrfs_extent_inline_ref *iref, | |
1685 | int refs_to_drop, int is_data) | |
1686 | { | |
1687 | int ret; | |
1688 | ||
1689 | BUG_ON(!is_data && refs_to_drop != 1); | |
1690 | if (iref) { | |
1691 | ret = update_inline_extent_backref(trans, root, path, iref, | |
1692 | -refs_to_drop, NULL); | |
1693 | } else if (is_data) { | |
1694 | ret = remove_extent_data_ref(trans, root, path, refs_to_drop); | |
1695 | } else { | |
1696 | ret = btrfs_del_item(trans, root, path); | |
1697 | } | |
1698 | return ret; | |
1699 | } | |
1700 | ||
1701 | static void btrfs_issue_discard(struct block_device *bdev, | |
1702 | u64 start, u64 len) | |
1703 | { | |
1704 | blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_KERNEL, | |
1705 | DISCARD_FL_BARRIER); | |
1706 | } | |
1707 | ||
1708 | static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr, | |
1709 | u64 num_bytes) | |
1710 | { | |
1711 | int ret; | |
1712 | u64 map_length = num_bytes; | |
1713 | struct btrfs_multi_bio *multi = NULL; | |
1714 | ||
1715 | if (!btrfs_test_opt(root, DISCARD)) | |
1716 | return 0; | |
1717 | ||
1718 | /* Tell the block device(s) that the sectors can be discarded */ | |
1719 | ret = btrfs_map_block(&root->fs_info->mapping_tree, READ, | |
1720 | bytenr, &map_length, &multi, 0); | |
1721 | if (!ret) { | |
1722 | struct btrfs_bio_stripe *stripe = multi->stripes; | |
1723 | int i; | |
1724 | ||
1725 | if (map_length > num_bytes) | |
1726 | map_length = num_bytes; | |
1727 | ||
1728 | for (i = 0; i < multi->num_stripes; i++, stripe++) { | |
1729 | btrfs_issue_discard(stripe->dev->bdev, | |
1730 | stripe->physical, | |
1731 | map_length); | |
1732 | } | |
1733 | kfree(multi); | |
1734 | } | |
1735 | ||
1736 | return ret; | |
1737 | } | |
1738 | ||
1739 | int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans, | |
1740 | struct btrfs_root *root, | |
1741 | u64 bytenr, u64 num_bytes, u64 parent, | |
1742 | u64 root_objectid, u64 owner, u64 offset) | |
1743 | { | |
1744 | int ret; | |
1745 | BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID && | |
1746 | root_objectid == BTRFS_TREE_LOG_OBJECTID); | |
1747 | ||
1748 | if (owner < BTRFS_FIRST_FREE_OBJECTID) { | |
1749 | ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes, | |
1750 | parent, root_objectid, (int)owner, | |
1751 | BTRFS_ADD_DELAYED_REF, NULL); | |
1752 | } else { | |
1753 | ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes, | |
1754 | parent, root_objectid, owner, offset, | |
1755 | BTRFS_ADD_DELAYED_REF, NULL); | |
1756 | } | |
1757 | return ret; | |
1758 | } | |
1759 | ||
1760 | static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans, | |
1761 | struct btrfs_root *root, | |
1762 | u64 bytenr, u64 num_bytes, | |
1763 | u64 parent, u64 root_objectid, | |
1764 | u64 owner, u64 offset, int refs_to_add, | |
1765 | struct btrfs_delayed_extent_op *extent_op) | |
1766 | { | |
1767 | struct btrfs_path *path; | |
1768 | struct extent_buffer *leaf; | |
1769 | struct btrfs_extent_item *item; | |
1770 | u64 refs; | |
1771 | int ret; | |
1772 | int err = 0; | |
1773 | ||
1774 | path = btrfs_alloc_path(); | |
1775 | if (!path) | |
1776 | return -ENOMEM; | |
1777 | ||
1778 | path->reada = 1; | |
1779 | path->leave_spinning = 1; | |
1780 | /* this will setup the path even if it fails to insert the back ref */ | |
1781 | ret = insert_inline_extent_backref(trans, root->fs_info->extent_root, | |
1782 | path, bytenr, num_bytes, parent, | |
1783 | root_objectid, owner, offset, | |
1784 | refs_to_add, extent_op); | |
1785 | if (ret == 0) | |
1786 | goto out; | |
1787 | ||
1788 | if (ret != -EAGAIN) { | |
1789 | err = ret; | |
1790 | goto out; | |
1791 | } | |
1792 | ||
1793 | leaf = path->nodes[0]; | |
1794 | item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item); | |
1795 | refs = btrfs_extent_refs(leaf, item); | |
1796 | btrfs_set_extent_refs(leaf, item, refs + refs_to_add); | |
1797 | if (extent_op) | |
1798 | __run_delayed_extent_op(extent_op, leaf, item); | |
1799 | ||
1800 | btrfs_mark_buffer_dirty(leaf); | |
1801 | btrfs_release_path(root->fs_info->extent_root, path); | |
1802 | ||
1803 | path->reada = 1; | |
1804 | path->leave_spinning = 1; | |
1805 | ||
1806 | /* now insert the actual backref */ | |
1807 | ret = insert_extent_backref(trans, root->fs_info->extent_root, | |
1808 | path, bytenr, parent, root_objectid, | |
1809 | owner, offset, refs_to_add); | |
1810 | BUG_ON(ret); | |
1811 | out: | |
1812 | btrfs_free_path(path); | |
1813 | return err; | |
1814 | } | |
1815 | ||
1816 | static int run_delayed_data_ref(struct btrfs_trans_handle *trans, | |
1817 | struct btrfs_root *root, | |
1818 | struct btrfs_delayed_ref_node *node, | |
1819 | struct btrfs_delayed_extent_op *extent_op, | |
1820 | int insert_reserved) | |
1821 | { | |
1822 | int ret = 0; | |
1823 | struct btrfs_delayed_data_ref *ref; | |
1824 | struct btrfs_key ins; | |
1825 | u64 parent = 0; | |
1826 | u64 ref_root = 0; | |
1827 | u64 flags = 0; | |
1828 | ||
1829 | ins.objectid = node->bytenr; | |
1830 | ins.offset = node->num_bytes; | |
1831 | ins.type = BTRFS_EXTENT_ITEM_KEY; | |
1832 | ||
1833 | ref = btrfs_delayed_node_to_data_ref(node); | |
1834 | if (node->type == BTRFS_SHARED_DATA_REF_KEY) | |
1835 | parent = ref->parent; | |
1836 | else | |
1837 | ref_root = ref->root; | |
1838 | ||
1839 | if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) { | |
1840 | if (extent_op) { | |
1841 | BUG_ON(extent_op->update_key); | |
1842 | flags |= extent_op->flags_to_set; | |
1843 | } | |
1844 | ret = alloc_reserved_file_extent(trans, root, | |
1845 | parent, ref_root, flags, | |
1846 | ref->objectid, ref->offset, | |
1847 | &ins, node->ref_mod); | |
1848 | } else if (node->action == BTRFS_ADD_DELAYED_REF) { | |
1849 | ret = __btrfs_inc_extent_ref(trans, root, node->bytenr, | |
1850 | node->num_bytes, parent, | |
1851 | ref_root, ref->objectid, | |
1852 | ref->offset, node->ref_mod, | |
1853 | extent_op); | |
1854 | } else if (node->action == BTRFS_DROP_DELAYED_REF) { | |
1855 | ret = __btrfs_free_extent(trans, root, node->bytenr, | |
1856 | node->num_bytes, parent, | |
1857 | ref_root, ref->objectid, | |
1858 | ref->offset, node->ref_mod, | |
1859 | extent_op); | |
1860 | } else { | |
1861 | BUG(); | |
1862 | } | |
1863 | return ret; | |
1864 | } | |
1865 | ||
1866 | static void __run_delayed_extent_op(struct btrfs_delayed_extent_op *extent_op, | |
1867 | struct extent_buffer *leaf, | |
1868 | struct btrfs_extent_item *ei) | |
1869 | { | |
1870 | u64 flags = btrfs_extent_flags(leaf, ei); | |
1871 | if (extent_op->update_flags) { | |
1872 | flags |= extent_op->flags_to_set; | |
1873 | btrfs_set_extent_flags(leaf, ei, flags); | |
1874 | } | |
1875 | ||
1876 | if (extent_op->update_key) { | |
1877 | struct btrfs_tree_block_info *bi; | |
1878 | BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)); | |
1879 | bi = (struct btrfs_tree_block_info *)(ei + 1); | |
1880 | btrfs_set_tree_block_key(leaf, bi, &extent_op->key); | |
1881 | } | |
1882 | } | |
1883 | ||
1884 | static int run_delayed_extent_op(struct btrfs_trans_handle *trans, | |
1885 | struct btrfs_root *root, | |
1886 | struct btrfs_delayed_ref_node *node, | |
1887 | struct btrfs_delayed_extent_op *extent_op) | |
1888 | { | |
1889 | struct btrfs_key key; | |
1890 | struct btrfs_path *path; | |
1891 | struct btrfs_extent_item *ei; | |
1892 | struct extent_buffer *leaf; | |
1893 | u32 item_size; | |
1894 | int ret; | |
1895 | int err = 0; | |
1896 | ||
1897 | path = btrfs_alloc_path(); | |
1898 | if (!path) | |
1899 | return -ENOMEM; | |
1900 | ||
1901 | key.objectid = node->bytenr; | |
1902 | key.type = BTRFS_EXTENT_ITEM_KEY; | |
1903 | key.offset = node->num_bytes; | |
1904 | ||
1905 | path->reada = 1; | |
1906 | path->leave_spinning = 1; | |
1907 | ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, | |
1908 | path, 0, 1); | |
1909 | if (ret < 0) { | |
1910 | err = ret; | |
1911 | goto out; | |
1912 | } | |
1913 | if (ret > 0) { | |
1914 | err = -EIO; | |
1915 | goto out; | |
1916 | } | |
1917 | ||
1918 | leaf = path->nodes[0]; | |
1919 | item_size = btrfs_item_size_nr(leaf, path->slots[0]); | |
1920 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
1921 | if (item_size < sizeof(*ei)) { | |
1922 | ret = convert_extent_item_v0(trans, root->fs_info->extent_root, | |
1923 | path, (u64)-1, 0); | |
1924 | if (ret < 0) { | |
1925 | err = ret; | |
1926 | goto out; | |
1927 | } | |
1928 | leaf = path->nodes[0]; | |
1929 | item_size = btrfs_item_size_nr(leaf, path->slots[0]); | |
1930 | } | |
1931 | #endif | |
1932 | BUG_ON(item_size < sizeof(*ei)); | |
1933 | ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item); | |
1934 | __run_delayed_extent_op(extent_op, leaf, ei); | |
1935 | ||
1936 | btrfs_mark_buffer_dirty(leaf); | |
1937 | out: | |
1938 | btrfs_free_path(path); | |
1939 | return err; | |
1940 | } | |
1941 | ||
1942 | static int run_delayed_tree_ref(struct btrfs_trans_handle *trans, | |
1943 | struct btrfs_root *root, | |
1944 | struct btrfs_delayed_ref_node *node, | |
1945 | struct btrfs_delayed_extent_op *extent_op, | |
1946 | int insert_reserved) | |
1947 | { | |
1948 | int ret = 0; | |
1949 | struct btrfs_delayed_tree_ref *ref; | |
1950 | struct btrfs_key ins; | |
1951 | u64 parent = 0; | |
1952 | u64 ref_root = 0; | |
1953 | ||
1954 | ins.objectid = node->bytenr; | |
1955 | ins.offset = node->num_bytes; | |
1956 | ins.type = BTRFS_EXTENT_ITEM_KEY; | |
1957 | ||
1958 | ref = btrfs_delayed_node_to_tree_ref(node); | |
1959 | if (node->type == BTRFS_SHARED_BLOCK_REF_KEY) | |
1960 | parent = ref->parent; | |
1961 | else | |
1962 | ref_root = ref->root; | |
1963 | ||
1964 | BUG_ON(node->ref_mod != 1); | |
1965 | if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) { | |
1966 | BUG_ON(!extent_op || !extent_op->update_flags || | |
1967 | !extent_op->update_key); | |
1968 | ret = alloc_reserved_tree_block(trans, root, | |
1969 | parent, ref_root, | |
1970 | extent_op->flags_to_set, | |
1971 | &extent_op->key, | |
1972 | ref->level, &ins); | |
1973 | } else if (node->action == BTRFS_ADD_DELAYED_REF) { | |
1974 | ret = __btrfs_inc_extent_ref(trans, root, node->bytenr, | |
1975 | node->num_bytes, parent, ref_root, | |
1976 | ref->level, 0, 1, extent_op); | |
1977 | } else if (node->action == BTRFS_DROP_DELAYED_REF) { | |
1978 | ret = __btrfs_free_extent(trans, root, node->bytenr, | |
1979 | node->num_bytes, parent, ref_root, | |
1980 | ref->level, 0, 1, extent_op); | |
1981 | } else { | |
1982 | BUG(); | |
1983 | } | |
1984 | return ret; | |
1985 | } | |
1986 | ||
1987 | /* helper function to actually process a single delayed ref entry */ | |
1988 | static int run_one_delayed_ref(struct btrfs_trans_handle *trans, | |
1989 | struct btrfs_root *root, | |
1990 | struct btrfs_delayed_ref_node *node, | |
1991 | struct btrfs_delayed_extent_op *extent_op, | |
1992 | int insert_reserved) | |
1993 | { | |
1994 | int ret; | |
1995 | if (btrfs_delayed_ref_is_head(node)) { | |
1996 | struct btrfs_delayed_ref_head *head; | |
1997 | /* | |
1998 | * we've hit the end of the chain and we were supposed | |
1999 | * to insert this extent into the tree. But, it got | |
2000 | * deleted before we ever needed to insert it, so all | |
2001 | * we have to do is clean up the accounting | |
2002 | */ | |
2003 | BUG_ON(extent_op); | |
2004 | head = btrfs_delayed_node_to_head(node); | |
2005 | if (insert_reserved) { | |
2006 | btrfs_pin_extent(root, node->bytenr, | |
2007 | node->num_bytes, 1); | |
2008 | if (head->is_data) { | |
2009 | ret = btrfs_del_csums(trans, root, | |
2010 | node->bytenr, | |
2011 | node->num_bytes); | |
2012 | BUG_ON(ret); | |
2013 | } | |
2014 | } | |
2015 | mutex_unlock(&head->mutex); | |
2016 | return 0; | |
2017 | } | |
2018 | ||
2019 | if (node->type == BTRFS_TREE_BLOCK_REF_KEY || | |
2020 | node->type == BTRFS_SHARED_BLOCK_REF_KEY) | |
2021 | ret = run_delayed_tree_ref(trans, root, node, extent_op, | |
2022 | insert_reserved); | |
2023 | else if (node->type == BTRFS_EXTENT_DATA_REF_KEY || | |
2024 | node->type == BTRFS_SHARED_DATA_REF_KEY) | |
2025 | ret = run_delayed_data_ref(trans, root, node, extent_op, | |
2026 | insert_reserved); | |
2027 | else | |
2028 | BUG(); | |
2029 | return ret; | |
2030 | } | |
2031 | ||
2032 | static noinline struct btrfs_delayed_ref_node * | |
2033 | select_delayed_ref(struct btrfs_delayed_ref_head *head) | |
2034 | { | |
2035 | struct rb_node *node; | |
2036 | struct btrfs_delayed_ref_node *ref; | |
2037 | int action = BTRFS_ADD_DELAYED_REF; | |
2038 | again: | |
2039 | /* | |
2040 | * select delayed ref of type BTRFS_ADD_DELAYED_REF first. | |
2041 | * this prevents ref count from going down to zero when | |
2042 | * there still are pending delayed ref. | |
2043 | */ | |
2044 | node = rb_prev(&head->node.rb_node); | |
2045 | while (1) { | |
2046 | if (!node) | |
2047 | break; | |
2048 | ref = rb_entry(node, struct btrfs_delayed_ref_node, | |
2049 | rb_node); | |
2050 | if (ref->bytenr != head->node.bytenr) | |
2051 | break; | |
2052 | if (ref->action == action) | |
2053 | return ref; | |
2054 | node = rb_prev(node); | |
2055 | } | |
2056 | if (action == BTRFS_ADD_DELAYED_REF) { | |
2057 | action = BTRFS_DROP_DELAYED_REF; | |
2058 | goto again; | |
2059 | } | |
2060 | return NULL; | |
2061 | } | |
2062 | ||
2063 | static noinline int run_clustered_refs(struct btrfs_trans_handle *trans, | |
2064 | struct btrfs_root *root, | |
2065 | struct list_head *cluster) | |
2066 | { | |
2067 | struct btrfs_delayed_ref_root *delayed_refs; | |
2068 | struct btrfs_delayed_ref_node *ref; | |
2069 | struct btrfs_delayed_ref_head *locked_ref = NULL; | |
2070 | struct btrfs_delayed_extent_op *extent_op; | |
2071 | int ret; | |
2072 | int count = 0; | |
2073 | int must_insert_reserved = 0; | |
2074 | ||
2075 | delayed_refs = &trans->transaction->delayed_refs; | |
2076 | while (1) { | |
2077 | if (!locked_ref) { | |
2078 | /* pick a new head ref from the cluster list */ | |
2079 | if (list_empty(cluster)) | |
2080 | break; | |
2081 | ||
2082 | locked_ref = list_entry(cluster->next, | |
2083 | struct btrfs_delayed_ref_head, cluster); | |
2084 | ||
2085 | /* grab the lock that says we are going to process | |
2086 | * all the refs for this head */ | |
2087 | ret = btrfs_delayed_ref_lock(trans, locked_ref); | |
2088 | ||
2089 | /* | |
2090 | * we may have dropped the spin lock to get the head | |
2091 | * mutex lock, and that might have given someone else | |
2092 | * time to free the head. If that's true, it has been | |
2093 | * removed from our list and we can move on. | |
2094 | */ | |
2095 | if (ret == -EAGAIN) { | |
2096 | locked_ref = NULL; | |
2097 | count++; | |
2098 | continue; | |
2099 | } | |
2100 | } | |
2101 | ||
2102 | /* | |
2103 | * record the must insert reserved flag before we | |
2104 | * drop the spin lock. | |
2105 | */ | |
2106 | must_insert_reserved = locked_ref->must_insert_reserved; | |
2107 | locked_ref->must_insert_reserved = 0; | |
2108 | ||
2109 | extent_op = locked_ref->extent_op; | |
2110 | locked_ref->extent_op = NULL; | |
2111 | ||
2112 | /* | |
2113 | * locked_ref is the head node, so we have to go one | |
2114 | * node back for any delayed ref updates | |
2115 | */ | |
2116 | ref = select_delayed_ref(locked_ref); | |
2117 | if (!ref) { | |
2118 | /* All delayed refs have been processed, Go ahead | |
2119 | * and send the head node to run_one_delayed_ref, | |
2120 | * so that any accounting fixes can happen | |
2121 | */ | |
2122 | ref = &locked_ref->node; | |
2123 | ||
2124 | if (extent_op && must_insert_reserved) { | |
2125 | kfree(extent_op); | |
2126 | extent_op = NULL; | |
2127 | } | |
2128 | ||
2129 | if (extent_op) { | |
2130 | spin_unlock(&delayed_refs->lock); | |
2131 | ||
2132 | ret = run_delayed_extent_op(trans, root, | |
2133 | ref, extent_op); | |
2134 | BUG_ON(ret); | |
2135 | kfree(extent_op); | |
2136 | ||
2137 | cond_resched(); | |
2138 | spin_lock(&delayed_refs->lock); | |
2139 | continue; | |
2140 | } | |
2141 | ||
2142 | list_del_init(&locked_ref->cluster); | |
2143 | locked_ref = NULL; | |
2144 | } | |
2145 | ||
2146 | ref->in_tree = 0; | |
2147 | rb_erase(&ref->rb_node, &delayed_refs->root); | |
2148 | delayed_refs->num_entries--; | |
2149 | ||
2150 | spin_unlock(&delayed_refs->lock); | |
2151 | ||
2152 | ret = run_one_delayed_ref(trans, root, ref, extent_op, | |
2153 | must_insert_reserved); | |
2154 | BUG_ON(ret); | |
2155 | ||
2156 | btrfs_put_delayed_ref(ref); | |
2157 | kfree(extent_op); | |
2158 | count++; | |
2159 | ||
2160 | cond_resched(); | |
2161 | spin_lock(&delayed_refs->lock); | |
2162 | } | |
2163 | return count; | |
2164 | } | |
2165 | ||
2166 | /* | |
2167 | * this starts processing the delayed reference count updates and | |
2168 | * extent insertions we have queued up so far. count can be | |
2169 | * 0, which means to process everything in the tree at the start | |
2170 | * of the run (but not newly added entries), or it can be some target | |
2171 | * number you'd like to process. | |
2172 | */ | |
2173 | int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans, | |
2174 | struct btrfs_root *root, unsigned long count) | |
2175 | { | |
2176 | struct rb_node *node; | |
2177 | struct btrfs_delayed_ref_root *delayed_refs; | |
2178 | struct btrfs_delayed_ref_node *ref; | |
2179 | struct list_head cluster; | |
2180 | int ret; | |
2181 | int run_all = count == (unsigned long)-1; | |
2182 | int run_most = 0; | |
2183 | ||
2184 | if (root == root->fs_info->extent_root) | |
2185 | root = root->fs_info->tree_root; | |
2186 | ||
2187 | delayed_refs = &trans->transaction->delayed_refs; | |
2188 | INIT_LIST_HEAD(&cluster); | |
2189 | again: | |
2190 | spin_lock(&delayed_refs->lock); | |
2191 | if (count == 0) { | |
2192 | count = delayed_refs->num_entries * 2; | |
2193 | run_most = 1; | |
2194 | } | |
2195 | while (1) { | |
2196 | if (!(run_all || run_most) && | |
2197 | delayed_refs->num_heads_ready < 64) | |
2198 | break; | |
2199 | ||
2200 | /* | |
2201 | * go find something we can process in the rbtree. We start at | |
2202 | * the beginning of the tree, and then build a cluster | |
2203 | * of refs to process starting at the first one we are able to | |
2204 | * lock | |
2205 | */ | |
2206 | ret = btrfs_find_ref_cluster(trans, &cluster, | |
2207 | delayed_refs->run_delayed_start); | |
2208 | if (ret) | |
2209 | break; | |
2210 | ||
2211 | ret = run_clustered_refs(trans, root, &cluster); | |
2212 | BUG_ON(ret < 0); | |
2213 | ||
2214 | count -= min_t(unsigned long, ret, count); | |
2215 | ||
2216 | if (count == 0) | |
2217 | break; | |
2218 | } | |
2219 | ||
2220 | if (run_all) { | |
2221 | node = rb_first(&delayed_refs->root); | |
2222 | if (!node) | |
2223 | goto out; | |
2224 | count = (unsigned long)-1; | |
2225 | ||
2226 | while (node) { | |
2227 | ref = rb_entry(node, struct btrfs_delayed_ref_node, | |
2228 | rb_node); | |
2229 | if (btrfs_delayed_ref_is_head(ref)) { | |
2230 | struct btrfs_delayed_ref_head *head; | |
2231 | ||
2232 | head = btrfs_delayed_node_to_head(ref); | |
2233 | atomic_inc(&ref->refs); | |
2234 | ||
2235 | spin_unlock(&delayed_refs->lock); | |
2236 | mutex_lock(&head->mutex); | |
2237 | mutex_unlock(&head->mutex); | |
2238 | ||
2239 | btrfs_put_delayed_ref(ref); | |
2240 | cond_resched(); | |
2241 | goto again; | |
2242 | } | |
2243 | node = rb_next(node); | |
2244 | } | |
2245 | spin_unlock(&delayed_refs->lock); | |
2246 | schedule_timeout(1); | |
2247 | goto again; | |
2248 | } | |
2249 | out: | |
2250 | spin_unlock(&delayed_refs->lock); | |
2251 | return 0; | |
2252 | } | |
2253 | ||
2254 | int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans, | |
2255 | struct btrfs_root *root, | |
2256 | u64 bytenr, u64 num_bytes, u64 flags, | |
2257 | int is_data) | |
2258 | { | |
2259 | struct btrfs_delayed_extent_op *extent_op; | |
2260 | int ret; | |
2261 | ||
2262 | extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS); | |
2263 | if (!extent_op) | |
2264 | return -ENOMEM; | |
2265 | ||
2266 | extent_op->flags_to_set = flags; | |
2267 | extent_op->update_flags = 1; | |
2268 | extent_op->update_key = 0; | |
2269 | extent_op->is_data = is_data ? 1 : 0; | |
2270 | ||
2271 | ret = btrfs_add_delayed_extent_op(trans, bytenr, num_bytes, extent_op); | |
2272 | if (ret) | |
2273 | kfree(extent_op); | |
2274 | return ret; | |
2275 | } | |
2276 | ||
2277 | static noinline int check_delayed_ref(struct btrfs_trans_handle *trans, | |
2278 | struct btrfs_root *root, | |
2279 | struct btrfs_path *path, | |
2280 | u64 objectid, u64 offset, u64 bytenr) | |
2281 | { | |
2282 | struct btrfs_delayed_ref_head *head; | |
2283 | struct btrfs_delayed_ref_node *ref; | |
2284 | struct btrfs_delayed_data_ref *data_ref; | |
2285 | struct btrfs_delayed_ref_root *delayed_refs; | |
2286 | struct rb_node *node; | |
2287 | int ret = 0; | |
2288 | ||
2289 | ret = -ENOENT; | |
2290 | delayed_refs = &trans->transaction->delayed_refs; | |
2291 | spin_lock(&delayed_refs->lock); | |
2292 | head = btrfs_find_delayed_ref_head(trans, bytenr); | |
2293 | if (!head) | |
2294 | goto out; | |
2295 | ||
2296 | if (!mutex_trylock(&head->mutex)) { | |
2297 | atomic_inc(&head->node.refs); | |
2298 | spin_unlock(&delayed_refs->lock); | |
2299 | ||
2300 | btrfs_release_path(root->fs_info->extent_root, path); | |
2301 | ||
2302 | mutex_lock(&head->mutex); | |
2303 | mutex_unlock(&head->mutex); | |
2304 | btrfs_put_delayed_ref(&head->node); | |
2305 | return -EAGAIN; | |
2306 | } | |
2307 | ||
2308 | node = rb_prev(&head->node.rb_node); | |
2309 | if (!node) | |
2310 | goto out_unlock; | |
2311 | ||
2312 | ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node); | |
2313 | ||
2314 | if (ref->bytenr != bytenr) | |
2315 | goto out_unlock; | |
2316 | ||
2317 | ret = 1; | |
2318 | if (ref->type != BTRFS_EXTENT_DATA_REF_KEY) | |
2319 | goto out_unlock; | |
2320 | ||
2321 | data_ref = btrfs_delayed_node_to_data_ref(ref); | |
2322 | ||
2323 | node = rb_prev(node); | |
2324 | if (node) { | |
2325 | ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node); | |
2326 | if (ref->bytenr == bytenr) | |
2327 | goto out_unlock; | |
2328 | } | |
2329 | ||
2330 | if (data_ref->root != root->root_key.objectid || | |
2331 | data_ref->objectid != objectid || data_ref->offset != offset) | |
2332 | goto out_unlock; | |
2333 | ||
2334 | ret = 0; | |
2335 | out_unlock: | |
2336 | mutex_unlock(&head->mutex); | |
2337 | out: | |
2338 | spin_unlock(&delayed_refs->lock); | |
2339 | return ret; | |
2340 | } | |
2341 | ||
2342 | static noinline int check_committed_ref(struct btrfs_trans_handle *trans, | |
2343 | struct btrfs_root *root, | |
2344 | struct btrfs_path *path, | |
2345 | u64 objectid, u64 offset, u64 bytenr) | |
2346 | { | |
2347 | struct btrfs_root *extent_root = root->fs_info->extent_root; | |
2348 | struct extent_buffer *leaf; | |
2349 | struct btrfs_extent_data_ref *ref; | |
2350 | struct btrfs_extent_inline_ref *iref; | |
2351 | struct btrfs_extent_item *ei; | |
2352 | struct btrfs_key key; | |
2353 | u32 item_size; | |
2354 | int ret; | |
2355 | ||
2356 | key.objectid = bytenr; | |
2357 | key.offset = (u64)-1; | |
2358 | key.type = BTRFS_EXTENT_ITEM_KEY; | |
2359 | ||
2360 | ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0); | |
2361 | if (ret < 0) | |
2362 | goto out; | |
2363 | BUG_ON(ret == 0); | |
2364 | ||
2365 | ret = -ENOENT; | |
2366 | if (path->slots[0] == 0) | |
2367 | goto out; | |
2368 | ||
2369 | path->slots[0]--; | |
2370 | leaf = path->nodes[0]; | |
2371 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
2372 | ||
2373 | if (key.objectid != bytenr || key.type != BTRFS_EXTENT_ITEM_KEY) | |
2374 | goto out; | |
2375 | ||
2376 | ret = 1; | |
2377 | item_size = btrfs_item_size_nr(leaf, path->slots[0]); | |
2378 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
2379 | if (item_size < sizeof(*ei)) { | |
2380 | WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0)); | |
2381 | goto out; | |
2382 | } | |
2383 | #endif | |
2384 | ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item); | |
2385 | ||
2386 | if (item_size != sizeof(*ei) + | |
2387 | btrfs_extent_inline_ref_size(BTRFS_EXTENT_DATA_REF_KEY)) | |
2388 | goto out; | |
2389 | ||
2390 | if (btrfs_extent_generation(leaf, ei) <= | |
2391 | btrfs_root_last_snapshot(&root->root_item)) | |
2392 | goto out; | |
2393 | ||
2394 | iref = (struct btrfs_extent_inline_ref *)(ei + 1); | |
2395 | if (btrfs_extent_inline_ref_type(leaf, iref) != | |
2396 | BTRFS_EXTENT_DATA_REF_KEY) | |
2397 | goto out; | |
2398 | ||
2399 | ref = (struct btrfs_extent_data_ref *)(&iref->offset); | |
2400 | if (btrfs_extent_refs(leaf, ei) != | |
2401 | btrfs_extent_data_ref_count(leaf, ref) || | |
2402 | btrfs_extent_data_ref_root(leaf, ref) != | |
2403 | root->root_key.objectid || | |
2404 | btrfs_extent_data_ref_objectid(leaf, ref) != objectid || | |
2405 | btrfs_extent_data_ref_offset(leaf, ref) != offset) | |
2406 | goto out; | |
2407 | ||
2408 | ret = 0; | |
2409 | out: | |
2410 | return ret; | |
2411 | } | |
2412 | ||
2413 | int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans, | |
2414 | struct btrfs_root *root, | |
2415 | u64 objectid, u64 offset, u64 bytenr) | |
2416 | { | |
2417 | struct btrfs_path *path; | |
2418 | int ret; | |
2419 | int ret2; | |
2420 | ||
2421 | path = btrfs_alloc_path(); | |
2422 | if (!path) | |
2423 | return -ENOENT; | |
2424 | ||
2425 | do { | |
2426 | ret = check_committed_ref(trans, root, path, objectid, | |
2427 | offset, bytenr); | |
2428 | if (ret && ret != -ENOENT) | |
2429 | goto out; | |
2430 | ||
2431 | ret2 = check_delayed_ref(trans, root, path, objectid, | |
2432 | offset, bytenr); | |
2433 | } while (ret2 == -EAGAIN); | |
2434 | ||
2435 | if (ret2 && ret2 != -ENOENT) { | |
2436 | ret = ret2; | |
2437 | goto out; | |
2438 | } | |
2439 | ||
2440 | if (ret != -ENOENT || ret2 != -ENOENT) | |
2441 | ret = 0; | |
2442 | out: | |
2443 | btrfs_free_path(path); | |
2444 | if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID) | |
2445 | WARN_ON(ret > 0); | |
2446 | return ret; | |
2447 | } | |
2448 | ||
2449 | #if 0 | |
2450 | int btrfs_cache_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, | |
2451 | struct extent_buffer *buf, u32 nr_extents) | |
2452 | { | |
2453 | struct btrfs_key key; | |
2454 | struct btrfs_file_extent_item *fi; | |
2455 | u64 root_gen; | |
2456 | u32 nritems; | |
2457 | int i; | |
2458 | int level; | |
2459 | int ret = 0; | |
2460 | int shared = 0; | |
2461 | ||
2462 | if (!root->ref_cows) | |
2463 | return 0; | |
2464 | ||
2465 | if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) { | |
2466 | shared = 0; | |
2467 | root_gen = root->root_key.offset; | |
2468 | } else { | |
2469 | shared = 1; | |
2470 | root_gen = trans->transid - 1; | |
2471 | } | |
2472 | ||
2473 | level = btrfs_header_level(buf); | |
2474 | nritems = btrfs_header_nritems(buf); | |
2475 | ||
2476 | if (level == 0) { | |
2477 | struct btrfs_leaf_ref *ref; | |
2478 | struct btrfs_extent_info *info; | |
2479 | ||
2480 | ref = btrfs_alloc_leaf_ref(root, nr_extents); | |
2481 | if (!ref) { | |
2482 | ret = -ENOMEM; | |
2483 | goto out; | |
2484 | } | |
2485 | ||
2486 | ref->root_gen = root_gen; | |
2487 | ref->bytenr = buf->start; | |
2488 | ref->owner = btrfs_header_owner(buf); | |
2489 | ref->generation = btrfs_header_generation(buf); | |
2490 | ref->nritems = nr_extents; | |
2491 | info = ref->extents; | |
2492 | ||
2493 | for (i = 0; nr_extents > 0 && i < nritems; i++) { | |
2494 | u64 disk_bytenr; | |
2495 | btrfs_item_key_to_cpu(buf, &key, i); | |
2496 | if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) | |
2497 | continue; | |
2498 | fi = btrfs_item_ptr(buf, i, | |
2499 | struct btrfs_file_extent_item); | |
2500 | if (btrfs_file_extent_type(buf, fi) == | |
2501 | BTRFS_FILE_EXTENT_INLINE) | |
2502 | continue; | |
2503 | disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi); | |
2504 | if (disk_bytenr == 0) | |
2505 | continue; | |
2506 | ||
2507 | info->bytenr = disk_bytenr; | |
2508 | info->num_bytes = | |
2509 | btrfs_file_extent_disk_num_bytes(buf, fi); | |
2510 | info->objectid = key.objectid; | |
2511 | info->offset = key.offset; | |
2512 | info++; | |
2513 | } | |
2514 | ||
2515 | ret = btrfs_add_leaf_ref(root, ref, shared); | |
2516 | if (ret == -EEXIST && shared) { | |
2517 | struct btrfs_leaf_ref *old; | |
2518 | old = btrfs_lookup_leaf_ref(root, ref->bytenr); | |
2519 | BUG_ON(!old); | |
2520 | btrfs_remove_leaf_ref(root, old); | |
2521 | btrfs_free_leaf_ref(root, old); | |
2522 | ret = btrfs_add_leaf_ref(root, ref, shared); | |
2523 | } | |
2524 | WARN_ON(ret); | |
2525 | btrfs_free_leaf_ref(root, ref); | |
2526 | } | |
2527 | out: | |
2528 | return ret; | |
2529 | } | |
2530 | ||
2531 | /* when a block goes through cow, we update the reference counts of | |
2532 | * everything that block points to. The internal pointers of the block | |
2533 | * can be in just about any order, and it is likely to have clusters of | |
2534 | * things that are close together and clusters of things that are not. | |
2535 | * | |
2536 | * To help reduce the seeks that come with updating all of these reference | |
2537 | * counts, sort them by byte number before actual updates are done. | |
2538 | * | |
2539 | * struct refsort is used to match byte number to slot in the btree block. | |
2540 | * we sort based on the byte number and then use the slot to actually | |
2541 | * find the item. | |
2542 | * | |
2543 | * struct refsort is smaller than strcut btrfs_item and smaller than | |
2544 | * struct btrfs_key_ptr. Since we're currently limited to the page size | |
2545 | * for a btree block, there's no way for a kmalloc of refsorts for a | |
2546 | * single node to be bigger than a page. | |
2547 | */ | |
2548 | struct refsort { | |
2549 | u64 bytenr; | |
2550 | u32 slot; | |
2551 | }; | |
2552 | ||
2553 | /* | |
2554 | * for passing into sort() | |
2555 | */ | |
2556 | static int refsort_cmp(const void *a_void, const void *b_void) | |
2557 | { | |
2558 | const struct refsort *a = a_void; | |
2559 | const struct refsort *b = b_void; | |
2560 | ||
2561 | if (a->bytenr < b->bytenr) | |
2562 | return -1; | |
2563 | if (a->bytenr > b->bytenr) | |
2564 | return 1; | |
2565 | return 0; | |
2566 | } | |
2567 | #endif | |
2568 | ||
2569 | static int __btrfs_mod_ref(struct btrfs_trans_handle *trans, | |
2570 | struct btrfs_root *root, | |
2571 | struct extent_buffer *buf, | |
2572 | int full_backref, int inc) | |
2573 | { | |
2574 | u64 bytenr; | |
2575 | u64 num_bytes; | |
2576 | u64 parent; | |
2577 | u64 ref_root; | |
2578 | u32 nritems; | |
2579 | struct btrfs_key key; | |
2580 | struct btrfs_file_extent_item *fi; | |
2581 | int i; | |
2582 | int level; | |
2583 | int ret = 0; | |
2584 | int (*process_func)(struct btrfs_trans_handle *, struct btrfs_root *, | |
2585 | u64, u64, u64, u64, u64, u64); | |
2586 | ||
2587 | ref_root = btrfs_header_owner(buf); | |
2588 | nritems = btrfs_header_nritems(buf); | |
2589 | level = btrfs_header_level(buf); | |
2590 | ||
2591 | if (!root->ref_cows && level == 0) | |
2592 | return 0; | |
2593 | ||
2594 | if (inc) | |
2595 | process_func = btrfs_inc_extent_ref; | |
2596 | else | |
2597 | process_func = btrfs_free_extent; | |
2598 | ||
2599 | if (full_backref) | |
2600 | parent = buf->start; | |
2601 | else | |
2602 | parent = 0; | |
2603 | ||
2604 | for (i = 0; i < nritems; i++) { | |
2605 | if (level == 0) { | |
2606 | btrfs_item_key_to_cpu(buf, &key, i); | |
2607 | if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) | |
2608 | continue; | |
2609 | fi = btrfs_item_ptr(buf, i, | |
2610 | struct btrfs_file_extent_item); | |
2611 | if (btrfs_file_extent_type(buf, fi) == | |
2612 | BTRFS_FILE_EXTENT_INLINE) | |
2613 | continue; | |
2614 | bytenr = btrfs_file_extent_disk_bytenr(buf, fi); | |
2615 | if (bytenr == 0) | |
2616 | continue; | |
2617 | ||
2618 | num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi); | |
2619 | key.offset -= btrfs_file_extent_offset(buf, fi); | |
2620 | ret = process_func(trans, root, bytenr, num_bytes, | |
2621 | parent, ref_root, key.objectid, | |
2622 | key.offset); | |
2623 | if (ret) | |
2624 | goto fail; | |
2625 | } else { | |
2626 | bytenr = btrfs_node_blockptr(buf, i); | |
2627 | num_bytes = btrfs_level_size(root, level - 1); | |
2628 | ret = process_func(trans, root, bytenr, num_bytes, | |
2629 | parent, ref_root, level - 1, 0); | |
2630 | if (ret) | |
2631 | goto fail; | |
2632 | } | |
2633 | } | |
2634 | return 0; | |
2635 | fail: | |
2636 | BUG(); | |
2637 | return ret; | |
2638 | } | |
2639 | ||
2640 | int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, | |
2641 | struct extent_buffer *buf, int full_backref) | |
2642 | { | |
2643 | return __btrfs_mod_ref(trans, root, buf, full_backref, 1); | |
2644 | } | |
2645 | ||
2646 | int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, | |
2647 | struct extent_buffer *buf, int full_backref) | |
2648 | { | |
2649 | return __btrfs_mod_ref(trans, root, buf, full_backref, 0); | |
2650 | } | |
2651 | ||
2652 | static int write_one_cache_group(struct btrfs_trans_handle *trans, | |
2653 | struct btrfs_root *root, | |
2654 | struct btrfs_path *path, | |
2655 | struct btrfs_block_group_cache *cache) | |
2656 | { | |
2657 | int ret; | |
2658 | struct btrfs_root *extent_root = root->fs_info->extent_root; | |
2659 | unsigned long bi; | |
2660 | struct extent_buffer *leaf; | |
2661 | ||
2662 | ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1); | |
2663 | if (ret < 0) | |
2664 | goto fail; | |
2665 | BUG_ON(ret); | |
2666 | ||
2667 | leaf = path->nodes[0]; | |
2668 | bi = btrfs_item_ptr_offset(leaf, path->slots[0]); | |
2669 | write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item)); | |
2670 | btrfs_mark_buffer_dirty(leaf); | |
2671 | btrfs_release_path(extent_root, path); | |
2672 | fail: | |
2673 | if (ret) | |
2674 | return ret; | |
2675 | return 0; | |
2676 | ||
2677 | } | |
2678 | ||
2679 | static struct btrfs_block_group_cache * | |
2680 | next_block_group(struct btrfs_root *root, | |
2681 | struct btrfs_block_group_cache *cache) | |
2682 | { | |
2683 | struct rb_node *node; | |
2684 | spin_lock(&root->fs_info->block_group_cache_lock); | |
2685 | node = rb_next(&cache->cache_node); | |
2686 | btrfs_put_block_group(cache); | |
2687 | if (node) { | |
2688 | cache = rb_entry(node, struct btrfs_block_group_cache, | |
2689 | cache_node); | |
2690 | btrfs_get_block_group(cache); | |
2691 | } else | |
2692 | cache = NULL; | |
2693 | spin_unlock(&root->fs_info->block_group_cache_lock); | |
2694 | return cache; | |
2695 | } | |
2696 | ||
2697 | int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans, | |
2698 | struct btrfs_root *root) | |
2699 | { | |
2700 | struct btrfs_block_group_cache *cache; | |
2701 | int err = 0; | |
2702 | struct btrfs_path *path; | |
2703 | u64 last = 0; | |
2704 | ||
2705 | path = btrfs_alloc_path(); | |
2706 | if (!path) | |
2707 | return -ENOMEM; | |
2708 | ||
2709 | while (1) { | |
2710 | if (last == 0) { | |
2711 | err = btrfs_run_delayed_refs(trans, root, | |
2712 | (unsigned long)-1); | |
2713 | BUG_ON(err); | |
2714 | } | |
2715 | ||
2716 | cache = btrfs_lookup_first_block_group(root->fs_info, last); | |
2717 | while (cache) { | |
2718 | if (cache->dirty) | |
2719 | break; | |
2720 | cache = next_block_group(root, cache); | |
2721 | } | |
2722 | if (!cache) { | |
2723 | if (last == 0) | |
2724 | break; | |
2725 | last = 0; | |
2726 | continue; | |
2727 | } | |
2728 | ||
2729 | cache->dirty = 0; | |
2730 | last = cache->key.objectid + cache->key.offset; | |
2731 | ||
2732 | err = write_one_cache_group(trans, root, path, cache); | |
2733 | BUG_ON(err); | |
2734 | btrfs_put_block_group(cache); | |
2735 | } | |
2736 | ||
2737 | btrfs_free_path(path); | |
2738 | return 0; | |
2739 | } | |
2740 | ||
2741 | int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr) | |
2742 | { | |
2743 | struct btrfs_block_group_cache *block_group; | |
2744 | int readonly = 0; | |
2745 | ||
2746 | block_group = btrfs_lookup_block_group(root->fs_info, bytenr); | |
2747 | if (!block_group || block_group->ro) | |
2748 | readonly = 1; | |
2749 | if (block_group) | |
2750 | btrfs_put_block_group(block_group); | |
2751 | return readonly; | |
2752 | } | |
2753 | ||
2754 | static int update_space_info(struct btrfs_fs_info *info, u64 flags, | |
2755 | u64 total_bytes, u64 bytes_used, | |
2756 | struct btrfs_space_info **space_info) | |
2757 | { | |
2758 | struct btrfs_space_info *found; | |
2759 | int i; | |
2760 | int factor; | |
2761 | ||
2762 | if (flags & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 | | |
2763 | BTRFS_BLOCK_GROUP_RAID10)) | |
2764 | factor = 2; | |
2765 | else | |
2766 | factor = 1; | |
2767 | ||
2768 | found = __find_space_info(info, flags); | |
2769 | if (found) { | |
2770 | spin_lock(&found->lock); | |
2771 | found->total_bytes += total_bytes; | |
2772 | found->bytes_used += bytes_used; | |
2773 | found->disk_used += bytes_used * factor; | |
2774 | found->full = 0; | |
2775 | spin_unlock(&found->lock); | |
2776 | *space_info = found; | |
2777 | return 0; | |
2778 | } | |
2779 | found = kzalloc(sizeof(*found), GFP_NOFS); | |
2780 | if (!found) | |
2781 | return -ENOMEM; | |
2782 | ||
2783 | for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) | |
2784 | INIT_LIST_HEAD(&found->block_groups[i]); | |
2785 | init_rwsem(&found->groups_sem); | |
2786 | spin_lock_init(&found->lock); | |
2787 | found->flags = flags & (BTRFS_BLOCK_GROUP_DATA | | |
2788 | BTRFS_BLOCK_GROUP_SYSTEM | | |
2789 | BTRFS_BLOCK_GROUP_METADATA); | |
2790 | found->total_bytes = total_bytes; | |
2791 | found->bytes_used = bytes_used; | |
2792 | found->disk_used = bytes_used * factor; | |
2793 | found->bytes_pinned = 0; | |
2794 | found->bytes_reserved = 0; | |
2795 | found->bytes_readonly = 0; | |
2796 | found->bytes_may_use = 0; | |
2797 | found->full = 0; | |
2798 | found->force_alloc = 0; | |
2799 | *space_info = found; | |
2800 | list_add_rcu(&found->list, &info->space_info); | |
2801 | atomic_set(&found->caching_threads, 0); | |
2802 | return 0; | |
2803 | } | |
2804 | ||
2805 | static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags) | |
2806 | { | |
2807 | u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 | | |
2808 | BTRFS_BLOCK_GROUP_RAID1 | | |
2809 | BTRFS_BLOCK_GROUP_RAID10 | | |
2810 | BTRFS_BLOCK_GROUP_DUP); | |
2811 | if (extra_flags) { | |
2812 | if (flags & BTRFS_BLOCK_GROUP_DATA) | |
2813 | fs_info->avail_data_alloc_bits |= extra_flags; | |
2814 | if (flags & BTRFS_BLOCK_GROUP_METADATA) | |
2815 | fs_info->avail_metadata_alloc_bits |= extra_flags; | |
2816 | if (flags & BTRFS_BLOCK_GROUP_SYSTEM) | |
2817 | fs_info->avail_system_alloc_bits |= extra_flags; | |
2818 | } | |
2819 | } | |
2820 | ||
2821 | u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags) | |
2822 | { | |
2823 | u64 num_devices = root->fs_info->fs_devices->rw_devices; | |
2824 | ||
2825 | if (num_devices == 1) | |
2826 | flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0); | |
2827 | if (num_devices < 4) | |
2828 | flags &= ~BTRFS_BLOCK_GROUP_RAID10; | |
2829 | ||
2830 | if ((flags & BTRFS_BLOCK_GROUP_DUP) && | |
2831 | (flags & (BTRFS_BLOCK_GROUP_RAID1 | | |
2832 | BTRFS_BLOCK_GROUP_RAID10))) { | |
2833 | flags &= ~BTRFS_BLOCK_GROUP_DUP; | |
2834 | } | |
2835 | ||
2836 | if ((flags & BTRFS_BLOCK_GROUP_RAID1) && | |
2837 | (flags & BTRFS_BLOCK_GROUP_RAID10)) { | |
2838 | flags &= ~BTRFS_BLOCK_GROUP_RAID1; | |
2839 | } | |
2840 | ||
2841 | if ((flags & BTRFS_BLOCK_GROUP_RAID0) && | |
2842 | ((flags & BTRFS_BLOCK_GROUP_RAID1) | | |
2843 | (flags & BTRFS_BLOCK_GROUP_RAID10) | | |
2844 | (flags & BTRFS_BLOCK_GROUP_DUP))) | |
2845 | flags &= ~BTRFS_BLOCK_GROUP_RAID0; | |
2846 | return flags; | |
2847 | } | |
2848 | ||
2849 | static u64 get_alloc_profile(struct btrfs_root *root, u64 flags) | |
2850 | { | |
2851 | if (flags & BTRFS_BLOCK_GROUP_DATA) | |
2852 | flags |= root->fs_info->avail_data_alloc_bits & | |
2853 | root->fs_info->data_alloc_profile; | |
2854 | else if (flags & BTRFS_BLOCK_GROUP_SYSTEM) | |
2855 | flags |= root->fs_info->avail_system_alloc_bits & | |
2856 | root->fs_info->system_alloc_profile; | |
2857 | else if (flags & BTRFS_BLOCK_GROUP_METADATA) | |
2858 | flags |= root->fs_info->avail_metadata_alloc_bits & | |
2859 | root->fs_info->metadata_alloc_profile; | |
2860 | return btrfs_reduce_alloc_profile(root, flags); | |
2861 | } | |
2862 | ||
2863 | static u64 btrfs_get_alloc_profile(struct btrfs_root *root, int data) | |
2864 | { | |
2865 | u64 flags; | |
2866 | ||
2867 | if (data) | |
2868 | flags = BTRFS_BLOCK_GROUP_DATA; | |
2869 | else if (root == root->fs_info->chunk_root) | |
2870 | flags = BTRFS_BLOCK_GROUP_SYSTEM; | |
2871 | else | |
2872 | flags = BTRFS_BLOCK_GROUP_METADATA; | |
2873 | ||
2874 | return get_alloc_profile(root, flags); | |
2875 | } | |
2876 | ||
2877 | void btrfs_set_inode_space_info(struct btrfs_root *root, struct inode *inode) | |
2878 | { | |
2879 | BTRFS_I(inode)->space_info = __find_space_info(root->fs_info, | |
2880 | BTRFS_BLOCK_GROUP_DATA); | |
2881 | } | |
2882 | ||
2883 | static u64 calculate_bytes_needed(struct btrfs_root *root, int num_items) | |
2884 | { | |
2885 | u64 num_bytes; | |
2886 | int level; | |
2887 | ||
2888 | level = BTRFS_MAX_LEVEL - 2; | |
2889 | /* | |
2890 | * NOTE: these calculations are absolutely the worst possible case. | |
2891 | * This assumes that _every_ item we insert will require a new leaf, and | |
2892 | * that the tree has grown to its maximum level size. | |
2893 | */ | |
2894 | ||
2895 | /* | |
2896 | * for every item we insert we could insert both an extent item and a | |
2897 | * extent ref item. Then for ever item we insert, we will need to cow | |
2898 | * both the original leaf, plus the leaf to the left and right of it. | |
2899 | * | |
2900 | * Unless we are talking about the extent root, then we just want the | |
2901 | * number of items * 2, since we just need the extent item plus its ref. | |
2902 | */ | |
2903 | if (root == root->fs_info->extent_root) | |
2904 | num_bytes = num_items * 2; | |
2905 | else | |
2906 | num_bytes = (num_items + (2 * num_items)) * 3; | |
2907 | ||
2908 | /* | |
2909 | * num_bytes is total number of leaves we could need times the leaf | |
2910 | * size, and then for every leaf we could end up cow'ing 2 nodes per | |
2911 | * level, down to the leaf level. | |
2912 | */ | |
2913 | num_bytes = (num_bytes * root->leafsize) + | |
2914 | (num_bytes * (level * 2)) * root->nodesize; | |
2915 | ||
2916 | return num_bytes; | |
2917 | } | |
2918 | ||
2919 | /* | |
2920 | * Unreserve metadata space for delalloc. If we have less reserved credits than | |
2921 | * we have extents, this function does nothing. | |
2922 | */ | |
2923 | int btrfs_unreserve_metadata_for_delalloc(struct btrfs_root *root, | |
2924 | struct inode *inode, int num_items) | |
2925 | { | |
2926 | struct btrfs_fs_info *info = root->fs_info; | |
2927 | struct btrfs_space_info *meta_sinfo; | |
2928 | u64 num_bytes; | |
2929 | u64 alloc_target; | |
2930 | bool bug = false; | |
2931 | ||
2932 | /* get the space info for where the metadata will live */ | |
2933 | alloc_target = btrfs_get_alloc_profile(root, 0); | |
2934 | meta_sinfo = __find_space_info(info, alloc_target); | |
2935 | ||
2936 | num_bytes = calculate_bytes_needed(root->fs_info->extent_root, | |
2937 | num_items); | |
2938 | ||
2939 | spin_lock(&meta_sinfo->lock); | |
2940 | spin_lock(&BTRFS_I(inode)->accounting_lock); | |
2941 | if (BTRFS_I(inode)->reserved_extents <= | |
2942 | BTRFS_I(inode)->outstanding_extents) { | |
2943 | spin_unlock(&BTRFS_I(inode)->accounting_lock); | |
2944 | spin_unlock(&meta_sinfo->lock); | |
2945 | return 0; | |
2946 | } | |
2947 | spin_unlock(&BTRFS_I(inode)->accounting_lock); | |
2948 | ||
2949 | BTRFS_I(inode)->reserved_extents -= num_items; | |
2950 | BUG_ON(BTRFS_I(inode)->reserved_extents < 0); | |
2951 | ||
2952 | if (meta_sinfo->bytes_delalloc < num_bytes) { | |
2953 | bug = true; | |
2954 | meta_sinfo->bytes_delalloc = 0; | |
2955 | } else { | |
2956 | meta_sinfo->bytes_delalloc -= num_bytes; | |
2957 | } | |
2958 | spin_unlock(&meta_sinfo->lock); | |
2959 | ||
2960 | BUG_ON(bug); | |
2961 | ||
2962 | return 0; | |
2963 | } | |
2964 | ||
2965 | static void check_force_delalloc(struct btrfs_space_info *meta_sinfo) | |
2966 | { | |
2967 | u64 thresh; | |
2968 | ||
2969 | thresh = meta_sinfo->bytes_used + meta_sinfo->bytes_reserved + | |
2970 | meta_sinfo->bytes_pinned + meta_sinfo->bytes_readonly + | |
2971 | meta_sinfo->bytes_super + meta_sinfo->bytes_root + | |
2972 | meta_sinfo->bytes_may_use; | |
2973 | ||
2974 | thresh = meta_sinfo->total_bytes - thresh; | |
2975 | thresh *= 80; | |
2976 | do_div(thresh, 100); | |
2977 | if (thresh <= meta_sinfo->bytes_delalloc) | |
2978 | meta_sinfo->force_delalloc = 1; | |
2979 | else | |
2980 | meta_sinfo->force_delalloc = 0; | |
2981 | } | |
2982 | ||
2983 | /* | |
2984 | * Reserve metadata space for delalloc. | |
2985 | */ | |
2986 | int btrfs_reserve_metadata_for_delalloc(struct btrfs_root *root, | |
2987 | struct inode *inode, int num_items) | |
2988 | { | |
2989 | struct btrfs_fs_info *info = root->fs_info; | |
2990 | struct btrfs_space_info *meta_sinfo; | |
2991 | u64 num_bytes; | |
2992 | u64 used; | |
2993 | u64 alloc_target; | |
2994 | int flushed = 0; | |
2995 | int force_delalloc; | |
2996 | ||
2997 | /* get the space info for where the metadata will live */ | |
2998 | alloc_target = btrfs_get_alloc_profile(root, 0); | |
2999 | meta_sinfo = __find_space_info(info, alloc_target); | |
3000 | ||
3001 | num_bytes = calculate_bytes_needed(root->fs_info->extent_root, | |
3002 | num_items); | |
3003 | again: | |
3004 | spin_lock(&meta_sinfo->lock); | |
3005 | ||
3006 | force_delalloc = meta_sinfo->force_delalloc; | |
3007 | ||
3008 | if (unlikely(!meta_sinfo->bytes_root)) | |
3009 | meta_sinfo->bytes_root = calculate_bytes_needed(root, 6); | |
3010 | ||
3011 | if (!flushed) | |
3012 | meta_sinfo->bytes_delalloc += num_bytes; | |
3013 | ||
3014 | used = meta_sinfo->bytes_used + meta_sinfo->bytes_reserved + | |
3015 | meta_sinfo->bytes_pinned + meta_sinfo->bytes_readonly + | |
3016 | meta_sinfo->bytes_super + meta_sinfo->bytes_root + | |
3017 | meta_sinfo->bytes_may_use + meta_sinfo->bytes_delalloc; | |
3018 | ||
3019 | if (used > meta_sinfo->total_bytes) { | |
3020 | flushed++; | |
3021 | ||
3022 | if (flushed == 1) { | |
3023 | if (maybe_allocate_chunk(NULL, root, meta_sinfo, | |
3024 | num_bytes)) | |
3025 | goto again; | |
3026 | flushed++; | |
3027 | } else { | |
3028 | spin_unlock(&meta_sinfo->lock); | |
3029 | } | |
3030 | ||
3031 | if (flushed == 2) { | |
3032 | filemap_flush(inode->i_mapping); | |
3033 | goto again; | |
3034 | } else if (flushed == 3) { | |
3035 | shrink_delalloc(NULL, root, meta_sinfo, num_bytes); | |
3036 | goto again; | |
3037 | } | |
3038 | spin_lock(&meta_sinfo->lock); | |
3039 | meta_sinfo->bytes_delalloc -= num_bytes; | |
3040 | spin_unlock(&meta_sinfo->lock); | |
3041 | printk(KERN_ERR "enospc, has %d, reserved %d\n", | |
3042 | BTRFS_I(inode)->outstanding_extents, | |
3043 | BTRFS_I(inode)->reserved_extents); | |
3044 | dump_space_info(meta_sinfo, 0, 0); | |
3045 | return -ENOSPC; | |
3046 | } | |
3047 | ||
3048 | BTRFS_I(inode)->reserved_extents += num_items; | |
3049 | check_force_delalloc(meta_sinfo); | |
3050 | spin_unlock(&meta_sinfo->lock); | |
3051 | ||
3052 | if (!flushed && force_delalloc) | |
3053 | filemap_flush(inode->i_mapping); | |
3054 | ||
3055 | return 0; | |
3056 | } | |
3057 | ||
3058 | /* | |
3059 | * This will check the space that the inode allocates from to make sure we have | |
3060 | * enough space for bytes. | |
3061 | */ | |
3062 | int btrfs_check_data_free_space(struct btrfs_root *root, struct inode *inode, | |
3063 | u64 bytes) | |
3064 | { | |
3065 | struct btrfs_space_info *data_sinfo; | |
3066 | u64 used; | |
3067 | int ret = 0, committed = 0; | |
3068 | ||
3069 | /* make sure bytes are sectorsize aligned */ | |
3070 | bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1); | |
3071 | ||
3072 | data_sinfo = BTRFS_I(inode)->space_info; | |
3073 | if (!data_sinfo) | |
3074 | goto alloc; | |
3075 | ||
3076 | again: | |
3077 | /* make sure we have enough space to handle the data first */ | |
3078 | spin_lock(&data_sinfo->lock); | |
3079 | used = data_sinfo->bytes_used + data_sinfo->bytes_delalloc + | |
3080 | data_sinfo->bytes_reserved + data_sinfo->bytes_pinned + | |
3081 | data_sinfo->bytes_readonly + data_sinfo->bytes_may_use + | |
3082 | data_sinfo->bytes_super; | |
3083 | ||
3084 | if (used + bytes > data_sinfo->total_bytes) { | |
3085 | struct btrfs_trans_handle *trans; | |
3086 | ||
3087 | /* | |
3088 | * if we don't have enough free bytes in this space then we need | |
3089 | * to alloc a new chunk. | |
3090 | */ | |
3091 | if (!data_sinfo->full) { | |
3092 | u64 alloc_target; | |
3093 | ||
3094 | data_sinfo->force_alloc = 1; | |
3095 | spin_unlock(&data_sinfo->lock); | |
3096 | alloc: | |
3097 | alloc_target = btrfs_get_alloc_profile(root, 1); | |
3098 | trans = btrfs_join_transaction(root, 1); | |
3099 | if (IS_ERR(trans)) | |
3100 | return PTR_ERR(trans); | |
3101 | ||
3102 | ret = do_chunk_alloc(trans, root->fs_info->extent_root, | |
3103 | bytes + 2 * 1024 * 1024, | |
3104 | alloc_target, 0); | |
3105 | btrfs_end_transaction(trans, root); | |
3106 | if (ret) | |
3107 | return ret; | |
3108 | ||
3109 | if (!data_sinfo) { | |
3110 | btrfs_set_inode_space_info(root, inode); | |
3111 | data_sinfo = BTRFS_I(inode)->space_info; | |
3112 | } | |
3113 | goto again; | |
3114 | } | |
3115 | spin_unlock(&data_sinfo->lock); | |
3116 | ||
3117 | /* commit the current transaction and try again */ | |
3118 | if (!committed && !root->fs_info->open_ioctl_trans) { | |
3119 | committed = 1; | |
3120 | trans = btrfs_join_transaction(root, 1); | |
3121 | if (IS_ERR(trans)) | |
3122 | return PTR_ERR(trans); | |
3123 | ret = btrfs_commit_transaction(trans, root); | |
3124 | if (ret) | |
3125 | return ret; | |
3126 | goto again; | |
3127 | } | |
3128 | ||
3129 | printk(KERN_ERR "no space left, need %llu, %llu delalloc bytes" | |
3130 | ", %llu bytes_used, %llu bytes_reserved, " | |
3131 | "%llu bytes_pinned, %llu bytes_readonly, %llu may use " | |
3132 | "%llu total\n", (unsigned long long)bytes, | |
3133 | (unsigned long long)data_sinfo->bytes_delalloc, | |
3134 | (unsigned long long)data_sinfo->bytes_used, | |
3135 | (unsigned long long)data_sinfo->bytes_reserved, | |
3136 | (unsigned long long)data_sinfo->bytes_pinned, | |
3137 | (unsigned long long)data_sinfo->bytes_readonly, | |
3138 | (unsigned long long)data_sinfo->bytes_may_use, | |
3139 | (unsigned long long)data_sinfo->total_bytes); | |
3140 | return -ENOSPC; | |
3141 | } | |
3142 | data_sinfo->bytes_may_use += bytes; | |
3143 | BTRFS_I(inode)->reserved_bytes += bytes; | |
3144 | spin_unlock(&data_sinfo->lock); | |
3145 | ||
3146 | return 0; | |
3147 | } | |
3148 | ||
3149 | /* | |
3150 | * if there was an error for whatever reason after calling | |
3151 | * btrfs_check_data_free_space, call this so we can cleanup the counters. | |
3152 | */ | |
3153 | void btrfs_free_reserved_data_space(struct btrfs_root *root, | |
3154 | struct inode *inode, u64 bytes) | |
3155 | { | |
3156 | struct btrfs_space_info *data_sinfo; | |
3157 | ||
3158 | /* make sure bytes are sectorsize aligned */ | |
3159 | bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1); | |
3160 | ||
3161 | data_sinfo = BTRFS_I(inode)->space_info; | |
3162 | spin_lock(&data_sinfo->lock); | |
3163 | data_sinfo->bytes_may_use -= bytes; | |
3164 | BTRFS_I(inode)->reserved_bytes -= bytes; | |
3165 | spin_unlock(&data_sinfo->lock); | |
3166 | } | |
3167 | ||
3168 | /* called when we are adding a delalloc extent to the inode's io_tree */ | |
3169 | void btrfs_delalloc_reserve_space(struct btrfs_root *root, struct inode *inode, | |
3170 | u64 bytes) | |
3171 | { | |
3172 | struct btrfs_space_info *data_sinfo; | |
3173 | ||
3174 | /* get the space info for where this inode will be storing its data */ | |
3175 | data_sinfo = BTRFS_I(inode)->space_info; | |
3176 | ||
3177 | /* make sure we have enough space to handle the data first */ | |
3178 | spin_lock(&data_sinfo->lock); | |
3179 | data_sinfo->bytes_delalloc += bytes; | |
3180 | ||
3181 | /* | |
3182 | * we are adding a delalloc extent without calling | |
3183 | * btrfs_check_data_free_space first. This happens on a weird | |
3184 | * writepage condition, but shouldn't hurt our accounting | |
3185 | */ | |
3186 | if (unlikely(bytes > BTRFS_I(inode)->reserved_bytes)) { | |
3187 | data_sinfo->bytes_may_use -= BTRFS_I(inode)->reserved_bytes; | |
3188 | BTRFS_I(inode)->reserved_bytes = 0; | |
3189 | } else { | |
3190 | data_sinfo->bytes_may_use -= bytes; | |
3191 | BTRFS_I(inode)->reserved_bytes -= bytes; | |
3192 | } | |
3193 | ||
3194 | spin_unlock(&data_sinfo->lock); | |
3195 | } | |
3196 | ||
3197 | /* called when we are clearing an delalloc extent from the inode's io_tree */ | |
3198 | void btrfs_delalloc_free_space(struct btrfs_root *root, struct inode *inode, | |
3199 | u64 bytes) | |
3200 | { | |
3201 | struct btrfs_space_info *info; | |
3202 | ||
3203 | info = BTRFS_I(inode)->space_info; | |
3204 | ||
3205 | spin_lock(&info->lock); | |
3206 | info->bytes_delalloc -= bytes; | |
3207 | spin_unlock(&info->lock); | |
3208 | } | |
3209 | ||
3210 | static void force_metadata_allocation(struct btrfs_fs_info *info) | |
3211 | { | |
3212 | struct list_head *head = &info->space_info; | |
3213 | struct btrfs_space_info *found; | |
3214 | ||
3215 | rcu_read_lock(); | |
3216 | list_for_each_entry_rcu(found, head, list) { | |
3217 | if (found->flags & BTRFS_BLOCK_GROUP_METADATA) | |
3218 | found->force_alloc = 1; | |
3219 | } | |
3220 | rcu_read_unlock(); | |
3221 | } | |
3222 | ||
3223 | static int should_alloc_chunk(struct btrfs_space_info *sinfo, | |
3224 | u64 alloc_bytes) | |
3225 | { | |
3226 | u64 num_bytes = sinfo->total_bytes - sinfo->bytes_readonly; | |
3227 | ||
3228 | if (sinfo->bytes_used + sinfo->bytes_reserved + | |
3229 | alloc_bytes + 256 * 1024 * 1024 < num_bytes) | |
3230 | return 0; | |
3231 | ||
3232 | if (sinfo->bytes_used + sinfo->bytes_reserved + | |
3233 | alloc_bytes < div_factor(num_bytes, 8)) | |
3234 | return 0; | |
3235 | ||
3236 | return 1; | |
3237 | } | |
3238 | ||
3239 | static int do_chunk_alloc(struct btrfs_trans_handle *trans, | |
3240 | struct btrfs_root *extent_root, u64 alloc_bytes, | |
3241 | u64 flags, int force) | |
3242 | { | |
3243 | struct btrfs_space_info *space_info; | |
3244 | struct btrfs_fs_info *fs_info = extent_root->fs_info; | |
3245 | int ret = 0; | |
3246 | ||
3247 | mutex_lock(&fs_info->chunk_mutex); | |
3248 | ||
3249 | flags = btrfs_reduce_alloc_profile(extent_root, flags); | |
3250 | ||
3251 | space_info = __find_space_info(extent_root->fs_info, flags); | |
3252 | if (!space_info) { | |
3253 | ret = update_space_info(extent_root->fs_info, flags, | |
3254 | 0, 0, &space_info); | |
3255 | BUG_ON(ret); | |
3256 | } | |
3257 | BUG_ON(!space_info); | |
3258 | ||
3259 | spin_lock(&space_info->lock); | |
3260 | if (space_info->force_alloc) | |
3261 | force = 1; | |
3262 | if (space_info->full) { | |
3263 | spin_unlock(&space_info->lock); | |
3264 | goto out; | |
3265 | } | |
3266 | ||
3267 | if (!force && !should_alloc_chunk(space_info, alloc_bytes)) { | |
3268 | spin_unlock(&space_info->lock); | |
3269 | goto out; | |
3270 | } | |
3271 | spin_unlock(&space_info->lock); | |
3272 | ||
3273 | /* | |
3274 | * if we're doing a data chunk, go ahead and make sure that | |
3275 | * we keep a reasonable number of metadata chunks allocated in the | |
3276 | * FS as well. | |
3277 | */ | |
3278 | if (flags & BTRFS_BLOCK_GROUP_DATA && fs_info->metadata_ratio) { | |
3279 | fs_info->data_chunk_allocations++; | |
3280 | if (!(fs_info->data_chunk_allocations % | |
3281 | fs_info->metadata_ratio)) | |
3282 | force_metadata_allocation(fs_info); | |
3283 | } | |
3284 | ||
3285 | ret = btrfs_alloc_chunk(trans, extent_root, flags); | |
3286 | spin_lock(&space_info->lock); | |
3287 | if (ret) | |
3288 | space_info->full = 1; | |
3289 | else | |
3290 | ret = 1; | |
3291 | space_info->force_alloc = 0; | |
3292 | spin_unlock(&space_info->lock); | |
3293 | out: | |
3294 | mutex_unlock(&extent_root->fs_info->chunk_mutex); | |
3295 | return ret; | |
3296 | } | |
3297 | ||
3298 | static int maybe_allocate_chunk(struct btrfs_trans_handle *trans, | |
3299 | struct btrfs_root *root, | |
3300 | struct btrfs_space_info *sinfo, u64 num_bytes) | |
3301 | { | |
3302 | int ret; | |
3303 | int end_trans = 0; | |
3304 | ||
3305 | if (sinfo->full) | |
3306 | return 0; | |
3307 | ||
3308 | spin_lock(&sinfo->lock); | |
3309 | ret = should_alloc_chunk(sinfo, num_bytes + 2 * 1024 * 1024); | |
3310 | spin_unlock(&sinfo->lock); | |
3311 | if (!ret) | |
3312 | return 0; | |
3313 | ||
3314 | if (!trans) { | |
3315 | trans = btrfs_join_transaction(root, 1); | |
3316 | BUG_ON(IS_ERR(trans)); | |
3317 | end_trans = 1; | |
3318 | } | |
3319 | ||
3320 | ret = do_chunk_alloc(trans, root->fs_info->extent_root, | |
3321 | num_bytes + 2 * 1024 * 1024, | |
3322 | get_alloc_profile(root, sinfo->flags), 0); | |
3323 | ||
3324 | if (end_trans) | |
3325 | btrfs_end_transaction(trans, root); | |
3326 | ||
3327 | return ret == 1 ? 1 : 0; | |
3328 | } | |
3329 | ||
3330 | /* | |
3331 | * shrink metadata reservation for delalloc | |
3332 | */ | |
3333 | static int shrink_delalloc(struct btrfs_trans_handle *trans, | |
3334 | struct btrfs_root *root, | |
3335 | struct btrfs_space_info *sinfo, u64 to_reclaim) | |
3336 | { | |
3337 | u64 reserved; | |
3338 | u64 max_reclaim; | |
3339 | u64 reclaimed = 0; | |
3340 | int pause = 1; | |
3341 | int ret; | |
3342 | ||
3343 | spin_lock(&sinfo->lock); | |
3344 | reserved = sinfo->bytes_delalloc; | |
3345 | spin_unlock(&sinfo->lock); | |
3346 | ||
3347 | if (reserved == 0) | |
3348 | return 0; | |
3349 | ||
3350 | max_reclaim = min(reserved, to_reclaim); | |
3351 | ||
3352 | while (1) { | |
3353 | ret = btrfs_start_one_delalloc_inode(root, trans ? 1 : 0); | |
3354 | if (!ret) { | |
3355 | __set_current_state(TASK_INTERRUPTIBLE); | |
3356 | schedule_timeout(pause); | |
3357 | pause <<= 1; | |
3358 | if (pause > HZ / 10) | |
3359 | pause = HZ / 10; | |
3360 | } else { | |
3361 | pause = 1; | |
3362 | } | |
3363 | ||
3364 | spin_lock(&sinfo->lock); | |
3365 | if (reserved > sinfo->bytes_delalloc) | |
3366 | reclaimed = reserved - sinfo->bytes_delalloc; | |
3367 | reserved = sinfo->bytes_delalloc; | |
3368 | spin_unlock(&sinfo->lock); | |
3369 | ||
3370 | if (reserved == 0 || reclaimed >= max_reclaim) | |
3371 | break; | |
3372 | ||
3373 | if (trans && trans->transaction->blocked) | |
3374 | return -EAGAIN; | |
3375 | } | |
3376 | return reclaimed >= to_reclaim; | |
3377 | } | |
3378 | ||
3379 | static int should_retry_reserve(struct btrfs_trans_handle *trans, | |
3380 | struct btrfs_root *root, | |
3381 | struct btrfs_block_rsv *block_rsv, | |
3382 | u64 num_bytes, int *retries) | |
3383 | { | |
3384 | struct btrfs_space_info *space_info = block_rsv->space_info; | |
3385 | int ret; | |
3386 | ||
3387 | if ((*retries) > 2) | |
3388 | return -ENOSPC; | |
3389 | ||
3390 | ret = maybe_allocate_chunk(trans, root, space_info, num_bytes); | |
3391 | if (ret) | |
3392 | return 1; | |
3393 | ||
3394 | if (trans && trans->transaction->in_commit) | |
3395 | return -ENOSPC; | |
3396 | ||
3397 | ret = shrink_delalloc(trans, root, space_info, num_bytes); | |
3398 | if (ret) | |
3399 | return ret; | |
3400 | ||
3401 | spin_lock(&space_info->lock); | |
3402 | if (space_info->bytes_pinned < num_bytes) | |
3403 | ret = 1; | |
3404 | spin_unlock(&space_info->lock); | |
3405 | if (ret) | |
3406 | return -ENOSPC; | |
3407 | ||
3408 | (*retries)++; | |
3409 | ||
3410 | if (trans) | |
3411 | return -EAGAIN; | |
3412 | ||
3413 | trans = btrfs_join_transaction(root, 1); | |
3414 | BUG_ON(IS_ERR(trans)); | |
3415 | ret = btrfs_commit_transaction(trans, root); | |
3416 | BUG_ON(ret); | |
3417 | ||
3418 | return 1; | |
3419 | } | |
3420 | ||
3421 | static int reserve_metadata_bytes(struct btrfs_block_rsv *block_rsv, | |
3422 | u64 num_bytes) | |
3423 | { | |
3424 | struct btrfs_space_info *space_info = block_rsv->space_info; | |
3425 | u64 unused; | |
3426 | int ret = -ENOSPC; | |
3427 | ||
3428 | spin_lock(&space_info->lock); | |
3429 | unused = space_info->bytes_used + space_info->bytes_reserved + | |
3430 | space_info->bytes_pinned + space_info->bytes_readonly; | |
3431 | ||
3432 | if (unused < space_info->total_bytes) | |
3433 | unused = space_info->total_bytes - unused; | |
3434 | else | |
3435 | unused = 0; | |
3436 | ||
3437 | if (unused >= num_bytes) { | |
3438 | if (block_rsv->priority >= 10) { | |
3439 | space_info->bytes_reserved += num_bytes; | |
3440 | ret = 0; | |
3441 | } else { | |
3442 | if ((unused + block_rsv->reserved) * | |
3443 | block_rsv->priority >= | |
3444 | (num_bytes + block_rsv->reserved) * 10) { | |
3445 | space_info->bytes_reserved += num_bytes; | |
3446 | ret = 0; | |
3447 | } | |
3448 | } | |
3449 | } | |
3450 | spin_unlock(&space_info->lock); | |
3451 | ||
3452 | return ret; | |
3453 | } | |
3454 | ||
3455 | static struct btrfs_block_rsv *get_block_rsv(struct btrfs_trans_handle *trans, | |
3456 | struct btrfs_root *root) | |
3457 | { | |
3458 | struct btrfs_block_rsv *block_rsv; | |
3459 | if (root->ref_cows) | |
3460 | block_rsv = trans->block_rsv; | |
3461 | else | |
3462 | block_rsv = root->block_rsv; | |
3463 | ||
3464 | if (!block_rsv) | |
3465 | block_rsv = &root->fs_info->empty_block_rsv; | |
3466 | ||
3467 | return block_rsv; | |
3468 | } | |
3469 | ||
3470 | static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv, | |
3471 | u64 num_bytes) | |
3472 | { | |
3473 | int ret = -ENOSPC; | |
3474 | spin_lock(&block_rsv->lock); | |
3475 | if (block_rsv->reserved >= num_bytes) { | |
3476 | block_rsv->reserved -= num_bytes; | |
3477 | if (block_rsv->reserved < block_rsv->size) | |
3478 | block_rsv->full = 0; | |
3479 | ret = 0; | |
3480 | } | |
3481 | spin_unlock(&block_rsv->lock); | |
3482 | return ret; | |
3483 | } | |
3484 | ||
3485 | static void block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv, | |
3486 | u64 num_bytes, int update_size) | |
3487 | { | |
3488 | spin_lock(&block_rsv->lock); | |
3489 | block_rsv->reserved += num_bytes; | |
3490 | if (update_size) | |
3491 | block_rsv->size += num_bytes; | |
3492 | else if (block_rsv->reserved >= block_rsv->size) | |
3493 | block_rsv->full = 1; | |
3494 | spin_unlock(&block_rsv->lock); | |
3495 | } | |
3496 | ||
3497 | void block_rsv_release_bytes(struct btrfs_block_rsv *block_rsv, | |
3498 | struct btrfs_block_rsv *dest, u64 num_bytes) | |
3499 | { | |
3500 | struct btrfs_space_info *space_info = block_rsv->space_info; | |
3501 | ||
3502 | spin_lock(&block_rsv->lock); | |
3503 | if (num_bytes == (u64)-1) | |
3504 | num_bytes = block_rsv->size; | |
3505 | block_rsv->size -= num_bytes; | |
3506 | if (block_rsv->reserved >= block_rsv->size) { | |
3507 | num_bytes = block_rsv->reserved - block_rsv->size; | |
3508 | block_rsv->reserved = block_rsv->size; | |
3509 | block_rsv->full = 1; | |
3510 | } else { | |
3511 | num_bytes = 0; | |
3512 | } | |
3513 | spin_unlock(&block_rsv->lock); | |
3514 | ||
3515 | if (num_bytes > 0) { | |
3516 | if (dest) { | |
3517 | block_rsv_add_bytes(dest, num_bytes, 0); | |
3518 | } else { | |
3519 | spin_lock(&space_info->lock); | |
3520 | space_info->bytes_reserved -= num_bytes; | |
3521 | spin_unlock(&space_info->lock); | |
3522 | } | |
3523 | } | |
3524 | } | |
3525 | ||
3526 | static int block_rsv_migrate_bytes(struct btrfs_block_rsv *src, | |
3527 | struct btrfs_block_rsv *dst, u64 num_bytes) | |
3528 | { | |
3529 | int ret; | |
3530 | ||
3531 | ret = block_rsv_use_bytes(src, num_bytes); | |
3532 | if (ret) | |
3533 | return ret; | |
3534 | ||
3535 | block_rsv_add_bytes(dst, num_bytes, 1); | |
3536 | return 0; | |
3537 | } | |
3538 | ||
3539 | void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv) | |
3540 | { | |
3541 | memset(rsv, 0, sizeof(*rsv)); | |
3542 | spin_lock_init(&rsv->lock); | |
3543 | atomic_set(&rsv->usage, 1); | |
3544 | rsv->priority = 6; | |
3545 | INIT_LIST_HEAD(&rsv->list); | |
3546 | } | |
3547 | ||
3548 | struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_root *root) | |
3549 | { | |
3550 | struct btrfs_block_rsv *block_rsv; | |
3551 | struct btrfs_fs_info *fs_info = root->fs_info; | |
3552 | u64 alloc_target; | |
3553 | ||
3554 | block_rsv = kmalloc(sizeof(*block_rsv), GFP_NOFS); | |
3555 | if (!block_rsv) | |
3556 | return NULL; | |
3557 | ||
3558 | btrfs_init_block_rsv(block_rsv); | |
3559 | ||
3560 | alloc_target = btrfs_get_alloc_profile(root, 0); | |
3561 | block_rsv->space_info = __find_space_info(fs_info, | |
3562 | BTRFS_BLOCK_GROUP_METADATA); | |
3563 | ||
3564 | return block_rsv; | |
3565 | } | |
3566 | ||
3567 | void btrfs_free_block_rsv(struct btrfs_root *root, | |
3568 | struct btrfs_block_rsv *rsv) | |
3569 | { | |
3570 | if (rsv && atomic_dec_and_test(&rsv->usage)) { | |
3571 | btrfs_block_rsv_release(root, rsv, (u64)-1); | |
3572 | if (!rsv->durable) | |
3573 | kfree(rsv); | |
3574 | } | |
3575 | } | |
3576 | ||
3577 | /* | |
3578 | * make the block_rsv struct be able to capture freed space. | |
3579 | * the captured space will re-add to the the block_rsv struct | |
3580 | * after transaction commit | |
3581 | */ | |
3582 | void btrfs_add_durable_block_rsv(struct btrfs_fs_info *fs_info, | |
3583 | struct btrfs_block_rsv *block_rsv) | |
3584 | { | |
3585 | block_rsv->durable = 1; | |
3586 | mutex_lock(&fs_info->durable_block_rsv_mutex); | |
3587 | list_add_tail(&block_rsv->list, &fs_info->durable_block_rsv_list); | |
3588 | mutex_unlock(&fs_info->durable_block_rsv_mutex); | |
3589 | } | |
3590 | ||
3591 | int btrfs_block_rsv_add(struct btrfs_trans_handle *trans, | |
3592 | struct btrfs_root *root, | |
3593 | struct btrfs_block_rsv *block_rsv, | |
3594 | u64 num_bytes, int *retries) | |
3595 | { | |
3596 | int ret; | |
3597 | ||
3598 | if (num_bytes == 0) | |
3599 | return 0; | |
3600 | again: | |
3601 | ret = reserve_metadata_bytes(block_rsv, num_bytes); | |
3602 | if (!ret) { | |
3603 | block_rsv_add_bytes(block_rsv, num_bytes, 1); | |
3604 | return 0; | |
3605 | } | |
3606 | ||
3607 | ret = should_retry_reserve(trans, root, block_rsv, num_bytes, retries); | |
3608 | if (ret > 0) | |
3609 | goto again; | |
3610 | ||
3611 | return ret; | |
3612 | } | |
3613 | ||
3614 | int btrfs_block_rsv_check(struct btrfs_trans_handle *trans, | |
3615 | struct btrfs_root *root, | |
3616 | struct btrfs_block_rsv *block_rsv, | |
3617 | u64 min_reserved, int min_factor) | |
3618 | { | |
3619 | u64 num_bytes = 0; | |
3620 | int commit_trans = 0; | |
3621 | int ret = -ENOSPC; | |
3622 | ||
3623 | if (!block_rsv) | |
3624 | return 0; | |
3625 | ||
3626 | spin_lock(&block_rsv->lock); | |
3627 | if (min_factor > 0) | |
3628 | num_bytes = div_factor(block_rsv->size, min_factor); | |
3629 | if (min_reserved > num_bytes) | |
3630 | num_bytes = min_reserved; | |
3631 | ||
3632 | if (block_rsv->reserved >= num_bytes) { | |
3633 | ret = 0; | |
3634 | } else { | |
3635 | num_bytes -= block_rsv->reserved; | |
3636 | if (block_rsv->durable && | |
3637 | block_rsv->freed[0] + block_rsv->freed[1] >= num_bytes) | |
3638 | commit_trans = 1; | |
3639 | } | |
3640 | spin_unlock(&block_rsv->lock); | |
3641 | if (!ret) | |
3642 | return 0; | |
3643 | ||
3644 | if (block_rsv->refill_used) { | |
3645 | ret = reserve_metadata_bytes(block_rsv, num_bytes); | |
3646 | if (!ret) { | |
3647 | block_rsv_add_bytes(block_rsv, num_bytes, 0); | |
3648 | return 0; | |
3649 | } | |
3650 | } | |
3651 | ||
3652 | if (commit_trans) { | |
3653 | if (trans) | |
3654 | return -EAGAIN; | |
3655 | ||
3656 | trans = btrfs_join_transaction(root, 1); | |
3657 | BUG_ON(IS_ERR(trans)); | |
3658 | ret = btrfs_commit_transaction(trans, root); | |
3659 | return 0; | |
3660 | } | |
3661 | ||
3662 | WARN_ON(1); | |
3663 | printk(KERN_INFO"block_rsv size %llu reserved %llu freed %llu %llu\n", | |
3664 | block_rsv->size, block_rsv->reserved, | |
3665 | block_rsv->freed[0], block_rsv->freed[1]); | |
3666 | ||
3667 | return -ENOSPC; | |
3668 | } | |
3669 | ||
3670 | int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv, | |
3671 | struct btrfs_block_rsv *dst_rsv, | |
3672 | u64 num_bytes) | |
3673 | { | |
3674 | return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes); | |
3675 | } | |
3676 | ||
3677 | void btrfs_block_rsv_release(struct btrfs_root *root, | |
3678 | struct btrfs_block_rsv *block_rsv, | |
3679 | u64 num_bytes) | |
3680 | { | |
3681 | struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv; | |
3682 | if (global_rsv->full || global_rsv == block_rsv || | |
3683 | block_rsv->space_info != global_rsv->space_info) | |
3684 | global_rsv = NULL; | |
3685 | block_rsv_release_bytes(block_rsv, global_rsv, num_bytes); | |
3686 | } | |
3687 | ||
3688 | static void init_global_block_rsv(struct btrfs_fs_info *fs_info) | |
3689 | { | |
3690 | struct btrfs_space_info *space_info; | |
3691 | ||
3692 | space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM); | |
3693 | fs_info->chunk_block_rsv.space_info = space_info; | |
3694 | fs_info->chunk_block_rsv.priority = 10; | |
3695 | ||
3696 | space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA); | |
3697 | fs_info->trans_block_rsv.space_info = space_info; | |
3698 | fs_info->empty_block_rsv.space_info = space_info; | |
3699 | fs_info->empty_block_rsv.priority = 10; | |
3700 | ||
3701 | fs_info->chunk_root->block_rsv = &fs_info->chunk_block_rsv; | |
3702 | } | |
3703 | ||
3704 | static u64 calc_trans_metadata_size(struct btrfs_root *root, int num_items) | |
3705 | { | |
3706 | return (root->leafsize + root->nodesize * (BTRFS_MAX_LEVEL - 1)) * | |
3707 | 3 * num_items; | |
3708 | } | |
3709 | ||
3710 | int btrfs_trans_reserve_metadata(struct btrfs_trans_handle *trans, | |
3711 | struct btrfs_root *root, | |
3712 | int num_items, int *retries) | |
3713 | { | |
3714 | u64 num_bytes; | |
3715 | int ret; | |
3716 | ||
3717 | if (num_items == 0 || root->fs_info->chunk_root == root) | |
3718 | return 0; | |
3719 | ||
3720 | num_bytes = calc_trans_metadata_size(root, num_items); | |
3721 | ret = btrfs_block_rsv_add(trans, root, &root->fs_info->trans_block_rsv, | |
3722 | num_bytes, retries); | |
3723 | if (!ret) { | |
3724 | trans->bytes_reserved += num_bytes; | |
3725 | trans->block_rsv = &root->fs_info->trans_block_rsv; | |
3726 | } | |
3727 | return ret; | |
3728 | } | |
3729 | ||
3730 | void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans, | |
3731 | struct btrfs_root *root) | |
3732 | { | |
3733 | if (!trans->bytes_reserved) | |
3734 | return; | |
3735 | ||
3736 | BUG_ON(trans->block_rsv != &root->fs_info->trans_block_rsv); | |
3737 | btrfs_block_rsv_release(root, trans->block_rsv, | |
3738 | trans->bytes_reserved); | |
3739 | trans->bytes_reserved = 0; | |
3740 | } | |
3741 | ||
3742 | int btrfs_snap_reserve_metadata(struct btrfs_trans_handle *trans, | |
3743 | struct btrfs_pending_snapshot *pending) | |
3744 | { | |
3745 | struct btrfs_root *root = pending->root; | |
3746 | struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root); | |
3747 | struct btrfs_block_rsv *dst_rsv = &pending->block_rsv; | |
3748 | /* | |
3749 | * two for root back/forward refs, two for directory entries | |
3750 | * and one for root of the snapshot. | |
3751 | */ | |
3752 | u64 num_bytes = calc_trans_metadata_size(root, 5); | |
3753 | dst_rsv->space_info = src_rsv->space_info; | |
3754 | return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes); | |
3755 | } | |
3756 | ||
3757 | static int update_block_group(struct btrfs_trans_handle *trans, | |
3758 | struct btrfs_root *root, | |
3759 | u64 bytenr, u64 num_bytes, int alloc) | |
3760 | { | |
3761 | struct btrfs_block_group_cache *cache; | |
3762 | struct btrfs_fs_info *info = root->fs_info; | |
3763 | int factor; | |
3764 | u64 total = num_bytes; | |
3765 | u64 old_val; | |
3766 | u64 byte_in_group; | |
3767 | ||
3768 | /* block accounting for super block */ | |
3769 | spin_lock(&info->delalloc_lock); | |
3770 | old_val = btrfs_super_bytes_used(&info->super_copy); | |
3771 | if (alloc) | |
3772 | old_val += num_bytes; | |
3773 | else | |
3774 | old_val -= num_bytes; | |
3775 | btrfs_set_super_bytes_used(&info->super_copy, old_val); | |
3776 | spin_unlock(&info->delalloc_lock); | |
3777 | ||
3778 | while (total) { | |
3779 | cache = btrfs_lookup_block_group(info, bytenr); | |
3780 | if (!cache) | |
3781 | return -1; | |
3782 | if (cache->flags & (BTRFS_BLOCK_GROUP_DUP | | |
3783 | BTRFS_BLOCK_GROUP_RAID1 | | |
3784 | BTRFS_BLOCK_GROUP_RAID10)) | |
3785 | factor = 2; | |
3786 | else | |
3787 | factor = 1; | |
3788 | byte_in_group = bytenr - cache->key.objectid; | |
3789 | WARN_ON(byte_in_group > cache->key.offset); | |
3790 | ||
3791 | spin_lock(&cache->space_info->lock); | |
3792 | spin_lock(&cache->lock); | |
3793 | cache->dirty = 1; | |
3794 | old_val = btrfs_block_group_used(&cache->item); | |
3795 | num_bytes = min(total, cache->key.offset - byte_in_group); | |
3796 | if (alloc) { | |
3797 | old_val += num_bytes; | |
3798 | btrfs_set_block_group_used(&cache->item, old_val); | |
3799 | cache->reserved -= num_bytes; | |
3800 | cache->space_info->bytes_reserved -= num_bytes; | |
3801 | cache->space_info->bytes_used += num_bytes; | |
3802 | cache->space_info->disk_used += num_bytes * factor; | |
3803 | spin_unlock(&cache->lock); | |
3804 | spin_unlock(&cache->space_info->lock); | |
3805 | } else { | |
3806 | old_val -= num_bytes; | |
3807 | btrfs_set_block_group_used(&cache->item, old_val); | |
3808 | cache->pinned += num_bytes; | |
3809 | cache->space_info->bytes_pinned += num_bytes; | |
3810 | cache->space_info->bytes_used -= num_bytes; | |
3811 | cache->space_info->disk_used -= num_bytes * factor; | |
3812 | spin_unlock(&cache->lock); | |
3813 | spin_unlock(&cache->space_info->lock); | |
3814 | ||
3815 | set_extent_dirty(info->pinned_extents, | |
3816 | bytenr, bytenr + num_bytes - 1, | |
3817 | GFP_NOFS | __GFP_NOFAIL); | |
3818 | } | |
3819 | btrfs_put_block_group(cache); | |
3820 | total -= num_bytes; | |
3821 | bytenr += num_bytes; | |
3822 | } | |
3823 | return 0; | |
3824 | } | |
3825 | ||
3826 | static u64 first_logical_byte(struct btrfs_root *root, u64 search_start) | |
3827 | { | |
3828 | struct btrfs_block_group_cache *cache; | |
3829 | u64 bytenr; | |
3830 | ||
3831 | cache = btrfs_lookup_first_block_group(root->fs_info, search_start); | |
3832 | if (!cache) | |
3833 | return 0; | |
3834 | ||
3835 | bytenr = cache->key.objectid; | |
3836 | btrfs_put_block_group(cache); | |
3837 | ||
3838 | return bytenr; | |
3839 | } | |
3840 | ||
3841 | static int pin_down_extent(struct btrfs_root *root, | |
3842 | struct btrfs_block_group_cache *cache, | |
3843 | u64 bytenr, u64 num_bytes, int reserved) | |
3844 | { | |
3845 | spin_lock(&cache->space_info->lock); | |
3846 | spin_lock(&cache->lock); | |
3847 | cache->pinned += num_bytes; | |
3848 | cache->space_info->bytes_pinned += num_bytes; | |
3849 | if (reserved) { | |
3850 | cache->reserved -= num_bytes; | |
3851 | cache->space_info->bytes_reserved -= num_bytes; | |
3852 | } | |
3853 | spin_unlock(&cache->lock); | |
3854 | spin_unlock(&cache->space_info->lock); | |
3855 | ||
3856 | set_extent_dirty(root->fs_info->pinned_extents, bytenr, | |
3857 | bytenr + num_bytes - 1, GFP_NOFS | __GFP_NOFAIL); | |
3858 | return 0; | |
3859 | } | |
3860 | ||
3861 | /* | |
3862 | * this function must be called within transaction | |
3863 | */ | |
3864 | int btrfs_pin_extent(struct btrfs_root *root, | |
3865 | u64 bytenr, u64 num_bytes, int reserved) | |
3866 | { | |
3867 | struct btrfs_block_group_cache *cache; | |
3868 | ||
3869 | cache = btrfs_lookup_block_group(root->fs_info, bytenr); | |
3870 | BUG_ON(!cache); | |
3871 | ||
3872 | pin_down_extent(root, cache, bytenr, num_bytes, reserved); | |
3873 | ||
3874 | btrfs_put_block_group(cache); | |
3875 | return 0; | |
3876 | } | |
3877 | ||
3878 | /* | |
3879 | * update size of reserved extents. this function may return -EAGAIN | |
3880 | * if 'reserve' is true or 'sinfo' is false. | |
3881 | */ | |
3882 | static int update_reserved_bytes(struct btrfs_block_group_cache *cache, | |
3883 | u64 num_bytes, int reserve, int sinfo) | |
3884 | { | |
3885 | int ret = 0; | |
3886 | if (sinfo) { | |
3887 | struct btrfs_space_info *space_info = cache->space_info; | |
3888 | spin_lock(&space_info->lock); | |
3889 | spin_lock(&cache->lock); | |
3890 | if (reserve) { | |
3891 | if (cache->ro) { | |
3892 | ret = -EAGAIN; | |
3893 | } else { | |
3894 | cache->reserved += num_bytes; | |
3895 | space_info->bytes_reserved += num_bytes; | |
3896 | } | |
3897 | } else { | |
3898 | if (cache->ro) | |
3899 | space_info->bytes_readonly += num_bytes; | |
3900 | cache->reserved -= num_bytes; | |
3901 | space_info->bytes_reserved -= num_bytes; | |
3902 | } | |
3903 | spin_unlock(&cache->lock); | |
3904 | spin_unlock(&space_info->lock); | |
3905 | } else { | |
3906 | spin_lock(&cache->lock); | |
3907 | if (cache->ro) { | |
3908 | ret = -EAGAIN; | |
3909 | } else { | |
3910 | if (reserve) | |
3911 | cache->reserved += num_bytes; | |
3912 | else | |
3913 | cache->reserved -= num_bytes; | |
3914 | } | |
3915 | spin_unlock(&cache->lock); | |
3916 | } | |
3917 | return ret; | |
3918 | } | |
3919 | ||
3920 | int btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans, | |
3921 | struct btrfs_root *root) | |
3922 | { | |
3923 | struct btrfs_fs_info *fs_info = root->fs_info; | |
3924 | struct btrfs_caching_control *next; | |
3925 | struct btrfs_caching_control *caching_ctl; | |
3926 | struct btrfs_block_group_cache *cache; | |
3927 | ||
3928 | down_write(&fs_info->extent_commit_sem); | |
3929 | ||
3930 | list_for_each_entry_safe(caching_ctl, next, | |
3931 | &fs_info->caching_block_groups, list) { | |
3932 | cache = caching_ctl->block_group; | |
3933 | if (block_group_cache_done(cache)) { | |
3934 | cache->last_byte_to_unpin = (u64)-1; | |
3935 | list_del_init(&caching_ctl->list); | |
3936 | put_caching_control(caching_ctl); | |
3937 | } else { | |
3938 | cache->last_byte_to_unpin = caching_ctl->progress; | |
3939 | } | |
3940 | } | |
3941 | ||
3942 | if (fs_info->pinned_extents == &fs_info->freed_extents[0]) | |
3943 | fs_info->pinned_extents = &fs_info->freed_extents[1]; | |
3944 | else | |
3945 | fs_info->pinned_extents = &fs_info->freed_extents[0]; | |
3946 | ||
3947 | up_write(&fs_info->extent_commit_sem); | |
3948 | return 0; | |
3949 | } | |
3950 | ||
3951 | static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end) | |
3952 | { | |
3953 | struct btrfs_fs_info *fs_info = root->fs_info; | |
3954 | struct btrfs_block_group_cache *cache = NULL; | |
3955 | u64 len; | |
3956 | ||
3957 | while (start <= end) { | |
3958 | if (!cache || | |
3959 | start >= cache->key.objectid + cache->key.offset) { | |
3960 | if (cache) | |
3961 | btrfs_put_block_group(cache); | |
3962 | cache = btrfs_lookup_block_group(fs_info, start); | |
3963 | BUG_ON(!cache); | |
3964 | } | |
3965 | ||
3966 | len = cache->key.objectid + cache->key.offset - start; | |
3967 | len = min(len, end + 1 - start); | |
3968 | ||
3969 | if (start < cache->last_byte_to_unpin) { | |
3970 | len = min(len, cache->last_byte_to_unpin - start); | |
3971 | btrfs_add_free_space(cache, start, len); | |
3972 | } | |
3973 | ||
3974 | start += len; | |
3975 | ||
3976 | spin_lock(&cache->space_info->lock); | |
3977 | spin_lock(&cache->lock); | |
3978 | cache->pinned -= len; | |
3979 | cache->space_info->bytes_pinned -= len; | |
3980 | if (cache->ro) { | |
3981 | cache->space_info->bytes_readonly += len; | |
3982 | } else if (cache->reserved_pinned > 0) { | |
3983 | len = min(len, cache->reserved_pinned); | |
3984 | cache->reserved_pinned -= len; | |
3985 | cache->space_info->bytes_reserved += len; | |
3986 | } | |
3987 | spin_unlock(&cache->lock); | |
3988 | spin_unlock(&cache->space_info->lock); | |
3989 | } | |
3990 | ||
3991 | if (cache) | |
3992 | btrfs_put_block_group(cache); | |
3993 | return 0; | |
3994 | } | |
3995 | ||
3996 | int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans, | |
3997 | struct btrfs_root *root) | |
3998 | { | |
3999 | struct btrfs_fs_info *fs_info = root->fs_info; | |
4000 | struct extent_io_tree *unpin; | |
4001 | struct btrfs_block_rsv *block_rsv; | |
4002 | struct btrfs_block_rsv *next_rsv; | |
4003 | u64 start; | |
4004 | u64 end; | |
4005 | int idx; | |
4006 | int ret; | |
4007 | ||
4008 | if (fs_info->pinned_extents == &fs_info->freed_extents[0]) | |
4009 | unpin = &fs_info->freed_extents[1]; | |
4010 | else | |
4011 | unpin = &fs_info->freed_extents[0]; | |
4012 | ||
4013 | while (1) { | |
4014 | ret = find_first_extent_bit(unpin, 0, &start, &end, | |
4015 | EXTENT_DIRTY); | |
4016 | if (ret) | |
4017 | break; | |
4018 | ||
4019 | ret = btrfs_discard_extent(root, start, end + 1 - start); | |
4020 | ||
4021 | clear_extent_dirty(unpin, start, end, GFP_NOFS); | |
4022 | unpin_extent_range(root, start, end); | |
4023 | cond_resched(); | |
4024 | } | |
4025 | ||
4026 | mutex_lock(&fs_info->durable_block_rsv_mutex); | |
4027 | list_for_each_entry_safe(block_rsv, next_rsv, | |
4028 | &fs_info->durable_block_rsv_list, list) { | |
4029 | ||
4030 | idx = trans->transid & 0x1; | |
4031 | if (block_rsv->freed[idx] > 0) { | |
4032 | block_rsv_add_bytes(block_rsv, | |
4033 | block_rsv->freed[idx], 0); | |
4034 | block_rsv->freed[idx] = 0; | |
4035 | } | |
4036 | if (atomic_read(&block_rsv->usage) == 0) { | |
4037 | btrfs_block_rsv_release(root, block_rsv, (u64)-1); | |
4038 | ||
4039 | if (block_rsv->freed[0] == 0 && | |
4040 | block_rsv->freed[1] == 0) { | |
4041 | list_del_init(&block_rsv->list); | |
4042 | kfree(block_rsv); | |
4043 | } | |
4044 | } else { | |
4045 | btrfs_block_rsv_release(root, block_rsv, 0); | |
4046 | } | |
4047 | } | |
4048 | mutex_unlock(&fs_info->durable_block_rsv_mutex); | |
4049 | ||
4050 | return 0; | |
4051 | } | |
4052 | ||
4053 | static int __btrfs_free_extent(struct btrfs_trans_handle *trans, | |
4054 | struct btrfs_root *root, | |
4055 | u64 bytenr, u64 num_bytes, u64 parent, | |
4056 | u64 root_objectid, u64 owner_objectid, | |
4057 | u64 owner_offset, int refs_to_drop, | |
4058 | struct btrfs_delayed_extent_op *extent_op) | |
4059 | { | |
4060 | struct btrfs_key key; | |
4061 | struct btrfs_path *path; | |
4062 | struct btrfs_fs_info *info = root->fs_info; | |
4063 | struct btrfs_root *extent_root = info->extent_root; | |
4064 | struct extent_buffer *leaf; | |
4065 | struct btrfs_extent_item *ei; | |
4066 | struct btrfs_extent_inline_ref *iref; | |
4067 | int ret; | |
4068 | int is_data; | |
4069 | int extent_slot = 0; | |
4070 | int found_extent = 0; | |
4071 | int num_to_del = 1; | |
4072 | u32 item_size; | |
4073 | u64 refs; | |
4074 | ||
4075 | path = btrfs_alloc_path(); | |
4076 | if (!path) | |
4077 | return -ENOMEM; | |
4078 | ||
4079 | path->reada = 1; | |
4080 | path->leave_spinning = 1; | |
4081 | ||
4082 | is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID; | |
4083 | BUG_ON(!is_data && refs_to_drop != 1); | |
4084 | ||
4085 | ret = lookup_extent_backref(trans, extent_root, path, &iref, | |
4086 | bytenr, num_bytes, parent, | |
4087 | root_objectid, owner_objectid, | |
4088 | owner_offset); | |
4089 | if (ret == 0) { | |
4090 | extent_slot = path->slots[0]; | |
4091 | while (extent_slot >= 0) { | |
4092 | btrfs_item_key_to_cpu(path->nodes[0], &key, | |
4093 | extent_slot); | |
4094 | if (key.objectid != bytenr) | |
4095 | break; | |
4096 | if (key.type == BTRFS_EXTENT_ITEM_KEY && | |
4097 | key.offset == num_bytes) { | |
4098 | found_extent = 1; | |
4099 | break; | |
4100 | } | |
4101 | if (path->slots[0] - extent_slot > 5) | |
4102 | break; | |
4103 | extent_slot--; | |
4104 | } | |
4105 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
4106 | item_size = btrfs_item_size_nr(path->nodes[0], extent_slot); | |
4107 | if (found_extent && item_size < sizeof(*ei)) | |
4108 | found_extent = 0; | |
4109 | #endif | |
4110 | if (!found_extent) { | |
4111 | BUG_ON(iref); | |
4112 | ret = remove_extent_backref(trans, extent_root, path, | |
4113 | NULL, refs_to_drop, | |
4114 | is_data); | |
4115 | BUG_ON(ret); | |
4116 | btrfs_release_path(extent_root, path); | |
4117 | path->leave_spinning = 1; | |
4118 | ||
4119 | key.objectid = bytenr; | |
4120 | key.type = BTRFS_EXTENT_ITEM_KEY; | |
4121 | key.offset = num_bytes; | |
4122 | ||
4123 | ret = btrfs_search_slot(trans, extent_root, | |
4124 | &key, path, -1, 1); | |
4125 | if (ret) { | |
4126 | printk(KERN_ERR "umm, got %d back from search" | |
4127 | ", was looking for %llu\n", ret, | |
4128 | (unsigned long long)bytenr); | |
4129 | btrfs_print_leaf(extent_root, path->nodes[0]); | |
4130 | } | |
4131 | BUG_ON(ret); | |
4132 | extent_slot = path->slots[0]; | |
4133 | } | |
4134 | } else { | |
4135 | btrfs_print_leaf(extent_root, path->nodes[0]); | |
4136 | WARN_ON(1); | |
4137 | printk(KERN_ERR "btrfs unable to find ref byte nr %llu " | |
4138 | "parent %llu root %llu owner %llu offset %llu\n", | |
4139 | (unsigned long long)bytenr, | |
4140 | (unsigned long long)parent, | |
4141 | (unsigned long long)root_objectid, | |
4142 | (unsigned long long)owner_objectid, | |
4143 | (unsigned long long)owner_offset); | |
4144 | } | |
4145 | ||
4146 | leaf = path->nodes[0]; | |
4147 | item_size = btrfs_item_size_nr(leaf, extent_slot); | |
4148 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
4149 | if (item_size < sizeof(*ei)) { | |
4150 | BUG_ON(found_extent || extent_slot != path->slots[0]); | |
4151 | ret = convert_extent_item_v0(trans, extent_root, path, | |
4152 | owner_objectid, 0); | |
4153 | BUG_ON(ret < 0); | |
4154 | ||
4155 | btrfs_release_path(extent_root, path); | |
4156 | path->leave_spinning = 1; | |
4157 | ||
4158 | key.objectid = bytenr; | |
4159 | key.type = BTRFS_EXTENT_ITEM_KEY; | |
4160 | key.offset = num_bytes; | |
4161 | ||
4162 | ret = btrfs_search_slot(trans, extent_root, &key, path, | |
4163 | -1, 1); | |
4164 | if (ret) { | |
4165 | printk(KERN_ERR "umm, got %d back from search" | |
4166 | ", was looking for %llu\n", ret, | |
4167 | (unsigned long long)bytenr); | |
4168 | btrfs_print_leaf(extent_root, path->nodes[0]); | |
4169 | } | |
4170 | BUG_ON(ret); | |
4171 | extent_slot = path->slots[0]; | |
4172 | leaf = path->nodes[0]; | |
4173 | item_size = btrfs_item_size_nr(leaf, extent_slot); | |
4174 | } | |
4175 | #endif | |
4176 | BUG_ON(item_size < sizeof(*ei)); | |
4177 | ei = btrfs_item_ptr(leaf, extent_slot, | |
4178 | struct btrfs_extent_item); | |
4179 | if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID) { | |
4180 | struct btrfs_tree_block_info *bi; | |
4181 | BUG_ON(item_size < sizeof(*ei) + sizeof(*bi)); | |
4182 | bi = (struct btrfs_tree_block_info *)(ei + 1); | |
4183 | WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi)); | |
4184 | } | |
4185 | ||
4186 | refs = btrfs_extent_refs(leaf, ei); | |
4187 | BUG_ON(refs < refs_to_drop); | |
4188 | refs -= refs_to_drop; | |
4189 | ||
4190 | if (refs > 0) { | |
4191 | if (extent_op) | |
4192 | __run_delayed_extent_op(extent_op, leaf, ei); | |
4193 | /* | |
4194 | * In the case of inline back ref, reference count will | |
4195 | * be updated by remove_extent_backref | |
4196 | */ | |
4197 | if (iref) { | |
4198 | BUG_ON(!found_extent); | |
4199 | } else { | |
4200 | btrfs_set_extent_refs(leaf, ei, refs); | |
4201 | btrfs_mark_buffer_dirty(leaf); | |
4202 | } | |
4203 | if (found_extent) { | |
4204 | ret = remove_extent_backref(trans, extent_root, path, | |
4205 | iref, refs_to_drop, | |
4206 | is_data); | |
4207 | BUG_ON(ret); | |
4208 | } | |
4209 | } else { | |
4210 | if (found_extent) { | |
4211 | BUG_ON(is_data && refs_to_drop != | |
4212 | extent_data_ref_count(root, path, iref)); | |
4213 | if (iref) { | |
4214 | BUG_ON(path->slots[0] != extent_slot); | |
4215 | } else { | |
4216 | BUG_ON(path->slots[0] != extent_slot + 1); | |
4217 | path->slots[0] = extent_slot; | |
4218 | num_to_del = 2; | |
4219 | } | |
4220 | } | |
4221 | ||
4222 | ret = btrfs_del_items(trans, extent_root, path, path->slots[0], | |
4223 | num_to_del); | |
4224 | BUG_ON(ret); | |
4225 | btrfs_release_path(extent_root, path); | |
4226 | ||
4227 | if (is_data) { | |
4228 | ret = btrfs_del_csums(trans, root, bytenr, num_bytes); | |
4229 | BUG_ON(ret); | |
4230 | } else { | |
4231 | invalidate_mapping_pages(info->btree_inode->i_mapping, | |
4232 | bytenr >> PAGE_CACHE_SHIFT, | |
4233 | (bytenr + num_bytes - 1) >> PAGE_CACHE_SHIFT); | |
4234 | } | |
4235 | ||
4236 | ret = update_block_group(trans, root, bytenr, num_bytes, 0); | |
4237 | BUG_ON(ret); | |
4238 | } | |
4239 | btrfs_free_path(path); | |
4240 | return ret; | |
4241 | } | |
4242 | ||
4243 | /* | |
4244 | * when we free an block, it is possible (and likely) that we free the last | |
4245 | * delayed ref for that extent as well. This searches the delayed ref tree for | |
4246 | * a given extent, and if there are no other delayed refs to be processed, it | |
4247 | * removes it from the tree. | |
4248 | */ | |
4249 | static noinline int check_ref_cleanup(struct btrfs_trans_handle *trans, | |
4250 | struct btrfs_root *root, u64 bytenr) | |
4251 | { | |
4252 | struct btrfs_delayed_ref_head *head; | |
4253 | struct btrfs_delayed_ref_root *delayed_refs; | |
4254 | struct btrfs_delayed_ref_node *ref; | |
4255 | struct rb_node *node; | |
4256 | int ret = 0; | |
4257 | ||
4258 | delayed_refs = &trans->transaction->delayed_refs; | |
4259 | spin_lock(&delayed_refs->lock); | |
4260 | head = btrfs_find_delayed_ref_head(trans, bytenr); | |
4261 | if (!head) | |
4262 | goto out; | |
4263 | ||
4264 | node = rb_prev(&head->node.rb_node); | |
4265 | if (!node) | |
4266 | goto out; | |
4267 | ||
4268 | ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node); | |
4269 | ||
4270 | /* there are still entries for this ref, we can't drop it */ | |
4271 | if (ref->bytenr == bytenr) | |
4272 | goto out; | |
4273 | ||
4274 | if (head->extent_op) { | |
4275 | if (!head->must_insert_reserved) | |
4276 | goto out; | |
4277 | kfree(head->extent_op); | |
4278 | head->extent_op = NULL; | |
4279 | } | |
4280 | ||
4281 | /* | |
4282 | * waiting for the lock here would deadlock. If someone else has it | |
4283 | * locked they are already in the process of dropping it anyway | |
4284 | */ | |
4285 | if (!mutex_trylock(&head->mutex)) | |
4286 | goto out; | |
4287 | ||
4288 | /* | |
4289 | * at this point we have a head with no other entries. Go | |
4290 | * ahead and process it. | |
4291 | */ | |
4292 | head->node.in_tree = 0; | |
4293 | rb_erase(&head->node.rb_node, &delayed_refs->root); | |
4294 | ||
4295 | delayed_refs->num_entries--; | |
4296 | ||
4297 | /* | |
4298 | * we don't take a ref on the node because we're removing it from the | |
4299 | * tree, so we just steal the ref the tree was holding. | |
4300 | */ | |
4301 | delayed_refs->num_heads--; | |
4302 | if (list_empty(&head->cluster)) | |
4303 | delayed_refs->num_heads_ready--; | |
4304 | ||
4305 | list_del_init(&head->cluster); | |
4306 | spin_unlock(&delayed_refs->lock); | |
4307 | ||
4308 | BUG_ON(head->extent_op); | |
4309 | if (head->must_insert_reserved) | |
4310 | ret = 1; | |
4311 | ||
4312 | mutex_unlock(&head->mutex); | |
4313 | btrfs_put_delayed_ref(&head->node); | |
4314 | return ret; | |
4315 | out: | |
4316 | spin_unlock(&delayed_refs->lock); | |
4317 | return 0; | |
4318 | } | |
4319 | ||
4320 | void btrfs_free_tree_block(struct btrfs_trans_handle *trans, | |
4321 | struct btrfs_root *root, | |
4322 | struct extent_buffer *buf, | |
4323 | u64 parent, int last_ref) | |
4324 | { | |
4325 | struct btrfs_block_rsv *block_rsv; | |
4326 | struct btrfs_block_group_cache *cache = NULL; | |
4327 | int ret; | |
4328 | ||
4329 | if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) { | |
4330 | ret = btrfs_add_delayed_tree_ref(trans, buf->start, buf->len, | |
4331 | parent, root->root_key.objectid, | |
4332 | btrfs_header_level(buf), | |
4333 | BTRFS_DROP_DELAYED_REF, NULL); | |
4334 | BUG_ON(ret); | |
4335 | } | |
4336 | ||
4337 | if (!last_ref) | |
4338 | return; | |
4339 | ||
4340 | block_rsv = get_block_rsv(trans, root); | |
4341 | cache = btrfs_lookup_block_group(root->fs_info, buf->start); | |
4342 | BUG_ON(block_rsv->space_info != cache->space_info); | |
4343 | ||
4344 | if (btrfs_header_generation(buf) == trans->transid) { | |
4345 | if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) { | |
4346 | ret = check_ref_cleanup(trans, root, buf->start); | |
4347 | if (!ret) | |
4348 | goto pin; | |
4349 | } | |
4350 | ||
4351 | if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) { | |
4352 | pin_down_extent(root, cache, buf->start, buf->len, 1); | |
4353 | goto pin; | |
4354 | } | |
4355 | ||
4356 | WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)); | |
4357 | ||
4358 | btrfs_add_free_space(cache, buf->start, buf->len); | |
4359 | ret = update_reserved_bytes(cache, buf->len, 0, 0); | |
4360 | if (ret == -EAGAIN) { | |
4361 | /* block group became read-only */ | |
4362 | update_reserved_bytes(cache, buf->len, 0, 1); | |
4363 | goto out; | |
4364 | } | |
4365 | ||
4366 | ret = 1; | |
4367 | spin_lock(&block_rsv->lock); | |
4368 | if (block_rsv->reserved < block_rsv->size) { | |
4369 | block_rsv->reserved += buf->len; | |
4370 | ret = 0; | |
4371 | } | |
4372 | spin_unlock(&block_rsv->lock); | |
4373 | ||
4374 | if (ret) { | |
4375 | spin_lock(&cache->space_info->lock); | |
4376 | cache->space_info->bytes_reserved -= buf->len; | |
4377 | spin_unlock(&cache->space_info->lock); | |
4378 | } | |
4379 | goto out; | |
4380 | } | |
4381 | pin: | |
4382 | if (block_rsv->durable && !cache->ro) { | |
4383 | ret = 0; | |
4384 | spin_lock(&cache->lock); | |
4385 | if (!cache->ro) { | |
4386 | cache->reserved_pinned += buf->len; | |
4387 | ret = 1; | |
4388 | } | |
4389 | spin_unlock(&cache->lock); | |
4390 | ||
4391 | if (ret) { | |
4392 | spin_lock(&block_rsv->lock); | |
4393 | block_rsv->freed[trans->transid & 0x1] += buf->len; | |
4394 | spin_unlock(&block_rsv->lock); | |
4395 | } | |
4396 | } | |
4397 | out: | |
4398 | btrfs_put_block_group(cache); | |
4399 | } | |
4400 | ||
4401 | int btrfs_free_extent(struct btrfs_trans_handle *trans, | |
4402 | struct btrfs_root *root, | |
4403 | u64 bytenr, u64 num_bytes, u64 parent, | |
4404 | u64 root_objectid, u64 owner, u64 offset) | |
4405 | { | |
4406 | int ret; | |
4407 | ||
4408 | /* | |
4409 | * tree log blocks never actually go into the extent allocation | |
4410 | * tree, just update pinning info and exit early. | |
4411 | */ | |
4412 | if (root_objectid == BTRFS_TREE_LOG_OBJECTID) { | |
4413 | WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID); | |
4414 | /* unlocks the pinned mutex */ | |
4415 | btrfs_pin_extent(root, bytenr, num_bytes, 1); | |
4416 | ret = 0; | |
4417 | } else if (owner < BTRFS_FIRST_FREE_OBJECTID) { | |
4418 | ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes, | |
4419 | parent, root_objectid, (int)owner, | |
4420 | BTRFS_DROP_DELAYED_REF, NULL); | |
4421 | BUG_ON(ret); | |
4422 | } else { | |
4423 | ret = btrfs_add_delayed_data_ref(trans, bytenr, num_bytes, | |
4424 | parent, root_objectid, owner, | |
4425 | offset, BTRFS_DROP_DELAYED_REF, NULL); | |
4426 | BUG_ON(ret); | |
4427 | } | |
4428 | return ret; | |
4429 | } | |
4430 | ||
4431 | static u64 stripe_align(struct btrfs_root *root, u64 val) | |
4432 | { | |
4433 | u64 mask = ((u64)root->stripesize - 1); | |
4434 | u64 ret = (val + mask) & ~mask; | |
4435 | return ret; | |
4436 | } | |
4437 | ||
4438 | /* | |
4439 | * when we wait for progress in the block group caching, its because | |
4440 | * our allocation attempt failed at least once. So, we must sleep | |
4441 | * and let some progress happen before we try again. | |
4442 | * | |
4443 | * This function will sleep at least once waiting for new free space to | |
4444 | * show up, and then it will check the block group free space numbers | |
4445 | * for our min num_bytes. Another option is to have it go ahead | |
4446 | * and look in the rbtree for a free extent of a given size, but this | |
4447 | * is a good start. | |
4448 | */ | |
4449 | static noinline int | |
4450 | wait_block_group_cache_progress(struct btrfs_block_group_cache *cache, | |
4451 | u64 num_bytes) | |
4452 | { | |
4453 | struct btrfs_caching_control *caching_ctl; | |
4454 | DEFINE_WAIT(wait); | |
4455 | ||
4456 | caching_ctl = get_caching_control(cache); | |
4457 | if (!caching_ctl) | |
4458 | return 0; | |
4459 | ||
4460 | wait_event(caching_ctl->wait, block_group_cache_done(cache) || | |
4461 | (cache->free_space >= num_bytes)); | |
4462 | ||
4463 | put_caching_control(caching_ctl); | |
4464 | return 0; | |
4465 | } | |
4466 | ||
4467 | static noinline int | |
4468 | wait_block_group_cache_done(struct btrfs_block_group_cache *cache) | |
4469 | { | |
4470 | struct btrfs_caching_control *caching_ctl; | |
4471 | DEFINE_WAIT(wait); | |
4472 | ||
4473 | caching_ctl = get_caching_control(cache); | |
4474 | if (!caching_ctl) | |
4475 | return 0; | |
4476 | ||
4477 | wait_event(caching_ctl->wait, block_group_cache_done(cache)); | |
4478 | ||
4479 | put_caching_control(caching_ctl); | |
4480 | return 0; | |
4481 | } | |
4482 | ||
4483 | static int get_block_group_index(struct btrfs_block_group_cache *cache) | |
4484 | { | |
4485 | int index; | |
4486 | if (cache->flags & BTRFS_BLOCK_GROUP_RAID10) | |
4487 | index = 0; | |
4488 | else if (cache->flags & BTRFS_BLOCK_GROUP_RAID1) | |
4489 | index = 1; | |
4490 | else if (cache->flags & BTRFS_BLOCK_GROUP_DUP) | |
4491 | index = 2; | |
4492 | else if (cache->flags & BTRFS_BLOCK_GROUP_RAID0) | |
4493 | index = 3; | |
4494 | else | |
4495 | index = 4; | |
4496 | return index; | |
4497 | } | |
4498 | ||
4499 | enum btrfs_loop_type { | |
4500 | LOOP_FIND_IDEAL = 0, | |
4501 | LOOP_CACHING_NOWAIT = 1, | |
4502 | LOOP_CACHING_WAIT = 2, | |
4503 | LOOP_ALLOC_CHUNK = 3, | |
4504 | LOOP_NO_EMPTY_SIZE = 4, | |
4505 | }; | |
4506 | ||
4507 | /* | |
4508 | * walks the btree of allocated extents and find a hole of a given size. | |
4509 | * The key ins is changed to record the hole: | |
4510 | * ins->objectid == block start | |
4511 | * ins->flags = BTRFS_EXTENT_ITEM_KEY | |
4512 | * ins->offset == number of blocks | |
4513 | * Any available blocks before search_start are skipped. | |
4514 | */ | |
4515 | static noinline int find_free_extent(struct btrfs_trans_handle *trans, | |
4516 | struct btrfs_root *orig_root, | |
4517 | u64 num_bytes, u64 empty_size, | |
4518 | u64 search_start, u64 search_end, | |
4519 | u64 hint_byte, struct btrfs_key *ins, | |
4520 | int data) | |
4521 | { | |
4522 | int ret = 0; | |
4523 | struct btrfs_root *root = orig_root->fs_info->extent_root; | |
4524 | struct btrfs_free_cluster *last_ptr = NULL; | |
4525 | struct btrfs_block_group_cache *block_group = NULL; | |
4526 | int empty_cluster = 2 * 1024 * 1024; | |
4527 | int allowed_chunk_alloc = 0; | |
4528 | int done_chunk_alloc = 0; | |
4529 | struct btrfs_space_info *space_info; | |
4530 | int last_ptr_loop = 0; | |
4531 | int loop = 0; | |
4532 | int index = 0; | |
4533 | bool found_uncached_bg = false; | |
4534 | bool failed_cluster_refill = false; | |
4535 | bool failed_alloc = false; | |
4536 | u64 ideal_cache_percent = 0; | |
4537 | u64 ideal_cache_offset = 0; | |
4538 | ||
4539 | WARN_ON(num_bytes < root->sectorsize); | |
4540 | btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY); | |
4541 | ins->objectid = 0; | |
4542 | ins->offset = 0; | |
4543 | ||
4544 | space_info = __find_space_info(root->fs_info, data); | |
4545 | if (!space_info) { | |
4546 | printk(KERN_ERR "No space info for %d\n", data); | |
4547 | return -ENOSPC; | |
4548 | } | |
4549 | ||
4550 | if (orig_root->ref_cows || empty_size) | |
4551 | allowed_chunk_alloc = 1; | |
4552 | ||
4553 | if (data & BTRFS_BLOCK_GROUP_METADATA) { | |
4554 | last_ptr = &root->fs_info->meta_alloc_cluster; | |
4555 | if (!btrfs_test_opt(root, SSD)) | |
4556 | empty_cluster = 64 * 1024; | |
4557 | } | |
4558 | ||
4559 | if ((data & BTRFS_BLOCK_GROUP_DATA) && btrfs_test_opt(root, SSD)) { | |
4560 | last_ptr = &root->fs_info->data_alloc_cluster; | |
4561 | } | |
4562 | ||
4563 | if (last_ptr) { | |
4564 | spin_lock(&last_ptr->lock); | |
4565 | if (last_ptr->block_group) | |
4566 | hint_byte = last_ptr->window_start; | |
4567 | spin_unlock(&last_ptr->lock); | |
4568 | } | |
4569 | ||
4570 | search_start = max(search_start, first_logical_byte(root, 0)); | |
4571 | search_start = max(search_start, hint_byte); | |
4572 | ||
4573 | if (!last_ptr) | |
4574 | empty_cluster = 0; | |
4575 | ||
4576 | if (search_start == hint_byte) { | |
4577 | ideal_cache: | |
4578 | block_group = btrfs_lookup_block_group(root->fs_info, | |
4579 | search_start); | |
4580 | /* | |
4581 | * we don't want to use the block group if it doesn't match our | |
4582 | * allocation bits, or if its not cached. | |
4583 | * | |
4584 | * However if we are re-searching with an ideal block group | |
4585 | * picked out then we don't care that the block group is cached. | |
4586 | */ | |
4587 | if (block_group && block_group_bits(block_group, data) && | |
4588 | (block_group->cached != BTRFS_CACHE_NO || | |
4589 | search_start == ideal_cache_offset)) { | |
4590 | down_read(&space_info->groups_sem); | |
4591 | if (list_empty(&block_group->list) || | |
4592 | block_group->ro) { | |
4593 | /* | |
4594 | * someone is removing this block group, | |
4595 | * we can't jump into the have_block_group | |
4596 | * target because our list pointers are not | |
4597 | * valid | |
4598 | */ | |
4599 | btrfs_put_block_group(block_group); | |
4600 | up_read(&space_info->groups_sem); | |
4601 | } else { | |
4602 | index = get_block_group_index(block_group); | |
4603 | goto have_block_group; | |
4604 | } | |
4605 | } else if (block_group) { | |
4606 | btrfs_put_block_group(block_group); | |
4607 | } | |
4608 | } | |
4609 | search: | |
4610 | down_read(&space_info->groups_sem); | |
4611 | list_for_each_entry(block_group, &space_info->block_groups[index], | |
4612 | list) { | |
4613 | u64 offset; | |
4614 | int cached; | |
4615 | ||
4616 | btrfs_get_block_group(block_group); | |
4617 | search_start = block_group->key.objectid; | |
4618 | ||
4619 | have_block_group: | |
4620 | if (unlikely(block_group->cached == BTRFS_CACHE_NO)) { | |
4621 | u64 free_percent; | |
4622 | ||
4623 | free_percent = btrfs_block_group_used(&block_group->item); | |
4624 | free_percent *= 100; | |
4625 | free_percent = div64_u64(free_percent, | |
4626 | block_group->key.offset); | |
4627 | free_percent = 100 - free_percent; | |
4628 | if (free_percent > ideal_cache_percent && | |
4629 | likely(!block_group->ro)) { | |
4630 | ideal_cache_offset = block_group->key.objectid; | |
4631 | ideal_cache_percent = free_percent; | |
4632 | } | |
4633 | ||
4634 | /* | |
4635 | * We only want to start kthread caching if we are at | |
4636 | * the point where we will wait for caching to make | |
4637 | * progress, or if our ideal search is over and we've | |
4638 | * found somebody to start caching. | |
4639 | */ | |
4640 | if (loop > LOOP_CACHING_NOWAIT || | |
4641 | (loop > LOOP_FIND_IDEAL && | |
4642 | atomic_read(&space_info->caching_threads) < 2)) { | |
4643 | ret = cache_block_group(block_group); | |
4644 | BUG_ON(ret); | |
4645 | } | |
4646 | found_uncached_bg = true; | |
4647 | ||
4648 | /* | |
4649 | * If loop is set for cached only, try the next block | |
4650 | * group. | |
4651 | */ | |
4652 | if (loop == LOOP_FIND_IDEAL) | |
4653 | goto loop; | |
4654 | } | |
4655 | ||
4656 | cached = block_group_cache_done(block_group); | |
4657 | if (unlikely(!cached)) | |
4658 | found_uncached_bg = true; | |
4659 | ||
4660 | if (unlikely(block_group->ro)) | |
4661 | goto loop; | |
4662 | ||
4663 | /* | |
4664 | * Ok we want to try and use the cluster allocator, so lets look | |
4665 | * there, unless we are on LOOP_NO_EMPTY_SIZE, since we will | |
4666 | * have tried the cluster allocator plenty of times at this | |
4667 | * point and not have found anything, so we are likely way too | |
4668 | * fragmented for the clustering stuff to find anything, so lets | |
4669 | * just skip it and let the allocator find whatever block it can | |
4670 | * find | |
4671 | */ | |
4672 | if (last_ptr && loop < LOOP_NO_EMPTY_SIZE) { | |
4673 | /* | |
4674 | * the refill lock keeps out other | |
4675 | * people trying to start a new cluster | |
4676 | */ | |
4677 | spin_lock(&last_ptr->refill_lock); | |
4678 | if (last_ptr->block_group && | |
4679 | (last_ptr->block_group->ro || | |
4680 | !block_group_bits(last_ptr->block_group, data))) { | |
4681 | offset = 0; | |
4682 | goto refill_cluster; | |
4683 | } | |
4684 | ||
4685 | offset = btrfs_alloc_from_cluster(block_group, last_ptr, | |
4686 | num_bytes, search_start); | |
4687 | if (offset) { | |
4688 | /* we have a block, we're done */ | |
4689 | spin_unlock(&last_ptr->refill_lock); | |
4690 | goto checks; | |
4691 | } | |
4692 | ||
4693 | spin_lock(&last_ptr->lock); | |
4694 | /* | |
4695 | * whoops, this cluster doesn't actually point to | |
4696 | * this block group. Get a ref on the block | |
4697 | * group is does point to and try again | |
4698 | */ | |
4699 | if (!last_ptr_loop && last_ptr->block_group && | |
4700 | last_ptr->block_group != block_group) { | |
4701 | ||
4702 | btrfs_put_block_group(block_group); | |
4703 | block_group = last_ptr->block_group; | |
4704 | btrfs_get_block_group(block_group); | |
4705 | spin_unlock(&last_ptr->lock); | |
4706 | spin_unlock(&last_ptr->refill_lock); | |
4707 | ||
4708 | last_ptr_loop = 1; | |
4709 | search_start = block_group->key.objectid; | |
4710 | /* | |
4711 | * we know this block group is properly | |
4712 | * in the list because | |
4713 | * btrfs_remove_block_group, drops the | |
4714 | * cluster before it removes the block | |
4715 | * group from the list | |
4716 | */ | |
4717 | goto have_block_group; | |
4718 | } | |
4719 | spin_unlock(&last_ptr->lock); | |
4720 | refill_cluster: | |
4721 | /* | |
4722 | * this cluster didn't work out, free it and | |
4723 | * start over | |
4724 | */ | |
4725 | btrfs_return_cluster_to_free_space(NULL, last_ptr); | |
4726 | ||
4727 | last_ptr_loop = 0; | |
4728 | ||
4729 | /* allocate a cluster in this block group */ | |
4730 | ret = btrfs_find_space_cluster(trans, root, | |
4731 | block_group, last_ptr, | |
4732 | offset, num_bytes, | |
4733 | empty_cluster + empty_size); | |
4734 | if (ret == 0) { | |
4735 | /* | |
4736 | * now pull our allocation out of this | |
4737 | * cluster | |
4738 | */ | |
4739 | offset = btrfs_alloc_from_cluster(block_group, | |
4740 | last_ptr, num_bytes, | |
4741 | search_start); | |
4742 | if (offset) { | |
4743 | /* we found one, proceed */ | |
4744 | spin_unlock(&last_ptr->refill_lock); | |
4745 | goto checks; | |
4746 | } | |
4747 | } else if (!cached && loop > LOOP_CACHING_NOWAIT | |
4748 | && !failed_cluster_refill) { | |
4749 | spin_unlock(&last_ptr->refill_lock); | |
4750 | ||
4751 | failed_cluster_refill = true; | |
4752 | wait_block_group_cache_progress(block_group, | |
4753 | num_bytes + empty_cluster + empty_size); | |
4754 | goto have_block_group; | |
4755 | } | |
4756 | ||
4757 | /* | |
4758 | * at this point we either didn't find a cluster | |
4759 | * or we weren't able to allocate a block from our | |
4760 | * cluster. Free the cluster we've been trying | |
4761 | * to use, and go to the next block group | |
4762 | */ | |
4763 | btrfs_return_cluster_to_free_space(NULL, last_ptr); | |
4764 | spin_unlock(&last_ptr->refill_lock); | |
4765 | goto loop; | |
4766 | } | |
4767 | ||
4768 | offset = btrfs_find_space_for_alloc(block_group, search_start, | |
4769 | num_bytes, empty_size); | |
4770 | /* | |
4771 | * If we didn't find a chunk, and we haven't failed on this | |
4772 | * block group before, and this block group is in the middle of | |
4773 | * caching and we are ok with waiting, then go ahead and wait | |
4774 | * for progress to be made, and set failed_alloc to true. | |
4775 | * | |
4776 | * If failed_alloc is true then we've already waited on this | |
4777 | * block group once and should move on to the next block group. | |
4778 | */ | |
4779 | if (!offset && !failed_alloc && !cached && | |
4780 | loop > LOOP_CACHING_NOWAIT) { | |
4781 | wait_block_group_cache_progress(block_group, | |
4782 | num_bytes + empty_size); | |
4783 | failed_alloc = true; | |
4784 | goto have_block_group; | |
4785 | } else if (!offset) { | |
4786 | goto loop; | |
4787 | } | |
4788 | checks: | |
4789 | search_start = stripe_align(root, offset); | |
4790 | /* move on to the next group */ | |
4791 | if (search_start + num_bytes >= search_end) { | |
4792 | btrfs_add_free_space(block_group, offset, num_bytes); | |
4793 | goto loop; | |
4794 | } | |
4795 | ||
4796 | /* move on to the next group */ | |
4797 | if (search_start + num_bytes > | |
4798 | block_group->key.objectid + block_group->key.offset) { | |
4799 | btrfs_add_free_space(block_group, offset, num_bytes); | |
4800 | goto loop; | |
4801 | } | |
4802 | ||
4803 | ins->objectid = search_start; | |
4804 | ins->offset = num_bytes; | |
4805 | ||
4806 | if (offset < search_start) | |
4807 | btrfs_add_free_space(block_group, offset, | |
4808 | search_start - offset); | |
4809 | BUG_ON(offset > search_start); | |
4810 | ||
4811 | ret = update_reserved_bytes(block_group, num_bytes, 1, | |
4812 | (data & BTRFS_BLOCK_GROUP_DATA)); | |
4813 | if (ret == -EAGAIN) { | |
4814 | btrfs_add_free_space(block_group, offset, num_bytes); | |
4815 | goto loop; | |
4816 | } | |
4817 | ||
4818 | /* we are all good, lets return */ | |
4819 | ins->objectid = search_start; | |
4820 | ins->offset = num_bytes; | |
4821 | ||
4822 | if (offset < search_start) | |
4823 | btrfs_add_free_space(block_group, offset, | |
4824 | search_start - offset); | |
4825 | BUG_ON(offset > search_start); | |
4826 | break; | |
4827 | loop: | |
4828 | failed_cluster_refill = false; | |
4829 | failed_alloc = false; | |
4830 | BUG_ON(index != get_block_group_index(block_group)); | |
4831 | btrfs_put_block_group(block_group); | |
4832 | } | |
4833 | up_read(&space_info->groups_sem); | |
4834 | ||
4835 | if (!ins->objectid && ++index < BTRFS_NR_RAID_TYPES) | |
4836 | goto search; | |
4837 | ||
4838 | /* LOOP_FIND_IDEAL, only search caching/cached bg's, and don't wait for | |
4839 | * for them to make caching progress. Also | |
4840 | * determine the best possible bg to cache | |
4841 | * LOOP_CACHING_NOWAIT, search partially cached block groups, kicking | |
4842 | * caching kthreads as we move along | |
4843 | * LOOP_CACHING_WAIT, search everything, and wait if our bg is caching | |
4844 | * LOOP_ALLOC_CHUNK, force a chunk allocation and try again | |
4845 | * LOOP_NO_EMPTY_SIZE, set empty_size and empty_cluster to 0 and try | |
4846 | * again | |
4847 | */ | |
4848 | if (!ins->objectid && loop < LOOP_NO_EMPTY_SIZE && | |
4849 | (found_uncached_bg || empty_size || empty_cluster || | |
4850 | allowed_chunk_alloc)) { | |
4851 | index = 0; | |
4852 | if (loop == LOOP_FIND_IDEAL && found_uncached_bg) { | |
4853 | found_uncached_bg = false; | |
4854 | loop++; | |
4855 | if (!ideal_cache_percent && | |
4856 | atomic_read(&space_info->caching_threads)) | |
4857 | goto search; | |
4858 | ||
4859 | /* | |
4860 | * 1 of the following 2 things have happened so far | |
4861 | * | |
4862 | * 1) We found an ideal block group for caching that | |
4863 | * is mostly full and will cache quickly, so we might | |
4864 | * as well wait for it. | |
4865 | * | |
4866 | * 2) We searched for cached only and we didn't find | |
4867 | * anything, and we didn't start any caching kthreads | |
4868 | * either, so chances are we will loop through and | |
4869 | * start a couple caching kthreads, and then come back | |
4870 | * around and just wait for them. This will be slower | |
4871 | * because we will have 2 caching kthreads reading at | |
4872 | * the same time when we could have just started one | |
4873 | * and waited for it to get far enough to give us an | |
4874 | * allocation, so go ahead and go to the wait caching | |
4875 | * loop. | |
4876 | */ | |
4877 | loop = LOOP_CACHING_WAIT; | |
4878 | search_start = ideal_cache_offset; | |
4879 | ideal_cache_percent = 0; | |
4880 | goto ideal_cache; | |
4881 | } else if (loop == LOOP_FIND_IDEAL) { | |
4882 | /* | |
4883 | * Didn't find a uncached bg, wait on anything we find | |
4884 | * next. | |
4885 | */ | |
4886 | loop = LOOP_CACHING_WAIT; | |
4887 | goto search; | |
4888 | } | |
4889 | ||
4890 | if (loop < LOOP_CACHING_WAIT) { | |
4891 | loop++; | |
4892 | goto search; | |
4893 | } | |
4894 | ||
4895 | if (loop == LOOP_ALLOC_CHUNK) { | |
4896 | empty_size = 0; | |
4897 | empty_cluster = 0; | |
4898 | } | |
4899 | ||
4900 | if (allowed_chunk_alloc) { | |
4901 | ret = do_chunk_alloc(trans, root, num_bytes + | |
4902 | 2 * 1024 * 1024, data, 1); | |
4903 | allowed_chunk_alloc = 0; | |
4904 | done_chunk_alloc = 1; | |
4905 | } else if (!done_chunk_alloc) { | |
4906 | space_info->force_alloc = 1; | |
4907 | } | |
4908 | ||
4909 | if (loop < LOOP_NO_EMPTY_SIZE) { | |
4910 | loop++; | |
4911 | goto search; | |
4912 | } | |
4913 | ret = -ENOSPC; | |
4914 | } else if (!ins->objectid) { | |
4915 | ret = -ENOSPC; | |
4916 | } | |
4917 | ||
4918 | /* we found what we needed */ | |
4919 | if (ins->objectid) { | |
4920 | if (!(data & BTRFS_BLOCK_GROUP_DATA)) | |
4921 | trans->block_group = block_group->key.objectid; | |
4922 | ||
4923 | btrfs_put_block_group(block_group); | |
4924 | ret = 0; | |
4925 | } | |
4926 | ||
4927 | return ret; | |
4928 | } | |
4929 | ||
4930 | static void dump_space_info(struct btrfs_space_info *info, u64 bytes, | |
4931 | int dump_block_groups) | |
4932 | { | |
4933 | struct btrfs_block_group_cache *cache; | |
4934 | int index = 0; | |
4935 | ||
4936 | spin_lock(&info->lock); | |
4937 | printk(KERN_INFO "space_info has %llu free, is %sfull\n", | |
4938 | (unsigned long long)(info->total_bytes - info->bytes_used - | |
4939 | info->bytes_pinned - info->bytes_reserved - | |
4940 | info->bytes_super), | |
4941 | (info->full) ? "" : "not "); | |
4942 | printk(KERN_INFO "space_info total=%llu, pinned=%llu, delalloc=%llu," | |
4943 | " may_use=%llu, used=%llu, root=%llu, super=%llu, reserved=%llu" | |
4944 | "\n", | |
4945 | (unsigned long long)info->total_bytes, | |
4946 | (unsigned long long)info->bytes_pinned, | |
4947 | (unsigned long long)info->bytes_delalloc, | |
4948 | (unsigned long long)info->bytes_may_use, | |
4949 | (unsigned long long)info->bytes_used, | |
4950 | (unsigned long long)info->bytes_root, | |
4951 | (unsigned long long)info->bytes_super, | |
4952 | (unsigned long long)info->bytes_reserved); | |
4953 | spin_unlock(&info->lock); | |
4954 | ||
4955 | if (!dump_block_groups) | |
4956 | return; | |
4957 | ||
4958 | down_read(&info->groups_sem); | |
4959 | again: | |
4960 | list_for_each_entry(cache, &info->block_groups[index], list) { | |
4961 | spin_lock(&cache->lock); | |
4962 | printk(KERN_INFO "block group %llu has %llu bytes, %llu used " | |
4963 | "%llu pinned %llu reserved\n", | |
4964 | (unsigned long long)cache->key.objectid, | |
4965 | (unsigned long long)cache->key.offset, | |
4966 | (unsigned long long)btrfs_block_group_used(&cache->item), | |
4967 | (unsigned long long)cache->pinned, | |
4968 | (unsigned long long)cache->reserved); | |
4969 | btrfs_dump_free_space(cache, bytes); | |
4970 | spin_unlock(&cache->lock); | |
4971 | } | |
4972 | if (++index < BTRFS_NR_RAID_TYPES) | |
4973 | goto again; | |
4974 | up_read(&info->groups_sem); | |
4975 | } | |
4976 | ||
4977 | int btrfs_reserve_extent(struct btrfs_trans_handle *trans, | |
4978 | struct btrfs_root *root, | |
4979 | u64 num_bytes, u64 min_alloc_size, | |
4980 | u64 empty_size, u64 hint_byte, | |
4981 | u64 search_end, struct btrfs_key *ins, | |
4982 | u64 data) | |
4983 | { | |
4984 | int ret; | |
4985 | u64 search_start = 0; | |
4986 | ||
4987 | data = btrfs_get_alloc_profile(root, data); | |
4988 | again: | |
4989 | /* | |
4990 | * the only place that sets empty_size is btrfs_realloc_node, which | |
4991 | * is not called recursively on allocations | |
4992 | */ | |
4993 | if (empty_size || root->ref_cows) | |
4994 | ret = do_chunk_alloc(trans, root->fs_info->extent_root, | |
4995 | num_bytes + 2 * 1024 * 1024, data, 0); | |
4996 | ||
4997 | WARN_ON(num_bytes < root->sectorsize); | |
4998 | ret = find_free_extent(trans, root, num_bytes, empty_size, | |
4999 | search_start, search_end, hint_byte, | |
5000 | ins, data); | |
5001 | ||
5002 | if (ret == -ENOSPC && num_bytes > min_alloc_size) { | |
5003 | num_bytes = num_bytes >> 1; | |
5004 | num_bytes = num_bytes & ~(root->sectorsize - 1); | |
5005 | num_bytes = max(num_bytes, min_alloc_size); | |
5006 | do_chunk_alloc(trans, root->fs_info->extent_root, | |
5007 | num_bytes, data, 1); | |
5008 | goto again; | |
5009 | } | |
5010 | if (ret == -ENOSPC) { | |
5011 | struct btrfs_space_info *sinfo; | |
5012 | ||
5013 | sinfo = __find_space_info(root->fs_info, data); | |
5014 | printk(KERN_ERR "btrfs allocation failed flags %llu, " | |
5015 | "wanted %llu\n", (unsigned long long)data, | |
5016 | (unsigned long long)num_bytes); | |
5017 | dump_space_info(sinfo, num_bytes, 1); | |
5018 | } | |
5019 | ||
5020 | return ret; | |
5021 | } | |
5022 | ||
5023 | int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len) | |
5024 | { | |
5025 | struct btrfs_block_group_cache *cache; | |
5026 | int ret = 0; | |
5027 | ||
5028 | cache = btrfs_lookup_block_group(root->fs_info, start); | |
5029 | if (!cache) { | |
5030 | printk(KERN_ERR "Unable to find block group for %llu\n", | |
5031 | (unsigned long long)start); | |
5032 | return -ENOSPC; | |
5033 | } | |
5034 | ||
5035 | ret = btrfs_discard_extent(root, start, len); | |
5036 | ||
5037 | btrfs_add_free_space(cache, start, len); | |
5038 | update_reserved_bytes(cache, len, 0, 1); | |
5039 | btrfs_put_block_group(cache); | |
5040 | ||
5041 | return ret; | |
5042 | } | |
5043 | ||
5044 | static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans, | |
5045 | struct btrfs_root *root, | |
5046 | u64 parent, u64 root_objectid, | |
5047 | u64 flags, u64 owner, u64 offset, | |
5048 | struct btrfs_key *ins, int ref_mod) | |
5049 | { | |
5050 | int ret; | |
5051 | struct btrfs_fs_info *fs_info = root->fs_info; | |
5052 | struct btrfs_extent_item *extent_item; | |
5053 | struct btrfs_extent_inline_ref *iref; | |
5054 | struct btrfs_path *path; | |
5055 | struct extent_buffer *leaf; | |
5056 | int type; | |
5057 | u32 size; | |
5058 | ||
5059 | if (parent > 0) | |
5060 | type = BTRFS_SHARED_DATA_REF_KEY; | |
5061 | else | |
5062 | type = BTRFS_EXTENT_DATA_REF_KEY; | |
5063 | ||
5064 | size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type); | |
5065 | ||
5066 | path = btrfs_alloc_path(); | |
5067 | BUG_ON(!path); | |
5068 | ||
5069 | path->leave_spinning = 1; | |
5070 | ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path, | |
5071 | ins, size); | |
5072 | BUG_ON(ret); | |
5073 | ||
5074 | leaf = path->nodes[0]; | |
5075 | extent_item = btrfs_item_ptr(leaf, path->slots[0], | |
5076 | struct btrfs_extent_item); | |
5077 | btrfs_set_extent_refs(leaf, extent_item, ref_mod); | |
5078 | btrfs_set_extent_generation(leaf, extent_item, trans->transid); | |
5079 | btrfs_set_extent_flags(leaf, extent_item, | |
5080 | flags | BTRFS_EXTENT_FLAG_DATA); | |
5081 | ||
5082 | iref = (struct btrfs_extent_inline_ref *)(extent_item + 1); | |
5083 | btrfs_set_extent_inline_ref_type(leaf, iref, type); | |
5084 | if (parent > 0) { | |
5085 | struct btrfs_shared_data_ref *ref; | |
5086 | ref = (struct btrfs_shared_data_ref *)(iref + 1); | |
5087 | btrfs_set_extent_inline_ref_offset(leaf, iref, parent); | |
5088 | btrfs_set_shared_data_ref_count(leaf, ref, ref_mod); | |
5089 | } else { | |
5090 | struct btrfs_extent_data_ref *ref; | |
5091 | ref = (struct btrfs_extent_data_ref *)(&iref->offset); | |
5092 | btrfs_set_extent_data_ref_root(leaf, ref, root_objectid); | |
5093 | btrfs_set_extent_data_ref_objectid(leaf, ref, owner); | |
5094 | btrfs_set_extent_data_ref_offset(leaf, ref, offset); | |
5095 | btrfs_set_extent_data_ref_count(leaf, ref, ref_mod); | |
5096 | } | |
5097 | ||
5098 | btrfs_mark_buffer_dirty(path->nodes[0]); | |
5099 | btrfs_free_path(path); | |
5100 | ||
5101 | ret = update_block_group(trans, root, ins->objectid, ins->offset, 1); | |
5102 | if (ret) { | |
5103 | printk(KERN_ERR "btrfs update block group failed for %llu " | |
5104 | "%llu\n", (unsigned long long)ins->objectid, | |
5105 | (unsigned long long)ins->offset); | |
5106 | BUG(); | |
5107 | } | |
5108 | return ret; | |
5109 | } | |
5110 | ||
5111 | static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans, | |
5112 | struct btrfs_root *root, | |
5113 | u64 parent, u64 root_objectid, | |
5114 | u64 flags, struct btrfs_disk_key *key, | |
5115 | int level, struct btrfs_key *ins) | |
5116 | { | |
5117 | int ret; | |
5118 | struct btrfs_fs_info *fs_info = root->fs_info; | |
5119 | struct btrfs_extent_item *extent_item; | |
5120 | struct btrfs_tree_block_info *block_info; | |
5121 | struct btrfs_extent_inline_ref *iref; | |
5122 | struct btrfs_path *path; | |
5123 | struct extent_buffer *leaf; | |
5124 | u32 size = sizeof(*extent_item) + sizeof(*block_info) + sizeof(*iref); | |
5125 | ||
5126 | path = btrfs_alloc_path(); | |
5127 | BUG_ON(!path); | |
5128 | ||
5129 | path->leave_spinning = 1; | |
5130 | ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path, | |
5131 | ins, size); | |
5132 | BUG_ON(ret); | |
5133 | ||
5134 | leaf = path->nodes[0]; | |
5135 | extent_item = btrfs_item_ptr(leaf, path->slots[0], | |
5136 | struct btrfs_extent_item); | |
5137 | btrfs_set_extent_refs(leaf, extent_item, 1); | |
5138 | btrfs_set_extent_generation(leaf, extent_item, trans->transid); | |
5139 | btrfs_set_extent_flags(leaf, extent_item, | |
5140 | flags | BTRFS_EXTENT_FLAG_TREE_BLOCK); | |
5141 | block_info = (struct btrfs_tree_block_info *)(extent_item + 1); | |
5142 | ||
5143 | btrfs_set_tree_block_key(leaf, block_info, key); | |
5144 | btrfs_set_tree_block_level(leaf, block_info, level); | |
5145 | ||
5146 | iref = (struct btrfs_extent_inline_ref *)(block_info + 1); | |
5147 | if (parent > 0) { | |
5148 | BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)); | |
5149 | btrfs_set_extent_inline_ref_type(leaf, iref, | |
5150 | BTRFS_SHARED_BLOCK_REF_KEY); | |
5151 | btrfs_set_extent_inline_ref_offset(leaf, iref, parent); | |
5152 | } else { | |
5153 | btrfs_set_extent_inline_ref_type(leaf, iref, | |
5154 | BTRFS_TREE_BLOCK_REF_KEY); | |
5155 | btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid); | |
5156 | } | |
5157 | ||
5158 | btrfs_mark_buffer_dirty(leaf); | |
5159 | btrfs_free_path(path); | |
5160 | ||
5161 | ret = update_block_group(trans, root, ins->objectid, ins->offset, 1); | |
5162 | if (ret) { | |
5163 | printk(KERN_ERR "btrfs update block group failed for %llu " | |
5164 | "%llu\n", (unsigned long long)ins->objectid, | |
5165 | (unsigned long long)ins->offset); | |
5166 | BUG(); | |
5167 | } | |
5168 | return ret; | |
5169 | } | |
5170 | ||
5171 | int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans, | |
5172 | struct btrfs_root *root, | |
5173 | u64 root_objectid, u64 owner, | |
5174 | u64 offset, struct btrfs_key *ins) | |
5175 | { | |
5176 | int ret; | |
5177 | ||
5178 | BUG_ON(root_objectid == BTRFS_TREE_LOG_OBJECTID); | |
5179 | ||
5180 | ret = btrfs_add_delayed_data_ref(trans, ins->objectid, ins->offset, | |
5181 | 0, root_objectid, owner, offset, | |
5182 | BTRFS_ADD_DELAYED_EXTENT, NULL); | |
5183 | return ret; | |
5184 | } | |
5185 | ||
5186 | /* | |
5187 | * this is used by the tree logging recovery code. It records that | |
5188 | * an extent has been allocated and makes sure to clear the free | |
5189 | * space cache bits as well | |
5190 | */ | |
5191 | int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans, | |
5192 | struct btrfs_root *root, | |
5193 | u64 root_objectid, u64 owner, u64 offset, | |
5194 | struct btrfs_key *ins) | |
5195 | { | |
5196 | int ret; | |
5197 | struct btrfs_block_group_cache *block_group; | |
5198 | struct btrfs_caching_control *caching_ctl; | |
5199 | u64 start = ins->objectid; | |
5200 | u64 num_bytes = ins->offset; | |
5201 | ||
5202 | block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid); | |
5203 | cache_block_group(block_group); | |
5204 | caching_ctl = get_caching_control(block_group); | |
5205 | ||
5206 | if (!caching_ctl) { | |
5207 | BUG_ON(!block_group_cache_done(block_group)); | |
5208 | ret = btrfs_remove_free_space(block_group, start, num_bytes); | |
5209 | BUG_ON(ret); | |
5210 | } else { | |
5211 | mutex_lock(&caching_ctl->mutex); | |
5212 | ||
5213 | if (start >= caching_ctl->progress) { | |
5214 | ret = add_excluded_extent(root, start, num_bytes); | |
5215 | BUG_ON(ret); | |
5216 | } else if (start + num_bytes <= caching_ctl->progress) { | |
5217 | ret = btrfs_remove_free_space(block_group, | |
5218 | start, num_bytes); | |
5219 | BUG_ON(ret); | |
5220 | } else { | |
5221 | num_bytes = caching_ctl->progress - start; | |
5222 | ret = btrfs_remove_free_space(block_group, | |
5223 | start, num_bytes); | |
5224 | BUG_ON(ret); | |
5225 | ||
5226 | start = caching_ctl->progress; | |
5227 | num_bytes = ins->objectid + ins->offset - | |
5228 | caching_ctl->progress; | |
5229 | ret = add_excluded_extent(root, start, num_bytes); | |
5230 | BUG_ON(ret); | |
5231 | } | |
5232 | ||
5233 | mutex_unlock(&caching_ctl->mutex); | |
5234 | put_caching_control(caching_ctl); | |
5235 | } | |
5236 | ||
5237 | ret = update_reserved_bytes(block_group, ins->offset, 1, 1); | |
5238 | BUG_ON(ret); | |
5239 | btrfs_put_block_group(block_group); | |
5240 | ret = alloc_reserved_file_extent(trans, root, 0, root_objectid, | |
5241 | 0, owner, offset, ins, 1); | |
5242 | return ret; | |
5243 | } | |
5244 | ||
5245 | struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans, | |
5246 | struct btrfs_root *root, | |
5247 | u64 bytenr, u32 blocksize, | |
5248 | int level) | |
5249 | { | |
5250 | struct extent_buffer *buf; | |
5251 | ||
5252 | buf = btrfs_find_create_tree_block(root, bytenr, blocksize); | |
5253 | if (!buf) | |
5254 | return ERR_PTR(-ENOMEM); | |
5255 | btrfs_set_header_generation(buf, trans->transid); | |
5256 | btrfs_set_buffer_lockdep_class(buf, level); | |
5257 | btrfs_tree_lock(buf); | |
5258 | clean_tree_block(trans, root, buf); | |
5259 | ||
5260 | btrfs_set_lock_blocking(buf); | |
5261 | btrfs_set_buffer_uptodate(buf); | |
5262 | ||
5263 | if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) { | |
5264 | /* | |
5265 | * we allow two log transactions at a time, use different | |
5266 | * EXENT bit to differentiate dirty pages. | |
5267 | */ | |
5268 | if (root->log_transid % 2 == 0) | |
5269 | set_extent_dirty(&root->dirty_log_pages, buf->start, | |
5270 | buf->start + buf->len - 1, GFP_NOFS); | |
5271 | else | |
5272 | set_extent_new(&root->dirty_log_pages, buf->start, | |
5273 | buf->start + buf->len - 1, GFP_NOFS); | |
5274 | } else { | |
5275 | set_extent_dirty(&trans->transaction->dirty_pages, buf->start, | |
5276 | buf->start + buf->len - 1, GFP_NOFS); | |
5277 | } | |
5278 | trans->blocks_used++; | |
5279 | /* this returns a buffer locked for blocking */ | |
5280 | return buf; | |
5281 | } | |
5282 | ||
5283 | static struct btrfs_block_rsv * | |
5284 | use_block_rsv(struct btrfs_trans_handle *trans, | |
5285 | struct btrfs_root *root, u32 blocksize) | |
5286 | { | |
5287 | struct btrfs_block_rsv *block_rsv; | |
5288 | int ret; | |
5289 | ||
5290 | block_rsv = get_block_rsv(trans, root); | |
5291 | ||
5292 | if (block_rsv->size == 0) { | |
5293 | ret = reserve_metadata_bytes(block_rsv, blocksize); | |
5294 | if (ret) | |
5295 | return ERR_PTR(ret); | |
5296 | return block_rsv; | |
5297 | } | |
5298 | ||
5299 | ret = block_rsv_use_bytes(block_rsv, blocksize); | |
5300 | if (!ret) | |
5301 | return block_rsv; | |
5302 | ||
5303 | WARN_ON(1); | |
5304 | printk(KERN_INFO"block_rsv size %llu reserved %llu freed %llu %llu\n", | |
5305 | block_rsv->size, block_rsv->reserved, | |
5306 | block_rsv->freed[0], block_rsv->freed[1]); | |
5307 | ||
5308 | return ERR_PTR(-ENOSPC); | |
5309 | } | |
5310 | ||
5311 | static void unuse_block_rsv(struct btrfs_block_rsv *block_rsv, u32 blocksize) | |
5312 | { | |
5313 | block_rsv_add_bytes(block_rsv, blocksize, 0); | |
5314 | block_rsv_release_bytes(block_rsv, NULL, 0); | |
5315 | } | |
5316 | ||
5317 | /* | |
5318 | * finds a free extent and does all the dirty work required for allocation | |
5319 | * returns the key for the extent through ins, and a tree buffer for | |
5320 | * the first block of the extent through buf. | |
5321 | * | |
5322 | * returns the tree buffer or NULL. | |
5323 | */ | |
5324 | struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans, | |
5325 | struct btrfs_root *root, u32 blocksize, | |
5326 | u64 parent, u64 root_objectid, | |
5327 | struct btrfs_disk_key *key, int level, | |
5328 | u64 hint, u64 empty_size) | |
5329 | { | |
5330 | struct btrfs_key ins; | |
5331 | struct btrfs_block_rsv *block_rsv; | |
5332 | struct extent_buffer *buf; | |
5333 | u64 flags = 0; | |
5334 | int ret; | |
5335 | ||
5336 | ||
5337 | block_rsv = use_block_rsv(trans, root, blocksize); | |
5338 | if (IS_ERR(block_rsv)) | |
5339 | return ERR_CAST(block_rsv); | |
5340 | ||
5341 | ret = btrfs_reserve_extent(trans, root, blocksize, blocksize, | |
5342 | empty_size, hint, (u64)-1, &ins, 0); | |
5343 | if (ret) { | |
5344 | unuse_block_rsv(block_rsv, blocksize); | |
5345 | return ERR_PTR(ret); | |
5346 | } | |
5347 | ||
5348 | buf = btrfs_init_new_buffer(trans, root, ins.objectid, | |
5349 | blocksize, level); | |
5350 | BUG_ON(IS_ERR(buf)); | |
5351 | ||
5352 | if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) { | |
5353 | if (parent == 0) | |
5354 | parent = ins.objectid; | |
5355 | flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF; | |
5356 | } else | |
5357 | BUG_ON(parent > 0); | |
5358 | ||
5359 | if (root_objectid != BTRFS_TREE_LOG_OBJECTID) { | |
5360 | struct btrfs_delayed_extent_op *extent_op; | |
5361 | extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS); | |
5362 | BUG_ON(!extent_op); | |
5363 | if (key) | |
5364 | memcpy(&extent_op->key, key, sizeof(extent_op->key)); | |
5365 | else | |
5366 | memset(&extent_op->key, 0, sizeof(extent_op->key)); | |
5367 | extent_op->flags_to_set = flags; | |
5368 | extent_op->update_key = 1; | |
5369 | extent_op->update_flags = 1; | |
5370 | extent_op->is_data = 0; | |
5371 | ||
5372 | ret = btrfs_add_delayed_tree_ref(trans, ins.objectid, | |
5373 | ins.offset, parent, root_objectid, | |
5374 | level, BTRFS_ADD_DELAYED_EXTENT, | |
5375 | extent_op); | |
5376 | BUG_ON(ret); | |
5377 | } | |
5378 | return buf; | |
5379 | } | |
5380 | ||
5381 | struct walk_control { | |
5382 | u64 refs[BTRFS_MAX_LEVEL]; | |
5383 | u64 flags[BTRFS_MAX_LEVEL]; | |
5384 | struct btrfs_key update_progress; | |
5385 | int stage; | |
5386 | int level; | |
5387 | int shared_level; | |
5388 | int update_ref; | |
5389 | int keep_locks; | |
5390 | int reada_slot; | |
5391 | int reada_count; | |
5392 | }; | |
5393 | ||
5394 | #define DROP_REFERENCE 1 | |
5395 | #define UPDATE_BACKREF 2 | |
5396 | ||
5397 | static noinline void reada_walk_down(struct btrfs_trans_handle *trans, | |
5398 | struct btrfs_root *root, | |
5399 | struct walk_control *wc, | |
5400 | struct btrfs_path *path) | |
5401 | { | |
5402 | u64 bytenr; | |
5403 | u64 generation; | |
5404 | u64 refs; | |
5405 | u64 flags; | |
5406 | u64 last = 0; | |
5407 | u32 nritems; | |
5408 | u32 blocksize; | |
5409 | struct btrfs_key key; | |
5410 | struct extent_buffer *eb; | |
5411 | int ret; | |
5412 | int slot; | |
5413 | int nread = 0; | |
5414 | ||
5415 | if (path->slots[wc->level] < wc->reada_slot) { | |
5416 | wc->reada_count = wc->reada_count * 2 / 3; | |
5417 | wc->reada_count = max(wc->reada_count, 2); | |
5418 | } else { | |
5419 | wc->reada_count = wc->reada_count * 3 / 2; | |
5420 | wc->reada_count = min_t(int, wc->reada_count, | |
5421 | BTRFS_NODEPTRS_PER_BLOCK(root)); | |
5422 | } | |
5423 | ||
5424 | eb = path->nodes[wc->level]; | |
5425 | nritems = btrfs_header_nritems(eb); | |
5426 | blocksize = btrfs_level_size(root, wc->level - 1); | |
5427 | ||
5428 | for (slot = path->slots[wc->level]; slot < nritems; slot++) { | |
5429 | if (nread >= wc->reada_count) | |
5430 | break; | |
5431 | ||
5432 | cond_resched(); | |
5433 | bytenr = btrfs_node_blockptr(eb, slot); | |
5434 | generation = btrfs_node_ptr_generation(eb, slot); | |
5435 | ||
5436 | if (slot == path->slots[wc->level]) | |
5437 | goto reada; | |
5438 | ||
5439 | if (wc->stage == UPDATE_BACKREF && | |
5440 | generation <= root->root_key.offset) | |
5441 | continue; | |
5442 | ||
5443 | /* We don't lock the tree block, it's OK to be racy here */ | |
5444 | ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize, | |
5445 | &refs, &flags); | |
5446 | BUG_ON(ret); | |
5447 | BUG_ON(refs == 0); | |
5448 | ||
5449 | if (wc->stage == DROP_REFERENCE) { | |
5450 | if (refs == 1) | |
5451 | goto reada; | |
5452 | ||
5453 | if (wc->level == 1 && | |
5454 | (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) | |
5455 | continue; | |
5456 | if (!wc->update_ref || | |
5457 | generation <= root->root_key.offset) | |
5458 | continue; | |
5459 | btrfs_node_key_to_cpu(eb, &key, slot); | |
5460 | ret = btrfs_comp_cpu_keys(&key, | |
5461 | &wc->update_progress); | |
5462 | if (ret < 0) | |
5463 | continue; | |
5464 | } else { | |
5465 | if (wc->level == 1 && | |
5466 | (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) | |
5467 | continue; | |
5468 | } | |
5469 | reada: | |
5470 | ret = readahead_tree_block(root, bytenr, blocksize, | |
5471 | generation); | |
5472 | if (ret) | |
5473 | break; | |
5474 | last = bytenr + blocksize; | |
5475 | nread++; | |
5476 | } | |
5477 | wc->reada_slot = slot; | |
5478 | } | |
5479 | ||
5480 | /* | |
5481 | * hepler to process tree block while walking down the tree. | |
5482 | * | |
5483 | * when wc->stage == UPDATE_BACKREF, this function updates | |
5484 | * back refs for pointers in the block. | |
5485 | * | |
5486 | * NOTE: return value 1 means we should stop walking down. | |
5487 | */ | |
5488 | static noinline int walk_down_proc(struct btrfs_trans_handle *trans, | |
5489 | struct btrfs_root *root, | |
5490 | struct btrfs_path *path, | |
5491 | struct walk_control *wc, int lookup_info) | |
5492 | { | |
5493 | int level = wc->level; | |
5494 | struct extent_buffer *eb = path->nodes[level]; | |
5495 | u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF; | |
5496 | int ret; | |
5497 | ||
5498 | if (wc->stage == UPDATE_BACKREF && | |
5499 | btrfs_header_owner(eb) != root->root_key.objectid) | |
5500 | return 1; | |
5501 | ||
5502 | /* | |
5503 | * when reference count of tree block is 1, it won't increase | |
5504 | * again. once full backref flag is set, we never clear it. | |
5505 | */ | |
5506 | if (lookup_info && | |
5507 | ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) || | |
5508 | (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag)))) { | |
5509 | BUG_ON(!path->locks[level]); | |
5510 | ret = btrfs_lookup_extent_info(trans, root, | |
5511 | eb->start, eb->len, | |
5512 | &wc->refs[level], | |
5513 | &wc->flags[level]); | |
5514 | BUG_ON(ret); | |
5515 | BUG_ON(wc->refs[level] == 0); | |
5516 | } | |
5517 | ||
5518 | if (wc->stage == DROP_REFERENCE) { | |
5519 | if (wc->refs[level] > 1) | |
5520 | return 1; | |
5521 | ||
5522 | if (path->locks[level] && !wc->keep_locks) { | |
5523 | btrfs_tree_unlock(eb); | |
5524 | path->locks[level] = 0; | |
5525 | } | |
5526 | return 0; | |
5527 | } | |
5528 | ||
5529 | /* wc->stage == UPDATE_BACKREF */ | |
5530 | if (!(wc->flags[level] & flag)) { | |
5531 | BUG_ON(!path->locks[level]); | |
5532 | ret = btrfs_inc_ref(trans, root, eb, 1); | |
5533 | BUG_ON(ret); | |
5534 | ret = btrfs_dec_ref(trans, root, eb, 0); | |
5535 | BUG_ON(ret); | |
5536 | ret = btrfs_set_disk_extent_flags(trans, root, eb->start, | |
5537 | eb->len, flag, 0); | |
5538 | BUG_ON(ret); | |
5539 | wc->flags[level] |= flag; | |
5540 | } | |
5541 | ||
5542 | /* | |
5543 | * the block is shared by multiple trees, so it's not good to | |
5544 | * keep the tree lock | |
5545 | */ | |
5546 | if (path->locks[level] && level > 0) { | |
5547 | btrfs_tree_unlock(eb); | |
5548 | path->locks[level] = 0; | |
5549 | } | |
5550 | return 0; | |
5551 | } | |
5552 | ||
5553 | /* | |
5554 | * hepler to process tree block pointer. | |
5555 | * | |
5556 | * when wc->stage == DROP_REFERENCE, this function checks | |
5557 | * reference count of the block pointed to. if the block | |
5558 | * is shared and we need update back refs for the subtree | |
5559 | * rooted at the block, this function changes wc->stage to | |
5560 | * UPDATE_BACKREF. if the block is shared and there is no | |
5561 | * need to update back, this function drops the reference | |
5562 | * to the block. | |
5563 | * | |
5564 | * NOTE: return value 1 means we should stop walking down. | |
5565 | */ | |
5566 | static noinline int do_walk_down(struct btrfs_trans_handle *trans, | |
5567 | struct btrfs_root *root, | |
5568 | struct btrfs_path *path, | |
5569 | struct walk_control *wc, int *lookup_info) | |
5570 | { | |
5571 | u64 bytenr; | |
5572 | u64 generation; | |
5573 | u64 parent; | |
5574 | u32 blocksize; | |
5575 | struct btrfs_key key; | |
5576 | struct extent_buffer *next; | |
5577 | int level = wc->level; | |
5578 | int reada = 0; | |
5579 | int ret = 0; | |
5580 | ||
5581 | generation = btrfs_node_ptr_generation(path->nodes[level], | |
5582 | path->slots[level]); | |
5583 | /* | |
5584 | * if the lower level block was created before the snapshot | |
5585 | * was created, we know there is no need to update back refs | |
5586 | * for the subtree | |
5587 | */ | |
5588 | if (wc->stage == UPDATE_BACKREF && | |
5589 | generation <= root->root_key.offset) { | |
5590 | *lookup_info = 1; | |
5591 | return 1; | |
5592 | } | |
5593 | ||
5594 | bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]); | |
5595 | blocksize = btrfs_level_size(root, level - 1); | |
5596 | ||
5597 | next = btrfs_find_tree_block(root, bytenr, blocksize); | |
5598 | if (!next) { | |
5599 | next = btrfs_find_create_tree_block(root, bytenr, blocksize); | |
5600 | if (!next) | |
5601 | return -ENOMEM; | |
5602 | reada = 1; | |
5603 | } | |
5604 | btrfs_tree_lock(next); | |
5605 | btrfs_set_lock_blocking(next); | |
5606 | ||
5607 | ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize, | |
5608 | &wc->refs[level - 1], | |
5609 | &wc->flags[level - 1]); | |
5610 | BUG_ON(ret); | |
5611 | BUG_ON(wc->refs[level - 1] == 0); | |
5612 | *lookup_info = 0; | |
5613 | ||
5614 | if (wc->stage == DROP_REFERENCE) { | |
5615 | if (wc->refs[level - 1] > 1) { | |
5616 | if (level == 1 && | |
5617 | (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF)) | |
5618 | goto skip; | |
5619 | ||
5620 | if (!wc->update_ref || | |
5621 | generation <= root->root_key.offset) | |
5622 | goto skip; | |
5623 | ||
5624 | btrfs_node_key_to_cpu(path->nodes[level], &key, | |
5625 | path->slots[level]); | |
5626 | ret = btrfs_comp_cpu_keys(&key, &wc->update_progress); | |
5627 | if (ret < 0) | |
5628 | goto skip; | |
5629 | ||
5630 | wc->stage = UPDATE_BACKREF; | |
5631 | wc->shared_level = level - 1; | |
5632 | } | |
5633 | } else { | |
5634 | if (level == 1 && | |
5635 | (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF)) | |
5636 | goto skip; | |
5637 | } | |
5638 | ||
5639 | if (!btrfs_buffer_uptodate(next, generation)) { | |
5640 | btrfs_tree_unlock(next); | |
5641 | free_extent_buffer(next); | |
5642 | next = NULL; | |
5643 | *lookup_info = 1; | |
5644 | } | |
5645 | ||
5646 | if (!next) { | |
5647 | if (reada && level == 1) | |
5648 | reada_walk_down(trans, root, wc, path); | |
5649 | next = read_tree_block(root, bytenr, blocksize, generation); | |
5650 | btrfs_tree_lock(next); | |
5651 | btrfs_set_lock_blocking(next); | |
5652 | } | |
5653 | ||
5654 | level--; | |
5655 | BUG_ON(level != btrfs_header_level(next)); | |
5656 | path->nodes[level] = next; | |
5657 | path->slots[level] = 0; | |
5658 | path->locks[level] = 1; | |
5659 | wc->level = level; | |
5660 | if (wc->level == 1) | |
5661 | wc->reada_slot = 0; | |
5662 | return 0; | |
5663 | skip: | |
5664 | wc->refs[level - 1] = 0; | |
5665 | wc->flags[level - 1] = 0; | |
5666 | if (wc->stage == DROP_REFERENCE) { | |
5667 | if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) { | |
5668 | parent = path->nodes[level]->start; | |
5669 | } else { | |
5670 | BUG_ON(root->root_key.objectid != | |
5671 | btrfs_header_owner(path->nodes[level])); | |
5672 | parent = 0; | |
5673 | } | |
5674 | ||
5675 | ret = btrfs_free_extent(trans, root, bytenr, blocksize, parent, | |
5676 | root->root_key.objectid, level - 1, 0); | |
5677 | BUG_ON(ret); | |
5678 | } | |
5679 | btrfs_tree_unlock(next); | |
5680 | free_extent_buffer(next); | |
5681 | *lookup_info = 1; | |
5682 | return 1; | |
5683 | } | |
5684 | ||
5685 | /* | |
5686 | * hepler to process tree block while walking up the tree. | |
5687 | * | |
5688 | * when wc->stage == DROP_REFERENCE, this function drops | |
5689 | * reference count on the block. | |
5690 | * | |
5691 | * when wc->stage == UPDATE_BACKREF, this function changes | |
5692 | * wc->stage back to DROP_REFERENCE if we changed wc->stage | |
5693 | * to UPDATE_BACKREF previously while processing the block. | |
5694 | * | |
5695 | * NOTE: return value 1 means we should stop walking up. | |
5696 | */ | |
5697 | static noinline int walk_up_proc(struct btrfs_trans_handle *trans, | |
5698 | struct btrfs_root *root, | |
5699 | struct btrfs_path *path, | |
5700 | struct walk_control *wc) | |
5701 | { | |
5702 | int ret; | |
5703 | int level = wc->level; | |
5704 | struct extent_buffer *eb = path->nodes[level]; | |
5705 | u64 parent = 0; | |
5706 | ||
5707 | if (wc->stage == UPDATE_BACKREF) { | |
5708 | BUG_ON(wc->shared_level < level); | |
5709 | if (level < wc->shared_level) | |
5710 | goto out; | |
5711 | ||
5712 | ret = find_next_key(path, level + 1, &wc->update_progress); | |
5713 | if (ret > 0) | |
5714 | wc->update_ref = 0; | |
5715 | ||
5716 | wc->stage = DROP_REFERENCE; | |
5717 | wc->shared_level = -1; | |
5718 | path->slots[level] = 0; | |
5719 | ||
5720 | /* | |
5721 | * check reference count again if the block isn't locked. | |
5722 | * we should start walking down the tree again if reference | |
5723 | * count is one. | |
5724 | */ | |
5725 | if (!path->locks[level]) { | |
5726 | BUG_ON(level == 0); | |
5727 | btrfs_tree_lock(eb); | |
5728 | btrfs_set_lock_blocking(eb); | |
5729 | path->locks[level] = 1; | |
5730 | ||
5731 | ret = btrfs_lookup_extent_info(trans, root, | |
5732 | eb->start, eb->len, | |
5733 | &wc->refs[level], | |
5734 | &wc->flags[level]); | |
5735 | BUG_ON(ret); | |
5736 | BUG_ON(wc->refs[level] == 0); | |
5737 | if (wc->refs[level] == 1) { | |
5738 | btrfs_tree_unlock(eb); | |
5739 | path->locks[level] = 0; | |
5740 | return 1; | |
5741 | } | |
5742 | } | |
5743 | } | |
5744 | ||
5745 | /* wc->stage == DROP_REFERENCE */ | |
5746 | BUG_ON(wc->refs[level] > 1 && !path->locks[level]); | |
5747 | ||
5748 | if (wc->refs[level] == 1) { | |
5749 | if (level == 0) { | |
5750 | if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) | |
5751 | ret = btrfs_dec_ref(trans, root, eb, 1); | |
5752 | else | |
5753 | ret = btrfs_dec_ref(trans, root, eb, 0); | |
5754 | BUG_ON(ret); | |
5755 | } | |
5756 | /* make block locked assertion in clean_tree_block happy */ | |
5757 | if (!path->locks[level] && | |
5758 | btrfs_header_generation(eb) == trans->transid) { | |
5759 | btrfs_tree_lock(eb); | |
5760 | btrfs_set_lock_blocking(eb); | |
5761 | path->locks[level] = 1; | |
5762 | } | |
5763 | clean_tree_block(trans, root, eb); | |
5764 | } | |
5765 | ||
5766 | if (eb == root->node) { | |
5767 | if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) | |
5768 | parent = eb->start; | |
5769 | else | |
5770 | BUG_ON(root->root_key.objectid != | |
5771 | btrfs_header_owner(eb)); | |
5772 | } else { | |
5773 | if (wc->flags[level + 1] & BTRFS_BLOCK_FLAG_FULL_BACKREF) | |
5774 | parent = path->nodes[level + 1]->start; | |
5775 | else | |
5776 | BUG_ON(root->root_key.objectid != | |
5777 | btrfs_header_owner(path->nodes[level + 1])); | |
5778 | } | |
5779 | ||
5780 | btrfs_free_tree_block(trans, root, eb, parent, wc->refs[level] == 1); | |
5781 | out: | |
5782 | wc->refs[level] = 0; | |
5783 | wc->flags[level] = 0; | |
5784 | return 0; | |
5785 | } | |
5786 | ||
5787 | static noinline int walk_down_tree(struct btrfs_trans_handle *trans, | |
5788 | struct btrfs_root *root, | |
5789 | struct btrfs_path *path, | |
5790 | struct walk_control *wc) | |
5791 | { | |
5792 | int level = wc->level; | |
5793 | int lookup_info = 1; | |
5794 | int ret; | |
5795 | ||
5796 | while (level >= 0) { | |
5797 | ret = walk_down_proc(trans, root, path, wc, lookup_info); | |
5798 | if (ret > 0) | |
5799 | break; | |
5800 | ||
5801 | if (level == 0) | |
5802 | break; | |
5803 | ||
5804 | if (path->slots[level] >= | |
5805 | btrfs_header_nritems(path->nodes[level])) | |
5806 | break; | |
5807 | ||
5808 | ret = do_walk_down(trans, root, path, wc, &lookup_info); | |
5809 | if (ret > 0) { | |
5810 | path->slots[level]++; | |
5811 | continue; | |
5812 | } else if (ret < 0) | |
5813 | return ret; | |
5814 | level = wc->level; | |
5815 | } | |
5816 | return 0; | |
5817 | } | |
5818 | ||
5819 | static noinline int walk_up_tree(struct btrfs_trans_handle *trans, | |
5820 | struct btrfs_root *root, | |
5821 | struct btrfs_path *path, | |
5822 | struct walk_control *wc, int max_level) | |
5823 | { | |
5824 | int level = wc->level; | |
5825 | int ret; | |
5826 | ||
5827 | path->slots[level] = btrfs_header_nritems(path->nodes[level]); | |
5828 | while (level < max_level && path->nodes[level]) { | |
5829 | wc->level = level; | |
5830 | if (path->slots[level] + 1 < | |
5831 | btrfs_header_nritems(path->nodes[level])) { | |
5832 | path->slots[level]++; | |
5833 | return 0; | |
5834 | } else { | |
5835 | ret = walk_up_proc(trans, root, path, wc); | |
5836 | if (ret > 0) | |
5837 | return 0; | |
5838 | ||
5839 | if (path->locks[level]) { | |
5840 | btrfs_tree_unlock(path->nodes[level]); | |
5841 | path->locks[level] = 0; | |
5842 | } | |
5843 | free_extent_buffer(path->nodes[level]); | |
5844 | path->nodes[level] = NULL; | |
5845 | level++; | |
5846 | } | |
5847 | } | |
5848 | return 1; | |
5849 | } | |
5850 | ||
5851 | /* | |
5852 | * drop a subvolume tree. | |
5853 | * | |
5854 | * this function traverses the tree freeing any blocks that only | |
5855 | * referenced by the tree. | |
5856 | * | |
5857 | * when a shared tree block is found. this function decreases its | |
5858 | * reference count by one. if update_ref is true, this function | |
5859 | * also make sure backrefs for the shared block and all lower level | |
5860 | * blocks are properly updated. | |
5861 | */ | |
5862 | int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref) | |
5863 | { | |
5864 | struct btrfs_path *path; | |
5865 | struct btrfs_trans_handle *trans; | |
5866 | struct btrfs_root *tree_root = root->fs_info->tree_root; | |
5867 | struct btrfs_root_item *root_item = &root->root_item; | |
5868 | struct walk_control *wc; | |
5869 | struct btrfs_key key; | |
5870 | int err = 0; | |
5871 | int ret; | |
5872 | int level; | |
5873 | ||
5874 | path = btrfs_alloc_path(); | |
5875 | BUG_ON(!path); | |
5876 | ||
5877 | wc = kzalloc(sizeof(*wc), GFP_NOFS); | |
5878 | BUG_ON(!wc); | |
5879 | ||
5880 | trans = btrfs_start_transaction(tree_root, 0); | |
5881 | ||
5882 | if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) { | |
5883 | level = btrfs_header_level(root->node); | |
5884 | path->nodes[level] = btrfs_lock_root_node(root); | |
5885 | btrfs_set_lock_blocking(path->nodes[level]); | |
5886 | path->slots[level] = 0; | |
5887 | path->locks[level] = 1; | |
5888 | memset(&wc->update_progress, 0, | |
5889 | sizeof(wc->update_progress)); | |
5890 | } else { | |
5891 | btrfs_disk_key_to_cpu(&key, &root_item->drop_progress); | |
5892 | memcpy(&wc->update_progress, &key, | |
5893 | sizeof(wc->update_progress)); | |
5894 | ||
5895 | level = root_item->drop_level; | |
5896 | BUG_ON(level == 0); | |
5897 | path->lowest_level = level; | |
5898 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); | |
5899 | path->lowest_level = 0; | |
5900 | if (ret < 0) { | |
5901 | err = ret; | |
5902 | goto out; | |
5903 | } | |
5904 | WARN_ON(ret > 0); | |
5905 | ||
5906 | /* | |
5907 | * unlock our path, this is safe because only this | |
5908 | * function is allowed to delete this snapshot | |
5909 | */ | |
5910 | btrfs_unlock_up_safe(path, 0); | |
5911 | ||
5912 | level = btrfs_header_level(root->node); | |
5913 | while (1) { | |
5914 | btrfs_tree_lock(path->nodes[level]); | |
5915 | btrfs_set_lock_blocking(path->nodes[level]); | |
5916 | ||
5917 | ret = btrfs_lookup_extent_info(trans, root, | |
5918 | path->nodes[level]->start, | |
5919 | path->nodes[level]->len, | |
5920 | &wc->refs[level], | |
5921 | &wc->flags[level]); | |
5922 | BUG_ON(ret); | |
5923 | BUG_ON(wc->refs[level] == 0); | |
5924 | ||
5925 | if (level == root_item->drop_level) | |
5926 | break; | |
5927 | ||
5928 | btrfs_tree_unlock(path->nodes[level]); | |
5929 | WARN_ON(wc->refs[level] != 1); | |
5930 | level--; | |
5931 | } | |
5932 | } | |
5933 | ||
5934 | wc->level = level; | |
5935 | wc->shared_level = -1; | |
5936 | wc->stage = DROP_REFERENCE; | |
5937 | wc->update_ref = update_ref; | |
5938 | wc->keep_locks = 0; | |
5939 | wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root); | |
5940 | ||
5941 | while (1) { | |
5942 | ret = walk_down_tree(trans, root, path, wc); | |
5943 | if (ret < 0) { | |
5944 | err = ret; | |
5945 | break; | |
5946 | } | |
5947 | ||
5948 | ret = walk_up_tree(trans, root, path, wc, BTRFS_MAX_LEVEL); | |
5949 | if (ret < 0) { | |
5950 | err = ret; | |
5951 | break; | |
5952 | } | |
5953 | ||
5954 | if (ret > 0) { | |
5955 | BUG_ON(wc->stage != DROP_REFERENCE); | |
5956 | break; | |
5957 | } | |
5958 | ||
5959 | if (wc->stage == DROP_REFERENCE) { | |
5960 | level = wc->level; | |
5961 | btrfs_node_key(path->nodes[level], | |
5962 | &root_item->drop_progress, | |
5963 | path->slots[level]); | |
5964 | root_item->drop_level = level; | |
5965 | } | |
5966 | ||
5967 | BUG_ON(wc->level == 0); | |
5968 | if (trans->transaction->in_commit || | |
5969 | trans->transaction->delayed_refs.flushing) { | |
5970 | ret = btrfs_update_root(trans, tree_root, | |
5971 | &root->root_key, | |
5972 | root_item); | |
5973 | BUG_ON(ret); | |
5974 | ||
5975 | btrfs_end_transaction(trans, tree_root); | |
5976 | trans = btrfs_start_transaction(tree_root, 0); | |
5977 | if (IS_ERR(trans)) | |
5978 | return PTR_ERR(trans); | |
5979 | } else { | |
5980 | unsigned long update; | |
5981 | update = trans->delayed_ref_updates; | |
5982 | trans->delayed_ref_updates = 0; | |
5983 | if (update) | |
5984 | btrfs_run_delayed_refs(trans, tree_root, | |
5985 | update); | |
5986 | } | |
5987 | } | |
5988 | btrfs_release_path(root, path); | |
5989 | BUG_ON(err); | |
5990 | ||
5991 | ret = btrfs_del_root(trans, tree_root, &root->root_key); | |
5992 | BUG_ON(ret); | |
5993 | ||
5994 | if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) { | |
5995 | ret = btrfs_find_last_root(tree_root, root->root_key.objectid, | |
5996 | NULL, NULL); | |
5997 | BUG_ON(ret < 0); | |
5998 | if (ret > 0) { | |
5999 | ret = btrfs_del_orphan_item(trans, tree_root, | |
6000 | root->root_key.objectid); | |
6001 | BUG_ON(ret); | |
6002 | } | |
6003 | } | |
6004 | ||
6005 | if (root->in_radix) { | |
6006 | btrfs_free_fs_root(tree_root->fs_info, root); | |
6007 | } else { | |
6008 | free_extent_buffer(root->node); | |
6009 | free_extent_buffer(root->commit_root); | |
6010 | kfree(root); | |
6011 | } | |
6012 | out: | |
6013 | btrfs_end_transaction(trans, tree_root); | |
6014 | kfree(wc); | |
6015 | btrfs_free_path(path); | |
6016 | return err; | |
6017 | } | |
6018 | ||
6019 | /* | |
6020 | * drop subtree rooted at tree block 'node'. | |
6021 | * | |
6022 | * NOTE: this function will unlock and release tree block 'node' | |
6023 | */ | |
6024 | int btrfs_drop_subtree(struct btrfs_trans_handle *trans, | |
6025 | struct btrfs_root *root, | |
6026 | struct extent_buffer *node, | |
6027 | struct extent_buffer *parent) | |
6028 | { | |
6029 | struct btrfs_path *path; | |
6030 | struct walk_control *wc; | |
6031 | int level; | |
6032 | int parent_level; | |
6033 | int ret = 0; | |
6034 | int wret; | |
6035 | ||
6036 | BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID); | |
6037 | ||
6038 | path = btrfs_alloc_path(); | |
6039 | BUG_ON(!path); | |
6040 | ||
6041 | wc = kzalloc(sizeof(*wc), GFP_NOFS); | |
6042 | BUG_ON(!wc); | |
6043 | ||
6044 | btrfs_assert_tree_locked(parent); | |
6045 | parent_level = btrfs_header_level(parent); | |
6046 | extent_buffer_get(parent); | |
6047 | path->nodes[parent_level] = parent; | |
6048 | path->slots[parent_level] = btrfs_header_nritems(parent); | |
6049 | ||
6050 | btrfs_assert_tree_locked(node); | |
6051 | level = btrfs_header_level(node); | |
6052 | path->nodes[level] = node; | |
6053 | path->slots[level] = 0; | |
6054 | path->locks[level] = 1; | |
6055 | ||
6056 | wc->refs[parent_level] = 1; | |
6057 | wc->flags[parent_level] = BTRFS_BLOCK_FLAG_FULL_BACKREF; | |
6058 | wc->level = level; | |
6059 | wc->shared_level = -1; | |
6060 | wc->stage = DROP_REFERENCE; | |
6061 | wc->update_ref = 0; | |
6062 | wc->keep_locks = 1; | |
6063 | wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root); | |
6064 | ||
6065 | while (1) { | |
6066 | wret = walk_down_tree(trans, root, path, wc); | |
6067 | if (wret < 0) { | |
6068 | ret = wret; | |
6069 | break; | |
6070 | } | |
6071 | ||
6072 | wret = walk_up_tree(trans, root, path, wc, parent_level); | |
6073 | if (wret < 0) | |
6074 | ret = wret; | |
6075 | if (wret != 0) | |
6076 | break; | |
6077 | } | |
6078 | ||
6079 | kfree(wc); | |
6080 | btrfs_free_path(path); | |
6081 | return ret; | |
6082 | } | |
6083 | ||
6084 | #if 0 | |
6085 | static unsigned long calc_ra(unsigned long start, unsigned long last, | |
6086 | unsigned long nr) | |
6087 | { | |
6088 | return min(last, start + nr - 1); | |
6089 | } | |
6090 | ||
6091 | static noinline int relocate_inode_pages(struct inode *inode, u64 start, | |
6092 | u64 len) | |
6093 | { | |
6094 | u64 page_start; | |
6095 | u64 page_end; | |
6096 | unsigned long first_index; | |
6097 | unsigned long last_index; | |
6098 | unsigned long i; | |
6099 | struct page *page; | |
6100 | struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; | |
6101 | struct file_ra_state *ra; | |
6102 | struct btrfs_ordered_extent *ordered; | |
6103 | unsigned int total_read = 0; | |
6104 | unsigned int total_dirty = 0; | |
6105 | int ret = 0; | |
6106 | ||
6107 | ra = kzalloc(sizeof(*ra), GFP_NOFS); | |
6108 | ||
6109 | mutex_lock(&inode->i_mutex); | |
6110 | first_index = start >> PAGE_CACHE_SHIFT; | |
6111 | last_index = (start + len - 1) >> PAGE_CACHE_SHIFT; | |
6112 | ||
6113 | /* make sure the dirty trick played by the caller work */ | |
6114 | ret = invalidate_inode_pages2_range(inode->i_mapping, | |
6115 | first_index, last_index); | |
6116 | if (ret) | |
6117 | goto out_unlock; | |
6118 | ||
6119 | file_ra_state_init(ra, inode->i_mapping); | |
6120 | ||
6121 | for (i = first_index ; i <= last_index; i++) { | |
6122 | if (total_read % ra->ra_pages == 0) { | |
6123 | btrfs_force_ra(inode->i_mapping, ra, NULL, i, | |
6124 | calc_ra(i, last_index, ra->ra_pages)); | |
6125 | } | |
6126 | total_read++; | |
6127 | again: | |
6128 | if (((u64)i << PAGE_CACHE_SHIFT) > i_size_read(inode)) | |
6129 | BUG_ON(1); | |
6130 | page = grab_cache_page(inode->i_mapping, i); | |
6131 | if (!page) { | |
6132 | ret = -ENOMEM; | |
6133 | goto out_unlock; | |
6134 | } | |
6135 | if (!PageUptodate(page)) { | |
6136 | btrfs_readpage(NULL, page); | |
6137 | lock_page(page); | |
6138 | if (!PageUptodate(page)) { | |
6139 | unlock_page(page); | |
6140 | page_cache_release(page); | |
6141 | ret = -EIO; | |
6142 | goto out_unlock; | |
6143 | } | |
6144 | } | |
6145 | wait_on_page_writeback(page); | |
6146 | ||
6147 | page_start = (u64)page->index << PAGE_CACHE_SHIFT; | |
6148 | page_end = page_start + PAGE_CACHE_SIZE - 1; | |
6149 | lock_extent(io_tree, page_start, page_end, GFP_NOFS); | |
6150 | ||
6151 | ordered = btrfs_lookup_ordered_extent(inode, page_start); | |
6152 | if (ordered) { | |
6153 | unlock_extent(io_tree, page_start, page_end, GFP_NOFS); | |
6154 | unlock_page(page); | |
6155 | page_cache_release(page); | |
6156 | btrfs_start_ordered_extent(inode, ordered, 1); | |
6157 | btrfs_put_ordered_extent(ordered); | |
6158 | goto again; | |
6159 | } | |
6160 | set_page_extent_mapped(page); | |
6161 | ||
6162 | if (i == first_index) | |
6163 | set_extent_bits(io_tree, page_start, page_end, | |
6164 | EXTENT_BOUNDARY, GFP_NOFS); | |
6165 | btrfs_set_extent_delalloc(inode, page_start, page_end); | |
6166 | ||
6167 | set_page_dirty(page); | |
6168 | total_dirty++; | |
6169 | ||
6170 | unlock_extent(io_tree, page_start, page_end, GFP_NOFS); | |
6171 | unlock_page(page); | |
6172 | page_cache_release(page); | |
6173 | } | |
6174 | ||
6175 | out_unlock: | |
6176 | kfree(ra); | |
6177 | mutex_unlock(&inode->i_mutex); | |
6178 | balance_dirty_pages_ratelimited_nr(inode->i_mapping, total_dirty); | |
6179 | return ret; | |
6180 | } | |
6181 | ||
6182 | static noinline int relocate_data_extent(struct inode *reloc_inode, | |
6183 | struct btrfs_key *extent_key, | |
6184 | u64 offset) | |
6185 | { | |
6186 | struct btrfs_root *root = BTRFS_I(reloc_inode)->root; | |
6187 | struct extent_map_tree *em_tree = &BTRFS_I(reloc_inode)->extent_tree; | |
6188 | struct extent_map *em; | |
6189 | u64 start = extent_key->objectid - offset; | |
6190 | u64 end = start + extent_key->offset - 1; | |
6191 | ||
6192 | em = alloc_extent_map(GFP_NOFS); | |
6193 | BUG_ON(!em || IS_ERR(em)); | |
6194 | ||
6195 | em->start = start; | |
6196 | em->len = extent_key->offset; | |
6197 | em->block_len = extent_key->offset; | |
6198 | em->block_start = extent_key->objectid; | |
6199 | em->bdev = root->fs_info->fs_devices->latest_bdev; | |
6200 | set_bit(EXTENT_FLAG_PINNED, &em->flags); | |
6201 | ||
6202 | /* setup extent map to cheat btrfs_readpage */ | |
6203 | lock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS); | |
6204 | while (1) { | |
6205 | int ret; | |
6206 | write_lock(&em_tree->lock); | |
6207 | ret = add_extent_mapping(em_tree, em); | |
6208 | write_unlock(&em_tree->lock); | |
6209 | if (ret != -EEXIST) { | |
6210 | free_extent_map(em); | |
6211 | break; | |
6212 | } | |
6213 | btrfs_drop_extent_cache(reloc_inode, start, end, 0); | |
6214 | } | |
6215 | unlock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS); | |
6216 | ||
6217 | return relocate_inode_pages(reloc_inode, start, extent_key->offset); | |
6218 | } | |
6219 | ||
6220 | struct btrfs_ref_path { | |
6221 | u64 extent_start; | |
6222 | u64 nodes[BTRFS_MAX_LEVEL]; | |
6223 | u64 root_objectid; | |
6224 | u64 root_generation; | |
6225 | u64 owner_objectid; | |
6226 | u32 num_refs; | |
6227 | int lowest_level; | |
6228 | int current_level; | |
6229 | int shared_level; | |
6230 | ||
6231 | struct btrfs_key node_keys[BTRFS_MAX_LEVEL]; | |
6232 | u64 new_nodes[BTRFS_MAX_LEVEL]; | |
6233 | }; | |
6234 | ||
6235 | struct disk_extent { | |
6236 | u64 ram_bytes; | |
6237 | u64 disk_bytenr; | |
6238 | u64 disk_num_bytes; | |
6239 | u64 offset; | |
6240 | u64 num_bytes; | |
6241 | u8 compression; | |
6242 | u8 encryption; | |
6243 | u16 other_encoding; | |
6244 | }; | |
6245 | ||
6246 | static int is_cowonly_root(u64 root_objectid) | |
6247 | { | |
6248 | if (root_objectid == BTRFS_ROOT_TREE_OBJECTID || | |
6249 | root_objectid == BTRFS_EXTENT_TREE_OBJECTID || | |
6250 | root_objectid == BTRFS_CHUNK_TREE_OBJECTID || | |
6251 | root_objectid == BTRFS_DEV_TREE_OBJECTID || | |
6252 | root_objectid == BTRFS_TREE_LOG_OBJECTID || | |
6253 | root_objectid == BTRFS_CSUM_TREE_OBJECTID) | |
6254 | return 1; | |
6255 | return 0; | |
6256 | } | |
6257 | ||
6258 | static noinline int __next_ref_path(struct btrfs_trans_handle *trans, | |
6259 | struct btrfs_root *extent_root, | |
6260 | struct btrfs_ref_path *ref_path, | |
6261 | int first_time) | |
6262 | { | |
6263 | struct extent_buffer *leaf; | |
6264 | struct btrfs_path *path; | |
6265 | struct btrfs_extent_ref *ref; | |
6266 | struct btrfs_key key; | |
6267 | struct btrfs_key found_key; | |
6268 | u64 bytenr; | |
6269 | u32 nritems; | |
6270 | int level; | |
6271 | int ret = 1; | |
6272 | ||
6273 | path = btrfs_alloc_path(); | |
6274 | if (!path) | |
6275 | return -ENOMEM; | |
6276 | ||
6277 | if (first_time) { | |
6278 | ref_path->lowest_level = -1; | |
6279 | ref_path->current_level = -1; | |
6280 | ref_path->shared_level = -1; | |
6281 | goto walk_up; | |
6282 | } | |
6283 | walk_down: | |
6284 | level = ref_path->current_level - 1; | |
6285 | while (level >= -1) { | |
6286 | u64 parent; | |
6287 | if (level < ref_path->lowest_level) | |
6288 | break; | |
6289 | ||
6290 | if (level >= 0) | |
6291 | bytenr = ref_path->nodes[level]; | |
6292 | else | |
6293 | bytenr = ref_path->extent_start; | |
6294 | BUG_ON(bytenr == 0); | |
6295 | ||
6296 | parent = ref_path->nodes[level + 1]; | |
6297 | ref_path->nodes[level + 1] = 0; | |
6298 | ref_path->current_level = level; | |
6299 | BUG_ON(parent == 0); | |
6300 | ||
6301 | key.objectid = bytenr; | |
6302 | key.offset = parent + 1; | |
6303 | key.type = BTRFS_EXTENT_REF_KEY; | |
6304 | ||
6305 | ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0); | |
6306 | if (ret < 0) | |
6307 | goto out; | |
6308 | BUG_ON(ret == 0); | |
6309 | ||
6310 | leaf = path->nodes[0]; | |
6311 | nritems = btrfs_header_nritems(leaf); | |
6312 | if (path->slots[0] >= nritems) { | |
6313 | ret = btrfs_next_leaf(extent_root, path); | |
6314 | if (ret < 0) | |
6315 | goto out; | |
6316 | if (ret > 0) | |
6317 | goto next; | |
6318 | leaf = path->nodes[0]; | |
6319 | } | |
6320 | ||
6321 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); | |
6322 | if (found_key.objectid == bytenr && | |
6323 | found_key.type == BTRFS_EXTENT_REF_KEY) { | |
6324 | if (level < ref_path->shared_level) | |
6325 | ref_path->shared_level = level; | |
6326 | goto found; | |
6327 | } | |
6328 | next: | |
6329 | level--; | |
6330 | btrfs_release_path(extent_root, path); | |
6331 | cond_resched(); | |
6332 | } | |
6333 | /* reached lowest level */ | |
6334 | ret = 1; | |
6335 | goto out; | |
6336 | walk_up: | |
6337 | level = ref_path->current_level; | |
6338 | while (level < BTRFS_MAX_LEVEL - 1) { | |
6339 | u64 ref_objectid; | |
6340 | ||
6341 | if (level >= 0) | |
6342 | bytenr = ref_path->nodes[level]; | |
6343 | else | |
6344 | bytenr = ref_path->extent_start; | |
6345 | ||
6346 | BUG_ON(bytenr == 0); | |
6347 | ||
6348 | key.objectid = bytenr; | |
6349 | key.offset = 0; | |
6350 | key.type = BTRFS_EXTENT_REF_KEY; | |
6351 | ||
6352 | ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0); | |
6353 | if (ret < 0) | |
6354 | goto out; | |
6355 | ||
6356 | leaf = path->nodes[0]; | |
6357 | nritems = btrfs_header_nritems(leaf); | |
6358 | if (path->slots[0] >= nritems) { | |
6359 | ret = btrfs_next_leaf(extent_root, path); | |
6360 | if (ret < 0) | |
6361 | goto out; | |
6362 | if (ret > 0) { | |
6363 | /* the extent was freed by someone */ | |
6364 | if (ref_path->lowest_level == level) | |
6365 | goto out; | |
6366 | btrfs_release_path(extent_root, path); | |
6367 | goto walk_down; | |
6368 | } | |
6369 | leaf = path->nodes[0]; | |
6370 | } | |
6371 | ||
6372 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); | |
6373 | if (found_key.objectid != bytenr || | |
6374 | found_key.type != BTRFS_EXTENT_REF_KEY) { | |
6375 | /* the extent was freed by someone */ | |
6376 | if (ref_path->lowest_level == level) { | |
6377 | ret = 1; | |
6378 | goto out; | |
6379 | } | |
6380 | btrfs_release_path(extent_root, path); | |
6381 | goto walk_down; | |
6382 | } | |
6383 | found: | |
6384 | ref = btrfs_item_ptr(leaf, path->slots[0], | |
6385 | struct btrfs_extent_ref); | |
6386 | ref_objectid = btrfs_ref_objectid(leaf, ref); | |
6387 | if (ref_objectid < BTRFS_FIRST_FREE_OBJECTID) { | |
6388 | if (first_time) { | |
6389 | level = (int)ref_objectid; | |
6390 | BUG_ON(level >= BTRFS_MAX_LEVEL); | |
6391 | ref_path->lowest_level = level; | |
6392 | ref_path->current_level = level; | |
6393 | ref_path->nodes[level] = bytenr; | |
6394 | } else { | |
6395 | WARN_ON(ref_objectid != level); | |
6396 | } | |
6397 | } else { | |
6398 | WARN_ON(level != -1); | |
6399 | } | |
6400 | first_time = 0; | |
6401 | ||
6402 | if (ref_path->lowest_level == level) { | |
6403 | ref_path->owner_objectid = ref_objectid; | |
6404 | ref_path->num_refs = btrfs_ref_num_refs(leaf, ref); | |
6405 | } | |
6406 | ||
6407 | /* | |
6408 | * the block is tree root or the block isn't in reference | |
6409 | * counted tree. | |
6410 | */ | |
6411 | if (found_key.objectid == found_key.offset || | |
6412 | is_cowonly_root(btrfs_ref_root(leaf, ref))) { | |
6413 | ref_path->root_objectid = btrfs_ref_root(leaf, ref); | |
6414 | ref_path->root_generation = | |
6415 | btrfs_ref_generation(leaf, ref); | |
6416 | if (level < 0) { | |
6417 | /* special reference from the tree log */ | |
6418 | ref_path->nodes[0] = found_key.offset; | |
6419 | ref_path->current_level = 0; | |
6420 | } | |
6421 | ret = 0; | |
6422 | goto out; | |
6423 | } | |
6424 | ||
6425 | level++; | |
6426 | BUG_ON(ref_path->nodes[level] != 0); | |
6427 | ref_path->nodes[level] = found_key.offset; | |
6428 | ref_path->current_level = level; | |
6429 | ||
6430 | /* | |
6431 | * the reference was created in the running transaction, | |
6432 | * no need to continue walking up. | |
6433 | */ | |
6434 | if (btrfs_ref_generation(leaf, ref) == trans->transid) { | |
6435 | ref_path->root_objectid = btrfs_ref_root(leaf, ref); | |
6436 | ref_path->root_generation = | |
6437 | btrfs_ref_generation(leaf, ref); | |
6438 | ret = 0; | |
6439 | goto out; | |
6440 | } | |
6441 | ||
6442 | btrfs_release_path(extent_root, path); | |
6443 | cond_resched(); | |
6444 | } | |
6445 | /* reached max tree level, but no tree root found. */ | |
6446 | BUG(); | |
6447 | out: | |
6448 | btrfs_free_path(path); | |
6449 | return ret; | |
6450 | } | |
6451 | ||
6452 | static int btrfs_first_ref_path(struct btrfs_trans_handle *trans, | |
6453 | struct btrfs_root *extent_root, | |
6454 | struct btrfs_ref_path *ref_path, | |
6455 | u64 extent_start) | |
6456 | { | |
6457 | memset(ref_path, 0, sizeof(*ref_path)); | |
6458 | ref_path->extent_start = extent_start; | |
6459 | ||
6460 | return __next_ref_path(trans, extent_root, ref_path, 1); | |
6461 | } | |
6462 | ||
6463 | static int btrfs_next_ref_path(struct btrfs_trans_handle *trans, | |
6464 | struct btrfs_root *extent_root, | |
6465 | struct btrfs_ref_path *ref_path) | |
6466 | { | |
6467 | return __next_ref_path(trans, extent_root, ref_path, 0); | |
6468 | } | |
6469 | ||
6470 | static noinline int get_new_locations(struct inode *reloc_inode, | |
6471 | struct btrfs_key *extent_key, | |
6472 | u64 offset, int no_fragment, | |
6473 | struct disk_extent **extents, | |
6474 | int *nr_extents) | |
6475 | { | |
6476 | struct btrfs_root *root = BTRFS_I(reloc_inode)->root; | |
6477 | struct btrfs_path *path; | |
6478 | struct btrfs_file_extent_item *fi; | |
6479 | struct extent_buffer *leaf; | |
6480 | struct disk_extent *exts = *extents; | |
6481 | struct btrfs_key found_key; | |
6482 | u64 cur_pos; | |
6483 | u64 last_byte; | |
6484 | u32 nritems; | |
6485 | int nr = 0; | |
6486 | int max = *nr_extents; | |
6487 | int ret; | |
6488 | ||
6489 | WARN_ON(!no_fragment && *extents); | |
6490 | if (!exts) { | |
6491 | max = 1; | |
6492 | exts = kmalloc(sizeof(*exts) * max, GFP_NOFS); | |
6493 | if (!exts) | |
6494 | return -ENOMEM; | |
6495 | } | |
6496 | ||
6497 | path = btrfs_alloc_path(); | |
6498 | BUG_ON(!path); | |
6499 | ||
6500 | cur_pos = extent_key->objectid - offset; | |
6501 | last_byte = extent_key->objectid + extent_key->offset; | |
6502 | ret = btrfs_lookup_file_extent(NULL, root, path, reloc_inode->i_ino, | |
6503 | cur_pos, 0); | |
6504 | if (ret < 0) | |
6505 | goto out; | |
6506 | if (ret > 0) { | |
6507 | ret = -ENOENT; | |
6508 | goto out; | |
6509 | } | |
6510 | ||
6511 | while (1) { | |
6512 | leaf = path->nodes[0]; | |
6513 | nritems = btrfs_header_nritems(leaf); | |
6514 | if (path->slots[0] >= nritems) { | |
6515 | ret = btrfs_next_leaf(root, path); | |
6516 | if (ret < 0) | |
6517 | goto out; | |
6518 | if (ret > 0) | |
6519 | break; | |
6520 | leaf = path->nodes[0]; | |
6521 | } | |
6522 | ||
6523 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); | |
6524 | if (found_key.offset != cur_pos || | |
6525 | found_key.type != BTRFS_EXTENT_DATA_KEY || | |
6526 | found_key.objectid != reloc_inode->i_ino) | |
6527 | break; | |
6528 | ||
6529 | fi = btrfs_item_ptr(leaf, path->slots[0], | |
6530 | struct btrfs_file_extent_item); | |
6531 | if (btrfs_file_extent_type(leaf, fi) != | |
6532 | BTRFS_FILE_EXTENT_REG || | |
6533 | btrfs_file_extent_disk_bytenr(leaf, fi) == 0) | |
6534 | break; | |
6535 | ||
6536 | if (nr == max) { | |
6537 | struct disk_extent *old = exts; | |
6538 | max *= 2; | |
6539 | exts = kzalloc(sizeof(*exts) * max, GFP_NOFS); | |
6540 | memcpy(exts, old, sizeof(*exts) * nr); | |
6541 | if (old != *extents) | |
6542 | kfree(old); | |
6543 | } | |
6544 | ||
6545 | exts[nr].disk_bytenr = | |
6546 | btrfs_file_extent_disk_bytenr(leaf, fi); | |
6547 | exts[nr].disk_num_bytes = | |
6548 | btrfs_file_extent_disk_num_bytes(leaf, fi); | |
6549 | exts[nr].offset = btrfs_file_extent_offset(leaf, fi); | |
6550 | exts[nr].num_bytes = btrfs_file_extent_num_bytes(leaf, fi); | |
6551 | exts[nr].ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi); | |
6552 | exts[nr].compression = btrfs_file_extent_compression(leaf, fi); | |
6553 | exts[nr].encryption = btrfs_file_extent_encryption(leaf, fi); | |
6554 | exts[nr].other_encoding = btrfs_file_extent_other_encoding(leaf, | |
6555 | fi); | |
6556 | BUG_ON(exts[nr].offset > 0); | |
6557 | BUG_ON(exts[nr].compression || exts[nr].encryption); | |
6558 | BUG_ON(exts[nr].num_bytes != exts[nr].disk_num_bytes); | |
6559 | ||
6560 | cur_pos += exts[nr].num_bytes; | |
6561 | nr++; | |
6562 | ||
6563 | if (cur_pos + offset >= last_byte) | |
6564 | break; | |
6565 | ||
6566 | if (no_fragment) { | |
6567 | ret = 1; | |
6568 | goto out; | |
6569 | } | |
6570 | path->slots[0]++; | |
6571 | } | |
6572 | ||
6573 | BUG_ON(cur_pos + offset > last_byte); | |
6574 | if (cur_pos + offset < last_byte) { | |
6575 | ret = -ENOENT; | |
6576 | goto out; | |
6577 | } | |
6578 | ret = 0; | |
6579 | out: | |
6580 | btrfs_free_path(path); | |
6581 | if (ret) { | |
6582 | if (exts != *extents) | |
6583 | kfree(exts); | |
6584 | } else { | |
6585 | *extents = exts; | |
6586 | *nr_extents = nr; | |
6587 | } | |
6588 | return ret; | |
6589 | } | |
6590 | ||
6591 | static noinline int replace_one_extent(struct btrfs_trans_handle *trans, | |
6592 | struct btrfs_root *root, | |
6593 | struct btrfs_path *path, | |
6594 | struct btrfs_key *extent_key, | |
6595 | struct btrfs_key *leaf_key, | |
6596 | struct btrfs_ref_path *ref_path, | |
6597 | struct disk_extent *new_extents, | |
6598 | int nr_extents) | |
6599 | { | |
6600 | struct extent_buffer *leaf; | |
6601 | struct btrfs_file_extent_item *fi; | |
6602 | struct inode *inode = NULL; | |
6603 | struct btrfs_key key; | |
6604 | u64 lock_start = 0; | |
6605 | u64 lock_end = 0; | |
6606 | u64 num_bytes; | |
6607 | u64 ext_offset; | |
6608 | u64 search_end = (u64)-1; | |
6609 | u32 nritems; | |
6610 | int nr_scaned = 0; | |
6611 | int extent_locked = 0; | |
6612 | int extent_type; | |
6613 | int ret; | |
6614 | ||
6615 | memcpy(&key, leaf_key, sizeof(key)); | |
6616 | if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) { | |
6617 | if (key.objectid < ref_path->owner_objectid || | |
6618 | (key.objectid == ref_path->owner_objectid && | |
6619 | key.type < BTRFS_EXTENT_DATA_KEY)) { | |
6620 | key.objectid = ref_path->owner_objectid; | |
6621 | key.type = BTRFS_EXTENT_DATA_KEY; | |
6622 | key.offset = 0; | |
6623 | } | |
6624 | } | |
6625 | ||
6626 | while (1) { | |
6627 | ret = btrfs_search_slot(trans, root, &key, path, 0, 1); | |
6628 | if (ret < 0) | |
6629 | goto out; | |
6630 | ||
6631 | leaf = path->nodes[0]; | |
6632 | nritems = btrfs_header_nritems(leaf); | |
6633 | next: | |
6634 | if (extent_locked && ret > 0) { | |
6635 | /* | |
6636 | * the file extent item was modified by someone | |
6637 | * before the extent got locked. | |
6638 | */ | |
6639 | unlock_extent(&BTRFS_I(inode)->io_tree, lock_start, | |
6640 | lock_end, GFP_NOFS); | |
6641 | extent_locked = 0; | |
6642 | } | |
6643 | ||
6644 | if (path->slots[0] >= nritems) { | |
6645 | if (++nr_scaned > 2) | |
6646 | break; | |
6647 | ||
6648 | BUG_ON(extent_locked); | |
6649 | ret = btrfs_next_leaf(root, path); | |
6650 | if (ret < 0) | |
6651 | goto out; | |
6652 | if (ret > 0) | |
6653 | break; | |
6654 | leaf = path->nodes[0]; | |
6655 | nritems = btrfs_header_nritems(leaf); | |
6656 | } | |
6657 | ||
6658 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
6659 | ||
6660 | if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) { | |
6661 | if ((key.objectid > ref_path->owner_objectid) || | |
6662 | (key.objectid == ref_path->owner_objectid && | |
6663 | key.type > BTRFS_EXTENT_DATA_KEY) || | |
6664 | key.offset >= search_end) | |
6665 | break; | |
6666 | } | |
6667 | ||
6668 | if (inode && key.objectid != inode->i_ino) { | |
6669 | BUG_ON(extent_locked); | |
6670 | btrfs_release_path(root, path); | |
6671 | mutex_unlock(&inode->i_mutex); | |
6672 | iput(inode); | |
6673 | inode = NULL; | |
6674 | continue; | |
6675 | } | |
6676 | ||
6677 | if (key.type != BTRFS_EXTENT_DATA_KEY) { | |
6678 | path->slots[0]++; | |
6679 | ret = 1; | |
6680 | goto next; | |
6681 | } | |
6682 | fi = btrfs_item_ptr(leaf, path->slots[0], | |
6683 | struct btrfs_file_extent_item); | |
6684 | extent_type = btrfs_file_extent_type(leaf, fi); | |
6685 | if ((extent_type != BTRFS_FILE_EXTENT_REG && | |
6686 | extent_type != BTRFS_FILE_EXTENT_PREALLOC) || | |
6687 | (btrfs_file_extent_disk_bytenr(leaf, fi) != | |
6688 | extent_key->objectid)) { | |
6689 | path->slots[0]++; | |
6690 | ret = 1; | |
6691 | goto next; | |
6692 | } | |
6693 | ||
6694 | num_bytes = btrfs_file_extent_num_bytes(leaf, fi); | |
6695 | ext_offset = btrfs_file_extent_offset(leaf, fi); | |
6696 | ||
6697 | if (search_end == (u64)-1) { | |
6698 | search_end = key.offset - ext_offset + | |
6699 | btrfs_file_extent_ram_bytes(leaf, fi); | |
6700 | } | |
6701 | ||
6702 | if (!extent_locked) { | |
6703 | lock_start = key.offset; | |
6704 | lock_end = lock_start + num_bytes - 1; | |
6705 | } else { | |
6706 | if (lock_start > key.offset || | |
6707 | lock_end + 1 < key.offset + num_bytes) { | |
6708 | unlock_extent(&BTRFS_I(inode)->io_tree, | |
6709 | lock_start, lock_end, GFP_NOFS); | |
6710 | extent_locked = 0; | |
6711 | } | |
6712 | } | |
6713 | ||
6714 | if (!inode) { | |
6715 | btrfs_release_path(root, path); | |
6716 | ||
6717 | inode = btrfs_iget_locked(root->fs_info->sb, | |
6718 | key.objectid, root); | |
6719 | if (inode->i_state & I_NEW) { | |
6720 | BTRFS_I(inode)->root = root; | |
6721 | BTRFS_I(inode)->location.objectid = | |
6722 | key.objectid; | |
6723 | BTRFS_I(inode)->location.type = | |
6724 | BTRFS_INODE_ITEM_KEY; | |
6725 | BTRFS_I(inode)->location.offset = 0; | |
6726 | btrfs_read_locked_inode(inode); | |
6727 | unlock_new_inode(inode); | |
6728 | } | |
6729 | /* | |
6730 | * some code call btrfs_commit_transaction while | |
6731 | * holding the i_mutex, so we can't use mutex_lock | |
6732 | * here. | |
6733 | */ | |
6734 | if (is_bad_inode(inode) || | |
6735 | !mutex_trylock(&inode->i_mutex)) { | |
6736 | iput(inode); | |
6737 | inode = NULL; | |
6738 | key.offset = (u64)-1; | |
6739 | goto skip; | |
6740 | } | |
6741 | } | |
6742 | ||
6743 | if (!extent_locked) { | |
6744 | struct btrfs_ordered_extent *ordered; | |
6745 | ||
6746 | btrfs_release_path(root, path); | |
6747 | ||
6748 | lock_extent(&BTRFS_I(inode)->io_tree, lock_start, | |
6749 | lock_end, GFP_NOFS); | |
6750 | ordered = btrfs_lookup_first_ordered_extent(inode, | |
6751 | lock_end); | |
6752 | if (ordered && | |
6753 | ordered->file_offset <= lock_end && | |
6754 | ordered->file_offset + ordered->len > lock_start) { | |
6755 | unlock_extent(&BTRFS_I(inode)->io_tree, | |
6756 | lock_start, lock_end, GFP_NOFS); | |
6757 | btrfs_start_ordered_extent(inode, ordered, 1); | |
6758 | btrfs_put_ordered_extent(ordered); | |
6759 | key.offset += num_bytes; | |
6760 | goto skip; | |
6761 | } | |
6762 | if (ordered) | |
6763 | btrfs_put_ordered_extent(ordered); | |
6764 | ||
6765 | extent_locked = 1; | |
6766 | continue; | |
6767 | } | |
6768 | ||
6769 | if (nr_extents == 1) { | |
6770 | /* update extent pointer in place */ | |
6771 | btrfs_set_file_extent_disk_bytenr(leaf, fi, | |
6772 | new_extents[0].disk_bytenr); | |
6773 | btrfs_set_file_extent_disk_num_bytes(leaf, fi, | |
6774 | new_extents[0].disk_num_bytes); | |
6775 | btrfs_mark_buffer_dirty(leaf); | |
6776 | ||
6777 | btrfs_drop_extent_cache(inode, key.offset, | |
6778 | key.offset + num_bytes - 1, 0); | |
6779 | ||
6780 | ret = btrfs_inc_extent_ref(trans, root, | |
6781 | new_extents[0].disk_bytenr, | |
6782 | new_extents[0].disk_num_bytes, | |
6783 | leaf->start, | |
6784 | root->root_key.objectid, | |
6785 | trans->transid, | |
6786 | key.objectid); | |
6787 | BUG_ON(ret); | |
6788 | ||
6789 | ret = btrfs_free_extent(trans, root, | |
6790 | extent_key->objectid, | |
6791 | extent_key->offset, | |
6792 | leaf->start, | |
6793 | btrfs_header_owner(leaf), | |
6794 | btrfs_header_generation(leaf), | |
6795 | key.objectid, 0); | |
6796 | BUG_ON(ret); | |
6797 | ||
6798 | btrfs_release_path(root, path); | |
6799 | key.offset += num_bytes; | |
6800 | } else { | |
6801 | BUG_ON(1); | |
6802 | #if 0 | |
6803 | u64 alloc_hint; | |
6804 | u64 extent_len; | |
6805 | int i; | |
6806 | /* | |
6807 | * drop old extent pointer at first, then insert the | |
6808 | * new pointers one bye one | |
6809 | */ | |
6810 | btrfs_release_path(root, path); | |
6811 | ret = btrfs_drop_extents(trans, root, inode, key.offset, | |
6812 | key.offset + num_bytes, | |
6813 | key.offset, &alloc_hint); | |
6814 | BUG_ON(ret); | |
6815 | ||
6816 | for (i = 0; i < nr_extents; i++) { | |
6817 | if (ext_offset >= new_extents[i].num_bytes) { | |
6818 | ext_offset -= new_extents[i].num_bytes; | |
6819 | continue; | |
6820 | } | |
6821 | extent_len = min(new_extents[i].num_bytes - | |
6822 | ext_offset, num_bytes); | |
6823 | ||
6824 | ret = btrfs_insert_empty_item(trans, root, | |
6825 | path, &key, | |
6826 | sizeof(*fi)); | |
6827 | BUG_ON(ret); | |
6828 | ||
6829 | leaf = path->nodes[0]; | |
6830 | fi = btrfs_item_ptr(leaf, path->slots[0], | |
6831 | struct btrfs_file_extent_item); | |
6832 | btrfs_set_file_extent_generation(leaf, fi, | |
6833 | trans->transid); | |
6834 | btrfs_set_file_extent_type(leaf, fi, | |
6835 | BTRFS_FILE_EXTENT_REG); | |
6836 | btrfs_set_file_extent_disk_bytenr(leaf, fi, | |
6837 | new_extents[i].disk_bytenr); | |
6838 | btrfs_set_file_extent_disk_num_bytes(leaf, fi, | |
6839 | new_extents[i].disk_num_bytes); | |
6840 | btrfs_set_file_extent_ram_bytes(leaf, fi, | |
6841 | new_extents[i].ram_bytes); | |
6842 | ||
6843 | btrfs_set_file_extent_compression(leaf, fi, | |
6844 | new_extents[i].compression); | |
6845 | btrfs_set_file_extent_encryption(leaf, fi, | |
6846 | new_extents[i].encryption); | |
6847 | btrfs_set_file_extent_other_encoding(leaf, fi, | |
6848 | new_extents[i].other_encoding); | |
6849 | ||
6850 | btrfs_set_file_extent_num_bytes(leaf, fi, | |
6851 | extent_len); | |
6852 | ext_offset += new_extents[i].offset; | |
6853 | btrfs_set_file_extent_offset(leaf, fi, | |
6854 | ext_offset); | |
6855 | btrfs_mark_buffer_dirty(leaf); | |
6856 | ||
6857 | btrfs_drop_extent_cache(inode, key.offset, | |
6858 | key.offset + extent_len - 1, 0); | |
6859 | ||
6860 | ret = btrfs_inc_extent_ref(trans, root, | |
6861 | new_extents[i].disk_bytenr, | |
6862 | new_extents[i].disk_num_bytes, | |
6863 | leaf->start, | |
6864 | root->root_key.objectid, | |
6865 | trans->transid, key.objectid); | |
6866 | BUG_ON(ret); | |
6867 | btrfs_release_path(root, path); | |
6868 | ||
6869 | inode_add_bytes(inode, extent_len); | |
6870 | ||
6871 | ext_offset = 0; | |
6872 | num_bytes -= extent_len; | |
6873 | key.offset += extent_len; | |
6874 | ||
6875 | if (num_bytes == 0) | |
6876 | break; | |
6877 | } | |
6878 | BUG_ON(i >= nr_extents); | |
6879 | #endif | |
6880 | } | |
6881 | ||
6882 | if (extent_locked) { | |
6883 | unlock_extent(&BTRFS_I(inode)->io_tree, lock_start, | |
6884 | lock_end, GFP_NOFS); | |
6885 | extent_locked = 0; | |
6886 | } | |
6887 | skip: | |
6888 | if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS && | |
6889 | key.offset >= search_end) | |
6890 | break; | |
6891 | ||
6892 | cond_resched(); | |
6893 | } | |
6894 | ret = 0; | |
6895 | out: | |
6896 | btrfs_release_path(root, path); | |
6897 | if (inode) { | |
6898 | mutex_unlock(&inode->i_mutex); | |
6899 | if (extent_locked) { | |
6900 | unlock_extent(&BTRFS_I(inode)->io_tree, lock_start, | |
6901 | lock_end, GFP_NOFS); | |
6902 | } | |
6903 | iput(inode); | |
6904 | } | |
6905 | return ret; | |
6906 | } | |
6907 | ||
6908 | int btrfs_reloc_tree_cache_ref(struct btrfs_trans_handle *trans, | |
6909 | struct btrfs_root *root, | |
6910 | struct extent_buffer *buf, u64 orig_start) | |
6911 | { | |
6912 | int level; | |
6913 | int ret; | |
6914 | ||
6915 | BUG_ON(btrfs_header_generation(buf) != trans->transid); | |
6916 | BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID); | |
6917 | ||
6918 | level = btrfs_header_level(buf); | |
6919 | if (level == 0) { | |
6920 | struct btrfs_leaf_ref *ref; | |
6921 | struct btrfs_leaf_ref *orig_ref; | |
6922 | ||
6923 | orig_ref = btrfs_lookup_leaf_ref(root, orig_start); | |
6924 | if (!orig_ref) | |
6925 | return -ENOENT; | |
6926 | ||
6927 | ref = btrfs_alloc_leaf_ref(root, orig_ref->nritems); | |
6928 | if (!ref) { | |
6929 | btrfs_free_leaf_ref(root, orig_ref); | |
6930 | return -ENOMEM; | |
6931 | } | |
6932 | ||
6933 | ref->nritems = orig_ref->nritems; | |
6934 | memcpy(ref->extents, orig_ref->extents, | |
6935 | sizeof(ref->extents[0]) * ref->nritems); | |
6936 | ||
6937 | btrfs_free_leaf_ref(root, orig_ref); | |
6938 | ||
6939 | ref->root_gen = trans->transid; | |
6940 | ref->bytenr = buf->start; | |
6941 | ref->owner = btrfs_header_owner(buf); | |
6942 | ref->generation = btrfs_header_generation(buf); | |
6943 | ||
6944 | ret = btrfs_add_leaf_ref(root, ref, 0); | |
6945 | WARN_ON(ret); | |
6946 | btrfs_free_leaf_ref(root, ref); | |
6947 | } | |
6948 | return 0; | |
6949 | } | |
6950 | ||
6951 | static noinline int invalidate_extent_cache(struct btrfs_root *root, | |
6952 | struct extent_buffer *leaf, | |
6953 | struct btrfs_block_group_cache *group, | |
6954 | struct btrfs_root *target_root) | |
6955 | { | |
6956 | struct btrfs_key key; | |
6957 | struct inode *inode = NULL; | |
6958 | struct btrfs_file_extent_item *fi; | |
6959 | struct extent_state *cached_state = NULL; | |
6960 | u64 num_bytes; | |
6961 | u64 skip_objectid = 0; | |
6962 | u32 nritems; | |
6963 | u32 i; | |
6964 | ||
6965 | nritems = btrfs_header_nritems(leaf); | |
6966 | for (i = 0; i < nritems; i++) { | |
6967 | btrfs_item_key_to_cpu(leaf, &key, i); | |
6968 | if (key.objectid == skip_objectid || | |
6969 | key.type != BTRFS_EXTENT_DATA_KEY) | |
6970 | continue; | |
6971 | fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); | |
6972 | if (btrfs_file_extent_type(leaf, fi) == | |
6973 | BTRFS_FILE_EXTENT_INLINE) | |
6974 | continue; | |
6975 | if (btrfs_file_extent_disk_bytenr(leaf, fi) == 0) | |
6976 | continue; | |
6977 | if (!inode || inode->i_ino != key.objectid) { | |
6978 | iput(inode); | |
6979 | inode = btrfs_ilookup(target_root->fs_info->sb, | |
6980 | key.objectid, target_root, 1); | |
6981 | } | |
6982 | if (!inode) { | |
6983 | skip_objectid = key.objectid; | |
6984 | continue; | |
6985 | } | |
6986 | num_bytes = btrfs_file_extent_num_bytes(leaf, fi); | |
6987 | ||
6988 | lock_extent_bits(&BTRFS_I(inode)->io_tree, key.offset, | |
6989 | key.offset + num_bytes - 1, 0, &cached_state, | |
6990 | GFP_NOFS); | |
6991 | btrfs_drop_extent_cache(inode, key.offset, | |
6992 | key.offset + num_bytes - 1, 1); | |
6993 | unlock_extent_cached(&BTRFS_I(inode)->io_tree, key.offset, | |
6994 | key.offset + num_bytes - 1, &cached_state, | |
6995 | GFP_NOFS); | |
6996 | cond_resched(); | |
6997 | } | |
6998 | iput(inode); | |
6999 | return 0; | |
7000 | } | |
7001 | ||
7002 | static noinline int replace_extents_in_leaf(struct btrfs_trans_handle *trans, | |
7003 | struct btrfs_root *root, | |
7004 | struct extent_buffer *leaf, | |
7005 | struct btrfs_block_group_cache *group, | |
7006 | struct inode *reloc_inode) | |
7007 | { | |
7008 | struct btrfs_key key; | |
7009 | struct btrfs_key extent_key; | |
7010 | struct btrfs_file_extent_item *fi; | |
7011 | struct btrfs_leaf_ref *ref; | |
7012 | struct disk_extent *new_extent; | |
7013 | u64 bytenr; | |
7014 | u64 num_bytes; | |
7015 | u32 nritems; | |
7016 | u32 i; | |
7017 | int ext_index; | |
7018 | int nr_extent; | |
7019 | int ret; | |
7020 | ||
7021 | new_extent = kmalloc(sizeof(*new_extent), GFP_NOFS); | |
7022 | BUG_ON(!new_extent); | |
7023 | ||
7024 | ref = btrfs_lookup_leaf_ref(root, leaf->start); | |
7025 | BUG_ON(!ref); | |
7026 | ||
7027 | ext_index = -1; | |
7028 | nritems = btrfs_header_nritems(leaf); | |
7029 | for (i = 0; i < nritems; i++) { | |
7030 | btrfs_item_key_to_cpu(leaf, &key, i); | |
7031 | if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) | |
7032 | continue; | |
7033 | fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); | |
7034 | if (btrfs_file_extent_type(leaf, fi) == | |
7035 | BTRFS_FILE_EXTENT_INLINE) | |
7036 | continue; | |
7037 | bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); | |
7038 | num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi); | |
7039 | if (bytenr == 0) | |
7040 | continue; | |
7041 | ||
7042 | ext_index++; | |
7043 | if (bytenr >= group->key.objectid + group->key.offset || | |
7044 | bytenr + num_bytes <= group->key.objectid) | |
7045 | continue; | |
7046 | ||
7047 | extent_key.objectid = bytenr; | |
7048 | extent_key.offset = num_bytes; | |
7049 | extent_key.type = BTRFS_EXTENT_ITEM_KEY; | |
7050 | nr_extent = 1; | |
7051 | ret = get_new_locations(reloc_inode, &extent_key, | |
7052 | group->key.objectid, 1, | |
7053 | &new_extent, &nr_extent); | |
7054 | if (ret > 0) | |
7055 | continue; | |
7056 | BUG_ON(ret < 0); | |
7057 | ||
7058 | BUG_ON(ref->extents[ext_index].bytenr != bytenr); | |
7059 | BUG_ON(ref->extents[ext_index].num_bytes != num_bytes); | |
7060 | ref->extents[ext_index].bytenr = new_extent->disk_bytenr; | |
7061 | ref->extents[ext_index].num_bytes = new_extent->disk_num_bytes; | |
7062 | ||
7063 | btrfs_set_file_extent_disk_bytenr(leaf, fi, | |
7064 | new_extent->disk_bytenr); | |
7065 | btrfs_set_file_extent_disk_num_bytes(leaf, fi, | |
7066 | new_extent->disk_num_bytes); | |
7067 | btrfs_mark_buffer_dirty(leaf); | |
7068 | ||
7069 | ret = btrfs_inc_extent_ref(trans, root, | |
7070 | new_extent->disk_bytenr, | |
7071 | new_extent->disk_num_bytes, | |
7072 | leaf->start, | |
7073 | root->root_key.objectid, | |
7074 | trans->transid, key.objectid); | |
7075 | BUG_ON(ret); | |
7076 | ||
7077 | ret = btrfs_free_extent(trans, root, | |
7078 | bytenr, num_bytes, leaf->start, | |
7079 | btrfs_header_owner(leaf), | |
7080 | btrfs_header_generation(leaf), | |
7081 | key.objectid, 0); | |
7082 | BUG_ON(ret); | |
7083 | cond_resched(); | |
7084 | } | |
7085 | kfree(new_extent); | |
7086 | BUG_ON(ext_index + 1 != ref->nritems); | |
7087 | btrfs_free_leaf_ref(root, ref); | |
7088 | return 0; | |
7089 | } | |
7090 | ||
7091 | int btrfs_free_reloc_root(struct btrfs_trans_handle *trans, | |
7092 | struct btrfs_root *root) | |
7093 | { | |
7094 | struct btrfs_root *reloc_root; | |
7095 | int ret; | |
7096 | ||
7097 | if (root->reloc_root) { | |
7098 | reloc_root = root->reloc_root; | |
7099 | root->reloc_root = NULL; | |
7100 | list_add(&reloc_root->dead_list, | |
7101 | &root->fs_info->dead_reloc_roots); | |
7102 | ||
7103 | btrfs_set_root_bytenr(&reloc_root->root_item, | |
7104 | reloc_root->node->start); | |
7105 | btrfs_set_root_level(&root->root_item, | |
7106 | btrfs_header_level(reloc_root->node)); | |
7107 | memset(&reloc_root->root_item.drop_progress, 0, | |
7108 | sizeof(struct btrfs_disk_key)); | |
7109 | reloc_root->root_item.drop_level = 0; | |
7110 | ||
7111 | ret = btrfs_update_root(trans, root->fs_info->tree_root, | |
7112 | &reloc_root->root_key, | |
7113 | &reloc_root->root_item); | |
7114 | BUG_ON(ret); | |
7115 | } | |
7116 | return 0; | |
7117 | } | |
7118 | ||
7119 | int btrfs_drop_dead_reloc_roots(struct btrfs_root *root) | |
7120 | { | |
7121 | struct btrfs_trans_handle *trans; | |
7122 | struct btrfs_root *reloc_root; | |
7123 | struct btrfs_root *prev_root = NULL; | |
7124 | struct list_head dead_roots; | |
7125 | int ret; | |
7126 | unsigned long nr; | |
7127 | ||
7128 | INIT_LIST_HEAD(&dead_roots); | |
7129 | list_splice_init(&root->fs_info->dead_reloc_roots, &dead_roots); | |
7130 | ||
7131 | while (!list_empty(&dead_roots)) { | |
7132 | reloc_root = list_entry(dead_roots.prev, | |
7133 | struct btrfs_root, dead_list); | |
7134 | list_del_init(&reloc_root->dead_list); | |
7135 | ||
7136 | BUG_ON(reloc_root->commit_root != NULL); | |
7137 | while (1) { | |
7138 | trans = btrfs_join_transaction(root, 1); | |
7139 | BUG_ON(!trans); | |
7140 | ||
7141 | mutex_lock(&root->fs_info->drop_mutex); | |
7142 | ret = btrfs_drop_snapshot(trans, reloc_root); | |
7143 | if (ret != -EAGAIN) | |
7144 | break; | |
7145 | mutex_unlock(&root->fs_info->drop_mutex); | |
7146 | ||
7147 | nr = trans->blocks_used; | |
7148 | ret = btrfs_end_transaction(trans, root); | |
7149 | BUG_ON(ret); | |
7150 | btrfs_btree_balance_dirty(root, nr); | |
7151 | } | |
7152 | ||
7153 | free_extent_buffer(reloc_root->node); | |
7154 | ||
7155 | ret = btrfs_del_root(trans, root->fs_info->tree_root, | |
7156 | &reloc_root->root_key); | |
7157 | BUG_ON(ret); | |
7158 | mutex_unlock(&root->fs_info->drop_mutex); | |
7159 | ||
7160 | nr = trans->blocks_used; | |
7161 | ret = btrfs_end_transaction(trans, root); | |
7162 | BUG_ON(ret); | |
7163 | btrfs_btree_balance_dirty(root, nr); | |
7164 | ||
7165 | kfree(prev_root); | |
7166 | prev_root = reloc_root; | |
7167 | } | |
7168 | if (prev_root) { | |
7169 | btrfs_remove_leaf_refs(prev_root, (u64)-1, 0); | |
7170 | kfree(prev_root); | |
7171 | } | |
7172 | return 0; | |
7173 | } | |
7174 | ||
7175 | int btrfs_add_dead_reloc_root(struct btrfs_root *root) | |
7176 | { | |
7177 | list_add(&root->dead_list, &root->fs_info->dead_reloc_roots); | |
7178 | return 0; | |
7179 | } | |
7180 | ||
7181 | int btrfs_cleanup_reloc_trees(struct btrfs_root *root) | |
7182 | { | |
7183 | struct btrfs_root *reloc_root; | |
7184 | struct btrfs_trans_handle *trans; | |
7185 | struct btrfs_key location; | |
7186 | int found; | |
7187 | int ret; | |
7188 | ||
7189 | mutex_lock(&root->fs_info->tree_reloc_mutex); | |
7190 | ret = btrfs_find_dead_roots(root, BTRFS_TREE_RELOC_OBJECTID, NULL); | |
7191 | BUG_ON(ret); | |
7192 | found = !list_empty(&root->fs_info->dead_reloc_roots); | |
7193 | mutex_unlock(&root->fs_info->tree_reloc_mutex); | |
7194 | ||
7195 | if (found) { | |
7196 | trans = btrfs_start_transaction(root, 1); | |
7197 | BUG_ON(!trans); | |
7198 | ret = btrfs_commit_transaction(trans, root); | |
7199 | BUG_ON(ret); | |
7200 | } | |
7201 | ||
7202 | location.objectid = BTRFS_DATA_RELOC_TREE_OBJECTID; | |
7203 | location.offset = (u64)-1; | |
7204 | location.type = BTRFS_ROOT_ITEM_KEY; | |
7205 | ||
7206 | reloc_root = btrfs_read_fs_root_no_name(root->fs_info, &location); | |
7207 | BUG_ON(!reloc_root); | |
7208 | btrfs_orphan_cleanup(reloc_root); | |
7209 | return 0; | |
7210 | } | |
7211 | ||
7212 | static noinline int init_reloc_tree(struct btrfs_trans_handle *trans, | |
7213 | struct btrfs_root *root) | |
7214 | { | |
7215 | struct btrfs_root *reloc_root; | |
7216 | struct extent_buffer *eb; | |
7217 | struct btrfs_root_item *root_item; | |
7218 | struct btrfs_key root_key; | |
7219 | int ret; | |
7220 | ||
7221 | BUG_ON(!root->ref_cows); | |
7222 | if (root->reloc_root) | |
7223 | return 0; | |
7224 | ||
7225 | root_item = kmalloc(sizeof(*root_item), GFP_NOFS); | |
7226 | BUG_ON(!root_item); | |
7227 | ||
7228 | ret = btrfs_copy_root(trans, root, root->commit_root, | |
7229 | &eb, BTRFS_TREE_RELOC_OBJECTID); | |
7230 | BUG_ON(ret); | |
7231 | ||
7232 | root_key.objectid = BTRFS_TREE_RELOC_OBJECTID; | |
7233 | root_key.offset = root->root_key.objectid; | |
7234 | root_key.type = BTRFS_ROOT_ITEM_KEY; | |
7235 | ||
7236 | memcpy(root_item, &root->root_item, sizeof(root_item)); | |
7237 | btrfs_set_root_refs(root_item, 0); | |
7238 | btrfs_set_root_bytenr(root_item, eb->start); | |
7239 | btrfs_set_root_level(root_item, btrfs_header_level(eb)); | |
7240 | btrfs_set_root_generation(root_item, trans->transid); | |
7241 | ||
7242 | btrfs_tree_unlock(eb); | |
7243 | free_extent_buffer(eb); | |
7244 | ||
7245 | ret = btrfs_insert_root(trans, root->fs_info->tree_root, | |
7246 | &root_key, root_item); | |
7247 | BUG_ON(ret); | |
7248 | kfree(root_item); | |
7249 | ||
7250 | reloc_root = btrfs_read_fs_root_no_radix(root->fs_info->tree_root, | |
7251 | &root_key); | |
7252 | BUG_ON(!reloc_root); | |
7253 | reloc_root->last_trans = trans->transid; | |
7254 | reloc_root->commit_root = NULL; | |
7255 | reloc_root->ref_tree = &root->fs_info->reloc_ref_tree; | |
7256 | ||
7257 | root->reloc_root = reloc_root; | |
7258 | return 0; | |
7259 | } | |
7260 | ||
7261 | /* | |
7262 | * Core function of space balance. | |
7263 | * | |
7264 | * The idea is using reloc trees to relocate tree blocks in reference | |
7265 | * counted roots. There is one reloc tree for each subvol, and all | |
7266 | * reloc trees share same root key objectid. Reloc trees are snapshots | |
7267 | * of the latest committed roots of subvols (root->commit_root). | |
7268 | * | |
7269 | * To relocate a tree block referenced by a subvol, there are two steps. | |
7270 | * COW the block through subvol's reloc tree, then update block pointer | |
7271 | * in the subvol to point to the new block. Since all reloc trees share | |
7272 | * same root key objectid, doing special handing for tree blocks owned | |
7273 | * by them is easy. Once a tree block has been COWed in one reloc tree, | |
7274 | * we can use the resulting new block directly when the same block is | |
7275 | * required to COW again through other reloc trees. By this way, relocated | |
7276 | * tree blocks are shared between reloc trees, so they are also shared | |
7277 | * between subvols. | |
7278 | */ | |
7279 | static noinline int relocate_one_path(struct btrfs_trans_handle *trans, | |
7280 | struct btrfs_root *root, | |
7281 | struct btrfs_path *path, | |
7282 | struct btrfs_key *first_key, | |
7283 | struct btrfs_ref_path *ref_path, | |
7284 | struct btrfs_block_group_cache *group, | |
7285 | struct inode *reloc_inode) | |
7286 | { | |
7287 | struct btrfs_root *reloc_root; | |
7288 | struct extent_buffer *eb = NULL; | |
7289 | struct btrfs_key *keys; | |
7290 | u64 *nodes; | |
7291 | int level; | |
7292 | int shared_level; | |
7293 | int lowest_level = 0; | |
7294 | int ret; | |
7295 | ||
7296 | if (ref_path->owner_objectid < BTRFS_FIRST_FREE_OBJECTID) | |
7297 | lowest_level = ref_path->owner_objectid; | |
7298 | ||
7299 | if (!root->ref_cows) { | |
7300 | path->lowest_level = lowest_level; | |
7301 | ret = btrfs_search_slot(trans, root, first_key, path, 0, 1); | |
7302 | BUG_ON(ret < 0); | |
7303 | path->lowest_level = 0; | |
7304 | btrfs_release_path(root, path); | |
7305 | return 0; | |
7306 | } | |
7307 | ||
7308 | mutex_lock(&root->fs_info->tree_reloc_mutex); | |
7309 | ret = init_reloc_tree(trans, root); | |
7310 | BUG_ON(ret); | |
7311 | reloc_root = root->reloc_root; | |
7312 | ||
7313 | shared_level = ref_path->shared_level; | |
7314 | ref_path->shared_level = BTRFS_MAX_LEVEL - 1; | |
7315 | ||
7316 | keys = ref_path->node_keys; | |
7317 | nodes = ref_path->new_nodes; | |
7318 | memset(&keys[shared_level + 1], 0, | |
7319 | sizeof(*keys) * (BTRFS_MAX_LEVEL - shared_level - 1)); | |
7320 | memset(&nodes[shared_level + 1], 0, | |
7321 | sizeof(*nodes) * (BTRFS_MAX_LEVEL - shared_level - 1)); | |
7322 | ||
7323 | if (nodes[lowest_level] == 0) { | |
7324 | path->lowest_level = lowest_level; | |
7325 | ret = btrfs_search_slot(trans, reloc_root, first_key, path, | |
7326 | 0, 1); | |
7327 | BUG_ON(ret); | |
7328 | for (level = lowest_level; level < BTRFS_MAX_LEVEL; level++) { | |
7329 | eb = path->nodes[level]; | |
7330 | if (!eb || eb == reloc_root->node) | |
7331 | break; | |
7332 | nodes[level] = eb->start; | |
7333 | if (level == 0) | |
7334 | btrfs_item_key_to_cpu(eb, &keys[level], 0); | |
7335 | else | |
7336 | btrfs_node_key_to_cpu(eb, &keys[level], 0); | |
7337 | } | |
7338 | if (nodes[0] && | |
7339 | ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) { | |
7340 | eb = path->nodes[0]; | |
7341 | ret = replace_extents_in_leaf(trans, reloc_root, eb, | |
7342 | group, reloc_inode); | |
7343 | BUG_ON(ret); | |
7344 | } | |
7345 | btrfs_release_path(reloc_root, path); | |
7346 | } else { | |
7347 | ret = btrfs_merge_path(trans, reloc_root, keys, nodes, | |
7348 | lowest_level); | |
7349 | BUG_ON(ret); | |
7350 | } | |
7351 | ||
7352 | /* | |
7353 | * replace tree blocks in the fs tree with tree blocks in | |
7354 | * the reloc tree. | |
7355 | */ | |
7356 | ret = btrfs_merge_path(trans, root, keys, nodes, lowest_level); | |
7357 | BUG_ON(ret < 0); | |
7358 | ||
7359 | if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) { | |
7360 | ret = btrfs_search_slot(trans, reloc_root, first_key, path, | |
7361 | 0, 0); | |
7362 | BUG_ON(ret); | |
7363 | extent_buffer_get(path->nodes[0]); | |
7364 | eb = path->nodes[0]; | |
7365 | btrfs_release_path(reloc_root, path); | |
7366 | ret = invalidate_extent_cache(reloc_root, eb, group, root); | |
7367 | BUG_ON(ret); | |
7368 | free_extent_buffer(eb); | |
7369 | } | |
7370 | ||
7371 | mutex_unlock(&root->fs_info->tree_reloc_mutex); | |
7372 | path->lowest_level = 0; | |
7373 | return 0; | |
7374 | } | |
7375 | ||
7376 | static noinline int relocate_tree_block(struct btrfs_trans_handle *trans, | |
7377 | struct btrfs_root *root, | |
7378 | struct btrfs_path *path, | |
7379 | struct btrfs_key *first_key, | |
7380 | struct btrfs_ref_path *ref_path) | |
7381 | { | |
7382 | int ret; | |
7383 | ||
7384 | ret = relocate_one_path(trans, root, path, first_key, | |
7385 | ref_path, NULL, NULL); | |
7386 | BUG_ON(ret); | |
7387 | ||
7388 | return 0; | |
7389 | } | |
7390 | ||
7391 | static noinline int del_extent_zero(struct btrfs_trans_handle *trans, | |
7392 | struct btrfs_root *extent_root, | |
7393 | struct btrfs_path *path, | |
7394 | struct btrfs_key *extent_key) | |
7395 | { | |
7396 | int ret; | |
7397 | ||
7398 | ret = btrfs_search_slot(trans, extent_root, extent_key, path, -1, 1); | |
7399 | if (ret) | |
7400 | goto out; | |
7401 | ret = btrfs_del_item(trans, extent_root, path); | |
7402 | out: | |
7403 | btrfs_release_path(extent_root, path); | |
7404 | return ret; | |
7405 | } | |
7406 | ||
7407 | static noinline struct btrfs_root *read_ref_root(struct btrfs_fs_info *fs_info, | |
7408 | struct btrfs_ref_path *ref_path) | |
7409 | { | |
7410 | struct btrfs_key root_key; | |
7411 | ||
7412 | root_key.objectid = ref_path->root_objectid; | |
7413 | root_key.type = BTRFS_ROOT_ITEM_KEY; | |
7414 | if (is_cowonly_root(ref_path->root_objectid)) | |
7415 | root_key.offset = 0; | |
7416 | else | |
7417 | root_key.offset = (u64)-1; | |
7418 | ||
7419 | return btrfs_read_fs_root_no_name(fs_info, &root_key); | |
7420 | } | |
7421 | ||
7422 | static noinline int relocate_one_extent(struct btrfs_root *extent_root, | |
7423 | struct btrfs_path *path, | |
7424 | struct btrfs_key *extent_key, | |
7425 | struct btrfs_block_group_cache *group, | |
7426 | struct inode *reloc_inode, int pass) | |
7427 | { | |
7428 | struct btrfs_trans_handle *trans; | |
7429 | struct btrfs_root *found_root; | |
7430 | struct btrfs_ref_path *ref_path = NULL; | |
7431 | struct disk_extent *new_extents = NULL; | |
7432 | int nr_extents = 0; | |
7433 | int loops; | |
7434 | int ret; | |
7435 | int level; | |
7436 | struct btrfs_key first_key; | |
7437 | u64 prev_block = 0; | |
7438 | ||
7439 | ||
7440 | trans = btrfs_start_transaction(extent_root, 1); | |
7441 | BUG_ON(!trans); | |
7442 | ||
7443 | if (extent_key->objectid == 0) { | |
7444 | ret = del_extent_zero(trans, extent_root, path, extent_key); | |
7445 | goto out; | |
7446 | } | |
7447 | ||
7448 | ref_path = kmalloc(sizeof(*ref_path), GFP_NOFS); | |
7449 | if (!ref_path) { | |
7450 | ret = -ENOMEM; | |
7451 | goto out; | |
7452 | } | |
7453 | ||
7454 | for (loops = 0; ; loops++) { | |
7455 | if (loops == 0) { | |
7456 | ret = btrfs_first_ref_path(trans, extent_root, ref_path, | |
7457 | extent_key->objectid); | |
7458 | } else { | |
7459 | ret = btrfs_next_ref_path(trans, extent_root, ref_path); | |
7460 | } | |
7461 | if (ret < 0) | |
7462 | goto out; | |
7463 | if (ret > 0) | |
7464 | break; | |
7465 | ||
7466 | if (ref_path->root_objectid == BTRFS_TREE_LOG_OBJECTID || | |
7467 | ref_path->root_objectid == BTRFS_TREE_RELOC_OBJECTID) | |
7468 | continue; | |
7469 | ||
7470 | found_root = read_ref_root(extent_root->fs_info, ref_path); | |
7471 | BUG_ON(!found_root); | |
7472 | /* | |
7473 | * for reference counted tree, only process reference paths | |
7474 | * rooted at the latest committed root. | |
7475 | */ | |
7476 | if (found_root->ref_cows && | |
7477 | ref_path->root_generation != found_root->root_key.offset) | |
7478 | continue; | |
7479 | ||
7480 | if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) { | |
7481 | if (pass == 0) { | |
7482 | /* | |
7483 | * copy data extents to new locations | |
7484 | */ | |
7485 | u64 group_start = group->key.objectid; | |
7486 | ret = relocate_data_extent(reloc_inode, | |
7487 | extent_key, | |
7488 | group_start); | |
7489 | if (ret < 0) | |
7490 | goto out; | |
7491 | break; | |
7492 | } | |
7493 | level = 0; | |
7494 | } else { | |
7495 | level = ref_path->owner_objectid; | |
7496 | } | |
7497 | ||
7498 | if (prev_block != ref_path->nodes[level]) { | |
7499 | struct extent_buffer *eb; | |
7500 | u64 block_start = ref_path->nodes[level]; | |
7501 | u64 block_size = btrfs_level_size(found_root, level); | |
7502 | ||
7503 | eb = read_tree_block(found_root, block_start, | |
7504 | block_size, 0); | |
7505 | btrfs_tree_lock(eb); | |
7506 | BUG_ON(level != btrfs_header_level(eb)); | |
7507 | ||
7508 | if (level == 0) | |
7509 | btrfs_item_key_to_cpu(eb, &first_key, 0); | |
7510 | else | |
7511 | btrfs_node_key_to_cpu(eb, &first_key, 0); | |
7512 | ||
7513 | btrfs_tree_unlock(eb); | |
7514 | free_extent_buffer(eb); | |
7515 | prev_block = block_start; | |
7516 | } | |
7517 | ||
7518 | mutex_lock(&extent_root->fs_info->trans_mutex); | |
7519 | btrfs_record_root_in_trans(found_root); | |
7520 | mutex_unlock(&extent_root->fs_info->trans_mutex); | |
7521 | if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) { | |
7522 | /* | |
7523 | * try to update data extent references while | |
7524 | * keeping metadata shared between snapshots. | |
7525 | */ | |
7526 | if (pass == 1) { | |
7527 | ret = relocate_one_path(trans, found_root, | |
7528 | path, &first_key, ref_path, | |
7529 | group, reloc_inode); | |
7530 | if (ret < 0) | |
7531 | goto out; | |
7532 | continue; | |
7533 | } | |
7534 | /* | |
7535 | * use fallback method to process the remaining | |
7536 | * references. | |
7537 | */ | |
7538 | if (!new_extents) { | |
7539 | u64 group_start = group->key.objectid; | |
7540 | new_extents = kmalloc(sizeof(*new_extents), | |
7541 | GFP_NOFS); | |
7542 | nr_extents = 1; | |
7543 | ret = get_new_locations(reloc_inode, | |
7544 | extent_key, | |
7545 | group_start, 1, | |
7546 | &new_extents, | |
7547 | &nr_extents); | |
7548 | if (ret) | |
7549 | goto out; | |
7550 | } | |
7551 | ret = replace_one_extent(trans, found_root, | |
7552 | path, extent_key, | |
7553 | &first_key, ref_path, | |
7554 | new_extents, nr_extents); | |
7555 | } else { | |
7556 | ret = relocate_tree_block(trans, found_root, path, | |
7557 | &first_key, ref_path); | |
7558 | } | |
7559 | if (ret < 0) | |
7560 | goto out; | |
7561 | } | |
7562 | ret = 0; | |
7563 | out: | |
7564 | btrfs_end_transaction(trans, extent_root); | |
7565 | kfree(new_extents); | |
7566 | kfree(ref_path); | |
7567 | return ret; | |
7568 | } | |
7569 | #endif | |
7570 | ||
7571 | static u64 update_block_group_flags(struct btrfs_root *root, u64 flags) | |
7572 | { | |
7573 | u64 num_devices; | |
7574 | u64 stripped = BTRFS_BLOCK_GROUP_RAID0 | | |
7575 | BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10; | |
7576 | ||
7577 | num_devices = root->fs_info->fs_devices->rw_devices; | |
7578 | if (num_devices == 1) { | |
7579 | stripped |= BTRFS_BLOCK_GROUP_DUP; | |
7580 | stripped = flags & ~stripped; | |
7581 | ||
7582 | /* turn raid0 into single device chunks */ | |
7583 | if (flags & BTRFS_BLOCK_GROUP_RAID0) | |
7584 | return stripped; | |
7585 | ||
7586 | /* turn mirroring into duplication */ | |
7587 | if (flags & (BTRFS_BLOCK_GROUP_RAID1 | | |
7588 | BTRFS_BLOCK_GROUP_RAID10)) | |
7589 | return stripped | BTRFS_BLOCK_GROUP_DUP; | |
7590 | return flags; | |
7591 | } else { | |
7592 | /* they already had raid on here, just return */ | |
7593 | if (flags & stripped) | |
7594 | return flags; | |
7595 | ||
7596 | stripped |= BTRFS_BLOCK_GROUP_DUP; | |
7597 | stripped = flags & ~stripped; | |
7598 | ||
7599 | /* switch duplicated blocks with raid1 */ | |
7600 | if (flags & BTRFS_BLOCK_GROUP_DUP) | |
7601 | return stripped | BTRFS_BLOCK_GROUP_RAID1; | |
7602 | ||
7603 | /* turn single device chunks into raid0 */ | |
7604 | return stripped | BTRFS_BLOCK_GROUP_RAID0; | |
7605 | } | |
7606 | return flags; | |
7607 | } | |
7608 | ||
7609 | static int set_block_group_ro(struct btrfs_block_group_cache *cache) | |
7610 | { | |
7611 | struct btrfs_space_info *sinfo = cache->space_info; | |
7612 | u64 num_bytes; | |
7613 | int ret = -ENOSPC; | |
7614 | ||
7615 | if (cache->ro) | |
7616 | return 0; | |
7617 | ||
7618 | spin_lock(&sinfo->lock); | |
7619 | spin_lock(&cache->lock); | |
7620 | num_bytes = cache->key.offset - cache->reserved - cache->pinned - | |
7621 | cache->bytes_super - btrfs_block_group_used(&cache->item); | |
7622 | ||
7623 | if (sinfo->bytes_used + sinfo->bytes_reserved + sinfo->bytes_pinned + | |
7624 | sinfo->bytes_may_use + sinfo->bytes_readonly + | |
7625 | cache->reserved_pinned + num_bytes < sinfo->total_bytes) { | |
7626 | sinfo->bytes_readonly += num_bytes; | |
7627 | sinfo->bytes_reserved += cache->reserved_pinned; | |
7628 | cache->reserved_pinned = 0; | |
7629 | cache->ro = 1; | |
7630 | ret = 0; | |
7631 | } | |
7632 | spin_unlock(&cache->lock); | |
7633 | spin_unlock(&sinfo->lock); | |
7634 | return ret; | |
7635 | } | |
7636 | ||
7637 | int btrfs_set_block_group_ro(struct btrfs_root *root, | |
7638 | struct btrfs_block_group_cache *cache) | |
7639 | ||
7640 | { | |
7641 | struct btrfs_trans_handle *trans; | |
7642 | u64 alloc_flags; | |
7643 | int ret; | |
7644 | ||
7645 | BUG_ON(cache->ro); | |
7646 | ||
7647 | trans = btrfs_join_transaction(root, 1); | |
7648 | BUG_ON(IS_ERR(trans)); | |
7649 | ||
7650 | alloc_flags = update_block_group_flags(root, cache->flags); | |
7651 | if (alloc_flags != cache->flags) | |
7652 | do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags, 1); | |
7653 | ||
7654 | ret = set_block_group_ro(cache); | |
7655 | if (!ret) | |
7656 | goto out; | |
7657 | alloc_flags = get_alloc_profile(root, cache->space_info->flags); | |
7658 | ret = do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags, 1); | |
7659 | if (ret < 0) | |
7660 | goto out; | |
7661 | ret = set_block_group_ro(cache); | |
7662 | out: | |
7663 | btrfs_end_transaction(trans, root); | |
7664 | return ret; | |
7665 | } | |
7666 | ||
7667 | int btrfs_set_block_group_rw(struct btrfs_root *root, | |
7668 | struct btrfs_block_group_cache *cache) | |
7669 | { | |
7670 | struct btrfs_space_info *sinfo = cache->space_info; | |
7671 | u64 num_bytes; | |
7672 | ||
7673 | BUG_ON(!cache->ro); | |
7674 | ||
7675 | spin_lock(&sinfo->lock); | |
7676 | spin_lock(&cache->lock); | |
7677 | num_bytes = cache->key.offset - cache->reserved - cache->pinned - | |
7678 | cache->bytes_super - btrfs_block_group_used(&cache->item); | |
7679 | sinfo->bytes_readonly -= num_bytes; | |
7680 | cache->ro = 0; | |
7681 | spin_unlock(&cache->lock); | |
7682 | spin_unlock(&sinfo->lock); | |
7683 | return 0; | |
7684 | } | |
7685 | ||
7686 | /* | |
7687 | * checks to see if its even possible to relocate this block group. | |
7688 | * | |
7689 | * @return - -1 if it's not a good idea to relocate this block group, 0 if its | |
7690 | * ok to go ahead and try. | |
7691 | */ | |
7692 | int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr) | |
7693 | { | |
7694 | struct btrfs_block_group_cache *block_group; | |
7695 | struct btrfs_space_info *space_info; | |
7696 | struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; | |
7697 | struct btrfs_device *device; | |
7698 | int full = 0; | |
7699 | int ret = 0; | |
7700 | ||
7701 | block_group = btrfs_lookup_block_group(root->fs_info, bytenr); | |
7702 | ||
7703 | /* odd, couldn't find the block group, leave it alone */ | |
7704 | if (!block_group) | |
7705 | return -1; | |
7706 | ||
7707 | /* no bytes used, we're good */ | |
7708 | if (!btrfs_block_group_used(&block_group->item)) | |
7709 | goto out; | |
7710 | ||
7711 | space_info = block_group->space_info; | |
7712 | spin_lock(&space_info->lock); | |
7713 | ||
7714 | full = space_info->full; | |
7715 | ||
7716 | /* | |
7717 | * if this is the last block group we have in this space, we can't | |
7718 | * relocate it unless we're able to allocate a new chunk below. | |
7719 | * | |
7720 | * Otherwise, we need to make sure we have room in the space to handle | |
7721 | * all of the extents from this block group. If we can, we're good | |
7722 | */ | |
7723 | if ((space_info->total_bytes != block_group->key.offset) && | |
7724 | (space_info->bytes_used + space_info->bytes_reserved + | |
7725 | space_info->bytes_pinned + space_info->bytes_readonly + | |
7726 | btrfs_block_group_used(&block_group->item) < | |
7727 | space_info->total_bytes)) { | |
7728 | spin_unlock(&space_info->lock); | |
7729 | goto out; | |
7730 | } | |
7731 | spin_unlock(&space_info->lock); | |
7732 | ||
7733 | /* | |
7734 | * ok we don't have enough space, but maybe we have free space on our | |
7735 | * devices to allocate new chunks for relocation, so loop through our | |
7736 | * alloc devices and guess if we have enough space. However, if we | |
7737 | * were marked as full, then we know there aren't enough chunks, and we | |
7738 | * can just return. | |
7739 | */ | |
7740 | ret = -1; | |
7741 | if (full) | |
7742 | goto out; | |
7743 | ||
7744 | mutex_lock(&root->fs_info->chunk_mutex); | |
7745 | list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) { | |
7746 | u64 min_free = btrfs_block_group_used(&block_group->item); | |
7747 | u64 dev_offset, max_avail; | |
7748 | ||
7749 | /* | |
7750 | * check to make sure we can actually find a chunk with enough | |
7751 | * space to fit our block group in. | |
7752 | */ | |
7753 | if (device->total_bytes > device->bytes_used + min_free) { | |
7754 | ret = find_free_dev_extent(NULL, device, min_free, | |
7755 | &dev_offset, &max_avail); | |
7756 | if (!ret) | |
7757 | break; | |
7758 | ret = -1; | |
7759 | } | |
7760 | } | |
7761 | mutex_unlock(&root->fs_info->chunk_mutex); | |
7762 | out: | |
7763 | btrfs_put_block_group(block_group); | |
7764 | return ret; | |
7765 | } | |
7766 | ||
7767 | static int find_first_block_group(struct btrfs_root *root, | |
7768 | struct btrfs_path *path, struct btrfs_key *key) | |
7769 | { | |
7770 | int ret = 0; | |
7771 | struct btrfs_key found_key; | |
7772 | struct extent_buffer *leaf; | |
7773 | int slot; | |
7774 | ||
7775 | ret = btrfs_search_slot(NULL, root, key, path, 0, 0); | |
7776 | if (ret < 0) | |
7777 | goto out; | |
7778 | ||
7779 | while (1) { | |
7780 | slot = path->slots[0]; | |
7781 | leaf = path->nodes[0]; | |
7782 | if (slot >= btrfs_header_nritems(leaf)) { | |
7783 | ret = btrfs_next_leaf(root, path); | |
7784 | if (ret == 0) | |
7785 | continue; | |
7786 | if (ret < 0) | |
7787 | goto out; | |
7788 | break; | |
7789 | } | |
7790 | btrfs_item_key_to_cpu(leaf, &found_key, slot); | |
7791 | ||
7792 | if (found_key.objectid >= key->objectid && | |
7793 | found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) { | |
7794 | ret = 0; | |
7795 | goto out; | |
7796 | } | |
7797 | path->slots[0]++; | |
7798 | } | |
7799 | out: | |
7800 | return ret; | |
7801 | } | |
7802 | ||
7803 | int btrfs_free_block_groups(struct btrfs_fs_info *info) | |
7804 | { | |
7805 | struct btrfs_block_group_cache *block_group; | |
7806 | struct btrfs_space_info *space_info; | |
7807 | struct btrfs_caching_control *caching_ctl; | |
7808 | struct rb_node *n; | |
7809 | ||
7810 | down_write(&info->extent_commit_sem); | |
7811 | while (!list_empty(&info->caching_block_groups)) { | |
7812 | caching_ctl = list_entry(info->caching_block_groups.next, | |
7813 | struct btrfs_caching_control, list); | |
7814 | list_del(&caching_ctl->list); | |
7815 | put_caching_control(caching_ctl); | |
7816 | } | |
7817 | up_write(&info->extent_commit_sem); | |
7818 | ||
7819 | spin_lock(&info->block_group_cache_lock); | |
7820 | while ((n = rb_last(&info->block_group_cache_tree)) != NULL) { | |
7821 | block_group = rb_entry(n, struct btrfs_block_group_cache, | |
7822 | cache_node); | |
7823 | rb_erase(&block_group->cache_node, | |
7824 | &info->block_group_cache_tree); | |
7825 | spin_unlock(&info->block_group_cache_lock); | |
7826 | ||
7827 | down_write(&block_group->space_info->groups_sem); | |
7828 | list_del(&block_group->list); | |
7829 | up_write(&block_group->space_info->groups_sem); | |
7830 | ||
7831 | if (block_group->cached == BTRFS_CACHE_STARTED) | |
7832 | wait_block_group_cache_done(block_group); | |
7833 | ||
7834 | btrfs_remove_free_space_cache(block_group); | |
7835 | btrfs_put_block_group(block_group); | |
7836 | ||
7837 | spin_lock(&info->block_group_cache_lock); | |
7838 | } | |
7839 | spin_unlock(&info->block_group_cache_lock); | |
7840 | ||
7841 | /* now that all the block groups are freed, go through and | |
7842 | * free all the space_info structs. This is only called during | |
7843 | * the final stages of unmount, and so we know nobody is | |
7844 | * using them. We call synchronize_rcu() once before we start, | |
7845 | * just to be on the safe side. | |
7846 | */ | |
7847 | synchronize_rcu(); | |
7848 | ||
7849 | while(!list_empty(&info->space_info)) { | |
7850 | space_info = list_entry(info->space_info.next, | |
7851 | struct btrfs_space_info, | |
7852 | list); | |
7853 | if (space_info->bytes_pinned > 0 || | |
7854 | space_info->bytes_reserved > 0) { | |
7855 | WARN_ON(1); | |
7856 | dump_space_info(space_info, 0, 0); | |
7857 | } | |
7858 | list_del(&space_info->list); | |
7859 | kfree(space_info); | |
7860 | } | |
7861 | return 0; | |
7862 | } | |
7863 | ||
7864 | static void __link_block_group(struct btrfs_space_info *space_info, | |
7865 | struct btrfs_block_group_cache *cache) | |
7866 | { | |
7867 | int index = get_block_group_index(cache); | |
7868 | ||
7869 | down_write(&space_info->groups_sem); | |
7870 | list_add_tail(&cache->list, &space_info->block_groups[index]); | |
7871 | up_write(&space_info->groups_sem); | |
7872 | } | |
7873 | ||
7874 | int btrfs_read_block_groups(struct btrfs_root *root) | |
7875 | { | |
7876 | struct btrfs_path *path; | |
7877 | int ret; | |
7878 | struct btrfs_block_group_cache *cache; | |
7879 | struct btrfs_fs_info *info = root->fs_info; | |
7880 | struct btrfs_space_info *space_info; | |
7881 | struct btrfs_key key; | |
7882 | struct btrfs_key found_key; | |
7883 | struct extent_buffer *leaf; | |
7884 | ||
7885 | root = info->extent_root; | |
7886 | key.objectid = 0; | |
7887 | key.offset = 0; | |
7888 | btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY); | |
7889 | path = btrfs_alloc_path(); | |
7890 | if (!path) | |
7891 | return -ENOMEM; | |
7892 | ||
7893 | while (1) { | |
7894 | ret = find_first_block_group(root, path, &key); | |
7895 | if (ret > 0) | |
7896 | break; | |
7897 | if (ret != 0) | |
7898 | goto error; | |
7899 | ||
7900 | leaf = path->nodes[0]; | |
7901 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); | |
7902 | cache = kzalloc(sizeof(*cache), GFP_NOFS); | |
7903 | if (!cache) { | |
7904 | ret = -ENOMEM; | |
7905 | goto error; | |
7906 | } | |
7907 | ||
7908 | atomic_set(&cache->count, 1); | |
7909 | spin_lock_init(&cache->lock); | |
7910 | spin_lock_init(&cache->tree_lock); | |
7911 | cache->fs_info = info; | |
7912 | INIT_LIST_HEAD(&cache->list); | |
7913 | INIT_LIST_HEAD(&cache->cluster_list); | |
7914 | ||
7915 | /* | |
7916 | * we only want to have 32k of ram per block group for keeping | |
7917 | * track of free space, and if we pass 1/2 of that we want to | |
7918 | * start converting things over to using bitmaps | |
7919 | */ | |
7920 | cache->extents_thresh = ((1024 * 32) / 2) / | |
7921 | sizeof(struct btrfs_free_space); | |
7922 | ||
7923 | read_extent_buffer(leaf, &cache->item, | |
7924 | btrfs_item_ptr_offset(leaf, path->slots[0]), | |
7925 | sizeof(cache->item)); | |
7926 | memcpy(&cache->key, &found_key, sizeof(found_key)); | |
7927 | ||
7928 | key.objectid = found_key.objectid + found_key.offset; | |
7929 | btrfs_release_path(root, path); | |
7930 | cache->flags = btrfs_block_group_flags(&cache->item); | |
7931 | cache->sectorsize = root->sectorsize; | |
7932 | ||
7933 | /* | |
7934 | * check for two cases, either we are full, and therefore | |
7935 | * don't need to bother with the caching work since we won't | |
7936 | * find any space, or we are empty, and we can just add all | |
7937 | * the space in and be done with it. This saves us _alot_ of | |
7938 | * time, particularly in the full case. | |
7939 | */ | |
7940 | if (found_key.offset == btrfs_block_group_used(&cache->item)) { | |
7941 | exclude_super_stripes(root, cache); | |
7942 | cache->last_byte_to_unpin = (u64)-1; | |
7943 | cache->cached = BTRFS_CACHE_FINISHED; | |
7944 | free_excluded_extents(root, cache); | |
7945 | } else if (btrfs_block_group_used(&cache->item) == 0) { | |
7946 | exclude_super_stripes(root, cache); | |
7947 | cache->last_byte_to_unpin = (u64)-1; | |
7948 | cache->cached = BTRFS_CACHE_FINISHED; | |
7949 | add_new_free_space(cache, root->fs_info, | |
7950 | found_key.objectid, | |
7951 | found_key.objectid + | |
7952 | found_key.offset); | |
7953 | free_excluded_extents(root, cache); | |
7954 | } | |
7955 | ||
7956 | ret = update_space_info(info, cache->flags, found_key.offset, | |
7957 | btrfs_block_group_used(&cache->item), | |
7958 | &space_info); | |
7959 | BUG_ON(ret); | |
7960 | cache->space_info = space_info; | |
7961 | spin_lock(&cache->space_info->lock); | |
7962 | cache->space_info->bytes_readonly += cache->bytes_super; | |
7963 | spin_unlock(&cache->space_info->lock); | |
7964 | ||
7965 | __link_block_group(space_info, cache); | |
7966 | ||
7967 | ret = btrfs_add_block_group_cache(root->fs_info, cache); | |
7968 | BUG_ON(ret); | |
7969 | ||
7970 | set_avail_alloc_bits(root->fs_info, cache->flags); | |
7971 | if (btrfs_chunk_readonly(root, cache->key.objectid)) | |
7972 | set_block_group_ro(cache); | |
7973 | } | |
7974 | ||
7975 | list_for_each_entry_rcu(space_info, &root->fs_info->space_info, list) { | |
7976 | if (!(get_alloc_profile(root, space_info->flags) & | |
7977 | (BTRFS_BLOCK_GROUP_RAID10 | | |
7978 | BTRFS_BLOCK_GROUP_RAID1 | | |
7979 | BTRFS_BLOCK_GROUP_DUP))) | |
7980 | continue; | |
7981 | /* | |
7982 | * avoid allocating from un-mirrored block group if there are | |
7983 | * mirrored block groups. | |
7984 | */ | |
7985 | list_for_each_entry(cache, &space_info->block_groups[3], list) | |
7986 | set_block_group_ro(cache); | |
7987 | list_for_each_entry(cache, &space_info->block_groups[4], list) | |
7988 | set_block_group_ro(cache); | |
7989 | } | |
7990 | ||
7991 | init_global_block_rsv(info); | |
7992 | ret = 0; | |
7993 | error: | |
7994 | btrfs_free_path(path); | |
7995 | return ret; | |
7996 | } | |
7997 | ||
7998 | int btrfs_make_block_group(struct btrfs_trans_handle *trans, | |
7999 | struct btrfs_root *root, u64 bytes_used, | |
8000 | u64 type, u64 chunk_objectid, u64 chunk_offset, | |
8001 | u64 size) | |
8002 | { | |
8003 | int ret; | |
8004 | struct btrfs_root *extent_root; | |
8005 | struct btrfs_block_group_cache *cache; | |
8006 | ||
8007 | extent_root = root->fs_info->extent_root; | |
8008 | ||
8009 | root->fs_info->last_trans_log_full_commit = trans->transid; | |
8010 | ||
8011 | cache = kzalloc(sizeof(*cache), GFP_NOFS); | |
8012 | if (!cache) | |
8013 | return -ENOMEM; | |
8014 | ||
8015 | cache->key.objectid = chunk_offset; | |
8016 | cache->key.offset = size; | |
8017 | cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY; | |
8018 | cache->sectorsize = root->sectorsize; | |
8019 | ||
8020 | /* | |
8021 | * we only want to have 32k of ram per block group for keeping track | |
8022 | * of free space, and if we pass 1/2 of that we want to start | |
8023 | * converting things over to using bitmaps | |
8024 | */ | |
8025 | cache->extents_thresh = ((1024 * 32) / 2) / | |
8026 | sizeof(struct btrfs_free_space); | |
8027 | atomic_set(&cache->count, 1); | |
8028 | spin_lock_init(&cache->lock); | |
8029 | spin_lock_init(&cache->tree_lock); | |
8030 | INIT_LIST_HEAD(&cache->list); | |
8031 | INIT_LIST_HEAD(&cache->cluster_list); | |
8032 | ||
8033 | btrfs_set_block_group_used(&cache->item, bytes_used); | |
8034 | btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid); | |
8035 | cache->flags = type; | |
8036 | btrfs_set_block_group_flags(&cache->item, type); | |
8037 | ||
8038 | cache->last_byte_to_unpin = (u64)-1; | |
8039 | cache->cached = BTRFS_CACHE_FINISHED; | |
8040 | exclude_super_stripes(root, cache); | |
8041 | ||
8042 | add_new_free_space(cache, root->fs_info, chunk_offset, | |
8043 | chunk_offset + size); | |
8044 | ||
8045 | free_excluded_extents(root, cache); | |
8046 | ||
8047 | ret = update_space_info(root->fs_info, cache->flags, size, bytes_used, | |
8048 | &cache->space_info); | |
8049 | BUG_ON(ret); | |
8050 | ||
8051 | spin_lock(&cache->space_info->lock); | |
8052 | cache->space_info->bytes_readonly += cache->bytes_super; | |
8053 | spin_unlock(&cache->space_info->lock); | |
8054 | ||
8055 | __link_block_group(cache->space_info, cache); | |
8056 | ||
8057 | ret = btrfs_add_block_group_cache(root->fs_info, cache); | |
8058 | BUG_ON(ret); | |
8059 | ||
8060 | ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item, | |
8061 | sizeof(cache->item)); | |
8062 | BUG_ON(ret); | |
8063 | ||
8064 | set_avail_alloc_bits(extent_root->fs_info, type); | |
8065 | ||
8066 | return 0; | |
8067 | } | |
8068 | ||
8069 | int btrfs_remove_block_group(struct btrfs_trans_handle *trans, | |
8070 | struct btrfs_root *root, u64 group_start) | |
8071 | { | |
8072 | struct btrfs_path *path; | |
8073 | struct btrfs_block_group_cache *block_group; | |
8074 | struct btrfs_free_cluster *cluster; | |
8075 | struct btrfs_key key; | |
8076 | int ret; | |
8077 | ||
8078 | root = root->fs_info->extent_root; | |
8079 | ||
8080 | block_group = btrfs_lookup_block_group(root->fs_info, group_start); | |
8081 | BUG_ON(!block_group); | |
8082 | BUG_ON(!block_group->ro); | |
8083 | ||
8084 | memcpy(&key, &block_group->key, sizeof(key)); | |
8085 | ||
8086 | /* make sure this block group isn't part of an allocation cluster */ | |
8087 | cluster = &root->fs_info->data_alloc_cluster; | |
8088 | spin_lock(&cluster->refill_lock); | |
8089 | btrfs_return_cluster_to_free_space(block_group, cluster); | |
8090 | spin_unlock(&cluster->refill_lock); | |
8091 | ||
8092 | /* | |
8093 | * make sure this block group isn't part of a metadata | |
8094 | * allocation cluster | |
8095 | */ | |
8096 | cluster = &root->fs_info->meta_alloc_cluster; | |
8097 | spin_lock(&cluster->refill_lock); | |
8098 | btrfs_return_cluster_to_free_space(block_group, cluster); | |
8099 | spin_unlock(&cluster->refill_lock); | |
8100 | ||
8101 | path = btrfs_alloc_path(); | |
8102 | BUG_ON(!path); | |
8103 | ||
8104 | spin_lock(&root->fs_info->block_group_cache_lock); | |
8105 | rb_erase(&block_group->cache_node, | |
8106 | &root->fs_info->block_group_cache_tree); | |
8107 | spin_unlock(&root->fs_info->block_group_cache_lock); | |
8108 | ||
8109 | down_write(&block_group->space_info->groups_sem); | |
8110 | /* | |
8111 | * we must use list_del_init so people can check to see if they | |
8112 | * are still on the list after taking the semaphore | |
8113 | */ | |
8114 | list_del_init(&block_group->list); | |
8115 | up_write(&block_group->space_info->groups_sem); | |
8116 | ||
8117 | if (block_group->cached == BTRFS_CACHE_STARTED) | |
8118 | wait_block_group_cache_done(block_group); | |
8119 | ||
8120 | btrfs_remove_free_space_cache(block_group); | |
8121 | ||
8122 | spin_lock(&block_group->space_info->lock); | |
8123 | block_group->space_info->total_bytes -= block_group->key.offset; | |
8124 | block_group->space_info->bytes_readonly -= block_group->key.offset; | |
8125 | spin_unlock(&block_group->space_info->lock); | |
8126 | ||
8127 | btrfs_clear_space_info_full(root->fs_info); | |
8128 | ||
8129 | btrfs_put_block_group(block_group); | |
8130 | btrfs_put_block_group(block_group); | |
8131 | ||
8132 | ret = btrfs_search_slot(trans, root, &key, path, -1, 1); | |
8133 | if (ret > 0) | |
8134 | ret = -EIO; | |
8135 | if (ret < 0) | |
8136 | goto out; | |
8137 | ||
8138 | ret = btrfs_del_item(trans, root, path); | |
8139 | out: | |
8140 | btrfs_free_path(path); | |
8141 | return ret; | |
8142 | } |