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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 "super.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 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 = 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 = BTRFS_I(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 (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 u64 num_bytes, u64 ram_bytes, u64 disk_bytenr,
268 u64 disk_num_bytes, u64 offset, unsigned long flags,
269 int compress_type)
270{
271 struct btrfs_ordered_extent *entry;
272
273 ASSERT((flags & ~BTRFS_ORDERED_TYPE_FLAGS) == 0);
274
275 entry = alloc_ordered_extent(inode, file_offset, num_bytes, ram_bytes,
276 disk_bytenr, disk_num_bytes, offset, flags,
277 compress_type);
278 if (!IS_ERR(entry))
279 insert_ordered_extent(entry);
280 return entry;
281}
282
283/*
284 * Add a struct btrfs_ordered_sum into the list of checksums to be inserted
285 * when an ordered extent is finished. If the list covers more than one
286 * ordered extent, it is split across multiples.
287 */
288void btrfs_add_ordered_sum(struct btrfs_ordered_extent *entry,
289 struct btrfs_ordered_sum *sum)
290{
291 struct btrfs_inode *inode = BTRFS_I(entry->inode);
292
293 spin_lock_irq(&inode->ordered_tree_lock);
294 list_add_tail(&sum->list, &entry->list);
295 spin_unlock_irq(&inode->ordered_tree_lock);
296}
297
298static void finish_ordered_fn(struct btrfs_work *work)
299{
300 struct btrfs_ordered_extent *ordered_extent;
301
302 ordered_extent = container_of(work, struct btrfs_ordered_extent, work);
303 btrfs_finish_ordered_io(ordered_extent);
304}
305
306static bool can_finish_ordered_extent(struct btrfs_ordered_extent *ordered,
307 struct page *page, u64 file_offset,
308 u64 len, bool uptodate)
309{
310 struct btrfs_inode *inode = BTRFS_I(ordered->inode);
311 struct btrfs_fs_info *fs_info = inode->root->fs_info;
312
313 lockdep_assert_held(&inode->ordered_tree_lock);
314
315 if (page) {
316 ASSERT(page->mapping);
317 ASSERT(page_offset(page) <= file_offset);
318 ASSERT(file_offset + len <= page_offset(page) + PAGE_SIZE);
319
320 /*
321 * Ordered (Private2) bit indicates whether we still have
322 * pending io unfinished for the ordered extent.
323 *
324 * If there's no such bit, we need to skip to next range.
325 */
326 if (!btrfs_folio_test_ordered(fs_info, page_folio(page),
327 file_offset, len))
328 return false;
329 btrfs_folio_clear_ordered(fs_info, page_folio(page), file_offset, len);
330 }
331
332 /* Now we're fine to update the accounting. */
333 if (WARN_ON_ONCE(len > ordered->bytes_left)) {
334 btrfs_crit(fs_info,
335"bad ordered extent accounting, root=%llu ino=%llu OE offset=%llu OE len=%llu to_dec=%llu left=%llu",
336 inode->root->root_key.objectid, btrfs_ino(inode),
337 ordered->file_offset, ordered->num_bytes,
338 len, ordered->bytes_left);
339 ordered->bytes_left = 0;
340 } else {
341 ordered->bytes_left -= len;
342 }
343
344 if (!uptodate)
345 set_bit(BTRFS_ORDERED_IOERR, &ordered->flags);
346
347 if (ordered->bytes_left)
348 return false;
349
350 /*
351 * All the IO of the ordered extent is finished, we need to queue
352 * the finish_func to be executed.
353 */
354 set_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags);
355 cond_wake_up(&ordered->wait);
356 refcount_inc(&ordered->refs);
357 trace_btrfs_ordered_extent_mark_finished(inode, ordered);
358 return true;
359}
360
361static void btrfs_queue_ordered_fn(struct btrfs_ordered_extent *ordered)
362{
363 struct btrfs_inode *inode = BTRFS_I(ordered->inode);
364 struct btrfs_fs_info *fs_info = inode->root->fs_info;
365 struct btrfs_workqueue *wq = btrfs_is_free_space_inode(inode) ?
366 fs_info->endio_freespace_worker : fs_info->endio_write_workers;
367
368 btrfs_init_work(&ordered->work, finish_ordered_fn, NULL);
369 btrfs_queue_work(wq, &ordered->work);
370}
371
372bool btrfs_finish_ordered_extent(struct btrfs_ordered_extent *ordered,
373 struct page *page, u64 file_offset, u64 len,
374 bool uptodate)
375{
376 struct btrfs_inode *inode = BTRFS_I(ordered->inode);
377 unsigned long flags;
378 bool ret;
379
380 trace_btrfs_finish_ordered_extent(inode, file_offset, len, uptodate);
381
382 spin_lock_irqsave(&inode->ordered_tree_lock, flags);
383 ret = can_finish_ordered_extent(ordered, page, file_offset, len, uptodate);
384 spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
385
386 if (ret)
387 btrfs_queue_ordered_fn(ordered);
388 return ret;
389}
390
391/*
392 * Mark all ordered extents io inside the specified range finished.
393 *
394 * @page: The involved page for the operation.
395 * For uncompressed buffered IO, the page status also needs to be
396 * updated to indicate whether the pending ordered io is finished.
397 * Can be NULL for direct IO and compressed write.
398 * For these cases, callers are ensured they won't execute the
399 * endio function twice.
400 *
401 * This function is called for endio, thus the range must have ordered
402 * extent(s) covering it.
403 */
404void btrfs_mark_ordered_io_finished(struct btrfs_inode *inode,
405 struct page *page, u64 file_offset,
406 u64 num_bytes, bool uptodate)
407{
408 struct rb_node *node;
409 struct btrfs_ordered_extent *entry = NULL;
410 unsigned long flags;
411 u64 cur = file_offset;
412
413 trace_btrfs_writepage_end_io_hook(inode, file_offset,
414 file_offset + num_bytes - 1,
415 uptodate);
416
417 spin_lock_irqsave(&inode->ordered_tree_lock, flags);
418 while (cur < file_offset + num_bytes) {
419 u64 entry_end;
420 u64 end;
421 u32 len;
422
423 node = ordered_tree_search(inode, cur);
424 /* No ordered extents at all */
425 if (!node)
426 break;
427
428 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
429 entry_end = entry->file_offset + entry->num_bytes;
430 /*
431 * |<-- OE --->| |
432 * cur
433 * Go to next OE.
434 */
435 if (cur >= entry_end) {
436 node = rb_next(node);
437 /* No more ordered extents, exit */
438 if (!node)
439 break;
440 entry = rb_entry(node, struct btrfs_ordered_extent,
441 rb_node);
442
443 /* Go to next ordered extent and continue */
444 cur = entry->file_offset;
445 continue;
446 }
447 /*
448 * | |<--- OE --->|
449 * cur
450 * Go to the start of OE.
451 */
452 if (cur < entry->file_offset) {
453 cur = entry->file_offset;
454 continue;
455 }
456
457 /*
458 * Now we are definitely inside one ordered extent.
459 *
460 * |<--- OE --->|
461 * |
462 * cur
463 */
464 end = min(entry->file_offset + entry->num_bytes,
465 file_offset + num_bytes) - 1;
466 ASSERT(end + 1 - cur < U32_MAX);
467 len = end + 1 - cur;
468
469 if (can_finish_ordered_extent(entry, page, cur, len, uptodate)) {
470 spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
471 btrfs_queue_ordered_fn(entry);
472 spin_lock_irqsave(&inode->ordered_tree_lock, flags);
473 }
474 cur += len;
475 }
476 spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
477}
478
479/*
480 * Finish IO for one ordered extent across a given range. The range can only
481 * contain one ordered extent.
482 *
483 * @cached: The cached ordered extent. If not NULL, we can skip the tree
484 * search and use the ordered extent directly.
485 * Will be also used to store the finished ordered extent.
486 * @file_offset: File offset for the finished IO
487 * @io_size: Length of the finish IO range
488 *
489 * Return true if the ordered extent is finished in the range, and update
490 * @cached.
491 * Return false otherwise.
492 *
493 * NOTE: The range can NOT cross multiple ordered extents.
494 * Thus caller should ensure the range doesn't cross ordered extents.
495 */
496bool btrfs_dec_test_ordered_pending(struct btrfs_inode *inode,
497 struct btrfs_ordered_extent **cached,
498 u64 file_offset, u64 io_size)
499{
500 struct rb_node *node;
501 struct btrfs_ordered_extent *entry = NULL;
502 unsigned long flags;
503 bool finished = false;
504
505 spin_lock_irqsave(&inode->ordered_tree_lock, flags);
506 if (cached && *cached) {
507 entry = *cached;
508 goto have_entry;
509 }
510
511 node = ordered_tree_search(inode, file_offset);
512 if (!node)
513 goto out;
514
515 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
516have_entry:
517 if (!in_range(file_offset, entry->file_offset, entry->num_bytes))
518 goto out;
519
520 if (io_size > entry->bytes_left)
521 btrfs_crit(inode->root->fs_info,
522 "bad ordered accounting left %llu size %llu",
523 entry->bytes_left, io_size);
524
525 entry->bytes_left -= io_size;
526
527 if (entry->bytes_left == 0) {
528 /*
529 * Ensure only one caller can set the flag and finished_ret
530 * accordingly
531 */
532 finished = !test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
533 /* test_and_set_bit implies a barrier */
534 cond_wake_up_nomb(&entry->wait);
535 }
536out:
537 if (finished && cached && entry) {
538 *cached = entry;
539 refcount_inc(&entry->refs);
540 trace_btrfs_ordered_extent_dec_test_pending(inode, entry);
541 }
542 spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
543 return finished;
544}
545
546/*
547 * used to drop a reference on an ordered extent. This will free
548 * the extent if the last reference is dropped
549 */
550void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
551{
552 struct list_head *cur;
553 struct btrfs_ordered_sum *sum;
554
555 trace_btrfs_ordered_extent_put(BTRFS_I(entry->inode), entry);
556
557 if (refcount_dec_and_test(&entry->refs)) {
558 ASSERT(list_empty(&entry->root_extent_list));
559 ASSERT(list_empty(&entry->log_list));
560 ASSERT(RB_EMPTY_NODE(&entry->rb_node));
561 if (entry->inode)
562 btrfs_add_delayed_iput(BTRFS_I(entry->inode));
563 while (!list_empty(&entry->list)) {
564 cur = entry->list.next;
565 sum = list_entry(cur, struct btrfs_ordered_sum, list);
566 list_del(&sum->list);
567 kvfree(sum);
568 }
569 kmem_cache_free(btrfs_ordered_extent_cache, entry);
570 }
571}
572
573/*
574 * remove an ordered extent from the tree. No references are dropped
575 * and waiters are woken up.
576 */
577void btrfs_remove_ordered_extent(struct btrfs_inode *btrfs_inode,
578 struct btrfs_ordered_extent *entry)
579{
580 struct btrfs_root *root = btrfs_inode->root;
581 struct btrfs_fs_info *fs_info = root->fs_info;
582 struct rb_node *node;
583 bool pending;
584 bool freespace_inode;
585
586 /*
587 * If this is a free space inode the thread has not acquired the ordered
588 * extents lockdep map.
589 */
590 freespace_inode = btrfs_is_free_space_inode(btrfs_inode);
591
592 btrfs_lockdep_acquire(fs_info, btrfs_trans_pending_ordered);
593 /* This is paired with btrfs_alloc_ordered_extent. */
594 spin_lock(&btrfs_inode->lock);
595 btrfs_mod_outstanding_extents(btrfs_inode, -1);
596 spin_unlock(&btrfs_inode->lock);
597 if (root != fs_info->tree_root) {
598 u64 release;
599
600 if (test_bit(BTRFS_ORDERED_ENCODED, &entry->flags))
601 release = entry->disk_num_bytes;
602 else
603 release = entry->num_bytes;
604 btrfs_delalloc_release_metadata(btrfs_inode, release,
605 test_bit(BTRFS_ORDERED_IOERR,
606 &entry->flags));
607 }
608
609 percpu_counter_add_batch(&fs_info->ordered_bytes, -entry->num_bytes,
610 fs_info->delalloc_batch);
611
612 spin_lock_irq(&btrfs_inode->ordered_tree_lock);
613 node = &entry->rb_node;
614 rb_erase(node, &btrfs_inode->ordered_tree);
615 RB_CLEAR_NODE(node);
616 if (btrfs_inode->ordered_tree_last == node)
617 btrfs_inode->ordered_tree_last = NULL;
618 set_bit(BTRFS_ORDERED_COMPLETE, &entry->flags);
619 pending = test_and_clear_bit(BTRFS_ORDERED_PENDING, &entry->flags);
620 spin_unlock_irq(&btrfs_inode->ordered_tree_lock);
621
622 /*
623 * The current running transaction is waiting on us, we need to let it
624 * know that we're complete and wake it up.
625 */
626 if (pending) {
627 struct btrfs_transaction *trans;
628
629 /*
630 * The checks for trans are just a formality, it should be set,
631 * but if it isn't we don't want to deref/assert under the spin
632 * lock, so be nice and check if trans is set, but ASSERT() so
633 * if it isn't set a developer will notice.
634 */
635 spin_lock(&fs_info->trans_lock);
636 trans = fs_info->running_transaction;
637 if (trans)
638 refcount_inc(&trans->use_count);
639 spin_unlock(&fs_info->trans_lock);
640
641 ASSERT(trans || BTRFS_FS_ERROR(fs_info));
642 if (trans) {
643 if (atomic_dec_and_test(&trans->pending_ordered))
644 wake_up(&trans->pending_wait);
645 btrfs_put_transaction(trans);
646 }
647 }
648
649 btrfs_lockdep_release(fs_info, btrfs_trans_pending_ordered);
650
651 spin_lock(&root->ordered_extent_lock);
652 list_del_init(&entry->root_extent_list);
653 root->nr_ordered_extents--;
654
655 trace_btrfs_ordered_extent_remove(btrfs_inode, entry);
656
657 if (!root->nr_ordered_extents) {
658 spin_lock(&fs_info->ordered_root_lock);
659 BUG_ON(list_empty(&root->ordered_root));
660 list_del_init(&root->ordered_root);
661 spin_unlock(&fs_info->ordered_root_lock);
662 }
663 spin_unlock(&root->ordered_extent_lock);
664 wake_up(&entry->wait);
665 if (!freespace_inode)
666 btrfs_lockdep_release(fs_info, btrfs_ordered_extent);
667}
668
669static void btrfs_run_ordered_extent_work(struct btrfs_work *work)
670{
671 struct btrfs_ordered_extent *ordered;
672
673 ordered = container_of(work, struct btrfs_ordered_extent, flush_work);
674 btrfs_start_ordered_extent(ordered);
675 complete(&ordered->completion);
676}
677
678/*
679 * wait for all the ordered extents in a root. This is done when balancing
680 * space between drives.
681 */
682u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,
683 const u64 range_start, const u64 range_len)
684{
685 struct btrfs_fs_info *fs_info = root->fs_info;
686 LIST_HEAD(splice);
687 LIST_HEAD(skipped);
688 LIST_HEAD(works);
689 struct btrfs_ordered_extent *ordered, *next;
690 u64 count = 0;
691 const u64 range_end = range_start + range_len;
692
693 mutex_lock(&root->ordered_extent_mutex);
694 spin_lock(&root->ordered_extent_lock);
695 list_splice_init(&root->ordered_extents, &splice);
696 while (!list_empty(&splice) && nr) {
697 ordered = list_first_entry(&splice, struct btrfs_ordered_extent,
698 root_extent_list);
699
700 if (range_end <= ordered->disk_bytenr ||
701 ordered->disk_bytenr + ordered->disk_num_bytes <= range_start) {
702 list_move_tail(&ordered->root_extent_list, &skipped);
703 cond_resched_lock(&root->ordered_extent_lock);
704 continue;
705 }
706
707 list_move_tail(&ordered->root_extent_list,
708 &root->ordered_extents);
709 refcount_inc(&ordered->refs);
710 spin_unlock(&root->ordered_extent_lock);
711
712 btrfs_init_work(&ordered->flush_work,
713 btrfs_run_ordered_extent_work, NULL);
714 list_add_tail(&ordered->work_list, &works);
715 btrfs_queue_work(fs_info->flush_workers, &ordered->flush_work);
716
717 cond_resched();
718 spin_lock(&root->ordered_extent_lock);
719 if (nr != U64_MAX)
720 nr--;
721 count++;
722 }
723 list_splice_tail(&skipped, &root->ordered_extents);
724 list_splice_tail(&splice, &root->ordered_extents);
725 spin_unlock(&root->ordered_extent_lock);
726
727 list_for_each_entry_safe(ordered, next, &works, work_list) {
728 list_del_init(&ordered->work_list);
729 wait_for_completion(&ordered->completion);
730 btrfs_put_ordered_extent(ordered);
731 cond_resched();
732 }
733 mutex_unlock(&root->ordered_extent_mutex);
734
735 return count;
736}
737
738void btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,
739 const u64 range_start, const u64 range_len)
740{
741 struct btrfs_root *root;
742 LIST_HEAD(splice);
743 u64 done;
744
745 mutex_lock(&fs_info->ordered_operations_mutex);
746 spin_lock(&fs_info->ordered_root_lock);
747 list_splice_init(&fs_info->ordered_roots, &splice);
748 while (!list_empty(&splice) && nr) {
749 root = list_first_entry(&splice, struct btrfs_root,
750 ordered_root);
751 root = btrfs_grab_root(root);
752 BUG_ON(!root);
753 list_move_tail(&root->ordered_root,
754 &fs_info->ordered_roots);
755 spin_unlock(&fs_info->ordered_root_lock);
756
757 done = btrfs_wait_ordered_extents(root, nr,
758 range_start, range_len);
759 btrfs_put_root(root);
760
761 spin_lock(&fs_info->ordered_root_lock);
762 if (nr != U64_MAX) {
763 nr -= done;
764 }
765 }
766 list_splice_tail(&splice, &fs_info->ordered_roots);
767 spin_unlock(&fs_info->ordered_root_lock);
768 mutex_unlock(&fs_info->ordered_operations_mutex);
769}
770
771/*
772 * Start IO and wait for a given ordered extent to finish.
773 *
774 * Wait on page writeback for all the pages in the extent and the IO completion
775 * code to insert metadata into the btree corresponding to the extent.
776 */
777void btrfs_start_ordered_extent(struct btrfs_ordered_extent *entry)
778{
779 u64 start = entry->file_offset;
780 u64 end = start + entry->num_bytes - 1;
781 struct btrfs_inode *inode = BTRFS_I(entry->inode);
782 bool freespace_inode;
783
784 trace_btrfs_ordered_extent_start(inode, entry);
785
786 /*
787 * If this is a free space inode do not take the ordered extents lockdep
788 * map.
789 */
790 freespace_inode = btrfs_is_free_space_inode(inode);
791
792 /*
793 * pages in the range can be dirty, clean or writeback. We
794 * start IO on any dirty ones so the wait doesn't stall waiting
795 * for the flusher thread to find them
796 */
797 if (!test_bit(BTRFS_ORDERED_DIRECT, &entry->flags))
798 filemap_fdatawrite_range(inode->vfs_inode.i_mapping, start, end);
799
800 if (!freespace_inode)
801 btrfs_might_wait_for_event(inode->root->fs_info, btrfs_ordered_extent);
802 wait_event(entry->wait, test_bit(BTRFS_ORDERED_COMPLETE, &entry->flags));
803}
804
805/*
806 * Used to wait on ordered extents across a large range of bytes.
807 */
808int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len)
809{
810 int ret = 0;
811 int ret_wb = 0;
812 u64 end;
813 u64 orig_end;
814 struct btrfs_ordered_extent *ordered;
815
816 if (start + len < start) {
817 orig_end = OFFSET_MAX;
818 } else {
819 orig_end = start + len - 1;
820 if (orig_end > OFFSET_MAX)
821 orig_end = OFFSET_MAX;
822 }
823
824 /* start IO across the range first to instantiate any delalloc
825 * extents
826 */
827 ret = btrfs_fdatawrite_range(inode, start, orig_end);
828 if (ret)
829 return ret;
830
831 /*
832 * If we have a writeback error don't return immediately. Wait first
833 * for any ordered extents that haven't completed yet. This is to make
834 * sure no one can dirty the same page ranges and call writepages()
835 * before the ordered extents complete - to avoid failures (-EEXIST)
836 * when adding the new ordered extents to the ordered tree.
837 */
838 ret_wb = filemap_fdatawait_range(inode->i_mapping, start, orig_end);
839
840 end = orig_end;
841 while (1) {
842 ordered = btrfs_lookup_first_ordered_extent(BTRFS_I(inode), end);
843 if (!ordered)
844 break;
845 if (ordered->file_offset > orig_end) {
846 btrfs_put_ordered_extent(ordered);
847 break;
848 }
849 if (ordered->file_offset + ordered->num_bytes <= start) {
850 btrfs_put_ordered_extent(ordered);
851 break;
852 }
853 btrfs_start_ordered_extent(ordered);
854 end = ordered->file_offset;
855 /*
856 * If the ordered extent had an error save the error but don't
857 * exit without waiting first for all other ordered extents in
858 * the range to complete.
859 */
860 if (test_bit(BTRFS_ORDERED_IOERR, &ordered->flags))
861 ret = -EIO;
862 btrfs_put_ordered_extent(ordered);
863 if (end == 0 || end == start)
864 break;
865 end--;
866 }
867 return ret_wb ? ret_wb : ret;
868}
869
870/*
871 * find an ordered extent corresponding to file_offset. return NULL if
872 * nothing is found, otherwise take a reference on the extent and return it
873 */
874struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct btrfs_inode *inode,
875 u64 file_offset)
876{
877 struct rb_node *node;
878 struct btrfs_ordered_extent *entry = NULL;
879 unsigned long flags;
880
881 spin_lock_irqsave(&inode->ordered_tree_lock, flags);
882 node = ordered_tree_search(inode, file_offset);
883 if (!node)
884 goto out;
885
886 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
887 if (!in_range(file_offset, entry->file_offset, entry->num_bytes))
888 entry = NULL;
889 if (entry) {
890 refcount_inc(&entry->refs);
891 trace_btrfs_ordered_extent_lookup(inode, entry);
892 }
893out:
894 spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
895 return entry;
896}
897
898/* Since the DIO code tries to lock a wide area we need to look for any ordered
899 * extents that exist in the range, rather than just the start of the range.
900 */
901struct btrfs_ordered_extent *btrfs_lookup_ordered_range(
902 struct btrfs_inode *inode, u64 file_offset, u64 len)
903{
904 struct rb_node *node;
905 struct btrfs_ordered_extent *entry = NULL;
906
907 spin_lock_irq(&inode->ordered_tree_lock);
908 node = ordered_tree_search(inode, file_offset);
909 if (!node) {
910 node = ordered_tree_search(inode, file_offset + len);
911 if (!node)
912 goto out;
913 }
914
915 while (1) {
916 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
917 if (range_overlaps(entry, file_offset, len))
918 break;
919
920 if (entry->file_offset >= file_offset + len) {
921 entry = NULL;
922 break;
923 }
924 entry = NULL;
925 node = rb_next(node);
926 if (!node)
927 break;
928 }
929out:
930 if (entry) {
931 refcount_inc(&entry->refs);
932 trace_btrfs_ordered_extent_lookup_range(inode, entry);
933 }
934 spin_unlock_irq(&inode->ordered_tree_lock);
935 return entry;
936}
937
938/*
939 * Adds all ordered extents to the given list. The list ends up sorted by the
940 * file_offset of the ordered extents.
941 */
942void btrfs_get_ordered_extents_for_logging(struct btrfs_inode *inode,
943 struct list_head *list)
944{
945 struct rb_node *n;
946
947 ASSERT(inode_is_locked(&inode->vfs_inode));
948
949 spin_lock_irq(&inode->ordered_tree_lock);
950 for (n = rb_first(&inode->ordered_tree); n; n = rb_next(n)) {
951 struct btrfs_ordered_extent *ordered;
952
953 ordered = rb_entry(n, struct btrfs_ordered_extent, rb_node);
954
955 if (test_bit(BTRFS_ORDERED_LOGGED, &ordered->flags))
956 continue;
957
958 ASSERT(list_empty(&ordered->log_list));
959 list_add_tail(&ordered->log_list, list);
960 refcount_inc(&ordered->refs);
961 trace_btrfs_ordered_extent_lookup_for_logging(inode, ordered);
962 }
963 spin_unlock_irq(&inode->ordered_tree_lock);
964}
965
966/*
967 * lookup and return any extent before 'file_offset'. NULL is returned
968 * if none is found
969 */
970struct btrfs_ordered_extent *
971btrfs_lookup_first_ordered_extent(struct btrfs_inode *inode, u64 file_offset)
972{
973 struct rb_node *node;
974 struct btrfs_ordered_extent *entry = NULL;
975
976 spin_lock_irq(&inode->ordered_tree_lock);
977 node = ordered_tree_search(inode, file_offset);
978 if (!node)
979 goto out;
980
981 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
982 refcount_inc(&entry->refs);
983 trace_btrfs_ordered_extent_lookup_first(inode, entry);
984out:
985 spin_unlock_irq(&inode->ordered_tree_lock);
986 return entry;
987}
988
989/*
990 * Lookup the first ordered extent that overlaps the range
991 * [@file_offset, @file_offset + @len).
992 *
993 * The difference between this and btrfs_lookup_first_ordered_extent() is
994 * that this one won't return any ordered extent that does not overlap the range.
995 * And the difference against btrfs_lookup_ordered_extent() is, this function
996 * ensures the first ordered extent gets returned.
997 */
998struct btrfs_ordered_extent *btrfs_lookup_first_ordered_range(
999 struct btrfs_inode *inode, u64 file_offset, u64 len)
1000{
1001 struct rb_node *node;
1002 struct rb_node *cur;
1003 struct rb_node *prev;
1004 struct rb_node *next;
1005 struct btrfs_ordered_extent *entry = NULL;
1006
1007 spin_lock_irq(&inode->ordered_tree_lock);
1008 node = inode->ordered_tree.rb_node;
1009 /*
1010 * Here we don't want to use tree_search() which will use tree->last
1011 * and screw up the search order.
1012 * And __tree_search() can't return the adjacent ordered extents
1013 * either, thus here we do our own search.
1014 */
1015 while (node) {
1016 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
1017
1018 if (file_offset < entry->file_offset) {
1019 node = node->rb_left;
1020 } else if (file_offset >= entry_end(entry)) {
1021 node = node->rb_right;
1022 } else {
1023 /*
1024 * Direct hit, got an ordered extent that starts at
1025 * @file_offset
1026 */
1027 goto out;
1028 }
1029 }
1030 if (!entry) {
1031 /* Empty tree */
1032 goto out;
1033 }
1034
1035 cur = &entry->rb_node;
1036 /* We got an entry around @file_offset, check adjacent entries */
1037 if (entry->file_offset < file_offset) {
1038 prev = cur;
1039 next = rb_next(cur);
1040 } else {
1041 prev = rb_prev(cur);
1042 next = cur;
1043 }
1044 if (prev) {
1045 entry = rb_entry(prev, struct btrfs_ordered_extent, rb_node);
1046 if (range_overlaps(entry, file_offset, len))
1047 goto out;
1048 }
1049 if (next) {
1050 entry = rb_entry(next, struct btrfs_ordered_extent, rb_node);
1051 if (range_overlaps(entry, file_offset, len))
1052 goto out;
1053 }
1054 /* No ordered extent in the range */
1055 entry = NULL;
1056out:
1057 if (entry) {
1058 refcount_inc(&entry->refs);
1059 trace_btrfs_ordered_extent_lookup_first_range(inode, entry);
1060 }
1061
1062 spin_unlock_irq(&inode->ordered_tree_lock);
1063 return entry;
1064}
1065
1066/*
1067 * Lock the passed range and ensures all pending ordered extents in it are run
1068 * to completion.
1069 *
1070 * @inode: Inode whose ordered tree is to be searched
1071 * @start: Beginning of range to flush
1072 * @end: Last byte of range to lock
1073 * @cached_state: If passed, will return the extent state responsible for the
1074 * locked range. It's the caller's responsibility to free the
1075 * cached state.
1076 *
1077 * Always return with the given range locked, ensuring after it's called no
1078 * order extent can be pending.
1079 */
1080void btrfs_lock_and_flush_ordered_range(struct btrfs_inode *inode, u64 start,
1081 u64 end,
1082 struct extent_state **cached_state)
1083{
1084 struct btrfs_ordered_extent *ordered;
1085 struct extent_state *cache = NULL;
1086 struct extent_state **cachedp = &cache;
1087
1088 if (cached_state)
1089 cachedp = cached_state;
1090
1091 while (1) {
1092 lock_extent(&inode->io_tree, start, end, cachedp);
1093 ordered = btrfs_lookup_ordered_range(inode, start,
1094 end - start + 1);
1095 if (!ordered) {
1096 /*
1097 * If no external cached_state has been passed then
1098 * decrement the extra ref taken for cachedp since we
1099 * aren't exposing it outside of this function
1100 */
1101 if (!cached_state)
1102 refcount_dec(&cache->refs);
1103 break;
1104 }
1105 unlock_extent(&inode->io_tree, start, end, cachedp);
1106 btrfs_start_ordered_extent(ordered);
1107 btrfs_put_ordered_extent(ordered);
1108 }
1109}
1110
1111/*
1112 * Lock the passed range and ensure all pending ordered extents in it are run
1113 * to completion in nowait mode.
1114 *
1115 * Return true if btrfs_lock_ordered_range does not return any extents,
1116 * otherwise false.
1117 */
1118bool btrfs_try_lock_ordered_range(struct btrfs_inode *inode, u64 start, u64 end,
1119 struct extent_state **cached_state)
1120{
1121 struct btrfs_ordered_extent *ordered;
1122
1123 if (!try_lock_extent(&inode->io_tree, start, end, cached_state))
1124 return false;
1125
1126 ordered = btrfs_lookup_ordered_range(inode, start, end - start + 1);
1127 if (!ordered)
1128 return true;
1129
1130 btrfs_put_ordered_extent(ordered);
1131 unlock_extent(&inode->io_tree, start, end, cached_state);
1132
1133 return false;
1134}
1135
1136/* Split out a new ordered extent for this first @len bytes of @ordered. */
1137struct btrfs_ordered_extent *btrfs_split_ordered_extent(
1138 struct btrfs_ordered_extent *ordered, u64 len)
1139{
1140 struct btrfs_inode *inode = BTRFS_I(ordered->inode);
1141 struct btrfs_root *root = inode->root;
1142 struct btrfs_fs_info *fs_info = root->fs_info;
1143 u64 file_offset = ordered->file_offset;
1144 u64 disk_bytenr = ordered->disk_bytenr;
1145 unsigned long flags = ordered->flags;
1146 struct btrfs_ordered_sum *sum, *tmpsum;
1147 struct btrfs_ordered_extent *new;
1148 struct rb_node *node;
1149 u64 offset = 0;
1150
1151 trace_btrfs_ordered_extent_split(inode, ordered);
1152
1153 ASSERT(!(flags & (1U << BTRFS_ORDERED_COMPRESSED)));
1154
1155 /*
1156 * The entire bio must be covered by the ordered extent, but we can't
1157 * reduce the original extent to a zero length either.
1158 */
1159 if (WARN_ON_ONCE(len >= ordered->num_bytes))
1160 return ERR_PTR(-EINVAL);
1161 /* We cannot split partially completed ordered extents. */
1162 if (ordered->bytes_left) {
1163 ASSERT(!(flags & ~BTRFS_ORDERED_TYPE_FLAGS));
1164 if (WARN_ON_ONCE(ordered->bytes_left != ordered->disk_num_bytes))
1165 return ERR_PTR(-EINVAL);
1166 }
1167 /* We cannot split a compressed ordered extent. */
1168 if (WARN_ON_ONCE(ordered->disk_num_bytes != ordered->num_bytes))
1169 return ERR_PTR(-EINVAL);
1170
1171 new = alloc_ordered_extent(inode, file_offset, len, len, disk_bytenr,
1172 len, 0, flags, ordered->compress_type);
1173 if (IS_ERR(new))
1174 return new;
1175
1176 /* One ref for the tree. */
1177 refcount_inc(&new->refs);
1178
1179 spin_lock_irq(&root->ordered_extent_lock);
1180 spin_lock(&inode->ordered_tree_lock);
1181 /* Remove from tree once */
1182 node = &ordered->rb_node;
1183 rb_erase(node, &inode->ordered_tree);
1184 RB_CLEAR_NODE(node);
1185 if (inode->ordered_tree_last == node)
1186 inode->ordered_tree_last = NULL;
1187
1188 ordered->file_offset += len;
1189 ordered->disk_bytenr += len;
1190 ordered->num_bytes -= len;
1191 ordered->disk_num_bytes -= len;
1192
1193 if (test_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags)) {
1194 ASSERT(ordered->bytes_left == 0);
1195 new->bytes_left = 0;
1196 } else {
1197 ordered->bytes_left -= len;
1198 }
1199
1200 if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags)) {
1201 if (ordered->truncated_len > len) {
1202 ordered->truncated_len -= len;
1203 } else {
1204 new->truncated_len = ordered->truncated_len;
1205 ordered->truncated_len = 0;
1206 }
1207 }
1208
1209 list_for_each_entry_safe(sum, tmpsum, &ordered->list, list) {
1210 if (offset == len)
1211 break;
1212 list_move_tail(&sum->list, &new->list);
1213 offset += sum->len;
1214 }
1215
1216 /* Re-insert the node */
1217 node = tree_insert(&inode->ordered_tree, ordered->file_offset,
1218 &ordered->rb_node);
1219 if (node)
1220 btrfs_panic(fs_info, -EEXIST,
1221 "zoned: inconsistency in ordered tree at offset %llu",
1222 ordered->file_offset);
1223
1224 node = tree_insert(&inode->ordered_tree, new->file_offset, &new->rb_node);
1225 if (node)
1226 btrfs_panic(fs_info, -EEXIST,
1227 "zoned: inconsistency in ordered tree at offset %llu",
1228 new->file_offset);
1229 spin_unlock(&inode->ordered_tree_lock);
1230
1231 list_add_tail(&new->root_extent_list, &root->ordered_extents);
1232 root->nr_ordered_extents++;
1233 spin_unlock_irq(&root->ordered_extent_lock);
1234 return new;
1235}
1236
1237int __init ordered_data_init(void)
1238{
1239 btrfs_ordered_extent_cache = kmem_cache_create("btrfs_ordered_extent",
1240 sizeof(struct btrfs_ordered_extent), 0,
1241 SLAB_MEM_SPREAD,
1242 NULL);
1243 if (!btrfs_ordered_extent_cache)
1244 return -ENOMEM;
1245
1246 return 0;
1247}
1248
1249void __cold ordered_data_exit(void)
1250{
1251 kmem_cache_destroy(btrfs_ordered_extent_cache);
1252}
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, "Inconsistency in ordered tree at offset "
71 "%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_root *root = BTRFS_I(inode)->root;
190 struct btrfs_ordered_inode_tree *tree;
191 struct rb_node *node;
192 struct btrfs_ordered_extent *entry;
193
194 tree = &BTRFS_I(inode)->ordered_tree;
195 entry = kmem_cache_zalloc(btrfs_ordered_extent_cache, GFP_NOFS);
196 if (!entry)
197 return -ENOMEM;
198
199 entry->file_offset = file_offset;
200 entry->start = start;
201 entry->len = len;
202 entry->disk_len = disk_len;
203 entry->bytes_left = len;
204 entry->inode = igrab(inode);
205 entry->compress_type = compress_type;
206 entry->truncated_len = (u64)-1;
207 if (type != BTRFS_ORDERED_IO_DONE && type != BTRFS_ORDERED_COMPLETE)
208 set_bit(type, &entry->flags);
209
210 if (dio)
211 set_bit(BTRFS_ORDERED_DIRECT, &entry->flags);
212
213 /* one ref for the tree */
214 atomic_set(&entry->refs, 1);
215 init_waitqueue_head(&entry->wait);
216 INIT_LIST_HEAD(&entry->list);
217 INIT_LIST_HEAD(&entry->root_extent_list);
218 INIT_LIST_HEAD(&entry->work_list);
219 init_completion(&entry->completion);
220 INIT_LIST_HEAD(&entry->log_list);
221 INIT_LIST_HEAD(&entry->trans_list);
222
223 trace_btrfs_ordered_extent_add(inode, entry);
224
225 spin_lock_irq(&tree->lock);
226 node = tree_insert(&tree->tree, file_offset,
227 &entry->rb_node);
228 if (node)
229 ordered_data_tree_panic(inode, -EEXIST, file_offset);
230 spin_unlock_irq(&tree->lock);
231
232 spin_lock(&root->ordered_extent_lock);
233 list_add_tail(&entry->root_extent_list,
234 &root->ordered_extents);
235 root->nr_ordered_extents++;
236 if (root->nr_ordered_extents == 1) {
237 spin_lock(&root->fs_info->ordered_root_lock);
238 BUG_ON(!list_empty(&root->ordered_root));
239 list_add_tail(&root->ordered_root,
240 &root->fs_info->ordered_roots);
241 spin_unlock(&root->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_ordered_inode_tree *tree;
307 struct rb_node *node;
308 struct btrfs_ordered_extent *entry = NULL;
309 int ret;
310 unsigned long flags;
311 u64 dec_end;
312 u64 dec_start;
313 u64 to_dec;
314
315 tree = &BTRFS_I(inode)->ordered_tree;
316 spin_lock_irqsave(&tree->lock, flags);
317 node = tree_search(tree, *file_offset);
318 if (!node) {
319 ret = 1;
320 goto out;
321 }
322
323 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
324 if (!offset_in_entry(entry, *file_offset)) {
325 ret = 1;
326 goto out;
327 }
328
329 dec_start = max(*file_offset, entry->file_offset);
330 dec_end = min(*file_offset + io_size, entry->file_offset +
331 entry->len);
332 *file_offset = dec_end;
333 if (dec_start > dec_end) {
334 btrfs_crit(BTRFS_I(inode)->root->fs_info,
335 "bad ordering dec_start %llu end %llu", dec_start, dec_end);
336 }
337 to_dec = dec_end - dec_start;
338 if (to_dec > entry->bytes_left) {
339 btrfs_crit(BTRFS_I(inode)->root->fs_info,
340 "bad ordered accounting left %llu size %llu",
341 entry->bytes_left, to_dec);
342 }
343 entry->bytes_left -= to_dec;
344 if (!uptodate)
345 set_bit(BTRFS_ORDERED_IOERR, &entry->flags);
346
347 if (entry->bytes_left == 0) {
348 ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
349 /*
350 * Implicit memory barrier after test_and_set_bit
351 */
352 if (waitqueue_active(&entry->wait))
353 wake_up(&entry->wait);
354 } else {
355 ret = 1;
356 }
357out:
358 if (!ret && cached && entry) {
359 *cached = entry;
360 atomic_inc(&entry->refs);
361 }
362 spin_unlock_irqrestore(&tree->lock, flags);
363 return ret == 0;
364}
365
366/*
367 * this is used to account for finished IO across a given range
368 * of the file. The IO should not span ordered extents. If
369 * a given ordered_extent is completely done, 1 is returned, otherwise
370 * 0.
371 *
372 * test_and_set_bit on a flag in the struct btrfs_ordered_extent is used
373 * to make sure this function only returns 1 once for a given ordered extent.
374 */
375int btrfs_dec_test_ordered_pending(struct inode *inode,
376 struct btrfs_ordered_extent **cached,
377 u64 file_offset, u64 io_size, int uptodate)
378{
379 struct btrfs_ordered_inode_tree *tree;
380 struct rb_node *node;
381 struct btrfs_ordered_extent *entry = NULL;
382 unsigned long flags;
383 int ret;
384
385 tree = &BTRFS_I(inode)->ordered_tree;
386 spin_lock_irqsave(&tree->lock, flags);
387 if (cached && *cached) {
388 entry = *cached;
389 goto have_entry;
390 }
391
392 node = tree_search(tree, file_offset);
393 if (!node) {
394 ret = 1;
395 goto out;
396 }
397
398 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
399have_entry:
400 if (!offset_in_entry(entry, file_offset)) {
401 ret = 1;
402 goto out;
403 }
404
405 if (io_size > entry->bytes_left) {
406 btrfs_crit(BTRFS_I(inode)->root->fs_info,
407 "bad ordered accounting left %llu size %llu",
408 entry->bytes_left, io_size);
409 }
410 entry->bytes_left -= io_size;
411 if (!uptodate)
412 set_bit(BTRFS_ORDERED_IOERR, &entry->flags);
413
414 if (entry->bytes_left == 0) {
415 ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
416 /*
417 * Implicit memory barrier after test_and_set_bit
418 */
419 if (waitqueue_active(&entry->wait))
420 wake_up(&entry->wait);
421 } else {
422 ret = 1;
423 }
424out:
425 if (!ret && cached && entry) {
426 *cached = entry;
427 atomic_inc(&entry->refs);
428 }
429 spin_unlock_irqrestore(&tree->lock, flags);
430 return ret == 0;
431}
432
433/* Needs to either be called under a log transaction or the log_mutex */
434void btrfs_get_logged_extents(struct inode *inode,
435 struct list_head *logged_list,
436 const loff_t start,
437 const loff_t end)
438{
439 struct btrfs_ordered_inode_tree *tree;
440 struct btrfs_ordered_extent *ordered;
441 struct rb_node *n;
442 struct rb_node *prev;
443
444 tree = &BTRFS_I(inode)->ordered_tree;
445 spin_lock_irq(&tree->lock);
446 n = __tree_search(&tree->tree, end, &prev);
447 if (!n)
448 n = prev;
449 for (; n; n = rb_prev(n)) {
450 ordered = rb_entry(n, struct btrfs_ordered_extent, rb_node);
451 if (ordered->file_offset > end)
452 continue;
453 if (entry_end(ordered) <= start)
454 break;
455 if (test_and_set_bit(BTRFS_ORDERED_LOGGED, &ordered->flags))
456 continue;
457 list_add(&ordered->log_list, logged_list);
458 atomic_inc(&ordered->refs);
459 }
460 spin_unlock_irq(&tree->lock);
461}
462
463void btrfs_put_logged_extents(struct list_head *logged_list)
464{
465 struct btrfs_ordered_extent *ordered;
466
467 while (!list_empty(logged_list)) {
468 ordered = list_first_entry(logged_list,
469 struct btrfs_ordered_extent,
470 log_list);
471 list_del_init(&ordered->log_list);
472 btrfs_put_ordered_extent(ordered);
473 }
474}
475
476void btrfs_submit_logged_extents(struct list_head *logged_list,
477 struct btrfs_root *log)
478{
479 int index = log->log_transid % 2;
480
481 spin_lock_irq(&log->log_extents_lock[index]);
482 list_splice_tail(logged_list, &log->logged_list[index]);
483 spin_unlock_irq(&log->log_extents_lock[index]);
484}
485
486void btrfs_wait_logged_extents(struct btrfs_trans_handle *trans,
487 struct btrfs_root *log, u64 transid)
488{
489 struct btrfs_ordered_extent *ordered;
490 int index = transid % 2;
491
492 spin_lock_irq(&log->log_extents_lock[index]);
493 while (!list_empty(&log->logged_list[index])) {
494 struct inode *inode;
495 ordered = list_first_entry(&log->logged_list[index],
496 struct btrfs_ordered_extent,
497 log_list);
498 list_del_init(&ordered->log_list);
499 inode = ordered->inode;
500 spin_unlock_irq(&log->log_extents_lock[index]);
501
502 if (!test_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags) &&
503 !test_bit(BTRFS_ORDERED_DIRECT, &ordered->flags)) {
504 u64 start = ordered->file_offset;
505 u64 end = ordered->file_offset + ordered->len - 1;
506
507 WARN_ON(!inode);
508 filemap_fdatawrite_range(inode->i_mapping, start, end);
509 }
510 wait_event(ordered->wait, test_bit(BTRFS_ORDERED_IO_DONE,
511 &ordered->flags));
512
513 /*
514 * In order to keep us from losing our ordered extent
515 * information when committing the transaction we have to make
516 * sure that any logged extents are completed when we go to
517 * commit the transaction. To do this we simply increase the
518 * current transactions pending_ordered counter and decrement it
519 * when the ordered extent completes.
520 */
521 if (!test_bit(BTRFS_ORDERED_COMPLETE, &ordered->flags)) {
522 struct btrfs_ordered_inode_tree *tree;
523
524 tree = &BTRFS_I(inode)->ordered_tree;
525 spin_lock_irq(&tree->lock);
526 if (!test_bit(BTRFS_ORDERED_COMPLETE, &ordered->flags)) {
527 set_bit(BTRFS_ORDERED_PENDING, &ordered->flags);
528 atomic_inc(&trans->transaction->pending_ordered);
529 }
530 spin_unlock_irq(&tree->lock);
531 }
532 btrfs_put_ordered_extent(ordered);
533 spin_lock_irq(&log->log_extents_lock[index]);
534 }
535 spin_unlock_irq(&log->log_extents_lock[index]);
536}
537
538void btrfs_free_logged_extents(struct btrfs_root *log, u64 transid)
539{
540 struct btrfs_ordered_extent *ordered;
541 int index = transid % 2;
542
543 spin_lock_irq(&log->log_extents_lock[index]);
544 while (!list_empty(&log->logged_list[index])) {
545 ordered = list_first_entry(&log->logged_list[index],
546 struct btrfs_ordered_extent,
547 log_list);
548 list_del_init(&ordered->log_list);
549 spin_unlock_irq(&log->log_extents_lock[index]);
550 btrfs_put_ordered_extent(ordered);
551 spin_lock_irq(&log->log_extents_lock[index]);
552 }
553 spin_unlock_irq(&log->log_extents_lock[index]);
554}
555
556/*
557 * used to drop a reference on an ordered extent. This will free
558 * the extent if the last reference is dropped
559 */
560void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
561{
562 struct list_head *cur;
563 struct btrfs_ordered_sum *sum;
564
565 trace_btrfs_ordered_extent_put(entry->inode, entry);
566
567 if (atomic_dec_and_test(&entry->refs)) {
568 ASSERT(list_empty(&entry->log_list));
569 ASSERT(list_empty(&entry->trans_list));
570 ASSERT(list_empty(&entry->root_extent_list));
571 ASSERT(RB_EMPTY_NODE(&entry->rb_node));
572 if (entry->inode)
573 btrfs_add_delayed_iput(entry->inode);
574 while (!list_empty(&entry->list)) {
575 cur = entry->list.next;
576 sum = list_entry(cur, struct btrfs_ordered_sum, list);
577 list_del(&sum->list);
578 kfree(sum);
579 }
580 kmem_cache_free(btrfs_ordered_extent_cache, entry);
581 }
582}
583
584/*
585 * remove an ordered extent from the tree. No references are dropped
586 * and waiters are woken up.
587 */
588void btrfs_remove_ordered_extent(struct inode *inode,
589 struct btrfs_ordered_extent *entry)
590{
591 struct btrfs_ordered_inode_tree *tree;
592 struct btrfs_root *root = BTRFS_I(inode)->root;
593 struct rb_node *node;
594 bool dec_pending_ordered = false;
595
596 tree = &BTRFS_I(inode)->ordered_tree;
597 spin_lock_irq(&tree->lock);
598 node = &entry->rb_node;
599 rb_erase(node, &tree->tree);
600 RB_CLEAR_NODE(node);
601 if (tree->last == node)
602 tree->last = NULL;
603 set_bit(BTRFS_ORDERED_COMPLETE, &entry->flags);
604 if (test_and_clear_bit(BTRFS_ORDERED_PENDING, &entry->flags))
605 dec_pending_ordered = true;
606 spin_unlock_irq(&tree->lock);
607
608 /*
609 * The current running transaction is waiting on us, we need to let it
610 * know that we're complete and wake it up.
611 */
612 if (dec_pending_ordered) {
613 struct btrfs_transaction *trans;
614
615 /*
616 * The checks for trans are just a formality, it should be set,
617 * but if it isn't we don't want to deref/assert under the spin
618 * lock, so be nice and check if trans is set, but ASSERT() so
619 * if it isn't set a developer will notice.
620 */
621 spin_lock(&root->fs_info->trans_lock);
622 trans = root->fs_info->running_transaction;
623 if (trans)
624 atomic_inc(&trans->use_count);
625 spin_unlock(&root->fs_info->trans_lock);
626
627 ASSERT(trans);
628 if (trans) {
629 if (atomic_dec_and_test(&trans->pending_ordered))
630 wake_up(&trans->pending_wait);
631 btrfs_put_transaction(trans);
632 }
633 }
634
635 spin_lock(&root->ordered_extent_lock);
636 list_del_init(&entry->root_extent_list);
637 root->nr_ordered_extents--;
638
639 trace_btrfs_ordered_extent_remove(inode, entry);
640
641 if (!root->nr_ordered_extents) {
642 spin_lock(&root->fs_info->ordered_root_lock);
643 BUG_ON(list_empty(&root->ordered_root));
644 list_del_init(&root->ordered_root);
645 spin_unlock(&root->fs_info->ordered_root_lock);
646 }
647 spin_unlock(&root->ordered_extent_lock);
648 wake_up(&entry->wait);
649}
650
651static void btrfs_run_ordered_extent_work(struct btrfs_work *work)
652{
653 struct btrfs_ordered_extent *ordered;
654
655 ordered = container_of(work, struct btrfs_ordered_extent, flush_work);
656 btrfs_start_ordered_extent(ordered->inode, ordered, 1);
657 complete(&ordered->completion);
658}
659
660/*
661 * wait for all the ordered extents in a root. This is done when balancing
662 * space between drives.
663 */
664int btrfs_wait_ordered_extents(struct btrfs_root *root, int nr)
665{
666 struct list_head splice, works;
667 struct btrfs_ordered_extent *ordered, *next;
668 int count = 0;
669
670 INIT_LIST_HEAD(&splice);
671 INIT_LIST_HEAD(&works);
672
673 mutex_lock(&root->ordered_extent_mutex);
674 spin_lock(&root->ordered_extent_lock);
675 list_splice_init(&root->ordered_extents, &splice);
676 while (!list_empty(&splice) && nr) {
677 ordered = list_first_entry(&splice, struct btrfs_ordered_extent,
678 root_extent_list);
679 list_move_tail(&ordered->root_extent_list,
680 &root->ordered_extents);
681 atomic_inc(&ordered->refs);
682 spin_unlock(&root->ordered_extent_lock);
683
684 btrfs_init_work(&ordered->flush_work,
685 btrfs_flush_delalloc_helper,
686 btrfs_run_ordered_extent_work, NULL, NULL);
687 list_add_tail(&ordered->work_list, &works);
688 btrfs_queue_work(root->fs_info->flush_workers,
689 &ordered->flush_work);
690
691 cond_resched();
692 spin_lock(&root->ordered_extent_lock);
693 if (nr != -1)
694 nr--;
695 count++;
696 }
697 list_splice_tail(&splice, &root->ordered_extents);
698 spin_unlock(&root->ordered_extent_lock);
699
700 list_for_each_entry_safe(ordered, next, &works, work_list) {
701 list_del_init(&ordered->work_list);
702 wait_for_completion(&ordered->completion);
703 btrfs_put_ordered_extent(ordered);
704 cond_resched();
705 }
706 mutex_unlock(&root->ordered_extent_mutex);
707
708 return count;
709}
710
711void btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, int nr)
712{
713 struct btrfs_root *root;
714 struct list_head splice;
715 int done;
716
717 INIT_LIST_HEAD(&splice);
718
719 mutex_lock(&fs_info->ordered_operations_mutex);
720 spin_lock(&fs_info->ordered_root_lock);
721 list_splice_init(&fs_info->ordered_roots, &splice);
722 while (!list_empty(&splice) && nr) {
723 root = list_first_entry(&splice, struct btrfs_root,
724 ordered_root);
725 root = btrfs_grab_fs_root(root);
726 BUG_ON(!root);
727 list_move_tail(&root->ordered_root,
728 &fs_info->ordered_roots);
729 spin_unlock(&fs_info->ordered_root_lock);
730
731 done = btrfs_wait_ordered_extents(root, nr);
732 btrfs_put_fs_root(root);
733
734 spin_lock(&fs_info->ordered_root_lock);
735 if (nr != -1) {
736 nr -= done;
737 WARN_ON(nr < 0);
738 }
739 }
740 list_splice_tail(&splice, &fs_info->ordered_roots);
741 spin_unlock(&fs_info->ordered_root_lock);
742 mutex_unlock(&fs_info->ordered_operations_mutex);
743}
744
745/*
746 * Used to start IO or wait for a given ordered extent to finish.
747 *
748 * If wait is one, this effectively waits on page writeback for all the pages
749 * in the extent, and it waits on the io completion code to insert
750 * metadata into the btree corresponding to the extent
751 */
752void btrfs_start_ordered_extent(struct inode *inode,
753 struct btrfs_ordered_extent *entry,
754 int wait)
755{
756 u64 start = entry->file_offset;
757 u64 end = start + entry->len - 1;
758
759 trace_btrfs_ordered_extent_start(inode, entry);
760
761 /*
762 * pages in the range can be dirty, clean or writeback. We
763 * start IO on any dirty ones so the wait doesn't stall waiting
764 * for the flusher thread to find them
765 */
766 if (!test_bit(BTRFS_ORDERED_DIRECT, &entry->flags))
767 filemap_fdatawrite_range(inode->i_mapping, start, end);
768 if (wait) {
769 wait_event(entry->wait, test_bit(BTRFS_ORDERED_COMPLETE,
770 &entry->flags));
771 }
772}
773
774/*
775 * Used to wait on ordered extents across a large range of bytes.
776 */
777int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len)
778{
779 int ret = 0;
780 int ret_wb = 0;
781 u64 end;
782 u64 orig_end;
783 struct btrfs_ordered_extent *ordered;
784
785 if (start + len < start) {
786 orig_end = INT_LIMIT(loff_t);
787 } else {
788 orig_end = start + len - 1;
789 if (orig_end > INT_LIMIT(loff_t))
790 orig_end = INT_LIMIT(loff_t);
791 }
792
793 /* start IO across the range first to instantiate any delalloc
794 * extents
795 */
796 ret = btrfs_fdatawrite_range(inode, start, orig_end);
797 if (ret)
798 return ret;
799
800 /*
801 * If we have a writeback error don't return immediately. Wait first
802 * for any ordered extents that haven't completed yet. This is to make
803 * sure no one can dirty the same page ranges and call writepages()
804 * before the ordered extents complete - to avoid failures (-EEXIST)
805 * when adding the new ordered extents to the ordered tree.
806 */
807 ret_wb = filemap_fdatawait_range(inode->i_mapping, start, orig_end);
808
809 end = orig_end;
810 while (1) {
811 ordered = btrfs_lookup_first_ordered_extent(inode, end);
812 if (!ordered)
813 break;
814 if (ordered->file_offset > orig_end) {
815 btrfs_put_ordered_extent(ordered);
816 break;
817 }
818 if (ordered->file_offset + ordered->len <= start) {
819 btrfs_put_ordered_extent(ordered);
820 break;
821 }
822 btrfs_start_ordered_extent(inode, ordered, 1);
823 end = ordered->file_offset;
824 if (test_bit(BTRFS_ORDERED_IOERR, &ordered->flags))
825 ret = -EIO;
826 btrfs_put_ordered_extent(ordered);
827 if (ret || end == 0 || end == start)
828 break;
829 end--;
830 }
831 return ret_wb ? ret_wb : ret;
832}
833
834/*
835 * find an ordered extent corresponding to file_offset. return NULL if
836 * nothing is found, otherwise take a reference on the extent and return it
837 */
838struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct inode *inode,
839 u64 file_offset)
840{
841 struct btrfs_ordered_inode_tree *tree;
842 struct rb_node *node;
843 struct btrfs_ordered_extent *entry = NULL;
844
845 tree = &BTRFS_I(inode)->ordered_tree;
846 spin_lock_irq(&tree->lock);
847 node = tree_search(tree, file_offset);
848 if (!node)
849 goto out;
850
851 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
852 if (!offset_in_entry(entry, file_offset))
853 entry = NULL;
854 if (entry)
855 atomic_inc(&entry->refs);
856out:
857 spin_unlock_irq(&tree->lock);
858 return entry;
859}
860
861/* Since the DIO code tries to lock a wide area we need to look for any ordered
862 * extents that exist in the range, rather than just the start of the range.
863 */
864struct btrfs_ordered_extent *btrfs_lookup_ordered_range(struct inode *inode,
865 u64 file_offset,
866 u64 len)
867{
868 struct btrfs_ordered_inode_tree *tree;
869 struct rb_node *node;
870 struct btrfs_ordered_extent *entry = NULL;
871
872 tree = &BTRFS_I(inode)->ordered_tree;
873 spin_lock_irq(&tree->lock);
874 node = tree_search(tree, file_offset);
875 if (!node) {
876 node = tree_search(tree, file_offset + len);
877 if (!node)
878 goto out;
879 }
880
881 while (1) {
882 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
883 if (range_overlaps(entry, file_offset, len))
884 break;
885
886 if (entry->file_offset >= file_offset + len) {
887 entry = NULL;
888 break;
889 }
890 entry = NULL;
891 node = rb_next(node);
892 if (!node)
893 break;
894 }
895out:
896 if (entry)
897 atomic_inc(&entry->refs);
898 spin_unlock_irq(&tree->lock);
899 return entry;
900}
901
902bool btrfs_have_ordered_extents_in_range(struct inode *inode,
903 u64 file_offset,
904 u64 len)
905{
906 struct btrfs_ordered_extent *oe;
907
908 oe = btrfs_lookup_ordered_range(inode, file_offset, len);
909 if (oe) {
910 btrfs_put_ordered_extent(oe);
911 return true;
912 }
913 return false;
914}
915
916/*
917 * lookup and return any extent before 'file_offset'. NULL is returned
918 * if none is found
919 */
920struct btrfs_ordered_extent *
921btrfs_lookup_first_ordered_extent(struct inode *inode, u64 file_offset)
922{
923 struct btrfs_ordered_inode_tree *tree;
924 struct rb_node *node;
925 struct btrfs_ordered_extent *entry = NULL;
926
927 tree = &BTRFS_I(inode)->ordered_tree;
928 spin_lock_irq(&tree->lock);
929 node = tree_search(tree, file_offset);
930 if (!node)
931 goto out;
932
933 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
934 atomic_inc(&entry->refs);
935out:
936 spin_unlock_irq(&tree->lock);
937 return entry;
938}
939
940/*
941 * After an extent is done, call this to conditionally update the on disk
942 * i_size. i_size is updated to cover any fully written part of the file.
943 */
944int btrfs_ordered_update_i_size(struct inode *inode, u64 offset,
945 struct btrfs_ordered_extent *ordered)
946{
947 struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
948 u64 disk_i_size;
949 u64 new_i_size;
950 u64 i_size = i_size_read(inode);
951 struct rb_node *node;
952 struct rb_node *prev = NULL;
953 struct btrfs_ordered_extent *test;
954 int ret = 1;
955
956 spin_lock_irq(&tree->lock);
957 if (ordered) {
958 offset = entry_end(ordered);
959 if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags))
960 offset = min(offset,
961 ordered->file_offset +
962 ordered->truncated_len);
963 } else {
964 offset = ALIGN(offset, BTRFS_I(inode)->root->sectorsize);
965 }
966 disk_i_size = BTRFS_I(inode)->disk_i_size;
967
968 /* truncate file */
969 if (disk_i_size > i_size) {
970 BTRFS_I(inode)->disk_i_size = i_size;
971 ret = 0;
972 goto out;
973 }
974
975 /*
976 * if the disk i_size is already at the inode->i_size, or
977 * this ordered extent is inside the disk i_size, we're done
978 */
979 if (disk_i_size == i_size)
980 goto out;
981
982 /*
983 * We still need to update disk_i_size if outstanding_isize is greater
984 * than disk_i_size.
985 */
986 if (offset <= disk_i_size &&
987 (!ordered || ordered->outstanding_isize <= disk_i_size))
988 goto out;
989
990 /*
991 * walk backward from this ordered extent to disk_i_size.
992 * if we find an ordered extent then we can't update disk i_size
993 * yet
994 */
995 if (ordered) {
996 node = rb_prev(&ordered->rb_node);
997 } else {
998 prev = tree_search(tree, offset);
999 /*
1000 * we insert file extents without involving ordered struct,
1001 * so there should be no ordered struct cover this offset
1002 */
1003 if (prev) {
1004 test = rb_entry(prev, struct btrfs_ordered_extent,
1005 rb_node);
1006 BUG_ON(offset_in_entry(test, offset));
1007 }
1008 node = prev;
1009 }
1010 for (; node; node = rb_prev(node)) {
1011 test = rb_entry(node, struct btrfs_ordered_extent, rb_node);
1012
1013 /* We treat this entry as if it doesn't exist */
1014 if (test_bit(BTRFS_ORDERED_UPDATED_ISIZE, &test->flags))
1015 continue;
1016 if (test->file_offset + test->len <= disk_i_size)
1017 break;
1018 if (test->file_offset >= i_size)
1019 break;
1020 if (entry_end(test) > disk_i_size) {
1021 /*
1022 * we don't update disk_i_size now, so record this
1023 * undealt i_size. Or we will not know the real
1024 * i_size.
1025 */
1026 if (test->outstanding_isize < offset)
1027 test->outstanding_isize = offset;
1028 if (ordered &&
1029 ordered->outstanding_isize >
1030 test->outstanding_isize)
1031 test->outstanding_isize =
1032 ordered->outstanding_isize;
1033 goto out;
1034 }
1035 }
1036 new_i_size = min_t(u64, offset, i_size);
1037
1038 /*
1039 * Some ordered extents may completed before the current one, and
1040 * we hold the real i_size in ->outstanding_isize.
1041 */
1042 if (ordered && ordered->outstanding_isize > new_i_size)
1043 new_i_size = min_t(u64, ordered->outstanding_isize, i_size);
1044 BTRFS_I(inode)->disk_i_size = new_i_size;
1045 ret = 0;
1046out:
1047 /*
1048 * We need to do this because we can't remove ordered extents until
1049 * after the i_disk_size has been updated and then the inode has been
1050 * updated to reflect the change, so we need to tell anybody who finds
1051 * this ordered extent that we've already done all the real work, we
1052 * just haven't completed all the other work.
1053 */
1054 if (ordered)
1055 set_bit(BTRFS_ORDERED_UPDATED_ISIZE, &ordered->flags);
1056 spin_unlock_irq(&tree->lock);
1057 return ret;
1058}
1059
1060/*
1061 * search the ordered extents for one corresponding to 'offset' and
1062 * try to find a checksum. This is used because we allow pages to
1063 * be reclaimed before their checksum is actually put into the btree
1064 */
1065int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
1066 u32 *sum, int len)
1067{
1068 struct btrfs_ordered_sum *ordered_sum;
1069 struct btrfs_ordered_extent *ordered;
1070 struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
1071 unsigned long num_sectors;
1072 unsigned long i;
1073 u32 sectorsize = BTRFS_I(inode)->root->sectorsize;
1074 int index = 0;
1075
1076 ordered = btrfs_lookup_ordered_extent(inode, offset);
1077 if (!ordered)
1078 return 0;
1079
1080 spin_lock_irq(&tree->lock);
1081 list_for_each_entry_reverse(ordered_sum, &ordered->list, list) {
1082 if (disk_bytenr >= ordered_sum->bytenr &&
1083 disk_bytenr < ordered_sum->bytenr + ordered_sum->len) {
1084 i = (disk_bytenr - ordered_sum->bytenr) >>
1085 inode->i_sb->s_blocksize_bits;
1086 num_sectors = ordered_sum->len >>
1087 inode->i_sb->s_blocksize_bits;
1088 num_sectors = min_t(int, len - index, num_sectors - i);
1089 memcpy(sum + index, ordered_sum->sums + i,
1090 num_sectors);
1091
1092 index += (int)num_sectors;
1093 if (index == len)
1094 goto out;
1095 disk_bytenr += num_sectors * sectorsize;
1096 }
1097 }
1098out:
1099 spin_unlock_irq(&tree->lock);
1100 btrfs_put_ordered_extent(ordered);
1101 return index;
1102}
1103
1104int __init ordered_data_init(void)
1105{
1106 btrfs_ordered_extent_cache = kmem_cache_create("btrfs_ordered_extent",
1107 sizeof(struct btrfs_ordered_extent), 0,
1108 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
1109 NULL);
1110 if (!btrfs_ordered_extent_cache)
1111 return -ENOMEM;
1112
1113 return 0;
1114}
1115
1116void ordered_data_exit(void)
1117{
1118 kmem_cache_destroy(btrfs_ordered_extent_cache);
1119}