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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6#include <linux/slab.h>
7#include <linux/blkdev.h>
8#include <linux/writeback.h>
9#include <linux/sched/mm.h>
10#include "misc.h"
11#include "ctree.h"
12#include "transaction.h"
13#include "btrfs_inode.h"
14#include "extent_io.h"
15#include "disk-io.h"
16#include "compression.h"
17#include "delalloc-space.h"
18
19static struct kmem_cache *btrfs_ordered_extent_cache;
20
21static u64 entry_end(struct btrfs_ordered_extent *entry)
22{
23 if (entry->file_offset + entry->len < entry->file_offset)
24 return (u64)-1;
25 return entry->file_offset + entry->len;
26}
27
28/* returns NULL if the insertion worked, or it returns the node it did find
29 * in the tree
30 */
31static struct rb_node *tree_insert(struct rb_root *root, u64 file_offset,
32 struct rb_node *node)
33{
34 struct rb_node **p = &root->rb_node;
35 struct rb_node *parent = NULL;
36 struct btrfs_ordered_extent *entry;
37
38 while (*p) {
39 parent = *p;
40 entry = rb_entry(parent, struct btrfs_ordered_extent, rb_node);
41
42 if (file_offset < entry->file_offset)
43 p = &(*p)->rb_left;
44 else if (file_offset >= entry_end(entry))
45 p = &(*p)->rb_right;
46 else
47 return parent;
48 }
49
50 rb_link_node(node, parent, p);
51 rb_insert_color(node, root);
52 return NULL;
53}
54
55static void ordered_data_tree_panic(struct inode *inode, int errno,
56 u64 offset)
57{
58 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
59 btrfs_panic(fs_info, errno,
60 "Inconsistency in ordered tree at offset %llu", offset);
61}
62
63/*
64 * look for a given offset in the tree, and if it can't be found return the
65 * first lesser offset
66 */
67static struct rb_node *__tree_search(struct rb_root *root, u64 file_offset,
68 struct rb_node **prev_ret)
69{
70 struct rb_node *n = root->rb_node;
71 struct rb_node *prev = NULL;
72 struct rb_node *test;
73 struct btrfs_ordered_extent *entry;
74 struct btrfs_ordered_extent *prev_entry = NULL;
75
76 while (n) {
77 entry = rb_entry(n, struct btrfs_ordered_extent, rb_node);
78 prev = n;
79 prev_entry = entry;
80
81 if (file_offset < entry->file_offset)
82 n = n->rb_left;
83 else if (file_offset >= entry_end(entry))
84 n = n->rb_right;
85 else
86 return n;
87 }
88 if (!prev_ret)
89 return NULL;
90
91 while (prev && file_offset >= entry_end(prev_entry)) {
92 test = rb_next(prev);
93 if (!test)
94 break;
95 prev_entry = rb_entry(test, struct btrfs_ordered_extent,
96 rb_node);
97 if (file_offset < entry_end(prev_entry))
98 break;
99
100 prev = test;
101 }
102 if (prev)
103 prev_entry = rb_entry(prev, struct btrfs_ordered_extent,
104 rb_node);
105 while (prev && file_offset < entry_end(prev_entry)) {
106 test = rb_prev(prev);
107 if (!test)
108 break;
109 prev_entry = rb_entry(test, struct btrfs_ordered_extent,
110 rb_node);
111 prev = test;
112 }
113 *prev_ret = prev;
114 return NULL;
115}
116
117/*
118 * helper to check if a given offset is inside a given entry
119 */
120static int offset_in_entry(struct btrfs_ordered_extent *entry, u64 file_offset)
121{
122 if (file_offset < entry->file_offset ||
123 entry->file_offset + entry->len <= file_offset)
124 return 0;
125 return 1;
126}
127
128static int range_overlaps(struct btrfs_ordered_extent *entry, u64 file_offset,
129 u64 len)
130{
131 if (file_offset + len <= entry->file_offset ||
132 entry->file_offset + entry->len <= file_offset)
133 return 0;
134 return 1;
135}
136
137/*
138 * look find the first ordered struct that has this offset, otherwise
139 * the first one less than this offset
140 */
141static inline struct rb_node *tree_search(struct btrfs_ordered_inode_tree *tree,
142 u64 file_offset)
143{
144 struct rb_root *root = &tree->tree;
145 struct rb_node *prev = NULL;
146 struct rb_node *ret;
147 struct btrfs_ordered_extent *entry;
148
149 if (tree->last) {
150 entry = rb_entry(tree->last, struct btrfs_ordered_extent,
151 rb_node);
152 if (offset_in_entry(entry, file_offset))
153 return tree->last;
154 }
155 ret = __tree_search(root, file_offset, &prev);
156 if (!ret)
157 ret = prev;
158 if (ret)
159 tree->last = ret;
160 return ret;
161}
162
163/* allocate and add a new ordered_extent into the per-inode tree.
164 * file_offset is the logical offset in the file
165 *
166 * start is the disk block number of an extent already reserved in the
167 * extent allocation tree
168 *
169 * len is the length of the extent
170 *
171 * The tree is given a single reference on the ordered extent that was
172 * inserted.
173 */
174static int __btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
175 u64 start, u64 len, u64 disk_len,
176 int type, int dio, int compress_type)
177{
178 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
179 struct btrfs_root *root = BTRFS_I(inode)->root;
180 struct btrfs_ordered_inode_tree *tree;
181 struct rb_node *node;
182 struct btrfs_ordered_extent *entry;
183
184 tree = &BTRFS_I(inode)->ordered_tree;
185 entry = kmem_cache_zalloc(btrfs_ordered_extent_cache, GFP_NOFS);
186 if (!entry)
187 return -ENOMEM;
188
189 entry->file_offset = file_offset;
190 entry->start = start;
191 entry->len = len;
192 entry->disk_len = disk_len;
193 entry->bytes_left = len;
194 entry->inode = igrab(inode);
195 entry->compress_type = compress_type;
196 entry->truncated_len = (u64)-1;
197 if (type != BTRFS_ORDERED_IO_DONE && type != BTRFS_ORDERED_COMPLETE)
198 set_bit(type, &entry->flags);
199
200 if (dio) {
201 percpu_counter_add_batch(&fs_info->dio_bytes, len,
202 fs_info->delalloc_batch);
203 set_bit(BTRFS_ORDERED_DIRECT, &entry->flags);
204 }
205
206 /* one ref for the tree */
207 refcount_set(&entry->refs, 1);
208 init_waitqueue_head(&entry->wait);
209 INIT_LIST_HEAD(&entry->list);
210 INIT_LIST_HEAD(&entry->root_extent_list);
211 INIT_LIST_HEAD(&entry->work_list);
212 init_completion(&entry->completion);
213 INIT_LIST_HEAD(&entry->log_list);
214 INIT_LIST_HEAD(&entry->trans_list);
215
216 trace_btrfs_ordered_extent_add(inode, entry);
217
218 spin_lock_irq(&tree->lock);
219 node = tree_insert(&tree->tree, file_offset,
220 &entry->rb_node);
221 if (node)
222 ordered_data_tree_panic(inode, -EEXIST, file_offset);
223 spin_unlock_irq(&tree->lock);
224
225 spin_lock(&root->ordered_extent_lock);
226 list_add_tail(&entry->root_extent_list,
227 &root->ordered_extents);
228 root->nr_ordered_extents++;
229 if (root->nr_ordered_extents == 1) {
230 spin_lock(&fs_info->ordered_root_lock);
231 BUG_ON(!list_empty(&root->ordered_root));
232 list_add_tail(&root->ordered_root, &fs_info->ordered_roots);
233 spin_unlock(&fs_info->ordered_root_lock);
234 }
235 spin_unlock(&root->ordered_extent_lock);
236
237 /*
238 * We don't need the count_max_extents here, we can assume that all of
239 * that work has been done at higher layers, so this is truly the
240 * smallest the extent is going to get.
241 */
242 spin_lock(&BTRFS_I(inode)->lock);
243 btrfs_mod_outstanding_extents(BTRFS_I(inode), 1);
244 spin_unlock(&BTRFS_I(inode)->lock);
245
246 return 0;
247}
248
249int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
250 u64 start, u64 len, u64 disk_len, int type)
251{
252 return __btrfs_add_ordered_extent(inode, file_offset, start, len,
253 disk_len, type, 0,
254 BTRFS_COMPRESS_NONE);
255}
256
257int btrfs_add_ordered_extent_dio(struct inode *inode, u64 file_offset,
258 u64 start, u64 len, u64 disk_len, int type)
259{
260 return __btrfs_add_ordered_extent(inode, file_offset, start, len,
261 disk_len, type, 1,
262 BTRFS_COMPRESS_NONE);
263}
264
265int btrfs_add_ordered_extent_compress(struct inode *inode, u64 file_offset,
266 u64 start, u64 len, u64 disk_len,
267 int type, int compress_type)
268{
269 return __btrfs_add_ordered_extent(inode, file_offset, start, len,
270 disk_len, type, 0,
271 compress_type);
272}
273
274/*
275 * Add a struct btrfs_ordered_sum into the list of checksums to be inserted
276 * when an ordered extent is finished. If the list covers more than one
277 * ordered extent, it is split across multiples.
278 */
279void btrfs_add_ordered_sum(struct btrfs_ordered_extent *entry,
280 struct btrfs_ordered_sum *sum)
281{
282 struct btrfs_ordered_inode_tree *tree;
283
284 tree = &BTRFS_I(entry->inode)->ordered_tree;
285 spin_lock_irq(&tree->lock);
286 list_add_tail(&sum->list, &entry->list);
287 spin_unlock_irq(&tree->lock);
288}
289
290/*
291 * this is used to account for finished IO across a given range
292 * of the file. The IO may span ordered extents. If
293 * a given ordered_extent is completely done, 1 is returned, otherwise
294 * 0.
295 *
296 * test_and_set_bit on a flag in the struct btrfs_ordered_extent is used
297 * to make sure this function only returns 1 once for a given ordered extent.
298 *
299 * file_offset is updated to one byte past the range that is recorded as
300 * complete. This allows you to walk forward in the file.
301 */
302int btrfs_dec_test_first_ordered_pending(struct inode *inode,
303 struct btrfs_ordered_extent **cached,
304 u64 *file_offset, u64 io_size, int uptodate)
305{
306 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
307 struct btrfs_ordered_inode_tree *tree;
308 struct rb_node *node;
309 struct btrfs_ordered_extent *entry = NULL;
310 int ret;
311 unsigned long flags;
312 u64 dec_end;
313 u64 dec_start;
314 u64 to_dec;
315
316 tree = &BTRFS_I(inode)->ordered_tree;
317 spin_lock_irqsave(&tree->lock, flags);
318 node = tree_search(tree, *file_offset);
319 if (!node) {
320 ret = 1;
321 goto out;
322 }
323
324 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
325 if (!offset_in_entry(entry, *file_offset)) {
326 ret = 1;
327 goto out;
328 }
329
330 dec_start = max(*file_offset, entry->file_offset);
331 dec_end = min(*file_offset + io_size, entry->file_offset +
332 entry->len);
333 *file_offset = dec_end;
334 if (dec_start > dec_end) {
335 btrfs_crit(fs_info, "bad ordering dec_start %llu end %llu",
336 dec_start, dec_end);
337 }
338 to_dec = dec_end - dec_start;
339 if (to_dec > entry->bytes_left) {
340 btrfs_crit(fs_info,
341 "bad ordered accounting left %llu size %llu",
342 entry->bytes_left, to_dec);
343 }
344 entry->bytes_left -= to_dec;
345 if (!uptodate)
346 set_bit(BTRFS_ORDERED_IOERR, &entry->flags);
347
348 if (entry->bytes_left == 0) {
349 ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
350 /* test_and_set_bit implies a barrier */
351 cond_wake_up_nomb(&entry->wait);
352 } else {
353 ret = 1;
354 }
355out:
356 if (!ret && cached && entry) {
357 *cached = entry;
358 refcount_inc(&entry->refs);
359 }
360 spin_unlock_irqrestore(&tree->lock, flags);
361 return ret == 0;
362}
363
364/*
365 * this is used to account for finished IO across a given range
366 * of the file. The IO should not span ordered extents. If
367 * a given ordered_extent is completely done, 1 is returned, otherwise
368 * 0.
369 *
370 * test_and_set_bit on a flag in the struct btrfs_ordered_extent is used
371 * to make sure this function only returns 1 once for a given ordered extent.
372 */
373int btrfs_dec_test_ordered_pending(struct inode *inode,
374 struct btrfs_ordered_extent **cached,
375 u64 file_offset, u64 io_size, int uptodate)
376{
377 struct btrfs_ordered_inode_tree *tree;
378 struct rb_node *node;
379 struct btrfs_ordered_extent *entry = NULL;
380 unsigned long flags;
381 int ret;
382
383 tree = &BTRFS_I(inode)->ordered_tree;
384 spin_lock_irqsave(&tree->lock, flags);
385 if (cached && *cached) {
386 entry = *cached;
387 goto have_entry;
388 }
389
390 node = tree_search(tree, file_offset);
391 if (!node) {
392 ret = 1;
393 goto out;
394 }
395
396 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
397have_entry:
398 if (!offset_in_entry(entry, file_offset)) {
399 ret = 1;
400 goto out;
401 }
402
403 if (io_size > entry->bytes_left) {
404 btrfs_crit(BTRFS_I(inode)->root->fs_info,
405 "bad ordered accounting left %llu size %llu",
406 entry->bytes_left, io_size);
407 }
408 entry->bytes_left -= io_size;
409 if (!uptodate)
410 set_bit(BTRFS_ORDERED_IOERR, &entry->flags);
411
412 if (entry->bytes_left == 0) {
413 ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
414 /* test_and_set_bit implies a barrier */
415 cond_wake_up_nomb(&entry->wait);
416 } else {
417 ret = 1;
418 }
419out:
420 if (!ret && cached && entry) {
421 *cached = entry;
422 refcount_inc(&entry->refs);
423 }
424 spin_unlock_irqrestore(&tree->lock, flags);
425 return ret == 0;
426}
427
428/*
429 * used to drop a reference on an ordered extent. This will free
430 * the extent if the last reference is dropped
431 */
432void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
433{
434 struct list_head *cur;
435 struct btrfs_ordered_sum *sum;
436
437 trace_btrfs_ordered_extent_put(entry->inode, entry);
438
439 if (refcount_dec_and_test(&entry->refs)) {
440 ASSERT(list_empty(&entry->log_list));
441 ASSERT(list_empty(&entry->trans_list));
442 ASSERT(list_empty(&entry->root_extent_list));
443 ASSERT(RB_EMPTY_NODE(&entry->rb_node));
444 if (entry->inode)
445 btrfs_add_delayed_iput(entry->inode);
446 while (!list_empty(&entry->list)) {
447 cur = entry->list.next;
448 sum = list_entry(cur, struct btrfs_ordered_sum, list);
449 list_del(&sum->list);
450 kvfree(sum);
451 }
452 kmem_cache_free(btrfs_ordered_extent_cache, entry);
453 }
454}
455
456/*
457 * remove an ordered extent from the tree. No references are dropped
458 * and waiters are woken up.
459 */
460void btrfs_remove_ordered_extent(struct inode *inode,
461 struct btrfs_ordered_extent *entry)
462{
463 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
464 struct btrfs_ordered_inode_tree *tree;
465 struct btrfs_inode *btrfs_inode = BTRFS_I(inode);
466 struct btrfs_root *root = btrfs_inode->root;
467 struct rb_node *node;
468
469 /* This is paired with btrfs_add_ordered_extent. */
470 spin_lock(&btrfs_inode->lock);
471 btrfs_mod_outstanding_extents(btrfs_inode, -1);
472 spin_unlock(&btrfs_inode->lock);
473 if (root != fs_info->tree_root)
474 btrfs_delalloc_release_metadata(btrfs_inode, entry->len, false);
475
476 if (test_bit(BTRFS_ORDERED_DIRECT, &entry->flags))
477 percpu_counter_add_batch(&fs_info->dio_bytes, -entry->len,
478 fs_info->delalloc_batch);
479
480 tree = &btrfs_inode->ordered_tree;
481 spin_lock_irq(&tree->lock);
482 node = &entry->rb_node;
483 rb_erase(node, &tree->tree);
484 RB_CLEAR_NODE(node);
485 if (tree->last == node)
486 tree->last = NULL;
487 set_bit(BTRFS_ORDERED_COMPLETE, &entry->flags);
488 spin_unlock_irq(&tree->lock);
489
490 spin_lock(&root->ordered_extent_lock);
491 list_del_init(&entry->root_extent_list);
492 root->nr_ordered_extents--;
493
494 trace_btrfs_ordered_extent_remove(inode, entry);
495
496 if (!root->nr_ordered_extents) {
497 spin_lock(&fs_info->ordered_root_lock);
498 BUG_ON(list_empty(&root->ordered_root));
499 list_del_init(&root->ordered_root);
500 spin_unlock(&fs_info->ordered_root_lock);
501 }
502 spin_unlock(&root->ordered_extent_lock);
503 wake_up(&entry->wait);
504}
505
506static void btrfs_run_ordered_extent_work(struct btrfs_work *work)
507{
508 struct btrfs_ordered_extent *ordered;
509
510 ordered = container_of(work, struct btrfs_ordered_extent, flush_work);
511 btrfs_start_ordered_extent(ordered->inode, ordered, 1);
512 complete(&ordered->completion);
513}
514
515/*
516 * wait for all the ordered extents in a root. This is done when balancing
517 * space between drives.
518 */
519u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,
520 const u64 range_start, const u64 range_len)
521{
522 struct btrfs_fs_info *fs_info = root->fs_info;
523 LIST_HEAD(splice);
524 LIST_HEAD(skipped);
525 LIST_HEAD(works);
526 struct btrfs_ordered_extent *ordered, *next;
527 u64 count = 0;
528 const u64 range_end = range_start + range_len;
529
530 mutex_lock(&root->ordered_extent_mutex);
531 spin_lock(&root->ordered_extent_lock);
532 list_splice_init(&root->ordered_extents, &splice);
533 while (!list_empty(&splice) && nr) {
534 ordered = list_first_entry(&splice, struct btrfs_ordered_extent,
535 root_extent_list);
536
537 if (range_end <= ordered->start ||
538 ordered->start + ordered->disk_len <= range_start) {
539 list_move_tail(&ordered->root_extent_list, &skipped);
540 cond_resched_lock(&root->ordered_extent_lock);
541 continue;
542 }
543
544 list_move_tail(&ordered->root_extent_list,
545 &root->ordered_extents);
546 refcount_inc(&ordered->refs);
547 spin_unlock(&root->ordered_extent_lock);
548
549 btrfs_init_work(&ordered->flush_work,
550 btrfs_flush_delalloc_helper,
551 btrfs_run_ordered_extent_work, NULL, NULL);
552 list_add_tail(&ordered->work_list, &works);
553 btrfs_queue_work(fs_info->flush_workers, &ordered->flush_work);
554
555 cond_resched();
556 spin_lock(&root->ordered_extent_lock);
557 if (nr != U64_MAX)
558 nr--;
559 count++;
560 }
561 list_splice_tail(&skipped, &root->ordered_extents);
562 list_splice_tail(&splice, &root->ordered_extents);
563 spin_unlock(&root->ordered_extent_lock);
564
565 list_for_each_entry_safe(ordered, next, &works, work_list) {
566 list_del_init(&ordered->work_list);
567 wait_for_completion(&ordered->completion);
568 btrfs_put_ordered_extent(ordered);
569 cond_resched();
570 }
571 mutex_unlock(&root->ordered_extent_mutex);
572
573 return count;
574}
575
576u64 btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,
577 const u64 range_start, const u64 range_len)
578{
579 struct btrfs_root *root;
580 struct list_head splice;
581 u64 total_done = 0;
582 u64 done;
583
584 INIT_LIST_HEAD(&splice);
585
586 mutex_lock(&fs_info->ordered_operations_mutex);
587 spin_lock(&fs_info->ordered_root_lock);
588 list_splice_init(&fs_info->ordered_roots, &splice);
589 while (!list_empty(&splice) && nr) {
590 root = list_first_entry(&splice, struct btrfs_root,
591 ordered_root);
592 root = btrfs_grab_fs_root(root);
593 BUG_ON(!root);
594 list_move_tail(&root->ordered_root,
595 &fs_info->ordered_roots);
596 spin_unlock(&fs_info->ordered_root_lock);
597
598 done = btrfs_wait_ordered_extents(root, nr,
599 range_start, range_len);
600 btrfs_put_fs_root(root);
601 total_done += done;
602
603 spin_lock(&fs_info->ordered_root_lock);
604 if (nr != U64_MAX) {
605 nr -= done;
606 }
607 }
608 list_splice_tail(&splice, &fs_info->ordered_roots);
609 spin_unlock(&fs_info->ordered_root_lock);
610 mutex_unlock(&fs_info->ordered_operations_mutex);
611
612 return total_done;
613}
614
615/*
616 * Used to start IO or wait for a given ordered extent to finish.
617 *
618 * If wait is one, this effectively waits on page writeback for all the pages
619 * in the extent, and it waits on the io completion code to insert
620 * metadata into the btree corresponding to the extent
621 */
622void btrfs_start_ordered_extent(struct inode *inode,
623 struct btrfs_ordered_extent *entry,
624 int wait)
625{
626 u64 start = entry->file_offset;
627 u64 end = start + entry->len - 1;
628
629 trace_btrfs_ordered_extent_start(inode, entry);
630
631 /*
632 * pages in the range can be dirty, clean or writeback. We
633 * start IO on any dirty ones so the wait doesn't stall waiting
634 * for the flusher thread to find them
635 */
636 if (!test_bit(BTRFS_ORDERED_DIRECT, &entry->flags))
637 filemap_fdatawrite_range(inode->i_mapping, start, end);
638 if (wait) {
639 wait_event(entry->wait, test_bit(BTRFS_ORDERED_COMPLETE,
640 &entry->flags));
641 }
642}
643
644/*
645 * Used to wait on ordered extents across a large range of bytes.
646 */
647int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len)
648{
649 int ret = 0;
650 int ret_wb = 0;
651 u64 end;
652 u64 orig_end;
653 struct btrfs_ordered_extent *ordered;
654
655 if (start + len < start) {
656 orig_end = INT_LIMIT(loff_t);
657 } else {
658 orig_end = start + len - 1;
659 if (orig_end > INT_LIMIT(loff_t))
660 orig_end = INT_LIMIT(loff_t);
661 }
662
663 /* start IO across the range first to instantiate any delalloc
664 * extents
665 */
666 ret = btrfs_fdatawrite_range(inode, start, orig_end);
667 if (ret)
668 return ret;
669
670 /*
671 * If we have a writeback error don't return immediately. Wait first
672 * for any ordered extents that haven't completed yet. This is to make
673 * sure no one can dirty the same page ranges and call writepages()
674 * before the ordered extents complete - to avoid failures (-EEXIST)
675 * when adding the new ordered extents to the ordered tree.
676 */
677 ret_wb = filemap_fdatawait_range(inode->i_mapping, start, orig_end);
678
679 end = orig_end;
680 while (1) {
681 ordered = btrfs_lookup_first_ordered_extent(inode, end);
682 if (!ordered)
683 break;
684 if (ordered->file_offset > orig_end) {
685 btrfs_put_ordered_extent(ordered);
686 break;
687 }
688 if (ordered->file_offset + ordered->len <= start) {
689 btrfs_put_ordered_extent(ordered);
690 break;
691 }
692 btrfs_start_ordered_extent(inode, ordered, 1);
693 end = ordered->file_offset;
694 if (test_bit(BTRFS_ORDERED_IOERR, &ordered->flags))
695 ret = -EIO;
696 btrfs_put_ordered_extent(ordered);
697 if (ret || end == 0 || end == start)
698 break;
699 end--;
700 }
701 return ret_wb ? ret_wb : ret;
702}
703
704/*
705 * find an ordered extent corresponding to file_offset. return NULL if
706 * nothing is found, otherwise take a reference on the extent and return it
707 */
708struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct inode *inode,
709 u64 file_offset)
710{
711 struct btrfs_ordered_inode_tree *tree;
712 struct rb_node *node;
713 struct btrfs_ordered_extent *entry = NULL;
714
715 tree = &BTRFS_I(inode)->ordered_tree;
716 spin_lock_irq(&tree->lock);
717 node = tree_search(tree, file_offset);
718 if (!node)
719 goto out;
720
721 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
722 if (!offset_in_entry(entry, file_offset))
723 entry = NULL;
724 if (entry)
725 refcount_inc(&entry->refs);
726out:
727 spin_unlock_irq(&tree->lock);
728 return entry;
729}
730
731/* Since the DIO code tries to lock a wide area we need to look for any ordered
732 * extents that exist in the range, rather than just the start of the range.
733 */
734struct btrfs_ordered_extent *btrfs_lookup_ordered_range(
735 struct btrfs_inode *inode, u64 file_offset, u64 len)
736{
737 struct btrfs_ordered_inode_tree *tree;
738 struct rb_node *node;
739 struct btrfs_ordered_extent *entry = NULL;
740
741 tree = &inode->ordered_tree;
742 spin_lock_irq(&tree->lock);
743 node = tree_search(tree, file_offset);
744 if (!node) {
745 node = tree_search(tree, file_offset + len);
746 if (!node)
747 goto out;
748 }
749
750 while (1) {
751 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
752 if (range_overlaps(entry, file_offset, len))
753 break;
754
755 if (entry->file_offset >= file_offset + len) {
756 entry = NULL;
757 break;
758 }
759 entry = NULL;
760 node = rb_next(node);
761 if (!node)
762 break;
763 }
764out:
765 if (entry)
766 refcount_inc(&entry->refs);
767 spin_unlock_irq(&tree->lock);
768 return entry;
769}
770
771/*
772 * lookup and return any extent before 'file_offset'. NULL is returned
773 * if none is found
774 */
775struct btrfs_ordered_extent *
776btrfs_lookup_first_ordered_extent(struct inode *inode, u64 file_offset)
777{
778 struct btrfs_ordered_inode_tree *tree;
779 struct rb_node *node;
780 struct btrfs_ordered_extent *entry = NULL;
781
782 tree = &BTRFS_I(inode)->ordered_tree;
783 spin_lock_irq(&tree->lock);
784 node = tree_search(tree, file_offset);
785 if (!node)
786 goto out;
787
788 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
789 refcount_inc(&entry->refs);
790out:
791 spin_unlock_irq(&tree->lock);
792 return entry;
793}
794
795/*
796 * After an extent is done, call this to conditionally update the on disk
797 * i_size. i_size is updated to cover any fully written part of the file.
798 */
799int btrfs_ordered_update_i_size(struct inode *inode, u64 offset,
800 struct btrfs_ordered_extent *ordered)
801{
802 struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
803 u64 disk_i_size;
804 u64 new_i_size;
805 u64 i_size = i_size_read(inode);
806 struct rb_node *node;
807 struct rb_node *prev = NULL;
808 struct btrfs_ordered_extent *test;
809 int ret = 1;
810 u64 orig_offset = offset;
811
812 spin_lock_irq(&tree->lock);
813 if (ordered) {
814 offset = entry_end(ordered);
815 if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags))
816 offset = min(offset,
817 ordered->file_offset +
818 ordered->truncated_len);
819 } else {
820 offset = ALIGN(offset, btrfs_inode_sectorsize(inode));
821 }
822 disk_i_size = BTRFS_I(inode)->disk_i_size;
823
824 /*
825 * truncate file.
826 * If ordered is not NULL, then this is called from endio and
827 * disk_i_size will be updated by either truncate itself or any
828 * in-flight IOs which are inside the disk_i_size.
829 *
830 * Because btrfs_setsize() may set i_size with disk_i_size if truncate
831 * fails somehow, we need to make sure we have a precise disk_i_size by
832 * updating it as usual.
833 *
834 */
835 if (!ordered && disk_i_size > i_size) {
836 BTRFS_I(inode)->disk_i_size = orig_offset;
837 ret = 0;
838 goto out;
839 }
840
841 /*
842 * if the disk i_size is already at the inode->i_size, or
843 * this ordered extent is inside the disk i_size, we're done
844 */
845 if (disk_i_size == i_size)
846 goto out;
847
848 /*
849 * We still need to update disk_i_size if outstanding_isize is greater
850 * than disk_i_size.
851 */
852 if (offset <= disk_i_size &&
853 (!ordered || ordered->outstanding_isize <= disk_i_size))
854 goto out;
855
856 /*
857 * walk backward from this ordered extent to disk_i_size.
858 * if we find an ordered extent then we can't update disk i_size
859 * yet
860 */
861 if (ordered) {
862 node = rb_prev(&ordered->rb_node);
863 } else {
864 prev = tree_search(tree, offset);
865 /*
866 * we insert file extents without involving ordered struct,
867 * so there should be no ordered struct cover this offset
868 */
869 if (prev) {
870 test = rb_entry(prev, struct btrfs_ordered_extent,
871 rb_node);
872 BUG_ON(offset_in_entry(test, offset));
873 }
874 node = prev;
875 }
876 for (; node; node = rb_prev(node)) {
877 test = rb_entry(node, struct btrfs_ordered_extent, rb_node);
878
879 /* We treat this entry as if it doesn't exist */
880 if (test_bit(BTRFS_ORDERED_UPDATED_ISIZE, &test->flags))
881 continue;
882
883 if (entry_end(test) <= disk_i_size)
884 break;
885 if (test->file_offset >= i_size)
886 break;
887
888 /*
889 * We don't update disk_i_size now, so record this undealt
890 * i_size. Or we will not know the real i_size.
891 */
892 if (test->outstanding_isize < offset)
893 test->outstanding_isize = offset;
894 if (ordered &&
895 ordered->outstanding_isize > test->outstanding_isize)
896 test->outstanding_isize = ordered->outstanding_isize;
897 goto out;
898 }
899 new_i_size = min_t(u64, offset, i_size);
900
901 /*
902 * Some ordered extents may completed before the current one, and
903 * we hold the real i_size in ->outstanding_isize.
904 */
905 if (ordered && ordered->outstanding_isize > new_i_size)
906 new_i_size = min_t(u64, ordered->outstanding_isize, i_size);
907 BTRFS_I(inode)->disk_i_size = new_i_size;
908 ret = 0;
909out:
910 /*
911 * We need to do this because we can't remove ordered extents until
912 * after the i_disk_size has been updated and then the inode has been
913 * updated to reflect the change, so we need to tell anybody who finds
914 * this ordered extent that we've already done all the real work, we
915 * just haven't completed all the other work.
916 */
917 if (ordered)
918 set_bit(BTRFS_ORDERED_UPDATED_ISIZE, &ordered->flags);
919 spin_unlock_irq(&tree->lock);
920 return ret;
921}
922
923/*
924 * search the ordered extents for one corresponding to 'offset' and
925 * try to find a checksum. This is used because we allow pages to
926 * be reclaimed before their checksum is actually put into the btree
927 */
928int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
929 u8 *sum, int len)
930{
931 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
932 struct btrfs_ordered_sum *ordered_sum;
933 struct btrfs_ordered_extent *ordered;
934 struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
935 unsigned long num_sectors;
936 unsigned long i;
937 u32 sectorsize = btrfs_inode_sectorsize(inode);
938 const u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
939 int index = 0;
940
941 ordered = btrfs_lookup_ordered_extent(inode, offset);
942 if (!ordered)
943 return 0;
944
945 spin_lock_irq(&tree->lock);
946 list_for_each_entry_reverse(ordered_sum, &ordered->list, list) {
947 if (disk_bytenr >= ordered_sum->bytenr &&
948 disk_bytenr < ordered_sum->bytenr + ordered_sum->len) {
949 i = (disk_bytenr - ordered_sum->bytenr) >>
950 inode->i_sb->s_blocksize_bits;
951 num_sectors = ordered_sum->len >>
952 inode->i_sb->s_blocksize_bits;
953 num_sectors = min_t(int, len - index, num_sectors - i);
954 memcpy(sum + index, ordered_sum->sums + i * csum_size,
955 num_sectors * csum_size);
956
957 index += (int)num_sectors * csum_size;
958 if (index == len)
959 goto out;
960 disk_bytenr += num_sectors * sectorsize;
961 }
962 }
963out:
964 spin_unlock_irq(&tree->lock);
965 btrfs_put_ordered_extent(ordered);
966 return index;
967}
968
969/*
970 * btrfs_flush_ordered_range - Lock the passed range and ensures all pending
971 * ordered extents in it are run to completion.
972 *
973 * @tree: IO tree used for locking out other users of the range
974 * @inode: Inode whose ordered tree is to be searched
975 * @start: Beginning of range to flush
976 * @end: Last byte of range to lock
977 * @cached_state: If passed, will return the extent state responsible for the
978 * locked range. It's the caller's responsibility to free the cached state.
979 *
980 * This function always returns with the given range locked, ensuring after it's
981 * called no order extent can be pending.
982 */
983void btrfs_lock_and_flush_ordered_range(struct extent_io_tree *tree,
984 struct btrfs_inode *inode, u64 start,
985 u64 end,
986 struct extent_state **cached_state)
987{
988 struct btrfs_ordered_extent *ordered;
989 struct extent_state *cache = NULL;
990 struct extent_state **cachedp = &cache;
991
992 if (cached_state)
993 cachedp = cached_state;
994
995 while (1) {
996 lock_extent_bits(tree, start, end, cachedp);
997 ordered = btrfs_lookup_ordered_range(inode, start,
998 end - start + 1);
999 if (!ordered) {
1000 /*
1001 * If no external cached_state has been passed then
1002 * decrement the extra ref taken for cachedp since we
1003 * aren't exposing it outside of this function
1004 */
1005 if (!cached_state)
1006 refcount_dec(&cache->refs);
1007 break;
1008 }
1009 unlock_extent_cached(tree, start, end, cachedp);
1010 btrfs_start_ordered_extent(&inode->vfs_inode, ordered, 1);
1011 btrfs_put_ordered_extent(ordered);
1012 }
1013}
1014
1015int __init ordered_data_init(void)
1016{
1017 btrfs_ordered_extent_cache = kmem_cache_create("btrfs_ordered_extent",
1018 sizeof(struct btrfs_ordered_extent), 0,
1019 SLAB_MEM_SPREAD,
1020 NULL);
1021 if (!btrfs_ordered_extent_cache)
1022 return -ENOMEM;
1023
1024 return 0;
1025}
1026
1027void __cold ordered_data_exit(void)
1028{
1029 kmem_cache_destroy(btrfs_ordered_extent_cache);
1030}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6#include <linux/slab.h>
7#include <linux/blkdev.h>
8#include <linux/writeback.h>
9#include <linux/pagevec.h>
10#include "ctree.h"
11#include "transaction.h"
12#include "btrfs_inode.h"
13#include "extent_io.h"
14#include "disk-io.h"
15#include "compression.h"
16
17static struct kmem_cache *btrfs_ordered_extent_cache;
18
19static u64 entry_end(struct btrfs_ordered_extent *entry)
20{
21 if (entry->file_offset + entry->len < entry->file_offset)
22 return (u64)-1;
23 return entry->file_offset + entry->len;
24}
25
26/* returns NULL if the insertion worked, or it returns the node it did find
27 * in the tree
28 */
29static struct rb_node *tree_insert(struct rb_root *root, u64 file_offset,
30 struct rb_node *node)
31{
32 struct rb_node **p = &root->rb_node;
33 struct rb_node *parent = NULL;
34 struct btrfs_ordered_extent *entry;
35
36 while (*p) {
37 parent = *p;
38 entry = rb_entry(parent, struct btrfs_ordered_extent, rb_node);
39
40 if (file_offset < entry->file_offset)
41 p = &(*p)->rb_left;
42 else if (file_offset >= entry_end(entry))
43 p = &(*p)->rb_right;
44 else
45 return parent;
46 }
47
48 rb_link_node(node, parent, p);
49 rb_insert_color(node, root);
50 return NULL;
51}
52
53static void ordered_data_tree_panic(struct inode *inode, int errno,
54 u64 offset)
55{
56 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
57 btrfs_panic(fs_info, errno,
58 "Inconsistency in ordered tree at offset %llu", offset);
59}
60
61/*
62 * look for a given offset in the tree, and if it can't be found return the
63 * first lesser offset
64 */
65static struct rb_node *__tree_search(struct rb_root *root, u64 file_offset,
66 struct rb_node **prev_ret)
67{
68 struct rb_node *n = root->rb_node;
69 struct rb_node *prev = NULL;
70 struct rb_node *test;
71 struct btrfs_ordered_extent *entry;
72 struct btrfs_ordered_extent *prev_entry = NULL;
73
74 while (n) {
75 entry = rb_entry(n, struct btrfs_ordered_extent, rb_node);
76 prev = n;
77 prev_entry = entry;
78
79 if (file_offset < entry->file_offset)
80 n = n->rb_left;
81 else if (file_offset >= entry_end(entry))
82 n = n->rb_right;
83 else
84 return n;
85 }
86 if (!prev_ret)
87 return NULL;
88
89 while (prev && file_offset >= entry_end(prev_entry)) {
90 test = rb_next(prev);
91 if (!test)
92 break;
93 prev_entry = rb_entry(test, struct btrfs_ordered_extent,
94 rb_node);
95 if (file_offset < entry_end(prev_entry))
96 break;
97
98 prev = test;
99 }
100 if (prev)
101 prev_entry = rb_entry(prev, struct btrfs_ordered_extent,
102 rb_node);
103 while (prev && file_offset < entry_end(prev_entry)) {
104 test = rb_prev(prev);
105 if (!test)
106 break;
107 prev_entry = rb_entry(test, struct btrfs_ordered_extent,
108 rb_node);
109 prev = test;
110 }
111 *prev_ret = prev;
112 return NULL;
113}
114
115/*
116 * helper to check if a given offset is inside a given entry
117 */
118static int offset_in_entry(struct btrfs_ordered_extent *entry, u64 file_offset)
119{
120 if (file_offset < entry->file_offset ||
121 entry->file_offset + entry->len <= file_offset)
122 return 0;
123 return 1;
124}
125
126static int range_overlaps(struct btrfs_ordered_extent *entry, u64 file_offset,
127 u64 len)
128{
129 if (file_offset + len <= entry->file_offset ||
130 entry->file_offset + entry->len <= file_offset)
131 return 0;
132 return 1;
133}
134
135/*
136 * look find the first ordered struct that has this offset, otherwise
137 * the first one less than this offset
138 */
139static inline struct rb_node *tree_search(struct btrfs_ordered_inode_tree *tree,
140 u64 file_offset)
141{
142 struct rb_root *root = &tree->tree;
143 struct rb_node *prev = NULL;
144 struct rb_node *ret;
145 struct btrfs_ordered_extent *entry;
146
147 if (tree->last) {
148 entry = rb_entry(tree->last, struct btrfs_ordered_extent,
149 rb_node);
150 if (offset_in_entry(entry, file_offset))
151 return tree->last;
152 }
153 ret = __tree_search(root, file_offset, &prev);
154 if (!ret)
155 ret = prev;
156 if (ret)
157 tree->last = ret;
158 return ret;
159}
160
161/* allocate and add a new ordered_extent into the per-inode tree.
162 * file_offset is the logical offset in the file
163 *
164 * start is the disk block number of an extent already reserved in the
165 * extent allocation tree
166 *
167 * len is the length of the extent
168 *
169 * The tree is given a single reference on the ordered extent that was
170 * inserted.
171 */
172static int __btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
173 u64 start, u64 len, u64 disk_len,
174 int type, int dio, int compress_type)
175{
176 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
177 struct btrfs_root *root = BTRFS_I(inode)->root;
178 struct btrfs_ordered_inode_tree *tree;
179 struct rb_node *node;
180 struct btrfs_ordered_extent *entry;
181
182 tree = &BTRFS_I(inode)->ordered_tree;
183 entry = kmem_cache_zalloc(btrfs_ordered_extent_cache, GFP_NOFS);
184 if (!entry)
185 return -ENOMEM;
186
187 entry->file_offset = file_offset;
188 entry->start = start;
189 entry->len = len;
190 entry->disk_len = disk_len;
191 entry->bytes_left = len;
192 entry->inode = igrab(inode);
193 entry->compress_type = compress_type;
194 entry->truncated_len = (u64)-1;
195 if (type != BTRFS_ORDERED_IO_DONE && type != BTRFS_ORDERED_COMPLETE)
196 set_bit(type, &entry->flags);
197
198 if (dio)
199 set_bit(BTRFS_ORDERED_DIRECT, &entry->flags);
200
201 /* one ref for the tree */
202 refcount_set(&entry->refs, 1);
203 init_waitqueue_head(&entry->wait);
204 INIT_LIST_HEAD(&entry->list);
205 INIT_LIST_HEAD(&entry->root_extent_list);
206 INIT_LIST_HEAD(&entry->work_list);
207 init_completion(&entry->completion);
208 INIT_LIST_HEAD(&entry->log_list);
209 INIT_LIST_HEAD(&entry->trans_list);
210
211 trace_btrfs_ordered_extent_add(inode, entry);
212
213 spin_lock_irq(&tree->lock);
214 node = tree_insert(&tree->tree, file_offset,
215 &entry->rb_node);
216 if (node)
217 ordered_data_tree_panic(inode, -EEXIST, file_offset);
218 spin_unlock_irq(&tree->lock);
219
220 spin_lock(&root->ordered_extent_lock);
221 list_add_tail(&entry->root_extent_list,
222 &root->ordered_extents);
223 root->nr_ordered_extents++;
224 if (root->nr_ordered_extents == 1) {
225 spin_lock(&fs_info->ordered_root_lock);
226 BUG_ON(!list_empty(&root->ordered_root));
227 list_add_tail(&root->ordered_root, &fs_info->ordered_roots);
228 spin_unlock(&fs_info->ordered_root_lock);
229 }
230 spin_unlock(&root->ordered_extent_lock);
231
232 /*
233 * We don't need the count_max_extents here, we can assume that all of
234 * that work has been done at higher layers, so this is truly the
235 * smallest the extent is going to get.
236 */
237 spin_lock(&BTRFS_I(inode)->lock);
238 btrfs_mod_outstanding_extents(BTRFS_I(inode), 1);
239 spin_unlock(&BTRFS_I(inode)->lock);
240
241 return 0;
242}
243
244int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
245 u64 start, u64 len, u64 disk_len, int type)
246{
247 return __btrfs_add_ordered_extent(inode, file_offset, start, len,
248 disk_len, type, 0,
249 BTRFS_COMPRESS_NONE);
250}
251
252int btrfs_add_ordered_extent_dio(struct inode *inode, u64 file_offset,
253 u64 start, u64 len, u64 disk_len, int type)
254{
255 return __btrfs_add_ordered_extent(inode, file_offset, start, len,
256 disk_len, type, 1,
257 BTRFS_COMPRESS_NONE);
258}
259
260int btrfs_add_ordered_extent_compress(struct inode *inode, u64 file_offset,
261 u64 start, u64 len, u64 disk_len,
262 int type, int compress_type)
263{
264 return __btrfs_add_ordered_extent(inode, file_offset, start, len,
265 disk_len, type, 0,
266 compress_type);
267}
268
269/*
270 * Add a struct btrfs_ordered_sum into the list of checksums to be inserted
271 * when an ordered extent is finished. If the list covers more than one
272 * ordered extent, it is split across multiples.
273 */
274void btrfs_add_ordered_sum(struct inode *inode,
275 struct btrfs_ordered_extent *entry,
276 struct btrfs_ordered_sum *sum)
277{
278 struct btrfs_ordered_inode_tree *tree;
279
280 tree = &BTRFS_I(inode)->ordered_tree;
281 spin_lock_irq(&tree->lock);
282 list_add_tail(&sum->list, &entry->list);
283 spin_unlock_irq(&tree->lock);
284}
285
286/*
287 * this is used to account for finished IO across a given range
288 * of the file. The IO may span ordered extents. If
289 * a given ordered_extent is completely done, 1 is returned, otherwise
290 * 0.
291 *
292 * test_and_set_bit on a flag in the struct btrfs_ordered_extent is used
293 * to make sure this function only returns 1 once for a given ordered extent.
294 *
295 * file_offset is updated to one byte past the range that is recorded as
296 * complete. This allows you to walk forward in the file.
297 */
298int btrfs_dec_test_first_ordered_pending(struct inode *inode,
299 struct btrfs_ordered_extent **cached,
300 u64 *file_offset, u64 io_size, int uptodate)
301{
302 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
303 struct btrfs_ordered_inode_tree *tree;
304 struct rb_node *node;
305 struct btrfs_ordered_extent *entry = NULL;
306 int ret;
307 unsigned long flags;
308 u64 dec_end;
309 u64 dec_start;
310 u64 to_dec;
311
312 tree = &BTRFS_I(inode)->ordered_tree;
313 spin_lock_irqsave(&tree->lock, flags);
314 node = tree_search(tree, *file_offset);
315 if (!node) {
316 ret = 1;
317 goto out;
318 }
319
320 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
321 if (!offset_in_entry(entry, *file_offset)) {
322 ret = 1;
323 goto out;
324 }
325
326 dec_start = max(*file_offset, entry->file_offset);
327 dec_end = min(*file_offset + io_size, entry->file_offset +
328 entry->len);
329 *file_offset = dec_end;
330 if (dec_start > dec_end) {
331 btrfs_crit(fs_info, "bad ordering dec_start %llu end %llu",
332 dec_start, dec_end);
333 }
334 to_dec = dec_end - dec_start;
335 if (to_dec > entry->bytes_left) {
336 btrfs_crit(fs_info,
337 "bad ordered accounting left %llu size %llu",
338 entry->bytes_left, to_dec);
339 }
340 entry->bytes_left -= to_dec;
341 if (!uptodate)
342 set_bit(BTRFS_ORDERED_IOERR, &entry->flags);
343
344 if (entry->bytes_left == 0) {
345 ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
346 /*
347 * Implicit memory barrier after test_and_set_bit
348 */
349 if (waitqueue_active(&entry->wait))
350 wake_up(&entry->wait);
351 } else {
352 ret = 1;
353 }
354out:
355 if (!ret && cached && entry) {
356 *cached = entry;
357 refcount_inc(&entry->refs);
358 }
359 spin_unlock_irqrestore(&tree->lock, flags);
360 return ret == 0;
361}
362
363/*
364 * this is used to account for finished IO across a given range
365 * of the file. The IO should not span ordered extents. If
366 * a given ordered_extent is completely done, 1 is returned, otherwise
367 * 0.
368 *
369 * test_and_set_bit on a flag in the struct btrfs_ordered_extent is used
370 * to make sure this function only returns 1 once for a given ordered extent.
371 */
372int btrfs_dec_test_ordered_pending(struct inode *inode,
373 struct btrfs_ordered_extent **cached,
374 u64 file_offset, u64 io_size, int uptodate)
375{
376 struct btrfs_ordered_inode_tree *tree;
377 struct rb_node *node;
378 struct btrfs_ordered_extent *entry = NULL;
379 unsigned long flags;
380 int ret;
381
382 tree = &BTRFS_I(inode)->ordered_tree;
383 spin_lock_irqsave(&tree->lock, flags);
384 if (cached && *cached) {
385 entry = *cached;
386 goto have_entry;
387 }
388
389 node = tree_search(tree, file_offset);
390 if (!node) {
391 ret = 1;
392 goto out;
393 }
394
395 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
396have_entry:
397 if (!offset_in_entry(entry, file_offset)) {
398 ret = 1;
399 goto out;
400 }
401
402 if (io_size > entry->bytes_left) {
403 btrfs_crit(BTRFS_I(inode)->root->fs_info,
404 "bad ordered accounting left %llu size %llu",
405 entry->bytes_left, io_size);
406 }
407 entry->bytes_left -= io_size;
408 if (!uptodate)
409 set_bit(BTRFS_ORDERED_IOERR, &entry->flags);
410
411 if (entry->bytes_left == 0) {
412 ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
413 /*
414 * Implicit memory barrier after test_and_set_bit
415 */
416 if (waitqueue_active(&entry->wait))
417 wake_up(&entry->wait);
418 } else {
419 ret = 1;
420 }
421out:
422 if (!ret && cached && entry) {
423 *cached = entry;
424 refcount_inc(&entry->refs);
425 }
426 spin_unlock_irqrestore(&tree->lock, flags);
427 return ret == 0;
428}
429
430/* Needs to either be called under a log transaction or the log_mutex */
431void btrfs_get_logged_extents(struct btrfs_inode *inode,
432 struct list_head *logged_list,
433 const loff_t start,
434 const loff_t end)
435{
436 struct btrfs_ordered_inode_tree *tree;
437 struct btrfs_ordered_extent *ordered;
438 struct rb_node *n;
439 struct rb_node *prev;
440
441 tree = &inode->ordered_tree;
442 spin_lock_irq(&tree->lock);
443 n = __tree_search(&tree->tree, end, &prev);
444 if (!n)
445 n = prev;
446 for (; n; n = rb_prev(n)) {
447 ordered = rb_entry(n, struct btrfs_ordered_extent, rb_node);
448 if (ordered->file_offset > end)
449 continue;
450 if (entry_end(ordered) <= start)
451 break;
452 if (test_and_set_bit(BTRFS_ORDERED_LOGGED, &ordered->flags))
453 continue;
454 list_add(&ordered->log_list, logged_list);
455 refcount_inc(&ordered->refs);
456 }
457 spin_unlock_irq(&tree->lock);
458}
459
460void btrfs_put_logged_extents(struct list_head *logged_list)
461{
462 struct btrfs_ordered_extent *ordered;
463
464 while (!list_empty(logged_list)) {
465 ordered = list_first_entry(logged_list,
466 struct btrfs_ordered_extent,
467 log_list);
468 list_del_init(&ordered->log_list);
469 btrfs_put_ordered_extent(ordered);
470 }
471}
472
473void btrfs_submit_logged_extents(struct list_head *logged_list,
474 struct btrfs_root *log)
475{
476 int index = log->log_transid % 2;
477
478 spin_lock_irq(&log->log_extents_lock[index]);
479 list_splice_tail(logged_list, &log->logged_list[index]);
480 spin_unlock_irq(&log->log_extents_lock[index]);
481}
482
483void btrfs_wait_logged_extents(struct btrfs_trans_handle *trans,
484 struct btrfs_root *log, u64 transid)
485{
486 struct btrfs_ordered_extent *ordered;
487 int index = transid % 2;
488
489 spin_lock_irq(&log->log_extents_lock[index]);
490 while (!list_empty(&log->logged_list[index])) {
491 struct inode *inode;
492 ordered = list_first_entry(&log->logged_list[index],
493 struct btrfs_ordered_extent,
494 log_list);
495 list_del_init(&ordered->log_list);
496 inode = ordered->inode;
497 spin_unlock_irq(&log->log_extents_lock[index]);
498
499 if (!test_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags) &&
500 !test_bit(BTRFS_ORDERED_DIRECT, &ordered->flags)) {
501 u64 start = ordered->file_offset;
502 u64 end = ordered->file_offset + ordered->len - 1;
503
504 WARN_ON(!inode);
505 filemap_fdatawrite_range(inode->i_mapping, start, end);
506 }
507 wait_event(ordered->wait, test_bit(BTRFS_ORDERED_IO_DONE,
508 &ordered->flags));
509
510 /*
511 * In order to keep us from losing our ordered extent
512 * information when committing the transaction we have to make
513 * sure that any logged extents are completed when we go to
514 * commit the transaction. To do this we simply increase the
515 * current transactions pending_ordered counter and decrement it
516 * when the ordered extent completes.
517 */
518 if (!test_bit(BTRFS_ORDERED_COMPLETE, &ordered->flags)) {
519 struct btrfs_ordered_inode_tree *tree;
520
521 tree = &BTRFS_I(inode)->ordered_tree;
522 spin_lock_irq(&tree->lock);
523 if (!test_bit(BTRFS_ORDERED_COMPLETE, &ordered->flags)) {
524 set_bit(BTRFS_ORDERED_PENDING, &ordered->flags);
525 atomic_inc(&trans->transaction->pending_ordered);
526 }
527 spin_unlock_irq(&tree->lock);
528 }
529 btrfs_put_ordered_extent(ordered);
530 spin_lock_irq(&log->log_extents_lock[index]);
531 }
532 spin_unlock_irq(&log->log_extents_lock[index]);
533}
534
535void btrfs_free_logged_extents(struct btrfs_root *log, u64 transid)
536{
537 struct btrfs_ordered_extent *ordered;
538 int index = transid % 2;
539
540 spin_lock_irq(&log->log_extents_lock[index]);
541 while (!list_empty(&log->logged_list[index])) {
542 ordered = list_first_entry(&log->logged_list[index],
543 struct btrfs_ordered_extent,
544 log_list);
545 list_del_init(&ordered->log_list);
546 spin_unlock_irq(&log->log_extents_lock[index]);
547 btrfs_put_ordered_extent(ordered);
548 spin_lock_irq(&log->log_extents_lock[index]);
549 }
550 spin_unlock_irq(&log->log_extents_lock[index]);
551}
552
553/*
554 * used to drop a reference on an ordered extent. This will free
555 * the extent if the last reference is dropped
556 */
557void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
558{
559 struct list_head *cur;
560 struct btrfs_ordered_sum *sum;
561
562 trace_btrfs_ordered_extent_put(entry->inode, entry);
563
564 if (refcount_dec_and_test(&entry->refs)) {
565 ASSERT(list_empty(&entry->log_list));
566 ASSERT(list_empty(&entry->trans_list));
567 ASSERT(list_empty(&entry->root_extent_list));
568 ASSERT(RB_EMPTY_NODE(&entry->rb_node));
569 if (entry->inode)
570 btrfs_add_delayed_iput(entry->inode);
571 while (!list_empty(&entry->list)) {
572 cur = entry->list.next;
573 sum = list_entry(cur, struct btrfs_ordered_sum, list);
574 list_del(&sum->list);
575 kfree(sum);
576 }
577 kmem_cache_free(btrfs_ordered_extent_cache, entry);
578 }
579}
580
581/*
582 * remove an ordered extent from the tree. No references are dropped
583 * and waiters are woken up.
584 */
585void btrfs_remove_ordered_extent(struct inode *inode,
586 struct btrfs_ordered_extent *entry)
587{
588 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
589 struct btrfs_ordered_inode_tree *tree;
590 struct btrfs_inode *btrfs_inode = BTRFS_I(inode);
591 struct btrfs_root *root = btrfs_inode->root;
592 struct rb_node *node;
593 bool dec_pending_ordered = false;
594
595 /* This is paired with btrfs_add_ordered_extent. */
596 spin_lock(&btrfs_inode->lock);
597 btrfs_mod_outstanding_extents(btrfs_inode, -1);
598 spin_unlock(&btrfs_inode->lock);
599 if (root != fs_info->tree_root)
600 btrfs_delalloc_release_metadata(btrfs_inode, entry->len, false);
601
602 tree = &btrfs_inode->ordered_tree;
603 spin_lock_irq(&tree->lock);
604 node = &entry->rb_node;
605 rb_erase(node, &tree->tree);
606 RB_CLEAR_NODE(node);
607 if (tree->last == node)
608 tree->last = NULL;
609 set_bit(BTRFS_ORDERED_COMPLETE, &entry->flags);
610 if (test_and_clear_bit(BTRFS_ORDERED_PENDING, &entry->flags))
611 dec_pending_ordered = true;
612 spin_unlock_irq(&tree->lock);
613
614 /*
615 * The current running transaction is waiting on us, we need to let it
616 * know that we're complete and wake it up.
617 */
618 if (dec_pending_ordered) {
619 struct btrfs_transaction *trans;
620
621 /*
622 * The checks for trans are just a formality, it should be set,
623 * but if it isn't we don't want to deref/assert under the spin
624 * lock, so be nice and check if trans is set, but ASSERT() so
625 * if it isn't set a developer will notice.
626 */
627 spin_lock(&fs_info->trans_lock);
628 trans = fs_info->running_transaction;
629 if (trans)
630 refcount_inc(&trans->use_count);
631 spin_unlock(&fs_info->trans_lock);
632
633 ASSERT(trans);
634 if (trans) {
635 if (atomic_dec_and_test(&trans->pending_ordered))
636 wake_up(&trans->pending_wait);
637 btrfs_put_transaction(trans);
638 }
639 }
640
641 spin_lock(&root->ordered_extent_lock);
642 list_del_init(&entry->root_extent_list);
643 root->nr_ordered_extents--;
644
645 trace_btrfs_ordered_extent_remove(inode, entry);
646
647 if (!root->nr_ordered_extents) {
648 spin_lock(&fs_info->ordered_root_lock);
649 BUG_ON(list_empty(&root->ordered_root));
650 list_del_init(&root->ordered_root);
651 spin_unlock(&fs_info->ordered_root_lock);
652 }
653 spin_unlock(&root->ordered_extent_lock);
654 wake_up(&entry->wait);
655}
656
657static void btrfs_run_ordered_extent_work(struct btrfs_work *work)
658{
659 struct btrfs_ordered_extent *ordered;
660
661 ordered = container_of(work, struct btrfs_ordered_extent, flush_work);
662 btrfs_start_ordered_extent(ordered->inode, ordered, 1);
663 complete(&ordered->completion);
664}
665
666/*
667 * wait for all the ordered extents in a root. This is done when balancing
668 * space between drives.
669 */
670u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,
671 const u64 range_start, const u64 range_len)
672{
673 struct btrfs_fs_info *fs_info = root->fs_info;
674 LIST_HEAD(splice);
675 LIST_HEAD(skipped);
676 LIST_HEAD(works);
677 struct btrfs_ordered_extent *ordered, *next;
678 u64 count = 0;
679 const u64 range_end = range_start + range_len;
680
681 mutex_lock(&root->ordered_extent_mutex);
682 spin_lock(&root->ordered_extent_lock);
683 list_splice_init(&root->ordered_extents, &splice);
684 while (!list_empty(&splice) && nr) {
685 ordered = list_first_entry(&splice, struct btrfs_ordered_extent,
686 root_extent_list);
687
688 if (range_end <= ordered->start ||
689 ordered->start + ordered->disk_len <= range_start) {
690 list_move_tail(&ordered->root_extent_list, &skipped);
691 cond_resched_lock(&root->ordered_extent_lock);
692 continue;
693 }
694
695 list_move_tail(&ordered->root_extent_list,
696 &root->ordered_extents);
697 refcount_inc(&ordered->refs);
698 spin_unlock(&root->ordered_extent_lock);
699
700 btrfs_init_work(&ordered->flush_work,
701 btrfs_flush_delalloc_helper,
702 btrfs_run_ordered_extent_work, NULL, NULL);
703 list_add_tail(&ordered->work_list, &works);
704 btrfs_queue_work(fs_info->flush_workers, &ordered->flush_work);
705
706 cond_resched();
707 spin_lock(&root->ordered_extent_lock);
708 if (nr != U64_MAX)
709 nr--;
710 count++;
711 }
712 list_splice_tail(&skipped, &root->ordered_extents);
713 list_splice_tail(&splice, &root->ordered_extents);
714 spin_unlock(&root->ordered_extent_lock);
715
716 list_for_each_entry_safe(ordered, next, &works, work_list) {
717 list_del_init(&ordered->work_list);
718 wait_for_completion(&ordered->completion);
719 btrfs_put_ordered_extent(ordered);
720 cond_resched();
721 }
722 mutex_unlock(&root->ordered_extent_mutex);
723
724 return count;
725}
726
727u64 btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,
728 const u64 range_start, const u64 range_len)
729{
730 struct btrfs_root *root;
731 struct list_head splice;
732 u64 total_done = 0;
733 u64 done;
734
735 INIT_LIST_HEAD(&splice);
736
737 mutex_lock(&fs_info->ordered_operations_mutex);
738 spin_lock(&fs_info->ordered_root_lock);
739 list_splice_init(&fs_info->ordered_roots, &splice);
740 while (!list_empty(&splice) && nr) {
741 root = list_first_entry(&splice, struct btrfs_root,
742 ordered_root);
743 root = btrfs_grab_fs_root(root);
744 BUG_ON(!root);
745 list_move_tail(&root->ordered_root,
746 &fs_info->ordered_roots);
747 spin_unlock(&fs_info->ordered_root_lock);
748
749 done = btrfs_wait_ordered_extents(root, nr,
750 range_start, range_len);
751 btrfs_put_fs_root(root);
752 total_done += done;
753
754 spin_lock(&fs_info->ordered_root_lock);
755 if (nr != U64_MAX) {
756 nr -= done;
757 }
758 }
759 list_splice_tail(&splice, &fs_info->ordered_roots);
760 spin_unlock(&fs_info->ordered_root_lock);
761 mutex_unlock(&fs_info->ordered_operations_mutex);
762
763 return total_done;
764}
765
766/*
767 * Used to start IO or wait for a given ordered extent to finish.
768 *
769 * If wait is one, this effectively waits on page writeback for all the pages
770 * in the extent, and it waits on the io completion code to insert
771 * metadata into the btree corresponding to the extent
772 */
773void btrfs_start_ordered_extent(struct inode *inode,
774 struct btrfs_ordered_extent *entry,
775 int wait)
776{
777 u64 start = entry->file_offset;
778 u64 end = start + entry->len - 1;
779
780 trace_btrfs_ordered_extent_start(inode, entry);
781
782 /*
783 * pages in the range can be dirty, clean or writeback. We
784 * start IO on any dirty ones so the wait doesn't stall waiting
785 * for the flusher thread to find them
786 */
787 if (!test_bit(BTRFS_ORDERED_DIRECT, &entry->flags))
788 filemap_fdatawrite_range(inode->i_mapping, start, end);
789 if (wait) {
790 wait_event(entry->wait, test_bit(BTRFS_ORDERED_COMPLETE,
791 &entry->flags));
792 }
793}
794
795/*
796 * Used to wait on ordered extents across a large range of bytes.
797 */
798int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len)
799{
800 int ret = 0;
801 int ret_wb = 0;
802 u64 end;
803 u64 orig_end;
804 struct btrfs_ordered_extent *ordered;
805
806 if (start + len < start) {
807 orig_end = INT_LIMIT(loff_t);
808 } else {
809 orig_end = start + len - 1;
810 if (orig_end > INT_LIMIT(loff_t))
811 orig_end = INT_LIMIT(loff_t);
812 }
813
814 /* start IO across the range first to instantiate any delalloc
815 * extents
816 */
817 ret = btrfs_fdatawrite_range(inode, start, orig_end);
818 if (ret)
819 return ret;
820
821 /*
822 * If we have a writeback error don't return immediately. Wait first
823 * for any ordered extents that haven't completed yet. This is to make
824 * sure no one can dirty the same page ranges and call writepages()
825 * before the ordered extents complete - to avoid failures (-EEXIST)
826 * when adding the new ordered extents to the ordered tree.
827 */
828 ret_wb = filemap_fdatawait_range(inode->i_mapping, start, orig_end);
829
830 end = orig_end;
831 while (1) {
832 ordered = btrfs_lookup_first_ordered_extent(inode, end);
833 if (!ordered)
834 break;
835 if (ordered->file_offset > orig_end) {
836 btrfs_put_ordered_extent(ordered);
837 break;
838 }
839 if (ordered->file_offset + ordered->len <= start) {
840 btrfs_put_ordered_extent(ordered);
841 break;
842 }
843 btrfs_start_ordered_extent(inode, ordered, 1);
844 end = ordered->file_offset;
845 if (test_bit(BTRFS_ORDERED_IOERR, &ordered->flags))
846 ret = -EIO;
847 btrfs_put_ordered_extent(ordered);
848 if (ret || end == 0 || end == start)
849 break;
850 end--;
851 }
852 return ret_wb ? ret_wb : ret;
853}
854
855/*
856 * find an ordered extent corresponding to file_offset. return NULL if
857 * nothing is found, otherwise take a reference on the extent and return it
858 */
859struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct inode *inode,
860 u64 file_offset)
861{
862 struct btrfs_ordered_inode_tree *tree;
863 struct rb_node *node;
864 struct btrfs_ordered_extent *entry = NULL;
865
866 tree = &BTRFS_I(inode)->ordered_tree;
867 spin_lock_irq(&tree->lock);
868 node = tree_search(tree, file_offset);
869 if (!node)
870 goto out;
871
872 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
873 if (!offset_in_entry(entry, file_offset))
874 entry = NULL;
875 if (entry)
876 refcount_inc(&entry->refs);
877out:
878 spin_unlock_irq(&tree->lock);
879 return entry;
880}
881
882/* Since the DIO code tries to lock a wide area we need to look for any ordered
883 * extents that exist in the range, rather than just the start of the range.
884 */
885struct btrfs_ordered_extent *btrfs_lookup_ordered_range(
886 struct btrfs_inode *inode, u64 file_offset, u64 len)
887{
888 struct btrfs_ordered_inode_tree *tree;
889 struct rb_node *node;
890 struct btrfs_ordered_extent *entry = NULL;
891
892 tree = &inode->ordered_tree;
893 spin_lock_irq(&tree->lock);
894 node = tree_search(tree, file_offset);
895 if (!node) {
896 node = tree_search(tree, file_offset + len);
897 if (!node)
898 goto out;
899 }
900
901 while (1) {
902 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
903 if (range_overlaps(entry, file_offset, len))
904 break;
905
906 if (entry->file_offset >= file_offset + len) {
907 entry = NULL;
908 break;
909 }
910 entry = NULL;
911 node = rb_next(node);
912 if (!node)
913 break;
914 }
915out:
916 if (entry)
917 refcount_inc(&entry->refs);
918 spin_unlock_irq(&tree->lock);
919 return entry;
920}
921
922bool btrfs_have_ordered_extents_in_range(struct inode *inode,
923 u64 file_offset,
924 u64 len)
925{
926 struct btrfs_ordered_extent *oe;
927
928 oe = btrfs_lookup_ordered_range(BTRFS_I(inode), file_offset, len);
929 if (oe) {
930 btrfs_put_ordered_extent(oe);
931 return true;
932 }
933 return false;
934}
935
936/*
937 * lookup and return any extent before 'file_offset'. NULL is returned
938 * if none is found
939 */
940struct btrfs_ordered_extent *
941btrfs_lookup_first_ordered_extent(struct inode *inode, u64 file_offset)
942{
943 struct btrfs_ordered_inode_tree *tree;
944 struct rb_node *node;
945 struct btrfs_ordered_extent *entry = NULL;
946
947 tree = &BTRFS_I(inode)->ordered_tree;
948 spin_lock_irq(&tree->lock);
949 node = tree_search(tree, file_offset);
950 if (!node)
951 goto out;
952
953 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
954 refcount_inc(&entry->refs);
955out:
956 spin_unlock_irq(&tree->lock);
957 return entry;
958}
959
960/*
961 * After an extent is done, call this to conditionally update the on disk
962 * i_size. i_size is updated to cover any fully written part of the file.
963 */
964int btrfs_ordered_update_i_size(struct inode *inode, u64 offset,
965 struct btrfs_ordered_extent *ordered)
966{
967 struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
968 u64 disk_i_size;
969 u64 new_i_size;
970 u64 i_size = i_size_read(inode);
971 struct rb_node *node;
972 struct rb_node *prev = NULL;
973 struct btrfs_ordered_extent *test;
974 int ret = 1;
975 u64 orig_offset = offset;
976
977 spin_lock_irq(&tree->lock);
978 if (ordered) {
979 offset = entry_end(ordered);
980 if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags))
981 offset = min(offset,
982 ordered->file_offset +
983 ordered->truncated_len);
984 } else {
985 offset = ALIGN(offset, btrfs_inode_sectorsize(inode));
986 }
987 disk_i_size = BTRFS_I(inode)->disk_i_size;
988
989 /*
990 * truncate file.
991 * If ordered is not NULL, then this is called from endio and
992 * disk_i_size will be updated by either truncate itself or any
993 * in-flight IOs which are inside the disk_i_size.
994 *
995 * Because btrfs_setsize() may set i_size with disk_i_size if truncate
996 * fails somehow, we need to make sure we have a precise disk_i_size by
997 * updating it as usual.
998 *
999 */
1000 if (!ordered && disk_i_size > i_size) {
1001 BTRFS_I(inode)->disk_i_size = orig_offset;
1002 ret = 0;
1003 goto out;
1004 }
1005
1006 /*
1007 * if the disk i_size is already at the inode->i_size, or
1008 * this ordered extent is inside the disk i_size, we're done
1009 */
1010 if (disk_i_size == i_size)
1011 goto out;
1012
1013 /*
1014 * We still need to update disk_i_size if outstanding_isize is greater
1015 * than disk_i_size.
1016 */
1017 if (offset <= disk_i_size &&
1018 (!ordered || ordered->outstanding_isize <= disk_i_size))
1019 goto out;
1020
1021 /*
1022 * walk backward from this ordered extent to disk_i_size.
1023 * if we find an ordered extent then we can't update disk i_size
1024 * yet
1025 */
1026 if (ordered) {
1027 node = rb_prev(&ordered->rb_node);
1028 } else {
1029 prev = tree_search(tree, offset);
1030 /*
1031 * we insert file extents without involving ordered struct,
1032 * so there should be no ordered struct cover this offset
1033 */
1034 if (prev) {
1035 test = rb_entry(prev, struct btrfs_ordered_extent,
1036 rb_node);
1037 BUG_ON(offset_in_entry(test, offset));
1038 }
1039 node = prev;
1040 }
1041 for (; node; node = rb_prev(node)) {
1042 test = rb_entry(node, struct btrfs_ordered_extent, rb_node);
1043
1044 /* We treat this entry as if it doesn't exist */
1045 if (test_bit(BTRFS_ORDERED_UPDATED_ISIZE, &test->flags))
1046 continue;
1047
1048 if (entry_end(test) <= disk_i_size)
1049 break;
1050 if (test->file_offset >= i_size)
1051 break;
1052
1053 /*
1054 * We don't update disk_i_size now, so record this undealt
1055 * i_size. Or we will not know the real i_size.
1056 */
1057 if (test->outstanding_isize < offset)
1058 test->outstanding_isize = offset;
1059 if (ordered &&
1060 ordered->outstanding_isize > test->outstanding_isize)
1061 test->outstanding_isize = ordered->outstanding_isize;
1062 goto out;
1063 }
1064 new_i_size = min_t(u64, offset, i_size);
1065
1066 /*
1067 * Some ordered extents may completed before the current one, and
1068 * we hold the real i_size in ->outstanding_isize.
1069 */
1070 if (ordered && ordered->outstanding_isize > new_i_size)
1071 new_i_size = min_t(u64, ordered->outstanding_isize, i_size);
1072 BTRFS_I(inode)->disk_i_size = new_i_size;
1073 ret = 0;
1074out:
1075 /*
1076 * We need to do this because we can't remove ordered extents until
1077 * after the i_disk_size has been updated and then the inode has been
1078 * updated to reflect the change, so we need to tell anybody who finds
1079 * this ordered extent that we've already done all the real work, we
1080 * just haven't completed all the other work.
1081 */
1082 if (ordered)
1083 set_bit(BTRFS_ORDERED_UPDATED_ISIZE, &ordered->flags);
1084 spin_unlock_irq(&tree->lock);
1085 return ret;
1086}
1087
1088/*
1089 * search the ordered extents for one corresponding to 'offset' and
1090 * try to find a checksum. This is used because we allow pages to
1091 * be reclaimed before their checksum is actually put into the btree
1092 */
1093int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
1094 u32 *sum, int len)
1095{
1096 struct btrfs_ordered_sum *ordered_sum;
1097 struct btrfs_ordered_extent *ordered;
1098 struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
1099 unsigned long num_sectors;
1100 unsigned long i;
1101 u32 sectorsize = btrfs_inode_sectorsize(inode);
1102 int index = 0;
1103
1104 ordered = btrfs_lookup_ordered_extent(inode, offset);
1105 if (!ordered)
1106 return 0;
1107
1108 spin_lock_irq(&tree->lock);
1109 list_for_each_entry_reverse(ordered_sum, &ordered->list, list) {
1110 if (disk_bytenr >= ordered_sum->bytenr &&
1111 disk_bytenr < ordered_sum->bytenr + ordered_sum->len) {
1112 i = (disk_bytenr - ordered_sum->bytenr) >>
1113 inode->i_sb->s_blocksize_bits;
1114 num_sectors = ordered_sum->len >>
1115 inode->i_sb->s_blocksize_bits;
1116 num_sectors = min_t(int, len - index, num_sectors - i);
1117 memcpy(sum + index, ordered_sum->sums + i,
1118 num_sectors);
1119
1120 index += (int)num_sectors;
1121 if (index == len)
1122 goto out;
1123 disk_bytenr += num_sectors * sectorsize;
1124 }
1125 }
1126out:
1127 spin_unlock_irq(&tree->lock);
1128 btrfs_put_ordered_extent(ordered);
1129 return index;
1130}
1131
1132int __init ordered_data_init(void)
1133{
1134 btrfs_ordered_extent_cache = kmem_cache_create("btrfs_ordered_extent",
1135 sizeof(struct btrfs_ordered_extent), 0,
1136 SLAB_MEM_SPREAD,
1137 NULL);
1138 if (!btrfs_ordered_extent_cache)
1139 return -ENOMEM;
1140
1141 return 0;
1142}
1143
1144void __cold ordered_data_exit(void)
1145{
1146 kmem_cache_destroy(btrfs_ordered_extent_cache);
1147}