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56bec294 CM |
1 | /* |
2 | * Copyright (C) 2009 Oracle. All rights reserved. | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or | |
5 | * modify it under the terms of the GNU General Public | |
6 | * License v2 as published by the Free Software Foundation. | |
7 | * | |
8 | * This program is distributed in the hope that it will be useful, | |
9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
11 | * General Public License for more details. | |
12 | * | |
13 | * You should have received a copy of the GNU General Public | |
14 | * License along with this program; if not, write to the | |
15 | * Free Software Foundation, Inc., 59 Temple Place - Suite 330, | |
16 | * Boston, MA 021110-1307, USA. | |
17 | */ | |
18 | ||
19 | #include <linux/sched.h> | |
5a0e3ad6 | 20 | #include <linux/slab.h> |
56bec294 | 21 | #include <linux/sort.h> |
56bec294 CM |
22 | #include "ctree.h" |
23 | #include "delayed-ref.h" | |
24 | #include "transaction.h" | |
25 | ||
78a6184a MX |
26 | struct kmem_cache *btrfs_delayed_ref_head_cachep; |
27 | struct kmem_cache *btrfs_delayed_tree_ref_cachep; | |
28 | struct kmem_cache *btrfs_delayed_data_ref_cachep; | |
29 | struct kmem_cache *btrfs_delayed_extent_op_cachep; | |
56bec294 CM |
30 | /* |
31 | * delayed back reference update tracking. For subvolume trees | |
32 | * we queue up extent allocations and backref maintenance for | |
33 | * delayed processing. This avoids deep call chains where we | |
34 | * add extents in the middle of btrfs_search_slot, and it allows | |
35 | * us to buffer up frequently modified backrefs in an rb tree instead | |
36 | * of hammering updates on the extent allocation tree. | |
56bec294 CM |
37 | */ |
38 | ||
39 | /* | |
5d4f98a2 YZ |
40 | * compare two delayed tree backrefs with same bytenr and type |
41 | */ | |
42 | static int comp_tree_refs(struct btrfs_delayed_tree_ref *ref2, | |
43 | struct btrfs_delayed_tree_ref *ref1) | |
44 | { | |
ae1e206b JB |
45 | if (ref1->root < ref2->root) |
46 | return -1; | |
47 | if (ref1->root > ref2->root) | |
48 | return 1; | |
49 | if (ref1->parent < ref2->parent) | |
50 | return -1; | |
51 | if (ref1->parent > ref2->parent) | |
52 | return 1; | |
5d4f98a2 YZ |
53 | return 0; |
54 | } | |
55 | ||
56 | /* | |
57 | * compare two delayed data backrefs with same bytenr and type | |
56bec294 | 58 | */ |
5d4f98a2 YZ |
59 | static int comp_data_refs(struct btrfs_delayed_data_ref *ref2, |
60 | struct btrfs_delayed_data_ref *ref1) | |
56bec294 | 61 | { |
5d4f98a2 YZ |
62 | if (ref1->node.type == BTRFS_EXTENT_DATA_REF_KEY) { |
63 | if (ref1->root < ref2->root) | |
64 | return -1; | |
65 | if (ref1->root > ref2->root) | |
66 | return 1; | |
67 | if (ref1->objectid < ref2->objectid) | |
68 | return -1; | |
69 | if (ref1->objectid > ref2->objectid) | |
70 | return 1; | |
71 | if (ref1->offset < ref2->offset) | |
72 | return -1; | |
73 | if (ref1->offset > ref2->offset) | |
74 | return 1; | |
75 | } else { | |
76 | if (ref1->parent < ref2->parent) | |
77 | return -1; | |
78 | if (ref1->parent > ref2->parent) | |
79 | return 1; | |
80 | } | |
81 | return 0; | |
82 | } | |
83 | ||
84 | /* | |
85 | * entries in the rb tree are ordered by the byte number of the extent, | |
86 | * type of the delayed backrefs and content of delayed backrefs. | |
87 | */ | |
88 | static int comp_entry(struct btrfs_delayed_ref_node *ref2, | |
ae1e206b JB |
89 | struct btrfs_delayed_ref_node *ref1, |
90 | bool compare_seq) | |
5d4f98a2 YZ |
91 | { |
92 | if (ref1->bytenr < ref2->bytenr) | |
56bec294 | 93 | return -1; |
5d4f98a2 | 94 | if (ref1->bytenr > ref2->bytenr) |
56bec294 | 95 | return 1; |
5d4f98a2 YZ |
96 | if (ref1->is_head && ref2->is_head) |
97 | return 0; | |
98 | if (ref2->is_head) | |
56bec294 | 99 | return -1; |
5d4f98a2 | 100 | if (ref1->is_head) |
56bec294 | 101 | return 1; |
5d4f98a2 YZ |
102 | if (ref1->type < ref2->type) |
103 | return -1; | |
104 | if (ref1->type > ref2->type) | |
105 | return 1; | |
00f04b88 | 106 | /* merging of sequenced refs is not allowed */ |
ae1e206b JB |
107 | if (compare_seq) { |
108 | if (ref1->seq < ref2->seq) | |
109 | return -1; | |
110 | if (ref1->seq > ref2->seq) | |
111 | return 1; | |
112 | } | |
5d4f98a2 YZ |
113 | if (ref1->type == BTRFS_TREE_BLOCK_REF_KEY || |
114 | ref1->type == BTRFS_SHARED_BLOCK_REF_KEY) { | |
115 | return comp_tree_refs(btrfs_delayed_node_to_tree_ref(ref2), | |
116 | btrfs_delayed_node_to_tree_ref(ref1)); | |
117 | } else if (ref1->type == BTRFS_EXTENT_DATA_REF_KEY || | |
118 | ref1->type == BTRFS_SHARED_DATA_REF_KEY) { | |
119 | return comp_data_refs(btrfs_delayed_node_to_data_ref(ref2), | |
120 | btrfs_delayed_node_to_data_ref(ref1)); | |
121 | } | |
122 | BUG(); | |
56bec294 CM |
123 | return 0; |
124 | } | |
125 | ||
126 | /* | |
127 | * insert a new ref into the rbtree. This returns any existing refs | |
128 | * for the same (bytenr,parent) tuple, or NULL if the new node was properly | |
129 | * inserted. | |
130 | */ | |
131 | static struct btrfs_delayed_ref_node *tree_insert(struct rb_root *root, | |
56bec294 CM |
132 | struct rb_node *node) |
133 | { | |
134 | struct rb_node **p = &root->rb_node; | |
135 | struct rb_node *parent_node = NULL; | |
136 | struct btrfs_delayed_ref_node *entry; | |
5d4f98a2 | 137 | struct btrfs_delayed_ref_node *ins; |
56bec294 CM |
138 | int cmp; |
139 | ||
5d4f98a2 | 140 | ins = rb_entry(node, struct btrfs_delayed_ref_node, rb_node); |
56bec294 CM |
141 | while (*p) { |
142 | parent_node = *p; | |
143 | entry = rb_entry(parent_node, struct btrfs_delayed_ref_node, | |
144 | rb_node); | |
145 | ||
ae1e206b | 146 | cmp = comp_entry(entry, ins, 1); |
56bec294 CM |
147 | if (cmp < 0) |
148 | p = &(*p)->rb_left; | |
149 | else if (cmp > 0) | |
150 | p = &(*p)->rb_right; | |
151 | else | |
152 | return entry; | |
153 | } | |
154 | ||
56bec294 CM |
155 | rb_link_node(node, parent_node, p); |
156 | rb_insert_color(node, root); | |
157 | return NULL; | |
158 | } | |
159 | ||
160 | /* | |
5d4f98a2 | 161 | * find an head entry based on bytenr. This returns the delayed ref |
d1270cd9 AJ |
162 | * head if it was able to find one, or NULL if nothing was in that spot. |
163 | * If return_bigger is given, the next bigger entry is returned if no exact | |
164 | * match is found. | |
56bec294 | 165 | */ |
5d4f98a2 YZ |
166 | static struct btrfs_delayed_ref_node *find_ref_head(struct rb_root *root, |
167 | u64 bytenr, | |
d1270cd9 AJ |
168 | struct btrfs_delayed_ref_node **last, |
169 | int return_bigger) | |
56bec294 | 170 | { |
d1270cd9 | 171 | struct rb_node *n; |
56bec294 | 172 | struct btrfs_delayed_ref_node *entry; |
d1270cd9 | 173 | int cmp = 0; |
56bec294 | 174 | |
d1270cd9 AJ |
175 | again: |
176 | n = root->rb_node; | |
177 | entry = NULL; | |
56bec294 CM |
178 | while (n) { |
179 | entry = rb_entry(n, struct btrfs_delayed_ref_node, rb_node); | |
180 | WARN_ON(!entry->in_tree); | |
c3e69d58 CM |
181 | if (last) |
182 | *last = entry; | |
56bec294 | 183 | |
5d4f98a2 YZ |
184 | if (bytenr < entry->bytenr) |
185 | cmp = -1; | |
186 | else if (bytenr > entry->bytenr) | |
187 | cmp = 1; | |
188 | else if (!btrfs_delayed_ref_is_head(entry)) | |
189 | cmp = 1; | |
190 | else | |
191 | cmp = 0; | |
192 | ||
56bec294 CM |
193 | if (cmp < 0) |
194 | n = n->rb_left; | |
195 | else if (cmp > 0) | |
196 | n = n->rb_right; | |
197 | else | |
198 | return entry; | |
199 | } | |
d1270cd9 AJ |
200 | if (entry && return_bigger) { |
201 | if (cmp > 0) { | |
202 | n = rb_next(&entry->rb_node); | |
203 | if (!n) | |
204 | n = rb_first(root); | |
205 | entry = rb_entry(n, struct btrfs_delayed_ref_node, | |
206 | rb_node); | |
207 | bytenr = entry->bytenr; | |
208 | return_bigger = 0; | |
209 | goto again; | |
210 | } | |
211 | return entry; | |
212 | } | |
56bec294 CM |
213 | return NULL; |
214 | } | |
215 | ||
c3e69d58 CM |
216 | int btrfs_delayed_ref_lock(struct btrfs_trans_handle *trans, |
217 | struct btrfs_delayed_ref_head *head) | |
56bec294 | 218 | { |
c3e69d58 CM |
219 | struct btrfs_delayed_ref_root *delayed_refs; |
220 | ||
221 | delayed_refs = &trans->transaction->delayed_refs; | |
222 | assert_spin_locked(&delayed_refs->lock); | |
223 | if (mutex_trylock(&head->mutex)) | |
224 | return 0; | |
225 | ||
226 | atomic_inc(&head->node.refs); | |
227 | spin_unlock(&delayed_refs->lock); | |
228 | ||
229 | mutex_lock(&head->mutex); | |
230 | spin_lock(&delayed_refs->lock); | |
231 | if (!head->node.in_tree) { | |
232 | mutex_unlock(&head->mutex); | |
233 | btrfs_put_delayed_ref(&head->node); | |
234 | return -EAGAIN; | |
235 | } | |
236 | btrfs_put_delayed_ref(&head->node); | |
237 | return 0; | |
238 | } | |
239 | ||
ae1e206b JB |
240 | static void inline drop_delayed_ref(struct btrfs_trans_handle *trans, |
241 | struct btrfs_delayed_ref_root *delayed_refs, | |
242 | struct btrfs_delayed_ref_node *ref) | |
243 | { | |
244 | rb_erase(&ref->rb_node, &delayed_refs->root); | |
245 | ref->in_tree = 0; | |
246 | btrfs_put_delayed_ref(ref); | |
247 | delayed_refs->num_entries--; | |
248 | if (trans->delayed_ref_updates) | |
249 | trans->delayed_ref_updates--; | |
250 | } | |
251 | ||
252 | static int merge_ref(struct btrfs_trans_handle *trans, | |
253 | struct btrfs_delayed_ref_root *delayed_refs, | |
254 | struct btrfs_delayed_ref_node *ref, u64 seq) | |
255 | { | |
256 | struct rb_node *node; | |
257 | int merged = 0; | |
258 | int mod = 0; | |
259 | int done = 0; | |
260 | ||
261 | node = rb_prev(&ref->rb_node); | |
262 | while (node) { | |
263 | struct btrfs_delayed_ref_node *next; | |
264 | ||
265 | next = rb_entry(node, struct btrfs_delayed_ref_node, rb_node); | |
266 | node = rb_prev(node); | |
267 | if (next->bytenr != ref->bytenr) | |
268 | break; | |
269 | if (seq && next->seq >= seq) | |
270 | break; | |
271 | if (comp_entry(ref, next, 0)) | |
272 | continue; | |
273 | ||
274 | if (ref->action == next->action) { | |
275 | mod = next->ref_mod; | |
276 | } else { | |
277 | if (ref->ref_mod < next->ref_mod) { | |
278 | struct btrfs_delayed_ref_node *tmp; | |
279 | ||
280 | tmp = ref; | |
281 | ref = next; | |
282 | next = tmp; | |
283 | done = 1; | |
284 | } | |
285 | mod = -next->ref_mod; | |
286 | } | |
287 | ||
288 | merged++; | |
289 | drop_delayed_ref(trans, delayed_refs, next); | |
290 | ref->ref_mod += mod; | |
291 | if (ref->ref_mod == 0) { | |
292 | drop_delayed_ref(trans, delayed_refs, ref); | |
293 | break; | |
294 | } else { | |
295 | /* | |
296 | * You can't have multiples of the same ref on a tree | |
297 | * block. | |
298 | */ | |
299 | WARN_ON(ref->type == BTRFS_TREE_BLOCK_REF_KEY || | |
300 | ref->type == BTRFS_SHARED_BLOCK_REF_KEY); | |
301 | } | |
302 | ||
303 | if (done) | |
304 | break; | |
305 | node = rb_prev(&ref->rb_node); | |
306 | } | |
307 | ||
308 | return merged; | |
309 | } | |
310 | ||
311 | void btrfs_merge_delayed_refs(struct btrfs_trans_handle *trans, | |
312 | struct btrfs_fs_info *fs_info, | |
313 | struct btrfs_delayed_ref_root *delayed_refs, | |
314 | struct btrfs_delayed_ref_head *head) | |
315 | { | |
316 | struct rb_node *node; | |
317 | u64 seq = 0; | |
318 | ||
319 | spin_lock(&fs_info->tree_mod_seq_lock); | |
320 | if (!list_empty(&fs_info->tree_mod_seq_list)) { | |
321 | struct seq_list *elem; | |
322 | ||
323 | elem = list_first_entry(&fs_info->tree_mod_seq_list, | |
324 | struct seq_list, list); | |
325 | seq = elem->seq; | |
326 | } | |
327 | spin_unlock(&fs_info->tree_mod_seq_lock); | |
328 | ||
329 | node = rb_prev(&head->node.rb_node); | |
330 | while (node) { | |
331 | struct btrfs_delayed_ref_node *ref; | |
332 | ||
333 | ref = rb_entry(node, struct btrfs_delayed_ref_node, | |
334 | rb_node); | |
335 | if (ref->bytenr != head->node.bytenr) | |
336 | break; | |
337 | ||
338 | /* We can't merge refs that are outside of our seq count */ | |
339 | if (seq && ref->seq >= seq) | |
340 | break; | |
341 | if (merge_ref(trans, delayed_refs, ref, seq)) | |
342 | node = rb_prev(&head->node.rb_node); | |
343 | else | |
344 | node = rb_prev(node); | |
345 | } | |
346 | } | |
347 | ||
097b8a7c JS |
348 | int btrfs_check_delayed_seq(struct btrfs_fs_info *fs_info, |
349 | struct btrfs_delayed_ref_root *delayed_refs, | |
00f04b88 AJ |
350 | u64 seq) |
351 | { | |
352 | struct seq_list *elem; | |
097b8a7c JS |
353 | int ret = 0; |
354 | ||
355 | spin_lock(&fs_info->tree_mod_seq_lock); | |
356 | if (!list_empty(&fs_info->tree_mod_seq_list)) { | |
357 | elem = list_first_entry(&fs_info->tree_mod_seq_list, | |
358 | struct seq_list, list); | |
359 | if (seq >= elem->seq) { | |
360 | pr_debug("holding back delayed_ref %llu, lowest is " | |
361 | "%llu (%p)\n", seq, elem->seq, delayed_refs); | |
362 | ret = 1; | |
363 | } | |
00f04b88 | 364 | } |
097b8a7c JS |
365 | |
366 | spin_unlock(&fs_info->tree_mod_seq_lock); | |
367 | return ret; | |
00f04b88 AJ |
368 | } |
369 | ||
c3e69d58 CM |
370 | int btrfs_find_ref_cluster(struct btrfs_trans_handle *trans, |
371 | struct list_head *cluster, u64 start) | |
372 | { | |
373 | int count = 0; | |
374 | struct btrfs_delayed_ref_root *delayed_refs; | |
56bec294 | 375 | struct rb_node *node; |
c3e69d58 | 376 | struct btrfs_delayed_ref_node *ref; |
56bec294 | 377 | struct btrfs_delayed_ref_head *head; |
56bec294 | 378 | |
c3e69d58 CM |
379 | delayed_refs = &trans->transaction->delayed_refs; |
380 | if (start == 0) { | |
381 | node = rb_first(&delayed_refs->root); | |
382 | } else { | |
383 | ref = NULL; | |
d1270cd9 | 384 | find_ref_head(&delayed_refs->root, start + 1, &ref, 1); |
c3e69d58 | 385 | if (ref) { |
c3e69d58 CM |
386 | node = &ref->rb_node; |
387 | } else | |
388 | node = rb_first(&delayed_refs->root); | |
389 | } | |
390 | again: | |
391 | while (node && count < 32) { | |
392 | ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node); | |
56bec294 CM |
393 | if (btrfs_delayed_ref_is_head(ref)) { |
394 | head = btrfs_delayed_node_to_head(ref); | |
c3e69d58 CM |
395 | if (list_empty(&head->cluster)) { |
396 | list_add_tail(&head->cluster, cluster); | |
397 | delayed_refs->run_delayed_start = | |
398 | head->node.bytenr; | |
399 | count++; | |
400 | ||
401 | WARN_ON(delayed_refs->num_heads_ready == 0); | |
402 | delayed_refs->num_heads_ready--; | |
403 | } else if (count) { | |
404 | /* the goal of the clustering is to find extents | |
405 | * that are likely to end up in the same extent | |
406 | * leaf on disk. So, we don't want them spread | |
407 | * all over the tree. Stop now if we've hit | |
408 | * a head that was already in use | |
409 | */ | |
56bec294 CM |
410 | break; |
411 | } | |
412 | } | |
c3e69d58 | 413 | node = rb_next(node); |
56bec294 | 414 | } |
c3e69d58 CM |
415 | if (count) { |
416 | return 0; | |
417 | } else if (start) { | |
418 | /* | |
419 | * we've gone to the end of the rbtree without finding any | |
420 | * clusters. start from the beginning and try again | |
421 | */ | |
422 | start = 0; | |
423 | node = rb_first(&delayed_refs->root); | |
424 | goto again; | |
425 | } | |
426 | return 1; | |
56bec294 CM |
427 | } |
428 | ||
093486c4 MX |
429 | void btrfs_release_ref_cluster(struct list_head *cluster) |
430 | { | |
431 | struct list_head *pos, *q; | |
432 | ||
433 | list_for_each_safe(pos, q, cluster) | |
434 | list_del_init(pos); | |
435 | } | |
436 | ||
56bec294 CM |
437 | /* |
438 | * helper function to update an extent delayed ref in the | |
439 | * rbtree. existing and update must both have the same | |
440 | * bytenr and parent | |
441 | * | |
442 | * This may free existing if the update cancels out whatever | |
443 | * operation it was doing. | |
444 | */ | |
445 | static noinline void | |
446 | update_existing_ref(struct btrfs_trans_handle *trans, | |
447 | struct btrfs_delayed_ref_root *delayed_refs, | |
448 | struct btrfs_delayed_ref_node *existing, | |
449 | struct btrfs_delayed_ref_node *update) | |
450 | { | |
5d4f98a2 | 451 | if (update->action != existing->action) { |
56bec294 CM |
452 | /* |
453 | * this is effectively undoing either an add or a | |
454 | * drop. We decrement the ref_mod, and if it goes | |
455 | * down to zero we just delete the entry without | |
456 | * every changing the extent allocation tree. | |
457 | */ | |
458 | existing->ref_mod--; | |
ae1e206b JB |
459 | if (existing->ref_mod == 0) |
460 | drop_delayed_ref(trans, delayed_refs, existing); | |
461 | else | |
5d4f98a2 YZ |
462 | WARN_ON(existing->type == BTRFS_TREE_BLOCK_REF_KEY || |
463 | existing->type == BTRFS_SHARED_BLOCK_REF_KEY); | |
56bec294 | 464 | } else { |
5d4f98a2 YZ |
465 | WARN_ON(existing->type == BTRFS_TREE_BLOCK_REF_KEY || |
466 | existing->type == BTRFS_SHARED_BLOCK_REF_KEY); | |
56bec294 CM |
467 | /* |
468 | * the action on the existing ref matches | |
469 | * the action on the ref we're trying to add. | |
470 | * Bump the ref_mod by one so the backref that | |
471 | * is eventually added/removed has the correct | |
472 | * reference count | |
473 | */ | |
474 | existing->ref_mod += update->ref_mod; | |
475 | } | |
476 | } | |
477 | ||
478 | /* | |
479 | * helper function to update the accounting in the head ref | |
480 | * existing and update must have the same bytenr | |
481 | */ | |
482 | static noinline void | |
483 | update_existing_head_ref(struct btrfs_delayed_ref_node *existing, | |
484 | struct btrfs_delayed_ref_node *update) | |
485 | { | |
486 | struct btrfs_delayed_ref_head *existing_ref; | |
487 | struct btrfs_delayed_ref_head *ref; | |
488 | ||
489 | existing_ref = btrfs_delayed_node_to_head(existing); | |
490 | ref = btrfs_delayed_node_to_head(update); | |
5d4f98a2 | 491 | BUG_ON(existing_ref->is_data != ref->is_data); |
56bec294 CM |
492 | |
493 | if (ref->must_insert_reserved) { | |
494 | /* if the extent was freed and then | |
495 | * reallocated before the delayed ref | |
496 | * entries were processed, we can end up | |
497 | * with an existing head ref without | |
498 | * the must_insert_reserved flag set. | |
499 | * Set it again here | |
500 | */ | |
501 | existing_ref->must_insert_reserved = ref->must_insert_reserved; | |
502 | ||
503 | /* | |
504 | * update the num_bytes so we make sure the accounting | |
505 | * is done correctly | |
506 | */ | |
507 | existing->num_bytes = update->num_bytes; | |
508 | ||
509 | } | |
510 | ||
5d4f98a2 YZ |
511 | if (ref->extent_op) { |
512 | if (!existing_ref->extent_op) { | |
513 | existing_ref->extent_op = ref->extent_op; | |
514 | } else { | |
515 | if (ref->extent_op->update_key) { | |
516 | memcpy(&existing_ref->extent_op->key, | |
517 | &ref->extent_op->key, | |
518 | sizeof(ref->extent_op->key)); | |
519 | existing_ref->extent_op->update_key = 1; | |
520 | } | |
521 | if (ref->extent_op->update_flags) { | |
522 | existing_ref->extent_op->flags_to_set |= | |
523 | ref->extent_op->flags_to_set; | |
524 | existing_ref->extent_op->update_flags = 1; | |
525 | } | |
78a6184a | 526 | btrfs_free_delayed_extent_op(ref->extent_op); |
5d4f98a2 YZ |
527 | } |
528 | } | |
56bec294 CM |
529 | /* |
530 | * update the reference mod on the head to reflect this new operation | |
531 | */ | |
532 | existing->ref_mod += update->ref_mod; | |
533 | } | |
534 | ||
535 | /* | |
5d4f98a2 | 536 | * helper function to actually insert a head node into the rbtree. |
56bec294 | 537 | * this does all the dirty work in terms of maintaining the correct |
5d4f98a2 | 538 | * overall modification count. |
56bec294 | 539 | */ |
143bede5 | 540 | static noinline void add_delayed_ref_head(struct btrfs_fs_info *fs_info, |
66d7e7f0 | 541 | struct btrfs_trans_handle *trans, |
5d4f98a2 YZ |
542 | struct btrfs_delayed_ref_node *ref, |
543 | u64 bytenr, u64 num_bytes, | |
544 | int action, int is_data) | |
56bec294 CM |
545 | { |
546 | struct btrfs_delayed_ref_node *existing; | |
c3e69d58 | 547 | struct btrfs_delayed_ref_head *head_ref = NULL; |
56bec294 CM |
548 | struct btrfs_delayed_ref_root *delayed_refs; |
549 | int count_mod = 1; | |
550 | int must_insert_reserved = 0; | |
551 | ||
552 | /* | |
553 | * the head node stores the sum of all the mods, so dropping a ref | |
554 | * should drop the sum in the head node by one. | |
555 | */ | |
5d4f98a2 YZ |
556 | if (action == BTRFS_UPDATE_DELAYED_HEAD) |
557 | count_mod = 0; | |
558 | else if (action == BTRFS_DROP_DELAYED_REF) | |
559 | count_mod = -1; | |
56bec294 CM |
560 | |
561 | /* | |
562 | * BTRFS_ADD_DELAYED_EXTENT means that we need to update | |
563 | * the reserved accounting when the extent is finally added, or | |
564 | * if a later modification deletes the delayed ref without ever | |
565 | * inserting the extent into the extent allocation tree. | |
566 | * ref->must_insert_reserved is the flag used to record | |
567 | * that accounting mods are required. | |
568 | * | |
569 | * Once we record must_insert_reserved, switch the action to | |
570 | * BTRFS_ADD_DELAYED_REF because other special casing is not required. | |
571 | */ | |
5d4f98a2 | 572 | if (action == BTRFS_ADD_DELAYED_EXTENT) |
56bec294 | 573 | must_insert_reserved = 1; |
5d4f98a2 | 574 | else |
56bec294 | 575 | must_insert_reserved = 0; |
56bec294 CM |
576 | |
577 | delayed_refs = &trans->transaction->delayed_refs; | |
578 | ||
579 | /* first set the basic ref node struct up */ | |
580 | atomic_set(&ref->refs, 1); | |
581 | ref->bytenr = bytenr; | |
5d4f98a2 | 582 | ref->num_bytes = num_bytes; |
56bec294 | 583 | ref->ref_mod = count_mod; |
5d4f98a2 YZ |
584 | ref->type = 0; |
585 | ref->action = 0; | |
586 | ref->is_head = 1; | |
56bec294 | 587 | ref->in_tree = 1; |
00f04b88 | 588 | ref->seq = 0; |
5d4f98a2 YZ |
589 | |
590 | head_ref = btrfs_delayed_node_to_head(ref); | |
591 | head_ref->must_insert_reserved = must_insert_reserved; | |
592 | head_ref->is_data = is_data; | |
593 | ||
594 | INIT_LIST_HEAD(&head_ref->cluster); | |
595 | mutex_init(&head_ref->mutex); | |
596 | ||
1abe9b8a | 597 | trace_btrfs_delayed_ref_head(ref, head_ref, action); |
598 | ||
5d4f98a2 YZ |
599 | existing = tree_insert(&delayed_refs->root, &ref->rb_node); |
600 | ||
601 | if (existing) { | |
602 | update_existing_head_ref(existing, ref); | |
603 | /* | |
604 | * we've updated the existing ref, free the newly | |
605 | * allocated ref | |
606 | */ | |
78a6184a | 607 | kmem_cache_free(btrfs_delayed_ref_head_cachep, head_ref); |
5d4f98a2 YZ |
608 | } else { |
609 | delayed_refs->num_heads++; | |
610 | delayed_refs->num_heads_ready++; | |
611 | delayed_refs->num_entries++; | |
612 | trans->delayed_ref_updates++; | |
613 | } | |
5d4f98a2 YZ |
614 | } |
615 | ||
616 | /* | |
617 | * helper to insert a delayed tree ref into the rbtree. | |
618 | */ | |
143bede5 | 619 | static noinline void add_delayed_tree_ref(struct btrfs_fs_info *fs_info, |
66d7e7f0 | 620 | struct btrfs_trans_handle *trans, |
5d4f98a2 YZ |
621 | struct btrfs_delayed_ref_node *ref, |
622 | u64 bytenr, u64 num_bytes, u64 parent, | |
66d7e7f0 AJ |
623 | u64 ref_root, int level, int action, |
624 | int for_cow) | |
5d4f98a2 YZ |
625 | { |
626 | struct btrfs_delayed_ref_node *existing; | |
627 | struct btrfs_delayed_tree_ref *full_ref; | |
628 | struct btrfs_delayed_ref_root *delayed_refs; | |
00f04b88 | 629 | u64 seq = 0; |
5d4f98a2 YZ |
630 | |
631 | if (action == BTRFS_ADD_DELAYED_EXTENT) | |
632 | action = BTRFS_ADD_DELAYED_REF; | |
633 | ||
634 | delayed_refs = &trans->transaction->delayed_refs; | |
635 | ||
636 | /* first set the basic ref node struct up */ | |
637 | atomic_set(&ref->refs, 1); | |
638 | ref->bytenr = bytenr; | |
56bec294 | 639 | ref->num_bytes = num_bytes; |
5d4f98a2 YZ |
640 | ref->ref_mod = 1; |
641 | ref->action = action; | |
642 | ref->is_head = 0; | |
643 | ref->in_tree = 1; | |
56bec294 | 644 | |
546adb0d JS |
645 | if (need_ref_seq(for_cow, ref_root)) |
646 | seq = btrfs_get_tree_mod_seq(fs_info, &trans->delayed_ref_elem); | |
00f04b88 AJ |
647 | ref->seq = seq; |
648 | ||
5d4f98a2 | 649 | full_ref = btrfs_delayed_node_to_tree_ref(ref); |
eebe063b AJ |
650 | full_ref->parent = parent; |
651 | full_ref->root = ref_root; | |
652 | if (parent) | |
5d4f98a2 | 653 | ref->type = BTRFS_SHARED_BLOCK_REF_KEY; |
eebe063b | 654 | else |
5d4f98a2 | 655 | ref->type = BTRFS_TREE_BLOCK_REF_KEY; |
5d4f98a2 | 656 | full_ref->level = level; |
56bec294 | 657 | |
1abe9b8a | 658 | trace_btrfs_delayed_tree_ref(ref, full_ref, action); |
659 | ||
5d4f98a2 | 660 | existing = tree_insert(&delayed_refs->root, &ref->rb_node); |
56bec294 CM |
661 | |
662 | if (existing) { | |
5d4f98a2 YZ |
663 | update_existing_ref(trans, delayed_refs, existing, ref); |
664 | /* | |
665 | * we've updated the existing ref, free the newly | |
666 | * allocated ref | |
667 | */ | |
78a6184a | 668 | kmem_cache_free(btrfs_delayed_tree_ref_cachep, full_ref); |
5d4f98a2 YZ |
669 | } else { |
670 | delayed_refs->num_entries++; | |
671 | trans->delayed_ref_updates++; | |
672 | } | |
5d4f98a2 YZ |
673 | } |
674 | ||
675 | /* | |
676 | * helper to insert a delayed data ref into the rbtree. | |
677 | */ | |
143bede5 | 678 | static noinline void add_delayed_data_ref(struct btrfs_fs_info *fs_info, |
66d7e7f0 | 679 | struct btrfs_trans_handle *trans, |
5d4f98a2 YZ |
680 | struct btrfs_delayed_ref_node *ref, |
681 | u64 bytenr, u64 num_bytes, u64 parent, | |
682 | u64 ref_root, u64 owner, u64 offset, | |
66d7e7f0 | 683 | int action, int for_cow) |
5d4f98a2 YZ |
684 | { |
685 | struct btrfs_delayed_ref_node *existing; | |
686 | struct btrfs_delayed_data_ref *full_ref; | |
687 | struct btrfs_delayed_ref_root *delayed_refs; | |
00f04b88 | 688 | u64 seq = 0; |
5d4f98a2 YZ |
689 | |
690 | if (action == BTRFS_ADD_DELAYED_EXTENT) | |
691 | action = BTRFS_ADD_DELAYED_REF; | |
692 | ||
693 | delayed_refs = &trans->transaction->delayed_refs; | |
694 | ||
695 | /* first set the basic ref node struct up */ | |
696 | atomic_set(&ref->refs, 1); | |
697 | ref->bytenr = bytenr; | |
698 | ref->num_bytes = num_bytes; | |
699 | ref->ref_mod = 1; | |
700 | ref->action = action; | |
701 | ref->is_head = 0; | |
702 | ref->in_tree = 1; | |
703 | ||
546adb0d JS |
704 | if (need_ref_seq(for_cow, ref_root)) |
705 | seq = btrfs_get_tree_mod_seq(fs_info, &trans->delayed_ref_elem); | |
00f04b88 AJ |
706 | ref->seq = seq; |
707 | ||
5d4f98a2 | 708 | full_ref = btrfs_delayed_node_to_data_ref(ref); |
eebe063b AJ |
709 | full_ref->parent = parent; |
710 | full_ref->root = ref_root; | |
711 | if (parent) | |
5d4f98a2 | 712 | ref->type = BTRFS_SHARED_DATA_REF_KEY; |
eebe063b | 713 | else |
5d4f98a2 | 714 | ref->type = BTRFS_EXTENT_DATA_REF_KEY; |
66d7e7f0 | 715 | |
5d4f98a2 YZ |
716 | full_ref->objectid = owner; |
717 | full_ref->offset = offset; | |
56bec294 | 718 | |
1abe9b8a | 719 | trace_btrfs_delayed_data_ref(ref, full_ref, action); |
720 | ||
5d4f98a2 YZ |
721 | existing = tree_insert(&delayed_refs->root, &ref->rb_node); |
722 | ||
723 | if (existing) { | |
724 | update_existing_ref(trans, delayed_refs, existing, ref); | |
56bec294 CM |
725 | /* |
726 | * we've updated the existing ref, free the newly | |
727 | * allocated ref | |
728 | */ | |
78a6184a | 729 | kmem_cache_free(btrfs_delayed_data_ref_cachep, full_ref); |
56bec294 CM |
730 | } else { |
731 | delayed_refs->num_entries++; | |
732 | trans->delayed_ref_updates++; | |
733 | } | |
56bec294 CM |
734 | } |
735 | ||
736 | /* | |
5d4f98a2 | 737 | * add a delayed tree ref. This does all of the accounting required |
56bec294 CM |
738 | * to make sure the delayed ref is eventually processed before this |
739 | * transaction commits. | |
740 | */ | |
66d7e7f0 AJ |
741 | int btrfs_add_delayed_tree_ref(struct btrfs_fs_info *fs_info, |
742 | struct btrfs_trans_handle *trans, | |
5d4f98a2 YZ |
743 | u64 bytenr, u64 num_bytes, u64 parent, |
744 | u64 ref_root, int level, int action, | |
66d7e7f0 AJ |
745 | struct btrfs_delayed_extent_op *extent_op, |
746 | int for_cow) | |
56bec294 | 747 | { |
5d4f98a2 | 748 | struct btrfs_delayed_tree_ref *ref; |
56bec294 CM |
749 | struct btrfs_delayed_ref_head *head_ref; |
750 | struct btrfs_delayed_ref_root *delayed_refs; | |
56bec294 | 751 | |
5d4f98a2 | 752 | BUG_ON(extent_op && extent_op->is_data); |
78a6184a | 753 | ref = kmem_cache_alloc(btrfs_delayed_tree_ref_cachep, GFP_NOFS); |
56bec294 CM |
754 | if (!ref) |
755 | return -ENOMEM; | |
756 | ||
78a6184a | 757 | head_ref = kmem_cache_alloc(btrfs_delayed_ref_head_cachep, GFP_NOFS); |
5d4f98a2 | 758 | if (!head_ref) { |
78a6184a | 759 | kmem_cache_free(btrfs_delayed_tree_ref_cachep, ref); |
5d4f98a2 YZ |
760 | return -ENOMEM; |
761 | } | |
762 | ||
763 | head_ref->extent_op = extent_op; | |
764 | ||
765 | delayed_refs = &trans->transaction->delayed_refs; | |
766 | spin_lock(&delayed_refs->lock); | |
767 | ||
56bec294 | 768 | /* |
5d4f98a2 YZ |
769 | * insert both the head node and the new ref without dropping |
770 | * the spin lock | |
56bec294 | 771 | */ |
143bede5 | 772 | add_delayed_ref_head(fs_info, trans, &head_ref->node, bytenr, |
66d7e7f0 | 773 | num_bytes, action, 0); |
5d4f98a2 | 774 | |
143bede5 | 775 | add_delayed_tree_ref(fs_info, trans, &ref->node, bytenr, |
66d7e7f0 AJ |
776 | num_bytes, parent, ref_root, level, action, |
777 | for_cow); | |
5d4f98a2 | 778 | spin_unlock(&delayed_refs->lock); |
546adb0d JS |
779 | if (need_ref_seq(for_cow, ref_root)) |
780 | btrfs_qgroup_record_ref(trans, &ref->node, extent_op); | |
95a06077 | 781 | |
5d4f98a2 YZ |
782 | return 0; |
783 | } | |
784 | ||
785 | /* | |
786 | * add a delayed data ref. it's similar to btrfs_add_delayed_tree_ref. | |
787 | */ | |
66d7e7f0 AJ |
788 | int btrfs_add_delayed_data_ref(struct btrfs_fs_info *fs_info, |
789 | struct btrfs_trans_handle *trans, | |
5d4f98a2 YZ |
790 | u64 bytenr, u64 num_bytes, |
791 | u64 parent, u64 ref_root, | |
792 | u64 owner, u64 offset, int action, | |
66d7e7f0 AJ |
793 | struct btrfs_delayed_extent_op *extent_op, |
794 | int for_cow) | |
5d4f98a2 YZ |
795 | { |
796 | struct btrfs_delayed_data_ref *ref; | |
797 | struct btrfs_delayed_ref_head *head_ref; | |
798 | struct btrfs_delayed_ref_root *delayed_refs; | |
5d4f98a2 YZ |
799 | |
800 | BUG_ON(extent_op && !extent_op->is_data); | |
78a6184a | 801 | ref = kmem_cache_alloc(btrfs_delayed_data_ref_cachep, GFP_NOFS); |
5d4f98a2 YZ |
802 | if (!ref) |
803 | return -ENOMEM; | |
56bec294 | 804 | |
78a6184a | 805 | head_ref = kmem_cache_alloc(btrfs_delayed_ref_head_cachep, GFP_NOFS); |
56bec294 | 806 | if (!head_ref) { |
78a6184a | 807 | kmem_cache_free(btrfs_delayed_data_ref_cachep, ref); |
56bec294 CM |
808 | return -ENOMEM; |
809 | } | |
5d4f98a2 YZ |
810 | |
811 | head_ref->extent_op = extent_op; | |
812 | ||
56bec294 CM |
813 | delayed_refs = &trans->transaction->delayed_refs; |
814 | spin_lock(&delayed_refs->lock); | |
815 | ||
816 | /* | |
817 | * insert both the head node and the new ref without dropping | |
818 | * the spin lock | |
819 | */ | |
143bede5 | 820 | add_delayed_ref_head(fs_info, trans, &head_ref->node, bytenr, |
66d7e7f0 | 821 | num_bytes, action, 1); |
56bec294 | 822 | |
143bede5 | 823 | add_delayed_data_ref(fs_info, trans, &ref->node, bytenr, |
66d7e7f0 AJ |
824 | num_bytes, parent, ref_root, owner, offset, |
825 | action, for_cow); | |
5d4f98a2 | 826 | spin_unlock(&delayed_refs->lock); |
546adb0d JS |
827 | if (need_ref_seq(for_cow, ref_root)) |
828 | btrfs_qgroup_record_ref(trans, &ref->node, extent_op); | |
95a06077 | 829 | |
5d4f98a2 YZ |
830 | return 0; |
831 | } | |
832 | ||
66d7e7f0 AJ |
833 | int btrfs_add_delayed_extent_op(struct btrfs_fs_info *fs_info, |
834 | struct btrfs_trans_handle *trans, | |
5d4f98a2 YZ |
835 | u64 bytenr, u64 num_bytes, |
836 | struct btrfs_delayed_extent_op *extent_op) | |
837 | { | |
838 | struct btrfs_delayed_ref_head *head_ref; | |
839 | struct btrfs_delayed_ref_root *delayed_refs; | |
5d4f98a2 | 840 | |
78a6184a | 841 | head_ref = kmem_cache_alloc(btrfs_delayed_ref_head_cachep, GFP_NOFS); |
5d4f98a2 YZ |
842 | if (!head_ref) |
843 | return -ENOMEM; | |
844 | ||
845 | head_ref->extent_op = extent_op; | |
846 | ||
847 | delayed_refs = &trans->transaction->delayed_refs; | |
848 | spin_lock(&delayed_refs->lock); | |
849 | ||
143bede5 | 850 | add_delayed_ref_head(fs_info, trans, &head_ref->node, bytenr, |
5d4f98a2 YZ |
851 | num_bytes, BTRFS_UPDATE_DELAYED_HEAD, |
852 | extent_op->is_data); | |
5d4f98a2 | 853 | |
56bec294 CM |
854 | spin_unlock(&delayed_refs->lock); |
855 | return 0; | |
856 | } | |
857 | ||
1887be66 CM |
858 | /* |
859 | * this does a simple search for the head node for a given extent. | |
860 | * It must be called with the delayed ref spinlock held, and it returns | |
861 | * the head node if any where found, or NULL if not. | |
862 | */ | |
863 | struct btrfs_delayed_ref_head * | |
864 | btrfs_find_delayed_ref_head(struct btrfs_trans_handle *trans, u64 bytenr) | |
865 | { | |
866 | struct btrfs_delayed_ref_node *ref; | |
867 | struct btrfs_delayed_ref_root *delayed_refs; | |
868 | ||
869 | delayed_refs = &trans->transaction->delayed_refs; | |
d1270cd9 | 870 | ref = find_ref_head(&delayed_refs->root, bytenr, NULL, 0); |
1887be66 CM |
871 | if (ref) |
872 | return btrfs_delayed_node_to_head(ref); | |
873 | return NULL; | |
874 | } | |
78a6184a MX |
875 | |
876 | void btrfs_delayed_ref_exit(void) | |
877 | { | |
878 | if (btrfs_delayed_ref_head_cachep) | |
879 | kmem_cache_destroy(btrfs_delayed_ref_head_cachep); | |
880 | if (btrfs_delayed_tree_ref_cachep) | |
881 | kmem_cache_destroy(btrfs_delayed_tree_ref_cachep); | |
882 | if (btrfs_delayed_data_ref_cachep) | |
883 | kmem_cache_destroy(btrfs_delayed_data_ref_cachep); | |
884 | if (btrfs_delayed_extent_op_cachep) | |
885 | kmem_cache_destroy(btrfs_delayed_extent_op_cachep); | |
886 | } | |
887 | ||
888 | int btrfs_delayed_ref_init(void) | |
889 | { | |
890 | btrfs_delayed_ref_head_cachep = kmem_cache_create( | |
891 | "btrfs_delayed_ref_head", | |
892 | sizeof(struct btrfs_delayed_ref_head), 0, | |
893 | SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); | |
894 | if (!btrfs_delayed_ref_head_cachep) | |
895 | goto fail; | |
896 | ||
897 | btrfs_delayed_tree_ref_cachep = kmem_cache_create( | |
898 | "btrfs_delayed_tree_ref", | |
899 | sizeof(struct btrfs_delayed_tree_ref), 0, | |
900 | SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); | |
901 | if (!btrfs_delayed_tree_ref_cachep) | |
902 | goto fail; | |
903 | ||
904 | btrfs_delayed_data_ref_cachep = kmem_cache_create( | |
905 | "btrfs_delayed_data_ref", | |
906 | sizeof(struct btrfs_delayed_data_ref), 0, | |
907 | SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); | |
908 | if (!btrfs_delayed_data_ref_cachep) | |
909 | goto fail; | |
910 | ||
911 | btrfs_delayed_extent_op_cachep = kmem_cache_create( | |
912 | "btrfs_delayed_extent_op", | |
913 | sizeof(struct btrfs_delayed_extent_op), 0, | |
914 | SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); | |
915 | if (!btrfs_delayed_extent_op_cachep) | |
916 | goto fail; | |
917 | ||
918 | return 0; | |
919 | fail: | |
920 | btrfs_delayed_ref_exit(); | |
921 | return -ENOMEM; | |
922 | } |