Loading...
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
23static struct kmem_cache *btrfs_ordered_extent_cache;
24
25static u64 entry_end(struct btrfs_ordered_extent *entry)
26{
27 if (entry->file_offset + entry->num_bytes < entry->file_offset)
28 return (u64)-1;
29 return entry->file_offset + entry->num_bytes;
30}
31
32/* returns NULL if the insertion worked, or it returns the node it did find
33 * in the tree
34 */
35static struct rb_node *tree_insert(struct rb_root *root, u64 file_offset,
36 struct rb_node *node)
37{
38 struct rb_node **p = &root->rb_node;
39 struct rb_node *parent = NULL;
40 struct btrfs_ordered_extent *entry;
41
42 while (*p) {
43 parent = *p;
44 entry = rb_entry(parent, struct btrfs_ordered_extent, rb_node);
45
46 if (file_offset < entry->file_offset)
47 p = &(*p)->rb_left;
48 else if (file_offset >= entry_end(entry))
49 p = &(*p)->rb_right;
50 else
51 return parent;
52 }
53
54 rb_link_node(node, parent, p);
55 rb_insert_color(node, root);
56 return NULL;
57}
58
59/*
60 * look for a given offset in the tree, and if it can't be found return the
61 * first lesser offset
62 */
63static struct rb_node *__tree_search(struct rb_root *root, u64 file_offset,
64 struct rb_node **prev_ret)
65{
66 struct rb_node *n = root->rb_node;
67 struct rb_node *prev = NULL;
68 struct rb_node *test;
69 struct btrfs_ordered_extent *entry;
70 struct btrfs_ordered_extent *prev_entry = NULL;
71
72 while (n) {
73 entry = rb_entry(n, struct btrfs_ordered_extent, rb_node);
74 prev = n;
75 prev_entry = entry;
76
77 if (file_offset < entry->file_offset)
78 n = n->rb_left;
79 else if (file_offset >= entry_end(entry))
80 n = n->rb_right;
81 else
82 return n;
83 }
84 if (!prev_ret)
85 return NULL;
86
87 while (prev && file_offset >= entry_end(prev_entry)) {
88 test = rb_next(prev);
89 if (!test)
90 break;
91 prev_entry = rb_entry(test, struct btrfs_ordered_extent,
92 rb_node);
93 if (file_offset < entry_end(prev_entry))
94 break;
95
96 prev = test;
97 }
98 if (prev)
99 prev_entry = rb_entry(prev, struct btrfs_ordered_extent,
100 rb_node);
101 while (prev && file_offset < entry_end(prev_entry)) {
102 test = rb_prev(prev);
103 if (!test)
104 break;
105 prev_entry = rb_entry(test, struct btrfs_ordered_extent,
106 rb_node);
107 prev = test;
108 }
109 *prev_ret = prev;
110 return NULL;
111}
112
113static int range_overlaps(struct btrfs_ordered_extent *entry, u64 file_offset,
114 u64 len)
115{
116 if (file_offset + len <= entry->file_offset ||
117 entry->file_offset + entry->num_bytes <= file_offset)
118 return 0;
119 return 1;
120}
121
122/*
123 * look find the first ordered struct that has this offset, otherwise
124 * the first one less than this offset
125 */
126static inline struct rb_node *ordered_tree_search(struct btrfs_inode *inode,
127 u64 file_offset)
128{
129 struct rb_node *prev = NULL;
130 struct rb_node *ret;
131 struct btrfs_ordered_extent *entry;
132
133 if (inode->ordered_tree_last) {
134 entry = rb_entry(inode->ordered_tree_last, struct btrfs_ordered_extent,
135 rb_node);
136 if (in_range(file_offset, entry->file_offset, entry->num_bytes))
137 return inode->ordered_tree_last;
138 }
139 ret = __tree_search(&inode->ordered_tree, file_offset, &prev);
140 if (!ret)
141 ret = prev;
142 if (ret)
143 inode->ordered_tree_last = ret;
144 return ret;
145}
146
147static struct btrfs_ordered_extent *alloc_ordered_extent(
148 struct btrfs_inode *inode, u64 file_offset, u64 num_bytes,
149 u64 ram_bytes, u64 disk_bytenr, u64 disk_num_bytes,
150 u64 offset, unsigned long flags, int compress_type)
151{
152 struct btrfs_ordered_extent *entry;
153 int ret;
154 u64 qgroup_rsv = 0;
155
156 if (flags &
157 ((1 << BTRFS_ORDERED_NOCOW) | (1 << BTRFS_ORDERED_PREALLOC))) {
158 /* For nocow write, we can release the qgroup rsv right now */
159 ret = btrfs_qgroup_free_data(inode, NULL, file_offset, num_bytes, &qgroup_rsv);
160 if (ret < 0)
161 return ERR_PTR(ret);
162 } else {
163 /*
164 * The ordered extent has reserved qgroup space, release now
165 * and pass the reserved number for qgroup_record to free.
166 */
167 ret = btrfs_qgroup_release_data(inode, file_offset, num_bytes, &qgroup_rsv);
168 if (ret < 0)
169 return ERR_PTR(ret);
170 }
171 entry = kmem_cache_zalloc(btrfs_ordered_extent_cache, GFP_NOFS);
172 if (!entry)
173 return ERR_PTR(-ENOMEM);
174
175 entry->file_offset = file_offset;
176 entry->num_bytes = num_bytes;
177 entry->ram_bytes = ram_bytes;
178 entry->disk_bytenr = disk_bytenr;
179 entry->disk_num_bytes = disk_num_bytes;
180 entry->offset = offset;
181 entry->bytes_left = num_bytes;
182 entry->inode = igrab(&inode->vfs_inode);
183 entry->compress_type = compress_type;
184 entry->truncated_len = (u64)-1;
185 entry->qgroup_rsv = qgroup_rsv;
186 entry->flags = flags;
187 refcount_set(&entry->refs, 1);
188 init_waitqueue_head(&entry->wait);
189 INIT_LIST_HEAD(&entry->list);
190 INIT_LIST_HEAD(&entry->log_list);
191 INIT_LIST_HEAD(&entry->root_extent_list);
192 INIT_LIST_HEAD(&entry->work_list);
193 INIT_LIST_HEAD(&entry->bioc_list);
194 init_completion(&entry->completion);
195
196 /*
197 * We don't need the count_max_extents here, we can assume that all of
198 * that work has been done at higher layers, so this is truly the
199 * smallest the extent is going to get.
200 */
201 spin_lock(&inode->lock);
202 btrfs_mod_outstanding_extents(inode, 1);
203 spin_unlock(&inode->lock);
204
205 return entry;
206}
207
208static void insert_ordered_extent(struct btrfs_ordered_extent *entry)
209{
210 struct btrfs_inode *inode = BTRFS_I(entry->inode);
211 struct btrfs_root *root = inode->root;
212 struct btrfs_fs_info *fs_info = root->fs_info;
213 struct rb_node *node;
214
215 trace_btrfs_ordered_extent_add(inode, entry);
216
217 percpu_counter_add_batch(&fs_info->ordered_bytes, entry->num_bytes,
218 fs_info->delalloc_batch);
219
220 /* One ref for the tree. */
221 refcount_inc(&entry->refs);
222
223 spin_lock_irq(&inode->ordered_tree_lock);
224 node = tree_insert(&inode->ordered_tree, entry->file_offset,
225 &entry->rb_node);
226 if (node)
227 btrfs_panic(fs_info, -EEXIST,
228 "inconsistency in ordered tree at offset %llu",
229 entry->file_offset);
230 spin_unlock_irq(&inode->ordered_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(&fs_info->ordered_root_lock);
238 BUG_ON(!list_empty(&root->ordered_root));
239 list_add_tail(&root->ordered_root, &fs_info->ordered_roots);
240 spin_unlock(&fs_info->ordered_root_lock);
241 }
242 spin_unlock(&root->ordered_extent_lock);
243}
244
245/*
246 * Add an ordered extent to the per-inode tree.
247 *
248 * @inode: Inode that this extent is for.
249 * @file_offset: Logical offset in file where the extent starts.
250 * @num_bytes: Logical length of extent in file.
251 * @ram_bytes: Full length of unencoded data.
252 * @disk_bytenr: Offset of extent on disk.
253 * @disk_num_bytes: Size of extent on disk.
254 * @offset: Offset into unencoded data where file data starts.
255 * @flags: Flags specifying type of extent (1 << BTRFS_ORDERED_*).
256 * @compress_type: Compression algorithm used for data.
257 *
258 * Most of these parameters correspond to &struct btrfs_file_extent_item. The
259 * tree is given a single reference on the ordered extent that was inserted, and
260 * the returned pointer is given a second reference.
261 *
262 * Return: the new ordered extent or error pointer.
263 */
264struct btrfs_ordered_extent *btrfs_alloc_ordered_extent(
265 struct btrfs_inode *inode, u64 file_offset,
266 u64 num_bytes, u64 ram_bytes, u64 disk_bytenr,
267 u64 disk_num_bytes, u64 offset, unsigned long flags,
268 int compress_type)
269{
270 struct btrfs_ordered_extent *entry;
271
272 ASSERT((flags & ~BTRFS_ORDERED_TYPE_FLAGS) == 0);
273
274 entry = alloc_ordered_extent(inode, file_offset, num_bytes, ram_bytes,
275 disk_bytenr, disk_num_bytes, offset, flags,
276 compress_type);
277 if (!IS_ERR(entry))
278 insert_ordered_extent(entry);
279 return entry;
280}
281
282/*
283 * Add a struct btrfs_ordered_sum into the list of checksums to be inserted
284 * when an ordered extent is finished. If the list covers more than one
285 * ordered extent, it is split across multiples.
286 */
287void btrfs_add_ordered_sum(struct btrfs_ordered_extent *entry,
288 struct btrfs_ordered_sum *sum)
289{
290 struct btrfs_inode *inode = BTRFS_I(entry->inode);
291
292 spin_lock_irq(&inode->ordered_tree_lock);
293 list_add_tail(&sum->list, &entry->list);
294 spin_unlock_irq(&inode->ordered_tree_lock);
295}
296
297static void finish_ordered_fn(struct btrfs_work *work)
298{
299 struct btrfs_ordered_extent *ordered_extent;
300
301 ordered_extent = container_of(work, struct btrfs_ordered_extent, work);
302 btrfs_finish_ordered_io(ordered_extent);
303}
304
305static bool can_finish_ordered_extent(struct btrfs_ordered_extent *ordered,
306 struct page *page, u64 file_offset,
307 u64 len, bool uptodate)
308{
309 struct btrfs_inode *inode = BTRFS_I(ordered->inode);
310 struct btrfs_fs_info *fs_info = inode->root->fs_info;
311
312 lockdep_assert_held(&inode->ordered_tree_lock);
313
314 if (page) {
315 ASSERT(page->mapping);
316 ASSERT(page_offset(page) <= file_offset);
317 ASSERT(file_offset + len <= page_offset(page) + PAGE_SIZE);
318
319 /*
320 * Ordered (Private2) bit indicates whether we still have
321 * pending io unfinished for the ordered extent.
322 *
323 * If there's no such bit, we need to skip to next range.
324 */
325 if (!btrfs_folio_test_ordered(fs_info, page_folio(page),
326 file_offset, len))
327 return false;
328 btrfs_folio_clear_ordered(fs_info, page_folio(page), file_offset, len);
329 }
330
331 /* Now we're fine to update the accounting. */
332 if (WARN_ON_ONCE(len > ordered->bytes_left)) {
333 btrfs_crit(fs_info,
334"bad ordered extent accounting, root=%llu ino=%llu OE offset=%llu OE len=%llu to_dec=%llu left=%llu",
335 inode->root->root_key.objectid, btrfs_ino(inode),
336 ordered->file_offset, ordered->num_bytes,
337 len, ordered->bytes_left);
338 ordered->bytes_left = 0;
339 } else {
340 ordered->bytes_left -= len;
341 }
342
343 if (!uptodate)
344 set_bit(BTRFS_ORDERED_IOERR, &ordered->flags);
345
346 if (ordered->bytes_left)
347 return false;
348
349 /*
350 * All the IO of the ordered extent is finished, we need to queue
351 * the finish_func to be executed.
352 */
353 set_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags);
354 cond_wake_up(&ordered->wait);
355 refcount_inc(&ordered->refs);
356 trace_btrfs_ordered_extent_mark_finished(inode, ordered);
357 return true;
358}
359
360static void btrfs_queue_ordered_fn(struct btrfs_ordered_extent *ordered)
361{
362 struct btrfs_inode *inode = BTRFS_I(ordered->inode);
363 struct btrfs_fs_info *fs_info = inode->root->fs_info;
364 struct btrfs_workqueue *wq = btrfs_is_free_space_inode(inode) ?
365 fs_info->endio_freespace_worker : fs_info->endio_write_workers;
366
367 btrfs_init_work(&ordered->work, finish_ordered_fn, NULL);
368 btrfs_queue_work(wq, &ordered->work);
369}
370
371bool btrfs_finish_ordered_extent(struct btrfs_ordered_extent *ordered,
372 struct page *page, u64 file_offset, u64 len,
373 bool uptodate)
374{
375 struct btrfs_inode *inode = BTRFS_I(ordered->inode);
376 unsigned long flags;
377 bool ret;
378
379 trace_btrfs_finish_ordered_extent(inode, file_offset, len, uptodate);
380
381 spin_lock_irqsave(&inode->ordered_tree_lock, flags);
382 ret = can_finish_ordered_extent(ordered, page, file_offset, len, uptodate);
383 spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
384
385 if (ret)
386 btrfs_queue_ordered_fn(ordered);
387 return ret;
388}
389
390/*
391 * Mark all ordered extents io inside the specified range finished.
392 *
393 * @page: The involved page for the operation.
394 * For uncompressed buffered IO, the page status also needs to be
395 * updated to indicate whether the pending ordered io is finished.
396 * Can be NULL for direct IO and compressed write.
397 * For these cases, callers are ensured they won't execute the
398 * endio function twice.
399 *
400 * This function is called for endio, thus the range must have ordered
401 * extent(s) covering it.
402 */
403void btrfs_mark_ordered_io_finished(struct btrfs_inode *inode,
404 struct page *page, u64 file_offset,
405 u64 num_bytes, bool uptodate)
406{
407 struct rb_node *node;
408 struct btrfs_ordered_extent *entry = NULL;
409 unsigned long flags;
410 u64 cur = file_offset;
411
412 trace_btrfs_writepage_end_io_hook(inode, file_offset,
413 file_offset + num_bytes - 1,
414 uptodate);
415
416 spin_lock_irqsave(&inode->ordered_tree_lock, flags);
417 while (cur < file_offset + num_bytes) {
418 u64 entry_end;
419 u64 end;
420 u32 len;
421
422 node = ordered_tree_search(inode, cur);
423 /* No ordered extents at all */
424 if (!node)
425 break;
426
427 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
428 entry_end = entry->file_offset + entry->num_bytes;
429 /*
430 * |<-- OE --->| |
431 * cur
432 * Go to next OE.
433 */
434 if (cur >= entry_end) {
435 node = rb_next(node);
436 /* No more ordered extents, exit */
437 if (!node)
438 break;
439 entry = rb_entry(node, struct btrfs_ordered_extent,
440 rb_node);
441
442 /* Go to next ordered extent and continue */
443 cur = entry->file_offset;
444 continue;
445 }
446 /*
447 * | |<--- OE --->|
448 * cur
449 * Go to the start of OE.
450 */
451 if (cur < entry->file_offset) {
452 cur = entry->file_offset;
453 continue;
454 }
455
456 /*
457 * Now we are definitely inside one ordered extent.
458 *
459 * |<--- OE --->|
460 * |
461 * cur
462 */
463 end = min(entry->file_offset + entry->num_bytes,
464 file_offset + num_bytes) - 1;
465 ASSERT(end + 1 - cur < U32_MAX);
466 len = end + 1 - cur;
467
468 if (can_finish_ordered_extent(entry, page, cur, len, uptodate)) {
469 spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
470 btrfs_queue_ordered_fn(entry);
471 spin_lock_irqsave(&inode->ordered_tree_lock, flags);
472 }
473 cur += len;
474 }
475 spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
476}
477
478/*
479 * Finish IO for one ordered extent across a given range. The range can only
480 * contain one ordered extent.
481 *
482 * @cached: The cached ordered extent. If not NULL, we can skip the tree
483 * search and use the ordered extent directly.
484 * Will be also used to store the finished ordered extent.
485 * @file_offset: File offset for the finished IO
486 * @io_size: Length of the finish IO range
487 *
488 * Return true if the ordered extent is finished in the range, and update
489 * @cached.
490 * Return false otherwise.
491 *
492 * NOTE: The range can NOT cross multiple ordered extents.
493 * Thus caller should ensure the range doesn't cross ordered extents.
494 */
495bool btrfs_dec_test_ordered_pending(struct btrfs_inode *inode,
496 struct btrfs_ordered_extent **cached,
497 u64 file_offset, u64 io_size)
498{
499 struct rb_node *node;
500 struct btrfs_ordered_extent *entry = NULL;
501 unsigned long flags;
502 bool finished = false;
503
504 spin_lock_irqsave(&inode->ordered_tree_lock, flags);
505 if (cached && *cached) {
506 entry = *cached;
507 goto have_entry;
508 }
509
510 node = ordered_tree_search(inode, file_offset);
511 if (!node)
512 goto out;
513
514 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
515have_entry:
516 if (!in_range(file_offset, entry->file_offset, entry->num_bytes))
517 goto out;
518
519 if (io_size > entry->bytes_left)
520 btrfs_crit(inode->root->fs_info,
521 "bad ordered accounting left %llu size %llu",
522 entry->bytes_left, io_size);
523
524 entry->bytes_left -= io_size;
525
526 if (entry->bytes_left == 0) {
527 /*
528 * Ensure only one caller can set the flag and finished_ret
529 * accordingly
530 */
531 finished = !test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
532 /* test_and_set_bit implies a barrier */
533 cond_wake_up_nomb(&entry->wait);
534 }
535out:
536 if (finished && cached && entry) {
537 *cached = entry;
538 refcount_inc(&entry->refs);
539 trace_btrfs_ordered_extent_dec_test_pending(inode, entry);
540 }
541 spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
542 return finished;
543}
544
545/*
546 * used to drop a reference on an ordered extent. This will free
547 * the extent if the last reference is dropped
548 */
549void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
550{
551 struct list_head *cur;
552 struct btrfs_ordered_sum *sum;
553
554 trace_btrfs_ordered_extent_put(BTRFS_I(entry->inode), entry);
555
556 if (refcount_dec_and_test(&entry->refs)) {
557 ASSERT(list_empty(&entry->root_extent_list));
558 ASSERT(list_empty(&entry->log_list));
559 ASSERT(RB_EMPTY_NODE(&entry->rb_node));
560 if (entry->inode)
561 btrfs_add_delayed_iput(BTRFS_I(entry->inode));
562 while (!list_empty(&entry->list)) {
563 cur = entry->list.next;
564 sum = list_entry(cur, struct btrfs_ordered_sum, list);
565 list_del(&sum->list);
566 kvfree(sum);
567 }
568 kmem_cache_free(btrfs_ordered_extent_cache, entry);
569 }
570}
571
572/*
573 * remove an ordered extent from the tree. No references are dropped
574 * and waiters are woken up.
575 */
576void btrfs_remove_ordered_extent(struct btrfs_inode *btrfs_inode,
577 struct btrfs_ordered_extent *entry)
578{
579 struct btrfs_root *root = btrfs_inode->root;
580 struct btrfs_fs_info *fs_info = root->fs_info;
581 struct rb_node *node;
582 bool pending;
583 bool freespace_inode;
584
585 /*
586 * If this is a free space inode the thread has not acquired the ordered
587 * extents lockdep map.
588 */
589 freespace_inode = btrfs_is_free_space_inode(btrfs_inode);
590
591 btrfs_lockdep_acquire(fs_info, btrfs_trans_pending_ordered);
592 /* This is paired with btrfs_alloc_ordered_extent. */
593 spin_lock(&btrfs_inode->lock);
594 btrfs_mod_outstanding_extents(btrfs_inode, -1);
595 spin_unlock(&btrfs_inode->lock);
596 if (root != fs_info->tree_root) {
597 u64 release;
598
599 if (test_bit(BTRFS_ORDERED_ENCODED, &entry->flags))
600 release = entry->disk_num_bytes;
601 else
602 release = entry->num_bytes;
603 btrfs_delalloc_release_metadata(btrfs_inode, release,
604 test_bit(BTRFS_ORDERED_IOERR,
605 &entry->flags));
606 }
607
608 percpu_counter_add_batch(&fs_info->ordered_bytes, -entry->num_bytes,
609 fs_info->delalloc_batch);
610
611 spin_lock_irq(&btrfs_inode->ordered_tree_lock);
612 node = &entry->rb_node;
613 rb_erase(node, &btrfs_inode->ordered_tree);
614 RB_CLEAR_NODE(node);
615 if (btrfs_inode->ordered_tree_last == node)
616 btrfs_inode->ordered_tree_last = NULL;
617 set_bit(BTRFS_ORDERED_COMPLETE, &entry->flags);
618 pending = test_and_clear_bit(BTRFS_ORDERED_PENDING, &entry->flags);
619 spin_unlock_irq(&btrfs_inode->ordered_tree_lock);
620
621 /*
622 * The current running transaction is waiting on us, we need to let it
623 * know that we're complete and wake it up.
624 */
625 if (pending) {
626 struct btrfs_transaction *trans;
627
628 /*
629 * The checks for trans are just a formality, it should be set,
630 * but if it isn't we don't want to deref/assert under the spin
631 * lock, so be nice and check if trans is set, but ASSERT() so
632 * if it isn't set a developer will notice.
633 */
634 spin_lock(&fs_info->trans_lock);
635 trans = fs_info->running_transaction;
636 if (trans)
637 refcount_inc(&trans->use_count);
638 spin_unlock(&fs_info->trans_lock);
639
640 ASSERT(trans || BTRFS_FS_ERROR(fs_info));
641 if (trans) {
642 if (atomic_dec_and_test(&trans->pending_ordered))
643 wake_up(&trans->pending_wait);
644 btrfs_put_transaction(trans);
645 }
646 }
647
648 btrfs_lockdep_release(fs_info, btrfs_trans_pending_ordered);
649
650 spin_lock(&root->ordered_extent_lock);
651 list_del_init(&entry->root_extent_list);
652 root->nr_ordered_extents--;
653
654 trace_btrfs_ordered_extent_remove(btrfs_inode, entry);
655
656 if (!root->nr_ordered_extents) {
657 spin_lock(&fs_info->ordered_root_lock);
658 BUG_ON(list_empty(&root->ordered_root));
659 list_del_init(&root->ordered_root);
660 spin_unlock(&fs_info->ordered_root_lock);
661 }
662 spin_unlock(&root->ordered_extent_lock);
663 wake_up(&entry->wait);
664 if (!freespace_inode)
665 btrfs_lockdep_release(fs_info, btrfs_ordered_extent);
666}
667
668static void btrfs_run_ordered_extent_work(struct btrfs_work *work)
669{
670 struct btrfs_ordered_extent *ordered;
671
672 ordered = container_of(work, struct btrfs_ordered_extent, flush_work);
673 btrfs_start_ordered_extent(ordered);
674 complete(&ordered->completion);
675}
676
677/*
678 * wait for all the ordered extents in a root. This is done when balancing
679 * space between drives.
680 */
681u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,
682 const u64 range_start, const u64 range_len)
683{
684 struct btrfs_fs_info *fs_info = root->fs_info;
685 LIST_HEAD(splice);
686 LIST_HEAD(skipped);
687 LIST_HEAD(works);
688 struct btrfs_ordered_extent *ordered, *next;
689 u64 count = 0;
690 const u64 range_end = range_start + range_len;
691
692 mutex_lock(&root->ordered_extent_mutex);
693 spin_lock(&root->ordered_extent_lock);
694 list_splice_init(&root->ordered_extents, &splice);
695 while (!list_empty(&splice) && nr) {
696 ordered = list_first_entry(&splice, struct btrfs_ordered_extent,
697 root_extent_list);
698
699 if (range_end <= ordered->disk_bytenr ||
700 ordered->disk_bytenr + ordered->disk_num_bytes <= range_start) {
701 list_move_tail(&ordered->root_extent_list, &skipped);
702 cond_resched_lock(&root->ordered_extent_lock);
703 continue;
704 }
705
706 list_move_tail(&ordered->root_extent_list,
707 &root->ordered_extents);
708 refcount_inc(&ordered->refs);
709 spin_unlock(&root->ordered_extent_lock);
710
711 btrfs_init_work(&ordered->flush_work,
712 btrfs_run_ordered_extent_work, NULL);
713 list_add_tail(&ordered->work_list, &works);
714 btrfs_queue_work(fs_info->flush_workers, &ordered->flush_work);
715
716 cond_resched();
717 spin_lock(&root->ordered_extent_lock);
718 if (nr != U64_MAX)
719 nr--;
720 count++;
721 }
722 list_splice_tail(&skipped, &root->ordered_extents);
723 list_splice_tail(&splice, &root->ordered_extents);
724 spin_unlock(&root->ordered_extent_lock);
725
726 list_for_each_entry_safe(ordered, next, &works, work_list) {
727 list_del_init(&ordered->work_list);
728 wait_for_completion(&ordered->completion);
729 btrfs_put_ordered_extent(ordered);
730 cond_resched();
731 }
732 mutex_unlock(&root->ordered_extent_mutex);
733
734 return count;
735}
736
737void btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,
738 const u64 range_start, const u64 range_len)
739{
740 struct btrfs_root *root;
741 LIST_HEAD(splice);
742 u64 done;
743
744 mutex_lock(&fs_info->ordered_operations_mutex);
745 spin_lock(&fs_info->ordered_root_lock);
746 list_splice_init(&fs_info->ordered_roots, &splice);
747 while (!list_empty(&splice) && nr) {
748 root = list_first_entry(&splice, struct btrfs_root,
749 ordered_root);
750 root = btrfs_grab_root(root);
751 BUG_ON(!root);
752 list_move_tail(&root->ordered_root,
753 &fs_info->ordered_roots);
754 spin_unlock(&fs_info->ordered_root_lock);
755
756 done = btrfs_wait_ordered_extents(root, nr,
757 range_start, range_len);
758 btrfs_put_root(root);
759
760 spin_lock(&fs_info->ordered_root_lock);
761 if (nr != U64_MAX) {
762 nr -= done;
763 }
764 }
765 list_splice_tail(&splice, &fs_info->ordered_roots);
766 spin_unlock(&fs_info->ordered_root_lock);
767 mutex_unlock(&fs_info->ordered_operations_mutex);
768}
769
770/*
771 * Start IO and wait for a given ordered extent to finish.
772 *
773 * Wait on page writeback for all the pages in the extent and the IO completion
774 * code to insert metadata into the btree corresponding to the extent.
775 */
776void btrfs_start_ordered_extent(struct btrfs_ordered_extent *entry)
777{
778 u64 start = entry->file_offset;
779 u64 end = start + entry->num_bytes - 1;
780 struct btrfs_inode *inode = BTRFS_I(entry->inode);
781 bool freespace_inode;
782
783 trace_btrfs_ordered_extent_start(inode, entry);
784
785 /*
786 * If this is a free space inode do not take the ordered extents lockdep
787 * map.
788 */
789 freespace_inode = btrfs_is_free_space_inode(inode);
790
791 /*
792 * pages in the range can be dirty, clean or writeback. We
793 * start IO on any dirty ones so the wait doesn't stall waiting
794 * for the flusher thread to find them
795 */
796 if (!test_bit(BTRFS_ORDERED_DIRECT, &entry->flags))
797 filemap_fdatawrite_range(inode->vfs_inode.i_mapping, start, end);
798
799 if (!freespace_inode)
800 btrfs_might_wait_for_event(inode->root->fs_info, btrfs_ordered_extent);
801 wait_event(entry->wait, test_bit(BTRFS_ORDERED_COMPLETE, &entry->flags));
802}
803
804/*
805 * Used to wait on ordered extents across a large range of bytes.
806 */
807int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len)
808{
809 int ret = 0;
810 int ret_wb = 0;
811 u64 end;
812 u64 orig_end;
813 struct btrfs_ordered_extent *ordered;
814
815 if (start + len < start) {
816 orig_end = OFFSET_MAX;
817 } else {
818 orig_end = start + len - 1;
819 if (orig_end > OFFSET_MAX)
820 orig_end = OFFSET_MAX;
821 }
822
823 /* start IO across the range first to instantiate any delalloc
824 * extents
825 */
826 ret = btrfs_fdatawrite_range(inode, start, orig_end);
827 if (ret)
828 return ret;
829
830 /*
831 * If we have a writeback error don't return immediately. Wait first
832 * for any ordered extents that haven't completed yet. This is to make
833 * sure no one can dirty the same page ranges and call writepages()
834 * before the ordered extents complete - to avoid failures (-EEXIST)
835 * when adding the new ordered extents to the ordered tree.
836 */
837 ret_wb = filemap_fdatawait_range(inode->i_mapping, start, orig_end);
838
839 end = orig_end;
840 while (1) {
841 ordered = btrfs_lookup_first_ordered_extent(BTRFS_I(inode), end);
842 if (!ordered)
843 break;
844 if (ordered->file_offset > orig_end) {
845 btrfs_put_ordered_extent(ordered);
846 break;
847 }
848 if (ordered->file_offset + ordered->num_bytes <= start) {
849 btrfs_put_ordered_extent(ordered);
850 break;
851 }
852 btrfs_start_ordered_extent(ordered);
853 end = ordered->file_offset;
854 /*
855 * If the ordered extent had an error save the error but don't
856 * exit without waiting first for all other ordered extents in
857 * the range to complete.
858 */
859 if (test_bit(BTRFS_ORDERED_IOERR, &ordered->flags))
860 ret = -EIO;
861 btrfs_put_ordered_extent(ordered);
862 if (end == 0 || end == start)
863 break;
864 end--;
865 }
866 return ret_wb ? ret_wb : ret;
867}
868
869/*
870 * find an ordered extent corresponding to file_offset. return NULL if
871 * nothing is found, otherwise take a reference on the extent and return it
872 */
873struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct btrfs_inode *inode,
874 u64 file_offset)
875{
876 struct rb_node *node;
877 struct btrfs_ordered_extent *entry = NULL;
878 unsigned long flags;
879
880 spin_lock_irqsave(&inode->ordered_tree_lock, flags);
881 node = ordered_tree_search(inode, file_offset);
882 if (!node)
883 goto out;
884
885 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
886 if (!in_range(file_offset, entry->file_offset, entry->num_bytes))
887 entry = NULL;
888 if (entry) {
889 refcount_inc(&entry->refs);
890 trace_btrfs_ordered_extent_lookup(inode, entry);
891 }
892out:
893 spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);
894 return entry;
895}
896
897/* Since the DIO code tries to lock a wide area we need to look for any ordered
898 * extents that exist in the range, rather than just the start of the range.
899 */
900struct btrfs_ordered_extent *btrfs_lookup_ordered_range(
901 struct btrfs_inode *inode, u64 file_offset, u64 len)
902{
903 struct rb_node *node;
904 struct btrfs_ordered_extent *entry = NULL;
905
906 spin_lock_irq(&inode->ordered_tree_lock);
907 node = ordered_tree_search(inode, file_offset);
908 if (!node) {
909 node = ordered_tree_search(inode, file_offset + len);
910 if (!node)
911 goto out;
912 }
913
914 while (1) {
915 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
916 if (range_overlaps(entry, file_offset, len))
917 break;
918
919 if (entry->file_offset >= file_offset + len) {
920 entry = NULL;
921 break;
922 }
923 entry = NULL;
924 node = rb_next(node);
925 if (!node)
926 break;
927 }
928out:
929 if (entry) {
930 refcount_inc(&entry->refs);
931 trace_btrfs_ordered_extent_lookup_range(inode, entry);
932 }
933 spin_unlock_irq(&inode->ordered_tree_lock);
934 return entry;
935}
936
937/*
938 * Adds all ordered extents to the given list. The list ends up sorted by the
939 * file_offset of the ordered extents.
940 */
941void btrfs_get_ordered_extents_for_logging(struct btrfs_inode *inode,
942 struct list_head *list)
943{
944 struct rb_node *n;
945
946 ASSERT(inode_is_locked(&inode->vfs_inode));
947
948 spin_lock_irq(&inode->ordered_tree_lock);
949 for (n = rb_first(&inode->ordered_tree); n; n = rb_next(n)) {
950 struct btrfs_ordered_extent *ordered;
951
952 ordered = rb_entry(n, struct btrfs_ordered_extent, rb_node);
953
954 if (test_bit(BTRFS_ORDERED_LOGGED, &ordered->flags))
955 continue;
956
957 ASSERT(list_empty(&ordered->log_list));
958 list_add_tail(&ordered->log_list, list);
959 refcount_inc(&ordered->refs);
960 trace_btrfs_ordered_extent_lookup_for_logging(inode, ordered);
961 }
962 spin_unlock_irq(&inode->ordered_tree_lock);
963}
964
965/*
966 * lookup and return any extent before 'file_offset'. NULL is returned
967 * if none is found
968 */
969struct btrfs_ordered_extent *
970btrfs_lookup_first_ordered_extent(struct btrfs_inode *inode, u64 file_offset)
971{
972 struct rb_node *node;
973 struct btrfs_ordered_extent *entry = NULL;
974
975 spin_lock_irq(&inode->ordered_tree_lock);
976 node = ordered_tree_search(inode, file_offset);
977 if (!node)
978 goto out;
979
980 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
981 refcount_inc(&entry->refs);
982 trace_btrfs_ordered_extent_lookup_first(inode, entry);
983out:
984 spin_unlock_irq(&inode->ordered_tree_lock);
985 return entry;
986}
987
988/*
989 * Lookup the first ordered extent that overlaps the range
990 * [@file_offset, @file_offset + @len).
991 *
992 * The difference between this and btrfs_lookup_first_ordered_extent() is
993 * that this one won't return any ordered extent that does not overlap the range.
994 * And the difference against btrfs_lookup_ordered_extent() is, this function
995 * ensures the first ordered extent gets returned.
996 */
997struct btrfs_ordered_extent *btrfs_lookup_first_ordered_range(
998 struct btrfs_inode *inode, u64 file_offset, u64 len)
999{
1000 struct rb_node *node;
1001 struct rb_node *cur;
1002 struct rb_node *prev;
1003 struct rb_node *next;
1004 struct btrfs_ordered_extent *entry = NULL;
1005
1006 spin_lock_irq(&inode->ordered_tree_lock);
1007 node = inode->ordered_tree.rb_node;
1008 /*
1009 * Here we don't want to use tree_search() which will use tree->last
1010 * and screw up the search order.
1011 * And __tree_search() can't return the adjacent ordered extents
1012 * either, thus here we do our own search.
1013 */
1014 while (node) {
1015 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
1016
1017 if (file_offset < entry->file_offset) {
1018 node = node->rb_left;
1019 } else if (file_offset >= entry_end(entry)) {
1020 node = node->rb_right;
1021 } else {
1022 /*
1023 * Direct hit, got an ordered extent that starts at
1024 * @file_offset
1025 */
1026 goto out;
1027 }
1028 }
1029 if (!entry) {
1030 /* Empty tree */
1031 goto out;
1032 }
1033
1034 cur = &entry->rb_node;
1035 /* We got an entry around @file_offset, check adjacent entries */
1036 if (entry->file_offset < file_offset) {
1037 prev = cur;
1038 next = rb_next(cur);
1039 } else {
1040 prev = rb_prev(cur);
1041 next = cur;
1042 }
1043 if (prev) {
1044 entry = rb_entry(prev, struct btrfs_ordered_extent, rb_node);
1045 if (range_overlaps(entry, file_offset, len))
1046 goto out;
1047 }
1048 if (next) {
1049 entry = rb_entry(next, struct btrfs_ordered_extent, rb_node);
1050 if (range_overlaps(entry, file_offset, len))
1051 goto out;
1052 }
1053 /* No ordered extent in the range */
1054 entry = NULL;
1055out:
1056 if (entry) {
1057 refcount_inc(&entry->refs);
1058 trace_btrfs_ordered_extent_lookup_first_range(inode, entry);
1059 }
1060
1061 spin_unlock_irq(&inode->ordered_tree_lock);
1062 return entry;
1063}
1064
1065/*
1066 * Lock the passed range and ensures all pending ordered extents in it are run
1067 * to completion.
1068 *
1069 * @inode: Inode whose ordered tree is to be searched
1070 * @start: Beginning of range to flush
1071 * @end: Last byte of range to lock
1072 * @cached_state: If passed, will return the extent state responsible for the
1073 * locked range. It's the caller's responsibility to free the
1074 * cached state.
1075 *
1076 * Always return with the given range locked, ensuring after it's called no
1077 * order extent can be pending.
1078 */
1079void btrfs_lock_and_flush_ordered_range(struct btrfs_inode *inode, u64 start,
1080 u64 end,
1081 struct extent_state **cached_state)
1082{
1083 struct btrfs_ordered_extent *ordered;
1084 struct extent_state *cache = NULL;
1085 struct extent_state **cachedp = &cache;
1086
1087 if (cached_state)
1088 cachedp = cached_state;
1089
1090 while (1) {
1091 lock_extent(&inode->io_tree, start, end, cachedp);
1092 ordered = btrfs_lookup_ordered_range(inode, start,
1093 end - start + 1);
1094 if (!ordered) {
1095 /*
1096 * If no external cached_state has been passed then
1097 * decrement the extra ref taken for cachedp since we
1098 * aren't exposing it outside of this function
1099 */
1100 if (!cached_state)
1101 refcount_dec(&cache->refs);
1102 break;
1103 }
1104 unlock_extent(&inode->io_tree, start, end, cachedp);
1105 btrfs_start_ordered_extent(ordered);
1106 btrfs_put_ordered_extent(ordered);
1107 }
1108}
1109
1110/*
1111 * Lock the passed range and ensure all pending ordered extents in it are run
1112 * to completion in nowait mode.
1113 *
1114 * Return true if btrfs_lock_ordered_range does not return any extents,
1115 * otherwise false.
1116 */
1117bool btrfs_try_lock_ordered_range(struct btrfs_inode *inode, u64 start, u64 end,
1118 struct extent_state **cached_state)
1119{
1120 struct btrfs_ordered_extent *ordered;
1121
1122 if (!try_lock_extent(&inode->io_tree, start, end, cached_state))
1123 return false;
1124
1125 ordered = btrfs_lookup_ordered_range(inode, start, end - start + 1);
1126 if (!ordered)
1127 return true;
1128
1129 btrfs_put_ordered_extent(ordered);
1130 unlock_extent(&inode->io_tree, start, end, cached_state);
1131
1132 return false;
1133}
1134
1135/* Split out a new ordered extent for this first @len bytes of @ordered. */
1136struct btrfs_ordered_extent *btrfs_split_ordered_extent(
1137 struct btrfs_ordered_extent *ordered, u64 len)
1138{
1139 struct btrfs_inode *inode = BTRFS_I(ordered->inode);
1140 struct btrfs_root *root = inode->root;
1141 struct btrfs_fs_info *fs_info = root->fs_info;
1142 u64 file_offset = ordered->file_offset;
1143 u64 disk_bytenr = ordered->disk_bytenr;
1144 unsigned long flags = ordered->flags;
1145 struct btrfs_ordered_sum *sum, *tmpsum;
1146 struct btrfs_ordered_extent *new;
1147 struct rb_node *node;
1148 u64 offset = 0;
1149
1150 trace_btrfs_ordered_extent_split(inode, ordered);
1151
1152 ASSERT(!(flags & (1U << BTRFS_ORDERED_COMPRESSED)));
1153
1154 /*
1155 * The entire bio must be covered by the ordered extent, but we can't
1156 * reduce the original extent to a zero length either.
1157 */
1158 if (WARN_ON_ONCE(len >= ordered->num_bytes))
1159 return ERR_PTR(-EINVAL);
1160 /* We cannot split partially completed ordered extents. */
1161 if (ordered->bytes_left) {
1162 ASSERT(!(flags & ~BTRFS_ORDERED_TYPE_FLAGS));
1163 if (WARN_ON_ONCE(ordered->bytes_left != ordered->disk_num_bytes))
1164 return ERR_PTR(-EINVAL);
1165 }
1166 /* We cannot split a compressed ordered extent. */
1167 if (WARN_ON_ONCE(ordered->disk_num_bytes != ordered->num_bytes))
1168 return ERR_PTR(-EINVAL);
1169
1170 new = alloc_ordered_extent(inode, file_offset, len, len, disk_bytenr,
1171 len, 0, flags, ordered->compress_type);
1172 if (IS_ERR(new))
1173 return new;
1174
1175 /* One ref for the tree. */
1176 refcount_inc(&new->refs);
1177
1178 spin_lock_irq(&root->ordered_extent_lock);
1179 spin_lock(&inode->ordered_tree_lock);
1180 /* Remove from tree once */
1181 node = &ordered->rb_node;
1182 rb_erase(node, &inode->ordered_tree);
1183 RB_CLEAR_NODE(node);
1184 if (inode->ordered_tree_last == node)
1185 inode->ordered_tree_last = NULL;
1186
1187 ordered->file_offset += len;
1188 ordered->disk_bytenr += len;
1189 ordered->num_bytes -= len;
1190 ordered->disk_num_bytes -= len;
1191 ordered->ram_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(btrfs_ordered_extent, 0);
1240 if (!btrfs_ordered_extent_cache)
1241 return -ENOMEM;
1242
1243 return 0;
1244}
1245
1246void __cold ordered_data_exit(void)
1247{
1248 kmem_cache_destroy(btrfs_ordered_extent_cache);
1249}
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}