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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 "messages.h"
11#include "misc.h"
12#include "ctree.h"
13#include "transaction.h"
14#include "btrfs_inode.h"
15#include "extent_io.h"
16#include "disk-io.h"
17#include "compression.h"
18#include "delalloc-space.h"
19#include "qgroup.h"
20#include "subpage.h"
21#include "file.h"
22#include "block-group.h"
23
24static struct kmem_cache *btrfs_ordered_extent_cache;
25
26static u64 entry_end(struct btrfs_ordered_extent *entry)
27{
28 if (entry->file_offset + entry->num_bytes < entry->file_offset)
29 return (u64)-1;
30 return entry->file_offset + entry->num_bytes;
31}
32
33/* returns NULL if the insertion worked, or it returns the node it did find
34 * in the tree
35 */
36static struct rb_node *tree_insert(struct rb_root *root, u64 file_offset,
37 struct rb_node *node)
38{
39 struct rb_node **p = &root->rb_node;
40 struct rb_node *parent = NULL;
41 struct btrfs_ordered_extent *entry;
42
43 while (*p) {
44 parent = *p;
45 entry = rb_entry(parent, struct btrfs_ordered_extent, rb_node);
46
47 if (file_offset < entry->file_offset)
48 p = &(*p)->rb_left;
49 else if (file_offset >= entry_end(entry))
50 p = &(*p)->rb_right;
51 else
52 return parent;
53 }
54
55 rb_link_node(node, parent, p);
56 rb_insert_color(node, root);
57 return NULL;
58}
59
60/*
61 * look for a given offset in the tree, and if it can't be found return the
62 * first lesser offset
63 */
64static struct rb_node *__tree_search(struct rb_root *root, u64 file_offset,
65 struct rb_node **prev_ret)
66{
67 struct rb_node *n = root->rb_node;
68 struct rb_node *prev = NULL;
69 struct rb_node *test;
70 struct btrfs_ordered_extent *entry;
71 struct btrfs_ordered_extent *prev_entry = NULL;
72
73 while (n) {
74 entry = rb_entry(n, struct btrfs_ordered_extent, rb_node);
75 prev = n;
76 prev_entry = entry;
77
78 if (file_offset < entry->file_offset)
79 n = n->rb_left;
80 else if (file_offset >= entry_end(entry))
81 n = n->rb_right;
82 else
83 return n;
84 }
85 if (!prev_ret)
86 return NULL;
87
88 while (prev && file_offset >= entry_end(prev_entry)) {
89 test = rb_next(prev);
90 if (!test)
91 break;
92 prev_entry = rb_entry(test, struct btrfs_ordered_extent,
93 rb_node);
94 if (file_offset < entry_end(prev_entry))
95 break;
96
97 prev = test;
98 }
99 if (prev)
100 prev_entry = rb_entry(prev, struct btrfs_ordered_extent,
101 rb_node);
102 while (prev && file_offset < entry_end(prev_entry)) {
103 test = rb_prev(prev);
104 if (!test)
105 break;
106 prev_entry = rb_entry(test, struct btrfs_ordered_extent,
107 rb_node);
108 prev = test;
109 }
110 *prev_ret = prev;
111 return NULL;
112}
113
114static int btrfs_range_overlaps(struct btrfs_ordered_extent *entry, u64 file_offset,
115 u64 len)
116{
117 if (file_offset + len <= entry->file_offset ||
118 entry->file_offset + entry->num_bytes <= file_offset)
119 return 0;
120 return 1;
121}
122
123/*
124 * look find the first ordered struct that has this offset, otherwise
125 * the first one less than this offset
126 */
127static inline struct rb_node *ordered_tree_search(struct btrfs_inode *inode,
128 u64 file_offset)
129{
130 struct rb_node *prev = NULL;
131 struct rb_node *ret;
132 struct btrfs_ordered_extent *entry;
133
134 if (inode->ordered_tree_last) {
135 entry = rb_entry(inode->ordered_tree_last, struct btrfs_ordered_extent,
136 rb_node);
137 if (in_range(file_offset, entry->file_offset, entry->num_bytes))
138 return inode->ordered_tree_last;
139 }
140 ret = __tree_search(&inode->ordered_tree, file_offset, &prev);
141 if (!ret)
142 ret = prev;
143 if (ret)
144 inode->ordered_tree_last = ret;
145 return ret;
146}
147
148static struct btrfs_ordered_extent *alloc_ordered_extent(
149 struct btrfs_inode *inode, u64 file_offset, u64 num_bytes,
150 u64 ram_bytes, u64 disk_bytenr, u64 disk_num_bytes,
151 u64 offset, unsigned long flags, int compress_type)
152{
153 struct btrfs_ordered_extent *entry;
154 int ret;
155 u64 qgroup_rsv = 0;
156
157 if (flags &
158 ((1 << BTRFS_ORDERED_NOCOW) | (1 << BTRFS_ORDERED_PREALLOC))) {
159 /* For nocow write, we can release the qgroup rsv right now */
160 ret = btrfs_qgroup_free_data(inode, NULL, file_offset, num_bytes, &qgroup_rsv);
161 if (ret < 0)
162 return ERR_PTR(ret);
163 } else {
164 /*
165 * The ordered extent has reserved qgroup space, release now
166 * and pass the reserved number for qgroup_record to free.
167 */
168 ret = btrfs_qgroup_release_data(inode, file_offset, num_bytes, &qgroup_rsv);
169 if (ret < 0)
170 return ERR_PTR(ret);
171 }
172 entry = kmem_cache_zalloc(btrfs_ordered_extent_cache, GFP_NOFS);
173 if (!entry)
174 return ERR_PTR(-ENOMEM);
175
176 entry->file_offset = file_offset;
177 entry->num_bytes = num_bytes;
178 entry->ram_bytes = ram_bytes;
179 entry->disk_bytenr = disk_bytenr;
180 entry->disk_num_bytes = disk_num_bytes;
181 entry->offset = offset;
182 entry->bytes_left = num_bytes;
183 entry->inode = BTRFS_I(igrab(&inode->vfs_inode));
184 entry->compress_type = compress_type;
185 entry->truncated_len = (u64)-1;
186 entry->qgroup_rsv = qgroup_rsv;
187 entry->flags = flags;
188 refcount_set(&entry->refs, 1);
189 init_waitqueue_head(&entry->wait);
190 INIT_LIST_HEAD(&entry->list);
191 INIT_LIST_HEAD(&entry->log_list);
192 INIT_LIST_HEAD(&entry->root_extent_list);
193 INIT_LIST_HEAD(&entry->work_list);
194 INIT_LIST_HEAD(&entry->bioc_list);
195 init_completion(&entry->completion);
196
197 /*
198 * We don't need the count_max_extents here, we can assume that all of
199 * that work has been done at higher layers, so this is truly the
200 * smallest the extent is going to get.
201 */
202 spin_lock(&inode->lock);
203 btrfs_mod_outstanding_extents(inode, 1);
204 spin_unlock(&inode->lock);
205
206 return entry;
207}
208
209static void insert_ordered_extent(struct btrfs_ordered_extent *entry)
210{
211 struct btrfs_inode *inode = entry->inode;
212 struct btrfs_root *root = inode->root;
213 struct btrfs_fs_info *fs_info = root->fs_info;
214 struct rb_node *node;
215
216 trace_btrfs_ordered_extent_add(inode, entry);
217
218 percpu_counter_add_batch(&fs_info->ordered_bytes, entry->num_bytes,
219 fs_info->delalloc_batch);
220
221 /* One ref for the tree. */
222 refcount_inc(&entry->refs);
223
224 spin_lock_irq(&inode->ordered_tree_lock);
225 node = tree_insert(&inode->ordered_tree, entry->file_offset,
226 &entry->rb_node);
227 if (unlikely(node))
228 btrfs_panic(fs_info, -EEXIST,
229 "inconsistency in ordered tree at offset %llu",
230 entry->file_offset);
231 spin_unlock_irq(&inode->ordered_tree_lock);
232
233 spin_lock(&root->ordered_extent_lock);
234 list_add_tail(&entry->root_extent_list,
235 &root->ordered_extents);
236 root->nr_ordered_extents++;
237 if (root->nr_ordered_extents == 1) {
238 spin_lock(&fs_info->ordered_root_lock);
239 BUG_ON(!list_empty(&root->ordered_root));
240 list_add_tail(&root->ordered_root, &fs_info->ordered_roots);
241 spin_unlock(&fs_info->ordered_root_lock);
242 }
243 spin_unlock(&root->ordered_extent_lock);
244}
245
246/*
247 * Add an ordered extent to the per-inode tree.
248 *
249 * @inode: Inode that this extent is for.
250 * @file_offset: Logical offset in file where the extent starts.
251 * @num_bytes: Logical length of extent in file.
252 * @ram_bytes: Full length of unencoded data.
253 * @disk_bytenr: Offset of extent on disk.
254 * @disk_num_bytes: Size of extent on disk.
255 * @offset: Offset into unencoded data where file data starts.
256 * @flags: Flags specifying type of extent (1 << BTRFS_ORDERED_*).
257 * @compress_type: Compression algorithm used for data.
258 *
259 * Most of these parameters correspond to &struct btrfs_file_extent_item. The
260 * tree is given a single reference on the ordered extent that was inserted, and
261 * the returned pointer is given a second reference.
262 *
263 * Return: the new ordered extent or error pointer.
264 */
265struct btrfs_ordered_extent *btrfs_alloc_ordered_extent(
266 struct btrfs_inode *inode, u64 file_offset,
267 const struct btrfs_file_extent *file_extent, unsigned long flags)
268{
269 struct btrfs_ordered_extent *entry;
270
271 ASSERT((flags & ~BTRFS_ORDERED_TYPE_FLAGS) == 0);
272
273 /*
274 * For regular writes, we just use the members in @file_extent.
275 *
276 * For NOCOW, we don't really care about the numbers except @start and
277 * file_extent->num_bytes, as we won't insert a file extent item at all.
278 *
279 * For PREALLOC, we do not use ordered extent members, but
280 * btrfs_mark_extent_written() handles everything.
281 *
282 * So here we always pass 0 as offset for NOCOW/PREALLOC ordered extents,
283 * or btrfs_split_ordered_extent() cannot handle it correctly.
284 */
285 if (flags & ((1U << BTRFS_ORDERED_NOCOW) | (1U << BTRFS_ORDERED_PREALLOC)))
286 entry = alloc_ordered_extent(inode, file_offset,
287 file_extent->num_bytes,
288 file_extent->num_bytes,
289 file_extent->disk_bytenr + file_extent->offset,
290 file_extent->num_bytes, 0, flags,
291 file_extent->compression);
292 else
293 entry = alloc_ordered_extent(inode, file_offset,
294 file_extent->num_bytes,
295 file_extent->ram_bytes,
296 file_extent->disk_bytenr,
297 file_extent->disk_num_bytes,
298 file_extent->offset, flags,
299 file_extent->compression);
300 if (!IS_ERR(entry))
301 insert_ordered_extent(entry);
302 return entry;
303}
304
305/*
306 * Add a struct btrfs_ordered_sum into the list of checksums to be inserted
307 * when an ordered extent is finished. If the list covers more than one
308 * ordered extent, it is split across multiples.
309 */
310void btrfs_add_ordered_sum(struct btrfs_ordered_extent *entry,
311 struct btrfs_ordered_sum *sum)
312{
313 struct btrfs_inode *inode = entry->inode;
314
315 spin_lock_irq(&inode->ordered_tree_lock);
316 list_add_tail(&sum->list, &entry->list);
317 spin_unlock_irq(&inode->ordered_tree_lock);
318}
319
320void btrfs_mark_ordered_extent_error(struct btrfs_ordered_extent *ordered)
321{
322 if (!test_and_set_bit(BTRFS_ORDERED_IOERR, &ordered->flags))
323 mapping_set_error(ordered->inode->vfs_inode.i_mapping, -EIO);
324}
325
326static void finish_ordered_fn(struct btrfs_work *work)
327{
328 struct btrfs_ordered_extent *ordered_extent;
329
330 ordered_extent = container_of(work, struct btrfs_ordered_extent, work);
331 btrfs_finish_ordered_io(ordered_extent);
332}
333
334static bool can_finish_ordered_extent(struct btrfs_ordered_extent *ordered,
335 struct folio *folio, u64 file_offset,
336 u64 len, bool uptodate)
337{
338 struct btrfs_inode *inode = ordered->inode;
339 struct btrfs_fs_info *fs_info = inode->root->fs_info;
340
341 lockdep_assert_held(&inode->ordered_tree_lock);
342
343 if (folio) {
344 ASSERT(folio->mapping);
345 ASSERT(folio_pos(folio) <= file_offset);
346 ASSERT(file_offset + len <= folio_pos(folio) + folio_size(folio));
347
348 /*
349 * Ordered flag indicates whether we still have
350 * pending io unfinished for the ordered extent.
351 *
352 * If it's not set, we need to skip to next range.
353 */
354 if (!btrfs_folio_test_ordered(fs_info, folio, file_offset, len))
355 return false;
356 btrfs_folio_clear_ordered(fs_info, folio, file_offset, len);
357 }
358
359 /* Now we're fine to update the accounting. */
360 if (WARN_ON_ONCE(len > ordered->bytes_left)) {
361 btrfs_crit(fs_info,
362"bad ordered extent accounting, root=%llu ino=%llu OE offset=%llu OE len=%llu to_dec=%llu left=%llu",
363 btrfs_root_id(inode->root), btrfs_ino(inode),
364 ordered->file_offset, ordered->num_bytes,
365 len, ordered->bytes_left);
366 ordered->bytes_left = 0;
367 } else {
368 ordered->bytes_left -= len;
369 }
370
371 if (!uptodate)
372 set_bit(BTRFS_ORDERED_IOERR, &ordered->flags);
373
374 if (ordered->bytes_left)
375 return false;
376
377 /*
378 * All the IO of the ordered extent is finished, we need to queue
379 * the finish_func to be executed.
380 */
381 set_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags);
382 cond_wake_up(&ordered->wait);
383 refcount_inc(&ordered->refs);
384 trace_btrfs_ordered_extent_mark_finished(inode, ordered);
385 return true;
386}
387
388static void btrfs_queue_ordered_fn(struct btrfs_ordered_extent *ordered)
389{
390 struct btrfs_inode *inode = ordered->inode;
391 struct btrfs_fs_info *fs_info = inode->root->fs_info;
392 struct btrfs_workqueue *wq = btrfs_is_free_space_inode(inode) ?
393 fs_info->endio_freespace_worker : fs_info->endio_write_workers;
394
395 btrfs_init_work(&ordered->work, finish_ordered_fn, NULL);
396 btrfs_queue_work(wq, &ordered->work);
397}
398
399void btrfs_finish_ordered_extent(struct btrfs_ordered_extent *ordered,
400 struct folio *folio, u64 file_offset, u64 len,
401 bool uptodate)
402{
403 struct btrfs_inode *inode = ordered->inode;
404 unsigned long flags;
405 bool ret;
406
407 trace_btrfs_finish_ordered_extent(inode, file_offset, len, uptodate);
408
409 spin_lock_irqsave(&inode->ordered_tree_lock, flags);
410 ret = can_finish_ordered_extent(ordered, folio, file_offset, len,
411 uptodate);
412 spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
413
414 /*
415 * If this is a COW write it means we created new extent maps for the
416 * range and they point to unwritten locations if we got an error either
417 * before submitting a bio or during IO.
418 *
419 * We have marked the ordered extent with BTRFS_ORDERED_IOERR, and we
420 * are queuing its completion below. During completion, at
421 * btrfs_finish_one_ordered(), we will drop the extent maps for the
422 * unwritten extents.
423 *
424 * However because completion runs in a work queue we can end up having
425 * a fast fsync running before that. In the case of direct IO, once we
426 * unlock the inode the fsync might start, and we queue the completion
427 * before unlocking the inode. In the case of buffered IO when writeback
428 * finishes (end_bbio_data_write()) we queue the completion, so if the
429 * writeback was triggered by a fast fsync, the fsync might start
430 * logging before ordered extent completion runs in the work queue.
431 *
432 * The fast fsync will log file extent items based on the extent maps it
433 * finds, so if by the time it collects extent maps the ordered extent
434 * completion didn't happen yet, it will log file extent items that
435 * point to unwritten extents, resulting in a corruption if a crash
436 * happens and the log tree is replayed. Note that a fast fsync does not
437 * wait for completion of ordered extents in order to reduce latency.
438 *
439 * Set a flag in the inode so that the next fast fsync will wait for
440 * ordered extents to complete before starting to log.
441 */
442 if (!uptodate && !test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags))
443 set_bit(BTRFS_INODE_COW_WRITE_ERROR, &inode->runtime_flags);
444
445 if (ret)
446 btrfs_queue_ordered_fn(ordered);
447}
448
449/*
450 * Mark all ordered extents io inside the specified range finished.
451 *
452 * @folio: The involved folio for the operation.
453 * For uncompressed buffered IO, the folio status also needs to be
454 * updated to indicate whether the pending ordered io is finished.
455 * Can be NULL for direct IO and compressed write.
456 * For these cases, callers are ensured they won't execute the
457 * endio function twice.
458 *
459 * This function is called for endio, thus the range must have ordered
460 * extent(s) covering it.
461 */
462void btrfs_mark_ordered_io_finished(struct btrfs_inode *inode,
463 struct folio *folio, u64 file_offset,
464 u64 num_bytes, bool uptodate)
465{
466 struct rb_node *node;
467 struct btrfs_ordered_extent *entry = NULL;
468 unsigned long flags;
469 u64 cur = file_offset;
470
471 trace_btrfs_writepage_end_io_hook(inode, file_offset,
472 file_offset + num_bytes - 1,
473 uptodate);
474
475 spin_lock_irqsave(&inode->ordered_tree_lock, flags);
476 while (cur < file_offset + num_bytes) {
477 u64 entry_end;
478 u64 end;
479 u32 len;
480
481 node = ordered_tree_search(inode, cur);
482 /* No ordered extents at all */
483 if (!node)
484 break;
485
486 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
487 entry_end = entry->file_offset + entry->num_bytes;
488 /*
489 * |<-- OE --->| |
490 * cur
491 * Go to next OE.
492 */
493 if (cur >= entry_end) {
494 node = rb_next(node);
495 /* No more ordered extents, exit */
496 if (!node)
497 break;
498 entry = rb_entry(node, struct btrfs_ordered_extent,
499 rb_node);
500
501 /* Go to next ordered extent and continue */
502 cur = entry->file_offset;
503 continue;
504 }
505 /*
506 * | |<--- OE --->|
507 * cur
508 * Go to the start of OE.
509 */
510 if (cur < entry->file_offset) {
511 cur = entry->file_offset;
512 continue;
513 }
514
515 /*
516 * Now we are definitely inside one ordered extent.
517 *
518 * |<--- OE --->|
519 * |
520 * cur
521 */
522 end = min(entry->file_offset + entry->num_bytes,
523 file_offset + num_bytes) - 1;
524 ASSERT(end + 1 - cur < U32_MAX);
525 len = end + 1 - cur;
526
527 if (can_finish_ordered_extent(entry, folio, cur, len, uptodate)) {
528 spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
529 btrfs_queue_ordered_fn(entry);
530 spin_lock_irqsave(&inode->ordered_tree_lock, flags);
531 }
532 cur += len;
533 }
534 spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
535}
536
537/*
538 * Finish IO for one ordered extent across a given range. The range can only
539 * contain one ordered extent.
540 *
541 * @cached: The cached ordered extent. If not NULL, we can skip the tree
542 * search and use the ordered extent directly.
543 * Will be also used to store the finished ordered extent.
544 * @file_offset: File offset for the finished IO
545 * @io_size: Length of the finish IO range
546 *
547 * Return true if the ordered extent is finished in the range, and update
548 * @cached.
549 * Return false otherwise.
550 *
551 * NOTE: The range can NOT cross multiple ordered extents.
552 * Thus caller should ensure the range doesn't cross ordered extents.
553 */
554bool btrfs_dec_test_ordered_pending(struct btrfs_inode *inode,
555 struct btrfs_ordered_extent **cached,
556 u64 file_offset, u64 io_size)
557{
558 struct rb_node *node;
559 struct btrfs_ordered_extent *entry = NULL;
560 unsigned long flags;
561 bool finished = false;
562
563 spin_lock_irqsave(&inode->ordered_tree_lock, flags);
564 if (cached && *cached) {
565 entry = *cached;
566 goto have_entry;
567 }
568
569 node = ordered_tree_search(inode, file_offset);
570 if (!node)
571 goto out;
572
573 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
574have_entry:
575 if (!in_range(file_offset, entry->file_offset, entry->num_bytes))
576 goto out;
577
578 if (io_size > entry->bytes_left)
579 btrfs_crit(inode->root->fs_info,
580 "bad ordered accounting left %llu size %llu",
581 entry->bytes_left, io_size);
582
583 entry->bytes_left -= io_size;
584
585 if (entry->bytes_left == 0) {
586 /*
587 * Ensure only one caller can set the flag and finished_ret
588 * accordingly
589 */
590 finished = !test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
591 /* test_and_set_bit implies a barrier */
592 cond_wake_up_nomb(&entry->wait);
593 }
594out:
595 if (finished && cached && entry) {
596 *cached = entry;
597 refcount_inc(&entry->refs);
598 trace_btrfs_ordered_extent_dec_test_pending(inode, entry);
599 }
600 spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
601 return finished;
602}
603
604/*
605 * used to drop a reference on an ordered extent. This will free
606 * the extent if the last reference is dropped
607 */
608void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
609{
610 struct list_head *cur;
611 struct btrfs_ordered_sum *sum;
612
613 trace_btrfs_ordered_extent_put(entry->inode, entry);
614
615 if (refcount_dec_and_test(&entry->refs)) {
616 ASSERT(list_empty(&entry->root_extent_list));
617 ASSERT(list_empty(&entry->log_list));
618 ASSERT(RB_EMPTY_NODE(&entry->rb_node));
619 if (entry->inode)
620 btrfs_add_delayed_iput(entry->inode);
621 while (!list_empty(&entry->list)) {
622 cur = entry->list.next;
623 sum = list_entry(cur, struct btrfs_ordered_sum, list);
624 list_del(&sum->list);
625 kvfree(sum);
626 }
627 kmem_cache_free(btrfs_ordered_extent_cache, entry);
628 }
629}
630
631/*
632 * remove an ordered extent from the tree. No references are dropped
633 * and waiters are woken up.
634 */
635void btrfs_remove_ordered_extent(struct btrfs_inode *btrfs_inode,
636 struct btrfs_ordered_extent *entry)
637{
638 struct btrfs_root *root = btrfs_inode->root;
639 struct btrfs_fs_info *fs_info = root->fs_info;
640 struct rb_node *node;
641 bool pending;
642 bool freespace_inode;
643
644 /*
645 * If this is a free space inode the thread has not acquired the ordered
646 * extents lockdep map.
647 */
648 freespace_inode = btrfs_is_free_space_inode(btrfs_inode);
649
650 btrfs_lockdep_acquire(fs_info, btrfs_trans_pending_ordered);
651 /* This is paired with alloc_ordered_extent(). */
652 spin_lock(&btrfs_inode->lock);
653 btrfs_mod_outstanding_extents(btrfs_inode, -1);
654 spin_unlock(&btrfs_inode->lock);
655 if (root != fs_info->tree_root) {
656 u64 release;
657
658 if (test_bit(BTRFS_ORDERED_ENCODED, &entry->flags))
659 release = entry->disk_num_bytes;
660 else
661 release = entry->num_bytes;
662 btrfs_delalloc_release_metadata(btrfs_inode, release,
663 test_bit(BTRFS_ORDERED_IOERR,
664 &entry->flags));
665 }
666
667 percpu_counter_add_batch(&fs_info->ordered_bytes, -entry->num_bytes,
668 fs_info->delalloc_batch);
669
670 spin_lock_irq(&btrfs_inode->ordered_tree_lock);
671 node = &entry->rb_node;
672 rb_erase(node, &btrfs_inode->ordered_tree);
673 RB_CLEAR_NODE(node);
674 if (btrfs_inode->ordered_tree_last == node)
675 btrfs_inode->ordered_tree_last = NULL;
676 set_bit(BTRFS_ORDERED_COMPLETE, &entry->flags);
677 pending = test_and_clear_bit(BTRFS_ORDERED_PENDING, &entry->flags);
678 spin_unlock_irq(&btrfs_inode->ordered_tree_lock);
679
680 /*
681 * The current running transaction is waiting on us, we need to let it
682 * know that we're complete and wake it up.
683 */
684 if (pending) {
685 struct btrfs_transaction *trans;
686
687 /*
688 * The checks for trans are just a formality, it should be set,
689 * but if it isn't we don't want to deref/assert under the spin
690 * lock, so be nice and check if trans is set, but ASSERT() so
691 * if it isn't set a developer will notice.
692 */
693 spin_lock(&fs_info->trans_lock);
694 trans = fs_info->running_transaction;
695 if (trans)
696 refcount_inc(&trans->use_count);
697 spin_unlock(&fs_info->trans_lock);
698
699 ASSERT(trans || BTRFS_FS_ERROR(fs_info));
700 if (trans) {
701 if (atomic_dec_and_test(&trans->pending_ordered))
702 wake_up(&trans->pending_wait);
703 btrfs_put_transaction(trans);
704 }
705 }
706
707 btrfs_lockdep_release(fs_info, btrfs_trans_pending_ordered);
708
709 spin_lock(&root->ordered_extent_lock);
710 list_del_init(&entry->root_extent_list);
711 root->nr_ordered_extents--;
712
713 trace_btrfs_ordered_extent_remove(btrfs_inode, entry);
714
715 if (!root->nr_ordered_extents) {
716 spin_lock(&fs_info->ordered_root_lock);
717 BUG_ON(list_empty(&root->ordered_root));
718 list_del_init(&root->ordered_root);
719 spin_unlock(&fs_info->ordered_root_lock);
720 }
721 spin_unlock(&root->ordered_extent_lock);
722 wake_up(&entry->wait);
723 if (!freespace_inode)
724 btrfs_lockdep_release(fs_info, btrfs_ordered_extent);
725}
726
727static void btrfs_run_ordered_extent_work(struct btrfs_work *work)
728{
729 struct btrfs_ordered_extent *ordered;
730
731 ordered = container_of(work, struct btrfs_ordered_extent, flush_work);
732 btrfs_start_ordered_extent(ordered);
733 complete(&ordered->completion);
734}
735
736/*
737 * Wait for all the ordered extents in a root. Use @bg as range or do whole
738 * range if it's NULL.
739 */
740u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,
741 const struct btrfs_block_group *bg)
742{
743 struct btrfs_fs_info *fs_info = root->fs_info;
744 LIST_HEAD(splice);
745 LIST_HEAD(skipped);
746 LIST_HEAD(works);
747 struct btrfs_ordered_extent *ordered, *next;
748 u64 count = 0;
749 u64 range_start, range_len;
750 u64 range_end;
751
752 if (bg) {
753 range_start = bg->start;
754 range_len = bg->length;
755 } else {
756 range_start = 0;
757 range_len = U64_MAX;
758 }
759 range_end = range_start + range_len;
760
761 mutex_lock(&root->ordered_extent_mutex);
762 spin_lock(&root->ordered_extent_lock);
763 list_splice_init(&root->ordered_extents, &splice);
764 while (!list_empty(&splice) && nr) {
765 ordered = list_first_entry(&splice, struct btrfs_ordered_extent,
766 root_extent_list);
767
768 if (range_end <= ordered->disk_bytenr ||
769 ordered->disk_bytenr + ordered->disk_num_bytes <= range_start) {
770 list_move_tail(&ordered->root_extent_list, &skipped);
771 cond_resched_lock(&root->ordered_extent_lock);
772 continue;
773 }
774
775 list_move_tail(&ordered->root_extent_list,
776 &root->ordered_extents);
777 refcount_inc(&ordered->refs);
778 spin_unlock(&root->ordered_extent_lock);
779
780 btrfs_init_work(&ordered->flush_work,
781 btrfs_run_ordered_extent_work, NULL);
782 list_add_tail(&ordered->work_list, &works);
783 btrfs_queue_work(fs_info->flush_workers, &ordered->flush_work);
784
785 cond_resched();
786 if (nr != U64_MAX)
787 nr--;
788 count++;
789 spin_lock(&root->ordered_extent_lock);
790 }
791 list_splice_tail(&skipped, &root->ordered_extents);
792 list_splice_tail(&splice, &root->ordered_extents);
793 spin_unlock(&root->ordered_extent_lock);
794
795 list_for_each_entry_safe(ordered, next, &works, work_list) {
796 list_del_init(&ordered->work_list);
797 wait_for_completion(&ordered->completion);
798 btrfs_put_ordered_extent(ordered);
799 cond_resched();
800 }
801 mutex_unlock(&root->ordered_extent_mutex);
802
803 return count;
804}
805
806/*
807 * Wait for @nr ordered extents that intersect the @bg, or the whole range of
808 * the filesystem if @bg is NULL.
809 */
810void btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,
811 const struct btrfs_block_group *bg)
812{
813 struct btrfs_root *root;
814 LIST_HEAD(splice);
815 u64 done;
816
817 mutex_lock(&fs_info->ordered_operations_mutex);
818 spin_lock(&fs_info->ordered_root_lock);
819 list_splice_init(&fs_info->ordered_roots, &splice);
820 while (!list_empty(&splice) && nr) {
821 root = list_first_entry(&splice, struct btrfs_root,
822 ordered_root);
823 root = btrfs_grab_root(root);
824 BUG_ON(!root);
825 list_move_tail(&root->ordered_root,
826 &fs_info->ordered_roots);
827 spin_unlock(&fs_info->ordered_root_lock);
828
829 done = btrfs_wait_ordered_extents(root, nr, bg);
830 btrfs_put_root(root);
831
832 if (nr != U64_MAX)
833 nr -= done;
834
835 spin_lock(&fs_info->ordered_root_lock);
836 }
837 list_splice_tail(&splice, &fs_info->ordered_roots);
838 spin_unlock(&fs_info->ordered_root_lock);
839 mutex_unlock(&fs_info->ordered_operations_mutex);
840}
841
842/*
843 * Start IO and wait for a given ordered extent to finish.
844 *
845 * Wait on page writeback for all the pages in the extent and the IO completion
846 * code to insert metadata into the btree corresponding to the extent.
847 */
848void btrfs_start_ordered_extent(struct btrfs_ordered_extent *entry)
849{
850 u64 start = entry->file_offset;
851 u64 end = start + entry->num_bytes - 1;
852 struct btrfs_inode *inode = entry->inode;
853 bool freespace_inode;
854
855 trace_btrfs_ordered_extent_start(inode, entry);
856
857 /*
858 * If this is a free space inode do not take the ordered extents lockdep
859 * map.
860 */
861 freespace_inode = btrfs_is_free_space_inode(inode);
862
863 /*
864 * pages in the range can be dirty, clean or writeback. We
865 * start IO on any dirty ones so the wait doesn't stall waiting
866 * for the flusher thread to find them
867 */
868 if (!test_bit(BTRFS_ORDERED_DIRECT, &entry->flags))
869 filemap_fdatawrite_range(inode->vfs_inode.i_mapping, start, end);
870
871 if (!freespace_inode)
872 btrfs_might_wait_for_event(inode->root->fs_info, btrfs_ordered_extent);
873 wait_event(entry->wait, test_bit(BTRFS_ORDERED_COMPLETE, &entry->flags));
874}
875
876/*
877 * Used to wait on ordered extents across a large range of bytes.
878 */
879int btrfs_wait_ordered_range(struct btrfs_inode *inode, u64 start, u64 len)
880{
881 int ret = 0;
882 int ret_wb = 0;
883 u64 end;
884 u64 orig_end;
885 struct btrfs_ordered_extent *ordered;
886
887 if (start + len < start) {
888 orig_end = OFFSET_MAX;
889 } else {
890 orig_end = start + len - 1;
891 if (orig_end > OFFSET_MAX)
892 orig_end = OFFSET_MAX;
893 }
894
895 /* start IO across the range first to instantiate any delalloc
896 * extents
897 */
898 ret = btrfs_fdatawrite_range(inode, start, orig_end);
899 if (ret)
900 return ret;
901
902 /*
903 * If we have a writeback error don't return immediately. Wait first
904 * for any ordered extents that haven't completed yet. This is to make
905 * sure no one can dirty the same page ranges and call writepages()
906 * before the ordered extents complete - to avoid failures (-EEXIST)
907 * when adding the new ordered extents to the ordered tree.
908 */
909 ret_wb = filemap_fdatawait_range(inode->vfs_inode.i_mapping, start, orig_end);
910
911 end = orig_end;
912 while (1) {
913 ordered = btrfs_lookup_first_ordered_extent(inode, end);
914 if (!ordered)
915 break;
916 if (ordered->file_offset > orig_end) {
917 btrfs_put_ordered_extent(ordered);
918 break;
919 }
920 if (ordered->file_offset + ordered->num_bytes <= start) {
921 btrfs_put_ordered_extent(ordered);
922 break;
923 }
924 btrfs_start_ordered_extent(ordered);
925 end = ordered->file_offset;
926 /*
927 * If the ordered extent had an error save the error but don't
928 * exit without waiting first for all other ordered extents in
929 * the range to complete.
930 */
931 if (test_bit(BTRFS_ORDERED_IOERR, &ordered->flags))
932 ret = -EIO;
933 btrfs_put_ordered_extent(ordered);
934 if (end == 0 || end == start)
935 break;
936 end--;
937 }
938 return ret_wb ? ret_wb : ret;
939}
940
941/*
942 * find an ordered extent corresponding to file_offset. return NULL if
943 * nothing is found, otherwise take a reference on the extent and return it
944 */
945struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct btrfs_inode *inode,
946 u64 file_offset)
947{
948 struct rb_node *node;
949 struct btrfs_ordered_extent *entry = NULL;
950 unsigned long flags;
951
952 spin_lock_irqsave(&inode->ordered_tree_lock, flags);
953 node = ordered_tree_search(inode, file_offset);
954 if (!node)
955 goto out;
956
957 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
958 if (!in_range(file_offset, entry->file_offset, entry->num_bytes))
959 entry = NULL;
960 if (entry) {
961 refcount_inc(&entry->refs);
962 trace_btrfs_ordered_extent_lookup(inode, entry);
963 }
964out:
965 spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
966 return entry;
967}
968
969/* Since the DIO code tries to lock a wide area we need to look for any ordered
970 * extents that exist in the range, rather than just the start of the range.
971 */
972struct btrfs_ordered_extent *btrfs_lookup_ordered_range(
973 struct btrfs_inode *inode, u64 file_offset, u64 len)
974{
975 struct rb_node *node;
976 struct btrfs_ordered_extent *entry = NULL;
977
978 spin_lock_irq(&inode->ordered_tree_lock);
979 node = ordered_tree_search(inode, file_offset);
980 if (!node) {
981 node = ordered_tree_search(inode, file_offset + len);
982 if (!node)
983 goto out;
984 }
985
986 while (1) {
987 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
988 if (btrfs_range_overlaps(entry, file_offset, len))
989 break;
990
991 if (entry->file_offset >= file_offset + len) {
992 entry = NULL;
993 break;
994 }
995 entry = NULL;
996 node = rb_next(node);
997 if (!node)
998 break;
999 }
1000out:
1001 if (entry) {
1002 refcount_inc(&entry->refs);
1003 trace_btrfs_ordered_extent_lookup_range(inode, entry);
1004 }
1005 spin_unlock_irq(&inode->ordered_tree_lock);
1006 return entry;
1007}
1008
1009/*
1010 * Adds all ordered extents to the given list. The list ends up sorted by the
1011 * file_offset of the ordered extents.
1012 */
1013void btrfs_get_ordered_extents_for_logging(struct btrfs_inode *inode,
1014 struct list_head *list)
1015{
1016 struct rb_node *n;
1017
1018 btrfs_assert_inode_locked(inode);
1019
1020 spin_lock_irq(&inode->ordered_tree_lock);
1021 for (n = rb_first(&inode->ordered_tree); n; n = rb_next(n)) {
1022 struct btrfs_ordered_extent *ordered;
1023
1024 ordered = rb_entry(n, struct btrfs_ordered_extent, rb_node);
1025
1026 if (test_bit(BTRFS_ORDERED_LOGGED, &ordered->flags))
1027 continue;
1028
1029 ASSERT(list_empty(&ordered->log_list));
1030 list_add_tail(&ordered->log_list, list);
1031 refcount_inc(&ordered->refs);
1032 trace_btrfs_ordered_extent_lookup_for_logging(inode, ordered);
1033 }
1034 spin_unlock_irq(&inode->ordered_tree_lock);
1035}
1036
1037/*
1038 * lookup and return any extent before 'file_offset'. NULL is returned
1039 * if none is found
1040 */
1041struct btrfs_ordered_extent *
1042btrfs_lookup_first_ordered_extent(struct btrfs_inode *inode, u64 file_offset)
1043{
1044 struct rb_node *node;
1045 struct btrfs_ordered_extent *entry = NULL;
1046
1047 spin_lock_irq(&inode->ordered_tree_lock);
1048 node = ordered_tree_search(inode, file_offset);
1049 if (!node)
1050 goto out;
1051
1052 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
1053 refcount_inc(&entry->refs);
1054 trace_btrfs_ordered_extent_lookup_first(inode, entry);
1055out:
1056 spin_unlock_irq(&inode->ordered_tree_lock);
1057 return entry;
1058}
1059
1060/*
1061 * Lookup the first ordered extent that overlaps the range
1062 * [@file_offset, @file_offset + @len).
1063 *
1064 * The difference between this and btrfs_lookup_first_ordered_extent() is
1065 * that this one won't return any ordered extent that does not overlap the range.
1066 * And the difference against btrfs_lookup_ordered_extent() is, this function
1067 * ensures the first ordered extent gets returned.
1068 */
1069struct btrfs_ordered_extent *btrfs_lookup_first_ordered_range(
1070 struct btrfs_inode *inode, u64 file_offset, u64 len)
1071{
1072 struct rb_node *node;
1073 struct rb_node *cur;
1074 struct rb_node *prev;
1075 struct rb_node *next;
1076 struct btrfs_ordered_extent *entry = NULL;
1077
1078 spin_lock_irq(&inode->ordered_tree_lock);
1079 node = inode->ordered_tree.rb_node;
1080 /*
1081 * Here we don't want to use tree_search() which will use tree->last
1082 * and screw up the search order.
1083 * And __tree_search() can't return the adjacent ordered extents
1084 * either, thus here we do our own search.
1085 */
1086 while (node) {
1087 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
1088
1089 if (file_offset < entry->file_offset) {
1090 node = node->rb_left;
1091 } else if (file_offset >= entry_end(entry)) {
1092 node = node->rb_right;
1093 } else {
1094 /*
1095 * Direct hit, got an ordered extent that starts at
1096 * @file_offset
1097 */
1098 goto out;
1099 }
1100 }
1101 if (!entry) {
1102 /* Empty tree */
1103 goto out;
1104 }
1105
1106 cur = &entry->rb_node;
1107 /* We got an entry around @file_offset, check adjacent entries */
1108 if (entry->file_offset < file_offset) {
1109 prev = cur;
1110 next = rb_next(cur);
1111 } else {
1112 prev = rb_prev(cur);
1113 next = cur;
1114 }
1115 if (prev) {
1116 entry = rb_entry(prev, struct btrfs_ordered_extent, rb_node);
1117 if (btrfs_range_overlaps(entry, file_offset, len))
1118 goto out;
1119 }
1120 if (next) {
1121 entry = rb_entry(next, struct btrfs_ordered_extent, rb_node);
1122 if (btrfs_range_overlaps(entry, file_offset, len))
1123 goto out;
1124 }
1125 /* No ordered extent in the range */
1126 entry = NULL;
1127out:
1128 if (entry) {
1129 refcount_inc(&entry->refs);
1130 trace_btrfs_ordered_extent_lookup_first_range(inode, entry);
1131 }
1132
1133 spin_unlock_irq(&inode->ordered_tree_lock);
1134 return entry;
1135}
1136
1137/*
1138 * Lock the passed range and ensures all pending ordered extents in it are run
1139 * to completion.
1140 *
1141 * @inode: Inode whose ordered tree is to be searched
1142 * @start: Beginning of range to flush
1143 * @end: Last byte of range to lock
1144 * @cached_state: If passed, will return the extent state responsible for the
1145 * locked range. It's the caller's responsibility to free the
1146 * cached state.
1147 *
1148 * Always return with the given range locked, ensuring after it's called no
1149 * order extent can be pending.
1150 */
1151void btrfs_lock_and_flush_ordered_range(struct btrfs_inode *inode, u64 start,
1152 u64 end,
1153 struct extent_state **cached_state)
1154{
1155 struct btrfs_ordered_extent *ordered;
1156 struct extent_state *cache = NULL;
1157 struct extent_state **cachedp = &cache;
1158
1159 if (cached_state)
1160 cachedp = cached_state;
1161
1162 while (1) {
1163 lock_extent(&inode->io_tree, start, end, cachedp);
1164 ordered = btrfs_lookup_ordered_range(inode, start,
1165 end - start + 1);
1166 if (!ordered) {
1167 /*
1168 * If no external cached_state has been passed then
1169 * decrement the extra ref taken for cachedp since we
1170 * aren't exposing it outside of this function
1171 */
1172 if (!cached_state)
1173 refcount_dec(&cache->refs);
1174 break;
1175 }
1176 unlock_extent(&inode->io_tree, start, end, cachedp);
1177 btrfs_start_ordered_extent(ordered);
1178 btrfs_put_ordered_extent(ordered);
1179 }
1180}
1181
1182/*
1183 * Lock the passed range and ensure all pending ordered extents in it are run
1184 * to completion in nowait mode.
1185 *
1186 * Return true if btrfs_lock_ordered_range does not return any extents,
1187 * otherwise false.
1188 */
1189bool btrfs_try_lock_ordered_range(struct btrfs_inode *inode, u64 start, u64 end,
1190 struct extent_state **cached_state)
1191{
1192 struct btrfs_ordered_extent *ordered;
1193
1194 if (!try_lock_extent(&inode->io_tree, start, end, cached_state))
1195 return false;
1196
1197 ordered = btrfs_lookup_ordered_range(inode, start, end - start + 1);
1198 if (!ordered)
1199 return true;
1200
1201 btrfs_put_ordered_extent(ordered);
1202 unlock_extent(&inode->io_tree, start, end, cached_state);
1203
1204 return false;
1205}
1206
1207/* Split out a new ordered extent for this first @len bytes of @ordered. */
1208struct btrfs_ordered_extent *btrfs_split_ordered_extent(
1209 struct btrfs_ordered_extent *ordered, u64 len)
1210{
1211 struct btrfs_inode *inode = ordered->inode;
1212 struct btrfs_root *root = inode->root;
1213 struct btrfs_fs_info *fs_info = root->fs_info;
1214 u64 file_offset = ordered->file_offset;
1215 u64 disk_bytenr = ordered->disk_bytenr;
1216 unsigned long flags = ordered->flags;
1217 struct btrfs_ordered_sum *sum, *tmpsum;
1218 struct btrfs_ordered_extent *new;
1219 struct rb_node *node;
1220 u64 offset = 0;
1221
1222 trace_btrfs_ordered_extent_split(inode, ordered);
1223
1224 ASSERT(!(flags & (1U << BTRFS_ORDERED_COMPRESSED)));
1225
1226 /*
1227 * The entire bio must be covered by the ordered extent, but we can't
1228 * reduce the original extent to a zero length either.
1229 */
1230 if (WARN_ON_ONCE(len >= ordered->num_bytes))
1231 return ERR_PTR(-EINVAL);
1232 /*
1233 * If our ordered extent had an error there's no point in continuing.
1234 * The error may have come from a transaction abort done either by this
1235 * task or some other concurrent task, and the transaction abort path
1236 * iterates over all existing ordered extents and sets the flag
1237 * BTRFS_ORDERED_IOERR on them.
1238 */
1239 if (unlikely(flags & (1U << BTRFS_ORDERED_IOERR))) {
1240 const int fs_error = BTRFS_FS_ERROR(fs_info);
1241
1242 return fs_error ? ERR_PTR(fs_error) : ERR_PTR(-EIO);
1243 }
1244 /* We cannot split partially completed ordered extents. */
1245 if (ordered->bytes_left) {
1246 ASSERT(!(flags & ~BTRFS_ORDERED_TYPE_FLAGS));
1247 if (WARN_ON_ONCE(ordered->bytes_left != ordered->disk_num_bytes))
1248 return ERR_PTR(-EINVAL);
1249 }
1250 /* We cannot split a compressed ordered extent. */
1251 if (WARN_ON_ONCE(ordered->disk_num_bytes != ordered->num_bytes))
1252 return ERR_PTR(-EINVAL);
1253
1254 new = alloc_ordered_extent(inode, file_offset, len, len, disk_bytenr,
1255 len, 0, flags, ordered->compress_type);
1256 if (IS_ERR(new))
1257 return new;
1258
1259 /* One ref for the tree. */
1260 refcount_inc(&new->refs);
1261
1262 /*
1263 * Take the root's ordered_extent_lock to avoid a race with
1264 * btrfs_wait_ordered_extents() when updating the disk_bytenr and
1265 * disk_num_bytes fields of the ordered extent below. And we disable
1266 * IRQs because the inode's ordered_tree_lock is used in IRQ context
1267 * elsewhere.
1268 *
1269 * There's no concern about a previous caller of
1270 * btrfs_wait_ordered_extents() getting the trimmed ordered extent
1271 * before we insert the new one, because even if it gets the ordered
1272 * extent before it's trimmed and the new one inserted, right before it
1273 * uses it or during its use, the ordered extent might have been
1274 * trimmed in the meanwhile, and it missed the new ordered extent.
1275 * There's no way around this and it's harmless for current use cases,
1276 * so we take the root's ordered_extent_lock to fix that race during
1277 * trimming and silence tools like KCSAN.
1278 */
1279 spin_lock_irq(&root->ordered_extent_lock);
1280 spin_lock(&inode->ordered_tree_lock);
1281
1282 /*
1283 * We don't have overlapping ordered extents (that would imply double
1284 * allocation of extents) and we checked above that the split length
1285 * does not cross the ordered extent's num_bytes field, so there's
1286 * no need to remove it and re-insert it in the tree.
1287 */
1288 ordered->file_offset += len;
1289 ordered->disk_bytenr += len;
1290 ordered->num_bytes -= len;
1291 ordered->disk_num_bytes -= len;
1292 ordered->ram_bytes -= len;
1293
1294 if (test_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags)) {
1295 ASSERT(ordered->bytes_left == 0);
1296 new->bytes_left = 0;
1297 } else {
1298 ordered->bytes_left -= len;
1299 }
1300
1301 if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags)) {
1302 if (ordered->truncated_len > len) {
1303 ordered->truncated_len -= len;
1304 } else {
1305 new->truncated_len = ordered->truncated_len;
1306 ordered->truncated_len = 0;
1307 }
1308 }
1309
1310 list_for_each_entry_safe(sum, tmpsum, &ordered->list, list) {
1311 if (offset == len)
1312 break;
1313 list_move_tail(&sum->list, &new->list);
1314 offset += sum->len;
1315 }
1316
1317 node = tree_insert(&inode->ordered_tree, new->file_offset, &new->rb_node);
1318 if (unlikely(node))
1319 btrfs_panic(fs_info, -EEXIST,
1320 "inconsistency in ordered tree at offset %llu after split",
1321 new->file_offset);
1322 spin_unlock(&inode->ordered_tree_lock);
1323
1324 list_add_tail(&new->root_extent_list, &root->ordered_extents);
1325 root->nr_ordered_extents++;
1326 spin_unlock_irq(&root->ordered_extent_lock);
1327 return new;
1328}
1329
1330int __init ordered_data_init(void)
1331{
1332 btrfs_ordered_extent_cache = KMEM_CACHE(btrfs_ordered_extent, 0);
1333 if (!btrfs_ordered_extent_cache)
1334 return -ENOMEM;
1335
1336 return 0;
1337}
1338
1339void __cold ordered_data_exit(void)
1340{
1341 kmem_cache_destroy(btrfs_ordered_extent_cache);
1342}
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#include "compression.h"
29
30static struct kmem_cache *btrfs_ordered_extent_cache;
31
32static u64 entry_end(struct btrfs_ordered_extent *entry)
33{
34 if (entry->file_offset + entry->len < entry->file_offset)
35 return (u64)-1;
36 return entry->file_offset + entry->len;
37}
38
39/* returns NULL if the insertion worked, or it returns the node it did find
40 * in the tree
41 */
42static struct rb_node *tree_insert(struct rb_root *root, u64 file_offset,
43 struct rb_node *node)
44{
45 struct rb_node **p = &root->rb_node;
46 struct rb_node *parent = NULL;
47 struct btrfs_ordered_extent *entry;
48
49 while (*p) {
50 parent = *p;
51 entry = rb_entry(parent, struct btrfs_ordered_extent, rb_node);
52
53 if (file_offset < entry->file_offset)
54 p = &(*p)->rb_left;
55 else if (file_offset >= entry_end(entry))
56 p = &(*p)->rb_right;
57 else
58 return parent;
59 }
60
61 rb_link_node(node, parent, p);
62 rb_insert_color(node, root);
63 return NULL;
64}
65
66static void ordered_data_tree_panic(struct inode *inode, int errno,
67 u64 offset)
68{
69 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
70 btrfs_panic(fs_info, errno,
71 "Inconsistency in ordered tree at offset %llu", offset);
72}
73
74/*
75 * look for a given offset in the tree, and if it can't be found return the
76 * first lesser offset
77 */
78static struct rb_node *__tree_search(struct rb_root *root, u64 file_offset,
79 struct rb_node **prev_ret)
80{
81 struct rb_node *n = root->rb_node;
82 struct rb_node *prev = NULL;
83 struct rb_node *test;
84 struct btrfs_ordered_extent *entry;
85 struct btrfs_ordered_extent *prev_entry = NULL;
86
87 while (n) {
88 entry = rb_entry(n, struct btrfs_ordered_extent, rb_node);
89 prev = n;
90 prev_entry = entry;
91
92 if (file_offset < entry->file_offset)
93 n = n->rb_left;
94 else if (file_offset >= entry_end(entry))
95 n = n->rb_right;
96 else
97 return n;
98 }
99 if (!prev_ret)
100 return NULL;
101
102 while (prev && file_offset >= entry_end(prev_entry)) {
103 test = rb_next(prev);
104 if (!test)
105 break;
106 prev_entry = rb_entry(test, struct btrfs_ordered_extent,
107 rb_node);
108 if (file_offset < entry_end(prev_entry))
109 break;
110
111 prev = test;
112 }
113 if (prev)
114 prev_entry = rb_entry(prev, struct btrfs_ordered_extent,
115 rb_node);
116 while (prev && file_offset < entry_end(prev_entry)) {
117 test = rb_prev(prev);
118 if (!test)
119 break;
120 prev_entry = rb_entry(test, struct btrfs_ordered_extent,
121 rb_node);
122 prev = test;
123 }
124 *prev_ret = prev;
125 return NULL;
126}
127
128/*
129 * helper to check if a given offset is inside a given entry
130 */
131static int offset_in_entry(struct btrfs_ordered_extent *entry, u64 file_offset)
132{
133 if (file_offset < entry->file_offset ||
134 entry->file_offset + entry->len <= file_offset)
135 return 0;
136 return 1;
137}
138
139static int range_overlaps(struct btrfs_ordered_extent *entry, u64 file_offset,
140 u64 len)
141{
142 if (file_offset + len <= entry->file_offset ||
143 entry->file_offset + entry->len <= file_offset)
144 return 0;
145 return 1;
146}
147
148/*
149 * look find the first ordered struct that has this offset, otherwise
150 * the first one less than this offset
151 */
152static inline struct rb_node *tree_search(struct btrfs_ordered_inode_tree *tree,
153 u64 file_offset)
154{
155 struct rb_root *root = &tree->tree;
156 struct rb_node *prev = NULL;
157 struct rb_node *ret;
158 struct btrfs_ordered_extent *entry;
159
160 if (tree->last) {
161 entry = rb_entry(tree->last, struct btrfs_ordered_extent,
162 rb_node);
163 if (offset_in_entry(entry, file_offset))
164 return tree->last;
165 }
166 ret = __tree_search(root, file_offset, &prev);
167 if (!ret)
168 ret = prev;
169 if (ret)
170 tree->last = ret;
171 return ret;
172}
173
174/* allocate and add a new ordered_extent into the per-inode tree.
175 * file_offset is the logical offset in the file
176 *
177 * start is the disk block number of an extent already reserved in the
178 * extent allocation tree
179 *
180 * len is the length of the extent
181 *
182 * The tree is given a single reference on the ordered extent that was
183 * inserted.
184 */
185static int __btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
186 u64 start, u64 len, u64 disk_len,
187 int type, int dio, int compress_type)
188{
189 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
190 struct btrfs_root *root = BTRFS_I(inode)->root;
191 struct btrfs_ordered_inode_tree *tree;
192 struct rb_node *node;
193 struct btrfs_ordered_extent *entry;
194
195 tree = &BTRFS_I(inode)->ordered_tree;
196 entry = kmem_cache_zalloc(btrfs_ordered_extent_cache, GFP_NOFS);
197 if (!entry)
198 return -ENOMEM;
199
200 entry->file_offset = file_offset;
201 entry->start = start;
202 entry->len = len;
203 entry->disk_len = disk_len;
204 entry->bytes_left = len;
205 entry->inode = igrab(inode);
206 entry->compress_type = compress_type;
207 entry->truncated_len = (u64)-1;
208 if (type != BTRFS_ORDERED_IO_DONE && type != BTRFS_ORDERED_COMPLETE)
209 set_bit(type, &entry->flags);
210
211 if (dio)
212 set_bit(BTRFS_ORDERED_DIRECT, &entry->flags);
213
214 /* one ref for the tree */
215 atomic_set(&entry->refs, 1);
216 init_waitqueue_head(&entry->wait);
217 INIT_LIST_HEAD(&entry->list);
218 INIT_LIST_HEAD(&entry->root_extent_list);
219 INIT_LIST_HEAD(&entry->work_list);
220 init_completion(&entry->completion);
221 INIT_LIST_HEAD(&entry->log_list);
222 INIT_LIST_HEAD(&entry->trans_list);
223
224 trace_btrfs_ordered_extent_add(inode, entry);
225
226 spin_lock_irq(&tree->lock);
227 node = tree_insert(&tree->tree, file_offset,
228 &entry->rb_node);
229 if (node)
230 ordered_data_tree_panic(inode, -EEXIST, file_offset);
231 spin_unlock_irq(&tree->lock);
232
233 spin_lock(&root->ordered_extent_lock);
234 list_add_tail(&entry->root_extent_list,
235 &root->ordered_extents);
236 root->nr_ordered_extents++;
237 if (root->nr_ordered_extents == 1) {
238 spin_lock(&fs_info->ordered_root_lock);
239 BUG_ON(!list_empty(&root->ordered_root));
240 list_add_tail(&root->ordered_root, &fs_info->ordered_roots);
241 spin_unlock(&fs_info->ordered_root_lock);
242 }
243 spin_unlock(&root->ordered_extent_lock);
244
245 return 0;
246}
247
248int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
249 u64 start, u64 len, u64 disk_len, int type)
250{
251 return __btrfs_add_ordered_extent(inode, file_offset, start, len,
252 disk_len, type, 0,
253 BTRFS_COMPRESS_NONE);
254}
255
256int btrfs_add_ordered_extent_dio(struct inode *inode, u64 file_offset,
257 u64 start, u64 len, u64 disk_len, int type)
258{
259 return __btrfs_add_ordered_extent(inode, file_offset, start, len,
260 disk_len, type, 1,
261 BTRFS_COMPRESS_NONE);
262}
263
264int btrfs_add_ordered_extent_compress(struct inode *inode, u64 file_offset,
265 u64 start, u64 len, u64 disk_len,
266 int type, int compress_type)
267{
268 return __btrfs_add_ordered_extent(inode, file_offset, start, len,
269 disk_len, type, 0,
270 compress_type);
271}
272
273/*
274 * Add a struct btrfs_ordered_sum into the list of checksums to be inserted
275 * when an ordered extent is finished. If the list covers more than one
276 * ordered extent, it is split across multiples.
277 */
278void btrfs_add_ordered_sum(struct inode *inode,
279 struct btrfs_ordered_extent *entry,
280 struct btrfs_ordered_sum *sum)
281{
282 struct btrfs_ordered_inode_tree *tree;
283
284 tree = &BTRFS_I(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 /*
351 * Implicit memory barrier after test_and_set_bit
352 */
353 if (waitqueue_active(&entry->wait))
354 wake_up(&entry->wait);
355 } else {
356 ret = 1;
357 }
358out:
359 if (!ret && cached && entry) {
360 *cached = entry;
361 atomic_inc(&entry->refs);
362 }
363 spin_unlock_irqrestore(&tree->lock, flags);
364 return ret == 0;
365}
366
367/*
368 * this is used to account for finished IO across a given range
369 * of the file. The IO should not span ordered extents. If
370 * a given ordered_extent is completely done, 1 is returned, otherwise
371 * 0.
372 *
373 * test_and_set_bit on a flag in the struct btrfs_ordered_extent is used
374 * to make sure this function only returns 1 once for a given ordered extent.
375 */
376int btrfs_dec_test_ordered_pending(struct inode *inode,
377 struct btrfs_ordered_extent **cached,
378 u64 file_offset, u64 io_size, int uptodate)
379{
380 struct btrfs_ordered_inode_tree *tree;
381 struct rb_node *node;
382 struct btrfs_ordered_extent *entry = NULL;
383 unsigned long flags;
384 int ret;
385
386 tree = &BTRFS_I(inode)->ordered_tree;
387 spin_lock_irqsave(&tree->lock, flags);
388 if (cached && *cached) {
389 entry = *cached;
390 goto have_entry;
391 }
392
393 node = tree_search(tree, file_offset);
394 if (!node) {
395 ret = 1;
396 goto out;
397 }
398
399 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
400have_entry:
401 if (!offset_in_entry(entry, file_offset)) {
402 ret = 1;
403 goto out;
404 }
405
406 if (io_size > entry->bytes_left) {
407 btrfs_crit(BTRFS_I(inode)->root->fs_info,
408 "bad ordered accounting left %llu size %llu",
409 entry->bytes_left, io_size);
410 }
411 entry->bytes_left -= io_size;
412 if (!uptodate)
413 set_bit(BTRFS_ORDERED_IOERR, &entry->flags);
414
415 if (entry->bytes_left == 0) {
416 ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
417 /*
418 * Implicit memory barrier after test_and_set_bit
419 */
420 if (waitqueue_active(&entry->wait))
421 wake_up(&entry->wait);
422 } else {
423 ret = 1;
424 }
425out:
426 if (!ret && cached && entry) {
427 *cached = entry;
428 atomic_inc(&entry->refs);
429 }
430 spin_unlock_irqrestore(&tree->lock, flags);
431 return ret == 0;
432}
433
434/* Needs to either be called under a log transaction or the log_mutex */
435void btrfs_get_logged_extents(struct inode *inode,
436 struct list_head *logged_list,
437 const loff_t start,
438 const loff_t end)
439{
440 struct btrfs_ordered_inode_tree *tree;
441 struct btrfs_ordered_extent *ordered;
442 struct rb_node *n;
443 struct rb_node *prev;
444
445 tree = &BTRFS_I(inode)->ordered_tree;
446 spin_lock_irq(&tree->lock);
447 n = __tree_search(&tree->tree, end, &prev);
448 if (!n)
449 n = prev;
450 for (; n; n = rb_prev(n)) {
451 ordered = rb_entry(n, struct btrfs_ordered_extent, rb_node);
452 if (ordered->file_offset > end)
453 continue;
454 if (entry_end(ordered) <= start)
455 break;
456 if (test_and_set_bit(BTRFS_ORDERED_LOGGED, &ordered->flags))
457 continue;
458 list_add(&ordered->log_list, logged_list);
459 atomic_inc(&ordered->refs);
460 }
461 spin_unlock_irq(&tree->lock);
462}
463
464void btrfs_put_logged_extents(struct list_head *logged_list)
465{
466 struct btrfs_ordered_extent *ordered;
467
468 while (!list_empty(logged_list)) {
469 ordered = list_first_entry(logged_list,
470 struct btrfs_ordered_extent,
471 log_list);
472 list_del_init(&ordered->log_list);
473 btrfs_put_ordered_extent(ordered);
474 }
475}
476
477void btrfs_submit_logged_extents(struct list_head *logged_list,
478 struct btrfs_root *log)
479{
480 int index = log->log_transid % 2;
481
482 spin_lock_irq(&log->log_extents_lock[index]);
483 list_splice_tail(logged_list, &log->logged_list[index]);
484 spin_unlock_irq(&log->log_extents_lock[index]);
485}
486
487void btrfs_wait_logged_extents(struct btrfs_trans_handle *trans,
488 struct btrfs_root *log, u64 transid)
489{
490 struct btrfs_ordered_extent *ordered;
491 int index = transid % 2;
492
493 spin_lock_irq(&log->log_extents_lock[index]);
494 while (!list_empty(&log->logged_list[index])) {
495 struct inode *inode;
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 inode = ordered->inode;
501 spin_unlock_irq(&log->log_extents_lock[index]);
502
503 if (!test_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags) &&
504 !test_bit(BTRFS_ORDERED_DIRECT, &ordered->flags)) {
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 /*
515 * In order to keep us from losing our ordered extent
516 * information when committing the transaction we have to make
517 * sure that any logged extents are completed when we go to
518 * commit the transaction. To do this we simply increase the
519 * current transactions pending_ordered counter and decrement it
520 * when the ordered extent completes.
521 */
522 if (!test_bit(BTRFS_ORDERED_COMPLETE, &ordered->flags)) {
523 struct btrfs_ordered_inode_tree *tree;
524
525 tree = &BTRFS_I(inode)->ordered_tree;
526 spin_lock_irq(&tree->lock);
527 if (!test_bit(BTRFS_ORDERED_COMPLETE, &ordered->flags)) {
528 set_bit(BTRFS_ORDERED_PENDING, &ordered->flags);
529 atomic_inc(&trans->transaction->pending_ordered);
530 }
531 spin_unlock_irq(&tree->lock);
532 }
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
539void btrfs_free_logged_extents(struct btrfs_root *log, u64 transid)
540{
541 struct btrfs_ordered_extent *ordered;
542 int index = transid % 2;
543
544 spin_lock_irq(&log->log_extents_lock[index]);
545 while (!list_empty(&log->logged_list[index])) {
546 ordered = list_first_entry(&log->logged_list[index],
547 struct btrfs_ordered_extent,
548 log_list);
549 list_del_init(&ordered->log_list);
550 spin_unlock_irq(&log->log_extents_lock[index]);
551 btrfs_put_ordered_extent(ordered);
552 spin_lock_irq(&log->log_extents_lock[index]);
553 }
554 spin_unlock_irq(&log->log_extents_lock[index]);
555}
556
557/*
558 * used to drop a reference on an ordered extent. This will free
559 * the extent if the last reference is dropped
560 */
561void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
562{
563 struct list_head *cur;
564 struct btrfs_ordered_sum *sum;
565
566 trace_btrfs_ordered_extent_put(entry->inode, entry);
567
568 if (atomic_dec_and_test(&entry->refs)) {
569 ASSERT(list_empty(&entry->log_list));
570 ASSERT(list_empty(&entry->trans_list));
571 ASSERT(list_empty(&entry->root_extent_list));
572 ASSERT(RB_EMPTY_NODE(&entry->rb_node));
573 if (entry->inode)
574 btrfs_add_delayed_iput(entry->inode);
575 while (!list_empty(&entry->list)) {
576 cur = entry->list.next;
577 sum = list_entry(cur, struct btrfs_ordered_sum, list);
578 list_del(&sum->list);
579 kfree(sum);
580 }
581 kmem_cache_free(btrfs_ordered_extent_cache, entry);
582 }
583}
584
585/*
586 * remove an ordered extent from the tree. No references are dropped
587 * and waiters are woken up.
588 */
589void btrfs_remove_ordered_extent(struct inode *inode,
590 struct btrfs_ordered_extent *entry)
591{
592 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
593 struct btrfs_ordered_inode_tree *tree;
594 struct btrfs_root *root = BTRFS_I(inode)->root;
595 struct rb_node *node;
596 bool dec_pending_ordered = false;
597
598 tree = &BTRFS_I(inode)->ordered_tree;
599 spin_lock_irq(&tree->lock);
600 node = &entry->rb_node;
601 rb_erase(node, &tree->tree);
602 RB_CLEAR_NODE(node);
603 if (tree->last == node)
604 tree->last = NULL;
605 set_bit(BTRFS_ORDERED_COMPLETE, &entry->flags);
606 if (test_and_clear_bit(BTRFS_ORDERED_PENDING, &entry->flags))
607 dec_pending_ordered = true;
608 spin_unlock_irq(&tree->lock);
609
610 /*
611 * The current running transaction is waiting on us, we need to let it
612 * know that we're complete and wake it up.
613 */
614 if (dec_pending_ordered) {
615 struct btrfs_transaction *trans;
616
617 /*
618 * The checks for trans are just a formality, it should be set,
619 * but if it isn't we don't want to deref/assert under the spin
620 * lock, so be nice and check if trans is set, but ASSERT() so
621 * if it isn't set a developer will notice.
622 */
623 spin_lock(&fs_info->trans_lock);
624 trans = fs_info->running_transaction;
625 if (trans)
626 atomic_inc(&trans->use_count);
627 spin_unlock(&fs_info->trans_lock);
628
629 ASSERT(trans);
630 if (trans) {
631 if (atomic_dec_and_test(&trans->pending_ordered))
632 wake_up(&trans->pending_wait);
633 btrfs_put_transaction(trans);
634 }
635 }
636
637 spin_lock(&root->ordered_extent_lock);
638 list_del_init(&entry->root_extent_list);
639 root->nr_ordered_extents--;
640
641 trace_btrfs_ordered_extent_remove(inode, entry);
642
643 if (!root->nr_ordered_extents) {
644 spin_lock(&fs_info->ordered_root_lock);
645 BUG_ON(list_empty(&root->ordered_root));
646 list_del_init(&root->ordered_root);
647 spin_unlock(&fs_info->ordered_root_lock);
648 }
649 spin_unlock(&root->ordered_extent_lock);
650 wake_up(&entry->wait);
651}
652
653static void btrfs_run_ordered_extent_work(struct btrfs_work *work)
654{
655 struct btrfs_ordered_extent *ordered;
656
657 ordered = container_of(work, struct btrfs_ordered_extent, flush_work);
658 btrfs_start_ordered_extent(ordered->inode, ordered, 1);
659 complete(&ordered->completion);
660}
661
662/*
663 * wait for all the ordered extents in a root. This is done when balancing
664 * space between drives.
665 */
666int btrfs_wait_ordered_extents(struct btrfs_root *root, int nr,
667 const u64 range_start, const u64 range_len)
668{
669 struct btrfs_fs_info *fs_info = root->fs_info;
670 LIST_HEAD(splice);
671 LIST_HEAD(skipped);
672 LIST_HEAD(works);
673 struct btrfs_ordered_extent *ordered, *next;
674 int count = 0;
675 const u64 range_end = range_start + range_len;
676
677 mutex_lock(&root->ordered_extent_mutex);
678 spin_lock(&root->ordered_extent_lock);
679 list_splice_init(&root->ordered_extents, &splice);
680 while (!list_empty(&splice) && nr) {
681 ordered = list_first_entry(&splice, struct btrfs_ordered_extent,
682 root_extent_list);
683
684 if (range_end <= ordered->start ||
685 ordered->start + ordered->disk_len <= range_start) {
686 list_move_tail(&ordered->root_extent_list, &skipped);
687 cond_resched_lock(&root->ordered_extent_lock);
688 continue;
689 }
690
691 list_move_tail(&ordered->root_extent_list,
692 &root->ordered_extents);
693 atomic_inc(&ordered->refs);
694 spin_unlock(&root->ordered_extent_lock);
695
696 btrfs_init_work(&ordered->flush_work,
697 btrfs_flush_delalloc_helper,
698 btrfs_run_ordered_extent_work, NULL, NULL);
699 list_add_tail(&ordered->work_list, &works);
700 btrfs_queue_work(fs_info->flush_workers, &ordered->flush_work);
701
702 cond_resched();
703 spin_lock(&root->ordered_extent_lock);
704 if (nr != -1)
705 nr--;
706 count++;
707 }
708 list_splice_tail(&skipped, &root->ordered_extents);
709 list_splice_tail(&splice, &root->ordered_extents);
710 spin_unlock(&root->ordered_extent_lock);
711
712 list_for_each_entry_safe(ordered, next, &works, work_list) {
713 list_del_init(&ordered->work_list);
714 wait_for_completion(&ordered->completion);
715 btrfs_put_ordered_extent(ordered);
716 cond_resched();
717 }
718 mutex_unlock(&root->ordered_extent_mutex);
719
720 return count;
721}
722
723int btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, int nr,
724 const u64 range_start, const u64 range_len)
725{
726 struct btrfs_root *root;
727 struct list_head splice;
728 int done;
729 int total_done = 0;
730
731 INIT_LIST_HEAD(&splice);
732
733 mutex_lock(&fs_info->ordered_operations_mutex);
734 spin_lock(&fs_info->ordered_root_lock);
735 list_splice_init(&fs_info->ordered_roots, &splice);
736 while (!list_empty(&splice) && nr) {
737 root = list_first_entry(&splice, struct btrfs_root,
738 ordered_root);
739 root = btrfs_grab_fs_root(root);
740 BUG_ON(!root);
741 list_move_tail(&root->ordered_root,
742 &fs_info->ordered_roots);
743 spin_unlock(&fs_info->ordered_root_lock);
744
745 done = btrfs_wait_ordered_extents(root, nr,
746 range_start, range_len);
747 btrfs_put_fs_root(root);
748 total_done += done;
749
750 spin_lock(&fs_info->ordered_root_lock);
751 if (nr != -1) {
752 nr -= done;
753 WARN_ON(nr < 0);
754 }
755 }
756 list_splice_tail(&splice, &fs_info->ordered_roots);
757 spin_unlock(&fs_info->ordered_root_lock);
758 mutex_unlock(&fs_info->ordered_operations_mutex);
759
760 return total_done;
761}
762
763/*
764 * Used to start IO or wait for a given ordered extent to finish.
765 *
766 * If wait is one, this effectively waits on page writeback for all the pages
767 * in the extent, and it waits on the io completion code to insert
768 * metadata into the btree corresponding to the extent
769 */
770void btrfs_start_ordered_extent(struct inode *inode,
771 struct btrfs_ordered_extent *entry,
772 int wait)
773{
774 u64 start = entry->file_offset;
775 u64 end = start + entry->len - 1;
776
777 trace_btrfs_ordered_extent_start(inode, entry);
778
779 /*
780 * pages in the range can be dirty, clean or writeback. We
781 * start IO on any dirty ones so the wait doesn't stall waiting
782 * for the flusher thread to find them
783 */
784 if (!test_bit(BTRFS_ORDERED_DIRECT, &entry->flags))
785 filemap_fdatawrite_range(inode->i_mapping, start, end);
786 if (wait) {
787 wait_event(entry->wait, test_bit(BTRFS_ORDERED_COMPLETE,
788 &entry->flags));
789 }
790}
791
792/*
793 * Used to wait on ordered extents across a large range of bytes.
794 */
795int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len)
796{
797 int ret = 0;
798 int ret_wb = 0;
799 u64 end;
800 u64 orig_end;
801 struct btrfs_ordered_extent *ordered;
802
803 if (start + len < start) {
804 orig_end = INT_LIMIT(loff_t);
805 } else {
806 orig_end = start + len - 1;
807 if (orig_end > INT_LIMIT(loff_t))
808 orig_end = INT_LIMIT(loff_t);
809 }
810
811 /* start IO across the range first to instantiate any delalloc
812 * extents
813 */
814 ret = btrfs_fdatawrite_range(inode, start, orig_end);
815 if (ret)
816 return ret;
817
818 /*
819 * If we have a writeback error don't return immediately. Wait first
820 * for any ordered extents that haven't completed yet. This is to make
821 * sure no one can dirty the same page ranges and call writepages()
822 * before the ordered extents complete - to avoid failures (-EEXIST)
823 * when adding the new ordered extents to the ordered tree.
824 */
825 ret_wb = filemap_fdatawait_range(inode->i_mapping, start, orig_end);
826
827 end = orig_end;
828 while (1) {
829 ordered = btrfs_lookup_first_ordered_extent(inode, end);
830 if (!ordered)
831 break;
832 if (ordered->file_offset > orig_end) {
833 btrfs_put_ordered_extent(ordered);
834 break;
835 }
836 if (ordered->file_offset + ordered->len <= start) {
837 btrfs_put_ordered_extent(ordered);
838 break;
839 }
840 btrfs_start_ordered_extent(inode, ordered, 1);
841 end = ordered->file_offset;
842 if (test_bit(BTRFS_ORDERED_IOERR, &ordered->flags))
843 ret = -EIO;
844 btrfs_put_ordered_extent(ordered);
845 if (ret || end == 0 || end == start)
846 break;
847 end--;
848 }
849 return ret_wb ? ret_wb : ret;
850}
851
852/*
853 * find an ordered extent corresponding to file_offset. return NULL if
854 * nothing is found, otherwise take a reference on the extent and return it
855 */
856struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct inode *inode,
857 u64 file_offset)
858{
859 struct btrfs_ordered_inode_tree *tree;
860 struct rb_node *node;
861 struct btrfs_ordered_extent *entry = NULL;
862
863 tree = &BTRFS_I(inode)->ordered_tree;
864 spin_lock_irq(&tree->lock);
865 node = tree_search(tree, file_offset);
866 if (!node)
867 goto out;
868
869 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
870 if (!offset_in_entry(entry, file_offset))
871 entry = NULL;
872 if (entry)
873 atomic_inc(&entry->refs);
874out:
875 spin_unlock_irq(&tree->lock);
876 return entry;
877}
878
879/* Since the DIO code tries to lock a wide area we need to look for any ordered
880 * extents that exist in the range, rather than just the start of the range.
881 */
882struct btrfs_ordered_extent *btrfs_lookup_ordered_range(struct inode *inode,
883 u64 file_offset,
884 u64 len)
885{
886 struct btrfs_ordered_inode_tree *tree;
887 struct rb_node *node;
888 struct btrfs_ordered_extent *entry = NULL;
889
890 tree = &BTRFS_I(inode)->ordered_tree;
891 spin_lock_irq(&tree->lock);
892 node = tree_search(tree, file_offset);
893 if (!node) {
894 node = tree_search(tree, file_offset + len);
895 if (!node)
896 goto out;
897 }
898
899 while (1) {
900 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
901 if (range_overlaps(entry, file_offset, len))
902 break;
903
904 if (entry->file_offset >= file_offset + len) {
905 entry = NULL;
906 break;
907 }
908 entry = NULL;
909 node = rb_next(node);
910 if (!node)
911 break;
912 }
913out:
914 if (entry)
915 atomic_inc(&entry->refs);
916 spin_unlock_irq(&tree->lock);
917 return entry;
918}
919
920bool btrfs_have_ordered_extents_in_range(struct inode *inode,
921 u64 file_offset,
922 u64 len)
923{
924 struct btrfs_ordered_extent *oe;
925
926 oe = btrfs_lookup_ordered_range(inode, file_offset, len);
927 if (oe) {
928 btrfs_put_ordered_extent(oe);
929 return true;
930 }
931 return false;
932}
933
934/*
935 * lookup and return any extent before 'file_offset'. NULL is returned
936 * if none is found
937 */
938struct btrfs_ordered_extent *
939btrfs_lookup_first_ordered_extent(struct inode *inode, u64 file_offset)
940{
941 struct btrfs_ordered_inode_tree *tree;
942 struct rb_node *node;
943 struct btrfs_ordered_extent *entry = NULL;
944
945 tree = &BTRFS_I(inode)->ordered_tree;
946 spin_lock_irq(&tree->lock);
947 node = tree_search(tree, file_offset);
948 if (!node)
949 goto out;
950
951 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
952 atomic_inc(&entry->refs);
953out:
954 spin_unlock_irq(&tree->lock);
955 return entry;
956}
957
958/*
959 * After an extent is done, call this to conditionally update the on disk
960 * i_size. i_size is updated to cover any fully written part of the file.
961 */
962int btrfs_ordered_update_i_size(struct inode *inode, u64 offset,
963 struct btrfs_ordered_extent *ordered)
964{
965 struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
966 u64 disk_i_size;
967 u64 new_i_size;
968 u64 i_size = i_size_read(inode);
969 struct rb_node *node;
970 struct rb_node *prev = NULL;
971 struct btrfs_ordered_extent *test;
972 int ret = 1;
973 u64 orig_offset = offset;
974
975 spin_lock_irq(&tree->lock);
976 if (ordered) {
977 offset = entry_end(ordered);
978 if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags))
979 offset = min(offset,
980 ordered->file_offset +
981 ordered->truncated_len);
982 } else {
983 offset = ALIGN(offset, btrfs_inode_sectorsize(inode));
984 }
985 disk_i_size = BTRFS_I(inode)->disk_i_size;
986
987 /* truncate file */
988 if (disk_i_size > i_size) {
989 BTRFS_I(inode)->disk_i_size = orig_offset;
990 ret = 0;
991 goto out;
992 }
993
994 /*
995 * if the disk i_size is already at the inode->i_size, or
996 * this ordered extent is inside the disk i_size, we're done
997 */
998 if (disk_i_size == i_size)
999 goto out;
1000
1001 /*
1002 * We still need to update disk_i_size if outstanding_isize is greater
1003 * than disk_i_size.
1004 */
1005 if (offset <= disk_i_size &&
1006 (!ordered || ordered->outstanding_isize <= disk_i_size))
1007 goto out;
1008
1009 /*
1010 * walk backward from this ordered extent to disk_i_size.
1011 * if we find an ordered extent then we can't update disk i_size
1012 * yet
1013 */
1014 if (ordered) {
1015 node = rb_prev(&ordered->rb_node);
1016 } else {
1017 prev = tree_search(tree, offset);
1018 /*
1019 * we insert file extents without involving ordered struct,
1020 * so there should be no ordered struct cover this offset
1021 */
1022 if (prev) {
1023 test = rb_entry(prev, struct btrfs_ordered_extent,
1024 rb_node);
1025 BUG_ON(offset_in_entry(test, offset));
1026 }
1027 node = prev;
1028 }
1029 for (; node; node = rb_prev(node)) {
1030 test = rb_entry(node, struct btrfs_ordered_extent, rb_node);
1031
1032 /* We treat this entry as if it doesn't exist */
1033 if (test_bit(BTRFS_ORDERED_UPDATED_ISIZE, &test->flags))
1034 continue;
1035 if (test->file_offset + test->len <= disk_i_size)
1036 break;
1037 if (test->file_offset >= i_size)
1038 break;
1039 if (entry_end(test) > disk_i_size) {
1040 /*
1041 * we don't update disk_i_size now, so record this
1042 * undealt i_size. Or we will not know the real
1043 * i_size.
1044 */
1045 if (test->outstanding_isize < offset)
1046 test->outstanding_isize = offset;
1047 if (ordered &&
1048 ordered->outstanding_isize >
1049 test->outstanding_isize)
1050 test->outstanding_isize =
1051 ordered->outstanding_isize;
1052 goto out;
1053 }
1054 }
1055 new_i_size = min_t(u64, offset, i_size);
1056
1057 /*
1058 * Some ordered extents may completed before the current one, and
1059 * we hold the real i_size in ->outstanding_isize.
1060 */
1061 if (ordered && ordered->outstanding_isize > new_i_size)
1062 new_i_size = min_t(u64, ordered->outstanding_isize, i_size);
1063 BTRFS_I(inode)->disk_i_size = new_i_size;
1064 ret = 0;
1065out:
1066 /*
1067 * We need to do this because we can't remove ordered extents until
1068 * after the i_disk_size has been updated and then the inode has been
1069 * updated to reflect the change, so we need to tell anybody who finds
1070 * this ordered extent that we've already done all the real work, we
1071 * just haven't completed all the other work.
1072 */
1073 if (ordered)
1074 set_bit(BTRFS_ORDERED_UPDATED_ISIZE, &ordered->flags);
1075 spin_unlock_irq(&tree->lock);
1076 return ret;
1077}
1078
1079/*
1080 * search the ordered extents for one corresponding to 'offset' and
1081 * try to find a checksum. This is used because we allow pages to
1082 * be reclaimed before their checksum is actually put into the btree
1083 */
1084int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
1085 u32 *sum, int len)
1086{
1087 struct btrfs_ordered_sum *ordered_sum;
1088 struct btrfs_ordered_extent *ordered;
1089 struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
1090 unsigned long num_sectors;
1091 unsigned long i;
1092 u32 sectorsize = btrfs_inode_sectorsize(inode);
1093 int index = 0;
1094
1095 ordered = btrfs_lookup_ordered_extent(inode, offset);
1096 if (!ordered)
1097 return 0;
1098
1099 spin_lock_irq(&tree->lock);
1100 list_for_each_entry_reverse(ordered_sum, &ordered->list, list) {
1101 if (disk_bytenr >= ordered_sum->bytenr &&
1102 disk_bytenr < ordered_sum->bytenr + ordered_sum->len) {
1103 i = (disk_bytenr - ordered_sum->bytenr) >>
1104 inode->i_sb->s_blocksize_bits;
1105 num_sectors = ordered_sum->len >>
1106 inode->i_sb->s_blocksize_bits;
1107 num_sectors = min_t(int, len - index, num_sectors - i);
1108 memcpy(sum + index, ordered_sum->sums + i,
1109 num_sectors);
1110
1111 index += (int)num_sectors;
1112 if (index == len)
1113 goto out;
1114 disk_bytenr += num_sectors * sectorsize;
1115 }
1116 }
1117out:
1118 spin_unlock_irq(&tree->lock);
1119 btrfs_put_ordered_extent(ordered);
1120 return index;
1121}
1122
1123int __init ordered_data_init(void)
1124{
1125 btrfs_ordered_extent_cache = kmem_cache_create("btrfs_ordered_extent",
1126 sizeof(struct btrfs_ordered_extent), 0,
1127 SLAB_MEM_SPREAD,
1128 NULL);
1129 if (!btrfs_ordered_extent_cache)
1130 return -ENOMEM;
1131
1132 return 0;
1133}
1134
1135void ordered_data_exit(void)
1136{
1137 kmem_cache_destroy(btrfs_ordered_extent_cache);
1138}