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>
20 #include <linux/slab.h>
21 #include <linux/sort.h>
22 #include "ctree.h"
23 #include "delayed-ref.h"
24 #include "transaction.h"
25 #include "qgroup.h"
26
27 struct kmem_cache *btrfs_delayed_ref_head_cachep;
28 struct kmem_cache *btrfs_delayed_tree_ref_cachep;
29 struct kmem_cache *btrfs_delayed_data_ref_cachep;
30 struct kmem_cache *btrfs_delayed_extent_op_cachep;
31 /*
32 * delayed back reference update tracking. For subvolume trees
33 * we queue up extent allocations and backref maintenance for
34 * delayed processing. This avoids deep call chains where we
35 * add extents in the middle of btrfs_search_slot, and it allows
36 * us to buffer up frequently modified backrefs in an rb tree instead
37 * of hammering updates on the extent allocation tree.
38 */
39
40 /*
41 * compare two delayed tree backrefs with same bytenr and type
42 */
comp_tree_refs(struct btrfs_delayed_tree_ref * ref2,struct btrfs_delayed_tree_ref * ref1,int type)43 static int comp_tree_refs(struct btrfs_delayed_tree_ref *ref2,
44 struct btrfs_delayed_tree_ref *ref1, int type)
45 {
46 if (type == BTRFS_TREE_BLOCK_REF_KEY) {
47 if (ref1->root < ref2->root)
48 return -1;
49 if (ref1->root > ref2->root)
50 return 1;
51 } else {
52 if (ref1->parent < ref2->parent)
53 return -1;
54 if (ref1->parent > ref2->parent)
55 return 1;
56 }
57 return 0;
58 }
59
60 /*
61 * compare two delayed data backrefs with same bytenr and type
62 */
comp_data_refs(struct btrfs_delayed_data_ref * ref2,struct btrfs_delayed_data_ref * ref1)63 static int comp_data_refs(struct btrfs_delayed_data_ref *ref2,
64 struct btrfs_delayed_data_ref *ref1)
65 {
66 if (ref1->node.type == BTRFS_EXTENT_DATA_REF_KEY) {
67 if (ref1->root < ref2->root)
68 return -1;
69 if (ref1->root > ref2->root)
70 return 1;
71 if (ref1->objectid < ref2->objectid)
72 return -1;
73 if (ref1->objectid > ref2->objectid)
74 return 1;
75 if (ref1->offset < ref2->offset)
76 return -1;
77 if (ref1->offset > ref2->offset)
78 return 1;
79 } else {
80 if (ref1->parent < ref2->parent)
81 return -1;
82 if (ref1->parent > ref2->parent)
83 return 1;
84 }
85 return 0;
86 }
87
88 /* insert a new ref to head ref rbtree */
htree_insert(struct rb_root * root,struct rb_node * node)89 static struct btrfs_delayed_ref_head *htree_insert(struct rb_root *root,
90 struct rb_node *node)
91 {
92 struct rb_node **p = &root->rb_node;
93 struct rb_node *parent_node = NULL;
94 struct btrfs_delayed_ref_head *entry;
95 struct btrfs_delayed_ref_head *ins;
96 u64 bytenr;
97
98 ins = rb_entry(node, struct btrfs_delayed_ref_head, href_node);
99 bytenr = ins->node.bytenr;
100 while (*p) {
101 parent_node = *p;
102 entry = rb_entry(parent_node, struct btrfs_delayed_ref_head,
103 href_node);
104
105 if (bytenr < entry->node.bytenr)
106 p = &(*p)->rb_left;
107 else if (bytenr > entry->node.bytenr)
108 p = &(*p)->rb_right;
109 else
110 return entry;
111 }
112
113 rb_link_node(node, parent_node, p);
114 rb_insert_color(node, root);
115 return NULL;
116 }
117
118 /*
119 * find an head entry based on bytenr. This returns the delayed ref
120 * head if it was able to find one, or NULL if nothing was in that spot.
121 * If return_bigger is given, the next bigger entry is returned if no exact
122 * match is found.
123 */
124 static struct btrfs_delayed_ref_head *
find_ref_head(struct rb_root * root,u64 bytenr,int return_bigger)125 find_ref_head(struct rb_root *root, u64 bytenr,
126 int return_bigger)
127 {
128 struct rb_node *n;
129 struct btrfs_delayed_ref_head *entry;
130
131 n = root->rb_node;
132 entry = NULL;
133 while (n) {
134 entry = rb_entry(n, struct btrfs_delayed_ref_head, href_node);
135
136 if (bytenr < entry->node.bytenr)
137 n = n->rb_left;
138 else if (bytenr > entry->node.bytenr)
139 n = n->rb_right;
140 else
141 return entry;
142 }
143 if (entry && return_bigger) {
144 if (bytenr > entry->node.bytenr) {
145 n = rb_next(&entry->href_node);
146 if (!n)
147 n = rb_first(root);
148 entry = rb_entry(n, struct btrfs_delayed_ref_head,
149 href_node);
150 return entry;
151 }
152 return entry;
153 }
154 return NULL;
155 }
156
btrfs_delayed_ref_lock(struct btrfs_trans_handle * trans,struct btrfs_delayed_ref_head * head)157 int btrfs_delayed_ref_lock(struct btrfs_trans_handle *trans,
158 struct btrfs_delayed_ref_head *head)
159 {
160 struct btrfs_delayed_ref_root *delayed_refs;
161
162 delayed_refs = &trans->transaction->delayed_refs;
163 assert_spin_locked(&delayed_refs->lock);
164 if (mutex_trylock(&head->mutex))
165 return 0;
166
167 atomic_inc(&head->node.refs);
168 spin_unlock(&delayed_refs->lock);
169
170 mutex_lock(&head->mutex);
171 spin_lock(&delayed_refs->lock);
172 if (!head->node.in_tree) {
173 mutex_unlock(&head->mutex);
174 btrfs_put_delayed_ref(&head->node);
175 return -EAGAIN;
176 }
177 btrfs_put_delayed_ref(&head->node);
178 return 0;
179 }
180
drop_delayed_ref(struct btrfs_trans_handle * trans,struct btrfs_delayed_ref_root * delayed_refs,struct btrfs_delayed_ref_head * head,struct btrfs_delayed_ref_node * ref)181 static inline void drop_delayed_ref(struct btrfs_trans_handle *trans,
182 struct btrfs_delayed_ref_root *delayed_refs,
183 struct btrfs_delayed_ref_head *head,
184 struct btrfs_delayed_ref_node *ref)
185 {
186 if (btrfs_delayed_ref_is_head(ref)) {
187 head = btrfs_delayed_node_to_head(ref);
188 rb_erase(&head->href_node, &delayed_refs->href_root);
189 } else {
190 assert_spin_locked(&head->lock);
191 list_del(&ref->list);
192 }
193 ref->in_tree = 0;
194 btrfs_put_delayed_ref(ref);
195 atomic_dec(&delayed_refs->num_entries);
196 if (trans->delayed_ref_updates)
197 trans->delayed_ref_updates--;
198 }
199
merge_ref(struct btrfs_trans_handle * trans,struct btrfs_delayed_ref_root * delayed_refs,struct btrfs_delayed_ref_head * head,struct btrfs_delayed_ref_node * ref,u64 seq)200 static bool merge_ref(struct btrfs_trans_handle *trans,
201 struct btrfs_delayed_ref_root *delayed_refs,
202 struct btrfs_delayed_ref_head *head,
203 struct btrfs_delayed_ref_node *ref,
204 u64 seq)
205 {
206 struct btrfs_delayed_ref_node *next;
207 bool done = false;
208
209 next = list_first_entry(&head->ref_list, struct btrfs_delayed_ref_node,
210 list);
211 while (!done && &next->list != &head->ref_list) {
212 int mod;
213 struct btrfs_delayed_ref_node *next2;
214
215 next2 = list_next_entry(next, list);
216
217 if (next == ref)
218 goto next;
219
220 if (seq && next->seq >= seq)
221 goto next;
222
223 if (next->type != ref->type)
224 goto next;
225
226 if ((ref->type == BTRFS_TREE_BLOCK_REF_KEY ||
227 ref->type == BTRFS_SHARED_BLOCK_REF_KEY) &&
228 comp_tree_refs(btrfs_delayed_node_to_tree_ref(ref),
229 btrfs_delayed_node_to_tree_ref(next),
230 ref->type))
231 goto next;
232 if ((ref->type == BTRFS_EXTENT_DATA_REF_KEY ||
233 ref->type == BTRFS_SHARED_DATA_REF_KEY) &&
234 comp_data_refs(btrfs_delayed_node_to_data_ref(ref),
235 btrfs_delayed_node_to_data_ref(next)))
236 goto next;
237
238 if (ref->action == next->action) {
239 mod = next->ref_mod;
240 } else {
241 if (ref->ref_mod < next->ref_mod) {
242 swap(ref, next);
243 done = true;
244 }
245 mod = -next->ref_mod;
246 }
247
248 drop_delayed_ref(trans, delayed_refs, head, next);
249 ref->ref_mod += mod;
250 if (ref->ref_mod == 0) {
251 drop_delayed_ref(trans, delayed_refs, head, ref);
252 done = true;
253 } else {
254 /*
255 * Can't have multiples of the same ref on a tree block.
256 */
257 WARN_ON(ref->type == BTRFS_TREE_BLOCK_REF_KEY ||
258 ref->type == BTRFS_SHARED_BLOCK_REF_KEY);
259 }
260 next:
261 next = next2;
262 }
263
264 return done;
265 }
266
btrfs_merge_delayed_refs(struct btrfs_trans_handle * trans,struct btrfs_fs_info * fs_info,struct btrfs_delayed_ref_root * delayed_refs,struct btrfs_delayed_ref_head * head)267 void btrfs_merge_delayed_refs(struct btrfs_trans_handle *trans,
268 struct btrfs_fs_info *fs_info,
269 struct btrfs_delayed_ref_root *delayed_refs,
270 struct btrfs_delayed_ref_head *head)
271 {
272 struct btrfs_delayed_ref_node *ref;
273 u64 seq = 0;
274
275 assert_spin_locked(&head->lock);
276
277 if (list_empty(&head->ref_list))
278 return;
279
280 /* We don't have too many refs to merge for data. */
281 if (head->is_data)
282 return;
283
284 spin_lock(&fs_info->tree_mod_seq_lock);
285 if (!list_empty(&fs_info->tree_mod_seq_list)) {
286 struct seq_list *elem;
287
288 elem = list_first_entry(&fs_info->tree_mod_seq_list,
289 struct seq_list, list);
290 seq = elem->seq;
291 }
292 spin_unlock(&fs_info->tree_mod_seq_lock);
293
294 ref = list_first_entry(&head->ref_list, struct btrfs_delayed_ref_node,
295 list);
296 while (&ref->list != &head->ref_list) {
297 if (seq && ref->seq >= seq)
298 goto next;
299
300 if (merge_ref(trans, delayed_refs, head, ref, seq)) {
301 if (list_empty(&head->ref_list))
302 break;
303 ref = list_first_entry(&head->ref_list,
304 struct btrfs_delayed_ref_node,
305 list);
306 continue;
307 }
308 next:
309 ref = list_next_entry(ref, list);
310 }
311 }
312
btrfs_check_delayed_seq(struct btrfs_fs_info * fs_info,struct btrfs_delayed_ref_root * delayed_refs,u64 seq)313 int btrfs_check_delayed_seq(struct btrfs_fs_info *fs_info,
314 struct btrfs_delayed_ref_root *delayed_refs,
315 u64 seq)
316 {
317 struct seq_list *elem;
318 int ret = 0;
319
320 spin_lock(&fs_info->tree_mod_seq_lock);
321 if (!list_empty(&fs_info->tree_mod_seq_list)) {
322 elem = list_first_entry(&fs_info->tree_mod_seq_list,
323 struct seq_list, list);
324 if (seq >= elem->seq) {
325 btrfs_debug(fs_info,
326 "holding back delayed_ref %#x.%x, lowest is %#x.%x (%p)",
327 (u32)(seq >> 32), (u32)seq,
328 (u32)(elem->seq >> 32), (u32)elem->seq,
329 delayed_refs);
330 ret = 1;
331 }
332 }
333
334 spin_unlock(&fs_info->tree_mod_seq_lock);
335 return ret;
336 }
337
338 struct btrfs_delayed_ref_head *
btrfs_select_ref_head(struct btrfs_trans_handle * trans)339 btrfs_select_ref_head(struct btrfs_trans_handle *trans)
340 {
341 struct btrfs_delayed_ref_root *delayed_refs;
342 struct btrfs_delayed_ref_head *head;
343 u64 start;
344 bool loop = false;
345
346 delayed_refs = &trans->transaction->delayed_refs;
347
348 again:
349 start = delayed_refs->run_delayed_start;
350 head = find_ref_head(&delayed_refs->href_root, start, 1);
351 if (!head && !loop) {
352 delayed_refs->run_delayed_start = 0;
353 start = 0;
354 loop = true;
355 head = find_ref_head(&delayed_refs->href_root, start, 1);
356 if (!head)
357 return NULL;
358 } else if (!head && loop) {
359 return NULL;
360 }
361
362 while (head->processing) {
363 struct rb_node *node;
364
365 node = rb_next(&head->href_node);
366 if (!node) {
367 if (loop)
368 return NULL;
369 delayed_refs->run_delayed_start = 0;
370 start = 0;
371 loop = true;
372 goto again;
373 }
374 head = rb_entry(node, struct btrfs_delayed_ref_head,
375 href_node);
376 }
377
378 head->processing = 1;
379 WARN_ON(delayed_refs->num_heads_ready == 0);
380 delayed_refs->num_heads_ready--;
381 delayed_refs->run_delayed_start = head->node.bytenr +
382 head->node.num_bytes;
383 return head;
384 }
385
386 /*
387 * Helper to insert the ref_node to the tail or merge with tail.
388 *
389 * Return 0 for insert.
390 * Return >0 for merge.
391 */
392 static int
add_delayed_ref_tail_merge(struct btrfs_trans_handle * trans,struct btrfs_delayed_ref_root * root,struct btrfs_delayed_ref_head * href,struct btrfs_delayed_ref_node * ref)393 add_delayed_ref_tail_merge(struct btrfs_trans_handle *trans,
394 struct btrfs_delayed_ref_root *root,
395 struct btrfs_delayed_ref_head *href,
396 struct btrfs_delayed_ref_node *ref)
397 {
398 struct btrfs_delayed_ref_node *exist;
399 int mod;
400 int ret = 0;
401
402 spin_lock(&href->lock);
403 /* Check whether we can merge the tail node with ref */
404 if (list_empty(&href->ref_list))
405 goto add_tail;
406 exist = list_entry(href->ref_list.prev, struct btrfs_delayed_ref_node,
407 list);
408 /* No need to compare bytenr nor is_head */
409 if (exist->type != ref->type || exist->seq != ref->seq)
410 goto add_tail;
411
412 if ((exist->type == BTRFS_TREE_BLOCK_REF_KEY ||
413 exist->type == BTRFS_SHARED_BLOCK_REF_KEY) &&
414 comp_tree_refs(btrfs_delayed_node_to_tree_ref(exist),
415 btrfs_delayed_node_to_tree_ref(ref),
416 ref->type))
417 goto add_tail;
418 if ((exist->type == BTRFS_EXTENT_DATA_REF_KEY ||
419 exist->type == BTRFS_SHARED_DATA_REF_KEY) &&
420 comp_data_refs(btrfs_delayed_node_to_data_ref(exist),
421 btrfs_delayed_node_to_data_ref(ref)))
422 goto add_tail;
423
424 /* Now we are sure we can merge */
425 ret = 1;
426 if (exist->action == ref->action) {
427 mod = ref->ref_mod;
428 } else {
429 /* Need to change action */
430 if (exist->ref_mod < ref->ref_mod) {
431 exist->action = ref->action;
432 mod = -exist->ref_mod;
433 exist->ref_mod = ref->ref_mod;
434 } else
435 mod = -ref->ref_mod;
436 }
437 exist->ref_mod += mod;
438
439 /* remove existing tail if its ref_mod is zero */
440 if (exist->ref_mod == 0)
441 drop_delayed_ref(trans, root, href, exist);
442 spin_unlock(&href->lock);
443 return ret;
444
445 add_tail:
446 list_add_tail(&ref->list, &href->ref_list);
447 atomic_inc(&root->num_entries);
448 trans->delayed_ref_updates++;
449 spin_unlock(&href->lock);
450 return ret;
451 }
452
453 /*
454 * helper function to update the accounting in the head ref
455 * existing and update must have the same bytenr
456 */
457 static noinline void
update_existing_head_ref(struct btrfs_delayed_ref_root * delayed_refs,struct btrfs_delayed_ref_node * existing,struct btrfs_delayed_ref_node * update)458 update_existing_head_ref(struct btrfs_delayed_ref_root *delayed_refs,
459 struct btrfs_delayed_ref_node *existing,
460 struct btrfs_delayed_ref_node *update)
461 {
462 struct btrfs_delayed_ref_head *existing_ref;
463 struct btrfs_delayed_ref_head *ref;
464 int old_ref_mod;
465
466 existing_ref = btrfs_delayed_node_to_head(existing);
467 ref = btrfs_delayed_node_to_head(update);
468 BUG_ON(existing_ref->is_data != ref->is_data);
469
470 spin_lock(&existing_ref->lock);
471 if (ref->must_insert_reserved) {
472 /* if the extent was freed and then
473 * reallocated before the delayed ref
474 * entries were processed, we can end up
475 * with an existing head ref without
476 * the must_insert_reserved flag set.
477 * Set it again here
478 */
479 existing_ref->must_insert_reserved = ref->must_insert_reserved;
480
481 /*
482 * update the num_bytes so we make sure the accounting
483 * is done correctly
484 */
485 existing->num_bytes = update->num_bytes;
486
487 }
488
489 if (ref->extent_op) {
490 if (!existing_ref->extent_op) {
491 existing_ref->extent_op = ref->extent_op;
492 } else {
493 if (ref->extent_op->update_key) {
494 memcpy(&existing_ref->extent_op->key,
495 &ref->extent_op->key,
496 sizeof(ref->extent_op->key));
497 existing_ref->extent_op->update_key = true;
498 }
499 if (ref->extent_op->update_flags) {
500 existing_ref->extent_op->flags_to_set |=
501 ref->extent_op->flags_to_set;
502 existing_ref->extent_op->update_flags = true;
503 }
504 btrfs_free_delayed_extent_op(ref->extent_op);
505 }
506 }
507 /*
508 * update the reference mod on the head to reflect this new operation,
509 * only need the lock for this case cause we could be processing it
510 * currently, for refs we just added we know we're a-ok.
511 */
512 old_ref_mod = existing_ref->total_ref_mod;
513 existing->ref_mod += update->ref_mod;
514 existing_ref->total_ref_mod += update->ref_mod;
515
516 /*
517 * If we are going to from a positive ref mod to a negative or vice
518 * versa we need to make sure to adjust pending_csums accordingly.
519 */
520 if (existing_ref->is_data) {
521 if (existing_ref->total_ref_mod >= 0 && old_ref_mod < 0)
522 delayed_refs->pending_csums -= existing->num_bytes;
523 if (existing_ref->total_ref_mod < 0 && old_ref_mod >= 0)
524 delayed_refs->pending_csums += existing->num_bytes;
525 }
526 spin_unlock(&existing_ref->lock);
527 }
528
529 /*
530 * helper function to actually insert a head node into the rbtree.
531 * this does all the dirty work in terms of maintaining the correct
532 * overall modification count.
533 */
534 static noinline struct btrfs_delayed_ref_head *
add_delayed_ref_head(struct btrfs_fs_info * fs_info,struct btrfs_trans_handle * trans,struct btrfs_delayed_ref_node * ref,struct btrfs_qgroup_extent_record * qrecord,u64 bytenr,u64 num_bytes,u64 ref_root,u64 reserved,int action,int is_data)535 add_delayed_ref_head(struct btrfs_fs_info *fs_info,
536 struct btrfs_trans_handle *trans,
537 struct btrfs_delayed_ref_node *ref,
538 struct btrfs_qgroup_extent_record *qrecord,
539 u64 bytenr, u64 num_bytes, u64 ref_root, u64 reserved,
540 int action, int is_data)
541 {
542 struct btrfs_delayed_ref_head *existing;
543 struct btrfs_delayed_ref_head *head_ref = NULL;
544 struct btrfs_delayed_ref_root *delayed_refs;
545 int count_mod = 1;
546 int must_insert_reserved = 0;
547
548 /* If reserved is provided, it must be a data extent. */
549 BUG_ON(!is_data && reserved);
550
551 /*
552 * the head node stores the sum of all the mods, so dropping a ref
553 * should drop the sum in the head node by one.
554 */
555 if (action == BTRFS_UPDATE_DELAYED_HEAD)
556 count_mod = 0;
557 else if (action == BTRFS_DROP_DELAYED_REF)
558 count_mod = -1;
559
560 /*
561 * BTRFS_ADD_DELAYED_EXTENT means that we need to update
562 * the reserved accounting when the extent is finally added, or
563 * if a later modification deletes the delayed ref without ever
564 * inserting the extent into the extent allocation tree.
565 * ref->must_insert_reserved is the flag used to record
566 * that accounting mods are required.
567 *
568 * Once we record must_insert_reserved, switch the action to
569 * BTRFS_ADD_DELAYED_REF because other special casing is not required.
570 */
571 if (action == BTRFS_ADD_DELAYED_EXTENT)
572 must_insert_reserved = 1;
573 else
574 must_insert_reserved = 0;
575
576 delayed_refs = &trans->transaction->delayed_refs;
577
578 /* first set the basic ref node struct up */
579 atomic_set(&ref->refs, 1);
580 ref->bytenr = bytenr;
581 ref->num_bytes = num_bytes;
582 ref->ref_mod = count_mod;
583 ref->type = 0;
584 ref->action = 0;
585 ref->is_head = 1;
586 ref->in_tree = 1;
587 ref->seq = 0;
588
589 head_ref = btrfs_delayed_node_to_head(ref);
590 head_ref->must_insert_reserved = must_insert_reserved;
591 head_ref->is_data = is_data;
592 INIT_LIST_HEAD(&head_ref->ref_list);
593 head_ref->processing = 0;
594 head_ref->total_ref_mod = count_mod;
595 head_ref->qgroup_reserved = 0;
596 head_ref->qgroup_ref_root = 0;
597
598 /* Record qgroup extent info if provided */
599 if (qrecord) {
600 if (ref_root && reserved) {
601 head_ref->qgroup_ref_root = ref_root;
602 head_ref->qgroup_reserved = reserved;
603 }
604
605 qrecord->bytenr = bytenr;
606 qrecord->num_bytes = num_bytes;
607 qrecord->old_roots = NULL;
608
609 if(btrfs_qgroup_insert_dirty_extent_nolock(fs_info,
610 delayed_refs, qrecord))
611 kfree(qrecord);
612 }
613
614 spin_lock_init(&head_ref->lock);
615 mutex_init(&head_ref->mutex);
616
617 trace_add_delayed_ref_head(fs_info, ref, head_ref, action);
618
619 existing = htree_insert(&delayed_refs->href_root,
620 &head_ref->href_node);
621 if (existing) {
622 WARN_ON(ref_root && reserved && existing->qgroup_ref_root
623 && existing->qgroup_reserved);
624 update_existing_head_ref(delayed_refs, &existing->node, ref);
625 /*
626 * we've updated the existing ref, free the newly
627 * allocated ref
628 */
629 kmem_cache_free(btrfs_delayed_ref_head_cachep, head_ref);
630 head_ref = existing;
631 } else {
632 if (is_data && count_mod < 0)
633 delayed_refs->pending_csums += num_bytes;
634 delayed_refs->num_heads++;
635 delayed_refs->num_heads_ready++;
636 atomic_inc(&delayed_refs->num_entries);
637 trans->delayed_ref_updates++;
638 }
639 return head_ref;
640 }
641
642 /*
643 * helper to insert a delayed tree ref into the rbtree.
644 */
645 static noinline void
add_delayed_tree_ref(struct btrfs_fs_info * fs_info,struct btrfs_trans_handle * trans,struct btrfs_delayed_ref_head * head_ref,struct btrfs_delayed_ref_node * ref,u64 bytenr,u64 num_bytes,u64 parent,u64 ref_root,int level,int action)646 add_delayed_tree_ref(struct btrfs_fs_info *fs_info,
647 struct btrfs_trans_handle *trans,
648 struct btrfs_delayed_ref_head *head_ref,
649 struct btrfs_delayed_ref_node *ref, u64 bytenr,
650 u64 num_bytes, u64 parent, u64 ref_root, int level,
651 int action)
652 {
653 struct btrfs_delayed_tree_ref *full_ref;
654 struct btrfs_delayed_ref_root *delayed_refs;
655 u64 seq = 0;
656 int ret;
657
658 if (action == BTRFS_ADD_DELAYED_EXTENT)
659 action = BTRFS_ADD_DELAYED_REF;
660
661 if (is_fstree(ref_root))
662 seq = atomic64_read(&fs_info->tree_mod_seq);
663 delayed_refs = &trans->transaction->delayed_refs;
664
665 /* first set the basic ref node struct up */
666 atomic_set(&ref->refs, 1);
667 ref->bytenr = bytenr;
668 ref->num_bytes = num_bytes;
669 ref->ref_mod = 1;
670 ref->action = action;
671 ref->is_head = 0;
672 ref->in_tree = 1;
673 ref->seq = seq;
674
675 full_ref = btrfs_delayed_node_to_tree_ref(ref);
676 full_ref->parent = parent;
677 full_ref->root = ref_root;
678 if (parent)
679 ref->type = BTRFS_SHARED_BLOCK_REF_KEY;
680 else
681 ref->type = BTRFS_TREE_BLOCK_REF_KEY;
682 full_ref->level = level;
683
684 trace_add_delayed_tree_ref(fs_info, ref, full_ref, action);
685
686 ret = add_delayed_ref_tail_merge(trans, delayed_refs, head_ref, ref);
687
688 /*
689 * XXX: memory should be freed at the same level allocated.
690 * But bad practice is anywhere... Follow it now. Need cleanup.
691 */
692 if (ret > 0)
693 kmem_cache_free(btrfs_delayed_tree_ref_cachep, full_ref);
694 }
695
696 /*
697 * helper to insert a delayed data ref into the rbtree.
698 */
699 static noinline void
add_delayed_data_ref(struct btrfs_fs_info * fs_info,struct btrfs_trans_handle * trans,struct btrfs_delayed_ref_head * head_ref,struct btrfs_delayed_ref_node * ref,u64 bytenr,u64 num_bytes,u64 parent,u64 ref_root,u64 owner,u64 offset,int action)700 add_delayed_data_ref(struct btrfs_fs_info *fs_info,
701 struct btrfs_trans_handle *trans,
702 struct btrfs_delayed_ref_head *head_ref,
703 struct btrfs_delayed_ref_node *ref, u64 bytenr,
704 u64 num_bytes, u64 parent, u64 ref_root, u64 owner,
705 u64 offset, int action)
706 {
707 struct btrfs_delayed_data_ref *full_ref;
708 struct btrfs_delayed_ref_root *delayed_refs;
709 u64 seq = 0;
710 int ret;
711
712 if (action == BTRFS_ADD_DELAYED_EXTENT)
713 action = BTRFS_ADD_DELAYED_REF;
714
715 delayed_refs = &trans->transaction->delayed_refs;
716
717 if (is_fstree(ref_root))
718 seq = atomic64_read(&fs_info->tree_mod_seq);
719
720 /* first set the basic ref node struct up */
721 atomic_set(&ref->refs, 1);
722 ref->bytenr = bytenr;
723 ref->num_bytes = num_bytes;
724 ref->ref_mod = 1;
725 ref->action = action;
726 ref->is_head = 0;
727 ref->in_tree = 1;
728 ref->seq = seq;
729
730 full_ref = btrfs_delayed_node_to_data_ref(ref);
731 full_ref->parent = parent;
732 full_ref->root = ref_root;
733 if (parent)
734 ref->type = BTRFS_SHARED_DATA_REF_KEY;
735 else
736 ref->type = BTRFS_EXTENT_DATA_REF_KEY;
737
738 full_ref->objectid = owner;
739 full_ref->offset = offset;
740
741 trace_add_delayed_data_ref(fs_info, ref, full_ref, action);
742
743 ret = add_delayed_ref_tail_merge(trans, delayed_refs, head_ref, ref);
744
745 if (ret > 0)
746 kmem_cache_free(btrfs_delayed_data_ref_cachep, full_ref);
747 }
748
749 /*
750 * add a delayed tree ref. This does all of the accounting required
751 * to make sure the delayed ref is eventually processed before this
752 * transaction commits.
753 */
btrfs_add_delayed_tree_ref(struct btrfs_fs_info * fs_info,struct btrfs_trans_handle * trans,u64 bytenr,u64 num_bytes,u64 parent,u64 ref_root,int level,int action,struct btrfs_delayed_extent_op * extent_op)754 int btrfs_add_delayed_tree_ref(struct btrfs_fs_info *fs_info,
755 struct btrfs_trans_handle *trans,
756 u64 bytenr, u64 num_bytes, u64 parent,
757 u64 ref_root, int level, int action,
758 struct btrfs_delayed_extent_op *extent_op)
759 {
760 struct btrfs_delayed_tree_ref *ref;
761 struct btrfs_delayed_ref_head *head_ref;
762 struct btrfs_delayed_ref_root *delayed_refs;
763 struct btrfs_qgroup_extent_record *record = NULL;
764
765 BUG_ON(extent_op && extent_op->is_data);
766 ref = kmem_cache_alloc(btrfs_delayed_tree_ref_cachep, GFP_NOFS);
767 if (!ref)
768 return -ENOMEM;
769
770 head_ref = kmem_cache_alloc(btrfs_delayed_ref_head_cachep, GFP_NOFS);
771 if (!head_ref)
772 goto free_ref;
773
774 if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) &&
775 is_fstree(ref_root)) {
776 record = kmalloc(sizeof(*record), GFP_NOFS);
777 if (!record)
778 goto free_head_ref;
779 }
780
781 head_ref->extent_op = extent_op;
782
783 delayed_refs = &trans->transaction->delayed_refs;
784 spin_lock(&delayed_refs->lock);
785
786 /*
787 * insert both the head node and the new ref without dropping
788 * the spin lock
789 */
790 head_ref = add_delayed_ref_head(fs_info, trans, &head_ref->node, record,
791 bytenr, num_bytes, 0, 0, action, 0);
792
793 add_delayed_tree_ref(fs_info, trans, head_ref, &ref->node, bytenr,
794 num_bytes, parent, ref_root, level, action);
795 spin_unlock(&delayed_refs->lock);
796
797 return 0;
798
799 free_head_ref:
800 kmem_cache_free(btrfs_delayed_ref_head_cachep, head_ref);
801 free_ref:
802 kmem_cache_free(btrfs_delayed_tree_ref_cachep, ref);
803
804 return -ENOMEM;
805 }
806
807 /*
808 * add a delayed data ref. it's similar to btrfs_add_delayed_tree_ref.
809 */
btrfs_add_delayed_data_ref(struct btrfs_fs_info * fs_info,struct btrfs_trans_handle * trans,u64 bytenr,u64 num_bytes,u64 parent,u64 ref_root,u64 owner,u64 offset,u64 reserved,int action,struct btrfs_delayed_extent_op * extent_op)810 int btrfs_add_delayed_data_ref(struct btrfs_fs_info *fs_info,
811 struct btrfs_trans_handle *trans,
812 u64 bytenr, u64 num_bytes,
813 u64 parent, u64 ref_root,
814 u64 owner, u64 offset, u64 reserved, int action,
815 struct btrfs_delayed_extent_op *extent_op)
816 {
817 struct btrfs_delayed_data_ref *ref;
818 struct btrfs_delayed_ref_head *head_ref;
819 struct btrfs_delayed_ref_root *delayed_refs;
820 struct btrfs_qgroup_extent_record *record = NULL;
821
822 BUG_ON(extent_op && !extent_op->is_data);
823 ref = kmem_cache_alloc(btrfs_delayed_data_ref_cachep, GFP_NOFS);
824 if (!ref)
825 return -ENOMEM;
826
827 head_ref = kmem_cache_alloc(btrfs_delayed_ref_head_cachep, GFP_NOFS);
828 if (!head_ref) {
829 kmem_cache_free(btrfs_delayed_data_ref_cachep, ref);
830 return -ENOMEM;
831 }
832
833 if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) &&
834 is_fstree(ref_root)) {
835 record = kmalloc(sizeof(*record), GFP_NOFS);
836 if (!record) {
837 kmem_cache_free(btrfs_delayed_data_ref_cachep, ref);
838 kmem_cache_free(btrfs_delayed_ref_head_cachep,
839 head_ref);
840 return -ENOMEM;
841 }
842 }
843
844 head_ref->extent_op = extent_op;
845
846 delayed_refs = &trans->transaction->delayed_refs;
847 spin_lock(&delayed_refs->lock);
848
849 /*
850 * insert both the head node and the new ref without dropping
851 * the spin lock
852 */
853 head_ref = add_delayed_ref_head(fs_info, trans, &head_ref->node, record,
854 bytenr, num_bytes, ref_root, reserved,
855 action, 1);
856
857 add_delayed_data_ref(fs_info, trans, head_ref, &ref->node, bytenr,
858 num_bytes, parent, ref_root, owner, offset,
859 action);
860 spin_unlock(&delayed_refs->lock);
861
862 return 0;
863 }
864
btrfs_add_delayed_extent_op(struct btrfs_fs_info * fs_info,struct btrfs_trans_handle * trans,u64 bytenr,u64 num_bytes,struct btrfs_delayed_extent_op * extent_op)865 int btrfs_add_delayed_extent_op(struct btrfs_fs_info *fs_info,
866 struct btrfs_trans_handle *trans,
867 u64 bytenr, u64 num_bytes,
868 struct btrfs_delayed_extent_op *extent_op)
869 {
870 struct btrfs_delayed_ref_head *head_ref;
871 struct btrfs_delayed_ref_root *delayed_refs;
872
873 head_ref = kmem_cache_alloc(btrfs_delayed_ref_head_cachep, GFP_NOFS);
874 if (!head_ref)
875 return -ENOMEM;
876
877 head_ref->extent_op = extent_op;
878
879 delayed_refs = &trans->transaction->delayed_refs;
880 spin_lock(&delayed_refs->lock);
881
882 add_delayed_ref_head(fs_info, trans, &head_ref->node, NULL, bytenr,
883 num_bytes, 0, 0, BTRFS_UPDATE_DELAYED_HEAD,
884 extent_op->is_data);
885
886 spin_unlock(&delayed_refs->lock);
887 return 0;
888 }
889
890 /*
891 * this does a simple search for the head node for a given extent.
892 * It must be called with the delayed ref spinlock held, and it returns
893 * the head node if any where found, or NULL if not.
894 */
895 struct btrfs_delayed_ref_head *
btrfs_find_delayed_ref_head(struct btrfs_trans_handle * trans,u64 bytenr)896 btrfs_find_delayed_ref_head(struct btrfs_trans_handle *trans, u64 bytenr)
897 {
898 struct btrfs_delayed_ref_root *delayed_refs;
899
900 delayed_refs = &trans->transaction->delayed_refs;
901 return find_ref_head(&delayed_refs->href_root, bytenr, 0);
902 }
903
btrfs_delayed_ref_exit(void)904 void btrfs_delayed_ref_exit(void)
905 {
906 kmem_cache_destroy(btrfs_delayed_ref_head_cachep);
907 kmem_cache_destroy(btrfs_delayed_tree_ref_cachep);
908 kmem_cache_destroy(btrfs_delayed_data_ref_cachep);
909 kmem_cache_destroy(btrfs_delayed_extent_op_cachep);
910 }
911
btrfs_delayed_ref_init(void)912 int btrfs_delayed_ref_init(void)
913 {
914 btrfs_delayed_ref_head_cachep = kmem_cache_create(
915 "btrfs_delayed_ref_head",
916 sizeof(struct btrfs_delayed_ref_head), 0,
917 SLAB_MEM_SPREAD, NULL);
918 if (!btrfs_delayed_ref_head_cachep)
919 goto fail;
920
921 btrfs_delayed_tree_ref_cachep = kmem_cache_create(
922 "btrfs_delayed_tree_ref",
923 sizeof(struct btrfs_delayed_tree_ref), 0,
924 SLAB_MEM_SPREAD, NULL);
925 if (!btrfs_delayed_tree_ref_cachep)
926 goto fail;
927
928 btrfs_delayed_data_ref_cachep = kmem_cache_create(
929 "btrfs_delayed_data_ref",
930 sizeof(struct btrfs_delayed_data_ref), 0,
931 SLAB_MEM_SPREAD, NULL);
932 if (!btrfs_delayed_data_ref_cachep)
933 goto fail;
934
935 btrfs_delayed_extent_op_cachep = kmem_cache_create(
936 "btrfs_delayed_extent_op",
937 sizeof(struct btrfs_delayed_extent_op), 0,
938 SLAB_MEM_SPREAD, NULL);
939 if (!btrfs_delayed_extent_op_cachep)
940 goto fail;
941
942 return 0;
943 fail:
944 btrfs_delayed_ref_exit();
945 return -ENOMEM;
946 }
947