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 }
197
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)198 static bool merge_ref(struct btrfs_trans_handle *trans,
199 struct btrfs_delayed_ref_root *delayed_refs,
200 struct btrfs_delayed_ref_head *head,
201 struct btrfs_delayed_ref_node *ref,
202 u64 seq)
203 {
204 struct btrfs_delayed_ref_node *next;
205 bool done = false;
206
207 next = list_first_entry(&head->ref_list, struct btrfs_delayed_ref_node,
208 list);
209 while (!done && &next->list != &head->ref_list) {
210 int mod;
211 struct btrfs_delayed_ref_node *next2;
212
213 next2 = list_next_entry(next, list);
214
215 if (next == ref)
216 goto next;
217
218 if (seq && next->seq >= seq)
219 goto next;
220
221 if (next->type != ref->type)
222 goto next;
223
224 if ((ref->type == BTRFS_TREE_BLOCK_REF_KEY ||
225 ref->type == BTRFS_SHARED_BLOCK_REF_KEY) &&
226 comp_tree_refs(btrfs_delayed_node_to_tree_ref(ref),
227 btrfs_delayed_node_to_tree_ref(next),
228 ref->type))
229 goto next;
230 if ((ref->type == BTRFS_EXTENT_DATA_REF_KEY ||
231 ref->type == BTRFS_SHARED_DATA_REF_KEY) &&
232 comp_data_refs(btrfs_delayed_node_to_data_ref(ref),
233 btrfs_delayed_node_to_data_ref(next)))
234 goto next;
235
236 if (ref->action == next->action) {
237 mod = next->ref_mod;
238 } else {
239 if (ref->ref_mod < next->ref_mod) {
240 swap(ref, next);
241 done = true;
242 }
243 mod = -next->ref_mod;
244 }
245
246 drop_delayed_ref(trans, delayed_refs, head, next);
247 ref->ref_mod += mod;
248 if (ref->ref_mod == 0) {
249 drop_delayed_ref(trans, delayed_refs, head, ref);
250 done = true;
251 } else {
252 /*
253 * Can't have multiples of the same ref on a tree block.
254 */
255 WARN_ON(ref->type == BTRFS_TREE_BLOCK_REF_KEY ||
256 ref->type == BTRFS_SHARED_BLOCK_REF_KEY);
257 }
258 next:
259 next = next2;
260 }
261
262 return done;
263 }
264
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)265 void btrfs_merge_delayed_refs(struct btrfs_trans_handle *trans,
266 struct btrfs_fs_info *fs_info,
267 struct btrfs_delayed_ref_root *delayed_refs,
268 struct btrfs_delayed_ref_head *head)
269 {
270 struct btrfs_delayed_ref_node *ref;
271 u64 seq = 0;
272
273 assert_spin_locked(&head->lock);
274
275 if (list_empty(&head->ref_list))
276 return;
277
278 /* We don't have too many refs to merge for data. */
279 if (head->is_data)
280 return;
281
282 read_lock(&fs_info->tree_mod_log_lock);
283 if (!list_empty(&fs_info->tree_mod_seq_list)) {
284 struct seq_list *elem;
285
286 elem = list_first_entry(&fs_info->tree_mod_seq_list,
287 struct seq_list, list);
288 seq = elem->seq;
289 }
290 read_unlock(&fs_info->tree_mod_log_lock);
291
292 ref = list_first_entry(&head->ref_list, struct btrfs_delayed_ref_node,
293 list);
294 while (&ref->list != &head->ref_list) {
295 if (seq && ref->seq >= seq)
296 goto next;
297
298 if (merge_ref(trans, delayed_refs, head, ref, seq)) {
299 if (list_empty(&head->ref_list))
300 break;
301 ref = list_first_entry(&head->ref_list,
302 struct btrfs_delayed_ref_node,
303 list);
304 continue;
305 }
306 next:
307 ref = list_next_entry(ref, list);
308 }
309 }
310
btrfs_check_delayed_seq(struct btrfs_fs_info * fs_info,struct btrfs_delayed_ref_root * delayed_refs,u64 seq)311 int btrfs_check_delayed_seq(struct btrfs_fs_info *fs_info,
312 struct btrfs_delayed_ref_root *delayed_refs,
313 u64 seq)
314 {
315 struct seq_list *elem;
316 int ret = 0;
317
318 read_lock(&fs_info->tree_mod_log_lock);
319 if (!list_empty(&fs_info->tree_mod_seq_list)) {
320 elem = list_first_entry(&fs_info->tree_mod_seq_list,
321 struct seq_list, list);
322 if (seq >= elem->seq) {
323 pr_debug("holding back delayed_ref %#x.%x, lowest is %#x.%x (%p)\n",
324 (u32)(seq >> 32), (u32)seq,
325 (u32)(elem->seq >> 32), (u32)elem->seq,
326 delayed_refs);
327 ret = 1;
328 }
329 }
330
331 read_unlock(&fs_info->tree_mod_log_lock);
332 return ret;
333 }
334
335 struct btrfs_delayed_ref_head *
btrfs_select_ref_head(struct btrfs_trans_handle * trans)336 btrfs_select_ref_head(struct btrfs_trans_handle *trans)
337 {
338 struct btrfs_delayed_ref_root *delayed_refs;
339 struct btrfs_delayed_ref_head *head;
340 u64 start;
341 bool loop = false;
342
343 delayed_refs = &trans->transaction->delayed_refs;
344
345 again:
346 start = delayed_refs->run_delayed_start;
347 head = find_ref_head(&delayed_refs->href_root, start, 1);
348 if (!head && !loop) {
349 delayed_refs->run_delayed_start = 0;
350 start = 0;
351 loop = true;
352 head = find_ref_head(&delayed_refs->href_root, start, 1);
353 if (!head)
354 return NULL;
355 } else if (!head && loop) {
356 return NULL;
357 }
358
359 while (head->processing) {
360 struct rb_node *node;
361
362 node = rb_next(&head->href_node);
363 if (!node) {
364 if (loop)
365 return NULL;
366 delayed_refs->run_delayed_start = 0;
367 start = 0;
368 loop = true;
369 goto again;
370 }
371 head = rb_entry(node, struct btrfs_delayed_ref_head,
372 href_node);
373 }
374
375 head->processing = 1;
376 WARN_ON(delayed_refs->num_heads_ready == 0);
377 delayed_refs->num_heads_ready--;
378 delayed_refs->run_delayed_start = head->node.bytenr +
379 head->node.num_bytes;
380 return head;
381 }
382
383 /*
384 * Helper to insert the ref_node to the tail or merge with tail.
385 *
386 * Return 0 for insert.
387 * Return >0 for merge.
388 */
389 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)390 add_delayed_ref_tail_merge(struct btrfs_trans_handle *trans,
391 struct btrfs_delayed_ref_root *root,
392 struct btrfs_delayed_ref_head *href,
393 struct btrfs_delayed_ref_node *ref)
394 {
395 struct btrfs_delayed_ref_node *exist;
396 int mod;
397 int ret = 0;
398
399 spin_lock(&href->lock);
400 /* Check whether we can merge the tail node with ref */
401 if (list_empty(&href->ref_list))
402 goto add_tail;
403 exist = list_entry(href->ref_list.prev, struct btrfs_delayed_ref_node,
404 list);
405 /* No need to compare bytenr nor is_head */
406 if (exist->type != ref->type || exist->seq != ref->seq)
407 goto add_tail;
408
409 if ((exist->type == BTRFS_TREE_BLOCK_REF_KEY ||
410 exist->type == BTRFS_SHARED_BLOCK_REF_KEY) &&
411 comp_tree_refs(btrfs_delayed_node_to_tree_ref(exist),
412 btrfs_delayed_node_to_tree_ref(ref),
413 ref->type))
414 goto add_tail;
415 if ((exist->type == BTRFS_EXTENT_DATA_REF_KEY ||
416 exist->type == BTRFS_SHARED_DATA_REF_KEY) &&
417 comp_data_refs(btrfs_delayed_node_to_data_ref(exist),
418 btrfs_delayed_node_to_data_ref(ref)))
419 goto add_tail;
420
421 /* Now we are sure we can merge */
422 ret = 1;
423 if (exist->action == ref->action) {
424 mod = ref->ref_mod;
425 } else {
426 /* Need to change action */
427 if (exist->ref_mod < ref->ref_mod) {
428 exist->action = ref->action;
429 mod = -exist->ref_mod;
430 exist->ref_mod = ref->ref_mod;
431 } else
432 mod = -ref->ref_mod;
433 }
434 exist->ref_mod += mod;
435
436 /* remove existing tail if its ref_mod is zero */
437 if (exist->ref_mod == 0)
438 drop_delayed_ref(trans, root, href, exist);
439 spin_unlock(&href->lock);
440 return ret;
441
442 add_tail:
443 list_add_tail(&ref->list, &href->ref_list);
444 atomic_inc(&root->num_entries);
445 spin_unlock(&href->lock);
446 return ret;
447 }
448
449 /*
450 * helper function to update the accounting in the head ref
451 * existing and update must have the same bytenr
452 */
453 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)454 update_existing_head_ref(struct btrfs_delayed_ref_root *delayed_refs,
455 struct btrfs_delayed_ref_node *existing,
456 struct btrfs_delayed_ref_node *update)
457 {
458 struct btrfs_delayed_ref_head *existing_ref;
459 struct btrfs_delayed_ref_head *ref;
460 int old_ref_mod;
461
462 existing_ref = btrfs_delayed_node_to_head(existing);
463 ref = btrfs_delayed_node_to_head(update);
464 BUG_ON(existing_ref->is_data != ref->is_data);
465
466 spin_lock(&existing_ref->lock);
467 if (ref->must_insert_reserved) {
468 /* if the extent was freed and then
469 * reallocated before the delayed ref
470 * entries were processed, we can end up
471 * with an existing head ref without
472 * the must_insert_reserved flag set.
473 * Set it again here
474 */
475 existing_ref->must_insert_reserved = ref->must_insert_reserved;
476
477 /*
478 * update the num_bytes so we make sure the accounting
479 * is done correctly
480 */
481 existing->num_bytes = update->num_bytes;
482
483 }
484
485 if (ref->extent_op) {
486 if (!existing_ref->extent_op) {
487 existing_ref->extent_op = ref->extent_op;
488 } else {
489 if (ref->extent_op->update_key) {
490 memcpy(&existing_ref->extent_op->key,
491 &ref->extent_op->key,
492 sizeof(ref->extent_op->key));
493 existing_ref->extent_op->update_key = 1;
494 }
495 if (ref->extent_op->update_flags) {
496 existing_ref->extent_op->flags_to_set |=
497 ref->extent_op->flags_to_set;
498 existing_ref->extent_op->update_flags = 1;
499 }
500 btrfs_free_delayed_extent_op(ref->extent_op);
501 }
502 }
503 /*
504 * update the reference mod on the head to reflect this new operation,
505 * only need the lock for this case cause we could be processing it
506 * currently, for refs we just added we know we're a-ok.
507 */
508 old_ref_mod = existing_ref->total_ref_mod;
509 existing->ref_mod += update->ref_mod;
510 existing_ref->total_ref_mod += update->ref_mod;
511
512 /*
513 * If we are going to from a positive ref mod to a negative or vice
514 * versa we need to make sure to adjust pending_csums accordingly.
515 */
516 if (existing_ref->is_data) {
517 if (existing_ref->total_ref_mod >= 0 && old_ref_mod < 0)
518 delayed_refs->pending_csums -= existing->num_bytes;
519 if (existing_ref->total_ref_mod < 0 && old_ref_mod >= 0)
520 delayed_refs->pending_csums += existing->num_bytes;
521 }
522 spin_unlock(&existing_ref->lock);
523 }
524
525 /*
526 * helper function to actually insert a head node into the rbtree.
527 * this does all the dirty work in terms of maintaining the correct
528 * overall modification count.
529 */
530 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)531 add_delayed_ref_head(struct btrfs_fs_info *fs_info,
532 struct btrfs_trans_handle *trans,
533 struct btrfs_delayed_ref_node *ref,
534 struct btrfs_qgroup_extent_record *qrecord,
535 u64 bytenr, u64 num_bytes, u64 ref_root, u64 reserved,
536 int action, int is_data)
537 {
538 struct btrfs_delayed_ref_head *existing;
539 struct btrfs_delayed_ref_head *head_ref = NULL;
540 struct btrfs_delayed_ref_root *delayed_refs;
541 struct btrfs_qgroup_extent_record *qexisting;
542 int count_mod = 1;
543 int must_insert_reserved = 0;
544
545 /* If reserved is provided, it must be a data extent. */
546 BUG_ON(!is_data && reserved);
547
548 /*
549 * the head node stores the sum of all the mods, so dropping a ref
550 * should drop the sum in the head node by one.
551 */
552 if (action == BTRFS_UPDATE_DELAYED_HEAD)
553 count_mod = 0;
554 else if (action == BTRFS_DROP_DELAYED_REF)
555 count_mod = -1;
556
557 /*
558 * BTRFS_ADD_DELAYED_EXTENT means that we need to update
559 * the reserved accounting when the extent is finally added, or
560 * if a later modification deletes the delayed ref without ever
561 * inserting the extent into the extent allocation tree.
562 * ref->must_insert_reserved is the flag used to record
563 * that accounting mods are required.
564 *
565 * Once we record must_insert_reserved, switch the action to
566 * BTRFS_ADD_DELAYED_REF because other special casing is not required.
567 */
568 if (action == BTRFS_ADD_DELAYED_EXTENT)
569 must_insert_reserved = 1;
570 else
571 must_insert_reserved = 0;
572
573 delayed_refs = &trans->transaction->delayed_refs;
574
575 /* first set the basic ref node struct up */
576 atomic_set(&ref->refs, 1);
577 ref->bytenr = bytenr;
578 ref->num_bytes = num_bytes;
579 ref->ref_mod = count_mod;
580 ref->type = 0;
581 ref->action = 0;
582 ref->is_head = 1;
583 ref->in_tree = 1;
584 ref->seq = 0;
585
586 head_ref = btrfs_delayed_node_to_head(ref);
587 head_ref->must_insert_reserved = must_insert_reserved;
588 head_ref->is_data = is_data;
589 INIT_LIST_HEAD(&head_ref->ref_list);
590 head_ref->processing = 0;
591 head_ref->total_ref_mod = count_mod;
592 head_ref->qgroup_reserved = 0;
593 head_ref->qgroup_ref_root = 0;
594
595 /* Record qgroup extent info if provided */
596 if (qrecord) {
597 if (ref_root && reserved) {
598 head_ref->qgroup_ref_root = ref_root;
599 head_ref->qgroup_reserved = reserved;
600 }
601
602 qrecord->bytenr = bytenr;
603 qrecord->num_bytes = num_bytes;
604 qrecord->old_roots = NULL;
605
606 qexisting = btrfs_qgroup_insert_dirty_extent(delayed_refs,
607 qrecord);
608 if (qexisting)
609 kfree(qrecord);
610 }
611
612 spin_lock_init(&head_ref->lock);
613 mutex_init(&head_ref->mutex);
614
615 trace_add_delayed_ref_head(ref, head_ref, action);
616
617 existing = htree_insert(&delayed_refs->href_root,
618 &head_ref->href_node);
619 if (existing) {
620 WARN_ON(ref_root && reserved && existing->qgroup_ref_root
621 && existing->qgroup_reserved);
622 update_existing_head_ref(delayed_refs, &existing->node, ref);
623 /*
624 * we've updated the existing ref, free the newly
625 * allocated ref
626 */
627 kmem_cache_free(btrfs_delayed_ref_head_cachep, head_ref);
628 head_ref = existing;
629 } else {
630 if (is_data && count_mod < 0)
631 delayed_refs->pending_csums += num_bytes;
632 delayed_refs->num_heads++;
633 delayed_refs->num_heads_ready++;
634 atomic_inc(&delayed_refs->num_entries);
635 trans->delayed_ref_updates++;
636 }
637 return head_ref;
638 }
639
640 /*
641 * helper to insert a delayed tree ref into the rbtree.
642 */
643 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)644 add_delayed_tree_ref(struct btrfs_fs_info *fs_info,
645 struct btrfs_trans_handle *trans,
646 struct btrfs_delayed_ref_head *head_ref,
647 struct btrfs_delayed_ref_node *ref, u64 bytenr,
648 u64 num_bytes, u64 parent, u64 ref_root, int level,
649 int action)
650 {
651 struct btrfs_delayed_tree_ref *full_ref;
652 struct btrfs_delayed_ref_root *delayed_refs;
653 u64 seq = 0;
654 int ret;
655
656 if (action == BTRFS_ADD_DELAYED_EXTENT)
657 action = BTRFS_ADD_DELAYED_REF;
658
659 if (is_fstree(ref_root))
660 seq = atomic64_read(&fs_info->tree_mod_seq);
661 delayed_refs = &trans->transaction->delayed_refs;
662
663 /* first set the basic ref node struct up */
664 atomic_set(&ref->refs, 1);
665 ref->bytenr = bytenr;
666 ref->num_bytes = num_bytes;
667 ref->ref_mod = 1;
668 ref->action = action;
669 ref->is_head = 0;
670 ref->in_tree = 1;
671 ref->seq = seq;
672
673 full_ref = btrfs_delayed_node_to_tree_ref(ref);
674 full_ref->parent = parent;
675 full_ref->root = ref_root;
676 if (parent)
677 ref->type = BTRFS_SHARED_BLOCK_REF_KEY;
678 else
679 ref->type = BTRFS_TREE_BLOCK_REF_KEY;
680 full_ref->level = level;
681
682 trace_add_delayed_tree_ref(ref, full_ref, action);
683
684 ret = add_delayed_ref_tail_merge(trans, delayed_refs, head_ref, ref);
685
686 /*
687 * XXX: memory should be freed at the same level allocated.
688 * But bad practice is anywhere... Follow it now. Need cleanup.
689 */
690 if (ret > 0)
691 kmem_cache_free(btrfs_delayed_tree_ref_cachep, full_ref);
692 }
693
694 /*
695 * helper to insert a delayed data ref into the rbtree.
696 */
697 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)698 add_delayed_data_ref(struct btrfs_fs_info *fs_info,
699 struct btrfs_trans_handle *trans,
700 struct btrfs_delayed_ref_head *head_ref,
701 struct btrfs_delayed_ref_node *ref, u64 bytenr,
702 u64 num_bytes, u64 parent, u64 ref_root, u64 owner,
703 u64 offset, int action)
704 {
705 struct btrfs_delayed_data_ref *full_ref;
706 struct btrfs_delayed_ref_root *delayed_refs;
707 u64 seq = 0;
708 int ret;
709
710 if (action == BTRFS_ADD_DELAYED_EXTENT)
711 action = BTRFS_ADD_DELAYED_REF;
712
713 delayed_refs = &trans->transaction->delayed_refs;
714
715 if (is_fstree(ref_root))
716 seq = atomic64_read(&fs_info->tree_mod_seq);
717
718 /* first set the basic ref node struct up */
719 atomic_set(&ref->refs, 1);
720 ref->bytenr = bytenr;
721 ref->num_bytes = num_bytes;
722 ref->ref_mod = 1;
723 ref->action = action;
724 ref->is_head = 0;
725 ref->in_tree = 1;
726 ref->seq = seq;
727
728 full_ref = btrfs_delayed_node_to_data_ref(ref);
729 full_ref->parent = parent;
730 full_ref->root = ref_root;
731 if (parent)
732 ref->type = BTRFS_SHARED_DATA_REF_KEY;
733 else
734 ref->type = BTRFS_EXTENT_DATA_REF_KEY;
735
736 full_ref->objectid = owner;
737 full_ref->offset = offset;
738
739 trace_add_delayed_data_ref(ref, full_ref, action);
740
741 ret = add_delayed_ref_tail_merge(trans, delayed_refs, head_ref, ref);
742
743 if (ret > 0)
744 kmem_cache_free(btrfs_delayed_data_ref_cachep, full_ref);
745 }
746
747 /*
748 * add a delayed tree ref. This does all of the accounting required
749 * to make sure the delayed ref is eventually processed before this
750 * transaction commits.
751 */
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)752 int btrfs_add_delayed_tree_ref(struct btrfs_fs_info *fs_info,
753 struct btrfs_trans_handle *trans,
754 u64 bytenr, u64 num_bytes, u64 parent,
755 u64 ref_root, int level, int action,
756 struct btrfs_delayed_extent_op *extent_op)
757 {
758 struct btrfs_delayed_tree_ref *ref;
759 struct btrfs_delayed_ref_head *head_ref;
760 struct btrfs_delayed_ref_root *delayed_refs;
761 struct btrfs_qgroup_extent_record *record = NULL;
762
763 BUG_ON(extent_op && extent_op->is_data);
764 ref = kmem_cache_alloc(btrfs_delayed_tree_ref_cachep, GFP_NOFS);
765 if (!ref)
766 return -ENOMEM;
767
768 head_ref = kmem_cache_alloc(btrfs_delayed_ref_head_cachep, GFP_NOFS);
769 if (!head_ref)
770 goto free_ref;
771
772 if (fs_info->quota_enabled && is_fstree(ref_root)) {
773 record = kmalloc(sizeof(*record), GFP_NOFS);
774 if (!record)
775 goto free_head_ref;
776 }
777
778 head_ref->extent_op = extent_op;
779
780 delayed_refs = &trans->transaction->delayed_refs;
781 spin_lock(&delayed_refs->lock);
782
783 /*
784 * insert both the head node and the new ref without dropping
785 * the spin lock
786 */
787 head_ref = add_delayed_ref_head(fs_info, trans, &head_ref->node, record,
788 bytenr, num_bytes, 0, 0, action, 0);
789
790 add_delayed_tree_ref(fs_info, trans, head_ref, &ref->node, bytenr,
791 num_bytes, parent, ref_root, level, action);
792 spin_unlock(&delayed_refs->lock);
793
794 return 0;
795
796 free_head_ref:
797 kmem_cache_free(btrfs_delayed_ref_head_cachep, head_ref);
798 free_ref:
799 kmem_cache_free(btrfs_delayed_tree_ref_cachep, ref);
800
801 return -ENOMEM;
802 }
803
804 /*
805 * add a delayed data ref. it's similar to btrfs_add_delayed_tree_ref.
806 */
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)807 int btrfs_add_delayed_data_ref(struct btrfs_fs_info *fs_info,
808 struct btrfs_trans_handle *trans,
809 u64 bytenr, u64 num_bytes,
810 u64 parent, u64 ref_root,
811 u64 owner, u64 offset, u64 reserved, int action,
812 struct btrfs_delayed_extent_op *extent_op)
813 {
814 struct btrfs_delayed_data_ref *ref;
815 struct btrfs_delayed_ref_head *head_ref;
816 struct btrfs_delayed_ref_root *delayed_refs;
817 struct btrfs_qgroup_extent_record *record = NULL;
818
819 BUG_ON(extent_op && !extent_op->is_data);
820 ref = kmem_cache_alloc(btrfs_delayed_data_ref_cachep, GFP_NOFS);
821 if (!ref)
822 return -ENOMEM;
823
824 head_ref = kmem_cache_alloc(btrfs_delayed_ref_head_cachep, GFP_NOFS);
825 if (!head_ref) {
826 kmem_cache_free(btrfs_delayed_data_ref_cachep, ref);
827 return -ENOMEM;
828 }
829
830 if (fs_info->quota_enabled && is_fstree(ref_root)) {
831 record = kmalloc(sizeof(*record), GFP_NOFS);
832 if (!record) {
833 kmem_cache_free(btrfs_delayed_data_ref_cachep, ref);
834 kmem_cache_free(btrfs_delayed_ref_head_cachep,
835 head_ref);
836 return -ENOMEM;
837 }
838 }
839
840 head_ref->extent_op = extent_op;
841
842 delayed_refs = &trans->transaction->delayed_refs;
843 spin_lock(&delayed_refs->lock);
844
845 /*
846 * insert both the head node and the new ref without dropping
847 * the spin lock
848 */
849 head_ref = add_delayed_ref_head(fs_info, trans, &head_ref->node, record,
850 bytenr, num_bytes, ref_root, reserved,
851 action, 1);
852
853 add_delayed_data_ref(fs_info, trans, head_ref, &ref->node, bytenr,
854 num_bytes, parent, ref_root, owner, offset,
855 action);
856 spin_unlock(&delayed_refs->lock);
857
858 return 0;
859 }
860
btrfs_add_delayed_qgroup_reserve(struct btrfs_fs_info * fs_info,struct btrfs_trans_handle * trans,u64 ref_root,u64 bytenr,u64 num_bytes)861 int btrfs_add_delayed_qgroup_reserve(struct btrfs_fs_info *fs_info,
862 struct btrfs_trans_handle *trans,
863 u64 ref_root, u64 bytenr, u64 num_bytes)
864 {
865 struct btrfs_delayed_ref_root *delayed_refs;
866 struct btrfs_delayed_ref_head *ref_head;
867 int ret = 0;
868
869 if (!fs_info->quota_enabled || !is_fstree(ref_root))
870 return 0;
871
872 delayed_refs = &trans->transaction->delayed_refs;
873
874 spin_lock(&delayed_refs->lock);
875 ref_head = find_ref_head(&delayed_refs->href_root, bytenr, 0);
876 if (!ref_head) {
877 ret = -ENOENT;
878 goto out;
879 }
880 WARN_ON(ref_head->qgroup_reserved || ref_head->qgroup_ref_root);
881 ref_head->qgroup_ref_root = ref_root;
882 ref_head->qgroup_reserved = num_bytes;
883 out:
884 spin_unlock(&delayed_refs->lock);
885 return ret;
886 }
887
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)888 int btrfs_add_delayed_extent_op(struct btrfs_fs_info *fs_info,
889 struct btrfs_trans_handle *trans,
890 u64 bytenr, u64 num_bytes,
891 struct btrfs_delayed_extent_op *extent_op)
892 {
893 struct btrfs_delayed_ref_head *head_ref;
894 struct btrfs_delayed_ref_root *delayed_refs;
895
896 head_ref = kmem_cache_alloc(btrfs_delayed_ref_head_cachep, GFP_NOFS);
897 if (!head_ref)
898 return -ENOMEM;
899
900 head_ref->extent_op = extent_op;
901
902 delayed_refs = &trans->transaction->delayed_refs;
903 spin_lock(&delayed_refs->lock);
904
905 add_delayed_ref_head(fs_info, trans, &head_ref->node, NULL, bytenr,
906 num_bytes, 0, 0, BTRFS_UPDATE_DELAYED_HEAD,
907 extent_op->is_data);
908
909 spin_unlock(&delayed_refs->lock);
910 return 0;
911 }
912
913 /*
914 * this does a simple search for the head node for a given extent.
915 * It must be called with the delayed ref spinlock held, and it returns
916 * the head node if any where found, or NULL if not.
917 */
918 struct btrfs_delayed_ref_head *
btrfs_find_delayed_ref_head(struct btrfs_trans_handle * trans,u64 bytenr)919 btrfs_find_delayed_ref_head(struct btrfs_trans_handle *trans, u64 bytenr)
920 {
921 struct btrfs_delayed_ref_root *delayed_refs;
922
923 delayed_refs = &trans->transaction->delayed_refs;
924 return find_ref_head(&delayed_refs->href_root, bytenr, 0);
925 }
926
btrfs_delayed_ref_exit(void)927 void btrfs_delayed_ref_exit(void)
928 {
929 if (btrfs_delayed_ref_head_cachep)
930 kmem_cache_destroy(btrfs_delayed_ref_head_cachep);
931 if (btrfs_delayed_tree_ref_cachep)
932 kmem_cache_destroy(btrfs_delayed_tree_ref_cachep);
933 if (btrfs_delayed_data_ref_cachep)
934 kmem_cache_destroy(btrfs_delayed_data_ref_cachep);
935 if (btrfs_delayed_extent_op_cachep)
936 kmem_cache_destroy(btrfs_delayed_extent_op_cachep);
937 }
938
btrfs_delayed_ref_init(void)939 int btrfs_delayed_ref_init(void)
940 {
941 btrfs_delayed_ref_head_cachep = kmem_cache_create(
942 "btrfs_delayed_ref_head",
943 sizeof(struct btrfs_delayed_ref_head), 0,
944 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
945 if (!btrfs_delayed_ref_head_cachep)
946 goto fail;
947
948 btrfs_delayed_tree_ref_cachep = kmem_cache_create(
949 "btrfs_delayed_tree_ref",
950 sizeof(struct btrfs_delayed_tree_ref), 0,
951 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
952 if (!btrfs_delayed_tree_ref_cachep)
953 goto fail;
954
955 btrfs_delayed_data_ref_cachep = kmem_cache_create(
956 "btrfs_delayed_data_ref",
957 sizeof(struct btrfs_delayed_data_ref), 0,
958 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
959 if (!btrfs_delayed_data_ref_cachep)
960 goto fail;
961
962 btrfs_delayed_extent_op_cachep = kmem_cache_create(
963 "btrfs_delayed_extent_op",
964 sizeof(struct btrfs_delayed_extent_op), 0,
965 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
966 if (!btrfs_delayed_extent_op_cachep)
967 goto fail;
968
969 return 0;
970 fail:
971 btrfs_delayed_ref_exit();
972 return -ENOMEM;
973 }
974