f26f38ccd1942bb8c27fddb05d25995c9a4e3e1b
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / btrfs / delayed-inode.c
1 /*
2 * Copyright (C) 2011 Fujitsu. All rights reserved.
3 * Written by Miao Xie <miaox@cn.fujitsu.com>
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public
7 * License v2 as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public
15 * License along with this program; if not, write to the
16 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
17 * Boston, MA 021110-1307, USA.
18 */
19
20 #include <linux/slab.h>
21 #include "delayed-inode.h"
22 #include "disk-io.h"
23 #include "transaction.h"
24
25 #define BTRFS_DELAYED_WRITEBACK 512
26 #define BTRFS_DELAYED_BACKGROUND 128
27 #define BTRFS_DELAYED_BATCH 16
28
29 static struct kmem_cache *delayed_node_cache;
30
31 int __init btrfs_delayed_inode_init(void)
32 {
33 delayed_node_cache = kmem_cache_create("btrfs_delayed_node",
34 sizeof(struct btrfs_delayed_node),
35 0,
36 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
37 NULL);
38 if (!delayed_node_cache)
39 return -ENOMEM;
40 return 0;
41 }
42
43 void btrfs_delayed_inode_exit(void)
44 {
45 if (delayed_node_cache)
46 kmem_cache_destroy(delayed_node_cache);
47 }
48
49 static inline void btrfs_init_delayed_node(
50 struct btrfs_delayed_node *delayed_node,
51 struct btrfs_root *root, u64 inode_id)
52 {
53 delayed_node->root = root;
54 delayed_node->inode_id = inode_id;
55 atomic_set(&delayed_node->refs, 0);
56 delayed_node->count = 0;
57 delayed_node->in_list = 0;
58 delayed_node->inode_dirty = 0;
59 delayed_node->ins_root = RB_ROOT;
60 delayed_node->del_root = RB_ROOT;
61 mutex_init(&delayed_node->mutex);
62 delayed_node->index_cnt = 0;
63 INIT_LIST_HEAD(&delayed_node->n_list);
64 INIT_LIST_HEAD(&delayed_node->p_list);
65 delayed_node->bytes_reserved = 0;
66 memset(&delayed_node->inode_item, 0, sizeof(delayed_node->inode_item));
67 }
68
69 static inline int btrfs_is_continuous_delayed_item(
70 struct btrfs_delayed_item *item1,
71 struct btrfs_delayed_item *item2)
72 {
73 if (item1->key.type == BTRFS_DIR_INDEX_KEY &&
74 item1->key.objectid == item2->key.objectid &&
75 item1->key.type == item2->key.type &&
76 item1->key.offset + 1 == item2->key.offset)
77 return 1;
78 return 0;
79 }
80
81 static inline struct btrfs_delayed_root *btrfs_get_delayed_root(
82 struct btrfs_root *root)
83 {
84 return root->fs_info->delayed_root;
85 }
86
87 static struct btrfs_delayed_node *btrfs_get_delayed_node(struct inode *inode)
88 {
89 struct btrfs_inode *btrfs_inode = BTRFS_I(inode);
90 struct btrfs_root *root = btrfs_inode->root;
91 u64 ino = btrfs_ino(inode);
92 struct btrfs_delayed_node *node;
93
94 node = ACCESS_ONCE(btrfs_inode->delayed_node);
95 if (node) {
96 atomic_inc(&node->refs);
97 return node;
98 }
99
100 spin_lock(&root->inode_lock);
101 node = radix_tree_lookup(&root->delayed_nodes_tree, ino);
102 if (node) {
103 if (btrfs_inode->delayed_node) {
104 atomic_inc(&node->refs); /* can be accessed */
105 BUG_ON(btrfs_inode->delayed_node != node);
106 spin_unlock(&root->inode_lock);
107 return node;
108 }
109 btrfs_inode->delayed_node = node;
110 atomic_inc(&node->refs); /* can be accessed */
111 atomic_inc(&node->refs); /* cached in the inode */
112 spin_unlock(&root->inode_lock);
113 return node;
114 }
115 spin_unlock(&root->inode_lock);
116
117 return NULL;
118 }
119
120 /* Will return either the node or PTR_ERR(-ENOMEM) */
121 static struct btrfs_delayed_node *btrfs_get_or_create_delayed_node(
122 struct inode *inode)
123 {
124 struct btrfs_delayed_node *node;
125 struct btrfs_inode *btrfs_inode = BTRFS_I(inode);
126 struct btrfs_root *root = btrfs_inode->root;
127 u64 ino = btrfs_ino(inode);
128 int ret;
129
130 again:
131 node = btrfs_get_delayed_node(inode);
132 if (node)
133 return node;
134
135 node = kmem_cache_alloc(delayed_node_cache, GFP_NOFS);
136 if (!node)
137 return ERR_PTR(-ENOMEM);
138 btrfs_init_delayed_node(node, root, ino);
139
140 atomic_inc(&node->refs); /* cached in the btrfs inode */
141 atomic_inc(&node->refs); /* can be accessed */
142
143 ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
144 if (ret) {
145 kmem_cache_free(delayed_node_cache, node);
146 return ERR_PTR(ret);
147 }
148
149 spin_lock(&root->inode_lock);
150 ret = radix_tree_insert(&root->delayed_nodes_tree, ino, node);
151 if (ret == -EEXIST) {
152 kmem_cache_free(delayed_node_cache, node);
153 spin_unlock(&root->inode_lock);
154 radix_tree_preload_end();
155 goto again;
156 }
157 btrfs_inode->delayed_node = node;
158 spin_unlock(&root->inode_lock);
159 radix_tree_preload_end();
160
161 return node;
162 }
163
164 /*
165 * Call it when holding delayed_node->mutex
166 *
167 * If mod = 1, add this node into the prepared list.
168 */
169 static void btrfs_queue_delayed_node(struct btrfs_delayed_root *root,
170 struct btrfs_delayed_node *node,
171 int mod)
172 {
173 spin_lock(&root->lock);
174 if (node->in_list) {
175 if (!list_empty(&node->p_list))
176 list_move_tail(&node->p_list, &root->prepare_list);
177 else if (mod)
178 list_add_tail(&node->p_list, &root->prepare_list);
179 } else {
180 list_add_tail(&node->n_list, &root->node_list);
181 list_add_tail(&node->p_list, &root->prepare_list);
182 atomic_inc(&node->refs); /* inserted into list */
183 root->nodes++;
184 node->in_list = 1;
185 }
186 spin_unlock(&root->lock);
187 }
188
189 /* Call it when holding delayed_node->mutex */
190 static void btrfs_dequeue_delayed_node(struct btrfs_delayed_root *root,
191 struct btrfs_delayed_node *node)
192 {
193 spin_lock(&root->lock);
194 if (node->in_list) {
195 root->nodes--;
196 atomic_dec(&node->refs); /* not in the list */
197 list_del_init(&node->n_list);
198 if (!list_empty(&node->p_list))
199 list_del_init(&node->p_list);
200 node->in_list = 0;
201 }
202 spin_unlock(&root->lock);
203 }
204
205 static struct btrfs_delayed_node *btrfs_first_delayed_node(
206 struct btrfs_delayed_root *delayed_root)
207 {
208 struct list_head *p;
209 struct btrfs_delayed_node *node = NULL;
210
211 spin_lock(&delayed_root->lock);
212 if (list_empty(&delayed_root->node_list))
213 goto out;
214
215 p = delayed_root->node_list.next;
216 node = list_entry(p, struct btrfs_delayed_node, n_list);
217 atomic_inc(&node->refs);
218 out:
219 spin_unlock(&delayed_root->lock);
220
221 return node;
222 }
223
224 static struct btrfs_delayed_node *btrfs_next_delayed_node(
225 struct btrfs_delayed_node *node)
226 {
227 struct btrfs_delayed_root *delayed_root;
228 struct list_head *p;
229 struct btrfs_delayed_node *next = NULL;
230
231 delayed_root = node->root->fs_info->delayed_root;
232 spin_lock(&delayed_root->lock);
233 if (!node->in_list) { /* not in the list */
234 if (list_empty(&delayed_root->node_list))
235 goto out;
236 p = delayed_root->node_list.next;
237 } else if (list_is_last(&node->n_list, &delayed_root->node_list))
238 goto out;
239 else
240 p = node->n_list.next;
241
242 next = list_entry(p, struct btrfs_delayed_node, n_list);
243 atomic_inc(&next->refs);
244 out:
245 spin_unlock(&delayed_root->lock);
246
247 return next;
248 }
249
250 static void __btrfs_release_delayed_node(
251 struct btrfs_delayed_node *delayed_node,
252 int mod)
253 {
254 struct btrfs_delayed_root *delayed_root;
255
256 if (!delayed_node)
257 return;
258
259 delayed_root = delayed_node->root->fs_info->delayed_root;
260
261 mutex_lock(&delayed_node->mutex);
262 if (delayed_node->count)
263 btrfs_queue_delayed_node(delayed_root, delayed_node, mod);
264 else
265 btrfs_dequeue_delayed_node(delayed_root, delayed_node);
266 mutex_unlock(&delayed_node->mutex);
267
268 if (atomic_dec_and_test(&delayed_node->refs)) {
269 struct btrfs_root *root = delayed_node->root;
270 spin_lock(&root->inode_lock);
271 if (atomic_read(&delayed_node->refs) == 0) {
272 radix_tree_delete(&root->delayed_nodes_tree,
273 delayed_node->inode_id);
274 kmem_cache_free(delayed_node_cache, delayed_node);
275 }
276 spin_unlock(&root->inode_lock);
277 }
278 }
279
280 static inline void btrfs_release_delayed_node(struct btrfs_delayed_node *node)
281 {
282 __btrfs_release_delayed_node(node, 0);
283 }
284
285 static struct btrfs_delayed_node *btrfs_first_prepared_delayed_node(
286 struct btrfs_delayed_root *delayed_root)
287 {
288 struct list_head *p;
289 struct btrfs_delayed_node *node = NULL;
290
291 spin_lock(&delayed_root->lock);
292 if (list_empty(&delayed_root->prepare_list))
293 goto out;
294
295 p = delayed_root->prepare_list.next;
296 list_del_init(p);
297 node = list_entry(p, struct btrfs_delayed_node, p_list);
298 atomic_inc(&node->refs);
299 out:
300 spin_unlock(&delayed_root->lock);
301
302 return node;
303 }
304
305 static inline void btrfs_release_prepared_delayed_node(
306 struct btrfs_delayed_node *node)
307 {
308 __btrfs_release_delayed_node(node, 1);
309 }
310
311 static struct btrfs_delayed_item *btrfs_alloc_delayed_item(u32 data_len)
312 {
313 struct btrfs_delayed_item *item;
314 item = kmalloc(sizeof(*item) + data_len, GFP_NOFS);
315 if (item) {
316 item->data_len = data_len;
317 item->ins_or_del = 0;
318 item->bytes_reserved = 0;
319 item->delayed_node = NULL;
320 atomic_set(&item->refs, 1);
321 }
322 return item;
323 }
324
325 /*
326 * __btrfs_lookup_delayed_item - look up the delayed item by key
327 * @delayed_node: pointer to the delayed node
328 * @key: the key to look up
329 * @prev: used to store the prev item if the right item isn't found
330 * @next: used to store the next item if the right item isn't found
331 *
332 * Note: if we don't find the right item, we will return the prev item and
333 * the next item.
334 */
335 static struct btrfs_delayed_item *__btrfs_lookup_delayed_item(
336 struct rb_root *root,
337 struct btrfs_key *key,
338 struct btrfs_delayed_item **prev,
339 struct btrfs_delayed_item **next)
340 {
341 struct rb_node *node, *prev_node = NULL;
342 struct btrfs_delayed_item *delayed_item = NULL;
343 int ret = 0;
344
345 node = root->rb_node;
346
347 while (node) {
348 delayed_item = rb_entry(node, struct btrfs_delayed_item,
349 rb_node);
350 prev_node = node;
351 ret = btrfs_comp_cpu_keys(&delayed_item->key, key);
352 if (ret < 0)
353 node = node->rb_right;
354 else if (ret > 0)
355 node = node->rb_left;
356 else
357 return delayed_item;
358 }
359
360 if (prev) {
361 if (!prev_node)
362 *prev = NULL;
363 else if (ret < 0)
364 *prev = delayed_item;
365 else if ((node = rb_prev(prev_node)) != NULL) {
366 *prev = rb_entry(node, struct btrfs_delayed_item,
367 rb_node);
368 } else
369 *prev = NULL;
370 }
371
372 if (next) {
373 if (!prev_node)
374 *next = NULL;
375 else if (ret > 0)
376 *next = delayed_item;
377 else if ((node = rb_next(prev_node)) != NULL) {
378 *next = rb_entry(node, struct btrfs_delayed_item,
379 rb_node);
380 } else
381 *next = NULL;
382 }
383 return NULL;
384 }
385
386 static struct btrfs_delayed_item *__btrfs_lookup_delayed_insertion_item(
387 struct btrfs_delayed_node *delayed_node,
388 struct btrfs_key *key)
389 {
390 struct btrfs_delayed_item *item;
391
392 item = __btrfs_lookup_delayed_item(&delayed_node->ins_root, key,
393 NULL, NULL);
394 return item;
395 }
396
397 static int __btrfs_add_delayed_item(struct btrfs_delayed_node *delayed_node,
398 struct btrfs_delayed_item *ins,
399 int action)
400 {
401 struct rb_node **p, *node;
402 struct rb_node *parent_node = NULL;
403 struct rb_root *root;
404 struct btrfs_delayed_item *item;
405 int cmp;
406
407 if (action == BTRFS_DELAYED_INSERTION_ITEM)
408 root = &delayed_node->ins_root;
409 else if (action == BTRFS_DELAYED_DELETION_ITEM)
410 root = &delayed_node->del_root;
411 else
412 BUG();
413 p = &root->rb_node;
414 node = &ins->rb_node;
415
416 while (*p) {
417 parent_node = *p;
418 item = rb_entry(parent_node, struct btrfs_delayed_item,
419 rb_node);
420
421 cmp = btrfs_comp_cpu_keys(&item->key, &ins->key);
422 if (cmp < 0)
423 p = &(*p)->rb_right;
424 else if (cmp > 0)
425 p = &(*p)->rb_left;
426 else
427 return -EEXIST;
428 }
429
430 rb_link_node(node, parent_node, p);
431 rb_insert_color(node, root);
432 ins->delayed_node = delayed_node;
433 ins->ins_or_del = action;
434
435 if (ins->key.type == BTRFS_DIR_INDEX_KEY &&
436 action == BTRFS_DELAYED_INSERTION_ITEM &&
437 ins->key.offset >= delayed_node->index_cnt)
438 delayed_node->index_cnt = ins->key.offset + 1;
439
440 delayed_node->count++;
441 atomic_inc(&delayed_node->root->fs_info->delayed_root->items);
442 return 0;
443 }
444
445 static int __btrfs_add_delayed_insertion_item(struct btrfs_delayed_node *node,
446 struct btrfs_delayed_item *item)
447 {
448 return __btrfs_add_delayed_item(node, item,
449 BTRFS_DELAYED_INSERTION_ITEM);
450 }
451
452 static int __btrfs_add_delayed_deletion_item(struct btrfs_delayed_node *node,
453 struct btrfs_delayed_item *item)
454 {
455 return __btrfs_add_delayed_item(node, item,
456 BTRFS_DELAYED_DELETION_ITEM);
457 }
458
459 static void finish_one_item(struct btrfs_delayed_root *delayed_root)
460 {
461 int seq = atomic_inc_return(&delayed_root->items_seq);
462 if ((atomic_dec_return(&delayed_root->items) <
463 BTRFS_DELAYED_BACKGROUND || seq % BTRFS_DELAYED_BATCH == 0) &&
464 waitqueue_active(&delayed_root->wait))
465 wake_up(&delayed_root->wait);
466 }
467
468 static void __btrfs_remove_delayed_item(struct btrfs_delayed_item *delayed_item)
469 {
470 struct rb_root *root;
471 struct btrfs_delayed_root *delayed_root;
472
473 delayed_root = delayed_item->delayed_node->root->fs_info->delayed_root;
474
475 BUG_ON(!delayed_root);
476 BUG_ON(delayed_item->ins_or_del != BTRFS_DELAYED_DELETION_ITEM &&
477 delayed_item->ins_or_del != BTRFS_DELAYED_INSERTION_ITEM);
478
479 if (delayed_item->ins_or_del == BTRFS_DELAYED_INSERTION_ITEM)
480 root = &delayed_item->delayed_node->ins_root;
481 else
482 root = &delayed_item->delayed_node->del_root;
483
484 rb_erase(&delayed_item->rb_node, root);
485 delayed_item->delayed_node->count--;
486
487 finish_one_item(delayed_root);
488 }
489
490 static void btrfs_release_delayed_item(struct btrfs_delayed_item *item)
491 {
492 if (item) {
493 __btrfs_remove_delayed_item(item);
494 if (atomic_dec_and_test(&item->refs))
495 kfree(item);
496 }
497 }
498
499 static struct btrfs_delayed_item *__btrfs_first_delayed_insertion_item(
500 struct btrfs_delayed_node *delayed_node)
501 {
502 struct rb_node *p;
503 struct btrfs_delayed_item *item = NULL;
504
505 p = rb_first(&delayed_node->ins_root);
506 if (p)
507 item = rb_entry(p, struct btrfs_delayed_item, rb_node);
508
509 return item;
510 }
511
512 static struct btrfs_delayed_item *__btrfs_first_delayed_deletion_item(
513 struct btrfs_delayed_node *delayed_node)
514 {
515 struct rb_node *p;
516 struct btrfs_delayed_item *item = NULL;
517
518 p = rb_first(&delayed_node->del_root);
519 if (p)
520 item = rb_entry(p, struct btrfs_delayed_item, rb_node);
521
522 return item;
523 }
524
525 static struct btrfs_delayed_item *__btrfs_next_delayed_item(
526 struct btrfs_delayed_item *item)
527 {
528 struct rb_node *p;
529 struct btrfs_delayed_item *next = NULL;
530
531 p = rb_next(&item->rb_node);
532 if (p)
533 next = rb_entry(p, struct btrfs_delayed_item, rb_node);
534
535 return next;
536 }
537
538 static inline struct btrfs_root *btrfs_get_fs_root(struct btrfs_root *root,
539 u64 root_id)
540 {
541 struct btrfs_key root_key;
542
543 if (root->objectid == root_id)
544 return root;
545
546 root_key.objectid = root_id;
547 root_key.type = BTRFS_ROOT_ITEM_KEY;
548 root_key.offset = (u64)-1;
549 return btrfs_read_fs_root_no_name(root->fs_info, &root_key);
550 }
551
552 static int btrfs_delayed_item_reserve_metadata(struct btrfs_trans_handle *trans,
553 struct btrfs_root *root,
554 struct btrfs_delayed_item *item)
555 {
556 struct btrfs_block_rsv *src_rsv;
557 struct btrfs_block_rsv *dst_rsv;
558 u64 num_bytes;
559 int ret;
560
561 if (!trans->bytes_reserved)
562 return 0;
563
564 src_rsv = trans->block_rsv;
565 dst_rsv = &root->fs_info->delayed_block_rsv;
566
567 num_bytes = btrfs_calc_trans_metadata_size(root, 1);
568 ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes);
569 if (!ret) {
570 trace_btrfs_space_reservation(root->fs_info, "delayed_item",
571 item->key.objectid,
572 num_bytes, 1);
573 item->bytes_reserved = num_bytes;
574 }
575
576 return ret;
577 }
578
579 static void btrfs_delayed_item_release_metadata(struct btrfs_root *root,
580 struct btrfs_delayed_item *item)
581 {
582 struct btrfs_block_rsv *rsv;
583
584 if (!item->bytes_reserved)
585 return;
586
587 rsv = &root->fs_info->delayed_block_rsv;
588 trace_btrfs_space_reservation(root->fs_info, "delayed_item",
589 item->key.objectid, item->bytes_reserved,
590 0);
591 btrfs_block_rsv_release(root, rsv,
592 item->bytes_reserved);
593 }
594
595 static int btrfs_delayed_inode_reserve_metadata(
596 struct btrfs_trans_handle *trans,
597 struct btrfs_root *root,
598 struct inode *inode,
599 struct btrfs_delayed_node *node)
600 {
601 struct btrfs_block_rsv *src_rsv;
602 struct btrfs_block_rsv *dst_rsv;
603 u64 num_bytes;
604 int ret;
605 bool release = false;
606
607 src_rsv = trans->block_rsv;
608 dst_rsv = &root->fs_info->delayed_block_rsv;
609
610 num_bytes = btrfs_calc_trans_metadata_size(root, 1);
611
612 /*
613 * btrfs_dirty_inode will update the inode under btrfs_join_transaction
614 * which doesn't reserve space for speed. This is a problem since we
615 * still need to reserve space for this update, so try to reserve the
616 * space.
617 *
618 * Now if src_rsv == delalloc_block_rsv we'll let it just steal since
619 * we're accounted for.
620 */
621 if (!src_rsv || (!trans->bytes_reserved &&
622 src_rsv->type != BTRFS_BLOCK_RSV_DELALLOC)) {
623 ret = btrfs_block_rsv_add(root, dst_rsv, num_bytes,
624 BTRFS_RESERVE_NO_FLUSH);
625 /*
626 * Since we're under a transaction reserve_metadata_bytes could
627 * try to commit the transaction which will make it return
628 * EAGAIN to make us stop the transaction we have, so return
629 * ENOSPC instead so that btrfs_dirty_inode knows what to do.
630 */
631 if (ret == -EAGAIN)
632 ret = -ENOSPC;
633 if (!ret) {
634 node->bytes_reserved = num_bytes;
635 trace_btrfs_space_reservation(root->fs_info,
636 "delayed_inode",
637 btrfs_ino(inode),
638 num_bytes, 1);
639 }
640 return ret;
641 } else if (src_rsv->type == BTRFS_BLOCK_RSV_DELALLOC) {
642 spin_lock(&BTRFS_I(inode)->lock);
643 if (test_and_clear_bit(BTRFS_INODE_DELALLOC_META_RESERVED,
644 &BTRFS_I(inode)->runtime_flags)) {
645 spin_unlock(&BTRFS_I(inode)->lock);
646 release = true;
647 goto migrate;
648 }
649 spin_unlock(&BTRFS_I(inode)->lock);
650
651 /* Ok we didn't have space pre-reserved. This shouldn't happen
652 * too often but it can happen if we do delalloc to an existing
653 * inode which gets dirtied because of the time update, and then
654 * isn't touched again until after the transaction commits and
655 * then we try to write out the data. First try to be nice and
656 * reserve something strictly for us. If not be a pain and try
657 * to steal from the delalloc block rsv.
658 */
659 ret = btrfs_block_rsv_add(root, dst_rsv, num_bytes,
660 BTRFS_RESERVE_NO_FLUSH);
661 if (!ret)
662 goto out;
663
664 ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes);
665 if (!ret)
666 goto out;
667
668 /*
669 * Ok this is a problem, let's just steal from the global rsv
670 * since this really shouldn't happen that often.
671 */
672 WARN_ON(1);
673 ret = btrfs_block_rsv_migrate(&root->fs_info->global_block_rsv,
674 dst_rsv, num_bytes);
675 goto out;
676 }
677
678 migrate:
679 ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes);
680
681 out:
682 /*
683 * Migrate only takes a reservation, it doesn't touch the size of the
684 * block_rsv. This is to simplify people who don't normally have things
685 * migrated from their block rsv. If they go to release their
686 * reservation, that will decrease the size as well, so if migrate
687 * reduced size we'd end up with a negative size. But for the
688 * delalloc_meta_reserved stuff we will only know to drop 1 reservation,
689 * but we could in fact do this reserve/migrate dance several times
690 * between the time we did the original reservation and we'd clean it
691 * up. So to take care of this, release the space for the meta
692 * reservation here. I think it may be time for a documentation page on
693 * how block rsvs. work.
694 */
695 if (!ret) {
696 trace_btrfs_space_reservation(root->fs_info, "delayed_inode",
697 btrfs_ino(inode), num_bytes, 1);
698 node->bytes_reserved = num_bytes;
699 }
700
701 if (release) {
702 trace_btrfs_space_reservation(root->fs_info, "delalloc",
703 btrfs_ino(inode), num_bytes, 0);
704 btrfs_block_rsv_release(root, src_rsv, num_bytes);
705 }
706
707 return ret;
708 }
709
710 static void btrfs_delayed_inode_release_metadata(struct btrfs_root *root,
711 struct btrfs_delayed_node *node)
712 {
713 struct btrfs_block_rsv *rsv;
714
715 if (!node->bytes_reserved)
716 return;
717
718 rsv = &root->fs_info->delayed_block_rsv;
719 trace_btrfs_space_reservation(root->fs_info, "delayed_inode",
720 node->inode_id, node->bytes_reserved, 0);
721 btrfs_block_rsv_release(root, rsv,
722 node->bytes_reserved);
723 node->bytes_reserved = 0;
724 }
725
726 /*
727 * This helper will insert some continuous items into the same leaf according
728 * to the free space of the leaf.
729 */
730 static int btrfs_batch_insert_items(struct btrfs_root *root,
731 struct btrfs_path *path,
732 struct btrfs_delayed_item *item)
733 {
734 struct btrfs_delayed_item *curr, *next;
735 int free_space;
736 int total_data_size = 0, total_size = 0;
737 struct extent_buffer *leaf;
738 char *data_ptr;
739 struct btrfs_key *keys;
740 u32 *data_size;
741 struct list_head head;
742 int slot;
743 int nitems;
744 int i;
745 int ret = 0;
746
747 BUG_ON(!path->nodes[0]);
748
749 leaf = path->nodes[0];
750 free_space = btrfs_leaf_free_space(root, leaf);
751 INIT_LIST_HEAD(&head);
752
753 next = item;
754 nitems = 0;
755
756 /*
757 * count the number of the continuous items that we can insert in batch
758 */
759 while (total_size + next->data_len + sizeof(struct btrfs_item) <=
760 free_space) {
761 total_data_size += next->data_len;
762 total_size += next->data_len + sizeof(struct btrfs_item);
763 list_add_tail(&next->tree_list, &head);
764 nitems++;
765
766 curr = next;
767 next = __btrfs_next_delayed_item(curr);
768 if (!next)
769 break;
770
771 if (!btrfs_is_continuous_delayed_item(curr, next))
772 break;
773 }
774
775 if (!nitems) {
776 ret = 0;
777 goto out;
778 }
779
780 /*
781 * we need allocate some memory space, but it might cause the task
782 * to sleep, so we set all locked nodes in the path to blocking locks
783 * first.
784 */
785 btrfs_set_path_blocking(path);
786
787 keys = kmalloc(sizeof(struct btrfs_key) * nitems, GFP_NOFS);
788 if (!keys) {
789 ret = -ENOMEM;
790 goto out;
791 }
792
793 data_size = kmalloc(sizeof(u32) * nitems, GFP_NOFS);
794 if (!data_size) {
795 ret = -ENOMEM;
796 goto error;
797 }
798
799 /* get keys of all the delayed items */
800 i = 0;
801 list_for_each_entry(next, &head, tree_list) {
802 keys[i] = next->key;
803 data_size[i] = next->data_len;
804 i++;
805 }
806
807 /* reset all the locked nodes in the patch to spinning locks. */
808 btrfs_clear_path_blocking(path, NULL, 0);
809
810 /* insert the keys of the items */
811 setup_items_for_insert(root, path, keys, data_size,
812 total_data_size, total_size, nitems);
813
814 /* insert the dir index items */
815 slot = path->slots[0];
816 list_for_each_entry_safe(curr, next, &head, tree_list) {
817 data_ptr = btrfs_item_ptr(leaf, slot, char);
818 write_extent_buffer(leaf, &curr->data,
819 (unsigned long)data_ptr,
820 curr->data_len);
821 slot++;
822
823 btrfs_delayed_item_release_metadata(root, curr);
824
825 list_del(&curr->tree_list);
826 btrfs_release_delayed_item(curr);
827 }
828
829 error:
830 kfree(data_size);
831 kfree(keys);
832 out:
833 return ret;
834 }
835
836 /*
837 * This helper can just do simple insertion that needn't extend item for new
838 * data, such as directory name index insertion, inode insertion.
839 */
840 static int btrfs_insert_delayed_item(struct btrfs_trans_handle *trans,
841 struct btrfs_root *root,
842 struct btrfs_path *path,
843 struct btrfs_delayed_item *delayed_item)
844 {
845 struct extent_buffer *leaf;
846 char *ptr;
847 int ret;
848
849 ret = btrfs_insert_empty_item(trans, root, path, &delayed_item->key,
850 delayed_item->data_len);
851 if (ret < 0 && ret != -EEXIST)
852 return ret;
853
854 leaf = path->nodes[0];
855
856 ptr = btrfs_item_ptr(leaf, path->slots[0], char);
857
858 write_extent_buffer(leaf, delayed_item->data, (unsigned long)ptr,
859 delayed_item->data_len);
860 btrfs_mark_buffer_dirty(leaf);
861
862 btrfs_delayed_item_release_metadata(root, delayed_item);
863 return 0;
864 }
865
866 /*
867 * we insert an item first, then if there are some continuous items, we try
868 * to insert those items into the same leaf.
869 */
870 static int btrfs_insert_delayed_items(struct btrfs_trans_handle *trans,
871 struct btrfs_path *path,
872 struct btrfs_root *root,
873 struct btrfs_delayed_node *node)
874 {
875 struct btrfs_delayed_item *curr, *prev;
876 int ret = 0;
877
878 do_again:
879 mutex_lock(&node->mutex);
880 curr = __btrfs_first_delayed_insertion_item(node);
881 if (!curr)
882 goto insert_end;
883
884 ret = btrfs_insert_delayed_item(trans, root, path, curr);
885 if (ret < 0) {
886 btrfs_release_path(path);
887 goto insert_end;
888 }
889
890 prev = curr;
891 curr = __btrfs_next_delayed_item(prev);
892 if (curr && btrfs_is_continuous_delayed_item(prev, curr)) {
893 /* insert the continuous items into the same leaf */
894 path->slots[0]++;
895 btrfs_batch_insert_items(root, path, curr);
896 }
897 btrfs_release_delayed_item(prev);
898 btrfs_mark_buffer_dirty(path->nodes[0]);
899
900 btrfs_release_path(path);
901 mutex_unlock(&node->mutex);
902 goto do_again;
903
904 insert_end:
905 mutex_unlock(&node->mutex);
906 return ret;
907 }
908
909 static int btrfs_batch_delete_items(struct btrfs_trans_handle *trans,
910 struct btrfs_root *root,
911 struct btrfs_path *path,
912 struct btrfs_delayed_item *item)
913 {
914 struct btrfs_delayed_item *curr, *next;
915 struct extent_buffer *leaf;
916 struct btrfs_key key;
917 struct list_head head;
918 int nitems, i, last_item;
919 int ret = 0;
920
921 BUG_ON(!path->nodes[0]);
922
923 leaf = path->nodes[0];
924
925 i = path->slots[0];
926 last_item = btrfs_header_nritems(leaf) - 1;
927 if (i > last_item)
928 return -ENOENT; /* FIXME: Is errno suitable? */
929
930 next = item;
931 INIT_LIST_HEAD(&head);
932 btrfs_item_key_to_cpu(leaf, &key, i);
933 nitems = 0;
934 /*
935 * count the number of the dir index items that we can delete in batch
936 */
937 while (btrfs_comp_cpu_keys(&next->key, &key) == 0) {
938 list_add_tail(&next->tree_list, &head);
939 nitems++;
940
941 curr = next;
942 next = __btrfs_next_delayed_item(curr);
943 if (!next)
944 break;
945
946 if (!btrfs_is_continuous_delayed_item(curr, next))
947 break;
948
949 i++;
950 if (i > last_item)
951 break;
952 btrfs_item_key_to_cpu(leaf, &key, i);
953 }
954
955 if (!nitems)
956 return 0;
957
958 ret = btrfs_del_items(trans, root, path, path->slots[0], nitems);
959 if (ret)
960 goto out;
961
962 list_for_each_entry_safe(curr, next, &head, tree_list) {
963 btrfs_delayed_item_release_metadata(root, curr);
964 list_del(&curr->tree_list);
965 btrfs_release_delayed_item(curr);
966 }
967
968 out:
969 return ret;
970 }
971
972 static int btrfs_delete_delayed_items(struct btrfs_trans_handle *trans,
973 struct btrfs_path *path,
974 struct btrfs_root *root,
975 struct btrfs_delayed_node *node)
976 {
977 struct btrfs_delayed_item *curr, *prev;
978 int ret = 0;
979
980 do_again:
981 mutex_lock(&node->mutex);
982 curr = __btrfs_first_delayed_deletion_item(node);
983 if (!curr)
984 goto delete_fail;
985
986 ret = btrfs_search_slot(trans, root, &curr->key, path, -1, 1);
987 if (ret < 0)
988 goto delete_fail;
989 else if (ret > 0) {
990 /*
991 * can't find the item which the node points to, so this node
992 * is invalid, just drop it.
993 */
994 prev = curr;
995 curr = __btrfs_next_delayed_item(prev);
996 btrfs_release_delayed_item(prev);
997 ret = 0;
998 btrfs_release_path(path);
999 if (curr) {
1000 mutex_unlock(&node->mutex);
1001 goto do_again;
1002 } else
1003 goto delete_fail;
1004 }
1005
1006 btrfs_batch_delete_items(trans, root, path, curr);
1007 btrfs_release_path(path);
1008 mutex_unlock(&node->mutex);
1009 goto do_again;
1010
1011 delete_fail:
1012 btrfs_release_path(path);
1013 mutex_unlock(&node->mutex);
1014 return ret;
1015 }
1016
1017 static void btrfs_release_delayed_inode(struct btrfs_delayed_node *delayed_node)
1018 {
1019 struct btrfs_delayed_root *delayed_root;
1020
1021 if (delayed_node && delayed_node->inode_dirty) {
1022 BUG_ON(!delayed_node->root);
1023 delayed_node->inode_dirty = 0;
1024 delayed_node->count--;
1025
1026 delayed_root = delayed_node->root->fs_info->delayed_root;
1027 finish_one_item(delayed_root);
1028 }
1029 }
1030
1031 static int __btrfs_update_delayed_inode(struct btrfs_trans_handle *trans,
1032 struct btrfs_root *root,
1033 struct btrfs_path *path,
1034 struct btrfs_delayed_node *node)
1035 {
1036 struct btrfs_key key;
1037 struct btrfs_inode_item *inode_item;
1038 struct extent_buffer *leaf;
1039 int ret;
1040
1041 key.objectid = node->inode_id;
1042 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
1043 key.offset = 0;
1044
1045 ret = btrfs_lookup_inode(trans, root, path, &key, 1);
1046 if (ret > 0) {
1047 btrfs_release_path(path);
1048 return -ENOENT;
1049 } else if (ret < 0) {
1050 return ret;
1051 }
1052
1053 btrfs_unlock_up_safe(path, 1);
1054 leaf = path->nodes[0];
1055 inode_item = btrfs_item_ptr(leaf, path->slots[0],
1056 struct btrfs_inode_item);
1057 write_extent_buffer(leaf, &node->inode_item, (unsigned long)inode_item,
1058 sizeof(struct btrfs_inode_item));
1059 btrfs_mark_buffer_dirty(leaf);
1060 btrfs_release_path(path);
1061
1062 btrfs_delayed_inode_release_metadata(root, node);
1063 btrfs_release_delayed_inode(node);
1064
1065 return 0;
1066 }
1067
1068 static inline int btrfs_update_delayed_inode(struct btrfs_trans_handle *trans,
1069 struct btrfs_root *root,
1070 struct btrfs_path *path,
1071 struct btrfs_delayed_node *node)
1072 {
1073 int ret;
1074
1075 mutex_lock(&node->mutex);
1076 if (!node->inode_dirty) {
1077 mutex_unlock(&node->mutex);
1078 return 0;
1079 }
1080
1081 ret = __btrfs_update_delayed_inode(trans, root, path, node);
1082 mutex_unlock(&node->mutex);
1083 return ret;
1084 }
1085
1086 static inline int
1087 __btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
1088 struct btrfs_path *path,
1089 struct btrfs_delayed_node *node)
1090 {
1091 int ret;
1092
1093 ret = btrfs_insert_delayed_items(trans, path, node->root, node);
1094 if (ret)
1095 return ret;
1096
1097 ret = btrfs_delete_delayed_items(trans, path, node->root, node);
1098 if (ret)
1099 return ret;
1100
1101 ret = btrfs_update_delayed_inode(trans, node->root, path, node);
1102 return ret;
1103 }
1104
1105 /*
1106 * Called when committing the transaction.
1107 * Returns 0 on success.
1108 * Returns < 0 on error and returns with an aborted transaction with any
1109 * outstanding delayed items cleaned up.
1110 */
1111 static int __btrfs_run_delayed_items(struct btrfs_trans_handle *trans,
1112 struct btrfs_root *root, int nr)
1113 {
1114 struct btrfs_delayed_root *delayed_root;
1115 struct btrfs_delayed_node *curr_node, *prev_node;
1116 struct btrfs_path *path;
1117 struct btrfs_block_rsv *block_rsv;
1118 int ret = 0;
1119 bool count = (nr > 0);
1120
1121 if (trans->aborted)
1122 return -EIO;
1123
1124 path = btrfs_alloc_path();
1125 if (!path)
1126 return -ENOMEM;
1127 path->leave_spinning = 1;
1128
1129 block_rsv = trans->block_rsv;
1130 trans->block_rsv = &root->fs_info->delayed_block_rsv;
1131
1132 delayed_root = btrfs_get_delayed_root(root);
1133
1134 curr_node = btrfs_first_delayed_node(delayed_root);
1135 while (curr_node && (!count || (count && nr--))) {
1136 ret = __btrfs_commit_inode_delayed_items(trans, path,
1137 curr_node);
1138 if (ret) {
1139 btrfs_release_delayed_node(curr_node);
1140 curr_node = NULL;
1141 btrfs_abort_transaction(trans, root, ret);
1142 break;
1143 }
1144
1145 prev_node = curr_node;
1146 curr_node = btrfs_next_delayed_node(curr_node);
1147 btrfs_release_delayed_node(prev_node);
1148 }
1149
1150 if (curr_node)
1151 btrfs_release_delayed_node(curr_node);
1152 btrfs_free_path(path);
1153 trans->block_rsv = block_rsv;
1154
1155 return ret;
1156 }
1157
1158 int btrfs_run_delayed_items(struct btrfs_trans_handle *trans,
1159 struct btrfs_root *root)
1160 {
1161 return __btrfs_run_delayed_items(trans, root, -1);
1162 }
1163
1164 int btrfs_run_delayed_items_nr(struct btrfs_trans_handle *trans,
1165 struct btrfs_root *root, int nr)
1166 {
1167 return __btrfs_run_delayed_items(trans, root, nr);
1168 }
1169
1170 int btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
1171 struct inode *inode)
1172 {
1173 struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1174 struct btrfs_path *path;
1175 struct btrfs_block_rsv *block_rsv;
1176 int ret;
1177
1178 if (!delayed_node)
1179 return 0;
1180
1181 mutex_lock(&delayed_node->mutex);
1182 if (!delayed_node->count) {
1183 mutex_unlock(&delayed_node->mutex);
1184 btrfs_release_delayed_node(delayed_node);
1185 return 0;
1186 }
1187 mutex_unlock(&delayed_node->mutex);
1188
1189 path = btrfs_alloc_path();
1190 if (!path)
1191 return -ENOMEM;
1192 path->leave_spinning = 1;
1193
1194 block_rsv = trans->block_rsv;
1195 trans->block_rsv = &delayed_node->root->fs_info->delayed_block_rsv;
1196
1197 ret = __btrfs_commit_inode_delayed_items(trans, path, delayed_node);
1198
1199 btrfs_release_delayed_node(delayed_node);
1200 btrfs_free_path(path);
1201 trans->block_rsv = block_rsv;
1202
1203 return ret;
1204 }
1205
1206 int btrfs_commit_inode_delayed_inode(struct inode *inode)
1207 {
1208 struct btrfs_trans_handle *trans;
1209 struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1210 struct btrfs_path *path;
1211 struct btrfs_block_rsv *block_rsv;
1212 int ret;
1213
1214 if (!delayed_node)
1215 return 0;
1216
1217 mutex_lock(&delayed_node->mutex);
1218 if (!delayed_node->inode_dirty) {
1219 mutex_unlock(&delayed_node->mutex);
1220 btrfs_release_delayed_node(delayed_node);
1221 return 0;
1222 }
1223 mutex_unlock(&delayed_node->mutex);
1224
1225 trans = btrfs_join_transaction(delayed_node->root);
1226 if (IS_ERR(trans)) {
1227 ret = PTR_ERR(trans);
1228 goto out;
1229 }
1230
1231 path = btrfs_alloc_path();
1232 if (!path) {
1233 ret = -ENOMEM;
1234 goto trans_out;
1235 }
1236 path->leave_spinning = 1;
1237
1238 block_rsv = trans->block_rsv;
1239 trans->block_rsv = &delayed_node->root->fs_info->delayed_block_rsv;
1240
1241 mutex_lock(&delayed_node->mutex);
1242 if (delayed_node->inode_dirty)
1243 ret = __btrfs_update_delayed_inode(trans, delayed_node->root,
1244 path, delayed_node);
1245 else
1246 ret = 0;
1247 mutex_unlock(&delayed_node->mutex);
1248
1249 btrfs_free_path(path);
1250 trans->block_rsv = block_rsv;
1251 trans_out:
1252 btrfs_end_transaction(trans, delayed_node->root);
1253 btrfs_btree_balance_dirty(delayed_node->root);
1254 out:
1255 btrfs_release_delayed_node(delayed_node);
1256
1257 return ret;
1258 }
1259
1260 void btrfs_remove_delayed_node(struct inode *inode)
1261 {
1262 struct btrfs_delayed_node *delayed_node;
1263
1264 delayed_node = ACCESS_ONCE(BTRFS_I(inode)->delayed_node);
1265 if (!delayed_node)
1266 return;
1267
1268 BTRFS_I(inode)->delayed_node = NULL;
1269 btrfs_release_delayed_node(delayed_node);
1270 }
1271
1272 struct btrfs_async_delayed_work {
1273 struct btrfs_delayed_root *delayed_root;
1274 int nr;
1275 struct btrfs_work work;
1276 };
1277
1278 static void btrfs_async_run_delayed_root(struct btrfs_work *work)
1279 {
1280 struct btrfs_async_delayed_work *async_work;
1281 struct btrfs_delayed_root *delayed_root;
1282 struct btrfs_trans_handle *trans;
1283 struct btrfs_path *path;
1284 struct btrfs_delayed_node *delayed_node = NULL;
1285 struct btrfs_root *root;
1286 struct btrfs_block_rsv *block_rsv;
1287 int total_done = 0;
1288
1289 async_work = container_of(work, struct btrfs_async_delayed_work, work);
1290 delayed_root = async_work->delayed_root;
1291
1292 path = btrfs_alloc_path();
1293 if (!path)
1294 goto out;
1295
1296 again:
1297 if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND / 2)
1298 goto free_path;
1299
1300 delayed_node = btrfs_first_prepared_delayed_node(delayed_root);
1301 if (!delayed_node)
1302 goto free_path;
1303
1304 path->leave_spinning = 1;
1305 root = delayed_node->root;
1306
1307 trans = btrfs_join_transaction(root);
1308 if (IS_ERR(trans))
1309 goto release_path;
1310
1311 block_rsv = trans->block_rsv;
1312 trans->block_rsv = &root->fs_info->delayed_block_rsv;
1313
1314 __btrfs_commit_inode_delayed_items(trans, path, delayed_node);
1315 /*
1316 * Maybe new delayed items have been inserted, so we need requeue
1317 * the work. Besides that, we must dequeue the empty delayed nodes
1318 * to avoid the race between delayed items balance and the worker.
1319 * The race like this:
1320 * Task1 Worker thread
1321 * count == 0, needn't requeue
1322 * also needn't insert the
1323 * delayed node into prepare
1324 * list again.
1325 * add lots of delayed items
1326 * queue the delayed node
1327 * already in the list,
1328 * and not in the prepare
1329 * list, it means the delayed
1330 * node is being dealt with
1331 * by the worker.
1332 * do delayed items balance
1333 * the delayed node is being
1334 * dealt with by the worker
1335 * now, just wait.
1336 * the worker goto idle.
1337 * Task1 will sleep until the transaction is commited.
1338 */
1339 mutex_lock(&delayed_node->mutex);
1340 btrfs_dequeue_delayed_node(root->fs_info->delayed_root, delayed_node);
1341 mutex_unlock(&delayed_node->mutex);
1342
1343 trans->block_rsv = block_rsv;
1344 btrfs_end_transaction_dmeta(trans, root);
1345 btrfs_btree_balance_dirty_nodelay(root);
1346
1347 release_path:
1348 btrfs_release_path(path);
1349 total_done++;
1350
1351 btrfs_release_prepared_delayed_node(delayed_node);
1352 if (async_work->nr == 0 || total_done < async_work->nr)
1353 goto again;
1354
1355 free_path:
1356 btrfs_free_path(path);
1357 out:
1358 wake_up(&delayed_root->wait);
1359 kfree(async_work);
1360 }
1361
1362
1363 static int btrfs_wq_run_delayed_node(struct btrfs_delayed_root *delayed_root,
1364 struct btrfs_root *root, int nr)
1365 {
1366 struct btrfs_async_delayed_work *async_work;
1367
1368 if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND)
1369 return 0;
1370
1371 async_work = kmalloc(sizeof(*async_work), GFP_NOFS);
1372 if (!async_work)
1373 return -ENOMEM;
1374
1375 async_work->delayed_root = delayed_root;
1376 async_work->work.func = btrfs_async_run_delayed_root;
1377 async_work->work.flags = 0;
1378 async_work->nr = nr;
1379
1380 btrfs_queue_worker(&root->fs_info->delayed_workers, &async_work->work);
1381 return 0;
1382 }
1383
1384 void btrfs_assert_delayed_root_empty(struct btrfs_root *root)
1385 {
1386 struct btrfs_delayed_root *delayed_root;
1387 delayed_root = btrfs_get_delayed_root(root);
1388 WARN_ON(btrfs_first_delayed_node(delayed_root));
1389 }
1390
1391 static int refs_newer(struct btrfs_delayed_root *delayed_root,
1392 int seq, int count)
1393 {
1394 int val = atomic_read(&delayed_root->items_seq);
1395
1396 if (val < seq || val >= seq + count)
1397 return 1;
1398 return 0;
1399 }
1400
1401 void btrfs_balance_delayed_items(struct btrfs_root *root)
1402 {
1403 struct btrfs_delayed_root *delayed_root;
1404 int seq;
1405
1406 delayed_root = btrfs_get_delayed_root(root);
1407
1408 if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND)
1409 return;
1410
1411 seq = atomic_read(&delayed_root->items_seq);
1412
1413 if (atomic_read(&delayed_root->items) >= BTRFS_DELAYED_WRITEBACK) {
1414 int ret;
1415 DEFINE_WAIT(__wait);
1416
1417 ret = btrfs_wq_run_delayed_node(delayed_root, root, 0);
1418 if (ret)
1419 return;
1420
1421 while (1) {
1422 prepare_to_wait(&delayed_root->wait, &__wait,
1423 TASK_INTERRUPTIBLE);
1424
1425 if (refs_newer(delayed_root, seq,
1426 BTRFS_DELAYED_BATCH) ||
1427 atomic_read(&delayed_root->items) <
1428 BTRFS_DELAYED_BACKGROUND) {
1429 break;
1430 }
1431 if (!signal_pending(current))
1432 schedule();
1433 else
1434 break;
1435 }
1436 finish_wait(&delayed_root->wait, &__wait);
1437 }
1438
1439 btrfs_wq_run_delayed_node(delayed_root, root, BTRFS_DELAYED_BATCH);
1440 }
1441
1442 /* Will return 0 or -ENOMEM */
1443 int btrfs_insert_delayed_dir_index(struct btrfs_trans_handle *trans,
1444 struct btrfs_root *root, const char *name,
1445 int name_len, struct inode *dir,
1446 struct btrfs_disk_key *disk_key, u8 type,
1447 u64 index)
1448 {
1449 struct btrfs_delayed_node *delayed_node;
1450 struct btrfs_delayed_item *delayed_item;
1451 struct btrfs_dir_item *dir_item;
1452 int ret;
1453
1454 delayed_node = btrfs_get_or_create_delayed_node(dir);
1455 if (IS_ERR(delayed_node))
1456 return PTR_ERR(delayed_node);
1457
1458 delayed_item = btrfs_alloc_delayed_item(sizeof(*dir_item) + name_len);
1459 if (!delayed_item) {
1460 ret = -ENOMEM;
1461 goto release_node;
1462 }
1463
1464 delayed_item->key.objectid = btrfs_ino(dir);
1465 btrfs_set_key_type(&delayed_item->key, BTRFS_DIR_INDEX_KEY);
1466 delayed_item->key.offset = index;
1467
1468 dir_item = (struct btrfs_dir_item *)delayed_item->data;
1469 dir_item->location = *disk_key;
1470 dir_item->transid = cpu_to_le64(trans->transid);
1471 dir_item->data_len = 0;
1472 dir_item->name_len = cpu_to_le16(name_len);
1473 dir_item->type = type;
1474 memcpy((char *)(dir_item + 1), name, name_len);
1475
1476 ret = btrfs_delayed_item_reserve_metadata(trans, root, delayed_item);
1477 /*
1478 * we have reserved enough space when we start a new transaction,
1479 * so reserving metadata failure is impossible
1480 */
1481 BUG_ON(ret);
1482
1483
1484 mutex_lock(&delayed_node->mutex);
1485 ret = __btrfs_add_delayed_insertion_item(delayed_node, delayed_item);
1486 if (unlikely(ret)) {
1487 printk(KERN_ERR "err add delayed dir index item(name: %s) into "
1488 "the insertion tree of the delayed node"
1489 "(root id: %llu, inode id: %llu, errno: %d)\n",
1490 name,
1491 (unsigned long long)delayed_node->root->objectid,
1492 (unsigned long long)delayed_node->inode_id,
1493 ret);
1494 BUG();
1495 }
1496 mutex_unlock(&delayed_node->mutex);
1497
1498 release_node:
1499 btrfs_release_delayed_node(delayed_node);
1500 return ret;
1501 }
1502
1503 static int btrfs_delete_delayed_insertion_item(struct btrfs_root *root,
1504 struct btrfs_delayed_node *node,
1505 struct btrfs_key *key)
1506 {
1507 struct btrfs_delayed_item *item;
1508
1509 mutex_lock(&node->mutex);
1510 item = __btrfs_lookup_delayed_insertion_item(node, key);
1511 if (!item) {
1512 mutex_unlock(&node->mutex);
1513 return 1;
1514 }
1515
1516 btrfs_delayed_item_release_metadata(root, item);
1517 btrfs_release_delayed_item(item);
1518 mutex_unlock(&node->mutex);
1519 return 0;
1520 }
1521
1522 int btrfs_delete_delayed_dir_index(struct btrfs_trans_handle *trans,
1523 struct btrfs_root *root, struct inode *dir,
1524 u64 index)
1525 {
1526 struct btrfs_delayed_node *node;
1527 struct btrfs_delayed_item *item;
1528 struct btrfs_key item_key;
1529 int ret;
1530
1531 node = btrfs_get_or_create_delayed_node(dir);
1532 if (IS_ERR(node))
1533 return PTR_ERR(node);
1534
1535 item_key.objectid = btrfs_ino(dir);
1536 btrfs_set_key_type(&item_key, BTRFS_DIR_INDEX_KEY);
1537 item_key.offset = index;
1538
1539 ret = btrfs_delete_delayed_insertion_item(root, node, &item_key);
1540 if (!ret)
1541 goto end;
1542
1543 item = btrfs_alloc_delayed_item(0);
1544 if (!item) {
1545 ret = -ENOMEM;
1546 goto end;
1547 }
1548
1549 item->key = item_key;
1550
1551 ret = btrfs_delayed_item_reserve_metadata(trans, root, item);
1552 /*
1553 * we have reserved enough space when we start a new transaction,
1554 * so reserving metadata failure is impossible.
1555 */
1556 BUG_ON(ret);
1557
1558 mutex_lock(&node->mutex);
1559 ret = __btrfs_add_delayed_deletion_item(node, item);
1560 if (unlikely(ret)) {
1561 printk(KERN_ERR "err add delayed dir index item(index: %llu) "
1562 "into the deletion tree of the delayed node"
1563 "(root id: %llu, inode id: %llu, errno: %d)\n",
1564 (unsigned long long)index,
1565 (unsigned long long)node->root->objectid,
1566 (unsigned long long)node->inode_id,
1567 ret);
1568 BUG();
1569 }
1570 mutex_unlock(&node->mutex);
1571 end:
1572 btrfs_release_delayed_node(node);
1573 return ret;
1574 }
1575
1576 int btrfs_inode_delayed_dir_index_count(struct inode *inode)
1577 {
1578 struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1579
1580 if (!delayed_node)
1581 return -ENOENT;
1582
1583 /*
1584 * Since we have held i_mutex of this directory, it is impossible that
1585 * a new directory index is added into the delayed node and index_cnt
1586 * is updated now. So we needn't lock the delayed node.
1587 */
1588 if (!delayed_node->index_cnt) {
1589 btrfs_release_delayed_node(delayed_node);
1590 return -EINVAL;
1591 }
1592
1593 BTRFS_I(inode)->index_cnt = delayed_node->index_cnt;
1594 btrfs_release_delayed_node(delayed_node);
1595 return 0;
1596 }
1597
1598 void btrfs_get_delayed_items(struct inode *inode, struct list_head *ins_list,
1599 struct list_head *del_list)
1600 {
1601 struct btrfs_delayed_node *delayed_node;
1602 struct btrfs_delayed_item *item;
1603
1604 delayed_node = btrfs_get_delayed_node(inode);
1605 if (!delayed_node)
1606 return;
1607
1608 mutex_lock(&delayed_node->mutex);
1609 item = __btrfs_first_delayed_insertion_item(delayed_node);
1610 while (item) {
1611 atomic_inc(&item->refs);
1612 list_add_tail(&item->readdir_list, ins_list);
1613 item = __btrfs_next_delayed_item(item);
1614 }
1615
1616 item = __btrfs_first_delayed_deletion_item(delayed_node);
1617 while (item) {
1618 atomic_inc(&item->refs);
1619 list_add_tail(&item->readdir_list, del_list);
1620 item = __btrfs_next_delayed_item(item);
1621 }
1622 mutex_unlock(&delayed_node->mutex);
1623 /*
1624 * This delayed node is still cached in the btrfs inode, so refs
1625 * must be > 1 now, and we needn't check it is going to be freed
1626 * or not.
1627 *
1628 * Besides that, this function is used to read dir, we do not
1629 * insert/delete delayed items in this period. So we also needn't
1630 * requeue or dequeue this delayed node.
1631 */
1632 atomic_dec(&delayed_node->refs);
1633 }
1634
1635 void btrfs_put_delayed_items(struct list_head *ins_list,
1636 struct list_head *del_list)
1637 {
1638 struct btrfs_delayed_item *curr, *next;
1639
1640 list_for_each_entry_safe(curr, next, ins_list, readdir_list) {
1641 list_del(&curr->readdir_list);
1642 if (atomic_dec_and_test(&curr->refs))
1643 kfree(curr);
1644 }
1645
1646 list_for_each_entry_safe(curr, next, del_list, readdir_list) {
1647 list_del(&curr->readdir_list);
1648 if (atomic_dec_and_test(&curr->refs))
1649 kfree(curr);
1650 }
1651 }
1652
1653 int btrfs_should_delete_dir_index(struct list_head *del_list,
1654 u64 index)
1655 {
1656 struct btrfs_delayed_item *curr, *next;
1657 int ret;
1658
1659 if (list_empty(del_list))
1660 return 0;
1661
1662 list_for_each_entry_safe(curr, next, del_list, readdir_list) {
1663 if (curr->key.offset > index)
1664 break;
1665
1666 list_del(&curr->readdir_list);
1667 ret = (curr->key.offset == index);
1668
1669 if (atomic_dec_and_test(&curr->refs))
1670 kfree(curr);
1671
1672 if (ret)
1673 return 1;
1674 else
1675 continue;
1676 }
1677 return 0;
1678 }
1679
1680 /*
1681 * btrfs_readdir_delayed_dir_index - read dir info stored in the delayed tree
1682 *
1683 */
1684 int btrfs_readdir_delayed_dir_index(struct file *filp, void *dirent,
1685 filldir_t filldir,
1686 struct list_head *ins_list)
1687 {
1688 struct btrfs_dir_item *di;
1689 struct btrfs_delayed_item *curr, *next;
1690 struct btrfs_key location;
1691 char *name;
1692 int name_len;
1693 int over = 0;
1694 unsigned char d_type;
1695
1696 if (list_empty(ins_list))
1697 return 0;
1698
1699 /*
1700 * Changing the data of the delayed item is impossible. So
1701 * we needn't lock them. And we have held i_mutex of the
1702 * directory, nobody can delete any directory indexes now.
1703 */
1704 list_for_each_entry_safe(curr, next, ins_list, readdir_list) {
1705 list_del(&curr->readdir_list);
1706
1707 if (curr->key.offset < filp->f_pos) {
1708 if (atomic_dec_and_test(&curr->refs))
1709 kfree(curr);
1710 continue;
1711 }
1712
1713 filp->f_pos = curr->key.offset;
1714
1715 di = (struct btrfs_dir_item *)curr->data;
1716 name = (char *)(di + 1);
1717 name_len = le16_to_cpu(di->name_len);
1718
1719 d_type = btrfs_filetype_table[di->type];
1720 btrfs_disk_key_to_cpu(&location, &di->location);
1721
1722 over = filldir(dirent, name, name_len, curr->key.offset,
1723 location.objectid, d_type);
1724
1725 if (atomic_dec_and_test(&curr->refs))
1726 kfree(curr);
1727
1728 if (over)
1729 return 1;
1730 }
1731 return 0;
1732 }
1733
1734 BTRFS_SETGET_STACK_FUNCS(stack_inode_generation, struct btrfs_inode_item,
1735 generation, 64);
1736 BTRFS_SETGET_STACK_FUNCS(stack_inode_sequence, struct btrfs_inode_item,
1737 sequence, 64);
1738 BTRFS_SETGET_STACK_FUNCS(stack_inode_transid, struct btrfs_inode_item,
1739 transid, 64);
1740 BTRFS_SETGET_STACK_FUNCS(stack_inode_size, struct btrfs_inode_item, size, 64);
1741 BTRFS_SETGET_STACK_FUNCS(stack_inode_nbytes, struct btrfs_inode_item,
1742 nbytes, 64);
1743 BTRFS_SETGET_STACK_FUNCS(stack_inode_block_group, struct btrfs_inode_item,
1744 block_group, 64);
1745 BTRFS_SETGET_STACK_FUNCS(stack_inode_nlink, struct btrfs_inode_item, nlink, 32);
1746 BTRFS_SETGET_STACK_FUNCS(stack_inode_uid, struct btrfs_inode_item, uid, 32);
1747 BTRFS_SETGET_STACK_FUNCS(stack_inode_gid, struct btrfs_inode_item, gid, 32);
1748 BTRFS_SETGET_STACK_FUNCS(stack_inode_mode, struct btrfs_inode_item, mode, 32);
1749 BTRFS_SETGET_STACK_FUNCS(stack_inode_rdev, struct btrfs_inode_item, rdev, 64);
1750 BTRFS_SETGET_STACK_FUNCS(stack_inode_flags, struct btrfs_inode_item, flags, 64);
1751
1752 BTRFS_SETGET_STACK_FUNCS(stack_timespec_sec, struct btrfs_timespec, sec, 64);
1753 BTRFS_SETGET_STACK_FUNCS(stack_timespec_nsec, struct btrfs_timespec, nsec, 32);
1754
1755 static void fill_stack_inode_item(struct btrfs_trans_handle *trans,
1756 struct btrfs_inode_item *inode_item,
1757 struct inode *inode)
1758 {
1759 btrfs_set_stack_inode_uid(inode_item, i_uid_read(inode));
1760 btrfs_set_stack_inode_gid(inode_item, i_gid_read(inode));
1761 btrfs_set_stack_inode_size(inode_item, BTRFS_I(inode)->disk_i_size);
1762 btrfs_set_stack_inode_mode(inode_item, inode->i_mode);
1763 btrfs_set_stack_inode_nlink(inode_item, inode->i_nlink);
1764 btrfs_set_stack_inode_nbytes(inode_item, inode_get_bytes(inode));
1765 btrfs_set_stack_inode_generation(inode_item,
1766 BTRFS_I(inode)->generation);
1767 btrfs_set_stack_inode_sequence(inode_item, inode->i_version);
1768 btrfs_set_stack_inode_transid(inode_item, trans->transid);
1769 btrfs_set_stack_inode_rdev(inode_item, inode->i_rdev);
1770 btrfs_set_stack_inode_flags(inode_item, BTRFS_I(inode)->flags);
1771 btrfs_set_stack_inode_block_group(inode_item, 0);
1772
1773 btrfs_set_stack_timespec_sec(btrfs_inode_atime(inode_item),
1774 inode->i_atime.tv_sec);
1775 btrfs_set_stack_timespec_nsec(btrfs_inode_atime(inode_item),
1776 inode->i_atime.tv_nsec);
1777
1778 btrfs_set_stack_timespec_sec(btrfs_inode_mtime(inode_item),
1779 inode->i_mtime.tv_sec);
1780 btrfs_set_stack_timespec_nsec(btrfs_inode_mtime(inode_item),
1781 inode->i_mtime.tv_nsec);
1782
1783 btrfs_set_stack_timespec_sec(btrfs_inode_ctime(inode_item),
1784 inode->i_ctime.tv_sec);
1785 btrfs_set_stack_timespec_nsec(btrfs_inode_ctime(inode_item),
1786 inode->i_ctime.tv_nsec);
1787 }
1788
1789 int btrfs_fill_inode(struct inode *inode, u32 *rdev)
1790 {
1791 struct btrfs_delayed_node *delayed_node;
1792 struct btrfs_inode_item *inode_item;
1793 struct btrfs_timespec *tspec;
1794
1795 delayed_node = btrfs_get_delayed_node(inode);
1796 if (!delayed_node)
1797 return -ENOENT;
1798
1799 mutex_lock(&delayed_node->mutex);
1800 if (!delayed_node->inode_dirty) {
1801 mutex_unlock(&delayed_node->mutex);
1802 btrfs_release_delayed_node(delayed_node);
1803 return -ENOENT;
1804 }
1805
1806 inode_item = &delayed_node->inode_item;
1807
1808 i_uid_write(inode, btrfs_stack_inode_uid(inode_item));
1809 i_gid_write(inode, btrfs_stack_inode_gid(inode_item));
1810 btrfs_i_size_write(inode, btrfs_stack_inode_size(inode_item));
1811 inode->i_mode = btrfs_stack_inode_mode(inode_item);
1812 set_nlink(inode, btrfs_stack_inode_nlink(inode_item));
1813 inode_set_bytes(inode, btrfs_stack_inode_nbytes(inode_item));
1814 BTRFS_I(inode)->generation = btrfs_stack_inode_generation(inode_item);
1815 inode->i_version = btrfs_stack_inode_sequence(inode_item);
1816 inode->i_rdev = 0;
1817 *rdev = btrfs_stack_inode_rdev(inode_item);
1818 BTRFS_I(inode)->flags = btrfs_stack_inode_flags(inode_item);
1819
1820 tspec = btrfs_inode_atime(inode_item);
1821 inode->i_atime.tv_sec = btrfs_stack_timespec_sec(tspec);
1822 inode->i_atime.tv_nsec = btrfs_stack_timespec_nsec(tspec);
1823
1824 tspec = btrfs_inode_mtime(inode_item);
1825 inode->i_mtime.tv_sec = btrfs_stack_timespec_sec(tspec);
1826 inode->i_mtime.tv_nsec = btrfs_stack_timespec_nsec(tspec);
1827
1828 tspec = btrfs_inode_ctime(inode_item);
1829 inode->i_ctime.tv_sec = btrfs_stack_timespec_sec(tspec);
1830 inode->i_ctime.tv_nsec = btrfs_stack_timespec_nsec(tspec);
1831
1832 inode->i_generation = BTRFS_I(inode)->generation;
1833 BTRFS_I(inode)->index_cnt = (u64)-1;
1834
1835 mutex_unlock(&delayed_node->mutex);
1836 btrfs_release_delayed_node(delayed_node);
1837 return 0;
1838 }
1839
1840 int btrfs_delayed_update_inode(struct btrfs_trans_handle *trans,
1841 struct btrfs_root *root, struct inode *inode)
1842 {
1843 struct btrfs_delayed_node *delayed_node;
1844 int ret = 0;
1845
1846 delayed_node = btrfs_get_or_create_delayed_node(inode);
1847 if (IS_ERR(delayed_node))
1848 return PTR_ERR(delayed_node);
1849
1850 mutex_lock(&delayed_node->mutex);
1851 if (delayed_node->inode_dirty) {
1852 fill_stack_inode_item(trans, &delayed_node->inode_item, inode);
1853 goto release_node;
1854 }
1855
1856 ret = btrfs_delayed_inode_reserve_metadata(trans, root, inode,
1857 delayed_node);
1858 if (ret)
1859 goto release_node;
1860
1861 fill_stack_inode_item(trans, &delayed_node->inode_item, inode);
1862 delayed_node->inode_dirty = 1;
1863 delayed_node->count++;
1864 atomic_inc(&root->fs_info->delayed_root->items);
1865 release_node:
1866 mutex_unlock(&delayed_node->mutex);
1867 btrfs_release_delayed_node(delayed_node);
1868 return ret;
1869 }
1870
1871 static void __btrfs_kill_delayed_node(struct btrfs_delayed_node *delayed_node)
1872 {
1873 struct btrfs_root *root = delayed_node->root;
1874 struct btrfs_delayed_item *curr_item, *prev_item;
1875
1876 mutex_lock(&delayed_node->mutex);
1877 curr_item = __btrfs_first_delayed_insertion_item(delayed_node);
1878 while (curr_item) {
1879 btrfs_delayed_item_release_metadata(root, curr_item);
1880 prev_item = curr_item;
1881 curr_item = __btrfs_next_delayed_item(prev_item);
1882 btrfs_release_delayed_item(prev_item);
1883 }
1884
1885 curr_item = __btrfs_first_delayed_deletion_item(delayed_node);
1886 while (curr_item) {
1887 btrfs_delayed_item_release_metadata(root, curr_item);
1888 prev_item = curr_item;
1889 curr_item = __btrfs_next_delayed_item(prev_item);
1890 btrfs_release_delayed_item(prev_item);
1891 }
1892
1893 if (delayed_node->inode_dirty) {
1894 btrfs_delayed_inode_release_metadata(root, delayed_node);
1895 btrfs_release_delayed_inode(delayed_node);
1896 }
1897 mutex_unlock(&delayed_node->mutex);
1898 }
1899
1900 void btrfs_kill_delayed_inode_items(struct inode *inode)
1901 {
1902 struct btrfs_delayed_node *delayed_node;
1903
1904 delayed_node = btrfs_get_delayed_node(inode);
1905 if (!delayed_node)
1906 return;
1907
1908 __btrfs_kill_delayed_node(delayed_node);
1909 btrfs_release_delayed_node(delayed_node);
1910 }
1911
1912 void btrfs_kill_all_delayed_nodes(struct btrfs_root *root)
1913 {
1914 u64 inode_id = 0;
1915 struct btrfs_delayed_node *delayed_nodes[8];
1916 int i, n;
1917
1918 while (1) {
1919 spin_lock(&root->inode_lock);
1920 n = radix_tree_gang_lookup(&root->delayed_nodes_tree,
1921 (void **)delayed_nodes, inode_id,
1922 ARRAY_SIZE(delayed_nodes));
1923 if (!n) {
1924 spin_unlock(&root->inode_lock);
1925 break;
1926 }
1927
1928 inode_id = delayed_nodes[n - 1]->inode_id + 1;
1929
1930 for (i = 0; i < n; i++)
1931 atomic_inc(&delayed_nodes[i]->refs);
1932 spin_unlock(&root->inode_lock);
1933
1934 for (i = 0; i < n; i++) {
1935 __btrfs_kill_delayed_node(delayed_nodes[i]);
1936 btrfs_release_delayed_node(delayed_nodes[i]);
1937 }
1938 }
1939 }
1940
1941 void btrfs_destroy_delayed_inodes(struct btrfs_root *root)
1942 {
1943 struct btrfs_delayed_root *delayed_root;
1944 struct btrfs_delayed_node *curr_node, *prev_node;
1945
1946 delayed_root = btrfs_get_delayed_root(root);
1947
1948 curr_node = btrfs_first_delayed_node(delayed_root);
1949 while (curr_node) {
1950 __btrfs_kill_delayed_node(curr_node);
1951
1952 prev_node = curr_node;
1953 curr_node = btrfs_next_delayed_node(curr_node);
1954 btrfs_release_delayed_node(prev_node);
1955 }
1956 }
1957