?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
usb: dwc2: gadget: force gadget initialization in dev mode
[linux-2.6/btrfs-unstable.git] / fs / btrfs / ordered-data.c
blob534544e08f769486a97c3c7f3719bed982500783
1 /*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
19 #include <linux/slab.h>
20 #include <linux/blkdev.h>
21 #include <linux/writeback.h>
22 #include <linux/pagevec.h>
23 #include "ctree.h"
24 #include "transaction.h"
25 #include "btrfs_inode.h"
26 #include "extent_io.h"
27 #include "disk-io.h"
28
29 static struct kmem_cache *btrfs_ordered_extent_cache;
30
31 static u64 entry_end(struct btrfs_ordered_extent *entry)
32 {
33 if (entry->file_offset + entry->len < entry->file_offset)
34 return (u64)-1;
35 return entry->file_offset + entry->len;
36 }
37
38 /* returns NULL if the insertion worked, or it returns the node it did find
39 * in the tree
40 */
41 static struct rb_node *tree_insert(struct rb_root *root, u64 file_offset,
42 struct rb_node *node)
43 {
44 struct rb_node **p = &root->rb_node;
45 struct rb_node *parent = NULL;
46 struct btrfs_ordered_extent *entry;
47
48 while (*p) {
49 parent = *p;
50 entry = rb_entry(parent, struct btrfs_ordered_extent, rb_node);
51
52 if (file_offset < entry->file_offset)
53 p = &(*p)->rb_left;
54 else if (file_offset >= entry_end(entry))
55 p = &(*p)->rb_right;
56 else
57 return parent;
58 }
59
60 rb_link_node(node, parent, p);
61 rb_insert_color(node, root);
62 return NULL;
63 }
64
65 static void ordered_data_tree_panic(struct inode *inode, int errno,
66 u64 offset)
67 {
68 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
69 btrfs_panic(fs_info, errno, "Inconsistency in ordered tree at offset "
70 "%llu", offset);
71 }
72
73 /*
74 * look for a given offset in the tree, and if it can't be found return the
75 * first lesser offset
76 */
77 static struct rb_node *__tree_search(struct rb_root *root, u64 file_offset,
78 struct rb_node **prev_ret)
79 {
80 struct rb_node *n = root->rb_node;
81 struct rb_node *prev = NULL;
82 struct rb_node *test;
83 struct btrfs_ordered_extent *entry;
84 struct btrfs_ordered_extent *prev_entry = NULL;
85
86 while (n) {
87 entry = rb_entry(n, struct btrfs_ordered_extent, rb_node);
88 prev = n;
89 prev_entry = entry;
90
91 if (file_offset < entry->file_offset)
92 n = n->rb_left;
93 else if (file_offset >= entry_end(entry))
94 n = n->rb_right;
95 else
96 return n;
97 }
98 if (!prev_ret)
99 return NULL;
100
101 while (prev && file_offset >= entry_end(prev_entry)) {
102 test = rb_next(prev);
103 if (!test)
104 break;
105 prev_entry = rb_entry(test, struct btrfs_ordered_extent,
106 rb_node);
107 if (file_offset < entry_end(prev_entry))
108 break;
109
110 prev = test;
111 }
112 if (prev)
113 prev_entry = rb_entry(prev, struct btrfs_ordered_extent,
114 rb_node);
115 while (prev && file_offset < entry_end(prev_entry)) {
116 test = rb_prev(prev);
117 if (!test)
118 break;
119 prev_entry = rb_entry(test, struct btrfs_ordered_extent,
120 rb_node);
121 prev = test;
122 }
123 *prev_ret = prev;
124 return NULL;
125 }
126
127 /*
128 * helper to check if a given offset is inside a given entry
129 */
130 static int offset_in_entry(struct btrfs_ordered_extent *entry, u64 file_offset)
131 {
132 if (file_offset < entry->file_offset ||
133 entry->file_offset + entry->len <= file_offset)
134 return 0;
135 return 1;
136 }
137
138 static int range_overlaps(struct btrfs_ordered_extent *entry, u64 file_offset,
139 u64 len)
140 {
141 if (file_offset + len <= entry->file_offset ||
142 entry->file_offset + entry->len <= file_offset)
143 return 0;
144 return 1;
145 }
146
147 /*
148 * look find the first ordered struct that has this offset, otherwise
149 * the first one less than this offset
150 */
151 static inline struct rb_node *tree_search(struct btrfs_ordered_inode_tree *tree,
152 u64 file_offset)
153 {
154 struct rb_root *root = &tree->tree;
155 struct rb_node *prev = NULL;
156 struct rb_node *ret;
157 struct btrfs_ordered_extent *entry;
158
159 if (tree->last) {
160 entry = rb_entry(tree->last, struct btrfs_ordered_extent,
161 rb_node);
162 if (offset_in_entry(entry, file_offset))
163 return tree->last;
164 }
165 ret = __tree_search(root, file_offset, &prev);
166 if (!ret)
167 ret = prev;
168 if (ret)
169 tree->last = ret;
170 return ret;
171 }
172
173 /* allocate and add a new ordered_extent into the per-inode tree.
174 * file_offset is the logical offset in the file
175 *
176 * start is the disk block number of an extent already reserved in the
177 * extent allocation tree
178 *
179 * len is the length of the extent
180 *
181 * The tree is given a single reference on the ordered extent that was
182 * inserted.
183 */
184 static int __btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
185 u64 start, u64 len, u64 disk_len,
186 int type, int dio, int compress_type)
187 {
188 struct btrfs_root *root = BTRFS_I(inode)->root;
189 struct btrfs_ordered_inode_tree *tree;
190 struct rb_node *node;
191 struct btrfs_ordered_extent *entry;
192
193 tree = &BTRFS_I(inode)->ordered_tree;
194 entry = kmem_cache_zalloc(btrfs_ordered_extent_cache, GFP_NOFS);
195 if (!entry)
196 return -ENOMEM;
197
198 entry->file_offset = file_offset;
199 entry->start = start;
200 entry->len = len;
201 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM) &&
202 !(type == BTRFS_ORDERED_NOCOW))
203 entry->csum_bytes_left = disk_len;
204 entry->disk_len = disk_len;
205 entry->bytes_left = len;
206 entry->inode = igrab(inode);
207 entry->compress_type = compress_type;
208 entry->truncated_len = (u64)-1;
209 if (type != BTRFS_ORDERED_IO_DONE && type != BTRFS_ORDERED_COMPLETE)
210 set_bit(type, &entry->flags);
211
212 if (dio)
213 set_bit(BTRFS_ORDERED_DIRECT, &entry->flags);
214
215 /* one ref for the tree */
216 atomic_set(&entry->refs, 1);
217 init_waitqueue_head(&entry->wait);
218 INIT_LIST_HEAD(&entry->list);
219 INIT_LIST_HEAD(&entry->root_extent_list);
220 INIT_LIST_HEAD(&entry->work_list);
221 init_completion(&entry->completion);
222 INIT_LIST_HEAD(&entry->log_list);
223 INIT_LIST_HEAD(&entry->trans_list);
224
225 trace_btrfs_ordered_extent_add(inode, entry);
226
227 spin_lock_irq(&tree->lock);
228 node = tree_insert(&tree->tree, file_offset,
229 &entry->rb_node);
230 if (node)
231 ordered_data_tree_panic(inode, -EEXIST, file_offset);
232 spin_unlock_irq(&tree->lock);
233
234 spin_lock(&root->ordered_extent_lock);
235 list_add_tail(&entry->root_extent_list,
236 &root->ordered_extents);
237 root->nr_ordered_extents++;
238 if (root->nr_ordered_extents == 1) {
239 spin_lock(&root->fs_info->ordered_root_lock);
240 BUG_ON(!list_empty(&root->ordered_root));
241 list_add_tail(&root->ordered_root,
242 &root->fs_info->ordered_roots);
243 spin_unlock(&root->fs_info->ordered_root_lock);
244 }
245 spin_unlock(&root->ordered_extent_lock);
246
247 return 0;
248 }
249
250 int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
251 u64 start, u64 len, u64 disk_len, int type)
252 {
253 return __btrfs_add_ordered_extent(inode, file_offset, start, len,
254 disk_len, type, 0,
255 BTRFS_COMPRESS_NONE);
256 }
257
258 int btrfs_add_ordered_extent_dio(struct inode *inode, u64 file_offset,
259 u64 start, u64 len, u64 disk_len, int type)
260 {
261 return __btrfs_add_ordered_extent(inode, file_offset, start, len,
262 disk_len, type, 1,
263 BTRFS_COMPRESS_NONE);
264 }
265
266 int btrfs_add_ordered_extent_compress(struct inode *inode, u64 file_offset,
267 u64 start, u64 len, u64 disk_len,
268 int type, int compress_type)
269 {
270 return __btrfs_add_ordered_extent(inode, file_offset, start, len,
271 disk_len, type, 0,
272 compress_type);
273 }
274
275 /*
276 * Add a struct btrfs_ordered_sum into the list of checksums to be inserted
277 * when an ordered extent is finished. If the list covers more than one
278 * ordered extent, it is split across multiples.
279 */
280 void btrfs_add_ordered_sum(struct inode *inode,
281 struct btrfs_ordered_extent *entry,
282 struct btrfs_ordered_sum *sum)
283 {
284 struct btrfs_ordered_inode_tree *tree;
285
286 tree = &BTRFS_I(inode)->ordered_tree;
287 spin_lock_irq(&tree->lock);
288 list_add_tail(&sum->list, &entry->list);
289 WARN_ON(entry->csum_bytes_left < sum->len);
290 entry->csum_bytes_left -= sum->len;
291 if (entry->csum_bytes_left == 0)
292 wake_up(&entry->wait);
293 spin_unlock_irq(&tree->lock);
294 }
295
296 /*
297 * this is used to account for finished IO across a given range
298 * of the file. The IO may span ordered extents. If
299 * a given ordered_extent is completely done, 1 is returned, otherwise
300 * 0.
301 *
302 * test_and_set_bit on a flag in the struct btrfs_ordered_extent is used
303 * to make sure this function only returns 1 once for a given ordered extent.
304 *
305 * file_offset is updated to one byte past the range that is recorded as
306 * complete. This allows you to walk forward in the file.
307 */
308 int btrfs_dec_test_first_ordered_pending(struct inode *inode,
309 struct btrfs_ordered_extent **cached,
310 u64 *file_offset, u64 io_size, int uptodate)
311 {
312 struct btrfs_ordered_inode_tree *tree;
313 struct rb_node *node;
314 struct btrfs_ordered_extent *entry = NULL;
315 int ret;
316 unsigned long flags;
317 u64 dec_end;
318 u64 dec_start;
319 u64 to_dec;
320
321 tree = &BTRFS_I(inode)->ordered_tree;
322 spin_lock_irqsave(&tree->lock, flags);
323 node = tree_search(tree, *file_offset);
324 if (!node) {
325 ret = 1;
326 goto out;
327 }
328
329 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
330 if (!offset_in_entry(entry, *file_offset)) {
331 ret = 1;
332 goto out;
333 }
334
335 dec_start = max(*file_offset, entry->file_offset);
336 dec_end = min(*file_offset + io_size, entry->file_offset +
337 entry->len);
338 *file_offset = dec_end;
339 if (dec_start > dec_end) {
340 btrfs_crit(BTRFS_I(inode)->root->fs_info,
341 "bad ordering dec_start %llu end %llu", dec_start, dec_end);
342 }
343 to_dec = dec_end - dec_start;
344 if (to_dec > entry->bytes_left) {
345 btrfs_crit(BTRFS_I(inode)->root->fs_info,
346 "bad ordered accounting left %llu size %llu",
347 entry->bytes_left, to_dec);
348 }
349 entry->bytes_left -= to_dec;
350 if (!uptodate)
351 set_bit(BTRFS_ORDERED_IOERR, &entry->flags);
352
353 if (entry->bytes_left == 0) {
354 ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
355 if (waitqueue_active(&entry->wait))
356 wake_up(&entry->wait);
357 } else {
358 ret = 1;
359 }
360 out:
361 if (!ret && cached && entry) {
362 *cached = entry;
363 atomic_inc(&entry->refs);
364 }
365 spin_unlock_irqrestore(&tree->lock, flags);
366 return ret == 0;
367 }
368
369 /*
370 * this is used to account for finished IO across a given range
371 * of the file. The IO should not span ordered extents. If
372 * a given ordered_extent is completely done, 1 is returned, otherwise
373 * 0.
374 *
375 * test_and_set_bit on a flag in the struct btrfs_ordered_extent is used
376 * to make sure this function only returns 1 once for a given ordered extent.
377 */
378 int btrfs_dec_test_ordered_pending(struct inode *inode,
379 struct btrfs_ordered_extent **cached,
380 u64 file_offset, u64 io_size, int uptodate)
381 {
382 struct btrfs_ordered_inode_tree *tree;
383 struct rb_node *node;
384 struct btrfs_ordered_extent *entry = NULL;
385 unsigned long flags;
386 int ret;
387
388 tree = &BTRFS_I(inode)->ordered_tree;
389 spin_lock_irqsave(&tree->lock, flags);
390 if (cached && *cached) {
391 entry = *cached;
392 goto have_entry;
393 }
394
395 node = tree_search(tree, file_offset);
396 if (!node) {
397 ret = 1;
398 goto out;
399 }
400
401 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
402 have_entry:
403 if (!offset_in_entry(entry, file_offset)) {
404 ret = 1;
405 goto out;
406 }
407
408 if (io_size > entry->bytes_left) {
409 btrfs_crit(BTRFS_I(inode)->root->fs_info,
410 "bad ordered accounting left %llu size %llu",
411 entry->bytes_left, io_size);
412 }
413 entry->bytes_left -= io_size;
414 if (!uptodate)
415 set_bit(BTRFS_ORDERED_IOERR, &entry->flags);
416
417 if (entry->bytes_left == 0) {
418 ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
419 if (waitqueue_active(&entry->wait))
420 wake_up(&entry->wait);
421 } else {
422 ret = 1;
423 }
424 out:
425 if (!ret && cached && entry) {
426 *cached = entry;
427 atomic_inc(&entry->refs);
428 }
429 spin_unlock_irqrestore(&tree->lock, flags);
430 return ret == 0;
431 }
432
433 /* Needs to either be called under a log transaction or the log_mutex */
434 void btrfs_get_logged_extents(struct inode *inode,
435 struct list_head *logged_list,
436 const loff_t start,
437 const loff_t end)
438 {
439 struct btrfs_ordered_inode_tree *tree;
440 struct btrfs_ordered_extent *ordered;
441 struct rb_node *n;
442 struct rb_node *prev;
443
444 tree = &BTRFS_I(inode)->ordered_tree;
445 spin_lock_irq(&tree->lock);
446 n = __tree_search(&tree->tree, end, &prev);
447 if (!n)
448 n = prev;
449 for (; n; n = rb_prev(n)) {
450 ordered = rb_entry(n, struct btrfs_ordered_extent, rb_node);
451 if (ordered->file_offset > end)
452 continue;
453 if (entry_end(ordered) <= start)
454 break;
455 if (!list_empty(&ordered->log_list))
456 continue;
457 if (test_bit(BTRFS_ORDERED_LOGGED, &ordered->flags))
458 continue;
459 list_add(&ordered->log_list, logged_list);
460 atomic_inc(&ordered->refs);
461 }
462 spin_unlock_irq(&tree->lock);
463 }
464
465 void btrfs_put_logged_extents(struct list_head *logged_list)
466 {
467 struct btrfs_ordered_extent *ordered;
468
469 while (!list_empty(logged_list)) {
470 ordered = list_first_entry(logged_list,
471 struct btrfs_ordered_extent,
472 log_list);
473 list_del_init(&ordered->log_list);
474 btrfs_put_ordered_extent(ordered);
475 }
476 }
477
478 void btrfs_submit_logged_extents(struct list_head *logged_list,
479 struct btrfs_root *log)
480 {
481 int index = log->log_transid % 2;
482
483 spin_lock_irq(&log->log_extents_lock[index]);
484 list_splice_tail(logged_list, &log->logged_list[index]);
485 spin_unlock_irq(&log->log_extents_lock[index]);
486 }
487
488 void btrfs_wait_logged_extents(struct btrfs_trans_handle *trans,
489 struct btrfs_root *log, u64 transid)
490 {
491 struct btrfs_ordered_extent *ordered;
492 int index = transid % 2;
493
494 spin_lock_irq(&log->log_extents_lock[index]);
495 while (!list_empty(&log->logged_list[index])) {
496 ordered = list_first_entry(&log->logged_list[index],
497 struct btrfs_ordered_extent,
498 log_list);
499 list_del_init(&ordered->log_list);
500 spin_unlock_irq(&log->log_extents_lock[index]);
501
502 if (!test_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags) &&
503 !test_bit(BTRFS_ORDERED_DIRECT, &ordered->flags)) {
504 struct inode *inode = ordered->inode;
505 u64 start = ordered->file_offset;
506 u64 end = ordered->file_offset + ordered->len - 1;
507
508 WARN_ON(!inode);
509 filemap_fdatawrite_range(inode->i_mapping, start, end);
510 }
511 wait_event(ordered->wait, test_bit(BTRFS_ORDERED_IO_DONE,
512 &ordered->flags));
513
514 if (!test_and_set_bit(BTRFS_ORDERED_LOGGED, &ordered->flags))
515 list_add_tail(&ordered->trans_list, &trans->ordered);
516 spin_lock_irq(&log->log_extents_lock[index]);
517 }
518 spin_unlock_irq(&log->log_extents_lock[index]);
519 }
520
521 void btrfs_free_logged_extents(struct btrfs_root *log, u64 transid)
522 {
523 struct btrfs_ordered_extent *ordered;
524 int index = transid % 2;
525
526 spin_lock_irq(&log->log_extents_lock[index]);
527 while (!list_empty(&log->logged_list[index])) {
528 ordered = list_first_entry(&log->logged_list[index],
529 struct btrfs_ordered_extent,
530 log_list);
531 list_del_init(&ordered->log_list);
532 spin_unlock_irq(&log->log_extents_lock[index]);
533 btrfs_put_ordered_extent(ordered);
534 spin_lock_irq(&log->log_extents_lock[index]);
535 }
536 spin_unlock_irq(&log->log_extents_lock[index]);
537 }
538
539 /*
540 * used to drop a reference on an ordered extent. This will free
541 * the extent if the last reference is dropped
542 */
543 void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
544 {
545 struct list_head *cur;
546 struct btrfs_ordered_sum *sum;
547
548 trace_btrfs_ordered_extent_put(entry->inode, entry);
549
550 if (atomic_dec_and_test(&entry->refs)) {
551 if (entry->inode)
552 btrfs_add_delayed_iput(entry->inode);
553 while (!list_empty(&entry->list)) {
554 cur = entry->list.next;
555 sum = list_entry(cur, struct btrfs_ordered_sum, list);
556 list_del(&sum->list);
557 kfree(sum);
558 }
559 kmem_cache_free(btrfs_ordered_extent_cache, entry);
560 }
561 }
562
563 /*
564 * remove an ordered extent from the tree. No references are dropped
565 * and waiters are woken up.
566 */
567 void btrfs_remove_ordered_extent(struct inode *inode,
568 struct btrfs_ordered_extent *entry)
569 {
570 struct btrfs_ordered_inode_tree *tree;
571 struct btrfs_root *root = BTRFS_I(inode)->root;
572 struct rb_node *node;
573
574 tree = &BTRFS_I(inode)->ordered_tree;
575 spin_lock_irq(&tree->lock);
576 node = &entry->rb_node;
577 rb_erase(node, &tree->tree);
578 if (tree->last == node)
579 tree->last = NULL;
580 set_bit(BTRFS_ORDERED_COMPLETE, &entry->flags);
581 spin_unlock_irq(&tree->lock);
582
583 spin_lock(&root->ordered_extent_lock);
584 list_del_init(&entry->root_extent_list);
585 root->nr_ordered_extents--;
586
587 trace_btrfs_ordered_extent_remove(inode, entry);
588
589 if (!root->nr_ordered_extents) {
590 spin_lock(&root->fs_info->ordered_root_lock);
591 BUG_ON(list_empty(&root->ordered_root));
592 list_del_init(&root->ordered_root);
593 spin_unlock(&root->fs_info->ordered_root_lock);
594 }
595 spin_unlock(&root->ordered_extent_lock);
596 wake_up(&entry->wait);
597 }
598
599 static void btrfs_run_ordered_extent_work(struct btrfs_work *work)
600 {
601 struct btrfs_ordered_extent *ordered;
602
603 ordered = container_of(work, struct btrfs_ordered_extent, flush_work);
604 btrfs_start_ordered_extent(ordered->inode, ordered, 1);
605 complete(&ordered->completion);
606 }
607
608 /*
609 * wait for all the ordered extents in a root. This is done when balancing
610 * space between drives.
611 */
612 int btrfs_wait_ordered_extents(struct btrfs_root *root, int nr)
613 {
614 struct list_head splice, works;
615 struct btrfs_ordered_extent *ordered, *next;
616 int count = 0;
617
618 INIT_LIST_HEAD(&splice);
619 INIT_LIST_HEAD(&works);
620
621 mutex_lock(&root->ordered_extent_mutex);
622 spin_lock(&root->ordered_extent_lock);
623 list_splice_init(&root->ordered_extents, &splice);
624 while (!list_empty(&splice) && nr) {
625 ordered = list_first_entry(&splice, struct btrfs_ordered_extent,
626 root_extent_list);
627 list_move_tail(&ordered->root_extent_list,
628 &root->ordered_extents);
629 atomic_inc(&ordered->refs);
630 spin_unlock(&root->ordered_extent_lock);
631
632 btrfs_init_work(&ordered->flush_work,
633 btrfs_flush_delalloc_helper,
634 btrfs_run_ordered_extent_work, NULL, NULL);
635 list_add_tail(&ordered->work_list, &works);
636 btrfs_queue_work(root->fs_info->flush_workers,
637 &ordered->flush_work);
638
639 cond_resched();
640 spin_lock(&root->ordered_extent_lock);
641 if (nr != -1)
642 nr--;
643 count++;
644 }
645 list_splice_tail(&splice, &root->ordered_extents);
646 spin_unlock(&root->ordered_extent_lock);
647
648 list_for_each_entry_safe(ordered, next, &works, work_list) {
649 list_del_init(&ordered->work_list);
650 wait_for_completion(&ordered->completion);
651 btrfs_put_ordered_extent(ordered);
652 cond_resched();
653 }
654 mutex_unlock(&root->ordered_extent_mutex);
655
656 return count;
657 }
658
659 void btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, int nr)
660 {
661 struct btrfs_root *root;
662 struct list_head splice;
663 int done;
664
665 INIT_LIST_HEAD(&splice);
666
667 mutex_lock(&fs_info->ordered_operations_mutex);
668 spin_lock(&fs_info->ordered_root_lock);
669 list_splice_init(&fs_info->ordered_roots, &splice);
670 while (!list_empty(&splice) && nr) {
671 root = list_first_entry(&splice, struct btrfs_root,
672 ordered_root);
673 root = btrfs_grab_fs_root(root);
674 BUG_ON(!root);
675 list_move_tail(&root->ordered_root,
676 &fs_info->ordered_roots);
677 spin_unlock(&fs_info->ordered_root_lock);
678
679 done = btrfs_wait_ordered_extents(root, nr);
680 btrfs_put_fs_root(root);
681
682 spin_lock(&fs_info->ordered_root_lock);
683 if (nr != -1) {
684 nr -= done;
685 WARN_ON(nr < 0);
686 }
687 }
688 list_splice_tail(&splice, &fs_info->ordered_roots);
689 spin_unlock(&fs_info->ordered_root_lock);
690 mutex_unlock(&fs_info->ordered_operations_mutex);
691 }
692
693 /*
694 * Used to start IO or wait for a given ordered extent to finish.
695 *
696 * If wait is one, this effectively waits on page writeback for all the pages
697 * in the extent, and it waits on the io completion code to insert
698 * metadata into the btree corresponding to the extent
699 */
700 void btrfs_start_ordered_extent(struct inode *inode,
701 struct btrfs_ordered_extent *entry,
702 int wait)
703 {
704 u64 start = entry->file_offset;
705 u64 end = start + entry->len - 1;
706
707 trace_btrfs_ordered_extent_start(inode, entry);
708
709 /*
710 * pages in the range can be dirty, clean or writeback. We
711 * start IO on any dirty ones so the wait doesn't stall waiting
712 * for the flusher thread to find them
713 */
714 if (!test_bit(BTRFS_ORDERED_DIRECT, &entry->flags))
715 filemap_fdatawrite_range(inode->i_mapping, start, end);
716 if (wait) {
717 wait_event(entry->wait, test_bit(BTRFS_ORDERED_COMPLETE,
718 &entry->flags));
719 }
720 }
721
722 /*
723 * Used to wait on ordered extents across a large range of bytes.
724 */
725 int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len)
726 {
727 int ret = 0;
728 u64 end;
729 u64 orig_end;
730 struct btrfs_ordered_extent *ordered;
731
732 if (start + len < start) {
733 orig_end = INT_LIMIT(loff_t);
734 } else {
735 orig_end = start + len - 1;
736 if (orig_end > INT_LIMIT(loff_t))
737 orig_end = INT_LIMIT(loff_t);
738 }
739
740 /* start IO across the range first to instantiate any delalloc
741 * extents
742 */
743 ret = btrfs_fdatawrite_range(inode, start, orig_end);
744 if (ret)
745 return ret;
746
747 ret = filemap_fdatawait_range(inode->i_mapping, start, orig_end);
748 if (ret)
749 return ret;
750
751 end = orig_end;
752 while (1) {
753 ordered = btrfs_lookup_first_ordered_extent(inode, end);
754 if (!ordered)
755 break;
756 if (ordered->file_offset > orig_end) {
757 btrfs_put_ordered_extent(ordered);
758 break;
759 }
760 if (ordered->file_offset + ordered->len <= start) {
761 btrfs_put_ordered_extent(ordered);
762 break;
763 }
764 btrfs_start_ordered_extent(inode, ordered, 1);
765 end = ordered->file_offset;
766 if (test_bit(BTRFS_ORDERED_IOERR, &ordered->flags))
767 ret = -EIO;
768 btrfs_put_ordered_extent(ordered);
769 if (ret || end == 0 || end == start)
770 break;
771 end--;
772 }
773 return ret;
774 }
775
776 /*
777 * find an ordered extent corresponding to file_offset. return NULL if
778 * nothing is found, otherwise take a reference on the extent and return it
779 */
780 struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct inode *inode,
781 u64 file_offset)
782 {
783 struct btrfs_ordered_inode_tree *tree;
784 struct rb_node *node;
785 struct btrfs_ordered_extent *entry = NULL;
786
787 tree = &BTRFS_I(inode)->ordered_tree;
788 spin_lock_irq(&tree->lock);
789 node = tree_search(tree, file_offset);
790 if (!node)
791 goto out;
792
793 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
794 if (!offset_in_entry(entry, file_offset))
795 entry = NULL;
796 if (entry)
797 atomic_inc(&entry->refs);
798 out:
799 spin_unlock_irq(&tree->lock);
800 return entry;
801 }
802
803 /* Since the DIO code tries to lock a wide area we need to look for any ordered
804 * extents that exist in the range, rather than just the start of the range.
805 */
806 struct btrfs_ordered_extent *btrfs_lookup_ordered_range(struct inode *inode,
807 u64 file_offset,
808 u64 len)
809 {
810 struct btrfs_ordered_inode_tree *tree;
811 struct rb_node *node;
812 struct btrfs_ordered_extent *entry = NULL;
813
814 tree = &BTRFS_I(inode)->ordered_tree;
815 spin_lock_irq(&tree->lock);
816 node = tree_search(tree, file_offset);
817 if (!node) {
818 node = tree_search(tree, file_offset + len);
819 if (!node)
820 goto out;
821 }
822
823 while (1) {
824 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
825 if (range_overlaps(entry, file_offset, len))
826 break;
827
828 if (entry->file_offset >= file_offset + len) {
829 entry = NULL;
830 break;
831 }
832 entry = NULL;
833 node = rb_next(node);
834 if (!node)
835 break;
836 }
837 out:
838 if (entry)
839 atomic_inc(&entry->refs);
840 spin_unlock_irq(&tree->lock);
841 return entry;
842 }
843
844 /*
845 * lookup and return any extent before 'file_offset'. NULL is returned
846 * if none is found
847 */
848 struct btrfs_ordered_extent *
849 btrfs_lookup_first_ordered_extent(struct inode *inode, u64 file_offset)
850 {
851 struct btrfs_ordered_inode_tree *tree;
852 struct rb_node *node;
853 struct btrfs_ordered_extent *entry = NULL;
854
855 tree = &BTRFS_I(inode)->ordered_tree;
856 spin_lock_irq(&tree->lock);
857 node = tree_search(tree, file_offset);
858 if (!node)
859 goto out;
860
861 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
862 atomic_inc(&entry->refs);
863 out:
864 spin_unlock_irq(&tree->lock);
865 return entry;
866 }
867
868 /*
869 * After an extent is done, call this to conditionally update the on disk
870 * i_size. i_size is updated to cover any fully written part of the file.
871 */
872 int btrfs_ordered_update_i_size(struct inode *inode, u64 offset,
873 struct btrfs_ordered_extent *ordered)
874 {
875 struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
876 u64 disk_i_size;
877 u64 new_i_size;
878 u64 i_size = i_size_read(inode);
879 struct rb_node *node;
880 struct rb_node *prev = NULL;
881 struct btrfs_ordered_extent *test;
882 int ret = 1;
883
884 spin_lock_irq(&tree->lock);
885 if (ordered) {
886 offset = entry_end(ordered);
887 if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags))
888 offset = min(offset,
889 ordered->file_offset +
890 ordered->truncated_len);
891 } else {
892 offset = ALIGN(offset, BTRFS_I(inode)->root->sectorsize);
893 }
894 disk_i_size = BTRFS_I(inode)->disk_i_size;
895
896 /* truncate file */
897 if (disk_i_size > i_size) {
898 BTRFS_I(inode)->disk_i_size = i_size;
899 ret = 0;
900 goto out;
901 }
902
903 /*
904 * if the disk i_size is already at the inode->i_size, or
905 * this ordered extent is inside the disk i_size, we're done
906 */
907 if (disk_i_size == i_size)
908 goto out;
909
910 /*
911 * We still need to update disk_i_size if outstanding_isize is greater
912 * than disk_i_size.
913 */
914 if (offset <= disk_i_size &&
915 (!ordered || ordered->outstanding_isize <= disk_i_size))
916 goto out;
917
918 /*
919 * walk backward from this ordered extent to disk_i_size.
920 * if we find an ordered extent then we can't update disk i_size
921 * yet
922 */
923 if (ordered) {
924 node = rb_prev(&ordered->rb_node);
925 } else {
926 prev = tree_search(tree, offset);
927 /*
928 * we insert file extents without involving ordered struct,
929 * so there should be no ordered struct cover this offset
930 */
931 if (prev) {
932 test = rb_entry(prev, struct btrfs_ordered_extent,
933 rb_node);
934 BUG_ON(offset_in_entry(test, offset));
935 }
936 node = prev;
937 }
938 for (; node; node = rb_prev(node)) {
939 test = rb_entry(node, struct btrfs_ordered_extent, rb_node);
940
941 /* We treat this entry as if it doesnt exist */
942 if (test_bit(BTRFS_ORDERED_UPDATED_ISIZE, &test->flags))
943 continue;
944 if (test->file_offset + test->len <= disk_i_size)
945 break;
946 if (test->file_offset >= i_size)
947 break;
948 if (entry_end(test) > disk_i_size) {
949 /*
950 * we don't update disk_i_size now, so record this
951 * undealt i_size. Or we will not know the real
952 * i_size.
953 */
954 if (test->outstanding_isize < offset)
955 test->outstanding_isize = offset;
956 if (ordered &&
957 ordered->outstanding_isize >
958 test->outstanding_isize)
959 test->outstanding_isize =
960 ordered->outstanding_isize;
961 goto out;
962 }
963 }
964 new_i_size = min_t(u64, offset, i_size);
965
966 /*
967 * Some ordered extents may completed before the current one, and
968 * we hold the real i_size in ->outstanding_isize.
969 */
970 if (ordered && ordered->outstanding_isize > new_i_size)
971 new_i_size = min_t(u64, ordered->outstanding_isize, i_size);
972 BTRFS_I(inode)->disk_i_size = new_i_size;
973 ret = 0;
974 out:
975 /*
976 * We need to do this because we can't remove ordered extents until
977 * after the i_disk_size has been updated and then the inode has been
978 * updated to reflect the change, so we need to tell anybody who finds
979 * this ordered extent that we've already done all the real work, we
980 * just haven't completed all the other work.
981 */
982 if (ordered)
983 set_bit(BTRFS_ORDERED_UPDATED_ISIZE, &ordered->flags);
984 spin_unlock_irq(&tree->lock);
985 return ret;
986 }
987
988 /*
989 * search the ordered extents for one corresponding to 'offset' and
990 * try to find a checksum. This is used because we allow pages to
991 * be reclaimed before their checksum is actually put into the btree
992 */
993 int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
994 u32 *sum, int len)
995 {
996 struct btrfs_ordered_sum *ordered_sum;
997 struct btrfs_ordered_extent *ordered;
998 struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
999 unsigned long num_sectors;
1000 unsigned long i;
1001 u32 sectorsize = BTRFS_I(inode)->root->sectorsize;
1002 int index = 0;
1003
1004 ordered = btrfs_lookup_ordered_extent(inode, offset);
1005 if (!ordered)
1006 return 0;
1007
1008 spin_lock_irq(&tree->lock);
1009 list_for_each_entry_reverse(ordered_sum, &ordered->list, list) {
1010 if (disk_bytenr >= ordered_sum->bytenr &&
1011 disk_bytenr < ordered_sum->bytenr + ordered_sum->len) {
1012 i = (disk_bytenr - ordered_sum->bytenr) >>
1013 inode->i_sb->s_blocksize_bits;
1014 num_sectors = ordered_sum->len >>
1015 inode->i_sb->s_blocksize_bits;
1016 num_sectors = min_t(int, len - index, num_sectors - i);
1017 memcpy(sum + index, ordered_sum->sums + i,
1018 num_sectors);
1019
1020 index += (int)num_sectors;
1021 if (index == len)
1022 goto out;
1023 disk_bytenr += num_sectors * sectorsize;
1024 }
1025 }
1026 out:
1027 spin_unlock_irq(&tree->lock);
1028 btrfs_put_ordered_extent(ordered);
1029 return index;
1030 }
1031
1032 int __init ordered_data_init(void)
1033 {
1034 btrfs_ordered_extent_cache = kmem_cache_create("btrfs_ordered_extent",
1035 sizeof(struct btrfs_ordered_extent), 0,
1036 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
1037 NULL);
1038 if (!btrfs_ordered_extent_cache)
1039 return -ENOMEM;
1040
1041 return 0;
1042 }
1043
1044 void ordered_data_exit(void)
1045 {
1046 if (btrfs_ordered_extent_cache)
1047 kmem_cache_destroy(btrfs_ordered_extent_cache);
1048 }
(deprecated) Btrfs devel tree