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, rb_link: 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(entry: 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(entry: 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(entry: 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(root: &inode->ordered_tree, file_offset, prev_ret: &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
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, start: file_offset, len: num_bytes);
160 if (ret < 0)
161 return ERR_PTR(error: 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, start: file_offset, len: num_bytes);
168 if (ret < 0)
169 return ERR_PTR(error: ret);
170 }
171 entry = kmem_cache_zalloc(k: btrfs_ordered_extent_cache, GFP_NOFS);
172 if (!entry)
173 return ERR_PTR(error: -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 = ret;
186 entry->flags = flags;
187 refcount_set(r: &entry->refs, n: 1);
188 init_waitqueue_head(&entry->wait);
189 INIT_LIST_HEAD(list: &entry->list);
190 INIT_LIST_HEAD(list: &entry->log_list);
191 INIT_LIST_HEAD(list: &entry->root_extent_list);
192 INIT_LIST_HEAD(list: &entry->work_list);
193 INIT_LIST_HEAD(list: &entry->bioc_list);
194 init_completion(x: &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(lock: &inode->lock);
202 btrfs_mod_outstanding_extents(inode, mod: 1);
203 spin_unlock(lock: &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(inode: 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, ordered: entry);
216
217 percpu_counter_add_batch(fbc: &fs_info->ordered_bytes, amount: entry->num_bytes,
218 batch: fs_info->delalloc_batch);
219
220 /* One ref for the tree. */
221 refcount_inc(r: &entry->refs);
222
223 spin_lock_irq(lock: &inode->ordered_tree_lock);
224 node = tree_insert(root: &inode->ordered_tree, file_offset: entry->file_offset,
225 node: &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(lock: &inode->ordered_tree_lock);
231
232 spin_lock(lock: &root->ordered_extent_lock);
233 list_add_tail(new: &entry->root_extent_list,
234 head: &root->ordered_extents);
235 root->nr_ordered_extents++;
236 if (root->nr_ordered_extents == 1) {
237 spin_lock(lock: &fs_info->ordered_root_lock);
238 BUG_ON(!list_empty(&root->ordered_root));
239 list_add_tail(new: &root->ordered_root, head: &fs_info->ordered_roots);
240 spin_unlock(lock: &fs_info->ordered_root_lock);
241 }
242 spin_unlock(lock: &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(ptr: 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(inode: entry->inode);
291
292 spin_lock_irq(lock: &inode->ordered_tree_lock);
293 list_add_tail(new: &sum->list, head: &entry->list);
294 spin_unlock_irq(lock: &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(inode: 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_page_test_ordered(fs_info, page, start: file_offset, len))
326 return false;
327 btrfs_page_clear_ordered(fs_info, page, start: file_offset, len);
328 }
329
330 /* Now we're fine to update the accounting. */
331 if (WARN_ON_ONCE(len > ordered->bytes_left)) {
332 btrfs_crit(fs_info,
333"bad ordered extent accounting, root=%llu ino=%llu OE offset=%llu OE len=%llu to_dec=%llu left=%llu",
334 inode->root->root_key.objectid, btrfs_ino(inode),
335 ordered->file_offset, ordered->num_bytes,
336 len, ordered->bytes_left);
337 ordered->bytes_left = 0;
338 } else {
339 ordered->bytes_left -= len;
340 }
341
342 if (!uptodate)
343 set_bit(nr: BTRFS_ORDERED_IOERR, addr: &ordered->flags);
344
345 if (ordered->bytes_left)
346 return false;
347
348 /*
349 * All the IO of the ordered extent is finished, we need to queue
350 * the finish_func to be executed.
351 */
352 set_bit(nr: BTRFS_ORDERED_IO_DONE, addr: &ordered->flags);
353 cond_wake_up(wq: &ordered->wait);
354 refcount_inc(r: &ordered->refs);
355 trace_btrfs_ordered_extent_mark_finished(inode, ordered);
356 return true;
357}
358
359static void btrfs_queue_ordered_fn(struct btrfs_ordered_extent *ordered)
360{
361 struct btrfs_inode *inode = BTRFS_I(inode: ordered->inode);
362 struct btrfs_fs_info *fs_info = inode->root->fs_info;
363 struct btrfs_workqueue *wq = btrfs_is_free_space_inode(inode) ?
364 fs_info->endio_freespace_worker : fs_info->endio_write_workers;
365
366 btrfs_init_work(work: &ordered->work, func: finish_ordered_fn, NULL);
367 btrfs_queue_work(wq, work: &ordered->work);
368}
369
370bool btrfs_finish_ordered_extent(struct btrfs_ordered_extent *ordered,
371 struct page *page, u64 file_offset, u64 len,
372 bool uptodate)
373{
374 struct btrfs_inode *inode = BTRFS_I(inode: ordered->inode);
375 unsigned long flags;
376 bool ret;
377
378 trace_btrfs_finish_ordered_extent(inode, start: file_offset, len, uptodate);
379
380 spin_lock_irqsave(&inode->ordered_tree_lock, flags);
381 ret = can_finish_ordered_extent(ordered, page, file_offset, len, uptodate);
382 spin_unlock_irqrestore(lock: &inode->ordered_tree_lock, flags);
383
384 if (ret)
385 btrfs_queue_ordered_fn(ordered);
386 return ret;
387}
388
389/*
390 * Mark all ordered extents io inside the specified range finished.
391 *
392 * @page: The involved page for the operation.
393 * For uncompressed buffered IO, the page status also needs to be
394 * updated to indicate whether the pending ordered io is finished.
395 * Can be NULL for direct IO and compressed write.
396 * For these cases, callers are ensured they won't execute the
397 * endio function twice.
398 *
399 * This function is called for endio, thus the range must have ordered
400 * extent(s) covering it.
401 */
402void btrfs_mark_ordered_io_finished(struct btrfs_inode *inode,
403 struct page *page, u64 file_offset,
404 u64 num_bytes, bool uptodate)
405{
406 struct rb_node *node;
407 struct btrfs_ordered_extent *entry = NULL;
408 unsigned long flags;
409 u64 cur = file_offset;
410
411 trace_btrfs_writepage_end_io_hook(inode, start: file_offset,
412 end: file_offset + num_bytes - 1,
413 uptodate);
414
415 spin_lock_irqsave(&inode->ordered_tree_lock, flags);
416 while (cur < file_offset + num_bytes) {
417 u64 entry_end;
418 u64 end;
419 u32 len;
420
421 node = ordered_tree_search(inode, file_offset: cur);
422 /* No ordered extents at all */
423 if (!node)
424 break;
425
426 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
427 entry_end = entry->file_offset + entry->num_bytes;
428 /*
429 * |<-- OE --->| |
430 * cur
431 * Go to next OE.
432 */
433 if (cur >= entry_end) {
434 node = rb_next(node);
435 /* No more ordered extents, exit */
436 if (!node)
437 break;
438 entry = rb_entry(node, struct btrfs_ordered_extent,
439 rb_node);
440
441 /* Go to next ordered extent and continue */
442 cur = entry->file_offset;
443 continue;
444 }
445 /*
446 * | |<--- OE --->|
447 * cur
448 * Go to the start of OE.
449 */
450 if (cur < entry->file_offset) {
451 cur = entry->file_offset;
452 continue;
453 }
454
455 /*
456 * Now we are definitely inside one ordered extent.
457 *
458 * |<--- OE --->|
459 * |
460 * cur
461 */
462 end = min(entry->file_offset + entry->num_bytes,
463 file_offset + num_bytes) - 1;
464 ASSERT(end + 1 - cur < U32_MAX);
465 len = end + 1 - cur;
466
467 if (can_finish_ordered_extent(ordered: entry, page, file_offset: cur, len, uptodate)) {
468 spin_unlock_irqrestore(lock: &inode->ordered_tree_lock, flags);
469 btrfs_queue_ordered_fn(ordered: entry);
470 spin_lock_irqsave(&inode->ordered_tree_lock, flags);
471 }
472 cur += len;
473 }
474 spin_unlock_irqrestore(lock: &inode->ordered_tree_lock, flags);
475}
476
477/*
478 * Finish IO for one ordered extent across a given range. The range can only
479 * contain one ordered extent.
480 *
481 * @cached: The cached ordered extent. If not NULL, we can skip the tree
482 * search and use the ordered extent directly.
483 * Will be also used to store the finished ordered extent.
484 * @file_offset: File offset for the finished IO
485 * @io_size: Length of the finish IO range
486 *
487 * Return true if the ordered extent is finished in the range, and update
488 * @cached.
489 * Return false otherwise.
490 *
491 * NOTE: The range can NOT cross multiple ordered extents.
492 * Thus caller should ensure the range doesn't cross ordered extents.
493 */
494bool btrfs_dec_test_ordered_pending(struct btrfs_inode *inode,
495 struct btrfs_ordered_extent **cached,
496 u64 file_offset, u64 io_size)
497{
498 struct rb_node *node;
499 struct btrfs_ordered_extent *entry = NULL;
500 unsigned long flags;
501 bool finished = false;
502
503 spin_lock_irqsave(&inode->ordered_tree_lock, flags);
504 if (cached && *cached) {
505 entry = *cached;
506 goto have_entry;
507 }
508
509 node = ordered_tree_search(inode, file_offset);
510 if (!node)
511 goto out;
512
513 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
514have_entry:
515 if (!in_range(file_offset, entry->file_offset, entry->num_bytes))
516 goto out;
517
518 if (io_size > entry->bytes_left)
519 btrfs_crit(inode->root->fs_info,
520 "bad ordered accounting left %llu size %llu",
521 entry->bytes_left, io_size);
522
523 entry->bytes_left -= io_size;
524
525 if (entry->bytes_left == 0) {
526 /*
527 * Ensure only one caller can set the flag and finished_ret
528 * accordingly
529 */
530 finished = !test_and_set_bit(nr: BTRFS_ORDERED_IO_DONE, addr: &entry->flags);
531 /* test_and_set_bit implies a barrier */
532 cond_wake_up_nomb(wq: &entry->wait);
533 }
534out:
535 if (finished && cached && entry) {
536 *cached = entry;
537 refcount_inc(r: &entry->refs);
538 trace_btrfs_ordered_extent_dec_test_pending(inode, ordered: entry);
539 }
540 spin_unlock_irqrestore(lock: &inode->ordered_tree_lock, flags);
541 return finished;
542}
543
544/*
545 * used to drop a reference on an ordered extent. This will free
546 * the extent if the last reference is dropped
547 */
548void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
549{
550 struct list_head *cur;
551 struct btrfs_ordered_sum *sum;
552
553 trace_btrfs_ordered_extent_put(inode: BTRFS_I(inode: entry->inode), ordered: entry);
554
555 if (refcount_dec_and_test(r: &entry->refs)) {
556 ASSERT(list_empty(&entry->root_extent_list));
557 ASSERT(list_empty(&entry->log_list));
558 ASSERT(RB_EMPTY_NODE(&entry->rb_node));
559 if (entry->inode)
560 btrfs_add_delayed_iput(inode: BTRFS_I(inode: entry->inode));
561 while (!list_empty(head: &entry->list)) {
562 cur = entry->list.next;
563 sum = list_entry(cur, struct btrfs_ordered_sum, list);
564 list_del(entry: &sum->list);
565 kvfree(addr: sum);
566 }
567 kmem_cache_free(s: btrfs_ordered_extent_cache, objp: entry);
568 }
569}
570
571/*
572 * remove an ordered extent from the tree. No references are dropped
573 * and waiters are woken up.
574 */
575void btrfs_remove_ordered_extent(struct btrfs_inode *btrfs_inode,
576 struct btrfs_ordered_extent *entry)
577{
578 struct btrfs_root *root = btrfs_inode->root;
579 struct btrfs_fs_info *fs_info = root->fs_info;
580 struct rb_node *node;
581 bool pending;
582 bool freespace_inode;
583
584 /*
585 * If this is a free space inode the thread has not acquired the ordered
586 * extents lockdep map.
587 */
588 freespace_inode = btrfs_is_free_space_inode(inode: btrfs_inode);
589
590 btrfs_lockdep_acquire(fs_info, btrfs_trans_pending_ordered);
591 /* This is paired with btrfs_alloc_ordered_extent. */
592 spin_lock(lock: &btrfs_inode->lock);
593 btrfs_mod_outstanding_extents(inode: btrfs_inode, mod: -1);
594 spin_unlock(lock: &btrfs_inode->lock);
595 if (root != fs_info->tree_root) {
596 u64 release;
597
598 if (test_bit(BTRFS_ORDERED_ENCODED, &entry->flags))
599 release = entry->disk_num_bytes;
600 else
601 release = entry->num_bytes;
602 btrfs_delalloc_release_metadata(inode: btrfs_inode, num_bytes: release, qgroup_free: false);
603 }
604
605 percpu_counter_add_batch(fbc: &fs_info->ordered_bytes, amount: -entry->num_bytes,
606 batch: fs_info->delalloc_batch);
607
608 spin_lock_irq(lock: &btrfs_inode->ordered_tree_lock);
609 node = &entry->rb_node;
610 rb_erase(node, &btrfs_inode->ordered_tree);
611 RB_CLEAR_NODE(node);
612 if (btrfs_inode->ordered_tree_last == node)
613 btrfs_inode->ordered_tree_last = NULL;
614 set_bit(nr: BTRFS_ORDERED_COMPLETE, addr: &entry->flags);
615 pending = test_and_clear_bit(nr: BTRFS_ORDERED_PENDING, addr: &entry->flags);
616 spin_unlock_irq(lock: &btrfs_inode->ordered_tree_lock);
617
618 /*
619 * The current running transaction is waiting on us, we need to let it
620 * know that we're complete and wake it up.
621 */
622 if (pending) {
623 struct btrfs_transaction *trans;
624
625 /*
626 * The checks for trans are just a formality, it should be set,
627 * but if it isn't we don't want to deref/assert under the spin
628 * lock, so be nice and check if trans is set, but ASSERT() so
629 * if it isn't set a developer will notice.
630 */
631 spin_lock(lock: &fs_info->trans_lock);
632 trans = fs_info->running_transaction;
633 if (trans)
634 refcount_inc(r: &trans->use_count);
635 spin_unlock(lock: &fs_info->trans_lock);
636
637 ASSERT(trans || BTRFS_FS_ERROR(fs_info));
638 if (trans) {
639 if (atomic_dec_and_test(v: &trans->pending_ordered))
640 wake_up(&trans->pending_wait);
641 btrfs_put_transaction(transaction: trans);
642 }
643 }
644
645 btrfs_lockdep_release(fs_info, btrfs_trans_pending_ordered);
646
647 spin_lock(lock: &root->ordered_extent_lock);
648 list_del_init(entry: &entry->root_extent_list);
649 root->nr_ordered_extents--;
650
651 trace_btrfs_ordered_extent_remove(inode: btrfs_inode, ordered: entry);
652
653 if (!root->nr_ordered_extents) {
654 spin_lock(lock: &fs_info->ordered_root_lock);
655 BUG_ON(list_empty(&root->ordered_root));
656 list_del_init(entry: &root->ordered_root);
657 spin_unlock(lock: &fs_info->ordered_root_lock);
658 }
659 spin_unlock(lock: &root->ordered_extent_lock);
660 wake_up(&entry->wait);
661 if (!freespace_inode)
662 btrfs_lockdep_release(fs_info, btrfs_ordered_extent);
663}
664
665static void btrfs_run_ordered_extent_work(struct btrfs_work *work)
666{
667 struct btrfs_ordered_extent *ordered;
668
669 ordered = container_of(work, struct btrfs_ordered_extent, flush_work);
670 btrfs_start_ordered_extent(entry: ordered);
671 complete(&ordered->completion);
672}
673
674/*
675 * wait for all the ordered extents in a root. This is done when balancing
676 * space between drives.
677 */
678u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,
679 const u64 range_start, const u64 range_len)
680{
681 struct btrfs_fs_info *fs_info = root->fs_info;
682 LIST_HEAD(splice);
683 LIST_HEAD(skipped);
684 LIST_HEAD(works);
685 struct btrfs_ordered_extent *ordered, *next;
686 u64 count = 0;
687 const u64 range_end = range_start + range_len;
688
689 mutex_lock(&root->ordered_extent_mutex);
690 spin_lock(lock: &root->ordered_extent_lock);
691 list_splice_init(list: &root->ordered_extents, head: &splice);
692 while (!list_empty(head: &splice) && nr) {
693 ordered = list_first_entry(&splice, struct btrfs_ordered_extent,
694 root_extent_list);
695
696 if (range_end <= ordered->disk_bytenr ||
697 ordered->disk_bytenr + ordered->disk_num_bytes <= range_start) {
698 list_move_tail(list: &ordered->root_extent_list, head: &skipped);
699 cond_resched_lock(&root->ordered_extent_lock);
700 continue;
701 }
702
703 list_move_tail(list: &ordered->root_extent_list,
704 head: &root->ordered_extents);
705 refcount_inc(r: &ordered->refs);
706 spin_unlock(lock: &root->ordered_extent_lock);
707
708 btrfs_init_work(work: &ordered->flush_work,
709 func: btrfs_run_ordered_extent_work, NULL);
710 list_add_tail(new: &ordered->work_list, head: &works);
711 btrfs_queue_work(wq: fs_info->flush_workers, work: &ordered->flush_work);
712
713 cond_resched();
714 spin_lock(lock: &root->ordered_extent_lock);
715 if (nr != U64_MAX)
716 nr--;
717 count++;
718 }
719 list_splice_tail(list: &skipped, head: &root->ordered_extents);
720 list_splice_tail(list: &splice, head: &root->ordered_extents);
721 spin_unlock(lock: &root->ordered_extent_lock);
722
723 list_for_each_entry_safe(ordered, next, &works, work_list) {
724 list_del_init(entry: &ordered->work_list);
725 wait_for_completion(&ordered->completion);
726 btrfs_put_ordered_extent(entry: ordered);
727 cond_resched();
728 }
729 mutex_unlock(lock: &root->ordered_extent_mutex);
730
731 return count;
732}
733
734void btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,
735 const u64 range_start, const u64 range_len)
736{
737 struct btrfs_root *root;
738 LIST_HEAD(splice);
739 u64 done;
740
741 mutex_lock(&fs_info->ordered_operations_mutex);
742 spin_lock(lock: &fs_info->ordered_root_lock);
743 list_splice_init(list: &fs_info->ordered_roots, head: &splice);
744 while (!list_empty(head: &splice) && nr) {
745 root = list_first_entry(&splice, struct btrfs_root,
746 ordered_root);
747 root = btrfs_grab_root(root);
748 BUG_ON(!root);
749 list_move_tail(list: &root->ordered_root,
750 head: &fs_info->ordered_roots);
751 spin_unlock(lock: &fs_info->ordered_root_lock);
752
753 done = btrfs_wait_ordered_extents(root, nr,
754 range_start, range_len);
755 btrfs_put_root(root);
756
757 spin_lock(lock: &fs_info->ordered_root_lock);
758 if (nr != U64_MAX) {
759 nr -= done;
760 }
761 }
762 list_splice_tail(list: &splice, head: &fs_info->ordered_roots);
763 spin_unlock(lock: &fs_info->ordered_root_lock);
764 mutex_unlock(lock: &fs_info->ordered_operations_mutex);
765}
766
767/*
768 * Start IO and wait for a given ordered extent to finish.
769 *
770 * Wait on page writeback for all the pages in the extent and the IO completion
771 * code to insert metadata into the btree corresponding to the extent.
772 */
773void btrfs_start_ordered_extent(struct btrfs_ordered_extent *entry)
774{
775 u64 start = entry->file_offset;
776 u64 end = start + entry->num_bytes - 1;
777 struct btrfs_inode *inode = BTRFS_I(inode: entry->inode);
778 bool freespace_inode;
779
780 trace_btrfs_ordered_extent_start(inode, ordered: entry);
781
782 /*
783 * If this is a free space inode do not take the ordered extents lockdep
784 * map.
785 */
786 freespace_inode = btrfs_is_free_space_inode(inode);
787
788 /*
789 * pages in the range can be dirty, clean or writeback. We
790 * start IO on any dirty ones so the wait doesn't stall waiting
791 * for the flusher thread to find them
792 */
793 if (!test_bit(BTRFS_ORDERED_DIRECT, &entry->flags))
794 filemap_fdatawrite_range(mapping: inode->vfs_inode.i_mapping, start, end);
795
796 if (!freespace_inode)
797 btrfs_might_wait_for_event(inode->root->fs_info, btrfs_ordered_extent);
798 wait_event(entry->wait, test_bit(BTRFS_ORDERED_COMPLETE, &entry->flags));
799}
800
801/*
802 * Used to wait on ordered extents across a large range of bytes.
803 */
804int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len)
805{
806 int ret = 0;
807 int ret_wb = 0;
808 u64 end;
809 u64 orig_end;
810 struct btrfs_ordered_extent *ordered;
811
812 if (start + len < start) {
813 orig_end = OFFSET_MAX;
814 } else {
815 orig_end = start + len - 1;
816 if (orig_end > OFFSET_MAX)
817 orig_end = OFFSET_MAX;
818 }
819
820 /* start IO across the range first to instantiate any delalloc
821 * extents
822 */
823 ret = btrfs_fdatawrite_range(inode, start, end: orig_end);
824 if (ret)
825 return ret;
826
827 /*
828 * If we have a writeback error don't return immediately. Wait first
829 * for any ordered extents that haven't completed yet. This is to make
830 * sure no one can dirty the same page ranges and call writepages()
831 * before the ordered extents complete - to avoid failures (-EEXIST)
832 * when adding the new ordered extents to the ordered tree.
833 */
834 ret_wb = filemap_fdatawait_range(inode->i_mapping, lstart: start, lend: orig_end);
835
836 end = orig_end;
837 while (1) {
838 ordered = btrfs_lookup_first_ordered_extent(inode: BTRFS_I(inode), file_offset: end);
839 if (!ordered)
840 break;
841 if (ordered->file_offset > orig_end) {
842 btrfs_put_ordered_extent(entry: ordered);
843 break;
844 }
845 if (ordered->file_offset + ordered->num_bytes <= start) {
846 btrfs_put_ordered_extent(entry: ordered);
847 break;
848 }
849 btrfs_start_ordered_extent(entry: ordered);
850 end = ordered->file_offset;
851 /*
852 * If the ordered extent had an error save the error but don't
853 * exit without waiting first for all other ordered extents in
854 * the range to complete.
855 */
856 if (test_bit(BTRFS_ORDERED_IOERR, &ordered->flags))
857 ret = -EIO;
858 btrfs_put_ordered_extent(entry: ordered);
859 if (end == 0 || end == start)
860 break;
861 end--;
862 }
863 return ret_wb ? ret_wb : ret;
864}
865
866/*
867 * find an ordered extent corresponding to file_offset. return NULL if
868 * nothing is found, otherwise take a reference on the extent and return it
869 */
870struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct btrfs_inode *inode,
871 u64 file_offset)
872{
873 struct rb_node *node;
874 struct btrfs_ordered_extent *entry = NULL;
875 unsigned long flags;
876
877 spin_lock_irqsave(&inode->ordered_tree_lock, flags);
878 node = ordered_tree_search(inode, file_offset);
879 if (!node)
880 goto out;
881
882 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
883 if (!in_range(file_offset, entry->file_offset, entry->num_bytes))
884 entry = NULL;
885 if (entry) {
886 refcount_inc(r: &entry->refs);
887 trace_btrfs_ordered_extent_lookup(inode, ordered: entry);
888 }
889out:
890 spin_unlock_irqrestore(lock: &inode->ordered_tree_lock, flags);
891 return entry;
892}
893
894/* Since the DIO code tries to lock a wide area we need to look for any ordered
895 * extents that exist in the range, rather than just the start of the range.
896 */
897struct btrfs_ordered_extent *btrfs_lookup_ordered_range(
898 struct btrfs_inode *inode, u64 file_offset, u64 len)
899{
900 struct rb_node *node;
901 struct btrfs_ordered_extent *entry = NULL;
902
903 spin_lock_irq(lock: &inode->ordered_tree_lock);
904 node = ordered_tree_search(inode, file_offset);
905 if (!node) {
906 node = ordered_tree_search(inode, file_offset: file_offset + len);
907 if (!node)
908 goto out;
909 }
910
911 while (1) {
912 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
913 if (range_overlaps(entry, file_offset, len))
914 break;
915
916 if (entry->file_offset >= file_offset + len) {
917 entry = NULL;
918 break;
919 }
920 entry = NULL;
921 node = rb_next(node);
922 if (!node)
923 break;
924 }
925out:
926 if (entry) {
927 refcount_inc(r: &entry->refs);
928 trace_btrfs_ordered_extent_lookup_range(inode, ordered: entry);
929 }
930 spin_unlock_irq(lock: &inode->ordered_tree_lock);
931 return entry;
932}
933
934/*
935 * Adds all ordered extents to the given list. The list ends up sorted by the
936 * file_offset of the ordered extents.
937 */
938void btrfs_get_ordered_extents_for_logging(struct btrfs_inode *inode,
939 struct list_head *list)
940{
941 struct rb_node *n;
942
943 ASSERT(inode_is_locked(&inode->vfs_inode));
944
945 spin_lock_irq(lock: &inode->ordered_tree_lock);
946 for (n = rb_first(&inode->ordered_tree); n; n = rb_next(n)) {
947 struct btrfs_ordered_extent *ordered;
948
949 ordered = rb_entry(n, struct btrfs_ordered_extent, rb_node);
950
951 if (test_bit(BTRFS_ORDERED_LOGGED, &ordered->flags))
952 continue;
953
954 ASSERT(list_empty(&ordered->log_list));
955 list_add_tail(new: &ordered->log_list, head: list);
956 refcount_inc(r: &ordered->refs);
957 trace_btrfs_ordered_extent_lookup_for_logging(inode, ordered);
958 }
959 spin_unlock_irq(lock: &inode->ordered_tree_lock);
960}
961
962/*
963 * lookup and return any extent before 'file_offset'. NULL is returned
964 * if none is found
965 */
966struct btrfs_ordered_extent *
967btrfs_lookup_first_ordered_extent(struct btrfs_inode *inode, u64 file_offset)
968{
969 struct rb_node *node;
970 struct btrfs_ordered_extent *entry = NULL;
971
972 spin_lock_irq(lock: &inode->ordered_tree_lock);
973 node = ordered_tree_search(inode, file_offset);
974 if (!node)
975 goto out;
976
977 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
978 refcount_inc(r: &entry->refs);
979 trace_btrfs_ordered_extent_lookup_first(inode, ordered: entry);
980out:
981 spin_unlock_irq(lock: &inode->ordered_tree_lock);
982 return entry;
983}
984
985/*
986 * Lookup the first ordered extent that overlaps the range
987 * [@file_offset, @file_offset + @len).
988 *
989 * The difference between this and btrfs_lookup_first_ordered_extent() is
990 * that this one won't return any ordered extent that does not overlap the range.
991 * And the difference against btrfs_lookup_ordered_extent() is, this function
992 * ensures the first ordered extent gets returned.
993 */
994struct btrfs_ordered_extent *btrfs_lookup_first_ordered_range(
995 struct btrfs_inode *inode, u64 file_offset, u64 len)
996{
997 struct rb_node *node;
998 struct rb_node *cur;
999 struct rb_node *prev;
1000 struct rb_node *next;
1001 struct btrfs_ordered_extent *entry = NULL;
1002
1003 spin_lock_irq(lock: &inode->ordered_tree_lock);
1004 node = inode->ordered_tree.rb_node;
1005 /*
1006 * Here we don't want to use tree_search() which will use tree->last
1007 * and screw up the search order.
1008 * And __tree_search() can't return the adjacent ordered extents
1009 * either, thus here we do our own search.
1010 */
1011 while (node) {
1012 entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
1013
1014 if (file_offset < entry->file_offset) {
1015 node = node->rb_left;
1016 } else if (file_offset >= entry_end(entry)) {
1017 node = node->rb_right;
1018 } else {
1019 /*
1020 * Direct hit, got an ordered extent that starts at
1021 * @file_offset
1022 */
1023 goto out;
1024 }
1025 }
1026 if (!entry) {
1027 /* Empty tree */
1028 goto out;
1029 }
1030
1031 cur = &entry->rb_node;
1032 /* We got an entry around @file_offset, check adjacent entries */
1033 if (entry->file_offset < file_offset) {
1034 prev = cur;
1035 next = rb_next(cur);
1036 } else {
1037 prev = rb_prev(cur);
1038 next = cur;
1039 }
1040 if (prev) {
1041 entry = rb_entry(prev, struct btrfs_ordered_extent, rb_node);
1042 if (range_overlaps(entry, file_offset, len))
1043 goto out;
1044 }
1045 if (next) {
1046 entry = rb_entry(next, struct btrfs_ordered_extent, rb_node);
1047 if (range_overlaps(entry, file_offset, len))
1048 goto out;
1049 }
1050 /* No ordered extent in the range */
1051 entry = NULL;
1052out:
1053 if (entry) {
1054 refcount_inc(r: &entry->refs);
1055 trace_btrfs_ordered_extent_lookup_first_range(inode, ordered: entry);
1056 }
1057
1058 spin_unlock_irq(lock: &inode->ordered_tree_lock);
1059 return entry;
1060}
1061
1062/*
1063 * Lock the passed range and ensures all pending ordered extents in it are run
1064 * to completion.
1065 *
1066 * @inode: Inode whose ordered tree is to be searched
1067 * @start: Beginning of range to flush
1068 * @end: Last byte of range to lock
1069 * @cached_state: If passed, will return the extent state responsible for the
1070 * locked range. It's the caller's responsibility to free the
1071 * cached state.
1072 *
1073 * Always return with the given range locked, ensuring after it's called no
1074 * order extent can be pending.
1075 */
1076void btrfs_lock_and_flush_ordered_range(struct btrfs_inode *inode, u64 start,
1077 u64 end,
1078 struct extent_state **cached_state)
1079{
1080 struct btrfs_ordered_extent *ordered;
1081 struct extent_state *cache = NULL;
1082 struct extent_state **cachedp = &cache;
1083
1084 if (cached_state)
1085 cachedp = cached_state;
1086
1087 while (1) {
1088 lock_extent(tree: &inode->io_tree, start, end, cached: cachedp);
1089 ordered = btrfs_lookup_ordered_range(inode, file_offset: start,
1090 len: end - start + 1);
1091 if (!ordered) {
1092 /*
1093 * If no external cached_state has been passed then
1094 * decrement the extra ref taken for cachedp since we
1095 * aren't exposing it outside of this function
1096 */
1097 if (!cached_state)
1098 refcount_dec(r: &cache->refs);
1099 break;
1100 }
1101 unlock_extent(tree: &inode->io_tree, start, end, cached: cachedp);
1102 btrfs_start_ordered_extent(entry: ordered);
1103 btrfs_put_ordered_extent(entry: ordered);
1104 }
1105}
1106
1107/*
1108 * Lock the passed range and ensure all pending ordered extents in it are run
1109 * to completion in nowait mode.
1110 *
1111 * Return true if btrfs_lock_ordered_range does not return any extents,
1112 * otherwise false.
1113 */
1114bool btrfs_try_lock_ordered_range(struct btrfs_inode *inode, u64 start, u64 end,
1115 struct extent_state **cached_state)
1116{
1117 struct btrfs_ordered_extent *ordered;
1118
1119 if (!try_lock_extent(tree: &inode->io_tree, start, end, cached: cached_state))
1120 return false;
1121
1122 ordered = btrfs_lookup_ordered_range(inode, file_offset: start, len: end - start + 1);
1123 if (!ordered)
1124 return true;
1125
1126 btrfs_put_ordered_extent(entry: ordered);
1127 unlock_extent(tree: &inode->io_tree, start, end, cached: cached_state);
1128
1129 return false;
1130}
1131
1132/* Split out a new ordered extent for this first @len bytes of @ordered. */
1133struct btrfs_ordered_extent *btrfs_split_ordered_extent(
1134 struct btrfs_ordered_extent *ordered, u64 len)
1135{
1136 struct btrfs_inode *inode = BTRFS_I(inode: ordered->inode);
1137 struct btrfs_root *root = inode->root;
1138 struct btrfs_fs_info *fs_info = root->fs_info;
1139 u64 file_offset = ordered->file_offset;
1140 u64 disk_bytenr = ordered->disk_bytenr;
1141 unsigned long flags = ordered->flags;
1142 struct btrfs_ordered_sum *sum, *tmpsum;
1143 struct btrfs_ordered_extent *new;
1144 struct rb_node *node;
1145 u64 offset = 0;
1146
1147 trace_btrfs_ordered_extent_split(inode, ordered);
1148
1149 ASSERT(!(flags & (1U << BTRFS_ORDERED_COMPRESSED)));
1150
1151 /*
1152 * The entire bio must be covered by the ordered extent, but we can't
1153 * reduce the original extent to a zero length either.
1154 */
1155 if (WARN_ON_ONCE(len >= ordered->num_bytes))
1156 return ERR_PTR(error: -EINVAL);
1157 /* We cannot split partially completed ordered extents. */
1158 if (ordered->bytes_left) {
1159 ASSERT(!(flags & ~BTRFS_ORDERED_TYPE_FLAGS));
1160 if (WARN_ON_ONCE(ordered->bytes_left != ordered->disk_num_bytes))
1161 return ERR_PTR(error: -EINVAL);
1162 }
1163 /* We cannot split a compressed ordered extent. */
1164 if (WARN_ON_ONCE(ordered->disk_num_bytes != ordered->num_bytes))
1165 return ERR_PTR(error: -EINVAL);
1166
1167 new = alloc_ordered_extent(inode, file_offset, num_bytes: len, ram_bytes: len, disk_bytenr,
1168 disk_num_bytes: len, offset: 0, flags, compress_type: ordered->compress_type);
1169 if (IS_ERR(ptr: new))
1170 return new;
1171
1172 /* One ref for the tree. */
1173 refcount_inc(r: &new->refs);
1174
1175 spin_lock_irq(lock: &root->ordered_extent_lock);
1176 spin_lock(lock: &inode->ordered_tree_lock);
1177 /* Remove from tree once */
1178 node = &ordered->rb_node;
1179 rb_erase(node, &inode->ordered_tree);
1180 RB_CLEAR_NODE(node);
1181 if (inode->ordered_tree_last == node)
1182 inode->ordered_tree_last = NULL;
1183
1184 ordered->file_offset += len;
1185 ordered->disk_bytenr += len;
1186 ordered->num_bytes -= len;
1187 ordered->disk_num_bytes -= len;
1188
1189 if (test_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags)) {
1190 ASSERT(ordered->bytes_left == 0);
1191 new->bytes_left = 0;
1192 } else {
1193 ordered->bytes_left -= len;
1194 }
1195
1196 if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags)) {
1197 if (ordered->truncated_len > len) {
1198 ordered->truncated_len -= len;
1199 } else {
1200 new->truncated_len = ordered->truncated_len;
1201 ordered->truncated_len = 0;
1202 }
1203 }
1204
1205 list_for_each_entry_safe(sum, tmpsum, &ordered->list, list) {
1206 if (offset == len)
1207 break;
1208 list_move_tail(list: &sum->list, head: &new->list);
1209 offset += sum->len;
1210 }
1211
1212 /* Re-insert the node */
1213 node = tree_insert(root: &inode->ordered_tree, file_offset: ordered->file_offset,
1214 node: &ordered->rb_node);
1215 if (node)
1216 btrfs_panic(fs_info, -EEXIST,
1217 "zoned: inconsistency in ordered tree at offset %llu",
1218 ordered->file_offset);
1219
1220 node = tree_insert(root: &inode->ordered_tree, file_offset: new->file_offset, node: &new->rb_node);
1221 if (node)
1222 btrfs_panic(fs_info, -EEXIST,
1223 "zoned: inconsistency in ordered tree at offset %llu",
1224 new->file_offset);
1225 spin_unlock(lock: &inode->ordered_tree_lock);
1226
1227 list_add_tail(new: &new->root_extent_list, head: &root->ordered_extents);
1228 root->nr_ordered_extents++;
1229 spin_unlock_irq(lock: &root->ordered_extent_lock);
1230 return new;
1231}
1232
1233int __init ordered_data_init(void)
1234{
1235 btrfs_ordered_extent_cache = kmem_cache_create(name: "btrfs_ordered_extent",
1236 size: sizeof(struct btrfs_ordered_extent), align: 0,
1237 SLAB_MEM_SPREAD,
1238 NULL);
1239 if (!btrfs_ordered_extent_cache)
1240 return -ENOMEM;
1241
1242 return 0;
1243}
1244
1245void __cold ordered_data_exit(void)
1246{
1247 kmem_cache_destroy(s: btrfs_ordered_extent_cache);
1248}
1249

source code of linux/fs/btrfs/ordered-data.c